Abstract: Protective coating to prevent sublimation are disclosed. More particularly, the protective coatings comprise one or more alkaline earth halide materials, or mixtures thereof, to prevent sublimation. The alkaline earth halide material of the coating can be judiciously selected to match the coefficient of thermal expansion (CTE) of the material of the external surface of the underlying substrate coated. The protective coatings may be advantageous for protecting external surfaces of thermoelectric materials, parts and devices at high temperature to prevent sublimation and material loss.

Abstract: A topological material includes a lattice crystalline structure; and a material defect in the lattice crystalline structure that is treatable by hydrogen passivation that chemically mitigates an electronic charge associated with the material defect. The lattice crystalline structure includes dangling bonds in an atomic arrangement of the material defect of the lattice crystalline structure, and the hydrogen passivation may apply hydrogen to chemically passivate the dangling bonds of the material defect. The hydrogen passivation may be achieved by diffusing hydrogen into common materials of the lattice crystalline structure. The hydrogen passivation may chemically and/or electrostatically neutralize an electronic activity associated with the material defect.

Abstract: Protective coating to prevent sublimation are disclosed. More particularly, the protective coatings comprise one or more alkaline earth halide materials, or mixtures thereof, to prevent sublimation. The alkaline earth halide material of the coating can be judiciously selected to match the coefficient of thermal expansion (CTE) of the material of the external surface of the underlying substrate coated. The protective coatings may be advantageous for protecting external surfaces of thermoelectric materials, parts and devices at high temperature to prevent sublimation and material loss.

Abstract: Method and system for wavelength thermophotovoltaic (WTPV) power generation. In one embodiment, the system comprises a refractory waveguide that collects broadband infrared light generated by a heat source; a filter that filters the collected broadband infrared light to generate narrow-band infrared light; and a thermophotovoltaic (TPV) converter, thermally de-coupled from the heat source, that receives the narrow-band infrared light and converts the received narrow-band infrared light to electrical power.

Abstract: Provided among other things is an electrical device comprising: a first component that is a semiconductor or an electrical conductor; a second component that is an electrical conductor; and a strong, heat stable junction there between including an intermetallic bond formed of: substantially (a) tin (Sn) or a mixture of Sn and indium (In) thereof, and (b) substantially nickel (Ni). The junction can have an electrical contact resistance that is small compared to the resistance of the electrical device.

Abstract: Method and system for wavelength thermophotovoltaic (WTPV) power generation. In one embodiment, the system comprises a refractory waveguide that collects broadband infrared light generated by a heat source; a filter that filters the collected broadband infrared light to generate narrow-band infrared light; and a thermophotovoltaic (TPV) converter, thermally de-coupled from the heat source, that receives the narrow-band infrared light and converts the received narrow-band infrared light to electrical power.

Abstract: A passive thermal oscillator combines a thermoelectric device and a passive analog electrical circuit to produce a time-oscillating temperature difference. The oscillator makes use of a temperature difference imposed across a thermoelectric device to produce a Seebeck voltage to periodically trigger electrical current to pass through a switch. The periodic electrical current causes periodic Peltier cooling producing a time-oscillating temperature difference across the thermoelectric device. There is no requirement for additional external energy input because the thermal energy generates a voltage that is used as the driving force. The operation is purely passive. So long as there is a temperature difference across the thermoelectric device, then the passive thermal oscillator oscillates. The passive thermal oscillator can integrate multiple energy conversion device technologies to operate cooperatively.

Abstract: A passive thermal oscillator combines a thermoelectric device and a passive analog electrical circuit to produce a time-oscillating temperature difference. The oscillator makes use of a temperature difference imposed across a thermoelectric device to produce a Seebeck voltage to periodically trigger electrical current to pass through a switch. The periodic electrical current causes periodic Peltier cooling producing a time-oscillating temperature difference across the thermoelectric device. There is no requirement for additional external energy input because the thermal energy generates a voltage that is used as the driving force. The operation is purely passive. So long as there is a temperature difference across the thermoelectric device, then the passive thermal oscillator oscillates. The passive thermal oscillator can integrate multiple energy conversion device technologies to operate cooperatively.

Abstract: Provided among other things is an electrical device comprising: a first component that is a semiconductor or an electrical conductor; a second component that is an electrical conductor; and a strong, heat stable junction there between including an intermetallic bond formed of: substantially (a) tin (Sn) or a mixture of Sn and indium (In) thereof, and (b) substantially nickel (Ni). The junction can have an electrical contact resistance that is small compared to the resistance of the electrical device.

Abstract: Provided among other things is an electrical device comprising: a first component that is a semiconductor or an electrical conductor; a second component that is an electrical conductor; and a strong, heat stable junction there between including an intermetallic bond formed of: substantially (a) indium (In), tin (Sn) or a mixture thereof, and (b) substantially nickel (Ni). The junction can have an electrical contact resistance that is small compared to the resistance of the electrical device.

Abstract: Provided among other things is an electrical device comprising: a first component that is a semiconductor or an electrical conductor; a second component that is an electrical conductor; and a strong, heat stable junction there between including an intermetallic bond formed of: substantially (a) indium (In), tin (Sn) or a mixture thereof, and (b) substantially nickel (Ni). The junction can have an electrical contact resistance that is small compared to the resistance of the electrical device.

Abstract: A method is provided for removing carbonaceous ash deposits from a light hydrocarbon gas combustion chamber. The method comprises contacting the gas combustion chamber containing the ash deposits with alkali metal hydroxide. The alkali metal hydroxide causes the ash to soften and in one embodiment, to flake off, often down to bare metal. The combustion chamber can be part of a spark-ignited engine run on natural gas or propane.

Abstract: A sectioning device for use in dividing an engine part into sections for rating is provided. The sectioning device has a plurality of sectioners that are slidingly engaged in grooves of two separate plates, held together by at least a fastener. In operation, the sectioners can be adjusted to accommodate engine parts of different sizes, with minimal damages and losses of engine deposits in the rating process.

Abstract: A sectioning device for use in dividing an engine part into sections for rating is provided. The sectioning device has a plurality of sectioners that are slidingly engaged in grooves of two separate plates, held together by at least a fastener. In operation, the sectioners can be adjusted to accommodate engine parts of different sizes, with minimal damages and losses of engine deposits in the rating process.

Abstract: A thermoelectric (TE) device includes a first leg of TE material (a pseudobinary or pseudoternary alloy) and a second leg comprising a metal wire. The second leg is in thermal and electrical communication with the first leg. The TE device has a ZT value of approximately 2.0 at a temperature of approximately 300K.

Abstract: A thermoelectric (TE) device includes a first leg of TE material (a pseudobinary or pseudoternary alloy) and a second leg comprising a metal wire. The second leg is in thermal and electrical communication with the first leg. The TE device has a ZT value of approximately 2.0 at a temperature of approximately 300K.

Abstract: An electro-optic push-pull modulator requiring reduced high switching voltages through combinations of device structure and operation, causing linear and quadratic electro-optic effects to add. Such combinations of device structure and operation include combinations of crystal axis orientation, waveguide structure, electrode structure, electric field biasing, operating wavelengths, and optical polarizations. By inducing linear and quadratic electro-optic effects to add, significant refractive index changes can be realized with lower switching voltages, V&pgr;. Furthermore, significant reduction in switching voltage for push-pull modulators can also be realized through combinations of device structure and operation effectively inducing solely the quadratic electro-optic effect.

Abstract: Quantum-dot superlattice (QLSL) structures having improved thermoelectric properties are described. In one embodiment, PbSexTe1-x/PbTe QDSLs are provided having enhanced values of Seebeck coefficient and thermoelectric figure of merit (ZT) relative to bulk values. The structures can be combined into multi-chip devices to provide additional thermoelectric performance.

Abstract: Quantum-dot superlattice (QLSL) structures having improved thermoelectric properties are described. In one embodiment, PbSexTe1−x/PbTe QDSLs are provided having enhanced values of Seebeck coefficient and thermoelectric figure of merit (ZT) relative to bulk values.

Abstract: An electro-optic push-pull modulator requiring reduced high switching voltages through combinations of device structure and operation, causing linear and quadratic electro-optic effects to add. Such combinations of device structure and operation include combinations of crystal axis orientation, waveguide structure, electrode structure, electric field biasing, operating wavelengths, and optical polarizations. By inducing linear and quadratic electro-optic effects to add, significant refractive index changes can be realized with lower switching voltages, V&pgr;. Furthermore, significant reduction in switching voltage for push-pull modulators can also be realized through combinations of device structure and operation effectively inducing solely the quadratic electro-optic effect.