CDI-Type I: Collaborative Research: Development of computational algorithms and analysis tools for molecular-level understanding of complex atmospheric nucleation processes

新形成的大气气溶胶粒子通过影响地球的辐射平衡，对全球气候产生相当大的影响。成核在这些粒子的形成中起着关键作用。了解多组分气体混合物中粒子如何成核不仅对气候和天气有重要意义，而且对气体分离、污染控制和纳米技术等广泛的技术应用也有重要意义。大气成核涉及多尺度过程，从质子转移到分子凝聚和蒸发事件，最终形成罕见的临界核。该项目的目标是：(i)开发计算算法和分析工具，用于有效研究多组分气体到颗粒的成核过程；（ii）阐明与大气相关的成核过程，并通过战略性选择的实验室实验，在亚3nm尺度上测量簇大小和质量分布，验证速率预测。（iii）部署一个免费的网络工具，通过提供一个总体框架来可视化和分析任何类型的气体到颗粒成核过程的基于粒子的模拟所产生的大量数字数据，从而使大规模建模者和实验研究人员能够收集预测的大气成核率并了解机制，从而将数据转化为知识，并作为成核教学的辅助工具。该项目影响了我们对大气成核途径的理解，并揭示了成核动力学的定量建模如何影响全球气候模型和影响大气成核的能力。在来自不同领域、不同学术机构和国际合作者的研究人员的合作推动下，本科生和研究生的教育、培训和指导以一种独特的方式推进，扩大了参与范围。从这个项目中获得的知识在团队成员教授的课程和实验室中注入了发现的兴奋。向初中和科学博物馆开展的外展活动使更广泛的社区了解大气成核。这是一个基于网络的发现和创新项目奖，由化学部、土木、机械和制造创新部、国际科学和工程办公室以及刺激竞争性研究的实验项目共同资助。

Newly formed atmospheric aerosol particles exert a considerable impact on global climate by affecting the Earth's radiation balance. Nucleation plays a pivotal role in the formation of these particles. Understanding how particles nucleate in a multi-component gas mixture has important implications not only for climate and weather but also wide-ranging technological applications including gas separations, pollution control, and nanotechnology. Atmospheric nucleation involves multi-scale processes ranging from proton transfer to molecular condensation and evaporation events and culminating in the rare formation of the critical nucleus. The goals of this project are (i) to develop computational algorithms and analysis tools for efficient investigations of multi-component gas-to-particle nucleation processes, (ii) to elucidate atmospherically relevant nucleation processes and to validate the rate predictions through strategically selected laboratory experiments measuring cluster size and mass distributions at the sub-3 nm scale, and (iii) to deploy a freely-available cyber-tool that transforms data to knowledge by enabling large-scale modelers and experimental researchers to harvest predicted atmospheric nucleation rates and learn about mechanisms, by providing a general framework to visualize and analyze the abundance of digital data generated by particle-based simulations for any type of gas-to-particles nucleation process, and by being an aid for teaching about nucleation.The project impacts our understanding of atmospheric nucleation pathways and sheds light on how quantitative modeling of the nucleation kinetics affects global climate models and impacts the ability to influence atmospheric nucleation. Driven by the partnership of researchers from different fields, diverse academic institutions, and international collaborators, the education, training, and mentoring of undergraduate and graduate students is advanced in a unique way that broadens participation. Knowledge gained from this project infuses the excitement of discovery in courses and laboratories taught by the team members. Outreach activities to junior high schools and science museums allow a broader community to learn about atmospheric nucleation.This is a Cyber-Enabled Discovery and Innovation Program award and is co-funded by the Division of Chemistry, the Division of Civil, Mechanical & Manufacturing Innovation, the Office of International Science & Engineering, and the Experimental Program to Stimulate Competitive Research.