Abstract: A pressure-tube nuclear reactor can include an outer shell having an interior to contain a moderator at a first pressure and a coolant plenum to receive the coolant fluid at a second pressure, the second pressure being greater than the first pressure. The reactor also includes a plurality of pressure tubes. Each pressure tube is received within and extends through a corresponding shell tube and is configured to releasably retain at least one fuel bundle. A first end of each pressure tube being coupled to the plenum tubesheet in fluid communication with the plenum chamber and a second end of each pressure tube fluidly connected to a coolant conduit to enable the coolant fluid to flow between the coolant plenum and each pressure tube and to flow from the nuclear reactor for further processing.

Abstract: An annulus spacer for a fuel channel assembly of a nuclear reactor. The fuel channel assembly includes a calandria tube and a pressure tube positioned at least partially within the calandria tube. The annulus spacer includes a garter spring configured to surround a portion of the pressure tube to maintain a gap between the calandria tube and the pressure tube. The garter spring includes a first end and a second end. The annulus spacer also includes a connector coupled to the first end and the second end of the garter spring. The connector allows movement of the annulus spacer when the pressure tube moves relative to the calandria tube during thermal cycles of the fuel channel assembly. The annulus spacer further includes a girdle wire positioned substantially within the garter spring and configured to form a loop around the pressure tube.

Abstract: The present invention provides a replication device for delivering a replicating material to a surface. The device includes an extrusion piston slidably received therein and movable to a dispensing position for expelling the replicating material though an outlet. The device further includes an actuator, wherein the actuator produces stress waves so as to temporarily reduce the viscosity of the material during delivery of said material. Also provided is a method and kit for using the device for obtaining a replica of a surface.

Abstract: The invention relates to isotope separation methods, and methods for separating isotopes with low energy consumption, demonstrated using hydrogen isotopes. To this end, an isotope transfer electrochemical cell is provided, which comprises an anode plate and a cathode plate; current carrier plates with flow channels or mesh layers or porous material; a proton exchange membrane or solid polymer electrolyte membrane; and gas diffusion layers positioned on either side of the proton exchange membrane which together with the proton exchange membrane forms a membrane electrode assembly; and a housing containing the anode and cathode plates in operable arrangement with the membrane electrode assembly, and defining a hydrogen feed inlet on the anode, a product outlet on the cathode, an outlet for excess hydrogen on the anode, and internal flow paths for transfer of gases and fluids on either side of the membrane electrode assembly.

Abstract: A method for preparing alpha sources of polonium. A sample of polonium is provided in a solution. A controlled amount of sulfide and a controlled amount of a metal capable of forming an insoluble sulfide salt in the solution are introduced into the solution, in order to co-precipitate polonium from the solution. The precipitates are filtered out.

Abstract: To avoid the detrimental effects of bubbles in the carrying out of immersion ultrasonic testing, various surfaces may be coated with a coating that includes appropriately selected compounds. Such compounds may include those compounds that cause higher local surface tension and those compounds that are hydrophilic. Furthermore, various surfaces involved in the testing may be coated in a manner that minimizes cavities and crevices to which air bubbles can adhere.

Abstract: A method of measuring ionizing radiation may include the steps of: a) creating charged particles; b) causing the charged particles to generate the electrons; c) collecting at least a portion of the multiplied free electrons using at least two anode pads provided within the chamber, each anode pad producing a corresponding anode output signal, to provide higher sensitivity; and d) recording each anode output signal.

Abstract: A tool may be inserted into the pressure tube inside a calandria tube of a fuel channel of a nuclear reactor. Once in position, the tool may act to generate information useful for determining a location for an annulus spacer. Once the annulus spacer has been located, the tool may act to generate information useful for determining a compressive load on the annulus spacer due to the annulus spacer being pinched between the two tubes. In both the locating and the load determining, the tool may act to isolate a section of the pressure tube, excite the isolated section of the pressure tube with vibrations and measure resultant tube vibrations. Tube vibration characteristics, determined from the vibrations, may then be analyzed to determine an axial location along the pressure tube for the annulus spacer and/or determine a load on the annulus spacer.

Abstract: A system for determining a radiation dose in real time can include at least one three-dimensional target object to be exposed to ionizing radiation. The at least one target object may include a scintillating gel material. The scintillating gel material may emit light when exposed to the ionizing radiation. An imaging system may be configured to capture at least a first image of the target object from a first position, and a second image of the target object from a second position relative to the target object. A controller may be connected to the imaging system and may be configured to the process the first and second images to provide a three-dimensional dose distribution in real-time.

Abstract: An apparatus for detecting the location of at least one annulus spacer between concentric interior and exterior tubes when a temperature gradient is present therebetween. A probe head assembly is movable within the interior tube. At least one temperature sensor is coupled to the probe head assembly and configured to detect a temperature of an interior surface of the interior tube. A drive assembly is operable to move the probe head assembly relative to the interior tube. A data acquisition system is coupled to the at least one temperature sensor and configured to receive a plurality of temperature measurements in order to identify at least one position along the interior surface having a temperature abnormality corresponding to a reduced temperature gradient.

Abstract: The present invention provides an apparatus for detecting and/or repositioning annulus spacers used to maintain the position of a pressure tube withm a calandria tube of a nuclear reactor. The method comprises the steps of: vibrationally isolating a section of the pressure tube; vibrating the wall of said pressure tube within said isolated section; detecting vibration of the wall at a minimum of two axial positions within said isolated sections; and detecting the reduction in vibration level of the wall at one or more of said axial positions in comparison to the remaining axial positions. The apparatus comprises a tool head to be inserted into the pressure tube, the tool head comprising a first end and a second and a clamping block m each of said ends. The clamping blocks are used to vibrationally isolate a section of the pressure tube located between said ends.

Abstract: The present invention provides a replication device for delivering a replicating material to a surface. The device includes an extrusion piston slidably received therein and movable to a dispensing position for expelling the replicating material though an outlet. The device further includes an actuator, wherein the actuator produces stress waves so as to temporarily reduce the viscosity of the material during delivery of said material. Also provided is a method and kit for using the device for obtaining a replica of a surface.

Abstract: A method is proposed herein to detect high atomic number materials, such as Special Nuclear Materials, within a container based on muon tomography. The container is modeled as a plurality of volume elements. Information related to an initial trajectory and a final trajectory of each muon passing through the container is received. Additionally, a set of initial outer prong vectors and a set of final outer prong vectors are created. Then, a plurality of vector combinations are created from a selected initial vector and a selected final vector. A metric is determined and associated with each vector combination. A subset of the plurality of vector combinations is associated with each volume element and an estimated scattering density is determined and assigned to the volume element. Based on the estimated scattering density assigned to the volume elements, a three dimensional image of the container may be generated.

Abstract: An electrochemical cell for producing hydrogen gas and cupric chloride. The cell comprises: an anode compartment comprising an anode for disposition in an anolyte, wherein the anolyte is cuprous chloride in hydrochloric acid; a cathode compartment comprising a cathode, wherein the cathode comprises an electrocatalyst; a plurality of ion exchange membranes disposed between the anode compartment and the cathode compartment; and at least one center compartment defined by a pair of said ion exchange membranes and comprising at least one element for removal or sequestering of copper ions that cross at least one of said membranes from the anode compartment. Also described is a method for CuCl/HCl electrolysis in the production of hydrogen using the electrochemical cell.

Abstract: A method is proposed herein to detect high atomic number materials, such as Special Nuclear Materials, within a container based on muon tomography. The container is modeled as a plurality of volume elements. Information related to an initial trajectory and a final trajectory of each muon passing through the container is received. Additionally, a set of initial outer prong vectors and a set of final outer prong vectors are created. Then, a plurality of vector combinations are created from a selected initial vector and a selected final vector. A metric is determined and associated with each vector combination. A subset of the plurality of vector combinations is associated with each volume element and an estimated scattering density is determined and assigned to the volume element. Based on the estimated scattering density assigned to the volume elements, a three dimensional image of the container may be generated.

Abstract: The present invention provides a polymer indentation method and tester that includes measuring the time taken by a polymeric material to recover a set portion of an initial deformation and use this duration as a material degradation indicator. The recovery time was found to be more sensitive to cable degradation than the specific compressive stiffness (or indenter modulus) measured during the indentation phase, and this high sensitivity was achieved for both thermally aged and irradiated polymer samples.

Abstract: A portable detection apparatus can include a housing, a first detector for detecting ionizing radiation from a first subject and a second detector within the housing for the detecting the background radiation. A shield within the housing can surround the first and second detectors and define a shield aperture around the first and second detectors for radiation from the subject to enter the housing. A radiation blocking member can substantially block at least a portion of the ionizing radiation from reaching the second detector, whereby radiation detected by the second detector comprises substantially only the background radiation. A processor module can be connected to the first and second detectors for determining the amount of ionizing radiation detected by the first detector attributable to secondary radiation.

Abstract: A circumferential sampling tool for obtaining a sample from an interior wall of a tube has a cylindrical body with an aperture therein. First and second cutters are operatively connected to a shaft for rotation therewith. The first and second cutter are each movable radially between a retracted position and an extended position. First and second actuators are operatively connected to the first and second cutters respectively for moving the first and second cutters between their respective retracted and extended positions as the shaft rotates. Rotating the shaft causes the first cutter to move to the extended position thereby cutting a portion of the interior wall and then causes the second cutter to move to the extended position thereby cutting the sample from the interior wall from a location in the tube revealed by cutting the portion of the interior wall.

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: Processes and devices useful in the application of coatings (14) to the interior of tubes (10) are described. Such processes (40, 400) may include applying a layer (20) of coating fluid (18) to the internal surface (16) of the tube (10) and passing a smoothing member (22) through the tube (10) at a distance from the internal surface (16). The viscosity of the coating fluid (18) may be selected so that the layer (20) of coating fluid (18) has a thickness substantially equal to or in excess of a predetermined wet film thickness (Twf) correlated to a desired final thickness (Tf) of the coating (14). The distance between the smoothing member (22) and the internal surface (16) may substantially correspond to the predetermined wet film thickness (Twf). The smoothing member (22) may smooth the coating fluid (18) and remove coating fluid (18) in excess of the wet film thickness (Twf) from the internal surface (16).