Developing the Molecular Underpinnings for Mechanisms of Growth of Secondary Organic Aerosol (SOA) Particles in Air

本项目研究导致大气中二次有机气溶胶（SOA）形成和增长的过程。这些非常小的颗粒是由植物排放的气态生物碳氢化合物氧化形成的。这项研究的结果将为在大气模型中参数化SOA过程提供指导。该项目的具体目标是：(1)量化在一系列实验条件下，将具有不同性质（如官能团和蒸气压）的示踪剂纳入由各种气相前体形成的SOA中；(2)测量来自不同SOA的各种示踪剂的解吸率，并将其输入拟议的分子模型；(3)利用萃取电喷雾质谱法阐明SOA粒子表面区域的性质；(4)测定不同结构的胺对固体二酸和SOA的吸收系数的大小、时间依赖性和机理。

This project addresses the processes that lead to the formation and growth of secondary organic aerosol (SOA) in the atmosphere. These very small particles are formed from the oxidation of gaseous biogenic hydrocarbons, emitted by plants. The results of this research will provide guidance for parameterizing SOA processes in atmospheric models.The specific objectives of the project are to: (1) quantify incorporation of tracers with different properties such as functional groups and vapor pressures into SOA formed from various gas phase precursors under a range of experimental conditions; (2) measure rates of desorption of various tracers from different SOA for input into a proposed molecular model; (3) elucidate the nature of the surface region of SOA particles using extractive electrospray ionization mass spectrometry; and (4) measure the magnitude, time dependence and mechanism of uptake coefficients for amines of different structures on solid diacids and SOA.