来自中国北部的大气颗粒物中水溶性有机物质的尺寸解析分子特征
Cuiping Ning1, Yuan Gao2, Shuai Sun3
1School of Chemical Engineering, University of Science and Technology Liaoning, Anshan, 114051, China.
Environmental research
|June 19, 2024
概括
大气颗粒物中的水溶性有机物 (WSOM) 根据粒子的大小和位置而异. 中国北方的中国北方.
科学领域:
- 环境化学环境化学
- 大气科学 大气科学
- 分析化学 分析化学
背景情况:
- 大气中的颗粒物 (PM) 显著影响可见性,气候,生物地球化学循环和人类健康.
- 水溶性有机物 (WSOM) 是大气PM的关键,但复杂的组成部分.
- 了解WSOM的分子组成对于评估其环境和健康影响至关重要.
研究的目的:
- 描述WSOM在大小解析的大气PM中的分子组成.
- 为了比较中国北方的农村 (保定) 和城市 (大连) 地区之间的WSOM组成.
- 根据其分子签名来识别WSOM的潜在来源.
主要方法:
- 从宝和大连收集大小分辨率的颗粒样本 (0.01-18微米).
- 使用富里埃转换离子循环子共振质谱法 (FT-ICR MS) 对WSOM分子成分进行非向分析.
- 基于WSOM组成的来源分配分析.
主要成果:
- 艾特肯模式粒子 (<0.05微米) 中的WSOM在两个位置显示出相似的组成.
- 宝丁的积累模式粒子 (0.05-2μm) 主要由CHO化合物 (素,脂质) 组成,而大连的WSOM主要由含有S的化合物 (蛋白质,碳水化合物) 组成.
- 在这两个地点,CHO化合物是 WSOM 在粗模粒子 (>2μm) 中的主要贡献者.
结论:
- 大气PM中的WSOM成分受到粒子大小和地理位置 (农村与城市) 的强烈影响.
- 生物质燃烧和氧化反应是宝WSOM的关键来源.
- 煤炭燃烧,氧化反应和区域运输对大连的WSOM有很大的贡献.
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