Abstract: An arrangement for forming an optical image of the interior of an enclosure contained within a radiation shield the enclosure being one in which remote handling operations are carried out on radioactive material and the shield having a passage therethrough from an outer end to an inner end at the said enclosure, which arrangement includes at or adjacent to the inner end of the passage optical guiding means for guiding optical radiation from scenes within the enclosure along a path through the said passage, located at or adjacent to the outer end of the passage deflection means for deflecting optical radiation which has been guided along the said path and a photodetector arranged outside the shielded enclosure and outside the radiation shield to receive optical radiation which has been deflected by the deflection means.

Abstract: An optical apparatus including a laser producing in use an output laser beam and an optical guide for guiding radiation of the output laser beam when incident thereon and characterised by means for depleting of free charge carriers a region in a path to be traversed by the output laser beam between the laser and the guide.

Abstract: A process for the production of a uranium oxide in which UF.sub.6 is converted by reaction with steam into UO.sub.2 F.sub.2 in a first step and by further reaction of UO.sub.2 F.sub.2 with steam and/or hydrogen in a second step to produce an oxide of uranium, the process being carried out in an apparatus comprising a single kiln vessel having a first region, having UF.sub.

Abstract: A method of purifying a UF.sub.6 gas stream which comprises irradiating the UF.sub.6 gas stream with laser radiation in a vessel in order to selectively convert fluoride impurities in the gas stream to involatile products, removing the purified UF.sub.6 gas stream from the vessel and separately removing the impurities from the vessel.

Abstract: A nuclear fuel element for use in a gas cooled nuclear reactor, such as a Magnox reactor, has a plurality of fuel pin supports defining an element axis passing through the supports. Suspended between the supports are a plurality of fuel pins formed by a stack of oxide fuel pellets within a metal tube. Connected between the supports are a number of elongate members, for example tubular rods, which extend parallel to the axis and are disposed around the fuel pins. One or more of the tubular rods incorporates a doping material, such as gadolinia.

Abstract: A rotor (10) comprising a cylindrical structure (30, 31) including a portion made from a fibre reinforced composite (38, 39) wherein magnetic filler within the matrix (44) of the composite and wherein the loading of the magnetic filler material varies through the matrix whereby the average mass per unit volume of the structure (10) decreases with distance radially from the axis of the structure (10). As a result, strain matching across the rotor can be achieved even when the rotor is spinning at high speed, such as when used in a flywheel energy storage and conversion apparatus.

Abstract: A method for the determination of the surface properties of an object which comprises irradiating the surface of interest with an incident beam of radiation from an optical source, detecting by a detector radiation from the beam scattered by the surface, the detector being located at a predetermined position relative to the surface and the optical source and digitizing and analyzing the image detected by the detector, wherein the incident beam has in cross-section a two dimensional envelope and within the envelope an intensity structure which has multiple edges running in more than one direction which provide information about components of the structure of the beam and the analysis of the image is a two dimensional analysis of the intensity shape and structure of the scattered radiation to provide information about the manner in which the incident beam intensity shape and structure has been changed by scattering at the surface of the object.

Abstract: An automatically-regulated, self-flushing method of filtering a liquid suspension includes passing the suspension through a granular filter material. The flow of suspension is halted to relieve the pressure in the system, so facilitating the settling of the removed particles down the filter. Further settling of the particles may be achieved by passing an airstream through the filter material. A reverse flow of the filtrate then effects a backwashing action on the filter material so that further settling of the particles is encouraged. The filter material may be contained in a drain passage which follows a generally sinuous path. The drain passage may serve a waste landfill site in which toxic, hazardous or domestic waste is disposed.

Abstract: A method and materials are described for the monitoring of ionizing radiation in a location or on a person. The method comprises providing a fluorescent organic sensor material in the location where monitoring is required, the fluorescent organic sensor material having a molecular structure comprising at least one pair of fluorophore units, the units being held together by a spacer unit such that they are capable of interacting to produce a distinct fluorescence spectrum different from those of the individual fluorophore units; exposing the sensor material to the radiation; and determining any change in the fluorescence spectrum of the sensor material after exposure.

Abstract: A storage phosphor material comprising a storage phosphor of the kind in which electrons excited by incident ionizing radiation may be trapped in stable trap sites and subsequently released by stimulation such as photostimulation, wherein the phosphor is contained within a host matrix which comprises a sol-gel glass in which the storage phosphor is incorporated as a dopant.

Abstract: Apparatus for the inspection of the end surface of a cylindrical object including a device for irradiating the end surface of the object, a detector for detecting radiation reflected by the end surface substantially parallel to the axis of the object and a calculator for calculating the proportion of the end surface which has reflected radiation directly to the detector device, wherein the means for irradiating comprises a ring source the center of the ring being substantially co-incident with the axis of the object and being substantially transparent to reflected radiation so that light reflected to the detector passes unhindered through the ring, the ring source having associated therewith a device permitting substantially uniform irradiation across the said end surface.

Abstract: A method of friction welding which comprises forcing together two components to be welded together and providing a relative oscillatory movement between the two components to cause rubbing together of the two components to provide friction welding thereof, said oscillatory movement being caused by means, acting on at least one of the said components, which comprises a magnetostrictive transducer.

Abstract: An on-demand fluorine cell is described together with the construction of a suitable anode and a means of mounting the anode within the cell. The fluorine cell comprises a cell container having a cathode compartment and an anode compartment, the anode compartment having an anode therein, the cathode compartment and the anode compartment having separation means therebetween so as to separate fluorine gas and hydrogen gas generated during operation of said fluorine cell but said separation means allowing passage of electrolyte between said compartments; said anode extending below a lower end of the separation means and being continuously in contact with the electrolyte, control sensor means in at least one of said compartments to sense the level of electrolyte in said at least one compartment; electric current supply means responsive to signals from said control sensor means so as to either start or stop current supply in accordance with said signals.

Abstract: A decontaminating apparatus for removing a layer of contaminated material, such as radioactively contaminated concrete, includes two material removing devices which are driven, alternately, towards and away from one another. Each material removing device includes two rotatable scabbling drums enclosed in a shroud from which removed material is conveyed to a waste collection skip. The material removing devices are mounted at the free ends of two pivotable arms arranged to be driven in mutually opposite directions by a common drive mechanism. A frame supports the two material removing devices, the frame being connected to an articulated arm which extends from a remotely-operated vehicle. The vehicle is located on a platform which can be raised and lowered to facilitate access by the material removing devices to the entire surface under treatment.

Abstract: Apparatus for pulsed electrical power circuitry includes a pulsed power supply circuit, monitor for monitoring a voltage or current characteristic within the supply circuit and an artificial neural network trained to identify whether the detected characteristic is acceptable or harmful and adapted to produce an output accordingly. The circuit may be arranged to deliver its output to a gas discharge load and the output of the trained network may be adapted to be fed to control a parameter in the circuit or in the load whereby a harmful condition in the circuit may be avoided.

Abstract: A wall or other surface is coated by applying a multiplicity of tiles to adhere to the surface, the edges between adjacent tiles being separtated by grouting materila comprising a vitrifiable particulate material incorporated in a binder, and applying local heat from a source of heat to the grouting material to cause vitrification of the particulate material thereby to weld the tiles together.

Abstract: A crimping and cutting device for use on pipes comprises a frame (1 ) provided at one end with an anvil (4) to locate a pipe (P) during a crimping and cutting operation. The device includes a crimping head (18) and a cutting blade (28) which are movable towards the anvil (4) by, respectively, first and second hydraulic actuators (11, 13). The two actuators are mounted coaxially on the frame (1), with the first actuator (11) being operatively connected to the second actuator (13). In operation, the first actuator (11) is operated to move the second actuator (13) which, in turn, moves the crimping head (18) so as to compress the pipe against the anvil (4). Then the second actuator (13) is operated to move the cutting blade (28) through a passage (35) formed in the crimping head (18) so that the blade cuts through the compressed region of the pipe (P).

Abstract: A method of separating a solute from a supercritical fluid which includes reducing the pressure of the supercritical fluid and is characterized in that the supercritical fluid and solute are mixed with another fluid, eg an inorganic or organic solvent under pressure, to cause a partial reduction in the pressure of the supercritical fluid followed by reduction of the pressure of the fluid mixture comprising the supercritical fluid and said other fluid. The fluid mixture pressure reduction may occur in a collection device. Such a device may have a collection solvent already present therein. The said other fluid used partially to depressurise the supercritical fluid may act as a collection solvent in a collection device. The collection device may include one or more collection vessels or alternatively a solid phase trap or a packed column for the purpose of trapping and collecting the solute.

Abstract: A process for the treatment of solid waste material which is or is suspected to be contaminated with plutonium or compounds thereof with or without other hazardous contaminants, which process includes: contacting the said material with and thereby dissolving contaminants as complexes by a liquid medium which comprises Solution X which comprises an aqueous solution which is free of ingredients which are naturally degradable to non-toxic products with or without mild physical assistance such as heat or ultra-violet radiation, said solution comprising:(a) carbonated water;(b) a conditioning agent; and(c) a complexing agent which comprises the anion of a single or multiple carboxylic acid species having from 2 to 6 carbon atoms in each carboxylic acid species;and separating the liquid medium from the waste material and recovering the dissolved contaminants from the liquid medium and wherein the step of contacting the waste material with the said liquid medium is preceded by a step of contacting the waste material

Abstract: A weighing system for obtaining the mass of objects, particularly spent nuclear fuel rods, includes a weighing device having a weighing platform on which objects to be weighed are placed. The platform rests on three hydraulic load cells, each communicating with an associated pressure transducer. Electrical signals from the transducers representing the pressure in the load cells and, consequently, the mass of the objects, are converted into digital form by a convertor and then processed by a computer to calculate the required mass values. The weighing device is located within a radioactive environment existing in a shielded enclosure, the transducer and the signal processing means being situated outside the enclosure and remote from the radioactive environment.