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Abstract  

The molar heat capacities of the pure samples of acetone and methanol, and the azeotropic mixture composed of acetone and methanol were measured with an adiabatic calorimeter in the temperature range 78–320 K. The solid–solid and solid–liquid phase transitions of the pure samples and the mixture were determined based on the curve of the heat capacity with respect to temperature. The phase transitions took place at 126.160.68 and 178.961.47 K for the sample of acetone, 157.790.95 and 175.930.95 K for methanol, which were corresponding to the solid–solid and the solid–liquid phase transitions of the acetone and the methanol, respectively. And the phase transitions occurred at 126.580.24, 157.160.42, 175.500.46 and 179.740.89 K corresponding to the solid–solid and the solid–liquid phase transitions of the acetone and the methanol in the mixture, respectively. The thermodynamic functions and the excess thermodynamic functions of the mixture relative to standard temperature 298.15 K were derived based on the relationships of the thermodynamic functions and the function of the measured heat capacity with respect to temperature.

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change at the transition pressure lies at 9%. So far, there has been considerable controversy for the phase transition of TiN. On the other hand, to the best of our knowledge, the thermodynamic properties of TiN have not previously been reported. So, we

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Abstract  

Polyimide BTDA-ODA sample was prepared by polycondensation or step-growth polymerization method. Its low temperature heat capacities were measured by an adiabatic calorimeter in the temperature range between 80 and 400 K. No thermal anomaly was found in this temperature range. A DSC experiment was conducted in the temperature region from 373 to 673 K. There was not phase change or decomposition phenomena in this temperature range. However two glass transitions were found at 420.16 and 564.38 K. Corresponding heat capacity increments were 0.068 and 0.824 J g–1 K–1, respectively. To study the decomposition characteristics of BTDA-ODA, a TG experiment was carried out and it was found that this polyimide started to decompose at ca 673 K.

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Abstract  

Thermodynamic properties of pure titanium stannides obtained by crucible-less growth techniques under vacuum are determined by differential scanning calorimetry and Knudsen effusion. The enthalpy, specific heat capacity, entropy and Gibbs energy temperature dependence were simulated using Maier and Kelly equations. Standard enthalpies of evaporation, formation and atomization of titanium stannides were determined and compared with earlier-known data.

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A numerical study of the thermodynamic properties of a superconducting quantum cylinder in a longitudinal magnetic field is carried out. Closed-form expressions for the critical temperature, the free energy, the heat capacity jump, and the magnetization difference between the superconducting and normal phases as functions of the nanotube parameters are obtained in limit cases.

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Journal of Thermal Analysis and Calorimetry
Authors: Zh. V. Dobrokhotova, A. I. Zaitsev, M. A. Zemchenko, A. D. Litvina, B. M. Mogutnov, and S. N. Yaschenko

The thermodynamic properties of calcium and barium phosphides have been determined in the temperature range 1178–1537 K by a Knudsen effusion technique combined with massspectral analysis of the evaporation products.

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and their thermodynamical properties is experiencing recent activity because of its fundamental research interest and technological applications in the field of microelectronics and optoelectronics, as a substrate for high speed electrical and

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Journal of Thermal Analysis and Calorimetry
Authors: K. Sreekanth, M. Kondaiah, D. Sravana Kumar, and D. Krishna Rao

/isoamyl alcohols and N , N -dimethyl acetamide were added. The study of thermodynamic properties of these multi component liquid mixtures and data on the analysis in terms of various models are important for industrial and pharmaceutical applications [ 6 ] such as

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Thermodynamic properties of binary mixtures containing oxaalkanes

Part VI. Monoethers, acetals, diethers, cyclic mono- and di-ethers + tetrachloromethane

Journal of Thermal Analysis and Calorimetry
Authors: D. Falconieri, B. Marongiu, Alessandra Piras, Silvia Porcedda, and Enrica Tuveri

Abstract  

The data available in the literature on thermodynamic properties concerning different oxaalkanes + tetrachloromethane mixtures are examined on the basis of the DISQUAC group contribution model. The obtained interaction parameters, dispersive and quasichemical, depend on the intramolecular environment of the O atom. The steric effect results in a regular decrease of the quasichemical interaction parameters of the oxygen/tetrachloromethane (e,d)-contact in linear ethers. The proximity effect of the O atoms generates lower coefficients in dioxaalkanes with respect to monooxaalkanes and because of the ring strain, being the quasichemical coefficients constant, the dispersive parameters in cyclic molecule are higher than in linear ethers.

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size of the hydrophobic parts and the positional effect of polar groups of a guest molecule on inclusion reactions, the thermodynamic properties of inclusion complexes of CD with aliphatic alcohols and other alcohols have been investigated

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