人工冰核的核化速率实验

Experimental Study on Nucleation Rate of Artificial Ice Nuclei

如同成冰总数一样,核化速率也是催化剂性能的关键参数之一,对于科学设计和指导人工影响天气试验和作业有非常重要的意义,以前很少引起人们的关注。通过借鉴DeMott等使用的化学动力学方法,利用催化剂检测实验中时间特征等资料展开核化速率研究。结果表明,对于其他实验条件相同时,不同样品核化速率不同;同一样品不同温度动态特征明显不同:对于低温段(<-16℃),形成冰晶对应快过程,主要表现是凝结冻结核化、凝华核化;而较高温度(≥-12℃)时形成冰晶是慢过程(接触核化、浸入核化机制)起主要作用。建议人工影响天气外场试验和作业中选择催化剂应关注其核化速率差异,根据实验目的优选具有不同核化速率的催化剂。

As nucleation effectiveness,the nucleation rate of artificial ice nuclei（AIN） also is one of the most important properties of seeding agents in weather modification.But it was rarely paid attention in the bypast field experiments and operations.The chemical kinetic approach is employed in this study.The results show that the nucleating rate,efficiency and even the nucleating mechanism of these pyrotechnics are different.For different aims of weather modification operating and different type clouds,we shall choose different seeding agents with different nucleating rates.