Self-assembled lamellar silica-surfactant mesophase composites have been prepared with crystal-like ordering in the silica frameworks using a variety of cationic surfactant species under hydrothermal conditions. These materials represent the first mesoscopically ordered composites that have been directly synthesized with structure-directing surfactants yielding highly ordered inorganic framewor...

Gemini surfactants, with double hydrophilic and hydrophobic groups, offer potentially orders of magnitude greater surface activity compared to similar single unit molecules. A cationic Gemini surfactant (Propyl didodecyldimethylammonium Bromide, PDDDAB) and a conventional cationic surfactant (Dodecyltrimethylammonium Bromide, DTAB) were used to pre-treat and generate activated carbon. The remov...

Textile wetting involves the displacement of air by surfactant solutions in the fiber matrix. The kinetics of surfactant adsorption is more important than the equilibrium properties of surfactant solutions for the textile wetting process because equilibrium conditions are rarely attained during the time allowed for wetting in textile processing.' Fowkes observed that the log of the wetting time...

The interactions two synthetic triazinyl reactive dyes Mono-s-chloro Triazinyl reactive dyes DI and DII with the cationic surfactant N-hexadecyl pyridinium chloride CPC were studied using a conductometric method in 25, 30, 35, 40 and 45ºC. The equilibrium constants and other thermodynamic parameters for the ion pair formation were calculated on the basis of a theoretical model using the data ob...

Environmental context The molecular organisation of humic substances is key to understanding various natural and engineered processes, such as metal speciation bioavailability. Two main models have been proposed: polymeric supramolecular organisation. A physicochemical approach, based on the interaction acid with increasing amounts cationic surfactants, leads a sequence structures that provides...

composite electrodeposition is a low-cost and low-temperature method, which is used to make metal matrix composite coatings. in this study the surfactant of anionic(sds) and cationic (ctab) is used as additive in composite coating of ni/tin. the results showed that the anionic surfactant caused more particles in the composite coatings. increasing sds concentration to the optimal value leads to ...

Cationic gemini surfactant dimethylene-1,2-bis(dodecyldiethylammonium bromide), referred to as C12C2C12(Et) was synthesized, and its surface property and aggregation behavior in aqueous solution were studied. The value of γ at the critical micelle concentration (γcmc) is much smaller than that of the surfactant homologues with longer spacer. Spherical and elongated micelles were formed in the a...

We study a simple model of DNA divalent cationic surfactant complexation. We find that the combination of electrostatic and hydrophobic effects leads to a cooperative phenomenon in which as the amphiphile is added to the solution containing DNA, a large fraction of the DNA’s charge is neutralized by the condensed divalent cationic surfactants, forming the surfoplex. This binding transition occu...

An acetylene black electrode modified by an adsorbed cationic surfactant, cetyltrimethylammonium bromide (CTAB), was developed. The influences of various types of surfactants on the electroreduction of O2 were investigated. It was demonstrated that a cationic surfactant, CTAB, on the surface of the electrode could significantly decrease the overpotential of dioxygen reduction, and the reduction...

Using dissipative particle dynamics (DPD) simulations, we explore the specifics of micellization in the solutions of anionic and cationic surfactants and their mixtures. Anionic surfactant sodium dodecyl sulfate (SDS) and cationic surfactant cetyltrimethylammonium bromide (CTAB) are chosen as characteristic examples. Coarse-grained models of the surfactants are constructed and parameterized usi...