Capillary pressure of van der Waals liquid nanodrops

The dependence of the surface tension on a nanodrop radius is important for the new-phase formation process. It is demonstrated that the famous Tolman formula is not unique and the size-dependence of the surface tension can distinct for different systems. The analysis is based on a relationship between the surface tension and disjoining pressure in nanodrops. It is shown that the van der Waals interactions do not affect the new-phase formation thermodynamics since the effect of the disjoining pressure and size-dependent component of the surface tension cancel each other.Comment: The paper is dedicated to the 80th anniversary of A.I. Rusano

Wetting films and wetting

Macroscopic approach to the wetting phenomena, based on the isotherms of disjoining pressure of wetting films in equilibrium with concave menisci or drops, allows one to calculate the contact angles for different liquids and solid substrates. The results of calculations are presented using the theory of long-range surface forces, and their agreement with experimental data is shown. The role of the transition zone between the wetting films and bulk liquid in the phenomena of line tension, mechanical and thermodynamical equilibrium, and the formation of dynamic contact angles, is demonstrated. Within the framework of the macroscopic approach the phenomena of prewetting and wetting transition are discussed.Une approche macroscopique des phénomènes de mouillage, basée sur les isothermes de pression de disjonction des films de mouillage en équilibre avec des ménisques concaves ou des gouttes, permet le calcul des angles de contact de divers liquides sur des substrats solides. Nous présentons les résultats de calculs utilisant la théorie des forces de surface à longue portée et nous montrons leur accord avec des données expérimentales. Nous insistons sur le rôle de la zone de transition entre le film de mouillage et le liquide en volume dans l'étude des tensions de ligne, de l'équilibre mécanique et thermodynamique et de la formation des angles de contact dynamiques. Les transitions de mouillage et de prémouillage sont discutées dans le cadre de cette théorie macroscopique