通过局部弹性连接超冷液体的剪切稀释和动态异质性
Ke-Qi Zeng1, Dong-Xu Yu1, Zhe Wang1
1Department of Engineering Physics and Key Laboratory of Particle and Radiation Imaging (Tsinghua University) of Ministry of Education, Tsinghua University, Beijing 100084, China.
The Journal of chemical physics
|August 29, 2025
概括
超冷的液体表现出复杂的动态. 过渡弹性集群弥合了微观动态异质性和宏观剪切稀释,揭示了液体行为的新缩放规律.
科学领域:
- 凝聚物质物理
- 材料科学
- 病理学
背景情况:
- 超冷液体表现出复杂的动态,包括空间动态异质性和宏观剪切稀释.
- 这两种现象之间的关系一直是软物质物理学中的一个长期难题.
研究的目的:
- 阐明超冷液体中的动态异质性与剪切稀释之间的联系.
- 确定微观和宏观动力学的潜在物理机制.
主要方法:
- 多种2D和3D模型液体的分子动力学模拟.
- 分析局部弹性,短暂集群,剪切转换区域和弹性介导的相互作用.
主要成果:
- 过渡弹性集群可以量化地弥合动态异质性和剪切稀释.
- 动态异质性在这些集群的产生后显著出现,由剪切转换区域和弹性相互作用驱动.
- 一个将剪切稀释与动态异质度的长度尺度连接起来的缩放定律被发现.
结论:
- 在瞬态集群中局部弹性是理解超冷液体动态的关键.
- 这提供了一个统一的图片,解释了异质动态和剪切稀释.
- 这些发现为预测和控制压力下的液体行为提供了一个新的框架.
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