Abstract:
Process of rapidly cooling containers located in a chamber having an at least partially vaporous atmosphere, comprises the steps of introducing into said chamber a cooling liquid which does not come into contact with the containers and a compressed gas which maintains the pressure within the chamber substantially constant while the vapor condenses, and then spraying into the chamber, while still controlling the pressure therewithin, a cooling liquid which does come into contact with the containers and the temperature of which decreases progressively. Apparatus for carrying out said process.
Abstract:
The process of forming polyolefin fibers comprising polymerizing an olefin in a solvent or dissolving a high molecular weight polyolefin in the solvent at a temperature above the melt dissolution temperature of the polyolefin to be formed, and cooling the reaction mass to a temperature below the melt dissolution temperature to form a fibrous gel containing polyolefin microfibrils, macrofibrils and fibers.
Abstract:
Apparatus for growing epitaxial layers of semiconductor material on substrate wafers at a relatively high production rate comprises a reactor furnace and a loading device cooperatively associated with it. An elevator is disposed to raise, and to lower, a holder for the wafers through an opening in the bottom of the heating chamber of the furnace. The loading device comprises an arm disposed for rotation on a carriage that is slidable towards and away from the elevator. The holder is adapted to be disposed on either end of the rotatable arm for delivery to, and for removal from, the furnace. When the loading device is disposed for movement between two furnaces, three wafer holders can be used for processing wafers at a high rate of production.
Abstract:
A reinforced-conrete vessel adapted to withstand pressure, e.g. for a pressurized-fluid nuclear reactor, has an inner lining of corrosion-resistant (stainless) steel having vertically or horizontally-running corrugations, the crests of which are supported by steel profiles.
Abstract:
A pressure vessel unit for use in doubling back a continuously advancing cable, tube, strand or the like, during a treating operation. The unit includes a vessel, which defines a generally horizontally disposed pressure chamber housing a freely rotatably or driven sheave to which access is afforded by a quick opening door; the vessel having cable run inlet and outlet fittings arranged tangentially of the peripheral guide surface of the sheave and inlet and outlet connections for admitting and/or bleeding cable treating fluid from the chamber. The arrangement provides for the establishing of a liquid-gas interface within the chamber, when the cable is to be subject to separate liquid and gas treating operations. The vessel is supported for movement in a direction axially of the cable runs to accommodate for thermal induced expansions and contractions of cable run bounding conduits.
Abstract:
A process for mass polymerization in an autoclave having rotatable ribbon agitators (see Group II) is described with reference to an example in which 210kg. vinyl chloride were introduced into an autoclave of 500 litres capacity and 0,06 kg. or 0,03% of azodiisobutyronitrile added as catalyst. 10 kg. of monomer were removed in degassing to expel air and the agitator rotates at 70 r.p.m. The pressure mounted to and was maintained at 9,05 kg./cm2, and the temperature was maintained at 54,5 DEG C., by cooling and heating as required, until after 16 hours the pressure fell to 8,5 kg./cm2. The pressure was then released, the apparatus swept by nitrogen and the product discharged, being a finely pulverized polymer of vinyl chloride representing a yield of 73,21% of the monomer, having an apparent density of 0,480 and more than 88% passing through a 250 micron mesh sieve. The resin had a polymerization coefficient K of 63,1, a low polymer rate of 4,8% by weight and a stability to heat (200 DEG C.) of 19 minutes. The physical properties of the product may be controlled by selecting the rate of rotation of the agitators. The apparatus may also be used for polymerization in suspension or emulsion or applied to other monomers, e.g. vinyl fluoride, vinylidene chloride, acrylic nitriles, ethylene and propylene.