【作者】 胡敏； 赵云良； 何凌燕； 黄晓锋； 唐孝炎；

【Author】 Hu Min, Zhao Yunliang, He Lingyan, Huang Xiaofeng, Tang Xiaoyan State Key Joint Laboratory of Environment Simulation and Pollution Control, College of Environmental Sciences, Peking University, Beijing, 100871

【机构】 环境模拟与污染控制国家联合重点实验室北京大学环境学院；

【摘要】 为认识北京大气颗粒物污染重要特性之一的颗粒物谱分布特征,本文采用MOUDI对北京城区大气进行四次分别持续一周的采样,采样时间是2001年7月、2002年3月、2002年7月和2003年1月;通过分析获得了颗粒物及其离子成分的质量浓度谱分布;发现北京城区颗粒物中细粒子和粗粒子与PM10的质量浓度都有很强相关性(R2>80%),细粒子占整个PM10的40-60%;硝酸盐、硫酸盐和铵盐在细粒子中所占比例之和在重污染日大于70%,是重污染日颗粒物浓度升高的主要因素;并且观测到颗粒物的质量谱分布在积聚模态存在两个亚模态以及积聚模态出现在1-1.8μm的粒径段的谱分布的现象。更多还原

【Abstract】 In order to understand one of the important characteristics of Beijing particulate matter pollution - mass size distribution of particulate matter as well as its water soluble ions. The particle samples were collected by using a MOUDI cascade impactor in Beijing, four times of one week each during July 2001, March 2002, July 2002 and January 2003. The results indicate that there is a relatively strong correlation between PM1.8 and PM10(R2>80%) , the same to PM (1.8-10) (PM10 minus PM1.8); the ratio of PM1.8/PM10 varieties between 40% and 60%. Sulfate, nitrate and ammonium are the main components and the percent of these three ions in PM1.8 is over 70% in the heavy pollution day; they are the main reason increasing particle concentration. The phenomenon was found that there are "two modes" in the diameter range of the fine particle, "condensation mode" and "droplet mode". The peak of the accumulation mode was also found to appear in the diameter range of 1-1.8μm.更多还原