氯化钾水溶液中介稳区的研究

在一套恒速冷却装置上测定了氯化钾水溶液介稳区宽度.加晶种与不加晶种的两条直线不平行,加晶种直线的斜率小于不加晶种直线的斜率.实验表明:介稳区宽度不仅取决于冷却速率,而且与停留时间有关.通过三组不同条件的实验数据,得出介稳区宽度、冷却速率和停留时间三者关系的经验模型.并测定了介稳区测定器的搅拌速度,初步考察了搅拌速度对介稳区测定结果的影响.

A Study on the Metastable Zone in Solution of Potassium Chloride

The widths of metastable zone for aqueous solution of potassium chloride were determined in a constant cooling rate set. Under the seeded and unseeded conditions, two unparallel log b-log △θmax lines were obtained. The slope of the line of seeded was less than that of the unseeded. The width of metastable zone is dependent not only on the rate of cooling, but also on the retention time.Based on three groups of experimental data of different conditions, an empirical correlation of metastable zone width (△θmax), cooling rate( b ), and retention time(τ) has been found:b = 0.443 △θmax3.167(τ+1)0.904The rate of agitation of the apparatus was determined by Laser Doppler Velocimeter (LDV). A prelimenary study of the effect of the rate of agitation on metastable zone was made.