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Journal of Thermal Analysis and Calorimetry
Authors: A. Iddaoudi, N. Selhaoui, M. Ait Amar, K. Mahdouk, A. Aharoune, and L. Bouirden

Conclusions The phase diagram of the Lu–Pb binary system has been optimized based on the experimental data and phase diagram data from literature. A set of self-consistent thermodynamic parameters have been obtained, which can reasonably reproduce the

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Journal of Thermal Analysis and Calorimetry
Authors: Amar M. Ait, M. Idbenali, N. Selhaoui, K. Mahdouk, A. Aharoune, and L. Bouirden

. Idbenali , M , Servant , C , Selhaoui , N , Bouirden , L . Thermodynamic assessment of the Ru–Zr binary system . J Phase Equilib 2007 26 : 243 – 249 . 2. Kaufman , L , Bernstein

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estimation. In addition, experimental data in literature are often contradictory. All of the lanthanide–alkali metal chloride binary systems have been successfully examined or reexamined at large by Seifert [ 1 ]. The phase diagrams of the homologous bromide

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side than the bulk. Up to now, little is known about the influence of confinement on phase behavior of a binary system. Normal alkanes are main components of mineral oil. The knowledge of structure and thermodynamic property of their mixtures is

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Abstract  

Results of the comparative thermodynamic analysis of the binary system Bi−Sb obtained by DTA measurements and predicting are presented in this paper. Activities, activity coefficients, partial and integral molar quantities for Bi and Sb at temperatures 973, 1073 and 1173 K in the investigated binary system Bi−Sb determined by DTA measurements and thermodynamic predicting are given. An excellent agreement between the experimental and predicted results is reached. Also, a phase diagram of the investigated system Bi−Sb obtained by DTA shows good agreement with literature and it can be concluded that DTA could be satisfactorily used for quantitative thermodynamic analysis of any binary system containing equilibrium between solid and liquid solutions. It was also determined that conclusion about linear dependence ofgKs constant for binary eutectic systems and systems with phase transformation is valid for binary system containing equilibrium between solid and liquid solutions too.

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Abstract  

Experimental results obtained by phase diagram investigation of Pb-In binary system are presented in the paper and compared with literature data. Liquidus and solidus temperatures, as well as cell parameters were determined, and structural analysis of this system was made. Microstructural analysis was done by SEM-EDX, crystallographic analysis was performed by diffractometry, while liquidus and solidus temperatures were determined by DTA. Obtained results show that in investigated system exist three areas: area reach in In, area reach in Pb and separating the intermediate phase (αIn). Experimental results show good agreement with literature.

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Abstract  

The melting and mixing enthalpy of the binary system nitrocellulose and N-nitrodiethanolamine dinitrate (DINA) was determined by DSC. The mixing enthalpy H max M = 1.95 kJ mol−1 had maximum at mass fraction x wDINA=0.46. The influence of samples storing on glass and endothermic transitions were studied. The temperature range of glass transition broadened with x wDINA what proved the increase of samples heterogeneity. For x wDINA≤0.750 no influence of samples storing on the phase changes was observed. The heat capacity change decreased and temperature range of glass transition increased for x wDINA≤0.500 what indicated the reduction of glass phase fraction in studied samples.

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Abstract  

The mixing and melting enthalpy of the binary system nitrocellulose+2,6-dinitrotoluene was determined using the DSC method. The mixing enthalpy of the components was calculated. At the melting temperature the maximum value of the mixing enthalpy for the mole fractionx w26DNT=0.607 is equal H M max= −3.41 kJ mol−1. Measurements of the melting process (second measurement) were conducted after a storage period of several days at room temperature. Analysis of the melting peaks shows that the melting process of 26DNT takes place in pores of the micro-fiber and bulk outside the fibers. In the case of a mass fraction of x w26DNT>0.9 the melting process takes place in the bulk, which suggests that in the case of such concentrations separation of the micro-fibers occurs.

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Abstract  

A method of gelation enthalpy determination of nitrocellulose (NC)+s-diethyldiphenylurea (Centralite 1, C1) binary system was elaborated using the change of Centralite 1 melting enthalpy in the mixture. The heats of C1 melting together with gelation and dissolution of NC fibres were determined by DSC calorimetric methods. A sharp maximum of the gelation enthalpy for C1 mole fraction x C1 max =0.555 suggests that the complex is very stable and one partly nitrated anhydroglucose ring is interacting with about 1.25 C1 molecules. The gelatinization enthalpy maximum equals
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\bar H_{max}^M$$ \end{document}
=−4.59 kJ mol−1.
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Abstract  

Melting enthalpy and mixing enthalpy of binary system 2,4-dinitrotoluene and nitrocellulose were determined by DSC method. The maximum value of mixing enthalpy was H max M=1.38 kJ mol−1 for molar fraction x w24DNT = 0.501. The Flory-Huggins parameter (c) was estimated. The solubility curves and glass transition temperatures were predicted and compared with the experimental results. The measurements were performed for the samples with different times of storage at room temperature. The analysis of melting peaks for the mixture leads to the conclusion that for the long periods of storage the melting of 2,4-dinitrotoluene takes place in the confined spaces (pores) and unconfined space (bulk). The crystallization and melting is observed during the short time of storage in mixtures with low nitrocellulose content and in the case of mixtures with a large amount of NC the glass transition is additionally observed.

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