Laboratory Studies of Multicomponent Aerosol Nucleation Involving Organic Amine Compounds

将在对流层低层条件下进行涉及有机胺化合物的多组分气溶胶成核的实验室研究，以研究（1）胺对硫酸气溶胶成核的影响，（2）与单独的氨或胺相比，氨和胺一起如何增强硫酸成核，（3）在有机酸存在下胺对硫酸气溶胶成核的影响（例如，乙酸或草酸），（4）有机酸和氨/胺是否可以在没有硫酸的情况下产生新的颗粒，以及（5）胺如何在分子簇的初始形成及其随后的气溶胶颗粒的生长中发挥不同的作用。这些实验室产生的气溶胶的组成将与各种大气环境中的环境气溶胶进行比较，以了解有机化合物在气溶胶成核过程中所起的作用。气候变化是当今最重要的科学和社会经济问题之一。气溶胶-云-气候的相互作用还不足以对未来气候做出可靠的预测。成核是新粒子的主要来源，因此是控制气溶胶浓度、云凝结核（CCN）数量和最终云丰度的重要过程。新的粒子也可能通过改变云的性质，如云的寿命和降水效率，对气候产生显着的间接影响。事实上，气溶胶是气候建模中最大的不确定性来源，因此了解控制气溶胶形成的成核和生长过程是大气研究的一个高度优先事项。该项目的结果将有助于减少当前气溶胶成核理论的不确定性以及区域和全球气溶胶模式中CCN浓度预测的不确定性。通过参与该项目，一名博士后研究员，一名博士生和几名本科生将获得大气化学，气溶胶技术和气候科学方面的宝贵知识和经验。

Laboratory studies of multi-component aerosol nucleation involving organic amine compounds under conditions relevant to the lower troposphere will be carried out to investigate (1) the effects of amines on sulfuric acid aerosol nucleation, (2) how ammonia and amines together enhance sulfuric acid nucleation compared to ammonia or amines alone, (3) the effects of amines on sulfuric acid aerosol nucleation in the presence of organic acids (e.g., acetic or oxalic acids), (4) whether organic acids and ammonia/amines can produce new particles without sulfuric acid, and (5) how amines play different roles in the initial formation of molecular clusters and their subsequent growth to aerosol particles. The composition of these laboratory-generated aerosols will be compared with that of ambient aerosols in various atmospheric environments to understand the roles that organic compounds play in the aerosol nucleation processes.Climate change is one of the most important scientific and socioeconomic issues of the day. Aerosol-cloud-climate interactions are not well enough understood to make reliable predictions about future climate. Nucleation is a predominant source of new particles and thus is an important process that controls aerosol concentrations, cloud condensation nucleus (CCN) populations and, ultimately, cloud abundance. New particles may also have significant indirect effects on climate through their modification of cloud properties such as albedo, lifetime, and precipitation efficiency. Indeed, aerosols represent the greatest source of uncertainty in climate modeling, and thus understanding the nucleation and growth processes that govern aerosol formation are a high priority in atmospheric research. The results of this project will help to reduce the uncertainties in the current aerosol nucleation theories and the uncertainties in the predictions of CCN concentrations in regional and global aerosol models. Through involvement in this project a postdoctoral fellow, a PhD student, and several undergraduate students will gain valuable knowledge and experience in atmospheric chemistry, aerosol technology, and climate science.