【摘要】 本文采用安德森大气颗粒物分级采样器分别采集了宝鸡城郊灰霾天和非灰霾天的大气颗粒物,利用离子色谱仪进行水溶性无机离子组分的分析,探讨了宝鸡城郊大气颗粒物中离子组分的粒径分布特征;结合风向及气团后向轨迹,分析了大气污染物的区域传输对宝鸡大气颗粒物的影响.结果显示,灰霾天城区昼夜的颗粒物污染程度重于郊区,非灰霾天相反.宝鸡城郊灰霾天细粒子(PM_2.1)污染严重,城区高于郊区;总水溶性离子（TWSIs）对灰霾天颗粒物质量浓度的贡献率高于非灰霾天;城郊灰霾天昼夜二次离子（SNA）浓度均高于非灰霾天;灰霾天城区夜间是二次离子的重污染时段,二次离子中NO^-₃的浓度最高.城郊灰霾天昼夜Ca²⁺的浓度均低于非灰霾天.二次离子均呈双峰分布,主峰值均在细粒子中（0.43—1.1μm粒径段）,属于液滴模态.K⁺呈双峰分布,峰值分别在0.65—1.1μm和2.1—10.0μm粒径段,K⁺的粗细粒径分布在城郊昼夜存在着一定关联的转化.灰霾天和非灰霾天Ca²⁺的粒径分布均呈单峰分布,峰值在4.7—5.8μm粒径段.灰霾天宝鸡东部地区污染物自东向西的区域传输是宝鸡重污染发生的重要条件.更多还原

【Abstract】 To investigate chemical characteristics and source profiles of different size aerosol particles, eight-size particulate matter（PM） were collected in Baoji urban and suburban areas by Anderson atmospheric particle sampler and their water-soluble inorganic ions were analyzed using Ion chromatography. Additionally, the influence of air regional transport on atmospheric particulate matter in Baoji was analyzed by combining the wind direction and the air mass back trajectory method. The concentrations of daily PM were higher in the urban area than those in the suburbs and vice versa during haze periods. The pollution of fine particle matter(PM_2.1) was serious in urban and suburban areas in Baoji, with the higher concentrations in the urban area. Higher fraction of total water-soluble inorganic ions was observed in haze PM than that in non-haze PM. The concentrations of secondary ions（SNA） in haze days in both urban and suburban areas were higher than those in non-haze days. During haze days, the concentration of SNA, especially NO^-₃, were the highest at night than those in daytime. The concentrations of Ca²⁺ in haze days were lower than those in non-haze days. The SNA displayed a bimodal distribution and showed typical peaks in the droplet modes（0.43—1.1 μm）. The peaks of K⁺ concentration both occurred at smaller size distribution（0.65—1.1 μm） and larger size distribution（2.1—10.0 μm）, respectively, illustrating that K⁺ in coarse and fine particles may have a certain correlation with the conversion between day and night in urban and suburban areas. In contrast, the particle size distribution of Ca²⁺ exhibited a unimodal distribution with a high peak at the size of 4.7—5.8 μm. The transport of air pollutants from eastern to western part was an important reason for heavy pollution in Baoji.更多还原