【作者】 王军国；

【导师】 刘福生；

【作者基本信息】 西南交通大学 ， 凝聚态物理， 2012， 硕士

【摘要】 水作为自然界普遍存在的物质之一,备受人们的关注。因为水广泛的参与到自然界中的物理,化学,生物等作用。尽管人们从很早开始就已经研究水的相关性质,但是到目前为止,水的许多相关领域仍然不被人类所了解。比如水的结冰问题。近年来,利用光谱技术探索常态下界面处水的结构变化发展为一个新的研究方向。这项研究有利于揭示自然界中有水参与的界面作用的机理问题。但是,冲击压缩状态下界面水的结构变化研究依然很少,这是由于在冲击波物理试验中获得物质真实结构信息的困难较大。要求实验的诊断技术必须具有灵敏度高,同步性好的特征。本文采用光透射技术研究了石英/水界面处水的冲击结构相变,并且获得了以下几方面结论：(1)石英材料能够作为实验中的透明窗口。本文研究了弹丸速度为350m/s时石英材料的冲击压缩状态,发现石英材料在冲击压缩状态下依然保持良好的透明性,并且在压力卸载过程中,石英材料的透明性没有发生变化。(2)界面处水的结构相变与石英界面的特性相关。探索了不同酸碱环境中水/石英界面处水的冲击结构相变,证实界面处样品水的冲击结构相变与石英界面的电场诱导效应密切相关,且受石英界面特性影响较大。(3)实验发现了水的冲击结构相变的完整过程。探索了单次冲击条件下界面水的冲击结构相变,发现相变过程明显分为四个阶段,与理论研究的结果一致。(4)实验证实了界面水冲击结构相变是高密度水被诱导的结果。实验发现在强酸环境下石英界面表现为中性,但界面水仍然能够发生冲击结构相变,证实水被冲击进入高密度水状态,处于亚稳定性的高密度水被诱导相变。更多还原

【Abstract】 Water is always caused much attention of scientists because it is one of substances common in nature. And water plays a important role in a wide range of physical, chemical, biological in nature. Although people has been studied water over the past decades, but so far, many related knowledge of the water has not been master by human. Such as the solidification of water. In recent years, the exploring the structure of water under normal conditions at the interface is a new research. The study helps to reveal the mechanism of water participation in the interface action. But there are small people to study the structure changes of water in the interface, which is due to quite difficult to obtain true information in the shock experiment. So the experimental equipment with high sensitivity diagnostic and highly accurate synchronization techniques are needed. In this thesis, we studied the water freezing under shock compression with a novel technique using light transmission measurements and obtained the following conclusions:(1) Fused quartz can be used as a transparent window in the experiments. We study the fused quartz state under shock compression, in which the velocity of projectile is350meters per second. Fused quartz remains is transparent in the state of shock compression, and it is confirmed in the uninstall process.(2) The phase transition is dependent on the characteristics of quartz in the interface. Water’s structure phase transition is explored in various pH environments in water/quartz interface under shock compression. We demonstrate that phase transition is closely related to the electric field of the quartz interface which induced the solidification of water.(3) It found the complete process of water’s phase transition. The phase transition process was divided into four stages in the interface under single shock compression which is consistent with the theoretical results.(4) The experiments confirmed that high-density water was induced into ice under shock compression. At very low pH, the quartz surface is nearly neutral, but water in the interface can still occur to the phase transition. Because high-density water is a metastable liquid in which phase transition occurs more easily.更多还原