In the present paper, we aim to investigate the dependence of surface tension on the surface properties and reveal the counter-ion effects on the adsorption of ionic surfactants on the solution surface. The surface tension, surface excess and surface concentration (defined as the amount of surfactant adsorbed in the surface phase divided by the surface area) of two anionic surfactants, namely d...

......................................................................................................................................... x Chapter 1: Introduction to Capillary Driven Microfluidics ..................................................... 1 1.1 Surface Tension-Confined Microfluidics ........................................................................ 1 1.2 Capillary-Driven Micr...

this work studies the biosurfactants production which enables the diesel biodegradation byusing mixed microbial consortia from polluted sites. it was carried out by culturing three microbial consortia(named as xa, xb and xc) obtained from polluted soils, and enriched in diesel as sole carbon source.batchexperiments were done to study the effects of three variables (temperature,hydrocarbon conce...

dam spillways are the structures that lead rightly and safely the outflow downstream, so that the dam integrity can be guaranteed. many accidents with dams have been caused by an inadequate spillway design or insufficient capacity. to accurately respond the hydraulic spillways, designers use physical modeling for designing this kind of structures. the scale effect in the spillway modeling, as a...

The method of matched asymptotic expansions is used to solve for the free surface of a thin liquid drop draining down a vertical wall under gravity. The analysis is based on the smallness of the surface tension term in the lubrication equation. In a region local to the front of the drop, where the surface curvature is large, surface tension forces are significant. Everywhere else, the surface c...

We perform energy estimates for a sharp-interface model of two-dimensional, twophase Darcy flow with surface tension. A proof of well-posedness of the initial value problem follows from these estimates. In general, the time of existence of these solutions will go to zero as the surface tension parameter vanishes. We then make two additional estimates, in the case that a stability condition is s...

Surface tension (ST) measurements were carried out on various binary mixtures of the "normal" surfactants, such as nonionic surfactant, hexaethylene glycol mono-n-dodecyl ether(C12EO6), and cationic surfactant, tetradecyltrimethylammonium bromide (TTAB), and polymeric copolymer, Pluronic F127, F127(PPO)-g-PVP, and F127(PEO)-g-PVP. In all cases mixed micellar aggregates were formed and critical ...