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オーラルセッション

第1日　5月15日（水）　17:20～17:40　D会場（202）

1D-O2-1720　　PDF

α-ピネンのオゾン酸化反応生成物のガス－粒子分配の決定のためのガス相・粒子相成分の同時・時間分解測定

(¹国環研・ ²JSPS特別研究員・ ³北大院地球環境・ ⁴京大院地球環境)
^o猪俣敏¹・ 谷本浩志¹・ 佐藤圭¹・ 藤谷雄二¹・ 森野悠¹・ 田邊潔¹・ Brown, Phil^1,2・ 矢嶋亮次³・ 坂本陽介⁴・ 廣川淳³

Atmospheric aerosols is thought to affect the global climate directly and indirectly as well as human health. Many volatile organic compounds undergo oxidation in the gas phase to yield semi-volatile organic compounds (SVOCs) that have vapor pressures sufficiently low that they are partitioned between the gas and aerosol phases, to contribute to the formation of secondary organic aerosols (SOAs). Quantification of the impacts of SOAs requires understanding their chemical composition and processes of formation. Because a systematic underestimation of simulated SOA production increases with air mass ageing, information about the partitioning of each SVOC between the gaseous and condensed phases is important for the description of SOA formation. We have developed a measurement system to identify SVOCs in both the gaseous and the aerosol phases using chemical ionization-mass spectrometry in order to estimate the gas-aerosol partitioning of each SVOC. In the system, SVOCs in both the gaseous and the aerosol phases are measured by the same technique, which enable us to determine the partitioning of each SVOC from the ratio of ion signals, without knowing the concentration of each SVOC. Time profiles of the SVOCs in both the gaseous and the aerosol phases, i.e. “real-time” SVOC partitioning, are discussed.