双重刚性过渡决定了干燥合液滴的命运
Matteo Milani1, Ty Phou1, Christian Ligoure1
1Laboratoire Charles Coulomb (L2C), Université Montpellier, CNRS, Montpellier, France. laurence.ramos@umontpellier.fr.
Soft matter
|September 4, 2023
概括
干燥的体液滴形成外,可以变得不稳定. 这项研究揭示了两个不稳定性:可逆的玻璃过渡和永久的聚合,取决于蒸发速度,进步了解体干燥.
科学领域:
- 合体和表面科学科学
- 材料科学 材料科学 材料科学
- 流体动力学 流体动力学
背景情况:
- 体悬浮蒸发对于粉末生产和了解病原体生存等应用至关重要.
- 蒸发的水滴形成外,可以变得不稳定,但这些机制尚未完全理解,尤其是在较低的蒸发速度下.
研究的目的:
- 为了研究不同蒸发速率的疏水表面上的合液滴干燥的形状不稳定性.
- 阐明这些不稳定的潜在机制,特别是粒子聚合和动态的作用.
主要方法:
- 结合宏观成像与纳米粒子动态的空间和时间分辨率测量.
- 监控外厚度,颗粒分布和滴滴干燥期间的移动性.
- 在不同的蒸发条件下,对疏水表面的分析滴滴.
主要成果:
- 确定了两种不同的形状不稳定性,发生在值蒸发率以上:化和裂.
- 观察到与第二个不稳定性 (裂) 相关的永久纳米粒子聚合.
- 发现了一个新的,可逆的玻璃过渡的外之前的第一个不稳定性 (阴道).
结论:
- 该研究提供了一个统一的状态图,用于在疏水表面干燥合液滴.
- 根据蒸发速度区分可逆和不可逆的粒子聚合机制.
- 为各种应用提供了控制合体外形成的新见解.
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