近年来SO2在气溶胶表面的非均相反应被认为是大气污染期间硫酸盐的一种重要来源。本文在烟雾箱中研究了气溶胶水中锰离子和铁离子催化氧化SO2的反应动力学。得到了气溶胶水中锰离子催化氧化SO2反应的动力学，发现与本体水不同，锰离子在离子强度很高的气溶胶水中催化氧化SO2的反应速率比同等条件下本体水中速率提高了2个数量级，而铁离子离子在颗粒水中并没有表现出催化氧化SO2的性质。确定气溶胶水中锰离子和铁离子协同催化氧化SO2作用有限。一般约20%的SO2可通过非均相反应氧化，本研究进一步确定了非均相反应中的48% - 86%的硫酸盐来自气溶胶水中锰离子和铁离子催化氧化。该研究成果已经发表在Atmospheric Environment上。
• Catalytic oxidation of SO2 with low concentrations by metal ions has been studied in aerosol water.
• The Mn2+-catalytic oxidation rate of SO2 by O2 in aerosol water is 2 orders of magnitude higher than that in bulk water.
• Fe3+ and Mn2+ may only have a small synergistic catalysis in aerosol water, which is not as significant as in bulk water.
Zhang, H., Xu, Y., Jia, L., 2021. A chamber study of catalytic oxidation of SO2 by Mn2+/Fe3+ in aerosol water. Atmos. Environ. 245, 118019. https://doi.org/10.1016/j.atmosenv.2020.118019
The role of functional groups in the understanding of secondary organic aerosol formation mechanism from α-pinene
•The SOA is characterized by O–H groups in the OH channel and C=O groups in the O3 channel
•The nO−H/nC=O ratio is a good parameter in revealing the difference of SOA between the O3 and OH oxidation channels
•The SOA from OH channel is mainly formed by autoxidation of RO2 radicals
•Different structures of RO2 radicals are responsible for the difference functional group signatures of SOA
Molecular composition and sources of water-soluble organic aerosol in summer in Beijing
• Water-soluble organic aerosol was the major fraction of OA in summer in Beijing.
• SOA from regional and photochemical processing contributed dominantly to WSOA.
• A high diversity of CHO and CHOS molecular compounds in WSOA was observed.
• Formation of more organosulfates during polluted days than clean days in summer.
Qiu, Y., Xu, W., Jia, L., He, Y., Fu, P., Zhang, Q., Xie, Q., Hou, S., Xie, C., Xu, Y., Wang, Z., Worsnop, D.R., Sun, Y., 2020. Molecular composition and sources of water-soluble organic aerosol in summer in Beijing. Chemosphere 255, 126850.