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Information × Registration Number 0306U001557, 0104U000660 , R & D reports Title Acidity, solvation,and assotiation in organized solution,microreactors and nanochemical object popup.stage_title Сольватація та солюбілізація в організованих розчинах Head Mchedlov-Petrosyan Nikolai Otarovich, Registration Date 20-04-2006 Organization Kharkov national university named after V.N. Karazin popup.description2 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, gravimetry. The protolytic equilibria of six hydroxyxanthene dyes in direct (benzene in water) microemulsions, stabilized with 1-pentanol and cetyl-trimethylammonium bromide were studied at bulk ionic strength of 1 mol dm-3. The main regularities of medium effects on protolytic equilibria of the aforesaid dyes were revealed. The equilibria of thiofluorescein and thioeosin were studied in water-ethanol and water-acetone mixtures of varying content. It was demonstrated that the monoanion of thioeosin, contrary to that of thiofluorescein, exists as a structure with dissociated hydroxy group and undissociated carboxylic group. The spectral and acid-base properties of a set of sulfonephthalein dyes were studied in aqueous solutions containing tetraammonium-calix[4]arene. The analysis of the 'apparent' values allowed to conclude that the acid-base and spectral properties of the dyes in the presence of cationic calixarene are similar to those in micellar solutions of colloidal cationic surfactants. The solubility of cetyl-trimethylammonium perchlorate in water - 2-propanol system with molar fraction of the alcohol 0, 0.1, 0.3, 0.5, 0.7, and 1.0 was studied within the temperature range of 278.15-308.15 К. The mean-ionic activity coefficients, , were calculated for saturated solutions. The solubility products, standard thermodynamic characteristics of cetyl-trimethylammonium perchlorate, as well as standard thermodynamic transfer characteristics of the mixture of С16Н33N(СН3)3+ and ClO4? ions from water into the solvents studied were determined. The complexes of rhodamine 200 B were studied in organic solvents of different nature. The vis absorption and emission spectra were obtained. The association constants of dye anion with organic cations were calculated from conductivity data. The influence of small additives of dimethyl sulfoxide and water on electromotive force of cells with liquid junction with quinhydrone electrode were studied in HCl and picrate buffer solution in acetone.The association of solvatochromic Reichardt's betaines with lantanoid-shifting reagent Eu(DPM)3 was studied in deuterochloroform using NMR spectroscopy. It was demonstrated that the association occurs with the phenolate oxygen atom. Relatively small shifts give evidence for formation of solvent-separated adducts, as well as for steric hindrance in substituted betaines. 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