Comparison of Atmospheric Monocarboxylic and Dicarboxylic Acids in Xi' an, China, for Source Apportionment of Organic Aerosols
Comparison of Atmospheric Monocarboxylic and Dicarboxylic Acids in Xi' an, China, for Source Apportionment of Organic Aerosols
复制标题
西安市大气一元羧酸和二元羧酸比较用于有机气溶胶的来源解析
DOI：
10.1007/s11270-020-04675-y
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Zhao Jingchan
中科院分区：
文献类型：
--
作者：
Wu Lingmin;Wei Liulin;Wang Gailing;Zhao Jingchan
To investigate the characteristic distributions and formation mechanism of the polar organic components in atmospheric aerosols, atmospheric particulates were simultaneously sampled at three typical sites in urban(U), suburban(S) and rural(R) of Xi’an in summer and winter. Organic compositions, including dicarboxylic acids (DCAs), monocarboxylic acids (MCAs) were emphatically analyzed to explore the seasonal, spatial, and other variations. The results showed that total concentrations of DCAs and MCAs in winter were higher than those in summer. Athough the total content of DCAs in PM10 in winter is lower than that of MCAs, the total concentration of DCAs in PM2.5 and PM10 in summer are higher than that of MCAs. The total concentration of DCAs in PM2.5 in winter and summer were 1878 ± 1425 ng/m3and 1334 ± 493 ng/m3, 1294 ± 943 ng/m3and 728 ± 477 ng/m3in PM10. While the total concentration of MCAs in PM2.5 in winter and summer were 1193 ± 1142 ng/m3and 541 ± 367 ng/m3, 1659 ± 1162 ng/m3and 492 ± 424 ng/m3in PM10. Urban subtotal concentrations of DCAs from PM2.5 were the highest, and mass of organic acids in sunny days were significantly lower than the hazy days. Strong correlations were observed among the DCAs with ambient oxidants and precursors. Moreover, DCAs concentrations were vulnerable to the environmental factors, such as light intensity and relative humidity. Comparisons demonstrated that MCAs mainly comes from coal combustion, vehicle exhaust and other primary emissions, while the secondary photochemistry and liquid phase oxidation are the main sources of DCAs.
