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Showing 1 to 17 of 17 for “"chromium oxide"”.
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Ruthenium-Chromium Oxide Aerogels Oxygen Evolution Electrocatalysts: Structure, Activity and Stability
… hydrogen and oxygen from water. Ruthenium-oxide based catalysts have shown the highest reported activities of any acidic OER catalysts, but their instability is a major roadblock for wider use. In this work, we report the synthesis, structure and properties of ruthenium-chromium oxide and …
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Carbothermic-vacuum reduction of chromium oxide in electrolytic chromium: a hybrid phenomenological-stochastic process simulation model
Includes bibliographical references (pages 179-180).
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A kinetic and mechanistic study on the oxidation of chromium oxide in pure chemicals and in ferrometallurgical slags
Chromium can exist in a number of oxidation states but the environmentally stable forms are trivalent (Cr(III)) and hexavalent (Cr(VI)) chromium. These two forms are noted for their different degrees of toxicity and mobility. Hexavalent chromium is more toxic and mobile and has been responsible for …
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Digestibilidade do farelo de urucum com adição de complexo enzimático para Tilápia do Nilo
… was performed by the indirect method, using chromium oxide (Cr2O3) as an indicator of digestibility. We used 45 male juvenile Nile tilapia with approximately 100.00 g were randomly distributed into three incubators adjusted for digestibility trial. The physical and chemical parameters of the …
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Electronic, magnetic and thermal properties of Pb₂₋x AxCrO₅ (A = K or La)
Lead chromium oxide is a photoconductive dielectric material tha t has great potential of being used as a room temperature photodetector. In this research, we made ceramic pellets of this compound as well as potassium doped compound Pb2-xKxCr05, where x=O, 0.05, 0.125. We also investigate the …
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Evaluation of metal dusting of nickel-chromium-iron based alloys in a laboratory environment
… reduction plants, petroleum refineries, carbon dioxide cooled nuclear plants, fuel cells using molten salts and hydrocarbons, and the recycle-gas loop equipment of coal-gasification units. The consequence of carbon deposition is a metal related degradation phenomenon known as "Metal dusting". …
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Investigations of Structure–Property Relationships in Semicrystalline Thermoplastic Polymers: Blown Polyethylene Films and Polyacrylonitrile Copolymers
… (HDPE) blown films. The use of metallocene and chromium oxide based resins allowed the effects of MW and MWD on orientation behavior to be studied. All films possessed Keller-Machin low stress morphologies oriented along the film MD. Under identical processing conditions, the narrower MWD resins …
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Adsorption of Model Fuel Additives at the Metal/Oil Interface
… found that the steel surfaces consist of iron oxide and a mixture of iron and chromium oxide respectively. Depth profiling experiments on the stainless steel revealed a Cr-enriched region not directly at the surface, but in a region just below. However, it is clear that the principle exposed …
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Frictional oscillations in elastomeric sliding
… and fluorocarbon. The hard counterfaces include chromium oxide, aluminum, epoxy paint, and glass. Various combinations of these materials were tested in an elastomeric hemisphere-on-flat configuration. Three regimes of sliding have thus far been identified: 1. Steady state sliding where the …
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Stress corrosion cracking and crack tip characterization of Alloy X-750 in light water reactor environments
… These regions are enriched in both oxygen and oxide with the oxide being a chromium-nickel spinel. 2) The matrix ahead of each finger-like "tunnel" is enriched in oxygen and predominantly chromium oxide. This indicates that oxygen is diffusing ahead of the crack tip into the bulk material. 3) …
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Metal oxide modified tubular ceramic membrane for the separation of oil-in-water emulsion.
… on modifying microporous asymmetric Aluminium Oxide (Al2O3) tubular ceramic membranes with metal oxides nanoparticles for surface wettability to improve hydrophilicity and increase O/W emulsion separation efficiency. A novelty material – Magnesium Oxide (MgO) - nanoparticles modified tubular …
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Geometric and Electronic Structure Sensitivity of Methyl and Methylene Reactions on α-Cr₂O₃ and α-Fe₂O₃ surfaces
… effects in hydrocarbon reactions over metal oxides have been examined by comparing the reactions of methyl (-CH₃) and methylene (=CH₂) fragments on three different oxide single crystal surfaces: α-Cr₂O₃(101̅2), α-Cr₂O₃(0001), and α-Fe₂O₃(101̅2). The intermediates have been generated through …
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Erosion - corrosion mechanisms of stainless steel UNS S31603
… was partly due to the continuous rupture of the oxide film leading to an erosion enhanced corrosion synergistic effect. The erosion-corrosion rates were found to be a function of the kinetic energy of the particles, the number and the size of the particles impacting the surface. The amount of …
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Halocarbon Reactions on the Chromium (III) Oxide (101̲2) Surface
A nearly stoichiometric, (1×1) Cr₂O₃ (101̲2) surface was prepared from a single crystal of α-Cr₂O₃. The five-coordinate cations exposed at the stoichiometric surface dissociatively adsorb molecular oxygen to form a (1×1), terminating chromyl (Cr=O) layer that is stable to >1100 K. TDS and AES were …
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Aspects of the chemistry of milk protein films formed on stainless steel
… of positively charged colloids of iron oxide, chromium oxide or calcium phosphate. Deposition by evaporation of solution films, or precipitation from solution are other mechanisms by which macroscopic films may be formed. The film thicknesses of the drained milk films formed after …
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Improving Nutrient Utilization and Growth in Dairy Heifers
… (N) balance and body composition. Deuterium oxide (D2O) dilution methods have been used for assessment of body composition because it is an alternative method to direct chemical analysis and considered a noninvasive technique that provides for economical and repeatable methods. Estimated body …
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Interaction of Acid/Base Probe Molecules with Specific Features on Well-Defined Metal Oxide Single-Crystal Surfaces
Acid/Base characterizations of metal oxide surfaces are often used to explain their catalytic behavior. However, the vast majority of these studies have been performed on powders or supported oxides, and there is very little information available in the literature on the interaction of acid/base …