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Showing 1 to 20 of 26 for “"Nonionic surfactants"”.
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Solubilization of volatile organic compounds in edible nonionic surfactants
… of benzene, toluene and TCE in edible nonionic surfactants (Tween 20 and Tween 80 which are mono-fatty acid esters of polyoxyethylene sorbitan) by a modification of the EPICS (Equilibrium Partitioning In Closed Systems) method. Benzene and toluene were used to represent light NAPLS …
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Development of novel methodologies to analyze the adsorption kinetics of nonionic surfactants
… Dynamic Surface Tension (DST) behavior of surfactants, and (ii) design optimal surfactant formulations for applications in which the surfactant adsorption kinetics plays a significant role in determining the effectiveness of the formulation. This thesis deals with modeling the adsorption …
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The structure and kinetics of oil-in-water microemulsions stabilised by nonionic surfactants
… oil-in- water (01W) microemulsions stabilised by nonionic surfactants of the general structure H-(CH2)n(OCH2CH2)m-OH, abbreviated to CnEm. The aims were to attempt to characterise their behaviour in terms of the effect of the different constituents n, m, and alkane oil chain length (x).Initially …
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The Effects of Nonionic Surfactants on the Tris(2,2'-Bipyridl) Ruthenium(Ii)-Tripropylamine Electrochemiluminescence System
… (ECL). In this investigation, the effects of the nonionic surfactants Nonidet P40®, Thesit®, and Triton X-100® were studied. ECL occurs in the Ru(bpy)₃²⁺/TPA system in aqueous solutions with and without surfactants present. An increase in ECL signal (>_8-fold) and duration of the signal (from two …
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Salt effects on micellization, micellar growth, and phase behavior of aqueous solutions of nonionic surfactants
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1993.
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A study of cashew nut shell liquid purification and the synthesis of nonionic surfactants from the component phenols
The major phenolic lipids from natural and technical Cashew Nut-Shell Liquids were isolated by various techniques including precipitation, chemical purification, distillation, phase separation and chromatography. Cardanol, 3-pentadecyl phenol and cardol were polyethoxylated under base catalysed …
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SURFACTANTS DERIVED FROM 2-HYDROXY-4-(METHYLTHIO)BUTYRIC ACID: PHASE BEHAVIOR, INTERFACIAL ACTIVITY, MICROEMULSIONS AND MORE
Surfactants derived from 2-hydroxy-4-(methylthio) butyric acid were investigated. Anionic surfactants derived from this molecule have excellent water solubility, hardness tolerance and surface activity. Nonionic surfactants based on this molecule presented excellent phase behavior in water, high …
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Solubilisation and emulsification of silicone oils in aqueous surfactant systems
… have been investigated with a series of nonionic surfactants and an anionic surfactant (AOT).For nonionic surfactants at oil-water interfaces, the effect of temperature, surfactant structure, electrolyte concentration and PDMS molecular weight on the emulsion phase inversion of …
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Surfactants in nonpolar oils: agents of electric charging and nanogel templates
… by comparing the effect of ionic and nonionic surfactants on the conductivity of nonpolar solutions and the electrophoretically observable surface charge of suspended polymer particles. Both types of surfactant are found to generate mobile ions in solution as well as particle charge; …
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The damaging potential of pesticide formulations on human skin
… damage was achieved using polyoxyethylated nonionic surfactants of the Synperonic NP and PS ranges incorporated in mixtures and as stratum corneum pretreatments. Mechanisms of surfactant damage and protection were assessed. Both anionic surfactants were shown to partition into the stratum …
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Microemulsions formation, stability and their characterisations
… various microemulsion systems stabilised by pure nonionic surfactants and alcohol as well as mixtures of nonionic and anionic surfactants. Phase equilibria and interfacial characteristics of the systems are studied with a view to their potential usefulness for enhanced oil recovery, in which …
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Laboratory experiments on warm fog dissipation.
… the use of hygroscopic materials and ionic surfactants as warm fog dispersants are covered in a brief survey of the literature. The fog chamber, equipment and experimental procedures used in this study are described in detail. Seeding agents utilized during these small-scale fog chamber …
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Studies of Surfactants Effect on Riboflavin Fluorescence and Its Determination in Commercial Food Products and Vitamin Tablets.
… from riboflavin (vitamin B<sub>2</sub>). Surfactants have been known to enhance the intensity of fluorescence of fluorescent compounds. Fluorescence analysis of riboflavin in the presence of various anionic, cationic, and nonionic surfactants was also conducted to determine if they could …
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Kinetics of bubble-particle adhesion in flotation
… by the charge of the polar head of the surfactants when ionic surfactants are used to produce bubbles. However, the magnitude of the zeta-potential is reduced when the surfactants are hydrolyzed. When using nonionic surfactants, the bubbles exhibit isoelectric points (i.e.p) in acidic …
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Study of Surface Tension, Natural Evaporation, and Subcooled Boiling Evaporation of Aqueous Surfactant Solutions
… EH-14 and SA-9 are environmentally-friendly nonionic surfactants.</p> <p>Surfactants, surface active agents, are known to affect evaporation performance of solutions and are studied in relation to water loss prevention and heat dissipation. Surfactants could be useful under drought conditions …
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Microemulsion and macroemulsion behaviour of systems containing oil, water and nonionic surfactant
… to water-in-oil (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 …
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Use of tartrazine dye as a tracer to measure foliar spray retention on turfgrass
… higher spray uniformity and coverage. Adding nonionic surfactants (NIS), organosilicone adjuvants (OSA) and methylated seed oils (MSO) at the median recommended concentration maintained foliar recovery rates at approximately 93% to 90% under both low and high spray volumes. Without adjuvants, …
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A dielectric study of systems exhibiting molecular association.
… alcohol-water systems and micellar solutions of nonionic surfactants. Dielectric relaxation studies have shown that addition of water to an alcohol causes a reduction in the relaxation time of the principal dispersion which for all compositions is Debye-type. The relaxation behaviour has been …
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The effect of spray adjuvants on the phytotoxicity of herbicides
… and flax (Linum usitatissimum L.) to selected nonionic surfactants (Triton XA, Wex and Renex 36) when applied with herbicides. In the greenhouse there were no significant differences in dry matter yield between plants treated with a herbicide plus additional nonionic surfactant in a tank-mix, …
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