大气有机胺时空分布及其在新颗粒生成事件中的作用机制

像氨气一样，有机胺能够与大气酸性物质反应形成稳定的分子簇。然而，有机胺在新颗粒生成和增长中的贡献和作用机制尚不确定。本项目拟以离子在线观测和膜采样离线分析为主、结合实验室模拟论证的方法研究长三角大气有机胺的时空分布及其在新颗粒生成中的作用机制。通过长期采样和深入分析，系统表征大气颗粒物有机胺的粒径分布、时空变化，明确影响有机胺浓度和粒径分布的关键因素，并结合正矩阵因子分解法解析有机胺的来源。组织在线和离线相结合、气体和颗粒物相结合为特点的强化观测，考察新颗粒生成事件中气、固两相有机胺的浓度、分配机制，重点研究有机胺浓度和颗粒物酸性等对新颗粒生成和增长速率的影响，揭示有机胺在新颗粒生成和增长过程的作用机制。以外场观测资料为基础，利用实验室模拟明确有机胺和氨气在新颗粒生成事件中是否存在协同效应。所得结果有助于揭示长三角新颗粒生成事件频发的内在机制。

Like ammonia, amines can react with atmospheric acids resulting in the formation of stable clusters. However, the role of amines in the initiation of new partcle formation events (NPF) and growth of nucleating aerosols remain uncertain. In this proposal, temporal and spatial variation of particulate amines (aminium) and their role in NPF are investigated through online monitoring and offline analysis of cascade samplers coupled with laboratory studies. Temporal variation and size distribution of particulate amines are characterized with extended field observations. We try to explore the key factors determing particluate amines and source origin of amines by PMF source apportionment. Intensive campaigns including online monitoring and offline determination of gas and particle phase amines and other pollutants will be deployed for several times to reveal gas-to-particle conversion mechanism in NPF. Effect of amine concentration and particulate acidity on NPF is stressed. Synergistic effect between amines and ammonia during NPF will be revealed by simualtion in laboratory based on the atmospheric concentrations of key components. our work will be helpful to provide new insights onto the mechanism of frequent NPF in the Yangtze River Delta.