用激光解吸附电离法对三甲苯生成二次有机气溶粒子的分析  

Analysis of secondary organic photooxidation products of trimethylbenzene using laser desorption/ionization method

作　　者：赵文武[1] 黄明强[1] 郝立庆[1] 郭晓勇[1] 顾学军[1] 王振亚[1] 方黎[1] 张为俊[1] 

机构地区：[1]中国科学院安徽光学精密机械研究所环境光谱学实验室,合肥230031

出　　处：《光学技术》2008年第4期544-546,共3页Optical Technique

基　　金：国家自然科学基金(20477043)

摘　　要：利用实验室烟雾腔,在不同的实验条件下研究了由羟基启动的三甲苯光氧化反应所产生的二次有机气溶胶,采用激光解吸附技术和气溶胶飞行时间质谱仪测量了产物的化学组分和粒子的粒径分布。结果表明:随着反应物三甲苯浓度的增加,所生成的二次有机气溶胶粒子数量增多;随着反应时间的延长,生成的粒子数目也增加,但是反应到一段时间后,检测到的粒子数目几乎保持不变;光照强度的增加有利于二次有机气溶胶的生成;通过对产物的化学成分分析,说明了在二次有机光氧化产物中粒子相产物主要是芳香的环保留产物、非芳香环保留产物和环断裂产物。The secondary organic aerosol（SOA）products from photooxidation of the aromatic hydrocarbon trimethylhenzene（TMB）are investigated.The experiments are conducted in a home-made smog chamber with several condations.The size and molecular composition of individual secondary organic aerosol（SOA）can be detected using laser desorption/ionization technique and a home-made aerosol time-of-flight mass spectrometer（ATOFMS）.The number of SOA particles increases with increasing the concentration of TMB.As the prolong of reaction time,the sum of SOA particles is also increased.After a certain reaction time,concentration of SOA particles will keep constant.Increasing illumination power of black lamps can significantly induce a higher concentration of SOA particle.The number of SOA particles will also be increased with increasing concentration of methyl nitrate.Lower NOx levels generate considerably more organic aerosol mass than do experiments with higher NOx levels.These compounds can be structurally categorized into three dasses：aromatic ring retaining products,nonarornatic ring reserved products and ring-opening products.

关 键 词：光化学 三甲苯 光氧化 二次有机气溶胶(SOA) 激光解吸附电离 

分 类 号：O644.1[理学—物理化学]