Surface and Bulk Diffusion on Single-Crystal Ice and Acid Hydrate Multilayers

单晶冰和酸水合物多层膜上的表面和体扩散

• 批准号: 9528473
• 负责人: Steven George
• 金额: $ 30.5万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-03-01 至 2000-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9528473&HistoricalAwards=false
• 关键词: Surface; Bulk; Diffusion; Single; Crystal

The investigation of the diffusion of small, atmospherically relevant molecules on and in ice is the subject of this research project supported jointly by the Analytical and Surface Chemistry Program and the Atmospheric Chemistry Program. Laser resonant desorption methods will be used to probe the diffusion of ClONO2, HOCl, HNO3 and HCl on the surface and in the bulk of ice and acid hydrate multilayers produced and characterized in an ultra high vacuum apparatus. An understanding of the diffusion process and a knowledge of diffusion rates is important to developing an understanding of the heterogeneous chemistry of polar stratospheric clouds that convert stable halogen containing reservoir molecules into active halogen species which destroy ozone catalytically in the stratosphere. This work will also provide new basic information about the diffusion process on and in molecular solids. In order to understand the detailed mechanisms and rates of stratospheric ozone depletion by man made chemicals such as chlorofluorocarbon propellants and refrigerants, it is important to know about the rates and mechanisms of diffusion of these molecules and their decomposition products on the surfaces and in the bulk of the ice particles which exist in the stratosphere. Obtaining this understanding is the goal of this research project. Using laser desorption methods developed previously by the principal investigator, the details of this diffusion process will be examined. This information will help in developing models of the chemistry of the atmosphere which will aid scientists in proposing solutions for problems such as the depletion of the ozone layer in the stratosphere.

对与大气有关的小的 冰上和冰中的分子是这个研究项目的主题， 由分析和表面化学计划和 大气化学计划。 激光共振解吸方法将是 用于探测ClONO2、HOCl、HNO3和HCl在表面上的扩散 在大量的冰和酸水合物多层中， 其特征在于一种超高真空装置。 的理解 扩散过程和扩散率的知识是重要的， 了解极性化合物的非均相化学 平流层云转化稳定的含卤素水库 分子转化为活性卤素物种，催化破坏臭氧 在平流层。 这项工作还将提供新的基本信息 关于分子固体上和分子固体中的扩散过程。 为了了解平流层大气中的大气环流的详细机制和速率 人造化学品如含氯氟烃对臭氧层的破坏 推进剂和制冷剂，重要的是要知道的速度和 这些分子的扩散机制及其分解 存在于冰粒表面和大部分冰粒中的产物 在平流层。 获得这种理解是本组织的目标， 研究项目。 使用激光解吸方法， 首席研究员，这个扩散过程的细节将是 考察 这些信息将有助于开发 这将有助于科学家提出 臭氧层消耗等问题的解决办法， 平流层