盐度对密集的合物悬浮液的流动的影响
Marc Lagoin1,2, Agnès Piednoir1, Rémy Fulcrand1
1Universite Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, UMR5306, F-69100, Villeurbanne, France. antoine.berut@univ-lyon1.fr.
Soft matter
|April 2, 2024
概括
将盐添加到密集的二氧化颗粒悬浮液中会减缓雪崩,并增加流动的临界角度. 这项研究探讨了盐度对微流体系统流动动力学的影响.
科学领域:
- 合体和表面科学科学
- 软物质物理学 软物质物理学
- 微流体学 微流体学
背景情况:
- 密集的环状悬浮物表现出复杂的流动动力学.
- 由表面电荷控制的粒子相互作用会影响悬浮的行为.
- 微流体装置允许精确控制和观察颗粒流.
研究的目的:
- 为了研究盐度对密集的二氧化颗粒悬浮液的流动动力学的影响.
- 了解离子选如何影响雪崩的行为和微流体桶中的爬行.
- 为了将流动性质的变化与粒子相互作用和包装分数相关联.
主要方法:
- 使用微流体桶与微米大小的二氧化颗粒进行实验研究.
- 悬浮液中的盐度的系统变化.
- 观测流动的动态,包括雪崩的出现和爬行.
- 同焦显微镜测量初始包装分数.
- 原子力显微镜 (AFM) 用于量化表面粗度和粒子间的力.
主要成果:
- 在纯水中,悬浮物在临界角度 (∼5°) 以上表现出"无摩擦"的流动,下方的爬行速度较慢.
- 添加盐增加了临界角度 (高达20°),并引入了雪崩之前的时间延迟.
- 缓慢的爬行模式在很大程度上不受盐度的影响.
- 盐度增加导致更高的初始包装分数和有效的粒子间摩擦.
结论:
- 离子选显著改变了密集的悬浮液的流动动态,主要影响了快速的雪崩状态.
- 观察到的变化归因于由于减少静电排斥而增加的粒子摩擦和打包分数.
- 微流体实验与显微镜相结合,提供了对系统依赖盐的质系统的洞察.
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