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Showing 1 to 20 of 26 for “"Tungsten oxide"”.
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Doped tungsten oxide nanocrystals for next generation electrochromic windows
Doped tungsten oxide (WO₃ [subscript -x]) nanocrystals (NCs) have lots of potential for next generation electrochromic windows compared to bulk thin films. The difference lies in intrinsic WO₃ [subscript -x] NC properties of shape and crystalline anisotropy with localized surface plasmon resonance …
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Kinetics of propylene disproportionation over a tungsten oxide on silica catalyst
… kinetics of propylene disproportionation over a tungsten oxide on silica catalyst. A catalyst of ten percent WO₃ on silica gel (223 square meters per gram B.E.T. surface area) was used in a microcatalytic reactor. Electron probe scans of the commercially prepared catalyst showed that the standard …
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Investigating the interfacial process and bulk electrode chemistry in tungsten oxide electrochromic materials
… various functional materials, transition metal oxides are still one of the main choices due to their tunable chemical compositions and diverse crystal structures in most aqueous and organic electrolytes. The charge transfer process mainly occurs at the electrode-electrolyte interface, and …
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Break-in behavior of a tungsten oxide on silica catalyst during propylene disproportionation
… of a study of the break-in behavior of a tungsten oxide on silica catalyst during propylene disproportionation. A catalyst of 10 percent WO3 on silica gel (223 square meters per gram B.E.T. surface area) was used in a microcatalytic reactor. During the initial contacting of freshly …
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Synthesis and characterization of tungsten oxide wo3 nanostructures thin films for gas sensing applications
… of a room temperature gas sensor based on tungsten oxide (WO3) thin films. The synthesis of WO3 thin films was carried out using a direct current (DC) reactive magnetron sputtering at different deposition temperatures (300, 400 and 500 ºC). The deposition time, pressure, power, oxygen and …
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Enhancing the photoelectrochemical water splitting characteristics of titanium and tungsten oxide based materials via doping and sensitization
… Due to the inherent wide gap, such metal oxides absorb only ultraviolet radiation. Since ultraviolet radiation only composes of 4% of the sun's spectrum, the wide band gap results in lower charge collection and efficiency. Thusto improve optical absorption and charge separation, it is …
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The break-in behaviors of the cobalt oxide-molybdena-alumina catalyst and the tungsten oxide on silica catalyst during propylene disproportionation
… during propylene disproportionation. A cobalt oxide-molybdena-alumina (CoO-MoO₃—Al₂O₃) catalyst was found to undergo a rapid increase in the catalytic activity during the first 100 seconds of contacting with the reactants and this was the order of magnitude of the mass transport delays. A …
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Schaltbare optische Schichten : vom atomistischen Verständnis des gasochromen Schaltens von Wolframoxid zur industriellen Anwendung
… (few nanometers of Platinum or Palladium) tungsten oxide films of some hundred nanometers color in hydrogen containing atmosphere blue because of an absorption with a maximum in the infrared region. In oxygen containing atmosphere the films bleach. This coloration and bleaching is …
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Effects of flow on the activity of a WO₃-SiO₂ olefin disproportionation catalyst
… of the reactant flow rate on the activity of a tungsten oxide on silica catalyst during propylene disproportionation. A 10 percent tungsten oxide on silica catalyst (223 square meters per gram B.E.T. surface area) was used in a microcatalytic reactor. The catalyst activity was found to increase …
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Untersuchung gasochrom schaltender Wolframoxide
Analysis of gasochromic switching tungsten oxide layers This thesis describes the properties of reactively dc-magnetron sputtered tungsten oxide (WOx) films. The films are gasochromically switched with diluted hydrogen (H2) in argon or nitrogen, with a very thin surface film of palladium (Pd) as …
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Mechanical stresses upon phase transitions
… of coatings were studied. Transition metal oxides are used as optical coatings, hard coatings, etc., phase change films find application in optical data storage technology, while optically switchable coatings have been applied in switchable windows, rear-view mirrors etc. For all materials …
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Porous anodic aluminum oxide scaffolds; formation mechanisms and applications
Nanoporous anodic aluminium oxide (AAO) can be created with pores that self-assemble into ordered configurations. Nanostructured metal oxides have proven to be very useful as scaffolds for growth of nanowires and nanotubes with tunable diameters and with tight diameter distributions. For 50 years, …
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Mechanisms and catalyst design for heterogeneous Olefin metathesis
… reliance on decades-old catalyst technology like tungsten oxide on silica. This poor performance can be attributed to a lack of understanding of heterogeneous metathesis reaction mechanisms and the catalysts involved. Current understanding proposes that olefin metathesis follows the Chauvin …
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Functionalization of metal-organic frameworks with early transition metals : from fundamental studies to catalytic applications
… developed in the previous chapter to rhenium oxide-based olefin metathesis, which is unique compared to catalysis using molybdenum and tungsten oxide systems.
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Exploring approaches to functional surface modifications using an atmospheric plasma jet printer
… was also tested, using micron-sized amorphous tungsten oxide particles stabilised by oxalic acid in an aqueous solvent. Coherent films were formed, which appeared to be made up of clusters of the colloidal particles, which retained the same size as in the original suspension. The residence time …
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Fundamental studies on surface chemistry and interfacial interactions of nanoscale heterostructures for chemical sensing, photocatalysis, and thermal transport management
… or semiconducting quantum dots; (2) metal oxide heterostructures for photocatalysis and electrocatalysis: cobalt oxide (Co3O4) nanowires were grown on the cobalt foil using a water vapor-assisted thermal oxidation method. These Co3O4 nanowires were further decorated with tungsten oxide …
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Protonic All-Solid-State Electrochemical Device as an Artificial Synapse for CMOS-Compatible Neuromorphic Computing
… PdHX as the gate/proton reservoir and tungsten oxide (WO₃) as the switching channel, and characterize the performance of these devices. We examined the thickness effect of the electrolyte on the device operation. We show that devices built on porous Gd:CeO₂ electrolyte can perform …
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Development of hybrid inorganic-organic light-emitting devices with metal oxide charge transport layers
… thin films of thermally evaporated zinc-tin oxide (ZTO) with various ZnO and SnO2 compositions and studied its optical, electrical and morphological properties. After optimization of transparency and conductivity, these ZTO films showed promising materials for alternate transparent conducting …
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First-Principles Studies of Complex Oxide Materials
… uses first-principles methods to study complex oxide materials. The first part of the thesis deals with complex oxide materials that have applications as lithium-ion battery electrodes. In the second part, a new method for the calculation of vibrational properties of correlated materials, …
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Ceramic composites with solid lubricants processed by pulsed electric current sintering
… Formation of oxygen deficient lubricious metal oxides were first observed during wear of Al2O3 + Mo composites at 400 °C. Tungsten oxide of the same type was then implemented as a solid lubricant additive in ZrO2 + W20O58 composites. Oxygen deficient metal oxides, i.e., Magnéli oxides of …
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