Search results for "Surfactant"
showing 7 items of 397 documents
Do electrospray mass spectra of surfactants mirror their aggregation state in solution?
2011
One important feature in the gas phase chemistry of surfactants is to ascertain whether their aggregates produced by electrospray ionization reflect those formed in the starting solution. With this aim, we have performed ESI-MS, ESI-MS/MS and ER-MS spectra of bis(2-ethylhexyl)sulfosuccinate (AOTNa) solutions in different solvents, i.e. water, water/methanol, methanol and n-hexane. The results clearly indicate that, notwithstanding the strongly different aggregation state in solution (direct micelles in water and in water/methanol, molecular dispersion in methanol and reverse micelles in n-hexane) and marked effects of the solvent polarity on the total ionic current, the surfactant aggregate…
Administración de Surfactante mediante técnica mínimamente invasiva en recién nacidos pretérmino: evaluación de la seguridad y la eficacia
2021
La terapia con surfactante forma parte de la práctica habitual en el manejo del distrés respiratorio en el recién nacido. Su administración ha sido tradicionalmente mediante intubación endotraqueal. Con el fin de minimizar el tiempo de intubación y ventilación mecánica se diseñó la estrategia INSURE (intubación, administración de surfactante y extubación), disminuyendo la posible exposición a la ventilación mecánica. En los últimos años se han investigado nuevas técnicas de administración de surfactante menos invasivas con el objetivo de minimizar los efectos de la intubación traqueal y evitar la aplicación de la ventilación mecánica. El método SONSURE consiste en la administración de surfa…
Demo 61. Tensión superficial. Ley de Tate
2013
Objetivo: Observar la diferencia de tensión superficial entre el agua y el alcohol. Comprobar el efecto de un surfactante como reductor de la tensión superficial.
Review: Mass spectrometry of surfactant aggregates
2011
In contrast with the enormous amount of literature produced during many decades in the field of surfactant aggregation in liquid, liquid crystalline and solid phases, only a few investigations concerning surfactant self-assembling in the gas phase as charged aggregates have been carried out until now. This lack of interest is disappointing in view of the remarkable theoretical and practical importance of the inherent knowledge. The absence of surfactant–solvent interactions makes it easier to study the role of surfactant–surfactant forces in determining their peculiar self-assembling features as well as the ability of these assemblies to incorporate selected solubilizate molecules. Thus, th…
A route to simple nonionic surfactants
2016
AbstractA method for the synthesis of nonionic surfactants – N-alkyl-O-(2-hydroxyethyl) carbamates is proposed by acylation of fatty amines with ethylene carbonate without any solvent or catalyst. The surface tension of the prepared surfactants was measured, toxicity and biodegradability were determined for the surfactant with n-dodecyl as a hydrophobic group and N-monosubstituted amide and hydroxyl groups for their hydrophilic part.
Clay/Non-Ionic Surfactant Hybrid Nanocomposites
2020
This chapter gives an overview of the structural and chemical physical properties of nanocomposites formed by clay minerals and surfactants, which represent a class of materials with promising features for applications in different industrial, biomedical, and environmental applications. Due to their non-toxicity and biocompatibility, a great deal of attention is nowadays devoted to the study of non-ionic surfactants. Among them, block copolymers represent a combination of the properties of common amphiphilic molecules and long polymer chains. These macromolecules can form a great variety of supra-molecular structures generated from self-organization phenomena in aqueous media. Nanostructure…