- 第1日 5月15日（水） 17:20～17:40 D会場（202）
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.