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Russian Journal of General Chemistry - 相似文献
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We report a novel approach for fabrication of cubic ZrWMoO8 applying a melt quenching method. The stoichiometric mixture of ZrO2, WO3 and MoO3 in a 1:1:1 M ratio was melted and quenched at room temperature by pouring the melts between two metal plates. The quenched sample was characterized by X-ray diffraction (XRD), differential thermal analysis (DTA) and scanning electron microscopy (SEM) analysis. As quenched material is polyphase contains above 70% ZrWMoO8. The obtained composite is thermal stable up to 930 °C. The ZrWMoO8 was indexed as cubic with a lattice parameter a = 9.1263 (3) Å calculated by the “PowderCell” program. By SEM observation it was established that the microstructure of bulk composite material is built up of one-direction orientated agglomerates with cuboid crystal morphology. 相似文献
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Polycrystalline K2.5Bi2.5Ti4O13 (I) is prepared by solid state reaction of KNO3, Bi2O3, and TiO2 (Al2O3 crucible, 750 °C, 16 h). 相似文献
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Chun‐Hai Wang Maxim Avdeev Brendan J. Kennedy Michael Kuepers Chris D. Ling 《ChemInform》2016,47(42):no-no
Polycrystalline gaudefroyite‐type YCa3(CrO)3(BO3)4 with Cr3+ ions (3d3, S = 3/2) forming an undistorted Kagome lattice is prepared by reaction of a stoichiometric mixture of Y2O3, CaCO3, Cr2O3, H3BO3 in a KCl flux (Al2O3 crucible, 1000 °C, 1 d) followed by re‐grinding and further annealing (1000 °C, 2 d, 95% yield). 相似文献
28.
T. Yu. Chemekova O. V. Avdeev S. S. Nagalyuk E. N. Mokhov Kh. Khelava Yu. N. Makarov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(6):1136-1139
Currently, wafers of aluminum nitride cut from bulk aluminum nitride crystals (AlN) grown by sublimation are considered promising
substrates for obtaining light-emitting diode structures based on nitrides of the third group. In this study, the structural
characteristics and electrical properties of AlN, as a prospective substrate material for light-emitting diode heterostructures
based on AlGaN/GaN, were investigated. The substrate working surface ((0001) plane, Al-polar) was specifically prepared for
epitaxial growth using chemical-mechanical polishing. The surface roughness (“epi-ready”), as estimated by atomic force microscopy,
did not exceed 0.3 nm. 相似文献
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Maxim Avdeev Andrei Kholkin 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e539-e540
The crystal structure of the low-temperature Na4Ti5O12 (tetrasodium pentatitanium dodecaoxide) phase has been solved and refined from X-ray and neutron powder diffraction data at 295 K. The structure is trigonal, space group P3, with Z = 1, although it is pseudo-centrosymmetric. The O and Na atoms form a distorted close-packed structure, where Ti atoms occupy octahedral sites. 相似文献
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Alexander V. Avdeev Eldar V. Goriounov Mikhail M. Lavrentiev Jr. Renato Spigler 《Applied Mathematical Modelling》2009
A behavior-oriented diffusion model, governing the time evolution of the cross-shore position of coastal profiles, is studied. Here, two time-independent, space-varying coefficients, which embody the relevant physical properties, are identified simultaneously. Two sets of real data, the first measured over 10 years at Duck, in NC (USA), the second obtained over 39 years measurements at Delfland (Holland), have been processed numerically by a suitable “inversion algorithm”, earlier developed by the authors. This is based on the minimization of a certain cost functional in order to identify both coefficients. The numerical results, obtained by solving the diffusion equation with the so-determined coefficients, favorably agree with the real data, which fact validates and calibrates somehow the diffusion model under investigation. A short-term prediction is finally obtained for coastal profiles, using such a model. 相似文献