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with the similar melting point. Due to the closeness of temperatures of these two effects, in the experiment conditions another solid product was not found. Phase equilibria in the system FeVO 4 –CuO The objective of

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Abstract  

The phase equlibria established in the Zn3V2O8–ZnMoO4 system over the whole component concentration range up to 1000C have been investigated. A phase diagram has been constructed using the results of DTA and XRD methods.

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This work is a part of the systematic study of the ternary based chalcogenides systems. The aim is to determine the phase equilibrium, and to determine the limits of the phase area. This is done in view to perfecting knowledge of elaboration conditions for new materials and to study of their physical properties. Few works have been devoted to the study of the ternary system Se-Te-Sn, only the cross section SnSe-SnTe has been studied [1] and [2]. The experimental study by DTA, DSC and X-ray diffraction on powder performed at room temperature, exhibits a miscibility gap in the liquid state which narrows as it goes through the Sn-Se binary system. Three cross sections behave as ‘quasi-binary‘ system and six ternary invariants have been exhibited: three ternary eutectics and three ternary quasi-peritectics.

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It has been shown by the methods of X-ray powder diffraction (XRD), differential thermal analysis (DTA) and infrared spectroscopy (IR) that solid solutions of a formula Cr1−xAlxVMoO7, where x& (0−0.65), are formed in the system CrVMoO7-AlVMoO7. The obtained research results have proven that the ions Al3+ are incorporated into the crystal lattice of CrVMoO7 instead of Cr3+, which causes a contraction of the lattice and a shift of IR absorption bands towards higher values of wavenumbers. The phases Cr1−xAlxVMoO7 melt incongruently in the temperature range from 710C (for x=0.65) to ∼820C in the case of x close to zero

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The reactivity of iron(III) orthovanadate(V) towards zinc divanadate(V) in the solid state was investigated over the whole component concentration range. On the base of DTA and XRD measurements the phase diagram of the FeVO4-Zn2V2O7 system in the subsolidus area was constructed for the whole component concentration range.

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We construct with a differential scanning calorimeter (DSC) a phase diagram for the ethylene carbonate (EC)-dimethyl carbonate (DMC) binary system for its liquid-solid phase equilibria. We determine the eutectic composition of the binary system using an enthalpic method that we devised based on the composition dependence of the enthalpy of solidus melting, with highly consistent results. We also discuss the merits and limitations of this enthalpic method.

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Journal of Thermal Analysis and Calorimetry
Authors: A. Atbir, L. Aneflous, A. Marrouche, M. El Hadek, R. Cohen-Adad, and M.-Th. Cohen-Adad

Abstract  

Polytherm diagram of the ternary system KCl–FeCl2 –H2 O between 0 and 70C. Phase equilibria in the KCl–FeCl2 –H2 O system were studied over the temperature range 0–70C by conductimetric and analytical methods. A solubility polytherm of the system was constructed. We have observed the crystallization fields of the KCl and FeCl2 6H2 O (at 0C), KCl and FeCl2 4H2 O (at 15, 30 and 40C) and KCl, FeCl2 4H2 O and of a double salt KClFeCl2 2H2 O are obtained at 70C.

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Electrical conductivity of solid systems AgX-MX2 (where M=Cd, Co, Zn and X=Cl, Br) were measured in a large range of temperature and compositions. Activation energies and conductivity values vs. composition are presented and discussed in relation to phase equilibria in the respective systems. Maximum of the conductivity value and stabilization of the activation energy have been found for silver halides doped heavily with divalent cation e.g. in the systems forming solid solutions on the silver halide side. Disorder in AgBr on the approach to melting, expected to be higher than in AgCl, has been shown by means of original DSC curves presented for both halides.

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Phase equilibria in subsolidus area in the ZnO-V2O5-Fe2O3 system have been investigated over the whole concentration range of the oxides. The components of this system form two compounds: Zn2FeV3O11 and Zn3Fe4(VO4)6. A solidus area projection onto the component concentration triangle plane of the ZnO-V2O5-Fe2O3 system has been constructed using DTA and XRD methods. 11 subsidiary subsystems can be distinguished in this system. Melting temperatures of mixtures of solid phases coexisting at equilibrium in each of subsidiary subsystems were determined.

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