title: Direct detection of isoprene photooxidation products by using synchrotron radiation photoionization mass spectrometry.
abstract: We report the combination of a vacuum ultraviolet photoionization mass spectrometer, operating on the basis of synchrotron radiation, with an environmental reaction smog chamber for the first time. The gas- and pseudo-particle-phase products of OH-initiated isoprene photooxidation reactions were measured on-line and off-line, respectively, by mass spectrometry. It was observed that aldehydes, methacrolein, methyl vinyl ketone, methelglyoxal, formic acid, and similar compounds are the predominant gas-phase photooxidation products, whereas some multifunctional carbonyls and acids mainly exist in the particle phase. This finding is reasonably consistent with results of studies conducted in other laboratories using different methods. The results indicate that synchrotron radiation photoionization mass spectrometry coupled with a smog chamber is a potentially powerful tool for the study of the mechanism of atmospheric oxidations and the formation of secondary organic aerosols.
authors.affiliation: Key Laboratory of Atmospheric Composition and Optical Radiation, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, 230031, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Pan
authors.forename: Changjin
authors.initials: C
authors.lastname: Hu
authors.forename: Zhenya
authors.initials: Z
authors.lastname: Wang
authors.forename: Yue
authors.initials: Y
authors.lastname: Cheng
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Zheng
authors.forename: Xuejun
authors.initials: X
authors.lastname: Gu
authors.forename: Weixiong
authors.initials: W
authors.lastname: Zhao
authors.forename: Weijun
authors.initials: W
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Fuyi
authors.initials: F
authors.lastname: Liu
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Shan
authors.forename: Liusi
authors.initials: L
authors.lastname: Sheng