北京市大气气溶胶PM2.5中极性有机化合物的测定

Abstract

提出了用GC-MS分析大气细粒子中极性有机化合物的测定方法,给出了2类衍生化反应的最佳条件.标准物质工作曲线相关系数在0.995～1.000之间,仪器精密度为1%～10%,标准物质的标准偏差为3%～20%,实际样品的标准偏差为3%～17%,仪器定量限为0.1～4.0 ng*μL-1.实测了北京市夏、秋、冬3季大气细粒子样品,定量极性有机化合物42种,其中一元羧酸30种、二元羧酸5种、无水单糖3种、甾醇类3种和苯甲酸,并对这些化合物的可能来源进行了探讨.

A determination method was developed for the quantification of polar organic compounds in atmospheric fine particles in Beijing City by GC-MS. The optimally reactive conditions of two derivative methods were set up. The related coefficients (R2) of standard curves were 0.995-1.000. The precise of the GC-MS was 1%-10%, and the quantified detection limits ranged from 0.1 to 4.0 ng x microL(-1) depending on the various standard compounds. The percent relative standard deviation of standards and atmospheric samples were 3%-20% and 3%-17%, respectively. The methods were applied for Beijing fine particle samples in summer, fall, and winter in 2002. Total 42 polar organic compounds were identified and quantified, including 30 n-aliphatic and n-alkenoic acid species, 5 aliphatic dicarboxylic acid species, 3 monosaccharide anhydrides, 3 steroids, and benzoic acid. The sources of these compounds were discussed.