Abstract: Using a solution mining procedure, an ore (10) is treated with a solution of acetic acid and hydrogen peroxide so as to form a leachate containing lead ions. Lead ions (and other metal ions such as zinc and manganese) are stripped (22, 24, 26) by solvent extraction from the leachate to form separate aqueous solutions. The aqueous solution containing lead ions is treated electrochemically in the anodic compartment of a separated electrochemical cell (42) to form a precipitate of lead oxide. Manganese dioxide can be produced similarly (72). A precipitate of zinc hydroxide can be formed in the cathode compartment of a separated electrochemical cell (56). In the cells (42, 72) extracting lead ions and manganese ions, the cathode compartment is used to generate hydrogen peroxide (for use in making the leachant), either directly or indirectly.

Abstract: Cell lysis may be brought about by contacting a suspension of cells with a lysis reagent such as sodium hydroxide solution; subsequent treatment enables organic molecules such as plasmid DNA to be separated from other cell components. Intimate mixing of the cell suspension with lysis reagent is achieved by passage through a fluidic vortex mixer arranged so the residence time of the cell suspension in the mixer is less than the time for lysis to be completed, and may be less than 0.1 seconds. Such a vortex mixer comprises a cylindrical chamber with an axial outlet duct and at least one tangential inlet duct, but with no internal baffles. The low shear stress to which the cell suspension is subjected minimizes loss of product through denaturation or fragmentation of the product, and indeed of contaminants. The subsequent treatment may also utilize a fluidic vortex mixer.

Abstract: A reactor for the plasma-assisted processing of gaseous media comprising a reactor chamber including a gas permeable bed of active material, a power source for applying across the bed of active material a potential sufficient to establish a plasma in a gaseous medium flowing through the bed of active material and a chamber having an inlet stub and an outlet stub for constraining the gaseous medium to flow through the bed of active material, wherein the bed of active material comprises a matrix of beads of a dielectric material having an assembly of regular arrays of beads in each of which adjacent beads are connected to a high voltage input terminal or an electrical ground.

Abstract: A reactor for the plasma processing of gaseous media, especially internal combustion engine exhaust, has a bed made of a body of ceramic material a series of gas permeable electrodes embedded within the bed. The electrodes are distributed to provide a predetermined electric field distribution within the bed.

Abstract: Solvent containing a product (or precursor for the product) and anti-solvent are introduced via tangential inputs respectively 17,18 of a fluidic vortex mixer 11. The emerging mix from axial outlet 20 is supplied directly to a precipitate entrapment device such as filter bed 12 so that precipitate is removed from the solution before the precipitated particles have time to grow. Filtrate is treated in a reduced pressure evaporator 13 to recover anti-solvent and return concentrated solution for combining with a product make up stream at 19 and return to tangential input 17 of the fluidic vortex mixer.

Abstract: The variation in properties of a ferromagnetic material with depth below the surface is assessed in a nondestructive fashion using a probe that incorporates an electromagnet. An alternating magnetic field is generated in the electromagnet and so in the object, and a magnetic sensor is arranged to sense a magnetic field due to the electromagnet. Signals from the magnetic sensor are analysed into an in-phase component and a quadrature component, and these are mapped directly into material property and lift-off components; this analysis enables accurate measurements of material property (such as stress) to be distinguished from changes in lift-off. The measurements are repeated for at least five different frequencies of the alternating magnetic field; and the measurements at different frequencies are deconvolved assuming a functional form for the variation of material property with depth, the function having no more than five unknown constants. The stress at depths for example in the range 0.5 mm to 5.

Abstract: A reactor particularly for the plasma treatment of internal combustion engine exhaust gases, in which a power supply and reactor bed are connected directly and enclosed in an earthed metal chamber which both isolates the high voltage power supply and acts as a Faraday cage preventing the emission of electromagnetic radiation from the power supply or plasma.

Abstract: The thickness of an organic material on a substrate, such as an oil film on a metal sheet (12), is monitored by illuminating the film with ultraviolet radiation (14) and measuring the fluorescent light intensity (44, 48) from the organic material. The reflectivity of the substrate is also monitored, and used in calculating the thickness. The technique is also applicable where the substrate is moving.

Abstract: A spray generator is provided that generates a spray of droplets by the interaction of opposed jets of fluid. The generator comprises a rigid central member defining a central axis, and fluid passageways formed in a block of material leading to two or more pairs of opposed fluid outlets. The outlets of each pair are separated from each other and arranged to generate opposed jets of fluid along an axis parallel to the central axis. Further, the pairs are equi-angularly spaced about the central axis. The outlets of each pair are maintained in axial alignment with each other and at a predetermined axial spacing from each other by a rigid connection between the central member and the block of material. The two or more pairs of outlets together generate a spray of droplets extending 360 degrees about the central axis.

Abstract: An oxide LiMnO2 which has a layered monoclinic structure, and in which a minor part of the manganese may be replaced by another transition metal, is made by a two-stage process. Firstly NaXo2 with a layered structure of the &agr;-NaFeO2-type is made by reacting stoichiometric amounts of a sodium salt and a salt of the metal X in solution so as to form a precipitate, drying and heat treating the precipitate at a temperature between 650 and 720° C. in air, and then rapidly cooling the precipitate to room temperature in air. Then the NaXO2 is subjected to ion exchange with a lithium salt in solution in a non-alcoholic solvent at a temperature between about 140 and 210° C. The resulting lithium manganese oxide can be used as the cathode material in a rechargeable lithium cell.

Abstract: A sensor module for monitoring chemical properties of oil well fluids comprises at least one electrochemical sensor for a chemcal species, for example to detect pH and chloride ion concentration. A micro-porous barrier separates the electrochemical sensors from the environment of the module, the micro-porous barrier being of a material which is readily wetted by water. Periodic application of a current pulse between the barrier and a counter electrode enables fouling material to be removed from the micron barrier.

Abstract: Lithium ion cells in which the cathode contains a particulate insertion material and a binder are cut open in a dry, inert atmosphere (10). The cell components are treated with a first organic solvent (12) to dissolve the electrolyte, so that this can be reused. They are then treated with a second organic solvent (16) to dissolve the binder, and the particulate material separated (18) from the solution of binder. The insertion material is then reduced (22) so that it does not contain intercalated lithium. The reduction process may be performed electrolytically.

Abstract: A method of making a cell component containing a polymer, the polymer consisting primarily of vinylidene fluoride, in which the polymer is mixed with at least one other ingredient, such as an organic plasticiser, and extruded at a temperature above its melting point. The method can be used to make electrolyte layers in which case the polymer would be mixed with at least a salt, and to make layers of composite material for use as anodes or cathodes, in which case the polymer would be mixed with at least a particulate insertion material. No solvents are required.

Abstract: An electrolyte for use in a rechargeable cell whose charging voltage exceeds 3.8 volts includes a redox chemical comprising a substituted aromatic molecule in which &agr; hydrogens are either absent, or are sterically against loss from the ionized form of the molecule. Such as chemical can act as a redox shuttle during overcharge, suppressing damage to the cell and preventing the deposition of metallic lithium during the overcharge of a lithium ion cell, but does not affect normal operation of the cell during either charge or discharge. One such molecule is hexaethyl benzene.

Abstract: A reactor for the processing of gaseous media, including two planar beds of active material separated by a gap. A gaseous medium to be processed is fed inwardly around the periphery of the reactor beds into the gap between the reactor beds and collected from their outer surfaces.

Abstract: A corona discharge reactor is for use in processing materials in or carried by a gaseous phase. A plurality of cylindrical individual reactor chambers is provided in an array. The reactor chambers are electrically matched with each other and pulses of electrical energy are supplied under sequential control to each of the individual reactor chambers.

Abstract: Particles are made from a liquid feedstock (13) containing a pharmaceutical composition, the particles either being solid or being liquid droplets in an aerosol, by supplying the feedstock to an electronic droplet generator (18), and collecting the droplets in a holding chamber (20). Evaporation of the solvent creates particles which may be trapped using a cyclone (22). The generator (18) comprises a feed chamber (28) to which the feedstock is supplied, a dispensing chamber (30) having an inlet port communicating with the feed chamber and having an outlet port (34), and electronic means (36) for repeatedly applying a pressure pulse to the feed chamber and a pressure pulse to the dispensing chamber so that a droplet is ejected. Each droplet is of volume substantially equal to that of the dispensing chamber, so the particles can be substantially monodisperse, and may be of diameter in the range 0.1-20 &mgr;m.

Abstract: A reactor for the plasma processing of gaseous media, especially internal combustion engine exhaust, has a bed made of a body of ceramic material and electrodes. At least one electrode terminates within the bed at a distance from earthed supporting structure to avoid or reduce the risk of tracking or arcing between the electrode and the supporting structure.