| 春季沙尘过程北京市不同粒径大气气溶胶污染特征及来源分析 |
| 摘要点击 2536 全文点击 959 投稿时间：2018-04-28 修订日期：2018-06-05 |
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| 中文关键词 沙尘天气 水溶性有机碳(WSOC) 水溶性无机离子 后向轨迹(HYSPLIT) 气象条件 |
| 英文关键词 dust weather water-soluble organic carbon (WSOC) water-soluble ions backward trajectory model (HYSPLIT) meteorological condition |
| 作者 | 单位 | E-mail | | 杨阳 | 首都师范大学化学系分析测试中心, 北京 100048 | yy15010061956@sina.com | | 李杏茹 | 首都师范大学化学系分析测试中心, 北京 100048
华东师范大学地理科学学院, 地理信息科学教育部重点实验室, 上海 200241 | | | 陈曦 | 首都师范大学化学系分析测试中心, 北京 100048 | | | 刘水桥 | 首都师范大学资源环境与旅游学院, 北京 100048 | | | 刘雨思 | 首都师范大学化学系分析测试中心, 北京 100048 | | | 徐静 | 首都师范大学资源环境与旅游学院, 北京 100048 | | | 王莉莉 | 中国科学院大气物理研究所, 大气边界层物理和大气化学国家重点实验室, 北京 100029 | | | 陶明辉 | 中国地质大学(武汉)地球科学学院, 武汉 430074 | | | 王格慧 | 华东师范大学地理科学学院, 地理信息科学教育部重点实验室, 上海 200241 | wanggh@ieecas.cn |
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| 中文摘要 |
| 为了解沙尘气溶胶在大气中的物理、化学特性演变，于2017年5月北京沙尘暴发期间，对北京大气中不同粒径颗粒物的质量浓度进行了连续观测，并用离子色谱仪和水溶性有机碳分析仪对其中的主要水溶性化学组分进行了检测.结果表明，沙尘期间TSP及其中的水溶性有机碳（WSOC）、元素碳（EC）、有机碳（OC）和水溶性无机离子的平均质量浓度分别为（2237.59±681.49）、（29.90±18.05）、（1.46±3.05）、（67.35±29.07）和（136.75±46.38）μg·m-3，除EC变化不大外，其他成分沙尘期浓度远高于非沙尘期，其中Na+、NH4+、K+、Mg2+、Ca2+、Cl-、NO3-、SO42-、WSOC的浓度分别为沙尘前的11.55、3.00、14.88、14.89、9.40、4.60、2.40、3.91、1.83倍，浓度增长最为明显的是地壳元素离子，变化最小的为NH4+和NO3-；粒径分析表明，地壳元素离子在整个采样期间均在粗粒径段（4.7~5.8 μm）表现出最大浓度；沙尘期间SO42-及NO3-均以粗模态为主，沙尘结束后SO42-在0.43~0.65 μm粒径段出现峰值，而NO3-依然是在4.7~5.8 μm粒径段出现峰值，表明大部分NO3-主要以非均相反应存在于粗粒径段中.沙尘期SO42-与地壳元素离子表现显著的正相关关系，与NH4+没有表现出相关性，表明沙尘期SO42-主要来自于沙尘携带的一次来源，非沙尘期SO42-与地壳元素没有明显的相关性，而与NH4+之间相关系数r=0.70，表明其为非均相二次转化形成.NO3-与地壳元素离子和NH4+的相关性分析表明其在沙尘期既有一次来源，也有二次转化，而在非沙尘期主要来源于二次转化过程. |
| 英文摘要 |
| To understand the evolution of the physical and chemical properties of dust aerosols in the atmosphere, the concentrations and chemical compositions of differently sized particles were continuously observed and analyzed using an ion chromatograph and carbonaceous analyzer during the outbreak of dust in May 2017 in Beijing. The concentrations of total suspended particulate (TSP), water-soluble organic carbon (WSOC), elemental carbon (EC), OC, and water-soluble inorganic ions were (2237.59±681.49), (29.90±18.05), (1.46±3.05), (67.35±29.07), and (136.75±46.38) μg·m-3 during the dust period, respectively, and significantly exceeded that of the non-dust period, except for EC. The Na+, NH4+, K+, Mg2+, Ca2+, Cl-, NO3-, SO42-, and WSOC concentrations during the dust storm period were 11.55, 3.00, 14.88, 14.89, 9.40, 4.60, 2.40, 3.91, and 1.83 times higher than that during the non-dust period. The growth of crustal ions, such as Ca2+ and K+, was notably the largest and NH4+ and NO3- were minimal. The size distribution indicates that crustal ions primarily occur in the coarse mode during the whole sampling campaign. The SO42- and NO3- ions are slightly bimodal during the dust storm, with a dominant peak in the coarse mode at 4.7-5.8 μm and a very minor peak in the fine mode with a size range of 0.43-0.65 μm. During the non-dust period, SO42- is the dominant mode in the fine mode, while NO3- changes little compared with that during the dust period, which indicates that heterogeneous reaction with crustal ions is the main formation mechanism of NO3- in the coarse mode. A significant positive correlation was observed between SO42- and the sum of crustal ions during the dust period, indicating that the source of SO42- during the dust period is remote transmission of the dust storm. During the non-dust period, the positive correlation of SO42- with NH4+ indicates that secondary formation is the main source of SO42-. Based on correlation analysis of NO3- with crustal ions and NH4+, both remote transmission and secondary formation are the sources of NO3- during the dust storm and heterogeneous reactions are predominant during the non-dust period. |
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