Abstract: A method determining the plutonium content of a material containing fluorine involves obtaining the mass ratio of plutonium in a compound comprising plutonium and fluorine, particularly plutonium tetrafluoride, to the total plutonium content. The method utilises a high resolution gamma ray spectrometry technique to obtain a count rate in a pair of gamma ray photopeaks. One of the photopeaks has an energy level of 414 keV, resulting from the decay of plutonium-239, and the other photopeak has an energy level of 583 keV, resulting from the decay of an excited sodium-22 nucleus following an (alpha,n) interaction with fluorine.

Abstract: A submersible pump for pumping radioactive liquids comprises a pump cartridge (2) which is removably mounted in a cavity (3) formed in the pump body (1). Seals (30a, 30b) are provided between the cartridge (2) and the cavity (3). The cartridge houses a pneumatically operated motor to drive an impeller which discharges liquid through an outlet duct (10). Compressed air required for driving the motor is supplied through an air inlet tube (12) and air exhausted from the motor is conveyed through an air outlet tube (14). Both the air inlet and the air outlet tubes extend through the interior of the outlet duct (10).

Abstract: An apparatus for sampling a solidified body in a vessel. The apparatus includes a tubular outer member and a tubular inner member slidable one within the other in close telescopic relationship. A datum location is provided for locating the inner member in an axial and radial datum location in the outer member. In the datum location the outer and inner members define a plurality of longitudinally displaced transverse holes therethrough to permit flow of the body whilst in a fluid state from the outside of the outer member to the inside of the inner member. A sample of the body is provided in the inner member. The solidified body may comprise vitrified highly radioactive waste or intermediate level radioactive waste incorporated in a setting material such as cementitious grout.

Abstract: In an airlock system, through which drums containing radioactive material are transferred into a containment area, a passage has an intermediate region, of reduced cross section relative to the inlet and outlet ends of the passage. The passage has a convergent inlet region and a divergent outlet region leading, respectively, to and from the intermediate region. The passage functions in the manner of a venturi so that an airstream is caused to flow along the passage towards the containment so as to inhibit the escape of atmosphere therefrom. A roller conveyor transfers the items through the airlock system and a detector monitors the atmosphere in the passage.

Abstract: A rotary kiln, particularly for producing uranium dioxide from uranium hexafluoride, has an inlet arrangement and a heated rotatable barrel. Uranium hexafluoride and steam react together in the inlet arrangement to form uranyl fluoride which is fed into the barrel by the aid of a rotating scroll feed device. In the barrel, the uranyl fluoride reacts with a counterflow stream of steam and hydrogen to produce the uranium dioxide. A porous metal or ceramic filter closely surrounds the scroll feed device to remove particles from kiln-produced gases. The filter is maintained in a clean condition by the scraping action of a number of helical blades forming part of the scroll feed device. The uranium dioxide powder produced by the kiln may be processed to form nuclear fuel pellets.

Abstract: Apparatus for automatically measuring the density an object which comprises a first weighing device for weighing the object in a first medium which is dry, a second weighing device for weighing an object in a second medium which is wet and a robotic device having a first gripper to grip the object when dry and a second gripper to grip the object when wet the device being capable of controlling the first gripper so as to place the object on and remove it from the first weighing device and for controlling the second gripper so as to place the object on and remove it from the second weighing device.

Abstract: An apparatus for monitoring the inductance of a coil (L1) which is not part of a resonant circuit including a second coil (L2) connected in series with the first mentioned coil and a resonant circuit which is formed by connection of a capacitor (C5) to the second coil, or optionally (C2) to a third coil (L3) which is in a mutually inductive relationship with the second coil so that the second and third coils act as the primary and secondary coils of a transformer (M), a device (1) for injecting into the circuit containing the first mentioned and second coils an a.c. signal of substantially constant peak voltage amplitude having a frequency within the resonance peak of the resonant circuit, and an amplitude detector (5) for measuring the amplitude of the voltage across a component of the resonant circuit. The apparatus may be employed as so-called integral control in closed loop control of the suspension of an object by the first mentioned coil.

Abstract: A process for the measurement of the level of radioactivity of a solid by contacting the solid with a chemically stable reactant fluid. The reactant fluid is converted by nuclear radiation to a chemically stable product fluid to an extent dependent upon the radioactive content of the solid. The amount of the reactant fluid converted into the product fluid is detected in order to determine the level of radioactivity of the solid.

Abstract: Removal of a target metal having an insoluble phosphate (e.g. actinides), is effected by passing the solution through a bioreactor containing an immobilised phosphatase-producing microorganism which has been cultivated using a culture medium containing an assimilable organic source of phosphorus and which has been primed with an element, other than the metal to be removed, having an insoluble phosphate so as to deposit the phosphate of the priming element on cell surfaces of the microorganism. The priming element phosphate facilitates deposition of the target metal phosphate.

Abstract: A method and apparatus for transferring relatively light objects. The objects are supported on a cushion element having a multiplicity of extremely fine and relatively short flexible fibers packed at an ultra high density pile in a backing. The fibers are aligned at an angle or inclination with respect to the base so that when the cushion element or the object is vibrated the objects are transferred in the direction of lay of the fibers.The cushion element may be supported by a base with the object resting on the fibers, or the cushion element may be secured to the underside of the object so that the fibers rest on the base.

Abstract: In a method of detecting the spatial position of a laser beam relative to a body locatable in the path of the laser beam by detecting an acoustic signal produced by the beam in the body, wherein the laser beam carries a power modulation signal and the body has a plurality of acoustic sensors for detecting the acoustic signal produced in the body by the laser beam, the method includes detecting in the outputs of the acoustic sensors signals corresponding to the power modulation of the incident laser beam and detecting any difference in phase between the detected signals. A processor may be provided for processing the outputs of the acoustic sensors, the processor including a sensor for sensing in the respective outputs signals corresponding to the power modulation of the output beam of the laser and a phase sensitive detector for detecting differences in phase between the detected signals.

Abstract: A dilution technique for measuring the flow rate of a fluid stream includes injecting a tracer gas into a gas stream and then introducing the resulting tracer stock gas stream at a constant flow rate into the fluid stream. The concentration of tracer stock gas in a fluid stream sample is then obtained. A sample of the tracer stock gas stream is obtained at a point before this stream is introduced into the fluid stream. The resulting tracer stock gas stream sample is injected at a flow rate which can be varied, for example, by a peristaltic pump, into the gas stream. The concentration of a sample from the resulting tracer stock gas sample-in-gas stream sample is measured. By varying the flow rate of the tracer stock gas stream sample the two measured concentrations can be equalized. When the concentrations are equal, a relationship exists between the flow rates of the fluid stream, the tracer stock gas stream and the tracer stock gas stream sample.

Abstract: An apparatus for the detection of surface defects on cylindrical objects which includes means for conveying the objects to be inspected one-by-one each on its end to a first inspection station, means for inspecting the free end of each object as it passes through the first inspection station, means for conveying the objects one-by-one each on its side to a second inspection station the means for tipping the objects from their ends to their sides, means for rotating each object whilst passing it on its side through the second inspection station, means for inspecting the curved surface of each object as it passes through the second inspection station, means for conveying the objects one-by-one to a third inspection station the said means including means for tipping the objects onto their end inspected at the first inspection station and means for inspecting the free end of each object as it passes through the third inspection station.

Abstract: An apparatus for measuring properties of a slurry which comprises a slurry transporting section (16), means for measuring (14a) at a first inspection site the particle size distribution of a slurry entering the transporting section, means for measuring (14b) at a second inspection site the particle size distribution of slurry leaving the transporting section and means for calculating (13a, 13b) from the particle size distribution measured at the first and second inspection sites a parameter related to the floc strength of the slurry which has passed between the first and second inspection sites.The transporting section may comprise a pipe which includes a flow constriction.The transporting section may be a removable section fitted between a slurry inlet means and an outlet means.The said means for calculating may calculate one or more regression coefficients which define the curve described by the floc mass size equation or the breakage ratio define by the mean floc sizes before and after breakage.

Abstract: A rotor especially for use in a high speed electric motor/generator comprises fibre-reinforced plastics material incorporating magnetic filler material, the fibre-reinforced plastics material being arranged as a multi-layered cylindrical portion of the rotor, the magnetic filler material being disposed within and between the layers. The said cylindrical portion may be a hollow tubular-portion. The said portion may be enclosed in a non-composite eg, wear resistant, layer.

Abstract: Apparatus for the inspection of the end surface of a cylindrical object including means for irradiating the end surface of the object, detector means for detecting radiation reflected by the end surface substantially parallel to the axis of the object and calculator means for calculating the proportion of the end surface which has reflected radiation directly to the detector means, 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 means passes unhindered through the ring, the ring source having associated therewith means permitting substantially uniform irradiation across the said end surface.

Abstract: A method of treating a concrete or other non-metallic surface contaminated with embedded radionuclides to reduce the total level of radioactivity in a concrete or other hydraulically bonded material body is described. The method comprises the steps of producing relative mutual movement between the surface to be removed and a laser heat source such that a layer adjacent the surface is caused to be detached from said concrete body. The surface may be detached as a vapour, in flakes or as a sheet.

Abstract: The length of an object, particularly a spent fuel rod, is measured by taking an optical image of a support surface and then taking an optical image of a fuel rod when placed on the support surface. The two optical images are digitised, stored and then processed to obtain a difference in grey level values between the two stored images. The two images are stored as a plurality of columns each containing pixels having a grey level value. Using an algorithm, the difference between these values in corresponding columns of the two images are determined as root mean square values. The columns are processed in turn to determine which have a root mean square value above a threshold value, these being representative of the presence of a fuel rod. The number of such columns is a measure of the fuel rod length.

Abstract: A method of decontaminating the surface of a body carrying radioactive contaminants which comprises treating the surface with a decontaminant comprising a solution of tetrafluoroboric acid HBF.sub.4, treating the resultant liquor comprising decontaminant and dissolved species removed from the body surface with a first chemical agent which on reacting with dissolved species yields insoluble compounds and regenerated decontaminant solution, and characterized in that the regenerated decontaminant solution is further treated to cause removal of the first chemical agent from the decontaminant solution.

Abstract: Metals have phosphates of low water solubility e.g. Cd, Pb, Cu, Mn, Sr, U, La, Pu, Am and Np, are removed from water by reaction with phosphate produced by enzymatically-cleaved polyphosphate which has been accumulated by one or more polyphosphate-accumulating microorganisms.