Meng Jing-Jing, Hou Zhan-Fang, Zhang Er-Xun, Dong Jie, Liu Xiao-di, Xing Ji-Zhao, Liu Jia-Zhen
School of Environment and Planning, Liaocheng University, Liaocheng 252000, China.
State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China.
Huan Jing Ke Xue. 2017 Jul 8;38(7):2688-2697. doi: 10.13227/j.hjkx.201612182.
To identify the seasonal variation of dicarboxylic acids and related compounds in PM from Mt. Huangshan. PMsamples were collected during the summer and winter of 2015, which were then analyzed for dicarboxylic acids, ketocarboxylic acids, and -dicarbonyls. The results showed that oxalic acid(HOOC-COOH, C) was the dominant species in the summer and winter months, followed by malonic acid(HOOC-CH-COOH, C), and succinic acid[HOOC-(CH)-COOH, C], being consistent with that in other high-altitude regions. Most of the diacids were more abundant in the summer months than in the winter months, while adipic acid(C) and phahalic acid(Ph) were twice lower in the summer months, suggesting significant impact of anthropogenic pollution on the wintertime alpine atmosphere. Moreover, as major precursors of C, glyoxal(Gly) and methylglyoxal(mGly) were also lower in the summer months than in the winter months, which were opposite to those of the diacids, indicating that the mountain troposphere was more oxidative in the summer months than in the winter months. Principal component analysis(PCA) further revealed that the wintertime SOA in the Mt. Huangshan troposphere mostly originated from the anthropogenic pollutants from long-distance transport. Conversely, the summertime SOA mostly originated from the further oxidation of the mountainous biogenic sources. The AIM(Aerosol Inorganic Model) calculation results showed that the aqueous-phase C production was the primary mechanism of C formation in ambient aerosol and was driven by acid-catalyzed oxidation in summer.
为了确定黄山大气颗粒物中二元羧酸及相关化合物的季节变化。于2015年夏季和冬季采集了大气颗粒物样本，随后对其进行二元羧酸、酮羧酸和二羰基化合物的分析。结果表明，草酸（HOOC - COOH，C₂）在夏季和冬季月份都是主要成分，其次是丙二酸（HOOC - CH₂ - COOH，C₃）和琥珀酸[HOOC - (CH₂)₂ - COOH，C₄]，这与其他高海拔地区的情况一致。大多数二元酸在夏季月份的含量高于冬季月份，而己二酸（C₆）和邻苯二甲酸（Ph）在夏季月份的含量则低两倍，这表明人为污染对冬季高山大气有显著影响。此外，作为二次有机气溶胶（SOA）的主要前体，乙二醛（Gly）和甲基乙二醛（mGly）在夏季月份的含量也低于冬季月份，这与二元酸的情况相反，表明夏季山区对流层的氧化性强于冬季。主成分分析（PCA）进一步表明，黄山对流层冬季的SOA主要源自远距离传输的人为污染物。相反，夏季的SOA主要源自山区生物源的进一步氧化。气溶胶无机模型（AIM）计算结果表明，水相二次有机气溶胶生成是环境气溶胶中二次有机气溶胶形成的主要机制，并且在夏季由酸催化氧化驱动。
