Abstract: Process for protecting a transparent optical substrate which is polymeric and has a vitreous transformation temperature and is selected from the group consisting of polycarbonate, polymethylmethacrylate, polystyrene acrylonitrile, crystalline polystyrene, polyimide, polyester, polyamide, polyvinyl chloride and glass, by deposition of an inorganic continous and transparent film consisting essentially of silicon, carbon, nitrogen, oxygen and hydrogen of the formula Si C.sub.x N.sub.y O.sub.z H.sub.t, in whichx is between 0 and 5y is between 0.3 and 0.8z is between 1.3 and 2.5t is between 0.5 and 1.2.A surface of the substrate is exposed to a plasma at a temperature below the temperature of vitreous transition of the substrate in the presence of precursors of Si, C, N, O and H is gaseous form, the precursor gas of the silicon being selected from the group consisting of SiH.sub.4, Si.sub.2 H.sub.6 and Si.sub.3 H.sub.

Abstract: A thin copper film is formed by CVD, by (a) forming a gas stream containing a copper halide, followed by introducing said gas stream into a CVD reaction chamber having a heated catalytic metal filament arranged herein, (b) introducing hydrogen gas into the CVD reaction chamber for activation of said hydrogen gas by the heated catalytic metal filament, and (c) carrying out the reaction between the copper halide contained in the gas stream introduced in step (a) and the hydrogen activated in step (b) near the surface of a substrate arranged within the CVD reaction chamber so as to deposit a thin copper film of copper on the substrate surface.

Abstract: Process for the gas treatment of a product in a confined treatment zone by a flow of an inert gas, such as nitrogen, wherein a gas flow which originates from a gas treatment containing a high proportion of nitrogen, becomes loaded with impurities such as: oxygen, and/or carbon dioxide, and/or water, and wherein the flow of gas which originates from the treatment undergoes at least substantially in part, a removal of the impurities in a separator of the adsorption or permeation type before being recycled as treatment gas, with addition of a compensating gas flow predominantly containing nitrogen. Application for example to the deoxygenation of liquids, in particular nutritious liquids, to the providing of inert conditions in ovens or storage enclosures for products such as electronic pieces, or in chambers used for preserving nutritious products in an atmosphere which is substantially free from oxygen.

Abstract: Process for preparing disilane, wherein a raw gas including monosilane, disilane, trisilane and impurities such as phosphine, hydrogen sulfide, arsine, disiloxane and higher siloxanes, undergoes a step of separation by distillation for the substantial elimination of the other compounds of silicon, except disiloxane, and the substantial elimination of phosphine, hydrogen sulfide and arsine impurities, wherein a final purification of the disilane takes place by selective adsorption on molecular sieves, in which one is a sieve of type 3 A and which is used for the elimination of the siloxanes and hydrogen sulfide and the other is a sieve of type 4 A for the elimination of phosphine and arsine.

Abstract: The invention relates to the treatment of a liquid with a gas. A gas injector, for example oxygen, is surrounded with a sheath to carry a flow of a liquid under treatment (for example lead) which is taken up and circulated by the pump. The end of the injector is thereby protected by moving away the bubbles of oxygen. Application for example in the refining of metals, for example non ferrous metals, food liquids, paper pulps and the production of sulfur.

Abstract: A light component of the compressed mixture is separated by permeation. The remaining heavy fraction is condensed with water, sub-cooled and expanded. The light component, cooled at the same temperature, is added to the sub-cooled condensate, and the whole is vaporized under low pressure to produce the required refrigeration.

Abstract: The pressure reducer body includes oppositely disposed bores for mounting inlet and outlet connecting devices, and the outer end of another bore defining a high pressure chamber in which the regulating valve is mounted, is adapted to receive a connecting device for a high pressure manometer defining a rest for a spring of a regulating valve which includes an annular truncated lining in which is force fittingly engaged a connecting rod between the regulating valve and the piston bounding the low pressure chamber. Applications to various pressure reducer arrangements for industrial use.

Abstract: A device for trapping gaseous compounds of refractory metals includes at least a vertically disposed elongated enclosure (1) in the form of a hollow cylindrical member (2), sealingly closed in its upper part via a cover (4), and having a hollow bottom (5) in its lower part. The enclosure is lined in the major part of the height of the member with a heat conductive lining (10) leaving within itself free vertical spaces from top to bottom; The enclosure includes a gas inlet opening (8) below the lower portion of the lining, a gas outlet opening (11) above the lining, a heater and heat insulation.

Abstract: A laser apparatus comprises a hollow waveguide containing a lasing gas composition; structure for directing radiation into the waveguide and for directing radiation out of the waveguide; and electrical exciting structure operatively associated with at least part of the waveguide. The waveguide defines a convoluted, continuously curved path having a helicoidal shape. The waveguide has a concave, non-closed transverse section with an open inner portion and is disposed within a gas-tight container containing the lasing gas composition. The waveguide is a laterally open groove formed internally in a cylindrical block disposed within the container.

Abstract: The support for the electrode has at its end a cavity at the bottom of which there is an emissive insert made of zirconium of hafnium. A portion of the support end around the insert has at least a portion of an electroconductive material axially projecting with respect to the insert. Application to plasma cutting torches ignition by short-circuit.

Abstract: To meet the requirement of a variable demand of gaseous oxygen, a constant flow of liquid oxygen is sent from the double distillation column into a container, and a variable flow of liquid oxygen is withdrawn therefrom, which is thereafter vaporized in a heat exchanger by condensation of a corresponding flow of incoming air. The liquefied air is stored in a second container, from which a constant flow of liquefied air is sent into the double column.

Abstract: The invention concerns the production of ceramic-metal multilayer components comrising effecting, after making up in the crude state, in particular by metallization and stacking of pre-cut raw ceramic bands, a simultaneous firing operation, termed cofiring, on the components under an atmosphere based on hydrogen or nitrogen or a mixture of hydrogen and nitrogen, having a regulated water vapor content at a temperature of first of all between 800.degree. C. and 1800.degree. C., and more precisely either at a moderately high temperature plateau between 800.degree. C. and 1300.degree. C. for certain ceramic materials such as codierite and metallic materials such as copper and nickel, or at a temperature plateau between about 1400.degree. C. and 1800.degree. C.

Abstract: Gaseous oxygen is produced under a medium pressure which is higher than atmospheric pressure, and lower than a so-called high pressure. The medium pressure may also vary with time after which gaseous oxygen is brought to the high pressure. Each of the adsorbers of a high pressure PSA (Pressure swing Adsorption) adsorption device, undergoes a cycle including the following stage: (a) a stage of first pressure surge from a low pressure of the low pressure cycle to the medium pressure, during which oxygen under a medium pressure is introduced at a first end or outlet end, of the adsorber; (b) a stage of second pressure surge up to the high pressure; (c) a stage of production under high pressure, during which a gas substantially below the high pressure containing at least one component which is more easily adsorbed than oxygen, is introduced through a second end, or inlet end of the adsorber the gas being for example air, the first end being open; and (d) a stage of decompression to the low pressure of the cycle.

Abstract: The column for the production of impure argon (2) is surmounted by an auxiliary column section (9) which is cooled to produce reflux by vaporizing poor liquid withdrawn from the head portion of the mean pressure column (3) and expanded. Application to the addition of an argon side column to an air distillation double column.

Abstract: These gases, specially adapted to the need of CO.sub.2 lasers, have a total purity less than 99.995%, a water content lower than 5 vpm and a total hydrocarbon content lower than 5 vpm.

Abstract: A process for manufacturing glass objects such as bottles, in which a cold fluid containing a cryogen is sprayed around and/or under the bottles in the region of the transfer tongs and/or of the standby table in order to accelerate the cooling of the bottles and improve the quality of the latter and the productivity of the manufacturing machines. This cooling may be accompanied by a localized, or complete quenching of the bottle.

Abstract: The air distillation double column (1,2) includes an apparatus for vaporizing oxygen and condensing nitrogen which comprises on one hand a running type main heat exchanger (7) which is partially immersed during stoppage of the equipment and on the other hand an auxiliary heat exchanger (20) which alone is responsible for liquid vaporization when the equipment is restarted.

Abstract: Heat treating metals by continuous longitudinal passage of metallic pieces in an elongated treating zone under controlled atmosphere having a high temperature upstream end where the controlled atmosphere comprises nitrogen and reducing chemical substances, such as hydrogen, possibly carbon monoxide, and a downstream cooling end under an atmosphere essentially formed by introducing nitrogen. In the high temperature upstream end, the nitrogen which constitutes the atmosphere is supplied by introducing nitrogen with a residual oxygen content not exceeding 5%, the reducing chemical substances being present at any moment in amounts at least sufficient to eliminate oxygen introduced with nitrogen. The nitrogen introduced in the downstream cooling end is substantially free of oxygen. Application of the process to the annealing of metallic pieces.

Abstract: An annealing treatment in a continuous furnace in which a flow of dense inert gas is injected in a rising duct and a descending duct, these flows being regulated by the analysis of hydrogen detected by a pressure controller acting on valves to achieve a minimum escape of hydrogen.

Abstract: Gaseous oxygen to be cooled passes through an exchanger which is cooled with compressed liquid nitrogen, at least a portion of the vaporized nitrogen which is warmed up in the exchanger being treated in a turbine and thereafter reintroduced into the exchanger. Application for example to the storage in liquid form of excess oxygen under pressure conveyed by a distribution network with variable load.