Abstract: The present disclosure generally relates to photonic crystals, for example, for thermophotovoltaic power generation, or other applications, and to systems and methods for bonding metals or other materials together. Certain aspects are generally drawn to tantalum or other refractory metals that are bonded to Inconel or another metal superalloy. The tantalum or other refractory metals may be used as a photonic crystal in certain instances, e.g., to produce emissions when heated. In other aspects, other materials can also be used. In some cases, there may be substantially no gaps present between the materials, which may facilitate heat transfer between the materials. In some embodiments, the materials can be forced to or bonded together by heating the materials such that one material is unable to expand without exerting a force on the other material.

Abstract: The present disclosure generally relates to fuel burners, for example, for use with photonic crystals as part of thermophotovoltaic power generators or with other thermal power generators. In certain aspects, fuel is supplied into a reaction tube and mixed between swirling streams of gases moving in opposite directions (e.g., clockwise and counterclockwise) within the tube. This may allow for rapid mixing and relatively complete oxidation or combustion of the fuel. Heat may be extracted from the heated exhaust and may be supplied to a thermal power generator to produce power. For example, the heat may be supplied to an emitter comprising a photonic crystal, which can be used to direct electromagnetic radiation to a thermophotovoltaic cell to produce power. In addition, certain embodiments are directed to relatively small burners, e.g., that can burn fuel at less than 20 ml/min to produce power.

Abstract: An apparatus for generating electricity via thermophotovoltaic (TPV) energy conversion includes a metallic combustor to convert fuel into heat. The apparatus also includes a metallic photonic crystal to emit electromagnetic radiation within a predetermined wavelength band in response to receiving the heat from the combustor. A brazing layer is disposed between the combustor and the photonic crystal to couple the combustor with the photonic crystal. The apparatus also includes a photovoltaic cell, in electromagnetic communication with the photonic crystal, to convert the electromagnetic radiation emitted by the photonic crystal into electricity.

Abstract: A solar thermal photovoltaic device, and method of forming same, includes a solar absorber and a spectrally selective emitter formed on either side of a thermally conductive substrate. The solar absorber is configured to absorb incident solar radiation. The solar absorber and the spectrally selective emitter are configured with an optimized emitter-to-absorber area ratio. The solar thermal photovoltaic device also includes a photovoltaic cell in thermal communication with the spectrally selective emitter. The spectrally selective emitter is configured to permit high emittance for energies above a bandgap of the photovoltaic cell and configured to permit low emittance for energies below the bandgap.

Abstract: A solar thermal photovoltaic device, and method of forming same, includes a solar absorber and a spectrally selective emitter formed on either side of a thermally conductive substrate. The solar absorber is configured to absorb incident solar radiation. The solar absorber and the spectrally selective emitter are configured with an optimized emitter-to-absorber area ratio. The solar thermal photovoltaic device also includes a photovoltaic cell in thermal communication with the spectrally selective emitter. The spectrally selective emitter is configured to permit high emittance for energies above a bandgap of the photovoltaic cell and configured to permit low emittance for energies below the bandgap.

Abstract: Inventive systems and methods for the generation of energy using thermophotovoltaic cells are described. Also described are systems and methods for selectively emitting electromagnetic radiation from an emitter for use in thermophotovoltaic energy generation systems. In at least some of the inventive energy generation systems and methods, a voltage applied to the thermophotovoltaic cell (e.g., to enhance the power produced by the cell) can be adjusted to enhance system performance. Certain embodiments of the systems and methods described herein can be used to generate energy relatively efficiently.

Abstract: Inventive systems and methods for the generation of energy using thermophotovoltaic cells are described. Also described are systems and methods for selectively emitting electromagnetic radiation from an emitter for use in thermophotovoltaic energy generation systems. In at least some of the inventive energy generation systems and methods, a voltage applied to the thermophotovoltaic cell (e.g., to enhance the power produced by the cell) can be adjusted to enhance system performance. Certain embodiments of the systems and methods described herein can be used to generate energy relatively efficiently.

Abstract: A metal detectable glove is provided, including a plurality of unaltered fibers, and a plurality of altered synthetic fibers containing a metal, wherein the unaltered fibers and the altered synthetic fibers are knitted together to form the metal-detectable glove. Methods and means of manufacturing such metal detectable gloves are also provided.

Abstract: A magnetic sleeve apparatus intended to be wrapped around the wrist of the wearer includes an outer sleeve and an inner sleeve configured to vary in length and joined with each other at their respective edges to form a continuous seamless cylindrical sleeve body. A magnetic sleeve apparatus further includes one or more lengths of magnetic material disposed in communication with the outer sleeve and the inner sleeve. A magnetic sleeve further includes an elastic band configured to admit to a plurality of configurations and one or more material pockets configured to contain the one or more lengths of magnetic material.