中文摘要：

超大城市大气环境日益改善的同时,其周边卫星城市的大气环境将逐步得到关注。利用静电低压撞击器（ELPI）在线测量上海周边卫星城市太仓大气细颗粒物（PM2.5）粒子数浓度和质量浓度的粒径分布;结合太仓大气PM2.5样品中Ca、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Se、Sr、Cd和Pb等15种元素的浓度,计算元素的富集因子,分析了太仓大气PM2.5的主要来源。太仓大气PM2.5样品的粒子数浓度呈单峰结构,质量浓度呈双峰结构;粒子数浓度和质量浓度均为晚间高于白天。太仓大气PM2.5样品中除Se外的其余14种元素浓度均低于同时期上海市嘉定区、南京、杭州等周边城区的相应值,但Ca、Ti、V、Mn、Ni、Cu、Zn、As、Se、Sr和Pb的富集因子却大于同时期这些周边城区的相应值。源分析表明,太仓大气PM2.5受城市建设和工业加工企业等的影响较为严重。

英文摘要：

With the continue improvement of atmospheric environment in Mega-City,the atmospheric conditions of the surrounding satellite city has received wide public concern.In the present study,both the number and mass weighted size distributions of fine particles（0.03-2.50 μm） in Taicang,a satellite city surrounding Shanghai,were online determined by ELPI.The source analysis was conducted by using mass concentrations and enriched factors of 15 trace elements（Ca,Ti,V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Se,Sr,Cd,Pb） in the PM2.5.Results show that the concentrations of airborne fine particles in Taicang were higher in night than in daytime.The number weighted size distributions clearly showed a unimodal mode,while the mass weighted size distributions was bimodal distributed.The concentrations of monitored elements,except for Se,in PM2.5 in Taicang were lower than that in other nearby cities,but the enriched factors of Ca,Ti,V,Mn,Ni,Cu,Zn,As,Se,Sr and Pb were relative high.The source analysis showed that those main enriched elements（such as Ca,Ni,Zn,As,Se,Cd,Pb） of PM2.5 in Taicang were affected by urban construction and small-scale processing enterprises.