Crystallization kinetics of sea-salt aerosols studied by high-speed photography  

作　　者：QIAN ZhengGang WANG Feng ZHENG YuXia YU JunYing ZHANG YunHong 

机构地区：[1]Institute of Chemical Physics,Beijing Institute of Technology,Beijing 100081,China

出　　处：《Chinese Science Bulletin》2012年第6期591-594,共4页

基　　金：supported by the National Natural Science Foundation of China (20933001,41175119 and 20873006);the National Basic Research Program of China (2009CB220100);the Trans-Century Training Program Foundation for the Talents

摘　　要：Morphological changes with decreasing relative humidity(RH) of supersaturated sea-salt aerosol droplets on a quartz substrate were observed using a high-speed video-camera.Stable gypsum(CaSO4·2H2O) or the metastable hemihydrate(CaSO4·0.5H2O) were precipitated as the RH decreased.The dynamic process of crystal growth under steady-state humidity was studied by controlling the RH;the metastable hemihydrate was precipitated at 70.5%-77.1% RH,and the apparent crystal growth rate was between 1.42 and 2.33 μm3/s.Stable gypsum was formed at 80.7%-82.2% RH,and the apparent crystal growth rate was between 0.70 and 0.81 μm3/s.Morphological changes with decreasing relative humidity （RH） of supersaturated sea-salt aerosol droplets on a quartz substrate were observed using a high-speed video-camera. Stable gypsum （CaSO4· 2H2O） or the metastable hemihydrate （CaSO4· 0.5H2O） were precipitated as the RH decreased. The dynamic process of crystal growth under steady-state humidity was studied by controlling the RH; the metastable hemihydrate was precipitated at 70.5%-77.1% RH, and the apparent crystal growth rate was between 1.42 and 2.33 μm3/s. Stable gypsum was formed at 80.7%-82.2% RH, and the apparent crystal growth rate was between 0.70 and 0.81 μm3/s.

关 键 词：气溶胶 结晶动力学 高速摄影 海盐 晶体生长速率 相对湿度 稳定状态 形态学变化 

分 类 号：TQ026.5[化学工程] X513[环境科学与工程—环境工程]