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Information × Registration Number 0305U005261, 0104U000660 , R & D reports Title Acidity, solvation, and assotiation in organized solution, microreactors and nanochemical object popup.stage_title Розробка адекватної моделі протолітичних рівноваг в ультрамікрогетерогенних системах та інших видах організованих розчинів Head Mchedlov-Peyrosjn, Registration Date 22-08-2005 Organization Kharkov national university named after V.N. Karazin popup.description2 The objects of research are reaction media of new type: micellar solutions of surfactants, direct and reverse microemulsions, solutions of cyclodextrins and calixarenes. The aim of the study was to reveal the regularities of the influence of organized solutions and microreactors on the protolytic equilibria and related processes, on spectral and thermodynamic properties pf organic reagents, and to predict such influence. Experimental methods: potentiometry, spectrophotometry, fluorometry. The protolytic equilibria of three hydroxyxanthene dyes, fluorescein, eosin, and erythrosine, were studied in direct microemulsions. The indices of the 'apparent' dissociation constants of fluorescein and 2,7-dichlorofluorescein were determined in reverse microemulsions of water-in-oil type stabilized with Aerosol OT. Eleven betaine indicators were studied in direct microemulsions. It was demonstrated that in these systems at volume fractions of organic phase from 0.25 % to 12 % and ionic strengths from 0.025 to 1.0 mol/liter the pseudophase model works satisfactorily, and application of the 'apparent' constants concept was confirmed. The study of betaines and other reactants proves that the surface of sodium dodecylsulfate micelles and that of corresponding droplets of microemulsions is hydrated much stronger than the surfaces of corresponding pseudophases based on cationic and nonionic surfactants.-1)-phenolate with Na+, Mg2+, and La3+ ions as well as with organic acids in n-butanol and DMSO were determined with the help of Vis spectroscopy. It is revealed that the character of spectral changes depends on the charge and concentration of metal ions as well as on the nature of the solvent.The ionic equilibria of methyl orange were studied in the presence of droplets of microemulsions at constant ionic strength and various volume fractions of organic phase; the 'apparent' dissociation constants and partition constants of acid-base couple of the dye were obtained. The protolytic equilibria of dyes in aqueous solutions of calyx[4]arenes and ?-cyclodextrin were studied and the 'apparent' dissociation constants of indicator dyes were determined in these media by using isspectroscopy. 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