Abstract: Systems for producing hydrogen gas for local distribution, consumption, and/or storage, and related devices and methods are disclosed herein. A representative system includes a pyrolysis reactor that can be coupled to a supply of reaction material that includes a hydrocarbon. The reactor includes one or more flow channels positioned to transfer heat to the reaction material to convert the hydrocarbon into an output that includes hydrogen gas and carbon particulates. The system also includes a carbon separation system operably coupled to the pyrolysis reactor to separate the hydrogen gas the carbon particulates in the output. In various embodiments, the system also includes components to locally consume the filtered hydrogen gas.

Abstract: Systems for producing hydrogen gas for local distribution, consumption, and/or storage, and related devices and methods are disclosed herein. A representative system includes a pyrolysis reactor that can be coupled to a supply of reaction material that includes a hydrocarbon. The reactor includes one or more flow channels positioned to transfer heat to the reaction material to convert the hydrocarbon into an output that includes hydrogen gas and carbon particulates. The system also includes a carbon separation system operably coupled to the pyrolysis reactor to separate the hydrogen gas the carbon particulates in the output. In various embodiments, the system also includes components to locally consume the filtered hydrogen gas.

Abstract: Embodiments disclosed herein relate to a garment system including at least one sensor and at least one actuator that operates responsive to sensing feedback from the at least one sensor to cause a flexible compression garment to selectively constrict or selectively dilate, thereby compressing or relieving compression against at least one body part of a subject. Such selective constriction or dilation can improve muscle functioning or joint functioning during use of motion-conducive equipment, such as an exercise bike or rowing machine.

Abstract: Various disclosed embodiments include thermionic energy converters with a thermal concentrating hot shell and emitters for thermionic energy converters. In some embodiments, an illustrative thermionic energy converter includes: an emitter electrode; a hot shell configured to concentrate heat flow toward the emitter electrode; a collector electrode; and a cold shell that is thermally isolated from the hot shell.

Abstract: Combined combustion and pyrolysis (CCP) systems, and associated systems and methods, are disclosed herein. In some embodiments, the CCP system includes an input valve fluidly coupleable to a fuel supply to receive a hydrocarbon reactant, a CCP reactor fluidly coupled to the input valve, and a carbon separation component fluidly coupled to the CCP reactor. The CCP reactor can include a combustion chamber, a reaction chamber in thermal communication with the combustion chamber and/or fluidly coupled to the input valve, and an insulating material positioned to reduce heat loss from the combustion chamber and/or the reaction chamber. The CCP reactor can also include a combustion component positioned to combust a fuel within the combustion chamber. The combustion can heat the reaction chamber and the hydrocarbon reactant flowing therethrough. The heat causes a pyrolysis of the hydrocarbon reactant that generates hydrogen gas and carbon.

Abstract: Systems for producing hydrogen gas for local distribution, consumption, and/or storage, and related devices and methods are disclosed herein. A representative system includes a pyrolysis reactor system that can be coupled to a supply of reaction material that includes a hydrocarbon. The pyrolysis reactor system includes one or more combustion components positioned to transfer heat to the reaction material to convert the hydrocarbon into an output that includes hydrogen gas and carbon particulates. The pyrolysis reactor system also includes a carbon separation system positioned to separate the hydrogen gas the carbon particulates in the output. In various embodiments, the system also includes components to locally consume the filtered hydrogen gas, such as a power generator, heating appliance, and/or a combined heat and power device.

Abstract: Combined heat and power (CHP) systems and related methods are disclosed herein. In some embodiments, the CHP system includes a combustion component and a power cell operably coupled to the combustion component. The power cell can include a first heat exchanger thermally coupled to the combustion component to receive heat; a second heat exchanger; and an electricity generation component with a first portion thermally coupled to the first heat exchanger and a second portion thermally coupled to the second heat exchanger. The electricity generation component is positioned to receive at least a portion of the heat received at the first heat exchanger and generate an electrical output using the received heat. To recycle unused heat from the power cell, the second heat exchanger can be thermally coupleable to a third heat exchanger in a residential heating appliance.

Abstract: Disclosed embodiments include vacuum electronic devices, methods of operating a vacuum electronic device, and methods of fabricating a vacuum electronic device. In a non-limiting embodiment, a vacuum electronics device includes a cathode and an anode. At least one focus grid is disposed between the cathode and the anode, and the at least one focus grid is physically disconnected from the cathode. The at least one acceleration grid is disposed between the cathode and the anode, and the at least one acceleration grid is further disposed adjacent the at least one focus grid. The at least one acceleration grid is physically disconnected from the cathode.

Abstract: Systems for producing hydrogen gas for local distribution, consumption, and/or storage, and related devices and methods are disclosed herein. A representative system includes a pyrolysis reactor that can be coupled to a supply of reaction material that includes a hydrocarbon. The reactor includes one or more flow channels positioned to transfer heat to the reaction material to convert the hydrocarbon into an output that includes hydrogen gas and carbon particulates. The system also includes a carbon separation system operably coupled to the pyrolysis reactor to separate the hydrogen gas the carbon particulates in the output. In various embodiments, the system also includes components to locally consume the filtered hydrogen gas.

Abstract: Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one alkali metal thermal-to-electricity converter (AMTEC) has a high pressure zone and a low pressure zone, the high pressure zone being thermally couplable to the at least one burner, the low pressure zone being thermally couplable to the heat exchanger.

Abstract: Disclosed embodiments include conductive oxide-coated electrodes and methods of fabricating a conductive oxide-coated electrode. In a non-limiting embodiment, a conductive oxide-coated electrode includes: a conductive layer; and an oxide coating disposed on the conductive layer. In another non-limiting embodiment, a method of fabricating a conductive oxide-coated electrode includes: patterning a conductive layer; etching the patterned conductive layer; and disposing an oxide coating on the etched conductive layer.

Abstract: Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one thermophotovoltaic converter has a photon emitter and at least one photovoltaic cell, the photon emitter being thermally couplable to the at least one burner, the at least one photovoltaic cell being thermally couplable to the heat exchanger.

Abstract: Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one thermophotovoltaic converter has a photon emitter and at least one photovoltaic cell, the photon emitter being thermally couplable to the at least one burner, the at least one photovoltaic cell being thermally couplable to the heat exchanger.

Abstract: Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one alkali metal thermal-to-electricity converter (AMTEC) has a high pressure zone and a low pressure zone, the high pressure zone being thermally couplable to the at least one burner, the low pressure zone being thermally couplable to the heat exchanger.

Abstract: Various disclosed embodiments include elements for mitigating electron reflection in a vacuum electronic device, vacuum electronic devices that incorporate elements for mitigating electron reflection, and methods of fabricating elements for reducing reflection of electrons off an electrode. An illustrative electrode assembly includes an electrode. Elements are configured to reduce reflection of electrons off the electrode.

Abstract: Various disclosed embodiments include thermionic energy converters with a thermal concentrating hot shell and emitters for thermionic energy converters. In some embodiments, an illustrative thermionic energy converter includes: an emitter electrode; a hot shell configured to concentrate heat flow toward the emitter electrode; a collector electrode; and a cold shell that is thermally isolated from the hot shell.

Abstract: Disclosed embodiments include vacuum electronic devices and methods of fabricating a vacuum electronic device. In a non-limiting embodiment, a vacuum electronic device includes an electrode that defines discrete support structures therein. A first film layer is disposed on the electrode about a periphery of the electrode and on the support structures. A second film layer is disposed on the first film layer. The second film layer includes electrically conductive grid lines patterned therein that are supported by and suspended between the support structures.

Abstract: Embodiments disclosed herein relate to a garment system including at least one sensor and at least one actuator that operates responsive to sensing feedback from the at least one sensor to cause a flexible compression garment to selectively constrict or selectively dilate, thereby compressing or relieving compression against at least one body part of a subject. Such selective constriction or dilation can improve muscle functioning or joint functioning during use of motion-conducive equipment, such as an exercise bike or rowing machine.

Abstract: Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one thermionic energy converter has a hot shell and a cold shell, the hot shell being thermally couplable to the at least one burner, the cold shell being thermally couplable to the heat exchanger.

Abstract: Various disclosed embodiments include combined heating and power modules and combined heat and power devices. In an illustrative embodiment, a combined heat and power device includes a heating system including: at least one burner; at least one igniter configured to ignite the at least one burner; a fluid motivator assembly including an electrically powered prime mover; and a heat exchanger fluidly couplable to the fluid motivator assembly. At least one thermionic energy converter has a hot shell and a cold shell, the hot shell being thermally couplable to the at least one burner, the cold shell being thermally couplable to the heat exchanger.