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- Author or Editor: D. Zivkovic x
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Abstract
The results of calorimetric investigations in the section Pb-Bix-Mgy-Sbz (mole ratio Bi:Mg:Sb=8:1:1) of the system Pb-Bi-Mg-Sb with Oelsen's method are presented. The constructed space diagram and enthalpy isotherm diagram were used to determine integral mixing enthalpies for the investigated section in the temperature interval 450–1100 K.
Abstract
This paper presents the results of simultaneous DTA-TG-DTG and DSC studies on the thermal decomposition of Cu(NO3)23H2O, Co(NO3)26H2O and Ni(NO3)26H2O in an air atmosphere. The mechanism and enthalpies of the investigated processes were determined, as well as the kinetic parameters of the processes run under non-isothermal conditions by means of Kissinger's method. The dependence of the activation energy on the ionic radius of the cations building up the crystal lattices of the investigated compounds was also studied.
Abstract
R-function method for predicting the ternary thermodynamic properties from its binary ones was applied to the ternary system Pb−Bi−Mg. Activities, activity coefficients, partial and integral molar quantities for Pb, Bi and Mg for the quasibinary sections Pb-X (X=B, C, D, E, F) in the investigated ternary system Pb−Bi−Mg calculated by means ofR-function method are given in this paper. Also, it was determined that results obtained byR-function method reach a good agreement with the experimental results obtained by Oelsen calorimetry.
Abstract
In this paper, Ga-GeSb0.855 section in the ternary system Ga–Ge–Sb was studied using thermodynamic predicting methods by Muggianu and Toop, while characterization of the chosen alloys was done by DTA, X-ray and SEM-EDX method.
Abstract
Thermodynamic investigations of Ga-GeSb0.855 section in the ternary system Ga-Ge-Sb, which is of a practical importance in electric-industry, are presented in this paper. Results of a comparative thermodynamic analysis at 1273 K obtained by Oelsen calorimetry and predicting methods - general solution model and Hajra's method are also given.
Abstract
Results of the comparative thermodynamic analysis of the Bi-Ga0.1Sb0.9 section in theBi-Ga-Sb system are given in this paper. Experimental calorimetric investigations were done according to Oelsen's method, while for the thermodynamic prediction Chou's general solution model was applied. Activities, activity coefficients, partial molar quantities for bismuth and integral molar quantities were obtained at a temperature of 1073 K. Based on obtained cooling curves, DTA and SEM results for the investigated samples, phase diagram of the investigated section is constructed and presented in this paper, too.
Abstract
Results of the experimental thermodynamic investigations of the system Bi-Au2Bi obtained by using Oelsen calorimetry are presented in this paper. Activities, activity coefficients and partial molar quantities for bismuth in the temperature interval 600-1000 K are determined. Based on the values of the thermodynamic parameters, negative deviation from Raoult law was obtained for the investigated system. Also, bismuth activities and activity coefficients dependence on composition and temperature is calculated by the nonlinear programming using gradient method.
Abstract
Results of the comparative thermodynamic analysis of the binary system Bi−Sb obtained by DTA measurements and predicting are presented in this paper. Activities, activity coefficients, partial and integral molar quantities for Bi and Sb at temperatures 973, 1073 and 1173 K in the investigated binary system Bi−Sb determined by DTA measurements and thermodynamic predicting are given. An excellent agreement between the experimental and predicted results is reached. Also, a phase diagram of the investigated system Bi−Sb obtained by DTA shows good agreement with literature and it can be concluded that DTA could be satisfactorily used for quantitative thermodynamic analysis of any binary system containing equilibrium between solid and liquid solutions. It was also determined that conclusion about linear dependence ofgKs constant for binary eutectic systems and systems with phase transformation is valid for binary system containing equilibrium between solid and liquid solutions too.
