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Information × Registration Number 0216U001285, 0112U008338 , R & D reports Title Physical and chemical procesy in the zhidkofaznykh environments of different types, containing nanorazmernye particles and supramolekulyarnye bands popup.stage_title Head Mchedlov-Petrosyn N., Registration Date 03-02-2016 Organization Kharkov National University named after V.N. Karazin popup.description2 Objects of research: physic-chemical processes in liquid media, which contain supramolecular assemblies of versatile calixarenes, dendrimers, cyclodextrines, amphifilic reagents of surfactant type, including direct and reversed microemulsions, heteronanoparticles (silica species covered by layers of cationic surfactants, spherical polymeric polyelectrolytic brushes), as well as fullerenes in form of both molecules and aggregates. The aim of the research: to reveal the main regularities of the influence of supramolecular systems and nanosized particles on the protolytic and related equilibria of different types of reagents in liquid media. To consider the possibility of existence of thermodynamically stable solutions of fullerenes. To develop new approaches to utilization of reaction kinetics and light emission for examining organized media. To propose methods of governing the equilibrium and kinetics in these systems, which will allow rationalize the creation of new composites, including sensors and sorbents, and optimize the conditions of their application. Methods of research: spectrophotometry, spectrofluorometry, potentiometry, conductivity, dynamic light scattering, transmission electron microscopy, kinetic methods. The scheme of tautomeric transformations of fluorescein was applied to the four-protic acids aminofluoresceins. The presence of additional tautomers, caused by the aminogroup in the phthalic moiety, was revealed. The influence of the calixarenes with various length of alkyl chains on the fluorescence intensity and rate of the reactions of dyes with the hydroxide ion allows proposing a set of indicative processes for distinguishing between the common spherical surfactant micelles and micelle-like aggregates. Meanwhile, the state of acid-base equilibria and the absorption spectra in the abovementioned systems are similar. The kinetics of nucleophilic attack in organized solutions based on colloidal surfactants and supramolecular systems was studied. The constants of reaction rates between triphenylmethane dyes and hydroxide ion in micellar solutions of triphenylmethane dyes were determined by the spectrophotometric method. The main regularities of the influence of surfactants on the reaction rates were revealed. Owing to the hydrophobic effects and electrostatic interactions, the cationic triphenylmethane dyes crystal violet, malachite green, and brilliant green are binded by the micelles of all types of surfactants. In the case of cationic surfactants, the effect of concentration of ОН- in Stern layer leads to additional acceleration of reactions as compared with nonionic surfactants. In solutions of anionic surfactants, the association of cationic dyes with surface-active anions takes place. This leads to the drop of the rate constant even in the pre-micellar range. Product Description popup.authors Водолазька Н. Гайденко Н. Гога С. Камнева Н. Лагута А. Мчедлов-Петросян М Пальваль І. Рощина К. Чейпиш Т. Шеховцов С. popup.nrat_date 2020-04-02 Close