Tropospheric Reactions of Sea Salt Particles: The Role of Surface Water

该项目扩展了以前的工作，以了解海盐气溶胶的详细表面化学。特别是氯化镁在影响表面性质方面的作用，将作为相对湿度的函数加以研究。目标将是对与大气有关的条件下涉及海盐颗粒的反应的机制和动力学进行定量了解，以便将这些过程准确地纳入大气化学过程的数值模型。将使用许多分析工具，包括漫反射红外傅立叶变换光谱（DRIFTS）和质谱的组合，这将允许同时测量气相和凝聚相产物。此外，气溶胶将在反应室中产生，并使用长路径傅立叶变换光谱（LP-FTIR），紫外光谱区微分光学吸收光谱（DOAS）和大气压电离质谱（API-MS）进行观察。这些活动的更广泛影响包括改进将纳入海洋边界层大气化学数值模式的过程的量化；为本科生和研究生（包括来自代表性不足群体的学生）以及早期职业科学家提供教育和培训机会；以及面向K-12学生和公众的推广活动。该项目由大气化学、分析化学和表面化学项目联合支持。

This project extends previous work to understand the detailed surface chemistry of sea salt aerosols. In particular the role of magnesium chloride in influencing the nature of the surface will be studied as a function of relative humidity. The goal will be to develop quantitative understanding of the mechanisms and kinetics of reactions involving sea salt particles under conditions relevant to the atmosphere in order that such processes can be accurately incorporated into numerical models of atmospheric chemical processes. A number of analytical tools will be used including the combination of diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and mass spectrometry, which will allow measurement of gas and condensed phase products simultaneously. In addition, aerosols will be generated in a reaction chamber with observations made using long path Fourier transform spectroscopy (LP-FTIR), differential optical absorption spectroscopy (DOAS) in the ultraviolet spectral region, and atmospheric pressure ionization mass spectrometry (API-MS).Broader impacts of these activities include improved quantification of processes to be incorporated into numerical models of atmospheric chemistry in the marine boundary layer; education and training opportunities for undergraduate and graduate students (including those from underrepresented groups) and early career scientists; as well as outreach activities to K-12 students and to the public. This project is supported jointly by the Atmospheric Chemistry and Analytical and Surface Chemistry Programs.