Atmospheric particulate pollution in China has attracted much public attention.Occasionally, the particle number concentration increases sharply in a short time period,which is defined as a "particulate matter ex...Atmospheric particulate pollution in China has attracted much public attention.Occasionally, the particle number concentration increases sharply in a short time period,which is defined as a "particulate matter explosive increase". Heavy particulate matter pollution not only reduces visibility but also has an adverse effect on human health. Hence,there is an urgent need to discover the causes of particulate matter explosive increase.During this campaign, the particle number concentration and free radicals were measured at a tall building on the campus of Lanzhou University of Technology. Additionally, we examined a series of chemicals to reproduce the observed particulate matter explosive increase in a smog chamber to determine its potential factors. Then, we analyzed the mechanism of particulate matter explosive increase in the presence of free radicals. We found that, among the potential inorganic and organic sources analyzed, a mixture of organic and SO_2 in the research region had a major effect on particulate matter explosive increase. Moreover, free radical oxidation has a large effect, especially in the formation of organic particulates.展开更多
基金supported by the National Key Research and Development Program of China(No.2016YFC0202900)the National Natural Science Foundation of China(Nos.21567015,21407072)+1 种基金Natural Science Foundation of Gansu Province(No.17JR5RA109)Gansu Provincial Party Committee Young Creative Talents(No.Ganzutongzi [2017]121)
文摘Atmospheric particulate pollution in China has attracted much public attention.Occasionally, the particle number concentration increases sharply in a short time period,which is defined as a "particulate matter explosive increase". Heavy particulate matter pollution not only reduces visibility but also has an adverse effect on human health. Hence,there is an urgent need to discover the causes of particulate matter explosive increase.During this campaign, the particle number concentration and free radicals were measured at a tall building on the campus of Lanzhou University of Technology. Additionally, we examined a series of chemicals to reproduce the observed particulate matter explosive increase in a smog chamber to determine its potential factors. Then, we analyzed the mechanism of particulate matter explosive increase in the presence of free radicals. We found that, among the potential inorganic and organic sources analyzed, a mixture of organic and SO_2 in the research region had a major effect on particulate matter explosive increase. Moreover, free radical oxidation has a large effect, especially in the formation of organic particulates.