Deegan RD, Bakajin O, Dupont TF, Huber G, Nagel SR, Witten TA
James Franck Institute, 5640 South Ellis Avenue, Chicago, Illinois 60637, USA.
Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics. 2000 Jul;62(1 Pt B):756-65. doi: 10.1103/physreve.62.756.
Solids dispersed in a drying drop will migrate to the edge of the drop and form a solid ring. This phenomenon produces ringlike stains and occurs for a wide range of surfaces, solvents, and solutes. Here we show that the migration is caused by an outward flow within the drop that is driven by the loss of solvent by evaporation and geometrical constraint that the drop maintain an equilibrium droplet shape with a fixed boundary. We describe a theory that predicts the flow velocity, the rate of growth of the ring, and the distribution of solute within the drop. These predictions are compared with our experimental results.
分散在干燥液滴中的固体将迁移到液滴边缘并形成固体环。这种现象会产生环状污渍，并且在各种表面、溶剂和溶质中都会出现。在此我们表明，迁移是由液滴内部的向外流动引起的，这种流动是由蒸发导致的溶剂损失以及液滴在固定边界下保持平衡液滴形状的几何约束所驱动的。我们描述了一种理论，该理论可以预测流速、环的生长速率以及溶质在液滴内的分布。这些预测结果与我们的实验结果进行了比较。
