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一名马兰戈尼游泳运动员在1D封闭状态下推动一个粒子
Abhradeep Maitra1, Anupam Pandey2, Sebastien Michelin3
1Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853, USA. am3326@cornell.edu.
Soft matter
|October 29, 2025
概括
活性物质游泳者和被动粒子之间的相互作用揭示了两个不同的运动模式. 增加的粒子密度会减缓游泳者的速度,这是由于阻力造成的,正如坎佛注入的磁盘实验所显示的那样.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 活性物质系统表现出自发的自我推进,在医疗保健和环境可持续性方面有潜在的应用.
- 马兰戈尼游泳器是一种合成活性物质,对于研究活性物质物理学至关重要.
- 以前的研究集中在活性物质如何影响被动粒子,而不是相反.
研究的目的:
- 实验性地研究被动粒子相互作用对活性物质游泳者的自我推进的影响.
- 分析活跃游泳者的独特运动模式和速度变化,以应对不同的被动粒子密度.
主要方法:
- 使用花注入的亚加罗斯盘作为活跃的游泳者和空洞的玻璃微球作为被动的粒子.
- 在环状通道内进行实验,在受控条件下观察游泳者的行为.
- 分析了游泳者的运动,根据初始包装分数确定了稳定和振荡模式.
主要成果:
- 观察到两个不同的运动模式:在低包装分数 (0.45) 中稳定的单向运动和在高分数 (0.45) 中的振荡式来回运动.
- 在低分数时,游泳者拖了粒子,导致速度降低,由于阻力而增加了包装分数.
- 开发了一种简化的力量平衡模型,准确地反映了游泳者速度的实验趋势.
结论:
- 活跃游泳者和被动粒子之间的相互作用动态显著影响游泳者的自我推进和运动模式.
- 包装分数是决定单向和振荡运动模式之间的过渡的关键参数.
- 这些发现提供了对活性物质系统及其集体行为物理学的见解,对设计微型和纳米机器有意义.
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