Through simulated acid rain test, it draw the conclusion that PM2; -bound heavy metals Cu, Pb, Zn, Cd, Ni and Cr have varying degrees of dissolution in the simulated acid rain. The dissolved percentages of heavy metals increased with the decreases of pH values, suggesting that the increasing acidity can accelerate the release of heavy metals in PM25. Its also indicated that acid rain will increase the mobility and pollution of PM25 -bound heavy metals in the environment. The dissolved percentages of heavy metals in spring of 2007 are higher than that in autumn of 2006 at the same pH value of simulated acid rain, which maybe due to the higher percentage of unstable fraction metals in the spring of 2007. It indicates that unstable fraction metals absorbed in participate matter are easier to release in the acidic condition, and acid rain will increase the mobility and pollution capacity of heavy metals in atmospheric particulates in the environment.%通过模拟酸雨溶出试验发现,在模拟酸雨浸提作用下大气细颗粒物PM25中重金属元素Cu、Pb、Zn、Cd、Ni、Cr都有不同程度的释放,且溶出率随模拟酸雨pH降低而增加,说明酸性加强能加速PM25中重金属元素的释放.在同一pH模拟酸雨作用下,2007年春样品中各重金属的溶出率均比2006年秋高,2007年春重金属不稳定态比例普遍比2006年秋高,说明在酸性条件下吸附在颗粒物中的不稳定态重金属更容易释放出来,酸雨会增加大气颗粒物中重金属在环境中的迁移性和污染能力.
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