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Showing 1 to 20 of 66 for “"surfactant concentration"”.
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Investigation of the effects of surfactant concentration on the boiling curve of water
… study the effects of two homologous series of surfactants (trimethylammonium bromide (TAB) and methylglucamine (MEGA)) on the boiling curve of water were explored. Heat transfer vs. temperature plots were obtained for five surfactants for various concentrations under the cricical micelle …
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Ultrasonically initiated free radical catalyzed emulsion polymerization of methyl methacrylate
… temperature using sodium lauryl sulfate as the surfactant.</p> <p>The source of the free radical for the initiation process was found to come from the degradation of the sodium lauryl sulfate presumably in aqueous phase. The weight average molecular weight (Mw) of the poly (methyl methacrylate) …
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Computational methods for two-phase flow with soluble surfactant
… zero Reynold's number or Stokes flow limit. A surfactant that is present on the interface is also soluble in the exterior fluid, and the drop is deformed by an imposed linear flow. The geometry is two-dimensional and Cartesian. The dissolved surfactant is considered in the physically realistic …
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Influences of surfactant on the breakup of a fluid jet in viscous surrounding
The effect of insoluble surfactant on the breakup of a fluid jet surrounded by another viscous fluid at low Reynolds number is studied both theoretically and experimentally. Equations governing the evolution of the interface and surfactant concentration are derived using a long wavelength …
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Hydrophobic Forces in Free Thin Films of Water in the Presence and Absence of Surfactants
… The steric force also increased with electrolyte concentration, possibly due to a decrease in the mobility of the tails of the asphaltenes on the surface. The kinetics of coalescence of bitumen droplets was studied by measuring the induction time. There was a general agreement between the force …
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High yield production of inorganic graphene-like materials (MoS₂, WS₂, BN) through liquid exfoliation testing key parameters
… number of parameters that can yield the highest concentration of layered quantities of MoS₂, WS₂, and BN. The key parameters optmized were material concentration, surfactant concentration, sonication method and duration, and centrifuge speed. Therefore, different concentrations of the three …
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An x-ray scattering study of surfactant water mixtures
… nematic and lamellr mesophases in concentrated surfactant / water mixtures is a well documented phenomenon. This work examines the structure and order of the mesophases exhibited by two sample systems, caesium pentadecafluorooctanoa-te (CsPFO) / heavy water, and decylammonium chloride / ammonium …
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Influence of surface tension and concentration of a non-ionic surfactant on the barrier effectiveness of a microporous polypropylene fabric for pesticide protective clothing
This research evaluated the influence of concentration and surface tension (γ) of aqueous solutions of a non-ionic surfactant on the barrier effectiveness of a fabric containing microporous polypropylene (PP) film that may be used in pesticide protective clothing (PPC). Aqueous solutions of Triton® …
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Synthesis, Characterization, Processing and Physical Behavior of Melt-Processible Acrylonitrile Co- and Terpolymers for Carbon Fibers: Effect of Synthetic Variables on Copolymer Synthesis
… effects of chain transfer agent, initiator, and surfactant concentration on the polymer properties were studied.
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Surface Forces in Foam Films
… to as hydrophobic force) exists at very low surfactant concentrations, and that it decreases with increasing surfactant and/or electrolyte concentrations. In contrast, pH changes have only minor effects on the hydrophobic force. The changes in the hydrophobic force observed at low surfactant …
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Formulation development of a novel antivirulence compound for enhanced pharmacokinetic properties
… 5 minutes under in-vitro sink environment. The concentration of surfactants in antisolvent and the ultrasonic cavitation intensity are regarded as two of the most important parameters affecting particle size and morphology. Small plate-like particles were produced with low surfactant …
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Thin liquid films with nanoparticles and rod-like ions as models for nanofluidics
… of the channels can be adjusted easily by the concentration of electrolyte in the film forming solution. This way, channel dimensions from 5 – 100 nm are possible, a high flexibility for an experimental system. TLFs have liquid IFs of different charge and properties and they offer the …
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Electrical conductivity of polyaphrons (biliquid foams)
… of the nature of oil phase and aqueous phase surfactant, oil phase surfactant concentration, the nature of oil phase components, and the type of electrolyte added to aqueous phase to enhance electrical signal. Graphs of relative electrical conductivity ratios (conductivity of polyaphron to …
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Study of Surface Tension, Natural Evaporation, and Subcooled Boiling Evaporation of Aqueous Surfactant Solutions
<p>The relation between surface tension and surfactant concentration and its effect on solution evaporation under natural convection and subcooled pool boiling is examined through experimental methods. Aqueous solutions of sodium lauryl sulfate (SLS), ECOSURFTM EH-14, and ECOSURFTM SA-9 are used in …
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Microfluidics enhanced synthesis of micellar nanostructures
Surfactant molecules can self-assemble into various morphologies under proper combinations of surfactant concentration, temperature, and flow conditions. In equilibrium, micelles can transition from entangled to branched structures with increasing ionic strength and temperature. Under flow …
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Synthesis of polymeric nanocomposites in supercritical carbon dioxide
… (PMMA)/silica nanocomposites with different surfactant and filler concentrations synthesized through in-situ polymerization in supercritical carbon dioxide were investigated. In addition, ferromagnetic nano-particles were synthesized and functionalized for the preparation of nanocomposites. …
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Mechanisms of Solubilization and Mass Transfer in Oleic Acid/aqueous Surfactant Systems
… to the formation of an oleic acid/aqueous surfactant liquid crystalline phase at the liquid/liquid two phase boundary. This interfacial phase was capable of being sheared and dissipated under flow conditions. Steady state solute fluxes under non-flow conditions were consistent with the …
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Characterization of water-based liquid scintillator response to gammas and neutrons at varying scintillator-surfactant concentrations
… for the bulk scintillator, dissolved in Triton-X surfactant to fix the issue polar/non-polar solubility. A scintillator mixture comprised of 3.000 grams PPO, 0.075 grams POPOP, 240.0 grams of Triton-X diluted in deionized water is identified to produce optimal light yield. The relationship of …
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Microemulsion and macroemulsion behaviour of systems containing oil, water and nonionic surfactant
… (W/O) systems stabilised by pure nonionic surfactants of the poly-oxyethylene alkyl ether (CnEm) type. Initially however, a brief account is presented of the behaviour of W/O microemulsions stabilised by commercial nonionic surfactants of the type used in foods.A detailed study of the …
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Surfactants in nonpolar oils: agents of electric charging and nanogel templates
… but can do so in the presence of certain surfactant additives. Surfactant-mediated charging in nonpolar oils has long been exploited industrially, but the underlying charging mechanisms are far from understood. The present work seeks clarification by comparing the effect of ionic and …
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