春节期间南京市大气气溶胶粒径分布特征

Size Distributions of Aerosol During the Spring Festival in Nanjing

为研究春节期间燃放烟花爆竹对城市大气气溶胶数浓度粒径谱分布的影响，对2012年1月19～31日南京大气气溶胶数浓度、污染气体浓度和质量浓度进行了观测分析．结果表明，烟花爆竹的燃放期间10～20nm气溶胶浓度远低于非燃放期，50—100、100～200和200—500nm数浓度有较大增加，20～50nm和0．5—10μm气溶胶数浓度变化不大．烟花爆竹的燃放对气溶胶数浓度谱影响较大，非燃放期数浓度谱为双峰型分布；在燃放期数浓度谱为单峰性分布，且峰值向大粒径段偏移．烟花爆竹燃放期间质量浓度谱为双峰型分布，对细粒子的质量浓度影响较大，燃放期间PM2.5／PM10和PM1.0／PM10的值可升高10％．烟花爆竹的大量燃放对1．0～2．1μm粒径段气溶胶密度影响最大，对其他粒径段密度影响较小．

In order to investigate the firework burning impacts on spectrum distribution of atmospheric aerosol during the Spring Festival in Nanjing, number concentration and mass concentration of aerosol as well as mass concentration of gas pollutants were measured during January 19-31, 2012. The results indicated that the concentration of aerosol between 10-20 nm decreased, aerosol concentration in the range of 50-100 nm, 100-200 nm and 200-500 nm increased during the firework burning period comparing to those during the non-burnlng period. However, there was no obvious variation for aerosol between 20-50 nm and 0. 5-10 μm. The spectrum distribution of number concentration was bimodal during the non-burning period and unimodal during the burning period, with the peak value shifting to large diameter section. The mass concentration presented a bimodal distribution, the value of PM2.5/PMI0 and PM1.0/PMlo increased by 10% during the burning period. The firework burning events had big influence on the density of aerosol between 1.0-2. 1 μm.