Abstract: A process for the electrochemical dissolution of a metallic structure having a plurality of electrically conducting components comprises utilising the structure as a sacrificial electrode in an electrochemical cell so as to dissolve at least part of the strcuture. The process is characterised in that, prior to the use of the structure as a sacrificial electrode, molten metal is allowed to solidify about the structure so as electrically to connect together the components.

Abstract: A method of removing from a metal salt ionic species contained therein involves contacting the metal salt with an ionic liquid to dissolve the metal salt, the ionic species or both. At least in the case where both the metal salt and the ionic species are dissolved, the resultant ionic liquid composition is treated to separate the ionic species therefrom and subsequently processed to recover the metal salt.

Abstract: A method for polymerizing an alkyl-substituted aromatic compound comprises reacting the alkyl-substituted aromatic compound in the presence of a molecular sieve such that the aromatic compound polymerizes.

Abstract: The invention provides a technique for correcting gamma ray intensities detected to account for variation in attenuation effects with energy. The corrected intensity values enable more accurate isotopic analysis to be conducted and render such techniques applicable to low level emission cases. The technique is particularly useful in investigate waste materials with a gamma emitting content which needs to be determined. The attenuation is corrected for using a bi- modal function to account for the attenuation effects arising from low and high atomic mass components of the material in which the emitters are present.

Abstract: The spent nuclear fuel reprocessing method includes contacting an organic phase containing Np(VI) with a hydrophilic substituted hydroxylamine in which at least one N—H hydrogen of the hydroxylamine is replaced by an organic substituent, there being at least one such organic substituent having one or more hydroxyl groups. Np(VI) is reduced to Np(V), which is then backwashed into an aqueous phase.

Abstract: A method for the removal of embedded contamination from a metallic surface in which a laser beam is directed on to the contaminated surface. The laser beam has sufficient power density to cause direct ejection of laser-generated melt pool liquid from the metallic surface thereby removing a metallic surface layer containing the embedded contamination. Means are provided for the collection of laser ejected material in order to prevent recontamination of the metallic surface or contamination of previously uncontaminated surfaces.

Abstract: A system for criticality incident detection is described. The system comprises a plurality of sensors at least partially comprised of storage phosphors. The sensors are distributed throughout the environment to be monitored. The sensors are coupled to a central detection system comprised of at least a luminescence detector and a processor. The luminescence detector measures the luminance of the sensors and provides that measurement to the processor. The processor then calculates the radiation level that the luminance measurement corresponds to. In other embodiments, monitoring units are installed in various portions of the environment being monitored. The monitoring units accept the sensors and are coupled to the central detection system so that the remote monitoring units can be interrogated from the central detection system.

Abstract: The invention is concerned with the minimization of radiological doses during manufacturing processes of fuel assemblies, by employing non-irradiated fuel as a shielding material against the radiological output of re-processed fuel materials. The non-irradiated fuel can be employed in peripheral fuel rods and/or in the end portions of fuel rods with beneficial effects.

Abstract: A collection method for an at least partially ionised sample is provided in which the part of the sample to be collected is discharged using an electrical conductor and the discharge part of the sample then leaves the confines of a retaining magnetic field. The discharged part of the sample and the non-discharged part are separated as a result. The collector and collection method are particularly suitable for use with ion cyclotron resonance where different parts of the sample are provided with a higher energy level to other parts.

Abstract: An electrochemical ion exchange cell comprises a metal carbollide as ion exchange material. The carbollide is preferably a polynuclear cobalt dicarbollide and is typically substituted by chlorine. Also novel are polynuclear metal carbollides comprising a substituted carbollide cage, as well as metal carbollides comprising a carbollide cage substituted by a moiety having a —COOH or —SH group.

Abstract: A composite bioreactor and a method of using same is described. The bioreactor (10) comprises a combination of a sulfur oxidizing bacteria (SOB) bioreactor (12) directly on top of a sulphate reducing bacteria (SRB) bioreactor (14); the SOB bioreactor (12) comprising a heap of said soil to be rernediated and having suitable microorganisms therein to react with degrade contained contaminants; said SRB bioreactor comprising trough means (18) having support means to support said soil heap associated with an opening thereof, said support means having permeable membrane (16) associated therewith to allow passage of liquid but substantially no soil and sulfur reducing bacteria within said trough means (18); and liquid and nutrient supply means to promote growth of said sulfur oxidizing bacteria and said sulphate reducing bacteria within said composite bioreactor.

Abstract: A spent nuclear fuel reprocessing method includes contacting an organic phase containing NP(VI) with an oxime of the formula R2C═NOH, where each R is independently H or an organic substituent. Np(VI) is reduced to Np(V) which is then backwashed into an aqueous phase.

Abstract: A transport container for nuclear fuel is provided with an outer container having internal insulation, the insulation defining an internal cavity. The cavity receives a plurality of fuel containers wherein the internal volume of the fuel containers is at least 5% of the external volume of the outer container. The container allows substantially higher volume proportions of enriched fuel to be safely transported than is possible with prior containers.

Abstract: Ions produced by radioactive gases present in air impact on the sensitivity of contamination measuring instruments which detect ions generated by radioactive materials present on an item. Methods and apparatus address this issue by conducting a measurement of ions generated in a chamber by gaseous emitters and other background events in a volume of medium and deducting this from a measurement of ions generated in another chamber by the item as well as the gaseous emitters and background events. The variation of the gaseous emitters present within the medium is addressed by moving the medium about. An alternative solution uses a medium free of gaseous emitters having a significant level, for instance by sealed storage of air prior to its use in a method and instrument.

Abstract: A process is disclosed for the treatment of a solvent which has been used in nuclear fuel reprocessing or uranium ore purification, the solvent comprising an organophosphate ester and a hydrocarbon diluent. The process includes distilling the solvent under reduced pressure to remove substantially all the diluent and a major proportion of the organic ester, converting organophosphate to inorganic phosphate and encapsulating the residual material.

Abstract: A method of dissolving in an ionic liquid a metal in an initial oxidation state below its maximum oxidation state, characterized in that the ionic liquid reacts with the metal and oxidizes it to a higher oxidation state. The initial metal may be in the form of a compound thereof and may be irradiated nuclear fuel comprising UO2 and/or PuO2 as well as fission products. The ionic liquid typically is nitrate-based, for example a pyridinium or substituted imidazolium nitrate, and contains a Bronstead or Franklin acid to increase the oxidizing power of the nitrate. Suitable acids are HNO3, H2SO4 and [NO+]. Imidazolium nitrates and certain pyridinium nitrates form one aspect of the invention.

Abstract: Apparatus suitable for vitrifying nuclear waste comprises a tunable microwave cavity connected by a first wave guide to a source of microwave energy; cooling coils for cooling the exterior of the cavity; a hopper for loading particulate fusible material to the interior of the cavity; within the cavity a crucible made of melted and re-solidified fusible particulate material; an exit-chamber connected by a second waveguide to a second microwave source; and a pipe for supplying argon gas to the exit chamber so that a plasma torch can be generated. The separating of the crucible form the cavity walls by unmelted material gives significant advantages in case of cleaning and reduced energy consumption.

Abstract: A method for producing a system adapted to interact with a dissolved species, the method comprising providing a first component incorporating a complexing functionality, X, and a polymerizable functionality, R, the complexing functionality being capable of forming a complex with the dissolved species, and providing a second component polymerisable with the first component, the method involving contacting the first component with a species with which it complexes and subsequently contacting the complexed first component with the second component and polymerizing the two to produce a polymer incorporating the complexing functionality X, the method further comprising the removal of the complexed species from the functionality X, wherein the complexable functionality is selective from functionalities of the formula: ═CTCOOH, where T is hydrogen or any halogen (most preferably chlorine), methyl and halogen substituted forms thereof, or ≡CCOOH; or PhCOOH.

Abstract: A centerless grinding machine having a control wheel and a grinding wheel for machining cylindrical workpieces is adjusted prior to a machining operation using a setting component having the same diameter as the workpiece. The setting component is used so as to ensure that a surface of the control wheel is aligned with a guide surface of an outlet guide so as to facilitate accurate machining. Relative movement of the control wheel and the outlet guide enables an electrically conducting portion of the setting component to complete an electrical circuit when the two surfaces are in alignment. A current meter is activated when alignment is achieved. The setting component enables the machine to be adjusted at a remote location. The machine may therefore be located within a shielded enclosure for machining nuclear fuel pellets.

Abstract: The apparatus and method provide techniques for monitoring the position on alpha contamination in or on items or locations. The technique is particularly applicable to pipes, conduits and other locations to which access is difficult. The technique uses indirect monitoring of alpha emissions by detecting ions generated by the alpha emissions. The medium containing the ions is moved in a controlled manner frog in proximity with the item or location to the detecting unit and the signals achieved over time are used to generate alpha source position information.