Investigating Fundamental Chemical and Physical Processes Affecting Gas-Particle Partitioning Using Levitated Droplet-Mass Spectrometry

使用悬浮液滴质谱法研究影响气体粒子分配的基本化学和物理过程

基本信息

批准号：
1808084
负责人：
Frank Keutsch
金额：
$ 58.5万
依托单位：
Harvard University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-01 至 2024-07-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1808084&HistoricalAwards=false
关键词：
Investigating Fundamental Chemical Physical Processes

项目摘要

This award is supported by the Environmental Chemical Sciences Program of the Division of Chemistry. Professor Frank Keutsch of Harvard University and his students investigate the fundamental processes involved in separating compounds between the air and the surface of particles (aerosols) in the atmosphere. This portioning between the air and the surfaces of solids that are present in the air is poorly understood however, one phase may be preferred over the other due to incomplete mixing, physical barriers, and/or chemical reactions on the aerosol particles. Laboratory studies are conducted on single aerosol particles to isolate and investigate how and why compounds stick to their surfaces. These experimental studies provide fundamental parameters for improving computer models on aerosol formation and changes in these particles with time (ageing). This research is important as it may ultimately improve regional and global models of aerosols, which are relevant to air quality and human and animal health. Professor Keutsch also designs laboratory experiments to introduce a systems approach to undergraduate education. This approach considers not only individual reactions but the coupled chemical and physical feedbacks that exist between different parts of the whole system (in this case, the gas and solid phases). His students learn about instrumentation design and reactions at and far from equilibrium. In addition, underrepresented high school students at Cambridge, MA high schools are mentored and work in the research laboratory learning to communicate their research to others in the field and gaining confidence in their abilities to participate in scientific fields. A new approach is used to study aerosol partitioning that combines levitation of individual micron-sized particles with mass-spectrometric (MS) detection. This technique allows the measurement of the molecular-level evolution of a droplet over atmospherically relevant time scales. Molecular-level detection is a novel approach that may advances trapped droplet methods. After further optimization of the trapped-droplet MS, specific research questions related to the role of non-ideal mixing, oligomer formation, transition metal complex photochemistry, and aerosol physical properties in gas-particle partitioning are addressed. This research is done in collaboration with chemists and atmospheric sciences. Results are compared with state-of-the-art models which improve the representation of the fundamental chemical and physical processes in the models, and hence, improve predictive capabilities.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.

该奖项得到化学部环境化学科学项目的支持。哈佛大学的弗兰克·科伊奇教授和他的学生研究了空气和大气中颗粒（气溶胶）表面之间的化合物分离所涉及的基本过程。人们对空气和空气中存在的固体表面之间的这种分配知之甚少，然而，由于不完全混合、物理屏障和/或气溶胶颗粒上的化学反应，一相可能优于另一相。对单个气溶胶颗粒进行实验室研究，以分离和研究化合物如何以及为何粘附在其表面。这些实验研究为改进气溶胶形成和这些颗粒随时间变化（老化）的计算机模型提供了基本参数。这项研究很重要，因为它可能最终改善与空气质量以及人类和动物健康相关的区域和全球气溶胶模型。科伊奇教授还设计了实验室实验，以将系统方法引入本科教育。这种方法不仅考虑单个反应，还考虑整个系统不同部分（在本例中为气相和固相）之间存在的耦合化学和物理反馈。他的学生学习仪器设计以及处于平衡状态和远离平衡状态时的反应。此外，马萨诸塞州剑桥市高中代表性不足的高中生接受指导并在研究实验室工作，学习如何与该领域的其他人交流他们的研究成果，并对自己参与科学领域的能力充满信心。一种新方法用于研究气溶胶分配，该方法将单个微米级颗粒的悬浮与质谱 (MS) 检测相结合。该技术允许测量液滴在大气相关时间尺度上的分子水平演化。分子水平检测是一种可能推进捕获液滴方法的新方法。进一步优化捕获液滴质谱仪后，解决了与非理想混合、低聚物形成、过渡金属络合物光化学和气溶胶物理性质在气体-颗粒分配中的作用相关的具体研究问题。这项研究是与化学家和大气科学合作完成的。将结果与最先进的模型进行比较，这改进了模型中基本化学和物理过程的表示，从而提高了预测能力。该奖项反映了 NSF 的法定使命，并被认为值得通过使用评估来支持基金会的智力价值和更广泛的影响审查标准。

项目成果

期刊论文数量（3）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Revisiting the reaction of dicarbonyls in aerosol proxy solutions containing ammonia: the case of butenedial

重新审视含氨气溶胶代理溶液中二羰基的反应：以丁烯二醛为例

DOI：
10.5194/acp-21-8809-20
发表时间：
2021
期刊：
Atmospheric chemistry and physics
影响因子：
6.3
作者：
Jack C. Hensley, Adam W.
通讯作者：
Jack C. Hensley, Adam W.

Single-particle experiments measuring humidity and inorganic salt effects on gas-particle partitioning of butenedial

单颗粒实验测量湿度和无机盐对丁烯二醛气体-颗粒分配的影响

DOI：
10.5194/acp-19-14195-2019
发表时间：
2019
期刊：
Atmospheric Chemistry and Physics
影响因子：
6.3
作者：
Birdsall, Adam W.;Hensley, Jack C.;Kotowitz, Paige S.;Huisman, Andrew J.;Keutsch, Frank N.
通讯作者：
Keutsch, Frank N.