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 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 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: 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: 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: 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 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: 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: The invention is concerned with a process of the type in which the air to be treated, from which water and CO.sub.2 have been removed and which has been cooled at about its dew point, is injected at the base of the mean pressure column of the double column. A first fraction of rich liquid, withdrawn from the bottom of the mean pressure column is expanded and sent into a head condenser of a column for the production of impure argon connected to the low pressure column of the double column. A second fraction of rich liquid, withdrawn from the lower portion of the mean pressure column, is expanded and sent as reflux into the low pressure column. According to the invention, a second fraction of rich liquid is withdrawn from an intermediate point of the mean pressure column and a residual gas from the apparatus is formed from at least a portion of the rich liquid withdrawn from the bottom of the mean pressure column.

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.

Abstract: Methanol is catalytically cracked (at 4) then the essential portion of the components other than CO is removed by washing with water (at 5), selective adsorption (at 7) and permeation (at 8). The process and apparatus has application to the production of moderate quantity of carbon monoxide.

Abstract: Process for thermal treatment of metals by passage of metallic pieces into an elongated zone under a controlled atmosphere, having an upstream section at an elevated temperature, where the controlled atmosphere comprises nitrogen and reductive chemicals, particularly hydrogen, possibly carbon monoxide; and a downstream section at a lower temperature under a controlled atmosphere. The invention is characterized by the fact that in the upstream section at an elevated temperature, the atmosphere comprises nitrogen having a residual content of oxygen between 0.5% and 5% produced by separation of air using permeation or adsorption techniques. The reductive chemicals are present at all times in a content at least sufficient to eliminate the oxygen admitted with the nitrogen.

Abstract: The invention relates to a process of making a high purity silicide target comprising the steps of providing a substrate in a CVD enclosure, evacuating said enclosure up to a pressure P1 which is at least equal to or smaller than 5.times.10.sup.-5 Torr, heating the substrate at a temperature T1, which is at least equal to or greater than 20.degree. C., injecting in said enclosure a refractory metal halide MXm having a purity, as far as metallic impurities are concerned, greater than 5N (99,999%) and a silicon hydride having a purity, as far as metallic impurities are concerned, greater than 6N (99,9999%) setting the pressure in the enclosure between about 0.01 Torr and the atmospheric pressure while maintaining the temperature in the CVD enclosure between about 20.degree. C.