Development of Photofragmentation Laser Induced Fluorescence Sensor for Measurements of CH31 in the Marine Boundary Layer

开发用于测量海洋边界层中 CH31 的光碎裂激光诱导荧光传感器

• 批准号: 9807653
• 负责人: Scott Sandholm
• 金额: $ 24万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9807653&HistoricalAwards=false
• 关键词: Development; Photofragmentation; Laser; Induced; Fluorescence

This award in the Environmental Geochemistry and Biogeochemistry Program is jointly supported by the Divisions of Atmospheric Science and Chemistry and by the MPS Office of Multidisciplinary Activities. Dr. Scott T. Sandholm of the School of Earth and Atmospheric Sciences, Georgia Institute of Technology, will develop a photofragmentation laser induced fluorescence sensor (PF-LIF) to measure volatile methyl iodide in situ in the marine boundary layer. Current detection methods for organic iodides rely heavily on analysis of stored `grab` samples and can be quite sensitive to preparation and handling of samples and to thermal degradation. The LIF sensor will permit in situ measurements as well as temporal emission profiles of methyl iodide and other simple organic iodides to the atmosphere from oceanic and coastal regions. The method is expected to have the sensitivity and selectivity needed to be effective. The similarities in photofragmentation dynamics of organic iodides enables total iodine emission to be measured by following the cumulative photofragmented production of atomic iodine as I* for all organic iodides known to be emitted from oceanic sources. The role of iodine in tropospheric and stratospheric ozone cycles is not well understood due to lack of quantitative measurements of the source compounds. Organic iodide compounds are thought to evaporate from the ocean and serve as a source. In this research, a new method for direct measurement of iodine will be developed and tested in field deployment off the coast of Georgia.

该奖项属于环境地球化学和生物地球化学项目，由大气科学和化学处以及公安部多学科活动办公室共同支持。 佐治亚理工学院地球与大气科学学院的 Scott T. Sandholm 博士将开发一种光碎裂激光诱导荧光传感器 (PF-LIF)，用于原位测量海洋边界层中的挥发性碘甲烷。 目前的有机碘化物检测方法严重依赖于对存储的“抓取”样品的分析，并且对样品的制备和处理以及热降解非常敏感。 LIF传感器将允许原位测量以及甲基碘和其他简单有机碘化物从海洋和沿海地区到大气中的时间排放曲线。 该方法预计具有有效所需的灵敏度和选择性。 有机碘化物的光碎裂动力学的相似性使得可以通过跟踪已知从海洋源排放的所有有机碘化物的原子碘的累积光碎裂产量（I*）来测量总碘排放量。 由于缺乏对源化合物的定量测量，碘在对流层和平流层臭氧循环中的作用尚不清楚。有机碘化物被认为是从海洋中蒸发并作为来源。 在这项研究中，将开发一种直接测量碘的新方法，并在乔治亚州海岸外的现场部署进行测试。