硬球体液体中的长距离应力相关性
Niklas Grimm1, Martin von Bischopinck2, Andreas Zumbusch2
1Fachbereich Physik, Universität Konstanz, 78457 Konstanz, Germany.
The Journal of chemical physics
|October 14, 2024
概括
剪切弹性出现在形成玻璃的液体中,显示出类似于固体的功率定律应力相关性. 这些相关性揭示了与声音传播一起增长的空间结构,为液态玻璃过渡提供了洞察力.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 统计力学就是统计力学.
背景情况:
- 液体到玻璃的转变是由剪切弹性的出现所表现的.
- 在固体中,包含周围的应力遵循埃舍尔比功率定律 (r-D).
- 了解液体中的应力动态对于解释玻璃状行为至关重要.
研究的目的:
- 调查玻璃成型液体中埃舍尔比式功率定律应力相关的出现.
- 在液态玻璃过渡过程中分析应力场的空间和时间行为.
- 为了将应力松机制与切削模量和摩擦等材料特性联系起来.
主要方法:
- 形成玻璃的硬球体流体的分子动力学模拟.
- 详细的张量分析压力相关性.
- 检查波动的力场和剪切应力动态.
主要成果:
- 在同位素液态的应力相关性中观察到未选的功率定律埃舍尔比模式 (r-D).
- 证明波动的力场放松到零,而剪切应力相关性形成功率定律结构.
- 确定了这些结构与声音传播一起生长的空间区域,表现出 r-D 和 r-D-2 指数.
- 显示在布朗系统中,剪切应力在这些区域内扩散放松.
结论:
- 形成玻璃的液体在完全固化之前表现出类似固体的应力相关性模式.
- 这些模式的出现与声音传播动态有关.
- 剪切应力的扩散放松是由布朗系统中的剪切模量和摩擦控制的.
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