南宁市一次污染过程大气颗粒物理化特性及来源

Physiochemical Properties and Sources of Atmospheric Particulate Matter During Pollution Monitoring in Nanning,China

利用颗粒物粒径谱仪和单颗粒气溶胶质谱仪等,对南宁市2016年12月5~11日大气污染过程进行实时监测,分析颗粒物粒径分布特征、化学组分及其污染来源.结果表明,观测期间南宁市20 nm^10μm颗粒物数浓度粒径主要集中在23~395 nm之间,主峰值出现在100 nm左右.期间有3次新粒子生成现象,下午14:00~18:00有30 nm左右新粒子开始生成,晚20:00~次日06:00碰并长大到40~110 nm左右,3次新粒子生成过程受机动车尾气一次排放的污染影响.对污染期间细颗粒物化学成分在线溯源分析发现,污染期间有大量的二次反应颗粒物生成,判定颗粒物来源主要有生物质燃烧源、扬尘源和燃煤源,其中,远距离传输对生物质燃烧源有贡献.

Distribution characteristics,chemical constituents,and sources of particulate matter were measured using a scanning mobility particle sizer and single particle aerosol mass spectrometer during pollution monitoring that occurred between December 5^th and December 11 th,2016,in Nanning.Results showed that particulate matter（PM） sized between 20 nm -10 μm were concentrated in the 23 to 395 nm range,with a peak of 100 nm.Three new particle types were generated during the course of this monitoring.These new 30 nm particles came into existence between 14： 00 to 18： 00,and grew to a size of between 40 nm and 110 nm between 20： 00 to 06： 00 the next day.The generation of the all three new particles was affected by motor vehicle exhaust emissions.Many secondary particles were also produced during this period of pollution.The source of the fine particulate matter was mainly from the burning of biomass,dust,and the combustion of coal.In addition,a long-distance transmission also contributed to the particles from biomass burning.