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Showing 1 to 20 of 33 for “"Phase Purity"”.
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Synthese, Charakterisierung und magnetische Eigenschaften von Nitriden des Typs MMFe3N
… the temperature profile during synthesis on the phase purity. For this purpose it was necessary to set up a new oven system. Thus, the phase purity of RhFe3N was raised up to 94%. With the improved product quality the magnetic and optical characterization was possible. Like the archetype Fe4N, …
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Structural Characterisation of Heteroepitaxial Zincblende Gallium Nitride
… zincblende GaN grown by metal-organic vapour phase epitaxy is stabilised on 3C-SiC/Si substrates with a miscut, ranging from 0° to 4°. Crystalline zincblende GaN nucleates as elongated islands which coalesce with increasing GaN deposition. Annealing of nucleation layers reduces the substrate …
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Structural Characterization and Thermoelectric Performance of ZrNiSn Half-Heusler Compound Synthesized by Mechanical Alloying
… samples were compared and analyzed for phase purity. Thermal conductivity, electrical conductivity and Seebeck coefficient are measured as a function of temperature in the range 300 K to 800 K and compared with measurements reported for high temperature solid state reaction synthesis of …
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Toward the rational design of multifunctional nanomaterials: synthesis and characterization of functionalized metal-organic frameworks
… how the synthesis conditions affect the phase purity and the in-situ reaction of ligands.
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Variation von Kristallinität und Stöchiometrie in mittels PLD hergestellten Schichten aus Galliumoxid, Galliumnitrid und Bariumzirkonat
… The characterization of the film crystallinity, phase purity and short range structural order was completed by means of X-ray diffraction and X-ray absorption spectroscopy. The stoichiometry was investigated using electron probe microanalysis. For analyzing the correlation between the structure …
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Synthesis and properties of some doped lithium transition-metal phosphates
… a reducing atmosphere of 2%H₂/98%N₂ to achieve phase purity. Attempts were made to substitute all four materials with aliovalent dopants. Li₃Fe₂(PO₄)₃ and Li₃V₂(PO₄)₃ underwent a phase change depending on dopant content to a higher ionic conducting phase. AC impedance spectroscopy was used to …
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Structural and optical properties of phase transition cubic phase gallium nitride for photonic devices
… Despite its success, the conventional hexagonal-phase GaN has fundamental deficits that hinders performance. These include: internal polarization field (~MV/cm2), high acceptor activation energy (260 meV), low hole mobility (20 cm2/V), and expensive substrates (Al2O3, SiC). The metastable …
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Synthesis and properties of some electrolyte additives and electrode materials for lithium-ion batteries
… with x ≥ 10% was not beneficial for LVO as phase purity deteriorated, as shown by their XRD showing dopant oxide peaks. Chromium doping was the most successful since it did not show any secondary phase; even at high concentrations it was well incorporated in the orthorhombic crystal …
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Model updating of modal parameters from experimental data and applications in aerospace
… multi-point excitation force vectors for Phase Resonance Testing is introduced. The method is unique in that it is based entirely on experimental data, allows to determine both the locations and force components resulting in the highest phase purity, and enable to predict the corresponding …
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Optimisation of hydroxyapatite (HAp) for orthopaedic application via the chemical precipitation technique
… is largely dependent on the coating morphology, phase composition, particle size and crystallinity of the powders pre-coating application. The present study aims to synthesise phase pure HAp powders via the wet chemical precipitation technique, in order to evaluate the critical process parameters …
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Scale-up and optimisation of the β-chloroacrylamide process by batch and continuous flow methods
… yield the final product with optimum quality and phase purity. The first chapter of this thesis presents an overview of the mechanistic pathway leading to the formation of these compounds along with the different process tools available for optimisation. It covers the various factors for …
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Enhancement In Electrochemical Performance Of Advanced Battery Electrodes Using Carbon- Nanomaterial Composites
… nano-composites by a sol-gel method. The phase purity of the nano LiFePO4/Graphene composite was confirmed by X-Ray diffraction. Addition of graphene improved the electronic conductivity of LiFePO4 by six orders of magnitude. Scanning electron microscopy and transmission electron …
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ZnO Nanostructures: Low-Temperature Synthesis, Characterisation, Their Potential Application as Gene-Delivery Tools
… microscopy (AFM). The crystalline structure, phase purity, and particle size of ZnO nanomaterials have been investigated using X-ray diffraction (XRD). The outcomes from all these efforts have been integrated for cellular investigation via fluorescence microscopy technique (FM) to demonstrate …
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Production of silver-loaded zeolites and investigation of their antimicrobial activity
… XRD analysis showed little or no changes in the phase purity of all zeolites before and after ion exchange or before and after substitution of silver ions. SEM analysis and particle size analysis showed that the morphology of each zeolite particles was closely related before and after ion …
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Alumina-aluminum Titanate-titania Nanocomposite: Synthesis, Sintering Studies, Assessment Of Bioactivity And Its Mechanical And Electrical Properties
… were performed for a systematic understanding of phase evolution from the synthesized gel. X-Ray diffraction technique was used to confirm the phase evolution, phase purity, crystallite size and crystal structure(s) of the phase(s). Calcination of the powder at low temperatures (700°C) leads …
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Novel, High Activity Hydroprocessing Catalysts: Iron Group Phosphides
… also prepared on a silica (SiO₂) support. The phase purity of these catalysts was established by x-ray diffraction (XRD), and the surface properties were determined by N₂ BET specific surface area (Sg) measurements and CO chemisorption. The activities of the silica-supported catalysts were …
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Microstructure and Texture of Yttrium-Nickel-Borocarbide and Samarium-Cobalt Thin Films
… giving rise to the formation of secondary phases. On the other hand, using an artificial Y2O3 buffer layer secondary phases are suppressed. The texture of the Y2O3 layers determines the texture of the YNi2B2C film. The superconducting properties of the borocarbide films are discussed with …
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Half-Heusler Thermoelectric Materials and Modules
… conditions were controlled to achieve the phase purity, desired microstructure and the enhanced charge-carrier transport. Optimized n-type and p-type compositions are found to exhibit zTmax ~ 1 at 773 K. Chapter 5 describes breakthrough in decoupling of TE parameters in n-type half-Heusler …
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Chemical crystallography at the interface of physics, chemistry, and in engineering: structure determination of highly correlated extended solids, main group compounds, coordination complexes, and bioceramics
Multi-disciplinary research is essential to address the major challenges in science, engineering, and medicine. For these three areas, crystallography has played and continues to play a huge role by providing researchers with the means to determine the structure of a compound and relate these to …
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The modification of Laponite® with silver or copper and investigation of their antibacterial activity
… microscopy (TEM). The XRD showed changes in the phase purity of pure and modified Laponite® RD. The amount of silver or copper exchanged or incorporated into Laponite® RD interlayer or sheet were determined by EDX. The TEM image analysis indicated that the Ag+ and Cu2+ ions were in the nanometer …
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