Field and Laboratory Study of Rural Volatile Organic Compounds (VOCs) Oxidation and Secondary Organic Aerosol (SOA) Formation Utilizing Measurements of Formaldehyde and Glyoxal

气溶胶和臭氧（O3）影响人类健康、环境和气候。挥发性有机化合物（VOCs）的氧化，特别是通过羟基自由基（OH）的氧化，与O3的形成直接耦合，并有助于形成二次有机气溶胶（SOA），这是环境气溶胶的重要组成部分。作为南方氧化剂和气溶胶研究（SOAS）的一部分，主要研究人员（pi）计划进行全面的实验室和实地研究，重点是提高对OH和异戊二烯（最重要的挥发性有机化合物）控制过程的详细机制理解，特别是在农村环境中。目标是专门研究人为对生物源性VOC （BVOC）氧化和由此产生的SOA形成的影响。该项目解决了以下问题：1)目前的机制如何很好地代表VOC氧化，特别是对异戊二烯，特别是在低no条件下？2)鉴于最近发现的潜在测量干扰，目前的机制/模型如何很好地代表OH光化学？3)人为影响农村VOC氧化和O3和SOA形成的主要机制是什么？本研究旨在最终有助于改进前体排放对二次污染物影响的预测，并提高减轻排放对气候、人类健康和环境的人为影响的能力。这些项目还将开发一个大气化学有机标准图书馆（OSAC），这将是一个公开的在线数据库，旨在改善对实验室研究和校准标准起始材料的访问。

Aerosol and ozone (O3) affect human health, the environment, and climate. Oxidation of volatile organic compounds (VOCs), in particular via the hydroxyl radical (OH), is directly coupled to the formation of O3 and it contributes to secondary organic aerosol (SOA), an important component of ambient aerosol. As part of the Southern Oxidant and Aerosol Study (SOAS) the principal investigators (PIs) planned comprehensive laboratory and field studies focused on improving the detailed mechanistic understanding of the processes controlling OH and isoprene, the most important VOC, especially in rural environments. A goal is to specifically study the anthropogenic impact on biogenic VOC (BVOC) oxidation and resulting SOA formation. The project addresses the following questions: 1) How well do current mechanisms represent VOC oxidation, especially for isoprene, and in particular under low-NO conditions? 2) How well do current mechanisms/models represent OH photochemistry in view of recent findings of potential measurement interferences? 3) What are the dominant mechanisms of anthropogenic influence on rural VOC oxidation and resulting O3 and SOA formation? This research is designed to contribute ultimately to improved prediction of secondary pollutant effects from precursor emissions, and an improved ability to mitigate the anthropogenic effects of emissions on climate, human health, and the environment. The PIs also will develop a Library of Organic Standards for Atmospheric Chemistry (OSAC) that will be a publicly available online database aimed at enabling improved access to starting materials for laboratory studies and standards for calibrations.