通过气相和水相反应形成的二级有机气溶之间的化学差异
Wenqing Jiang1,2, Lu Yu1,2, Lindsay Yee3
1Department of Environmental Toxicology, University of California, Davis, California 95616, United States.
概括
生物质燃烧释放的化合物通过气相和水相反应形成二级有机气溶 (SOA). 与气相反应相比,水态反应产生了更多的SOA,形成了与气相反应相比不同的化学成分,如寡合物和碳酸.
科学领域:
- 大气化学 大气化学
- 生物质燃烧排放的排放量
- 二次有机气溶形成
背景情况:
- 化合物是生物质燃烧 (BB) 的关键排放物.
- 这些化合物在气相和水相中反应,形成二级有机气溶 (SOA).
- 气相SOA (gasSOA) 和水相SOA (aqSOA) 的形成涉及不同的机制,产生不同的产品.
研究的目的:
- 为了研究瓜亚科尔的气态和水态反应,一个代表性的BB.
- 为了阐明烯酸aqSOA和气体SOA之间的组成差异.
- 为了比较SOA产量和两个阶段的进化路径.
主要方法:
- 研究了瓜亚科尔的气态和水态反应.
- 分析的SOA产量和化学成分 (氧化状态,分子量,功能组).
- 确定了天然气SOA和aqSOA的特征光谱特征和痕迹离子.
主要成果:
- 瓜亚科尔的水相反应产生了更高的SOA产量 (约. 60%) 比气相反应 (大约. 只有30%).
- 最初,天然气SOA的氧化水平 (O/C>0.82) 比aqSOA高 (0.55-0.75),但长时间的水态反应增加了aqSOA的氧化.
- 水性反应产生了更多的寡合物,高分子量化合物和持续的碳酸生产.
结论:
- 气SOA和aqSOA表现出显著的化学差异.
- 水态反应更复杂,导致SOA更渐进的进化.
- 对气体和水路的准确表示对于预测气溶特性和生物质燃烧影响的大气模型至关重要.
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