AGS-PRF: Peroxy Radical (RO2) Reactivity through Functionalized Organic Iodides

AGS-PRF：通过功能化有机碘化物实现过氧自由基 (RO2) 反应

• 批准号: 2032211
• 金额: $ 19万
• 依托单位: Rivera-Rios, Jean C
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-03-01 至 2023-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2032211&HistoricalAwards=false
• 关键词: AGS; PRF; Peroxy; Radical; RO2

This project involves laboratory experiments to better characterize the reactive chemistry of peroxy radicals in the atmosphere. Peroxy radicals are key intermediate species in the production of secondary organic aerosol and ozone, which are detrimental to human health and affect climate. A flow tube will be used in the laboratory to study peroxy radical reactions under many different environmental conditions. A better understanding of this chemistry has implications for modeling air quality and for informing policy decisions on mitigating air pollution levels that may be harmful to human health.The objectives of this research are: (1) to determine the effects of molecular structure and degree of functionalization on isomerization rates and dimerization products of peroxy radicals (RO2); (2) to determine the organic nitrate yield and alkoxy radical fate of functionalized RO2 species; and (3) to determine the branching ratio of hydroperoxides (ROOH) and OH in RO2-HO2 reactions where the RO2 radical is functionalized. The first objective involves probing RO2 unimolecular reactions and RO2-RO2 reactivity and determining the relative importance of each process. The second objective includes probing RO2-NO reactivity and evaluating the relative rates between these reactions and the isomerization reactions described in the Objective 1. The third objective will help to assess the hypothesis that the yield of OH increases as the degree of functionalization increases in RO2- HO2 reactions. In clean environments, where bimolecular lifetimes are long, multiple isomerization reactions might lead to RO2 species that are very functionalized and more likely to yield OH when reacting with HO2 than to form peroxides. The results from these experiments will provide fundamental experimental data on isomerization rates and branching ratios of bimolecular reactions of RO2 necessary to understand atmospheric oxidation. The success of this research will lead to the improved modeling of oxidation processes, under the conditions of both “high” and “low" NOx environments, thereby helping to improve predictions of both air quality and climate change.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该项目涉及实验室实验，以更好地表征大气中过氧自由基的反应性化学。过氧自由基是二级有机气溶胶和臭氧产生的关键中间物种，这些物种对人类健康有害并影响气候。在许多不同的环境条件下，将在实验室中使用流动管来研究过氧自由基反应。对这种化学的更好理解对建模空气质量并为减轻可能有害人类健康有害的空气污染水平的政策决策提供了影响。这项研究的目标是：（1）确定分子结构和功能化程度对异构化速率和过氧辐射二聚体产物的影响（RO2）； （2）确定功能化的RO2物种的有机硝酸盐产量和烷基自由基脂肪； （3）确定氢过氧化物（ROOH）的分支比和OH在RO2-HO2反应中，其中RO2自由基被官能化。第一个目标涉及探测RO2单分子反应和RO2-RO2反应性，并确定每个过程的相对重要性。第二个目标包括探测RO2-NO反应性，并评估这些反应之间的相对速率和目标1中所述的异构反应。第三个目标将有助于评估假说，即随着RO2-HO2反应的官能化程度的增加，OH的产量增加。在双分子寿命长的清洁环境中，多个异构化反应可能导致RO2物种功能齐全，并且在与HO2反应时更可能产生OH，而不是形成过氧化物。这些实验的结果将提供有关理解大气氧化所必需的RO2双分子反应的异构化率和分支比的基本实验数据。这项研究的成功将导致在“高”和“低” NOX环境的条件下改善氧化过程的建模，从而有助于改善对空气质量和气候变化的预测。该奖项反映了NSF的法定任务，并被认为是使用该基金会的知识分子和更广泛的影响来评估CRITEIA CRITERIA CRITERIA的评估。