权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

MRI: Acquisition of a Chemical Ionization Mass Spectrometer and a High-Resolution Time of Flight Aerosol Mass Spectrometer for Organic Aerosol Oxidation Studies

MRI：购买化学电离质谱仪和高分辨率飞行时间气溶胶质谱仪用于有机气溶胶氧化研究

基本信息

批准号：
0922643
负责人：
Neil Donahue
金额：
$ 49万
依托单位：
Carnegie-Mellon University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2009
资助国家：
美国
起止时间：
2009-09-01 至 2011-02-28
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0922643&HistoricalAwards=false
关键词：
MRI Acquisition Chemical Ionization Mass

项目摘要

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."0922643DonahueResearchers in the Carnegie Mellon University Center for Atmospheric Particle Studies (CAPS) will acquire two instruments in order to probe the complex interactions between gas-phase organic oxidation chemistry and the evolution of organic particulate matter (PM). One instrument is a Chemical Ionization Mass PSpectrometer (CIMS) designed for flexible, highly sensitive measurement of critical radicals (OH, HO2, and RO2), sulfuric acid vapor, or ammonia. The radical levels control the rate as well as the mechanisms for oxidation of organic compounds in the atmosphere; ammonia and sulfate, along with organics, are critical players in new-particle formation and grown in the atmosphere. The other instrument is a High-Resolution Time of Flight Aerosol Mass Spectrometer (HR-AMS), with a mass resolution of 5000 (_0.02 amu). The HR-AMS will measure the size-dependent non-refractory fraction of particle composition between 50 and 700 nm, explicitly resolving C:H:O:N:S in the particles. With a light-scattering module to detect individual particles, the HR-AMS will be able to detect single particles, enabling experiments addressing the evolving mixing state of aerosols from different sources.Taken together, these instruments will permit research at the forefront of atmospheric chemistry. Organic aerosols are a dynamic system, combining phase partitioning between the gas and particulate phases with oxidation chemistry, which causes the volatility distribution of organic material associated with atmospheric particles to evolve continuously over their roughly week-long residence time in the atmosphere. Concurrently, the state-of-the-art in condensed-phase measurements is evolving rapidly, so that it is now possible to measure the molecular formula of most fragments observed in an organic mass spectrum. The HR-AMS will thus enable measurements of the oxidation state of organic particulate matter as it evolves due to gas-phase oxidation reactions.

“该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。卡内基梅隆大学大气颗粒研究中心（CAPS）的研究人员将获得两台仪器，以探测气相有机氧化化学和有机颗粒物（PM）演变之间的复杂相互作用。其中一种仪器是化学电离质谱仪（CIMS），设计用于灵活、高灵敏度地测量临界自由基（OH、HO 2和RO 2）、硫酸蒸汽或氨。自由基水平控制着大气中有机化合物氧化的速率和机制;氨和硫酸盐，沿着有机物，是新粒子形成和在大气中生长的关键因素。另一种仪器是高分辨率飞行时间气溶胶质谱仪（HR-AMS），质量分辨率为5000（_0.02 amu）。HR-AMS将测量50至700 nm之间的颗粒组成的尺寸依赖性非耐火部分，明确分辨颗粒中的C：H：O：N：S。HR-AMS配备了光散射模块来探测单个粒子，因此能够探测单个粒子，从而能够对来自不同来源的气溶胶的混合状态进行实验。这些仪器将共同推动大气化学前沿的研究。有机气溶胶是一个动态系统，结合了气相和颗粒相之间的相分配与氧化化学，这导致与大气颗粒相关的有机材料的挥发性分布在其在大气中大约一周的停留时间内不断演变。与此同时，凝聚相测量的最新技术正在迅速发展，因此现在可以测量有机质谱中观察到的大多数碎片的分子式。因此，HR-AMS将能够测量有机颗粒物的氧化态，因为它是由于气相氧化反应而演变的。