The Enhanced Oil Recovery (EOR) process is one of the ways in petroleum exploitation so that thick oil can be lifted to surface and produced. EOR referred this study carried out previous studies at laboratory UPN Veteran Yogyakarta Indonesia by adding biosurfactants adjusting temperature. In experiments, each time an amount biosurfactant concentration added temperature adjusted, calculation mus...

Bacterial adhesion to epithelial surfaces affects retention time in the human gastro-intestinal tract and therefore significantly contributes to interactions between bacteria and their hosts. Bacterial adhesion among other factors is strongly influenced by physico-chemical factors. The accurate quantification of these physico-chemical factors in adhesion is however limited by the available meas...

Two recent studies (Denkov et al., Nature 2015, 528, 392 and Guttman et al. Proc. Natl. Acad. Sci. U.S.A.2016, 113, 493) demonstrated that micrometer-sized n-alkane drops, dispersed in aqueous surfactant solutions, can break their spherical symmetry upon cooling and self-shape into a variety of regular shapes, such as fluid polyhedra, platelet-shaped hexagons, triangles, rhomboids, toroids, and...

Measurements of the ultralow interfacial tension and surfactant film bending rigidity for micron-sized heptane droplets in bis(2-ethylhexyl) sodium sulfosuccinate−NaCl aqueous solutions were performed in a microfluidic device through the analysis of thermally driven droplet interface fluctuations. The Fourier spectrum of the stochastic droplet interface displacement was measured through bright-...

We report numerical and experimental studies on a droplet moving through an array of mirofluidic ratchets. Droplets are formed at a T junction and subsequently forced through microfluidic ratchets in the form of diffuser/nozzle structures. At the same flow rates of the continuous and the dispersed phases, the velocity of the droplet is determined by the viscosity of the continuous phase and the...

We present a method to control the interfacial tension of a liquid alloy of gallium via electrochemical deposition (or removal) of the oxide layer on its surface. In sharp contrast with conventional surfactants, this method provides unprecedented lowering of surface tension (∼ 500 mJ/m(2) to near zero) using very low voltage, and the change is completely reversible. This dramatic change in the ...

The aim of this work was to evaluate the interfacial tension from the poly(butylene terephtalate) and poly(styrene-co-acrylonitrile) (PBT/SAN) interface region using the drop retraction method. SAN filaments were sandwiched between two PBT films; the whole system was heated up to 240 °C, in a hot stage coupled to an optical microscope. The rheological parameters of the PBT/SAN system were obtai...

Measurements of the ultralow interfacial tension and surfactant film bending rigidity for micron-sized heptane droplets in bis(2-ethylhexyl) sodium sulfosuccinate-NaCl aqueous solutions were performed in a microfluidic device through the analysis of thermally driven droplet interface fluctuations. The Fourier spectrum of the stochastic droplet interface displacement was measured through bright-...

The effect of dilute, insoluble surfactant on the deformation and breakup of a viscous drop is examined. Two cases are considered: the deformation and stretching of a drop in a uniaxial extensional flow and the surface-tension-driven motion of an elongated drop in a quiescent fluid. Aside from resealing the mean capillary force through an average decrease in the interfacial tension, surfactants...

Droplet formation in the presence of nanoparticles was studied in a T-shaped microfluidic device numerically. Nanoparticles in continuous phase did not influence droplet formation dynamics obviously. Contrarily, the presence of nanoparticles in dispersed phase will influence evidently droplet formation dynamics, likely reasons are the accumulation of nanoparticles at the liquid-liquid interface...