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Information × Registration Number 0308U001468, 0107U000661 , R & D reports Title Chemical process in solution containing selfassocoated molecular assembles, supramolecules and complicated nanosized particles popup.stage_title Пролітичні рівноваги індикаторних барвників в міцелярних розчинах ПАР та розчинах молекул рецепторів-каліксагенів і циклодекстринів Head Mchedlov- Petrosyan Nikolai, Registration Date 05-02-2008 Organization Kharkov national university named after V.N. Karazin popup.description2 The objects of research are reaction media of both new type, i.e., solutions of four cationic poly(propyleneimine) dendrimers and solutions of cationic calix[4]arene, and traditional ones, such as water-organic mixtures, as well as indicator dyes of various nature. The aim of the study was to reveal regularities of the influence of reaction media, in particular, of organized solutions, microreactors, water-organic mixtures, on the protolytic and related equilibria, on spectral and thermodynamic properties of organic reagents, and to develop approaches for prediction of such influence.Methods of research: potentiometry, spectrophotometry, fluorometry, 1H NMR spectroscopy, electrical conduction.Aqueous solutions of four cationic poly(propyleneimine) dendrimers have been examined as media for protolytic transformations of indicator dyes. It was shown that these compounds strongly affected acid-base and tautomeric equilibria of dyes, which manifests itself in alteration of indices of apparent ionization constant , the effects having much in common with those observed in cationic surfactant micellar solutions. The difference between micelles and dendrimers under study is revealed in kinetics peculiarity of some reactions. Data about influence of ionic strength on the acid-base and spectral characteristics of bromophenol blue in solutions of cationic calix[4]arene are received. Effects were compared ones earlier determined in other systems. values of dye are increased with increasing of ionic strength as in micellar solutions of cationic surfactants. The equilibrium constants of association of cations with anions, , and limiting molar conductivities were determined in mixtures of water with propan-2-ol within the temperature range of 278.15 - 318.15 K.Association of Mg2+ and La3+ ions with Reichardt's betain dyе has been investigated by NMR-1H in deuterated (D6)DMSO. Comparisons of chemical shifts of betain protons with addition of metal ions with the same in protonated betain show that interaction between metal ions and dye molecule realized by the acid-base scheme. These results allow infer inadmissible application of the betain acid-base sensors in present of the multicharg metal ions. The results obtained can be recommended for physical chemistry, colloid chemistry, biology and biochemistry, photo- and analytical chemistry, as well as in academic courses of physical and colloid chemistry. Product Description popup.authors popup.nrat_date 2020-04-02 Close