in the present study, the potential of a bacterial consortium of enterobacter cloacae and pseudomonas sp. (ercppi-2) for microbial enhanced oil recovery was investigated. various mechanisms of enhanced oil recovery (eor) as a result of using ercppi-2 and its metabolic products were studied in detail. the obtained results showed that under simulated reservoir conditions, interfacial tension redu...

In this work, we derive the asymptotic expansion of the velocity field of a small deformable droplet immersed in an incompressible Newtonian fluid. Using an appropriate physical scaling of the surface tension with respect to the droplet volume we show that the first order of the asymptotic can be expressed in terms of the velocity field in absence of the droplet and a new kind of moment tensor ...

Liquid:vapor and liquid:liquid interfaces exhibit complex organizational structure and dynamics at the molecular level. In the case of water and organic solvents, the hydrophobicity of the organic, its conformational flexibility, and compressibility, all influence interfacial properties. This work compares the interfacial tension, width, molecular conformations and orientations at the vapor and...

The well-known alcoholic beverage Pastis becomes turbid when mixed with water due to the poor solubility of trans-anethol, the anise-flavored component of Pastis in the water solution formed. This destabilization appears as the formation of micrometer-sized droplets that only very slowly grow in size, thus expanding the life of the anise-flavored beverage. The slow growth has been attributed to...

The properties of interfaces are discussed between coexisting phases in phase separated aqueous solutions of polymers. Such interfaces are found in food, where protein-rich and polysaccharide-rich phases coexist. Three aspects of such interfaces are highlighted: the interfacial profiles in terms of polymer composition and polymer concentration, the curvature dependence of the interfacial tensio...

We present measurements of equilibrium forces resulting from capillary condensation. The results give access to the ultralow interfacial tensions between the capillary bridge and the coexisting bulk phase. We demonstrate this with solutions of associative polymers and an aqueous mixture of gelatin and dextran, with interfacial tensions around 10 microN/m. The equilibrium nature of the capillary...

Dissolution of a solute molecule into a solvent necessitates the creation of a cavity devoid of solvent molecules. The cavity solvation free energy is exactly known at both very small and large length scales, but in between it can only be estimated by various approximations. Guided by simulation results for the solvation of small cavities and density functional theory, we analyze the size depen...

Molecular dynamics simulations are used to study capillary adhesion from a nanometer scale liquid bridge between two parallel flat solid surfaces. The capillary force, Fcap, and the meniscus shape of the bridge are computed as the separation between the solid surfaces, h, is varied. Macroscopic theory predicts the meniscus shape and the contribution of liquid/vapor interfacial tension to Fcap q...

We have used molecular dynamics simulations with coarse-grained and atomistic models to study the lateral pressure profiles in lipid monolayers. We first consider simple oillair and oil/water interfaces, and then proceed to lipid monolayers at air/water and oil/water interfaces. The results are qualitatively similar in both atomistic and coarse-grained models. The lateral pressure profile in a ...

The interfacial tension between immiscible liquids is studied as a function of a model linear surfactant length and concentration using coarse-grained, dissipative particle dynamics numerical simulations. The adsorption isotherms obtained from the simulations are found to be in agreement with Langmuir's model. The reduction of the interfacial tension with increasing surfactant concentration is ...