Abstract: The present invention relates to a method of purifying gaseous nitrogen trifluoride from CF4 as impurity. The method comprises selective adsorption of nitrogen trifluoride by dehydrated erionite at a temperature of from ?30 to 30° C., displacement of carbon tetrafluoride by an inert gas, desorption and condensation of the purified nitrogen trifluoride. The purification yields 99.99% pure NF3 with CF4 content not over 10 ppm. The proposed method of NF3 sorption purification makes it possible to carry out the process at an ambient temperature and with long operating life of the sorbent. The method is practically feasible, economically expedient, and easy to implement under industrial conditions.

Abstract: The invention relates to a new process for preparing nitrogen trifluoride which finds extensive application in the technology of semiconductors, high energy lasers, and chemical vapor deposition. Nitrogen trifluoride is prepared by the fluorination of urea or its decomposition products with elemental fluorine in anhydrous hydrogen fluoride at a temperature of from −20° C. to 0° C. and the molar ratio of fluorine to the starting compounds of not over 3. The concentration of the starting compounds in anhydrous hydrogen fluoride is preferably 20-50% by weight. The proposed process is explosion-safe and gives a product with maximum content of nitrogen trifluoride and minimum concentration of admixtures, with the yield of up to 90%.

Abstract: The present invention relates to a process for producing fluorinated aliphatic compounds by pyrolysis of perfluorocarboxylic acids and their derivatives—halides and esters. The pyrolysis is carried out in the presence of a catalyst consisting of a carrier most preferably selected from the series comprising active carbon, magnesium oxide, calcium oxide, barium oxide, zinc oxide, aluminum oxide, nickel oxide, oxides of silicon promoted with alkali metal halides, selected from the series comprising fluorides, chlorides bromides, iodides of sodium, potassium, rubidium, cesium, at a temperature in the range of from about 100° C. to about 450° C.; with producing fluorinated aliphatic compounds selected from the series comprising perfluoroolefins, polyfluoroolefins and their derivatives; and also in the presence additionally of hydrogen fluoride with the formation of fluorinated aliphatic compounds selected from the series comprising polyfluoroalkanes and their derivatives.

Abstract: The engine comprises a chamber, fuel and oxidizer booster pumps, a turbopump unit, a gas generator, an electrically driven thrust regulator, and a fuel throttle. A programmable starting and ignition system is introduced, which includes a fuel tank, connected to the thrust regulator, and a first ampoule with starting fuel, an output of which through a starting/cut-off valve is connected to fuel injectors of the gas generator. The aforesaid tank is also connected through a second ampoule to the starting fuel and by a jet to autonomous ignition injectors located in the space of the combustion chamber of the engine. An inclined Archimedian screw pump with a gas turbine as an actuator and an oxidizing gas as a working medium is used as an oxidizer booster pump. The gas is discharged after its use in a turbine into an outlet manifold of the booster pump.

Abstract: A tank comprises a structural envelope made in a form of hemisphere with a tube connection having a ring groove in its surface. A tightening ring of the structural envelope. An elastic diaphragm made in a form of hemisphere integrated with a cylinder provided with an end projection that fits into the ring groove. A bottom is made in a form of a sphere part. A thin-walled ring with a shoulder is introduced that is mounted between the tightening ring and elastic diaphragm in the place of its end projection location. The tube flange is provided with an end projection. The tightening ring is equipped with a lateral flange providing a possibility for the thin-walled ring shoulder tightening by it to the ring projection of the tube flange. The external surface of the tightening ring and internal surface of the tube flange are made tapered in the direction from the ring groove to the hemisphere of the structural envelope above the ring groove.

Abstract: A combustion chamber for a liquid-propellant rocket engine includes an injector head jointed to a combustion chamber casing having an exhaust head on a nozzle output. The casing is made of a steel jacket and a bronze-steel internal fire wall, which are joined with each other and contain shells connected in series. The exhaust head with shells of the casing, jointed to the exhaust head, are brazed using a solder on the basis of nickel, chromium and manganese. Parts of the injector head and other members of the combustion chamber casing are brazed using a copper-silver solder. Shells of the fire wall are connected by an electron-beam welding, directing an electron beam into axial gaps left while brazing between shells of the jacket. The shells of the jacket are then sequentially connected by an automatic gas-shielded arc welding through corresponding ring spacers.

Abstract: The invention relates to the field of producing the means for protecting the alloys on the nickel base against the influence of corrosive media, and more particularly concerns the metal-ceramic coatings used for protecting the flow parts of the turbines of turbopump liquid-propellant rocket engines (LRE). The composition for producing the metal-ceramic coating consists of nickel and of oxides of barium, boron, aluminum, cerium and zirconium at the following percentage of components by mass: nickel--36-58, barium oxide--16-19, boron oxide--7-13, aluminum oxide--6-9, cerium oxide--14-19, zirconium oxide--1-2. The coating is produced of a slip, that is applied to the pieces by dipping, spraying or flooding. The slip layers are dried in the flow of hot air. The coating is fired in a furnace in the inert gas medium, argon for example, at a temperature of 1000-1100.degree. C. during 0.5-1 hour.

Abstract: A diamond-containing material having the following element content ratio in per cent by weight: carbon 75-90, hydrogen 0.6-1.5, nitrogen 1.0-4.5, oxygen the balance, the following phase content ratio in per cent by weight: roentgen amorphous diamond-like phase 10-30, diamond of cubic modification the balance, and having a porous structure. 10-20% of the surface of the material consists of methyl, nitryl and hydroxyl groups of two types, as well as functional oxycarbonic groups of the general formula O.dbd.R where R represents .dbd.COH, .dbd.COOH, .dbd.CO, .dbd.C.sub.6 H.sub.4 O or any of their combinations, and 1-2% of the surface constits of carbon atoms with non-compensated links. A method for obtaining said material consists in detonation of a carbon-containing explosive substance with negative oxygen balance, or a mixture of explosive substances, in a closed volume in the atmosphere of gases inert to carbon, with an oxygen content of 0.1-6.

Abstract: A new chemical compound, ketopantoyl aminobutyrate of formula I: ##STR1## and its salts. The compound is obtained by interaction of ketopantolactone and a salt of .gamma.-aminobutyric acid.It was shown that the new compound exhibits sedative, anti-amnesic and antihypoxic properties.

Abstract: The invention concerns a tobacco smoking article comprising a tobacco rod and a filter unit containing both organic and inorganic fibers wherein the inorganic fibers are basalt fibers with diameter of no more than 0.6 .mu.m.

Abstract: There is proposed a water treatment method by causing the water to be pured to flow through a first and a second compartments arranged in succession in an electrolysis cell divided by a permeable membrane into said first and second compartments. Each of the compartments accomodates an electrode, one of them being an anode, and the other--a cathode. Direct electric current is then passed through the water between the anode and the cathode, the current value being determined from the following equation:I=K.times.(C).sup.1/4 .times.Q,whereinI is the current amperage (A),C is the feed water mineralization equal to 0.1-1.5 g/l,Q is the water flow rate (1/hour), ##EQU1## the I/Q ratio being comprised within from about 110 to about 220 Coulomb/liter. The water is caused to flow successively from the anode compartment towards the cathode compartment. Once the water is discharged from the cathode compartment, it is subjected to filtering by passing the water through a bed of a porous carbonaceous material.

Abstract: A bearing assembly is designed for high-speed heavy-duty vertical shafts and has a casing (1), antifriction bearings (3) with outer (5) and inner (4) races, and a load redistribution system (A). The load redistribution system (A) has elastic members (7) provided between the outer races (3), rigid spacer sleeves (6) provided between the inner races (4), and coupling members (8) engaging one another and, via separating members (9), the elastic members (7).

Abstract: The composition is formulated as follows, in percent by weight:synthetic corundum material: 76.5 to 90.0kaolinite: 2.1 to 5.7feldspar: 2.8 to 7.6adhesive and moistening ingredient: 3.0 to 4.5calcium borosilicate frit: 2.1 to 5.7Calcium borosilicate frit compositon, in percent by weight, is as follows:silicon oxide: 22.0 to 38.0aluminium oxide: 14.5 to 15.5boron oxide: 25.0 to 35.0calcium oxide: 12.5 to 17.5sodium oxide: 4.0 to 7.5potassium oxide: 2.0 to 3.5The boron oxide-to-calcium oxide ratio is within 1.5 to 2.5.

Abstract: A flow amplifier in the hydraulic steering system of a transport vehicle comprises a three-position hydraulically operated hydraulic directional control valve having a single sliding spool valve and internal hydraulic pilot lines connected, when in the crossover position, to external portholes made in a sleeve of the three-position hydraulically operated hydraulic directional control valve provided with plungers spring-loaded on their outside end faces. The flow amplifier incorporates also a pair of intensifying chokes, a air of pilot chokes, and a pair of regulating chokes made in the sliding spool valve with a possibility of varying their restriction areas along the direction of travel of the sliding spool valve.

Abstract: The work-performing member for a farm machine has a cutting edge made of a high-carbon steel containing graphite in structurally free state in an amount of 0.5 to 1.32 percent of the total mass of the material.

Abstract: An intrauterine contraceptive device, comprising a strip with rounded-off ends, a rod connected to the strip to form a T-shaped element therewith, a fixing element for retaining the entire device in the uterine cavity, made as an elastic loop, and a coil fitted over the rod, the elastic loop of the fixing element having an arc-shaped base and two elastic arms connected to the base and secured to the strip at the base of the rod, which elastic loop is coplanar with the rod and strip and encompasses the rod.

Abstract: An intrauterine device includes a transversal member, a rod connected to the transverse member to form a T-shaped element therewith, a coil mounted on the rod, and a thread for dynamic monitoring of the IUD in the uterine cavity, the thread being passed over the transversal member at the place where the transversal member is connected to the rod and being interposed between the rod and the coil lengthwise the former.

Abstract: A process for producing sulphur from calcium sulphate wherein a charge is granulated from powder-like calcium sulphate and a carbonaceous component at a mass ratio of carbon of the carbonaceous component to calcium sulphate of 0.08-0.09:1 respectively; mixing of the resulting charge granules with a lump-like carbonaceous material at a mass ratio of carbon of the carbonaceous material to the charge granules (as calculated for dry solids) equal to 1:3-10 respectively; heating the mixture of the charge granules with the lump-like carbonaceous material in a vertical calcination furnace while continuously moving said mixture in a downward current simultaneously with counter-currently supplying an oxygen-containing gas; the maximum heating temperature being maintained within the range of from 1,100.degree. to 1,200.degree. C. and the temperature of the upper bed of said mixture in the furnace being maintained equal to 500.degree.-600.degree. C.

Abstract: A method of measuring the direction of mechanical vibrations, in which a plurality of points are marked on the surface of a vibrating object along the arc of a circle of a given radius at a constant pitch selected from a range of 1.2 to 1.8 of the amplitude of mechanical vibrations, forming a circular scale and while moving together with the vibrating object making up, depending on the shape of a trajectory of mechanical vibrations, stroboscopically still equal segments of a straight line or patterns. A group of straight line adjacent segments disposed at a minimum distance in a radial direction or patterns having a maximum overlapping and a radially arranged axis of symmetry is visually defined. An ordinal number is determined of one or two straight line segments or of one or two patterns through which the axis of symmetry passes, and the direction of mechanical vibrations is measured on the circular scale by an angle corresponding to this ordinal number.

Abstract: A method of melting steel in an oxygen converter from solid metal iron-bearing materials includes the steps of loading these materials and their subsequent heating up to their melting through burning hydrocarbon and solid carbon-containing fuels in an oxygen-containing gas. Then, when the temperature of the melt is 1525.degree.-1580.degree. C. the oxidizing slag is removed from its surface and thereafter a solid iron is loaded into the bath in an amount of 2-5% of the original quantity of the solid metal iron-bearing materials.