两个时间尺度驱动了一个铁粒体实验中的过渡网络的形成
Ali Lakkis1, Matthias Biersack1, Oksana Bilous2
1Experimentalphysik V, University of Bayreuth, Universitätsstrasse 30, 95447 Bayreuth, Germany. ali.lakkis@uni-bayreuth.de.
Soft matter
|December 8, 2025
概括
在颗粒状混合物中的磁化颗粒在振动下降时形成网络和集群. 这种聚合行为揭示了由磁性易感性和摩擦驱动的两个不同的时间尺度.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 复杂的系统复杂的系统.
背景情况:
- 颗粒状材料在外部刺激下表现出复杂的行为.
- 了解聚合动态对于各种应用至关重要,从工业过程到地质物理现象.
研究的目的:
- 在垂直振动下研究二元颗粒混合物 (玻璃和磁化钢球) 的聚合动态.
- 在震动幅度的变化时,从分散状态转变为聚合状态的转变.
- 确定管理聚合过程的关键因素和时间表.
主要方法:
- 实验是在水平限制的颗粒混合物上进行的.
- 应用了垂直振动,震动幅度突然降低 (灭).
- 结构和网络指标,包括协调号,用于分析粒子排列.
主要成果:
- 震动幅度的突然下降导致磁化颗粒的聚合.
- 深度火导致了一个短暂的透网络,该网络粗化成集群.
- 温和的火直接导致了密集的集群形成,没有中间网络.
- 确定了两个特征的时间表:快速链接和更慢的整体重组.
结论:
- 聚合过程是由磁性易受性和球间摩擦的相互作用所支配的.
- 敏感二极硬球 (SDHS) 模型有效地捕捉了具有两个内在时间尺度的相分离.
- 该研究提供了对颗粒系统相位分离的最小模型的见解.
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