Volatile Product Formation and Atmospheric Lifetimes of Biogenic Organic Aerosols

该项目的重点是更好地了解活性碳在大气中的演变。将进行高度受控的环境室内实验，以评估有机气溶胶的老化化学。实验将有助于确定气溶胶老化的程度取决于颗粒特性(如液态水、无机成分、pH、有机成分和表面积)以及环境条件(如温度和相对湿度)。研究的目的是：(1)量化羟基自由基(OH)引发的悬浮有机气溶胶(OA)氧化生成含氧挥发性有机化合物(OVOC)和氧化寿命；(2)表征物理、化学和环境参数如何影响被调查的生物源OA的OH寿命和OVOC产生；(3)研究了水相和非均相OH氧化的机理差异；(4)研究了直接光解对光催化活性的影响。这项研究将为模拟大气中活性碳的大气模型提供重要的新数据输入和约束。预计这些结果将显著提高人们对半挥发性物质和颗粒物如何影响气候、空气质量和健康的理解。

This project is focused on developing a better understanding of how reactive carbon evolves in the atmosphere. Highly controlled environmental chamber experiments will be conducted to evaluate the aging chemistry of organic aerosol. Experiments will help to determine the extent to which aerosol aging depends on particle characteristics (such as liquid water, inorganic composition, pH, organic composition, and surface area) as well as environmental conditions (such as temperature and relative humidity).The objectives of the research are to: (1) Quantify the production of oxygenated volatile organic compounds (OVOC) and the oxidative lifetimes from hydroxyl radical (OH)-initiated oxidation of suspended organic aerosol (OA); (2) Characterize how physical, chemical, and environmental parameters affect the OH lifetime and OVOC production of the biogenic OA under investigation; (3) Investigate the difference in mechanism between aqueous OH and heterogeneous OH oxidation; and (4) Study the effects of direct photolysis on OA. This research will provide important new data inputs and constraints for atmospheric models that simulate reactive carbon in the atmosphere. The results are expected to significantly improve the understanding of how semi-volatiles and particles affect climate, air quality, and health.