Abstract: A system for measuring radiation activity of a target radioisotope being produced in a reactor core is disclosed. The system includes a cable assembly and a radiation detector. The cable assembly includes a housing, a target cable configured to position the housing, and a drive cable couplable and decouplable with the target cable. The target radioisotope is positioned within the housing. The drive cable is configured to drive the target cable. The radiation detector configured to periodically measure the radiation activity of the target radioisotope being produced.

Abstract: Disclosed is a method for manufacturing free-standing cladding tubes with multi-layer structures. According to the method, a cylindrical mandrel substrate defining a hollow cylindrical inner space is provided. A first cold spray powder metal is selected. The cylindrical mandrel substrate is rotated and the first cold spray powder metal is applied to an outer surface of the cylindrical mandrel substrate to form a first layer. The cylindrical mandrel substrate is removed.

Abstract: Systems and methods including a material that emits high energy beta particles to destroy cancer cells contained in cancerous tumor or tissue. Electronic neutron generators produce neutrons with energies that have a high probability to interact with the material yttrium-89 to produce yttrium-90. Yttrium-90 emits beta radiation with a maximum energy of about 2.25 MeV and a half-life of about 64 hours, which decays to stable zirconium. Stable yttrium-89 can be directly placed in or around cancerous tissue and irradiated with neutrons in the 0.1-15 KeV energy range to produce significant amounts of yttrium-90. The beta radiation emitted by yttrium-90 will primarily destroy the more radiation sensitive cancer cells within the range of the beta particles. The resulting zirconium isotope is not radioactive such that no further radiation is released. A low probability gamma is also created that will assist in cancer cell destruction.

Abstract: Methods and systems for separation of thorium from uranium and their decay products are provided. The method comprises combining a nuclear fuel feedstock comprising thorium and uranium with a first acid to form a first solution. The first solution is contacted an ion exchange resin that is selective for thorium or uranium. The thorium or uranium is at least partially removed from the first solution by binding the thorium or uranium to the ion exchange resin thereby forming a second solution. The second solution is combined with oxalic acid to precipitate uranium or thorium from the second solution to form a precipitate. The precipitate is separated from the second solution.

Abstract: Provided herein is a method for reducing radiologically-contaminated waste. The method comprises treating radiologically-contaminated surfaces, wherein the radiologically-contaminated surfaces are treated with a surface treatment agent; treating radiologically-contaminated subsurfaces, wherein the radiologically-contaminated subsurfaces are treated with a surface/subsurface treatment agent; consolidating soil waste; employing real-time scanning technology to classify waste, wherein the classifying is based at least in part on a threshold of radiological contamination, and wherein the classified waste is sorted based on the classification; and disposing of the waste via at least one of different disposal routes, based at least in part on the classification.

Abstract: The invention relates to statistical processing of multi-dimensional samples according to a step-wise sequence of iterative tolerance limit definitions using rank statistics. The processing is performed in the context of defining tolerance limits for a population that are compared to multiple process limits or acceptance criteria, with the requirement that a specified fraction of the population be confirmed to fall within the stated acceptance criteria. The symmetry (or asymmetry) may be allocated and controlled by selecting the frequency of occurrence of a specific figure of merit, and its order or position, in the sequential embedding processing sequence.

Abstract: A method for detecting a leak in a cladding tube in a nuclear reactor is described. The method is well-suited for use in a reactor having a plurality of cladding tubes housed in a plurality of linearly arranged channels for flowing coolant past the cladding tubes. The method includes monitoring the channels for the occurrence of an increase in radiation above a selected base line indicative of the presence of at least one fission product in the coolant in at least one of the plurality of channels, and monitoring the channels for the occurrence of time dependent changes in the strength of radiation in the coolant above the base line along the length of the at least one of the plurality of channels. The leak location is calculated by triangulating the radiation readings from a fixed linear array of detectors positioned adjacent to the channels to determine the location of the strongest radiation reading and the location along the length of the channel where the increase in radiation occurred.

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: A heat pipe is disclosed includes a container, a container lid including a groove defined therein, a wick, and an end plug operably coupled to the wick. The end plug includes a pin extending therefrom. The groove of the container lid is configured to receive the pin.

Abstract: A printed circuit heat exchanger for use in a reactor includes a core formed from a stack of plates diffusion bonded together. The core has: a top face, a bottom face disposed opposite the top face, a first side face extending between the top face and the bottom face, and a second side face disposed opposite the first side face. The printed circuit heat exchanger includes: a plurality of primary channels defined in the core, each of the primary channels extending from a primary inlet defined in the first side face to a primary outlet defined in the second side face; and a plurality of secondary channels defined in the core, each of the secondary channels extending among at least some of the primary channels from a secondary inlet defined in the top face to a secondary outlet defined in the top face.

Abstract: A method of forming a water resistant boundary on a fissile material for use in a water cooled nuclear reactor is described. The method comprises mixing a powdered fissile material selected from the group consisting of UN and U3Si2 with an additive selected from oxidation resistant materials having a melting or softening point lower than the sintering temperature of the fissile material, pressing the mixed fissile and additive materials into a pellet, sintering the pellet to a temperature greater than the melting point of the additive. Alternatively, if the melting point of the oxidation resistant particles is greater than the sintering temperature of UN or U3Si2, then the oxidation resistant particles can have a particle size distribution less than that of the UN or U3Si2.

Abstract: A sensor system for a fuel rod including a fuel pellet stack, the sensor system including a wireless interrogator disposed outside the fuel rod and a passive sensor component disposed within the fuel rod. The passive sensor component includes a receiver structured to receive an interrogation signal and output an excitation signal in response to receiving the interrogation signal, a reference transmitter structured to output a reference signal to the reference receiver in response to the excitation signal, a sensing transmitter structured to output a sensing signal to the sensing receiver in response to the excitation signal, and a core at least partially disposed within the sensing transmitter and coupled to move in conjunction with expansion or contraction of the fuel pellet stack, to move based on changes in pressure within the fuel rod, or to change temperature based on temperature changes within the fuel rod.

Abstract: A device that will enable material to be irradiated as needed to produce a desired transmutation product inside the core of a nuclear reactor. The device provides a means for monitoring neutron flux in the vicinity of the material being irradiated to allow determination of the amount of transmutation product being produced. The device enables the irradiated material to be inserted into the reactor and held in place at desired axial positions and to be withdrawn from the reactor when desired without shutting down the reactor. The majority of the device may be re-used for subsequent irradiations. The device also enables the simple and rapid attachment of unirradiated target material to the portion of the device that transmits the motive force to insert and withdraw the target material into and out of the reactor and the rapid detachment or the irradiated material from the device for processing.

Abstract: A base portion for use in a bottom nozzle of a fuel assembly in a nuclear reactor includes a top surface, a bottom surface, and a plurality of vertical wall portions arranged in a generally squared grid-like pattern which extend between the bottom surface and the top surface and which define a plurality of non-circular passages passing between the bottom surface and the top surface through the base portion.

Abstract: A method and apparatus for extending the period a nuclear steam supply system spent fuel pool can be safely passively cooled by storing the spent fuel offloaded from the reactor, in the containment for one reactor operating cycle. During a refueling the spent fuel that is not to be returned to the reactor and the spent fuel that will be returned to the reactor are stored separately in shielded locations within the containment. After one operating cycle, the spent fuel stored within the containment that was not returned to the reactor just prior to the last operating cycle, is offloaded to the spent fuel pool and replaced by the newly offloaded spent fuel that is being retired.

Abstract: A method that provides a more direct indication of peak fuel rod centerline temperature and peak fuel rod clad temperature than conventionally inferred from the power distribution by directly and continuously measuring the fuel temperatures of the fuel pellets in one or more of the hottest fuel elements in the core. The peak fuel rod clad temperature is then obtained from the maximum measured peak fuel rod centerline temperature in combination with the maximum coolant core exit temperature and the minimum coolant flow rate.

Abstract: A plurality of signal anomalies are identified in a number of tubes in a steam generator. Since the geometry of the steam generator is known, the location of each signal anomaly along each tube is converted into a location within the interior of the steam generator. If a plurality of signal anomalies are at locations within the steam generator that are within a predetermined proximity of one another, such a spatial confluence of signal anomalies is determined to correspond with a loose part situated within the steam generator. Additional methodologies can be employed to confirm the existence of the loose part. Historic tube sheet transition signal data can be retrieved and subtracted from present signals in order to enable the system to ignore the relatively strong eddy current sensor signal of a tube sheet which would mask the relatively weak signal from a loose part at the tube sheet transition.

Abstract: A method of determining a core design parameter of a nuclear reactor, includes: calibrating an isolated voltage output from a NIS cabinet associated with the nuclear reactor using a calibrated signal source as an input to the NIS cabinet; recording values of the calibrated signal source used in the calibrating and corresponding values of the output voltage from the calibrating in an as-left cabinet calibration data table; using a computing device connected to the isolated voltage output from the NIS cabinet, converting the voltage output signal to a converted detector signal using at least some of the values in the as-left cabinet calibration data table in an improved signal conversion equation; and using the computing device, employing the converted detector signal to determine the core design parameter.

Abstract: The invention relates to methods for protecting a nuclear reactor core, such as a boiling water reactor core, from fuel and cladding damage due to thermal hydraulic instability in extended operating power flow conditions and, in particular, when an extended power uprate is implemented. The methods employ existing licensed stability methodologies and incorporated minor changes, e.g., to the Average Power Range Monitor (APRM)-based trip system to preclude operation inside the stability vulnerable region of the power/flow map. The APRM-based trip system is modified to set down the APRM flow-biased scram line when core flow is less than a predetermined core flow to prevent the core from entering an unstable region of operation.

Abstract: The invention relates generally to uranium fuel in a nuclear reactor and, more particularly, the inclusion of a fuel additive component to the bulk fuel material. The fuel additive component is selected and provided in an amount such that it is effective to improve one or more properties of the bulk fuel material. The fuel additive component has a grain size that is less than the grain size of the bulk fuel material. The granular fuel additive component coats or covers the granular bulk fuel material.