Performance information

• Semi-diurnal distribution of polycyclic aromatic hydrocarbons bound to PM2.5 and PM0.1 during pollution episode in the urban area of Hanoi　　　　　　　　　　　　　　　
  Thi Thao Nguyen; Bich Thuy Ly; T. Le Ha Vo; Dinh Binh Chu; T. Mai Huong Cao; Van Hoi Bui; Kazuhiko Sekiguchi; Dieu Anh Van
  Environmental Monitoring and Assessment, Volume：196, Number：8, Aug. 2024, [Reviewed]
  Every year, Hanoi suffers from several episodes (periods with daily concentration of PM2.5 higher than 50 µg m−3 during at least two consecutive days). These episodes are of health concern because of the high concentration of PM2.5 and/or PM0.1 and the presence of PM-bound toxic components, such as, PAHs. In this study, the concentrations of PAHs bound to PM2.5 and PM0.1 in night-time and day-time samples during episode and non-episode periods in December 2021 were determined. The concentrations of PAHs bound to PM2.5 were found to increase significantly from day-time samples of 3.24 ± 0.83 ng m−3 to night-time samples of 10.8 ± 4.45 ng m−3 in episode periods. However, PAHs bound to PM0.1 increased slightly from day-time samples of 0.58 ± 0.12 ng m−3 to night-time samples of 0.89 ± 0.30 ng m−3 in episode periods. Diagnostic ratios of PAHs indicate that biomass/coal combustion and vehicular emission are the primary sources of PAHs. The incremental lifetime cancer risk was estimated to vary from 8.7E-09 to 2.5E-08 for children and 6.7E-08 to 2.2E-07 for adults, respectively. Accordingly, loss of life expectancy was estimated at 0.11 min and 0.82 min for children and adults, respectively. These findings imply that the carcinogenic impact induced by PAHs via inhalation is negligible during the episode period.
  Scientific journal
  DOI：https://doi.org/10.1007/s10661-024-12923-5
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  DOI ID：10.1007/s10661-024-12923-5, ISSN：0167-6369, eISSN：1573-2959, PubMed ID：39088135, SCOPUS ID：85200259222
• Enhanced TiO2-Based Photocatalytic Volatile Organic Compound Decomposition Combined with Ultrasonic Atomization in the Co-Presence of Carbon Black and Heavy Metal Nanoparticles　　　　　　　　　　　　　　　
  Zen Maeno; Mika Nishitani; Takehiro Saito; Kazuhiko Sekiguchi; Naoki Kagi; Norikazu Namiki
  Molecules, Volume：29, Number：16, Aug. 2024, [Reviewed]
  Volatile organic compounds (VOCs) are representative indoor air pollutants that negatively affect the human body owing to their toxicity. One of the most promising methods for VOC removal is photocatalytic degradation using TiO2. In this study, the addition of carbon black (CB) and heavy metal nanoparticles (NPs) was investigated to improve the efficiency of a TiO2-based photocatalytic VOC decomposition system combined with ultrasonic atomization and ultraviolet irradiation, as described previously. The addition of CB and Ag NPs significantly improved the degradation efficiency. A comparison with other heavy metal nanoparticles and their respective roles are discussed.
  Scientific journal
  DOI：https://doi.org/10.3390/molecules29163819
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  DOI ID：10.3390/molecules29163819, eISSN：1420-3049, PubMed ID：39202898, SCOPUS ID：85202646086
• Effect of indoor and outdoor emission sources on the chemical compositions of PM2.5 and PM0.1 in residential and school buildings　　　　　　　　　　　　　　　
  Truong Thi Huyen; Kazuhiko Sekiguchi; Trung Dung Nghiem; Bich Thuy Ly
  Air Quality, Atmosphere and Health, Volume：17, Number：7, First page：1435, Last page：1450, Jul. 2024, [Reviewed]
  The chemical composition studies of indoor particulate matter (PM2.5 and PM0.1) are lacking in the developing world, yet the attention to indoor air pollution and occupant health risks is rising. This study therefore aims to investigate the chemical compositions of indoor and outdoor PM2.5 and PM0.1 in residential and school buildings in Vietnam during different seasons and the effects of emission sources on particle characteristics. The results show that the concentration of indoor PM2.5 in the residential house was higher than that outdoors, and the indoor-to-outdoor ratios (I/O) exceeded 1, indicating the contribution of indoor sources. The peak concentration of indoor particles was observed during the incense burning days, whereas a higher indoor organic carbon concentration may be due to cooking activities. A similar variation of indoor and outdoor PM2.5 indicates the penetration of outdoor particles. In the school building, seasonal variations in indoor PM0.1 and its chemical species were observed, suggesting outdoor sources had a significant effect. Several factors may affect I/O and the infiltration factor of PM0.1, such as indoor sources, air exchange rate, cracks in the door and window, and particle deposition rate. The reason for the I/O value slightly above 1 for PM0.1 in this study remained unclear. Further investigations are recommended to obtain knowledge regarding the penetration of particles, particularly PM0.1. The findings provide a better understanding of the chemical components of indoor particles and the effects of emission sources, which is crucial to developing management measures for indoor air quality and mitigating exposures.
  Scientific journal
  DOI：https://doi.org/10.1007/s11869-024-01518-1
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  DOI ID：10.1007/s11869-024-01518-1, ISSN：1873-9318, eISSN：1873-9326, SCOPUS ID：85184497375
• Size distribution of airborne particle-bound polycyclic aromatic hydrocarbons during rice straw open burning in Hanoi, Vietnam　　　　　　　　　　　　　　　
  Chau Thuy Pham; Trung Dung Nghiem; Huu Tuyen Le; Ha Duc Chu; Thu Tran Viet; Kazuhiko Sekiguchi; Ning Tang; Kazuichi Hayakawa; Akira Toriba
  Atmospheric Pollution Research, Volume：15, Number：6, Jun. 2024, [Reviewed]
  This study dealt with size distribution of airborne particle-bound polycyclic aromatic hydrocarbons (PAHs) during rice straw open burning (RSOB) and non-RSOB period in Hanoi. Two sampling campaigns for PAHs associated with airborne particles of six different sizes (PM0.1, PM0.1-0.5, PM0.5-1, PM1.0-2.5, PM2.5-10, PM> 10) were conducted at three sampling sites in Hanoi during 2018–2020. The average concentrations of total particle-bound PAHs were higher during RSOB period (11.7 ± 5.3 ng m−3) than during non-RSOB period (10.1 ± 5.4 ng m−3), and concentrations were significantly higher at the near-RSOB site (11.0 ± 4.9 ng m−3) than at the far-RSOB site (7.1 ± 3.4 ng m−3). Of the various PAHs, the average concentration of benz[a]anthracene (BaA) and benzo[a]pyrene (BaP) bound to PM0.1 and PM1-2.5 exhibited the greatest significant difference in between the near- and the far-RSOB site. The size distributions of total PAHs were unimodal with the maximum concentration in accumulation mode at all sampling locations. The four-ring PAHs shifted to slightly larger particles during the RSOB period (1.34–1.5 μm) compared to the non-RSOB period (0.87 μm) or with the distant site (1 μm). The concentrations of 5- and 6-ring PAHs remained stable in smaller particles, peaking at 0.8 μm. Diagnostic ratios implied biomass burning contributes to PAHs emissions in all sampling sites, while vehicular emission are the significant emission source in the far-RSOB site. This result provides a comprehensive understanding of the size distribution of particle-bound PAHs in the air during RSOB, and useful information for the intergrated air quality management in RSOB regions.
  Scientific journal
  DOI：https://doi.org/10.1016/j.apr.2024.102115
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  DOI ID：10.1016/j.apr.2024.102115, ISSN：1309-1042, SCOPUS ID：85188675322
• Influence of Secondary Inorganic Aerosol on the Concentrations of PM2.5 and PM0.1 during Air Pollution Episodes in Hanoi, Vietnam　　　　　　　　　　　　　　　
  Nguyen Quoc Dat; Bich Thuy Ly; Trung Dung Nghiem; Thu Thi Hien Nguyen; Kazuhiko Sekiguchi; Truong Thi Huyen; Thai Ha Vinh; Le Quang Tien
  Aerosol and Air Quality Research, Volume：24, Number：4, Apr. 2024, [Reviewed]
  The high concentration of PM2.5 in Hanoi has been an issue of great concern. There were several periods during the winter when PM2.5 concentrations were higher than the Vietnamese ambient air quality standards (NAAQS) and WHO guidelines for daily PM2.5. In this study, the periods when daily PM2.5 concentrations exceeded the NAAQS of 50 µg m–3 for a minimum of two consecutive days were determined as episode periods. The study focuses on the impact of secondary inorganic aerosol (SIA) on PM2.5 episodes in the dry winter period in Hanoi. To calculate SIA, water-soluble ions of daily PM2.5 and PM0.1 samples which were collected on the rooftop of a three-storeyed building at an urban site in Hanoi, Vietnam (HUST site) from October 14 to December 31, 2020, were analyzed. Levels and SIA of PM2.5 and PM0.1 at a transportation site (CEM site) in an episode period from December 20 to December 28, 2020 were also measured. The contribution of SIA on PM2.5 and PM0.1 during those episodes, the effects of meteorological conditions, and long-range transport were investigated. The results showed that SIA contributed on average 29.0% and 14.1%, respectively, to PM2.5 and PM0.1 concentrations during air pollution episodes at HUST. Those were higher than the average contribution percentages of total SIA to PM concentrations in non-episode periods for PM2.5 (25.6%) and PM0.1 (10.6%) at HUST. Among meteorological factors, wind speed largely affected PM2.5 concentration and SIA of PM2.5. Relative humidity, pressure, temperature, and radiation had a good correlation with SIA of PM0.1 and a moderate correlation with PM0.1. Concentration-weighted trajectory analysis demonstrated that PM2.5 and SIA levels were also influenced by long-range transportation from the upper areas. This study highlighted the importance and served as pioneered research on SIA contribution to PM2.5 episodes in the country.
  Scientific journal
  DOI：https://doi.org/10.4209/aaqr.220446
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  DOI ID：10.4209/aaqr.220446, ISSN：1680-8584, eISSN：2071-1409, SCOPUS ID：85190707821
• Characterisation of polycyclic aromatic hydrocarbons associated with indoor PM0.1 and PM2.5 in Hanoi and implications for health risks　　　　　　　　　　　　　　　
  Le Ha T. Vo; Minoru Yoneda; Trung Dung Nghiem; Kazuhiko Sekiguchi; Yuji Fujitani; Duc Nam Vu; Thu Hien T. Nguyen
  Environmental Pollution, Volume：343, Feb. 2024, [Reviewed]
  Polycyclic aromatic hydrocarbons (PAHs) associated with indoor PM pose a high risk to human health because of their toxicity. A total of 160 daily samples of indoor PM2.5 and PM0.1 were collected in Hanoi and analysed for 15 PAHs. In general, the concentrations of carcinogenic PAHs (car-PAHs) accounted for 21% ± 2%, 19.1% ± 2%, and 26% ± 3% of the concentrations of 15 PAHs in PM2.5, PM0.1-2.5, and PM0.1, respectively. Higher percentages of car-PAHs were found in smaller fractions (PM0.1), which can be easily deposited deep in the pulmonary regions of the human respiratory tract. The concentrations of 15 PAHs were higher in winter than in summer. The most abundant PAH species were naphthalene and phenanthrene, accounting for 11%–21% and 19%–23%, respectively. The PAH content in PM0.1 was almost twice as high as those in PM2.5 and PM0.1-2.5. Principal component analysis found that vehicle emissions and the combustion of biomass and coal were the main outdoor sources of PAHs, whereas indoor sources included cooking activities, the combustion of incense, scented candles, and domestic uses in houses. According to the results, 60%–90% of the PM0.1-bound BaP(eq) was deposited in the alveoli region, whereas 63%–75% of the PM2.5-bound BaP(eq) was deposited in head airways (HA), implying that most of the particles deposited in the HA region were PM0.1-2.5. The contributions of dibenz[a,h]anthracene and benzo[a]pyrene were dominant and contributed from 36% to 51% and 31%–50%, respectively, to the carcinogenic potential, whereas benzo[a]pyrene contributed from 30% to 49% to the mutagenic potential for both size fractions. The incremental lifetime cancer risk, simulated by Monte Carlo simulation, was within the limits set by the US EPA, indicating an acceptable risk for the occupants. These results provide an additional scientific basis for protecting human health from exposure to indoor PAHs.
  Scientific journal
  DOI：https://doi.org/10.1016/j.envpol.2023.123138
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  DOI ID：10.1016/j.envpol.2023.123138, ISSN：0269-7491, eISSN：1873-6424, PubMed ID：38097160, SCOPUS ID：85179885178
• Divisive Refinement of Metal Fiber at the PM0.1 Classification Stage for PM0.5-0.1 Sampling with Nanosampler　　　　　　　　　　　　　　　
  Yuta Kurotsuchi; Kazuhiko Sekiguchi; Yohei Hayakawa
  Aerosol and Air Quality Research, Volume：23, Number：5, May 2023, [Reviewed]
  Multi-component analysis of PM0.5-0.1 collected by Nanosampler II metal (Steel Use Stainless: SUS) wool fiber at the PM0.1 classification stage is challenging owing to difficulties in SUS wool fiber separation after collection. A 4-division (4D) cartridge was developed to enable quantitative analysis of multiple components by dividing the SUS wool fibers into four sections. The performance of the 4D cartridge was evaluated using sulfate ion concentrations of actual atmospheric particulate matter (PM). Observations using the 4D cartridge revealed that the relative standard deviation (RSD) of sulfate ions was lower for mesh with a large open area. In the case of the mesh with a large opening area, the partition did not block too much of the cross-sectional area of the SUS wool fiber, thus minimizing its effect on the airflow and possibly suppressing particle adhesion on the stainless-steel mesh. The PM0.1 classification efficiency test was conducted, and a linear analysis of the total filling mass of SUS wool fiber along with classifying efficiency of 100 nm PM was performed. In the 4D cartridge, it was estimated that 8.7 mg of SUS wool fiber was required to achieve a classification efficiency of 100 nm at 50% cutoff diameter because the apparent volume fraction of SUS wool fiber increases with the introduction of the partition. Using optimal mesh and amount of SUS wool fiber, the average RSD of sulfate ions was 5.6%, which was within the acceptable range (± 15%) for reanalysis of the Ministry of the Environment in Japan due to changes in analytical sensitivity of ionic components, confirming that PM was evenly collected from the four pieces of SUS wool fiber. This enabled multi-component analysis of all particle sizes including PM0.5-0.1 through the classified collection of PM using Nanosampler II.
  Scientific journal
  DOI：https://doi.org/10.4209/aaqr.220439
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  DOI ID：10.4209/aaqr.220439, ISSN：1680-8584, eISSN：2071-1409, SCOPUS ID：85159761113
• Assessment of traffic-related chemical components in ultrafine and fine particles in urban areas in Vietnam　　　　　　　　　　　　　　　
  Truong Thi Huyen; Kazuhiko Sekiguchi; Bich Thuy Ly; Trung Dung Nghiem
  Science of the Total Environment, Volume：858, Feb. 2023, [Reviewed]
  Ultrafine particles (UFPs or PM0.1; aerodynamic diameter ≤ 0.1 μm) were monitored at a roadside site (RS) in a populated area of Hanoi, Vietnam. Meanwhile, UFPs and fine particles (FPs or PM2.5, aerodynamic diameter ≤ 2.5 μm) were monitored at an ambient site (AS), located at an on-campus a university, approximately 200 m away from the RS. Sampling was conducted in different seasons–summer, winter, and the transitional periods of summer-to-winter and winter-to-summer (STP and WTP, respectively). Carbonaceous and ionic species in UFPs and FPs–rarely investigated in the study area–were analyzed to observe the seasonal variations, characteristics of UFPs near the roadway, and spatial differences between the sites. The UFPs concentration at the AS was in the order of winter > STP > WTP > summer, whereas that of the FPs was winter > WTP > STP > summer. This seasonal variation of particle concentration was possibly affected by the meteorological conditions, which contribute to the highest concentration in winter. The higher FPs concentration in WTP than in STP resulted from the substantial increase in ionic concentrations, particularly sulfate, nitrate, and ammonium. This result indicates the effect of secondary formation processes under drizzle-like weather, which is typical during WTP in northern Vietnam. Compared with UFPs at the AS, traffic-related emissions were more noticeable in UFPs at the RS, including a higher EC concentration and lower OC/EC ratio. The possibility of particle growth under favorable conditions, including the presence of gas-phase pollutants and the availability of surface areas owing to high UFPs concentration in Hanoi, may explain the low correlation of the chemical components between UFPs and FPs in the sites. This study serves as a reference for further investigation of the relationship between UFPs and FPs under highly polluted conditions in big cities in Vietnam in future studies.
  Scientific journal
  DOI：https://doi.org/10.1016/j.scitotenv.2022.159869
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  DOI ID：10.1016/j.scitotenv.2022.159869, ISSN：0048-9697, eISSN：1879-1026, PubMed ID：36328252, SCOPUS ID：85141341167
• Size-segregated chemical compositions of particulate matter including PM0.1 in northern Vietnam, a highly polluted area where notable seasonal episodes occur　　　　　　　　　　　　　　　
  Yuta Kurotsuchi; Kazuhiko Sekiguchi; Sota Konno; Truong Thi Huyen; Yuji Fujitani; Yutaka Matsumi; Kimiyo Kumagai; Nghiem Trung Dung; Ly Bich Thuy; Nguyen Thi Thu Thuy; Pham Chau Thuy
  Atmospheric Pollution Research, Aug. 2022, [Reviewed]
  Scientific journal
  DOI：https://doi.org/10.1016/j.apr.2022.101478
  DOI ID：10.1016/j.apr.2022.101478, ORCID：114158672
• Seasonal variation of size-fractionated particulate matter in residential houses in urban area in Vietnam: relationship of indoor and outdoor particulate matter and mass size distribution　　　　　　　　　　　　　　　
  Le Ha T. Vo; Minoru Yoneda; Trung Dung Nghiem; Kazuhiko Sekiguchi; Yuji Fujitani; Yoko Shimada
  E3S Web of Conferences, Volume：347, Apr. 2022
  The study aims to determine the concentration, size distribution and analyze the relationship of indoor and outdoor particles in urban area, in Vietnam. One thousand two hundred daily samples of PM0.1, PM0.1-0.5, PM0.5-1, PM1-2.5, PM2.5-10, PM>10 were taken simultaneously at four residential houses in summer and winter by nano sampler (Model 3182, Kinomax). The average concentrations of indoor PM0.1, PM0.5, PM1, PM2.5 and PM10 were in range of 5.3-8.9 µg/m3; 10.8-20.1µg/m3; 20.5-47.6 µg/m3; 33.7-105.9 µg/m3 and 44.7-135.0 µg/m3 among four houses, respectively. The concentrations of outdoor PM2.5, PM10 were considerately higher than those of indoor PM, whereas negligible differences on concentrations of PM0.1, PM0.5 and PM1 were observed. The significantly seasonal variation was observed for indoor PM1, PM2.5 and PM10, but not for PM0.1 and PM0.5. Majority of indoor fractions were origin from outdoor sources. Unimodal distributions of indoor particles determined the super-micron size (1 to 2.5 µm) with highest concentration and PM<0.5 and PM>10 with lowest concentration. Fine particles with interval sizes (PM0.5-1 and PM1-2.5) contributed to the predominance to coarse particles in both indoors and outdoors, suggesting serious threat on human health.
  International conference proceedings
  DOI：https://doi.org/10.1051/e3sconf/202234704020
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  DOI ID：10.1051/e3sconf/202234704020, ISSN：2555-0403, eISSN：2267-1242, SCOPUS ID：85146861540
• Mechanisms for removal of gaseous toluene in headspace using sonophysical and sonochemical effects at the gas–liquid interface　　　　　　　　　　　　　　　
  Akira Okada; Kazuhiko Sekiguchi; Kenshi Sankoda
  Journal of Hazardous Materials, Volume：423, Feb. 2022, [Reviewed]
  We developed a new method for removing gaseous substances by using high frequency (200 kHz) ultrasonic irradiation of water, and the effects of ultrasonic irradiation on gas-phase toluene were evaluated quantitatively for the first time. The removal ratio of gaseous toluene increased with increasing ultrasonic power, but the reaction was inhibited by the addition of radical scavengers, indicating that ultrasonic irradiation not only accelerated the dissolution of gaseous toluene but also induced toluene decomposition. The contribution made by OH radicals to the decomposition of gaseous toluene at the gas–liquid interface was confirmed by the difference in removal ratios between addition of KI and addition of tert-butyl alcohol. The toluene removal mechanism was investigated by studying the logarithmic plots for toluene concentration at specified times. The results of this study clearly showed the promotion of gaseous toluene dissolution and the reaction via OH radicals at the gas–liquid interface by sonophysical and sonochemical effects with both effects contributing to the removal of gaseous toluene. Furthermore, the total organic carbon concentration in the aqueous phase increased with increasing reaction time, indicating that the toluene degradation products were trapped and decomposed into low-molecular-weight organic compounds in the aqueous phase.
  Scientific journal
  DOI：https://doi.org/10.1016/j.jhazmat.2021.127221
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  DOI ID：10.1016/j.jhazmat.2021.127221, ISSN：0304-3894, eISSN：1873-3336, PubMed ID：34844351, SCOPUS ID：85117883782
• Levels and Compositions of Polycyclic Aromatic Hydrocarbons in Rainwater and Their Implication for Aquatic Environments in Urban Area in Saitama, Japan　　　　　　　　　　　　　　　
  Kenshi Sankoda; Saeka Ishikawa; Kazuhiko Sekiguchi
  POLYCYCLIC AROMATIC COMPOUNDS, Jul. 2021, [Reviewed]
  In this study, we investigated concentrations and profiles of polycyclic aromatic hydrocarbons (PAHs) in rainwater and surface water samples collected in Saitama, an urban city located in Japan. The volume-weighted mean concentration of total PAHs in rainwater samples (dissolved + particulate) was 108.8 ng L-1 with a range of 17.6-192.9 ng L-1. Two and three benzene ring PAHs were predominantly detected, occupying 67.0% of the total concentration in rainwater samples. Individual PAH concentrations were negatively correlated with their K-ow, suggesting that low-molecular-weight PAHs are preferentially scavenged owing to the higher hydrophilicity. The toxic equivalent calculated based on the relative potencies of individual PAHs showed high toxic contributions by chrysene and benz[a]anthracene in the rainwater samples. Those PAHs levels in rainwater were comparable or higher than those in adjacent river water. Correlation coefficient of PAH signatures between rainwater and surface water samples was high particularly in the dissolved phase, supporting the source/sink relationships of PAHs between wet deposition samples and receiving waters. The mean deposition flux of PAHs was 2000 ng m(-2) and considered to increase with precipitation amounts.
  TAYLOR & FRANCIS LTD, English, Scientific journal
  DOI：https://doi.org/10.1080/10406638.2021.1950781
  DOI ID：10.1080/10406638.2021.1950781, ISSN：1040-6638, eISSN：1563-5333, Web of Science ID：WOS:000678477900001
• Complete Decomposition of 2-Propanol Using TiO2 Immobilized on a Nonwoven Fabric Under UV Light Irradiation by Adding H2O2 and O-3 Microbubbles　　　　　　　　　　　　　　　
  Fumio Yasui; Kazuhiko Sekiguchi; Takeshi Yoshida; Kyung Hwan Kim; Hajime Tamura
  WATER AIR AND SOIL POLLUTION, Volume：232, Number：5, May 2021, [Reviewed]
  The degradation and mineralization of 2-propanol (IPA) in an aqueous solution were investigated using a TiO2 photocatalyst immobilized on a nonwoven fabric, both in the presence and absence of O-3 microbubbles and H2O2. The influence of parameters like the H2O2/O-3 molar ratio and the type of ultraviolet (UV) lamp used on the IPA degradation reaction was investigated. The main active species in IPA degradation and mineralization are thought to be hydroxyl radicals, generated as a consequence of the H2O2-O-3 (peroxone) reaction, the photolysis of H2O2 and O-3, and the TiO2-based photocatalytic reaction. The fastest IPA degradation rate was obtained under UV irradiation in the presence of H2O2, O-3, and TiO2 immobilized on a nonwoven fabric. Because under these conditions sufficient UV light is irradiated on the catalyst surface, we found that the optimum ratio for the peroxone reaction between O-3 and H2O2 did not change in our reaction system, even in the presence of the TiO2 immobilized nonwoven fabric. This means that the UV light contributes effectively to the photocatalytic reaction without interfering with the peroxone process, and that the photocatalyst does not only promote the decomposition of IPA but also the mineralization of the degradation products. We explored the influence of the base material used to manufacture the nonwoven fabric on the mineralization rate and found that the use of polyethylene terephthalate (instead of polyolefin fibers) to prepare the nonwoven fabric substantially accelerated the rates of the IPA, acetone, and total organic carbon decomposition reactions.
  SPRINGER INTERNATIONAL PUBLISHING AG, English, Scientific journal
  DOI：https://doi.org/10.1007/s11270-021-05106-2
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  DOI ID：10.1007/s11270-021-05106-2, ISSN：0049-6979, eISSN：1573-2932, SCOPUS ID：85104527400, Web of Science ID：WOS:000641853300003
• Characteristics of Chemical Components in Fine Particles (PM2.5) and Ultrafine Particles (PM0.1) in Hanoi, Vietnam: a Case Study in Two Seasons with Different Humidity　　　　　　　　　　　　　　　
  Truong Thi Huyen; Ryosuke Yamaguchi; Yuta Kurotsuchi; Kazuhiko Sekiguchi; Nghiem Trung Dung; Nguyen Thi Thu Thuy; Ly Bich Thuy
  WATER AIR AND SOIL POLLUTION, Volume：232, Number：5, May 2021, [Reviewed]
  The variations of the concentration and characteristics of particulate matter (PM) are influenced by several factors, such as emission sources and meteorological conditions. In this study, fine particles (PM2.5) and ultrafine particles (PM0.1) were simultaneously collected during summer and winter in Hanoi, Vietnam, to clarify the behavior of PM0.1 (which is rarely observed in this region) by characterizing the chemical components of each particle size in order to clarify particle formation and growth in two seasons with different humidity. The results showed that organic carbon (OC) and elemental carbon (EC) were the major compounds in both size ranges of PM, accounting for up to 56% and 80% of the analyzed components in PM2.5 and PM0.1, respectively. Secondary organic carbon (SOC) accounted for 36-41% and 37-47% of the total OC in PM2.5 and PM0.1, respectively, indicating an important contribution of secondary sources to OC. The strong correlations between water-soluble organic carbon (WSOC) and both sulfate (SO42-) and nitrate (NO3-) showed that photochemical reactions contributed considerably to WSOC formation. Furthermore, the correlations between absolute humidity and other chemical components suggest that the PM2.5 collected in Hanoi was formed by secondary processes in the aqueous phase on the aerosol surface. In contrast, no correlation was found between the relative humidity and other chemical components. These observations indicate that particle growth is dependent on the number of water molecules above a certain level under drizzle-like weather conditions particular to the study region, whereas occasional heavy rain during the sampling period might have hindered those processes.
  SPRINGER INTERNATIONAL PUBLISHING AG, English, Scientific journal
  DOI：https://doi.org/10.1007/s11270-021-05108-0
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85104747932&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85104747932&origin=inward
  DOI ID：10.1007/s11270-021-05108-0, ISSN：0049-6979, eISSN：1573-2932, SCOPUS ID：85104747932, Web of Science ID：WOS:000642902900001
• Removal of gaseous VOCs by ultrasonic irradiation of water　　　　　　　　　　　　　　　
  Akira Okada; Kazuhiko Sekiguchi; Kenshi Sankoda
  AIR QUALITY ATMOSPHERE AND HEALTH, Apr. 2021, [Reviewed]
  The decomposition of gaseous toluene as a representative volatile organic compound using 200 kHz ultrasonic waves was investigated as a new air cleaning method that does not require an ultraviolet light source, in accordance with the Minamata Convention on Mercury. Upon applying ultrasonic irradiation to water in a batch reactor, the removal ratio of gaseous toluene above the water reached 91.0% at 10 ppm and 92.7% at 40 ppm. The addition of t-BuOH, a radical scavenger that suppresses ultrasonic decomposition, inhibited the removal of gaseous toluene, indicating that the ultrasonic irradiation not only accelerated the dissolution of toluene into the water but also mediated its decomposition. Further experiments in a flow system revealed that the removal ratio of gaseous toluene decreased with increasing toluene flow rate, whereas the total mass of toluene removed increased, suggesting that sufficient amounts of the active species, such as (OH)-O-center dot radicals, required for the initial decomposition of toluene were formed in the liquid phase upon ultrasonic irradiation.
  SPRINGER, English, Scientific journal
  DOI：https://doi.org/10.1007/s11869-021-01026-6
  DOI ID：10.1007/s11869-021-01026-6, ISSN：1873-9318, eISSN：1873-9326, Web of Science ID：WOS:000642069000001
• The effects of meteorological conditions and long-range transport on PM2.5 levels in Hanoi revealed from multi-site measurement using compact sensors and machine learning approach　　　　　　　　　　　　　　　
  Bich-Thuy Ly; Yutaka Matsumi; Tuan V. Vu; Kazuhiko Sekiguchi; Thu-Thuy Nguyen; Chau-Thuy Pham; Trung-Dung Nghiem; Ich-Hung Ngo; Yuta Kurotsuchi; Thu-Hien Nguyen; Tomoki Nakayama
  JOURNAL OF AEROSOL SCIENCE, Volume：152, Feb. 2021, [Reviewed]
  Hanoi, the capital of Vietnam, frequently experiences heavy air pollution episodes in the winter, causing health concerns for the 7.5 million people living there. Spatial-temporal variations in PM2.5 levels can provide useful information about the sources and transportation of PM2.5. However, the published spatial-temporal data in the area are limited. In this research, PM2.5 concentrations at two sites in Hanoi and a site in Thai Nguyen (60 km north of Hanoi) were observed from October 2017 to April 2018, using newly available low-cost sensors. Hourly concentrations of PM2.5 at the three sites were similar on average (57.5, 54.9, and 53.6 mu g m(-3)) and clearly co-varied, suggesting remarkable large-scale effects. The contribution of long-range transport and meteorological factors on PM2.5 levels were investigated with a machine learning technique based on a random forest (RF) algorithm and concentration weight trajectory (CWT). The results showed that the contribution of long-range transport from the north and northeast to local PM2.5 levels was significant. Moreover, weather normalized PM2.5 concentrations and partial plots of meteorological factors on the levels of PM2.5 showed that meteorological conditions play a significant role in the formation of winter haze events.
  ELSEVIER SCI LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.jaerosci.2020.105716
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85096390035&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85096390035&origin=inward
  DOI ID：10.1016/j.jaerosci.2020.105716, ISSN：0021-8502, eISSN：1879-1964, SCOPUS ID：85096390035, Web of Science ID：WOS:000605112800004
• Capturing of gaseous and particulate pollutants into liquid phase by a water/oil column using microbubbles　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Fumio Yasui; Ema Fujii
  CHEMOSPHERE, Volume：256, Oct. 2020, [Reviewed]
  A new method was developed to remove gaseous and particulate pollutants by capturing them in water using microbubbles. The capture efficiency of gaseous toluene and ultrafine carbon particles, which are hydrophobic substances, was remarkably improved compared to water-only conditions by adding a small amount of oily substances (4% volume fraction of water) to the water surface. The physicochemical properties of four types of oily substances were investigated. Rapeseed and mineral oil exhibited good capture efficiency during a capture experiment of high-concentration gaseous toluene for 96 h. Additionally, a long-term continuous capture experiment for 24 days revealed that the capture mechanisms of rapeseed and mineral oil were different. The toluene concentration in rapeseed oil reached saturation in the middle of the experiment while the capture efficiency of mineral oil remained constant. It was also shown that the emulsion formation greatly affected the capture of rapeseed oil. Thus, it is expected that a new gaseous pollutant treatment technology that can capture and remove gaseous/particulate pollutants regardless of their hydrophilic/hydrophobic properties could be developed in the future. (C) 2020 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.chemosphere.2020.126996
  DOI ID：10.1016/j.chemosphere.2020.126996, ISSN：0045-6535, eISSN：1879-1298, Web of Science ID：WOS:000540870300012
• Chemical characterization and source apportionment of ambient nanoparticles: a case study in Hanoi, Vietnam　　　　　　　　　　　　　　　
  Trung-Dung Nghiem; Thi Thu Thuy Nguyen; Thi Thu Hien Nguyen; Bich-Thuy Ly; Kazuhiko Sekiguchi; Ryosuke Yamaguchi; Chau-Thuy Pham; Quoc Bang Ho; Minh-Thang Nguyen; Thanh Nam Duong
  ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, Volume：27, Number：24, First page：30661, Last page：30672, Aug. 2020, [Reviewed]
  PM(0.1)has been believed to have adverse short- and long-term effects on human health. However, the information of PM(0.1)that is needed to fully evaluate its influence on human health and environment is still scarce in many developing countries. This is a comprehensive study on the levels, chemical compositions, and source apportionment of PM(0.1)conducted in Hanoi, Vietnam. Twenty-four-hour samples of PM(0.1)were collected during the dry season (November to December 2015) at a mixed site to get the information on mass concentrations and chemical compositions. Multiple linear regression analysis was utilized to investigate the simultaneous influence of meteorological factors on fluctuations in the daily levels of PM0.1. Multiple linear regression models could explain about 50% of the variations of PM(0.1)concentrations, in which wind speed is the most important variable. The average concentrations of organic carbon (OC), elemental carbon (EC), water-soluble ions (Ca2+, K+, Mg2+, Na+, NH4+, Cl-, NO3-, SO42-, C2O42-), and elements (Be, Al, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sb, Ba, Tl, Pb, Na, Fe, Mg, K, and Ca) were 2.77 +/- 0.90 mu g m(-3), 0.63 +/- 0.28 mu g m(-3), 0.88 +/- 0.39 mu g m(-3), and 0.05 +/- 0.02 mu g m(-3), accounting for 51.23 +/- 9.32%, 11.22 +/- 2.10%, 16.28 +/- 2.67%, and 1.11 +/- 0.94%, respectively. A positive matrix factorization model revealed the contributions of five major sources to the PM(0.1)mass including traffic (gasoline and diesel emissions, 46.28%), secondary emissions (31.18%), resident/commerce (12.23%), industry (6.05%), and road/construction (2.92%).
  SPRINGER HEIDELBERG, English, Scientific journal
  DOI：https://doi.org/10.1007/s11356-020-09417-5
  DOI ID：10.1007/s11356-020-09417-5, ISSN：0944-1344, eISSN：1614-7499, Web of Science ID：WOS:000551572300078
• Corrigendum to “Effect of ultrasonic frequency on size distributions of nanosized mist generated by ultrasonic atomization” [Ultrason. Sonochem. 37 (2017) 16–22] (Ultrasonics - Sonochemistry (2017) 37 (16–22), (S1350417716304588), (10.1016/j.ultsonch.2016.12.019))　　　　　　　　　　　　　　　
  Takahisa Kudo; Kazuhiko Sekiguchi; Kenshi Sankoda; Norikazu Namiki; Susumu Nii
  Ultrasonics Sonochemistry, Volume：65, Jul. 2020, [Reviewed]
  The authors regret that there were some numerical errors in the sentences and figures. Therefore, the authors would like to make some changes to the paper for accuracy as below. 1. Correction of axis multipliers – Figure 2(b); ×105 → ×104– Figure 2(c); ×10 → ×103– Figure 3(c); ×10 → ×1032. Correction of numerical errors in the sentences – Page 17, Right column, Line 46; [25.5, 35.4, 49.0, 57.7, or 86.7 nm] → [30.4, 32.6, 49.0, 67.9, or 79.9 nm]– Page 17, Right column, Line 58; [80–200 nm] → [110–220 nm]– Page 17, Right column, Lines 60–61; [79.9, 120, 141, 181, or 212 nm] → [111, 130, 141, 181, or 212 nm]3. Corrected Figure 4 according to “2. Correction of numerical errors in the sentences” is shown below [Figure presented] The authors would like to apologise for any inconvenience caused.
  Scientific journal
  DOI：https://doi.org/10.1016/j.ultsonch.2020.105069
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85082995077&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85082995077&origin=inward
  DOI ID：10.1016/j.ultsonch.2020.105069, ISSN：1350-4177, eISSN：1873-2828, PubMed ID：32217060, SCOPUS ID：85082995077
• Secondary organic aerosol formation from p-dichlorobenzene under indoor environmental conditions　　　　　　　　　　　　　　　
  Sota Komae; Kazuhiko Sekiguchi; Megumi Suzuki; Ryoichi Nakayama; Norikazu Namiki; Naoki Kagi
  BUILDING AND ENVIRONMENT, Volume：174, May 2020, [Reviewed]
  In indoor environments, the formation of secondary organic aerosols (SOAs) from gaseous volatile organic compounds (VOCs), which may have adverse health effects, has attracted attention. In particular, 1,4-dichlombenzene (p-dichlorobenzene, p-DCB) is commonly used as a household insecticide in Japan, and its concentration may be high in indoor environments. Because p-DCB has highly reactive Cl groups, it is highly likely to be converted to SOAs under indoor environmental conditions. However, there have been no reports on the formation of SOAs from p-DCB. In this study, we investigated SOA formation from p-DCB gas under UV irradiation by volatilizing solid p-DCB and introducing it into a chamber as a gaseous substance, taking the influence of humidity and seed particles into account. Our results confirmed that SOAs, having a peak particle size of approximately 50 nm, were secondarily formed at a particle number concentration on the order of 10(12) m(-3) . In addition, increased humidity and the coexistence of (NH4)(2)SO4 particles as seed particles further accelerated SOA formation. Furthermore, in an experiment with low-intensity UV irradiation under general indoor environmental conditions, we confirmed that SOAs were formed with a number concentration on the order of 10(11) m(-3), which is higher than the concentration in the general atmosphere. Therefore, an SOA formation reaction from p-DCB could occur at sufficient levels, even in general indoor environments.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.buildenv.2020.106758
  DOI ID：10.1016/j.buildenv.2020.106758, ISSN：0360-1323, eISSN：1873-684X, Web of Science ID：WOS:000521983200005
• Improved ultrasonic degradation of hydrophilic and hydrophobic aldehydes in water by combined use of atomization and UV irradiation onto the mist surface　　　　　　　　　　　　　　　
  Yusei Ono; Kazuhiko Sekiguchi; Kenshi Sankoda; Susumu Nii; Norikazu Namiki
  Ultrasonics Sonochemistry, Volume：60, Jan. 2020, [Reviewed]
  © 2019 Elsevier B.V. Ultrasonic irradiation of 430 kHz, which induces both the chemical effect of pyrolysis and the physical effect of atomization, was carried out to achieve highly effective decomposition of organic substances in water with UV254 irradiation and H2O2 addition. To investigate the influence of physicochemical properties of the substrate on the degradation rate, three different aldehydes, namely, formaldehyde, acetaldehyde, and benzaldehyde, were selected as model substrates. Upon ultrasonic irradiation alone, the removal ratio of the hydrophobic substrate benzaldehyde reached 100% after 120 min, whereas the removal ratios of the hydrophilic substrates formaldehyde and acetaldehyde were only 21.1% and 53.0%, respectively. By combining ultrasonic atomization and UV254 irradiation, formaldehyde and acetaldehyde underwent effective gas-phase decomposition on the surfaces of the mist particles. Photolysis by UV254 irradiation mainly affected for the decomposition of aldehydes on the mist surface rather than the reaction of hydroxyl radicals derived from H2O2 made by water sonolysis. However, the addition of H2O2 effectively improved the decomposition and mineralization rates for both hydrophilic and hydrophobic aldehydes owing to the generation of hydroxyl radicals on the surfaces of the mist particles, which greatly contributed to the gas-phase decomposition. Consequently, the effective decomposition of organic pollutants was achieved regardless of their physicochemical properties in aqueous media.
  Scientific journal
  DOI：https://doi.org/10.1016/j.ultsonch.2019.104766
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85072164074&origin=inward
  DOI ID：10.1016/j.ultsonch.2019.104766, ISSN：1350-4177, eISSN：1873-2828, PubMed ID：31539724, SCOPUS ID：85072164074
• Decomposition of 2-Propanol in the Liquid Phase Using a Photocatalyst Immobilized on Nonwoven Fabric and Ozone Microbubbles　　　　　　　　　　　　　　　
  Fumio Yasui; Kazuhiko Sekiguchi; Hajime Tamura
  Water, Air, and Soil Pollution, Volume：230, Number：11, Nov. 2019, [Reviewed]
  © 2019, Springer Nature Switzerland AG. 2-Propanol (IPA) is a highly water-soluble volatile organic compound that is used in the cleaning and drying processes during semiconductor fabrication. IPA is also used as a disinfectant in the pharmacy field. Water scrubber processing is one of the methods used for IPA collection. However, water scrubbing requires wastewater treatment. In this study, we propose a decomposition system for IPA in the liquid phase based on a TiO2 photocatalyst immobilized on nonwoven fabric (TiO2 nonwoven fabric) and ozone microbubbles (MBs). The thick nonwoven fabric with immobilized TiO2 exhibits a higher IPA removal rate than that exhibited by the pleated fabric. IPA decomposes to produce acetone, which can be further decomposed and possibly undergo mineralization. The entire water tank can be supplied with ozone by introducing the MB-forming ozone, which considerably affects the decomposition of IPA. The efficient decomposition of IPA was achieved by combining ozone MBs, TiO2 nonwoven fabric, and ultraviolet irradiation, presumably because the photocatalyst promotes the mineralization of the decomposition product. Thus, the OH radicals from the O3 MBs competitively captured in the decomposition product strongly promote the decomposition of IPA, enhancing the IPA decomposition rate.
  SPRINGER INTERNATIONAL PUBLISHING AG, English, Scientific journal
  DOI：https://doi.org/10.1007/s11270-019-4292-9
  DOI ID：10.1007/s11270-019-4292-9, ISSN：0049-6979, eISSN：1573-2932, SCOPUS ID：85074230131, Web of Science ID：WOS:000499038600001
• Aqueous photochemical degradation of mefenamic acid and triclosan: role of wastewater effluent matrices　　　　　　　　　　　　　　　
  Sankoda Kenshi; Sugawara Yuta; Aida Takuya; Yamamoto Chieko; Kobayashi Jun; Sekiguchi Kazuhiko; Wang Qingyue
  WATER SCIENCE AND TECHNOLOGY, Volume：79, Number：10, First page：1853, Last page：1859, May 2019, [Reviewed]
  In this study, photochemical degradation of two emerging pharmaceutical chemicals, mefenamic acid (MF) and triclosan (TCS), was investigated to clarify the role of treated wastewater effluent matrices on their environmental photolysis. Target compounds were individually exposed to simulated sunlight in different media: ultrapure buffered water and synthetic field water with treated municipal wastewater effluent. The results in ultrapure buffered water showed that the direct photolysis processes in aquatic environments are not relevant to the elimination of MF. However, in samples containing treated wastewater effluent, photochemical degradation of MF was clearly enhanced. Our results indicate that MF undergoes indirect photolysis by reactive intermediates produced in an effluent matrix. Further quenching experiments suggested that photochemically produced hydroxyl radicals and excited triplet state dissolved organic matter drive the degradation of MF. In contrast to MF, TCS photochemical degradation proceeds through rapid direct photolysis. TCS was quickly degraded in ultrapure buffered water but it is considerably hampered in samples containing wastewater effluent. The declined degradation of TCS in the synthetic field water was discussed in terms of underlying optical filter effects by coexisting chromophoric substances. Results emphasize the importance of taking local water chemistry into consideration when predicting natural attenuation of pharmaceutical chemicals in receiving areas.
  IWA PUBLISHING, English, Scientific journal
  DOI：https://doi.org/10.2166/wst.2019.173
  DOI ID：10.2166/wst.2019.173, ISSN：0273-1223, eISSN：1996-9732, Web of Science ID：WOS:000476841100003
• Ambient PM2.5, polycyclic aromatic hydrocarbons and biomass burning tracer in Mae Sot District, western Thailand
  Radshadaporn Janta; Kazuhiko Sekiguchi; Ryosuke Yamaguchi; Khajornsak Sopajaree; Siwatt Pongpiachan; Thaneeya Chetiyanukornkul
  Atmospheric Pollution Research, Jan. 2019, [Reviewed]
  © 2019 Turkish National Committee for Air Pollution Research and Control Levoglucosan, as a biomass tracer, and sixteen polycyclic aromatic hydrocarbons (PAHs) in PM2.5 ambient air samples collected from Tak Province during smoke and non-smoke episodes were analyzed. The average PM2.5, levoglucosan and total PAHs concentrations in the smoke episode were 61.64 ± 22.85, 1.00 ± 0.41 μg/m3 and 6.32 ± 2.26 ng/m3, respectively. This figures were significantly higher than those recorded during the non-episode (13.76 ± 5.58, 0.12 ± 0.03 μg/m3 and 2.59 ± 0.15 ng/m3, respectively). The predominant PAHs proportions were comprised of Phenanthrene and Benzo[ghi]perylene and levoglucosan concentrations revealed a strong correlation with PM2.5 concentrations, which indicated the source of PM2.5 from biomass burning. Toxicity equivalent (TEQBaP) and the mutagenic equivalent (MEQBaP) levels during the smoke episode were significantly higher than those in the non-smoke episode. Furthermore, lifetime lung cancer risk recorded during smoke episode exceeded the acceptable cancer risk that has been recommended by US-EPA. These results suggest that this area was not only exposed to PAHs that originated from traffic combustion, but was also exposed from biomass burning emissions, particularly during biomass burning season when there is an increased risks of cancer and mutation. Although the exposure time in this area is relatively short, the high dose period of exposure occurs repetitively every year. In addition, backward trajectories showed that most of the air mass was generated from western region of Thailand and they were throughout the burning region not only emitted from local areas, but also from outside the country during the smoke episode.
  DOI：https://doi.org/10.1016/j.apr.2019.09.003
  DOI ID：10.1016/j.apr.2019.09.003, ISSN：1309-1042, SCOPUS ID：85074385453
• Dynamics of dissolved organic matter in a wastewater effluent-impacted Japanese urban stream: characteristics, occurrence and photoreactivity of fluorescent components　　　　　　　　　　　　　　　
  Sankoda Kenshi; Yamamoto Chieko; Sekiguchi Kazuhiko; Kobayashi Jun; Wang Qingyue
  WATER SCIENCE AND TECHNOLOGY, Volume：78, Number：10, First page：2036, Last page：2045, Dec. 2018, [Reviewed]
  We report the results of using the excitation-emission matrix (EEM) method combined with parallel factor analysis (PARAFAC) to investigate the characteristics and occurrence of dissolved organic matter (DOM) in an urban stream impacted by effluent from a wastewater treatment plant (WWTP). The PARAFAC model divides the bulk EEM spectra into six individual fluorescent components with three humic-like components (C1-C3), two protein-like components (C4 and C5) and a wastewater-derived component (C6). In general, intensities of fluorescent components are abundant in WWTP effluent impacted samples, thus showing that such an effluent is a major source of DOM in urban rivers, but C5 is considered to have autochthonous sources within the stream. In areas where the effluent is released, the fluorescent intensity from components (except C5) gradually decreases as these components are transported downstream. However, concentrations of dissolved organic carbon remain almost constant downstream of the release area. These results would be attributed to degradation and/or modification of fluorophore. Photolysis experiments confirmed that fluorescent intensities can decrease with increase of irradiation times. C6 particularly showed a rapid photodegradation, remaining only 24.1% after 48 h photolysis. These findings would be important when assessing DOM source and water quality in aquatic environments by EEM-PARAFAC.
  IWA PUBLISHING, English, Scientific journal
  DOI：https://doi.org/10.2166/wst.2018.468
  DOI ID：10.2166/wst.2018.468, ISSN：0273-1223, eISSN：1996-9732, Web of Science ID：WOS:000457673100002
• Measurements of the Size and Composition of Volatile Particles Generated from a Heated Tobacco Product with Aerosol Fixation Agents　　　　　　　　　　　　　　　
  Ishikawa Nobuyuki; Sekiguchi Kazuhiko
  AEROSOL AND AIR QUALITY RESEARCH, Volume：18, Number：10, First page：2538, Last page：2549, Oct. 2018, [Reviewed]
  DOI：https://doi.org/10.4209/aaqr.2018.02.0049
  DOI ID：10.4209/aaqr.2018.02.0049, ISSN：1680-8584, Web of Science ID：WOS:000445921200003
• Mass Concentrations and Carbonaceous Compositions of PM0.1, PM2.5, and PM10 at Urban Locations in Hanoi, Vietnam　　　　　　　　　　　　　　　
  Nguyen Thi Thu Thuy; Nghiem Trung Dung; Sekiguchi Kazuhiko; Ly Bich Thuy; Nguyen Thi Thu Hien; Yamaguchi Ryosuke
  AEROSOL AND AIR QUALITY RESEARCH, Volume：18, Number：7, First page：1591, Last page：1605, Jul. 2018, [Reviewed]
  DOI：https://doi.org/10.4209/aaqr.2017.11.0502
  DOI ID：10.4209/aaqr.2017.11.0502, ISSN：1680-8584, Web of Science ID：WOS:000435943400007
• Size distribution and sources of 37 toxic species of particulate polycyclic aromatic hydrocarbons during summer and winter in Baoshan suburban area of Shanghai, China (Retraction of Vol 566, Pg 1519, 2016)　　　　　　　　　　　　　　　
  Wang Qingyue; Kobayashi Keisuke; Wang Weiqian; Ruan Jie; Nakajima Daisuke; Yagishita Mayuko; Lu Senlin; Zhang Wenchao; Suzukia Miho; Saitou Tomoya; Sekiguchi Kazuhiko; Sankoda Kenshi; Takao Yuji; Nagae Masaki; Terasaki Masanori
  SCIENCE OF THE TOTAL ENVIRONMENT, Volume：626, First page：1507, Last page：1507, Jun. 2018, [Reviewed]
  ELSEVIER SCIENCE BV, English
  DOI：https://doi.org/10.1016/j.scitotenv.2018.02.158
  DOI ID：10.1016/j.scitotenv.2018.02.158, ISSN：0048-9697, eISSN：1879-1026, Web of Science ID：WOS:000428194000149
• Combined sonochemical and short-wavelength UV degradation of hydrophobic perfluorinated compounds　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Takahisa Kudo; Kenshi Sankoda
  ULTRASONICS SONOCHEMISTRY, Volume：39, First page：87, Last page：92, Nov. 2017, [Reviewed]
  Perfluorochemicals (PFCs), which are common in the aquatic environment, are toxic substances that have high chemical and heat resistance because of their strong C-F bonds. We investigated the effect of ultrasonication and short-wavelength UV irradiation on the degradation of perfluorooctane, perfluoropropionic acid, and perfluorooctanoic acid, which are examples of hydrophobic, hydrophilic, and intermediate PFCs, respectively. The results confirmed that ultrasonication was more effective for decomposing hydrophobic PFCs and UV irradiation was more effective for decomposing hydrophilic PFCs. Therefore, defluorination of the degradation intermediates was improved by a combination of ultrasonication and UV irradiation. Our results can be applied to the decomposition treatment of PFCs that have various levels of water solubility in the aquatic environment.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.ultsonch.2017.04.002
  DOI ID：10.1016/j.ultsonch.2017.04.002, ISSN：1350-4177, eISSN：1873-2828, Web of Science ID：WOS:000407185600010
• Ozone Catalytic Oxidation of Gaseous Toluene over MnO2-Based Ozone Decomposition Catalysts Immobilized on a Nonwoven Fabric　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Yuki Kurita; Kenshi Sankoda; Norikazu Namiki; Fumio Yasui; Hajime Tamura
  AEROSOL AND AIR QUALITY RESEARCH, Volume：17, Number：8, First page：2110, Last page：2118, Aug. 2017, [Reviewed]
  Degradation of toluene gas by ozone catalytic oxidation (OZCO) by using a MnO2-based ozone decomposition catalyst (ODC) was investigated to clarify the reactive site of ODC material with O-3. An optimum structure for the ODC to remove O-3 and toluene were proposed. For honeycomb ODC, toluene degradation by OZCO occurred only around the entrance of the honeycomb ODC, and we expected that a thinner ODC would increase the toluene degradation efficiency. A nonwoven fabric on which ODC was immobilized was developed to decompose O-3 and volatile organic compounds simultaneously. The toluene degradation ratio and the mineralization of toluene to CO2 were determined to evaluate the performance of the fabric. Furthermore, the effects of relative humidity and O-3 concentration on the decomposition and mineralization ratios were also investigated with or without 254 nm UV irradiation (UV254). The fabric decomposed and mineralized toluene to CO2, even at low O-3 concentrations. Although high humidity reduced the degradation ratio of toluene, UV254 irradiation improved the recovery of the degradation ratio and increased the mineralization ratio.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2017.01.0045
  DOI ID：10.4209/aaqr.2017.01.0045, ISSN：1680-8584, eISSN：2071-1409, Web of Science ID：WOS:000408055500015
• Effect of ultrasonic frequency on size distributions of nanosized mist generated by ultrasonic atomization　　　　　　　　　　　　　　　
  Takahisa Kudo; Kazuhiko Sekiguchi; Kenshi Sankoda; Norikazu Namiki; Susumu Nii
  ULTRASONICS SONOCHEMISTRY, Volume：37, First page：16, Last page：22, Jul. 2017, [Reviewed]
  Ultrasonic atomization is used to produce fine liquid mists with diameter ranges below 100 nm. We investigated the effect of the frequency on the size distribution of ultrasonic mist. A bimodal distribution was obtained for the mist generated by ultrasonic atomization with a wide-range particle spectrometer. The peak diameter decreased with increasing frequency, and the number concentration of the mist increased in the smaller range. We determined the relation between the size distribution of the mist and the ultrasonic frequency, and we proposed a generation mechanism for the ultrasonic nanosized mist based on the amount of water vapor around the liquid column. Increasing the power intensity and density by changing the surface diameter of the ultrasonic oscillator affected the number concentration and size distribution of the nanosized mist. Using this technique, the diameter of the mist can be controlled by changing the frequency of the ultrasonic transducer. (C) 2016 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.ultsonch.2016.12.019
  DOI ID：10.1016/j.ultsonch.2016.12.019, ISSN：1350-4177, eISSN：1873-2828, Web of Science ID：WOS:000403120900004
• Aqueous secondary formation of brominated, chlorinated, and mixed halogenated pyrene in presence of halide ions　　　　　　　　　　　　　　　
  Kenshi Sankoda; Izumi Toda; Kazuhiko Sekiguchi; Kei Nomiyama; Ryota Shinohara
  CHEMOSPHERE, Volume：171, First page：399, Last page：404, Mar. 2017, [Reviewed]
  We examined the secondary production of halogenated derivatives of polycyclic aromatic hydrocarbons (PAHs) in surface seawater. Pyrene was selected as the model compound and exposed to UV irradiation in synthetic seawater for various irradiation times. Pyrene underwent rapid photochemical reactions that produced various halogenated derivatives including 1-chloropyrene, 1-bromopyrene, three unidentified dichloropyrenes, and three unidentified bromochloropyrenes. The production of 1-chloropyrene (220-360 nM) was higher than that of 1-bromopyrene (7.3-12 nM), reflecting the high chlorine content of seawater. A pilot field survey was conducted to test the environmental implications of these results, and fresh, brackish, and seawater samples were collected in southwestern Japan. The variation in the concentration ratios between 1-chloropyrene and pyrene implied the presence of a specific source of 1-chloropyrene in coastal water, which can be partly explained by the secondary production observed in our photolysis experiments. In sum, the photochemical reactions of PAHs are a potential secondary source of halogenated PAHs, especially in marine environments heavily contaminated with PAHs. (C) 2016 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.chemosphere.2016.12.044
  DOI ID：10.1016/j.chemosphere.2016.12.044, ISSN：0045-6535, eISSN：1879-1298, Web of Science ID：WOS:000393931100047
• Size distribution of allergenic Cry j 2 released from airborne Cryptomeria japonica pollen grains during the pollen scattering seasons　　　　　　　　　　　　　　　
  Xiumin Gong; Qingyue Wang; Senlin Lu; Miho Suzuki; Daisuke Nakajima; Kazuhiko Sekiguchi; Makoto Miwa
  AEROBIOLOGIA, Volume：33, Number：1, First page：59, Last page：69, Mar. 2017, [Reviewed]
  Japanese cedar (Cryptomeria japonica) pollinosis is one of seasonal allergic rhinitis that mainly occurs in Japan. The pollinosis is caused by two main kinds of allergenic proteins called Cry j 1 and Cry j 2 which exist in Cryptomeria japonica pollen. In our previous study, we reported that the size-segregated of airborne fine allergenic Cry j 1 and morphological change of Cry j 1 due to the contact with rainfall. However, the study on airborne allergenic Cry j 2 in different particle sizes has not been identified until now. Therefore, the main aim of this study is to investigate the size distribution and scattering behavior of allergenic Cry j 2. The Cry j 2 particles were collected and determined in different particle sizes at the urban sampling points during the most severe pollination season of 2012 in Saitama, Japan. After the size-segregated Cry j 2 allergenic particles were collected using an Andersen high-volume (AHV) atmospheric sample, the airborne Cry j 2 concentrations were determined with a surface plasmon resonance (SPR) method. At the same time, the airborne Cryptomeria japonica pollens were also counted by the Durham pollen sampler. The higher concentrations of the allergenic Cry j 2 were detected even in particle sizes equal to or less than 1.1 mu m (PM1.1) than other particle sizes. The airborne particles ranges from 0.06 to 11 mu m were also collected by a low-pressure impactor (LPI) atmospheric sampler. After that, the concentrations of Cry j 2 allergenic particles in fine particle sizes were measured by the SPR method either. With the help of this study, we have confirmed the existence of fine daughter allergenic particles, which clearly differ from the parent pollen grains in size, especially after the rainy days. It is possible that the daughter allergenic species will be released from the fractions of cell wall and burst pollen grains. We concluded that rainwater was one of the important factors that affects the release of pollen allergenic proteins of both Cry j 1 and Cry j 2 from the parent pollen grains.
  SPRINGER, English, Scientific journal
  DOI：https://doi.org/10.1007/s10453-016-9450-6
  DOI ID：10.1007/s10453-016-9450-6, ISSN：0393-5965, eISSN：1573-3025, Web of Science ID：WOS:000394353400006
• Influence of volatilization from mainstream tobacco smoke particles on the gas-particle distribution in annular denuders　　　　　　　　　　　　　　　
  Nobuyuki Ishikawa; Kazuhiko Sekiguchi
  AEROSOL SCIENCE AND TECHNOLOGY, Volume：51, Number：5, First page：642, Last page：652, 2017, [Reviewed]
  The influence of volatilization from mainstream tobacco smoke particles in annular denuders on the gas-particle distribution was investigated by using multiple annular denuders coupled with a filter pack method (multiple-AD-FP method) under low flow volume conditions (1.05 and 1.65L/min). Smoking experiments and model experiments using poly styrene latex (PSL) particles and generated gases were conducted to measure the particle loss ratio and gas collection efficiency in the denuders. In this research, we focused on the influence of XAD-4 slurry concentrations and particle volatility including tobacco smoke from a cigarette and vapor products on the volatilization from particles in the denuders, and have proposed a measurement method for considering volatilization. Our experimental results showed that volatilization depends on the particle volatility, targeted components, denuder length, particle concentration, and adsorbent amount, thereby suggesting the importance of selecting the proper measurement conditions and taking volatilization into account, so as to evaluate the appropriate gas-particle distribution. The gas-phase nicotine ratio obtained from calculating the volatilization rate in the multiple-AD-FP method agreed with previous research. This means that the calculation method was appropriate for the evaluation of gas-particle distribution. Furthermore, the gas-particle ratio determined through the multiple-AD-FP method was compared to that determined through a filter-impinger method that uses a glass fiber filter. The results revealed that most of the gases in the filter-impinger method were not collected in the impinger due to the condensation of gases on the surface of the filter fibers and collected particles.(c) 2017 American Association for Aerosol Research
  TAYLOR & FRANCIS INC, English, Scientific journal
  DOI：https://doi.org/10.1080/02786826.2017.1290213
  DOI ID：10.1080/02786826.2017.1290213, ISSN：0278-6826, eISSN：1521-7388, Web of Science ID：WOS:000399555900009
• Evaluation of Artifacts Generated during Collection of Ultrafine Particles Using an Inertial Filter Sampler　　　　　　　　　　　　　　　
  Hirotoshi Kuwabara; Kazuhiko Sekiguchi; Kenshi Sankoda; Kenji Sakurai; Ryosuke Yamaguchi; Masami Furuuchi; Mitsuhiko Hata
  AEROSOL AND AIR QUALITY RESEARCH, Volume：16, Number：12, First page：3063, Last page：3074, Dec. 2016, [Reviewed]
  Two artifacts were observed during collection of atmospheric ultrafine particles (UFPs; < 100 nm diameter) using an inertial filter (INF) sampler recently developed for this purpose. These artifacts were evaluated. First, the adsorption of organic and ionic gas onto a quartz fiber filter installed in the INF sampler was evaluated to provide information on the positive artifact; this information is important for accurate analysis of the UFP components. Gas adsorption by the INF sampler was similar to or less than that of other devices for collecting UFPs. The gas adsorption of organic carbon (OC) fractions, and ionic components of NH4+, NO3- and SO42- was confirmed, and the adsorption of OC1 and ionic components were highly dependent on the concentration of the gas and the UFP concentration under ambient conditions. These results suggest that it is necessary to know the concentration of the UFPs on the filter in order to evaluate the exact concentrations of UFP components under high flow rate conditions. Second, the efficiency of UFP collection on a polytetrafluoroethylene (PTFE) filter installed in the INF sampler was evaluated to clarify the negative artifact. The data confirmed that the efficiency of collection changed with changing structure such as pore size, porosity and thickness of the filter. The structure of these filters and UFPs collected on there were observed by a scanning electron microscopy. The highest particle collection efficiency (almost 100%) was obtained by installing two thick membrane PTFE filters. The collection of UFPs using a sampler comprising several filter stages is a convenient and useful method for evaluating positive and negative artifacts and for quantifying the concentration of components of UFPs.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2015.12.0679
  DOI ID：10.4209/aaqr.2015.12.0679, ISSN：1680-8584, eISSN：2071-1409, Web of Science ID：WOS:000392308000008
• Size distribution and sources of 37 toxic species of particulate polycyclic aromatic hydrocarbons during summer and winter in Baoshan suburban area of Shanghai, China　　　　　　　　　　　　　　　
  Qingyue Wang; Keisuke Kobayashi; Weiqian Wang; Jie Ruan; Daisuke Nakajima; Mayuko Yagishita; Senlin Lu; Wenchao Zhang; Miho Suzuki; Tomoya Saitou; Kazuhiko Sekiguchi; Kenshi Sankoda; Yuji Takao; Masaki Nagae; Masanori Terasaki
  SCIENCE OF THE TOTAL ENVIRONMENT, Volume：566, First page：1519, Last page：1534, Oct. 2016, [Reviewed]
  The objectives of this study were to assess the size-segregated distribution and sources of 37 different species of particulate polycyclic aromatic hydrocarbons (PAHs) in a suburban area of Shanghai metropolitan City, China. The ambient particulate sampling was carried out on the rooftop of a five-stories building in Baoshan campus of Shanghai University. An Andersen high-volume air sampler was employed to collect ambient size-segregated particulate matter during summer of August to September and winter of November to December 2015. The high toxic PAHs were determined by a gas chromatography mass spectrometry. The concentrations of total PAHs in suspended particulate matter (SPM) and PM1.1 (suspended particulate matter below 1.1 mu m in diameter) in the suburban area of Shanghai were 4.58-14.5 ng/m(3) and 1.82-8.56 ng/m(3), respectively in summer, and 43.6-160 ng/m(3) and 23.2-121 ng/m(3), separately in winter. 1,8-Naphthalic anhydride (1,8-NA) showed the highest concentration among 37 different species of PAHs in the suburban area of Shanghai. The concentrations of high molecular PAHs (e.g. 5-6 ring PAHs) followed a nearly unimodal size distribution with the highest peaks in PM1.1. The diagnostic ration qualitatively indicated that PAHs in SPM of Shanghai were mainly derived from motor-vehicle or petroleum combustion in summer and from coal and biomass combustion in winter. According to the calculated toxicity equivalency factors based on the methods of Nisbet and Lagoy and the potency equivalency factors (PEF) recommended by U.S. EPA, the highest contributors in the total carcinogenicity of the PAHs in SPM and PM1.1 were dibenzo[a,h] pyrene (46.2% and 45.0% in summer), benzo[a] pyrene (44.4% and 43.8% in winter) and benz[j] aceanthrylene (80.2% and 83.1% in summer and 83.1% and 84.0% in winter), respectively. Therefore, benzo[a] pyrene seemed to be a lower contributor than other carcinogenic PAHs. (C) 2016 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.scitotenv.2016.06.039
  DOI ID：10.1016/j.scitotenv.2016.06.039, ISSN：0048-9697, eISSN：1879-1026, Web of Science ID：WOS:000381060900146
• Studies on size distribution and health risk of 37 species of polycyclic aromatic hydrocarbons associated with fine particulate matter collected in the atmosphere of a suburban area of Shanghai city, China　　　　　　　　　　　　　　　
  Qingyue Wang; Keisuke Kobayashi; Senlin Lu; Daisuke Nakajima; Weiqian Wang; Wenchao Zhang; Kazuhiko Sekiguchi; Masanori Terasaki
  ENVIRONMENTAL POLLUTION, Volume：214, First page：149, Last page：160, Jul. 2016, [Reviewed]
  Polycyclic aromatic hydrocarbons (PAHs) in suspended particulate matter (SPM) contribute significantly to health risk. Our objectives were to assess the size distribution and sources of 26 PAHs and 11 polycyclic aromatic compounds (PACs) in SPM in the suburban area, Shanghai city, China. Air sampling was carried out on the rooftop of a five-stories building in the campus of Shanghai University. An Andersen high-volume air sampler was employed to collect ambient size-segregated particles from August to September 2015. The toxic particulate PAHs were determined by the gas chromatography mass spectrometry. The concentrations of total PAHs (TPAHs) in SPM and PM1.1 (suspended particulate matter below 1.1 mu m) were in the ranges of 4.58-14.5 ng m(-3) and 1.82-8.56 ng m(-3), respectively. 1,8-naphthalic anhydride showed the highest concentrations among 37 species of PAHs and PACs ranging 7.76 -47.9 ng m(-3) and 1.50-17.6 ng m(-3) in SPM and PM1.1, respectively. The concentrations of high molecular weight 5-6 ring PAHs followed a nearly unimodal size distribution with the highest peak in PM1.1, while other lower molecular weight PAHs were not dependent on particle sizes. The toxicity analysis indicated that the carcinogenic potency of particulate PAHs primarily existed in PM1.1. Regarding meteorological parameters and other pollutants, the positive effect of humidity and NO2 over PAHs was confirmed. Diagnostic ration indicated that the particulate PAHs in Shanghai were mainly derived from motor vehicle or petroleum combustion. The highest benzo[a]pyrene equivalent (BaPeq) in SPM and PM1.1 were 2.15 ng M-3 and 1.43 ng m(-3) calculated by the toxicity equivalency factor, and 69.31 ng m(-3) and 47.81 ng M-3 estimated by the potency equivalency factors, respectively. The highest contributors in the total carcinogenicity of the particulate PAHs were dibenzo[a,h]pyrene (46.2% and 45.0%) and benz[j] aceanthrylene (80.2% and 83.1%), respectively while benzo[a]pyrene is lower contributor than other carcinogenic PAHs. (C) 2016 Elsevier Ltd. All rights reserved.
  ELSEVIER SCI LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.envpol.2016.04.002
  DOI ID：10.1016/j.envpol.2016.04.002, ISSN：0269-7491, eISSN：1873-6424, Web of Science ID：WOS:000378448600017
• Experimental study on mechanical filtration through tobacco columns: Influence of cut-filler shape and size distribution on filtration efficiencies　　　　　　　　　　　　　　　
  Nobuyuki Ishikawa; Kazuhiko Sekiguchi
  AEROSOL SCIENCE AND TECHNOLOGY, Volume：50, Number：5, First page：521, Last page：533, May 2016, [Reviewed]
  Tobacco columns are extreme examples of heterogenous packed beds, which have various cut-filler shapes and a wide range of size distribution. The behavior of mechanical filtration through tobacco columns has been investigated by using polystyrene latex (PSL) standard particles to compare the actual filtration efficiency with the predicted filtration efficiency calculated by theoretical equations for spherical packed beds. The influence of cut-filler shape and the range of cut-filler size distribution on filtration efficiency have been examined. The effect of diffusion in tobacco columns was lower and the effect of interception and inertia were higher than in spherical packed beds. These results show that a partially faster flow could have occurred in tobacco columns. It means that it is difficult to utilize the theoretical equations for spherical packed beds to heterogenous packed beds as proposed. Filtration efficiency through tobacco columns had a relationship with the factor that shows cut-filler shape and size distribution (r = 0.894, p < 0.05) and the factor that shows cut-filler size distribution (r = 0.683, p < 0.15). The factor showing cut-filler shape and size distribution was expected to be an effective factor of filtration efficiency for heterogenous packed beds. From these experiments, empirical equations that can be applied to tobacco columns have been proposed, and the prediction accuracy during burning was validated. It has been found that the prediction accuracy was precise, revealing the importance of taking the influence of cut-filler shape and size distribution into account in the filtration equations.
  TAYLOR & FRANCIS INC, English, Scientific journal
  DOI：https://doi.org/10.1080/02786826.2016.1166174
  DOI ID：10.1080/02786826.2016.1166174, ISSN：0278-6826, eISSN：1521-7388, Web of Science ID：WOS:000374667600003
• Carbonaceous Components in PM2.5 and PM0.1 with Online Measurements of Gaseous and Particulate Pollutants: Implication of Thermal-Optical Derived EC2 Fraction as a Component of Ultrafine Particles in the Roadside Environment　　　　　　　　　　　　　　　
  Kyung Hwan Kim; Sung Ho Woo; Seung-Bok Lee; Gwi-Nam Bae; Kazuhiko Sekiguchi; Ryota Kobayashi; Motomi Kamiyama
  AEROSOL AND AIR QUALITY RESEARCH, Volume：16, Number：2, First page：361, Last page：372, Feb. 2016, [Reviewed]
  An investigation of the carbonaceous components of PM2.5 (D-p < 2.5 mu m) and PM0.1 (D-p < 0.1 mu m) in conjunction with online measurements of gaseous and particulate pollutants, which are dominated by motor vehicle emissions, was undertaken over 15 consecutive days in a field sampling campaign at a roadside and reference site for daytime (06: 00 to 17: 30) and nighttime (18: 00 to 05: 30) conditions. The results indicated that traffic-related air pollutants strongly influenced pollution levels in the sampling area, especially during the nighttime, although the concentrations were lower than during the daytime. Water-soluble organic carbon/organic carbon (WSOC/OC) ratios in PM0.1 were 0.60 +/- 0.11 and 0.63 +/- 0.16 at the roadside and reference sites, respectively, while the corresponding ratios in PM2.5 were found to be 0.60 +/- 0.11 and 0.63 +/- 0.14. These results demonstrated the relatively high contribution of WSOC in the study area compared to in previous reports. It was observed that elemental carbon (EC) in PM0.1 are emitted approximately by a factor of 0.1 in comparison with those observed for EC in PM2.5 when considering the slopes of the linear relationship with particle-bound PAHs and NOx, while OC displayed no such relationship. Our measurements indicate that a significant portion of the OC in PM0.1 is not directly co-emitted with EC from motor vehicles but is readily adsorbed or condensed onto the existing EC fractions through condensation. The relationship between the EC2 fraction and the particle number concentration indicates that the EC2 fraction is the primary chemical component of traffic related ultrafine particles in terms of particle number concentration.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2014.10.0266
  DOI ID：10.4209/aaqr.2014.10.0266, ISSN：1680-8584, eISSN：2071-1409, Web of Science ID：WOS:000369914300006
• Characterization of liquefied waste bamboo and white-rotted wood
  Q. Wang; H. Takahashi; Y. Takahashi; H. Kurokawa; K. Sekiguchi; K. Sugiyama
  WIT Transactions on Ecology and the Environment, Volume：195, First page：63, Last page：74, Jan. 2015
  © 2015 WIT Press. Due to the depletion of fossil fuel resources, the utilization of sustainable and renewable biomass is studied in various fields. Wood liquefaction is one of the applicable methods for material utilization of waste biomass. In this study, valueless waste bamboo and white-rotted wood were liquefied for reuse as an alternative plastic material. The waste bamboo samples were liquefied in polyethylene glycol (PEG) with sulfuric acid as a catalyst. Then, the molecular weight distribution of the contents of the liquefied bamboo samples was analyzed using gel permeation chromatography (GPC) and the residue mass was also measured in order to investigate the residue contents. At the same time, the whiterotted woody samples were liquefied in phenol with sulfuric acid as a catalyst. Rotted woody samples and liquefied contents were analyzed with X-ray diffraction (XRD) and determined by GPC, and the residue contents were also compared with the results of non-rotted woody samples. The waste bamboo samples were liquefied effectively under the reaction conditions of a temperature of 150°C, the acidic catalyst of 12% H 2 SO 4 and 1/4 proportion of bamboo samples to solvent, respectively. The residue contents were the lowest at a reaction time of 30 minutes, and after that they were increased a reaction progressed. With the help of GPC analysis, it was found that the peaks of the contents of the liquefied bamboo samples at the initial reaction stage appeared at a high molecular weight distribution, which disappeared when the reaction progressed. When the white-rotted woody samples were liquefied, due to the low powder density, the samples did not perform well at the initial reaction stage. From GPC analysis of the liquefied contents, the liquefied tendency and the residue contents of the white-rotted woody samples seemed to be almost the same as those of the non-rotted original woody samples.
  DOI：https://doi.org/10.2495/ESUS150061
  DOI ID：10.2495/ESUS150061, ISSN：1746-448X, SCOPUS ID：85063842030
• Study on the size-segregated distribution of 37 species of polycyclic aromatic hydrocarbons in urban atmospheric fine particles of Japan
  Q. Wang; K. Kobayashi; M. Zhou; S. Lu; S. Dong; D. Nakajima; K. Sekiguchi; M. Terasaki
  WIT Transactions on Ecology and the Environment, Volume：183, First page：131, Last page：143, Jul. 2014
  © 2014 WIT Press. The size-segregated distribution and seasonal concentrations of polycyclic aromatic hydrocarbons (PAHs) in urban suspended particulate matter (SPM) at the Japan national route 463 in the urban of Saitama city, Japan were investigated using an Andersen high-volume air sampler. Air sampling was carried out from June 2013 to January 2014. 37 species of toxic PAHs such as benzo[j]aceanthrylene, dibenzo[a,h]anthracene, benzo[c]fluorene and dibenzo[a,l]pyrene were measured. It was found that the average concentration of 37 species of particulate PAHs including methyl-PAHs, benzothiophenes and oxy-PAHs from atmospheric oxidation of PAHs collected in the urban of Saitama city was 3.42 to 6.51 ng/m3 during 2013 sampling campaign periods. 1,8-naphthalic anhydride (1,8-NA) showed the highest concentration among 37 species of PAHs. The concentrations of high molecular PAHs, which were found in all seasons, followed different size distribution, especially with the highest peak in fine particle sizes around 1.1 μm. The concentrations of low-molecular PAHs were not much different with particle sizes. The toxicity analysis indicated that the carcinogenic potency of particulate PAHs primarily existed in the particle size below 1.1 μm. 37 species of PAHs in urban atmospheric fine particles were not only derived from vehicle emission with long range transportation, but also produced by local other anthropogenic sources.
  DOI：https://doi.org/10.2495/AIR140111
  DOI ID：10.2495/AIR140111, ISSN：1743-3541, SCOPUS ID：84924079392
• 過酸化水素含有ミストを用いたVOCガス分解処理プロセスの開発　　　　　　　　　　　　　　　
  並木孝招; 関口和彦; 王 青躍; 並木則和; 東 賢一; 田村 一; 諏訪好英; 鍵 直樹; 藤井修二
  Volume：29, Number：2, First page：112, Last page：118, Jun. 2014, [Reviewed]
  Japanese, Scientific journal
  DOI：https://doi.org/10.11203/jar.29.112
  DOI ID：10.11203/jar.29.112
• Effective liquid-phase photocatalytic reaction using a newly developed titanium oxide-assisted reactor with ozone microbubble treatment　　　　　　　　　　　　　　　
  Kyung Hwan Kim; Kazuhiko Sekiguchi; Takeshi Yoshida; Fumio Yasui; Hajime Tamura
  SEPARATION AND PURIFICATION TECHNOLOGY, Volume：126, First page：15, Last page：20, Apr. 2014, [Reviewed]
  We have developed a TiO2-assisted reactor that improved the UV light penetration into the solution during the photocatalytic decomposition of isopropyl alcohol (IPA). Increasing the UV penetration enhanced the decrease in the concentration of acetone, which is the main IPA decomposition product, and the total organic carbon. However, it did not affect the decrease in IPA concentration. Charging the solution with O-3 microbubbles significantly increased mineralization for the first 5 h of the reaction. Our results can be used to improve the efficiency of UV sources and develop an ecologically friendly, practical wastewater treatment for IPA. (C) 2014 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.seppur.2014.02.010
  DOI ID：10.1016/j.seppur.2014.02.010, ISSN：1383-5866, eISSN：1873-3794, Web of Science ID：WOS:000335112400003
• Behavior of Chemical Components in PM_0.1 and PM_2.5 Transported from Roadside to Background Sites　　　　　　　　　　　　　　　
  SEKIGUCHI Kazuhiko; KINOSHITA Masatoshi; SAKURAI Kenji; Hwan KIM Kyung; WANG Qingyue; HAGINO Hiroyuki
  Earozoru Kenkyu, Volume：29, Number：1, First page：s55, Last page：s65, 2014
  This study utilized an inertial filter (INF) sampler to evaluate gas adsorption and chemical components in ultrafine particles (Dp < 0.1 μm; PM_0.1). They were measured at suburban roadside and background sites under low conditions of PM vaporization and gas adsorption and compared with the components of fine particles (Dp < 2.5 μm; PM_2.5). Atmospheric samplings of PM_0.1 and PM_2.5 were performed in summer and winter with 11.5 h sampling durations to observe the variation of chemical components between daytime and nighttime and to clarify the emission sources and the growth behavior of PM_0.1to PM_2.5. It was shown that the main components in PM_0.1 and PM_2.5 were different. Carbonaceous components at both sites accounted for 70 % in PM_0.1 and for 40 % in PM_2.5 respectively, because ionic components were dominant in PM_2.5. The carbonaceous and ionic components near the roadside in PM_0.1 had a tendency to be transported to background sites as they expanded via heterogeneous nucleation, especially in winter. Ultrafine particles with a diameter of 20-30 nm and OC1 fraction in OC components were confirmed only in winter, and OC1 fraction indicated higher correlation with soot EC components at both sites. Therefore, it was thought that OC1 fraction was emitted from the diesel exhaust and played an important role in the growth of PM_0.1 to PM_2.5.
  Japan Association of Aerosol Science and Technology, Japanese
  DOI：https://doi.org/10.11203/jar.29.s55
  DOI ID：10.11203/jar.29.s55, ISSN：0912-2834, CiNii Articles ID：130003393438, CiNii Books ID：AN10041511
• Investigation of condensation reaction during phenol liquefaction of waste woody materials
  Q. Wang; N. Mitsumura; Q. Chen; A. Sarkar; H. Kurokawa; K. Sekiguchi; K. Sugiyama
  International Journal of Sustainable Development and Planning, Volume：9, First page：658, Last page：668, Jan. 2014
  The liquefaction of waste woody materials in the presence of phenol and acid catalyst is a promising method for converting waste woody materials into phenolic resin. The condensation reaction during the liquefaction process is a major problem for its practical application. The effects of various reaction conditions on the extent of the condensation reaction were investigated. The residue content, molecular weight distributions and phenol concentration were measured to investigate the condensation reaction. As a result, it was observed that the intense reaction conditions caused fast liquefaction and led to a remarkable condensation reaction. It was also found that the residue content began to increase at an earlier reaction time when a more remarkable condensation reaction occurred. These results indicated that the condensation reaction was one of the causes for too much degradation of liquefied wood molecules under intense liquefaction. The phenol concentrations in the liquefaction products were measured to investigate their effect on the condensation reaction. It was shown that the phenol concentration was 8% lower at the end of the reaction when the condensation reaction was high. It was indicated that the drop in phenol concentration suppressed the liquefaction and promoted the condensation reaction. The addition of methanol during the liquefaction process suppressed the condensation reaction. The residue content was 11% when 50% methanol was added, while it reached 66% when methanol was not added. This can be because methanol reduced the bound phenol, which could be a reaction site of condensation reaction.
  DOI：https://doi.org/10.2495/SDP-V9-N5-658-668
  DOI ID：10.2495/SDP-V9-N5-658-668, ISSN：1743-7601, SCOPUS ID：84939484204
• Oil aggregated behavior for coal recovery and combustion characteristics of their aggregates from different grade coals
  Q. Wang; H. Niida; C. Liu; H. Kurokawa; A. Sarkar; K. Sekiguchi; K. Sugiyama
  International Journal of Sustainable Development and Planning, Volume：9, First page：692, Last page：704, Jan. 2014
  Large amounts of waste fine coals are very difficult to be treated due to the presence of ash and inorganic sulphur compounds. In order to use waste fine coal efficiently, a retrieval technique is necessary for the recovery of combustible contents of coal from fine waste coals. Nowadays, a flotation process has been used for the treatment, but it is impractical for developing countries due to its higher costs. Therefore, oil agglomeration process has been used to deal with these problems. In this study, the factors affecting the coal cleaning efficiency of the oil agglomeration process were investigated with the element contents and chemical structure of three different grade coals. Chemical contents in three different grade coals were determined by proximate and ultimate analyses and the differences in chemical structure of carbonaceous contents of different grade coals were investigated by a Fourier transform-infrared spectrometry. In free coals or their mixed samples, the ratio of ash and carbonaceous contents were maintained to make it homogeneous. From the results of oil agglomeration experiments, it was concluded that the characteristics of agglomerate and the coal cleaning efficiency of oil agglomeration were not only influenced by the type of oils but also by the oxygen contents and the aromatic and aliphatic chemical structures in different grade coals. The oxygenic functional groups of carbonaceous contents in coal samples prevented oil from attaching the carbonaceous surface and form the bulky aggregate. This depressed the combustible matter recovery, but this was resolved by changing the oil types. Oxygen contents in oils such as vegetable oil played a role in bridging material to the oxygenic functional groups of carbonaceous contents in coal samples. Meanwhile, it was observed that aromatic functional groups in carbonaceous contents interacted badly with the aliphatic functional groups in oil due to the resonance inspection of delocalized π electrons. Comparatively carbonaceous contents consisting of more aliphatic series or graphite-reinforced structures were tended to form aggregates easily. Even when different types of coals were used in the oil agglomeration, it was possible to achieve a better efficiency by taking these factors into account. Moreover, by thermogravimetric-derivative thermogravimetric (TG-DTG) analyses, it was found that the combustion characteristics of carbonaceous contents were improved due to oil attachment.
  DOI：https://doi.org/10.2495/SDP-V9-N5-692-704
  DOI ID：10.2495/SDP-V9-N5-692-704, ISSN：1743-7601, SCOPUS ID：84939476228
• Chemical characterization of carbonaceous PM10 in Bangkok, Thailand
  Siwatt Pongpiachan; Shinji Kudo; Kazuhiko Sekiguchi
  Asian Journal of Applied Sciences, Volume：7, Number：5, First page：325, Last page：342, 2014
  Four Organic Carbon (OC) compositions and three Elemental Carbon (EC) fractions in PM10 collected monthly from February to December 2007 at eight PCD air quality observatory sites were analysed by using a DRI Model 2001. Since both OC and EC play a major role in governing the gas-particle partitioning of carcinogenic Polycyclic Aromatic Hydrocarbons (PAHs), it is therefore, important to investigate the spatial and temporal distributions of carbonaceous fractions in Bangkok. The sum of OC (ΣOC) and EC (ΣEC) collected at eight PCD sites were 71.4±19.3 μg m-3 and 74.9±32.7 μg m-3, correspondingly. The relatively low OC/EC ratios observed in Bangkok highlight the influence of transportation sector in governing carbonaceous aerosols, particularly in heavy traffic congestion area. Three-dimensional plots of Principal Components (PCs) successfully discriminate "traffic emission" group from those of "urban residential background" group. In addition, the estimated Incremental Lifetime Particulate Exposure (ILPE) of carbonaceous compositions were constantly highest at heavy traffic congestion area in both genders with the average values of 1,130±457 and 622±252 mg for TC accumulated in male and female, respectively. © 2014 Knowledgia Review, Malaysia.
  knowledgia review, English, Scientific journal
  DOI：https://doi.org/10.3923/ajaps.2014.325.342
  DOI ID：10.3923/ajaps.2014.325.342, ISSN：1996-3343, SCOPUS ID：84903844988
• Release behaviour of cryptomeria japonica pollen allergenic cry j 1 and cry j 2 in rainwater containing air pollutants
  Q. Wang; S. Nakamura; S. Gong; M. Suzuki; D. Nakajima; Y. Takai; S. Lu; K. Sekiguchi; M. Miwa
  International Journal of Sustainable Development and Planning, Volume：9, First page：42, Last page：53, Jan. 2014
  Japanese cedar (Cryptomeria japonica) pollinosis is the most popular pollinosis in Japan. In recent years, it was reported that the most Cryptomeria japonica pollen allergenic species were scattered as fi ne particles in the urban atmosphere. It is thought that allergenic fi ne particles are responsible for inducing asthma by breaking into lower respiratory tract; this phenomenon was observed in fi eld investigations during sunny days after rainfall. Hence, it is considered that the release of fi ne allergenic species derived from pollen grains may be induced during rainfall events. For this reason, we investigated the releasing behaviour of Cryptomeria japonica pollen allergenic species in rainwater containing air pollutants, through rainwater sampling and laboratory experiments. The pollen grain counts, pollen burst ratios, ionic concentrations and pH in each rainwater sample were measured, when rainwater samples were separately collected in Saitama City, a suburban area north of Tokyo metropolis. Additionally, three simulated rainwater (SR) samples were prepared to investigate the releasing behaviour of pollen allergenic species. In the samplings, the most pollen grains were trapped into initial rainwater (IR). Moreover, burst pollen grains were observed in many rainwater samples. Burst ratio of pollen grains were positively correlated with pH and ionic concentrations in rainwater. Therefore, it was thought that pollen grains were washed out by IR containing air pollutants. On the other hand, for the laboratory experiments, the elution of allergenic Cry j 1 and Cry j 2 was observed when pollen grains were exposed to different SR samples. A time-dependent increase of Cry j 1 was observed, but the elution of Cry j 2 was not observed from pollen grains exposed to SR samples. In particular, the elution of Cry j 1 increased by contact with SR samples under conditions of Asian dust events. The results demonstrated that the burst of pollen grains is associated with the production of fi ne particles containing pollen allergenic species, and that the release of allergenic species was induced by rainwater containing air pollutants.©2014 WIT Press.
  DOI：https://doi.org/10.2495/SDP-V9-N1-42-53
  DOI ID：10.2495/SDP-V9-N1-42-53, ISSN：1743-7601, SCOPUS ID：84901200693
• Measurements of changes in the atmospheric partitioning of bifunctional carbonyls near a road in a suburban area　　　　　　　　　　　　　　　
  R. Ortiz; S. Shimada; K. Sekiguchi; Q. Wang; K. Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：81, First page：554, Last page：560, Dec. 2013
  Bifunctional carbonyls are ubiquitous in the atmosphere and are important contributors to atmospheric aerosols through heterogenous reactions. However, the actual contributions of bifunctional carbonyls to atmospheric aerosols have been little measured because of their capacity to coexist in both the gaseous phase and the particulate phase, making it difficult to sample them in both phases simultaneously. Using a short time resolution (2 h), we measured the atmospheric partitioning of semivolatile species to understand their contributions to atmospheric aerosols. Our results indicate that equilibrium between the gaseous phase and the particulate phase was due not only to thermodynamic partitioning but also to an aging process. Fresh emissions from motor vehicles affected the partitioning, and partitioning coefficients stabilized when the aerosols aged. The contribution of bifunctional carbonyl compounds to atmospheric aerosols was 3-8 orders of magnitude higher than that estimated by thermodynamic predictions, corroborating previous findings. (C) 2013 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2013.09.045
  DOI ID：10.1016/j.atmosenv.2013.09.045, ISSN：1352-2310, eISSN：1873-2844, SCOPUS ID：84885415652, Web of Science ID：WOS:000329377600059
• Carbonaceous and ionic components in ultrafine and fine particles at four sampling sites in the vicinity of roadway intersection　　　　　　　　　　　　　　　
  Kyung Hwan Kim; Kazuhiko Sekiguchi; Shinji Kudo; Masatoshi Kinoshita; Kazuhiko Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：74, First page：83, Last page：92, Aug. 2013, [Reviewed]
  Ultrafine particles (UFPs; Dp < 0.1 mu m) and fine particles (FPs; Dp < 2.5 mu m) were simultaneously collected for 11 h periods in the daytime and in the nighttime at four sites (S1-S4) around a roadway intersection in an urban area. Sampling was carried out for 14 consecutive days to determine the effect of the intersection on the chemical composition of atmospheric UFPs and FPs. The relative contributions of organic carbon (OC) and elemental carbon (EC) to total carbon (TC) in the daytime samples were 65-86% (UFPs: 83-86%; FPs: 65-75%) and 14-35% (UFPs: 14-17%; FPs: 25-35%), respectively, whereas those in the nighttime samples accounted for 71-90% (UFPs: 87-90%; FPs: 71-78%) and 10-29% (UFPs: 10-13%, FPs: 22-29%), respectively, indicating that the contribution of EC in both UFPs and FPs was higher during the daytime. The decrease in the concentration of carbonaceous components with distance from the intersection indicated a strong effect of motor vehicles emissions on the composition of UFPs and FPs around the intersection. The diurnal variations of sulfate and nitrate in UFPs are consistent with the seasonal variations of sulfate and nitrate in FPs showing higher sulfate and nitrate concentrations in summer and winter, respectively. Not observed in FPs, the diurnal patterns of sulfate and nitrate in UFPs may be closely related to particle size in comparison with larger particles, because smaller particles are more strongly affected by the surrounding environment, for example, through oxidation and dissociation. The present study provides interesting observation that the emission characteristics of OC and EC fractions can be different in the same roadside environment depending on the distance from roadway intersection and particle sizes. Furthermore, concentration difference between EC and black carbon (BC) was found at specific site indicating different EC emission characteristics at the same roadside environment. (C) 2013 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2013.03.016
  DOI ID：10.1016/j.atmosenv.2013.03.016, ISSN：1352-2310, Web of Science ID：WOS:000320969500010
• Removal of ethylene and secondary organic aerosols using UV-C254 + 185 nm with TiO2 catalyst　　　　　　　　　　　　　　　
  Ken-Lin Chang; Kazuhiko Sekiguchi; Qingyue Wang; Feng Zhao
  Aerosol and Air Quality Research, Volume：13, Number：2, First page：618, Last page：626, 2013, [Reviewed]
  In this investigation we evaluated the feasibility and effectiveness of ozone-producing UV (254 + 185 nm) irradiation and a TiO2photocatalyst for degradation of ethylene, which is strongly hydrophobic and does not decompose easily in a humid environment. Tests were performed in a photoreactor (V = 0.55 L) under UV irradiation at various wavelengths (365, 254 and 254 + 185 nm), relative humidities (RH <
  1% and RH >
  86%), atmospheres (pure N2and air), residence times (11- 33 sec), initial ethylene concentrations in the range of 25-105 ppmv and TiO2contact areas (86.4-259 cm2) with presumably ambient pressure and temperature. The experimental results demonstrated that the use of TiO2under 254 + 185 nm UV irradiation significantly enhanced the photodegradation of ethylene compared to the case of UV irradiation alone, due to the synergistic effect of photochemical oxidation in the gas phase and photocatalytic oxidation on the TiO2surface. Photodegradation induced with 254 + 185 nm UV irradiation was compared with photodegradation induced with UV irradiation at wavelengths of 365 and 254 nm. The highest conversion and mineralization levels were obtained with 254 + 185 nm UV irradiation among the three tested UV sources. Moreover, irradiating with 254 +185 nm light generated secondary organic aerosols (SOA) via gas-to-particle conversion of organic compounds in the air stream. The results indicate that the concentration of generated SOAs decreased in the presence of the TiO2catalyst, and thus that TiO2may be used to effectively control the emissions of undesirable SOAs. In an application test, for photocatalytic oxidation with 254 + 185 nm UV irradiation, corresponding to a flow rate of 0.5 L/min, and an initial concentration of 34 ppmv, over 90% of the inlet ethylene could be degraded. Copyright © Taiwan Association for Aerosol Research.
  English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2012.07.0195
  DOI ID：10.4209/aaqr.2012.07.0195, ISSN：1680-8584, SCOPUS ID：84874371255, Web of Science ID：WOS:000315327400018
• Size-segregated allergenic particles released from airborne Cryptomeria japonica pollen grains during the Yellow Sand events within the pollen scattering seasons
  Qingyue Wang; Xiumin Gong; Miho Suzuki; Senlin Lu; Kazuhiko Sekiguchi; Daisuke Nakajima; Makoto Miwa
  Asian Journal of Atmospheric Environment, Volume：7, Number：4, First page：191, Last page：198, 2013
  Cryptomeria japonica pollen is the most common pollen, which are scattering during each spring season in Japan. Japanese cedar (Cryptomeria japonica) pollinosis is one of seasonal allergic rhinitis that mainly occurs in Japan. In addition, long range transportation of Yellow Sand from the East Asian continent was also found during the pollen scattering seasons in Japan. Therefore, the interaction or impact between pollen and Yellow Sand should be concerned. In this study, our objective was to investigate the airborne behaviour of Cryptomeria japonica pollen grains and its size-segregated allergenic (Cry j 1) particles as the airborne tracer of Cryptomeria japonica pollen during the Yellow Sand events. Airborne Cryptomeria japonica pollen grains and its size-segregated allergenic particles were collected at roadside of urban residential zones of Saitama city during the pollination periods from February to March in two year investigation of 2009 and 2010. The overlap of Yellow Sand events and dispersal peak of pollen grains was observed. According to the Meteorological data, we found that the peaks of airborne pollen grains appeared under higher wind speed and temperature than the previous day. It was thought that Yellow Sand events and airborne pollen counts were related to wind speed. From the investigation of the airborne behavior of the size-segregated allergen particles by determining Cry j 1 with Surface Plasmon Resonance (SPR), the higher concentrations of the allergenic Cry j 1 were detected in particle size equal to or less than 1.1 μ(PM1.1) than other particle sizes during Yellow Sand events, especially in the rainy day. We conclude that rainwater trapping Yellow Sand is one of the important factors that affect the release of allergenic pollen species of Cry j 1. Therefore, it is very important to clarify the relationships between Cryptomeria japonica pollen allergenic species and chemical contents of the Yellow Sand particles in further studies.
  Korean Society for Atmospheric Environment, English, Scientific journal
  DOI：https://doi.org/10.5572/ajae.2013.7.4.191
  DOI ID：10.5572/ajae.2013.7.4.191, ISSN：2287-1160, SCOPUS ID：84893421746
• Study on heterogeneous reaction between tar and ash from waste biomass pyrolysis and gasification
  Q. Wang; T. Endo; P. Apar; L. Gui; Q. Chen; N. Mitsumura; Q. Qian; H. Niida; S. Animesh; K. Sekiguchi
  WIT Transactions on Ecology and the Environment, Volume：176, First page：291, Last page：302, Jan. 2013
  Fossil energy resources that are available in the world are exhaustible. Therefore, the renewable biomass resource has attracted a lot of attention as the future energy resource. In addition, it is an advantage that the biomass grows while absorbing CO2, contributing to the prevention of global warming. Biomass utilization technologies are classified as pyrolysis and gasification, fermentation, and combustion. Fuel gases and synthesis gases produced by the pyrolysis and gasification is used as power generation, heating, chemical products, etc. However, pyrolysis and gasification processes also generated condensable organic compounds, so-called "tar". Most tar contents are present as the gases at high temperature. However, when the temperature is cooled down lower than their boiling point, causing a black oily liquid lead to the equipment failure, the appropriate processing is required. As the processing method, using the catalytic tar decomposition has been widely studied. In the present study, we have carried out the thermal decomposition of cellulose, in the experimental apparatus modeling a fluidized bed gasifier. The thermal decomposition of cellulose, tar and gas is generated, tar is collected and cooled, and the gases were measured by a gas-chromatograph with a flame ionization detector (GC-FID) and with a thermal conductivity detector (GCTCD). Then, K and Ca are selected as the catalysts of alkali metals and alkaline earth metals contained in the waste biomass. They are present in the state of oxide or carbonate during pyrolysis and gasification. We conducted a similar experiment. The amount of condensable products and heavy tar were decreased by installing K2CO3 and Ca(OH)2. Additionally, they brought further gas production. It can be concluded that alkali metal compound (K2CO3) and alkaline earth compound (CaO) have a catalytic effect to decompose tar contents, to enhance gaseous production. © 2013 WIT Press.
  DOI：https://doi.org/10.2495/ESUS130251
  DOI ID：10.2495/ESUS130251, ISSN：1743-3541, SCOPUS ID：84887605199
• Suppression method of the condensation reaction during phenol liquefaction of woody material
  Q. Wang; N. Mitsumura; Q. Chen; P. Apar; H. Niida; S. Ito; T. Endo; S. Animesh; H. Kurokawa; K. Sekiguchi; K. Sugiyama
  WIT Transactions on Ecology and the Environment, Volume：176, First page：279, Last page：290, Jan. 2013
  The liquefaction of woody materials in the presence of phenol and acid catalyst is a promising method to utilize the waste woody materials into phenolic resin. However, the condensation reaction is a major problem for its practical applications. In order to suppress condensation reactions, methanol was added to the liquefaction medium. Even the intense condensation reactions were suppressed by the addition of 50% methanol (mol% to phenol). The effect of methanol was further confirmed by the measurement of molecular weight distribution. In the case of mild condensation, addition of 5% methanol suppressed the production of the residues. At the same time, the liquefaction rates overall were faster than the case without methanol. It was inferred that the existence of methanol lowered the amount of combined phenol which could be the reaction site of the condensation reaction. On the other hand, larger amounts of methanol (100%) retarded the liquefaction rate and the consumption rate of phenol. The actual reaction temperature in the reactor was lower than the setup temperature of the oil bath when the methanol was added. The investigation of the IR spectra showed that there were almost no differences between the functional groups of the liquefied products obtained with and without methanol. The addition of small amounts of methanol could be applicable because the disadvantages of methanol addition could be reduced. © 2013 WIT Press.
  DOI：https://doi.org/10.2495/ESUS130241
  DOI ID：10.2495/ESUS130241, ISSN：1743-3541, SCOPUS ID：84887604741
• Clarification of the reaction at the solution interface of pyrite during oil agglomeration for developing desulfurization and coal cleaning efficiency
  Q. Wang; H. Niida; P. Apar; Q. Chen; L. Gui; Q. Qian; N. Mitsumura; T. Endou; S. Animesh; H. Kurokawa; K. Sekiguchi; K. Sugiyama
  WIT Transactions on Ecology and the Environment, Volume：176, First page：303, Last page：313, Jan. 2013
  Recently, large amounts of waste fine coals have been produced which are difficult to treat because of the high ash content and inorganic sulfuric compounds. In order to make efficient use of waste fine coal, the retrieval technique is necessary for recovery of coal combustible content from fine waste coals. Nowadays a floatation process is able to operate, but it is impractical for developing countries due to high costs. An oil agglomeration process can deal with these problems. In this study, we investigate the mechanism of the solution interface reaction on oil agglomeration in order to separate pyrite sulfur effectively from waste fine coal. For this purpose, we adjusted the pH of the solution of oil agglomeration experiments to the basic condition, which changed the surface characteristics to hydrophilicity from hydrophobicity. Furthermore, pH and dissolved oxygen changes of the solution were continually monitored and free ferric ions of the waste liquid were measured by flame atomic absorption spectrometry. These factors have a relationship with the oxidation and surface reaction of pyrite sulfur in the solution. Under high basic conditions, pyrite sulfur reduction indicated high values since the pyrite surface became hydrophilic due to covering of the surface of the pyrite sulfur by ferric hydroxide. As a result, the pyrite content did not recover together with hydrophobic carbonaceous content especially under high basic conditions. However, coal cleaning efficiency, especially of combustible matter recovery, dropped under these conditions due to increased ion intensity. © 2013 WIT Press.
  DOI：https://doi.org/10.2495/ESUS130261
  DOI ID：10.2495/ESUS130261, ISSN：1743-3541, SCOPUS ID：84887590773
• Behavior of suspended particulate matter emitted from combustion of agricultural residue biomass under different temperatures
  Q. Wang; S. Itoh; K. Itoh; P. Apaer; Q. Chen; D. Niida; N. Mitsumura; S. Animesh; K. Sekiguchi; T. Endo
  WIT Transactions on Ecology and the Environment, Volume：176, First page：315, Last page：325, Jan. 2013
  There are large quantities of waste rice husk and straw estimated around 3.9 million tons as biomass waste every year in Japan. Air pollutants emitted from exhaust gases of rice husk incineration lead to environmental damage, not only because of the influence on global environment and climate, when released into the atmosphere, but also on human health due to local air pollution. Therefore, it is necessary to effectively utilize waste rice husk and straw to reduce air pollutants. In recent years, there has been an increasing demand on the utilization of unused biomass instead of fossil oil fuel in combustors for farming-greenhouses heating during the winter season. The increasing demand will increase the running costs. In general, since these combustors are small in size, there is a lack of regulations or laws (e.g. The Air Pollution Control Act and The Waste Disposal and Public Cleaning Law) in operation for their air pollution control. So far, small size combustors are characterized by their simplicity of structure and low costs. However, they emit visible black carbon (elemental carbon) due to their poor combustion performance. In this study, we investigated that the possibility of the substitution of fossil fuel by waste rice husk and rice straw in laboratory model combustion experiments. We evaluated the emission behavior of harmful air pollutants emitted from rice husk and straw combustion by measuring carbonaceous and ionic composition of suspended particulate matter in the exhaust gases. From the analytical results we found that particulate mass concentrations reduced substantially at high temperature combustion. From the results of our study, it can be suggested that stable combustion performance under suitable conditions in order to control less air pollutants emitted from biomass fuel although small size combustors are still not regulated. © 2013 WIT Press.
  DOI：https://doi.org/10.2495/ESUS130271
  DOI ID：10.2495/ESUS130271, ISSN：1743-3541, SCOPUS ID：84887583765
• Process analysis of waste bamboo materials using solvent liquefaction
  Q. Wang; Q. Qiao; Q. Chen; N. Mitsumura; H. Kurokawa; K. Sekiguchi; K. Sugiyama
  WIT Transactions on Ecology and the Environment, Volume：176, First page：267, Last page：277, Jan. 2013
  Bamboo is one of the most significant biomass resources which has been used in houses, flooring, construction of scaffolding and bridges, etc. The solvent liquefaction process is one promising technique for effective utilization of waste bamboo materials for the lignocelluloses which can be converted to liquid reactive materials as biomass-based materials. Bamboo has the advantage of providing liquefied products with a small range of variances. The components of bamboo have high acidity in the presence of mineral acid catalysts and possess constituents which can react with polyethylene glycol 400 (PEG 400). In this study, waste bamboo materials have been used in liquefaction experiments. The liquefaction process and liquefied residue have been measured according to the liquefied conditions and the surface changes of waste bamboo samples observed by a scanning electron microscope. The changes in the functional groups have been analysed by a Fourier transform infrared spectrometer and the behavior of the crystalline structures of liquefied bamboo has been determined by X-ray diffraction. Other experiments, such as the degree of polymerization, have also been carried out to confirm the results. It was found that increments of the temperature and the amount of the acid catalysts improved the efficiency of liquefaction. Meanwhile, the dissolution time of lignin was significantly shorter than that of cellulose in the solvent liquefaction process of PEG 400. © 2013 WIT Press.
  DOI：https://doi.org/10.2495/ESUS130231
  DOI ID：10.2495/ESUS130231, ISSN：1743-3541, SCOPUS ID：84887571207
• Diurnal and nocturnal behaviour of airborne Cryptomeria japonica pollen grains and the allergenic species in urban atmosphere of saitama, Japan
  Qingyue Wang; Shinichi Nakamura; Senlin Lu; Daisuke Nakajima; Miho Suzuki; Kazuhiko Sekiguchi; Makoto Miwa
  Asian Journal of Atmospheric Environment, Volume：7, Number：2, First page：65, Last page：71, 2013
  Japanese cedar (Cryptomeria japonica) pollinosis is the most popular pollinosis in Japan. It has been reported that Cryptomeria japonica pollen allergenic species are suspended as fine particles in the urban atmosphere. These allergenic fine particles are responsible for inducing asthma by breaking into the lower respiratory tract. It has also been found that pollinosis symptoms on the sufferers appear mainly at night-time by the results from epidemiological studies. However, the exact reason for these phenomena is not yet clarified. In this study, the diurnal and nocturnal behaviours of Cryptomeria japonica pollen grains and their allergenic species in the urban area of Saitama city of Kanto Plain were investigated. Airborne pollen grains and allergenic Cry j 1 concentrations in total suspended particulate matter (TSP) were investigated at two sampling sites, a heavy traffic road (roadside site) and at the balcony of the 10th floor of the Building of Research and Project of Saitama University (general urban site). The latter sampling site where located about 300 m away from the roadside site was used as a general urban site unaffected by automobile traffic. The airborne pollen counts were measured with a real-time pollen monitor. Cry j 1 particles were collected with two high volume air samplers, and these concentrations were measured by surface plasmon resonance method with a Biacore J system. The diurnal variation of the airborne pollen counts was similar to the trends of temperature and wind speed during the day-time
  whereas its tendency with wind speed trend was not observed during the night-time. Airborne pollen counts were lower with northern wind than with southern wind because the pollen comes from the mountainous areas, and the mountains in the south are closer, about half the distance to the northern mountains. It is suggested that the peaks of airborne pollen counts during night-time in the sampling site occurred by transport of pollen grains released during day-time in the mountainous forest areas, located c.a. 100 km away from the sampling site. On the roadside site the allergenic Cry j 1 concentrations were higher than at the general urban site, nevertheless pollen grains counts were lower. These results suggested that worsening of pollinosis symptoms during nighttime in urban area was caused by transport of pollen grains during day-time in the mountainous forest areas. Moreover, pollen allergenic species become different morphology from pollen grain at roadside site, and the subsequent pollen grains re-suspension by automobile traffic.
  Korean Society for Atmospheric Environment, English, Scientific journal
  DOI：https://doi.org/10.5572/ajae.2013.7.2.065
  DOI ID：10.5572/ajae.2013.7.2.065, ISSN：2287-1160, SCOPUS ID：84883251208
• Atmospheric Concentrations of Semivolatile Bifunctional Carbonyl Compounds and the Contribution from Motor Vehicles
  Ricardo Ortiz; Satoru Shimada; Kazuhiko Sekiguchi; Qinyue Wang; Kazuhiko Sakamoto
  Asian Journal of Atmospheric Environment, Volume：7, Number：3, First page：152, Last page：160, 2013
  Seven potentially harmful bifunctional carbonyls were measured in particulate and gaseous phases at a roadside site and a suburban site in an area about 30 km north-northwest from Tokyo metropolitan area in the Kanto region in Japan. For the first time, these compounds were measured in both phases with a time resolution of 2 h. We found that wind direction is an important parameter that affects the collection of these compounds near the source, and it can cover the effects of other important variables. Our results confirmed that motor vehicles and especially diesel fuelled vehicles are important sources of these compounds. Photochemical generation is also an important source of these compounds in the gaseous phase. Transportation from the urban area is also important, particularly in the aerosol phase.
  Korean Society for Atmospheric Environment, English, Scientific journal
  DOI：https://doi.org/10.5572/ajae.2013.7.3.152
  DOI ID：10.5572/ajae.2013.7.3.152, ISSN：2287-1160, SCOPUS ID：84886467846
• Differences of chemical species and their ratios between fine and ultrafine particles in the roadside environment　　　　　　　　　　　　　　　
  Shinji Kudo; Kazuhiko Sekiguchi; Kyung Hwan Kim; Masatoshi Kinoshita; Detlev Moeller; Qingyue Wang; Hiroshi Yoshikado; Kazuhiko Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：62, First page：172, Last page：179, Dec. 2012, [Reviewed]
  Chemical components of fine particles (FPs; aerodynamic diameter, Dp <2.5 mu m) and ultrafine particles (UFPs; Dp < 0.1 mu m) at Japanese and German roadsides were investigated during summer. The UFPs/FPs ratio for organic carbon (CC) concentrations on weekdays was 34.5% and 25.0% at Japanese and German roadsides, respectively, whereas 33% and 6.4% for elemental carbon (EC) concentrations, respectively. These results thus indicate a higher OC and a lower EC contribution from UFPs at the Japanese roadside than at the German roadside. In particle samples, OC2 and OC3 constituted a high proportion of UFPs, and pyrolyzed OC and EC1 were predominant among FPs of 0.1 mu m < Dp <2.5 mu m. Our results showed roadside environment exist not only primary FPs and UFPs but also secondary FPs and UFPs from photochemical reactions or long-range transport. (C) 2012 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2012.08.039
  DOI ID：10.1016/j.atmosenv.2012.08.039, ISSN：1352-2310, eISSN：1873-2844, Web of Science ID：WOS:000311188200017
• Studies on the atmospheric ultrafine particles and the air purification techniques for VOC gases　　　　　　　　　　　　　　　
  SEKIGUCHI Kazuhiko
  Journal of Japan Society of Air Pollution, Volume：47, Number：4, First page：137, Last page：144, Jul. 2012
  In relation to atmospheric environment, I have studied two different research fields "Field sampling of atmospheric aerosols" and "Air purification techniques for organic gases." In this paper, the outline of these researches are introduced based on field sampling of atmospheric ultrafine particles near the emission sources using a new developed inertial filter (INF) sampler, and investigation of effective treatment for VOC gases and their decomposition products using combined advanced oxidation process (AOP) techniques.
  Japan Society for Atmospheric Environment, Japanese
  DOI：https://doi.org/10.11298/taiki.47.137
  DOI ID：10.11298/taiki.47.137, ISSN：1341-4178, CiNii Articles ID：10030508092, CiNii Books ID：AN10512108
• Gas/particle partitioning of low-molecular-weight dicarboxylic acids at a suburban site in Saitama, Japan　　　　　　　　　　　　　　　
  Linfa Bao; Mariko Matsumoto; Tsutomu Kubota; Kazuhiko Sekiguchi; Qingyue Wang; Kazuhiko Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：47, First page：546, Last page：553, Feb. 2012, [Reviewed]
  Low-molecular-weight dicarboxylic acids (diacids) exhibit semivolatile behavior in the atmosphere, but their partitioning between the gaseous and particulate phases is still unclear. An annular denuder-filter pack system with a cyclone PM2.5 was employed to investigate the gaseous and particulate phase concentrations of diacids, with high collection efficiency of most target compounds. Saturated diacids, unsaturated diacids, ketocarboxylic acids, and dicarbonyls were determined in gaseous and particulate samples collected from a suburban site in Japan, during 2007 summer, 2008 late-winter and early-winter. The concentrations of gaseous and particulate diacids in early-winter were lower than those in summer, but higher than those in late-winter. Individual diacid in gaseous phase showed a relatively good correlation with ambient oxidants, but a low correlation with NO gas (a primary pollutant). Particulate fraction to the total amount (F-p) of individual acid was larger in winter than in summer, and also was larger at night than in the daytime. In the same sample, individual diacid and ketocarboxylic acid had higher particulate phase occurrence (F-p > 56% in summer), whereas unsaturated diacid had higher gaseous phase occurrence (F-p < 18% in summer). In summer, gas/particle partitioning of diacids varied diurnally; F-p values of oxalic and glyoxylic acids increased from their lowest values in the morning to their highest values at night, exhibiting the similar diurnal variation of relative humidity in the atmosphere. The higher humidity at night may lead to the formation of droplets in which water-soluble gaseous phases can dissolve, thus promoting gas-to-particle conversion. These results suggest that gas/particle partitioning of diacids depends not only on the concentrations in the gaseous phase by photochemical oxidation, but also on the characteristics of the atmosphere (e.g., temperature, sunlight, and relative humidity) and the aerosols (e.g., acidity, alkaline composition, and water content). (C) 2009 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2009.09.014
  DOI ID：10.1016/j.atmosenv.2009.09.014, ISSN：1352-2310, eISSN：1873-2844, Web of Science ID：WOS:000301157700061
• Characterization of the physical form of allergenic Cry j 1 in the urban atmosphere and determination of Cry j 1 denaturation by air pollutants
  Qingyue Wang; Jun Morita; Xiumin Gong; Shinichi Nakamura; Miho Suzuki; Senlin Lu; Kazuhiko Sekiguchi; Takuya Nakajima; Daisuke Nakajima; Makoto Miwa
  Asian Journal of Atmospheric Environment, Volume：6, Number：1, First page：33, Last page：40, 2012
  In this study, we characterized the physical form of allergenic Cry j 1 in the urban atmosphere. Through an immunofluorescence antibody method, we showed that allergenic Cry j 1 exists as fine particles (≤1.1 μm). To determine Cry j 1 concentrations and its particle size distribution, we used the ELISA method to confirm that most Cry j 1 exists as fine particles in the urban atmosphere and is found at high concentrations on fine day next to rainy day. Furthermore, we evaluated Cry j 1 denaturation by using the Biacore J system based on the surface plasmon resonence (SPR) principle and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We showed that the dissociation constant (KD) of Cry j 1 that has been exposed to urban polluted air is lower (1.76 ×10-14 M) than that of Cry j 1 (1.32×10-9-3.37× 10-9 M) of original pollen grains that has not been exposed to air pollutants. Cry j 1 turns into low molecular weight proteins by reacting with various acidic solutions. In sum, we showed that allergenic Cry j 1 exists as fine particles that can deposit in the lower respiratory tract. This finding clarifies the relationship between Japanese cedar pollinosis and air pollutants.
  Korean Society for Atmospheric Environment, English, Scientific journal
  DOI：https://doi.org/10.5572/ajae.2012.6.1.033
  DOI ID：10.5572/ajae.2012.6.1.033, ISSN：2287-1160, SCOPUS ID：84870012348
• Effect of phenol concentrations on the condensation reaction during the liquefaction of waste woody materials with phenol
  Q. Wang; N. Mitsumura; Q. Chen; P. Apar; Q. Qian; L. Gui; H. Niida; H. Kurokawa; K. Sekiguchi; K. Sugiyama
  WIT Transactions on Ecology and the Environment, Volume：163, First page：355, Last page：366, Jan. 2012
  The wood liquefaction technique using phenol is the developing method to utilize the waste woody materials for phenolic resin. However, the condensation reaction is one of the problems for popularizing the wood liquefaction technique. The lowering of the phenol concentrations in the wood liquefaction process is thought to be the cause of the condensation reaction. To find the reason and examine our hypothesis, woody meals (sawdust) were liquefied under the different conditions using phenol in the presence of sulfuric acid as a catalyst. Under the intensive liquefaction conditions such as higher reaction temperatures and more catalyst contents and smaller particle sizes of woody meal, remarkable condensation reaction was observed. It was found that the phenol concentrations were approximately 8% lower at the end of the reaction and became stable when the condensation reaction took place. It was indicated that the lowering of the phenol concentration suppressed the liquefaction reaction and prompted the condensation reaction. However, it was considered that the wood liquefaction also almost stopped when the condensation reaction was hardly observed. According to all results, it is suggested that the cause of the condensation reaction is not only due to the lowering of the phenol concentrations but also due to the decomposing of liquefied woody constituents into low molecules under the intense liquefaction. © 201 WIT Press.
  DOI：https://doi.org/10.2495/WM120321
  DOI ID：10.2495/WM120321, ISSN：1743-3541, SCOPUS ID：84867918629
• Influential factors on the oil agglomeration process for coal recovery from different grade coals
  Q. Wang; H. Niida; P. Apar; Q. Chen; L. Gui; Q. Qian; N. Mitsumura; H. Kurokawa; K. Sekiguchi; K. Sugiyama
  WIT Transactions on Ecology and the Environment, Volume：163, First page：187, Last page：198, Jan. 2012
  Large amounts of waste fine coals are produced, which are difficult to be treated because of high ash content and inorganic sulfuric compounds. In order to make efficient use of waste fine coal, a retrieval technique is necessary for the recovery of coal combustible content from fine waste coals. Nowadays, the floatation process can be used, but it is impractical for developing countries due to high costs, then the oil agglomeration process can deal with these problems. In this study, we investigated the affecting factors of coal cleaning efficiency of oil agglomeration on the element content and chemical structure of three different grade coals because there are many grades of coals around the world. For determination of chemical content in three different grade coals, the help of proximate and ultimate analysis was used, and then for investigation of their chemical structure differences of carbonaceous content, a Fourier transforminfrared spectrometry (FT-IR) was applied. Furthermore, for the oil agglomeration experiments, kerosene and vegetable oil which differ in structure were used as aggregating agents. We used ash free coals or their mixed samples which were conditioned to the ratios of carbonaceous and ash content in order to make it the same contained amounts. From the results of the oil agglomeration experiments, it was concluded that the characteristics of agglomerate and the coal cleaning efficiency of oil agglomeration are not only influenced by the oil types, but also affected by the oxygenic content, aromatic and aliphatic chemical structures in different grade coals. Oxygenic function groups of carbonaceous content in coal samples prevent oil from attaching to the carbonaceous surface and forming the bulky aggregate. Then, it leads to depressing combustible matter recovery; however, this can be improved by changing oil types. Oxygenic content in oil such as vegetable oil plays the role of the bridging material to the oxygenic function groups of carbonaceous content in coal samples. Moreover, the aromatic functional groups in carbonaceous content have the resonance inspection of delocalized π electrons; it interacts badly to the aliphatic functional groups in oil. Comparatively carbonaceous content consisting of more aliphatic series tends to form aggregates easily. Whatever coals we use on the oil agglomeration, it is possible to achieve better efficiency by taking these factors into account. © 201 WIT Press.
  DOI：https://doi.org/10.2495/WM120181
  DOI ID：10.2495/WM120181, ISSN：1743-3541, SCOPUS ID：84867909042
• Release rate of daughter allergenic species from Cryptomeria japonica pollen grains trapped in air polluted wet deposition
  S. Nakamura; Q. Wang; S. Gong; Y. Takai; S. Lu; D. Nakajima; M. Suzuki; K. Sekiguchi; M. Miwa
  WIT Transactions on Ecology and the Environment, Volume：157, First page：387, Last page：398, Jan. 2012
  High airborne concentrations of fine allergenic particles of Cryptomeria japonica pollen were determined during the pollen scattering spring seasons in Japan. In particular, this phenomenon was observed in field investigations during sunny days after rainfall. It is considered that the release of daughter allergenic species derived from pollen grains may be induced during urban rainfall events. Hence, it is necessary to do research in order to find the evidence of this phenomenon. There are two major daughter allergenic species produced by pollen in Japan, which are called Cry j 1 and Cry j 2 of Cryptomeria japonica pollen. Allergenic Cry j 1 mainly exists in the pollen wall surface (Ubisch body), while allergenic Cry j 2 is present as a starch granule in the pollen grain, it can be thought that the release mechanism of allergenic Cry j 1 and Cry j 2 species in rainfall should be different. Since the release mechanisms are still not clear, therefore, the aim of this study is to clarify the important mechanisms of elution rate of two kinds of daughter allergenic species when pollen grains are washed out by rainfall and exposed to polluted air. From the analytical results of rainwater samples and model laboratory experiments of simulated rainfall, it was indicated that a great number of pollen grains were trapped in initial rainfall. At the same time, many bursts of pollen grains were also observed in the rainwater. Thus, it is possible that the two daughter allergenic species will be released from the fractions of cell wall, burst pollen and the surfaces of pollen grains. Moreover, ionic concentrations in initial rainfall were higher than following wet deposition, because air pollutants were also abundantly trapped in the initial rainfall. Especially, it was found that the elution rate of allergenic Cry j 1 was increased when in contact with rainwater containing high ionic concentrations. In this case, elution of allergenic Cry j 1 was rapidly increased when in contact with a weak basic solution with high Ca2+ concentrations. Similarly, elution of allergenic Cry j 2 was also prompted from burst pollen washed out by rainfall and exposed to polluted air. Therefore, it is one important factor for the fast release of daughter allergenic species from pollen grains washed out by rainfall and exposed to polluted air including abundantly crustal particles such as road dust and Asian dust. © 2012 WIT Press.
  DOI：https://doi.org/10.2495/AIR120341
  DOI ID：10.2495/AIR120341, ISSN：1743-3541, SCOPUS ID：84865768733
• Characterization of suspended particulate matter emitted from waste rice husk as biomass fuel under different combustion conditions
  Q. Wang; T. Maezono; P. Apaer; Q. Chen; L. Gui; K. Itoh; H. Kurokawa; K. Sekiguchi; K. Sugiyama; H. Niida; S. Itoh
  WIT Transactions on Ecology and the Environment, Volume：157, First page：365, Last page：376, Jan. 2012
  There are large quantities of waste rice husk, e.g. around 3 million tons are estimated as biomass waste every year in Japan. Air pollutants emitted from exhaust gases of rice husk incineration lead to very important environmental damage, not only because of the influence on global environment and climate, when released into the atmosphere, but also on human health due to local air pollution. Therefore, it is necessary to effectively utilize waste rice husk and to reduce air pollutants. In recent years, there is an increasing demand on the utilization of unused biomass instead of fossil oil fuel in combustors for farminggreenhouses heating during the winter season. This increase in the demand will increase the running costs. In general, since these combustors are small in size, there is lack of regulations or laws (e.g. the air pollution control act and the waste disposal and public cleaning law) in operation for their air pollution control. So far, small size combustors are characterized by their simplicity of structure and the low costs; therefore, they emit visible black carbon (elemental carbon) due to their poor combustion performance. In this study, we investigated if fossil fuel can be substituted by waste rice husk in laboratory model combustion experiments. We evaluated the emission behavior of harmful air pollutants emitted from rice husk combustion by measuring carbonaceous and ionic composition of suspended particulate matter in the exhaust gases. From the analytical results we found that particulate mass concentrations can be reduced substantially at high temperature combustion. Fine particle size distribution is different with combustion conditions (e.g. smoldering combustion, flaming combustion). Ionic composition is mainly constituted by Na+, K+, Ca2+, Cl-, NO3- and SO42- which are easily vaporized, followed by homogeneous nucleation and heterogeneous condensation of these inorganic vapors. As the results of our study, it can be suggested that we have to ensure stable combustion performance under suitable conditions in order to control less air pollutants emitted from biomass fuel although small size combustors are still not regulated. © 2012 WIT Press.
  DOI：https://doi.org/10.2495/AIR120321
  DOI ID：10.2495/AIR120321, ISSN：1743-3541, SCOPUS ID：84865735286
• Spatial distributions of ultrafine particles and their behavior and chemical composition in relation to roadside sources　　　　　　　　　　　　　　　
  Shinji Kudo; Kazuhiko Sekiguchi; Kyung Hwan Kim; Kazuhiko Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：45, Number：35, First page：6403, Last page：6413, Nov. 2011, [Reviewed]
  Vertical and horizontal distributions of the chemical components of ultrafine particles (UFP: <0.1 mu m) in relation to roadside sources were investigated by using a newly developed PM(0.1) collection system with a UFP impactor filter (50% cut-off, 0.1 mu m: air flow rate, 40.0 L min(-1)). UFP were measured at a suburban roadside, at two background sites in Saitama (summer 2007 and winter 2008), and at two levels on a high-rise building in Tokyo (summer and winter 2005). The results from the high-rise building showed that ultrafine elemental carbon from vehicle exhaust can reach the upper atmosphere regardless of season because of the high diffusivity of UFP. The total concentrations of the carbonaceous and ionic components at all sites except the roadside site in summer were mostly within the same range. Therefore. UFP diffuse both vertically and horizontally, and its chemical components are distributed uniformly. The UFP composition in summer reflected not only the vehicle exhaust contribution but also photochemical formation, especially at the low-elevation sites, where the samplers were installed several meters above ground level. The results also showed that ionic components contributed to increases in the UFP levels. (C) 2011 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2011.08.021
  DOI ID：10.1016/j.atmosenv.2011.08.021, ISSN：1352-2310, Web of Science ID：WOS:000295653800015
• Daytime meteorological structures causing elevated photochemical oxidants concentrations in north Kanto, Japan　　　　　　　　　　　　　　　
  Shinri Hosoi; Hiroshi Yoshikado; Kazuhiko Sekiguchi; Qingyue Wang; Kazuhiko Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：45, Number：26, First page：4421, Last page：4428, Aug. 2011, [Reviewed]
  The north Kanto area is about 150 km north of the heavily populated and industrialized Tokyo metropolis, and local emissions of photochemical oxidants (Ox) precursors are limited because of little anthropogenic emission. Nevertheless, high Ox concentrations exceeding the warning level for Ox (>120 ppbv, 1-h average) are often observed there. We recently reported that high Ox concentrations in the north Kanto area occur under the coupled conditions of a southerly extended sea breeze transporting Ox from the southern urban area and a subsidence inversion layer restricting vertical dispersion. However, these meteorological conditions do not always lead to high Ox concentrations. To identify other conditions affecting the occurrence of high Ox concentrations in north Kanto, we examined meteorological conditions. Key meteorological structures were two thermal lows occurring on sunny days in districts neighboring the Kanto district on the west and north. When both thermal lows persisted in their morning positions until evening, a southerly sea breeze toward the thermal lows was maintained throughout the afternoon, transporting high levels of Ox formed in south Kanto, including Tokyo, to north Kanto. When a thermal low present only in the western district moved eastward to cover the central Kanto area during the afternoon, isobars in north Kanto acquired an east-west orientation and observed wind direction became consistently northerly, thus restricting transport of high Ox from south Kanto. (C) 2011 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2011.05.039
  DOI ID：10.1016/j.atmosenv.2011.05.039, ISSN：1352-2310, Web of Science ID：WOS:000293680100011
• Photocatalytic degradation of VOC gases considering reactor design for the treatment of decomposition intermediates using a short wavelength uv light and water droplets　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Kyung Hwan Kim
  Volatile Organic Compounds, First page：47, Last page：88, Apr. 2011
  Volatile organic compounds (VOCs) are of environmental concern because of their adverse effects on human health. Moreover, VOCs can adversely affect certain manufacturing processes
  for example, in semiconductor manufacturing, the wafer surface is damaged by VOCs. Although chemical filtration of classical removal techniques are effective in removing a variety of hazardous VOCs from air, these methods are expensive, and the materials used for adsorption and filtration have short and unpredictable life spans. Accordingly, there is much interest in developing new air purification systems for removing VOCs from air. In this Chapter, we introduce the photodegradation of toluene and benzene with TiO2 and UV254+185nm irradiation from an ozone-producing UV lamp as a first step to show VOC degradation in gas phase using short-wavelength UV irradiation with TiO2 catalyst with different UV sources. The results show that VOCs were decomposed and mineralized efficiently owing to the synergetic effect of photochemical oxidation in gas phase and photocatalytic oxidation on the TiO2 surface. The conversion levels obtained with UV254+185nm photoirradiated TiO2 were much higher than those obtained with conventional UV sources (UV365nm and UV254nm), which suffer from both catalyst deactivation and the generation of harmful intermediates. The products from the photo degradation of VOCs with the UV254+185nm photoirradiated TiO2 were mainly mineralized CO2 and CO, but some water-soluble organic intermediates were also formed under more severe reaction conditions. The water-soluble aldehydes and carboxylic intermediates disappeared from the effluent gas stream and were detected in the water impingers. These findings suggest that the intermediates can be washed out by conventional gas washing technique, such as wet scrubber or air washer. As a second step, we introduced removal of water-insoluble gaseous pollutants (NOx and toluene) with UV254+185nm irradiation in humid air to provide a useful process for effectively removing gaseous pollutants from the air and the treatment of intermediates by trapping the water-soluble intermediates into water droplets by the air washer. The results show that the OH radicals and ozone produced by UV254+185nm irradiation effectively degraded NOx and toluene to HNO3 and CO2, respectively. The organic intermediates formed during toluene degradation were highly water soluble and could therefore be effectively removed along with the HNO3, by the air washer. However, using the air washer as a means for effective removal of gaseous pollutants and their intermediates has disadvantages for example, 1) the reaction can be completed with 2-step process and 2) the size of air washer is relatively large. For these reasons, finally we studied and described VOCs degradation using an ultrasonic mist generated from TiO2 suspension under UV365nm, UV254nm, and UV254+185nm irradiations. With this technology, gaseous pollutants and the intermediates could be degraded and captured by water droplet and decomposed further in a liquid phase with 1-step process by generating mist droplets from ultrasonic atomization of TiO2 suspension. Organic gas species, UV wavelength, the diameter of ultrasonic mist containing photocatalyst particles (UMP), and the inhibition of the formation of secondary particles from intermediates were also investigated. In this method, VOCs were decomposed on the surface or inside of UMP and the degradation intermediates from hydrophobic gas could also be captured by water droplet and decomposed further in a liquid phase. © 2011 by Nova Science Publishers, Inc. All rights reserved.
  Nova Science Publishers, Inc., English, In book
  SCOPUS ID：84895363804
• Seasonal variation of carbonaceous and ionic components in ultrafine and fine particles in an urban area of Japan　　　　　　　　　　　　　　　
  Kyung Hwan Kim; Kazuhiko Sekiguchi; Masami Furuuchi; Kazuhiko Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：45, Number：8, First page：1581, Last page：1590, Mar. 2011, [Reviewed]
  The carbonaceous and ionic components of atmospheric ultrafine particles (UFPs; Dp < 0.1 mu m) and fine particles (FPs; Dp < 2.5 mu m) were measured four times during one year in Saitama City, Japan, in order to observe the seasonal variation of chemical components, to characterize the chemical components for the two particle sizes, and to estimate the possible emission sources qualitatively. Generally, the carbonaceous and ionic components in UFPs and FPs tended to increase from summer to winter. Over the year, approximately 63 similar to 67% of the total carbon (TC) consisted of organic carbon (OC) in FPs, whereas 80 similar to 88% of TC consisted of OC in UFPs. Char-elemental carbon (EC) and soot-EC constituted equal proportions of the total EC in UFPs, while soot-EC accounted for only a small amount of the total EC in FPs, indicating that char-EC and soot-EC were mainly present in relatively larger particles and much smaller particles, respectively. The water-soluble OC concentration tended to decrease from summer to winter, indicating that secondary organic aerosol formation dominated the OC fractions during the summer sampling period. The transport of atmospheric particulate matter from cities to the north of the sampling site is one reason for the high levels of carbonaceous components in FPs for the fall and winter samples. On the other hand, Tokyo and other industrial cities near the ocean are responsible for the highest soot-EC concentrations found in the summer FP samples. (C) 2010 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2010.12.037
  DOI ID：10.1016/j.atmosenv.2010.12.037, ISSN：1352-2310, eISSN：1873-2844, Web of Science ID：WOS:000288346100011
• Characteristics of Atmospheric Elemental Carbon (Char and Soot) in Ultrafine and Fine Particles in a Roadside Environment, Japan　　　　　　　　　　　　　　　
  Kyung Hwan Kim; Kazuhiko Sekiguchi; Shinji Kudo; Kazuhiko Sakamoto
  AEROSOL AND AIR QUALITY RESEARCH, Volume：11, Number：1, First page：1, Last page：12, Feb. 2011, [Reviewed]
  Atmospheric carbonaceous components, particularly char and soot in ultrafine particles (UFPs; Dp < 0.1 mu m) and fine particles (FPs; Dp < 2.5 mu m), were measured four times during one year in Saitama City, Japan, to observe the concentrations of elemental carbon (EC) and the relationship between the EC concentrations in UFPs and FPs, and to examine the possible emission sources of char and soot that constitute UFPs and FPs in a roadside environment. It was found that EC accounts for 33-37% of total carbon (TC) in FPs, whereas EC accounts for 12-20% of TC in UFPs. Both char-EC and soot-EC account for similar proportions of the total EC concentration in UFPs, while soot-EC accounts for only a small amount of the total EC in FPs. Positive and negative correlations between OC and soot-EC were observed for UFPs and FPs, respectively. The observed positive correlation in the case of UFPs possibly reflects the compactness (high density) of UFPs coated with condensed material, such as unburned fuel or lubricating oil emitted by motor vehicles, whereas the negative correlation in the case of FPs possibly indicates that whether or not the spaces between primary soot particles in FPs can be filled depends on the engine load of diesel vehicles operated near the sampling site. The positive and negative correlations were stronger for UFPs (r(2) = 0.69, n = 29, p < 0.001) and FPs (r(2) = -0.62, n = 29, p < 0.001) when the data collected at wind speeds greater than 2.5 m/s were excluded. The different morphological characteristics of the particles observed by transmission electron microscopy also support the observed correlations between OC and soot-EC. The possible emission of char or char-like particles from motor vehicles was shown and discussed in this study.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2010.07.0061
  DOI ID：10.4209/aaqr.2010.07.0061, ISSN：1680-8584, eISSN：2071-1409, Web of Science ID：WOS:000287418100001
• Basic Study on Chemical Modification of Japanese Cedar Pollen Allergen (Cry j 1) by Air Pollutants and Apoptosis Inducibility of 3-Nitrotyrosine for Hela Cell　　　　　　　　　　　　　　　
  MORITA Jun; WANG Qingyue; GONG Xiumin; NAKAMURA Shinichi; SUZUKI Miho; NAKAJIMA Takuya; SEKIGUCHI Kazuhiko; NAKAJIMA Daisuke; MIWA Makoto
  Earozoru Kenkyu, Volume：27, Number：1, First page：71, Last page：77, 2011
  Recently, prevalence of Japanese cedar pollinosis has been increasing, and it is observed highly in the Kanto area of Japan. As a cause of the high prevalence in Kanto area, we focused attention on 3-nitrotyrosines contained in allergen protein that cause the immune reactions and enhance an immunogenicity of allergen proteins. In this study, we measured the size distribution of airborne Cry j 1 concentrations and the relative quantities of airborne Cry j 1 containing 3-nitrotyrosine; and evaluated an apoptosis inducibility of 3-nitrotyrosine for HeLa cell.
  Cry j 1 were highly observed as fine particles (≦1.1 µm) in the urban atmosphere of Saitama city, Japan. We succeeded for the first time in detecting Cry j 1 containing 3-nitrotyrosine in the urban atmosphere as the probable evidence of chemical modification of Cry j 1 by air pollutants. Cry j 1 that exists in the particle sizes smaller than 7.0 µm contained higher probabilities of 3-nitrotyrosine residues compared with Cry j 1 in the particle sizes larger than 7.0 µm. Moreover, we clarified that 3-nitrotyrosine induces HeLa cell (epidermoid cell) apoptosis.
  From these results, it is suggested that further investigations are needed for the behavior and health effect of Cry j 1 and Cry j 1 containing 3-nitrotyrosine in respirable particles.
  Japan Association of Aerosol Science and Technology, Japanese
  DOI：https://doi.org/10.11203/jar.27.71
  DOI ID：10.11203/jar.27.71, ISSN：0912-2834, CiNii Articles ID：130002080948, CiNii Books ID：AN10041511
• Estimation of Roadside Organic Aerosol Components by Means of Time-of-Flight Aerosol Mass Spectrometry　　　　　　　　　　　　　　　
  HAGINO Hiroyuki; SEKIGUCHI Kazuhiko; SAKAMOTO Kazuhiko
  Earozoru Kenkyu, Volume：27, Number：1, First page：62, Last page：70, 2011
  We intensively monitored gas and aerosol compositions near a national road, Route 463, in Saitama, Japan in March 2010. Submicron aerosol composition was measured with a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) and a multi-angle absorption photometer (MAAP). Gas-phase measurements were performed with a typical chemiluminescence instrument for detecting NO_X and a proton transfer reaction mass spectrometer (PTR-MS) for volatile organic compounds (VOCs). NO_X concentrations were highly correlated with black carbon (BC) concentrations (r=0.919, n=223, p<0.01) near the road; in contrast, NO_X were poorly correlated with organic aerosol (OA) concentrations (r=0.439, n=184, p<0.1). HR-ToF-AMS measurements facilitated the determination of organic-mass-to-carbon ratio (average 1.36, range 1.25-1.50) and oxygen-to-carbon (O/C) ratio (average 0.18, range 0.08-0.29). This study also demonstrates the utility of chemical mass balance (CMB) analysis with SOA and POA mass spectra as source data to determine the apportionment of secondary OA (SOA) and primary OA (POA) within OA and the source contributions. Positive matrix factorization (PMF) analysis apportioned oxygenated OA (OOA) and hydrocarbon-like OA (HOA) within the OA samples. The SOA/OA and OOA/OA ratios obtained by these two models were 34% and 43%, respectively. These results indicate that not only traffic-related sources but also SOA, including aged OA, contributed substantially to OA concentrations observed at the roadside.
  
  Japan Association of Aerosol Science and Technology, Japanese
  DOI：https://doi.org/10.11203/jar.27.62
  DOI ID：10.11203/jar.27.62, ISSN：0912-2834, CiNii Articles ID：130002080947, CiNii Books ID：AN10041511
• Synergistic effects of high-frequency ultrasound on photocatalytic degradation of aldehydes and their intermediates using TiO2 suspension in water　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Chie Sasaki; Kazuhiko Sakamoto
  ULTRASONICS SONOCHEMISTRY, Volume：18, Number：1, First page：158, Last page：163, Jan. 2011, [Reviewed]
  The degradation of model substances, benzaldehyde (C6H5CHO) and formaldehyde (HCHO), were investigated under various conditions, namely, ultrasound (US) irradiation, TiO2 photocatalysis with UV irradiation (UV/TiO2), and the combination of sonophotocatalysis and UV irradiation (US/UV/TiO2), in order to clarify the synergistic effects between US and UV/TiO2. US and UV/TiO2 primarily contribute to the degradation of highly hydrophobic and hydrophilic substances, respectively. However, the degradation rate was found to depend on the chemical properties and concentration of not only the substances initially present, but also their decomposition intermediates. Here, the essential information for accurately evaluating the synergistic effects on reaction rate under US/UV/TiO2 conditions is reported, with a focus on the behavior of decomposition intermediates. (C) 2010 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.ultsonch.2010.04.008
  DOI ID：10.1016/j.ultsonch.2010.04.008, ISSN：1350-4177, Web of Science ID：WOS:000282853200026
• Performance Test of an Inertial Fibrous Filter for Ultrafine Particle Collection and the Possible Sulfate Loss when Using an Aluminum Substrate with Ultrasonic Extraction of Ionic Compounds　　　　　　　　　　　　　　　
  Kyung Hwan Kim; Kazuhiko Sekiguchi; Shinji Kudo; Kazuhiko Sakamoto; Mitsuhiko Hata; Masami Furuuchi; Yoshio Otani; Naoko Tajima
  AEROSOL AND AIR QUALITY RESEARCH, Volume：10, Number：6, First page：616, Last page：624, Dec. 2010, [Reviewed]
  A sampler using inertial fibrous filters (INF) has been recently developed for ultrafine particle collection by impaction and filtration. This new sampler has a low pressure drop (20-30 kPa) and can separate particles smaller than 0.1 mu m with a high sampling flow rate (40 L/min). In this study, sampling performance of the INF sampler was evaluated in comparison with a reference sampler in the field as well as in the laboratory and the possible sulfate ion loss when using aluminum substrates for ion extraction in ultrasonic bath was discovered and investigated. When sampling ultrafine particles (Dp <= 0.1 mu m) such as carbonaceous and ionic species both in the field and in the laboratory, the performance of the INF sampler was similar to that of a reference sampler despite differences of sampling mechanism, cut-point diameter, and substrate proving that the INF sampler can be an alternative for ultrafine particle collection. Underestimation of sulfate concentration appeared to be unavoidable in ultrasonic extractions from aluminum substrates regardless of whether the extraction time was 30 or 90 min. The average sulfate loss during aluminum filter extraction was 45% (+/- 12%; min: 12%; max: 94%). Therefore, ultrasonic extraction from aluminum filters should be avoided to obtain unbiased measurements of sulfate concentration in ambient air or other ion extraction methods should be considered to minimize sulfate loss (dissolution of aluminum ions) from aluminum filters with sufficient extraction efficiency of ionic species.
  The results of this study indicate that the performance of the INF sampler is almost similar to that of the nano-MOUDI sampler for ultrafine particle collection, while advantageous in terms of convenience, and analysis. Furthermore, the INF sampler can collect amounts of ultrafine particles that are sufficient for chemical analysis in a relatively short time, and the particles can be uniformly collected with a quartz fiber filter.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2010.04.0033
  DOI ID：10.4209/aaqr.2010.04.0033, ISSN：1680-8584, Web of Science ID：WOS:000283514000011
• Degradation of organic gases using ultrasonic mist generated from TiO2 suspension　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Daisuke Noshiroya; Misako Handa; Keisuke Yamamoto; Kazuhiko Sakamoto; Norikazu Namiki
  CHEMOSPHERE, Volume：81, Number：1, First page：33, Last page：38, Sep. 2010, [Reviewed]
  The photocatalytic degradation of organic gases with mist particles that were formed by ultrasonic atomization of a TiO2 suspension was performed with three different ultraviolet light sources. Three aromatic volatile organic compounds (VOCs; toluene, p-xylene, and styrene) and aldehydes (formaldehyde and acetaldehyde) were chosen as model organic gases for the degradation experiment. Under UV365 irradiation, toluene was decomposed by a photocatalytic reaction on the surface of mist particles. Under UV254+185 irradiation, the removal efficiency and mineralization ratio of the VOC gases were higher than those under UV365 or UV254 irradiation. Under UV254+185 irradiation, it was found that VOC gases were immediately degraded and converted to water-soluble intermediates by not only direct photolysis but also oxidation by OH radical, since the removal efficiency of several organic gases depended on the reaction rate with OH radical and the primary effect of generated ozone was to complete the mineralization of the intermediates. On the other hand, water-soluble aldehyde gases were rapidly trapped by mist particles before reaction on their surface. Furthermore, water-soluble intermediates that formed via the decomposition of VOC gases were completely trapped in the mist and were not detected at the reactor exit. Therefore, notable secondary particle generation was not observed, even under UV254+185 irradiation. Based on these results as well as the size distribution of the mist droplets, it was found that primarily submicron-scale droplets contributed to the photocatalytic reaction. Lastly, we propose a mechanism for the degradation of organic gaseous pollutants on the surface of mist particles. (C) 2010 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.chemosphere.2010.07.009
  DOI ID：10.1016/j.chemosphere.2010.07.009, ISSN：0045-6535, eISSN：1879-1298, PubMed ID：20705323, SCOPUS ID：77956059223, Web of Science ID：WOS:000282204800006
• Characteristics of PM_<2.5>　　　　　　　　　　　　　　　
  SEKIGUCHI Kazuhiko
  Journal of Japan Society for Atmospheric Environment / Taiki Kankyo Gakkaishi, Volume：45, Number：4, First page：A54, Last page：A60, Jul. 2010
  Japan Society for Atmospheric Environment, Japanese
  DOI：https://doi.org/10.11298/taiki.45.A54
  DOI ID：10.11298/taiki.45.A54, ISSN：1341-4178, CiNii Articles ID：10030703339, CiNii Books ID：AN10512108
• Degradation of VOC gases in liquid phase by photocatalysis at the bubble interface　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Wakana Morinaga; Kazuhiko Sakamoto; Hajime Tamura; Fumio Yasui; Mohammad Mehrjouei; Siegfried Mueller; Detlev Moeller
  APPLIED CATALYSIS B-ENVIRONMENTAL, Volume：97, Number：1-2, First page：190, Last page：197, Jun. 2010, [Reviewed]
  Photocatalytic reactions in the gas phase have a number of disadvantages including the adverse effects of relative humidity, the emission of decomposition intermediates at the reactor exit and the deactivation of the photocatalyst surface by decomposition intermediates In this study, these disadvantages can be overcome using a novel photocatalytic reaction system. Volatile organic compound (VOC) gases were decomposed at the bubble interface in a TiO2 suspension by using TiO2 photocatalysis in the heterogeneous liquid-bubble (LB) phase since the intermediates dissolve into water and then are continuously decomposed regardless of humidity Toluene. p-xylene, styrene and formaldehyde were chosen as model VOC gases to investigate photocatalytic reactivity in the LB phase The removal ratio of VOC gases in the LB phase was equal to or greater than that in the gas phase, although the reactivity in the LB phase depended on the reaction rate of OH radicals and the hydrophobicity of the VOC gases The reaction in the LB phase also depended on the wavelength and intensity of UV light. Specifically, the removal and mineralization ratios were Improved by using shorter wavelengths of UV irradiation. Finally, as a trial experiment, we applied the microbubble technique to this system When VOC gases were introduced into the system as microbubbles. VOC gas was effectively removed and high removal ratios were obtained regardless of the wavelength and intensity UV light. (C) 2010 Elsevier B.V. All rights reserved
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.apcatb.2010.03.039
  DOI ID：10.1016/j.apcatb.2010.03.039, ISSN：0926-3373, eISSN：1873-3883, SCOPUS ID：77953139035, Web of Science ID：WOS:000279124000023
• Development and Performance Evaluation of Air Sampler with Inertial Filter for Nanoparticle Sampling　　　　　　　　　　　　　　　
  Masami Furuuchi; Kazunobu Eryu; Mizuki Nagura; Mitsuhiko Hata; Takaharu Kato; Naoko Tajima; Kazuhiko Sekiguchi; Kensei Ehara; Takafumi Seto; Yoshio Otani
  AEROSOL AND AIR QUALITY RESEARCH, Volume：10, Number：2, First page：185, Last page：192, Apr. 2010, [Reviewed]
  This paper describes the design and evaluation of an ambient air sampler consisting of a four-stage impactor and an inertial filter, for collecting various size fractions, including nano-particles, in a short sampling period. Impactor stages of PM(10)/PM(2.5)/PM(1)/PM(0.5) were successfully devised with a reasonable accuracy in terms of cutoff size and slope of the collection efficiency curves. The designed inertial filter had an aerodynamic cutoff size of d(p50)similar to 65 nm with a satisfactory sharpness in classification. The total pressure drop of the sampler ( hereinafter referred to as a "Nanosampler") was similar to 30 kPa at a flow rate of 40 L/min. The developed Nanosampler has advantages over currently available samplers such as LPI and nano-MOUDI, in terms of portability and loss of semi-volatile components in ultrafine particles by evaporation at a reduced pressure. Furthermore, the size distributions of the ambient particles measured with the Nanosampler compared favorably with those measured by the conventional instruments that are currently available on the market.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2009.11.0070
  DOI ID：10.4209/aaqr.2009.11.0070, ISSN：1680-8584, eISSN：2071-1409, Web of Science ID：WOS:000276310700010
• The Environmental Policy Choice and the Pollution-Haven Hypothesis : Evidence from Regional Comparison in China　　　　　　　　　　　　　　　
  HUANG Zheng; TONOOKA Yutaka; SEKIGUCHI Kazuhiko; WANG Qingyue; SAKAMOTO Kazuhiko
  ENVIRONMENTAL SCIENCE, Volume：23, Number：2, First page：67, Last page：80, Mar. 2010
  China's recent rapid economic growth has continued, and along with it environmental problems have become increasingly apparent. In this study, we analyzed the relationship between regional economic development and environmental problems using environmental Kuznets curves and Pollution-Haven hypothesis. China was divided into two areas and environmental Kuznets curves were drawn for each area. Regional economic developments, and the relation with the three types of environment loads, air pollution, water environment, solid waste problem, were analyzed by the coastal and inland areas in China. In terms of COD, the tendency to the improvement was found. In terms of SO₂ and solid waste, two regions showed the tendency of increasing with the economy growth. With the income elasticity effect, the composition of industry became cleaner in the coastal region than in the inland region. Our findings were that the imbalance of economic development between the coastal and inland areas has aggravated environmental problems, and the gap between economic development and environmental control has generally grown.
  SOCIETY OF ENVIRONMENTAL SCIENCE, JAPAN, Japanese
  DOI：https://doi.org/10.11353/sesj.23.67
  DOI ID：10.11353/sesj.23.67, ISSN：0915-0048, CiNii Articles ID：10026205647, CiNii Books ID：AN10165252
• Decolorization of Wastewater Produced in a Pyrolysis Process by Ozone: Enhancing the Performance of Ozonation　　　　　　　　　　　　　　　
  Mohammad Mehrjouei; Siegfried Mueller; Kazuhiko Sekiguchi; Detlev Moeller
  OZONE-SCIENCE & ENGINEERING, Volume：32, Number：5, First page：349, Last page：354, 2010, [Reviewed]
  This paper shows the results of color removal from a wastewater produced in a plastic pyrolysis process by ozonation. The influence of parameters such as temperature, reactor geometry, UVA, ozone input, and finally spraying of wastewater on performance enhancement of the decolorization process will be discussed. Due to the long residence time of O3 molecules in the gaseous phase, recycling and spraying the wastewater in a pre-filled ozone chamber show a remarkable effect on decreasing the decolorization process time. At the end of this paper, an application of omicro-bubble producero in this field, and its advantages will be introduced.
  TAYLOR & FRANCIS INC, English, Scientific journal
  DOI：https://doi.org/10.1080/01919512.2010.501277
  DOI ID：10.1080/01919512.2010.501277, ISSN：0191-9512, Web of Science ID：WOS:000282584300009
• Comparison of Water-Soluble Organic Components in Size-Segregated Particles between a Roadside and a Suburban Site in Saitama, Japan　　　　　　　　　　　　　　　
  Linfa Bao; Kazuhiko Sekiguchi; Qingyue Wang; Kazuhiko Sakamoto
  AEROSOL AND AIR QUALITY RESEARCH, Volume：9, Number：4, First page：412, Last page：420, Dec. 2009, [Reviewed]
  To clarify the characteristics of the water-soluble organic components in atmospheric aerosols, size-separated aerosol samples were simultaneously collected at a roadside site (R) and a suburban background site (S) in Saitama, Japan, during spring and summer 2007 and winter 2008. Chemical compositions, including water-soluble organic carbon (WSOC), organic carbon, inorganic ionic components, and individual water-soluble organic acids (saturated dicarboxylic acids, unsaturated dicarboxylic acids, ketocarboxylic acids, and dicarbonyls), were analyzed in size-separated samples. The seasonal variation of WSOC in Saitama aerosols was larger than the spatial difference between the two sites, with summer WSOC concentrations being 2.5-2.8 times those in the other seasons. Seasonal average concentrations of the detected organic acids in PM(7.0) were 542 ng/m(3) (R) and 670 ng/m(3) (S). Strong correlations were observed between C(2)-C(5) n-dicarboxylic acids and ambient oxidants. The concentration ratios of individual n-dicarboxylic acids (C(2)-C(5)) to elemental carbon were significantly higher in suburban samples than in roadside samples, indicating that the contribution of secondary formation to these acids was larger in suburban samples. During the warm seasons, the concentrations of sulfate, ammonium, WSOC, and individual acids in fine particles were very high, whereas nitrate, chloride, sodium, and calcium concentrations were higher in coarse particles. Comparisons between the two sites showed that secondary formation contributed more to the total amount of particulate water-soluble organic acids in Saitama aerosols than direct emissions from anthropogenic and natural sources. However, vehicle exhaust was also an important source of dicarboxylic acids in Saitama aerosols, especially in the near-roadside environment.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  DOI：https://doi.org/10.4209/aaqr.2009.03.0021
  DOI ID：10.4209/aaqr.2009.03.0021, ISSN：1680-8584, eISSN：2071-1409, SCOPUS ID：77952815482, Web of Science ID：WOS:000270892800004
• Evaluation of Multichannel Annular Denuders for a Newly Developed Ultrafine Particle Sampling System　　　　　　　　　　　　　　　
  K. Sekiguchi; K. H. Kim; S. Kudo; K. Sakamoto; Y. Otani; T. Seto; M. Furuuchi; F. Yoshikawa; K. Ehara; M. Hirasawa; N. Tajima; T. Kato
  AEROSOL AND AIR QUALITY RESEARCH, Volume：9, Number：1, First page：50, Last page：64, Mar. 2009, [Reviewed]
  Laboratory studies evaluated the gas collection efficiencies and particle transmission efficiencies of 1-, 3-, 5-, and 8-channel denuders under simulated atmospheric conditions with the goal of combining an annular denuder-filter pack (AD-FP) system with a newly developed inertial classification. The multichannel denuders having large surface areas were considered for this AD-FP system since the inertial classification system operates at a flow rate of 40 L/min. Gas collection efficiency was measured with phosphorous acid-coated denuders targeted on ammonia gas. Particle transmission efficiency was measured for ammonium sulfate particles. The denuder-coating procedure and the method for extracting the multichannel denuders are described in detail. Gas collection efficiencies for the 1-, 3-, 5-, and 8-channel denuders were 96.3, 98.6, 98.2, and 98.3% (1-ch < 5-ch, 8-ch, and 3-ch), respectively. The extraction efficiency was greater than 96% for all but the 8-channel denuder (92%). The particle transmission efficiencies for the 1-, 3-, 5-, and 8-channel denuders at 40 L/min were 97.3, 97.4, 94.7, and 93.4% (8-ch < 5-ch < 1-ch and 3-ch), respectively. These results indicate that a 1- or 3- channel denuder can be effectively used in this AD-FP system at a flow rate of 40 L/min.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  ISSN：1680-8584, Web of Science ID：WOS:000269260400004
• Evaluation of Multichannel Annular Denuders for a Newly Developed Ultrafine Particle Sampling System
  K. Sekiguchi; K. H. Kim; S. Kudo; K. Sakamoto; Y. Otani; T. Seto; M. Furuuchi; F. Yoshikawa; K. Ehara; M. Hirasawa; N. Tajima; T. Kato
  AEROSOL AND AIR QUALITY RESEARCH, Volume：9, Number：1, First page：50, Last page：64, Mar. 2009, [Reviewed]
  Laboratory studies evaluated the gas collection efficiencies and particle transmission efficiencies of 1-, 3-, 5-, and 8-channel denuders under simulated atmospheric conditions with the goal of combining an annular denuder-filter pack (AD-FP) system with a newly developed inertial classification. The multichannel denuders having large surface areas were considered for this AD-FP system since the inertial classification system operates at a flow rate of 40 L/min. Gas collection efficiency was measured with phosphorous acid-coated denuders targeted on ammonia gas. Particle transmission efficiency was measured for ammonium sulfate particles. The denuder-coating procedure and the method for extracting the multichannel denuders are described in detail. Gas collection efficiencies for the 1-, 3-, 5-, and 8-channel denuders were 96.3, 98.6, 98.2, and 98.3% (1-ch < 5-ch, 8-ch, and 3-ch), respectively. The extraction efficiency was greater than 96% for all but the 8-channel denuder (92%). The particle transmission efficiencies for the 1-, 3-, 5-, and 8-channel denuders at 40 L/min were 97.3, 97.4, 94.7, and 93.4% (8-ch < 5-ch < 1-ch and 3-ch), respectively. These results indicate that a 1- or 3- channel denuder can be effectively used in this AD-FP system at a flow rate of 40 L/min.
  TAIWAN ASSOC AEROSOL RES-TAAR, English, Scientific journal
  ISSN：1680-8584, SCOPUS ID：67449138259, Web of Science ID：WOS:000269260400004
• 高熱流束マイクロプラズマによるVOCと排気ガス由来超微粒子の同時除去　　　　　　　　　　　　　　　
  並木 則和; 松本 雄紀; 関口 和彦; 長谷川 靖洋
  Volume：2009, First page：857, Last page：857, 2009
  Japanese
  DOI：https://doi.org/10.11491/scej.2009f.0.857.0
  DOI ID：10.11491/scej.2009f.0.857.0, CiNii Articles ID：130004667551
• 超音波霧化法による懸濁液からの超微粒子の発生　　　　　　　　　　　　　　　
  並木 則和; 木部 貴弘; 関口 和彦; 井川 誠司
  Volume：2009, First page：363, Last page：363, 2009
  Japanese
  DOI：https://doi.org/10.11491/scej.2009.0.363.0
  DOI ID：10.11491/scej.2009.0.363.0, CiNii Articles ID：130005041913
• 酸化チタン含有ミストを用いたVOCガス分解処理プロセスの開発　　　　　　　　　　　　　　　
  関口 和彦; 能代谷大介; 山本 圭介; 坂本 和彦
  エアロゾル研究, Volume：24, Number：3, First page：192, Last page：200, 2009, [Reviewed]
  The present work studied the photocatalytic degradation of VOC gas by a mist formed by ultrasonic nebulization of TiO₂ suspension with various wave lengths of UV rays. With UV₃₆₅ irradiation, toluene was decomposed by photocatalytic reaction either on the mist surface or inside it. The toluene removal efficiency increased with the TiO₂ concentration of the suspension. Water-soluble intermediates formed by the decomposition of VOC gases were completely trapped in the mist and were not detected at the reactor exit. Under UV_254+185 irradiation, the complete decomposition efficiency to CO₂ and H₂O was higher than that with UV₃₆₅ or UV₂₅₄ irradiation. With UV_254+185 irradiation, it was found that VOC gases were immediately degraded and converted to water-soluble intermediates by not only direct photolysis but also oxidation by OH radicals, because the removal rate of several organic gases depended on the reaction rate with OH radicals. On the other hand, ozone mainly contributed to complete decomposition of intermediates, because the complete decomposition efficiency of intermediates was decreased without ozone generation under UV_254+185 irradiation in N₂. Finally, we proposed the degradation mechanisms of organic gaseous pollutants on the mist surface.
  Japan Association of Aerosol Science and Technology, Japanese
  DOI：https://doi.org/10.11203/jar.24.192
  DOI ID：10.11203/jar.24.192, ISSN：0912-2834, CiNii Articles ID：130000128968, CiNii Books ID：AN10041511
• 金沢角間地区におけるナノ大気エアロゾル粒子の現状と各種粒子捕集装置の粒子分級特性の比較検討　　　　　　　　　　　　　　　
  畑光彦; 白雲鶴; 古内正美; 福本将秀; 大谷吉生; 関口和彦; 田島奈穂子
  日本海域研究, Volume：40, Number：40, First page：135, Last page：140, 2009
  Japanese
  ISSN：1347-7889, CiNii Articles ID：120001132793, CiNii Books ID：AA11430153
• 金沢外環状道路近傍とトンネル内で採取されたナノ粒子の特性　　　　　　　　　　　　　　　
  畑光彦; 白雲鶴; 吉川文恵; 福本将秀; 大谷吉生; 関口和彦; 田島奈穂子; 古内正美
  日本海域研究, Volume：40, Number：40, First page：31, Last page：36, 2009
  Japanese
  ISSN：1347-7889, CiNii Articles ID：120001132783, CiNii Books ID：AA11430153
• Experimental testing of an annular denuder and filter system to measure gas-particle partitioning of semivolatile bifunctional carbonyls in the atmosphere　　　　　　　　　　　　　　　
  Ricardo Ortiz; Kenji Enya; Kazuhiko Sekiguchi; Kazuhiko Sakamoto
  ATMOSPHERIC ENVIRONMENT, Volume：43, Number：2, First page：382, Last page：388, Jan. 2009, [Reviewed]
  An annular denuder and filter-pack system was tested in combination with the use of the in-tube and on-fiber O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA)-derivatization technique to simultaneously sample and measure gaseous and particulate concentrations of semivolatile bifunctional carbonyl compounds in the atmosphere. Ozone was denuded from the sampling air to avoid oxidation and PFBHA was used as the sorbent by coating the sampling denuders and impregnating the filters. The collection efficiency of the system was evaluated under different conditions in photochemical smog chamber experiments and in field samplings of urban and suburban atmospheres. The effects of concentration level, temperature, and humidity on the collection efficiency were assessed. The system showed average collection efficiencies in one denuder from 81% for pyruvic acid and 82% for glyoxylic acid to 87% for hydroxyacetone and dihydroxyacetone. The capacity of the filters to collect the gaseous fraction that cannot be collected in the denuders was also evaluated, and the system allows a correction for this artifact. The application of this method to chamber experiments and field samplings offers an easy-to-apply technique with good results that can be used to evaluate the partition mechanisms of these compounds in the atmosphere. (C) 2008 Published by Elsevier Ltd.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2008.09.074
  DOI ID：10.1016/j.atmosenv.2008.09.074, ISSN：1352-2310, eISSN：1873-2844, CiNii Articles ID：80020082625, SCOPUS ID：57949114029, Web of Science ID：WOS:000262956500019
• Long-term sulfur emissions and environmental Kuznets curves: Comparison and implications
  Zheng Huang; Yutaka Tonooka; Kazuhiko Sekiguchi; Qingyue Wang; Kazuhiko Sakamoto
  Asian Journal of Atmospheric Environment, Volume：3, Number：1, First page：19, Last page：26, 2009, [Reviewed]
  The environmental Kuznets curve hypothesis assumes an inverted U-shaped relationship between environmental damage and income, and such curves have been used to study how economic growth affects the environment. In this study, we analyzed data for gross domestic product (GDP) per capita and for sulfur emissions in the industrialized countries of the United Kingdom, United States of America, and Japan, as well as data for the developing country of China, to determine the relationship between emissions and income in these countries. Attempts by these countries' governments to incorporate environmental policy considerations into the income-environment relationship were also examined. The potential role of the environmental Kuznets curve as a policy tool was investigated. We determined that, at least in the case of sulfur emissions, policies and institutions significantly reduced environmental degradation in the industrialized countries studied. Furthermore, the environmental Kuznets curve can reliably predict the future relationship between environmental impact and GDP for developing countries.
  Korean Society for Atmospheric Environment, English, Scientific journal
  DOI：https://doi.org/10.5572/ajae.2009.3.1.019
  DOI ID：10.5572/ajae.2009.3.1.019, ISSN：2287-1160, SCOPUS ID：84870031640
• Photocatalytic degradation of gaseous toluene in an ultrasonic mist containing TiO2 particles　　　　　　　　　　　　　　　
  Kazuhiko Sekiguchi; Keisuke Yamamoto; Kazuhiko Sakamoto
  CATALYSIS COMMUNICATIONS, Volume：9, Number：2, First page：281, Last page：285, Feb. 2008, [Reviewed]
  Photocatalytic degradation of toluene gas in a mist formed by ultrasonic atomization of slurried TiO2 was studied under various conditions. Upon irradiation at 365 nm, toluene was decomposed and mineralized by photocatalytic reaction on the mist surface or inside it. The toluene removal ratio increased as the amount of TiO2 in the slurry was increased. Under UV254+185 irradiation, the mineralization ratio was higher than at 365 nm. We propose that under UV254+185 irradiation, toluene was immediately converted to water-soluble intermediates by direct photolysis and O-3 oxidation in the gas phase and that these intermediates were captured in the mist and photocatalytically mineralized to CO and CO2. This paper indicates a new effective utilization of ultrasonic mist and TiO2 photocatalyst. (C) 2007 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.catcom.2007.05.023
  DOI ID：10.1016/j.catcom.2007.05.023, ISSN：1566-7367, eISSN：1873-3905, SCOPUS ID：36249026529, Web of Science ID：WOS:000251761800017
• インパクタフィルタの性能評価と大気中超微小粒子測定への応用　　　　　　　　　　　　　　　
  関口和彦; 石川信幸; 安原正博; 坂本和彦; 大谷吉生; 並木則和
  エアロゾル研究, Volume：23, Number：4, First page：278, Last page：288, 2008, [Reviewed]
  The performance of a newly developed impactor filter sampling system (IF) to classify ultrafine particles (UFP) under atmospheric pressure was evaluated by comparison with a low pressure impactor (LPI) sampler. Tests were carried out in field samplings of atmospheric aerosol. The results showed that the IF is capable of collecting UFP without altering the composition compared to LPI, and the collected amount of OC and EC is 1.4 ∼ 1.6 times higher than LPI sampler. Furthermore, the determination of ionic components like SO₄^2-, NO₃^- and NH₄⁺, indicated that highly-volatile components are volatilized more significantly when using the LPI sampler. The IF was used to sample PM_2.5 and PM_0.1 during summer and winter at the roadside of a busy national road. The chemical composition analysis indicated that only PM_0.1 had seasonal variation on OC composition, whereas ionic components existed mainly in larger particles. Larger particles seemed to be affected by background particles at the roadside, while PM_0.1 were strongly influenced by motor vehicle emissions. Moreover, the relationship between the chemical components in PM_0.1 and particle number concentrations confirmed that homogeneous particle growth dominates in summertime, while heterogeneous particle growth dominates in wintertime.
  Japan Association of Aerosol Science and Technology, Japanese
  DOI：https://doi.org/10.11203/jar.23.278
  DOI ID：10.11203/jar.23.278, ISSN：0912-2834, CiNii Articles ID：10024782249, CiNii Books ID：AN10041511
• Chemical composition of PM2.5 and PM10 and associated polycyclic aromatic hydrocarbons at a roadside and an Urban background area in Saitama, Japan
  Tarek Mohamed Naser; Yuji Yoshimura; Kazuhiko Sekiguchi; Qingyue Wang; Kazuhiko Sakamoto
  Asian Journal of Atmospheric Environment, Volume：2, Number：2, First page：90, Last page：101, 2008, [Reviewed]
  The chemical compositions of PM2.5 and PM10 and associated high-molecular-weight polycyclic aromatic hydrocarbons (PAHs) were investigated during winter and summer at a roadside and an urban background site in Saitama, Japan. The average concentrations of PM2.5 exceeded the United States Environmental Protection Agency standards during both periods. Carbonaceous components were abundant in both the observed and calculated (by means of a mass closure model) chemical composition of PM2.5. Traffic-related pollutants (elemental carbon and highmolecular-weight PAHs) were strongly associated with PM2.5 rather than with larger particles. The mass concentrations of PM2.5, as well as those of EC and PAHs associated with the particles, at the two sites were strongly correlated. Comparison of our data with source profile ratios indicates that diesel-powered vehicles were probably the main source of the measured PAHs. The PAHs concentrations were affected by meteorological conditions during our study. Our results highlight the need for the establishment of standards for PM2.5 in Japan.
  Korean Society for Atmospheric Environment, English, Scientific journal
  DOI：https://doi.org/10.5572/ajae.2008.2.2.090
  DOI ID：10.5572/ajae.2008.2.2.090, ISSN：2287-1160, SCOPUS ID：84858338179
• Influence of nitrogen oxides on heterogeneous uptake and oxidation of sulfur dioxide on yellow sand particles　　　　　　　　　　　　　　　
  Yoichi Horita; Atsuyuki Sorimachi; Hisae Takada; Kazuhiko Sekiguchi; Wang Qingyue; Hidekazu Ishihara; Masataka Nishikawa; Kazuhiko Sakamoto
  PROGRESS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY, VOL I, First page：1272, Last page：1277, 2007, [Reviewed]
  In China, large amounts of sulfur dioxide (SO2) from coal combustion have been emitted with the progression of industrial and economic activities. In addition, since the emissions of nitrogen oxides and hydrocarbons from automobile exhaust and fossil fuel combustion have been increasing, there is the possibility that ozone (O-3) and gaseous nitric acid (HNO3) would be produced through photochemical reactions. Taking into account those circumstances, the evaluation of the uptake extent of acidic gases and oxidants to mineral dust particles may provide interesting information about the transport and fate of such gases. There are some laboratory studies about the heterogeneous reactions of air pollutants on Chinese mineral dust particles. Furthermore, these reports showed that coexistent components might importantly contribute to heterogeneous uptake and/or to oxidation of SO2. On the other hand, there are a few reports about the possibility that yellow sand particles act as chemical reaction sites in the atmosphere, and as carriers of chemical products, on the basis of chemical analysis of the yellow sand particles during the long-range transport from the source to Japan. Therefore, there is the possibility that air pollutants were attached to yellow sand particles and/or reacted with the particles. In order to obtain information about influence, of moisture, NO2, and gaseous nitric acid (HNO3) on heterogeneous reaction of SO2 on Lanzhou soil particles collected in Lanzhou, China, laboratory experiments were performed in the use of a cylindrical flow reactor. We focused uptake and oxidation of SO2 in this study. The uptake of SO2 was estimated by monitoring the concentration of SO2 continuously. As a result, a high reactivity of SO2 with Lanzhou soil particles was shown. However, the uptake of SO2 was controlled in the presence of HNO3 at < 10% RH, which suggests a rapid acidification of the particle surface by HNO3 uptake. At 80%RH, the uptake of SO2 increased significantly in comparison with < 10%RH and had little influence of NO2 and HNO3. The sulfur oxidation was discussed by means of oxidation ratio of sulfur (ORS). Moisture and NO2 increased the ORS values, and a synergic effect between both components was exhibited. This result indicated the contribution Of NO2 and metal components eluted from the particles to oxidation reaction. HNO3 also contributed to acceleration of oxidation at 80%RH. It is considered that the characteristic transformation of the China loess particle surfaces by SO2 uptake might be related significantly to moisture, NO2, and HNO3.
  SCIENCE PRESS BEIJING, English, International conference proceedings
  Web of Science ID：WOS:000252307300238
• Measurement of polycyclic aromatic hydrocarbons in bio-diesel exhaust particles　　　　　　　　　　　　　　　
  Toshinori Shirai; Fumie Mogi; Kazuhiko Sekiguchi; Qingyue Wang; Hideki Kurokawa; Yuji Yoshimura; Kazuhiko Sakamoto
  PROGRESS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY, VOL I, First page：516, Last page：522, 2007, [Reviewed]
  We measured fine particles in the diesel (DF) or bio-diesel fuel (131317) combustion exhaust generated by a diesel power generator (YDG5500B Yanmer) at two different loads (0 and 1500 W). After the dilution of exhausts to 300 times, fine particles were collected with quartz fiber filter and the size-distributions were measured with Scanning Mobility Particle Sizer. Ionic components, organic and elemental carbon, and polycyclic aromatic hydrocarbon (PAHs) were analyzed with lonchromatograph, Thermal Optical Carbon Analyzer, and high-performance liquid chromatograph-fluorescence detector respectively. The chemical compositions and number-size distributions of fine particles were observed at the different combination of DF or BDF and miner, or synthetic lubricant. In the size distributions of diesel and bio-diesel exhaust particles at the different load modes, respective size distribution under low loa condition showed lower mass concentration than high load condition. When using BDF, more organic carbon (OC) was emitted than when using DF without considerable change on number-size distribution of particles, while more elemental carbon (EC) and PAHs were emitted when using DF. In the combination BDF and synthetic lubricating oil, the lowest concentration of EC, total PAHs and respective PAH were observed in the exhaust. These results suggest that 6 exhaust quality from BDF combustion can improve when replacing mineral lubricating oil to synthetic lubricating oil.
  SCIENCE PRESS BEIJING, English, International conference proceedings
  Web of Science ID：WOS:000252307300092
• 都市部高層ビルにおける超微小粒子の炭素成分挙動　　　　　　　　　　　　　　　
  工藤慎治; 関口和彦
  大気環境学会誌, Volume：42, Number：6, First page：369, Last page：376, 2007, [Reviewed]
  In order to clarify the behavior of ultrafine particles (UFP; less than 0.1 ktm) in lower troposphere, measurement was carried out at a high-rise building in Tokyo during summer and winter of 2005. Samplers of impactor filters (PM_0.1) and cyclones (PM_2.5) were set up at the balconies on the 6th and 55th floors, their carbonaceous (organic carbon (OC), elemental carbon (EC)) and ionic components were analyzed. EC concentrations in PM_0.1 and PM_2.5 at different heights indicated the same variation in summer, respectively. Therefore, it can be thought that EC components were diffused to upper atmosphere by air convective mixing. Even if the variation of PM_2.5 EC concentrations in winter at different heights were remarkably different, EC concentrations in PM_0.1 showed the same variation like in summer. These results suggest that EC from automobile exhaust can reach the upper atmosphere regardless of the season due to its high diffusivity, and it can contribute to the UFP formation in upper atmosphere. In summer, UFP indicated high photochemical reactivity because sulfate concentration increased with OC concentration during day time.
  Japan Society for Atmospheric Environment, Japanese
  DOI：https://doi.org/10.11298/taiki1995.42.6_369
  DOI ID：10.11298/taiki1995.42.6_369, ISSN：1341-4178, CiNii Articles ID：110006440427
• 光触媒含有超音波霧を活用した空気浄化技術　　　　　　　　　　　　　　　
  関口和彦; 山本圭介; 坂本和彦
  超音波TECHNO, Volume：19, Number：4, First page：62, Last page：67, 2007
  Japanese
  ISSN：0916-2410, CiNii Articles ID：40015588678, CiNii Books ID：AN10068970
• Ambient air measurements of six bifunctional carbonyls in a suburban area　　　　　　　　　　　　　　　
  Ricardo Ortiz; Hiroyuki Hagino; Kazuhiko Sekiguchi; Qingyue Wang; Kazuhiko Sakamoto
  ATMOSPHERIC RESEARCH, Volume：82, Number：3-4, First page：709, Last page：718, Dec. 2006, [Reviewed]
  Low-molecular-weight carbonyl compounds, generated by photochemical reactions in the atmosphere and found in the exhaust of motor vehicles, have recently come to the attention of researchers because some of them are suspected carcinogens or mutagens. Six bifunctional carbonyl compounds were detected and measured in a suburban site 30 km northwest of the Tokyo metropolitan area. Samples were taken on five sunny days between 2 August and 11 August 2003 with a low-volume denuder and three-filter tandem system using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) as a sorbent. Bifunctional carbonyls were measured by gas chromatography-mass spectrometry after two derivatization processes with PFBHA and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The average total (gas plus particle) concentrations were 162.8 ng m(-3) for pyruvic acid, 113.7 ng m(-3) for methylglyoxal, 36.0 ng m(-3) for glycolaldehyde and 58.6 ng m(-3) for glyoxal. (c) 2006 Published by Elsevier B.V.
  ELSEVIER SCIENCE INC, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosres.2006.02.025
  DOI ID：10.1016/j.atmosres.2006.02.025, ISSN：0169-8095, eISSN：1873-2895, Web of Science ID：WOS:000242926500024
• Investigation of variations in suspended particulate matter with enforcement of regulations on diesel vehicle exhaust in suburban Japan　　　　　　　　　　　　　　　
  ZW Jiang; QY Wang; K Sekiguchi; K Sakamoto
  JSME INTERNATIONAL JOURNAL SERIES B-FLUIDS AND THERMAL ENGINEERING, Volume：49, Number：1, First page：2, Last page：7, Feb. 2006, [Reviewed]
  In the summers of 2003 and 2004, size-separated suspended particulate matter (SPM) samples were collected with a high-volume Andersen air sampler at a site adjacent to Saitama Prefectural Route 57 in Saitama City. This sampling site is in an atmospherically polluted area that is also one of the "Specified Areas concerning Special Measures for Total Emission Reduction of Nitrogen Oxides and Particulate Matter from Automobiles" established in October 2002. We investigated carbonaceous compounds in the SPM before and after the Regulation on Diesel Vehicle Exhaust came into effect in October 2003 in Tokyo Metropolis and Saitama, Chiba, and Kanagawa prefectures. At the sampling site, elemental carbon (EC) in the fine particles (< 2 mu m) was derived mainly from diesel vehicle exhaust emissions, and crustal metals such as Al, Fe, and Mg in the coarse particles (> 2 mu m) were generated as road dust by vehicular traffic and wind. Correlations among chemical components generated by heavy-duty diesel vehicles suggest that the air quality is improving at the sampling site as a result of the enforcement of the Regulations on Diesel Vehicle Exhaust.
  JAPAN SOC MECHANICAL ENGINEERS, English, Scientific journal
  DOI：https://doi.org/10.1299/jsmeb.49.2
  DOI ID：10.1299/jsmeb.49.2, ISSN：1340-8054, CiNii Articles ID：110004086912, Web of Science ID：WOS:000236432800002
• 超微小粒子測定装置(UFPC)を用いた道路近傍および建物屋内外におけるPM2.5および超微小粒子の粒径別数濃度測定　　　　　　　　　　　　　　　
  関口和彦; 鈴木宏保; 安原正博; 根津豊彦; 吉村有史; 坂本和彦
  エアロゾル研究, Volume：21, Number：2, First page：137, Last page：146, 2006, [Reviewed]
  Field measurements of size-resolved particle number concentrations of PM_2.5 and ultrafine particles (UFPs) (<0.3μm) were performed using an ultrafine particle counter (UFPC) at a roadside and indoor / outdoor of a building located about 50m away from the roadside. Similar behavior of both UFP and PM_2.5 were found for number concentrations at all measuring sites, and it was made clear that the wind speed influences UFP concentration more significantly than rainfall. In addition, high correlations between UFP concentration and nitrogen monoxide (NO) and elemental carbon (EC) concentrations indicated that the particles emitted from motor vehicles, particularly diesel emission particles, are transported near the building and penetrated into the indoor space of the building. Furthermore, since the indoor / outdoor ratios (I / O ratios) of UFP and PM_2.5 increased when a fan ventilator was used, it was thought that UFP and PM_2.5 come into the building through the gaps between windows and doors with the walls.
  Japan Association of Aerosol Science and Technology, Japanese
  DOI：https://doi.org/10.11203/jar.21.137
  DOI ID：10.11203/jar.21.137, ISSN：0912-2834, CiNii Articles ID：10018147962, CiNii Books ID：AN10041511
• Hybrid treatment process for gaseous pollutants by coupling UV-C/TiO2 and air washer system　　　　　　　　　　　　　　　
  Jeong J. Y; Sekiguchi K; Saito M; Lee Y. G; Sakamoto K
  Chem. Eng. J., Volume：118, Number：1-2, First page：127, Last page：130, 2006, [Reviewed]
  DOI：https://doi.org/10.1016/j.cej.2005.11.020
  DOI ID：10.1016/j.cej.2005.11.020, CiNii Articles ID：10030508102
• Photodegradation of gaseous volatile organic compounds (VOCs) using TiO2 photoirradiated by an ozone-producing UV lamp: decomposition characteristics, identification of by-products and water-soluble organic intermediates　　　　　　　　　　　　　　　
  J Jeong; K Sekiguchi; W Lee; K Sakamoto
  JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY, Volume：169, Number：3, First page：279, Last page：287, Feb. 2005, [Reviewed]
  The photodegradation of the toluene and benzene with TiO2 (P25) and UV254+185 nm radiation from an ozone-producing UV lamp was studied. The VOCs were decomposed and mineralized efficiently owing to the synergistic effect of photochemical oxidation in the gas phase and photocatalytic oxidation on the TiO2 surface. The conversion levels obtained with UV254+185 nm photoirradiated TiO2 were much higher than those with conventional UV sources (UV365 nm and UV254 nm), which suffer from both catalyst deactivation and the generation of harmful intermediates. The products from the photodegradation of VOCs with the UV254+185 nm photoirradiated TiO2 were mainly mineralized CO2 and CO2 but some water-soluble organic intermediates were also formed under more severe reaction conditions. The water-soluble aldehydes and carboxylic intermediates disappeared from the effluent gas, stream and were detected in the water impingers. These findings suggest that the intermediates can be washed out by conventional gas washing technique, such as wet scrubber. Excess ozone could be easily removed by means of an MnO2 ozone-decomposition catalyst. (C) 2004 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE SA, English, Scientific journal
  DOI：https://doi.org/10.1016/j.jphotochem.2004.07.014
  DOI ID：10.1016/j.jphotochem.2004.07.014, ISSN：1010-6030, CiNii Articles ID：80017186384, Web of Science ID：WOS:000226343300008
• 光触媒を併用した水中有機物質の超音波分解－中間生成物の分解速度からみた光触媒の添加効果－　　　　　　　　　　　　　　　
  関口和彦; 佐々木智恵; 坂本和彦
  超音波TECHNO, Volume：17, Number：4, First page：24, Last page：29, 2005
  Japanese
  ISSN：0916-2410, CiNii Articles ID：40006851166, CiNii Books ID：AN10068970
• Influence of ozone, relative humidity, and flow rate on the deposition and oxidation of sulfur dioxide on yellow sand　　　　　　　　　　　　　　　
  K Sakamoto; H Takada; K Sekiguchi
  ATMOSPHERIC ENVIRONMENT, Volume：38, Number：40, First page：6961, Last page：6967, Dec. 2004, [Reviewed]
  To evaluate the influences of O-3, relative humidity (RH), and flow rate on the reaction between yellow sand and SO2, the SO2 deposition velocity and the oxidation state of sulfur were investigated by means of exposure experiments in a cylindrical flow reactor. Early in the reaction, the deposition velocity was not influenced by the RH or the presence of O-3; as the reaction progressed, however, the deposition velocity increased in the presence of O-3 and at high humidity. The oxidation of sulfur from S(IV) to S(VI) was also enhanced under these conditions. The amount of sulfur oxidation was positively correlated with the amount of deposited O-3. Furthermore, the SO2 deposition velocity increased with increasing flow rate. However, changes in the flow rate had no noticeable effect on the amount Of SO2 oxidation. (C) 2004 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.atmosenv.2004.05.060
  DOI ID：10.1016/j.atmosenv.2004.05.060, ISSN：1352-2310, Web of Science ID：WOS:000225800800006
• Photochemical and photocatalytic degradation of gaseous toluene using short-wavelength UV irradiation with TiO2 catalyst: comparison of three UV sources　　　　　　　　　　　　　　　
  J Jeong; K Sekiguchi; K Sakamoto
  CHEMOSPHERE, Volume：57, Number：7, First page：663, Last page：671, Nov. 2004, [Reviewed]
  The feasibility of the use of short-wavelength UV (254 + 185 nm) irradiation and TiO2 catalyst for photodegradation of gaseous toluene was evaluated. It was clear that the use of TiO2 under 254 + 185 nm light irradiation significantly enhanced the photodegradation of toluene relative to UV alone, owed to the combined effect of photochemical oxidation in the gas phase and photocatalytic oxidation on TiO2. The photodegradation with 254 + 185 nm light irradiation was compared with other UV wavelengths (365 nm (black light blue lamp) and 254 nm (germicidal UV lamp)). The highest conversion and mineralization were obtained with the 254 + 185 nm light. Moreover, high conversions were achieved even at high initial concentrations of toluene. Catalyst deactivation was also prevented with the 254 + 185 nm light. Regeneration experiments with the deactivated catalyst under different conditions revealed that reactive oxygen species played an important role in preventing catalyst deactivation by decomposing effectively the less reactive carbon deposits on the TiO2 catalyst. Simultaneous elimination of photogenerated excess ozone and residual organic compounds was accomplished by using a MnO2 ozone-decomposition catalyst to form reactive species for destruction of the organic compounds. (C) 2004 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.chemosphere.2004.05.037
  DOI ID：10.1016/j.chemosphere.2004.05.037, ISSN：0045-6535, eISSN：1879-1298, CiNii Articles ID：80016942133, PubMed ID：15488929, Web of Science ID：WOS:000224879300016
• 単一光源紫外光の波長選択利用と反応活性種による有機ガス状汚染物質の除去　　　　　　　　　　　　　　　
  関口和彦; 鄭柱泳; 坂本和彦
  エアロゾル研究, Volume：193, Number：3, First page：188, Last page：195, 2004, [Reviewed]
  A new-type of air purification reactor which can simultaneously remove gaseous contaminants and fine particles was developed and evaluated in this study. Two short wavelengths of UV light (185 nm and 254 nm) , irradiated from a single UV source, were separated with an optical filter and used respectively for the gas-to-particle photochemical conversion of organic gases and for the charging of particles generated with the UV/photoelectron method. This technique was applied to remove typical gaseous contaminants in clean rooms, low concentrations of di-n-butyl phthalate (DBP) , dioctyl phthalate (DOP) and low molecular-weight cyclosiloxane (LMCS) . The particles converted from their vapors were effectively removed by the UV/photoelectron method and trapped on an ozone-decomposition catalyst (ODC) , which was used to decompose O₃ formed by 185 nm UV irradiation. Furthermore, the effect of photocatalyst was also investigated for the decomposition of organic gaseous compounds under irradiation of short-wavelength UV light. It became clear that the photocatalyst contributed to promote the mineralization of intermediate products.
  Japan Association of Aerosol Science and Technology, Japanese
  DOI：https://doi.org/10.11203/jar.19.188
  DOI ID：10.11203/jar.19.188, ISSN：0912-2834, CiNii Articles ID：130000125592, CiNii Books ID：AN10041511
• Degradation of toluene with an ozone-decomposition catalyst in the presence of ozone, and the combined effect of TiO2 addition　　　　　　　　　　　　　　　
  K Sekiguchi; A Sanada; K Sakamoto
  CATALYSIS COMMUNICATIONS, Volume：4, Number：5, First page：247, Last page：252, May 2003, [Reviewed]
  The destruction of volatile organic compounds (VOCs) by labile species formed from 03 on an ozone-decomposition catalyst (ODC) was investigated with and without UV irradiation. Toluene was decomposed to CO2 on the ODC surface in the presence Of O-3, even in darkness. A mixed catalyst consisting of the ODC and TiO2 produced higher VOC removals and CO2 conversions, especially in the presence of UV irradiation and high O-3 concentrations. Although humidity hindered the destruction of VOCs by the ODC, this problem was mitigated by using the mixed catalyst. Significant suggestions are made for the utilization of ODCs in VOC destruction. (C) 2003 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/S1566-7367(03)00047-5
  DOI ID：10.1016/S1566-7367(03)00047-5, ISSN：1566-7367, CiNii Articles ID：80016060552, Web of Science ID：WOS:000183342000006
• 廃発泡スチロールとセメントを用いた吸音材上に固定した酸化チタン光触媒によるNOX除去　　　　　　　　　　　　　　　
  利根川義男; 関口和彦; 野村公康; 坂本和彦
  大気環境学会誌, Volume：38, Number：4, First page：227, Last page：235, 2003, [Reviewed]
  Recently in Japan, local air pollution by nitrogen oxides (NOR) emitted from automobiles has attracted considerable attention. Furthermore, noise pollution at heavy traffic roadsides has also attracted attension.Therefore, soundproof walls are constructed by local self-governing bodies for the prevention of noise pollution.
  Therefore, we investigated NOR removal by oxidation with a new catalyst composed of waste polystyrene foam and cement. Nitrogen dioxide (NO₂), normally desorbed as an intermediate of NO oxidation with TiO₂ photocatalyst, was not detected with nitrogen monoxide (NO) oxidation using this catalyst, because of NO₂ adsorption on the porous surface structure of cement. Removal ratio of NO was greatly depended on the contact frequency of NO to the catalyst surface. Therefore, only the thin layer of TiO₂ coated on acoustic material contributed to NO oxidation, because the removal ratio of NO was independent of change of TiO₂ weight coated on the acoustic material. 2.37 × 10^-4mol (7.11 × 10^-3g) of NOR/a cyllindrical catalyst of i.d. 50mm and length 50mm could be removed with this catalyst, until activity of the catalyst declines from 100% to 70%. The high activity of NOR oxidation was not effected by change of the ratio of NO₂ to NOR and SO₂ addition to experimental gas. Environmental load would be reduced with the manufacture of this catalyst, because waste polystyrene foam is recycled.
  Japan Society for Atmospheric Environment, Japanese
  DOI：https://doi.org/10.11298/taiki1995.38.4_227
  DOI ID：10.11298/taiki1995.38.4_227, ISSN：1341-4178, CiNii Articles ID：110003841031
• 短波長紫外光と光触媒を利用した有機ガス物質の水溶性化／噴霧水滴捕集処理技術の開発研究と課題　　　　　　　　　　　　　　　
  関口和彦; 坂本和彦
  会報光触媒, Volume：7, First page：78, Last page：83, 2002
• Development of an automatic continuous analyzer for water-soluble gases in air by combining an artificial lung with an ion chromatograph　　　　　　　　　　　　　　　
  K Sakamoto; M Takeno; K Sekiguchi; O Ishitani; T Fukuyama; M Utiyama
  ATMOSPHERIC ENVIRONMENT, Volume：36, Number：3, First page：441, Last page：448, Jan. 2002, [Reviewed]
  An automatic measurement system for the simultaneous monitoring of sulfur dioxide (SO2) and ammonia (NH3) in air was developed by combining an artificial lung and an ion chromatograph. An artificial lung was used as a new technique for concentrated collection of trace amounts of gaseous pollutants in air. It was found that SO2 and NH3 were effectively absorbed into ultra-pure water in the artificial lung. Collection efficiencies for SO2 and NH3 were 100% and 98%, respectively, at a gas flow rate of 1 l min(-1). and material balances >90% were obtained. No interference from the simultaneous collection of SO2 and NH3 was found. When a 400 ppb standard NH3 gas was measured automatically with this system, the recovery rate was 98%, and the relative standard deviation was 2.7% (n = 8). In the case of a 200 ppb standard SO2 gas, the recovery rate was 87%. and the relative standard deviation was 1.6% (n = 7). Results from the simultaneous measurement of SO2 and NH3 with the automatic system were equally as good as those obtained by measuring a single component at a time. Calibration curves for SO2 and NH3 showed good relationships between concentration and peak intensity. The linear correlation coefficients were 0.997 and 0.998 for SO2 and NH3, respectively. The detection limits of SO2 and NH3 were 0.06 and 0.1 ppb, respectively, in a 401 air volume. The system was tested in air and found to be capable of simultaneous measurement of SO2 and NH3 with a 20 min cycle. (C). 2002 Elsevier Science Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/S1352-2310(01)00421-6
  DOI ID：10.1016/S1352-2310(01)00421-6, ISSN：1352-2310, CiNii Articles ID：80012896928, Web of Science ID：WOS:000173742400005
• Fine particle dry deposition onto a cropland - A trial to estimate deposition velocity　　　　　　　　　　　　　　　
  M Utiyama; T Fukuyama; K Izumi; K Sakamoto; K Sekiguchi; W Kim; A Koyama; M Aoki; H Hara
  WATER AIR AND SOIL POLLUTION, Volume：130, Number：1-4, First page：547, Last page：552, Aug. 2001
  The dry deposition velocity of fine particles is usually on the order of several tenths of cm s(-1), and accordingly, the concentration gradient of particles above the surface is very small. This makes the application of the gradient method to the determination of the particle deposition velocity very difficult. This study is a trial to find a way around this difficulty. The idea is to evaluate the thickness of the molecular diffusion layer, zb by simultaneously measuring the concentration gradient of gaseous species such as SO2; zb is obtained by combining the turbulent and molecular transport equations for the gas. Then the particle deposition velocity is estimated oil the basis of zb and the Brownian diffusion coefficient with an assumption that zb is equal to the thickness of the Brownian diffusion layer. By applying this method to the data collected in a field observation, the velocity of deposition onto a cropland was estimated for submicron particles.
  KLUWER ACADEMIC PUBL, English, Scientific journal
  DOI：https://doi.org/10.1023/A:1013838830637
  DOI ID：10.1023/A:1013838830637, ISSN：0049-6979, CiNii Articles ID：80012789433, Web of Science ID：WOS:000172011900062
• 空気汚染の制御技術について　　　　　　　　　　　　　　　
  坂本和彦; 関口和彦
  CACS FORUM, Volume：21, First page：22, Last page：25, 2001
  Japanese
  CiNii Articles ID：120001686774, CiNii Books ID：AN10402595
• 光触媒による有機物の完全酸化　　　　　　　　　　　　　　　
  坂本和彦; 関口和彦
  クリーンテクノロジー, Volume：11, Number：1, First page：37, Last page：41, 2001
• Removing the typical trace gaseous contaminants in cleanroom using secondary particle formation with short-wavelength UV light and UV/photoelectron charging method　　　　　　　　　　　　　　　
  K Sekiguchi; K Sakamoto; O Ishitani; T Fujii
  INSTITUTE OF ENVIRONMENTAL SCIENCES AND TECHNOLOGY, 1998 PROCEEDINGS - CONTAMINATION CONTROL, First page：67, Last page：72, 1998, [Reviewed]
  In order to develop a new-type of air cleaning technique, gas-to-particle conversion with photochemical reaction under UV (184.9 nm) irradiation and UV (253.7 nm) /photoelectron charging method were applied to removal of outgases such as DBP, DOP and LMCS. When LMCS was added to the air stream with/without DBP or DOP, relatively large particles were formed under W irradiation. The particles generated from LMCS were removed almost completely by UV/photoelectron charging method because of effective multi charging due to its large particle diameter. While, small particles generated from other trace gaseous contaminants were also removed effectively by diffusion adhesion on the honeycomb-catalyst settled to decompose the surplus O-3. Total removal efficiency with diffusion adhesion and electrical collection of the particles charged by UV/photoelectron method was investigated to evaluate the validity of this technique.
  INST ENVIRONMENTAL SCIENCES, English, International conference proceedings
  Web of Science ID：WOS:000074492300010
• Simultaneous removing technique for gaseous pollutants and fine particles using UV/catalyst and UV/photoelectron methods　　　　　　　　　　　　　　　
  Sekiguchi K; Sakamoto K; Fujii T
  Earozoru Kenkyu (J. Aerosol Res.), Jpn., Volume：13, Number：3, First page：222, Last page：229, 1998, [Reviewed]
  DOI：https://doi.org/10.11203/jar.13.222
  DOI ID：10.11203/jar.13.222, ISSN：0912-2834, CiNii Articles ID：10030508122
• UV光と光触媒利用による空気中のガスおよび粒子状汚染物質の除去　　　　　　　　　　　　　　　
  坂本和彦; 関口和彦; 利根川義男
  化学工学シンポジウムシリーズ 62 光および活性化学種の反応工学, First page：15, Last page：20, 1998

• Web書籍エアロゾル用語集(AerosolPedia) https://sites.google.com/view/aerosolpedia/home　　　　　　　　　　　　　　　
  [Contributor]
  Apr. 2022
• 分離技術シリーズ34　　　　　　　　　　　　　　　
  [Contributor]
  Apr. 2020
• 大気環境の事典　　　　　　　　　　　　　　　
  [Contributor]
  Sep. 2019
• Web書籍エアロゾル用語集(AerosolPedia) https://sites.google.com/site/aerosolpedia/home　　　　　　　　　　　　　　　
  [Contributor]
  Aug. 2016
• みんなが知りたいPM2.5の疑問25　　　　　　　　　　　　　　　
  関口 和彦, [Contributor]
  May 2014
• 排水・汚水処理技術集成Vol. 2　　　　　　　　　　　　　　　
  関口 和彦, [Contributor]
  Dec. 2013
• Advances in Chemistry Research. Volume 13　　　　　　　　　　　　　　　
  K. Sekiguchi; K. H. Kim, [Contributor], Chapter 5, Degradation of VOC gases using air-water interface reaction with TiO2 photocatalyst considering treatment of the decomposition intermediates
  Nova Science Publishers, Sep. 2012
• Volatile Organic Compounds　　　　　　　　　　　　　　　
  K. Sekiguchi; K. H. Kim, [Contributor], , Chapter 2, Photocatalytic degradation of VOC gases considering reactor design for the treatment of decomposition intermediates using a short wavelength UV light and water droplets
  Nova Science Publishers, Nov. 2011
• OHラジカル類の生成と応用技術　　　　　　　　　　　　　　　
  関口 和彦, [Contributor]
  Sep. 2008
• Focus on Catalysis Research　　　　　　　　　　　　　　　
  K. Sekiguchi; J. Y. Jeong; K. Sakamoto, [Contributor], Chapter 6, Photochemical and photocatalytic degradation of VOCs using TiO2 photoirradiated by an ozone-producing UV lamp and effective utilization of labile species formed from ozone on an ozone-decomposition catalyst
  Nova Science Publishers, Jun. 2006

• 水中超音波による疎水性有機汚染ガスの分解とナノサイズ吸着剤添加による反応促進　　　　　　　　　　　　　　　
  長谷川真弘, 関口 和彦
  第32回ソノケミストリー討論会, Dec. 2023, [Domestic conference]
• 超音波ミスト界面でのフェントン反応によるVOCガスの分解とその最適化　　　　　　　　　　　　　　　
  横瀬 海斗, 関口 和彦
  第32回ソノケミストリー討論会, Dec. 2023, [Domestic conference]
• 真空紫外線によるVOCガスの迅速分解と超音波ミストによる分解生成物の捕捉と無機化　　　　　　　　　　　　　　　
  樋口 諒, 関口 和彦, 二井 晋
  第32回ソノケミストリー討論会, Dec. 2023, [Domestic conference]
• 超音波ミスト界面でのフェントン反応による気相VOC分解の評価　　　　　　　　　　　　　　　
  横瀬 海斗, 伊藤 北斗, 関口 和彦
  第64回大気環境学会年会, Sep. 2023, [Domestic conference]
• バイオマスとプラスチックの混合燃焼における排出粒子中炭素成分に与えるプラスチック種の影響　　　　　　　　　　　　　　　
  菅原 弘貴, 関口 和彦
  第64回大気環境学会年会, Sep. 2023, [Domestic conference]
• ベトナムハノイで観測されたPM2.5中の水溶性ブラウンカーボンについて　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦
  第64回大気環境学会年会, Sep. 2023, [Domestic conference]
• フィルター上オイルミスト微粒子の真空紫外線照射下における反応性の調査　　　　　　　　　　　　　　　
  森谷 莉里, 関口 和彦, 二井 晋
  第40回エアロゾル科学・技術研究討論会, Aug. 2023, [Domestic conference]
• ナノサンプラーのPM0.1分級カートリッジのSUS繊維分割のための改良　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦
  第40回エアロゾル科学・技術研究討論会, Aug. 2023, [Domestic conference]
• 超音波ミストとゼロ価鉄を用いたCO2還元における諸因子の影響　　　　　　　　　　　　　　　
  山谷 大和, 関口 和彦
  第40回エアロゾル科学・技術研究討論会, Aug. 2023, [Domestic conference]
• 室内空間におけるp-DCB蒸気からの二次および三次有機エアロゾル生成の評価　　　　　　　　　　　　　　　
  山田 惇, 菊川 瑠美, 前野 禅, 並木 則和, 鍵 直樹, 関口 和彦
  第40回エアロゾル科学・技術研究討論会, Aug. 2023, [Domestic conference]
• Assessment of carbonaceous ultrafine particles in Kuala Lumpur, Malaysia　　　　　　　　　　　　　　　
  Y. Fujii, Y. Matsunaga, N. Takenaka, Md Firoz Khan, K. Sekiguchi, Mohd Talib Latif
  Abstracts of the 13th International Conference on Carbonaceous Particles in the Atmosphere (ICCPA) 2023, Jul. 2023, [International conference]
• エキシマランプと低圧水銀ランプを用いたVOC ガス分解特性の比較　　　　　　　　　　　　　　　
  樋口 諒, 関口 和彦
  第2回環境化学物質3学会合同大会（第31回環境化学討論会）, Jun. 2023, [Domestic conference]
• 過炭酸ナトリウムを用いた新たな過酸化水素ガス発生手法の検討　　　　　　　　　　　　　　　
  肱岡 泰陽, 関口 和彦, 安井 文男
  第2回環境化学物質3学会合同大会（第31回環境化学討論会）, Jun. 2023, [Domestic conference]
• PM2.5中の水溶性ブラウンカーボンに対するバイオマス燃焼の影響－ベトナムハノイにおける観測事例　　　　　　　　　　　　　　　
  黒土 優肱, 関口 和彦
  第2回環境化学物質3学会合同大会（第31回環境化学討論会）, May 2023, [Domestic conference]
• SPC/固体酸法を用いた実用レベルのH2O2ガス発生手法　　　　　　　　　　　　　　　
  安井 文男, 武石 義人, 菅田 大助, 関口 和彦
  第40回空気清浄とコンタミネーションコントロール研究大会, Apr. 2023, [Domestic conference]
• 重金属ナノ粒子が添加された光触媒粒子を含有する超音波霧化液滴を用いた揮発性有機化合物（VOC）の光触媒分解の向上　　　　　　　　　　　　　　　
  前野 禅, 西谷 実華, 並木 則和, 関口 和彦, 鍵 直樹
  Apr. 2023, [Domestic conference]
• 真空紫外エキシマランプを用いたガス状／粒子状有機汚染物質の分解　　　　　　　　　　　　　　　
  関口 和彦, 樋口 諒, 森谷 莉里
  第40回空気清浄とコンタミネーションコントロール研究大会, Apr. 2023, [Domestic conference]
• 室内空間におけるp-DCB蒸気からの二次および三次有機エアロゾル生成の把握　　　　　　　　　　　　　　　
  山田 惇, 菊川 留美, 並木 則和, 鍵 直樹, 関口 和彦
  第40回空気清浄とコンタミネーションコントロール研究大会, Apr. 2023, [Domestic conference]
• 水中超音波による気相有機汚染物質の分解と添加剤による反応促進　　　　　　　　　　　　　　　
  長谷川真弘, 関口 和彦
  第31回ソノケミストリー討論会, Oct. 2022, [Domestic conference]
• 超音波を用いた炭酸塩からの二酸化炭素の還元　　　　　　　　　　　　　　　
  緒方大輝, 関口 和彦
  第31回ソノケミストリー討論会, Oct. 2022, [Domestic conference]
• 室内光照射下における二酸化塩素ガスからのSOA生成とその含有成分の調査　　　　　　　　　　　　　　　
  堂畑幸太郎, 関口 和彦
  第63回大気環境学会年会, Sep. 2022, [Domestic conference]
• Evaluation of carbonaceous aerosols and water-soluble inorganic ions in ultrafine and fine particles during winter in urban areas of Vietnam　　　　　　　　　　　　　　　
  T. T. Huyen, K. Sekiguchi, L. B. Thuy, N. T. Dung
  Abstracts of the 11th International Aerosol Conference 2022, Sep. 2022, [International conference]
• ベトナムハノイ道路近傍におけるPM0.1、PM2.5中化学成分の季節変動と粒子成長　　　　　　　　　　　　　　　
  黒土 優太, Truong Thi Huyen, 関口 和彦
  第63回大気環境学会年会, Sep. 2022, [Domestic conference]
• Characteristics of indoor and outdoor ultrafine and fine particles in a residential house in Hanoi, Vietnam　　　　　　　　　　　　　　　
  ruong Thi Huyen, K. Sekiguchi, Trung-Dung Nghiem
  Abstracts of the 2nd Vietnam Conference on Earth and Environmental Sciences (VCEES), Aug. 2022, [International conference]
• Evaluation of nitrate formation process on atmospheric particles during high PM2.5 episodes in northern Vietnam　　　　　　　　　　　　　　　
  Y. Kurotsuchi, K. Sekiguchi, N. T. Dung, N. T. T. Thuy, P. C. Thuy
  Abstracts of the 2nd Vetnam Conference on Earth and Environmental Sciences (VCEES), Aug. 2022, [International conference]
• 超音波ミストを用いたフェントン反応の気相応用に関する検討　　　　　　　　　　　　　　　
  伊藤 北斗, 関口 和彦
  第39回エアロゾル科学・技術研究討論会, Aug. 2022, [Domestic conference]
• ベトナムハノイにおけるPM2.5中水溶性ブラウンカーボンに対するバイオマス燃焼の影響　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦
  第39回エアロゾル科学・技術研究討論会, Aug. 2022, [Domestic conference]
• 真空紫外線を用いたフィルター上オイルミスト微粒子の分解　　　　　　　　　　　　　　　
  森谷 莉里, 関口 和彦, 二井 晋
  第39回エアロゾル科学・技術研究討論会, Aug. 2022, [Domestic conference]
• 430kHz超音波による反応性ミストの生成と定量　　　　　　　　　　　　　　　
  小谷 涼太, 水田 敬, 関口 和彦, 二井 晋
  第59回化学関連支部合同九州大会, Jul. 2022, [Domestic conference]
• 関東圏におけるPM0.1中のレボグルコサン濃度の通年観測　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 熊谷貴美代
  環境化学物質3学会合同大会（第30回環境化学討論会）, Jun. 2022, [Domestic conference]
• ファインバブル化導入によるVOC ガスとナノ粒子の水中捕捉処理　　　　　　　　　　　　　　　
  関口 和彦, 改發 彬浩, 安井 文男
  環境化学物質3学会合同大会（第30回環境化学討論会）, Jun. 2022, [Domestic conference]
• 水中超音波による有機汚染ガスの分解と吸着剤による反応促進　　　　　　　　　　　　　　　
  長谷川真弘, 岡田 暁, 関口 和彦
  環境化学物質3学会合同大会（第30回環境化学討論会）, Jun. 2022, [Domestic conference]
• フェントン反応の最適条件の調査および空気浄化手法への応用　　　　　　　　　　　　　　　
  伊藤 北斗, 関口 和彦
  環境化学物質3学会合同大会（第30回環境化学討論会）, Jun. 2022, [Domestic conference]
• 屋内環境条件下における二酸化塩素ガスからのSOA生成機構の調査　　　　　　　　　　　　　　　
  堂畑幸太郎, 関口 和彦
  環境化学物質3学会合同大会（第30回環境化学討論会）, Jun. 2022, [Domestic conference]
• Carbonaceous and ionic components in ultrafine particles and fine particles measured in different microenvironments in an urban area, Vietnam　　　　　　　　　　　　　　　
  Truong Thi Huyen, K. Sekiguchi
  Abstracts of the 12nd Asian Aerosol Conference 2022, Jun. 2022, [International conference]
• Enhancement of photocatalytic degradation of volatile organic compounds (VOCs) using ultrasonically generated droplets containing TiO2 Particles by adding nano-sized heavy-metal particles　　　　　　　　　　　　　　　
  M. Nishitani, N. Namiki, K. Sekiguchi, N. Kagi
  Abstracts of the 12nd Asian Aerosol Conference 2022, Jun. 2022, [International conference]
• Characteristics of Ultrafine Particles in Kuala Lumpur, Malaysia Influenced by Indonesian Peatland Fires　　　　　　　　　　　　　　　
  Y. Fujii, F. Khan, Y. Matsunaga, N. Takenaka, K. Sekiguchi, M. T. Latif
  Abstracts of the 12nd Asian Aerosol Conference 2022, Jun. 2022, [International conference]
• 光触媒粒子含有超音波霧化液滴による揮発性機合物（VOC）の分解の促進　　　　　　　　　　　　　　　
  西谷 実華, 並木 則和, 関口 和彦, 鍵 直樹
  第39回空気清浄とコンタミネーションコントロール研究大会, Apr. 2022, [Domestic conference]
• Seasonal variation of size fractionated particulate matter in residential houses in urban area in Vietnam: relationship of indoor and outdoor particulate matter and mass size distribution　　　　　　　　　　　　　　　
  L. H. T. Vo, M. Yoneda, N. T. Dung, K. Sekiguchi, Y. Fujitani, Y. Shimada
  Proceedings of the 2nd International Conference on Civil and Environmental Engineering, Jan. 2022, [International conference]
• Seasonal variation of size fractionated particulate matter in residential houses in urban area in Vietnam: relationship of indoor and outdoor particulate matter and mass size distribution　　　　　　　　　　　　　　　
  L. H. T. Vo, M. Yoneda, N. T. Dung, K. Sekiguchi, Y. Fujitani, Y. Shimada
  Proceedings of the 2nd International Conference on Civil and Environmental Engineering, Jan. 2022, [Invited], [International conference]
• Investigation into generation of nanosized mist from ultrasonic atomization by compering particle size distributions　　　　　　　　　　　　　　　
  S. Tokuda, K. Sekiguchi, S. Nii
  Abstracts of the ESS-JSS-AOSS 1st Joint Sonochemistry Conference (Online), Nov. 2021, [International conference]
• 重金属ナノ粒子を添加したTiO2粒子含有超音波霧化液滴による揮発性有機化合物(VOC)の光触媒分解の促進　　　　　　　　　　　　　　　
  西谷 実華, 並木 則和, 関口 和彦, 鍵 直樹
  第30回ソノケミストリー討論会, Oct. 2021, [Domestic conference]
• メッシュネブライザーミストの物性評価と活性種運搬の可能性　　　　　　　　　　　　　　　
  河合 透生, 関口 和彦, 大内 努, 杉山 晋
  第30回ソノケミストリー討論会, Oct. 2021, [Domestic conference]
• 超音波ミストを用いたフェントン反応の気相応用に関する検討　　　　　　　　　　　　　　　
  伊藤 北斗, 関口 和彦
  第30回ソノケミストリー討論会, Oct. 2021, [Domestic conference]
• ベトナムハノイにおける粒子中化学成分の昼夜別挙動　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 熊谷貴美代, 藤谷 雄二, Nghiem Dung, Ly Thuy
  第62回大気環境学会年会, Sep. 2021, [Domestic conference]
• 過酸化水素水を用いない過酸化水素ガス発生手法の検討　　　　　　　　　　　　　　　
  近藤 直希, 岡田 暁, 関口 和彦, 安井 文男, 馬場 航哉
  第62回大気環境学会年会, Sep. 2021, [Domestic conference]
• ファインバブル化手法を用いた高濃度VOCガスの液中捕捉処理　　　　　　　　　　　　　　　
  改發 彬浩, 関口 和彦, 安井 文男
  第62回大気環境学会年会, Sep. 2021, [Domestic conference]
• 屋内環境条件下における二酸化塩素ガスからのSOA 生成能の調査　　　　　　　　　　　　　　　
  関口 和彦,堂畑幸太郎
  第38回エアロゾル科学・技術研究討論会, Aug. 2021, [Domestic conference]
• 重金属ナノ粒子添加によるTiO2粒子含有超音波霧化液滴を用いた揮発性有機化合物（VOC）の光触媒分解の向上　　　　　　　　　　　　　　　
  西谷 実華, 並木 則和, 関口 和彦, 鍵 直樹
  第38回エアロゾル科学・技術研究討論会, Aug. 2021, [Domestic conference]
• 超音波照射による気液界面での物理化学的効果を用いたガス状トルエンの除去とそのメカニズム　　　　　　　　　　　　　　　
  関口 和彦, 岡田 暁
  第38回空気清浄とコンタミネーションコントロール研究大会, Apr. 2021, [Domestic conference]
• 過炭酸ナトリウムを用いた過酸化水素ガスの発生（その1）－温度と流量制御による高濃度発生条件の検討－　　　　　　　　　　　　　　　
  関口 和彦, 岡田 暁, 近藤 直希, 安井 文男, 馬場 航哉
  第38回空気清浄とコンタミネーションコントロール研究大会, Apr. 2021, [Domestic conference]
• 過炭酸ナトリウムを用いた過酸化水素ガスの発生（その2）－数値シミュレーションを用いた発生装置の設計及び検討－　　　　　　　　　　　　　　　
  馬場 航哉, 安井 文男, 岡田 暁, 近藤 直希, 関口 和彦
  第38回空気清浄とコンタミネーションコントロール研究大会, Apr. 2021, [Domestic conference]
• 重金属粒子添加によるTiO2粒子含有超音波霧化液滴を用いた揮発性有機化合物（VOC）の光触媒分解　　　　　　　　　　　　　　　
  西谷 実華, 並木 則和, 中山 良一, 関口 和彦, 鍵 直樹
  第38回空気清浄とコンタミネーションコントロール研究大会, Apr. 2021, [Domestic conference]
• Ambient nanoparticles in Hanoi: Level, chemical composition and source apportionment　　　　　　　　　　　　　　　
  Trung-Dung Nghiem, Thu Thuy Nguyen, K. Sekiguchi, Minh-Thang Nguyen
  Abstracts of the Joint Workshop on the 8th East Asia Nanoparticle Monitoring Network (EA-NanoNet-8) and the 8th Workshop on Environmental Issues related to Agriculture and Agro-industries in South East Asia (EIAA-8), Mar. 2021, [International conference]
• ガス状VOC処理への超音波気液界面反応の応用と機構解明　　　　　　　　　　　　　　　
  岡田 暁, 関口 和彦
  第29回ソノケミストリー討論会, Sep. 2020, [Domestic conference]
• 超音波霧化における生成ナノミストの粒径分布データの精度評価　　　　　　　　　　　　　　　
  徳田 珠李, 関口 和彦, 二井 晋
  第29回ソノケミストリー討論会, Sep. 2020, [Domestic conference]
• 多孔質PTFE チューブとUV/超音波ミストを用いた空気浄化手法　　　　　　　　　　　　　　　
  関口 和彦, 竹村 草太
  第61回大気環境学会年会, Sep. 2020, [Domestic conference]
• ファインバブル発生器を用いたVOC ガスの液相捕捉技術　　　　　　　　　　　　　　　
  関口 和彦, 改發 彬浩, 安井 文男
  第61回大気環境学会年会, Sep. 2020, [Domestic conference]
• 二酸化塩素ガス存在下でのVOC ガスからの粒子生成　　　　　　　　　　　　　　　
  関口 和彦, 中村駿太朗
  第61回大気環境学会年会, Sep. 2020, [Domestic conference]
• 超音波照射で霧化したTiO2粒子含有液滴を用いた揮発性有機化合物（VOC）の光触媒分解　　　　　　　　　　　　　　　
  並木 則和, 木村 美結, 中山 良一, 関口 和彦, 鍵 直樹
  第37回エアロゾル科学・技術研究討論会, Aug. 2020, [Domestic conference]
• ベトナム北部地域において観測された粒子生成プロセス　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 今野 創太, 熊谷貴美代, 松見 豊, 藤谷 雄二, Nghiem Trung Dung, Ly Bich Thuy, Pham Chau Thuy
  第37回エアロゾル科学・技術研究討論会, Aug. 2020, [Domestic conference]
• 超音波照射で生成したTiO2粒子含有液滴を用いた揮発性有機化合物（VOC）の光触媒分解　　　　　　　　　　　　　　　
  並木 則和, 木村 美結, 中山 良一, 関口 和彦, 鍵 直樹
  第37回空気清浄とコンタミネーションコントロール研究大会, Apr. 2020, [Domestic conference]
• 超音波照射によるガス状VOC処理手法の検討　　　　　　　　　　　　　　　
  岡田 暁, 関口 和彦
  第37回空気清浄とコンタミネーションコントロール研究大会, Apr. 2020, [Domestic conference]
• ベンチュリー式ファインバブル発生器を用いた気相汚染物質の液相補捉　　　　　　　　　　　　　　　
  関口 和彦, 改發 彬浩, 安井 文男
  第37回空気清浄とコンタミネーションコントロール研究大会, Apr. 2020, [Domestic conference]
• 過炭酸ナトリウムを用いた過酸化水素ガス発生手法の検討　　　　　　　　　　　　　　　
  近藤 直希, 関口 和彦, 安井 文男
  第37回空気清浄とコンタミネーションコントロール研究大会, Apr. 2020, [Domestic conference]
• 塩含有水を用いた超音波霧化液滴による浮遊超微粒子の捕集　　　　　　　　　　　　　　　
  金子 瑠星, 中山 良一, 並木 則和, 関口 和彦, 二井 晋
  第37回空気清浄とコンタミネーションコントロール研究大会, Apr. 2020, [Domestic conference]
• 河川におけるPPCPs の発生源の推定と流下過程における光分解に関する研究　　　　　　　　　　　　　　　
  菅原 悠太, 竹峰 秀祐, 関口 和彦,三小田憲史
  第54回水環境学会年会, Mar. 2020, [Domestic conference]
• 多孔質PTFEチューブとUV/超音波ミストを用いた有機汚染ガスの分解処理　　　　　　　　　　　　　　　
  竹村 草太, 関口 和彦, 三小田憲史, 二井 晋, 並木 則和
  第28回ソノケミストリー討論会, Nov. 2019, [Domestic conference]
• 水中超音波照射のガス状有機汚染物質除去への応用　　　　　　　　　　　　　　　
  岡田 暁, 関口 和彦, 三小田憲史
  第28回ソノケミストリー討論会, Nov. 2019, [Domestic conference]
• Size-segregated chemical characteristics of atmospheric suspended particles in Hanoi, Vietnam　　　　　　　　　　　　　　　
  S. Konno, K. Sekiguchi, Y. Kurotsuchi, K. Sankoda, Y. Matsumi, K. Kumagai, T. Fujino, H. Yoshikado, Y. Fujitani, N. T. Dung, L. B. Thuy, N. T. T. Thuy, P. C. Thuy
  Abstracts of the 15th International Conference on Atmospheric Sciences and Applications to Air Quality (ASAAQ) 2019, Oct. 2019, [International conference]
• Removal of VOC gas by ultrasonic irradiation　　　　　　　　　　　　　　　
  A. Okada, K. Sekiguchi, K. Sankoda
  Abstracts of the 15th International Conference on Atmospheric Sciences and Applications to Air Quality (ASAAQ) 2019, Oct. 2019, [International conference]
• Characteristics of carbonaceous aerosols in Hanoi, Vietnam　　　　　　　　　　　　　　　
  R. Yamaguchi, K. Sekiguchi, N. T. Dung, N. T. T. Thuy, H. Kuwabara, Y. Fujitani, K. Kumagai, K. Sankoda, K. H. Kim, Q. Wang
  Abstracts of the 15th International Conference on Atmospheric Sciences and Applications to Air Quality (ASAAQ) 2019, Oct. 2019, [International conference]
• 開発した小型PM2.5 計測器のアジア各国での観測結果：ベトナム、インド、インドネシア、モンゴル、マレーシアなど　　　　　　　　　　　　　　　
  松見 豊, 中山 智喜, 山崎 高幸, 岡本 渉, 関口 和彦, 林田佐智子, 川崎 昌博, 内藤 大輔, 甲山 治
  第60回大気環境学会年会, Sep. 2019, [Domestic conference]
• ベトナムハノイ周辺3地点での高濃度大気汚染時におけるPM中の粒径別化学組成　　　　　　　　　　　　　　　
  今野 創太, 黒土 優太, 関口 和彦, 三小田憲史, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第60回大気環境学会年会, Sep. 2019, [Domestic conference]
• ベトナム、ハノイ周辺地域における粒子状物質の測定 (1) ハノイ市街地におけるPM2.5の季節変化　　　　　　　　　　　　　　　
  関口 和彦, 山口 良介, 黒土 優太, 今野 創太, 三小田憲史, 松見 豊, 熊谷貴美代, 藤野 毅, 吉門 洋, 藤谷 雄二
  第60回大気環境学会年会, Sep. 2019, [Domestic conference]
• ベトナム、ハノイ周辺地域における粒子状物質の測定 (2) 炭素、イオン、金属成分の粒径別特徴　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 今野 創太, 熊谷貴美代, 三小田憲史, 松見 豊, 藤野 毅, 吉門 洋, 藤谷 雄二
  第60回大気環境学会年会, Sep. 2019, [Domestic conference]
• ベトナム、ハノイ周辺地域における粒子状物質の測定 (3) 有機マーカー成分の粒径別特徴　　　　　　　　　　　　　　　
  熊谷貴美代, 関口 和彦, 今野 創太, 黒土 優太, 三小田憲史, 藤野 毅, 松見 豊, 吉門 洋, 藤谷 雄二
  第60回大気環境学会年会, Sep. 2019, [Domestic conference]
• ベトナム、ハノイ周辺地域における粒子状物質の測定 (4) PAHsを指標とした粒子状物質の水圏への移行　　　　　　　　　　　　　　　
  三小田憲史, 関口 和彦, 石川 冴夏, 安藤 巧, 黒土 優太, 今野 創太, 熊谷貴美代, 藤野 毅, 松見 豊, 吉門 洋, 藤谷 雄二
  第60回大気環境学会年会, Sep. 2019, [Domestic conference]
• ベトナムハノイにおけるPM2.5およびPM0.1中化学成分の季節別特徴　　　　　　　　　　　　　　　
  関口 和彦, 山口 良介, 黒土 優太, 今野 創太, 三小田憲史, 松見 豊, 熊谷貴美代, 藤野 毅, 吉門 洋, 藤谷 雄二, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第36回エアロゾル科学・技術研究討論会, Sep. 2019, [Domestic conference]
• ベトナム北部3地点での高濃度日におけるPMの粒径別組成　　　　　　　　　　　　　　　
  今野 創太, 黒土 優太, 関口 和彦, 三小田憲史, 松見 豊, 熊谷貴美代, 藤野 毅, 吉門 洋, 藤谷 雄二, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第36回エアロゾル科学・技術研究討論会, Sep. 2019, [Domestic conference]
• ベトナム・ハノイにおける小型PM2.5計測器による長期多点観測で見えてくるもの　　　　　　　　　　　　　　　
  松見 豊, 中山 智喜, 関口 和彦, 今野 創太, 黒土 優太, 三小田憲史, 藤野 毅, 熊谷貴美代, 吉門 洋, 藤谷 雄二, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第36回エアロゾル科学・技術研究討論会, Sep. 2019, [Domestic conference]
• ハノイ大気境界層の特徴とPM2.5の日変動　　　　　　　　　　　　　　　
  藤野 毅, 関口 和彦, 三小田憲史, 山口 航平, 松見 豊, 熊谷貴美代, 藤谷 雄二, 吉門 洋, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第36回エアロゾル科学・技術研究討論会, Sep. 2019, [Invited], [Domestic conference]
• ベトナムハノイにおける大気エアロゾル中有機成分の特徴　　　　　　　　　　　　　　　
  熊谷貴美代, 関口 和彦, 今野 創太, 黒土 優太, 三小田憲史, 藤野 毅, 松見 豊, 吉門 洋, 藤谷 雄二
  第36回エアロゾル科学・技術研究討論会, Sep. 2019, [Domestic conference]
• 家庭用品由来二成分系VOCからの室内二次有機エアロゾル(ISOA)の生成・変質プロセスの把握とその処理　　　　　　　　　　　　　　　
  並木 則和, 古屋 郁美, 中山 良一, 鍵 直樹, 関口 和彦
  第36回エアロゾル科学・技術研究討論会, Sep. 2019, [Domestic conference]
• 超音波照射によるガス状VOC処理手法の開発　　　　　　　　　　　　　　　
  岡田 暁, 関口 和彦, 三小田憲史
  第60回大気環境学会年会, Sep. 2019, [Domestic conference]
• ベトナム北部三地点における大気エアロゾル中金属成分の粒径別特徴　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 今野 創太, 三小田憲史, 熊谷貴美代, 松見 豊, 藤野 毅, 吉門 洋, 藤谷 雄二, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第36回エアロゾル科学・技術研究討論会, Sep. 2019, [Domestic conference]
• 芳香族硫黄化合物の酸化的脱硫反応によるディーゼル燃料の高品質化　　　　　　　　　　　　　　　
  Vereshchagin Konstantin, 山川 哲矢, 荻原 仁志, 黒川 秀樹, 関口 和彦
  第8回 JACI/GSCシンポジウム, Jun. 2019, [Domestic conference]
• 多孔質PTFE チューブと超音波ミストを用いた有機汚染ガスの分解　　　　　　　　　　　　　　　
  関口 和彦, 竹村 草太, 三小田憲史, 二井 晋, 並木 則和
  第36回空気清浄とコンタミネーションコントロール研究大会, Apr. 2019, [Domestic conference]
• 超音波霧化と促進酸化手法を用いた水中VOCs の完全分解　　　　　　　　　　　　　　　
  関口 和彦, 小野 雄誠, 三小田憲史, 二井 晋, 並木 則和
  第36回空気清浄とコンタミネーションコントロール研究大会, Apr. 2019, [Domestic conference]
• 酸化チタンを含有する超音波霧化液滴を用いた揮発性有機化合物（VOC）の光触媒分解　　　　　　　　　　　　　　　
  木村 美結, 岡出 裕介, 中山 良一, 並木 則和, 関口 和彦, 鍵 直樹
  第36回空気清浄とコンタミネーションコントロール研究大会, Apr. 2019, [Domestic conference]
• 超音波霧化液滴の帯電量分布測定と液滴を用いた浮遊超微粒子の捕集　　　　　　　　　　　　　　　
  水島 友也, 広野 加奈, 中山 良一, 並木 則和, 関口 和彦, 二井 晋
  第36回空気清浄とコンタミネーションコントロール研究大会, Apr. 2019, [Domestic conference]
• 家庭用品由来二成分系VOC からの室内二次有機エアロゾル（ISOA）の生成・変質過程の把握とその処理　　　　　　　　　　　　　　　
  並木 則和, 古屋 郁美, 中山 良一, 鍵 直樹, 関口 和彦
  第36回空気清浄とコンタミネーションコントロール研究大会, Apr. 2019, [Domestic conference]
• 水環境中におけるPPCPsの直接・間接光分解性の評価　　　　　　　　　　　　　　　
  三小田憲史, 菅原 悠太, 小林 淳, 関口 和彦
  第53回水環境学会年会, Mar. 2019, [Domestic conference]
• 都市河川における消毒副生成物前駆体および生成能の調査　　　　　　　　　　　　　　　
  山本千恵子, 三小田憲史, 池田 和弘, 関口 和彦, 王 青躍
  第55回環境工学研究フォーラム, Dec. 2018, [Domestic conference]
• 複数の可視光応答型光触媒種を用いた超音波光触媒反応に対するソノルミネッセンス発光の影響　　　　　　　　　　　　　　　
  高橋 佑佳, 関口 和彦, 三小田憲史
  第27回ソノケミストリー討論会, Nov. 2018, [Domestic conference]
• 過炭酸ナトリウムをH2O2供給源として用いたAOPによるVOC分解に関する研究　　　　　　　　　　　　　　　
  泉 俊輝, 関口 和彦, 三小田憲史, 安井 文男
  第27回ソノケミストリー討論会, Nov. 2018, [Domestic conference]
• 多孔質PTFEチューブと超音波ミストを用いた有機汚染ガスの分解　　　　　　　　　　　　　　　
  竹村 草太, 関口 和彦, 三小田憲史, 並木 則和, 二井 晋
  第27回ソノケミストリー討論会, Nov. 2018, [Domestic conference]
• 超音波霧化を導入したAOPによる水中アルデヒド類の完全分解　　　　　　　　　　　　　　　
  小野 雄誠, 関口 和彦, 三小田憲史, 二井 晋, 並木 則和
  第27回ソノケミストリー討論会, Nov. 2018, [Domestic conference]
• EEM-PARAFACによる水質評価：消毒副生成物生成能をもつ溶存有機物の河川挙動　　　　　　　　　　　　　　　
  山本千恵子, 三小田憲史, 関口 和彦, 王 青躍
  第21回日本水環境学会シンポジウム, Sep. 2018, [Domestic conference]
• バイオマス燃焼が与える粒径別大気エアロゾル成分への影響　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 熊谷貴美代, 三小田憲史
  第59回大気環境学会年会, Sep. 2018, [Domestic conference]
• 過酸化水素源として過炭酸ナトリウムを用いたAOPによるVOC分解に関する研究　　　　　　　　　　　　　　　
  泉 俊輝, 関口 和彦, 三小田憲史, 安井 文男
  第59回大気環境学会年会, Sep. 2018, [Domestic conference]
• 関東圏における粒径別大気エアロゾル成分の濃度変動　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 熊谷貴美代, 三小田憲史
  第59回大気環境学会年会, Sep. 2018, [Domestic conference]
• ベトナムハノイにおける発生源の異なる大気浮遊粒子の粒径別性状評価　　　　　　　　　　　　　　　
  今野 創太, 黒土 優太, 関口 和彦, 三小田憲史, 松見 豊, 熊谷貴美代, 藤野 毅, 藤谷 雄二, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第59回大気環境学会年会, Sep. 2018, [Domestic conference]
• ベトナム・ハノイ都市部ならびに郊外における小型PM2.5計による長期多点計測：PM2.5濃度変動に与える季節ならびに観測地点の影響　　　　　　　　　　　　　　　
  松見 豊, 山崎 高幸, 岡本 渉, 中山 智喜, 関口 和彦, 藤野 毅, 三小田憲史, 熊谷貴美代, 藤谷 雄二, Nghiem Trung Dung, Ly Bich Thuy, Nguyen Thi Thu Thuy, Pham Chau Thuy
  第59回大気環境学会年会, Sep. 2018, [Domestic conference]
• Development of accurate low-cost PM2.5 instruments and measurements in Asian countries　　　　　　　　　　　　　　　
  Y. Matsumi, T. Nakayama, T. Yamasaki, W. Okamoto, S. Hayashida, K. Sekiguchi, S. Dhaka, D. Nghiem, B.-T. Ly, S. Chonokhuu
  Abstracts of the 15th International Global Atmospheric Chemistry (IGAC) Science Conference, Sep. 2018, [International conference]
• Effective decomposition of organic pollutants in water by the combined use of ultrasonication and UV irradiation　　　　　　　　　　　　　　　
  K. Sekiguchi, Y. Ono, K. Sankoda
  Proceedings of the 25th International Symposium on Contamination Control, Sep. 2018, [International conference]
• Influence of experimental factors on trapping of gas phase pollutants into water by micro-bubbling with oil addition　　　　　　　　　　　　　　　
  K. Sekiguchi, T. Nishitani, K. Sankoda, F. Yasui
  Proceedings of the 25th International Symposium on Contamination Control, Sep. 2018, [International conference]
• Study on decomposition of organic substances in liquid phase using immobilized photocatalyst and ozone microbubbles　　　　　　　　　　　　　　　
  F. Yasui, K. Sekiguchi, H. Tamura
  Proceedings of the 25th International Symposium on Contamination Control, Sep. 2018, [International conference]
• 超音波霧化粗大液滴を利用した浮遊超微粒子の分離捕集　　　　　　　　　　　　　　　
  並木 則和, 西下 仁人, 中山 良一, 関口 和彦, 二井 晋
  化学工学会 第50回秋季大会, Sep. 2018, [Domestic conference]
• 超音波霧化濃縮における蒸発の影響　　　　　　　　　　　　　　　
  野島 詩織, 水田 敬, 五島 崇, 関口 和彦, 並木 則和, 松浦 一雄, 二井 晋
  化学工学会 第50回秋季大会, Sep. 2018, [Domestic conference]
• 関東圏における大気粒子へのバイオマス燃焼由来成分の粒径別寄与　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 熊谷貴美代, 三小田憲史
  第35回エアロゾル科学・技術研究討論会, Aug. 2018, [Domestic conference]
• 超音波ミスト表面でのAOP手法を用いた気液相中有機汚染物質の分解　　　　　　　　　　　　　　　
  関口 和彦, 小野 雄誠, 三小田憲史, 並木 則和, 二井 晋
  第35回エアロゾル科学・技術研究討論会, Aug. 2018, [Domestic conference]
• Distribution and deposition mass variation of PAHs in precipitation　　　　　　　　　　　　　　　
  S. Ishikawa, K. Sankoda, K. Sekiguchi, Q. Wang
  Abstracts of the Water and Environment Technology Conference (WET) 2018, Jul. 2018, [International conference]
• Secondary formation of halogenated polycyclic aromatic hydrocarbons by photochemical reaction on mineral particle　　　　　　　　　　　　　　　
  H. Moroi, K. Sankoda, K. Sekiguchi, Q. Wang
  Abstracts of the Water and Environment Technology Conference (WET) 2018, Jul. 2018, [International conference]
• Characteristics, occurrence and photoreactivity of dissolved organic matter in an effluent dominating urban river　　　　　　　　　　　　　　　
  C. Yamamoto, K. Sankoda, K. Sekiguchi, Q. Wang
  Abstracts of the Water and Environment Technology Conference (WET) 2018, Jul. 2018, [International conference]
• 超音波霧化粗大液滴を利用した浮遊超微粒子の捕集　　　　　　　　　　　　　　　
  並木 則和, 西下 仁人, 中山 良一, 関口 和彦, 二井 晋
  第35回エアロゾル科学・技術研究討論会, Jul. 2018, [Domestic conference]
• 多孔質テフロンチューブと超音波ミストを用いた有機汚染ガス処理手法の検討　　　　　　　　　　　　　　　
  関口 和彦, 竹村 草太, 三小田憲史
  第35回エアロゾル科学・技術研究討論会, Jul. 2018, [Domestic conference]
• 同時観測キャンペーンに基づく東アジア都市域のPM0.1特性　　　　　　　　　　　　　　　
  S. Hongtieab, P. Sok, 畑 光彦, 古内 正美, M. Amin, N. Kumsanlas, P. Saleephum, 関口 和彦, 他30名
  第35回エアロゾル科学・技術研究討論会, Jul. 2018, [Domestic conference]
• ベトナムハノイにおける大気浮遊粒子の粒径別性状評価　　　　　　　　　　　　　　　
  今野 創太, 黒土 優太, 関口 和彦, 三小田憲史, 藤野 毅, 松見 豊, 熊谷貴美代, 藤谷雄二
  第35回エアロゾル科学・技術研究討論会, Jul. 2018, [Domestic conference]
• スモッグチャンバーを用いた屋内外環境条件におけるSOA生成に関する研究　　　　　　　　　　　　　　　
  中村駿太朗, 関口 和彦, 三小田憲史, 小前 草太
  第35回エアロゾル科学・技術研究討論会, Jul. 2018, [Domestic conference]
• 酸化チタンを含有した超音波霧化液滴を用いた揮発性有機化合物(VOC)の光触媒分解性能の向上　　　　　　　　　　　　　　　
  木村 美結, 中山 良一, 並木 則和, 関口 和彦, 鍵 直樹
  第35回エアロゾル科学・技術研究討論会, Jul. 2018, [Domestic conference]
• 消毒副生成物前駆体となる溶存有機物の都市河川における動態　　　　　　　　　　　　　　　
  山本千恵子, 三小田憲史, 関口 和彦, 王 青躍
  第27回環境化学討論会, May 2018, [Domestic conference]
• 下水処理水中におけるPPCPsの直接・間接光分解性の評価　　　　　　　　　　　　　　　
  三小田憲史, 會田 拓也, 菅原 悠太, 関口 和彦, 王 青躍
  第27回環境化学討論会, May 2018, [Domestic conference]
• ベトナム・ハノイにおける小型計測器によるPM2.5の長期・多点測定　　　　　　　　　　　　　　　
  岡本 渉, 松見 豊, 関口 和彦, 藤野 毅, 三小田憲史, 熊谷貴美代, 藤谷 雄二, L. B. Thuy, N. T. Dung, N. T. T. Thuy, P. C. Thuy, 梶井 克純, 坂本 陽介
  日本地球惑星科学連合2018年大会, May 2018, [Domestic conference]
• 光化学反応によるハロゲン化PAHs生成に対する土壌金属の影響　　　　　　　　　　　　　　　
  諸井 響, 三小田憲史, 関口 和彦
  第27回環境化学討論会, May 2018, [Domestic conference]
• 降雨によるPAHsのノンポイント汚染負荷量に関する調査　　　　　　　　　　　　　　　
  石川 冴夏, 三小田憲史, 関口 和彦, 王 青躍
  第27回環境化学討論会, May 2018, [Domestic conference]
• 消毒副生成物前駆体となる溶存有機物の都市河川における動態　　　　　　　　　　　　　　　
  山本千恵子, 三小田憲史, 関口 和彦, 王 青躍
  第27回環境化学討論会, May 2018, [Domestic conference]
• 酸化チタン含有超音波霧化液滴を用いた揮発性有機化合物（VOC）の光触媒分解の向上　　　　　　　　　　　　　　　
  木村 美結, 中山 良一, 並木 則和, 関口 和彦, 鍵 直樹
  第35回空気清浄とコンタミネーションコントロール研究大会, Apr. 2018, [Domestic conference]
• ガス状汚染物質のマイクロバブリング液相捕捉における諸因子の影響　　　　　　　　　　　　　　　
  関口 和彦, 西谷 俊秀, 三小田憲史, 安井 文男
  第35回空気清浄とコンタミネーションコントロール研究大会, Apr. 2018, [Domestic conference]
• 超音波とUV照射の併用による有機汚染物質の二相分解　　　　　　　　　　　　　　　
  関口 和彦, 小野 雄誠, 三小田憲史, 並木 則和, 二井 晋
  第35回空気清浄とコンタミネーションコントロール研究大会, Apr. 2018, [Domestic conference]
• 可視光応答型光触媒を用いた水中VOCの超音波光触媒分解　　　　　　　　　　　　　　　
  関口 和彦, 高橋 佑佳, 三小田憲史
  第35回空気清浄とコンタミネーションコントロール研究大会, Apr. 2018, [Domestic conference]
• 超音波霧化液滴を用いた浮遊超微粒子の捕集　　　　　　　　　　　　　　　
  並木 則和, 西下 仁人, 中山 良一, 関口 和彦, 二井 晋
  第35回空気清浄とコンタミネーションコントロール研究大会, Apr. 2018, [Domestic conference]
• 過炭酸ナトリウムを用いた低湿度条件下での過酸化水素ガス発生手法の検討　　　　　　　　　　　　　　　
  関口 和彦, 千田 浩大, 三小田憲史, 安井 文男
  第35回空気清浄とコンタミネーションコントロール研究大会, Apr. 2018, [Domestic conference]
• 家庭用品由来VOC からの室内二次有機エアロゾル（ISOA）生成への既存粒子の影響　　　　　　　　　　　　　　　
  古屋 郁美, 中山 良一, 並木 則和, 鍵 直樹, 関口 和彦
  第35回空気清浄とコンタミネーションコントロール研究大会, Apr. 2018, [Domestic conference]
• マイクロバブリングを用いた気相汚染物質の液中捕捉に関する検討　　　　　　　　　　　　　　　
  関口 和彦
  第7回科学の甲子園全国大会, Mar. 2018, [Invited], [Domestic conference]
• 小空間を対象とした超音波ミスト表面でのVOCガスの促進酸化分解と無機化　　　　　　　　　　　　　　　
  関口 和彦
  第7回科学の甲子園全国大会, Mar. 2018, [Invited], [Domestic conference]
• 超音波照射下における界面反応を用いた有機汚染物質の高効率分解　　　　　　　　　　　　　　　
  関口 和彦
  第7回科学の甲子園全国大会, Mar. 2018, [Invited], [Domestic conference]
• 可視光応答型光触媒を用いた水中VOCの超音波光触媒分解　　　　　　　　　　　　　　　
  高橋 佑佳, 関口 和彦, 三小田憲史
  第52回水環境学会年会, Mar. 2018, [Domestic conference]
• 下水処理水に含まれる溶存有機物のキャラクタリゼーションと動態解析　　　　　　　　　　　　　　　
  三小田憲史, 山本千恵子, 関口 和彦
  第52回水環境学会年会, Mar. 2018, [Domestic conference]
• 河川水を用いたPPCPsの収着挙動に関する研究　　　　　　　　　　　　　　　
  菅原 悠太, 三小田憲史, 関口 和彦, 王 青躍
  第52回水環境学会年会, Mar. 2018, [Domestic conference]
• EEM-PARAFAC を用いた河川流下における人為起源有機物の変質過程解析　　　　　　　　　　　　　　　
  山本千恵子, 三小田憲史, 関口 和彦
  日本腐植物質学会第33回講演会, Nov. 2017, [Domestic conference]
• 超音波と短波長紫外光を併用した水中アルデヒド類の二相分解　　　　　　　　　　　　　　　
  小野 雄誠,関口 和彦, 三小田憲史
  第26回ソノケミストリー討論会, Oct. 2017, [Domestic conference]
• 超音波光触媒反応における光触媒種の影響　　　　　　　　　　　　　　　
  高橋 佑佳,関口 和彦, 三小田憲史
  第26回ソノケミストリー討論会, Oct. 2017, [Domestic conference]
• 慣性フィルターサンプラーを用いた粒径別発生源指標の調査　　　　　　　　　　　　　　　
  黒土 優太, 関口 和彦, 三小田憲史, 熊谷貴美代
  第58回大気環境学会年会, Sep. 2017, [Domestic conference]
• 小空間を対象とした超音波ミスト表面でのVOC ガスの促進酸化分解と無機化　　　　　　　　　　　　　　　
  関口 和彦, 楢原 壮馬, 小野 雄誠, 三小田憲史, 並木 則和, 二井 晋
  第58回大気環境学会年会, Sep. 2017, [Domestic conference]
• 関東の都市、郊外、森林地点におけるPM2.5 中の二次有機成分の挙動　　　　　　　　　　　　　　　
  熊谷貴美代, 田子 博, 齊藤 由倫, 飯島 明宏, 工藤 慎治, 関口 和彦
  第58回大気環境学会年会, Sep. 2017, [Domestic conference]
• 超音波ミストの界面反応を用いたアルデヒドの分解促進　　　　　　　　　　　　　　　
  関口 和彦, 小野 雄誠, 三小田憲史
  第34回エアロゾル科学・技術研究討論会, Aug. 2017, [Domestic conference]
• 酸化チタンを含む超音波霧化液滴を用いたVOCの光触媒分解　　　　　　　　　　　　　　　
  中山 良一, 鈴木さつき, 並木 則和, 関口 和彦, 二井 晋, 鍵 直樹, 諏訪 好英
  第34回エアロゾル科学・技術研究討論会, Aug. 2017, [Domestic conference]
• ベトナム、ハノイにおける粒子成長の特徴　　　　　　　　　　　　　　　
  山口 良介, 関口 和彦, 三小田憲史, 熊谷貴美代, 藤谷 雄二, Nghiem Trung Dung, Nguyen Thi Thu Thuy
  第34回エアロゾル科学・技術研究討論会, Aug. 2017, [Domestic conference]
• Aqueous nanodroplet generated by ultrasonic atomization　　　　　　　　　　　　　　　
  S. Nii, K. Sekiguchi
  Abstracts of the The 5th International Symposium & Exhibition on Aqua Science and Water Resources, Aug. 2017, [International conference]
• 関東地域の都市・郊外・森林地点におけるPM2.5中有機マーカー成分の特徴　　　　　　　　　　　　　　　
  熊谷貴美代, 田子 博, 齊藤 由倫, 工藤 慎治, 飯島 明宏, 関口 和彦
  第34回エアロゾル科学・技術研究討論会, Aug. 2017, [Domestic conference]
• 慣性サンプラーを用いた水溶性有機成分の粒径別評価　　　　　　　　　　　　　　　
  関口 和彦, 黒土 優太, 熊谷貴美代, 三小田憲史
  第34回エアロゾル科学・技術研究討論会, Aug. 2017, [Domestic conference]
• 超音波霧化により生成した負ナノ液滴の生成および制御　　　　　　　　　　　　　　　
  唐津 渉, 西下 仁人, 中山 良一, 並木 則和, 関口 和彦, 二井 晋
  第34回エアロゾル科学・技術研究討論会, Aug. 2017, [Domestic conference]
• 超音波ミストの粒径分布測定と空気浄化手法への応用　　　　　　　　　　　　　　　
  関口 和彦
  超音波霧化分離セミナー, Jul. 2017, [Invited], [Domestic conference]
• Characterization and trasnsformation of dissolved organic matter in an effluent-impacted urban river　　　　　　　　　　　　　　　
  C. Yamamoto, K. Sankoda, K. Sekiguchi
  Abstracts of Water and Environment Technology Conference 2017, Jul. 2017, [International conference]
• Photocatalytic degradation of VOCs using TiO2-containing droplets atomized by ultrasonic irradiation　　　　　　　　　　　　　　　
  N. Namiki, S. Suzuki, R. Nakayama, K. Sekiguchi, S. Nii, N. Kagi, Y. Suwa
  Abstracts of the 10th Asian Aerosol Conference 2017, Jul. 2017, [International conference]
• Degradation and mineralization of VOC gas on ultrasonic mist using advanced oxidation processes　　　　　　　　　　　　　　　
  K. Sekiguchi, S. Narahara, K. Sankoda, N. Namiki, S. Nii
  Abstracts of the 10th Asian Aerosol Conference 2017, Jul. 2017, [International conference]
• Characteristics of N-nitrosamines in atmospheric PM2.5 and PM0.1 at roadside environment　　　　　　　　　　　　　　　
  K. H. Kim, Y. M. Hong, H. J. Ok, M. H. Lee, M. Kinoshita, S. Kudo, K. Sakamoto, K. Sekiguchi
  Abstracts of the 10th Asian Aerosol Conference 2017, Jul. 2017, [International conference]
• Identification of PM2.5 sources in Japan using organic and inorganic markers by positive matrix factorization　　　　　　　　　　　　　　　
  A. Iijima, S. Kudo, K. Kumagai, H. Tago, Y. Saitoh, S. Kimura, K. Sekiguchi
  Abstracts of the 10th Asian Aerosol Conference 2017, Jul. 2017, [International conference]
• Characteristic evaluation of chemical components in PM0.1-2.5 and PM0.1 collected in Chiang Mai, Thailand during biomass burning season　　　　　　　　　　　　　　　
  T. Chetiyanukornkul, R. Janta, R. Yamaguchi, K. Sekiguchi, K. Sankoda, K. Kumagai, Y. Fujitani
  Abstracts of the 10th Asian Aerosol Conference 2017, Jul. 2017, [International conference]
• Detailed analysis of water-soluble organic components in size-segregated particles collected at a suburban site in Saitama, Japan using an inertial filter sampler　　　　　　　　　　　　　　　
  Y. Kurotsuchi, K. Sekiguchi, K. Sankoda
  Abstracts of the 10th Asian Aerosol Conference 2017, Jul. 2017, [International conference]
• Improvement of degradation performance for organic pollutants in water using ultrasonic atomization and reaction on mist surface　　　　　　　　　　　　　　　
  Y. Ono, K. Sekiguchi, K. Sankoda
  Abstracts of the 10th Asian Aerosol Conference 2017, Jul. 2017, [International conference]
• 国内都市部における降雨による大気中PAHsの洗浄作用の評価　　　　　　　　　　　　　　　
  石川 冴夏, 三小田憲史, 関口 和彦
  第26回環境化学討論会, Jun. 2017, [Domestic conference]
• 干潟環境下におけるPAHsの光化学分解とハロゲン化誘導体精製に対する溶存有機物の影響　　　　　　　　　　　　　　　
  諸井 響, 三小田憲史, 関口 和彦
  第26回環境化学討論会, Jun. 2017, [Domestic conference]
• 半導体の微細化に潜んでいる新たなDefect誘発要因　　　　　　　　　　　　　　　
  白水 好美, 関口 和彦
  第34回空気清浄とコンタミネーションコントロール研究大会, Apr. 2017, [Domestic conference]
• 家庭用品由来二成分系VOCからの室内二次有機エアロゾル(ISOA)の生成　　　　　　　　　　　　　　　
  古屋 郁美, 中山 良一, 並木 則和, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  第34回空気清浄とコンタミネーションコントロール研究大会, Apr. 2017, [Domestic conference]
• 超音波霧化液滴中のTiO2粒子を用いたVOCの光触媒分解　　　　　　　　　　　　　　　
  中山 良一, 鈴木さつき, 並木 則和, 関口 和彦, 二井 晋, 鍵 直樹, 諏訪 好英
  第34回空気清浄とコンタミネーションコントロール研究大会, Apr. 2017, [Domestic conference]
• 気相汚染物質のマイクロバブリング液相捕捉における油種およびガス種の影響　　　　　　　　　　　　　　　
  関口 和彦, 西谷 俊秀, 三小田憲史, 安井 文男, 佐藤 朋且, 藤井 美紗
  第34回空気清浄とコンタミネーションコントロール研究大会, Apr. 2017, [Domestic conference]
• 超音波とUV照射の併用による有機汚染物質の分解率評価　　　　　　　　　　　　　　　
  関口 和彦, 小野 雄誠, 三小田憲史
  第34回空気清浄とコンタミネーションコントロール研究大会, Apr. 2017, [Domestic conference]
• 誘導荷電による超音波霧化微小液滴の単極化の試み　　　　　　　　　　　　　　　
  唐津 渉, 西下 仁人, 中山 良一, 並木 則和, 関口 和彦, 二井 晋
  第34回空気清浄とコンタミネーションコントロール研究大会, Apr. 2017, [Domestic conference]
• 超音波霧化による生成液滴を用いた超微粒子の除去　　　　　　　　　　　　　　　
  西下 仁人, 中山 良一, 並木 則和, 関口 和彦, 二井 晋
  第34回空気清浄とコンタミネーションコントロール研究大会, Apr. 2017, [Domestic conference]
• 水環境中における多環芳香族炭化水素の光化学反応機構と共存物質の影響　　　　　　　　　　　　　　　
  三小田憲史, 諸井 響, 関口 和彦, 篠原 亮太
  第51回水環境学会年会, Mar. 2017, [Domestic conference]
• 超音波ミストの粒径分布測定と空気浄化手法への応用　　　　　　　　　　　　　　　
  関口 和彦
  超音波霧化分離セミナー, Mar. 2017, [Invited], [Domestic conference]
• ファインバブルの特性を生かした空気浄化手法への応用　　　　　　　　　　　　　　　
  関口 和彦
  第8回ファインバブル技術講習会, Mar. 2017, [Invited], [Domestic conference]
• 下水処理水が流れる都市河川における溶存有機物のキャラクタリゼーションと流下によるその変質　　　　　　　　　　　　　　　
  山本千恵子, 関口 和彦, 三小田憲史
  第51回水環境学会年会, Mar. 2017, [Domestic conference]
• 大気光化学反応の空気浄化手法への応用と促進酸化手法を併用した分解生成物の抑制　　　　　　　　　　　　　　　
  関口 和彦
  東京都環境計量協議会技術研修会, Jan. 2017, [Invited], [Domestic conference]
• 大気汚染とPM2.5の基礎　　　　　　　　　　　　　　　
  関口 和彦
  低炭素まちづくりフォーラム分科会「大気汚染とPM2.5を考える～PM2.5を正しく知ることで見えてくるもの～」, Dec. 2016, [Invited], [Domestic conference]
• 促進酸化手法を用いた超音波ミスト上でのVOCガスの分解と無機化　　　　　　　　　　　　　　　
  関口 和彦, 楢原 壮馬, 三小田憲史, 並木 則和, 二井 晋
  第25回ソノケミストリー討論会, Oct. 2016, [Domestic conference]
• 諸条件におけるUS/光触媒反応効率の評価　　　　　　　　　　　　　　　
  佐藤 洸太, 関口 和彦, 三小田憲史, 王 青躍
  第25回ソノケミストリー討論会, Oct. 2016, [Domestic conference]
• 超音波照射下での気液相反応を用いた有機汚染物質の分解率評価　　　　　　　　　　　　　　　
  小野 雄誠, 関口 和彦, 三小田憲史
  第25回ソノケミストリー討論会, Oct. 2016, [Domestic conference]
• 超音波霧化により発生させたナノサイズミスト径に与える周波数の影響　　　　　　　　　　　　　　　
  関口 和彦, 工藤 貴久, 三小田憲史, 並木 則和, 二井 晋
  第25回ソノケミストリー討論会, Oct. 2016, [Domestic conference]
• Application of short-wavelength UV light and ultrasonic atomization to photocatalytic air purification techniques　　　　　　　　　　　　　　　
  K. Sekiguchi, K. Sankoda
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Application of ultrasonication and short-wavelength UV irradiation to the degradation of persistent flurochemicals　　　　　　　　　　　　　　　
  K. Sekiguchi, Y. Ono, T. Kudo, K. Sankoda
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Photodegradation and phototransformation of micropollutants in aquatic system　　　　　　　　　　　　　　　
  K. Sankoda, J. Kobayashi, K. Sekiguchi
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Lab-scale evaluation of trapping performance for gas phase pollutants into water using microbubbles　　　　　　　　　　　　　　　
  K. Sekiguchi, T. Nishitani, E. Fujii, K. Sankoda, H. Yasui, T. Satou, M. Fujii
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Evaluation of gas adsorption onto a quartz fiber filter during sampling of ultrafine particles using an inertial filter sampler　　　　　　　　　　　　　　　
  K. Sekiguchi, Y. Kurotsuchi, H. Kuwabara, K. Sankoda
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Degradation and mineralization of voc gas on ultrasonic mist using AOP techniques　　　　　　　　　　　　　　　
  K. Sekiguchi, S. Narahara, K. Sankoda, N. Namiki, S. Nii
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Development of an analytical method for PAHs in the atmosphere and precipitation using CPP-GC/MS　　　　　　　　　　　　　　　
  S. Ishikawa, K. Oya, M. Kamiyama, K. Sankoda, K. Sekiguchi
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Effect of ultrasonic irradiation on solid acid catalytic saccharification of cellulose　　　　　　　　　　　　　　　
  T. Nonaka, K. Sekiguchi, K. Sankoda
  Abstracts of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• ベトナムハノイにおけるPM2.5およびPM0.1中化学成分の雨季乾での比較　　　　　　　　　　　　　　　
  山口 良介, 関口 和彦, 三小田憲史, 熊谷貴美代, 藤谷 雄二, Nguyen Thi Thu Thuy, Nghiem Trung Dung
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 二次有機エアロゾルの酸化・凝縮プロセスに与える金属核粒子の影響　　　　　　　　　　　　　　　
  濱 大祐, 関口 和彦, 三小田憲史
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• マイクロバブリングを用いた気相汚染物質の液中捕捉に関する検討　　　　　　　　　　　　　　　
  関口 和彦, 藤井 絵真, 三小田憲史, 安井 文男
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 屋内外オンライン計測による生活空間での微粒子発生の挙動の調査　　　　　　　　　　　　　　　
  小前 草太, 関口 和彦, 三小田憲史, 佐藤 光太
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• Application of short-wavelength UV light and ultrasonic atomization to photocatalytic air purification techniques　　　　　　　　　　　　　　　
  K. Sekiguchi
  Plenary Lecture at the International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [Invited], [International conference]
• 中国上海市郊外における夏・冬季の微小粒子中の37種類の多環芳香族炭化水素類の挙動　　　　　　　　　　　　　　　
  王 青躍, 小林 佳祐, 阮 潔, 呂 森林, 中島 大介, 柳下真由子, 関口 和彦, 米持 真一
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 都市部大気中微小粒子状物質の無機成分の粒径別組成と地域間の比較　　　　　　　　　　　　　　　
  王 青躍, 齋藤 友也, 阮 潔, 呂 森林, 米持 真一, 関口 和彦, 長江 真樹, 高尾 雄二
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 都市、郊外、森林地点におけるPM2.5同時観測－無機ガスとの関係　　　　　　　　　　　　　　　
  田子 博, 熊谷貴美代, 木村 真也, 齊藤 由倫, 飯島 明宏, 工藤 慎治, 関口 和彦
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 都市、郊外、森林地点におけるPM2.5同時観測－無機元素の特徴　　　　　　　　　　　　　　　
  齊藤 由倫, 熊谷貴美代,田子 博,木村 真也, 飯島 明宏, 工藤 慎治, 関口 和彦
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 有機マーカー成分を用いたPM2.5発生源寄与の推定(1)－PMFモデルによる発生源の割り当て　　　　　　　　　　　　　　　
  飯島 明宏, 工藤 慎治, 熊谷貴美代, 田子 博, 齊藤 由倫, 木村 真也, 関口 和彦
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 有機マーカー成分を用いたPM2.5発生源寄与の推定(2)－気象解析による発生地域の推定　　　　　　　　　　　　　　　
  工藤 慎治, 飯島 明宏, 熊谷貴美代, 田子 博, 齊藤 由倫, 木村 真也, 関口 和彦
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• 都市、郊外、森林地点におけるPM2.5同時観測－有機マーカ成分の挙動　　　　　　　　　　　　　　　
  熊谷貴美代, 田子 博, 齊藤 由倫, 木村 真也, 工藤 慎治, 飯島 明宏, 関口 和彦
  第57回大気環境学会年会, Sep. 2016, [Domestic conference]
• Seasonal variation of chemical components in PM2.5 and PM0.1 in Hanoi　　　　　　　　　　　　　　　
  R. Yamaguchi, K. Sekiguchi*, K. Sankoda, H. Kuwabara, K. Kumagai, Y. Fujitani, N. T. T. Thuy, N. T. Dung
  Procedings of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• Seasonal variation of concentrations and carbonaceous components of nanoparticles at a roadside location of Hanoi, Vietnam　　　　　　　　　　　　　　　
  N. T. T. Thuy, N. T. Dung, K. Sekiguchi, R. Yamaguchi, P. C. Thuy, D. T. Nam, H. Q. Bang, T. T. An
  Procedings of International Conference on Environmental Engineering and Management for Sustainable Development, Sep. 2016, [International conference]
• 超音波ミスト発生に与える周波数の影響　　　　　　　　　　　　　　　
  関口 和彦, 工藤 貴久, 三小田憲史, 並木 則和, 二井 晋
  第33回エアロゾル科学・技術研究討論会, Sep. 2016, [Domestic conference]
• 超音波霧化液滴とTiO2光触媒を用いたVOCの分解　　　　　　　　　　　　　　　
  鈴木さつき, 西下 仁人, 並木 則和, 関口 和彦, 二井 晋
  第33回エアロゾル科学・技術研究討論会, Sep. 2016, [Domestic conference]
• 超音波ミスト上における反応活性種とVOCガスとの反応性評価　　　　　　　　　　　　　　　
  関口 和彦, 楢原 壮馬, 並木 則和, 藤井 修二, 垂水 弘夫, 鍵 直樹, 諏訪 好英, 田村 一, 東 賢一
  第33回エアロゾル科学・技術研究討論会, Sep. 2016, [Domestic conference]
• 家庭用品由来VOCからの室内二次有機エアロゾル(ISOA)粒子生成とその変質　　　　　　　　　　　　　　　
  並木 則和, 鈴木 恵, 鍵 直樹, 藤井 修二, 垂水 弘夫, 関口 和彦, 東 賢一, 諏訪 好英, 田村 一
  第33回エアロゾル科学・技術研究討論会, Sep. 2016, [Domestic conference]
• ISOA生成プロセスのモデリングとコンピュータシミュレーション　　　　　　　　　　　　　　　
  諏訪 好英, 松久 裕司, 並木 則和, 鍵 直樹, 藤井 修二, 垂水 弘夫, 関口 和彦, 東 賢一, 田村 一
  第33回エアロゾル科学・技術研究討論会, Sep. 2016, [Domestic conference]
• ベトナムハノイにおけるPM2.5およびPM0.1中化学成分の特性評価　　　　　　　　　　　　　　　
  山口 良介, 関口 和彦, 三小田憲史, 熊谷貴美代, 藤谷 雄二, Nguyen Thi Thu Thuy, Nghiem Trung Dung
  第33回エアロゾル科学・技術研究討論会, Sep. 2016, [Domestic conference]
• 二次有機エアロゾル生成プロセスに与える金属核粒子の影響　　　　　　　　　　　　　　　
  濱 大祐, 関口 和彦, 三小田憲史
  第33回エアロゾル科学・技術研究討論会, Sep. 2016, [Domestic conference]
• マイクロバブルを用いた水／油バブルカラムによるVOCガスの液相捕捉に関する研究　　　　　　　　　　　　　　　
  安井 文男, 佐藤 朋且, 藤井 美紗, 関口 和彦, 藤井 絵真, 三小田憲史
  日本混相流学会混相流シンポジウム2016, Aug. 2016, [Domestic conference]
• ベトナムハノイと日本関東地域における大気エアロゾル中有機成分の特徴　　　　　　　　　　　　　　　
  熊谷貴美代, 関口 和彦, 山口 良介, 藤谷 雄二, Nguyen Thi Thu Thuy, Nghiem Trung Dung
  第33回エアロゾル科学・技術研究討論会, Aug. 2016, [Domestic conference]
• 超音波霧化液滴を用いた超微粒子捕集　　　　　　　　　　　　　　　
  西下 仁人, 並木 則和, 鈴木さつき, 関口 和彦, 二井 晋
  第33回エアロゾル科学・技術研究討論会, Aug. 2016, [Domestic conference]
• 東アジア都市域における大気中ナノ粒子特性の考察　　　　　　　　　　　　　　　
  趙 天任, ホンティアブ スラパー, 畑 光彦, 松木 篤, 古内 正美, 関口 和彦, 吉川 文恵, 池盛 文数, 西村 理恵, テカサクル ペラポン, ホァ シゥメイ, バン クォック ホー, クナイフィ
  第33回エアロゾル科学・技術研究討論会, Aug. 2016, [Domestic conference]
• Influence of metal particles on formation process of secondary organic aerosols　　　　　　　　　　　　　　　
  D. Hama, K. Sekiguchi, Q. Wang
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2016, [International conference]
• 超音波霧化を用いた粒子およびVOC同時除去システムの構築－超音波霧化液滴を用いたVOCの分解－　　　　　　　　　　　　　　　
  鈴木さつき, 西下 仁人, 並木 則和, 関口 和彦, 二井 晋
  第33回空気清浄とコンタミネーションコントロール研究大会, Apr. 2016, [Domestic conference]
• 超音波霧化液滴を用いた粒子捕集装置の構築　　　　　　　　　　　　　　　
  西下 仁人, 並木 則和, 鈴木さつき, 関口 和彦, 二井 晋
  第33回空気清浄とコンタミネーションコントロール研究大会, Apr. 2016, [Domestic conference]
• マイクロバブルを用いた水／油バブルカラムによる気相汚染物質の液相捕捉に関する研究　　　　　　　　　　　　　　　
  関口 和彦, 藤井 絵真, 三小田憲史, 安井 文男, 佐藤 朋且, 藤井 美紗
  第33回空気清浄とコンタミネーションコントロール研究大会, Apr. 2016, [Domestic conference]
• 二次有機エアロゾルの生成プロセスに与える金属核粒子の影響に関する研究　　　　　　　　　　　　　　　
  関口 和彦, 濱 大祐,三小田憲史
  第33回空気清浄とコンタミネーションコントロール研究大会, Apr. 2016, [Domestic conference]
• αピネン、d-リモネンとオゾンの反応による二次有機エアロゾル形成　　　　　　　　　　　　　　　
  原田 隼彰, 鍵 直樹, 新井 美央, 並木 則和, 諏訪 好英, 関口 和彦, 東 賢一, 田村 一, 垂水 弘夫, 藤井 修二
  第33回空気清浄とコンタミネーションコントロール研究大会, Apr. 2016, [Domestic conference]
• 促進酸化手法を用いた超音波ミスト上でのトルエンガスの分解と無機化　　　　　　　　　　　　　　　
  関口 和彦, 楢原 壮馬, 並木 則和, 藤井 修二, 鍵 直樹, 東 賢一, 諏訪 好英, 田村 一
  第33回空気清浄とコンタミネーションコントロール研究大会, Apr. 2016, [Domestic conference]
• 家庭用品由来VOC からの室内二次有機エアロゾル(ISOA)粒子生成と変質過程の解明　　　　　　　　　　　　　　　
  中山 良一, 並木 則和, 鈴木 恵, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  第33回空気清浄とコンタミネーションコントロール研究大会, Apr. 2016, [Domestic conference]
• ①エアロゾル質量分析計を用いた屋内外移流挙動の把握, ②促進酸化手法を用いた超音波ミストの活性化とVOCガス分解への応用　　　　　　　　　　　　　　　
  関口 和彦
  日本たばこ産業たばこ中央研究所講演会, Feb. 2016, [Invited], [Domestic conference]
• 家庭用品由来VOCからの室内二次有機エアロゾル(ISOA)粒子生成と変質過程　　　　　　　　　　　　　　　
  鈴木 恵, 並木 則和, 鍵 直樹, 藤井 修二, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  平成27年室内環境学会学術大会, Dec. 2015, [Domestic conference]
• 室内におけるオゾンとリモネンの粒子生成機構の解析　　　　　　　　　　　　　　　
  新井 美央, 鍵 直樹, 藤井 修二, 並木 則和, 諏訪 好英, 関口 和彦, 東 賢一, 田村 一
  平成27年室内環境学会学術大会, Dec. 2015, [Domestic conference]
• 家庭用品由来VOCからの室内二次有機エアロゾル（ISOA）粒子生成に及ぼす水分および既存粒子の影響　　　　　　　　　　　　　　　
  西村 美希, 鈴木さつき, 並木 則和, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  平成27年室内環境学会学術大会, Dec. 2015, [Domestic conference]
• 超音波霧化を用いた粒子およびVOC同時除去システムの構築に関する基礎的研究　　　　　　　　　　　　　　　
  鈴木さつき, 西下 仁人, 並木 則和, 関口 和彦, 二井 晋
  平成27年室内環境学会学術大会, Dec. 2015, [Domestic conference]
• 促進酸化手法を用いた超音波ミストの活性化とVOCガス分解への応用　　　　　　　　　　　　　　　
  関口 和彦
  化学工学会反応工学部会ソノプロセス分科会2015年度見学会・講演会, Oct. 2015, [Invited], [Domestic conference]
• 短波長紫外光を併用した過フッ化化合物の超音波分解　　　　　　　　　　　　　　　
  工藤 貴久, 関口 和彦, 三小田憲史, 王 青躍
  第24回ソノケミストリー討論会, Oct. 2015, [Domestic conference]
• 促進酸化法を用いた超音波ミストによるトルエンガスの分解　　　　　　　　　　　　　　　
  楢原 壮馬, 関口 和彦, 三小田憲史, 王 青躍
  第24回ソノケミストリー討論会, Oct. 2015, [Domestic conference]
• 暗条件・超音波照射下における光触媒活性の発現に関する研究　　　　　　　　　　　　　　　
  佐藤 洸太, 関口 和彦, 三小田憲史, 王 青躍
  第25回ソノケミストリー討論会, Oct. 2015, [Domestic conference]
• Study on mechanical filtration through tobacco columns: the effects of cut filter shape and size distribution　　　　　　　　　　　　　　　
  N. Ishikawa, K. Sekiguchi
  Abstracts of the CORESTA Smoke science and product technology meeting (SSPT) 2015, Oct. 2015, [International conference]
• 海水成分存在下における多環芳香族炭化水素の光化学反応過程とその生成物　　　　　　　　　　　　　　　
  三小田憲史, 栗林 知徳, 米原 敬之, 関口 和彦, 野見山 桂, 篠原 亮太
  第62回日本地球化学会年会, Sep. 2015, [Invited], [Domestic conference]
• 大気中超微小粒子および微小粒子に含まれる炭素成分および金属成分の季節変動　　　　　　　　　　　　　　　
  桑原 博俊, 関口 和彦, 三小田憲史, 王 青躍
  第56回大気環境学会年会, Sep. 2015, [Domestic conference]
• 異なる時間分解能でのPMF 解析を用いたPM1中化学成分の大気挙動比較　　　　　　　　　　　　　　　
  山口 良介, 関口 和彦, 三小田憲史, 王 青躍
  第56回大気環境学会年会, Sep. 2015, [Domestic conference]
• マイクロバブル手法を用いた気相汚染物質の高効率捕捉に関する研究　　　　　　　　　　　　　　　
  関口 和彦, 藤井 絵真, 三小田憲史, 王 青躍, 安井 文男, 佐藤 朋且
  日本混相流学会混相流シンポジウム2015, Aug. 2015, [Domestic conference]
• 多環芳香族炭化水素の水相における光ハロゲン化メカニズム　　　　　　　　　　　　　　　
  三小田憲史, Paul R Erickson, 関口 和彦, 篠原 亮太, Kristopher McNeill
  第24回環境化学討論会, Jun. 2015, [Domestic conference]
• Electrostatic collection of ultrafine particles by ultrasonic atomization　　　　　　　　　　　　　　　
  N Namiki, K. Sekiguchi, S. Nii
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Modeling and computer simulation on the formation process of ISOA　　　　　　　　　　　　　　　
  Y. Suwa, Y. Matsuhisa, S. Fuji, N. Kagi, N. Namiki, M. Suzuki, K. Sekiguchi, K. Azuma, H. Tamura
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Evaluation of atmospheric behavior of chemical components in PM1 using PMF analysis with different time resolutions　　　　　　　　　　　　　　　
  R. Yamaguchi, K. Sekiguchi, Q. Wang
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Seasonal and spatial variation of metal components in PM0.1 and PM2.5　　　　　　　　　　　　　　　
  H. Kuwabara, K. Sekiguchi, Q. Wang
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Size distributions of fine mist particles by changing in the ultrasonic frequency　　　　　　　　　　　　　　　
  T. Kudo, K. Sekiguchi, Q. Wang, N. Namiki, S. Nii
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Study on water scrubbing of gas phase pollutants using a microbubble technique　　　　　　　　　　　　　　　
  E. Fujii, K. Sekiguchi, Q. Wang
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Removal rate of ultrasonic mist and VOC gas under the conditions of various AOPs　　　　　　　　　　　　　　　
  S. Narahara, K. Sekiguchi, N. Namiki, S. Fujii, N. Kagi, Y. Suwa, K. Azuma, H. Tamura
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Ambient nanoparticles characterization by East Asia Nanoparticle Monitoring Network (EA-NANONET)　　　　　　　　　　　　　　　
  M. Hata, M. Furuuchi, S. Dong, W. Phairuang, H. Ge, T. Zhang, D. Onizuka, A. Matsuki, K. Kakimoto, N. Tang, A. Toriba, F. Hosokawa, K. Sekiguchi et al.
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Influence of airflow state on the formation process of ISOA　　　　　　　　　　　　　　　
  Y. Matsuhisa, Y. Suwa, S. Fujii, N. Kagi, N. Namiki, M. Suzuki, K. Sekiguchi, K. Azuma, H. Tamura
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• Characterizing evolution of indoor secondary organic nano-sized aerosols (ISOAs) formed from VOCs derived from house-keeping wares using a 2000-L gas bag　　　　　　　　　　　　　　　
  S. Suzuki, M. Suzuki, N. Namiki, S. Fujii, N. Kagi, K. Sekiguchi, K. Azuma, H. Tamura, Y. Suwa
  Abstracts of the 9th Asian Aerosol Conference 2015, Jun. 2015, [International conference]
• 促進酸化反応からみた超音波ミストとVOCガスの反応性評価　　　　　　　　　　　　　　　
  関口 和彦, 楢原 壮馬, 並木 則和, 東 賢一, 田村 一, 諏訪 好英, 鍵 直樹, 藤井 修二, 志村 哲也
  第32回空気清浄とコンタミネーションコントロール研究大会, Apr. 2015, [Domestic conference]
• マイクロバブル手法を用いた水スクラバー法による気相汚染物質の捕捉に関する研究　　　　　　　　　　　　　　　
  関口 和彦, 藤井 絵真, 王 青躍
  第32回空気清浄とコンタミネーションコントロール研究大会, Apr. 2015, [Domestic conference]
• 超音波と短波長紫外光を用いた過フッ化化合物の分解処理　　　　　　　　　　　　　　　
  関口 和彦, 工藤 貴久, 王 青躍
  第32回空気清浄とコンタミネーションコントロール研究大会, Apr. 2015, [Domestic conference]
• 異なる反応器を用いた家庭用品由来VOC からの室内二次有機エアロゾル（ISOA）生成　　　　　　　　　　　　　　　
  鈴木 恵, 並木 則和, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  第32回空気清浄とコンタミネーションコントロール研究大会, Apr. 2015, [Domestic conference]
• 家庭用品由来VOC からの室内二次有機エアロゾル（ISOA）生成とその成分分析　　　　　　　　　　　　　　　
  鈴木さつき, 鈴木 恵, 並木 則和, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  第32回空気清浄とコンタミネーションコントロール研究大会, Apr. 2015, [Domestic conference]
• ISOA生成機構のモデル化に関する研究－反応への気流影響と分子のクラスタ化に関する考察－　　　　　　　　　　　　　　　
  松久 裕司, 諏訪 好英, 並木 則和, 鈴木 恵, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一
  第32回空気清浄とコンタミネーションコントロール研究大会, Apr. 2015, [Domestic conference]
• 室内におけるオゾンとリモネンによる生成粒子の解析　　　　　　　　　　　　　　　
  新井 美央, 鍵 直樹, 藤井 修二, 並木 則和, 諏訪 好英, 関口 和彦, 東 賢一, 田村 一
  第32回空気清浄とコンタミネーションコントロール研究大会, Apr. 2015, [Domestic conference]
• 超音波霧化法による固体超微粒子の生成と静電除去　　　　　　　　　　　　　　　
  並木 則和, 関口 和彦
  化学工学会 第80年会, Mar. 2015, [Domestic conference]
• 室内空間中の水分と二次粒子生成　　　　　　　　　　　　　　　
  新井美央, 鍵 直樹, 山根由依子, 藤井 修二, 並木 則和, 関口 和彦, 東 賢一, 諏訪 好英, 田村 一
  平成26年室内環境学会学術大会, Dec. 2014, [Domestic conference]
• 家庭用品由来VOC から生成される室内二次有機エアロゾル(ISOA)の変質過程の解明　　　　　　　　　　　　　　　
  鈴木さつき, 鈴木 恵, 並木 則和, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  平成26年室内環境学会学術大会, Dec. 2014, [Domestic conference]
• 超音波と短波長紫外光を用いた難分解性有機フッ素化合物の分解処理　　　　　　　　　　　　　　　
  工藤 貴久, 関口 和彦, 王 青躍
  第23回ソノケミストリー討論会, Nov. 2014, [Domestic conference]
• 希硫酸を用いたセルロース系バイオマスの加水分解における超音波照射と物理的前処理の効果　　　　　　　　　　　　　　　
  関口 和彦, 馬場 航哉, 王 青躍
  第23回ソノケミストリー討論会, Nov. 2014, [Domestic conference]
• 超音波/固体酸法を用いたセルロース糖化における諸因子の影響　　　　　　　　　　　　　　　
  野中 匠, 関口 和彦, 王 青躍
  第23回ソノケミストリー討論会, Nov. 2014, [Domestic conference]
• Evaluation of surface reactivity for VOC gas and ozone on different ozone decomposition catalysts　　　　　　　　　　　　　　　
  K. Sekiguchi, K. Hayano, Q. Wang, F. Yasui, H. Tamura
  Proceedings of the 23rd International Symposium on Contamination Control, Oct. 2014, [International conference]
• Evaluation of chemical reactivity for VOC gas on the ultrasonic mist and the influence of frequency on mist generation　　　　　　　　　　　　　　　
  K. Sekiguchi, T. Kudo, T. Namiki, N. Namiki, K. Azuma, H. Tamura, Y. Suwa, N. Kagi, S. Fujii, T. Shimura
  Proceedings of the 23rd International Symposium on Contamination Control, Oct. 2014, [International conference]
• Formation of indoor nano-sized secondary organic aerosols (ISOAs) in a model residential room and measurements of their OC, EC and WSOC　　　　　　　　　　　　　　　
  M. Suzuki, N. Namiki, N. Kagi, S. Fujii, K. Sekiguchi
  Proceedings of the 23rd International Symposium on Contamination Control, Oct. 2014, [International conference]
• Modeling and computer simulation on the formation process from VOCs to ISOAs (Indoor Secondary Organic Aerosols)　　　　　　　　　　　　　　　
  Y. Suwa, S. Fujii, N. Kagi, Suzuki, N. Namiki, K. Sekiguchi, K. Azuma, H. Tamura
  Proceedings of the 23rd International Symposium on Contamination Control, Oct. 2014, [International conference]
• Development of an effective trap and removal technique for gas phase pollutants by transforming into water with microbubbles　　　　　　　　　　　　　　　
  K. Sekiguchi, E. Fujii, Q. Wang
  Proceedings of the 23rd International Symposium on Contamination Control, Oct. 2014, [International conference]
• 簡易個人エアサンプラーによる花粉飛散量調査手法の検討　　　　　　　　　　　　　　　
  王 青躍, 大塚 岳, 董 詩洋, 高井 優子, 関口 和彦
  日本花粉学会第55回大会, Sep. 2014, [Domestic conference]
• さいたま市都市部大気中のヒノキ花粉アレルゲン挙動調査　　　　　　　　　　　　　　　
  王 青躍, 高井 優子, 董 詩洋, 大塚 岳, 関口 和彦
  日本花粉学会第55回大会, Sep. 2014, [Domestic conference]
• 日本におけるスギ花粉アレルゲン及び大気汚染物質によるアレルゲンの変性　　　　　　　　　　　　　　　
  王 青躍, 董 詩洋, 高井 優子, 大塚 岳, 関口 和彦, 金子 俊彦
  日本花粉学会第55回大会, Sep. 2014, [Domestic conference]
• CPP-GC/MS法による標準認証物質中PAHsの分析　　　　　　　　　　　　　　　
  関口 和彦, 神山 元美, 王 青曜
  第31回エアロゾル科学・技術研究討論会, Aug. 2014, [Domestic conference]
• 慣性フィルターサンプラーを用いた大気中超微小粒子捕集におけるアーティファクト評価　　　　　　　　　　　　　　　
  関口 和彦, 桑原 博俊, 桜井 健治, 王 青曜, 古内 正美, 畑 光彦
  第31回エアロゾル科学・技術研究討論会, Aug. 2014, [Domestic conference]
• マレーシアのバンギにおけるPM2.5エアロゾルの化学性状　　　　　　　　　　　　　　　
  藤井 佑介, 東野 達, 小田 雅史, Mastura Mahmud, 溝畑 朗, 熊谷貴美代, 関口 和彦
  第31回エアロゾル科学・技術研究討論会, Aug. 2014, [Domestic conference]
• 都市部大気環境における粒子状物質中の多環芳香族炭化水素類の粒径別濃度分布に関する研究　　　　　　　　　　　　　　　
  王 青耀, 小林 佳祐, 周 孟燕, 関口 和彦, 中島 大介, 寺崎 正紀, 呂 森林
  第31回エアロゾル科学・技術研究討論会, Aug. 2014, [Domestic conference]
• 都市沿道における大気中浮遊粒子状物質中の金属成分の粒径分布　　　　　　　　　　　　　　　
  王 青耀, 周 孟燕, 小林 佳祐, 関口 和彦, 中島 大介, 呂 森林
  第31回エアロゾル科学・技術研究討論会, Aug. 2014, [Domestic conference]
• 超音波ミストの粒径分布に与える周波数の影響　　　　　　　　　　　　　　　
  関口 和彦, 工藤 貴久, 王 青曜
  第31回エアロゾル科学・技術研究討論会, Aug. 2014, [Domestic conference]
• 低紫外線強度での家庭用品由来VOCからの室内二次有機エアロゾル(ISOA)の生成　　　　　　　　　　　　　　　
  鈴木 恵, 並木 則和, 藤井 修二, 鍵 直樹, 塩原 緑, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  第31回エアロゾル科学・技術研究討論会, Aug. 2014, [Domestic conference]
• 各種反応器を用いた家庭用品由来VOC からの室内二次有機エアロゾル(ISOA)生成　　　　　　　　　　　　　　　
  鈴木 恵, 並木 則和, 藤井 修二, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英
  第31回空気清浄とコンタミネーションコントロール研究大会, May 2014, [Domestic conference]
• 慣性分級手法とPTFEフィルターを用いた大気中超微小粒子に対する捕集効率の評価　　　　　　　　　　　　　　　
  関口 和彦, 桑原 博俊、王 青躍
  第31回空気清浄とコンタミネーションコントロール研究大会, May 2014, [Domestic conference]
• CPP-GC/MSを用いた粒子中PAHs分析手法の開発　　　　　　　　　　　　　　　
  関口 和彦, 神山 元美、王 青躍
  第31回空気清浄とコンタミネーションコントロール研究大会, May 2014, [Domestic conference]
• オゾンとオゾン分解触媒を用いたVOC分解システムの開発(1)－小型実験装置による性能評価－　　　　　　　　　　　　　　　
  安井 文男, 田村 一, 関口 和彦, 早野 量人
  第31回空気清浄とコンタミネーションコントロール研究大会, May 2014, [Domestic conference]
• オゾンとオゾン分解触媒を用いたVOC分解システムの開発(2)－オゾン分解触媒の違いによるO3とVOCガスの分解特性評価－　　　　　　　　　　　　　　　
  関口 和彦, 早野 量人、王 青躍, 安井 文男, 田村 一
  第31回空気清浄とコンタミネーションコントロール研究大会, May 2014, [Domestic conference]
• 促進酸化雰囲気下での超音波ミストとVOCガスの反応性ならびにミスト生成に与える周波数の影響　　　　　　　　　　　　　　　
  関口 和彦, 工藤 貴久, 並木 孝招, 並木 則和, 東 賢一, 田村 一, 諏訪 好英, 鍵 直樹, 藤井 修二, 志村 哲也
  第31回空気清浄とコンタミネーションコントロール研究大会, May 2014, [Domestic conference]
• Evaluation of gas adsorption during collection of atmospheric ultrafine particles (UFP) using an inertial filter sampler and its application to UFP collection for the metal components analysis　　　　　　　　　　　　　　　
  H. Kuwabara, K. Sekiguchi
  Abstracts of the 2nd Workshop on East Asia Nanoparticle Monirtoinrg Network (EA-Nanonet-2), May 2014, [International conference]
• Characteristics of carbonaceous aerosols emitted from peatland fire in Indonesia　　　　　　　　　　　　　　　
  Y. Fujii, M. Oda, W. Iriana, S. Tohno, P. Lestari, A. Mizohata, T. Kameda, K. Sekiguchi, K. Kumagai
  Abstracts of the 8th Asian Aerosol Conference 2013, Dec. 2013, [International conference]
• Development of an analytical method for PAHs adsorbed on particles using CPP-GC/MS　　　　　　　　　　　　　　　
  K. Sekiguchi, M. Kamiyama, Q. Wang
  Abstracts of the 8th Asian Aerosol Conference 2013, Dec. 2013, [International conference]
• Carbonaceous components in ultrafine and fine particles at roadside environment　　　　　　　　　　　　　　　
  K. H. Kim, S. B. Lee, S. H. Woo, G. N. Bae, K. Sekiguchi, R. Kobayashi, M. Kamiyama, Q. Wang
  Abstracts of the 8th Asian Aerosol Conference 2013, Dec. 2013, [International conference]
• Evaluation of the chemical reactivity of ultrasonic mist with VOC gas using different AOP techniques　　　　　　　　　　　　　　　
  K. Sekiguchi, T. Namiki, Q. Wang, N. Namiki, K. Azuma, H. Tamura, Y. Suwa, N. Kagi, S. Fujii
  Abstracts of the 8th Asian Aerosol Conference 2013, Dec. 2013, [International conference]
• Evaluation of gas adsorption as a positive artifact during collection of atmospheric ultrafine particles using an inertial filter sampler　　　　　　　　　　　　　　　
  K. Sekiguchi, K. Sakurai, Q. Wang, K. H. Kim, M. Furuuchi, M. Hata
  Abstracts of the 8th Asian Aerosol Conference 2013, Dec. 2013, [International conference]
• 大気エアロゾルの基礎とPM2.5　　　　　　　　　　　　　　　
  関口 和彦
  順天堂大学医学部衛生学公衆衛生学合同ゼミ, Oct. 2013, [Invited], [Domestic conference]
• さいたま市と上海市都市部の微小粒子状物質中のPAHsとその変異原性調査　　　　　　　　　　　　　　　
  王 青耀, 小林 佳祐, 中島 大介, 呂 森林, 関口 和彦, 柴田 慶子
  第54回大気環境学会年会, Sep. 2013, [Domestic conference]
• さいたま市都市部沿道における大気浮遊粒子状物質中の金属成分の粒径分布　　　　　　　　　　　　　　　
  王 青耀, 周 孟燕, 中島 大介, 呂 森林, 関口 和彦
  第54回大気環境学会年会, Sep. 2013, [Domestic conference]
• バイオマス焼却周辺で採取したPM2.5、PM1の特徴　　　　　　　　　　　　　　　
  米持 真一, 清水 彩菜, 小林 亮太, 関口 和彦, 坂本 和彦
  第54回大気環境学会年会, Sep. 2013, [Domestic conference]
• CPP-GC/MSを用いた粒子中PAHs分析手法の開発　　　　　　　　　　　　　　　
  関口 和彦, 神山 元美, 王 青躍
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• 性状の異なるオゾン分解触媒を用いたガス状VOCに対する分解傾向の比較　　　　　　　　　　　　　　　
  関口 和彦, 早野 量人, 王 青躍, 安井 文男, 田村 一
  第22回日本オゾン協会年次研究講演会, Aug. 2013, [Domestic conference]
• 飛行時間型エアロゾル質量分析計を用いた道路沿道におけるエアロゾル組成の観測　　　　　　　　　　　　　　　
  萩野 浩之, 関口 和彦, 坂本 和彦
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• スギ花粉主要アレルゲンと共通抗原性をもつ花粉アレルゲンの飛散挙動調査　　　　　　　　　　　　　　　
  王 青躍, 高井 優子, 董 詩洋, ゴン 秀民, 鈴木 美穂, 関口 和彦, 中島 大介
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• さいたま市都市部大気微小粒子中のスギ花粉アレルゲン物質Cryj 1の粒径分布　　　　　　　　　　　　　　　
  王 青躍, ゴン 秀民, 董 詩洋, 高井 優子, 鈴木 美穂, 関口 和彦, 三輪 誠, 中島 大介
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• さいたま市都市部大気中のスギ花粉アレルゲン物質Cry j 1の放出と修飾　　　　　　　　　　　　　　　
  王 青躍, ゴン 秀民, 高井 優子, 鈴木 美穂, 董 詩洋, 関口 和彦, 中島 大介, 三輪 誠
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• スギ花粉と共通抗原性をもつ花粉アレルゲンの粒径別挙動調査　　　　　　　　　　　　　　　
  王 青躍, 高井 優子, 董 詩洋, ゴン 秀民, 鈴木 美穂, 関口 和彦
  日本花粉学会第54回大会, Aug. 2013, [Domestic conference]
• 大気汚染物質によるスギ花粉アレルゲン(Cryj 1)の変性とその生体細胞に対するアポトーシス誘導能の評価　　　　　　　　　　　　　　　
  王 青躍, 董 詩洋, 高井 優子,ゴン 秀民, 鈴木 美穂, 関口 和彦
  日本花粉学会第54回大会, Aug. 2013, [Domestic conference]
• 前駆物質に至る反応経路の分子軌道計算による予測　　　　　　　　　　　　　　　
  諏訪 好英, 鍵 直樹, 山根由衣子, 藤井 修二, 並木 則和, 関口 和彦, 東 賢一, 田村 一
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• 各種ガスバッグを用いた家庭用品由来VOCからの室内二次有機エアロゾル(ISOA)の生成　　　　　　　　　　　　　　　
  鈴木 恵, 並木 則和, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英, 塩原 緑, 鍵 直樹, 藤井 修二
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• 促進酸化手法を用いた超音波ミストの活性化によるVOCガスの分解処理　　　　　　　　　　　　　　　
  関口 和彦, 並木 孝招, 王 青躍, 並木 則和, 東 賢一, 田村 一, 諏訪 好英, 鍵 直樹, 藤井 修二
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• 超音波霧化技術を応用した水中有機汚染物質の気相分解　　　　　　　　　　　　　　　
  関口 和彦, 清水 彩菜, 王 青躍
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• 異なる燃焼条件下での農業廃棄バイオマスから排出される大気汚染物質の特性評価　　　　　　　　　　　　　　　
  王 青躍, 伊藤 真悟, 伊藤 恒一, 周 孟燕, 関口 和彦, 小林 圭祐
  第30回エアロゾル科学・技術研究討論会, Aug. 2013, [Domestic conference]
• 促進酸化手法を用いた超音波ミストの活性化とVOCガスとの反応性評価　　　　　　　　　　　　　　　
  関口 和彦, 並木 孝招, 横山 慶, 王 青躍, 並木 則和
  第30回空気清浄とコンタミネーションコントロール研究大会, Apr. 2013, [Domestic conference]
• 超音波霧化ミストを用いた超微粒子の静電除去　　　　　　　　　　　　　　　
  並木 則和,岩尾 祐樹, 関口 和彦
  第30回空気清浄とコンタミネーションコントロール研究大会, Apr. 2013, [Domestic conference]
• オゾン分解触媒の違いによるO3共存下でのVOC分解特性の評価　　　　　　　　　　　　　　　
  関口 和彦, 早野 量人, 王 青躍, 安井 文男, 田村 一
  第30回空気清浄とコンタミネーションコントロール研究大会, Apr. 2013, [Domestic conference]
• 促進酸化法およびTiO2担持不織布とオゾンマイクロバブルを用いた2-propanolの完全分解　　　　　　　　　　　　　　　
  関口 和彦, 吉田 剛, 王 青躍, 安井 文男, 田村 一, 川崎 達也, 松林 康子
  第30回空気清浄とコンタミネーションコントロール研究大会, Apr. 2013, [Domestic conference]
• 促進酸化手法を用いた超音波ミストの活性化とVOCガスとの反応性評価　　　　　　　　　　　　　　　
  関口 和彦, 並木 孝招, 横山 慶, 王 青躍, 並木 則和
  第30回空気清浄とコンタミネーションコントロール研究大会, Apr. 2013, [Domestic conference]
• キューリーポイントパイロライザーを用いたPAHs迅速分析法の開発　　　　　　　　　　　　　　　
  関口 和彦, 神山 元美, 王 青躍
  第30回空気清浄とコンタミネーションコントロール研究大会, Apr. 2013, [Domestic conference]
• 慣性フィルターサンプラーによる大気中超微小粒子サンプリング時におけるガス吸着アーティファクトの評価　　　　　　　　　　　　　　　
  関口 和彦, 桜井 健治、王 青躍
  第30回空気清浄とコンタミネーションコントロール研究大会, Apr. 2013, [Domestic conference]
• 都市部大気中超微小粒子の大気挙動把握と室内空間を対象としたVOCガスの処理技術　　　　　　　　　　　　　　　
  関口 和彦
  第26回環境工学連合講演会, Apr. 2013, [Invited], [Domestic conference]
• 発生源近傍におけるPM0.1およびPM2.5の成分別大気挙動　　　　　　　　　　　　　　　
  関口 和彦
  第6回環日本海域の環境シンポジウム, Mar. 2013, [Invited], [Domestic conference]
• Motor vehicles contribution to atmospheric bifunctional carbonyl compounds　　　　　　　　　　　　　　　
  R. Ortiz, S. Shimada, K. Sekiguchi, Q. Wang, K. Sakamoto
  Proceedings (CD-ROM) of the 19th International Transport and Air Pollution Conference 2012 (TAP2012), Nov. 2012, [International conference]
• Gas/particle partitioning of bifunctional carbonyl compounds near a roadside in a suburban area　　　　　　　　　　　　　　　
  R. Ortiz, S. Shimada, K. Sekiguchi, Q. Wang, K. Sakamoto
  Proceedings (CD-ROM) of the 19th International Transport and Air Pollution Conference 2012 (TAP2012), Nov. 2012, [International conference]
• Atmospheric behavior of Cryptomeria Japonica pollen and its respirable allergenic particles in an the urban area of Japan　　　　　　　　　　　　　　　
  Q. Wang, X. Gong, S. Nakamura, Y. Takai, M. Suzuki, K. Sekiguchi, S. Lu, D. Nakajima, M. Miwa
  Abstract Book of the International Symposium on Aerosol in East Asia and Their Impacts on Plants and Human Health, Nov. 2012, [International conference]
• 超音波照射雰囲気下でのセルロース糖化プロセスにおける諸因子の影響　　　　　　　　　　　　　　　
  関口 和彦, 林 和平, 田原 裕太, 王 青躍
  第21回ソノケミストリー討論会, Nov. 2012, [Domestic conference]
• 促進酸化手法の違いによる超音波ミストとVOCガスの反応性評価　　　　　　　　　　　　　　　
  関口 和彦, 並木 孝招, 横山 慶, 王 青躍, 並木 則和
  第21回ソノケミストリー討論会, Nov. 2012, [Domestic conference]
• Allergenic species release behavior of Cryptomeria Japonica pollen in rainwater samples simulated for urban polluted atmosphere　　　　　　　　　　　　　　　
  Q. Wang, S. Nakamura, X. Gong, Y. Takai, M. Suzuki, K. Sekiguchi, S. Lu, D. Nakajima, M. Miwa
  Abstract Book of the International Symposium on Aerosol in East Asia and Their Impacts on Plants and Human Health, Nov. 2012, [International conference]
• 超音波霧化技術を応用した水中有機汚染物質の気相分解処理に関する研究　　　　　　　　　　　　　　　
  関口 和彦, 清水 彩菜, 王 青躍
  第21回ソノケミストリー討論会, Nov. 2012, [Domestic conference]
• Behavior of chemical components in ultrafine and fine particles transported from roadside to background sites in a surban area　　　　　　　　　　　　　　　
  K. Sekiguchi, K. H. Kim, M. Kinoshita, K. Sakurai, S. Kudo, Q. Wang
  Abstract Book of the International Symposium on Aerosol in East Asia and Their Impacts on Plants and Human Health, Nov. 2012, [International conference]
• 超音波霧化ミストによる超微粒子の静電捕集　　　　　　　　　　　　　　　
  並木 則和, 関口 和彦
  第21回ソノケミストリー討論会, Nov. 2012, [Domestic conference]
• Secondary organic aerosol formation from p-dichlorobenzene in the indoor air　　　　　　　　　　　　　　　
  Y. Yamane, S. Fujii, N. Kagi, Y. Suwa, N. Namiki, K. Sekiguchi, H. Tamura, K. Azuma
  Proceedings (CD-ROM) of the 21st International Symposium on Contamination Control, Sep. 2012, [International conference]
• Simultaneous decomposition of O3 and VOC with an ozonedecomposition catalyst immobilized on a nonwoven fabric　　　　　　　　　　　　　　　
  K. Sekiguchi, Y. Kurita, N. Namiki, N. Kagi, K. Azuma, H. Tamura, Y. Suwa, S. Fujii
  Proceedings (CD-ROM) of the 21st International Symposium on Contamination Control, Sep. 2012, [International conference]
• Complete decomposition of water-soluble VOC using ozone microbubbles and TiO2 photocatalyst immobilized on a nonwoven fabric　　　　　　　　　　　　　　　
  K. Sekiguchi, T. Yoshida, Q. Wan, K. H. Kim, F. Yasui, H. Tamura, T. Kawasaki, Y. Matsubayashi
  Proceedings (CD-ROM) of the 21st International Symposium on Contamination Control, Sep. 2012, [International conference]
• 道路近傍からの距離にともなうPM2.5およびPM0.1の化学成分変化　　　　　　　　　　　　　　　
  関口 和彦, 木下勝利史, 金 庚煥, 工藤 慎治, 王 青耀
  第53回大気環境学会年会, Sep. 2012, [Domestic conference]
• 関東地方におけるPM2.5無機イオンの高時間分解同時観測－夏季と初冬季との比較－　　　　　　　　　　　　　　　
  米持 真一, 長谷川就一, 萩野 浩之, 山口 直哉, 熊谷貴美代, 関口 和彦, 飯島 明宏, 速水 洋
  第53回大気環境学会年会, Sep. 2012, [Domestic conference]
• 大気中超微小粒子捕集における慣性フィルターサンプラーの性能評価　　　　　　　　　　　　　　　
  関口 和彦, 桜井 健治, 王 青耀
  第53回大気環境学会年会, Sep. 2012, [Domestic conference]
• 2011年夏季関東都市・郊外におけるエアロゾル質量スペクトルのPMF解析　　　　　　　　　　　　　　　
  萩野 浩之, 森川多津子, 長谷川就一, 米持 真一, 関口 和彦, 森田 諒, 熊谷貴美代, 山口 直哉, 飯島 明宏, 嶋寺 光, 速水 洋
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 二次粒子生成の検討における分子軌道計算の応用　　　　　　　　　　　　　　　
  諏訪 好英, 山根由依子, 鍵 直樹, 藤井 修二, 並木 則和, 関口 和彦, 東 賢一, 田村 一
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• オゾンマイクロバブルと光触媒を用いた液相中有機物質分解に関する研究(3)－リアクター性能への流量変化および不織布形状の影響－　　　　　　　　　　　　　　　
  安井 文男, 田村 一, 関口 和彦, 吉田 剛, 松林 康子, 川崎 達也
  日本混相流学会年会講演会2012, Aug. 2012, [Domestic conference]
• オゾンマイクロバブルと光触媒不織布を用いた水中2-プロパノールの無機化処理　　　　　　　　　　　　　　　
  関口 和彦, 吉田 剛, 王 青躍, 安井 文男, 田村 一, 川崎 達也, 松林 康子
  日本混相流学会年会講演会2012, Aug. 2012, [Domestic conference]
• 超音波ミストできれいな空気を創造できるのか？　　　　　　　　　　　　　　　
  清水 彩菜, 関口 和彦, 並木 則和
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 紫外線照射下におけるNOx添加による家庭用製品由来VOCからの二次粒子生成 その１ 模擬住宅居室を用いた検討　　　　　　　　　　　　　　　
  鍵 直樹, 山根由依子, 藤井 修二, 並木 則和, 諏訪 好英, 関口 和彦, 東 賢一, 田村 一
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 紫外線照射下におけるNOx添加による家庭用製品由来VOCからの二次粒子生成 その２ ガスバッグを用いたVOC単成分からの生成の検討　　　　　　　　　　　　　　　
  山根由依子, 藤井 修二, 鍵 直樹, 並木 則和, 諏訪 好英, 関口 和彦, 東 賢一, 田村 一
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 模擬蒸気を用いたレーザープリンタから生成する超微粒子の生成機構解明とその生成抑制　　　　　　　　　　　　　　　
  並木 則和, 鍵 直樹, 藤井 修二, 諏訪 好英, 関口 和彦, 東 賢一, 田村 一
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 室内環境条件下での二次有機エアロゾルの生成と評価　　　　　　　　　　　　　　　
  関口 和彦, 工藤 慎治, 藤井 修二, 鍵 直樹, 並木 則和, 諏訪 好英, 東 賢一, 田村 一
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• ナノ粒子の生体影響に関する近年の知見　　　　　　　　　　　　　　　
  東 賢一, 並木 則和, 鍵 直樹, 関口 和彦,諏訪 好英, 田村 一, 藤井 修二
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 油凝集選炭法における石炭種の影響因子の調査　　　　　　　　　　　　　　　
  王 青躍, 新井田大貴, アパルパタル, 陳 啓宇, 三村 直輝, 関口 和彦
  第21回エネルギー学会, Aug. 2012, [Domestic conference]
• 道路近傍からの距離にともなう大気中超微小粒子の化学成分変化　　　　　　　　　　　　　　　
  関口 和彦, 木下勝利史, 金 庚煥, 工藤 慎治, 王 青躍
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 夏季と冬季の関東地方におけるPM2.5成分の高時間分解同時観測　　　　　　　　　　　　　　　
  長谷川就一, 米持 真一, 熊谷貴美代, 山口 直哉, 萩野 浩之, 関口 和彦, 飯島 明宏, 嶋寺 光, 速水 洋
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 廃棄籾殻の燃料利用時における大気浮遊粒子状物質の排出挙動　　　　　　　　　　　　　　　
  王 青躍, 伊藤 真悟, 前薗 拓矢, 伊藤 恒一, 関口 和彦, 板野 史明
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 慣性フィルターサンプラーを用いた大気中超微小粒子捕集におけるガス吸着量の評価　　　　　　　　　　　　　　　
  関口 和彦, 桜井 健治, 王 青躍
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 2011年度さいたま市におけるスギ花粉およびそのアレルゲン飛散挙動の調査　　　　　　　　　　　　　　　
  仲村 慎一, 王 青躍, 董 詩洋, 高井 優子, 関口 和彦, 鈴木 美穂, 中島 大介
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• スギ花粉主要アレルゲンと共通抗原性をもつ花粉アレルゲンの飛散量調査　　　　　　　　　　　　　　　
  王 青躍, 高井 優子, 中島 拓也, 仲村 慎一, ゴン 秀民, 鈴木 美穂, 関口 和彦, 中島 大介
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• ニトロ化スギ花粉アレルゲンにおけるアポトーシス誘導能の検討　　　　　　　　　　　　　　　
  王 青躍, 董 詩洋, 森田 淳, 鈴木 美穂, 仲村 慎一, ゴン 秀民, 関口 和彦, 中島 大介
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 超音波ミストを用いた気液相有機汚染物質の分解　　　　　　　　　　　　　　　
  関口 和彦, 清水 彩菜, 横山 慶, 並木 孝招, 王 青躍, 並木 則和
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• 二官能基型カルボニル化合物の大気中における挙動　　　　　　　　　　　　　　　
  オルティス リカルド, 島田 悟, 関口 和彦, 王 青躍, 坂本 和彦
  第29回エアロゾル科学・技術研究討論会, Aug. 2012, [Domestic conference]
• Secondary organic aerosol formation form volatile organic compounds emitted from various kinds of house-keeping products　　　　　　　　　　　　　　　
  N. Kagi, S. Fujii, N. Namiki, Y. Suwa, K. Sekiguchi, K. Azuma, H. Nakagawa, M. Shinohara
  Proceedings (CD-ROM) of the International Conference on 10th Healthy Buildings, Jul. 2012, [International conference]
• 超音波霧化ミストを用いた超微粒子の静電除去　　　　　　　　　　　　　　　
  並木 則和, 笹原 香瑠, 関口 和彦
  第29回空気清浄とコンタミネーションコントロール研究大会, Jun. 2012, [Domestic conference]
• 二酸化チタン光触媒とオゾンマイクロバブルを用いた2-プロパノールの完全分解　　　　　　　　　　　　　　　
  関口 和彦, 吉田 剛, 王 青躍, 金 庚煥, 安井 文男, 田村 一, 川崎 達也, 松林 康子
  第29回空気清浄とコンタミネーションコントロール研究大会, Jun. 2012, [Domestic conference]
• 固定化オゾン分解触媒を用いたオゾン存在下でのVOCガスの分解　　　　　　　　　　　　　　　
  関口 和彦, 栗田 優樹, 並木 則和, 鍵 直樹, 東 賢一, 田村 一, 諏訪 好英, 藤井 修二
  第29回空気清浄とコンタミネーションコントロール研究大会, Jun. 2012, [Domestic conference]
• 二次粒子生成の検討における分子軌道計算の応用　　　　　　　　　　　　　　　
  諏訪 好英, 山根由衣子, 鍵 直樹, 藤井 修二, 並木 則和, 関口 和彦, 東 賢一, 田村 一
  第29回空気清浄とコンタミネーションコントロール研究大会, Jun. 2012, [Domestic conference]
• 室内空間におけるVOCのUV照射による二次有機エアロゾル生成について　　　　　　　　　　　　　　　
  山根由衣子, 藤井 修二, 鍵 直樹, 松下 大紀, 中村友香莉, 並木 則和, 諏訪 好英, 関口 和彦, 東 賢一, 田村 一
  第29回空気清浄とコンタミネーションコントロール研究大会, Jun. 2012, [Domestic conference]
• 模擬蒸気を用いたレーザープリンタから発生する超微粒子の生成機構の試み　　　　　　　　　　　　　　　
  並木 則和, 海老塚 恵, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英, 藤井 修二
  第29回空気清浄とコンタミネーションコントロール研究大会, Jun. 2012, [Domestic conference]
• ナノサンプラーによる大気中超微小粒子の観測と空気浄化手法への微細な霧や泡の応用　　　　　　　　　　　　　　　
  関口 和彦
  第１回微粒子プロセス研究会, Jan. 2012, [Invited], [Domestic conference]
• 廃棄石炭利用バイオブリケット中の金属成分によるガス化への影響　　　　　　　　　　　　　　　
  王 青躍, オウ イビン, 前園 拓也, アパル バタル, 関口 和彦
  第7回バイオマス科学会議, Jan. 2012, [Domestic conference]
• バーチャルインパクタにより分離捕集した固定発生源からのPM10/PM2.5排出濃度と化学組成　　　　　　　　　　　　　　　
  和田 匡司, 神谷 秀博, 塚田まゆみ, 並木 則和, 関口 和彦, 金 庚煥, 東野 達, 奥村 智憲, R. B. Mat, M. R. M. Yusof, W. W. Szymanski
  「東アジアにおけるエアロゾルの植物・人間系へのインパクト」シンポジウム, Jan. 2012, [Domestic conference]
• 道路近傍大気における微小粒子および超微小粒子成分のPMF解析結果　　　　　　　　　　　　　　　
  工藤 慎治, 関口 和彦, 木下勝利史, 桜井 健治
  「東アジアにおけるエアロゾルの植物・人間系へのインパクト」シンポジウム, Jan. 2012, [Domestic conference]
• 地点間における大気中超微小粒子の挙動解明　　　　　　　　　　　　　　　
  関口 和彦, 木下勝利史, 工藤 慎治, 桜井 健治
  「東アジアにおけるエアロゾルの植物・人間系へのインパクト」シンポジウム, Jan. 2012, [Domestic conference]
• 慣性フィルターサンプラーのアーティファクト評価　　　　　　　　　　　　　　　
  関口 和彦, 桜井 健治, 木下勝利史, 工藤 慎治
  「東アジアにおけるエアロゾルの植物・人間系へのインパクト」シンポジウム, Jan. 2012, [Domestic conference]
• 大気中超微小粒子成分を指標とした発生源影響評価とアジア地域におけるフィールド観測　　　　　　　　　　　　　　　
  関口 和彦, 工藤 慎治, 木下勝利史, 桜井 健治
  「東アジアにおけるエアロゾルの植物・人間系へのインパクト」シンポジウム, Jan. 2012
• 大気中超微小粒子成分を指標とした発生源影響評価とアジア地域におけるフィールド観測　　　　　　　　　　　　　　　
  関口 和彦, 工藤 慎治, 木下勝利史, 桜井健治
  「東アジアにおけるエアロゾルの植物・人間系へのインパクト」シンポジウム, Jan. 2012, [Domestic conference]
• Fundamental study on a biomass saccharification process using an ultrasonic wave and a solid acid catalyst　　　　　　　　　　　　　　　
  Y. Tahara, K. Sekiguchi, Q. Wang
  Proceedings of the 20th Annual Meeting of the Japan Society of Sonochemistry & The International Workshop on Advanced Sonochemistry, Nov. 2011, [International conference]
• 都市部汚染大気によるスギ花粉アレルゲン・タンパク質のニトロ化と3-ニトロチロシンのアポトーシス誘導能の評価　　　　　　　　　　　　　　　
  森田 淳, 王 青躍, ゴン 秀民, 仲村 慎一, 鈴木 美穂, 中島 拓也, 関口 和彦, 中島 大介, 三輪 誠
  第52回大気環境学会年会, Sep. 2011, [Domestic conference]
• 交差点付近からのPM2.5およびPM0.1の成分別距離減衰　　　　　　　　　　　　　　　
  関口 和彦, 金 庚煥, 工藤 慎治, 木下 勝利史, 坂本 和彦, 王 青耀
  第52回大気環境学会年会, Sep. 2011, [Domestic conference]
• 道路沿道ならびにバックグラウンド大気におけるPM2.5とPM0.1の化学成分挙動　　　　　　　　　　　　　　　
  関口 和彦, 木下 勝利史, 工藤 慎治, 金 庚煥, 坂本 和彦, 王 青耀
  第52回大気環境学会年会, Sep. 2011, [Domestic conference]
• 中国農村部におけるバイオマス燃焼により排出される炭素粒子の特性に関する研究　　　　　　　　　　　　　　　
  伊藤 恒一, 関口 和彦, 王 青躍, 坂本 和彦
  第52回大気環境学会年会, Sep. 2011, [Domestic conference]
• 飛行時間型エアロゾル質量分析計を用いた冬季埼玉県北部における微小粒子中の有機成分の化学的特性　　　　　　　　　　　　　　　
  萩野 浩之, 森川 多津子, 長谷川 就一, 米持 真一, 熊谷 貴美代, 山口 直哉, 関口 和彦, 飯島 明宏, 速水 洋
  第52回大気環境学会年会, Sep. 2011, [Domestic conference]
• 初冬季の関東地方におけるPM2.5炭素成分の高時間分解同時観測　　　　　　　　　　　　　　　
  長谷川 就一, 米持 真一, 萩野 浩之, 関口 和彦, 熊谷 貴美代, 山口 直哉, 飯島 明宏, 速水 洋
  第52回大気環境学会年会, Sep. 2011, [Domestic conference]
• 初冬季の関東地方におけるPM2.5無機イオンの高時間分解同時観測　　　　　　　　　　　　　　　
  米持 真一, 長谷川 就一, 萩野 浩之, 関口 和彦, 熊谷 貴美代, 山口 直哉, 飯島 明宏, 速水 洋
  第52回大気環境学会年会, Sep. 2011, [Domestic conference]
• 家庭用品由来揮発性有機化合物からの二次粒子生成（その1）－ガスバッグおよび模擬居室を用いた検証－　　　　　　　　　　　　　　　
  並木 則和, 鍵 直樹, 西村 直也, 関口 和彦, 東 賢一, 田村 一, 塩原 緑, 中川 央絵, 諏訪 好英, 藤井 修二
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• 家庭用品由来揮発性有機化合物からの二次粒子生成（その2）－パラジクロロベンゼン単成分蒸気からのISOA生成の可能性－　　　　　　　　　　　　　　　
  鍵 直樹, 並木 則和, 関口 和彦, 東 賢一, 田村 一, 中川 央絵, 塩原 緑, 諏訪 好英, 藤井 修二
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• チャンバーを用いた室内環境条件での二次有機粒子生成に関する研究　　　　　　　　　　　　　　　
  工藤 慎治, 関口 和彦, 坂本 和彦, 藤井 修二, 並木 則和, 西村 直也, 鍵 直樹, 東 賢一, 諏訪 好英, 田村 一
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• 二次粒子生成過程における超微粒子の粒径分布変化に関するモデリング　　　　　　　　　　　　　　　
  諏訪 好英, 藤井 修二, 並木 則和, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 西村 直也
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• ナノ粒子による生体影響と健康リスク　　　　　　　　　　　　　　　
  東 賢一, 並木 則和, 鍵 直樹, 関口 和彦, 諏訪 好英, 田村 一, 西村 直也, 藤井 修二
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• レーザープリンターから発生する超微粒子の生成機構の検討　　　　　　　　　　　　　　　
  並木 則和, 鍵 直樹,関口 和彦, 西村 直也, 東 賢一, 田村 一, 諏訪 好英, 藤井 修二
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• 交差点付近の道路近傍におけるPM0.1とPM2.5の化学成分に関する研究(1)－炭素成分の挙動－　　　　　　　　　　　　　　　
  関口 和彦, 金 庚煥, 工藤 慎治, 木下 勝利史, 王 青躍
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• 交差点付近の道路近傍におけるPM0.1とPM2.5の化学成分に関する研究(2)－イオン成分の挙動－　　　　　　　　　　　　　　　
  金 庚煥, 関口 和彦, 工藤 慎治, 木下 勝利史, 王 青躍
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• オゾンマイクロバブルと光触媒を用いた液相中有機物質分解に関する研究(1)－MB発生器の違いによる影響－　　　　　　　　　　　　　　　
  安井 文男, 田村 一, 関口 和彦, 金 庚煥, 北代 哲也
  日本混相流学会年会講演会2011講演論文集, Aug. 2011, [Domestic conference]
• オゾンマイクロバブルと光触媒を用いた液相中有機物質分解に関する研究(2)－除去率に与える諸因子の影響と分解生成物評価－　　　　　　　　　　　　　　　
  関口 和彦, 北代 哲也, 金 庚煥, 田村 一, 安井 文男
  日本混相流学会年会講演会2011講演論文集, Aug. 2011, [Domestic conference]
• 新規TiO2固定化反応器とオゾンマイクロバブルを用いた有機成分の高効率液相光触媒分解　　　　　　　　　　　　　　　
  金 庚煥, 関口 和彦, 吉田 剛, 安井 文男, 田村 一
  日本混相流学会年会講演会2011講演論文集, Aug. 2011, [Domestic conference]
• Comprehensive physical and chemical characterization of urban aerosols in Vienna, Austria　　　　　　　　　　　　　　　
  N. S. Kupelwieser, K. Sekiguchi, K. H. Kim, H. Kamiya, W. W. Szymanski
  Proceedings of the 7th Asian Aerosol Conference, Aug. 2011, [International conference]
• 2011年度のさいたま市に飛来したスギ花粉の飛散挙動　　　　　　　　　　　　　　　
  仲村 慎一, 王 青躍, ゴン 秀民, 森田 淳, 中島 拓也, 関口 和彦, 鈴木 美穂, 中島 大介
  第28回エアロゾル科学・技術研究討論会, Aug. 2011, [Domestic conference]
• Influence of intersection on chemical composition of atmospheric particulate matters observed at roadside environment in urban area　　　　　　　　　　　　　　　
  K. H. Kim, K. Sekiguchi, S. Kudo, M. Kinoshita, K. Sakamoto
  Proceedings of the 7th Asian Aerosol Conference, Aug. 2011, [International conference]
• Diurnal variation of chemical composition in ultrafine and fine particles in urban area　　　　　　　　　　　　　　　
  K. H. Kim, T. Okamoto, S. Sato, R. Ortiz, K. Sekiguchi, S. Chatani, T. Morikawa, H. Minoura, K. Sakamoto
  Proceedings of the 7th Asian Aerosol Conference, Aug. 2011, [International conference]
• Emission source of atmospheric ultrafine particles clarified by simultaneous sampling and data comparison with PM2.5　　　　　　　　　　　　　　　
  K. Sekiguchi, M. Kinoshita, S. Kudo, K. H. Kim, Q. Wang, K. Sakamoto
  Proceedings of the 7th Asian Aerosol Conference, Aug. 2011, [International conference]
• 一般住宅居室における家庭用品由来VOCからの二次有機エアロゾルの生成　　　　　　　　　　　　　　　
  並木 則和, 越智 翔平, 小瀬 雄一郞, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 塩原 緑, 中川 央絵, 諏訪 好英, 藤井 修二
  第28回空気清浄とコンタミネーションコントロール研究大会, Jul. 2011, [Domestic conference]
• オゾン分解触媒によるオゾン存在下でのVOCガス分解効率の評価　　　　　　　　　　　　　　　
  関口 和彦, 栗田 優樹, 其田 貴光, 並木 則和, 鍵 直樹, 東 賢一, 諏訪 好英, 田村 一, 藤井 修二
  第28回空気清浄とコンタミネーションコントロール研究大会, Jul. 2011, [Domestic conference]
• 二次粒子生成過程における超微粒子の粒径分布変化に関するモデリングと数値シミュレーション　　　　　　　　　　　　　　　
  諏訪 好英, 藤井 修二, 並木 則和, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 西村 直也
  第28回空気清浄とコンタミネーションコントロール研究大会, Jul. 2011, [Domestic conference]
• UVとオゾンによる室内中VOCのエアロゾル生成　　　　　　　　　　　　　　　
  塩原 緑, 藤井 修二, 諏訪 好英, 中川 央絵, 並木 則和, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一
  第28回空気清浄とコンタミネーションコントロール研究大会, Jul. 2011, [Domestic conference]
• 住宅空間におけるUV照射による二次有機エアロゾルの生成　　　　　　　　　　　　　　　
  中川 央絵, 藤井 修二, 諏訪 好英, 塩原 緑, 並木 則和, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一
  第28回空気清浄とコンタミネーションコントロール研究大会, Jul. 2011, [Domestic conference]
• レーザープリンターから発生する超微粒子の生成機構の解明　　　　　　　　　　　　　　　
  並木 則和, 鈴木 和也, 鍵 直樹, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英, 藤井 修二
  第28回空気清浄とコンタミネーションコントロール研究大会, Jul. 2011, [Domestic conference]
• Modeling and computer simulation of ultrafine particles generated fom lser pinters　　　　　　　　　　　　　　　
  Y. Suwa, S. Fujii, N. Namiki, N. Kagi, K. Sekiguchi, K. Azuma, H. Tamura
  Proceedings of the 12th International Conference on Indoor Air Quality and Climate; Indoor Air 2011, Jun. 2011, [International conference]
• Health risks and toxic effects of indoor secondary organic aerosols　　　　　　　　　　　　　　　
  K. Azuma, N. Namiki, N. Nishimura, K. Sekiguchi, N. Kagi, H. Tamura, Y. Suwa, S. Fujii
  Proceedings of the 12th International Conference on Indoor Air Quality and Climate; Indoor Air 2011, Jun. 2011, [International conference]
• 最近の研究テーマ紹介：大気中超微小粒子観測と超音波霧化分離　　　　　　　　　　　　　　　
  関口 和彦
  日本エアロゾル学会若手会第6回若手フォーラム, Feb. 2011, [Invited], [Domestic conference]
• Secondary particle formation volatile organic compounds emitted from various house-keeping wares used in indoor environment　　　　　　　　　　　　　　　
  S. Fujii, T. Hara, R. Takahashi, Y. Suwa, N. Kagi, N. Namiki, N. Nishimura, K. Sekiguchi, K. Azuma, T. H. Min
  Proceedings of the 8th International Symposium on Building and Urban Environmental Engineering, BUEE2010, Nov. 2010, [International conference]
• Characterization of ultrafine particle generation from laser printers using different types of chambers　　　　　　　　　　　　　　　
  N. Namiki, N. Kagi, N. Nishimiura, K. Sekiguchi, K. Azuma, H. Tamura, Y. Suwa, S. Fujii
  Proceedings of the 20th International Symposium on Contamination Control, Oct. 2010, [International conference]
• Photocatalytic degradation of VOC gases introduced into water as minute bubbles　　　　　　　　　　　　　　　
  K. Sekiguchi, W. Morinaga, Y. Ohira, K. H. Kim, K. Sakamoto, H. Tamura, F. Yasui
  Proceedings of the 20th International Symposium on Contamination Control, Oct. 2010, [International conference]
• Formation of secondary organic aerosol from VOCs in indoor environment　　　　　　　　　　　　　　　
  T. Hara, R. Takahashi, N. Namiki, N. Nishimura, K. Sekiguchi, N. Kagi, K. Azuma, Y. Suwa, H. Tamura, S. Fujii
  Proceedings of the 20th International Symposium on Contamination Control, Oct. 2010, [International conference]
• Study on decomposition of organic substance in liquid phase using several micro bubble generators and photocatalyst　　　　　　　　　　　　　　　
  F. Yasui, H. Tamura, K. Sekiguchi, Y. Ohira
  Proceedings of the 20th International Symposium on Contamination Control, Oct. 2010, [International conference]
• 石炭中の酸素含有率変化による油凝集選炭効率への影響評価　　　　　　　　　　　　　　　
  王 青躍, 新井田大貴, アパルパタル, 陳 啓宇, 前園 拓矢, 関口 和彦
  第48回石炭科学会議, Oct. 2010, [Domestic conference]
• 反応活性種を付与した超音波霧によるVOCガスの処理　　　　　　　　　　　　　　　
  関口 和彦, 半田美沙子、坂本 和彦, 並木 則和
  化学工学会第42回秋季大会, Sep. 2010, [Domestic conference]
• Cryofocusing-CPP-GC/MS法を用いた大気粒子中n-alkanesおよびPAHs成分に対する分析手法の最適化　　　　　　　　　　　　　　　
  金 庚煥, 関口 和彦, 工藤 慎治, 坂本 和彦
  第51回大気環境学会年会, Sep. 2010, [Domestic conference]
• 中国農村部のカンによるバイオマス燃焼時に排出される微小粒子中の炭素成分の測定(2)　　　　　　　　　　　　　　　
  伊藤 恒一, 岡本 敬義, 姜 兆武, 関口 和彦, 王 青躍, 坂本 和彦
  第51回大気環境学会年会, Sep. 2010, [Domestic conference]
• 上海都市部における微小粒子状物質の挙動とその変異原性の調査　　　　　　　　　　　　　　　
  王 青躍, 孫 楊, 坂本 和彦, 関口 和彦, 中島 大介, 呂 森林, 柴田 慶子
  第51回大気環境学会年会, Sep. 2010, [Domestic conference]
• タイ北部の固定発生源から排出される超微小粒子および微小粒子の組成特性　　　　　　　　　　　　　　　
  工藤 慎治, 関口 和彦, 金 庚煥, 坂本 和彦, 古内 正美, 畑 光彦, ポンピアチャン スイワット
  第51回大気環境学会年会, Sep. 2010, [Domestic conference]
• Performance test of an inertial fibrous filter sampler for ultrafine particle collection and its application to the field sampling at roadside　　　　　　　　　　　　　　　
  K. H. Kim, K. Sekiguchi, S. Kudo, K. Sakamoto, M. Furuuchi
  Abstracts of the 8th International Aerosol Conference 2010, Sep. 2010, [International conference]
• ナノ粒子による生体への影響について　　　　　　　　　　　　　　　
  東 賢一, 並木 則和, 西村 直也, 関口 和彦, 鍵 直樹, 田村 一, 諏訪 好英, 藤井 修二
  第27回エアロゾル科学・技術研究討論会, Aug. 2010, [Domestic conference]
• 室内由来揮発性有機化合物からの二次粒子生成　　　　　　　　　　　　　　　
  並木 則和, 西村 直也, 関口 和彦, 鍵 直樹, 東 賢一, 田村 一, 諏訪 好英, 藤井 修二
  第27回エアロゾル科学・技術研究討論会, Aug. 2010, [Domestic conference]
• レーザープリンタからの超微粒子発生量の測定　　　　　　　　　　　　　　　
  並木 則和, 西村 直也, 関口 和彦, 鍵 直樹, 東 賢一, 田村 一, 諏訪 好英, 藤井 修二
  第27回エアロゾル科学・技術研究討論会, Aug. 2010, [Domestic conference]
• 微小粒子ならびに超微小粒子中のchar-, soot-EC特性　　　　　　　　　　　　　　　
  金 庚煥, 関口 和彦, 坂本 和彦, 古内 正美, 畑 光彦
  第27回エアロゾル科学・技術研究討論会, Aug. 2010, [Domestic conference]
• 高熱流束マイクロプラズマを用いた酸化チタンナノ粒子の合成　　　　　　　　　　　　　　　
  関口 和彦, 栗田 優樹, 坂本 和彦, 並木 則和
  第27回エアロゾル科学・技術研究討論会, Aug. 2010, [Domestic conference]
• 室内環境を意図した二次有機エアロゾル生成に関する研究　　　　　　　　　　　　　　　
  関口 和彦, 工藤 慎治, 坂本 和彦, 古内 正美, 藤井 修二, 並木 則和, 西村 直也, 鍵 直樹, 東 賢一, 諏訪 好英, 田村 一
  第27回エアロゾル科学・技術研究討論会, Aug. 2010, [Domestic conference]
• 中国農村部のカンによるバイオマス燃焼時に排出される微小粒子中の炭素成分の測定　　　　　　　　　　　　　　　
  岡本 敬義、姜 兆武、佐藤 慎平、関口 和彦、王 青躍、坂本 和彦
  第27回エアロゾル科学・技術研究討論会, Aug. 2010, [Domestic conference]
• Evaluation of the PMF and CMB models using submicron aerosol mass spectra collected on the inland Kanto plain, Japan during summer of 2008　　　　　　　　　　　　　　　
  H. Hagino, S. Sasaki, A. Nakayama, K. Kumagai, A. Tatami, S. Hasegawa, K. Sekiguchi
  Abstracts of the 8th International Aerosol Conference 2010, Aug. 2010, [International conference]
• Comparison of carbonaceous and ionic compounds in ultrafine particles between Japan and Germany　　　　　　　　　　　　　　　
  S. Kudo, K. Sekiguchi, K. H. Kim, K. Sakamoto, D. Möller
  Abstracts of the 8th International Aerosol Conference 2010, Aug. 2010, [International conference]
• Secondary organic aerosol (ISOA) from VOCs in indoor environment　　　　　　　　　　　　　　　
  T. H. Min, T. Hara, R. Takahashi, N. Namiki, N. Nishimura, K. Sekiguchi, N. Kagi, K. Azuma, Y. Suwa, H. Tamura, S. Fujii
  Abstracts of the 8th International Aerosol Conference 2010, Aug. 2010, [International conference]
• 異なるチャンバを用いたレーザープリンタから発生する超微粒子の発生量評価　　　　　　　　　　　　　　　
  並木 則和, 設楽 俊平, 鍵 直樹, 西村 直也, 関口 和彦, 東 賢一, 田村 一, 諏訪 好英, 藤井 修二
  プレISCC2010空気清浄とコンタミネーションコントロール研究発表会, Jun. 2010, [Domestic conference]
• Health effects due to indoor secondary organic aerosols: Literature reviews and recommendations for future research　　　　　　　　　　　　　　　
  K. Azuma, N. Namiki, N. Nishimura, K. Sekiguchi, N. Kagi, H. Tamura, Y. Suwa, S. Fujii
  Abstracts of the 3rd Nanotoxicology 2010, Jun. 2010, [International conference]
• 室内空気中の揮発性有機化合物に起因する二次有機エアロゾル(ISOA)の生成　　　　　　　　　　　　　　　
  原 太一郎, 高橋 理恵, 並木 則和, 西村 直也, 関口 和彦, 鍵 直樹, 東 賢一, 諏訪 好英, 田村 一, 藤井 修二
  プレISCC2010空気清浄とコンタミネーションコントロール研究発表会, Jun. 2010, [Domestic conference]
• 石炭中の酸素含有率変化による油凝集選炭効率への影響評価　　　　　　　　　　　　　　　
  王 青躍, 新井田大貴, アパルパタル, 陳 啓宇, 前園 拓矢, 関口 和彦
  第48回石炭科学会議, 2010, [Domestic conference]
• Measurements for the carbonaceous and ionic components of atmospheric ultrafine particles using an impactor filter　　　　　　　　　　　　　　　
  S. Kudo, K. Sekiguchi, K. Sakamoto, Y. Otani
  Abstracts of the 6th Asian Aerosol Conference, Nov. 2009, [International conference]
• Performance of new samplers based on “Internal filter” technology applied for classification of ambient aerosol nano-particles　　　　　　　　　　　　　　　
  M. Hata, M. Fukumoto, M. Furuuchi, Y. Otani, K. H. Kim, K. Sekiguchi, N. Tajima, Y. Bai
  Abstracts of the 6th Asian Aerosol Conference, Nov. 2009, [International conference]
• Organic fine particles analysis during photochemical active event using high resolution aerosol mass spectrometry at central japan　　　　　　　　　　　　　　　
  H. Hagino, S. Sakai, A. Nakayama, K. Kumagai, A. Iijima, M. Shimoda, A. Takami, S. Hasegawa, S. Kobayashi, K. Sekiguchi
  Abstracts of the 6th Asian Aerosol Conference, Nov. 2009, [International conference]
• Characteristics of ultra-fine and fine particles in road tunnel　　　　　　　　　　　　　　　
  M. Hata, M. Furuuchi, M. Fukumoto, Y. Otani, K. Sekiguchi, N. Tajima, Y. Bai
  Abstracts of the 6th Asian Aerosol Conference, Nov. 2009, [International conference]
• VOC分解のための反応活性霧の生成に関する基礎的検討　　　　　　　　　　　　　　　
  関口 和彦, 半田美沙子, 坂本 和彦
  第18回ソノケミストリー討論会, Oct. 2009, [Domestic conference]
• 都市部道路端における浮遊粒子状物質中のイオン及び炭素成分の特性解析　　　　　　　　　　　　　　　
  胡 舜尭, 孫 陽, 王 青躍, 坂本 和彦, 関口 和彦
  第50回大気環境学会年会, Sep. 2009, [Domestic conference]
• 2008年夏季関東内陸部における大気微小粒子組成の高時間分解観測　　　　　　　　　　　　　　　
  荻野 浩之, 中山 明美, 佐々木左宇介, 熊谷貴美代, 飯島 明宏, 下田 美里, 高見 昭憲, 長谷川就一, 小林 伸治, 関口 和彦
  第50回大気環境学会年会, Sep. 2009, [Domestic conference]
• エアロゾル質量分析とアニューラデニューダー－フィルターパック法による都市近郊大気観測　　　　　　　　　　　　　　　
  島田 悟, 大須賀肇太, 高田 智至, 森川多津子, 下 伸朗, 箕浦 宏明, 速水 洋, 関口 和彦, 坂本 和彦
  第50回大気環境学会年会, Sep. 2009, [Domestic conference]
• 大気微小粒子中のレボグルコサンと炭素成分に関する調査　　　　　　　　　　　　　　　
  大須賀肇太, 島田 悟, 下 伸朗, 箕浦 宏明, 小林 伸治, 佐々木 寛介, 森川多津子, 関口 和彦, 坂本 和彦
  第50回大気環境学会年会, Sep. 2009, [Domestic conference]
• 高熱流束マイクロプラズマによるVOCと排気ガス由来超微粒子の同時除去　　　　　　　　　　　　　　　
  並木 則和, 松本 雄紀, 関口 和彦, 長谷川靖洋
  化学工学会第41回秋季大会, Sep. 2009, [Domestic conference]
• 超音波霧化法による懸濁液からの超微粒子域試験粒子の発生　　　　　　　　　　　　　　　
  並木 則和, 関口 和彦, 井川 誠司
  第26回エアロゾル科学・技術研究討論会, Aug. 2009, [Domestic conference]
• マイクロバブル化手法を用いた気相汚染物質の水中捕集とその液相中光触媒分解に関する研究　　　　　　　　　　　　　　　
  関口 和彦, 大平 泰生, 坂本 和彦, 田村 一, 安井 文男
  日本混相流学会年会講演会2009講演論文集, Aug. 2009, [Domestic conference]
• 各種マイクロバブル発生器と光触媒を用いた液相中有機物質分解に関する研究　　　　　　　　　　　　　　　
  安井 文男, 田村 一, 関口 和彦, 大平 泰生
  日本混相流学会年会講演会2009講演論文集, Aug. 2009, [Domestic conference]
• 炭素成分およびイオン成分からみた慣性フィルタの性能評価　　　　　　　　　　　　　　　
  関口 和彦, 金 庚煥, 工藤 慎治, 坂本 和彦, 古内 正美, 畑 光彦, 大谷 吉生, 田島奈穂子
  第26回エアロゾル科学・技術研究討論会, Aug. 2009, [Domestic conference]
• 粒子中PAHs特性に基づく慣性フィルタの大気エアロゾル粒子分離捕集特性の考察　　　　　　　　　　　　　　　
  福本 将秀, 畑 光彦, 大谷 吉生, 古内 正美, 白 雲鶴, 関口 和彦, 田島奈穂子
  第26回エアロゾル科学・技術研究討論会, Aug. 2009, [Domestic conference]
• 関東内陸域（群馬県）における超微小粒子成分の観測　　　　　　　　　　　　　　　
  関口 和彦, 工藤 慎治, 金 庚煥, 坂本 和彦, 熊谷貴美代, 飯島 明宏, 大谷 吉生
  第26回エアロゾル科学・技術研究討論会, Aug. 2009, [Domestic conference]
• Characterization of summertime submicron aerosols at Saitama, Japan, using an aerosol mass spectrometer and an annular denuder-filter pack system　　　　　　　　　　　　　　　
  S. Shimada, K. Enya, L. Bao, T. Takada, R. Ortiz, K. Sekiguchi, Q. Wang, K. Sakamoto
  Abstracts of the 11th International Conference on Atmospheric Sciences and Applications to Air Quality, Apr. 2009, [International conference]
• 超音波霧の空気浄化手法への応用－その１ 2成分溶液からの霧発生とその粒径分布　　　　　　　　　　　　　　　
  並木 則和,木部 貴弘,関口 和彦
  第27回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2009, [Domestic conference]
• 超音波霧の空気浄化手法への応用－その２ チタニア含有霧によるVOCガスの分解　　　　　　　　　　　　　　　
  関口 和彦,能代谷大介,坂本 和彦,並木 則和
  第27回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2009, [Domestic conference]
• Gaseous and particulate concentrations of water-soluble organic acids at a suburban site in Saitama, Japan　　　　　　　　　　　　　　　
  L. Bao, K. Sekiguchi, Q. Wang, R. Oritz, K. Sakamoto
  Abstracts of the 11th International Conference on Atmospheric Sciences and Applications to Air Quality, Apr. 2009, [International conference]
• 超音波霧化法による懸濁液からの超微粒子の発生　　　　　　　　　　　　　　　
  並木 則和,木部 貴弘,関口 和彦,井川 誠司
  化学工学会第74年会, Mar. 2009, [Domestic conference]
• 光触媒含有霧を用いたVOC分解における物質種の影響　　　　　　　　　　　　　　　
  関口 和彦,能代谷大介,坂本 和彦,並木 則和
  第17回ソノケミストリー討論会, Dec. 2008, [Domestic conference]
• 2008年東京郊外(首都大)におけるN2O5実大気測定　　　　　　　　　　　　　　　
  木村 嘉克,中嶋 吉弘,Suthawaree Jeeranut,田島 洋介,宮崎 洸治,岡崎 創,山崎 晃司,長田 拓也,加藤 俊吾,梶井 克純,高田 智至,下 紳郎,窪田 勉,Ricardo Ortiz Ramirez,塩谷 健二,関口 和彦,坂本 和彦
  第14回大気化学討論会, Oct. 2008, [Domestic conference]
• そのクロスメディア (気圏、水圏、地圏) 環境への関わり　　　　　　　　　　　　　　　
  塩谷 健二,関口 和彦,坂本 和彦
  第49回大気環境学会年会, Sep. 2008, [Domestic conference]
• 2007年夏季関東における微小粒子広域観測とモデリング(2)－AMSを用いた高時間分解粒子組成観測－　　　　　　　　　　　　　　　
  高見 昭憲,長谷川就一,小林 伸治,高田 智至,下 紳郎,下野 彰夫,疋田 利秀,速水 洋,窪田 勉,関口 和彦,坂本 和彦,萩野 浩之
  第49回大気環境学会年会, Sep. 2008, [Domestic conference]
• 2007年夏季関東における微小粒子広域観測とモデリング(3)－AMSを用いた騎西ならびに前橋での粒子成分挙動の解析－　　　　　　　　　　　　　　　
  窪田 勉,関口 和彦,坂本 和彦,萩野 浩之,高見 昭憲,長谷川就一,小林 伸治,高田 智至,下 紳郎,下野 彰夫,疋田 利秀,速水 洋
  第49回大気環境学会年会, Sep. 2008, [Domestic conference]
• 2007年夏季関東における微小粒子広域観測とモデリング(8)－広域大気シミュレーションによる再現性検証－　　　　　　　　　　　　　　　
  茶谷 聡,下 紳郎,高田 智至,森川多津子,米持 真一,梅沢 夏実,窪田 勉,関口 和彦,坂本 和彦,速水 洋,長谷川就一,小林 伸治
  第49回大気環境学会年会, Sep. 2008, [Domestic conference]
• 2007年夏季関東における微小粒子広域観測とモデリング(4)－炭素成分の時間的・空間的挙動－解析－　　　　　　　　　　　　　　　
  長谷川就一,高見 昭憲,窪田 勉,関口 和彦,坂本 和彦,高田 智至,下 紳郎,下野 彰夫,疋田 利秀,米持 真一,梅沢 夏実,飯島 明宏,熊谷貴美代,高橋 克行,速水 洋
  第49回大気環境学会年会, Sep. 2008, [Domestic conference]
• 2007年夏季関東における微小粒子広域観測とモデリング(7)－3次元モデルで計算される有機炭素収支－　　　　　　　　　　　　　　　
  森野 悠,大原 利眞,長谷川就一,高見 昭憲,窪田 勉,関口 和彦,坂本 和彦,小林 伸治,田邊 潔
  第49回大気環境学会年会, Sep. 2008, [Domestic conference]
• 2008年スギ花粉飛散期における都市部道路端でのSPM中のイオン及び炭素成分の特性　　　　　　　　　　　　　　　
  王 青躍,胡 舜尭,栗原 幸大,龔 秀民,仲村 慎一,関口 和彦,中島 大介
  第49回大気環境学会年会, Sep. 2008, [Domestic conference]
• 高熱流束マイクロプラズマの空気浄化手法への応用　　　　　　　　　　　　　　　
  関口 和彦
  第25回エアロゾル科学・技術研究討論会, Aug. 2008, [Domestic conference]
• アジア地域の都市大気中ナノ粒子濃度と多環芳香族化合物の特性　　　　　　　　　　　　　　　
  白 雲鶴,古内 正美,大谷 吉生,塚脇 真二,Hang P.,Sieng S.,Limpaseni W.,Takasakul P.,関口 和彦,田島奈穂子
  第25回エアロゾル科学・技術研究討論会, Aug. 2008, [Domestic conference]
• Chemical characterization of water-soluble organic acids in size-segregated particles at roadside and suburban sites　　　　　　　　　　　　　　　
  Bao L., Sekiguchi K., Wang Q. and Sakamoto K.
  第25回エアロゾル科学・技術研究討論会, Aug. 2008, [Domestic conference]
• 新規超微小粒子捕集システム開発のための多重管デニューダー性能評価　　　　　　　　　　　　　　　
  関口 和彦,金 庚煥,坂本 和彦,大谷 吉生,瀬戸 章文,古内 正美,吉川 文恵,榎原 研正,平澤 誠一,田島奈穂子,加藤 孝晴
  第25回エアロゾル科学・技術研究討論会－国際シンポジウム2008, Aug. 2008, [International conference]
• 道路近傍で採取されたナノ粒子中の多環芳香族化合物の特性　　　　　　　　　　　　　　　
  白 雲鶴,古内 正美,大谷 吉生,畑 光彦,中村早紀子,福本 武秀,関口 和彦,田島奈穂子
  第25回エアロゾル科学・技術研究討論会－国際シンポジウム2008, Aug. 2008, [International conference]
• 都市部および郊外における超微小粒子成分の観測　　　　　　　　　　　　　　　
  関口 和彦,工藤 慎治,安原 正博,坂本 和彦,大谷 吉生
  第25回エアロゾル科学・技術研究討論会－国際シンポジウム2008, Aug. 2008, [International conference]
• マイクロバブル‐液相系光触媒を用いた液体中有機物質分解に関する研究　　　　　　　　　　　　　　　
  安井 文男,田村 一,関口 和彦,守永 若菜
  日本混相流学会年会講演会2008講演論文集, Aug. 2008, [Domestic conference]
• 光触媒含有霧から生成する反応活性種を用いた有機汚染ガスの分解とその物性影響　　　　　　　　　　　　　　　
  関口 和彦,能代谷大介,坂本 和彦
  第26回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2008, [Domestic conference]
• 高熱流束マイクロプラズマの空気浄化手法への応用に関する基礎検討　　　　　　　　　　　　　　　
  関口 和彦,長澤 一真,坂本 和彦,長谷川靖洋
  第26回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2008, [Domestic conference]
• Influence of nitric acid and ammonia on heterogeneous uptake and oxidation of sulfur dioxide on yellow sand particles　　　　　　　　　　　　　　　
  Sakamoto K., Kaneko T., Horita Y., Tonegawa Y., Takada H., Sorimachi A., Sekiguchi K., Wang Q. and Ishihara H.
  Abstracts of European Geosciences Union General Assembly 2008, Apr. 2008
• Application of ultrasound to BDF synthesis and purification process　　　　　　　　　　　　　　　
  Sekiguchi K., Mogi F., Kurokawa H., Wang Q. and Sakamoto K.
  Abstracts of International Symposium on Sonochemistry and Sonoprocessing 2007- New Horizons in Sonochemistry and Sonoprocessing -, Dec. 2007
• Photocatalytic degradation and capture of organic gases in an ultrasonic mist and their sonophotocatalytic mineralization in the liquid phase　　　　　　　　　　　　　　　
  Sekiguchi K., Morinaga W., Yamamoto K., Sasaki C. and Sakamoto K.
  Abstracts of International Symposium on Sonochemistry and Sonoprocessing 2007- New Horizons in Sonochemistry and Sonoprocessing -, Dec. 2007
• Influence of nitrogen oxides on heterogeneous uptake and oxidation of sulfur dioxide on yellow sand particles　　　　　　　　　　　　　　　
  Horita Y., Sorimachi A., Takada H., Sekiguchi K., Wang Q. Y., Ishihara H., Nishikawa M. and Sakamoto K.
  Proceedings of the 2007 International Symposium on Environmental Science and Technology (2007 ISEST), Nov. 2007, [International conference]
• Measurements of atmospheric bifunctional carbonyls at rural and suburban areas　　　　　　　　　　　　　　　
  Ortiz R., Sekiguchi K. and Sakamoto K.
  Proceedings of the 2007 International Symposium on Environmental Science and Technology (2007 ISEST), Nov. 2007, [International conference]
• Measurement of polycyclic aromatic hydrocarbons in bio-diesel exhaust particles　　　　　　　　　　　　　　　
  Shirai T., Mogi F., Sekiguchi K., Wang Q. Y., Kurokawa H., Yoshimura Y. and Sakamoto K.
  Proceedings of the 2007 International Symposium on Environmental Science and Technology (2007 ISEST), Nov. 2007, [International conference]
• 廃木材と鶏糞の炭化処理昇温速度およびその炭化物着火特性に関する研究　　　　　　　　　　　　　　　
  王 青躍,飯島 敦史,アパル パタル,関口 和彦,坂本 和彦,黒川 秀樹,中島 大介
  第18回廃棄物学会研究発表会, Nov. 2007
• Chemical Composition of Atmospheric Aerosols in the General Environment and Around a Trunk Road in Urban and Suburban Areas in Japan　　　　　　　　　　　　　　　
  Sakamoto K, Sakaguchi T., Jiang Z. W., Naser T. M., Sekiguchi K., Wang Q. Y. and Takahashi K.
  The 2007 Environmental Societies Joint Conference 2007. 5. 3 Korea-Japan Special Symposium on Fine Particles, Oct. 2007
• 高層ビル上層階における超微小粒子の観測　　　　　　　　　　　　　　　
  関口 和彦,工藤 慎治,坂本 和彦
  第48回大気環境学会年会講演要旨集, Sep. 2007
• 粒子状物質の粒径別内気外気相関からみた人間活動の影響　　　　　　　　　　　　　　　
  関口 和彦,石川 信幸,鈴木 宏保,坂本 和彦
  第24回エアロゾル科学・技術研究討論会, Aug. 2007
• 都市部超微小粒子の高度別観測　　　　　　　　　　　　　　　
  関口 和彦,工藤 慎治,安原 正博,坂本 和彦,大谷 吉生
  第24回エアロゾル科学・技術研究討論会, Aug. 2007
• 超音波霧と光触媒による有機汚染ガスの処理　　　　　　　　　　　　　　　
  関口 和彦,山本 圭介,能代谷大介,坂本 和彦
  第24回エアロゾル科学・技術研究討論会, Aug. 2007
• Atmospheric concentration of selected polycyclic aromatic hydrocarbons in PM2.5 at a roadside and an urban background area in Saitama city, Japan　　　　　　　　　　　　　　　
  タレック モハメド ナセル, 吉村 有史, 関口 和彦, 王 青躍, 坂本 和彦
  第24回エアロゾル科学・技術研究討論会, Aug. 2007
• 都市近郊大気での微小粒子組成に対する発生源の影響調査　　　　　　　　　　　　　　　
  窪田 勉,萩野 浩之,関口 和彦,坂本 和彦
  第24回エアロゾル科学・技術研究討論会, Aug. 2007
• Measurement of fine particles with an aerosol mass spectrometer at roadside and background location　　　　　　　　　　　　　　　
  Kubota T., Sekiguchi K. and Sakamoto K.
  Abstracts of the 5th Asian Aerosol Conference, Aug. 2007
• Sampling and analysis of atmospheric ultrafine particles at the upper and lower floors of a high-rise building in the urban area　　　　　　　　　　　　　　　
  Sekiguchi K., Kudo S., Yasuhara M., Otani Y. and Sakamoto K.
  Abstracts of the 5th Asian Aerosol Conference, Aug. 2007
• Indoor/outdoor relationships and carbonaceous components of ultrafine particles　　　　　　　　　　　　　　　
  Sekiguchi K., Ishikawa N., Suzuki H., Suzuki T., Fujii S. and Sakamoto K.
  Abstracts of the 5th Asian Aerosol Conference, Aug. 2007
• Photocatalytic degradation of ethtlene using ozone-producing UV lamp with TiO2 catalyst　　　　　　　　　　　　　　　
  Chang K. L., Sekiguchi K., Sakamoto K. and Chou M. S.
  Abstracts of the 5th Asian Aerosol Conference, Aug. 2007
• 静電式超微小粒子濃縮装置を用いた室内炭素成分捕集計測の可能性　　　　　　　　　　　　　　　
  藤井 修二,関口 和彦,鈴木 智彰
  第24回エアロゾル科学・技術研究討論会, Aug. 2007
• The effect of humidify to the formation and growth of secondary organic aerosol at photooxidation in smog chamber　　　　　　　　　　　　　　　
  Enya K., Sekiguchi K. and Sakamoto K.
  Abstracts of the 5th Asian Aerosol Conference, Aug. 2007
• Chemical Composition of Atmospheric Aerosols in the General Environment and Around a Trunk Road in Urban and Suburban Areas　　　　　　　　　　　　　　　
  K. Sakamoto, T. Sakaguchi, Z. W. Jiang, T. M. Naser, K. Sekiguchi, Q. Y. Wang, K. Takahashi
  The 2007 Environmental Societies Joint Conference ―2007. 5. 3― Korea-Japan Special Symposium on Fine Particles, May 2007, [Invited], [International conference]
• 触媒含有霧を利用した有機汚染ガスの光触媒分解に関する研究　　　　　　　　　　　　　　　
  関口 和彦,山本 圭介,坂本 和彦
  第25回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2007
• 水中気泡反応場における有機汚染ガスの分解処理に関する研究　　　　　　　　　　　　　　　
  関口 和彦,守永 若菜,木村 敏明,坂本 和彦
  第25回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2007
• チタニア含有液滴を用いるVOCの光分解　　　　　　　　　　　　　　　
  関口 和彦
  超音波霧化シンポジウム, Mar. 2007, [Invited], [Domestic conference]
• Improvement in gasification of biomass briquette acompanying with effective use of waste coal　　　　　　　　　　　　　　　
  Wang Q. Y., Shukuzaki N., Sekiguchi K., Sakamoto K., Kurokawa H., Akibayashi T. and Yamada T.
  Proceedings of Renewable Energy 2006, Oct. 2006, [International conference]
• Study on char-biomass briquette of pyrolyzed materials from industrial organic wastes　　　　　　　　　　　　　　　
  Wang Q. Y., Endo H., Shukuzaki N., Sekiguchi K., Sakamoto K., Kurokawa H., Nakaya Y. and Akibayashi T.
  Proceedings of Renewable Energy 2006, Oct. 2006, [International conference]
• 光触媒含有霧を利用したガス状汚染物質の分解に対する諸因子影響の調査　　　　　　　　　　　　　　　
  関口 和彦,山本 圭介,坂本 和彦
  第15回ソノケミストリー討論会, Oct. 2006
• Measurement of PM2.5 and Ultrafine Particles around Roadside in Suburban Area　　　　　　　　　　　　　　　
  Sekiguchi K., Yasuhara M. Ishikawa N., Namiki N., Otani Y. and Sakamoto K.
  Abstracts of the 7th International Aerosol Conference, Sep. 2006
• Bifunctional carbonyls distribution in gaseous and particulate phases in South-Kanto, Japan　　　　　　　　　　　　　　　
  Ortiz R., Sekiguchi K. and Sakamoto K.
  Abstracts of the 15th IUPPA regional conference; Air pollution and environmental health, Sep. 2006
• Photocatalysis of gaseous pollutants by ultrasonic mist including TiO2 particles　　　　　　　　　　　　　　　
  Sekiguchi K., Yamamoto K. and Sakamoto K.
  Abstracts of the 7th International Aerosol Conference, Sep. 2006
• インパクタフィルタ分級捕集システムを用いた道路近傍超微小粒子の炭素成分分析　　　　　　　　　　　　　　　
  関口 和彦,安原 正博,石川 信幸,坂本 和彦
  第47回大気環境学会年会, Sep. 2006
• 光と反応活性種を用いた粒子相汚染物質の分解処理 粒子内部への拡散を利用した汚染物質の分解　　　　　　　　　　　　　　　
  関口 和彦,上田 武俊,山本 圭介,坂本 和彦
  第23回エアロゾル科学・技術研究討論会, Aug. 2006
• 光と反応活性種を用いた粒子相汚染物質の分解処理　　　　　　　　　　　　　　　
  関口 和彦,上田 武俊,坂本 和彦
  第23回エアロゾル科学・技術研究討論会, Aug. 2006
• フィルター捕集分析とリアルタイム測定による微小粒子中の成分濃度比較　　　　　　　　　　　　　　　
  窪田 勉,吉田 直樹,関口 和彦,坂本 和彦
  第23回エアロゾル科学・技術研究討論会, Aug. 2006
• 道路近傍における大気中超微小粒子の分級捕集とその組成分析　　　　　　　　　　　　　　　
  関口 和彦,安原 正博,坂本 和彦,大谷 吉生
  第23回エアロゾル科学・技術研究討論会, Aug. 2006
• 南関東地域の夏季における汚染気塊の移流と有機エアロゾルの二次生成　　　　　　　　　　　　　　　
  坂本 和彦,吉田 直樹,関口 和彦,王 青躍
  第23回エアロゾル科学・技術研究討論会, Aug. 2006
• Bifunctional carbonyls distribution in gaseous and particulate phases at an urban and a suburban area　　　　　　　　　　　　　　　
  Ortiz R., Sekiguchi K. and Sakamoto K.
  Proceedings of the 8th International Symposium on Building and Urban Environmental Engineering, BUEE2006, Jul. 2006, [International conference]
• Size distributions and chemical components of particulate matter from soil and road dust　　　　　　　　　　　　　　　
  Jiang Z., Wang Q., Sekiguchi K., Naser T. M. and Sakamoto K.
  Proceedings of the 8th International Symposium on Building and Urban Environmental Engineering, BUEE2006, Jul. 2006, [International conference]
• The impact of diesel exhaust particles on the chemical compositions of PM2.5 and PM10 at roadside and urban bachground areas　　　　　　　　　　　　　　　
  Naser T. M., Jiang Z., Sekiguchi K., Wang Q. and Sakamoto K.
  Proceedings of the 8th International Symposium on Building and Urban Environmental Engineering, BUEE2006, Jul. 2006, [International conference]
• 酵素 UV法によるバイオディーゼル燃料中のグリセリンの定量　　　　　　　　　　　　　　　
  黒川 秀樹,宮川聡一郎,皆川 智美,関口 和彦,王 青躍,坂本 和彦,三浦 弘
  石油学会第55回研究発表会, May 2006
• 超音波霧化を利用した有機汚染ガスの光触媒分解に関する基礎研究　　　　　　　　　　　　　　　
  関口 和彦,山本 圭介,坂本 和彦
  第24回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2006
• 慣性分離による超微小粒子分級用インパクタフィルタの開発(1) 基本性能の評価と構造の最適化　　　　　　　　　　　　　　　
  嶋田いつか,坂野 健夫,李 相権,並木 則和,大谷 吉生,関口 和彦
  第24回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2006
• 慣性分離による超微小粒子分級用インパクタフィルタの開発(2) 大気中超微小粒子の分級捕集と炭素成分からみた性能評価　　　　　　　　　　　　　　　
  関口 和彦,石川 伸幸,坂本 和彦,並木 則和,大谷 吉生
  第24回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2006
• Water-soluble organic nitrogen and water-soluble organic carbon in precipitation and fine particles over a suburban area　　　　　　　　　　　　　　　
  Segovia E., Yoshida N., Sekiguchi K., Wang Q. Y. and Sakamoto K.
  Abstracts of the 1st iLEAPS Science Conference, Jan. 2006, [International conference]
• 光触媒と超音波を併用した有機物の分解 中間生成物の分解速度からみた併用効果　　　　　　　　　　　　　　　
  関口 和彦,佐々木智恵,坂本 和彦
  第14回ソノケミストリー討論会講演論文集, Oct. 2005
• 超音波霧化を利用したガス状汚染物質の光触媒分解に関する研究　　　　　　　　　　　　　　　
  関口 和彦,山本 圭介,坂本 和彦
  第14回ソノケミストリー討論会講演論文集, Oct. 2005
• Removal of NOx and VOCs by short-wavelength UV and TiO2　　　　　　　　　　　　　　　
  Jeong J., Sekiguchi K., An H., Lee Y. and Sakamoto K.
  Proceedings of the 10th International Conference on Indoor Air Quality and Climate; Indoor Air 2005, Sep. 2005, [International conference]
• 土壌及び道路粉塵に由来する粒子状物質の粒径別化学組成について　　　　　　　　　　　　　　　
  姜 兆武,王 青躍,関口 和彦,坂本 和彦
  第46回大気環境学会年会講演要旨集, Sep. 2005
• Investigation on variations of suspended particulates in urban area of Japan by the regulation for diesel automobile exhaust　　　　　　　　　　　　　　　
  Jiang Z. W., Wang Q. Y., Sekiguchi K. and Sakamoto K.
  Abstracts of the 16th Regional Conference of Clean Air and Environment in Asian Pacific Area, Aug. 2005
• 静電濃縮超微小粒子捕集装置(ECUFP)を用いた大気エアロゾル中の多環芳香族炭化水素類の評価　　　　　　　　　　　　　　　
  村上 雅志,竹田 菊男,藤本 英治,木村 義孝,坂本 和彦,関口 和彦,大谷 吉生,並木 則和,藤井 修二,鍵 直樹,福嶋 信彦,田島奈穂子,根津 豊彦,吉村 有史
  第22回エアロゾル科学・技術研究討論会, Jul. 2005
• UFPCを用いた道路近傍の建物室内外における超微小粒子の測定　　　　　　　　　　　　　　　
  関口 和彦,鈴木 宏保,安原 正博,坂本 和彦,根津 豊彦,吉村 有史
  第22回エアロゾル科学・技術研究討論会, Jul. 2005
• 静電濃縮超微小粒子捕集装置(ECUFP)を用いた大気中超微小粒子の水溶性イオン成分評価　　　　　　　　　　　　　　　
  村上 雅志,竹田 菊男,藤本 英治,木村 義孝,坂本 和彦,関口 和彦,大谷 吉生,並木 則和,藤井 修二,鍵 直樹,福嶋 信彦,田島奈穂子,根津 豊彦,吉村 有史
  第22回エアロゾル科学・技術研究討論会, Jul. 2005
• 超微小粒子(UFP)の屋内外数濃度測定と組成分析のためのUFP濃度装置の開発　　　　　　　　　　　　　　　
  関口 和彦
  第1回日本エアロゾル学会若手会講演会～世代を超えた知識の共有とエアロゾル科学の新たな展開～, Jul. 2005, [Invited], [Domestic conference]
• 都市部から郊外における大気中OC, ECおよびWSOCの挙動　　　　　　　　　　　　　　　
  吉田 直樹,寺嶋 和也,萩野 浩之,関口 和彦,坂本 和彦
  第22回エアロゾル科学・技術研究討論会, Jul. 2005
• 水 二酸化チタン懸濁液を反応場としたガス状汚染物質の分解処理技術に関する研究　　　　　　　　　　　　　　　
  関口 和彦,木村 敏明,鄭 柱泳,坂本 和彦
  第23回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2005
• 光と反応活性種を用いた粒子相汚染物質の分解処理手法に関する研究　　　　　　　　　　　　　　　
  関口 和彦,上田 武俊,坂本 和彦
  第23回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2005
• 各種荷電手法を用いた超微小粒子荷電時における粒子組成変化に関する研究　　　　　　　　　　　　　　　
  坂本 和彦,関口 和彦,小前 草太,姜 庚尾
  第23回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2005
• 光イオン化法を用いた超微小粒子用荷電濃縮捕集システムの構築　　　　　　　　　　　　　　　
  並木 則和,大谷 吉生,田島奈穂子,鍵 直樹,藤井 修二,関口 和彦,坂本 和彦
  第23回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2005
• 光イオン化法を用いた超微小粒子用荷電濃縮装置の開発　　　　　　　　　　　　　　　
  並木 則和,林 敦史,大谷 吉生,田島奈穂子,福嶋 信彦,鍵 直樹,藤井 修二,関口 和彦,坂本 和彦
  化学工学会第70年会, Mar. 2005
• 光触媒を併用した水中有機汚染物質の超音波分解 分解率に与える触媒量と周波数の影響　　　　　　　　　　　　　　　
  関口 和彦,佐々木智恵、坂本 和彦
  第13回ソノケミストリー討論会講演論文集, Nov. 2004
• フッ素系液体(FC)／水エマルジョン溶媒中におけるトルエンの超音波／光触媒併用分解　　　　　　　　　　　　　　　
  関口 和彦,山本 圭介,鈴木健太郎、坂本 和彦
  第13回ソノケミストリー討論会講演論文集, Nov. 2004
• 道路端と一般大気における超微小粒子の測定 超微小粒子数濃度とPM2.5中成分濃度との相関　　　　　　　　　　　　　　　
  安原 正博,鈴木 宏保,関口 和彦,坂本 和彦
  大気環境化学若手の会, Oct. 2004
• 短波長紫外光を用いた光化学および光触媒反応による有機汚染ガスの高効率分解　　　　　　　　　　　　　　　
  関口 和彦,鄭 柱泳,坂本 和彦
  大気環境化学若手の会, Oct. 2004
• フッ素系液体／エマルジョン溶媒を用いた循環型ガス吸収 液相連続処理プロセスの構築　　　　　　　　　　　　　　　
  山本 圭介,鈴木健太郎、関口 和彦,坂本 和彦
  大気環境化学若手の会, Oct. 2004
• 大都市道路近傍でのPM2.5中成分と超微小粒子の夏期および冬期における濃度相関　　　　　　　　　　　　　　　
  関口 和彦,根津 豊彦,吉村 有史,坂本 和彦
  第45回大気環境学会年会講演要旨集, Oct. 2004
• 黄砂粒子上での硫黄酸化物の酸化反応における窒素酸化物の影響　　　　　　　　　　　　　　　
  堀田 陽一,反町 篤行,関口 和彦,王 青躍,石原日出一,西川 雅高,坂本 和彦
  第45回大気環境学会年会講演要旨集, Oct. 2004
• 有機成分の炭化によるEC定量への影響　　　　　　　　　　　　　　　
  寺嶋 和也,関口 和彦,姜 兆武,坂口 智洋,梅沢 夏実,米持 真一,坂本 和彦
  第45回大気環境学会年会講演要旨集, Oct. 2004
• 埼玉県道路近傍における大気浮遊粒子状物質の挙動に関する研究　　　　　　　　　　　　　　　
  姜 兆武,王 青躍,関口 和彦,坂本 和彦
  第45回大気環境学会年会講演要旨集, Oct. 2004
• 都市部および郊外におけるPM2.5および超微小粒子の測定　　　　　　　　　　　　　　　
  関口 和彦,坂本 和彦,根津 豊彦,吉村 有史
  第21回エアロゾル科学・技術研究討論会, Aug. 2004
• 低温条件下における黄砂粒子上への二酸化硫黄の沈着　　　　　　　　　　　　　　　
  高田 尚枝,佐々木大樹,反町 篤行,石原日出一,関口 和彦,王 青躍,坂本 和彦
  第21回エアロゾル科学・技術研究討論会, Aug. 2004
• Photodegradation of VOCs by TiO2 under UV-C Irradiation and Water-Solubility of Gaseous/Particulate Intermediates　　　　　　　　　　　　　　　
  Jeong J. Y., Sekiguchi K. and Sakamoto K.
  Proceedings of the 16th International Conference on Nucleation and Atmospheric Aerosols, Jul. 2004, [International conference]
• Field Evaluation of a Newly Developed Condensation Nuclei/Optical Particle Counter for Size Dividing Monitoring of PM2.5 and Ultra-Fine Particles in Atmosphere　　　　　　　　　　　　　　　
  Sekiguchi K., Suzuki H., Nezu T., Hirano M., Yoshimura Y., Koyama H., Fukushima N., Otake T. and Sakamoto K.
  Proceedings of the 16th International Conference on Nucleation and Atmospheric Aerosols, Jul. 2004, [International conference]
• Differences on EC and OC Concentrations Measured by Thermal-Optical Method　　　　　　　　　　　　　　　
  Terashima K., Hagino H., Sekiguchi K., Ishihara H., Umezawa N., Yonemochi S., Matsumoto R., Mizohata A. and Sakamoto K.
  Proceedings of the 16th International Conference on Nucleation and Atmospheric Aerosols, Jul. 2004, [International conference]
• Ambient Air Measurements of Six Bifunctional Carbonyls in a Suburban Area　　　　　　　　　　　　　　　
  Ortiz R., Hagino H., Wang Q., Sekiguchi K. and Sakamoto K.
  Proceedings of the 16th International Conference on Nucleation and Atmospheric Aerosols, Jul. 2004, [International conference]
• Heterogeneous Uptake and Oxidation of Sulfur Dioxide on China Loess　　　　　　　　　　　　　　　
  Horita Y., Takada H., Sorimachi A., Sekiguchi K., Wang Q., Ishihara H., Nishikawa M. and Sakamoto K.
  Proceedings of the 16th International Conference on Nucleation and Atmospheric Aerosols, Jul. 2004, [International conference]
• 短波長UV光/TiO2とウェットスクラバーを組み合わせたVOCs除去システムの開発　　　　　　　　　　　　　　　
  鄭 柱泳,関口 和彦,坂本 和彦
  第22回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2004
• 低温条件下におけるガス 液相捕集光触媒分解技術に関する研究　　　　　　　　　　　　　　　
  関口 和彦,木村 敏明,坂本 和彦
  第22回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2004
• 廃発泡スチロールとセメントからなる酸化チタン塗布吸音材を用いた大気汚染物質の除去　　　　　　　　　　　　　　　
  関口 和彦,上田 武俊,坂本 和彦,利根川義男,野村 公康
  第22回空気清浄とコンタミネーションコントロール研究大会予稿集, Apr. 2004
• Application of the Photocatalyst to Air Purification Technique Considering the Control of Decomposition Products　　　　　　　　　　　　　　　
  K. Sekiguchi
  Material of invitation and lecture at Environmental Seminar Series in Washington University in St. Louis, [Invited], [International conference]