| 成都市城区PM2.5中二次水溶性无机离子污染特征 |
| 摘要点击 5373 全文点击 2399 投稿时间：2014-05-06 修订日期：2014-06-30 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 PM2.5 二次水溶性无机离子 成都市 污染特征 来源 |
| 英文关键词 PM2.5 secondary water-soluble inorganic ions Chengdu City pollution characteristics source |
|
| 中文摘要 |
| 2009年4月~2010年1月在成都市城区采集131个PM2.5样品，应用离子色谱法对PM2.5中二次水溶性无机离子（NH4+、NO3-和SO42-）含量进行分析，并探讨其污染特征.结果表明，PM2.5中NH4+、NO3-和SO42-的平均浓度值分别为（10.4±8.6）、（19.7±14.6）和（32.8±21.8） μg·m-3，分别占PM2.5质量的（5.5±2.8）%、（11.1±3.5）%和（19.3±6.4）%，三者总和占PM2.5质量浓度的（35.9±12.7）%.PM2.5中NH4+、NO3-和SO42-的季节变化特征明显，夏、冬两季NH4+、NO3-和SO42-的浓度均为SO42->NO3->NH4+，其总和占PM2.5质量浓度的百分比为冬（44.3%）>夏（39.4%）.相关分析结果显示，NH4+、NO3-和SO42-在成都主要以NH4HSO4、（NH4）2SO4和NH4NO3形式存在；NO3-/SO42-比值表明，成都市大气中硫和氮的主要来源以固定源为主；硫氧化速率和氮氧化速率的年均值分别为：0.33±0.12和0.19±0.09，表明成都市PM2.5中SO42-和NO3-主要经二次转化形成. |
| 英文摘要 |
| A total of 131 samples of PM2.5 were collected at urban area of Chengdu from April, 2009 to January, 2010. The secondary water-soluble inorganic ions (NH4+, NO3- and SO42-) in PM2.5 were determined to study the pollution characteristics by Ion Chromatography method. The results showed the NH4+, NO3- and SO42- concentrations were (10.4±8.6), (19.7±14.6) and (32.8±21.8) μg·m-3, accounting for (5.5±2.8)%, (11.1±3.5)% and (19.3±6.4)% of PM2.5, respectively, and the sum of these three ions accounted for (35.9±12.7)%. Meanwhile, the seasonal characteristics of secondary inorganic ions were obvious. The seasonal concentrations order of secondary inorganic components was SO42- >NO3- >NH4+ in summer and winter, and the proportion of secondary inorganic ions of PM2.5 was 39.4% in summer and 44.3% in winter. The results of Correlation Analysis showed that most of NH4+, NO3- and SO2-4 existed as NH4HSO4, (NH4)2SO4 and NH4NO3 in Chengdu. And the average ratio of NO3-/SO42- indicated that the main source of sulfur and nitrogen in the atmosphere was given priority to a fixed source. In addition, the sulfate oxidizing rate (SOR) and nitrate oxidizing rate (NOR) were 0.33±0.12 and 0.19±0.09, respectively. It showed that SO42- and NO3- in PM2.5 were due to the secondary transformation. |
|
|
|
