Aggregation in a mixture of cetyltrimethylammonium bromide and polyoxyethylene 600 monolaurate solutions

Micellization in the cetyltrimethylammonium bromide (CTAB)-polyoxyethylene 600 monolaurate (PL)-chloroform system is studied with dielcometric titration, NMR self-diffusion (2D DOSY), 13C NMR spectroscopy, and light scattering methods. The formation of mixed aggregates of surfactants is established. It is shown that CTAB and PL polar moieties interact in the inverse micelle core in the vicinity of PL carbonyl group. © Pleiadas Publishing, Inc., 2006

Novel self-assembling systems based on amphiphilic phosphonium salt and polyethylene glycol. Kinetic arguments for synergetic aggregation behavior

Structural behavior and catalytic activity toward basic hydrolysis of O-alkyl-O-p-nitrophenyl chloromethyl phosphonates (alkyl=ethyl (S1) and hexyl (S2)) of mixed cetyl triphenyl phosphonium bromide (TPPB)-polyethylene glycol (PEG) systems are studied. The interdependence of aggregates and substrates is revealed from symbate changes in their self-diffusion coefficients determined by NMR FT-PGSE method. Much lower zeta-potentials of mixed systems as compared to single TPPB micelles are found, although the counterion binding of aggregates decreases with the addition of PEG. A 1.5-2-fold increase in the reactivity of phosphonates is shown to occur in mixed TPPB-PEG systems versus single surfactant micelles. In addition, a polymer induced shift of the onset of the rate acceleration toward the lower concentrations is observed. These findings provide strong evidences for synergetic solution behavior in the TPPB-PEG systems. The quantitative treatment of kinetic data in terms of pseudophase model sheds light on the factors of catalytic action. In the case of hydrolysis of S1, the more favorable microenvironment is responsible for the higher catalytic effect of mixed systems as compared to single TPPB micelles, while the factor of concentration decreases. The opposite trend is observed for hydrolysis of phosphonate S2, for which an increase in the micellar rate effect with the PEG addition is mainly contributed by the growth of the factor of concentration. © 2012 Elsevier B.V

Self-assembling systems based on amphiphilic alkyltriphenylphosphonium bromides: Elucidation of the role of head group

A systematic study of the aggregation behavior of alkyltriphenylphosphonium bromides (TPPB-n; n=8, 10, 12, 14, 16, 18; here n is the number of carbon atoms in alkyl groups) in aqueous solutions has been carried out and compared with trimethyl ammonium bromides (TMAB-n). Critical micelle concentrations (cmcs) of TPPB-n and TMAB-n decrease with the number of carbon atoms with the slope parameter of ca.0.3. The low cmcs and effective solubilization power toward Orange OT indicate high micellization capacity of phosphonium surfactants. The low counterion binding parameter β is revealed for TPPB-10 and TPPB-12, while high counterion binding of ≥80% is observed for high TPPB-n homologs. Values of the surface potential ψ calculated on the basis of pK a shifts of p-nitrophenols is similar for both series and monotonously increase with alkyl chain length. Several points indicate non-monotonic changes within TPPB-n series. There are peculiarities of the tensiometry and solubilization plots for high homologs and above mentioned increases in counterion binding on transiting from low to high molecular weight surfactants. Differences in aggregation behavior between TPPB and TMAB series and between low and high homologs can be due to the specific structural character of the TPP + cation, which is supported by X-ray data. © 2011 Elsevier Inc

Some approaches to translation of professional terms abbreviation in materials science

The dynamic growth of international collaboration in the scientific and professional spheres leads to a wave-like increase in the volume of translations of professional and scientific texts and determines the relevance of the problem under study. Translators have problems translating abbreviations of professional terms. This paper analyzes the ways of translating English abbreviations in the field of materials science. As research methods, we used, among other things, the analysis of methods of translating English abbreviations into Russian, the study of articles in the field of materials science, the collection of data on abbreviations of professional terms and the comparison of the ways of translation of abbreviations of professional terms in the texts of materials science. The article reveals the features of the ways of translating abbreviations of professional terms in materials science texts. The main results of the research work are the identification of problems of translation of English abbreviations that the translator faces in the field of materials science, and the determination of the use frequency of one or another translation method. The materials of the article can be useful for researchers in this field, physics students and translators of scientific and technical texts

Aggregation in a mixture of cetyltrimethylammonium bromide and polyoxyethylene 600 monolaurate solutions

Micellization in the cetyltrimethylammonium bromide (CTAB)-polyoxyethylene 600 monolaurate (PL)-chloroform system is studied with dielcometric titration, NMR self-diffusion (2D DOSY), 13C NMR spectroscopy, and light scattering methods. The formation of mixed aggregates of surfactants is established. It is shown that CTAB and PL polar moieties interact in the inverse micelle core in the vicinity of PL carbonyl group. © Pleiadas Publishing, Inc., 2006

The role of composition and structure of vanadium-doped nanosized titanium(iv) oxides (anatase and η-phase) in the realization of photocatalytic, adsorption and bactericidal properties

Samples containing vanadium-doped nanosized titanium(iv) oxides with anatase and η-phase structures were prepared by a modified sulfate process, and samples with vanadium-doped η-phase were prepared for the first time. The bulk and the surface of the samples were characterized by a lot of methods, including X-ray diffraction, diffuse reflectance spectroscopy, X-ray absorption spectroscopy (EXAFS/XANES), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The photocatalytic activity (PCA) of the samples was studied in the reaction of photodegradation of the cationic dye rhodamine 6G (in the visible region) and the systemic triazole fungicide difenoconazole (in the UV and visible regions). The PCA was found to be influenced by the phase composition of the samples, the composition of their surface, and nanosized titanium(iv) oxide modifications. Vanadium-doped samples with η-phase containing different ions (Ti3+, Ti4+, V4+, and V5+) and reactive OH groups on the nanoparticle surface exhibited the highest PCA. The samples were shown to have a higher adsorption capacity (AC) for the extraction of As(v) (the highest AC in the presence of vanadium-doped anatase and η-phase) and P(v) (the highest AC in the presence of undoped anatase and η-phase) anions from aqueous systems. The adsorption capacity correlates with the amount of reactive OH groups on the nanoparticle surface and does not depend on the modification of the adsorbent. Only vanadium-doped anatase containing the largest fraction of an amorphous component and the largest amount of SO4 2- groups on its nanoparticle surface exhibits antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Bacillus anthracoides. Vanadium doped anatase and η-phase can be used to purify aquatic environments of harmful organic pollutants and a wide range of anions. © 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique

Novel self-assembling systems based on amphiphilic phosphonium salt and polyethylene glycol. Kinetic arguments for synergetic aggregation behavior

Structural behavior and catalytic activity toward basic hydrolysis of O-alkyl-O-p-nitrophenyl chloromethyl phosphonates (alkyl=ethyl (S1) and hexyl (S2)) of mixed cetyl triphenyl phosphonium bromide (TPPB)-polyethylene glycol (PEG) systems are studied. The interdependence of aggregates and substrates is revealed from symbate changes in their self-diffusion coefficients determined by NMR FT-PGSE method. Much lower zeta-potentials of mixed systems as compared to single TPPB micelles are found, although the counterion binding of aggregates decreases with the addition of PEG. A 1.5-2-fold increase in the reactivity of phosphonates is shown to occur in mixed TPPB-PEG systems versus single surfactant micelles. In addition, a polymer induced shift of the onset of the rate acceleration toward the lower concentrations is observed. These findings provide strong evidences for synergetic solution behavior in the TPPB-PEG systems. The quantitative treatment of kinetic data in terms of pseudophase model sheds light on the factors of catalytic action. In the case of hydrolysis of S1, the more favorable microenvironment is responsible for the higher catalytic effect of mixed systems as compared to single TPPB micelles, while the factor of concentration decreases. The opposite trend is observed for hydrolysis of phosphonate S2, for which an increase in the micellar rate effect with the PEG addition is mainly contributed by the growth of the factor of concentration. © 2012 Elsevier B.V

Aggregation in a mixture of cetyltrimethylammonium bromide and polyoxyethylene 600 monolaurate solutions

Micellization in the cetyltrimethylammonium bromide (CTAB)-polyoxyethylene 600 monolaurate (PL)-chloroform system is studied with dielcometric titration, NMR self-diffusion (2D DOSY), 13C NMR spectroscopy, and light scattering methods. The formation of mixed aggregates of surfactants is established. It is shown that CTAB and PL polar moieties interact in the inverse micelle core in the vicinity of PL carbonyl group. © Pleiadas Publishing, Inc., 2006

The role of composition and structure of vanadium-doped nanosized titanium(iv) oxides (anatase and η-phase) in the realization of photocatalytic, adsorption and bactericidal properties

Samples containing vanadium-doped nanosized titanium(iv) oxides with anatase and η-phase structures were prepared by a modified sulfate process, and samples with vanadium-doped η-phase were prepared for the first time. The bulk and the surface of the samples were characterized by a lot of methods, including X-ray diffraction, diffuse reflectance spectroscopy, X-ray absorption spectroscopy (EXAFS/XANES), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The photocatalytic activity (PCA) of the samples was studied in the reaction of photodegradation of the cationic dye rhodamine 6G (in the visible region) and the systemic triazole fungicide difenoconazole (in the UV and visible regions). The PCA was found to be influenced by the phase composition of the samples, the composition of their surface, and nanosized titanium(iv) oxide modifications. Vanadium-doped samples with η-phase containing different ions (Ti3+, Ti4+, V4+, and V5+) and reactive OH groups on the nanoparticle surface exhibited the highest PCA. The samples were shown to have a higher adsorption capacity (AC) for the extraction of As(v) (the highest AC in the presence of vanadium-doped anatase and η-phase) and P(v) (the highest AC in the presence of undoped anatase and η-phase) anions from aqueous systems. The adsorption capacity correlates with the amount of reactive OH groups on the nanoparticle surface and does not depend on the modification of the adsorbent. Only vanadium-doped anatase containing the largest fraction of an amorphous component and the largest amount of SO4 2- groups on its nanoparticle surface exhibits antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Bacillus anthracoides. Vanadium doped anatase and η-phase can be used to purify aquatic environments of harmful organic pollutants and a wide range of anions. © 2018 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique

Novel self-assembling systems based on amphiphilic phosphonium salt and polyethylene glycol. Kinetic arguments for synergetic aggregation behavior

Structural behavior and catalytic activity toward basic hydrolysis of O-alkyl-O-p-nitrophenyl chloromethyl phosphonates (alkyl=ethyl (S1) and hexyl (S2)) of mixed cetyl triphenyl phosphonium bromide (TPPB)-polyethylene glycol (PEG) systems are studied. The interdependence of aggregates and substrates is revealed from symbate changes in their self-diffusion coefficients determined by NMR FT-PGSE method. Much lower zeta-potentials of mixed systems as compared to single TPPB micelles are found, although the counterion binding of aggregates decreases with the addition of PEG. A 1.5-2-fold increase in the reactivity of phosphonates is shown to occur in mixed TPPB-PEG systems versus single surfactant micelles. In addition, a polymer induced shift of the onset of the rate acceleration toward the lower concentrations is observed. These findings provide strong evidences for synergetic solution behavior in the TPPB-PEG systems. The quantitative treatment of kinetic data in terms of pseudophase model sheds light on the factors of catalytic action. In the case of hydrolysis of S1, the more favorable microenvironment is responsible for the higher catalytic effect of mixed systems as compared to single TPPB micelles, while the factor of concentration decreases. The opposite trend is observed for hydrolysis of phosphonate S2, for which an increase in the micellar rate effect with the PEG addition is mainly contributed by the growth of the factor of concentration. © 2012 Elsevier B.V