RUI: Chemical Characterization and Reactivity of Chromophoric Dissolved Organic Matter (CDOM) in Rainwater

RUI：雨水中发色溶解有机物 (CDOM) 的化学表征和反应性

• 批准号: 0646153
• 负责人: Robert Kieber
• 金额: --
• 依托单位: University of North Carolina at Wilmington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0646153&HistoricalAwards=false
• 关键词: RUI; Chemical; Characterization; Reactivity; Chromophoric

This project addresses the questions: (1) What are the origin and chemical characteristics of chromophoric dissolved organic matter (CDOM) in rainwater? (2) What is CDOM's role in photochemical transformations? (3) What is CDOM's involvement in metal speciation? These questions will be studied with a variety of tools including isotopic analysis, NMR, and controlled photolysis experiments. For the analyses, rainwater CDOM samples will be collected during different seasons, storm types, and locations. The rates and quantum yields for the formation of hydrogen peroxide and other small molecules will be determined with photolysis experiments. The contribution of CDOM nitrogen to dissolved organic nitrogen in rainwater will also be assessed. This research will provide new information on the chemical and physical factors influencing sources, fate, and atmospheric impacts of rainwater CDOM, which may be the predominant form of carbon in precipitation. CDOM photochemistry affects the spectral attenuation of solar radiation, tropospheric free radical chemistry, oxidizing capacity, acid generating capacity, and trace metal speciation in the atmosphere. Broader impacts also include education and training of a post-doctoral researcher, two master's level graduate students, two undergraduates and one high school student each year. In addition, a local high school science teacher will participate in this research for one month each year.

本项目主要研究以下问题：（1）雨水中有色溶解性有机物（CDOM）的来源和化学特征是什么？(2)CDOM在光化学转化中的作用是什么？(3)CDOM在金属形态方面的参与是什么？ 这些问题将研究与各种工具，包括同位素分析，核磁共振，和受控的光解实验。 为了进行分析，将在不同的季节、风暴类型和地点收集雨水CDOM样本。 过氧化氢和其他小分子形成的速率和量子产率将通过光解实验来确定。 还将评估CDOM氮对雨水中溶解有机氮的贡献。 这项研究将提供新的信息的化学和物理因素影响的来源，命运和大气的影响，雨水CDOM，这可能是主要形式的碳在降水中。 CDOM光化学影响太阳辐射的光谱衰减、对流层自由基化学、氧化能力、产酸能力和大气中痕量金属形态。 更广泛的影响还包括每年教育和培训一名博士后研究员、两名硕士研究生、两名本科生和一名高中生。 此外，一名当地高中科学教师每年将参加这项研究一个月。