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An X-ray Diffraction Study of (NH4)2TeBr6 and Ce2TeBr6Das, Ajit Kumar 05 1900 (has links)
The crystal structures of (NH4)2TeBr6 and Ce2TeBr6 have been
reinvestigated using X-ray diffraction from powders and single crystals.
Three dimensional single crystal intensity data obtained photographically
have been used to refine these structures, which are of the cubic K2PtCl6
type, by a full matrix least squares analysis. The Te-Br bond is found
to be 2.70* in both crystals after correction for the thermal notion of
the atoms.
A phase transition in (NH4)2TeBr6 has been observed at about
183°K. Pros an examination of Weissenberg photographs taken at 163°K,
the low temperature phase is found to be tetragonal, space group p4/mnc
(D64h) with a « 7.501+/-0.005* and c =10.765*+/-0.005*. The transformation
in this case is probably similar to that reported in other isomorphous
crystals, e.g., K2snBr6.
A review of other crystals with similar structure is included
in this thesis and the theory of X-ray diffraction as applicable to the
present problem is discussed briefly. / Thesis / Master of Science (MSc)
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SYNTHESIS, SINTERING, AND ELECTRONIC CONDUCTIVITY STUDIES OF MEDIUM- AND HIGH-ENTROPY PEROVSKITE OXIDESGajjala, Sai Ram 01 May 2023 (has links) (PDF)
The application of the entropy concept to stabilize oxide systems opens the possibility of discovering new materials with unique structural and functional properties. High-entropy alloys and oxides, which are based on the entropy stabilization concept and composed of multi-principal elements, have the potential to tailor structural and functional properties to meet specific needs. The study of lanthanum-based perovskite materials that benefit from the entropy stabilization approach is a promising area of research.However, the inherent randomness of multi-principal elements presents new challenges, making it difficult to predict their behavior. To understand these difficulties, we have initiated a methodical investigation of La-based medium- and high-entropy perovskite oxides. This study focuses on the synthesis, characterization, sintering mechanism, and electrical conductivity properties of nine La1-xCax(A1/3, B1/3, C1/3)O3 medium-entropy perovskite oxide systems (A, B, and C = three combination of Cr or Co or Fe or Ni or Mn) and one La1-xCax(Cr0.2Co0.2Fe0.2Ni0.2Mn0.2)O3 high-entropy perovskite oxide system (for x = 0.1 to 0.3). This research aims to provide better understanding of: (1) synthesis process, (2) temperature of single-phase formation, (3) the impact of various combinations of multiple B-site transitional elements and Ca doping on crystal structure, and microstructure (4) sintering mechanism and (5) electrical conductivity properties.
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Liquid crystalline behavior of mesogens formed by anomalous hydrogen bondingJEONG, SEUNG YEON 24 June 2011 (has links)
No description available.
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Formation of Precursor Calcium Phosphate Phases During Crystal Growth of Apatite and Their Role on the Sequestration of Heavy Metals and RadionuclidesBorkiewicz, Olaf J. 13 December 2010 (has links)
No description available.
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The Effect of Chloride and Sulfate on the Mineralogy and Morphology of Synthetically Precipitated Copper SolidsMelton, Lisa Nicole January 2013 (has links)
No description available.
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X-ray Scattering Study of the Strain In Annealed SilicaSrour, Mohammed R. 12 June 2014 (has links)
No description available.
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The Lattice Parameter of Gamma Iron and Iron-Chromium AlloysFeng, Zhiyao 03 June 2015 (has links)
No description available.
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AN EXPERIMENTAL STUDY OF MAGNETIC AND STRUCTURAL PHASE TRANSITIONS AND ASSOCIATED PHENOMENA IN SELECTED NI-MN-DERIVATIVE HEUSLER ALLOYSBrock, Jeffrey Adams 31 July 2017 (has links)
No description available.
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SYNTHESIS AND CHARACTERIZATION OF NEODYMIUM SULFIDE BULK SAMPLES AND THIN FILMSTHACHERY, JUGUL RAVINDRAN 11 March 2002 (has links)
No description available.
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Environment and Human Response at Newark's Great CircleCulver, Emily G. 26 September 2011 (has links)
No description available.
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