Fundamental Studies of Heterogeneous Processes of Atmospheric Importance

过去对大气化学的研究主要是 关于“同质”化学过程发生在 微量的气态物质。 少得多 已经注意到“异质”过程， 这些物理和化学过程发生在，或 跨越固体、液体或气体介质之间的边界。 大气科学家越来越意识到， 然而，异质过程发挥着重要作用， 在自然界和 污染的大气层。 最近的一个例子是， 极地冰粒的非均相化学 平流层云在南极春季的枯竭 臭氧 该项目将测量气体的质量容纳 物种，如二甲硫醚和有机过氧自由基， 表面，包括含碳烟灰材料，硫酸， 还有海盐 气体和表面反应产物将 通过质谱法和热脱附测定。 这些 实验的目的是产生所需的数据， 化学转化的数学模型 对流层，特别是在高气溶胶负荷的地区。

Past research in atmospheric chemistry has been largely concerned with "homogeneous" chemical processes occurring among gaseous substances occurring in trace amounts. Much less attention has been given to "heterogeneous" processes, defined as those physical and chemical processes occurring at, or across, boundaries between the solid, liquid, or gaseous media. There is a growing awareness among atmospheric scientists, however, that the heterogeneous processes play important roles in chemical transformations occurring in both natural and polluted atmospheres. A recent example is the crucial role of heterogeneous chemistry on the ice particles of polar stratospheric clouds in the depletion of springtime Antarctic ozone. This project will measure mass accommodation of gaseous species, such as dimethysulfide and organoperoxy radicals, on surfaces, including carbonaceous soot material, sulfuric acid, and sea salt. Gaseous and surface reaction products will be determined by mass spectrometry and thermal desorption. These experiments are designed to yield data required for developing mathematical models of chemical transformations in the troposphere, especially in regions of high aerosol loadings.