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Abstract  

Experimental results obtained by phase diagram investigation of Pb-In binary system are presented in the paper and compared with literature data. Liquidus and solidus temperatures, as well as cell parameters were determined, and structural analysis of this system was made. Microstructural analysis was done by SEM-EDX, crystallographic analysis was performed by diffractometry, while liquidus and solidus temperatures were determined by DTA. Obtained results show that in investigated system exist three areas: area reach in In, area reach in Pb and separating the intermediate phase (αIn). Experimental results show good agreement with literature.

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Abstract  

Results of the thermodynamic investigations in the Bi–GaSb system are presented in this paper. Thermodynamic characteristics experimentally determined by Oelsen's calorimetric method were compared with values predicted by different thermodynamic predicting methods (general solution model, Kohler, Muggianu, Toop, Hillert) at the temperature of 1073 K. Also, based on the obtained cooling curves and microstructure analysis of the investigated samples by optical microscopy, phase diagram of the Bi–GaSb system was investigated and compared with literature data.

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Abstract  

Results of the comparative thermodynamic analysis of the Pb-BixMgySbz section (x:y:z=8:1:1, in mole ratio) in the Pb-Bi-Mg-Sb system, obtained experimentally by Oelsen calorimetry and predicted by general solution model in the temperature range 600–1100 K, are given in this paper.

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Abstract  

The results of comparative thermodynamic study of GaSb-Sn system are presented in this paper. Calorimetric measurements according to Oelsen's method and EMF measurements with zirconia as solid electrolyte were used for experimental investigation, while Chou's general solution model, Toop, Kohler and Muggianu methods were used for predicting thermodynamic characteristics in this system. Also, phase diagram of this quasibinary system, determined by DTA and optical microscopy, is presented.

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This paper presents qualitative and quantitative comparative results on the simultaneous TG-DTG DTA of five commercial and low-grade bauxites. The methodology of qualitative determination of the basic mineral forms contained in bauxites is currently being established. The weight losses relating to the steps in the TG curve allow determination of the contents of the basic minerals in bauxite. These are recalculated as percentages of Al2O3, SiO2, CaO moisture and total volatiles. The final results are in accordance with the results of classical chemical analyses, and this jusitifies the use of this technique as a quick method for qualitative and quantitative determinations of both commercial and low-grade bauxites.

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Silicothermic reduction process in magnesium production

Thermal analysis and characterization of the slag

Journal of Thermal Analysis and Calorimetry
Authors:
D. Minić
,
D. Manasijević
,
Jelena Ðokić
,
Dragana Živković
, and
Ž. Živković

Abstract  

In this paper there are presented the results of the characterization and thermal analysis of the slag from the magnesium plant ‘Bela Stena’, Serbia. The results of X-ray fluorescence analysis, scanning electron microscopy (SEM), optical microscopy (LOM) and X-ray diffraction (XRD) were used for chemical and mineralogical analysis of the solidified slag samples. Differential thermal analysis (DTA), thermo-gravimetric (TG) analysis and thermal microscopy results were used for determination of characteristic phase transformations. The solidified slag shows dicalcium silicate based structure. Magnesium is mostly present in the form of the following minerals: periclase, merwinite and melilite.

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Abstract  

Results obtained by the comparative investigations of the natural mineral marmatite (Zn,Fe)S (Stari Trg, Yugoslavia) oxidation process are presented in this paper. Determination of the oxidation process mechanism was done by thermal analysis methods: DTA-TG-DTG and DSC, while Mssbauer spectroscopy, X-ray and electronic microanalysis were used for phase composition determination of the products formed during the oxidation process. Kinetics of the process was defined for two temperature intervals 862–973 and 1023–1173 K, under isothermal conditions.

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Processes which occur during the thermal treatment of system FeSO4·7H2O-MnO2 are of the interest for obtaining MnSO4, which can be easily soluted in water and separated from impurities in manganese slime in zinc metallurgy. Results of the experimental investigations of such processes are given in this paper. Kinetic parameters for the previously defined mechanism were determined using Borchardt and Daniels method.

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The paper presents results of the experimental determination of the quantity of heat liberated during the thermoluminesence (TL) of natural calcite.

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