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Abstract  

After briefly noting some development records in phase diagrams, the stoichiometry is dealt with in more details showing the structural layer ordering in the superconducting cuprates and mentioning some correlation between thermodynamics and BSC theory of superconductivity.

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Summary The temperature and pressure dependencies of the structure and transport properties of AgI1-xClx are studied by means of molecular dynamics. From the results of the calculations, the P-T phase diagram for the AgI0.8Cl0.2 system has been obtained. The phase diagram indicates that the superionic phase transition temperature increase with the application of pressure. It is also pointed out that AgI1-xClx has a tendency of phase separation.

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Summary  

Based upon the results of ac calorimetry and temperature scanning X-ray diffraction in the phospholipid/cholesterol system, the phase diagram was constructed by taking into account the ripple structure. From the analysis of the cholesterol concentration dependence of the modified ripple structure the cholesterol-rich state which lies in the higher cholesterol concentration than 20 mol% in the phase diagram is proposed. It is proposed that this is a fundamental complex that appears generally in lipid/cholesterol systems.

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Résumé  

Liquid-liquid phase diagrams have been determined for binary systems of pyridine+n-hexane, pyridine+n-heptane and pyridine+n-dodecane. A general quasi-chemical theory in terms of group surface interactions has been applied to compute these liquid-liquid phase diagrams.

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. A[27] The composition of the gas phase at the decomposition to Fe 2 O(SO 4 ) 2 is the same—reaction B . B The phase diagram of Fe–S–O system at 500 K ( Fig. 5 ) was presented in our previous publication [ 18 ]. The

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Abstract  

Starting from tabulated thermodynamic data of stable compounds in the Mo−O−Cl system, phase diagrams for the Mo−O−Cl system were developed on the basis of GIBBS' phase law by means of thermodynamic calculations. The behaviour of molybdenum trioxide in a temperature gradient tube was investigated experimentally under chlorinating conditions, using99Mo as indicator. The thermochromatografically separated compounds were characterized by their deposition temperature in the temperature gradient tube and by an activation analytical determination of their Mo/Cl ratio. The experimental results were compared with the calculated phase diagram.

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Abstract  

Discontinuous isoperibolic thermal analysis (ΔITA) is a phase diagram investigation technique applicable to organic components systems (with at least one liquid phase). The elementary signal is composed by the evolution of the temperature of the system vs. time after a composition shift. A theoretical analysis and a mathematical modeling of this signal show that the overall enthalpy exchanged multiplied by a proportional factor can be obtained. From different experiments, evidence is given that this semi-quantitative calorimetric measurement is reliable. Thus, ΔITA allows consistent and accurate descriptions of phase diagrams and is a real relative calorimetric measurement technique.

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Epoxy resin modified with a thermoplastic

Influence of modifier and reaction temperature on the phase separation

Journal of Thermal Analysis and Calorimetry
Authors: Joaquín López, Maite Rico, Carmen Ramírez, and Belén Montero

Abstract  

The effect of cure temperature and modifier proportion on the miscibility of an epoxy–amine system with a thermoplastic modifier was studied by analysis of phase diagrams, morphologies, and glass transitions. Phase diagrams for the system before and during reaction were obtained from a thermodynamic analysis of phase separation using a model based on Flory–Huggins theory. Different types of morphologies were observed and analyzed in function of cure temperature and modifier proportion. The validity of the thermodynamic model was checked by comparing with observed morphologies. Two glass transitions were observed for most of the modified systems indicating that a phase separation was occurred.

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Abstract  

Solid-liquid phase diagrams have been determined for binary systems of pyridine withn-alkanes. These diagrams show the existence of large regions of partial miscibility. A general quasi chemical theory in terms of group surface interactions [1] has been applied to compute these solid-liquid phase diagrams.

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The phase diagrams of binary organic systems of benzidine with pyrogallol andp-nitrophenol give a double simple eutectic type phase diagram showing formation of a 1∶1 molecular complex with congruent melting point and two eutectics. The growth data on the pure components, the eutectics and the molecular complexes, determined by measuring the rate of movement of growth front in a capillary, justify the square relationship between growth velocity and undercooling. While enthalpy of mixing values suggest intermolecular hydrogen bonding, the excess thermodynamic functions reveal strong interactions among the components forming eutectics and addition compounds.

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