Abstract: A membrane gas generator, which contains: a) a feed stream compressor having a feed stream input, b) a heat source downstream of the feed stream compressor, and in fluid connection therewith, c) a heat accumulator downstream of the heat source, and in fluid connection therewith; and d) at least one membrane with a permeate side and a non-permeate side downstream of the heat accumulator.

Abstract: The conduits (1-4) of length L have a linear section S.sub.1 and contain a volumetric flow rate of nitrogen Q such that, to obtain a molar concentration of impurities upon out-gassing less than C.sub.max, Q/S.sub.1 is not less than 9.5.times.10.sup.-9 L/C.sub.max. The conduits are of stainless steel with a low carbon content, not electropolished and/or chemically treated. The joints (6, 7, 9, 11) between the conduits and/or the active members (5) are maintained externally in a neutral protective atmosphere confined in a sealed casing (8, 9 . . . ) Application particularly to electronic industries.

Abstract: A process for generating a nitrogen-enriched gas from a feed stream of atmospheric air or a mixture of nitrogen which is not continuously supplied to a membrane system, which membrane system comprises a non-permeate side and a permeate side, and being more permeable to oxygen than nitrogen, which process entails feeding the feed stream side of the membrane, and recovering an oxygen enriched gas being recovered on the permeate side of the membrane system while a nitrogen-enriched gas is recovered from the non-permeate side of the membrane, wherein a feed back of nitrogen gas or nitrogen- containing gas having an oxygen gas concentration lower than 21% is supplied to the non-permeate side of the membrane system during at least a part of the period of time where the air feed stream is not supplied to the membrane system thereby avoiding any substantial retrodiffusion of oxygen through the membrane system from the permeate side to the non-permeate side of the membrane during those periods of time where the feed s

Abstract: A process for producing a deposit of an inorganic and amorphous protective coating on an organic polymer substrate, the coating comprising compounds in the form of an oxide, nitride, carbide, or alloys thereof, by photosensitized decomposition in the gas phase, which comprises decomposing a gas medium by photosensitized decomposition, including precursors of the elements constituting the deposit of the inorganic and amorphous protective coating to be produced by photonic excitation of an impurity which has been previously introduced into the medium, said decomposition being adapted for producing an indirect transfer of energy to the molecules of the medium, thereby causing the decomposition and subsequent deposition of the these elements onto the substrate.

Abstract: To remove a layer of thermoplastic material, particularly of polyethylene, adhering to a substrate, particularly a strip of aluminum, there is directed against a region of the layer of thermoplastic material (2) a shaped jet (10) of hot inert gas, containing for example principally helium, to melt the thermoplastic material and the jet is displaced relative to the coated substrate to push back (11) the melted thermoplastic material. The gas or the gaseous between 300.degree. C. and 700.degree. C., by an electric resistance (20), adjacent the ejection nozzle (4).

Abstract: The plasma producing gas consists of a ternary mixture of helium, argon and hydrogen and contains at least about 10% hydrogen, typically 30 to 70% helium, 10 to 50% argon and 10 to 25% hydrogen, preferably 20% (.+-.5%) hydrogen. Use for the plasma projection of metallic oxide.

Abstract: A method of liquefying a low-boiling gas, in which gas is compressed to a high pressure, is cooled in heat exchange structure and is isenthalpically expanded to condense a portion of the same to liquid. The liquid being separated from residual gas and the residual gas is used to cool the heat exchange structure and is then recycled. A portion of the gas is compressed to an intermediate pressure between the high and low pressures, is isentropically expanded at a first temperature and is used to cool a relatively warm portion of heat exchange structure and is then recycled. A portion of the high pressure gas is isentropically expanded at a second temperature and used to cool a relatively cool portion of the heat exchange structure and then again isentropically expanded at a third temperature to that low pressure and returned through the heat exchange structure to cool the same and is then recycled.

Abstract: A projection device for depositing by projection a fused coating material onto a substrate. The projection device includes a projection nozzle having a central part defining a central passage for the coating material to be fused and projected. The central passage opening at a distal end thereof into a central orifice. The central part being fitted in a peripheral part. Ejection openings of ducts of oxycombustible mixture being distributed around the central orifice according to at least two series which are alternatingly offset from one another with respect to a main axis of the nozzle. The ducts include channels which are milled in the periphery of the central part. The carrier gas contains between 1 and 10% oxygen with the remaining portion consisting of nitrogen. The carrier gas being supplied by a unit for the separation of inert gas from air by adsorption or permeation. The projection device is particularly suited for the formation of the anti-corrosive deposits based on zinc.

Abstract: A process for the cryogenic separation of mixtures containing oxygen to obtain a produce having a high concentration of oxygen. In this process, a heat and material exchange occurs in counter-current between a descending liquid and a rising gas in at least one transfer zone including a bundle of organized linings consisting of cross-undulated metallic layers. In at least one transfer zone where the concentration of oxygen is higher than 98%, the layers are made of a sheet of aluminum having a thickness between 0.3 and 1 mm. Additionally, the bundles of layers have a specific surface lower than 400 m.sup.2 /m.sup.3.

Abstract: The compression circuit for a gaseous fluid, typically helium, which is present in a first container at a pressure lower than 20 hPa and a temperature lower than 4.2K is compressed by means of a plurality of compressors mounted in series, at least one heat exchanger being disposed in the chain of compressors and cooled through said fluid at a temperature higher than the temperature of the fluid in the first container, said fluid originating from a second fluid container which is associated with a refrigerating cycle. Application for example to devices for cooling supraconductor elements.

Abstract: A membrane nitrogen generator adapted to deliver a flow rate of nitrogen gas having a purity at least equal to P.sub.0, which contains:a) a source of compressed nitrogen containing gas having a purity lower than P.sub.0, the source having a maximum flow rate Fm.sub.1 ;b) a varyer connected to the source, which is adapted to vary the flow rate of the source between Fm.sub.1 and 0;c) a nitrogen membrane fed by the source which is capable of delivering a low purity nitrogen gas having a purity P.sub.1, which purity is lower than P.sub.0 at the maximum flow rate Fm.sub.1 ;d) a source of high purity compressed nitrogen gas having a purity which is greater than P.sub.0 which has a controllable flow rate of from 0 to a maximum flow rate value of Fm.sub.2 ;e) a mixer; andf) a purity controller.

Abstract: This device comprises a packet of corrugated plates (3) each disposed in a generally vertical plane, the corrugations being oblique and descending in opposite directions from one plate to the following plate. Each corrugation valley (5) having a lower end opening out laterally includes an projecting obstacle (7) in the vicinity of this lower end.Application in air distillation columns.

Abstract: The valve slide, which is slidably mounted in a housing of a valve member, comprises a central part including a shaped part cooperating with a first joint between a first zone and a second zone of the housing, and an end part including a peripheral joint between the second zone and a third zone, the three zones being in communication with three respective circuits of a pneumatic distribution block.

Abstract: The selective adsorption of nitrogen from air is used in a system including a number of adsorbers, to give oxygen enriched gas at elevated pressure, the adsorber is regenerated by depressurization under atmospheric pressure with a pump and by repressurization with oxygen enriched gas. The pumping duration is at most equal to the duration of the production step.

Abstract: The invention relates to a method of forming a silicon diffusion and/or overlay coating on the surface of a metallic substrate comprising the steps of introducing the sample into a cold wall Low Pressure Chemical Vapor Deposition (LPCVD) enclosure, evacuating the enclosure up to a pressure P.sub.1 which is lower than 0.5 Torr, maintaining said pressure P.sub.1 while heating up said sample to a temperature which is comprised between about room temperature and about 300.degree. C., bringing under same pressure P1 the sample to the CVD temperature comprised between about 50.degree. C. and 1000.degree. C., introducing a gas or gas mixture comprising at least one silicon hydride gas, maintaining the pressure inside the enclosure between about 0.

Abstract: Process for the purification of a gas containing selectively adsorbable impurities, of the type using several adsorbers with, for each adsorber, a cycle comprising the following operating phases which are offset from one adsorber to the next timewise by a fraction 1/n of the duration of the cycle in which n is the number of adsorbers, the cycle comprising substantially isobaric production at a high pressure of the cycle, this production comprising the admission of impure gas to be treated into an adsorber at a first end of the adsorber with circulation of this gas in the adsorber and simultaneous withdrawal from a second end of the adsorber of purified gas, the direction of flow in the adsorber from the first end to the second end being cocurrent and the opposite direction being countercurrent; regeneration of the adsorber comprising a decompression of the adsorber to a low pressure of the cycle, this decompression comprising at least one stage in which a residual gas is withdrawn countercurrent from the adso

Abstract: The different compartments of the preserving vessel are sequentially supplied with a controlled atmosphere by means of a first permeator providing a controlled atmosphere with an oxygen content of about 2% for the step of loading the compartment, then by means of an another separator providing a controlled atmosphere with an oxygen content which does not exceed 1% for a phase of extended conservation. The separators are typically of the type with a membrane and are supplied through a group of common compression, and the oxygen contents of the gases which are provided are controlled by means of flow limiters located downstream.

Abstract: In the process for the production of oxygen by adsorption, the following combination of steps are used: the number of adsorbers is at least three; the time of pumping y under sub-atmospheric pressure during step b) is higher than dephasing T/n, and at least equal to the time x of the production step; the phase of pumping of the column of adsorbent material is carried out by using on said adsorption column successively at least two systems of pumping wherein one is in operation from the start of the pumping operation, another one is adapted to operate until pumping is over.

Abstract: Multilayer coating for polycarbonate substrate used as glass substitute essentially consisting of silicon, carbon, nitrogen, oxygen and hydrogen, characterized by a first anti-ultra-violet layer consisting of silicon, oxygen and/or nitrogen, carbon and hydrogen, according to formula:SiCx.sub.1 Oz.sub.1 Ht.sub.1,where x.sub.1 +z.sub.1 +t.sub.1 is between 1,2 and 1,5SiCx.sub.1 Ny.sub.1 Ht.sub.1,where x.sub.1 +y.sub.1 +t.sub.1 is between 1,2 and 1,5SiCx.sub.1 Ny.sub.1 Oz.sub.1 Ht.sub.1,where x.sub.1 +y.sub.1 +z.sub.1 +t.sub.1 is between 1,2 and 1,4and t.sub.1 is always between 0,1 and 0,7; x.sub.1 before y.sub.1 and/or z.sub.1 is small, so that the limit of optical absorption is concentrated at about 350 nm; the second transparent hard layer consists of silicon, oxygen, nitrogen, carbon and hydrogen, of formula SiCx.sub.2 Ny.sub.2 Oz.sub.2 Ht.sub.2, where, in particular:either y.sub.2 =0, z.sub.2 is between 1,7 and 2,0, t.sub.2 is between 0,1 and 0,7, x.sub.2 before z.sub.2 is small;or y.sub.

Abstract: There is produced by an air distillation apparatus (4) a desired fraction of air from the stream of air leaving at least one blower (3) of the blast furnace, and there is sent to the blast furnace the oxygen produced by this distillation apparatus. The distillation apparatus comprises an air/liquid oxygen mixing column which operates at about 1 bar above the delivery pressure of the blower (3) and which directly produces the oxygen for enriching the air.