云下污染气体清除作用的物理化学因子

PHYSICO-CHEMICAL SCAVENGING FACTORS IN THE GASEOUS POLLUTANTS BELOW CLOUDS

本文在物理化学模式的基础上讨论了雨滴对云下污染气体SO_2、H_2O_2、O_3、NH_3、CO_2的冲刷过程。除了H_2O_2、O_3与S(Ⅳ)的液相化学反应以外,还考虑了Fe^(3+)、Mn^(2+)的催化氧化作用。计算结果表明:(1)存在雨滴SO_4^(2-)浓度谱和PH值谱的可能性;(2)云下气体冲刷决定于下列因子:雨滴内污染物的初始浓度、降水强度和NH_3气体浓度等;(3)模式结果可用于解释一些观测现象。

The process of scavenging below-cloud pollutants (SO_2, H_2O_2, O_3, NH_3, CO_2)by raindrops is studied,based on a physico-chemical model. Besides the aqueous oxida-tiom of S(Ⅳ) by H_2O_2 and O_3,the catalyic oxidations of S(Ⅳ) by Fe^(3+) and Mn^(2+) in thefalling drops are also considered. Results indicate: (1)the[SO_4^(2-)] and pH spectra can bede developed; (2)the scavenging process below clouds is influenced by a number of fac-tors: initial concentration of pollutants in the raindrops,precipitation intensity and NH_3concentration, and (3) this study can be uded for explaining some phenomena observedfrom field measurements.