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Electrical characterization of electro-Ceramics
Published in Amit Sachdeva, Pramod Kumar Singh, Hee Woo Rhee, Composite Materials, 2021
Phase Identification: The most widespread use of this technique is the identification of crystalline solids. Each crystalline solid produces its own diffraction pattern, which can be compared with those in a database of known materials such as the Joint Committee of Powder Diffraction Standards database in order to identify the sample. The intensity of the lines are characteristic of that particular phase and its pattern thus provides a fingerprint of the material [13].
Physical Methods for Characterizing Solids
Published in Elaine A. Moore, Lesley E. Smart, Solid State Chemistry, 2020
Powder diffraction provides information about the crystal structure of a compound: (a) the positions of the reflections that are a result of the parameters and symmetry of the unit cell, and (b) the intensity pattern of the reflections caused by the 3D arrangement of atoms or molecules within the unit cell. Powder patterns can confirm whether two similar compounds, where one metal substitutes for another for instance, have an isomorphous structure or whether a compound with the same stoichiometry or composition has formed a different crystal structure because atoms or molecules are arranged differently (polymorphism).
Advanced Instruments: Characterization of Nanomaterials
Published in M. H. Fulekar, Bhawana Pathak, Environmental Nanotechnology, 2017
Powder diffraction is a scientific technique uses x-ray, neutron or electron diffraction on powder or microcrystalline samples for the characterization and determination of structure of materials. Every possible crystalline orientation ideally is represented equally in a powdered sample. The resulting orientation averaging causes the three-dimensional reciprocal space that is studied in single crystal diffraction to be projected onto a single dimension. Sometimes it is necessary in practice to rotate the sample orientation to eliminate the effects of texturing and achieve true randomness.
Automatic Rietveld refinement by robotic process automation with RIETAN-FP
Published in Science and Technology of Advanced Materials: Methods, 2022
Ryo Tamura, Masato Sumita, Kei Terayama, Koji Tsuda, Fujio Izumi, Yoshitaka Matsushita
Rietveld analysis is an indispensable technique in materials research [1–6]. Because the crystal structure can be determined from powder diffraction data, it has been widely used for structural analysis of all crystalline materials, including those for which single crystals cannot be obtained. Rietveld refinement is completed by refining various parameters, such as lattice constants, peak profile functions, and backgrounds. However, the refinement of these various parameters necessitates tedious manual trial and error, which consumes significant human resources and time. In many instances, Rietveld analysis specialists are required to accomplish this refinement. To automate this refinement process, we present a robotic process automation (RPA) system that can automate the estimation of parameters in Rietveld analysis on a personal computer.
Microstructure and corrosion behaviour of ferritic steel–Zr-based metal waste form alloys in simulated ground water
Published in Corrosion Engineering, Science and Technology, 2019
R. Priya, S. Ningshen, S. Murugesan, P. Parameswaran
Phase analysis of the samples were carried out with Inel X-ray powder diffractometer (Model INEL3000) using Cu Kα1 radiation (wavelength: 1.540596 Å), 40 kV acceleration voltage and 30 mA tube current. The diffraction patterns were recorded in the 2θ range of 10–100° simultaneously using the curved position sensitive detector. The recorded diffraction patterns were compared with the Joint Committee on Powder Diffraction Standards (JCPDS) files to identify the diffraction peaks. Transmission electron microscopy, TEM (Model CM200) with selected area diffraction pattern (SAD) was used to examine the phases present in the microstructure. Samples for TEM analysis were prepared by mechanical polishing up to 100 µm followed by electro polishing using the electrolyte 10% perchloric acid and methanol, to achieve a thin foil of 100 nm.
Synthesis of high-area chemically modified electrodes using microwave heating
Published in Chemical Engineering Communications, 2019
I. M. D. Gonzaga, A. C. A. Andrade, R. S. Silva, G. R. Salazar-Banda, E. B. Cavalcanti, K. I. B. Eguiluz
Physical characterizations were carried out by SEM in a JSM-6510LV microscope at a voltage of 1 kV (100 × magnification); by XRD using a Brucker D8 Advance diffractometer operating with CuKα generated at 40 kV and 40 mA cm−2, and by XRF in a S4PIONNER by Bruker-AXS2010. The diffraction patterns were compared with the Joint Committee on Powder Diffraction Standards database. The electrochemical tests were performed using a potentiostat/galvanostat PGSTAT302N (Metrohm-Pensalab) coupled to a Booster of 10 A. Accelerated stability tests were performed applying a current of 1.5 A and the working electrodes were considered inactive when their potential reached 10 V. EIS measurements was also carried out in 0.5 mol L−1 H2SO4 solution at an applied potential of 1.3 V (versus Ag/AgCl) corresponding to the OER onset for all CMEs studied. The measurements were obtained covering the frequency range of 1 mHz–10 kHz using a 5 mV amplitude sinusoidal disturbance.