论文标题
表面电势解释了离子特异性气泡聚结的抑制
The surface potential explains ion specific bubble coalescence inhibition
论文作者
论文摘要
假设：某些离子可以防止在水中聚集起来。已经提出了吉布斯 - 马龙尼的压力作为这种现象的解释。每当存在表面增强或表面耗尽的溶质时，这种排斥压力就会发生在薄膜引流期间。然而，众所周知，气泡结合抑制取决于以特殊且无法解释的方式存在哪些特定的离子组合。这种依赖性可以通过在界面处的离子分布产生的静电表面电势来解释，这将改变离子的自然表面倾向，从而改变吉布斯 - 马龙诺压力。 计算：用于溶质混合物的Gibbs-Marangoni压力的广义形式，并使用改良的Poisson-Boltzmann方程模型来计算由四种不同离子组成的五种不同电解质溶液的压力。 发现：将离子与不同的表面倾向相结合，即增强并耗尽的离子会产生明显的静电表面电势，从而抑制这些离子的自然表面倾向，从而降低了Gibbs-Marangoni压力，从而允许气泡合并。这种机制解释了为什么电解质抑制气泡聚结的能力与纯电解质的表面张力相关，而与混合电解质无关。
Hypothesis: Some ions can prevent bubbles from coalescing in water. The Gibbs-Marangoni pressure has been proposed as an explanation of this phenomenon. This repulsive pressure occurs during thin film drainage whenever surface enhanced or surface depleted solutes are present. However, bubble coalescence inhibition is known to depend on which particular combination of ions are present in a peculiar and unexplained way. This dependence may be explained by the electrostatic surface potential created by the distribution of ions at the interface, which will alters the natural surface propensity of the ions and hence the Gibbs-Marangoni pressure. Calculations: A generalised form of the Gibbs-Marangoni pressure is derived for a mixture of solutes and a modified Poisson-Boltzmann equation model is used to calculate this pressure for five different electrolyte solutions made up of four different ions. Findings: Combining ions with differing surface propensities, i.e., one enhanced and one depleted, creates a significant electrostatic surface potential which dampens the natural surface propensity of these ions, resulting in a reduced Gibbs-Marangoni pressure, which allows bubble coalescence. This mechanism explains why the ability of electrolytes to inhibit bubble coalescence is correlated with surface tension for pure electrolytes but not for mixed electrolytes.
