Effects of binary mixtures of ionic/nonionic (sodium dodecyl sulfate/2-heptanol or 1-decanol) and nonionic/nonionic SURFACTANTS (2-heptnol/1-decanol) on drop/interface coalescence of water drops in a continuous n-heptane phase were examined. The drop size reduced appreciably and the multi-step coalescence was suppressed finally as the concentration of each of the constituting components of surfactant mixture was increased. The drop became more stable in comparison to single surfactant systems. It was concluded that the MIXED SURFACTANTS were much more effective on coalescence time and drop lifetime than single surfactant, particularly when one of the components was soluble in the drop phase.

Effect of SURFACTANTS and cellulose enzyme on deinking MIXED office waste paper was studied. To that end, a combination of waste paper accounting for 60% printing paper and 40% copy paper was applied. Then, samples of paper pulp were deinked using four types of cellulose, Surfactant and sodium silicate. The types and the proportion of the chemicals used in the study are as follows: a) Surfactant, b) Cellulase, 0% and 0.6 % were added based on the weight of paper pulp together with a surfactant. c) Sodium silicate with the fix amount of 0.3% of the weight of the paper pulp was used in the process. Different samples of paper pulp influenced by 24 compounds comprising enzymes and chemicals were deinked and the efficiency of the materials was calculated after the process. Following that, all the paper pulp samples were turned into hand-made papers and then indices such as brightness, dirt (quality and quantity of dirt) were studied. The results showed that the type of surfactant and cellulose enzyme affect brightness, dirt index and deinking efficiency.Maximum brightness was with nonyl phenol ethoxylate and fatty alcohol ethoxylate without cellulose enzyme.Minimum dirt index was with nonyl phenol ethoxylate and cellulose enzyme.Also, using nonyl phenol ethoxylate and fatty alcohol ethoxylate result in maximum deinking efficiency.

The effect of salt concentration on thermodynamic stability of aggregations in anionic and cationic-rich mixtures of CTAB (cetyltrimethylammonium bromide) and SDS (sodium dodecyl sulfate) were investigated using conductometryand surface tension. The micellization free energy (DGmic) by critical micellization concentration (CMC) and degree of counter ion binding were determined. The results showed that the formation of MIXED aggregates was more spontaneous in anionic-rich than cationic rich region. Also, electrostatic repulsion between head groups was reduced by using salt addition and micelle was formed. It was observed that, for both the planar air/aqueous interface and micellar systems, the nonideality decreased as the amount of electrolyte in the aqueous medium was increased. This was attributed to a decrease of the surface charge density caused by increasing the concentration of bromide ions. Also, the thermodynamic stability of micelles in presence of salt for removing oily dirt was investigated.

Background and purpose: This study investigated the effect of different HLBs on thesenanoparticles using spironolactone solid lipid nanoparticles. Materials and methods: The spironolactone loaded SLN was prepared by emulsion/solventevaporation technique followed by ultrasonication. In this study, Palmitic acid was used as carrier. Different weight ratio of drug, carrier, Span60 and Tween80 were selected. Different formulations wereprepared with different HLBs. Nanoparticle properties like particle size, polydispersity index, zetapotential and entrapment efficiency were investigated. Optimum formulation was chosen for evaluation ofdrug release and other properties of nanoparticles by DSC and FT-IR spectroscopy. Results: Increasing lipid concentration resulted in consequent increase entrapment efficiency andthe size. Also, the F1-F9 formulations showed that Zeta potential was in an acceptable range, and onlyreduce in HLB in F4 was accompanied with decreasing Zeta potential. Spironolactone was found to havea higher drug release rate in the SLN form. Information from the FT-IR spectroscopy and the DSCthermogram indicated effective entrapment of drug in the carrier. Conclusion: spironolactone-SLNs provide a controlled and increased drug release rates. Spironolacton-SLN would provide high drug levels at the site of action, therefore, this product could beuseful in topical drug delivery.

SURFACTANTS consist of two distinct building blocks, a hydrophilic (lipophilic) and a hydrophobic (lipophilic). The longer the hydrocarbon chain, the greater the tendency to adsorb on the joint surface of the two phases, resulting in more surface tension. Because the SURFACTANTS are hydrophilic and hydrophobic, the presence of these two species stabilizes the surface layers and thus the system. . The purpose of this study is to determine how to measure SURFACTANTS.

An effective method for the preparation of stable dispersions of graphene is the direct exfoliation of graphene from graphite flakes in the aqueous solution of SURFACTANTS. Physical adsorption of SURFACTANTS on graphene surfaces is an important step in dispersing and stabilizing exfoliated graphene sheets in the aqueous medium. Dispersion of graphene with a mixture of SURFACTANTS is an effective way to obtain stable graphene sheets. The effect of synergism on a mixture of SURFACTANTS can reduce the total concentration of SURFACTANTS required for a particular application. The present study employed molecular dynamics simulation to investigate the adsorption of MIXED cationic-rich and anionic-rich SURFACTANTS onto armchair graphene. We investigated the effects of temperature, electrolyte, and alcohol in the aqueous solution of SURFACTANTS on the adsorption process to understand the adsorption and self-assembly mechanism of surfactant mixtures on the graphene surface and also to better optimize the graphene dispersion process. The simulation results suggested the improved stability of these systems by adding an electrolyte to the aqueous solution of the SURFACTANTS. The screening effect of electrolyte ions on the electrostatic repulsion between groups of charged heads of SURFACTANTS has led to a denser accumulation of SURFACTANTS on graphene and more favorable interactions between them. Increasing temperature, however, reduced the system's stability by desorbing the MIXED SURFACTANTS from the graphene surface. Comparing the surfactant molecules and graphene in terms of energy levels of Lennard-Jones interactions with and without alcohol also showed increased interactions in the absence of alcohol, which helps improve the system stability.