RUI: Assessing Mechanisms for Organosulfate Formation in Secondary Organic Aerosol

该项目的一个主要目标是促进改进大气化学模型，这些模型对于从机制上理解与空气污染和气候变化有关的过程至关重要。这项工作的重点是研究与大气中有机硫酸盐的存在有关的二次有机气溶胶(SOA)的产生。本研究的具体目标是：(1)测定目标挥发性有机化合物(VOCs)醇衍生物的酸催化硫酸盐酯化反应速率常数；(2)研究目标挥发性有机化合物(VOCs)的硝酸盐衍生物被硫酸盐反应亲核取代硝酸盐的机理细节；(3)研究目标VOCs反应中硫酸盐自由基加成反应的机理细节，并确定模拟太阳辐射下气溶胶代理溶液的硫酸盐自由基形成机理；以及(4)合成和表征与所研究的反应相关的有机硝酸盐反应物和潜在的有机硫酸盐产物。这项研究将使所研究的各种过程的重要机理方面能够参数化，并允许确定它们在环境大气条件下的潜在重要性。这一结果将导致更准确地对SOA中有机硫酸盐的形成进行建模。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

A major goal of this project is to contribute to improving atmospheric chemical models that are critical to the mechanistic understanding of the processes that are relevant to air pollution and climate change. This effort focuses on studying the production of secondary organic aerosol (SOA) related to the presence of organosulfates in the atmosphere. This Research in Undergraduate Institutions (RUI) project will support the education and training of undergraduate students and help prepare them for future careers in science.The specific objectives of this research are to: (1) measure acid-catalyzed sulfate esterification rate constants for alcohol derivatives of targeted volatile organic compounds (VOCs); (2) investigate mechanistic details of the nucleophilic substitution of nitrate by sulfate reaction for nitrate derivatives of targeted VOCs; (3) investigate mechanistic details of sulfate radical addition to targeted olefinic VOCs reactions and identify sulfate radical formation mechanisms for aerosol proxy solutions irradiated by simulated solar irradiation; and (4) synthesize and characterize with Nuclear Magnetic Resonance (NMR) spectroscopy, organonitrate reactants and potential organosulfate products relevant to the reactions studied.This research will enable parameterization of the important mechanistic aspects of the various processes studied and allow for the determination of their potential importance under ambient atmosphere conditions. The results will lead to more accurate modeling of organosulfate formation in SOA.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.