摘要:
Metal and/or partial metal dentures having a surface modified by a pulsed electron beam system. The system includes an explosive emission cathode, an accelerating gap formed by the cathode and plasma anode, and an electron collector where the metal and/or partial metal dentures are fixed, and placed into a magnetic field. The surface of the modified metal and/or partial metal denture has high reflectance like a mirror polished surface and high corrosion resistance.
摘要:
Disclosed is a method of drying timbers loaded in a drying chamber, which comprises the steps of heating the drying chamber by a heating system up to a temperature of 80 to 100° C., subjecting the timbers to vacuum blowing by connecting the inside of the drying chamber with a vacuum chamber (receiver) evacuated by a rotary pump until the inside pressure of the drying chamber drops to 1 to 10 mmHg, disconnecting the inside of the drying chamber from the vacuum chamber, connecting the drying chamber with the atmosphere. When the inside of the drying chamber is connected with the vacuum chamber, the moisture content of the timbers is sharply reduced, so that their temperature sharply drops. Thereafter, when it is disconnected from the vacuum chamber, and connected with the atmosphere, the inside temperature of the drying chamber is again increased. Meanwhile, the heating system is worked during the whole process. The above steps constitute one cycle that is sequentially repeated until the moisture content of the timbers drops to a desired level. Preferably, the connection between the drying chamber with the vacuum chamber is made in 0.1 to 0.5 seconds. Pressure release is made in the vacuum for 0.5 to 5.0 seconds until reaching equilibrium moisture. The blow-down in the vacuum is carried out by a heat carrier with a temperature of 80 to 150° C. until reaching the volume average material temperature of 80 to 90° C. with the subsequent pressure release in the drying chamber lower than the equilibrium, thus providing high-speed vacuum blowing.
摘要:
A turbomolecular high-vacuum pump has a substantially vertically extending cylindrical casing provided with inlet and outlet pipes for gas being evacuated. The casing accommodates, in the top part thereof, a stator having vanes disposed between the rotor vanes so as to define passages for gas being evacuated. The rotor is connected to a high-speed hollow shaft extending substantially vertically. The shaft is journalled in bearings and connected to the rotor by means of a high-frequency electric drive motor. The pump incorporates means for lubricating the bearings. The stator of the high-frequency drive motor of the pump is electrically coupled to the stator of a generator of a machine-type frequency converter which has an induction drive motor. Another, low-speed shaft is journalled in the bearings in the bottom part of the pump casing coaxially with the high-speed shaft, one shaft embracing the other. The induction motor rotor and the rotor of the generator of the machine-type frequency converter are mounted on the low-speed shaft, the stators of both devices being fixed within the pump casing. Means for lubricating the bearings of both shafts is disposed at the lower end of the low-speed shaft.
摘要:
An apparatus is designed for hard-facing internal combustion engines valves by the melting and fusion in high-frequency current field of heat-resistant rings of hard alloy upon the seating surface of the valves. The apparatus comprises an actuator means mounting gripping jaws and a support which is adapted to receive the ring and to feed it onto the valve stem at the moment the valve being gripped by the jaws. The actuator associates with a manipulator adapted to provide for turning movement thereof in two mutually perpendicular planes, thereby conveying the valve with the ring positioned on its seating surface from the receiving area fusion or welding zone, the valve stem being upwardly directed at the same time. The apparatus features high efficiency owing to combining the steps of putting the alloy ring on the valve and conveying the latter to the welding or fusion zone.
摘要:
An aircraft steering surface actuator has an electric motor, a reduction gear and a step-by-step control mechanism in the form of a cam-operated breaker in the electric motor power supply circuit. The breaker automatically deenergizes the electric motor when the steering surface is turned through one step, thus preventing the steering surface from inadvertent movement to the extreme position in case of trouble in the system.
摘要:
A method for the production of films having the desired geometrical form (configuration) comprising depositing an electromagnetic radiation-sensitive system, which consists of a metal layer and an inorganic compound layer capable of reacting with said metal layer and forming interaction products under the effect of electromagnetic radiation, onto a film made from a material which does not react, on being irradiated, with the layer of said system that adjoins said film; subjecting said system to selective irradiation in conformity to the desired configuration, followed by carrying out the selective etching of the irradiated system so as to obtain the requisite configuration, and thereafter using said etched system as a mask for etching selectively said film in order to impart thereto the sought-for geometrical form.
摘要:
A device wherein an explosion chamber accommodates a part shaped as a body of revolution forming with the internal side surface of the explosion chamber an annular space filled with a gas mixture, the magnitude of said space in the chamber cross-section being varied in the direction of propagation of the detonation wave front so as to transfer detonation conditions of the gas mixture burning in the explosion chamber; the arrangement of the part within the explosion chamber offers a reduction in the consumption of the gas mixture, as compared with the known devices for explosion gas-forming, and in metal requirements for the manufacture of the explosion chamber.
摘要:
A process for producing amethyst crystals involving growing of colorless quartz crystals by a hydrothermal method of a temperature drop in a high-pressure autoclave on crystalline quartz seed plates oriented parallel to the crystallographic planes of the major {1011} and minor {1101} rhombohedrons using crystalline quartz as a charge. Said growing is effected from aqueous solutions of potassium carbonate or potassium hydroxide having a concentration ranging from 4 to 7 wt.% and containing iron introduced into the autoclave in the form of metallic iron or in the form of its oxydic or hydroxydic compounds in an amount ranging from 5 to 30 g/l of the solution. The growing process is effected at a crystallization temperature within the range of from 300.degree. to 500.degree. C. under a pressure ranging from 200 to 1,700 kg/cm.sup.2 and a crystal growth rate of from 0.05 to 0.5 mm/day. It is advisable to introduce into the autoclave, prior to the crystal growing, lithium nitrite or lithium nitrate or manganese nitrate in an amount ranging from 1 to 10 g/l of the solution. The thus-grown colorless quartz crystals are exposed to an ionizing irridation. The process for growing crystals according to the present invention is well-reproducible, since it is performed at specfied physico-chemical parameters. The process of the present invention enables the production of amethyst crystals with a high color purity and a high transparency (i.e., with no cracks).
摘要:
A photocolorimetric gas analyzer based on a sensitive element, comprising a radiation source whose electromagnetic radiation is received by the sensitive element which is made in the form of a gas-impermeable tablet containing a selective reagent and an inert filler, which changes the optical properties of its surface layer as a result of the reaction of one of the components of the gas mixture being analyzed and the reagent; a radiation detector to receive the radiation reflected by the surface layer; and means for mechanically removing the latter.
摘要:
A method of producing tubes from sheet metal blanks on a mill comprising the steps of: feeding said blanks in a sequence; measuring the length of each sheet metal blank; leaving the pairs composed of the blanks approximate in length in the sequence by removing from the sequence the unpaired blanks, ensuring pairing of the blanks removed from the sequence but meeting the pre-set limits as to their difference in length. Following that the known treatment of the edges being welded is performed, alternate forming of each sheet metal blank assembly in pairs and welding of said blanks into tubes with subsequent trimming of the tube ends.