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Showing 1 to 12 of 12 for “"Rietveld method"”.
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The study of intermetallic particles in aluminium alloy AA3104 can-body stock during homogenisation
… light microscopy, image analysis, XRD and the Rietveld method. The SEM micrographs show a larger quantity of smaller, more closely dispersed intermetallic particles at the edge of the ingot, compared to those at the centre. The β-Al₆(Fe,Mn) phase is more geometric in shape, while the …
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Revestimentos a base de Ta/Al2O3 produzidos por aspersão térmica sobre substrato metálico
… respectively by X-ray diffraction and the Rietveld method. Morphology by scanning electron microscopy and chemical analysis by energy dispersive spectroscopy EDS. It was also performed measurements of the substrate roughness, Vickers microhardness measurements in sprays and determination of …
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Diffraction investigations of cement clinker and tricalcium silicate using Rietveld analysis
… constituents, there is currently no reliable method to quantitatively determine the composition of cement. Partly this arises from the fact that the crystal structure of the main component of cement, tricalcium silicate, has not been fully determined. There has been an increase in the use of …
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A study of the synthesis, structure, and ionic conductivity of sodium and lithium lanthanide pyrosilicates, A3LnSi2O7
… silicates, Na3LnSi2O7, were made by the ceramic method. The meta-stable Li-silicates, Li3LnSi2O7, were formed by a molten salt ion exchange of Li+ for Na+ in Na3LnSi2O7. Structural models for the two compounds were refined against powder X-ray and neutron diffraction data using the Rietveld …
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Structural variations of feldspars at high pressure and high temperature
… Na-rich plagioclases that were refined using the Rietveld method indicate that the major structural response to increased temperature involves tilting of the tetrahedra. Building on ideas originally proposed by Dr. Helen Megaw, the changes in the conformation of the tetrahedral framework of …
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Aerosol synthesis and Rietveld refinement of Pd2Zn
PdZn catalysts have been proven to be a viable option to replace current Cu catalysts for methanol steam reforming. The change in selectivity to CO2 that makes this a possibility has been attributed to the formation of tetragonal β1-PdZn at treatment temperatures of 500oC. Through the course of …
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Structural and thermodynamic properties of sodium actinide ternary oxides
… Np-O system was then developed using the CALPHAD method. This is particularly relevant since it is envisaged to incorporate minor actinides into the fuel to minimize the nuclear waste inventory. The poorly known structures of the Na- Np-O and Na-Pu-O phases diagrams, i.e., tetravalent $Na_2AnO_3$ …
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QUANTITATIVE EVALUATION OF THE CONSOLIDATING EFFECTS INDUCED BY INORGANIC MINERAL TREATMENTS APPLIED ON POROUS CARBONATE STONE SURFACES
… techniques are complemented by laboratory methods for initial assessments. The first manuscript published in the framework of this research activity investigates the crystallization kinetics of DAP-treated in porous Noto limestone using SR-μCT to track porosity changes over time, revealing …
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Fabrication, Kinetics and Crystallography of Lithium Disilicate Glass-Ceramics
… and/or disilicate), which is refined by Rietveld method from the as-received synchrotron XRD data, and discuss the relationship of phase transition and crystallographic evolution. Firstly, a lithium disilicate glass-ceramic, based on a well-documented SiO2–Li2O–Al2O3– P2O5–ZrO2 glass …
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Phase formation and structural transformation of strontium ferrite SrFeOx
… diffraction,thermogravimetric and calorimetric methods,scanning electron microscopy and Mossbauer spectroscopy. Changes in the oxide were induced using conventional thermal treatment in various atmospheres as well as mechanical energy (ball milling). ¶ ...
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Phase formation and structural transformation of strontium ferrite SrFeOx
… diffraction,thermogravimetric and calorimetric methods,scanning electron microscopy and Mossbauer spectroscopy. Changes in the oxide were induced using conventional thermal treatment in various atmospheres as well as mechanical energy (ball milling). ¶ ...