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appreciable amount of the third element (Al), forming ternary solid solutions whose homogeneity ranges are at a constant Dy content: Dy(Al x Si 1− x ) 2 , 0 ≤ x ≤ 0.1, Dy(Al x Si 1− x ) 1.67 , 0 ≤ x ≤ 0.2, DyAl x Si 1− x , 0 ≤ x ≤ 0.2 and Dy 5 (Al x Si 1

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solid solution of Pt and Pt–Ir alloy containing mercury. In the present work, mercury films were electrodeposited on Pt–Rh (20 mass%) alloy foils, and the mercury was removed by thermal desorption, as described previously [ 11 , 16 – 23 ], and

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Alexander Khassin, Georgiy Filonenko, Tatyana Minyukova, Irina Molina, Lyudmila Plyasova, Tatyana Larina, and Vladimir Anufrienko

allows supposing Cu 2 O phase formation and XRD proves decomposition of Cu–Mg oxide solid solution and formation of two individual oxide phases—Cu 2 O and MgO. One should note that the decomposition of Cu 0.15 Mg 0.85 O in air wasn't observed even at

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Journal of Thermal Analysis and Calorimetry
Authors: P. Byszewski, E. Kowalska, R. Diduszko, R. Aleksiyko, M. Berkowski, J. Fink-Finowicki, and J. Kapuśniak

Abstract  

The solid solution crystals, La1–xNdxGaO3 and La1–xPrxGaO3 have been studied by differential scanning calorimetry method; the crystals exhibit the first order phase transition, the temperature of the transition linearly increases with the concentration of Pr or Nd. The structure of the crystals has been determined by X-ray diffraction. The correlation between the phase transition temperature and crystalline structure at the temperature of the phase transition in both solid solution families is discussed.

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Abstract  

The analysis of structural state and energetic properties of active catalyst component in oxide copper-containing catalytic system has been performed on the basis of comparing the data of thermochemical, X-ray diffraction and catalytic activity determinations. The analysis of thermochemical data obtained makes it possible to evaluate changes in lattice energy and the nearest coordination sphere energetic parameters of copper cations during the formation of solid solutions. The high degree of correlation of catalytic properties and the formation enthalpy of solid solutions can be explained by the fact that alongside with the factors influencing the catalytic activity it is the strength of cation—cation interaction that is the most important.

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Abstract  

Beside four approaches to the thermodynamics of GaSb-M(=S, Te) solid solutions the doping limits for extremely narrow concentration regions are analysed and ranked in the Cu, Ge, Mn (p-dopants), S, Se, Te (n-dopants) and N, In (isoelectric) groups.

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Abstract  

DSC was used for heat capacity measurements of pure RuO2 in the temperature range from 300 to 1170 K of solid solutions corresponding to the compositions of (Ti1−x Rux )O2 (x ≤0.15 and x ≥0.85) and in the temperature range from 300 to 1550 K of pure TiO2. The analysis of experimental data obtained within 2% of accuracy has shown that the characteristic temperatures representing the harmonic lattice vibrations do not strongly depend on the chemical composition x . It was demonstrated that non-harmonic heat capacity is strongly correlated to x. The existence of additional excess heat capacity was observed with the mixed oxide solid solution samples of low Ru content and explained by the defect formation model.

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Abstract  

The first part of this paper presented five experimental isopletic cuts in the Al-Zn-Ga ternary phase diagram. On these cuts, two isobaric ternary invariant reactions were determined and a significant retrograde miscibility of Ga in a α′SS solid solution was observed. In the second part, the two isobaric invariant reactions are studied more precisely. In particular, the composition of the invariant phases are given and the Ga miscibility in the αSS ternary solid solution is studied. Isothermal sections are established. The results confirm the existence of a vanishing point in the liquidus area, conjugated with a ternary critical point at about 290C. A general perspective shape of the equilibria in the diagram is proposed.

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Abstract  

Heat capacity measurements were carried out on Pb1-xLaxWO4+x/2 (x=0.2) and Pb1-xLa2x/3WO4 (x=0.2, 0.5) solid solutions prepared by sintering and mechanical alloying (MA) methods. For all the solid solutions, sintered samples showed slightly larger heat capacity around 100 K in comparison with MA samples, which was presumably caused by the excitation of mobile oxide ion motion. For sintered scheelite-type structured PbWO4s, high-temperature synthesis introduced oxide ion interstitials even for the Pb1-xLa2x/3WO4 system, which resulted in the excess heat capacity at low temperature for excitation. On the other hand, for the samples prepared by room-temperature MA technique, oxide ion seemed to occupy the regular sites rather than interstitial ones and excess heat capacities were not observed.

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Summary Mechanical mixtures containing zirconia xerogel and increasing amount of crystalline yttria up to 40 mol%, were hydrothermally treated by microwave route at 110°C for 2h. All the treatments were performed in the presence of (KOH+K2CO3) mineralizer solution at concentration 0.2 M. Amorphous and hydrated ZrO2-Y2O3 solid solutions with yttria content up to 33.3 mol% (corresponding to Zr/Y molar ratio equal to 1), resulted after the hydrothermal treatments. A remarkable reduction of the surface area has been detected at increasing yttria content of the amorphous phases with a corresponding increase of the exothermic peak of crystallization. A mechanism of reaction for the formation of the amorphous solid solutions has been proposed.

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