Interfacial Melting and Frost Heave in Ice

这个项目是一个为期三年的实验研究，在低于纯水冰点的温度下，存在于冰晶边界的液态水的动力学。这一过程被称为预融化，在海冰中盐水的重新分配、污染物通过冰川的明显迁移、土壤和岩石的冻胀和风化速率等方面具有重要影响。预熔对几乎所有类型的材料都是常见的，但对冰的研究最为广泛。它可能是由吸附力、润湿、尺寸效应或衬底紊乱引起的，涉及表面物理和相变现象的许多方面。实验和理论项目将包括冰晶生长和晶体之间的不冻水运输作为温度和温差的函数的研究，以及冰晶和各种基质之间的研究。一个重要的目标将是开发在自然条件下冰生长和杂质输送的有用模型，以评估晶粒界面如何作为化学管道。＊＊＊

9523513 Wettlaufer This project is a three-year experimental study of the dynamics of liquid water existing at the boundaries of ice crystal at temperatures below the freezing point of pure water. This process, called premelting, has significant consequences in the redistributing of brine in sea ice, the apparent migrating of contaminants through glacier ice, and the rate of frost heave and weathering in soils and rocks. Premelting is common to virtually all types of materials, but has been most extensively studied in ice. It may be caused by adsorption forces, wetting, size effects, or substrate disorder, and involves many aspects of surface physics and phase transition phenomena. The experimental and theoretical program will include studies of ice crystal growth and unfrozen water transport between crystals as functions of temperature and temperature differences, as well as such studies between ice crystals and various substrates. An important objective will be the development of useful models for ice growth and impurity transport under natural conditions in order to assess how grain interfaces may serve as chemical conduits. ***