Abstract Reactions between ammonia (NH3) and organic compounds containing carbonyl functional groups in aerosol particles can form organic products that are less basic than NH3 and are thus unable to neutralize efficiently nitric and sulfuric acids. In this exploratory study, the University of California, Irvine - California Institute of Technology (UCI-CIT) model is used to investigate the potential air quality impacts of including of the chemical uptake of NH3 by secondary organic aerosols (SOA) in a regional airshed model. A surface reaction of NH3 with SOA is implemented into the model to determine the impact of this process on NH3 and PM2.5 concentrations in the South Coast Air Basin of California (SoCAB). Air quality simulations are conducted using uptake coefficients ranging from 10−5 to 10−2 to explore the sensitivity of changes in NH3 and PM2.5 concentrations to the magnitude of the uptake coefficient. Results indicate that the chemical uptake of NH3 by SOA can potentially deplete gaseous NH3 concentrations, causing indirect reductions in the amount of ammonium nitrate and ammonium sulfate in particulate matter. The magnitude of the impact on NH3 and PM2.5 concentrations exhibits a strong but non-linear dependence on the value of the uptake coefficient, with evidence for small but notable impacts on air quality even with the lowest assumed uptake coefficient of 10−5.

中文翻译：

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二次有机气溶胶对氨的反应性吸收：对空气质量的影响

摘要 氨气 (NH3) 与气溶胶颗粒中含有羰基官能团的有机化合物之间的反应会形成碱性低于 NH3 的有机产物，因此无法有效中和硝酸和硫酸。在这项探索性研究中，加州大学欧文分校 - 加州理工学院 (UCI-CIT) 模型用于调查区域气域中二次有机气溶胶 (SOA) 对 NH3 化学吸收的潜在空气质量影响模型。在模型中实施了 NH3 与 SOA 的表面反应，以确定该过程对加利福尼亚南海岸空气盆地 (SoCAB) 中 NH3 和 PM2.5 浓度的影响。空气质量模拟使用范围从 10-5 到 10-2 的吸收系数进行，以探索 NH3 和 PM2.5 浓度变化对吸收系数大小的敏感性。结果表明，SOA 对 NH3 的化学吸收可能会消耗气态 NH3 浓度，从而间接减少颗粒物中硝酸铵和硫酸铵的含量。对 NH3 和 PM2.5 浓度的影响程度表现出对吸收系数值的强烈但非线性的依赖性，有证据表明即使假设最低吸收系数为 10-5，对空气质量的影响也很小但显着。导致颗粒物中硝酸铵和硫酸铵的含量间接减少。对 NH3 和 PM2.5 浓度的影响程度表现出对吸收系数值的强烈但非线性的依赖性，有证据表明即使假设最低吸收系数为 10-5，对空气质量的影响也很小但显着。导致颗粒物中硝酸铵和硫酸铵的含量间接减少。对 NH3 和 PM2.5 浓度的影响程度表现出对吸收系数值的强烈但非线性的依赖性，有证据表明即使假设最低吸收系数为 10-5，对空气质量的影响也很小但显着。