Abstract: A method of forming and growing a single crystal of a semiconductor compound comprising a Group II-VI or Group III-V compound is disclosed. The method comprises placing a single crystal seed of the semiconductor compound adjacent to a first reactant comprising a Group II or Group III element. A protective blanket, resulting from at least a second reactant of a Group VI or Group V element, is formed over the seed within a temperature zone to protect the seed from dissolution by the first reactant. The reactants are combined to form a melt at a first temperature within the temperature zone and to grow a single crystal from the melt on the seed at a second temperature within the temperature zone.

Abstract: Disclosed is a method and apparatus for the automated growing of a floating zone refined, monocrystalline semiconductor rod. Two images of the molten/solid interface are separately positioned on two sensor arrays which, in addition to providing positioning feedback information, measure the diameter, the length of the molten zone and the "bag" or overhang angle of the molten semiconductor matter. The output of the sensor arrays are processed into signals which operate the zone refiner controls. There is thus provided an automated process for zone refining and monocrystalline rod growth of a semiconductor crystal from a seed crystal beginning with the tapering-out process, through the straight rod growth with a closely controlled diameter portion, to the end of the tapering-in process.

Abstract: Apparatus for producing monocrystals by potless zone melting, in which the monocrystal, setting out from a seed crystal, passes through a neck and a transitional zone into the main part of the monocrystal. A chamber is provided for the formation of a vacuum or a protective gas atmosphere plus a heating device for the production of the melting heat, driving means for the mechanical movements necessary for the crystal formation, a mounting for the seed crystal, and a supporting device which is applicable to the monocrystal beyond the neck, and a plurality of gripping bodies distributed about the circumference and applicable to the monocrystal radially on its substantially cylindrical surface the gripping bodies are disposed such that they first perform a radial approach to the monocrystal until a virtually force-free contact is made therewith, adapting themselves to the surface geometry and position of the monocrystal, whereupon the gripping force is increased and the gripping bodies are locked.

Abstract: A method of growing a monocrystalline bismuth rare earth iron garnet material from a melt in which a flux containing bismuth oxide and an alkali metal oxide is employed.

Abstract: Alkali metal halide crystals exhibiting substantially improved physical and optical transmission characteristics are grown from starting powders by a one step Reactive Atmospheric Processing (RAP) method.

Abstract: Large bulk single crystals of lead tin telluride are synthesized by first mixing desired amounts of lead, tin and tellurium with, if desired, bismuth and reacting the mixture at 950.degree. C to form a source material. The source material is then converted into a single crystal by recrystallization and digestion in a uniform 850.degree. C to 860.degree. C temperature zone in order to prevent transport of material and, hence, variations in composition. Thereafter, these crystals, which are doped with bismuth, or crystals made by Bridgman or Czochralski growth, are cut into wafers and isothermally annealed at 600.degree. C to 650.degree. C under a metal-rich vapor pressure obtained from metal-rich lead tin telluride powder. Lowering of temperature to about 200.degree. C and further annealing is capable of converting p-type crystals to n-type crystals. The result of annealing, whether p-type, n-type, or intrinsic, is a low carrier concentration, high mobility crystal.

Abstract: Method and apparatus for forming an elongated silicon crystalline body using a capillary action shaping technique. The means for growing and pulling the body from the capillary of the die includes a <110>{211}oriented seed crystal.

Abstract: A process is described for making optical circuits on LiTaO.sub.3 substrates. The process involves putting down an epitaxial layer of LiNbO.sub.3 on the LiTaO.sub.3 substrates. Growth is preferably carried out on certain planes of the LiTaO.sub.3. These optical circuits are unique in that they are smooth, uniform in thickness and have a refractive index significantly larger than that of the substrate. This is advantageous in optical circuitry, since the optical modes in the circuits are quite distinct and can be coupled separately using such light sources as lasers and light emitting diodes.

Abstract: A subterranean salt deposit is solution mined, and the resulting calcium- and sulfate-contaminated brine is treated, e.g., by soda ash, to precipitate insoluble calcium compounds. The resulting slurry is settled, and the effluent clear brine is evaporated in a series of solar ponds to produce high-grade sodium chloride.The brine becomes progressively more concentrated with respect to sodium sulfate as it moves through the solar ponds. The sulfate-enriched brine may be recycled to the solution mine, evaporated to form a sulfate-contaminated sodium chloride crystal crop, or it may be subjected to winter cooling to remove sulfate values as Glauber's salt, the residual brine being recycled to the solar ponds or the solution mine.

Abstract: A semiconductor body holder includes a rigid refractory base having a plurality of flexible refractory arms extending from one end thereof. Each arm includes a finger extending therefrom, the fingers in cooperation with the arms, serving to resiliently hold a body of semiconductor material during processing. The holder of the present invention is particularly useful in the practice of temperature gradient zone melting on the semiconductor body.

Abstract: The chlorinator for a swimming pool with a recirculation system includes a container to hold a column of chlorine concentrate solution, and a pool water supply conduit with a flow regulator connected to a return conduit of the recirculation system. Some of the pool water is caused to slowly flow into the container forming a gradually increasing column of pool water above the chlorine concentrate solution inside the container. A layer of separating material, having a specific gravity between that of pool water and that of the chlorine concentrate solution, rests on the bottom of the pool water in the container and floats on top of the column of the chlorine concentrate solution, and effectively prevents mixing of these two liquids. The gradually increasing column of pool water in the container then gradually forces the chlorine concentrate solution out of the container through another supply conduit to a height between the top and bottom of the container.

Abstract: Humidifying composition is introduced into a portable gas sterilizer in droplet form. The composition is packaged in an aerosol can and comprises water, preferably water and organic solvent. Automatic controls effect a predetermined relative humidity in the sterilizer before initiating sterilizing gas introduction.

Abstract: Powder flow in an apparatus for growing crystals according to the process of Verneuil, whereby powder falls downwardly into a flame impinging on and melting a surface of a seed crystal, is made uniform by isolating the powder supply container from oscillations in the air column beneath the container induced by vertical movements of a screening grid in the apparatus. Isolation is effected by a rotating sphere in a flow tube of the apparatus between the supply container and the oscillating screen, the sphere having close tolerances to the wall of the tube and vertical grooves in its periphery. The vertical grooves and the sphere surface also can meter the falling powder.

Abstract: The device comprises a vertically movable platform for supporting extraction flasks placed above compressed-air impellers. Withdrawal of the top liquid phase from each flask is performed by means of a vertical suction duct, the top end of which has its opening within a non-return chamber at a higher level than the opening of a tube which provides a communication with a pressure-reducing Venturi tube, ejector-nozzle and discharge pipe. The lower end of the suction tube is connected to a plurality of nozzles having their openings at the periphery of each extraction flask and extending in the same horizontal plane which can be set at a predetermined level.

Abstract: A crystallizable solute is crystallized from a solution containing the same by introducing a solution of said solute into a first stage evaporative-crystallization zone together with seed solute crystals. Within the first stage evaporative-crystallization zone the solution is concentrated to yield a saturated first stage concentrate containing crystals of said solute. The crystals of said solute are substantially larger than said seed crystals and are suspended in a solution more concentrated with respect to said solute than the solution supplied to said first evaporative-crystallizaton zone. A stream of said first concentrate is removed from said first evaporative-crystallizaton zone and transferred to a second evaporative-crystallization zone for further concentration or crystallization of solute and for the production of solute crystals of increased size.

Abstract: An apparatus for the production of pure alumina from alumina and silicate containing raw materials comprising means to feed said raw material into the top of an acid resistant leaching tower; means to continuously feed a leaching liquor containing hydrochloric acid into the bottom of said leaching tower, means to continuously flow said leaching liquor upward through said raw material to leach out the alumina as a solution of aluminum chloride, means to withdraw said solution enriched in aluminum chloride toward the top of said tower zone; means to withdraw said raw material solid residue from the bottom of said tower zone to convey said solid residue from said leaching tower into a separation zone at a level higher than the level of said leaching tower; and means to separate said solid residue from said carrier liquid in said separation zone.

Abstract: An automatic chlorinator for a swimming pool having a water circulating system. The chlorinator automatically draws a sample of pool water at regular intervals and compares the level of the residual chlorine in the sample with a predetermined desired level. If the residual chlorine in the sample is below the desired comparison level, the chlorinator automatically adds a measured amount of a chlorine saturated water solution to the pool.

Abstract: Large ultra-pure, prism-quality essentially single crystal boules and ingots of alkali metal chlorides and alkali metal bromides are grown by the methods of Kyropoulos and Stockbarger. Optically single crystals of these alkali metal halides are clear optical bodies free of haze throughout. A typical Kyropoulos grown boule of KBr of this invention is also absorption-free, and has cleavage or crystallographic planes which deviate from parallel by 1.degree. to 3.degree. per inch. By `absorption-free` is meant freedom of absorption at 7.2 microns (.mu.) due to nitrate, at 9.5-11 .mu. due to silicate, and at between 8 and 9 .mu. due to sulfate, which are the most difficult to control but as the term implies the bodies are also free of infrared absorption for impurities such as CO.sub.3.sup.-2, PO.sub.4.sup.-3, OH.sup.-, BO.sub.2.sup.-, SH.sup.-, CNO.sup.-, HCO.sub.3.sup.-, etc., which are easily avoided by use of good commercially available growth stock.

Abstract: Water soluble vinyl addition polymers and gums are rapidly dissolved in water by first dispersing these polymers or gums into a water-in-oil emulsion, then mixing the water-in-oil emulsion with water, preferably in the presence of a surfactant, and inverting the emulsion by passing a confined stream of the resultant mixture in a tortuous path to produce turbulence so that the water soluble addition polymer or gum is released into the water as a solution.

Abstract: A system for the conversion of liquid phases of non-metallic substances into solid phases, especially polymerizable or crystallizable substances, provides a reaction chamber in the form of an upstanding substantially tubular-shaped hollow body, at the upper end of which there is introduced the liquid phase and at the lower end of which there is continuously withdrawn the solid phase. The reaction chamber is enclosed at least at its upper region containing the liquid phase by a jacket of polygonal cross-section, wherein the wall sections of the chamber which in cross-section is polygonal are formed in each case by a run of an endless band which bears against the associated jacket section, each such band moving continuously downwardly by means of the aforesaid run and being substantially synchronously driven with the remaining bands.