通过浮力和棒跳溶解的相互作用发射一个滴
Binglin Zeng1, Haichang Yang1,2, Ben Bin Xu3
1Department of Chemical and Materials Engineering, University of Alberta, Edmonton, T6G 1H9, Canada.
Small (Weinheim an der Bergstrasse, Germany)
|September 19, 2023
概括
一滴溶解聚合物溶液在水中只有在显著收缩后才升起,这违背了典型的浮力原理. 这种现象是由棒跳溶解动力学和足够的浮力力量驱动的,用于可编程的落下运动.
科学领域:
- 物理化学 物理化学
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
背景情况:
- 阿基米德的原理通常规定浮力取决于物体的大小和相对于流体的密度.
- 在溶液中溶解物体可以表现出由化学反应和流体相互作用影响的复杂行为.
- 了解掉落动态对于微流体和材料加工中的应用至关重要.
研究的目的:
- 为了研究一种新奇的现象,即溶解滴在水性酸溶液中呈现延迟升高.
- 阐明控制溶解滴自发上升运动的关键物理机制.
- 为了探索这种可编程下降起的潜力,用于微尺度工程应用.
主要方法:
- 观察和分析一种溶解的聚合物溶液在酸性水性介质中的基质上掉落.
- 滴溶解,微滴形成和与周围流体相互作用的表征.
- 确定影响下降动态的关键因素,包括跳杆行为和阿基米德数.
主要成果:
- 溶解滴只有在达到显著较小的大小后才会升起,这与预期的浮力行为相反.
- 跌升是由棒跳溶解和足够的浮力力 (阿基米德数>1) 的组合启动的.
- 滴水上升的时间可以通过初始滴水大小及其化学反应速度来控制.
结论:
- 已经发现了一个可编程滴升的新机制,由化学溶解和流体动力学驱动.
- 这种现象为密集介质中微观物体的控制运动提供了一种新的方法.
- 潜在的应用包括微流体学,微机器人学和设备工程,利用自发掉落脱离.
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