作　　者： ; ; ; ; ; ; ; ;

机构地区： 上海大学环境与化学工程学院射线应用研究所

出　　处： 《环境科学》 2007年第3期472-477,共6页

摘　　要： 采集了上海市区和郊区春季和夏季的大气PM2.5样品,分析了市区和郊区春夏2季PM2.5质量浓度变化的规律,使用PIXE(Proton Induced X-ray Emission)分析技术获得S、K、Ca、Ti、Cr、Mn、Fe、Ni、Cu、Zn、As、Se、Br、Sr、Pb等15种元素的质量浓度.结果表明,上海PM2.5中化学元素的质量浓度在春季(5038.6ng.m-3)比在夏季(3810.6ng.m-3)高,春季郊区(2528.9ng.m-3)和市区(2509.7ng.m-3)PM2.5中化学元素的质量浓度相当,夏季市区样品(1674.2ng.m-3)中化学元素质量浓度的总量比郊区(2136.3ng.m-3)的低,但来自人为污染的化学元素(Cr、Mn、Ti、Ni、Cu、Zn、As、Br、Sr、Pb)在市区PM2.5中的含量较高;场发射扫描电镜(FESEM)分析显示,上海PM2.5主要由烟尘集合体、燃煤飞灰、矿物颗粒、生物质颗粒和不明物质组成,质粒DNA评价揭示上海市区PM2.5比郊区的具有更强的生物活性,主要原因可能在于市区样品中含有较高的重金属元素和较多的烟尘集合体. PM2.5 was collected at Shanghai urban and suburban sites during spring and autumn. PIXE （Proton Induced X-ray Emission） was used to investigate mass concentration of 15 elements （ S, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Sr, Pb ） in Shanghai PM2.5. The total mass concentration of the 15 chemical elements was higher in spring （5 038.6 ng·m^-3 ） than in summer （3 810.6 ng·m^-3 ）. In spring, mass concentrations of these elements in urban and suburban samples were in the same level. In summer, concentration of the elements in urban samples were lower than in suburban samples, however, the elements which were originated from anthropogenic resources were in higher level in urban samples. The results of FESEM showed that Shanghai PM2.5 was consisted of soot aggregates, coal fly ashes, minerals, bio-particles and unidentified particles. The result of Plasmid DNA assay demonstrated bioreactivity of urban PM2.5 was more reactive than that of suburban PM2.5, this phenomenon probably was explained by higher mass level of heavy metals and more proportion of soot aggregates in urban PM2.5.

关 键 词： 化学元素 场发射扫描电镜 生物活性

领　　域： [环境科学与工程]