Gas-to-Particle Conversion in Atmospheric Organic Systems

宋飞9307603气体到粒子的转化是大气中普遍存在的一个过程，了解其详细的化学和物理过程将使人们能够预测初级气体和颗粒排放对空气中颗粒物组成和大小的影响。这一综合研究计划确定了一些重要的人为和生物来源碳氢化合物在大气中形成二次有机气溶胶的机制。将在1000升的室内反应器中进行实验，以探索气相光氧化的机理。一个4立方米的室外雾霾小室将被用来产生有机气溶胶，用于通过气相色谱/质谱仪进行分子形态分析，而60立方米的室外雾霾小室将被用来研究气相和气到颗粒的综合转化动力学。各次级有机气溶胶成分和碳氢化合物光氧化产生的气溶胶的蒸汽压将用串联差分迁移率分析仪(TDMA)测定。来自个别实验研究的信息将被整合到数据分析阶段。将根据TDMA研究得出的浓度动力学、分子形态和物理性质，建立气相光氧化机理和气溶胶物理模型。

Seinfeld 9307603 Gas-to-particle conversion is a ubiquitous process in the atmosphere, understanding the detailed chemistry and physics of which will allow one to predict the effects of primary gaseous and particulate emissions on airborne particulate matter composition and size. This comprehensive research program determine the mechanisms of secondary organic aerosols formation in the atmosphere for a number of important anthropogenic and biogenic hydrocarbons. Experiments in a 1000 liter indoor reactor will be used to probe gas-phase photooxidation mechanisms. A 4 m3 outdoor smog chamber will be used to generate organic aerosols for molecular speciation analysis by gas chromatography/mass spectrometry, while the 60 m3 outdoor smog chamber will be employed to study the integrated gas-phased and gas-to-particle conversion dynamics. Vapor pressures of individual secondary organic aerosol constituents and of the aerosol generated by hydrocarbon photooxidation will be determined with the tandem differential mobility analyzer (TDMA). Information from the individual experiments studies will be integrated in the data analysis phase. Gas-phase photooxidation mechanisms will be formulated and aerosol physics models will be developed based on the concentration dynamics, molecular speciation, and the physical properties deduced from the TDMA studies.