To investigate particle characteristics and find an effective measure to control severe parti-cle pollution,year-round observation of size-segregated inorganic aerosols was conducted in Beijing from January to December,2016.The sampled atmospheric particles all presented bimodal size distribution at four pollution levels(clear,slight pollution,moderate pollution and severe pollution),and peak values appeared at the size range of 0.7-2.1 μm and＞9.0 μm,respectively.As dominant particle compositions,NO3-,SO42-,and NH4+in four pollution levels all showed significant peaks in fine mode,especially at the size range of 1.1-2.1 μm.Secondary inorganic aerosols accounted for about 67.6％(36.3％(secondary sulfates)+31.3％(secondary nitrates))of the total sources of fine particles in urban Beijing.Severe pollution of fine particles was mainly caused by the air masses transported from nearby western and southern areas,which are industrial and densely populated region,respectively.Sensitivity tests further revealed that the control measures focusing on ammonium emission reduction was the most effective for particle pollution mitigation,and fine particles all showed nonlin-ear responses after reducing ammonium,nitrate,and sulfate concentrations,with the fitting curves of y =-120.8x-306.1x2+290.2x3,y =-43.5x-67.8x2,and y =-25.8x-110.4x2+7.6x3,re-spectively(y and x present fine particle mass variation(μg/m3)and concentration reduction ratio(CRR)/100(dimensionless)).Overall,our study presents useful information for under-standing the characteristics of atmospheric inorganic aerosols in urban Beijing,as well as offers policy makers with effective measure for mitigating particle pollution.

Xi Zhang;Jinhe Wang;Kai Zhang;Xiaona Shang;Masahide Aikawa;Guanhua Zhou;Jie Li;Huanhuan Li

State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;Resources and Environment Innovation Research Institute,School of Municipal and Environmental Engineering,Shandong Jianzhu University,Jinan 250101,China;Faculty of Environmental Engineering,The University of Kitakyushu,1-1 Hibikino,Wakamatsu,Kitakyushu,Fukuoka 808-0135,Japan;Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3),Department of Environmental Science and Engineering,Fudan University,Shanghai 200438,China;School of Instrumentation Science and Opto-electronics Engineering,Beihang University,Beijing 100191,China

环境科学学报（英文版）

[1]Xi Zhang;Jinhe Wang;Kai Zhang;Xiaona Shang;Masahide Aikawa;Guanhua Zhou;Jie Li;Huanhuan Li-.Year-round observation of atmospheric inorganic aerosols in urban Beijing:Size distribution,source analysis,and reduction mechanism)[J].环境科学学报（英文版）,2022(04):354-364

1x2+290,2x3,8x2,4x2+7,6x3

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