Oxidation Pathways and Radicals at the Gas-Particle Interface Using Surface-Sensitive Techniques

使用表面敏感技术研究气体-颗粒界面处的氧化途径和自由基

• 批准号: 2331523
• 负责人: Lisa Wingen
• 金额: $ 77.2万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-02-15 至 2027-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2331523&HistoricalAwards=false
• 关键词: Oxidation; Pathways; Radicals; Gas; Particle

In this project, the Principal Investigator (PI) suggests studying secondary organic particle oxidation mechanisms via new approaches paired with established approaches. These novel analytical techniques include Matrix Assisted Ionization Mass Spectrometry (MAI-MS) and Easy Ambient Sonic-spray Ionization Mass Spectrometry (EASI-MS) which enable direct measurements of organic particle surfaces. This work builds upon previously developed measurement techniques in order to study the surface-level processes that impact organic aerosol oxidation, which is a known knowledge gap. Success in this project will fill this gap and could result in potentially transformative improvements to our understanding of aerosol processes and atmospheric chemistry. This project includes support for a postdoctoral researcher as well as graduate and undergraduate students and includes extensive community education and outreach.These techniques will be applied before and after heterogeneous hydroxy radical oxidation of organic particles via three specific objectives: (1) the elucidation of the universality and sensitivity of the formation of peroxides and other surface-bound products to reactant structures and oxidant concentrations using MAI-MS and EASI-MS techniques; (2) the direct observations of organic radicals in highly viscous model particles using spin trap compounds and the indirect determination of peroxy radical fate in the presence of nitrogen oxide; (3) the determination of which products that result from complex aromatic oxidations can be measured via uptake onto solid organic matrix particles.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.

在该项目中，首席研究员 (PI) 建议通过新方法与现有方法相结合来研究二次有机颗粒氧化机制。这些新颖的分析技术包括基质辅助电离质谱 (MAI-MS) 和简易环境声波喷雾电离质谱 (EASI-MS)，可直接测量有机颗粒表面。这项工作建立在先前开发的测量技术的基础上，以便研究影响有机气溶胶氧化的表面过程，这是一个已知的知识差距。该项目的成功将填补这一空白，并可能为我们对气溶胶过程和大气化学的理解带来潜在的变革性改进。该项目包括对博士后研究员以及研究生和本科生的支持，并包括广泛的社区教育和推广。这些技术将通过三个具体目标在有机颗粒的非均相羟基自由基氧化之前和之后应用：（1）阐明使用 MAI-MS 和 EASI-MS 技术，过氧化物和其他表面结合产物的形成对反应物结构和氧化剂浓度的普遍性和敏感性； (2) 使用自旋陷阱化合物直接观察高粘性模型颗粒中的有机自由基，并间接测定氮氧化物存在下的过氧自由基命运； (3) 确定哪些由复杂芳香族氧化产生的产物可以通过固体有机基质颗粒的吸收来测量。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。