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: An apparatus for holding radioactive objects includes a base and a central pillar extending upwardly between a bottom end coupled to the base and a top end above the base. A plurality of inner segments are spaced around the central pillar, and a plurality of outer segments are spaced around the inner segments to form pairs. The inner segments, the outer segments and the central pillar may be coupled together to permit limited radial movement of at least one of the segments of each pair. Each pair may define a generally vertical, object-receiving channel arranged between the inner and outer segment of the pair. The segments of each pair may be adapted to bear against an object in the channel of the pair to laterally restrain the object and facilitate heat transfer from the object.

Abstract: A method of collecting 3He from a nuclear reactor may include the steps of a) providing heavy water at least part of which is exposed to a neutron flux of the reactor, b) providing a cover gas in fluid communication with the heavy water, c) operating the nuclear reactor whereby thermal neutron activation of deuterium in the heavy water produces tritium (3H) and at least some of the tritium produces 3He gas by ?? decay and at least a portion of the 3He gas escapes from the heavy water and mixes with the cover gas, d) extracting an outlet gas stream, the outlet gas stream comprising a mixture of the cover gas and the 3He gas and e) separating the 3He gas from the outlet gas stream.

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 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: 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 nuclear reactor can include a pressure vessel for containing a pressurized moderator at a first pressure. The nuclear reactor can also include a plurality of fuel channels for a coolant fluid at a second pressure. The plurality of fuel channels are fluidly connected at inlet ends thereof to a coolant supply conduit and are adapted to receive nuclear fuel bundles and to be mounted within the pressure vessel and surrounded by the moderator. The outlet ends of the fuel channels are fluidly connected to a coolant outlet conduit to enable the coolant fluid to circulate from the coolant supply conduit through the fuel channels to the coolant outlet conduit. The plurality of fuel channels maintain separation between the coolant fluid circulating within the fuel channels and the moderator.

Abstract: An apparatus for cleaning heat exchanger tubes and in particular an improved collection system for nuclear generator cleaning and blasting media and deposit material. A suction line having a downwardly directed suction inlet is effective to vacuum airborne media and debris in said chamber and vacuum media and debris deposited on the bottom of said chamber below said suction inlet. A hopper, air jet and shaker means are provided to transport deposited media and debris toward the suction inlet. Breaker and partition means are provided to reduce back-streaming of debris into heat exchanger tubes.

Abstract: Wet proofed catalyst being a hydrophobic porous matrix with catalylically active platinum plus at least one of chromium are titanium dispersed in the matrix.

Abstract: A spacer for maintaining a pressure tube in spaced relation with a caland tube of a nuclear reactor. The spacer comprising a split ring adapted to be disposed about the outer surface of said pressure tube. The ring has a central annular body portion with a raised bearing surface thereon adapted to contact the inner surface of said calandria tube and prevent contact between said outer surface and said inner surface. An annular land projecting from each side of said central body portion is adapted to receive a collar thereon effective create an interference fit between said ring and said pressure tube and thereby constrain axial movement of said spacer on said pressure tube. The spacer of the present invention maintains its location on the pressure tube and does not suffer the axial movement which characterizes some conventional spacers. The bearing surface can have a coating to reduce wear and heat transfer.

Abstract: Absorbed dose in a product being irradiated by an electron beam is determined by measuring the collectable current in a beam stop and correlating the current to absorbed dose.

Abstract: An electrolytic pre-enrichment of a feed stream to a combined electrolysis nd catalytic exchange ("CECE") heavy water production process. A deuterium enriched liquid or vapour stream from electrolytic cells is applied as a feed to the first stage of a CECE deuterium enrichment process. By deploying a portion of available electrolytic cell capacity in the pre-enrichment stage, advantages are achieved, particularly where available electrical power fluctuates or when a "turned down" CECE process is desired.

Abstract: A method for selectively photoionizing odd mass Zr atoms. Atomic vapours are subjected to two resonant laser pulses to raise the energy of Zr atoms from the J=2 ground state, to a J=1 first intermediate state and to a second intermediate state prior to ionization. Quantum mechanical selection rules applicable to linearly polarized light and hyperfine interactions are exploited to produce odd mass selectivity.

Abstract: A method for selectively photoionizing odd mass Zr atoms. Atomic vapours are subjected to three resonant and are non resonant laser pulses to raise the energy of Zr atoms from the J=2 ground state, to a J=1 first intermediate state, to a J=(second intermediate state and to a third intermediate state prior to ionization.

Abstract: A method of determining the rate of air leakage from or into a containment is described. The internal pressure of the containment is maintained at a positive or negative value with reference to ambient air pressure and the air mass changes are continuously monitored through measurements of pressure, temperature, relative humidity and free volume. Air leakage is measured through a mass balance equation and a regression analysis carried out to yield constants which characterize the various features of the leakage flow and give an indication of the accuracy of the results.

Abstract: A method of generating a computed tomographic image of a region-of-interest of a sample is described in which only the region-of-interest need be scanned, i.e. it is not necessary to scan the entire sample. Reference data for the region-of-interest of a complete reference object that is a relatively good match to the sample outside the region-of-interest and has a known attentuation distribution inside the region-of-interest is first obtained. This can be done by scanning only the region-of-interest of an actual complete reference object or by constructing a digital image of the reference object and mathematically scanning only the region-of-interest of the image. Then the region-of-interest of the sample is scanned to obtain sample data from which the reference data is subtracted. A differential image is reconstructed from the differential data thus obtained. The method allows the use of equipment which is simpler, more compact and less costly than conventional CT equipment.