The formation and disappearance of liquid bridges between two surfaces can occur either through equilibrium or nonequilibrium processes. In the first instance, the bridge molecules are in thermodynamic equilibrium with the surrounding vapor medium. In the second, chemical potential gradients result in material transfer; mechanical instabilities, because of van der Waals force jumps on approach ...

Measurements of solubility and vapor pressure indicate that the cost of making a cavity in a nonpolar solvent that is large enough to accommodate a single water molecule is just balanced by the attraction between the water molecule and the walls of the cavity. As a result of this unexpected coincidence, the equilibrium constant for entry of an isolated water molecule from the vapor phase into c...

A numerical framework has been proposed to model the interacting effects of mixture non-ideality and mass transfer on hydrodynamics of a multiphase system using CFD methods.Mass transfer during condensation and vaporization is modeled by chemical potential at the liquid-vapor interface. Species mass transfers are related to the diffusion at the interface which in turn is related to the conc...

A heterogeneous nucleation of a vapor bubble on a solid surface was simulated by the molecular dynamics method. Liquid argon between parallel solid surfaces was gradually expanded, until a vapor bubble was nucleated. Argon liquid was represented by 5488 Lennard-Jones molecules and each surface was represented by three layers of harmonic molecules with the constant temperature heat bath model. W...

In biodiesel production processes using supercritical methanol, the phase equilibria for methanol + fatty acid methyl ester systems near the critical temperature of methanol (Tc = 512.6 K) are required as the fundamental data. A flow type method was applied to measure the vapor-liquid equilibria for methanol + fatty acid methyl ester binary systems at 493 – 543 K. The phase behavior was studied...

We report Monte Carlo simulations that show both vapor-liquid and closed-loop liquid-liquid equilibrium in a pure substance, for a model fluid that forms orientation-dependent intermolecular bonds. This is the first time that direct evidence of liquid-liquid immiscibility in a pure fluid has been found using exact methods. Because the model is formulated in terms of a tetrahedrally coordinated ...

A proper understanding of reservoir fluid phase behavior is the first crucial step in the development and production of an oil/gas field. This paper addresses the challenges and errors associated with the fluid sampling that may arise before, during and after the sampling operation. For this aim, DST and PVT data of exploration and production wells of a supergiant offshore gas condensate reserv...

A solid-phase microextraction (SPME) procedure was evaluated for its application in measuring solute release in the headspace (HS) and in the liquid phase (DI) from emulsified and nanostructured materials. Limonene, a hydrophobic flavor compound present in many foods and beverages, was used as a model solute for evaluating the SPME method. Sampling conditions, including SPME fiber type, samplin...