【摘要】 用步冷曲线法研究室温冷却环境下成核剂-Na2HPO4·12H2O复合体系的过冷性能,分析成核剂的添加量和晶体结构对过冷度的影响.结果表明:Na2SiO3·9H2O、NaF、CH3COONa·3H2O和Na2B4O7·10H2O这4种成核剂对Na2HPO4·12H2O的过冷现象有不同程度的改善.为有效改善过冷,成核剂的添加量有一个合适的范围.在10g的Na2HPO4·12H2O中,分别添加0.30g的Na2SiO3·9H2O、0.15g的CH3COONa·3H2O、0.05g的NaF和0.05g的Na2B4O7·10H2O时,抑制过冷的效果最好.同时发现,与Na2HPO4·12H2O晶体结构不同的成核剂Na2SiO3·9H2O改善过冷的效果最显著;与Na2HPO4·12H2O晶体结构相同的成核剂中,Na2B4O7·10H2O改善过冷的效果优于CH3COONa·3H2O.更多还原

【Abstract】 The supercooling performances of nucleating agent-Na2HPO4 ·12H2O composite system in room temperature environment was researched with step cooling method.The effect of nucleating agent addition amount and crystal structure on the supercooling degree was analyzed.The experimental results showed that four kinds of nucleating agents such as Na2SiO3 ·9H2O,NaF,CH3COONa·3H2O,and Na2B4O7·10H2O would improve the supercooling phenomenon of Na2HPO4·12H2O to some extent.In order to improve the supercooling effectively,there is an appropriate range of nucleating agent addition amount.When adding 0.30 g of Na2SiO3·9H2O,0.15 g of CH3COONa·3H2O,0.05 g of NaF,and 0.05 g of Na2B4O7·10H2O respectively into 10 g of Na2HPO4·12H2O,the inhibiting effect of supercooling would be the best.Meantime,it was discovered that the nucleating agent Na2SiO3·9H2O with distinct crystal structure from the Na2HPO4·12H2O would have the most remarkable effect of improvement on the supercooling inhibition.The crystal structures of nucleating agents Na2B4O7·10H2O and CH3COONa·3H2O were identical to that of Na2HPO4·12H2O,but Na2B4O7·10H2O would be better for improving the supercooling than CH3COONa·3H2O.更多还原