Abstract: Metal objects are treated by anodizing (P, SE) the metal object in contact with an acidic solution, and then subjecting the anodized metal object to a reversed voltage (VR). The anodizing is performed in two stages, firstly to passivate (P) with the formation of a surface layer, and secondly to form pits in this surface layer (SE). The second stage (SE) of anodizing is performed at a lower voltage than the first stage (P). After the reversed voltage step (VR) the metal object is then contacted with a biocidal metal-containing solution. Biocidal metal is absorbed into the surface of the metal object, resulting in improved biocidal properties. The lower voltage of the second stage anodizing (SE) results in reduced processing time.

Abstract: Metal objects are treated by anodising (P, SE) the metal object in contact with an acidic solution, and then subjecting the anodised metal object to a reversed voltage (VR). The anodising is performed in two stages, firstly to passivate (P) with the formation of a surface layer, and secondly to form pits in this surface layer (SE). The second stage (SE) of anodising is performed at a lower voltage than the first stage (P). After the reversed voltage step (VR) the metal object is then contacted with a biocidal metal-containing solution. Biocidal metal is absorbed into the surface of the metal object, resulting in improved biocidal properties. The lower voltage of the second stage anodising (SE) results in reduced processing time.

Abstract: Metal objects are treated by anodising (P, SE) the metal object in contact with an acidic solution, and then subjecting the anodised metal object to a reversed voltage (VR). The anodising is performed in two stages, firstly to passivate (P) with the formation of a surface layer, and secondly to form pits in this surface layer (SE). The second stage (SE) of anodising is performed at a lower voltage than the first stage (P). After the reversed voltage step (VR) the metal object is then contacted with a biocidal metal-containing solution. Biocidal metal is absorbed into the surface of the metal object, resulting in improved biocidal properties. The lower voltage of the second stage anodising (SE) results in reduced processing time.

Abstract: Metal implants (10) are treated by anodising the surface (11, 12) in contact with an electrolyte, and then briefly subjecting the anodised surface to a reversed voltage. During a first anodising stage the surfaces are passivated, while during a subsequent anodising stage pits are formed in the passivating surface layer. Rough portions (15) of the surface, in particular portions produced by plasma spraying of metal powder, are sealed with a watertight cover (20) during at least part of the anodising process. After rinsing, biocidal metal ions are subsequently absorbed into the surface of the implant. This provides the implant with biocidal properties. The use of the cover (20) enables a more uniform geometric distribution of biocidal metal ions to be achieved.

Abstract: Metal objects are treated by anodising the metal object in contact with an acidic solution, and then subjecting the anodised metal object to a reversed voltage (compared to the anodising voltage). The thus-treated metal object is then contacted with a biocidal metal-containing solution. Biocidal metal is deposited on the surface of the metal object, resulting in improved biocidal properties.

Abstract: A process and apparatus are provided for producing hydrogen from a hydrocarbon fuel by combining the fuel with a gas comprising both oxygen and steam, and passing the resulting mixture through a plasma generated by a microwave plasma generator between opposed electrodes. At least one of the electrodes defines a duct for outflow of gaseous material from the vicinity of the plasma, and the gas mixture emerging from the outflow duct contains hydrogen. The fuel undergoes partial oxidation and steam reforming, the reactions being initiated by the plasma rather than by a catalyst.

Abstract: Metal implants (10) are treated by anodising the surface (11, 12) in contact with an electrolyte, and then briefly subjecting the anodised surface to a reversed voltage. During a first anodising stage the surfaces are passivated, while during a subsequent anodising stage pits are formed in the passivating surface layer. Rough portions (15) of the surface, in particular portions produced by plasma spraying of metal powder, are sealed with a watertight cover (20) during at least part of the anodising process. After rinsing, biocidal metal ions are subsequently absorbed into the surface of the implant. This provides the implant with biocidal properties. The use of the cover (20) enables a more uniform geometric distribution of biocidal metal ions to be achieved.

Abstract: Metal objects are treated by anodising (P, SE) the metal object in contact with an acidic solution, and then subjecting the anodised metal object to a reversed voltage (VR). The anodising is performed in two stages, firstly to passivate (P) with the formation of a surface layer, and secondly to form pits in this surface layer (SE). The second stage (SE) of anodising is performed at a lower voltage than the first stage (P). After the reversed voltage step (VR) the metal object is then contacted with a biocidal metal-containing solution. Biocidal metal is absorbed into the surface of the metal object, resulting in improved biocidal properties. The lower voltage of the second stage anodising (SE) results in reduced processing time.

Abstract: Metal objects are treated by anodising the metal object in contact with an acidic solution, and then subjecting the anodised metal object to a reversed voltage (compared to the anodising voltage). The thus-treated metal object is then contacted with a biocidal metal-containing solution. Biocidal metal is deposited on the surface of the metal object, resulting in improved biocidal properties.

Abstract: A process and apparatus are provided for producing hydrogen from a hydrocarbon fuel by combining the fuel with a gas comprising both oxygen and steam, and passing the resulting mixture through a plasma generated by a microwave plasma generator between opposed electrodes. At least one of the electrodes defines a duct for outflow of gaseous material from the vicinity of the plasma, and the gas mixture emerging from the outflow duct contains hydrogen. The fuel undergoes partial oxidation and steam reforming, the reactions being initiated by the plasma rather than by a catalyst.

Abstract: A microwave plasma generator including field-enhancing electrodes consisting of opposed laminae (108,109) with a gap (110) between them orthogonal to the direction of propagation through the plasma generator of microwave radiation. Gas inlet (106) and outlet (107) ports are arranged so that a gaseous medium to be excited into the plasma state passes through the gap (110).

Abstract: A plasma reactor (11) of the silent discharge or dielectric barrier type for treatment of a gaseous medium is provided with a layer of material (34) positioned to present a surface extending along at least part of the length of the gas flow path. Particulates or selected species are entrapped on the surface. A preferred electrode arrangement provides surface discharge in the plasma at the surface of the layer of material.

Abstract: A plasma assisted reactor for the removal of carbonaceous combustion products or for simultaneous removal of carbonaceous products and nitrogen oxides from the exhaust emissions from an internal combustion engine, wherein the reactor includes a gas permeable bed made at least primarily of active materials comprising perovskite or vanadate.

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 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: 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 microwave plasma generator including field-enhancing electrodes consisting of opposed laminae (108,109) with a gap (110) between them orthogonal to the direction of propagation through the plasma generator of microwave radiation. Gas inlet (106) and outlet (107) ports are arranged so that a gaseous medium to be excited into the plasma state passes through the gap (110).

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.