显而易见的结构异质,源于颗粒接近零的无球性,在颗粒状球圆包装中
Yuwen Sun1, Chenyang Wang1, Jing Yang1
1Shanghai Key Laboratory of Magnetic Resonance, School of Physics and Electronic Science, <a href="https://ror.org/02n96ep67">East China Normal University</a>, Shanghai 200241, China.
Physical review. E
|August 20, 2024
概括
在颗粒状材料中微粒的微粒球性令人惊地改变了排序. 全球阴性秩序随着包装分数的减少而下降,与局部接触异性质形成对比,影响结构重组.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 统计力学 统计力学
背景情况:
- 颗粒状材料表现出由粒子形状和包装影响的复杂行为.
- 了解颗粒系统中的结构异质性对于预测材料性质至关重要.
研究的目的:
- 为了研究微小粒子无球性对颗粒包装的结构秩序和机械反应的影响.
- 探索粒子形状,包装分数和新出现的结构异构形态之间的关系.
主要方法:
- 磁共振成像 (MRI) 实验被用来研究球体圆柱体的颗粒包装.
- 分析的重点是跨各种长度尺度和粒子接触性质的结构性异质.
主要成果:
- 确定了重要的结构异质,即使在2%的不球性.
- 观察到,随着包装分数的增加,全球阴性顺序的减少,而局部接触异构性增加.
- 在接触层和中等层结构之间发现了不可忽视的相关性,导致与球体相比不同的非亲系重排.
结论:
- 微小的粒子无球性诱导了反直觉的排序现象,由重力,摩擦和几何挫折的竞争效应驱动.
- 这些发现突出了颗粒系统中粒子形状,摩擦和外部场之间的复杂相互作用.
- 结果可以为含有非球形颗粒的颗粒材料的统计机械模型提供信息和改进.
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