在微游泳器悬浮中伪称数值波动和内马学顺序
Ismail El Korde1, Dóra Bárdfalvy1, Jason M Lewis1
1Lund University, Division of Physical Chemistry, P.O. Box 124, S-221 00 Lund, Sweden.
Physical review letters
|September 15, 2025
概括
在潮湿活性物质中观察到巨型数值波动 (GNF),但与干燥系统不同. 微游泳器中的这些伪GNF是暂时的,且依赖于尺度,质疑液体流中的真实GNF.
科学领域:
- 物理 物理学 物理
- 软物质物理学 软物质物理学
- 活动物质 活动物质
背景情况:
- 巨型数值波动 (GNFs) 具有导向顺序的干活物质的特征.
- 湿活性物质系统,如细菌悬浮液,在实验中显示出增强的波动,但缺乏GNF的理论预测.
研究的目的:
- 在3D悬浮的推杆微游泳器数值调查超高斯数值波动的出现.
- 确定这些波动出现的条件及其与集体运动和细菌性质的关系.
主要方法:
- 推力微游泳器的三维悬挂的数值模拟.
- 分析粒子数量的波动及其对细菌持久长度和系统长度尺度的依赖性.
主要成果:
- 超高斯数值波动出现在微游泳者悬浮中,位于过渡到集体运动的上方.
- 这些波动取决于细菌持久长度 (lp),并且发生在比阴性斑块大小 (ξ) 小的长度尺度上.
- 观察到的波动被称为"伪GNF",因为它们是短暂的和规模依赖的,与真正的GNF不同.
结论:
- 生物活性物质的增强密度波动可能是短暂的效应,在超越美索斯科普尺度的衰变.
- 这些发现表明,具有普遍性质的"真正"GNF可能在流体环境中受到限制.
- 这项研究提出了关于GNF在保持动量的活性物质系统中的存在和普遍性的问题.
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