Dynamic and steady-state water flux, current density, and resistance across a Nafion 115 membrane-electrode-assembly (MEA) were measured as functions of temperature, water activity, and applied potential. After step changes in applied potential, the current, MEA resistance, and water flux evolved to new values over 3000-5000 s, indicating a slow redistribution of water in the membrane. Steady-s...

this study focuses on the preparation and modification of a thin-film composite (tfc) hollow fiber polyamide membrane fabricated by the interfacial polymerization of piperazine (pip) and trimesoyl chloride (tmc) on a porous polysulfone substrate. the effects of triethylenetetramine (teta) and silica nanoparticles (sio2) contents in the aqueous phase (as the additives) on the morphology and perf...

in this paper, a simplified formulation for compositional reservoir simulator is presented. these types of simulators are used when inter-phase mass transfer depends on phase composition as well as pressure. the procedure for solving compositional model equations is completely described. for equilibrium calculation, property estimation peng robinson equation of state is used. this equation was ...

Monitoring the quality of frying oil is important for the health of consumers. This paper reports a microfluidic technique for rapidly quantifying the degradation of frying oil. The microfluidic device generates monodispersed water-in-oil droplets and exploits viscosity and interfacial tension changes of frying oil samples over their frying/degradation process. The measured parameters were corr...

Interfacial nanobubbles (INBs) on a solid surface in contact with water have drawn widespread research interest. Although several theoretical models have been proposed to explain their apparent long lifetimes, the underlying mechanism still remains in dispute. In this work, the morphological evolution of INBs was examined in air-equilibrated and partially degassed water with the use of atomic f...

Oil droplets loaded with surfactant propel themselves with a velocity up to 6 mm s(-1) when they are placed in an aqueous phase of NaOH solution or buffer solution. The required driving force for such motion is generated on the interface of the droplets by the change in interfacial tension, due to deprotonation of the surfactant. This force induces Marangoni convection, which gives rise to a ci...

Many of the biological processes taking place in cells are mediated by enzymatic reactions occurring in the cell membrane. Understanding interfacial enzymatic catalysis is therefore crucial to the understanding of cellular function. Unfortunately, a full picture of the overall mechanism of interfacial enzymatic catalysis, and particularly the important diffusion processes therein, remains unres...

Waste cooking oil (WCO) is a kind of non-edible oil with enormous quantities and its unreasonable dispose may generate negative impact on human life and environment. However, WCO is certainly a renewable feedstock of bio-based materials. To get the rebirth of WCO, we have established a facile and high-yield method to convert WCO to bio-based zwitterionic surfactants with excellent surface and i...

The digestion of dietary components in the human gastrointestinal (GI) tract is a complex, dynamic, inherently heterogeneous process. A key aspect of the digestion of lipid in the GI tract is the combined action of bile salts, lipase and colipase in hydrolysing and solubilising dispersed lipid. The bile salts are a mixture of steroid acid conjugates with surfactant properties. In order to exami...

Lipases are the most widely employed enzymes in commercial industries. The catalytic mechanism of most lipases involves a step called "interfacial activation". As interfacial activation can lead to a significant increase in catalytic activity, it is of profound importance in developing lipase immobilization methods. To obtain a potential biocatalyst for industrial biodiesel production, an effec...