半挥发性有机物 (SVOC) 对二次有机气溶胶 (SOA) 的形成有重要作用，但SVOC经化学转化生成SOA的过程尚难以准确定量。本项目针对SVOC的组分、来源及物理化学转化：1.构建典型源排放SVOC的成分数据库，开展基于外场观测的源排放验证；2.以中间态SVOC为核心，在气态、颗粒态有机物全组分同步测量基础上，探索SVOC的演化过程，建立SVOC-SOA的参数化关系；3.增补SVOC气相化学机制，构建并耦合SVOC-SOA生成模块，以实测中间态SVOC为约束，改进和优化区域空气质量模型，实现SVOC从源排放到SOA生成的全程模拟；4.利用优化的区域空气质量模型，揭示SOA对SVOC的响应关系，判别影响SOA生成的关键因子。通过上述研究，开展SVOC源排放-中间物种-化学转化-影响因子的系统研究，提升我国SOA模式模拟能力，为阐释我国东部地区SOA形成机制，制定相关控制策略提供技术支撑。

Semi-volatile organic compound (SVOC) is of great importance for the formation of secondary organic aerosol (SOA). However, the knowledge on the contribution of SVOC to the formation of SOA via chemical conversion and gas-particle partition is still limited. The project will be aimed at the abundance, sources of SVOC and the physical and chemical behaviors of SVOC to the formation of SOA; 1. Establish the data base for the speciated SVOCs from typical anthropogenic sources based on the source-oriented and field measurements; 2. By considering the intermediate SVOC as the link between primary precursors and SOA, explore the physical/chemical evolution of SVOC and parameterize the relationship between SVOC and SOA; 3. Based on the above investigation, supplement the mechanisms for the evolution of SVOC, develop the SVOC-SOA modules and couple them into the regional air quality model (WRF-Chem), improve and optimize the WRF-Chem model by using the intermediate SVOC as constrain to conduct process analysis from SVOC emissions to the formation of SOA; 4. Using the improved regional air quality model to explore the roles of SVOC in the formation of SOA and the key impact factors. Through the above investigation, this study will perform a systematic analysis on the “source emissions-intermediate compounds-chemical conversion-impact factors”, aiming to evaluate the contribution of SVOC to the formation of SOA, which could help to improve the model performance of the simulation of SOA, elucidate the detailed mechanisms of the formation of SOA in East China, and provide technique support for the implementation and formulation of control measures on SVOC, SOA and fine particles (PM2.5).