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Abstract  

The phase diagram of R(+)-S(-) efaroxan hydrochloride (Tfus.(R)=245.10.3C. ΔHfus.(R)=119.63.0 J g-1) shows a racemic compound. The melting temperature and melting enthalpy of the compound are: Tfus.(RS)=247.80.2C and ΔHfus. (RS)=124.62.4 J g-1. A solid ↔ solid transformation takes place at Ttrs.=1801C, ΔHtrs.=15.00.4 J g-1. This transition is observed between 3 and 97% R(+). The stability of the racemic compound already established in a previous study was confirmed by the value of Petterson's coefficient (i=1.19). The two eutectic positions at 20 and 80% R(+) that define the range over which the racemic compound is found, exclude the use of resolution methods by preferential crystallization.

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Abstract  

The phase diagram of the binary AgNO3–CsNO3 system was constructed using differential thermal analysis (DTA) technique in the range 300–700 K. The apparatus is described briefly. The results exhibit a congruently melting compound CsNO3·AgNO3 (m.p.=453 K) characterized by two allotropic varieties and , an incongruently melting compound AgNO3·CsNO3 (m.p.=450 K) with three forms , and , two eutectics (16 mol% CsNO3, 442 K and 32.5 mol% CsNO3, 445 K) and a peritectic (38mol% CsNO3, 450 K). The occurrence of the transitions of intermediates was confirmed by X-ray diffraction at variable temperatures. The phase diagram exhibits also two plateaus at 429 K and 435 K corresponding to the phase transitions of CsNO3 and AgNO3, respectively.

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Journal of Thermal Analysis and Calorimetry
Authors: V. Dvořák, V. Danielik, O. Matal, Marta Chrenková, and M. Boca

Abstract  

The phase diagram of the binary system NaF-SnF2 was determined by using the thermal analysis method. In addition to the crystallisation fields of pure components the formation of three other crystallisation fields was observed and these were attributed to the compounds: NaF·2SnF2, NaF·SnF2 and 2NaF·SnF2. The coordinates of the four eutectic points are: e 1: 70 mol% NaF, 30 mol% SnF2 and 255°C e 2: 58 mol% NaF, 42 mol% SnF2 and 238°C e 3: 44 mol% NaF, 56 mol% SnF2 and 246°C e 4: 18 mol% NaF, 82 mol% SnF2 and 191°C The model independent on the real structure of the melt was applied for the calculation of phase diagram comprising the calculation of excess molar Gibbs energy of mixing. The probable inaccuracy in the calculated phase diagram is σ=2.0°C. XRD analysis of solidified mixtures was performed in order to confirm the formation of expected compounds.

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Abstract  

The Al-Zn-Ga ternary phase diagram was earlier established by thermodynamic modellization [1], but no experimental study appears to have been carried out on this system, except for measurements of mixing enthalpies in the liquid [2]. The present experimental study was carried out by thermal analysis and X-ray diffraction at various temperatures, using the isopletic cuts method. Four isopletic cuts were established and two others were partly studied in the Al-rich corner of the diagram. On these cuts, two isobaric ternary invariant reactions were determined: a eutectic reaction at 231C, and a metatectic reaction at 1231C. Evidence was found for the existence of a retrograde miscibility of Ga in a solid solution α′SS which protrudes into the ternary system starting from the Al-Zn binary up to a Ga concentration of about 30%*.

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ternary phase diagrams for the apparent fusion heat with the composition (ternary H – X phase diagrams) have been constructed. The ternary T – X phase diagrams (the temperature dependence on composition) for the two ternary systems have been

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Journal of Thermal Analysis and Calorimetry
Authors: S. Wacharine, D. Hellali, H. Zamali, J. Rogez, and M. Jemal

and their phase diagrams contributes to give information for their use. Complete phase diagram of the CsNO 3 –RbNO 3 system has never been reported in literature. Wallerant [ 1 ], Blidin [ 2 ] ( Fig. 1 a) studied only the liquidus in a range

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Journal of Thermal Analysis and Calorimetry
Authors: M. Boča, V. Danielik, Z. Ivanová, E. Mikšíková, and B. Kubíková

Abstract  

The phase diagrams of the systems KF-K2TaF7 and KF-Ta2O5 were determined using the thermal analysis method. The phase diagrams were described by suitable thermodynamic model. In the system KF-K2TaF7 eutectic points at x KF=0.716 and t=725.4°C and at x KF=0.214 and t=712.2°C has been calculated. It was suggested that K2TaF7 melts incongruently at around 743°C forming two immiscible liquids. The system KF-Ta2O5 have been measured up to 8 mol% of Ta2O5. The eutectic point was estimated to be at x KF∼0.9 and t∼816°C. The formation of KTaO3 and K3TaO2F4 compounds has been observed in the solidified samples.

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Abstract  

The phase diagram for the AgNO3−KNO3 system has been determined using differential scanning calorimetry (DSC). Eutectic point has been found at 391 K andX Ag=0.580 mole fraction AgNO3. The DSC curves indicate the existence of an intermermediate compound (AgNO3·KNO3) in the KNO3-rich region of the phase diagram. This compound was identified in the solid phase by X-ray diffraction. The melting and the crystallization processes were followed with the aid of a hot stage microscope, too.

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Abstract  

The Al–Ga–Zn ternary phase diagram presents two isobaric invariant reactions: a eutectic at 231C and a metatectic at 1231C [1–3]. Calorimetric measurements on the two isobaric invariant reactions have been carried out. First the Tammann method has enabled us to determine the composition of their limits on five isopletic cross sections. Then, the compositions of the invariant phases have been determined.

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Phase diagram of V2O5-MoO3-Ag2O system

Part III. Vanadium-rich part of the diagram

Journal of Thermal Analysis and Calorimetry
Authors: E. Wenda and A. Bielański

Abstract  

The results concerning the synthesis, structure and thermal properties of V2O5-MoO3-Ag2O samples in the vanadium rich region of ternary system are presented in the form of quasi-binary phase diagrams in which at constant V2O5/MoO3 molar ratios, equal 9:1, 7:3 and 1:1, the content of Ag2O was variable. A new ternary phase isostructural with NaVMoO6 has been detected in the investigated system.

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