Chemical Mechanisms of Nucleation and Growth of Secondary Organic Aerosol from the Oxidation of Biogenic Compounds

生物化合物氧化产生的二次有机气溶胶成核和生长的化学机制

• 批准号: 0328718
• 负责人: Paul Ziemann
• 金额: $ 29.74万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-10-01 至 2007-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0328718&HistoricalAwards=false
• 关键词: Chemical; Mechanisms; Nucleation; Growth; Secondary

The overall objective of this project is to use a suite of analytical techniques to elucidate the detailed chemical and physical mechanisms involved in the nucleation and subsequent growth of secondary organic aerosol (SOA) from the oxidation of selected volatile organic compounds (VOCs) via gas phase and heterogeneous reactions. Work on this project will begin with the development of a new technique for analyzing the chemical composition of organic aerosol particles. This will involve coupling an ion trap mass spectrometer (ITMS) to a thermal desorption particle beam mass spectrometer (TDPBMS) that has been developed for real-time particle chemical analysis. These TDPBMS techniques will then be used with others to investigate the chemistry of SOA formation from reactions of selected monoterpenes and model compounds with ozone, hydroxyl radicals, and nitrate radicals in a large-volume environmental chamber. The chemistry of particle nucleation in these reactions will be studied by using a laminar flow tube reactor to control particle size distributions through the nucleation and growth stages. The chemistry of SOA formation from acid-catalyzed heterogeneous reactions of selected primary biogenic VOCs and their oxidation products with ozone will also be investigated. This research will help to determine the importance of monoterpene oxidation in atmospheric SOA formation and the chemical mechanisms by which this occurs (including nucleation, growth, and heterogeneous reactions). On a global scale, SOA formation is thought to be dominated by the products of reactions of biogenic organic compounds. These fine SOA particles have the potential to impact global climate, atmospheric visibility, heterogeneous chemistry, and human health. This project will also make it possible to educate a number of graduate and undergraduate students in the area of atmospheric chemistry as well as more general environmental issues.

该项目的总体目标是使用一套分析技术来阐明通过气相和非均相反应氧化选定的挥发性有机化合物（VOCs）的二次有机气溶胶（SOA）的成核和随后的生长所涉及的详细的化学和物理机制。该项目的工作将开始，首先是开发一种分析有机气溶胶微粒化学成分的新技术。这将涉及将离子阱质谱仪（ITMS）耦合到已开发用于实时粒子化学分析的热解吸粒子束质谱仪（TDPBMS）。这些TDPBMS技术，然后将与其他人一起使用，以调查SOA形成的化学反应，选定的单萜和模型化合物与臭氧，羟基自由基，硝酸根在一个大容量的环境室。在这些反应中的颗粒成核的化学将通过使用层流管反应器来控制通过成核和生长阶段的颗粒尺寸分布来研究。SOA形成的化学从选定的主要生物挥发性有机化合物和它们的氧化产物与臭氧的酸催化的非均相反应也将进行研究。这项研究将有助于确定单萜氧化在大气SOA形成的重要性和化学机制，这种情况发生（包括成核，生长和非均相反应）。在全球范围内，SOA的形成被认为是由生物有机化合物的反应产物主导的。这些细SOA颗粒有可能影响全球气候，大气能见度，异质化学和人类健康。该项目还将使一些研究生和本科生能够接受大气化学领域以及更一般的环境问题方面的教育。