Noval Experimental Techniques for the physical and chemical characterization of Nucleation mode Aerosol Particles

气溶胶颗粒对地球辐射收支、大气复杂的多相化学、营养物或污染物的生态系统通量以及空气质量的影响在很大程度上取决于颗粒的数量、大小、化学成分及其在大气中的分布。因此，需要对气溶胶粒子的相关源、汇、输送机制和转化过程进行识别和量化，以提高我们对大气气溶胶的基本认识，并制定适当的模式参数化。本研究旨在探索创新的实验技术，以直接量化大气低层边界层中成核模式气溶胶颗粒（直径小于30 nm）的湍流通量和化学成分。建议研制成核模式气溶胶粒子的小型化收集系统，并将其与现场便携式离子阱飞行时间质谱仪耦合，用于气溶胶化学成分的原位分析。质谱仪和真涡旋积累的结合将产生独特的气溶胶通量测量能力。这些新实验技术的现场部署将有助于改进气溶胶传输机制和新形成颗粒的大气分布的描述，以及更好地理解气体到颗粒的转化过程，特别是有机物种在二次颗粒形成中的相关性。因此，本提案将解决基本的科学问题，例如气溶胶颗粒对全球气候的影响，以及重要的社会问题，例如关于气溶胶健康影响的有效控制战略和监管政策的设计和实施。

The impact of aerosol particles on the Earth’s radiation budget, the complex multiphase chemistry of the atmosphere, ecosystem fluxes of nutrients or pollutants, and air quality is strongly dependent on particle number, size, chemical composition and their distribution within the atmosphere. Therefore, the relevant sources, sinks, transport mechanisms and transformation processes of aerosol particles need to be identified and quantified in order to improve our fundamental understanding of the atmospheric aerosol and to formulate adequate model parameterizations. This proposal aims at exploring innovative experimental techniques for the direct quantification of turbulent fluxes and the chemical composition of nucleation mode aerosol particles (less than 30 nm in diameter) in the lower atmospheric boundary layer. It is suggested to develop a miniaturized collection system for nucleation mode aerosol particles, and couple it to a field-portable ion trap time-of-flight mass spectrometer for in-situ analysis of the aerosol chemical composition. The combination of the mass spectrometer and true eddy accumulation will yield unique aerosol flux measurement capabilities. Field deployment of these novel experimental techniques will contribute to an improved description of aerosol transport mechanisms and the atmospheric distribution of newly formed particles as well as a better understanding of gas-to-particle conversion processes, especially the relevance of organic species in secondary particle formation. Thus, this proposal will address fundamental scientific questions, e.g. the impact of aerosol particles on global climate, and important societal issues such as the design and implementation of effective control strategies and regulatory policies with regard to aerosol health effects.