The gas-phase organic compounds resulting from OH-initiated photooxidation of isoprene have been investigated on-line by VUV photoiortization mass spectrometry based on synchrotron radiation for the first time. The ph...The gas-phase organic compounds resulting from OH-initiated photooxidation of isoprene have been investigated on-line by VUV photoiortization mass spectrometry based on synchrotron radiation for the first time. The photoionization efficiency curves of the corresponding gaseous products as well as the chosen standards have been deduced by gating the interested peaks in the photoionization mass spectra while scanning the photon energy simultaneously, which permits the identification of the pivotal gaseous products of the photooxidation of isoprene, such as formaldehyde (10.84 eV), formic acid (11.38 eV), acetone (9.68 eV), glyoxal (9.84 eV), acetic acid (10.75 eV), methacrolein (9.91 eV), and methyl vinyl ketone (9.66 eV). Proposed reaction mechanisms leading to the formation of these key products were discussed, which were completely consistent with the previous works of different groups. The capability of synchrotron radiation photoionization mass spectrometry to directly identify the chemical composition of the gaseous products in a simulation chamber has been demonstrated, and its potential application in related studies of atmospheric oxidation of ambient volatile organic compounds is anticipated.展开更多
基金supported by the National Natural Science Foundation of China (No. 10979061,40975080)the Knowledge Innovation Foundation of Chinese Academy of Sciences (No. KJCX2-YW-N24)+1 种基金the Open Research Fund of Key Laboratory of Atmospheric Composition and Optical Radiation,Chinese Academy of Sciences (No. JJ10-04)the foundation of director of Anhui Institute of Optics and Fine Mechanics (No. Y03AG31147)
文摘The gas-phase organic compounds resulting from OH-initiated photooxidation of isoprene have been investigated on-line by VUV photoiortization mass spectrometry based on synchrotron radiation for the first time. The photoionization efficiency curves of the corresponding gaseous products as well as the chosen standards have been deduced by gating the interested peaks in the photoionization mass spectra while scanning the photon energy simultaneously, which permits the identification of the pivotal gaseous products of the photooxidation of isoprene, such as formaldehyde (10.84 eV), formic acid (11.38 eV), acetone (9.68 eV), glyoxal (9.84 eV), acetic acid (10.75 eV), methacrolein (9.91 eV), and methyl vinyl ketone (9.66 eV). Proposed reaction mechanisms leading to the formation of these key products were discussed, which were completely consistent with the previous works of different groups. The capability of synchrotron radiation photoionization mass spectrometry to directly identify the chemical composition of the gaseous products in a simulation chamber has been demonstrated, and its potential application in related studies of atmospheric oxidation of ambient volatile organic compounds is anticipated.