Abstract: A permanent magnet essentially consisting of in weight percent, 60% to 68% at least one transition element by weight, 30% to 38% at least one rare earth element by weight, 0.1% to 1.5% nitrogen by weight, and 0.8% to 1.5% boron by weight is disclosed. A method for producing the permanent magnet containing at least one rear element, at least one rare earth element, nitrogen and boron includes melting, cooling, milling, magnetizing, and compacting the transition element, the rare earth element and boron to form a green compact, and then sintering the green compact in nitrogen atmosphere having a constant partial pressure for 1 to several hours to form the permanent magnet.

Abstract: This invention relates to a method for producing surface-treated magnetic power for high record density magnetic recording medium which has excellent dispesibility and high filling density and surface smootheness.This invention provides a method for producing surface-treated magnetic powder characterized by treating magnetic powder with at least one functional group of the epoxy group, carboxyl group, hydroxyl group, thiol group and amino group and with hydrocarbon group having more than eight methylene chains.

Abstract: A rare earth-iron magnet consisting of, by atomic percent, 10 to 16% Nd, 5 to 10% B, 0.1 to 1% V, 0.1 to 1% oxygen and the balance being Fe.

Abstract: The present invention relates to a process for the production of a stainless steel with a high elastic limit and a high breaking load, with a martensite ferrite two-phase structure exhibiting good malleability and good abrasion resistance, in which the steel of the following weight composition:carbon lower than 0.10%chromium between 16 and 20%nickel between 0.2 and 2%manganese lower than 2%copper lower than 2%the remainder being iron and impurities which are inherent in the method of production, is subjected to a quenching after being raised to a temperature of between 800.degree. to 1200.degree. C., and at least one cold rolling to a content of more than 15%.The present invention also relates to a stainless steel obtained by this process.

Abstract: A material for electric heater element sheathing, which has good weldability, is oxidation- and corrosion-resistant, and forms an eye-pleasing dark gray or black surface oxide, consists essentially of, by weight, from about 8.75-15.5% nickel, about 19.5-21.0% chromium, about 0.30-0.50 manganese, about 0.50-2.0% silicon, about 0.25-0.60% aluminum, about 0.25-1.0% titanium, up to about 0.05% carbon, up to about 0.005% sulfur, up to about 0.75% copper, up to about 1.0% cobalt, up to about 1.0% molybdenum, up to about 0.02% phosphorus, about 0.001-0.015% calcium plus magnesium and remainder essentially iron, wherein the Ferrite Number is between 1 and 15.

Abstract: A cast hypereutectic Al-Si alloy with from 12-15% Si, having excellent wear resistance and machinability, improved fatigue strength and good levels of ambient and elevated temperature properties is provided, as well as a method of producing such alloy. The alloy and a melt used in the method contains Sr in excess of 0.10% and Ti in excess of 0.005%, the alloy further comprising: Cu 1.5 to 5.5%, Ni 1.0 to 3.00%, Mg 0.1 to 1.0%, Fe 0.1 to 1.0%, Mn 0.1 to 0.8%, Zr 0.01 to 0.1%, Zn 0 to 3.0%, Sn 0 to 0.2%, Pb 0 to 0.2%, Cr 0 to 0.1%, Na 0 to 0.01%, B (elemental) 0.05% maximum, Ca 0.003% maximum, P 0.003% maximum. Others 0.05 maximum each, the balance, apart from incidental impurities, being Al. The level of Sr in excess of 0.10% and Ti in excess of 0.

Abstract: The present invention relates to an aluminum alloy for fins of heat exchangers such as of automobile radiators and evaporators comprising 0.3 to 1.0% by weight of silicon, 0.3 to 3.0% by weight of iron, and the balance of aluminum and unavoidable impurities, which is readily workable for a fin (or readily corrugated), and is less deformed by brazing heat, and yet has improved thermal conductivity after the brazing.

Abstract: A process for working .beta. titanium alloy comprises the steps of first elongating the alloy at a temperature not higher than a .beta. transus temperature and at a working ration of 30% or more. Next, conducting a subsequent aging treatment. Then, elongating the alloy at a temperature not higher than the aging treatment temperature and at a working ratio of 70% or more when combined with that in the first step for elongating. Then a recrystallization treatment is carried out at a treating temperature not higher than the .beta. transus temperature or isothermal working is carried out within a temperature range of the .beta. transus temperature minus 200.degree. C. to the .beta. transus.

Abstract: A pneumatic safety tire, of the type preferably having a section height of five inches or greater, having a pair of crescent shaped elastomeric reinforcing members located between the innerliner and side wall and extending from adjacent the tread shoulders to at least the apex of the bead fillers of the tire. A pair of bias reinforcing plies are located between the elastomeric reinforcing members and the side walls of the tire and extend along the side walls from adjacent the tread shoulders to below the top most turn-up ends of the body ply. The elastomeric reinforcing members preferably are similar in composition to that of the bead fillers and have a low hysteresis value preferably within the range of 0.03 and 0.11, a high modulus preferably within the range of 2600 psi and 2800 psi and a Shore A hardness preferably within the range of between 85 and 91.

Abstract: Prior to the press-contact between a pattern-transferring flat plate and a transfer-receiving flat plate, at least one of these flat plates is moved to a predetermined position to effect the positioning therebetween, while the positional relation between the pattern-transferring flat plate and the transfer-receiving flat plate is optically observed, and thereafter these flat plates are sequentially press-contacted to each other from an end of the flat plates. Therefore, there is no positional difference between the flat plates which have been correctly positioned, and further the adhesion strength between the transfer pattern and the transfer-receiving flat plate is uniform.

Abstract: In a mailing machine base including structure for feeding an envelope, having a body and a flap, in a downstream path of travel, and including structure for deflecting the flap, a process for selectively guiding an envelope into and out of engagement with the flap deflecting structure, the process comprising the steps of, providing a baffle upstream from the flap deflecting structure, providing electromechanical structure for moving the baffle, providing a microprocessor for controlling the baffle moving structure, providing a resettable timer having a predetermined time out time interval, operating the baffle moving structure to move the baffle into the path of travel for guiding an envelope fed therein out of engagement with the flap deflecting structure and operating the baffle moving structure to move the baffle out of the path of travel for the time interval for guiding an envelope fed in the path of travel during the time interval into engagement with the flap deflecting structure.

Abstract: The present invention provides a pressure sensitive adhesive for a tile-like floor material wherein the adhesive includes a polymer A having a mean particle diameter of from 0.05 to 4 .mu. and a polymer B having a mean particle diameter of from 5 to 150 .mu. and in combination therewith, the polymer B being obtained by aqueous suspension polymerization in the presence of a partially saponified polyvinyl alcohol and being lower than the polymer A in glass transition point, and a method of installing the tile-like floor material which employs the adhesive.

Abstract: Central is a nonstretchable, high strength thread that extends transverse to stretching, either of individual heat recoverable strands or of an embedding layer. The thread is either placed across plural heat recoverable strands, or plural threads are individually wrapped around the strands, or there is a plurality of helices on thermoplastic strings in a heat recoverable embedment, with further transverse high strength threads being interwoven with the helices.

Abstract: A covering sheet, which is preferably already marbled or veined, is subjected to a scraping operation resulting in the formation of shavings. The shavings are deposited on the previously scraped sheet and made to adhere thereto again, thus producing a substantially non-directional grain effect.

Abstract: The invention is a process for forming a hollow tubular member with an integral attachment end fitting.

Abstract: Honeycomb materials having areas or volumes possessing different physical properties then the remainder of the honeycomb are prepared in a continuous process without requiring machining operations.

Abstract: A levee gate and the process for the production thereof. The levee gate of the invention includes a rectangular sheet of thermoplastic material with a rectangular sleeve located on one edge of the thermoplastic material, the rectangular sleeve being a portion of the rectangular sheet fused to the rectangular sheet. The process for the production of the levee gate includes extruding a cylindrical tube of thermoplastic material, inflating the cylindrical tube as it is extruded to provide an inflated length of tube, flattening the inflated length of tube without fusing the opposed walls of the tube to each other, and continuously fusing a portion of the opposed walls together to form a seam.

Abstract: A method of transfer molding of inks onto a reptile skin wherein the tanned reptile skin is printing directly thereon in one or two passages with a transfer machine by using sublimatic inks to form a drawing and then to transfer print onto a bottom colored in advance; the same bottom can be previously colored in different way, by immersion, atomization or smearing, and after the transfer molding is carried out, a fixing treatment is made in order to protect the drawings from the atmospheric agents, which can be carried out through atomization by means of casein products and then the treatment is completed by lustering, and the bottom can be fitted with an adhesive film, or other bonding material in order to protect the printed bottom with a transparent one which maintains its visualization and provides a glossy surface with a hot color effect.

Abstract: An in-situ deep-ultraviolet light generation module (126) for photon-assisted processing of semiconductor wafers (44) comprises a process environment space (152) for photochemical processing applications. Process gas injection space (182) receives reactive process gases and injects them into process environment space (152). Plasma fill space (124) receives a plasma (120) and may direct plasma (120) away from or into the process environment space (152) according to the presence or absence of control gas (160) flow. Control gas space (174) and flow/pressure switch space (154) receive control gas (160) to selectively permit deep-ultraviolet photons or plasma to reach process environment space (152) and interact with wafer (44) for photo-enhanced or plasma-enhanced wafer processing.

Abstract: An ashing apparatus of the vertical type comprises a reaction tube erected in the vertical direction to house therein a plurality of semiconductor wafers, an inner tube arranged in the reaction tube to enclose the semiconductor wafers and having a plurality of holes through which activated radicals in plasma can be selectively passed, a reaction gas supply pipe for supplying reaction gases into a space between the reaction tube and the inner tube, and plasma generating electrode unit located outside the reactor tube to generate plasma of the reaction gases only in the space between the reaction tube and the inner tube.

Abstract: The present invention provides a laminating apparatus comprising a sheet transporter for transporting a sheet, a laminating film transporter for transporting at least one laminating film in such a manner that the laminating film is superposed with at least one surface of the sheet transported by the sheet transporter. A pressing mechanism means presses the sheet and the lamenting film or films in a mutually superposed state, a heater heats the laminating film, heat capacity detector detects the heat capacity of at least one of the laminating film or films and the sheet, and a controller controls at least one of the heater and the laminating film transporter, according to a detection signal from the heat capacity detector.

Abstract: In the apparatus of this invention a plurality of cylindrical matrices 2 are used to form tubular sleeves of elastomeric material to be later cured and cut into short segments to be used as belts, usually toothed belts. A coiling station 8 places a reinforcing fiber helically around the entire length of the sleeve. The matrix having the coils is then turned to a vertical position by a transfer member 28 and transferred, by means of an adjacent rotating platform 6 to a winding station 9 for application of a sheet of elastomeric material over the thread. The matrix having the completed but uncured sleeve is then placed back on the rotating platform. The coiling station and the winding station each have a tilting member 34 or 43 with two pairs of arms 39 or 52 so that while a completed matrix is swung out of the working position, a fresh matrix is swung into position.

Abstract: Cold-stretchable sheet material is isostatically formed at an operating temperature beneath the softening temperature of the sheet material by means of a fluid pressure medium at a pressure of more than 20 bars so as to produce a deep-drawn formed plastics piece. Forming may take place abruptly. The sheet to be formed may be provided with a coating such as an ink imprint. The resulting thin-walled deep-drawn piece may be backed and reinforced by injecting further plastics material.

Abstract: A method of producing sheets of crystalline material is disclosed, as well as devices employing such sheets. In the method, a growth mask is formed upon a substrate and crystalline material is grown at areas of the substrate exposed through the mask and laterally over the surface of the mask to form a sheet of crystalline mateGOVERNMENT SUPPORTWork described herein was supported by the U.S. Air Force.

Abstract: Floating zone refining or crystal growth is carried out by providing rapid relative rotation of a feed rod and finish rod while providing heat to the junction between the two rods so that significant forced convection occurs in the melt zone between the two rods. The forced convection distributes heat in the melt zone to allow the rods to be melted through with a much shorter melt zone length than possible utilizing conventional floating zone processes. One of the rods can be rotated with respect to the other, or both rods can be counter-rotated, with typical relative rotational speeds of the rods ranging from 200 revolutions per minute (RPM) to 400 RPM or greater. Zone refining or crystal growth is carried out by traversing the melt zone through the feed rod.

Abstract: A glass passivation layer is deposited, densified and polished. Thereby an underlying wafer containing substantially defined devices is exposed to a temperature cycle that is sufficient for densification of the glass, and no more. Reflow and its attendant additional temperature cycle are thereby avoided, allowing for smaller, faster devices to be fabricated. Increased control over the ultimate thickness of the glass layer is also provided.

Abstract: Disclosed is a process for etching a film of boron nitride with high selectivity to a layer of silicon dioxide or silicon nitride. The process involves exposing the film to a plasma formed from a mixture of an oxygen-containing gas, such as oxygen, and a small amount of a fluorine-containing gas, such as CF.sub.4. The process provides a high etch rate and anisotropic profiles, as well as good uniformity.

Abstract: A process for etching a silicon substrate to form a feature such as a V-groove, utilizes a coating formed of an alkaline resistance polymer. A preferred polymer is poly(benzocyclobutene) resin. The coating is applied to the substrate and removed form a selected region whereupon the underlying silicon is etched with an alkaline solution. In one aspect, an optical fiber is inserted in the etched groove and coupled to an optical waveguide embedded within the coating.

Abstract: A solution is described for the chemical processing of beta phase-containing titanium alloys. The solution contains HNO.sub.3 and HF, along with a small but effective amount of copper, ruthenium, rhodium, palladium, osmium, iridium, platinum or gold to reduce hydrogen absorption, ammonium formate and citric acid to increase the milling rate, and a surfactant to ensure a satisfactory milled surface.

Abstract: A dry etching method for etching an aluminum (Al) based layer for effectively combatting the after-corrosion in accordance with three aspects. In the first aspect, while a resist mask and chlorine based gas as known per se are used, S.sub.2 F.sub.2 is used during etching of the barrier metal layer. In this manner, residual chlorine in a carbonaceous polymer as a sidewall protection material or a resist mask is replaced by fluorine, whilst sulfur yielded from S.sub.2 F.sub.2 under conditions of discharge dissociation is deposited to provide for sidewall protection effects. In the second aspect, a SiO.sub.2 mask and an S.sub.2 Cl.sub.2 etching gas are used. Since the sidewall protection material is solely sulfur yielded from S.sub.2 Cl.sub.2, it becomes possible to avoid the effects of the residual chlorine. In the third aspect, an neutral Ar beam is irradiated at a suitable stage in the etching process for increasing the resistance of the SiO.sub.

Abstract: A process for the surface treatment of moldings based on liquid crystalline polymers with acidic or alkaline reagents includes using the reagents in a solvent which is an organic solvent to an extent of not less than 60% by weight.

Abstract: The centrifugal evaporator-concentrator includes a central tubular pivot (18) surmounted by a nozzle (35) and constituting the pivot axis of a rotor (9) rotating in a vessel (8) closed by a cover (11). With the rotor rotating in the partial vacuum created by a vacuum pump (33), a small quantity of gas or air is temporarily and periodically admitted into the vessel, this gas being heated by a heating resistor (38) inside the vessel for the purpose of heating by conduction the specimens to be concentrated and of accelerating the rate of evaporation.

Abstract: A method for removing laser printer and xerographic toner, ink or the like from paper to be recycled comprising pulping the paper to be recycled with water to produce a paper pulp slurry with a consistency of between about 1% and 20%, adjusting the pH of the slurry to between about 6 and about 13, adding between about 0.3 and about 5.0 wt. %, based on the dry weight of the paper, of a surfactant to the slurry, the surfactant having the formula R.sup.1 --R.sup.2 --R.sup.3, wherein R.sup.1 and R.sup.3 are each selected from the group consisting of rosins, rosin dimers and mixtures of rosins and rosin dimers and R.sup.2 is a polyethylene glycol (PEG) having a molecular weight of between about 220 and about 660 Da, and adding between about 0.01 and about 5.0 wt. % of polyacrylic acid to the slurry, maintaining the slurry at a temperature of between about 30.degree. C. and about 120.degree. C.

Abstract: Unbleached pulp is combined with an aqueous alkaline solution while in a state of low consistency to distribute a first amount of alkaline material substantially uniformly throughout the pulp. The consistency of the pulp is then increased to above about 18%, and the high consistency alkali containing pulp is then treated with oxygen to effect delignification. The total amount of alkaline material applied to the pulp is between 0.8 and 7% by weight of oven dry pulp. High strength, low lignin pulps are subsequently formed which may be further bleached to high brightness with reduced amounts of chemicals.

Abstract: A process for oxygen bleaching fibrous cellulose pulp is described in which the pulp passes a first delignification zone with a predetermined low temperature and a second delignification zone with a predetermined high temperature which is higher than that in the first delignification zone. The pulp is fed through a first vertical reactor containing said first delignification zone with low temperature, and thereafter through a second vertical reactor containing said second delignification zone with high temperature. The temperature in the first delignification zone is either maintained at the temperature that the pulp entering for bleaching has acquired during a previous treatment before the oxygen bleaching, or as required is adjusted by the controlled supply of steam to a mixer disposed in the pipe before the first reactor. The temperature in the second delignification zone is adjusted by the controlled supply of steam to a mixer disposed in the pipe between the two reactors.

Abstract: Tissue paper webs useful in the manufacture of soft, absorbent products such as napkins, facial tissues, and sanitary tissues, and processes for making the webs. The tissue paper webs comprise papermaking fibers, a quaternary ammonium compound, a polyhydroxy plasticizer, and a temporary wet strength resin. The process comprises a first step of forming an aqueous papermaking furnish from the above-mentioned components. The second and third steps in the basic process are the deposition of the papermaking furnish onto a foraminous surface such as a Fourdrinier photo-polymer wire and removal of the water from the deposited furnish. An alternate process involves the use of the furnish containing the aforementioned components in a papermaking process which will produce a pattern densified fibrous web having a relatively high bulk field of relatively low fiber density in a patterned array of spaced zones of relatively high fiber density.

Abstract: A wire-link belt 1, 41 comprises a first and second, opposite belt side 32, 34; 61, 64, the first side supporting a moving length of material or a web of paper 33, 62, said wire-link belt further comprising a plurality of interlinking wire coils 2, 3, 4, 5; 42,43 consisting alternatingly of end arcs 16, 17, 18, 19; 49, 50 and coil-turn legs 10, 11, 12, 13, 14, 15; 45, 46, 47, 48 connecting them and coupled in hinging manner by means of slip-through wires. To reduce slippage between the moving length of material or web of paper 33, 62 and the wire-link belt 1, 41 on one hand and buckling or elongation of said length of material on the other hand, the support of the wire coils 2, 3, 4, 5; 42, 43 at the slip-through wires is such that the wire coils 2, 3, 4, 5; 42, 43 each hinge about axes offset relative to the center plane of the wire-link belt 1, 41 towards its first belt side 32, 61.

Abstract: The processor is of the type incorporating horizontal, concentric, co-extensive inner and outer tubular members which rotate together. The processor is modified in the following respects:The front end of the inner tubular member is circumferentially corrugated and may be provided in the form of a plurality of parallel tubes arranged in a ring array, to thereby increase the shell area to promote heat transfer through the tube walls;Means are provided for interconnecting the tubular members, which means can accommodate differing rates of thermal expansion and;a rock recycle tube assembly is provided to recover oversize material leaving the corrugated portion of the inner tubular member and reject it from the processor.

Abstract: A system for continuously recovering renewable volatile compounds by boiling points from waste organic solvent with minimum energy loss, and an improved thin membrane distillation apparatus for efficient distillation of renewable volatile compounds from waste organic solvent and enforced discharge of the residue or sludge. The waste treatment system includes a thin membrane distillation apparatus, a cooling unit, a first distillation unit, and a second distillation unit connected in this sequence. Alternatively, the system includes two thin membrane distillation apparatus, a reduced pressure distillation unit, and a normal pressure distillation unit connected in this sequence. The thin membrane distillation apparatus includes a decompression chamber, a waste inlet, an outlet for volatile compound, an air-tight chamber, and a breaking mechanism with a screw head movable into the air-tight chamber.

Abstract: A water distiller includes a base having a front portion for supporting a container and having a housing extended upward from the rear portion, a vessel disposed in the housing for containing water, a heater disposed below the vessel for heating the water contained in the vessel into steam, and an arm extended forward from the housing. A radiator is disposed in the arm for cooling the steam flowing into the arm, and the condensed water is collected in the container.

Abstract: A distillation system where a saline fluid (10) is pumped into a pressure vessel (14), through a counterflow heat exchanger (16) and heated to boiling. A salt free distillate (20) is separated from the saline fluid (10). The concentrate valve (24) and the distillate valve (26) restrict egress flow. The concentrate valve (24), the distillate valve (26) and the heater (18) are controlled by a computer control system (32) to attain and maintain a desired value of the Ewing Number. The Ewing Number is a dimensionless measure of performance defined as the heat of vaporization of the distillate (20) at standard atmospheric conditions times the distillate (20) mass flow divided by the system power input.

Abstract: A process is provided for separating high purity alkyl glycolate from a gaseous reaction mixture resulting from the catalyzed gas phase oxidation of alkyl glycolate. A hot solvent which is immiscible with water but selectively dissolves alkyl glycolate and alkyl glyoxylate is brought in contact with the gaseous reaction mixture, and water and alcohol vapors are removed from the hot solvent. The alkyl glyoxylate is removed from the solution by a first distillation and the alkyl glycolate and solvent are then separated in a second distillation.

Abstract: A dimensionally stable combustion synthesis product of a composition containing at least 20% by weight of a particulate combustible material; at least 15% by weight of a particulate filler material capable of providing desired mechanical and electrical properties; and up to 35% by weight of a particulate inorganic binder having a melting point lower than the combustion synthesis temperature. Electrodes suitable for electrochemical processing are a preferred product form, particularly electrodes for use in the electrowinning of aluminum from its oxide.

Abstract: A process for producing stable, high purity ferrate (VI) employing beta-ferric oxide (beta-Fe.sub.2 O.sub.3) and as the iron source. The process results in the efficient and effective productions of ferrate with high yields and small amounts of waste production.

Abstract: Nickel (or other transition metal) contaminated with about 5 ppm technetium is decontaminated by dissolving the nickel and the technetium into an aqueous acid solution while introducing a graphite or activated carbon powder into the acid to immediately adsorb the dissolving technetium. The technetium-contaminated powder is separated from the aqueous acid solution and the nickel is then electrowon from the solution. The depleted acid solution is then recycled back to the dissolution step.

Abstract: The present invention relates to an electropolishing tool for the removal of metal from a workpiece, said electropolishing tool comprising a container means for retaining an electrolytic solution, a cathode assembly in the shape of a pyramid the height of which is adjustable, a power supply means including a negative terminal and a positive terminal with said negative terminal being electrically connectable to said cathode assembly, a plate means for holding the workpiece and for forming an electrical connection to the workpiece, said plate means connected to the positive terminal of said power supply means, and an enclosure means placed over the workpiece leaving only the surface of the workpiece which is to be polished exposed to the electrolytic solution such that when the workpiece is secured to said plate means and said cathode assembly is connected to the negative terminal of said power supply means and is placed over the said enclosure means directly facing the workpiece enclosed therein, that portion

Abstract: An electrode used in electrochemical deionization comprises a current feeder disposed asymmetrically in an ion exchange material bonded into a coherant structure i.e. more of the ion exchange material adheres to one side of the current feeder than to the other side. The ion exchange material may be bonded by being provided in intimate admixture with a binder. Such an electrode offers manufacturing ease and the ability to be scaled up in multi-modular form.

Abstract: Apparatus and method for determining the concentration of NOx in a gas mixture. The gas mixture is supplied to two electrodes at which different NOx decomposition conditions are present. The electrodes may be of different materials or sizes or may be positioned in different gas enclosure environments. The NOx decomposes at different rates at the two electrodes and an emf is thus produced between the electrodes. The concentration of NOx in the gas mixture is determined from the measured emf.

Abstract: A method of metallizing a substrate by vacuum depositing a thin layer of chromium. The substrate is first cleaned (16) by exposing it to a plasma gas discharge. A thin layer of chromium metal is then sputtered under vacuum (17) onto the substrate. The substrate is then heated in an oxygen containing atmosphere (18) for a period of time and at a temperature sufficient to convert the chromium metal to chromium oxide. A second layer of chromium metal is then sputtered (20) onto the chromium oxide layer in order to form an adherent metal system to the substrate.

Abstract: A method and apparatus for the injection of a quantitatively defined volume of at least one fluid into a tube or capillary, in particular suitable for capillary electrophoresis systems by immersing at least one end of the tube or capillary in the fluid to be injected in the tube or capillary and generating an overpressure in a space above the surface of the fluid to be injected, wherein said overpressure is generated by means of a syringe device comprising a cylinder and a piston movable in a controlled manner in the cylinder, said cylinder being filled with a suitable gas and being connected via a pressure line to said space above the surface of the fluid to be injected.