Abstract
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.
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Qian, Z., Wang, F., Zheng, Y. et al. Crystallization kinetics of sea-salt aerosols studied by high-speed photography. Chin. Sci. Bull. 57, 591–594 (2012). https://doi.org/10.1007/s11434-011-4907-z
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DOI: https://doi.org/10.1007/s11434-011-4907-z