大气颗粒物高时间分辨采样和定量测量技术  

High Time-Resolved Sampling and Quantification Technique for Atmospheric Particulate Matter

作　　者：吴秀[1] 霍俊涛[1] 许涵乾[1] 陈宏[1] 杨新[1] 

机构地区：[1]复旦大学环境科学与工程系,上海200433

出　　处：《复旦学报（自然科学版）》2013年第1期55-61,共7页Journal of Fudan University：Natural Science

基　　金：上海市自然科学青年基金资助项目(10ZR1403300)

摘　　要：实现对大气颗粒物化学组分高时间分辨的定量测量是研究大气化学变化的关键.现报道了我们自行研制的高时间分辨的气溶胶微量采样器,可对不同粒径范围的大气颗粒物进行每1～6h的采样.并将电喷雾解析电离质谱(DESI-MS)技术应用于所采样品的化学成分分析.以大气气溶胶中的草酸分析为例,运用自制采样器进行了小时分辨的连续采样,在优化DESI-MS实验条件后,应用含1%氨水甲醇溶液作为喷雾溶剂,不需要对环境样品预处理或分离的前提下对气溶胶中的草酸进行了定量分析,得到了小时分辨的大气气溶胶PM2.5中草酸浓度的日变化.研究表明,高时间分辨气溶胶微量采样器与DESI-MS相结合可应用于大气气溶胶化学组分的快速定量分析,有助于研究特定化学组分的昼夜变化规律.Quantative analysis of chemical composition of atmospheric aerosol at high time resolution has been the focus for investigating chemical variation of atmosphere. It is reported our home-made highly time-resolved trace amount aerosol sampler, which can be applied to collect aerosols in different size ranges with time interval from 1 to 6 hours. Desorption ionization electrospray ionization mass spectrometry （DESI-MS） was employed to analysis the chemical compositions of these samples. Taking oxalic acid analysis for example, we collected size selected aerosol at hourly resolved sampling rate by our home-made sampler for several days. After the optimization for experimental conditions of DESI-MS, methanol with 1 ~ ammonia was used as the spray solution. The oxalic acid of these samples was quantatively analyzed without pretreatment or separation. Diurnal variations for oxalic acid in the PMas at hourly time resolution were obtained. It showed that our home-made sampler combined with DESI-MS can be used for rapid analysis of aerosol chemical composition and the diurnal changes for some specific compositions of aerosol.

关 键 词：大气颗粒物 高时间分辨采样 电喷雾解析电离质谱 草酸定量分析 

分 类 号：X131.1[环境科学与工程—环境科学]