亚青会期间南京市气溶胶中OC和EC的粒径分布

Size Distribution and Characterization of OC and EC in Atmospheric Aerosols During the Asian Youth Games of Nanjing,China

采用Anderson 9级撞击式采样器和DRI Model 2001A热/光碳分析仪对南京2013年8月10~28日亚青会期间不同粒径段气溶胶中有机碳(OC)和元素碳(EC)的质量浓度进行了观测分析.结果表明,51.55%和54.81%的OC和EC富集于粒径<1.1μm的细粒子中,亚青会期间OC和EC的最大浓度分别位于0~0.43μm和0.43~0.65μm粒径段,占总浓度的比例分别为20.90%±5.02%和22.68%±9.90%.PM1.1、PM1.1~2.1和PM2.1~10中OC和EC的浓度在亚青会期间比亚青会前分别减少了43.44%~56.17%和59.17%~73.55%.亚青会期间OC的谱分布没有变化,均为双峰型分布;EC的谱分布由双峰型变为单峰型.观测期间不同粒径段的EC和OC具有较好的同源性.亚青会前OC和EC主要来自汽车尾气;亚青会期间PM1.1中OC和EC主要来自汽车尾气,PM1.1~2.1和PM2.1~10中OC和EC主要来自汽车尾气和燃煤.

Aerosol samples were collected by an Andersen cascade impactor ( Andersen) in Nanjing during the Asian Youth Games (AYG), and organic carbon (OC) and elemental carbon (EC) in particles were determined by DRI Model 2001A carbon analyzer of USA. Observations indicated that OC (51. 55℅) and EC (54. 81℅) were enriched in the fine aerosol particles with size below 1. 1μm, the highest mass concentrations of OC and EC were located at 0-0. 43 μm and 0. 43-0. 65 μm, respectively, accounting for 20. 90℅ ± 5. 02℅ and 22. 68℅ ± 9. 90℅ of the total concentration. The mass concentrations of OC and EC in PM1. 1 , PM1. 1-2. 1 and PM2. 1-10 during AYG period were decreased by 43. 44℅-56. 17℅ and 59. 17℅-73. 55℅ as compared to the values before AYG. The spectral distribution of OC was bimodal during the whole observation period, while the spectrum distribution of EC was changed from bimodal to unimodal. OC and EC during the observation period were in good homology. OC and EC were attributed to automobile exhaust fumes before AYG. During AYG, OC and EC in PM1. 1 were mostly from automobile exhaust fumes, while OC and EC in PM1. 1-2. 1 and PM2. 1-10 were from automobile exhaust fumes and coal combustion.