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前言随着大工业的高度发展和城市人口的迅猛增加,大气中有毒重金属元素对环境的污染日趋严重,给人类的健康造成危害,已引起人们极大关注.分析降雪中 Cd、Cr 和 Pb,是监测北方城市冬天大气污染程度的一种独特的方法。镉,铬和铅,是环境要素中有毒重金属元素,是有潜在危害的污染物。北方冬季长达4—5个月,气温低至零下35℃,由于取暖、有色金属冶炼、汽车尾气,排出大量烟气和尘埃。冬季又易形成逆温层,污染物不易扩散,故北方城市冬季污染更为严重,在城市大气中镉的含量年平均0.15ng/m~3,铬:0.07—2.5ng/m~3,铅:80—167ng/m~3,这
Preface With the great development of large industries and the rapid increase of urban population, the pollution of toxic heavy metal elements in the atmosphere has become increasingly serious to the environment, which has caused great harm to human health.Analyzing the contents of Cd, Cr and Pb, It is a unique way of monitoring winter air pollution in northern cities. Cadmium, chromium and lead, toxic heavy metals in environmental elements, are potentially harmful pollutants. The northern winter up to 4-5 months, the temperature as low as minus 35 ℃, due to heating, non-ferrous metal smelting, car exhaust, discharge large amounts of flue gas and dust. In winter, it is easy to form an inversion layer, and the pollutants are not easily diffused. Therefore, the pollution in northern cities is more serious in winter. The content of cadmium in urban air is 0.15ng / m ~ 3 on an average, 0.07-2.5ng / m ~ 3 for chromium, : 80-167ng / m ~ 3, this