Cationic Surfactants
Mostrando 1-12 de 36 artigos, teses e dissertações.
-
1. Efficient Encapsulation and Controlled Release of N,N-Diethyl-3-methylbenzamide (DEET) from Oil-in-Water Emulsions Stabilized by Cationic Nanocellulose and Silica Nanoparticles
Oil-in-water emulsions containing N,N-diethyl-3-methylbenzamide (DEET) were developed aiming to extend the sustained release of the active compound, by using two oppositely charged nanomaterials, namely silica nanoparticles (SiNP) and cationic cellulose nanofibrils (CCNF), as stabilizers, and a mixture of food-grade nonionic surfactants to avoid precipitatio
Journal of the Brazilian Chemical Society. Publicado em: 2023
-
2. Organophilic clays and their application in atrazine adsorption
Abstract Atrazine’s adsorptive capabilities make the use of clays practical and effective. Three types of organophilic clays modified by cationic surfactants with the ability of one of these clays to adsorb atrazine in an aqueous medium are discussed in this work. The modification in clays was done with the surfactants cetyltrimethylammonium bromide, cetyl
Cerâmica. Publicado em: 2021-06
-
3. EFFECT OF CYCLOPENTANE HYDRATES ON THE STABILITY OF DODAC AND AOT STRUCTURES
Abstract Hydrates are crystalline structures formed by water and substances with low molar mass molecules. Hydrate formation can occur during oil production when oil, gas and water flow through the same lines in conditions of high pressure and low temperatures. The deposition of hydrate crystals in production lines can severely jeopardize the safety of oper
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
-
4. Synthesis Optimization of MCM-41 for CO2 Adsorption Using Simplex-centroid Design
There is a growing concern on the relationship between anthropogenic carbon dioxide and climate changes. A promising approach is the adsorption technology using mesoporous MCM-41 materials that can be easily synthesized to depict structures adequate to the flow of gas. The aim of this study was to improve the synthesis of MCM-41 using cationic surfactant mix
Mat. Res.. Publicado em: 2015-08
-
5. ASSOCIATION OF BRANCHED POLYETHYLENE IMINE WITH SURFACTANTS IN AQUEOUS SOLUTION
Three polymer-surfactant systems comprised of branched polyethylene imine (PEI) with an anionic surfactant (sodium dodecylsulfate; SDS), a cationic surfactant (tetradecyltrimethylammonium bromide; TTAB), and a zwitterionic surfactant (
N -tetradecyl-N ,N -dimethyl-3-ammonio-1-propanesulfonate; SB3-14) were stQuím. Nova. Publicado em: 2015-07
-
6. Interaction between cationic and conventional nonionic surfactants in the mixed micelle and monolayer formed in aqueous medium
Mixed micellization and surface properties of cationic and nonionic surfactants dimethyl decyl-, tetradecyl- and hexadecyl phosphineoxide mixtures are studied using conductivity and surface tension measurements. The models of Rubingh, Rosen, and Clint, are used to obtain the interaction parameter, minimum area per molecule, mixed micelle composition, free en
Química Nova. Publicado em: 2011
-
7. Surfactants effects on the solid state nitric oxide sensor prepared by Sol-Gel process / Efeito dos sulfactantes sobre o sensor sólido de óxido nítrico preparado pelo processo Sol-Gel
In previous work we present a solid sensor for nitric oxide (NO) prepared by sol-gel method using the trapped complex of Fe 2+ -DETC. In this work, we report the effect of some surfactants (CTAB, cationic, anionic, SDS, Triton-X100 and neutral pluronic F127) on the sensor. The electron paramagnetic resonance (EPR) was used to quantify the number of molecules
Publicado em: 2009
-
8. Interaction of hidrophilic porphyrins and extracellular hemoglobin with biomimetic models of biological membranes / Interação de porfirinas hidrofílicas e de hemoglobina extracelular com modelos biomiméticos de membrana biológica
In the first part of this work interactions of the cationic meso tetrakis (4-N-methilpyridil) porphyrin (TMPyP) and meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS4) in the free base forms with membrane model systems (ionic micelles, mixed micelles and phospholipids vesicles) in aqueous solutions, have been investigated by optical absorption, resonance lig
Publicado em: 2008
-
9. Phase equilibrium and structural characterizarion of systems composed by polyanions and cationic surfactants / Equilibrio de fases e caracterização estrutural de sistemas contendo polianions e surfatantes cationicos
Polieletrólitos associam-se fortemente com surfatantes de carga oposta em meio aquoso, levando a uma separação de fases que resulta em uma fase concentrada, rica em polieletrólito e surfatante, em equilíbrio com uma fase diluída constituída pelos contra-íons. A fase concentrada pode ser constituída de interessantes estruturas supramoleculares advind
Publicado em: 2008
-
10. Sodium dodecyl sulfate-coated alumina and C18 cartridge for the separation and preconcentration of cationic surfactants prior to their quantitation by spectrophotometric method
Um novo método de extração em fase sólida foi desenvolvido para separar e pré-concentrar traços de tensoativos catiônicos, tais como, brometo de dodeciltrimetilamônio (DTAB), brometo de cetiltrimetilamônio (CTAB) e cloreto de cetilpiridínio (CPC). Esse método é baseado na sorção do tensoativo aniônico (AS-), dodecilssulfato de sódio (SDS), so
Journal of the Brazilian Chemical Society. Publicado em: 2008
-
11. A physico-chemical study of the cationic surfactants adsorption on montmorillonite
O objetivo deste trabalho é o estudo da adsorção de brometo de cetiltilmetilamônio (CTA) e de cloreto de cetilpiridínio (CP) em argilas do tipo montorilonita (MMT) ricas em sódio. Um método isotacoforético (ITP) específico foi desenvolvido visando à determinação rápida e simultânea dos surfatantes catiônicos (CS) adsorvidos. A fim de reduzir o
Journal of the Brazilian Chemical Society. Publicado em: 2007-04
-
12. Desenvolvimento de sistemas farmacêuticos emulsionados para veiculação gênica
Terapia gênica, em uma ampla definição, é o tratamento de doenças baseado na transferência de material genético a uma célula, tecido ou órgão com o intuito de curar ou melhorar o estado clínico do paciente. Em sua forma mais simples, a terapia gênica consiste na inserção de genes funcionais em células com genes defeituosos objetivando substitu
Publicado em: 2007