Atmospheric Chemistry of Low Volatility Organic Compounds

低挥发性有机化合物的大气化学

• 批准号: 9900404
• 负责人: Mario Molina
• 金额: $ 14.5万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2000-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9900404&HistoricalAwards=false
• 关键词: Atmospheric; Chemistry; Low; Volatility; Organic

The objective of the proposed research is to improve the understanding of the chemical and microphysical properties of atmospheric organic aerosols. These aerosols play important roles in the atmosphere: their impacts range from human health effects in urban and regional air pollution to scattering of solar radiation in climate change.The work proposed here is designed to provide quantitative measurements on heterogeneous chemical processes involving prototype low volatility organic compounds. The technique to be employed utilizes a low pressure flow tube with a moveable injector coupled to a chemical ionization mass spectrometer for analysis of gaseous reactants and products; the low volatility organic reactants will be deposited as films on the flow tube surface. The composition of the films will be monitored by infrared and/or Raman spectroscopy.Specific projects to be carried out include investigations of the reactions of the low volatility organic species with OH, O2, NO and NO2, to be injected into the flow tube sequentially and/or simultaneously. The organic species to be studied are alkanes, polycyclic aromatic hydrocarbons (PAHs) and acids. The reaction of isoprenoids with ozone will also be studied. The hygroscopic behavior of the organic films will be investigated before and after exposure to the various gaseous reactants by monitoring the uptake of water vapor. Furthermore, the adsorption properties of the various types of organic compounds under study will be investigated on several different substrates.

拟议研究的目的是提高对大气有机气溶胶的化学和微物理特性的认识。 这些气溶胶在大气中起着重要的作用：它们的影响范围从城市和区域空气污染对人类健康的影响到气候变化中太阳辐射的散射，这里提出的工作旨在提供定量测量涉及原型低挥发性有机化合物的多相化学过程。 所采用的技术利用低压流管，其具有耦合到化学电离质谱仪的可移动注射器，用于分析气态反应物和产物;低挥发性有机反应物将作为膜沉积在流管表面上。 薄膜的组成将通过红外和/或拉曼光谱进行监测。要进行的具体项目包括研究低挥发性有机物质与OH、O2、NO和NO2的反应，这些物质将依次和/或同时注入流管。 要研究的有机物种是烷烃、多环芳烃和酸。 还将研究类异戊二烯与臭氧的反应。在暴露于各种气态反应物之前和之后，通过监测水蒸气的吸收来研究有机膜的吸湿行为。 此外，研究中的各种类型的有机化合物的吸附性能将在几种不同的基板上进行研究。