Characterization of Secondary Organic Aerosol Exposed to Acidic Sulfates: Chamber and Field Studies

暴露于酸性硫酸盐的二次有机气溶胶的表征：室内和现场研究

• 批准号: 0852747
• 负责人: Myoseon Jang
• 金额: $ 52.77万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0852747&HistoricalAwards=false
• 关键词: Characterization; Secondary; Organic; Aerosol; Exposed

This project addresses the hypothesis that acidic sulfates have a significant impact on secondary organic aerosol (SOA) formation in the atmosphere via heterogeneous reactions that form nonvolatile products including organic sulfates (OS). The major goals are (1) to develop new analytical techniques to measure aerosol acidity and bulk phase products; (2) to elucidate the mechanism of SOA formation in multicomponent organic and inorganic mixtures; and (3) to evaluate the impact of acidic sulfates on SOA formation in ambient air. Organic compounds found in the atmosphere will be exposed to acidic sulfate solutions to imitate heterogeneous chemistry in acidic aerosols. Teflon chambers will be used to expose organic compounds to submicron acidic sulfate aerosols and to perform a wide range of SOA experiments. Various spectroscopic methods will be used to analyze the aerosol bulk phase products. A new technique will be developed to dynamically measure aerosol acidity using colorimetry coupled with reflectance UV-Visible spectrometry (C-RUV). The results obtained from the laboratory studies will then be applied to field data to evaluate the impact of acidic sulfate on organic carbon. A new predictive model will be developed to quantify the role of heterogeneous chemistry in SOA formation and growth.This study will help to explain how heterogeneous reactions change the chemical properties of atmospheric aqueous droplets, such as those in clouds, and how they affect aerosol optical properties. It also has implications for visibility and public health. Broader impacts also include support for a diverse group of graduate and undergraduate students. This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

本项目提出了酸性硫酸盐通过非均相反应形成包括有机硫酸盐（OS）在内的非挥发性产物对大气中二次有机气溶胶（SOA）形成产生重大影响的假设。 主要目标是（1）开发新的分析技术来测量气溶胶酸度和体相产物;（2）阐明多组分有机和无机混合物中SOA形成的机制;（3）评估酸性硫酸盐对环境空气中SOA形成的影响。 大气中发现的有机化合物将暴露于酸性硫酸盐溶液中，以模拟酸性气溶胶中的非均相化学。 特氟隆室将用于将有机化合物暴露于亚微米酸性硫酸盐气溶胶中，并进行广泛的SOA实验。 将使用各种光谱方法来分析气溶胶体相产物。 本文提出了一种新的气溶胶酸度动态测量技术--比色法与反射紫外-可见光谱法（C-RUV）联用。 实验室研究的结果将应用于现场数据，以评估酸性硫酸盐对有机碳的影响。 一个新的预测模型将被开发来量化SOA的形成和增长的非均相化学的作用，这项研究将有助于解释非均相反应如何改变大气中的水滴的化学性质，如那些在云中，以及它们如何影响气溶胶的光学特性。 它还对能见度和公共卫生产生影响。 更广泛的影响还包括支持不同群体的研究生和本科生。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。