摘要:
A method that redistributes light from a light source. The controller can redistribute light to make an irradiance profile of the light source more uniform or make the irradiance profile match a fluid flow profile. The irradiance profile may be controlled by modifying light leakage from a plurality of waveguides or changing the light-directing properties of reflectors and/or lenses.
摘要:
A concentrated solar energy system includes a photovoltaic cell, an optical concentrator, a heat removal system, and means for providing thermal contact between the photovoltaic cell and the heat removal system. The optical concentrator is configured to direct concentrated solar energy to the photovoltaic cell such that the photovoltaic cell generates electricity and heat. The heat removal system removes heat from the photovoltaic cell. The means for providing thermal contact provides an effective thermal conductivity per unit length between the photovoltaic cell and the heat removal system of greater than about 50 kilowatts per square meter per degree Celsius.
摘要:
A system and method that redistributes light from a light source. The controller can redistribute light to make an irradiance profile of the light source more uniform or make the irradiance profile match a fluid flow profile. The irradiance profile may be controlled by modifying light leakage from a plurality of waveguides or changing the light-directing properties of reflectors and/or lenses.
摘要:
The substrate cell surfaces of a catalytic air purifier are so structured as to disrupt the occurrence of laminar flow along the flow path of the fluid passing therethrough. A plurality of substrates are connected in serial flow but axially offset relationship to obtain improved performance. Also, the dimensional aspects of the individually cells are selected so as to maintain adequate mass-transfer coefficient and UV photon penetration depths throughout the length thereof.
摘要:
A tungsten oxide/titanium dioxide photocatalyst coating oxidizes contaminants in the air that adsorb onto the coating into water, carbon dioxide, and other substances. The tungsten oxide forms a monolayer on the titanium dioxide. When photons of the ultraviolet light are absorbed by the tungsten oxide/titanium dioxide photocatalyst coating, an electron is promoted from the valence band to the conduction band, producing a hole in the valence band. The holes in the valence band react with water applied on the tungsten oxide/titanium dioxide photocatalyst coating, forming reactive hydroxyl radicals. When a contaminant in the air is adsorbed onto the tungsten oxide/titanium dioxide photocatalyst, the hydroxyl radical attacks the contaminant, abstracting a hydrogen atom from the contaminant. The hydroxyl radical oxidizes the contaminant, producing water, carbon dioxide, and other substances. The tungsten oxide/titanium dioxide photocatalytic coating has low sensitivity to humidity variations.
摘要:
A membrane electrode assembly includes an anode, a cathode, a membrane disposed between the anode and the cathode, a catalyzed layer in at least one position selected from the group consisting of between the cathode and the membrane and between the anode and the membrane, and an edge seal positioned along an edge of the membrane electrode assembly, wherein the membrane and the catalyzed layer extends into the edge seal.
摘要:
An erosion resistant and hydrophobic article includes a core that has a first hardness and a surface on the core. The surface includes a plurality of geometric features that have a second, greater hardness. The geometric features define a surface porosity by area percent and a corresponding surface solidity by area percent. The surface includes a ratio of the surface solidity divided by the surface porosity that is 1.8 or greater. The geometric features and the ratio establish the surface to be hydrophobic, and the second, greater hardness and the ratio establish an erosion rate of the surface that is equal to or less than an erosion rate of the core under identical erosion conditions.
摘要:
A method of fabricating a ceramic component includes using vapor infiltration to deposit a ceramic coating within pores of a porous structure to form a preform body with residual interconnected porosity. Transfer molding is then used to deposit a heated, liquid glass or glass/ceramic material into the residual interconnected porosity. The liquid ceramic or ceramic/glass material is then solidified to form a ceramic component.
摘要:
An erosion resistant and hydrophobic article includes a core that has a first hardness and a surface on the core. The surface includes a plurality of geometric features that have a second, greater hardness. The geometric features define a surface porosity by area percent and a corresponding surface solidity by area percent. The surface includes a ratio of the surface solidity divided by the surface porosity that is 1.8 or greater. The geometric features and the ratio establish the surface to be hydrophobic, and the second, greater hardness and the ratio establish an erosion rate of the surface that is equal to or less than an erosion rate of the core under identical erosion conditions.
摘要:
A method for fabricating a ceramic material includes impregnating a porous structure with a mixture that includes a preceramic polymer and a filler. The filler includes at least one free metal. The preceramic polymer material is then rigidized to form a green body. The green body is then thermally treated to convert the rigidized preceramic polymer material into a ceramic matrix located within pores of the porous structure. The same thermal treatment or a second, further thermal treatment is used to cause the at least one free metal to move to internal porosity defined by the ceramic matrix or pores of the porous structure.