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Showing 1 to 20 of 35 for “"cationic surfactant"”.
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ATR-FTIR Measurements of Cationic Surfactant Exchange Rates at the Solid-Liquid Interface
In many experiments, surfactant adsorption and desorption at solid-liquid interfaces is found to be quite slow, considering that surfactants are small molecules. Attenuated total reflectance Fourier transform infrared spectroscopy was used to study the adsorption, desorption, and exchange of …
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Effects of bacteria polysaccharide and cationic surfactant treatment on the sorption of volatile organic compounds by soil
… organic matter); (2) Soil was modified with cationic surfactant tetrabutyl-ammonium (TBA) and benzyl-diemethyl-sterylammonium (BDMS) respectively. The sorption results on the treated soils were compared to sorption results on the untreated soil. This comparison indicated that there were no …
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Application of Foam for Mobility Control in Enhanced Oil Recovery (EOR) Process
… (EOR) process. The performance of foam and surfactants was evaluated by systematic laboratory study. This includes the screening and evaluation of surfactant formulations for foam EOR process and the investigation of foam for mobility control at reservoir conditions. The adsorption of …
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Magnetic seeding aggregation to enhance the removal efficiency of TiO2 nanoparticles from water
… water. This research presents a method of using cationic surfactant-modified magnetite nanoparticles to enhance removal efficiency of TiO_2 nanoparticles in coagulation and flocculation. Magnetite nanoparticles can be recovered using an organic solvent (such as: cyclohexane) and recycled to …
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Development and application of novel capillary electrophoresis techniques for analysis of DNA fragments and organic pollutants
… capillary, and an improved offline cationic surfactant-assisted solid-phase extraction method were developed for sensitive analysis of herbicides. Besides, simultaneous analysis of 2 groups of acidic pollutants in environmental samples at trace level by a portable CE system with …
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The extraction of Cytochrome C and DsRed2 into reverse micelles
… extracted into reverse micelles with the anionic surfactant AOT. DsRed2, however, is a large tetramer with a p1 of 6.3. It could not be extracted into AOT, but was extracted with the cationic surfactant CTAB, and with a wider error range than cytochrome c. CD data indicate the secondary structure …
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Separation of algae from growth media by CGA flotation
… from growth media was investigated. Anionic, cationic and non-ionic surfactants were used to generate CGAs. Preliminary batch studies showed that two CGA flotation procedures could be successfully used for algae flotation. CGA flotation without pretreatment of algae was only successful using …
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Oligomeric surfactants as novel type of amphiphiles : structure - property relationships and behaviour with additives
The properties of a series of well-defined new surfactant oligomers (dimers to tetramers)were examined. From a molecular point of view, these oligomeric surfactants consist of simple monomeric cationic surfactant fragments coupled via the hydrophilic ammonium chloride head groups by spacer groups …
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Phase Behavior and Structural Transitions in The Mixtures of Cationic Surfactants and Hydrophobic Counterions
… with certain geometry adsorb onto the surface of cationic surfactant micelles and they minimize the repulsion between the headgroups, so the charge density on the surface is reduced. As a result of this, the micelle spontaneously changes its morphology due to a new packing for the head groups. The …
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A technique for harvesting unicellular algae using colloidal gas aphrons
… are each encapsulated in an aqueous shell of surfactant solution. The process is based on the technology of CGA flotation, which involves the formation of algae-bubble complexes (possibly including dissolved inorganic ions) and their subsequent flotation into a stable froth at the surface. At …
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Efficacy of Delmopinol in Preventing the Attachment of Campylobacter jejuni to Chicken, Stainless Steel and High-Density Polyethylene
… Delmopinol hydrochloride (delmopinol) is a cationic surfactant that is effective for treating and preventing gingivitis and periodontitis. This study evaluated the effectiveness of delmopinol for reducing attachment of Campylobacter jejuni to chicken, stainless steel and high-density …
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Foam fractionation and air flotation treatment of a tarsand extraction wastewater
… system, 16 trials were conducted using the cationic surfactant, EHDA-Br. In the second-stage air flotation system, 24 trials were conducted, eight with no polymer addition and 16 with the addition of the low molecular weight, strongly cationic polyelectrolyte, Betz 1195. Ten trials were then …
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Wettability of solid particles in relation to particle-stabilised foams and emulsions
Colloidal particles and surfactants are commonly used, either individually or combined, as stabilisers of emulsions and foams. While the properties of surfactants and particles under a range of conditions and concentrations are relatively well known, there are some areas that require further …
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Transport and Adsorption in Nanoscale Confinement
… be hindered by the electrostatic potential; (2) surfactants will form surface aggregates (a form of micelles) that would not occur without the modified potential. To test the first hypothesis, I studied diffusion of fluorescein sodium salt in the nanoscale water confined between glass surfaces. …
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Preparation and Characterization of Carbohydrate-Functionalized Nanomaterials for Use as Cellular Probes and Targeted Delivery Vehicles
… the surface of gold, silica, nanoparticles, and surfactant vesicles, and (2) the preparation and characterization of carbohydrate-functionalized gold nanospheres and surfactant vesicles. A variety of N-linked glycoconjugates tethered to thiols, siloxanes, and hydrocarbons were synthesized via …
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Therapeutic contact lenses for extended drug delivery
… chain length and concentration of the cationic surfactant. Next, we focus on the use of unsaturated fatty acids in commercial contact lenses to extend the release of three cationic drugs. We demonstrate that lenses loaded with oleic acid can extend drug release kinetics to over 1 month. …
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Positronium formation in organic liquids and studies of micelle, liposome and polymer systems by position annihilation technique
… and structure of the hydrocarbon chain in the cationic and anionic parts of the surfactant molecules. The results are being discussed in terms of existing models. The thermotropic transition, which is an important parameter for all membranes and liposomes, was studied in sonicated …
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Post-harvest spray treatments to reduce Salmonella contamination on cantaloupe surfaces
… Delmopinol hydrochloride (delmopinol) is a cationic surfactant that is effective for treating and preventing gingivitis and periodontitis. The application of delmopinol or CPC to cantaloupe surfaces may be an alternative post harvest technique to reduce the frequency and level of Salmonella …
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On Clay Minerals: Adsorption and Modification
… minerals, and for the action and attrition of surfactant packages employed in enhanced recovery. The surprising adsorption of anionic molecules onto the anionic mica surface from aqueous solution, mediated by specific cations, has been investigated. A key variation in cation behaviour down …
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The Characterization of Cationic Pseudostationary Phases for Electrokinetic Chromatography
… between water and self-assemblies formed from cationic surfactants containing systematic variations in structure. One series of surfactants consisted of N-Alkyl-N-methylpyrrolidinium Ionic Liquid type headgroups. This is the first report of an ionic liquid surfactant used as the …
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