Cao Run-Fang, Yan Yu-Long, Guo Li-Li, Guo Wen-di, He Qiu-Sheng, Wang Xin-Ming
School of Environment and Safety, Taiyuan University of Science and Technology, Taiyuan 030024, China.
State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510630, China.
Huan Jing Ke Xue. 2016 Jun 8;37(6):2034-2040. doi: 10.13227/j.hjkx.2016.06.005.
The distributions of size-segregated particles (PM) and water-soluble ions (WSIs) in Taiyuan were studied from July 2014 to April 2015 by TE-235 aerosol sampling and ion chromatography analyzing. As the results shown, the daily PM level was 173.7 μg·m, which exceeded the Grade Ⅱ limitation value in the Ambient Air Quality Standard (150 μg·m, GB 3095-2012). PM levels varied seasonally, and its were 199.1 and 194.2 μg·m in winter and spring, respectively, which were much higher than those in summer. The PM size-segregated was bimodal distribution for the range of 0-0.95 and 3.0-7.2 μm. The concentration of WSIs was the highest in winter, followed by summer and spring. SO, NO and NH were the main water soluble ions and accounted for 66% to 80% of the total WSIs. SO, K, NH and Cl showed a unimodal distribution at <0.95 μm in all samples, while Ca and Mg showed a bimodal distribution at <0.95 μm and 3.0-7.2 μm. NO showed a unimodal size distribution at <0.95 μm in winter and spring, compared with a bimodal distribution at <0.95 μm and 3.0-7.2 μm in summer. By the correlation analysis, PM and WSIs decreased with the increase of wind speed in summer and winter other than in spring for the road-dust re-suspension by strong wind. Based on the ratio analysis of NO/SO and Mg/Ca, coal combustion was the main source of NO and SO, while Mg and Ca were mainly from the dust and coal combustion.
2014年7月至2015年4月，通过TE - 235气溶胶采样和离子色谱分析，研究了太原不同粒径颗粒物（PM）和水溶性离子（WSIs）的分布情况。结果显示，日均PM浓度为173.7μg·m³，超过了《环境空气质量标准》（150μg·m³，GB 3095 - 2012）中的二级限值。PM浓度随季节变化，冬季和春季分别为199.1和194.2μg·m³，远高于夏季。PM粒径分布在0 - 0.95μm和3.0 - 7.2μm范围内呈双峰分布。WSIs浓度冬季最高，其次是夏季和春季。SO₄²⁻、NO₃⁻和NH₄⁺是主要的水溶性离子，占总WSIs的66%至80%。在所有样品中，SO₄²⁻、K⁺、NH₄⁺和Cl⁻在<0.95μm处呈单峰分布，而Ca²⁺和Mg²⁺在<0.95μm和3.0 - 7.2μm处呈双峰分布。冬季和春季，NO₃⁻在<0.95μm处呈单峰粒径分布，而夏季在<0.95μm和3.0 - 7.2μm处呈双峰分布。通过相关性分析，除春季因大风导致道路扬尘再悬浮外，夏季和冬季PM和WSIs随风速增加而降低。基于NO₃⁻/SO₄²⁻和Mg²⁺/Ca²⁺的比值分析，煤燃烧是NO₃⁻和SO₄²⁻的主要来源，而Mg²⁺和Ca²⁺主要来自扬尘和煤燃烧。
