Direct Probing of Organic Peroxy Radical Autoxidation and Cross Reactions

该奖项由化学学部环境化学科学项目资助。华盛顿大学的乔尔·桑顿教授和他的团队研究了地球大气中活性有机碳的变化。高活性有机过氧自由基是碳基（有机）化合物在环境中降解时产生的常见物种。由于它们的反应性，检测和定量是困难的。通常只测量有机过氧自由基的总量，或者只识别早期分解产物。该项目涉及对这些物种的反应性进行新的实验室研究，提供了比以前更详细的信息。准确了解环境退化的基本途径对于确定污染物在地球环境中自然循环时会发生什么至关重要。为了了解燃料燃烧如何影响大气、水生生态系统和土壤成分，改进实验数据是必要的。该项目为化学与大气科学专业的研究生、本科生和博士后提供教育和培训机会。为了向公众介绍这项研究的结果，正在与一位纪录片制片人合作制作一部电脑动画。这部影片展示了森林中产生的有机过氧自由基如何促进大气颗粒的形成和生长。这项研究对社会很重要，因为它促进了公众健康和对天气和风暴的理解。本项目采用快流管反应器与高分辨率飞行时间和轨道rap质谱仪相结合。这些技术使研究人员能够识别并同时跟踪几乎所有的有机过氧自由基及其交叉反应产物。一组相关的起始化合物（商业购买或合作者合成）的反应跟踪作为反应时间的函数完成。这些实验提供了在典型环境条件下气相有机碳降解速率和产物的定量见解。同位素标记和竞争性反应物实验允许测试假设的反应机制和独立的速率量化。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is supported by the Environmental Chemical Sciences Program of the Division of Chemistry. Professor Joel Thornton of the University of Washington and his group investigate what happens to reactive organic carbon species in the Earth's atmosphere. The highly reactive organic peroxy radicals are common species produced when carbon-based (organic) compounds degrade in the environment. Their detection and quantification is difficult because of their reactivity. Often only a total of organic peroxy radicals are measured, or only early decomposition products are identified. This project involves novel laboratory studies of the reactivity of these species which provides more detailed information than previously possible. An accurate understanding of the fundamental pathways of environmental degradation is crucial to determining what happens to pollutants as they naturally cycle through the Earth's environment. Improved experimental data are necessary for understanding how fuel combustion impacts the atmosphere, aquatic ecosystems, and soil composition. The project provides educational and training opportunities for graduate students, undergraduates in chemistry and atmospheric sciences, and a postdoctoral research fellow. To inform the public of the results of this research, a computer animation is being produced in collaboration with a documentary filmmaker. This film shows how organic peroxy radicals produced in forests contribute to atmospheric particle formation and growth. This research is important to society as it promotes public health and understanding of weather and storms.This project uses fast flow tube reactors coupled to high resolution time of flight and orbitrap mass spectrometers. These techniques allow researchers to identify and simultaneously track nearly all individual organic peroxy radicals and their cross-reaction products. Reaction tracking of a suite of relevant starting compounds, purchased commercially or synthesized by collaborators, is done as a function of reaction time. These experiments provide quantitative insights into the rates and products of gas-phase organic carbon degradation under typical environmental conditions. Isotopic labeling and competitive reactant experiments allow for tests of hypothesized reaction mechanisms and independent rate quantification.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.