The Importance of Organic Nitrates as Sinks for Atmospheric Nitrogen Oxides

有机硝酸盐作为大气氮氧化物汇的重要性

• 批准号: 9520374
• 负责人: Paul Shepson
• 金额: $ 37.29万
• 依托单位: Purdue Research Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-01-15 至 1999-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9520374&HistoricalAwards=false
• 关键词: Importance; Organic; Nitrates; Sinks; Atmospheric

9520374 Shepson This project aims at improving our understanding of the impact of organic nitrates on the production and distribution of tropospheric ozone. Organic nitrates are produced in the reaction between organic peroxy radicals with nitric oxide, usually as a minor product. The importance of this reaction channel increases with the size of the organic precursor. Removal of nitric oxide through this reaction could constitute an important NOx sink, thus reducing the ozone formation rate. In order to accurately model the ozone budget, the yields of organic nitrates in the oxidation pathways of natural hydrocarbons are needed. In this project, the yield of nitrate formation from isoprene, terpenes, and aromatic hydrocarbons will be measured using a large photochemical reaction chamber equipped with sampling and detection devices capable of distinguishing individual nitrate species. In addition, ambient measurements of organic nitrates will be conducted at a forested site at the northwestern tip of the Michigan southern Peninsula, using a unique combination of adsorbent concentration and chemiluminescent detection that will enable the investigators to measure the total concentration of both gas- and particulate-phase organic nitrates with very low limits of detection. These data will be useful for modeling studies of tropospheric ozone, and will provide new insights into the problem of the speciation of atmospheric total reactive nitrogen (NOy), and the importance of organic nitrates as a sink and/or vehicle for the transport of atmospheric NOx.

9520374谢普森该项目旨在增进我们对有机硝酸盐对对流层臭氧的产生和分布的影响的了解。有机硝酸盐是在有机过氧基与一氧化氮反应中生成的，通常是次要产物。该反应通道的重要性随着有机前驱体的大小而增加。通过这个反应去除一氧化氮可能会构成一个重要的NOx汇，从而降低臭氧的形成速度。为了准确地模拟臭氧收支，需要计算天然碳氢化合物氧化途径中有机硝酸盐的产额。在本项目中，将使用配备能够区分单个硝酸盐物种的采样和检测设备的大型光化学反应室来测量异戊二烯、萜烯和芳香烃形成硝酸盐的产率。此外，将在密歇根南部半岛西北端的一个森林地点对有机硝酸盐进行环境测量，使用吸附剂浓度和化学发光检测的独特组合，使调查人员能够以非常低的检测下限测量气相和颗粒相有机硝酸盐的总浓度。这些数据将有助于对流层臭氧的模拟研究，并将为大气总反应氮(NOY)的形态问题以及有机硝酸盐作为大气NOx输送的汇和/或载体的重要性提供新的见解。