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

• 来源期刊: 科学通报(英文版)
• 学科: 地球科学
• 年，卷（期）: 2012,（6）
• 页码范围: 591-594
• 页数: 4页
• 分类号: X513
• 语种: 中文

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.