Abstract: A method for assaying a wall of a pressure tube for a nuclear reactor is disclosed. The wall has a matrix material and deuterium nuclei in the matrix material. The method includes: (a) transmitting gamma rays into the matrix material to induce photodisintegration of at least some of the deuterium nuclei, whereby reaction particles of the nuclei are emitted from the wall; (b) detecting at least some of the reaction particles emitted in step (a) using a particle detector; and (c) generating particle signals in response to detecting the particles in step (b).

Abstract: A mitigation assembly for a nuclear reactor including a box with an upper portion forming the head of the assembly housing an upper neutron shielding device, including a head including removable lock and a slug installed free to move in translation relative over a given travel distance, the lock being configured such that locking/unlocking between the head and the box can be made by displacement of the slug with an extraction grab with its pawls attached in the slug. The lower part of the upper neutron shielding device includes a cone-shaped sealing block with the tip of the cone oriented downwards, cooperating with a cone-shaped internal surface of the box, a sealing device being formed between the two, the assembly created forming a removable sealing plug.

Abstract: The invention relates to a method for eliminating neutrons from fission, fusion or aneutronic nuclear reactions in a reactor (100), in particular in a laser-driven nuclear fusion reactor (100) which operates with hydrogen and the boron-11 isotope, in which method at least some moderated neutrons are made to undergo a nuclear reaction with tin (11). As a result of the nuclear reactions with tin, the neutrons convert the tin nuclei into stable nuclei having a higher atomic weight resulting from neutron capture. The invention also relates to a reactor (100) which is designed for energy conversion by means of fission, fusion or aneutronic nuclear reactions and for generating electric energy, wherein the reactor contains a neutron elimination device (50) which contains tin and is arranged such that at least some moderated neutrons are made to undergo a nuclear reaction with the tin.

Abstract: A container for storing and/or transporting spent nuclear fuel. The container includes a body that defines an internal cavity that holds the spent nuclear fuel and an outer surface. The outer surface has holes formed therein into which trunnions are positioned. The container can be lifted by a lift yoke by coupling the lift yoke to the trunnions. The trunnions may include first and second components such that the first component is slidable in its axial direction relative to the second component when a force that exceeds a threshold acts on the second component. Thus, the second component may be slidable between a protruded state in which a portion of the second component protrudes from the outer surface of the body and a retracted state in which the second component does not protrude from the outer surface of the body.

Abstract: A nuclear reactor is positioned on a barge which is floating in a water tank. A plurality of counter weight assemblies interconnect the barge with the tank to create a lifting force to the barge and to maintain the barge in a level position. Structure is also included for limiting horizontal movement of the counter weight of the counter weight assemblies.

Abstract: A channel type heterogeneous reactor core for a heavy water reactor for burnup of thorium based fuel is provided. The heterogeneous reactor core comprises at least one seed fuel channel region comprising seed fuel channels for receiving seed fuel bundles of thorium based fuel; and at least one blanket fuel channel region comprising blanket fuel channels for receiving blanket fuel bundles of thorium based fuel; wherein the seed fuel bundles have a higher percentage content of fissile fuel than the blanket fuel bundles. The seed fuel channel region and the blanket fuel channel region may be set out in a checkerboard pattern or an annular pattern within the heterogeneous reactor core. Fuel bundles for the core are also provided.

Abstract: An apparatus having a nuclear reactor comprising a pressure vessel containing primary coolant water and further containing a nuclear reactor core comprising fissile material, a mounting/electrical distribution plate secured entirely within the pressure vessel and configured to be submerged in the primary coolant, a set of control rod drive mechanism (CRDM) units mounted directly on the mounting/electrical distribution plate, and a plurality of cable modules mounted in receptacles of the mounting/electrical distribution plate wherein each cable module includes mineral insulated (MI) cables connected with one or more of the CRDM units, the cable module including its MI cables being removable as a unit from the receptacle of the mounting/electrical distribution plate.

Abstract: A channel type heterogeneous reactor core for a heavy water reactor for burnup of thorium based fuel is provided. The heterogeneous reactor core comprises at least one seed fuel channel region comprising seed fuel channels for receiving seed fuel bundles of thorium based fuel; and at least one blanket fuel channel region comprising blanket fuel channels for receiving blanket fuel bundles of thorium based fuel; wherein the seed fuel bundles have a higher percentage content of fissile fuel than the blanket fuel bundles. The seed fuel channel region and the blanket fuel channel region may be set out in a checkerboard pattern or an annular pattern within the heterogeneous reactor core. Fuel bundles for the core are also provided.

Abstract: Method and apparatus for heating and/or compressing plasmas to thermonuclear temperatures and densities are provided. In one aspect, at least one of at least two plasmoids separated by a distance is accelerated towards the other. The plasmoids interact, for instance to form a resultant plasmoid, to convert a kinetic energy into a thermal energy. The resultant plasmoid is confined in a high energy density state using a magnetic field. One or more plasmoids may be compressed. Energy may be recovered, for example via a blanket and/or directly via one or more coils that create a magnetic field and/or circuits that control the coils.

Abstract: A target unit for producing Cu67 radioisotope is described herein, and comprises a cage body releasably coupled to a screw-on cap; and a ceramic capsule containing a solid Zn68 target ingot and having one open end and one closed end and defining an interior chamber for the target ingot. The ceramic capsule is releasably contained between the cage body and the screw-on cap with a lid disposed on the open end of the capsule and a washer positioned between the lid and the screw-on cap. The screw-on cap and the washer provide a water-tight seal between the lid and the capsule. The interior of the capsule is in intimate physical contact with the target ingot; and the Zn68 of the target ingot is free of traces of residual oxygen that interfere with contact of the Zn68 to the capsule.

Abstract: A method for heating primary coolant in a nuclear supply system in one embodiment includes filling a primary coolant loop within a reactor vessel and a steam generating vessel that are fluidly coupled together with a primary coolant, drawing a portion of the primary coolant from the primary coolant loop and into a start-up sub-system, heating the portion of the primary coolant to form a heated portion of the primary coolant, and injecting the heated portion of the primary coolant back into the primary coolant loop. The primary coolant may be heated to a no-load operating temperature.

Abstract: A fuel assembly inspection system that utilizes a pressure transducer mounted to a utility's spent fuel handling tool to detect a relative change in depth of a fuel assembly during fuel inspections. The system then wirelessly transmits the signal to a fuel inspection recording system, which converts the signal to a relative height along the fuel assembly being viewed by a camera, and displays the relative height along with the applicable fuel assembly feature being viewed by the camera (e.g., nozzle, grid, span) via a text overlay on the video image of the inspection.

Abstract: Apparatuses and methods for producing neutrons for applications such as boron neutron capture therapy (BNCT) are described. An apparatus can include a rotary fixture with a coolant inlet and a coolant outlet, and a plurality of neutron-producing segments. Each neutron-producing segment of the plurality of neutron-producing segments is removably coupled to the rotary fixture, and includes a substrate having a coolant channel circuit defined therein and a solid neutron source layer disposed thereon. The coolant channel circuits are in fluid communication with the coolant inlet and the coolant outlet.

Abstract: According to one embodiment, a method for producing a directed neutron beam includes producing a voltage of negative polarity of at least ?100 keV on a surface of a deuterated or tritiated target in response to a temperature change of a pyroelectric crystal of less than about 40° C., the pyroelectric crystal having the deuterated or tritiated target coupled thereto, pulsing a deuterium ion source to produce a deuterium ion beam, accelerating the deuterium ion beam to the deuterated or tritiated target to produce a neutron beam, and directing the ion beam onto the deuterated or tritiated target to make neutrons using at least one of a voltage of the pyroelectric crystal, and a high gradient insulator (HGI) surrounding the pyroelectric crystal. The directionality of the neutron beam is controlled by changing the accelerating voltage of the system. Other methods are presented as well.

Abstract: A nuclear reactor core comprising fissile material is surrounded by a core former. The core former comprises one or more single-piece annular rings wherein each single-piece annular ring comprises neutron-reflecting material. In some embodiments the core former comprises a stack of two or more such single-piece annular rings. In some embodiments the stack of single-piece annular rings is self-supporting. In some embodiments the stack of single-piece annular rings does not include welds or fasteners securing adjacent single-piece annular rings together. A core basket may contain the nuclear reactor core and the core former, and in some embodiments an annular gap is defined between the core former and the core basket. In some embodiments the core former does not include welds and does not include fasteners.

Abstract: According to an embodiment, an emergency core cooling system has: three active safety divisions each including only one motor-driven active safety system; one passive safety division including a passive safety system; an emergency power source disposed in each of the active safety divisions to supply electric power to the motor-driven active safety system; and an advanced passive containment cooling system disposed in the passive safety division. Only two active safety divisions each includes a low pressure flooder system that is commonly used with a residual heat removal system as the only one motor-driven active safety system. The other active safety division includes an air-cooled injection system as the only one motor-driven active safety system.

Abstract: A system and method for consolidating used nuclear fuel rods using tools operably suspendable in a recess containing the used nuclear fuel rods. The systems and methods safely consolidate the used nuclear fuel rods in containers.

Abstract: A method including providing an internal control rod drive mechanism (CRDM) including an electric motor and a support surface including sealed electrical connectors electrically connected with the electric motor to deliver electrical power to the electrical motor, installing the internal CRDM inside a nuclear reactor, the installing including placing the support surface of the internal CRDM onto a support element inside the nuclear reactor, the placing causing sealed electrical connectors disposed on the support element to mate with the sealed electrical connectors on the support surface of the internal CRDM, wherein the nuclear reactor contains coolant water and the installing is performed with the internal CRDM submerged in the coolant water and the seals of the sealed electrical connectors of the internal CRDM and the support element are effective to prevent coolant water ingress into the sealed electrical connectors.

Abstract: The invention relates to a nuclear power plant including a containment vessel including a reactor pressure vessel for receiving fissionable nuclear fuel, an aerosol filter stage a pressure relief conduit through which a gas volume flow which is filtered in the aerosol filter stage is releasable to ambient through a pass through opening in the containment vessel, and an iodine filter stage through which the gas volume flow that is filtered in the aerosol filter stage is filterable before being released to the ambient, wherein the iodine filter stage is arranged within the containment vessel, characterized in that the aerosol filter stage and the iodine filter stage are connected with one another so that transferring the gas volume flow from the aerosol filter stage to the iodine filter stage is performed essentially at an identical pressure level.

Abstract: Cores include different types of control cells in different numbers and positions. A periphery of the core just inside the perimeter may have higher reactivity fuel in outer control cells, and lower reactivity cells may be placed in an inner core inside the inner ring. Cores can include about half fresh fuel positioned in higher proportions in the inner ring and away from inner control cells. Cores are compatible with multiple core control cell setups, including BWRs, ESBWRs, ABWRs, etc. Cores can be loaded during conventional outages. Cores can be operated with control elements in only the inner ring control cells for reactivity adjustment. Control elements in outer control cells need be moved only at sequence exchanges. Near end of cycle, reactivity in the core may be controlled with inner control cells alone, and control elements in outer control cells can be fully withdrawn.