Abstract: A system and a process for producing selected isotopic daughter products from parent materials characterized by the steps of loading the parent material upon a sorbent having a functional group configured to selectively bind the parent material under designated conditions, generating the selected isotopic daughter products, and eluting said selected isotopic daughter products from the sorbent. In one embodiment, the process also includes the step of passing an eluent formed by the elution step through a second sorbent material that is configured to remove a preselected material from said eluent. In some applications a passage of the material through a third sorbent material after passage through the second sorbent material is also performed.

Abstract: A computer implemented method for modelizing a nuclear reactor core, including the steps of: partitioning the core in cubes to constitute nodes of a grid for computer implemented calculation, calculating neutron flux by using an iterative solving procedure of at least one eigensystem, the components of an iterant of the eigensystem corresponding either to a neutron flux, to a neutron outcurrent or to a neutron incurrent, for a respective cube to be calculated. A control parameter is varied to impact a neutron eigenvalue ? through a perturbed interface current equation and drive the neutron eigenvalue ? towards 1.

Abstract: A boiling water reactor has a reactor pressure vessel and a through piping. The reactor pressure vessel includes a main body trunk and an openable upper lid covering an upper open end of the main body trunk from above. The through piping penetrates lateral side of the main body trunk and has an opening section at a same level with or higher than the upper open end of the main body trunk in the reactor pressure vessel. The through piping may be connected to the sump arranged outside the reactor pressure vessel in the dry well. The through piping may be further connected to the suppression pool in the wet well and/or to the water level gauge in the dry well.

Abstract: In a nuclear power plant, a corrosion-resistant oxide film on a surface of the metal component of a reactor structure is exposed to a high-temperature water, the corrosion-resistant oxide film containing an oxide having a property of a P-type semiconductor, and a catalytic substance having a property of an N-type semiconductor is deposited on the oxide film. The oxide film maintains the property of the P-type semiconductor.

Abstract: In a method of reducing corrosion of a material constituting a nuclear reactor structure, an electrochemical corrosion potential is controlled by injecting a solution or a suspension containing a substance generating an excitation current by an action of at least one of radiation, light, and heat existing in a nuclear reactor, or a metal or a metallic compound forming the substance generating the excitation current under the condition in the nuclear reactor to allow the substance generating the excitation current to adhere to the surface of the nuclear reactor structural material, and by injecting hydrogen in cooling water of the nuclear reactor while controlling the hydrogen concentration in a feed water.

Abstract: A method and apparatus for a Boiling Water Reactor (BWR) jet pump inlet mixer support that provides rigid support for inlet mixers. The inlet mixer support attaches to a conventional BWR jet pump assembly to pull the inlet mixer away from the centerline of a riser pipe or maintain the existing inlet mixer position. The inlet mixer support may provide redundant support that may otherwise be provided by set screws of a conventional restrainer assembly. The inlet mixer support may, alternatively, be used in lieu of conventional set screws. The inlet mixer support may also counter-act additional side loading that may be applied to inlet mixers to stabilize inlet mixer movement and vibration when the BWR jet pump assembly is in operation. Optionally, the inlet mixer support may also prevent removal of existing restrainer bracket set screws.

Abstract: A method and apparatus for physically restraining an inlet mixer of a boiling water reactor (BWR) jet pump assembly. An inlet mixer clamp assembly is attached to the top of a transition piece of the BWR jet pump assembly, to provides a downward clamping force on the top of the inlet mixer. The clamping force restrains the inlet mixer from experiencing vibration and mitigates leakage between the inlet mixer and the transition piece sealing surfaces of the jet pump assembly. The clamping force also restrains the inlet mixer from undesirable rotation, especially during operation of the jet pump assembly. The inlet mixer clamp assembly may be used as an alternative to conventional jet pump beam assemblies. Alternatively, the inlet mixer clamp assembly may be used as a redundant physical restraint in addition to the conventional jet pump beam assemblies.

Abstract: A compression sleeve for use in BWR jet pump sensing line repairs is configured to maintain its physical characteristics in an operating nuclear reactor environment. The sleeve includes shaped ends to accommodate deformation and flow of the sleeve so as to form a seal between jet pump sensing line components. A mechanical coupling assembly for repairing a jet pump sensing line is configured to include the compression sleeve.

Abstract: A method and apparatus for the calibration of neutron flux monitoring devices used in a nuclear reactor core. The apparatus includes a transverse in-core probe (TIP) cable with a neutron absorber located a fixed distance apart from a TIP detector. The neutron absorber may be passed within close proximity of the neutron flux monitoring device such that a perceived drop in measured neutron flux occurs, whereupon the cable may be repositioned relative to the monitoring device to ensure that the TIP detector is within close proximity of the monitoring device for purposes of calibrating the monitoring device.

Abstract: A capsule for holding, irradiating, and eluting a material is provided. Methods of fabricating and using the capsule are also provided. The capsule may include a multidiameter tube with a first end region, a second end region, and a middle region. Washers and filters are provided in the end regions and the end regions may be sealed using various methods and materials with the end caps press fit into the end regions. The middle region is designed to store a material to be irradiated by a neutron flux source. The capsule components may be made from materials having a low nuclear cross section so that the capsule may be handled safely after an irradiation step is performed. The capsule is also designed to have a symmetric configuration as an elution and irradiation column so that the same capsule may be used to elute the material within the middle region of the capsule after an irradiation step is performed.

Abstract: A access apparatus is set on instrumentation nozzles penetrating a bottom portion of a reactor pressure vessel, in the reactor pressure vessel filling water. The access apparatus has an arm turned, and a mounting fixture that can move along the arm and having a holding member. A cover apparatus having a guide pipe covers the access apparatus, and is installed on the bottom portion in underwater environment in the reactor pressure vessel. The water below the cover apparatus is drained from the reactor pressure vessel to form an air space below the cover apparatus. A variety of device heads is suspended and lowered in the air space through the guide pipe, and mounted to the holding member of the mounting fixture. Repair or preventive maintenance operation against the instrumentation nozzles is performed by the variety of device heads.

Abstract: A power module assembly includes a reactor core immersed in a coolant and a reactor vessel housing the coolant and the reactor core. An internal dry containment vessel submerged in liquid substantially surrounds the reactor vessel in a gaseous environment. During an over-pressurization event the reactor vessel is configured to release the coolant into the containment vessel and remove a decay heat of the reactor core through condensation of the coolant on an inner surface of the containment vessel.

Abstract: Disclosed is a basket 50 that is located within a basket containment vessel, into which a boric acid solution capable of dissolving a pH adjuster flows, and can allow a pH adjuster solution to flow out by the inflowing boric acid solution. The basket 50 includes a plurality of containment units 71 stacked in a vertical direction with a predetermined first space L1 therebetween. The pH adjuster can be stored in each of the containment units 71. Also disclosed is a pH adjusting device including the basket 50, the basket containment vessel in which the basket 50 can be contained and in which cooling water can be stored, and an overflow pipe that, within the basket containment vessel, allows the pH adjuster solution that is obtained from the pH adjuster dissolved in the cooling water to flow out.

Abstract: A non-destructive assay of deactivation of the contents of explosives and chemical warfare on-field (and or in lab) is presented with high-energy neutrons at 14, 4 and 2 MeV. The elements and substances present in the munitions are transmuted into passive elements through neutron-alpha nuclear reactions. Deactivating of the explosives on-field is presented with a unique and compact neutron generator fueled with deuterium gas and tritium breeder. Several high explosives and chemical warfare are presented in the transmutation with physical analysis. The present method and technique can be employed on-field as an improvised explosive device and as a precise explosive device in labs and centers.

Abstract: A system for receiving and storing high level radioactive waste comprising: an enclosure comprising walls having inlet ventilation ducts, a roof comprising an array of holes, and a floor; an array of metal shells located in an internal space of the enclosure, the array of metal shells being co-axial with the array of holes in the roof so that containers holding high level radioactive waste can be lowered through the array of holes in the roof and into the array of metal shells; the array of metal shells acting as load bearing columns for the roof; and each of the metal shells comprising (i) an expansion joint for accommodating thermal expansion and/or contraction of the metal shells; and (ii) one or more holes at a bottom portion of the metal shell.

Abstract: A neutron generator and isotope production apparatus and method of using the same to produce commercially and medically useful neutrons. The gamma,n reaction produces neutrons in beryllium and deuterium and the spectrum of the neutrons generated is shaped to optimize capture of the neutrons in a gamma emitting isotope. The gammas interact with target materials to produce large quantities of neutrons.

Abstract: Example embodiments are directed to tiered tie plates and fuel bundles that use tiered tie plates. Example embodiment tie plates may include upper and lower tiered tie plates. Example embodiment tiered tie plates may have a plurality of bosses divided into groups, or tiers, having differing vertical (axial) displacement. Example embodiment fuel bundles may use tiered tie plates such that fuel rods in example bundles may originate and terminate at different vertical displacements, based upon the vertical displacement of the bosses receiving the fuel rods into the tiered tie plates. Optionally, shanks may be used to further vary fuel rod axial displacement and diameter.

Abstract: A device for supporting nuclear fuel plates (4) with a longitudinal axis (X) including a bottom (6) forming a lower longitudinal end of the supporting device and a lid (8) forming an upper longitudinal end of the supporting device, the bottom (6) and the lid (8) being rigidly connected to each other through a central connecting means and peripheral connecting means, a plurality of upper means (18) for supporting the plates (4) attached to the lid (8), and a plurality of lower means (16) for supporting the plates (4) attached to the bottom (6), ensuring elastic support of the longitudinal ends of the plates (4) in a direction of the width (R) of the plate (4) and allowing free deformation of said longitudinal ends in the direction of the thickness (T) of the plate.

Abstract: In a method for improving the energy generating output of a nuclear reactor containing one or more fuel rods in one or more fuel rod bundles while satisfying a maximum subcritical banked withdrawal position (MSBWP) reactivity limit, enrichments of individual fuel rods in an axial cross-section of a lattice being evaluated at the top of the fuel bundle are ranked, and the fuel pins of the highest ranked rod location in the lattice are replaced with pins containing natural uranium. A core simulation is then performed to determine whether there is any margin to a MSBWP reactivity limit. For each lower ranked candidate rod position, the pin replacing and core simulation functions are repeated until no rod location violates the MSBWP reactivity limit, so as to achieve a desired lattice design for the top of the fuel bundle.

Abstract: Methods for detecting and identifying carbon- and/or nitrogen-containing materials are disclosed. The methods may comprise detection of photo-nuclear reaction products of nitrogen and carbon to detect and identify the carbon- and/or nitrogen-containing materials.