上海市交通干道颗粒物中水溶性无机离子的污染特征

2011年2月至2011年6月在上海市中心城区交通干道区采集29个TSP样品,对颗粒物中水溶性无机离子的化学特征进行了分析比较。结果表明:在9种水溶性无机离子(F-、Cl-、NO3-、SO42-、NH4+、Ca2+、K+、Mg2+和Na+)中,SO42-和NO3-浓度最高,分别占水溶性无机离子总浓度的36.1%和30.6%。颗粒物的阴离子/阳离子比值平均为1.12,相关性方程的斜率K为1.02,说明颗粒物偏酸性。计算的NO3-/SO42-比值的均值为0.85,表明移动排放源(机动车)对颗粒物中水溶性组分的贡献已接近于固定排放源(燃煤)。计算得出硫的转化率(SOR)均值为0.28(0.12～0.51),氮的转化率(NOR)均值为0.19(0.06～0.40),表明二次颗粒物生成是主要来源之一。

Characteristics of Water Soluble Inorganic Ions in Atmospheric Particles in Shanghai Traffic Zone

Twenty nine atmospheric particle（TSP） samples were collected in traffic zone in Shanghai downtown from Feb.2011 to June 2011.The water soluble inorganic ions in particles were analyzed and compared.Results indicated that sulfate and nitrate occupied 36.1% and 30.6% of nine water soluble inorganic ions（F-,Cl-,NO3-,SO42-,NH4＋,Ca2＋,K＋,Mg2＋ and Na＋）,respectively.The average ratio of anion equivalent over cation equivalent reach 1.12 and the slope was 1.02 demonstrating particle is acidic.The average NO3-/SO42-ratio was 0.85 which showed the contribution of mobile emission sources（traffic emission） is close to that of stationary emission source（coal burning）.The conversion rate of sulfur（SOR） and nitrogen（NOR） were 0.28（0.12~0.51） and 0.19（0.06~0.40） respectively,which implies that secondary particle formation is one of main sources.