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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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Abstract  

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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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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Abstract  

The eutectic binary phase diagrams of volatilizable energetic material 1,3,3-trinitroazetidine (TNAZ) with 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and 1-methyl-2,4-dinitroimidazole (MDNI) have been investigated by high pressure differential scanning calorimeter (PDSC), respectively. The liquefying and melting processes of TNAZ/RDX and TNAZ/MDNI volatilizable systems have been studied. On the basis of the data of apparent fusion heat and liquefying temperature, the phase diagrams of apparent fusion heat (H) with composition (X) and liquefying temperature (T) with composition (X) were constructed, respectively. The results showed that the gasification or volatilization of easy volatile energetic materials could be efficiently restrained by high pressure atmosphere, and the perfect and ideal phase diagrams can be constructed. The eutectic temperatures for TNAZ/RDX and TNAZ/MDNI are measured to be 95.5 and 82.3 °C, respectively. The eutectic compositions of mole ratios for the two systems are obtained to be 93.55/6.45 (TX method), 93.79/6.21 (H–X method) and 62.25/37.75 (TX method), 63.29/33.71 (HX method), respectively.

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The intermolecular interactions of molecules within the bilayer are responsible for the lipid organisation, e.g. domain formation, and the interaction and stabilisation of proteins within the lipid matrix. The mixing behaviour of lipids, which reflects the intrinsic molecular interactions, can be deduced from the shape of the phase diagram (temperature vs. mole fraction diagram), which is constructed from the analysis of heat capacity curves obtained by DSC. However, there are no objective procedures to determine the temperatures corresponding to the border lines of the coexistence region, i.e. the liquidus and solidus curves of the phase diagram. The main challenge to overcome is to develop an objective method for the correct determination of the onset and offset temperatures of the melting curve for every single transition curve in a standardized manner. The presented paper describes a procedure for the simulation of heat capacity curves. In a second step, based on the results from the heat capacity curve simulation, a phase diagram is calculated using a non-ideal, non-symmetric mixing model. The non-ideality parameters obtained from the calculation describe the intermolecular interaction of both components in a single phase region. Using this procedure, examples of the mixing behaviour of various binary phospholipid systems are analysed and it is shown how the mixing behaviour is influenced by external factors like e.g. the pH or ionic strength.

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Abstract  

A series of PA-TD mixtures were prepared and their thermal properties were studied by DSC and thermal conductivity measurement. The phase diagram of the binary system was constructed, which showed an eutectic behavior for the solid-liquid equilibrium line. The eutectic composition of the binary system was at the mass fraction of TD near 0.7 with an eutectic temperature of about 29°C. At TD side, PA was partially miscible in the TD solid matrix and the solid phase transition of TD had an effect on the solidus line. The eutectic composition mixture could be viewed as a new phase change material with large thermal energy storage capacity.

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Abstract  

Application of the Smith thermal analysis method [1] to the experimental determination of ternary alloy phase diagrams is illustrated by reference to a study of the Au−Pb−Bi system. This system, which is of interest in relation to soft-soldered interconnections in solid state device technology, exhibits a ternary eutectic and several transition peritectic reactions.

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Abstract  

Several experimental techniques were used to characterise the physicochemical properties of the TbBr3-NaBr system. The phase diagram determined by DSC, exhibits an eutectic and a Na3TbBr6 stoichiometric compound that decomposes peritectically (759 K) shortly after a solid-solid phase transition (745 K). The eutectic composition, x(TbBr3)=39.5 mol%, was obtained from the Tamman method. This mixture melts at 699 K. With the corresponding enthalpy of about 16.1 kJ mol-1. Diffuse reflectance spectra of the pure components and their solid mixtures (after homogenisation in the liquid state) confirmed the existence of new phase exhibiting its own spectral characteristics, which may be possibly related to the formation of Na3TbBr6 in this system. Additionally, the electrical conductivity of TbBr3-NaBr liquid mixtures was measured down to temperatures below solidification over the whole composition range.

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The phase equilibria in the Tl2Te-Bi2Te3 system were studied by means of cooling curve determination, differential thermal analysis and X-ray diffraction methods; the results obtained with the former two methods were compared. The phase diagram established for the system differed considerably from three others published previously.

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Abstract  

Uranyl hydration and solvation numbers of uranyl benzenesulfonate (BSU) aqueous-organic solutions have been determined by means of dynamic NMR spectroscopy technique. Three aqua-complexes have been found to exist in aqueous-acetone solution: [UO2 (U6H5SO3)2·4H2O] and [UO2(C6H5SO3)2·(H2O)n] where n=1 or 2 and anions are bridging bidentate. Transition from [UO2 (C6H5SO3)2·4H2O] to the higher aqua complexes begins at P>40. There is a disolvate in the non-aqueous solution of BSU in tri-n-butyl phosphate (TBP). Composition of aqueous and organic phase of the BSU-water-TBP ternary system has been determined at room temperature, allowing to produce the phase diagram of the system. The binodale position is related to the anion amphiphilicity. The solvation number determined for BSU in the organic phases corresponds exactly to the low temperature data and allows to observe BSU dehydration and desolvation in the region of mutual dissolution of water and the organic phase, as well as TBP and the aqueous phase.

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