在剪切对齐的活液晶体中,曲折不稳定性和拓动荡
Hend Baza1,2, Fei Chen3, Taras Turiv1,4
1Advanced Materials and Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA. olavrent@kent.edu.
Soft matter
|December 12, 2025
概括
液晶中的鞭状微游体从剪切对齐过渡到拓动荡. 活动力驱动波动,通过分离对释放压力,在活体液晶中创建复杂的动态模式.
科学领域:
- 软物质物理学 软物质物理学
- 活体物质系统是什么
- 液晶的动力学 液晶的动力学
背景情况:
- 活体液晶 (LLC) 是通过在被动液晶介质中分散*B. subtilis*等活性微游体而形成的.
- 了解LLC中从有序状态到动态模式的过渡对于活性物质研究至关重要.
研究的目的:
- 为了研究从剪切强加对齐到拓动荡的过渡,在一个基于*B. subtilis*的LLC.
- 分析活力应力和粘弹性背景在模式形成中的作用.
主要方法:
- 使用一个大尺寸的实验单元来最大限度地减少限制效应.
- 在剪切停止后观察微游泳者诱导的波动和离线对形成的动态.
- 分析能量光谱以了解阴性背景的影响.
主要成果:
- 来自*B. subtilis*的活性力诱导自我放大曲线波动,导致拓缺陷核化.
- 离线对增多,形成拓动荡,具有方向有序的核位点.
- 粘弹性阴性背景影响能量光谱和缺陷动态,在高度活跃的系统中表现出非单调的行为.
结论:
- 应用剪切和被动粘弹性背景显著影响LLC中的活性物质动态.
- 该研究提供了一个实验可访问的活性物质系统的全面描述,将活性应力与新出现的流联系起来.
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