一个动态系统的方法来放松玻璃形成液体中的放松
Jack F Douglas1, Qi-Lu Yuan2,3, Jiarui Zhang4
1Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA. jack.douglas@nist.gov.
Soft matter
|November 8, 2024
概括
经典热力学在凝聚材料方面面临着挑战. 本研究探讨了多步放松过程,重点关注α-放松时间,以提高对物质平衡动态的理解.
科学领域:
- 热力学和统计力学的热力学.
- 凝聚物质物理学 凝聚物质物理学
- 动态系统理论 动态系统理论
背景情况:
- 经典热力学和统计力学理论 (吉布斯,博尔茨曼) 具有具有有限适用性的公理假设.
- 偏离经典理论需要改进数学和物理基础,特别是对于低温和高密度的凝聚材料.
- 现有的理论很难准确地描述复杂物质系统中的放松过程.
研究的目的:
- 为热力学和统计力学理论开发改进的数学和物理基础.
- 研究在具有挑战性的条件下 (低T,高密度) 适用于凝结材料的扩展.
- 适应动态系统方法来估计冷却液体和晶体的放松时间.
主要方法:
- 专注于凝聚材料系统的最小模型,包括费米-乌拉姆-帕斯塔-辛古模型.
- 利用简化模型的数值和分析处理来阐明放松过程.
- 适应动态系统方法,将系统识别为弱不可集成的动态系统.
主要成果:
- 观察到一个一般的多步放松过程:快速的β-放松,随后是α-放松.
- 确定了α-放松时间 (τ_α) 作为控制物质平衡的主要参数.
- 证明了简化动态系统的动态类似于冷却液体和加热晶体的放松动态.
结论:
- 该研究提供了一种动态系统方法,以了解和估计凝结材料中的放松时间.
- 这种方法特别适用于传统理论失败的条件.
- 这些发现为分析物质平衡和动态提供了更强大的框架.
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