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Abstract  

The phase equilibria in the system AlVMoO7-V2O5 were investigated over the whole component concentration range up to 1000C. A phase diagram was constructed from the results of DTA and XRD methods.

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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  

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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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  

Reactivity of FeVO4 towards Ni2V2O7 and Ni3V2O8 in the solid state was investigated. On the base of XRD and DTA results, phase diagrams in subsolidus area of the FeVO4-Ni2V2O7 and FeVO4-Ni3V2O8 intersections of the ternary system NiO-V2O5-Fe2O3 have been worked out and the phase diagram of this ternary system in subsolidus area in the whole component concentration range has been verified.

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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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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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