in this work, the interfacial interfacial polymerization (ip) technique was employed using terephthaloyl chloride (tpc) and p-phenylenediamine (ppd), as reactant monomers, to prepare poly(paraphenylene terephthalamide) thin film composite (tfc) nanofiltration on polyethersulphone (pes) support layer. the effects of six different anionic and non-ionic surfactants, in the aqueous phase on the mor...

The basis for tight binding of bee venom phospholipase A2 (bvPLA2) to anionic versus zwitterionic phospholipid interfaces is explored by charge reversal mutagenesis of basic residues (lysines/arginines to glutamates) on the putative membrane binding surface. Single-site mutants and, surprisingly, multisite mutants (2-5 of the 6 basic residues mutated) are fully functional on anionic vesicles. M...

A simple modality is suggested to include, in the framework of a modified Poisson-Boltzmann approach, specific ion effects via the change in the ion hydration between the bulk and the vicinity of the surface. This approach can account for both the depletion of the interfacial region of structure-making ions as well as for the accumulation of structure-breaking ions near the interface. Expressio...

We report a numerical study of equilibrium phase diagrams and interfacial properties of bulk and confined colloid-polymer mixtures using grand canonical Monte Carlo simulations. Colloidal particles are treated as hard spheres, while the polymer chains are described as soft repulsive spheres. The polymer-polymer, colloid-polymer, and wall-polymer interactions are described by density-dependent p...

Nematic-isotropic interfaces exhibit novel dynamics due to anchoring of the liquid crystal molecules on the interface. The objective of this study is to demonstrate the consequences of such dynamics in the flow field created by an elongated nematic drop retracting in an isotropic matrix. This is accomplished by two-dimensional flow simulations using a diffuse-interface model. By exploring the c...

Nematic liquid crystals at rough and fluctuating interfaces are analyzed within the Frank elastic theory and the Landau-de Gennes theory. We study specifically interfaces that locally favor planar anchoring. In the first part we reconsider the phenomenon of Berreman anchoring on fixed rough surfaces, and derive new simple expressions for the corresponding azimuthal anchoring energy. Surprisingl...

the chemical surfactant flooding can mobilize the trapped oil by lowering the interfacial tension between oil and brine and in some cases altering the reservoir rock wettability. in this work, the effect of surfactants on oil/brine interfacial tension was experimentally investigated. first, the effect of surfactants concentration was surveyed. afterwards, the effect of salinity on surfactant be...

the aim of this research is to investigate the effect of carbon fiber reinforced polymer (cfrp) composite fabric on monotonic and fatigue behaviors of reinforced concrete beams. to control the failure occurrence, a small notch was induced at the middle span in bottom surface for all of the studied rc specimens. totally 12 beams were tested from which 6 beams tested under monotonic and 6 other t...

Primary rate and equilibrium parameters for 60 site-directed mutants of bovine pancreatic phospholipase A2 (PLA2) are analyzed so incremental contributions of the substitution of specific residues can be evaluated. The magnitude of the change is evaluated so a functional role in the context of the N- and C-domains of PLA2 can be assigned, and their relationship to the catalytic residues and to ...