DOI: 10.1016/j.atmosenv.2019.117223
论文题名: Composition analysis and formation pathway comparison of PM1 between two pollution episodes during February 2017 in Beijing, China
作者: Wang X. ; Wei W. ; Cheng S. ; Lv Z. ; Wang C. ; Niu Y.
刊名: Atmospheric Environment
ISSN: 1352-2310
出版年: 2020
卷: 223 语种: 英语
英文关键词: Atmospheric humidity
; Chemical speciation
; Oxidation
; Sulfur compounds
; Urban growth
; Atmospheric oxidation
; Average concentration
; Composition analysis
; Correlation coefficient
; Emission characteristics
; Negative correlation
; Sulfate/nitrate aged ratio
; WRF-CAMx
; Pollution
; ammonia
; nitrate
; nitrogen
; sulfate
; sulfur
; air quality
; air sampling
; atmospheric chemistry
; atmospheric pollution
; nitrate
; oxidation
; particle size
; particulate matter
; relative humidity
; speciation (chemistry)
; sulfate
; urban site
; aerosol
; air pollution
; air quality
; chemical composition
; China
; humidity
; meteorology
; particulate matter
; precursor
; priority journal
; species differentiation
; spring
; Beijing [China]
; China
学科: Atmospheric oxidation
; SNA
; Sulfate/nitrate aged ratio
; Sulphur oxidation ratio
; WRF-CAMx
中文摘要: SO42−, NO3− and NH4+ (SNA) are the major components of particulate matter in Beijing. In this study, hourly concentrations of SNA in PM1 were measured through an Aerodyne Aerosol Chemical Speciation Monitor (ACSM) at an urban site of Beijing, from February 3rd to 20th of 2017. The analysis of the differences between two pollution cases during the sampling period was further conducted. The results showed that the concentrations of NO3−, SO42− and NH4+ were 38.9 ± 10.5 μg/m3, 41.9 ± 22.2 μg/m3 and 31.3 ± 10.6 μg/m3 respectively in the first case. A negative correlation was reflected between the PM2.5 concentrations and the following two ratios: 1) NO3−/SO42−; 2) [NH4+] to ([NO3−]+2[SO42−]), with a correlation coefficient of −0.92 and −0.76 respectively. In the second case, the PM2.5 concentrations (proportions) were much higher, with values of 49.9 ± 17.0 μg/m3 (22.9 ± 7.7%), 42.3 ± 15.8 μg/m3 (20.3 ± 7.2%) and 33.1 ± 10.1 μg/m3 (15.3 ± 4.3%). In contrast. The two ratios were positively correlated with the PM2.5 concentrations, along with the correlation coefficient of 0.77 and 0.62. Hence, it is palpable that two pollution cases were sulfate and nitrate dominant in respective. The emission characteristics due to the Chinese Spring Festival before P1 might be a major cause. A modeling-monitoring coupled approach was established for the recognition of the secondary conversion of SO42− and NO3−. Results showed that sulfate/nitrate aged ratio (SAR and NAR) and sulphur oxidation ratio (SOR) in the second case were 0.48 ± 0.23, 0.22 ± 0.07 and 0.38 ± 0.23. They were all higher than those of the first case whose values were 0.32 ± 0.15, 0.18 ± 0.05 and 0.22 ± 0.12, which indicated that secondary conversion of precursors was enhanced in the second case. Although the OH concentrations were of no obvious difference in both cases, the average concentrations of H2O2, NO2 and the relative humidity were much higher in the second case, which provided sufficient conditions and time for the formation of SO42− and NO3−. © 2019 Elsevier Ltd Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/160568
Appears in Collections: 气候变化与战略
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作者单位: Key Laboratory of Beijing on Regional Air Pollution Control, Beijing University of Technology, Beijing, 100124, China
Recommended Citation:
Wang X.,Wei W.,Cheng S.,et al. Composition analysis and formation pathway comparison of PM1 between two pollution episodes during February 2017 in Beijing, China[J]. Atmospheric Environment,2020-01-01,223