【摘要】 运用色度分析的方法分析不同月份降尘的组成.计算结果与通过元素分析方法的较一致,说明这种方法用于分析降尘的成分是可行的.与元素分析方法相比较,这一方法的优点在于能够计算不同月份降尘的组成,而元素分析法只能计算整体值.计算结果显示:兰州市冬季(11-2月)大气降尘以污染物为主要成分,所占比例为77.78％.这一期间污染物的沉降量占全年的57.5％.兰州市沙尘暴影响最为严重的时期为春季的3,4月份,其这一期间的沙尘降尘量占到了全年沙尘沉降量的48.9％,在当月降尘中沙尘所占比例分别为67.7％和71.7％.更多还原

【Abstract】 The method of color index was first used in this dissertation in analyzing deposited dust. The result was consistent with the result of Yang Li-ping by factor analysis. Compared with factor analysis, the method of color index can distinguish ingredient of deposited dust in different months. Pollution-derived particle were predominant ingredient in deposited dust of Lanzhou in winter, it accounted for 77.8% of the total deposited dust in this period and accounted for 57.5% of the whole year pollution-derived particle. Sand-dust storms influence Lanzhou serious in March and April, in this period sand dust accounted for 67.7% of the total deposited dust, and accounted for 48.9% of the whole year.更多还原