DIRECT EXPERIMENTAL-VERIFICATION OF THE KELVIN EQUATION FOR CAPILLARY CONDENSATION
DIRECT EXPERIMENTAL-VERIFICATION OF THE KELVIN EQUATION FOR CAPILLARY CONDENSATION
复制标题
DOI：
10.1038/277548a0
复制
发表时间：
1979-01-01
期刊：
影响因子：
64.8
通讯作者：
ISRAELACHVILI, JN
中科院分区：
文献类型：
--
作者：
FISHER, LR;ISRAELACHVILI, JN
被困在微孔中或以非常小的高度弯曲的液滴形式存在的液体的热力学性质由开尔文方程描述。该方程构成了临界成核理论2的基础，并已用于解释诸如粘附3、小颗粒2的增强溶解度以及液体在多孔材料中的保留和流动4 -6等多种现象。开尔文方程应用于这种高度弯曲的界面（平均曲率半径可以在1-100 nm的范围内）的有效性受到质疑，但从未通过直接实验进行过测试。我们用多光束干涉法观察了分子光滑云母交叉柱体间毛细凝聚液的形成。本文报道了环己烷分子的平均曲率半径为4 nm的分子链均服从Kelvin方程。我们进一步得出结论，热力学定律的应用，和体积表面张力的概念，是有效的，在原则上，这种高度弯曲的接口。
THE thermodynamic properties of liquids trapped in microscopic pores or existing as very small, highly curved droplets are described by the Kelvin equation1. This equation forms the basis of critical nucleation theory2and has been used in interpreting such diverse phenomena as adhesion3, the enhanced solubility of small particles2and the retention and flow of liquids in porous materials4–6. The validity of the application of the Kelvin equation to such highly curved interfaces (where the mean radius of curvature can be in the range 1–100 nm) has been questioned1,4, but has never been tested by direct experiment. We have used multiple beam interferometry to observe the formation of capillary condensed liquid between crossed cylinders of molecularly smooth mica. We report here that the Kelvin equation is obeyed by cyclohexane menisci with mean radius of curvature as low as 4 nm. We further conclude that the application of the laws of thermodynamics, and the concept of a bulk surface tension, are valid in principle for such highly curved interfaces.