The impact of relative humidity on aerosol composition and evolution processes during wintertime in Beijing, China
The impact of relative humidity on aerosol composition and evolution processes during wintertime in Beijing, China
复制标题
北京冬季相对湿度对气溶胶组成及演化过程的影响
DOI：
10.1016/j.atmosenv.2013.06.019
复制
发表时间：
2013-10-01
影响因子：
5
通讯作者：
Ge, Xinlei
中科院分区：
文献类型：
--
作者：
Sun, Yele;Wang, Zifa;Ge, Xinlei
利用Aerodyne气溶胶化学形态监测仪（ACSM）测量的非难熔亚微米气溶胶（NR-PM 1）物种与搭配的气态物种沿着，研究了相对湿度（RH）对中国北京冬季气溶胶组成和演变过程的影响。气溶胶物种表现出强烈的，但不同的RH之间的依赖性低和高RH水平。在低RH水平（50%）下，硫酸盐呈现甚至更快的增加速率，表明液态水对硫酸盐产生的显著影响。有机气溶胶（OA）组分的相对湿度依赖性也很不同。在OA组分中，煤燃烧OA（CCOA）的质量浓度和贡献作为RH的函数呈现出最大的增强。我们的研究结果阐明了重要的作用，液态水在气溶胶处理在RH水平升高，特别是影响硫酸盐和CCOA通过水相反应和气-粒分配与水的吸收，分别。据估计，水相处理可以贡献超过50%的二次无机物种的生产沿着增加的气溶胶粒子的酸度在雾期间。然而，它似乎没有显着提高二次有机气溶胶（SOA）的形成和OA的氧化程度。(C)2013爱思唯尔有限公司保留所有权利。
Non-refractory submicron aerosol (NR-PM1) species measured by an Aerodyne Aerosol Chemical Speciation Monitor (ACSM) along with collocated gaseous species are used to investigate the impacts of relative humidity (RH) on aerosol composition and evolution processes during wintertime in Beijing, China. Aerosol species exhibit strong, yet different RH dependence between low and high RH levels. At low RH levels (50%), sulfate presents an even faster increasing rate, indicating the significant impact of liquid water on sulfate production. The RH dependence of organic aerosol (OA) components is also quite different. Among OA components, coal combustion OA (CCOA) presents the largest enhancement in both mass concentration and contribution as a function of RH. Our results elucidate the important roles of liquid water in aerosol processing at elevated RH levels, in particular affecting sulfate and CCOA via aqueous-phase reaction and gas-particle partitioning associated with water uptake, respectively. It is estimated that aqueous-phase processing can contribute more than 50% of secondary inorganic species production along with an increase of aerosol particle acidity during the fog periods. However, it appears not to significantly enhance secondary organic aerosol (SOA) formation and the oxidation degree of OA. (C) 2013 Elsevier Ltd. All rights reserved.