Collaborative Research: Investigating Secondary Organic Aerosol (SOA) Formation in Central Los Angeles for Research at the Nexus of Air Quality and Climate Change (CalNex 2010)

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。该项目的目的是确定在受污染的城市大气中产生二次有机气溶胶（SOA）的主要来源和物理化学过程。主要研究人员将通过参与2010年空气质量和气候变化研究（CalNex）实验来调查洛杉矶SOA。该项目将在2010年6月和7月为期6周的时间内，支持在洛杉矶中部部署和应用先进的仪器和数据分析技术，用于有机微量气体和细颗粒有机气溶胶的化学表征。通过自动热解吸气溶胶气相色谱仪对有机气溶胶进行非常详细的原位化学形态分析，并对集成过滤器收集的元素碳、有机碳、水不溶碳和水溶性碳进行放射性碳分析，将为确定SOA前体的来源提供独特的数据。影响气/粒子分配的过程和因素将用能够测量气相和粒子相成分的仪器进行探索。颗粒进液采样器、雾室和总有机碳（TOC）分析仪（PILS/MC/TOC）的组合将全面测量水溶性气体/颗粒的分配。这将通过配备热解吸入口的高分辨率质子转移飞行反应时间质谱仪对气体/颗粒有机酸（PILS/MC/离子色谱）以及挥发性和半挥发性有机化合物进行化学特定测量来增强。这些仪器将增加CalNex洛杉矶中心地面站点的测量能力，并通过实验后的深入数据分析为解决科学目标提供独特的数据集。该项目将建立在河滨有机气溶胶研究（SOAR-2005）中开始的强有力的合作基础上，继续调查城市环境中SOA的来源和转变。分析方法和测量能力的发展，长时间内各种仪器的操作，以及大数据集的分析将需要一系列的技术能力，使该项目非常适合本科生和研究生的研究团队以及博士后研究，并促进来自不同背景和学科领域的研究人员的互动。这些同事所获得的知识和经验对大气化学和当地空气质量社区都很有价值。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The objective of this project is to identify major sources and physico-chemical processes that produce secondary organic aerosol (SOA) in a polluted urban atmosphere. The principal investigators will investigate Los Angeles SOA through participation in the Research at the Nexus of Air Quality and Climate Change (CalNex) 2010 experiment. This project will support the deployment and application of advanced instrumentation and data analysis techniques for chemical characterization of organic trace gases and fine particle organic aerosol in central Los Angeles during a 6-week period in June and July 2010. Highly detailed in-situ chemical speciation of organic aerosol by automated Thermal-desorption Aerosol Gas Chromatograph, and radiocarbon analysis of elemental, organic, water-insoluble, and water-soluble carbon collected on integrated filters will provide unique data to identify sources of SOA precursors. Processes and factors affecting gas/particle partitioning will be explored with instruments capable of measuring both gas- and particle-phase components. A combination of Particle Into Liquid Sampler, Mist Chamber and Total Organic Carbon (TOC) analyzer (PILS/MC/TOC) will comprehensively measure water-soluble gas/particle partitioning. This will be augmented by chemically specific measurements of gas/particle organic acids (PILS/MC/Ion Chromatography), and volatile and semi-volatile organic compounds via high-resolution Proton-Transfer Reaction Time of Flight Mass Spectrometer equipped with a thermal-desorption inlet. These instruments will add to the measurement capabilities at the CalNex central Los Angeles ground site and provide a unique data set for addressing the scientific objective through in-depth data analysis following the experiment. This project will build upon the strong collaboration started in the Study of Organic Aerosols in Riverside (SOAR-2005) to continue investigation of SOA sources and transformation in the urban environment.Development of analytical methods and measurement capabilities, the operation of a wide range of instruments over extended periods, and analysis of the large data sets will require a range in technical ability and make the project well suited for research teams of undergraduate and graduate students, and post-doctoral researches, and promote interaction with researchers from diverse backgrounds and disciplinary areas. Knowledge and experience gained by these co-workers will be valuable to both the atmospheric chemistry and local air quality communities.