Results 161 to 170 of about 19,763 (236)

Mathematical modeling of separation of microamounts of strontium from yttrium in the two-phase water-nitrobenzene extraction system

Journal of Radioanalytical and Nuclear Chemistry, 2007
A rapid extraction separation of microamounts of Sr2+ from Y3+ using HCl, benzo-15-crown-5 (B15C5) and hydrogen dicarbollylcobaltate (H+B-) in the two-phase water-nitrobenzene system was developed. The reached separation factor α(Sr/Y) was higher than 105.
Emanuel Makrlík, Petr Vaňura
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Contribution to the Thermodynamics of Complexes of Alkali Metal Cations with Benzo-18-Crown-6 in the Water–Nitrobenzene Extraction System

Zeitschrift für Physikalische Chemie, 2006
From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium M+(aq) + NaL+(nb) ⇔ ML+(nb) + Na+(aq) taking place in the two–phase water–nitrobenzene system (M+ = Li+, K+, Rb+, Cs+; L = benzo-18-crown-6; aq = aqueous phase, nb = nitrobenzene phase) were evaluated.
Emanuel Makrlík, Petr Vaňura
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Extraction separation of barium from strontium in a two-phase water-nitrobenzene system

Journal of Radioanalytical and Nuclear Chemistry Letters, 1985
A rapid extraction separation of Ba2+ from Sr2+ with a nitrobenzene solution of sodium dicarbollylcobaltate /NaDCC/ in the presence of polyethylene glycol having mean relative molecular weight 400 /PEG 400/ and tetrasodium salt of trans-cyclohexane-1,2-diamine-N,N,N′,N′-tetraacetic acid /Na4L/ was developed.
Emanuel Makrlík, Petr Vaňura
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Free energies of transfer of 1 : 1 electrolytes from water to nitrobenzene. Partition of ions in the water + nitrobenzene system

Journal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 1983
Free energies of solution of 1 : 1 electrolytes in nitrobenzen have been obtained from solubility measurements. Free energies of transfer for these electrolytes from water to nitrobenzene were obtained by combining their free energies of solution in the organic solvent and in water.
Angela F. Danil de Namor, Tony Hill, Elizabeth Sigstad   +2 more
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Transfer of cesium ion from the aqueous phase into the mixed organic phase of a two-phase water/nitrobenzene-carbon tetrachloride extraction system

Journal of Radioanalytical and Nuclear Chemistry Articles, 1991
Standard Gibbs energies of transfer of cesium ion from water to nitrobenzene and nitrobenzene-carbon tetrachloride mixture have been evaluated from electrochemical measurements. From the results the conclusion can be drawn that with increasing dielectric permitivity of organic mixed solvents the value of the Gibbs transfer energy of Cs+ ion decreases.
Alena Paulenová, V. Švec, R. Kopunec
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Thermodynamics of transfer of some univalent ions from the aqueous phase into the nitrobenzene phase of a two-phase water-nitrobenzene extraction system

Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 1983
Abstract The transfer of Cs + and TMA + (tetramethylammonium) cations across the water-nitrobenzene interface was studied by the cyclic voltammetry method in the temperature range 5–65°C. With the use of simple thermodynamic cycles, the changes of the enthalpy and entropy of individual transfer of several univalent cations (Li + , Na + , H + , K + ,
Emanuel Makrlík
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Voltammetric study of complexing sodium cation with dibenzo-18-crown-6 in nitrobenzene phase of two-phase water-nitrobenzene extraction system

Electrochimica Acta, 1983
Abstract The facilitated transfer of the Na + cation through the water (w)/nitrobenzene (nb) interface affected by dibenzo-18-crown-6 dissolved in the organic phase was studied by the cyclic voltammetry in the temperature range of 5–65°C. The transfer was found to be a very fast process at each studied temperature (5, 20, 35, 50, and 65°C); the ...
Emanuel Makrlík, Le Quoc Hung, A. Hofmanová   +2 more
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Contribution to the thermodynamics of bromophenol blue in the two-phase water-nitrobenzene extraction system

Collection of Czechoslovak Chemical Communications, 1990
General relations among thermodynamic parameters characterizing dissociation equilibria with species H2A, HA- and A2- (H2A is a symbol for an electroneutral undissociated acid) in a two-phase extraction system have been derived. From the extraction measurements, the equilibrium distribution constant of electroneutral bromophenol blue between the ...
Emanuel Makrlík
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Thermodynamic parameters characterizing complexes of alkali metal cations with dibenzo-24-crown-8 in the water—nitrobenzene extraction system

Colloids and Surfaces, 1992
Abstract By using known thermodynamic parameters, the Briggs logarithms of the individual extraction constants for the ML + complex cations (M + = Na + , K + , Rb + , Cs + ; L = dibenzo-24-crown-8) in the water—nitrobenzene extraction system at 25 C have been evaluated. It has been found that these constants increase in the order Na + + + + ,
Emanuel Makrlík
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Study of supporting electrolyte adsorption in the water/nitrobenzene partition system

Journal of Electroanalytical Chemistry and Interfacial Electrochemistry, 1991
Wojciech S. Wawrzyńczak, Iwona Paleska, Zbigniew A. Figaszewski   +2 more
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