半挥发性二次有机气溶六烯产品的化学老化
Christina N Vasilakopoulou1, Agata Blaziak2, Damianos Pavlidis1,3
1Institute of Chemical Engineering Sciences, FORTH/ICE-HT, Patras GR 26504, Greece.
概括
随着时间的推移,来自甲的后一代二级有机气溶 (SOA) 变得更加氧化. 这挑战了目前在大气中量化酸SOA的方法.
科学领域:
- 大气化学 大气化学
- 气溶科学 气溶科学
- 有机地化学 有机地化学
背景情况:
- 生物性挥发性有机化合物 (bVOCs) 的氧化是二次有机气溶 (SOA) 的主要来源.
- 甲是重要的bVOCs,有助于大气中的SOA.
- 了解SOA的演变对于气候和空气质量建模至关重要.
研究的目的:
- 从与OH基发生反应的化臭氧溶解产品中研究后一代SOA的形成.
- 确定老化酸SOA的氧化状态和光谱特征.
- 开发和测试一种高度氧化SOA形成的模型.
主要方法:
- 合成特定的第一代酸臭氧溶解产品.
- 使用OH基的受控反应实验.
- 使用气溶质谱 (AMS) 分析SOA,并计算氧与碳 (O:C) 的比率.
主要成果:
- 甲衍生SOA呈现渐进的氧化,平均O:C比为~0.6.
- 与新鲜的SOA相比,老化的SOA表现出明显的AMS质谱变化 (20-25°转移).
- 大约三分之二的碳在臭氧溶解中的SOA遵循了功能化路径.
结论:
- 后一代SOA来自基烯可以比以前假设的氧化程度要高得多.
- 由于正在进行的氧化,目前对甲SOA的量化方法可能不准确.
- 开发的物理化学模型和参数化可以改善未来的SOA建模工作.
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