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Showing 1 to 16 of 16 for “"chromia"”.
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Kinetics of Methylcyclohexane Dehydrogenation to Toluene on Chromia - Alumina
Made available in DSpace on 2014-12-05T17:15:39Z (GMT). No. of bitstreams: 1 6202996.pdf: 2530041 bytes, checksum: 7fa9324af7952dc087106ea8bdf387d2 (MD5) Previous issue date: 1962
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Haloethane Reactions over the Chromia Cr₂O₃ (1012) Surface
Ethyl iodide and ethyl chloride have been used as reactants to produce ethyl fragments on the stoichiometric α-Cr₂O₃ (1012) surface by means of thermal dissociation. Ethyl iodide is dissociated giving iodine adatoms and ethyl fragments bound to surface Cr cation sites, while ethyl chloride is …
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Model Chromia Surface Chemistry: C<sub>2</sub> Alkyl Fragment Reactions and Probe Molecule Interactions
The thermally induced reaction of chlorinated ethanes on the nearly-stoichiometric α-Cr₂O₃ (102) surface results in the formation of gas phase hydrocarbons including ethylene, ethane, acetylene, 2-butene, 2-butyne and dihydrogen, and deposition of surface chlorine adatoms. No surface carbon or …
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Kinetics of carbide dissolution in chromium + molybdenum steels during oxidation
… then pre-oxidised in H2+10%H2O to grow a purely chromia scale. In this low oxygen partial pressure environment, carbides in the alloy's sub-surface dissolved and formed a ferritic precipitate-free zone. The precipitate dissolution model developed by previous investigators was then tested and …
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Synthesis and characterisation of pillared clay catalysts for hydro-cracking of heavy liquid fuels
A range of chromia pillared montmorillonite and tin oxide pillared laponite clay catalysts, as well as new pillared clay materials such as cerium and europium oxide pillared montmorillonites were synthesised. Methods included both conventional ion exchange techniques and microwave enhanced methods …
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Crystallisation of PFA glasses
… magnesium carbonate. Titania or ferric oxide and chromia were used as nucleants. Various crystallisation heat treatments were carried out and the nucleation and crystallisation behaviour was studied. A minimum MgO:CaO was found to be necessary for bulk nucleation to occur. The activation energy …
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Growth mechanisms of carbon nano-fibers, -tubes, and graphene on metal oxide nano-particles and -wires
… the CNFs. Potential catalytic CNS activity of chromia, vanadia, ceria, lithia and alumina NPs are explored, establishing for the first time CNT growth from chromia and vanadia precursor-derived NPs, although the phases of those NPs are not determined during growth. The insights acquired from …
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Alkali attack on coal gasifier refractory lining
… atmosphere, the reactions between fired alumina-chromia solid solution refractories and alkali (sodium and potassium) with and without sulfur at varying alkali concentrations were thermodynamically calculated using the SOLGASMIX-PV computer program and the results were experimentally confirmed. …
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Formulation and Process of Powder Coating for Solid Oxide Fuel Cell Interconnects
… cell (SOFC) interconnects, which are made of chromia-forming ferritic stainless steels, are used to connect individual SOFCs in series to increase the overall cell voltage output. They are usually exposed to high operating temperature (around 800oC) and both oxidative and reductive atmosphere. …
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Effect of Vanadium on High Temperature Corrosion of Alloy Steel
… (FeO), magnetite (Fe3O4), hematite (Fe2O3), and chromia (Cr2O3). SEM/EDS images proved that the scale is getting thicker as temperature increases in air. In addition, the oxide scale formed at lower temperatures tends to be non-adhesive and easy to come off, while at higher temperatures remains …
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Physical, mechanical and environmental properties of fired clay bricks incorporated with palm oil mill waste
… within the brick matrix by forming lead ferrite, chromia, gahnite and jacobsite. Meanwhile, the incorporation 5% of POMW (1°C/min) into fired clay brick positively contribute to the energy saving from 5.5% to 13.4% due to the embodied energy stored in POMW released during the firing process and …
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Laboratory simulation of metal dusting corrosion
… This was attributed to a protective surface chromia layer that prevented carburisation of the specimens. During the second test series, specimens of Incoloy 800H in the sensitised condition showed a high susceptibility to metal dusting. Carburisation of the matrix carburisation was …
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Development of Low-Cost Polycrystalline Nickel-Base Superalloys for Gas Turbine Applications
… at 700˚C and 800˚C. The alloys were found to be chromia forming, with internal oxidation of Al forming a discontinuous subscale. Significant microstructural degradation was observed at 800˚C due to the formation of the δ phase, with the differences in oxidation behaviour rationalised using …