Surface and Bulk chemistry of metals in atmospherically-relevant systems that impact climate and health

气溶胶和建筑物的大气相关表面对气候和健康的总体影响仍然不确定，因为它们具有高度复杂的物理化学性质。 国家和国际两级监管机构采用的新政策和模型需要以实验数据为基础，这些数据要考虑到这些系统在夜间和白天条件下的表面化学性质。 这些系统中的金属和有机发色团会产生活性氧，影响大气的氧化能力、建筑物的结构完整性，如果吸入，会对呼吸器官造成损害。 这些反应在降解这些大气系统中无处不在的有机物方面的重要性，以及它们在产生次生有机物和有害气相物种方面的作用知之甚少。需要在有无太阳辐射的情况下对气溶胶和建筑物的表面化学进行实验和计算研究，以便与相同化学品的体相化学进行比较。 ** 本提案所要求的资金旨在改进气候和污染物迁移模型中与大气有关的表面的参数化。 更具体地说，我们将研究在大气相关系统中普遍存在的金属的表面和体相反应之间的关键差异，对气候和健康有潜在影响。 特别是，我们的重点将是金属介导的反应及其在改性表面性质，有机材料的二次生产，和气相有机物的吸收/释放的作用。 我们将使用一套实验技术，允许在模拟大气条件的受控环境下监测这些材料表面的反应，以便将结果外推到“真实的世界”。 湿'实验将补充理论计算的细节，是很难获得实验。 研究结果将有助于制定与气溶胶对气候和健康的影响有关的未来政策，因为土地利用和工业排放的变化，以及改善气候和污染物传输模型。 我们的研究结果将与其他科学领域相关，包括光动力疗法和使用金属氧化物纳米颗粒的异质性肿瘤。

The overall impact of atmospherically-relevant surfaces of aerosols and buildings on climate and health remains uncertain due to their highly complex physicochemical properties. New policies and models used by regulators at the national and international levels need to be based on experimental data that take into account the surface chemistry of these systems under night- and day-time conditions. Metals and organic chromophores in these systems produce reactive oxygen species that impact the oxidative power of the atmosphere, structural integrity of buildings, and in case of inhalation, cause damage to the respiratory organs. Little is known about the importance of these reactions in degrading organics ubiquitous in these atmospheric systems, and their role in producing secondary organic matter and harmful gas phase species. Experimental and computational studies are needed on the surface chemistry of aerosols and buildings in the absence and presence of solar radiation for comparison with bulk phase chemistry of the same chemicals. ******The funding requested in this proposal aims at improving the parameterization of atmospherically-relevant surfaces in climate and pollutant transport models. More specifically, we will investigate key differences between surface and bulk phase reactions of metals ubiquitous in atmospherically-relevant systems with potential impacts on climate and health. In particular, our focus will be on metal-mediated reactions and their role in modifying surface properties, secondary production of organic materials, and uptake/release of gas phase organics. We will use a suite of experimental techniques that allow monitoring reactions on the surfaces of these materials under controlled environments mimicking atmospheric conditions, so that results may be extrapolated to the “real world”. The wet' experiments will be complemented with theoretical calculations of details that are hard to obtain experimentally. Results will help in shaping future policies related to aerosol impacts on climate and health due to changes in land use and industrial emissions, and improving climate and pollutant transport models. Other scientific fields for which our results will be relevant include photodynamic therapies and heterogeneous photocatalysis that use metal oxide nanoparticles.**