Analyses of Insoluble Components in Rain and Snow of Beijing by Electron Microscope
电子显微镜分析北京雨雪中不可溶成分

During the seasons of winter and summer in 1994-1995 eleven processes of rain and snow belong to different types were observed in Peking University. Precipitation samples were continuously collected and filtered for each rain or snow process. Weight-percentage distributions of 15 elements ( Si,Fe,Al,K,Ca,Cu,Ti, Mg,Na,P,S,Cl,Ni,Mn, and Cr ) in insoluble components were measured by electron microscope for 28 filtered samples of all precipitation processes. Using averaging method, cluster analysis and correlation analysis of elements, material composition and sources for insoluble components in precipitation were discussed.