Abstract: An engine air cleaner comprising a cylindrical housing containing an annu perforate cleaning medium and a set of pre-cleaning baffles in the housing space surrounding the cleaning medium. The baffles maintain the dust-laden gas in a swirling condition, thereby centrifugally forcing heavy dust particles away from the cleaning medium surface. A scavenger fan removes heavy dust particles from the housing before such particles can contact the cleaning medium.

Abstract: Reheating the cooled wafer product of the known method of forming thermal oxide surface passivation layers on GaAs crystal wafers, i.e. heating the wafer in contact with thermally vaporized As.sub.2 O.sub.3 in a substantially oxygen free closed vessel at a reaction temperature in excess of 450 degrees, from a temperature lower than the reaction temperature to a temperature higher than the reaction temperature and in the presence of free oxygen increases the compositional, physical and electrical uniformity of the surface layer.

Abstract: Liquid atomizer having a vibration generator for generating vibrations, an atomizer element receiving the vibrations, and a container with liquid to be atomized. Liquid is transported solely and directly from the container to the atomizer element by a wick of elastically resilient material in contact with liquid in the container and at a point remote from the liquid in the container, mechanically coupled to the atomizer element by disposing the wick against the atomizer element. A tube may surround the wick until almost to the coupling point.

Abstract: Evaporation air humidifier having a water supply container with a filter support plate carrying an evaporation filter, and having a removable auxiliary plate whereon electrical components are assembled including a motor and a pump driven thereby and extending into the water supply container, as well as a fan blade disposed on an upper side of the motor, and an installation housing, and further having a connecting hose interconnecting the pump and the evaporation filter and a dome with air inlet and outlet openings including a guide member carried by the auxiliary plate at the underside thereof, a guide secured to the water supply container and engageable with the guide member, a first coupling member for the connecting hose carried by the auxiliary plate, a second coupling member held by the filter support plate, the first coupling member being automatically couplable with the second coupling member when the guide member and the guide are mutually engaged.

Abstract: Single crystals are conveniently produced by directional solidification of a liquid body under a pressurized atmosphere and, preferably, under a liquid encapsulating layer to minimize loss due to volatilization. Such fabrication entails a concern with internal stress in a grown crystal in the interest, e.g., of minimization of breakage of wafers cut from a crystal. According to the invention, minimization of stress is accomplished by means of a post-growth annealing step during which pressure is reduced substantially and, in particular, preferably to a pressure which does not exceed 50 percent of a pressure at which a constituent of the liquid body volatilizes.The method may be applied for producing single crystals of semiconductor materials as may be used as device substrates. In particular, the method is beneficial, e.g., for producing high-quality doped or undoped InP, GaP, and GaAs single crystals.

Abstract: In an apparatus for cleaning hot gases a filter housing has an inlet for unfiltered gas and an outlet for filtered gas. A plurality of filtered inserts are placed within the housing in a manner capable of filtering undesirable components from the gas feed stream. Each filter insert is made of a fibrous filter material. Silicic-acid glass fibers have a silicic acid content of at least 90%. Coated upon the fibers and absorbed into their pores is a metal oxide of aluminum, titanium, zirconium, cromium, nickle or cobalt. A honeycombed cage filled with high temperature resistant perlite is located within the housing between the gas inlet and the fiber inserts. The cage has an inlet and outlet external to the housing for replacing the perlite. A combustion chamber mounted in the housing has a discharge nozzle located so that the nozzle is directed at the filter inserts. Combusting materials in the chamber causes an explosive backflow of gases through the filter inserts.

Abstract: A manway cover is formed using two like door panels made of lightweight, corrosion-resistant material which are hand operable from either side of the manway and can be installed without tools.

Abstract: A drum type screening machine has a centrifuging rotor within it. A perforated retaining element is carried by the shaft between a feed inlet and an entry region of the drum. Use of the retaining element prolongs the screen life so much that tension adjustment become necessary. Provision is made for this to be done from outside of the machine. The screening drum has a pair of rings which support the screening cloth and which are held apart at an adjustable distance by tensioning bars. One ring is supported within an end member of the machine housing and the other on support means within the housing. Each bar is externally threaded, e.g. by way of an extension sleeve that is axially fast with the bar. The sleeve is engaged by an internally threaded nut which is axially fast with the end member of the machine. The sleeve extends through that nut and through the end member to the outside of the machine.

Abstract: An evaporative dispenser is disclosed for emitting a vaporized material into the ambient. A battery powered, motor driven fan forces air through the dispenser housing and across a material reservoir to evaporate and entrain material therein prior to being discharged from the housing. A supply container is supported directly on a reservoir lid and comprises structure which cooperates with the housing to direct the air flow across the reservoir. The supply container also comprises a battery nesting recess which affords compact packaging of the components within the housing. A transparent viewing window is provided for easy viewing of the level of material in the reservoir.

Abstract: Exchanger element for the bottoms of an exchanger column comprising a cylinder having grid openings in the side wall, a fixed cover plate at the top of the cylinder for deflecting gas and a movable apertured valve plate inside the cylinder normally covering the opening in the exchanger bottoms.

Abstract: A dust aspirating arrangement, particularly for underground applications, has a suction element arranged for aspirating air which contains dust generated during operation of an underground machine, an agglomerating section communicating with the suction element and arranged for receiving the dust-containing air aspirated by the latter in which agglomerating section a mixture of a moisture and the dust-containing air is produced, a separating element communicating with the agglomerating section and operative for separating the mixture into its constituent dust-containing moisture and air and provided with a flexible conduit for removing the separated dust-containing moisture, and a removing element for removing the separated air from the separating element and located downstream of the flexible conduit.

Abstract: A seed and method for epitaxial solidification of materials, a preferred seed having at least a portion with a melting point 20.degree.-45.degree. C. depressed from that of the alloy being solidified into an article. Boron and silicon are preferably added to nickel superalloys seeds when directionally solidified columnar grain and single crystal articles are formed. Improved seeds also have surface compositions which promote the dissolution of surface contamination films that interfere with epitaxy.

Abstract: A method and associated apparatus are disclosed for the continuous formation of single crystal silicon ribbons. A seed crystal is placed on the surface of a pool of molten silicon and pulled at a slight angle above the horizontal over the edge of a meniscus attachment member at a rate commensurate with the rate of growth of the ribbon. The formation of the ribbon is controlled in part by a submerged stabilizer disposed under the molten silicon below the advancing edge of the ribbon at the surface of the silicon. A thermal impedance is provided below the surface of the molten silicon to provide stability in the formation of the ribbon and to provide the proper temperature gradients conducive to the efficient formation of the ribbon from the molten material.

Abstract: Gas diffusion elements, formed of a body of solid particles which have been shaped, pressed and rendered coherent by bonding or sintering in a compacted form having pores, are disclosed. Said elements include a peripheral, annular zone of relatively small proportions having lesser permeability, greater density or lesser height than at least a portion of the remainder of the element. In accordance with the invention, a boundary zone is provided adjacent to and inwardly of the peripheral zone, in which boundary zone there is a progressive increase, continuous or step-wise, in the apparent volumetric compression ratio of the element, in the direction of the pheripheral zone, or towards a vertical surface which is near the periphery of the element. Such element may provide improved gas, e.g. oxygen transfer efficiency and therefore holds promise of improving the efficiency and economics of gas transfer processes, such as for instance treatment of sewage or other waste water with air, oxygen and/or ozone.

Abstract: The low temperature red form of mercuric iodide is grown by a chemical transport method which introduces organic monomers or polymers during the crystal growth process. Resulting crystals are in the form of platelets which are more directly useful in radiation detector device applications. Platelets near one centimeter in width and 200 .mu.m in thickness have been grown in periods of a few days using only 99.9% (unpurified) starting material.

Abstract: The present invention utilizes a closed-type vessel comprising a filtering chamber, at least one perforated filter cylinder a portion of which is positioned within the filtering chamber, said filter cylinder being rotatable at any desired speed and having a filtering surface covered with a filter cloth, and a squeezing roll and sealing roll which engage with said filter cylinder through the filter cloth at all times to define a sealing and operating wall. Any sewage to be treated is supplied under pressure to the filtering chamber and filtered through the filter cloth at the filtering surface of the filter cylinder. Filter cake deposited on the filter cloth is continuously transferred to the outer periphery of the squeeze roll and then separated therefrom outside the filtering chamber by any suitable means such as a scraper.

Abstract: An apparatus for separating almost all fine particles, including particles less than 10 microns in diameter, from a gas stream, which requires the input of only a small amount of water and which discharges a correspondingly small amount of particle-water slurry. The apparatus includes a vertical cylindrical chamber having a relatively wide upstream portion that gradually narrows in a transition portion into an elongated throat portion. A central core member extends axially along the throat portion and forms an elongated annular passage. A high velocity gas stream containing fine particles is generally tangentially introduced into the wide upstream portion of the conduit to provide a circulatory flow. Water is introduced through a plurality of parts in the transition portion downstream therefrom, to provide a thin layer of water along the outer walls of the throat.

Abstract: A process for forming a relatively defect free layer of silicon on an insulating substrate wherein as soon as growth islands are formed on the substrate, to a point just prior to the complete coverage of the substrate with silicon, the formation of the layer is temporarily terminated. The growth islands are maintained at a given temperature for a predetermined period, to allow any defects, which may have started during the initial formation of the growth island, to be self-cured or to annihilate themselves. Thereafter, the growth of silicon is continued until the desired layer thickness is achieved.

Abstract: A vapor-liquid contacting tray wherein a perforated portion of the tray member forms an active surface area for vapor-liquid contact in the interior of the tray member. The active surface area portion of the tray member is circumscribed by an imperforate peripheral portion of the tray member with a width of from 0.05 to 0.35 times the radius of the tray. The disclosed tray provides upwardly directed laminar jetting of liquid over the tray perforation openings for high selectivity vapor-liquid contacting and has particular utility in the absorption of hydrogen sulfide from a gas mixture containing hydrogen sulfide and carbon dioxide.

Abstract: Dual baffle aerators substantially prevent back-mixing of freshly aerated liquor into aerator intakes and provide directional propulsion. By connecting two or more such devices to form a barrier across the channel of an oxidation ditch, homogeneous aeration is provided to the mixed liquor.Barriered pump/aerator assemblies utilizing directional mix jet aerators (eddy jet) can also be combined with dual-baffle aerators.An adjustably apertured barriered pump assembly is opened sufficiently to conserve momentum in the translationally flowing liquor while preventing back-mixing of aerated liquor.Processes for providing point-source or multi-source aeration, by using two or more barriered pump assemblies, can be provided at one barrier and the advantages of point-source homogeneous aeration can be provided at another barrier, at least one barrier being adjustably apertured.