在薄膜中稳定状模式,这是由于活性悬浮的剪切加厚造成的
Henning Reinken1, Andreas M Menzel1
1Institut für Physik, Otto-von-Guericke-Universität Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany.
Physical review letters
|April 13, 2024
概括
剪切加厚液体中的活跃微游泳体自我组织成稳定的旋模式. 这种新的方法可以为薄膜和膜等应用程序提供精确的微米级结构.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 软物质物理学 软物质物理学
背景情况:
- 在微米尺度上的结构材料对于先进的应用,包括音声设备至关重要.
- 微游泳器悬浮中的活跃流通常会导致混乱状态.
研究的目的:
- 开发一种新的方法,以在活性悬浮中实现规律的微米级结构化.
- 探索在剪切加厚液体中的活性物质的自我组织.
主要方法:
- 使用含有活性微游泳剂的剪切加厚载体液.
- 观察流体的自我组织,形成稳定的旋模式.
- 引入中等大小的被动粒子来研究它们的空间组织.
主要成果:
- 剪切加厚液体中的活跃流本质上稳定了正规的 vortex 模式.
- 活性悬浮物自组织成一个周期性的,不平衡的结构状态.
- 被动粒子是由新出现的流体结构空间组织的.
结论:
- 这种方法通过薄膜和膜的图案设计为功能化提供了一条新的途径.
- 自组织现象为受控微米尺度结构提供了一条途径.
- 利用特定流体中的活跃流,可以实现可预测的材料组织.
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