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Information × Registration Number 0309U007008, 0107U000661 , R & D reports Title Chemical process in solution containing selfassocoated molecular assembles, supramolecules and complicated nanosized particles popup.stage_title Кіслотність,сольватохромія та сольватація індикаторів в рочнинах дендримерів різної будови та "молекулярних щітках" Head Mchedlov- Petrosyan Nikolai, Registration Date 20-01-2009 Organization Kharkov national university named after V.N. Karazin popup.description2 The objects of research are reaction media of new type: solutions of polyelectrolyte brushes, micellar solutions, microemulsions, suspensions of liposomes, as well as water-organic mixtures, nonaqueous solutions, and indicator dyes of various nature and organic salts. The aim of the study The aim of the study was the determination of quantitative regularities of the influence of the reaction medium, in particular, of molecular assemblies, polyelectrolyte brushes, nonaqueous solvents, on the character of ionic processes, spectral and thermodynamic properties pf organic reagents, and to develop approaches for predicting this influence. Methods of research: spectrophotometry, potentiometry, conductance, solubility. The behavior of acid-base indicators in suspensions of anionic and cationic polyelectrolyte brushes as well as in the presence of the latter's CTAB-complexes was examined. The differentiating action provided by these systems in respect to indicator protolytic equilibria is less expressed than in the case of micelles. First of all it is due to high hydration degree of brush polelectrolyte layer, and secondly, it owes the grafting density of polyelectrolyte chains. The interfacial polarity in thirty-seven colloidal systems was determined using Reichardt's indicator. The influence of micellar microenvironment on ionization constants of a bi-functional indicator dye was studied. The limited character of the classical electrostatic model of the equilibrium in the pseudophase was demonstrated. The quantitative characterization of acid-base equilibria of a large number of dyes, located in molecular assemblies, gives new examples of the differentiating influence of microdroplets, liposomes, and micellar pseudophases. The main reason for such influence is the highly nonuniform nature of the interface. The indices of the so-called apparent ionization constants, , of some fluorescein derivatives were determined in micellar solutions of colloidal surfactants and direct microemulsions by means of spectrophotometry; the pH values were checked in cells with liquid junction by glass electrodes. The interfacial electrostatic potential of ionic micelles was evaluated. The solubility of cetyltrimethylammonium perchlorate (CTAP) in propan-2-ol and its mixtures with water was determined by the isothermal saturation method over the whole composition range at 278,15-308,15 K. The solubility products and total standard Gibbs energies of transfer of the n-С16Н33(СН3)3N+ and ClO4? ions were calculated. The solubility of CTAP in the mixed solvent specified was substantially influenced by solvophilic effects and the heterosolvation of ions caused by them. Acetone with small (e.g., 5 mol. %) additive of ДМСО is considered as a media for acid-base reactions. The values of picric acid in acetone containing 0.5 to 6 mol. % DMSO are treated in terms of proton solvation with two DMSO molecules. The equilibrium of proton exchange, H(AC)2+ + 2 ДМСО H(ДМСО)2+ + 2 AC. The study of behavior of methyl orange in the presence of organic phaseis also made and the distribution constants of various forms of this azodye between water media and the drops of microemulsion were estimated and object of research of this work is a chemical equilibrium of process of dissociation of organic acids in organic solvents. The equilibrium of dissociation of picric acid is as an example considered in n-butanole. The purpose of work is a calculation of constant of dissociation of picric acid in n-butanole at the temperature of 25°С for further treatment of results with the purpose of creation of scale of acidity in n-butanol. The behavior of tetra-n-butylammonium picrate, TBAPic, in acetone-n-hexane solvent system, with the relative permittivity changing gradually from =15,22 to =5,10, was studied at 25,0 C. The association constants (TBA+ + Pic- ion pair, ) and the limiting molar conductivities were determined using the Lee-Wheaton equation. Hojo's method, modified to some extent by us, was used to fit the phoreograms by taking into consideration symmetrical ion triplets, with equilibrium constants . Association of Eu(DPM)3 ions with betain dye ET(30) in acetone has been investigated by spectrophotometric method. Basing on spectral absorption bands of betain dye at addition of different values of Eu(DPM)3 by method of regression analysis were calculated a association constant. A good coincedence between experimental and semiempirical constants values confirmed a accuracy of this mathematical calculation method. 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