CAREER: Reactions of Volatile Organics in Aerosol Articles as a Source of Persistent Free Radicals

职业：气溶胶制品中挥发性有机物的反应作为持久自由基的来源

• 批准号: 2142825
• 负责人: Eric Vejerano
• 金额: $ 60.88万
• 依托单位: University of South Carolina at Columbia
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-01 至 2027-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2142825&HistoricalAwards=false
• 关键词: CAREER; Reactions; Volatile; Organics; Aerosol

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).WIth support from the Environmental Chemical Sciences Program in the Division of Chemistry, Eric P. Vejerano at the University of South Carolina will study the formation of environmentally persistent free radicals (EPFRs) in secondary organic aerosols (SOA). EPFRs are a recently identified class of stable and persistent pollutants that contribute to some of the adverse health effects of atmospheric particulate matter. Knowledge gaps on understanding the sources, nature, and formation of EPFRs remain, for instance, the contribution of atmospheric processing of organic contaminants in forming EPFRs. This project will investigate the formation of EPFRs when volatile organic compounds (VOCs), such as those released by plants and from human-related activities, react with atmospheric oxidants (e.g., ozone) to form particles. Also of interest are subsequent reactions that may result in the loss of EPFRs after their formation. The project will utilize a suite of analytical methods to probe changes in the particles and characterize size distributions and concentrations. The broader impacts of this project include providing knowledge of the classes of chemicals responsible for forming EPFRs, which integrates research on EPFRs with atmospheric chemistry. Concepts and results from the project will be incorporated in developing publicly accessible electronic and online educational tools for K-12 students. Additionally, this project will equip undergraduate students with scientific and technical skills through research participation and give them insight to science, technology, engineering, and mathematics (STEM) career paths. The PI seeks to cultivate excellence through diversity and is engaged in training students from groups underrepresented in chemistry. Specifically, the PI is actively training early career female and African-American students tol strengthen diversity, equity, and inclusion in chemistryresearch. The atmospheric processes leading to the conversion of VOCs to SOA are a potentially significant contributor to EPFRs, since many anthropogenic and biogenic VOCs and their oxidation byproducts have similar chemical structures to those known to form EPFRs from primary emission sources. Mass spectrometry will be used to determine chemical identities and electron paramagnetic resonance spectroscopy to measure EPFR formation and identify possible chemical structures. Diverse chemical classes of VOCs will be tested in their ability to form EPFRs using a potential aerosol mass chamber to explore structure-EPFR relationships. In addition, the impact of seed particles, temperature, irradiation, and humidity that regulate the formation and loss of EPFRs via subsequent atmospheric processes will be explored. The objectives of this career-development plan are therefore to: (1) conduct a lab-scale chamber study to understand the impact of atmospheric processes in the transformation of VOC to SOA that subsequently form EPFRs; (2) determine the factors that affect the formation and loss of EPFRs; and (3) integrate the research outcomes in implementing educational and outreach programs to improve science education on the research topic by developing electronic and online educational tools for K-12 students.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.

该奖项全部或部分由《2021 年美国救援计划法案》（公法 117-2）资助。在化学系环境化学科学项目的支持下，南卡罗来纳大学的 Eric P. Vejerano 将研究二次有机气溶胶 (SOA) 中环境持久性自由基 (EPFR) 的形成。 EPFR 是最近发现的一类稳定且持久的污染物，会导致大气颗粒物对健康产生一些不利影响。在了解 EPFR 的来源、性质和形成方面仍然存在知识差距，例如，有机污染物的大气处理对形成 EPFR 的贡献。该项目将研究当挥发性有机化合物 (VOC)（例如植物和人类相关活动释放的挥发性有机化合物）与大气氧化剂（例如臭氧）反应形成颗粒时 EPFR 的形成。同样令人感兴趣的是随后的反应可能导致 EPFR 在形成后丢失。该项目将利用一套分析方法来探测颗粒的变化并表征尺寸分布和浓度。 该项目更广泛的影响包括提供有关形成 EPFR 的化学品类别的知识，它将 EPFR 的研究与大气化学相结合。该项目的概念和结果将被纳入为 K-12 学生开发可公开访问的电子和在线教育工具中。此外，该项目将通过研究参与为本科生提供科学和技术技能，并让他们深入了解科学、技术、工程和数学 (STEM) 职业道路。 PI 致力于通过多样性培养卓越人才，并致力于培训来自化学领域代表性不足的群体的学生。 具体来说，PI 正在积极培训早期职业女性和非裔美国学生，以加强化学研究的多样性、公平性和包容性。导致 VOC 转化为 SOA 的大气过程是 EPFR 的潜在重要贡献者，因为许多人为和生物源 VOC 及其氧化副产物具有与已知从主要排放源形成 EPFR 的化学结构相似的化学结构。质谱法将用于确定化学特性，电子顺磁共振波谱法将用于测量 EPFR 的形成并确定可能的化学结构。将使用潜在的气溶胶质量室来测试不同化学类别的 VOC 形成 EPFR 的能力，以探索结构-EPFR 关系。 此外，还将探讨种子颗粒、温度、辐射和湿度通过后续大气过程调节 EPFR 形成和损失的影响。因此，该职业发展计划的目标是：(1) 进行实验室规模的室内研究，以了解大气过程对 VOC 转化为 SOA（随后形成 EPFR）的影响； (2)确定影响EPFR形成和损失的因素； (3) 将研究成果整合到实施教育和推广计划中，通过为 K-12 学生开发电子和在线教育工具来改善研究主题的科学教育。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。