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Ouzegane, K., S. Boumaza 1996: An example of ultrahigh-temperature metamorphism: orthopyroxene-sillimanite-garnet, sapphirine-quartz and spinel-quartz parageneses in Al-Mg granulites from in Hihaou, in Ouzzal, Hoggar. - J. Metamorph. Geol., 14, pp. 693

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Reaction Kinetics, Mechanisms and Catalysis
Authors: R. Thinesh Kumar, N. Clament Sagaya Selvam, T. Adinaveen, L. John Kennedy, and J. Judith Vijaya

Introduction Nanostructured metal aluminate spinels constitute an interesting class of oxide ceramics with important technological applications such as lower temperature sinterability, greater thermal stability, increased

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Nano-crystalline Mn0.3Ni0.3Zn0.4Fe2O4 obtained by novel fumarato-hydrazinate precursor method

Synthesis, characterization and studies of magnetic and electrical properties

Journal of Thermal Analysis and Calorimetry
Authors: U. B. Gawas, V. M. S. Verenkar, and S. C. Mojumdar

Introduction Spinel ferrites are investigated in the recent years for their useful electrical and magnetic properties which find applications in information storage systems, magnetic bulk cores, magnetic fluids, microwave

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–titanium samples of Types A and B consisted of single-phase spinel. In the initial state their lattice parameters were a = 8.368 Å and a = 8.370 Å, respectively. This implies that vacuum annealing of the powder is followed by an increase in the lattice

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Abstract  

Sulphur substitution of oxygen in LiMn2O4 spinel destroyed the ideal symmetry of MnO6 octahedrons. In consequence, the phase change at about room temperature is strongly retarded, manifested by lowering heat of the transition and hysteresis of the temperature dependence of electrical conductivity. The optimal conditions for preparation of sulphur substituted spinel LiMn2O4–ySy have been determined.

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], magnetic high-density information storage [ 4 ], catalysis [ 5 ], energy storage [ 6 ], and gas sensors [ 7 ]. Ferrites can occur in several different crystal structure forms. Within this group, spinel is a kind of the most important structure that occurs

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Nanocrystalline Zn0.5Ni0.5Fe2O4

Preparation and kinetics of thermal process of precursor

Journal of Thermal Analysis and Calorimetry
Authors: Wenwei Wu, Yongni Li, Kaiwen Zhou, Xuehang Wu, Sen Liao, and Qing Wang

Introduction Polycrystalline spinel ferrites have many unique properties, such as high electrical resistivity, high Curie temperature, large magnetocrystalline anisotropy, high coercivity, mechanical hardness, chemical

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Dick, H., B., T. Bullen 1984: Chromian spinel as a petrogenetic indicator in abyssal and alpine-type peridotites and spatially associated lavas. - Contrib. Mineral. Petrol., 86, pp. 54 - 76 . Chromian spinel as a petrogenetic

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Journal of Thermal Analysis and Calorimetry
Authors: C. Santos, B. Capistrano, F. Vieira, M. Santos, S. Lima, E. Longo, C. Paskocimas, A. Souza, L. Soledade, and I. Santos

Abstract  

In this work, spinels with the general formula Zn2−xCoxTiO4 were synthesized by the polymeric precursor method and thermally treated at 1,000 °C. The powder precursors were characterized by TG/DTA. A decrease in the DTA peak temperature with the amount of zinc was observed. After the thermal treatment, the characterizations were performed by XRD, IR, colorimetry and UV/VIS spectroscopy. The XRD patterns of all the samples showed the presence of the spinel phase. Infrared spectroscopy showed the presence of ester complexes for Zn2TiO4 after thermal treatment at 500 °C, which disappeared after cobalt addition, indicating that organic material elimination was favored.

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Journal of Thermal Analysis and Calorimetry
Authors: D. Gouveia, A. Souza, M. de Maurera, C. da Costa, I. Santos, S. Prasad, J. de Lima, C. Paskocimas, and E. Longo

Abstract  

Using the Pechini method, pigments with spinel structure (Zn7Sb2O12)were synthesized by substitution of the cation Zn2+ by Co2+, in compounds with different concentrations of Sb2O3. The doping resulted in CoxZn(7–x)Sb2O12 phases(x=1–7) that were isomorphs to spinel, denominated as samples A and B. After thermal treatment at 400C for 1 h, the powders were characterized by thermogravimetry(TG) and differential thermal analysis (DTA). The results indicate a different behavior whena higher amount of Sb2O3 is used, due to the presence of a secondary phase (ilmenite).

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