CAREER: Air-Quality Effects of Atmospheric Chlorine Chemistry

该职业奖包括实验室实验，环境测量和建模研究，以调查氯化学在环境空气中颗粒物和臭氧形成中的作用。 质谱技术的最新发展将被用来调查高度氧化的分子作为环境氯化学的结果形成。 该项目的结果可用于空气质量模型，以便对环境政策做出更明智的决策。详细的分析和测量的高度氧化的分子（HOM）在气相和颗粒相形成的不同的前体，有和没有添加氯，将在实验室中使用国家的最先进的高分辨率化学电离质谱仪（HR-CIMS）。 首席研究员假设，氯显着提高HOM，臭氧和有机颗粒物的浓度。 她还计划研究由于Cl的存在，在不同的前体和不同的实验条件下形成的硝酸烷基酯的浓度和组成的变化。 将进行环境测量，以观察Cl化学和量化石油和天然气生产区域中的含氯物质。主要研究者建议模拟实验室实验，以量化与Cl和OH反应的初始碳氢化合物的分数，以及由于与Cl或OH反应而导致的后续化学反应（例如，产物物质的持续氧化）的程度。 这将使评估的相对重要性的直接氧化氯与其影响，通过二次OH生产。她还计划开发可用于化学传输模型的参数化，以解释Cl引发的碳氢化合物氧化形成的二次有机气溶胶。

This CAREER award includes laboratory experiments, ambient measurements, and modeling studies to investigate the role of chlorine chemistry in the formation of particulate matter and ozone in ambient air. The latest developments in mass spectrometric techniques will be used to investigate the formation of highly oxidized molecules as a result of ambient chlorine chemistry. Results from this project can be used in air quality models to make better-informed decisions about environmental policies. Detailed analyses and measurements of highly oxidized molecules (HOM) in the gas and particle phases formed from different precursors, with and without the addition of Cl, will be performed in the laboratory chamber using a state-of-the-art high-resolution chemical ionization mass spectrometer (HR-CIMS). The principal investigator hypothesizes that Cl significantly enhances concentrations of HOM, ozone and organic particulate matter. She also plans to investigate changes in the concentration and composition of alkyl nitrates formed from different precursors and under different experimental conditions due to the presence of Cl. Ambient measurements will be conducted to observe Cl chemistry and quantify chlorine-containing species in an oil and gas production region. The principal investigator recommends to model laboratory chamber experiments to quantify the fraction of the initial hydrocarbon reacting with Cl versus OH, as well as the extent to which the succeeding chemistry (e.g. continued oxidation of product species) proceeds due to reaction with Cl or OH. This will enable the evaluation of the relative importance of direct oxidation by Cl versus its effect through secondary OH production. She also plans to develop parameterizations that can be used in chemical transport models to account for formation of secondary organic aerosol from Cl-initiated oxidation of hydrocarbons.