Abstract: In a panel that uses the gamma radiation emitted by fission to produce electrical power, a source of an electrical current is connected to a layer of the panel made of a metal with a relatively high atomic number (Z) that forms an electron emitter. The emitter layer is surrounded by an insulation layer which in turn is surrounded by a relatively low Z value layer for collecting electrons from the emitter. Another layer of insulation and an outer sheath surround the collector. The improved panel may be used for reactor power level and power distribution measurements, and for initiating, maintaining or returning molten salt or metal coolants in the liquid state.

Abstract: A seismic isolation apparatus 1 includes a laminated body 7 having alternately laminated a plurality of elastic layers 2 and rigid layers 3, and a lead plug 17 being disposed therein without clearances in a hollow portion 14 extending in a laminated direction V of the laminated body 7 with respect to inner peripheral surfaces 15 of the elastic layers 2, inner peripheral surfaces 16 of the rigid layers 3, a lower surface 12 of an upper plate 10, and an upper surface 13 of a lower plate 11.

Abstract: A method and system for the thermoelectric conversion of nuclear reactor generated heat including upon a nuclear reactor system shutdown event, thermoelectrically converting nuclear reactor generated heat to electrical energy and supplying the electrical energy to a mechanical pump of the nuclear reactor system.

Abstract: An apparatus, system and method provides electrical power in a subterranean well. A radioisotope thermoelectric generator may be positioned and installed in a downhole location in a wellbore. The location of the radioisotope thermoelectric generator may be within a completion string. A radioisotope thermoelectric generator comprises a core having a radioisotope for producing heat, and a thermocouple. The thermocouple comprises at least two different metals, and is positioned adjacent to the core. The radioisotope thermoelectric generator flows heat from the core to the thermocouple to produce electricity that may be stored in an energy storage device, or used to power a component. The produced electrical power may be employed to activate downhole sensors, valves, or wireless transmitters associated with the operation and production of an oil or gas well.

Abstract: A system and method are provided for generating electric power from relatively low temperature energy sources at efficiency levels not previously available. The present system and method employ recent advances in low energy nuclear reaction technology and thermionic/thermotunneling device technology first to generate heat and then to convert a substantial portion of the heat generated to usable electrical power. Heat may be generated by a LENR system employing nuclear reactions that occur in readily available materials at ambient temperatures without a high energy input requirement and do not produce radioactive byproducts. The heat generated by the LENR system may be transferred through one or more thermionic converter devices in heat transfer relationship with the LENR system to generate electric power.

Abstract: A thermionic electric converter includes a cathode output enhancing laser (374) operable to direct a laser beam (376) to strike an emissive surface of a cathode emitter (321), to increase the electron output of the cathode emitter (321). The cathode output enhancing lase (374) is positioned to direct a laser beam (375) through an opening (370) in the anode (306) or target structure, in the direction of the cathode emitter (321). An electron repulsion ring (380) is provided at an edge of the opening (370) in the anode (306), to reduce the number of electrons missing the anode (306) and passing through the opening (370) in the anode (306).

Abstract: A multiple cell thermionic converter having a generally tubular member of electrically conductive refractory metal with an internal cavity and a tubular envelope of electrically conductive refractory metal disposed in surrounding relationship to such generally tubular member. Electrically insulating ceramic material is disposed upon sections of facing surfaces of the envelope and tubular member, which is in the form of a body that has a central zone of plasma-sprayed refractory metal oxide selected from the group consisting of scandia, hafnia, zirconia and alumina, and a pair of flanking outer zones made of mixtures of the refractory oxide and particulate refractory metal. Refractory metal electron emitters and collectors are supported upon the ceramic bodies and juxtaposed in pairs with an annular gap therebetween to form a plurality of thermionic cells.

Abstract: A device for generating direct current by neutron activation of a plurality of series-connected beta-emitter (nuclear decay electron) cells, located in the out-of-core region of a light water nuclear reactor. The device can be used as either a current source, or preferably configured as a DC voltage source, capable of powering low-power, radiation-hardened, high-temperature integrated circuitry contained in the reactor vessel. As such, the device acts like a DC battery that is activated by (n, .gamma.) reactions, both thermal and epithermal (by resonance capture). The device is not operable until exposed to a substantial neutron flux, so it has unlimited shelf-life and is not radioactive during manufacture In the preferred embodiment, an isotope of the metallic rare-earth element dysprosium is configured in a "sandwich" geometry to generate sufficient current that a useful steady voltage can be generated by means of a simple voltage regulation circuit.

Abstract: A stand-alone low-voltage direct current power supply, for use as a battery, which is energized by the decay of a radioactive isotope in response to neutron capture. During this decay, either .alpha.- or .beta.-particles are emitted. The emitting radioactive isotope should have adequate half-life and no .gamma.-emission. The preferred .beta.-emitting radioisotope is thallium, which decays directly to the ground state of Pb.sup.204 by 763-keV .beta.-decay with no .gamma.-emission. The resulting .beta.-particles are collected to form a current which can be used for various purposes inside a reactor. The preferred .alpha.-emitting radioisotope is americium.

Abstract: The apparatus is a combined Alkali Metal Thermal to Electric Converter (AMTEC) and a thermionic energy converter which are mated by the use of a common heat transfer device which can be a heat pipe, pumped fluid or a simple heat conduction path. By adjusting the heat output surface area of the thermionic converter and the heat input surface area of the AMTEC, the heat transfer device accomplishes not only the transfer of heat from the output of the thermionic converter to the input of the AMTEC, but also the transformation of the heat density to match the requirements of the AMTEC input. The electrical current through the combined devices is also matched by adjusting the heated surface area of the AMTEC.

Abstract: A hydrogenous moderated thermionic nuclear reactor operating in the thermal neutron energy region. Thermionic fuel elements are formed from multiple concentric cylinders. The center cylinder is a combination heat pipe and thermionic converter collector. The second cylinder is the converter emitter. The third cylinder is the nuclear fuel. The outer cylinder is the physical barrier between the fuel element and moderator. Between the outer radius of the fuel and outer cylinder is a gap containing multi-foil insulation. The insulation acts as a thermal barrier between the fuel and the outer cylinder and accommodates fuel expansion. This also causes heat flow to be radially inward from the fuel to the center converter/heat pipe.

Abstract: A plasma thermoelement which is built into the immediate volume of a nuclear fuel mass of a nuclear fuel element is described which comprises a snorkel (12) which is surrounded by a nuclear fuel mass (14) which in turn is surrounded by a cladding (16). Both the exit end of the snorkel and the cladding are connected electrically only via an external load. The nuclear fuel mass is formed from a multitude of the ceramic nuclear fuel microspheres (24). The use of plasma as high-temperature conductor of thermoelement permits to increase conversion efficiency and decrease mass of conversion system.

Abstract: By using the helium generated by the alpha emissions of a thermoelectric generator during space travel for cooling, the thermal degradation of the thermoelectric generator can be slowed. Slowing degradation allows missions to be longer with little additional expense or payload.

Abstract: A thermionic reactor for providing electrical power and propulsion power. A reactor vessel has a plurality of thermionic heat pipe modules located therein and spaced apart on a hexagonal pitch. Nuclear fuel elements are positioned in the spaces between the thermionic heat pipe modules. Insulating material is provided between the reactor vessel and the array of thermionic heat pipe modules and nuclear fuel elements. Propulsion power is provided by a propellant storage tank and propellant nozzle in fluid communication with opposite ends of the reactor vessel. The thermionic heat pipe modules serve to produce electricity and aid in removal of waste heat.

Abstract: A thermionic electric converter module integrated with heating and cooling heat pipes. Two heat pipes are arranged concentrically, with the annular emitter heat pipe on the outside of the module to isothermally distribute heat from a source located in any direction around the unit to the emitter located on the inside exterior wall of the heat pipe. The exterior wall surface of the collector heat pipe, located inside the annular emitter heat pipe, is separated from the emitter by the thermionic converter's interelectrode gap and serves as the collector of the thermionic converter. The collector heat pipe is of conventional cylindrical configuration and transports the waste heat of the thermionic converter along the unit's axis to a remote location for disposal.

Abstract: An improvement is set forth in a thermionic fuel element which includes a collector base supporting a collector adjacent and closely spaced from an emitter which is supported by an emitter base, the emitter base being adapted to be heated by a heat source. In accordance with the invention a thermal shield structure is located between a portion of the emitter and the collector. The shield structure insulates that portion of the collector opposite the shield structure from receiving at least a portion of the radiation developed by the heat source.

Abstract: An apparatus for protecting personnel and the environment from harmful emissions of radiation from a source thereof includes a plurality of shielding parts so located as to be in the path of the radioactive emissions and to absorb them (one such part being located farther away from the source of emissions than the other) so that an electrical potential difference between the shielding parts is established, due to different absorptions of radiation by them, means for consuming electrical power at a location remote from the radioactive source, and electrical conductors communicating the consuming means (or load) with such shielding parts. Although the invention is primarily intended for protecting personnel and the environment against emissions from radiation sources, such as radioactive wastes, it is also useful for shielding other sources of harmful radiated emissions. Also within the invention are processes for protecting personnel and the environment against radiation hazards.

Abstract: A radiation gradient is utilized to transform harmful radiant energy into safer, more useful forms, thus collecting, controlling and consuming the energies of radiant emissions and protecting the environment and living organisms from them. More specifically, there is disclosed a new process for shielding emitters of harmful radiation by establishing an electrical circuit, which process includes shielding the source of radiation while collecting the energy of relatively more radiation on an electrically conductive material and collecting the energy of relatively less radiation on other electrically conductive material, which may include a ground or external sink, thus establishing a difference in electrical potential, and transferring this potential difference, along with any potential difference from auxiliary devices, outside the shielded area, to resistors and/or variable other loads, which consume the voltage as it is created.

Abstract: A pressure vessel for nuclear energy powered thermionic fuel elements is disclosed. An inner cylindrical nuclear fuel heat source is surrounded by cylindrical layers of, in outward order, an emitter, a gap, a collector, an insulator and a cladding layer. A hexagonal pressure vessel surrounds the other parts of the thermionic fuel element and forms liquid metal coolant passages between the inside corners of the hexagon and the cladding. Longitudinally, each thermionic fuel element comprises a middle active zone between two 20% enriched uranium zones to reduce the critical mass of the system for safety. Beryllium zone endcaps act as neutron reflectors and further reduce the critical mass. A plurality of thermionic fuel elements is arrayed into a reactor core with brazed together pressure vessel hexagon sides. In the event of a leak, or other coolant flow failure, the pressure vessel sides act as thermal conduction fins and transfer waste heat to adjacent pressure vessels where coolant flow has not failed.

Abstract: A support is provided for use in a therminonic converter to support an end of an emitter to keep it out of contact with a surrounding collector while allowing the emitter end to move axially as its temperature changes. The emitter end (34) is supported by a spring structure (44) that includes a pair of Belleville springs, and the spring structure is supported by a support structure (42) fixed to the housing that includes the collector. The support structure is in the form of a sandwich with a small metal spring-engaging element (74) at the front end, a larger metal main support (76) at the rear end that is attached to the housing, and with a ceramic layer (80) between them that is bonded by hot isostatic pressing to the metal element and metal main support. The spring structure can include a loose wafer (120) captured between the Belleville springs.

Abstract: A self-actuating reactor shutdown system incorporating a thermionic switched electromagnetic latch arrangement which is responsive to reactor neutron flux changes and to reactor coolant temperature changes. The system is self-actuating in that the sensing thermionic device acts directly to release (scram) the control rod (absorber) without reference or signal from the main reactor plant protective and control systems.To be responsive to both temperature and neutron flux effects, two detectors are used, one responsive to reactor coolant temperatures, and the other responsive to reactor neutron flux increase. The detectors are incorporated into a thermionic diode connected electrically with an electromagnetic mechanism which under normal reactor operating conditions holds the the control rod in its ready position (exterior of the reactor core).

Abstract: A control system for the automatic or self-actuated shutdown or "scram" of a nuclear reactor. The system is capable of initiating scram insertion by a signal from the plant protection system or by independent action directly sensing reactor conditions of low-flow or over-power.Self-actuation due to a loss of reactor coolant flow results from a decrease of pressure differential between the upper and lower ends of an absorber element. When the force due to this differential falls below the weight of the element, the element will fall by gravitational force to scram the reactor.Self-actuation due to high neutron flux is accomplished via a valve controlled by an electromagnet and a thermionic diode. In a reactor over-power, the diode will be heated to a change of state causing the electromagnet to be shorted thereby actuating the valve which provides the changed flow and pressure conditions required for scramming the absorber element.

Abstract: A thermionic energy conversion system assembly is described which comprises a fissionable nuclear fuel which surrounds a cylindrical arrangement of thermionic emitter electrodes which surround corresponding collector electrodes, which in turn surround a cylindrical container of a heat sink material, such as lithium hydride, which can absorb large amounts of waste heat energy through a phase change. The heat sink material may also act as a nuclear moderator to reduce the amount of required nuclear fuel. A heat pipe is enclosed within the container of heat sink material to remove waste heat stored in the material. A thermionic energy conversion module is described which comprises 100 stacked-in-series thermionic converter assemblies. A complete space-based thermionic nuclear reactor is described which comprises an array of 91 thermionic converter modules wherein the heat pipes connect to a lithium hydride radiation shield which acts as a further heat sink.

Abstract: A thermally actuated thermionic switch which responds to an increase of temperature by changing from a high impedance to a low impedance at a predictable temperature set point. The switch has a bistable operation mode switching only on temperature increases. The thermionic material may be a metal which is liquid at the desired operation temperature and held in matrix in a graphite block reservoir, and which changes state (ionizes, for example) so as to be electrically conductive at a desired temperature.

Abstract: A laser using heat and thermionic electrical output from a nuclear reactor in which heat generated by the reactor is utilized to vaporize metal lasants. Voltage output from a thermionic converter is used to create an electric discharge in the metal vapors. In one embodiment the laser vapors are excited by a discharge only. The second embodiment utilizes fission coatings on the inside of heat pipes, in which fission fragment excitation and ionization is employed in addition to a discharge. Both embodiments provide efficient laser systems that are capable of many years of operation without servicing. Metal excimers are the most efficient electronic transition lasers known with output in the visible wavelengths. Use of metal excimers, in addition to their efficiency and wavelengths, allows utilization of reactor waste heat which plagues many nuclear pumped laser concepts.