Abstract: A valve system (10) controls the fluid flow between an inlet (12) and an outlet (14). The system (10) splits the flow into two parallel flow ducts (15, 16) and recombines the flows through opposed tangential inlets (18) and (19) of a fluidic vortex valve (20) which has an axial outlet (22). An adjustable valve (24) controls the flow through one of the parallel flow ducts (15), controlling the strength of the vortex generated within the vortex valve (20). Hence a small valve (24) can control and adjust the flows in both ducts (15 and 16).

Abstract: A catalytic material for the plasma-assisted treatment of the exhaust gases from internal combustion engines, consisting of an activated alumina, which contains silver or molybdena (MoO3). For silver doped alumina, a preferred silver concentration is between 0.1% and 5% by weight. The preparation and use of silver doped alumina material also is described.

Abstract: In a non-thermal plasma reactor (300), at least a component of the active material (320) is selected or modified to provide the capability to adsorb or trap a predetermined chemical species in the gas flow thereby to increase the effective residence time of said species relative to the residence time of unadsorbed species in the gas flow.

Abstract: Small crystals are made by mixing a solution of a desired substance with an anti-solvent in a fluidic vortex mixer in which the residence time is less than 1 s, for example 10 ms. The liquid within the fluidic vortex mixer (12) is subjected to high intensity ultrasound from a transducer (20, 22) in or on the wall of the mixer, or coupled to a pipe supplying liquid to the mixer. The solution very rapidly becomes supersaturated, and the ultrasound can induce a very large number of nuclei for crystal growth. Small crystals, for example less than 5 ?m, are formed that may be of a suitable size for use in inhalers.

Abstract: A method and apparatus for removing nitrogen oxides from internal combustion engine exhaust emissions consisting of the operations of contacting the exhaust emissions with a non-thermal plasma (1) and a silver doped alumina catalyst (2) and then an indium-doped zeolite catalyst (3).

Abstract: A reactor for the plasma-assisted processing of a gaseous medium, including a pair of electrodes having facing surfaces the separation of which is substantially uniform, with a body of dielectric material positioned between them and defining a plurality of gas passages extending through the space between the electrodes.

Abstract: A reaction chamber (12, 49) is adapted to be coupled to a source of microwave radiation. A pair of opposed field enhancing electrodes (18, 21; 62, 63) concentrate microwave energy so as to form plasma in a localised region between the electrodes. Gas passages are arranged for passing a gaseous medium into and out of the chamber so that the gaseous medium passes through the said localised region of plasma. The electrodes comprise electrically conducting tubes (18, 21; 62, 63) held in electrode holders (17, 19; 53, 54) located in the chamber wall, the electrode tubes being removable and replaceable from outside of the apparatus.

Abstract: A chemical plant for performing a chemical reaction between particles of a material such as lithium metal, and a reagent such as butyl chloride in solution in hexane, in which one reaction product is a solid material, includes a reaction vessel (12). Several ultrasonic transducers (16) are attached to a wall of the vessel (12) so as to irradiate ultrasonic waves into the vessel, the vessel being large enough that each transducer irradiates into fluid at least 0.1 m thick, each transducer irradiating no more than 3 W/cm2, and the transducers being sufficiently close to each other and the number of transducers being sufficiently high that the power dissipation within the vessel is at least 10 W/liter but no more than 200 W/liter. The high intensity of ultrasound ensures that lithium chloride is cleaned off the surface of lithium metal particles throughout the vessel (12).

Abstract: A power supply and control system for a motor vehicle incorporating a plasma-assisted reactor for treatment of exhaust emissions and including a power source for supplying first and second output voltages.

Abstract: A reactor chamber forms part of an exhaust system of an internal combustion engine. Within the chamber are electrodes between which there is disposed a bed of active material through which, in use, the exhaust gases pass. In the presence of an electrical discharge, driven by an electrical voltage applied across the electrodes, the active material has a catalytic action in the reduction of nitrogenous oxides in the exhaust and also acts to remove hydrocarbons from the exhaust gases.

Abstract: A modular corona discharge reactor in which individual reactor chambers are arranged vertically and are grouped in serial pairs.

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: A reactor for non-thermal plasma assisted treatment of a gaseous medium incorporates at least one electrically conducting mesh filter element positioned so that gaseous medium passes therethrough. At least one dielectric barrier layer provides for a dielectric barrier type discharge, when an electrical power supply is connected to the electrodes to generate the plasma.

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: The onset of rolling contact fatigue in an object may be detected by measuring the residual stresses in the surface of the object, and monitoring changes in their magnitude or their direction. The values of residual stresses in the surface are those averaged over a depth that may be in the range say 0.1 mm to 8.0 mm, for example about 2.5 mm. For ferromagnetic objects such as rails, the method may utilise an electromagnetic probe. Prior to rolling contact fatigue the surface stresses are compressive, and the onset of rolling contact fatigue may be characterised by a marked decrease of the stress in the generally transverse direction.

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.