New Particle Formation Experiments: Nucleation and Growth

新的粒子形成实验：成核和生长

• 批准号: 1761638
• 负责人: David Hanson
• 金额: $ 38.41万
• 依托单位: Augsburg 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: 2018-06-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1761638&HistoricalAwards=false
• 关键词: New; Particle; Formation; Experiments; Nucleation

This project focuses on the formation and growth of new particles in the atmosphere. Laboratory experiments will be conducted to measure changes in the rate of new particle formation and growth with changes in composition, temperature, and relative humidity. The results are expected to lead to improved accuracy in predicting the impacts of new particle formation on climate, health and visibility.Laboratory research includes experiments to: (1) conduct measurements of nucleation rates in the ammonia - H2SO4 system as a function of reagent concentrations and temperature; (2) conduct measurements of the synergistic effect of ammonia on nucleation rates for the amine - H2SO4 system at low H2SO4 concentrations; (3) characterize growth rates using a Photolytic Flow Reactor with growth via H2SO4 and using a second flow reactor with growth agents injected in the vapor phase; (4) measure the nanoparticle size-dependency of the growth capabilities of select organic compounds; (5) estimate absolute growth rates (i.e., uptake efficiency) by incorporating measured gas-phase concentrations into model simulations; and (6) explore the capability of the Photolytic Flow Reactor as a tool for understanding growth via uptake of complex secondary oxidation products such as are produced in photo-oxidation of alpha-pinene.The Principal Investigator (PI) plans to use computational fluid dynamics (CFD) simulations of the flow reactor to bolster the interpretation of the experimental results. The CFD simulations allow for estimates of the free energies of small molecular clusters and extrapolations of the results to conditions in other experiments so that nucleation rates can be compared. The PI intends to compare the results from this project with global atmospheric particle formation measurements from the CERN CLOUD project.The project will help develop undergraduate research capabilities by exposing undergraduates to high-level experimental and computational work that will prepare them for careers in science.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.

该项目的重点是大气中新粒子的形成和生长。 将进行实验室实验，以测量随着成分、温度和相对湿度的变化，新颗粒形成和生长速率的变化。 实验室研究包括：（1）测量氨-硫酸体系中的成核速率随反应物浓度和温度的变化;（2）在低H_2SO_4浓度下，测量氨对胺-H_2SO_4体系成核速率的协同效应;（3）使用通过H2SO 4生长的光解流动反应器和使用在气相中注入生长剂的第二流动反应器表征生长速率;（4）测量所选有机化合物的生长能力的纳米颗粒尺寸依赖性;（5）估计绝对增长率（即，吸收效率），将测量的气相浓度纳入模型模拟;及（6）探索光解流动反应器作为理解通过吸收复杂的二次氧化产物（例如在α-蒎烯的光氧化中产生的产物）的生长的工具的能力。首席研究员（PI）计划使用计算流体动力学（CFD）流动反应器的模拟，以支持实验结果的解释。 计算流体力学模拟允许小分子团簇的自由能的估计和外推的结果在其他实验中的条件，使成核率可以比较。 PI打算将该项目的结果与CERN CLOUD项目的全球大气颗粒物形成测量结果进行比较。该项目将通过让本科生接触高浓度的该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准。

项目成果

Measurement report: Sulfuric acid nucleation and experimental conditions in a photolytic flow reactor

测量报告：光解流反应器中的硫酸成核和实验条件

• DOI: 10.5194/acp-21-1987-2021
• 发表时间: 2021
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Hanson, David R.;Menheer, Seakh;Wentzel, Michael;Kunz, Joan
• 通讯作者: Kunz, Joan

H 2 SO 4 and particle production in a photolytic flow reactor: chemical modeling, cluster thermodynamics and contamination issues

H 2 SO 4 和光解流反应器中的颗粒产生：化学建模、团簇热力学和污染问题

• DOI: 10.5194/acp-19-8999-2019
• 发表时间: 2019
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Hanson, David R.;Abdullahi, Hussein;Menheer, Seakh;Vences, Joaquin;Alves, Michael R.;Kunz, Joan
• 通讯作者: Kunz, Joan

Effects of Precursor Structure on First-Generation Photo-Oxidation Organic Aerosol Formation

• DOI: 10.3389/fenvs.2022.892389
• 发表时间: 2022-06
• 作者: D. Sofio;D. Long;T. Kohls;J. Kunz;M. Wentzel;D. Hanson

Semiempirical H 2 SO 4 –H 2 O Cluster Standard Gibbs Reaction Energies from Nucleation Experiments: Improved Temperature Dependence

成核实验中的半经验 H 2 SO 4 →H 2 O 簇标准吉布斯反应能量：改进的温度依赖性

• DOI: 10.1021/acs.jpca.2c04737
• 发表时间: 2022
• 期刊: The Journal of Physical Chemistry A
• 作者: Hanson, David R.;Case, Amanda S.
• 通讯作者: Case, Amanda S.

Particle Formation from Photooxidation of αpinene, Limonene, and Myrcene

α蒎烯、柠檬烯和月桂烯的光氧化形成颗粒

• DOI: 10.1021/acs.jpca.1c08427
• 发表时间: 2022
• 期刊: The Journal of Physical Chemistry A
• 作者: Hanson, David R.;Sawyer, Adam;Long, Darlene;Sofio, Dominick;Kunz, Joan;Wentzel, Michael
• 通讯作者: Wentzel, Michael