Search results for "Surfactant"

CO2 switchable nanoparticles: reversible water/organic-phase exchange of gold nanoparticles by gas bubbling

2013

Gold nanoparticles capped with oleylamine can be effectively transferred from an organic solvent to water in the presence of an acetamidine surfactant by CO2 bubbling and then effectively reverted back to the organic phase by N2 bubbling.

Studies on the UV-photolytic decomposition of some tensides and complexones inhibiting the inverse-voltammetric determination of metal ions

1993

The UV-photolytic decomposition of some tensides and complexones has been investigated using the DPASV peak of indium as an indicator. The results show that UV-irradiation alone can completely decompose these compounds at lower concentrations within a short time. Higher concentrations need an additional oxidising agent.

Surfactant controlled preparation of mesostructured transition-metal oxide compounds

1994

The use of surfactants as templates allows the synthesis of mesostructured transition-metal oxides by a cooperative, interface controlled condensation process.

Formation of a Porous Zirconium Oxo Phosphate with a High Surface Area by a Surfactant-Assisted Synthesis

1996

Surfactant-assisted chromogenic sensing of cyanide in water

2009

Chromogenic cyanide recognition in water was achieved by the use of a hydrophobic dye in micellar containers.

Direct Measurement of Particle−Bubble Interactions in Aqueous Electrolyte:  Dependence on Surfactant

1998

The aim of this study was to determine the influence of surfactant on the particle−bubble interaction. Therefore we constructed an experimental setup with which the interaction between colloidal pa...

Widening the possibilities of liquid chromatography through the use of secondary equilibria with additives and hydrophilic interaction chromatography

2019

La cromatografía líquida (CL) de fase inversa (reversed phase liquid chromatography, RPLC) es el modo de CL más habitual en los laboratorios analíticos, debido a su amplia aplicabilidad, fiabilidad, robustez y sensibilidad. Desafortunadamente, la pérdida de eficacia (especialmente para compuestos básicos, cuyos picos anchos y asimétricos se explican principalmente por la interacción con los grupos silanol residuales aniónicos presentes en el empaquetamiento de la columna), y la retención inadecuada de diversos compuestos (demasiado cortos o excesivos), dificultan una aplicabilidad más universal de este modo cromatográfico. Desde el desarrollo de la técnica, se ha dedicado mucho esfuerzo par…

Orientation and molecular contacts of melatonin confined into AOT and lecithin reversed micellar systems

2008

Abstract The state of increasing amounts of melatonin (MLT) confined in dry AOT or lecithin reversed micelles dispersed in CCl 4 has been investigated by UV–vis and 1 H NMR spectroscopies. The experimental results are consistent with MLT totally entrapped in reversed micelles, as a consequence of specific melatonin/surfactant interaction; the main driving force of the MLT solubilization in the core of reversed micelles is the establishment of H-bonding between the MLT NH groups (both indolic and amidic) and the head group of surfactants. The short contacts deduced from intermolecular NOEs are accounted for by favourable interactions between the surfactant's polar head and the H7–NH–H2 fragm…

Physicochemical investigation of acrylamide solubilization in sodium bis(2-ethylhexyl)sulfosuccinate and lecithin reversed micelles.

2003

The state of acrylamide confined within dry sodium bis(2-ethylhexyl)sulfosuccinate (AOT) and lecithin reversed micelles dispersed in CCl4 has been investigated by FTIR and H-1 NMR spectroscopy. Measurements have been performed at 25 degreesC as a function of the acrylamide-to-surfactant molar ratio (R) at a fixed surfactant concentration (0.1 mol kg(-1)). The analysis of experimental data, corroborated by the results of SAXS measurements, is consistent with the hypothesis that acrylamide is quite uniformly distributed among reversed micelles mainly located in proximity to the surfactant head-group region and that its presence induces significant unidimensional growth of micellar aggregates.…

Structure and optical properties of a monolayer single crystal of a cyanine dye

1992

Abstract Molecularly thin single crystals of a cyanine dye prepared by adsorption at a charged surfactant monolayer are studied by polarized optical spectroscopy and electron diffraction. Both techniques independently show a herringbone arrangement of the dye with the long axes of translationally inequivalent molecules forming an angle of 80°. The dye arranges in a primitive rectangular unit cell (a=21.2 A, b=6.14 A) adjacent to an epitaxially related hexagonal cell of the aliphatic tails of the surfactant.