Microstructural Pathway of EPFR Formation and their Decay Mechanisms

EPFR形成的微观结构途径及其衰变机制

基本信息

批准号：
10116410
负责人：
Phillip Sprunger
金额：
$ 26.16万
依托单位：
LOUISIANA STATE UNIV A&M COL BATON ROUGE
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-08-15 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10116410
关键词：
Address Adsorption Affect Air Biochemical Charge Chemicals Chemistry Complex Computing Methodologies Dangerousness Degradation Pathway Dependence Development Dust Ecology Electron Transport Electrons Environment Environmental Risk Factor Exposure to Free Radical Formation Free Radicals Generations Goals Hazardous Substances Hazardous Waste Hazardous Waste Sites Health Humidity Individual Joints Knowledge Laboratories Longevity Magnetic Resonance Metals Methods Microscopic Minerals Modeling Molecular Neutrons Oxidation-Reduction Oxides Particulate Matter Pathway interactions Photochemistry Photons Powder dose form Prevention Prevention strategy Process Production Property Radiation Reactive Oxygen Species Research Research Personnel Risk Assessment Roentgen Rays Route Sampling Signal Recognition Particle Soil Soot Spectrum Analysis Structure Superfund Surface System Techniques Temperature Toxic effect Translating Ultrafine Variant Work base clay computer studies design electronic structure experimental study fly ash insight interfacial man metal oxide nanocluster nanoparticle oxidation particle pollutant programs remediation superfund site trend vibration

项目摘要

Project Summary/Abstract: Project 5 There is strong evidence that environmentally persistent free radicals (EPFRs) associated with partic- ulate matter (PM) and soils found in/around declared and potential Superfund sites pose adverse health effects. Mitigation of the associated environmental risks requires a detailed understanding of EPFR-contaminated air and soil systems. Specifically, Project 5 is in direct alignment with SRP Man- date 4, which is elucidating chemical and physical methods to reduce the amount and toxicity of these hazardous substances. Project 5 will study the microscopic, or atomistic, properties of EPFR for- mation, including their remarkable stability in the environment, and will model the resulting influences of chemical decay on a broad base of metal oxide (MO) platforms. Employing a toolbox of state-of- the-art experimental and molecular ab initio computational methods across differing material plat- forms (surfaces, nanoclusters/powders, clays, EPA fly ash, soil), our continued focus is on elucidating individual details of and corresponding local effects (electronic/chemical/atomic structure) on organic molecular-metal oxide/center chemisorption, ensuing charge transfer (redox), and consequent chemi- cal degradation pertinent to EPFR-containing systems such as PM, powders, clays, and real-world (field EPFR) materials. Our Aims focus on answering three simple questions at an atomistic level: 1) How do EPFRs chemically form? 2) What causes EPFR decay? and 3) Why are EPFR properties simi- lar across differing platforms? While our previous efforts have elucidated trends in EPFR formation, the connection between EPFR decay mechanisms, lifetimes, and dependence on MO—the path to destabilization/remediation (SRP Mandate 4)—has not yet been addressed and is a main goal of our project. Although focused primarily on revealing fundamental environmental science, our Project will work symbiotically with the Center. By identifying material factors from our other SRP Projects and correlating results across differing material platforms, we will obtain synergistic/antagonistic tendency parameters for EPFR destabilization/remediation that translate to other Projects, and in turn, initiate and clarify mitigation and remediation strategies. By employing experimental processes that both model and recapitulate real world exposures, Project 5 will provide a picture of the microscopic sys- tems generating the EPFRs and related adsorbate systems, but more importantly, will interrogate ef- fects that promote/hinder degradation and the corresponding products that influence and enhance activities across the Center (Projects 1–4 and all the Cores). Integrating closely with and expanded by Project 4, this will allow our Center to synergistically elucidate the atomic mechanisms of the EPFR chemistry in a scalable and predictive manner that contributes to understanding biochemical health effects, mitigation, and remediation of these particle-bound pollutants at Superfund sites.

项目总结/摘要：项目 5 有强有力的证据表明环境持久性自由基 (EPFR) 与颗粒物相关在已宣布的和潜在的超级基金地点内/周围发现的物质（PM）和土壤造成不利影响减轻相关的环境风险需要详细了解具体来说，项目 5 与 SRP Man- 受 EPFR 污染的空气和土壤系统直接一致。日期 4，阐明了减少这些物质的数量和毒性的化学和物理方法项目 5 将研究 EPFR 的微观或原子特性：化，包括它们在环境中的显着稳定性，并将模拟由此产生的影响使用状态工具箱在广泛的金属氧化物（MO）平台上进行化学衰变。跨不同材料平台的最先进的实验和分子从头计算方法形式（表面、纳米团簇/粉末、粘土、EPA 飞灰、土壤），我们持续关注的是阐明有机物的个别细节和相应的局部影响（电子/化学/原子结构）分子金属氧化物/中心化学吸附，随后发生电荷转移（氧化还原），以及随后的化学反应与含有 EPFR 的系统（例如 PM、粉末、粘土和现实世界）相关的钙降解（EPFR 领域）材料我们的目标集中于在原子层面回答三个简单的问题：1) EPFR 是如何化学形成的？ 2) EPFR 衰减的原因是什么？ 3) 为什么 EPFR 的特性相似？虽然我们之前的努力已经阐明了 EPFR 形成的趋势， EPFR 衰变机制、寿命和对 MO 的依赖性之间的联系——通往不稳定/补救（SRP 指令 4）——尚未得到解决，这是我们的主要目标尽管我们的项目主要侧重于揭示基础环境科学，但我们将通过识别我们其他 SRP 项目的物质因素，与中心共生。将不同材料平台的结果关联起来，我们将获得协同/拮抗趋势 EPFR 不稳定/补救的参数可转化为其他项目，进而启动并通过采用实验过程来阐明缓解和补救策略。模型并重述现实世界的暴露，项目 5 将提供微观系统的图片生成 EPFR 和相关吸附物系统的技术，但更重要的是，将询问 ef- 促进/阻碍降解的效应以及影响和增强的相应产物整个中心的活动（项目 1-4 和所有核心）紧密结合并由其扩展。项目 4，这将使我们中心能够协同阐明 EPFR 的原子机制以可扩展和预测的方式研究化学，有助于了解生化健康这些颗粒结合污染物在超级基金站点的影响、缓解和修复。