乙二醛/硫酸铵水相二次有机气溶胶的光解研究  

Investigation of photolysis of glyoxal/ammonium sulfate aqueous secondary organic aerosol

作　　者：凡家福 喻远琴 顾学军[2] 唐小锋 FAN Jiafu;YU Yuanqin;GU Xuejun;TANG Xiaofeng(School of Physicals and Optoelectronics Engineering of Anhui University,Hefei 230601,China;Anhui Institute of Optics and Fine Mechanics Basic Science Physics Research Center,HFIPS,Chinese Academy of Sciences,Hefei 230031,China)

机构地区：[1]安徽大学物理与光电工程学院,安徽合肥230601 [2]中国科学院合肥物质科学研究院安徽光学精密机械研究所基础科学物理研究中心,安徽合肥230031

出　　处：《大气与环境光学学报》2025年第2期188-198,共11页Journal of Atmospheric and Environmental Optics

基　　金：国家自然科学基金(U1832184,21873002)。

摘　　要：水相反应对二次有机气溶胶的形成具有重要贡献,相关研究已成为大气气溶胶领域的研究热点之一。本文选择乙二醛/硫酸铵这一典型的水相反应体系作为研究对象,基于烟雾箱模拟反应系统,利用扫描电迁移粒径谱仪和真空紫外光电离质谱对该反应体系产生的二次有机气溶胶粒径和组分进行了测量,通过与暗反应条件下气溶胶分布特征的对比,探讨了紫外光辐照对不同相对湿度下乙二醛/硫酸铵水相二次有机气溶胶粒径和组分的影响机制。研究结果表明,紫外光能够诱导乙二醛/硫酸铵水相反应产物中咪唑、咪唑-2-甲醛等吸光物质发生光解,并且相对湿度能够影响其光解速率。在低、中相对湿度条件下,光解速率会随着相对湿度的增加而加快;而在高相对湿度条件下,光解现象几乎不发生。这些结果将有助于对大气二次有机气溶胶光学性质的全面认识,同时也为区域气候模型修正提供了重要参考。Aqueous reactions play an important role in the formation of secondary organic aerosols,and related research has become one of the hotspots in the field of atmospheric aerosols.The typical aqueous reaction system of glyoxal/ammonium sulfate was selected in this work.Based on a smog chamber simulation system,the particle size and composition of glyoxal/ammonium sulfate aqueous secondary organic aerosol were measured using a scanning mobility particle sizer and a vacuum ultraviolet photoionization time-of-flight mass spectrometer.By comparing with the reaction under dark conditions,the influence mechanism of ultraviolet light on the particle size and composition of glyoxal/ammonium sulfate aqueous secondary organic aerosol under different relative humidity was explored.It shows that ultraviolet light can induce the photolysis of light absorbing substances such as imidazole and imidazole-2-carboxaldehyde in the products of glyoxal/ammonium sulfate aqueous reaction,and relative humidity can affect their photolysis process.Under low and medium relative humidity conditions,the photolysis rate increases with the increase of relative humidity,while under high relative humidity,the photolysis phenomenon almost does not occur.These results are not only helpful to understand the optical properties of atmospheric secondary organic aerosols,but also provide an important reference for the modification of regional climate models.

关 键 词：乙二醛 硫酸铵 水相二次有机气溶胶 紫外光 粒径 

分 类 号：X51[环境科学与工程—环境工程]