Results 171 to 180 of about 5,849 (219)

Low temperature synthesis of spinel (MgAl2O4)

Materials Letters, 1997
Spinel (MgAl2O4) is prepared by a combined gelation-precipitation process from a mixed solution of sulphates of aluminium and magnesium. X-ray diffraction of gel samples calcined at different temperatures shows that a spinel-like phase starts forming at 600 °C and complete conversion is obtained at 1000 °C in 1 h.
Vinay Kumar Singh, Rakesh Kumar Sinha
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New synthesis methods of MgAl2O4 spinel

Journal of the European Ceramic Society, 2007
Abstract The paper presents a study concerning the influence of the precursors upon the synthesis temperature, particle size and morphology of the MgAl2O4 spinel. With this view there have been used by comparison three synthesis methods: thermal conversion of the heteropolynuclear complex combination resulted from the oxidation reaction of 1,2 ...
C. Păcurariu, I. Lazău, Z. Ecsedi, R. Lazău, P. Barvinschi, G. Mărginean   +5 more
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On Infrared Intensities of Spinel, MgAl2O4

Bulletin of the Chemical Society of Japan, 2005
Abstract In spinel (MgAl2O4), the strongest infrared band at 485 cm−1 shows less LO–TO splitting than the medium band at 670 cm−1. This unexpected relationship is explained in terms of the vibrational coupling of these TO modes. A new manner for evaluating the LO mode is proposed.
Isao Kanesaka, Yuichi Hayashi, Yoshiyuki Morioka   +2 more
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Dynamic response of transparent ceramic MgAl2O4 spinel

Scripta Materialia, 2011
The quasistatic and dynamic compressive strengths of transparent spinel (MgAl2O4) specimens with grain sizes of 0.4 and 1.4 μm are measured. The measured strengths and rate sensitivities of the spinel specimens are compared with another transparent ceramic material, AlON, with significantly coarser grains.
J. Kimberley, K.T. Ramesh
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Inversion in synthetic spinel: Fluorescence of Cr3+ ions in MgAl2O4 spinel ceramics

Journal of Luminescence, 2020
Abstract The fluorescence spectra of probe Cr3+ ions in MgAl2O4 spinel ceramics have been studied. The analysis of the spectra shows that the normal non-inverse spinel phase dominates the samples. The possibility of obtaining normal spinel by the standard high-temperature ceramics synthesis is established.
S.P. Feofilov, A.B. Kulinkin, N.M. Khaidukov   +2 more
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Tribological Behaviour of Transparent Spinel (MgAl2O4)

2022
The wear behaviour of transparent magnesium aluminate (MgAl2O4) was investigated for unlubricated sliding against chrome steel balls under different load (5, 10, and 15 N) conditions. The sliding speed and sliding distance were retained constant, i.e., 260 mms-1 and 157 m, respectively.
Divyansh Mittal, Jan Hostasa, Rajiv Kumar, Sandan Kumar Sharma   +3 more
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Self-Propagating High-Temperature Synthesis of MgAl2O4 Spinel

Inorganic Materials, 2020
Magnesium aluminate spinel, MgAl2O4, has been prepared by self-propagating high-temperature synthesis (SHS) in the MgO–Al2O3–Mg(NO3)2 ∙ 6H2O–Al–B system. The composition and structure of the synthesis product have been ascertained by X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. Using time-resolved X-ray diffraction (TRXRD)
N. I. Radishevskaya, A. Yu. Nazarova, O. V. L’vov, N. G. Kasatskii, V. G. Salamatov, I. V. Saikov, D. Yu. Kovalev   +6 more
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Synthesis and characterization of MgAl2O4 spinel nanowires

Journal of Materials Chemistry, 2003
MgAl2O4 spinel nanowires have been synthesized on an alumina substrate by reaction of magnesium oxide powders with graphite at 1350 °C in a flowing argon atmosphere. Transmission electron microscopy (TEM) images show that they have a diameter of 50–120 nm, and a length up to 500 micrometers.
Xingcai C. Wu, Yourong R. Tao, Zhijian J. Han, Boda D. Zhang   +3 more
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Slip Systems in Stoichiometric MgAl2O4 Spinel

1975
The mechanical properties of stoichiometric MgAl2O3 spinel single crystals have been investigated at high temperatures (∿1800°C). The slip system has been determined by slip trace analysis and electron microscopy to be {111} . This behavior is rationalized by analyzing the changes in atomic configuration around dissociated dislocations as they move ...
L. Hwang, A. H. Heuer, T. E. Mitchell
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Cathodoluminescence of Mn2+ centers in MgAl2O4 spinels

Journal of Luminescence, 1990
Abstract MgAl 2 O 4 :Mn spinels containing between 0 and 8% Mn by weight were prepared (a) by growth from an induction melt, and (b) by Mn + implantation into nonstoichiometric spinel crystals. Cathodolumenescence brightness measurements (520 nm emission band) were made as a function of Mn concentration on both (a) and (b), revealing increasing ...
R. Mlcak, A.H. Kitai
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