Abstract: A fiber optic coupler is formed by providing a glass tube having a longitudinal aperture extending therethrough. Glass optical fibers, each having a core, cladding and coatng are disposed within the longitudinal aperture, the fibers extending beyond each end thereof. The coating is removed from that portion of the fibers in the midregion of the tube but remains on that portion of the fibers extending into the ends of the apertures. The aperture is formed by a plurality of flattened walls, the dimensions and orientations of which are such that the cross-section of the aperture in the central region of the tube is symmetrical with respect to a plane passing through the longitudinal axis of the tube. At any cross-section of the aperture that is adjacent the coated regions of the fibers, each fiber coating contacts two walls of the aperture.

Abstract: In the conversion of light olefins to heavier hydrocarbons, an improved recovery technique is provided for selectively removing unreacted light olefins from a catalytic reactor effluent. This system is useful in converting ethene-rich feedstocks to gasoline and/or distillate products, particularly in oligomerization processes employing shape selective siliceous catalysts such as ZSM-5 type zeolites. By recycling gasoline-range hydrocarbons as a sorbent liquid, unreacted C.sub.2.sup.+ components may be absorbed from reactor effluent vapor and returned for further contact with the catalyst.

Abstract: The device pursuant to the invention comprises means for agitation composed of at least one horizontal agitator formed from a series of essentially vertical loops extending over the entire width of the bath near the collar between the refining zone and the homogenization zone, with the horizontal agitator being moved by means that produce an elliptical motion in the horizontal plane.

Abstract: A single-step process is disclosed for hermetically sealing a glass to a metal having similar coefficients of thermal expansion without carrying out the conventional pretreatment steps of decarburization and oxidization by heating to at least the melting point of the glass in an atmosphere containing from about 0.5 to 2.5 volume percent of water vapor, 0 to about 5 volume percent of hydrogen gas and the balance an inert gas, such as nitrogen.

Abstract: The present invention provides an improvement in the appearance of a cathode-ray tube including a rectangular faceplate with an exterior surface having curvature along both the minor and major axes. The faceplate also includes a cathodoluminescent screen on an interior surface thereof. At least in the center portion of the faceplate, the curvature along the minor axis is at least 10 percent greater than the curvature along the major axis. Points on the exterior surface near the ends of the major axis, at the edges of the screen, lie in a first plane which is perpendicular to the central longitudinal axis of the tube; points on the exterior surface near the ends of the minor axis, at the edges of the screen, lie in a second plane which is spaced from and parallel to the first plane; and points on the exterior surface near the ends of the diagonals of the rectangular faceplate, at the edges of the screen, lie in a third plane which is spaced from and parallel to the first plane.

Abstract: A process for forming a channel waveguide in which the channel geometry and the channel index of refraction vary oppositely along the channel length to keep the modal characteristic of the channel uniform uses non-uniform heating of a channel waveguide to cause non-uniform diffusion of the channel dopant. In one embodiment, the channel is passed under a laser at a non-uniform rate to expose the channel to different numbers of laser pulses.

Abstract: A process for the recovery of minerals from an ore or concentrate containing the same wherein the minerals are recovered in a froth from an aqueous pulp containing the ore or concentrate and wherein one or more mineral flotation agents are employed in the aqueous pulp to control the type of mineral in the froth is provided. The mineral flotation agent or agents employed in the process comprise sulfenyl dithiocarbamates characterized by the formula: ##STR1## wherein R.sub.1 and R.sub.2 are selected from the group consisting of hydrogen and hydrocarbyl groups with not more than one of R.sub.1 and R.sub.2 being hydrogen, n is 1 or 2, and R.sub.3 is a hydrocarbyl group.

Abstract: Pool or spa water can be monitored for dimethyl hydantoin content, as a residue of disinfection with halogenated hydantoin, by determining the quantity of base required to adjust the pH to 9.3. The pH may be judged by a suitable indicator for example thymol phthalein or thymol blue. The method can be applied either titrimetrically, or by comparison colorimetrically with standard solutions and may be modified for use in relation to other halogenated hydantoins. The method may be applied to the testing of pools for compliance with an advisory dimethyl hydantoin content limit and may be embodied in a kit for easy poolside use.

Abstract: Air filtration systems and methods which intentionally use collected dust to enhance air filtration performance, use air flow rate control to optimally maintain electro-mechanical efficiency and media permeability, use high velocity discharge to "throw"clean air to preferable workplace areas, and use a cylindrical drum design for pleasing appearance and practical features. The systems and methods are particularly applicable as modular filtration units to textile processing environments, but are suitable for more general applications as well.

Abstract: A new depressant composition is provided for the enhanced separation into separate value metal concentrates of copper, nickel, zinc, lead present in polymetallic and massive sulphide ores.The depressant is added in an aqueous solution prepared by dissolving first a mixture of quebracho and dextrin, or quebracho and guar gum. To the solution of modified quebracho a water soluble salt of lignin sulphonate is added. The aqueous polymer of modified quebracho lighin sulphonate is further mixed with one or more of the following inorganic reagents: water soluble cyanide, metal sulphates and water soluble sulphites. The resulting depressant is added together with conventional flotation reagents in conventional mineral separation stages as required.

Abstract: The circuit board plasma etching apparatus includes a preheating chamber, a plasma reaction chamber and a cooling chamber for etching circuit boards with plasma in a quasi continuous operation. The plasma reaction chamber is sealed by a gas-tight preheating sealing slide adjacent the preheating chamber and by a gas-tight cooling sealing slide adjacent the cooling chamber. A preheating door selectively closes the preheating entry end and a cooling door selectively closes the cooling chamber exit end. Boards to be etched are placed in printed circuit board cages supported by a guide rail within the chambers. The guide rail is separable into a preheating segment, a reaction chamber segment and a cooling segment contained within the respective chambers. A preheating chamber bellows allows axial movement of the preheating door, as does a cooling chamber bellows for the cooling chamber door. Axial displacement of the doors allows selective segmentation of the guide rail.

Abstract: A method for producing a glass preform for an optical fiber comprising a core and a cladding containing fluorine is fisclosed. The method comprises forming a porous glass layer of substantially pure quartz on an outer surface of a fused glass rod consisting of a central portion of substantially pure quartz and a peripheral portion of quartz glass containing fluorine, and heating a composite of the fused glass rod and the porous glass layer in an atmosphere containing fluorine to add fluorine to the porous glass layer and to make it transparent, by which contamination of glass with hydroxyl groups can be prevented and light transmission characteristics of an optical fiber fabricated from the glass preform are improved.

Abstract: An elastically deformable press cover of a press for dewatering web material, in particular of a dewatering press for paper making machines, or the like. The press cover surrounds a support and is an endless belt. At its outside, which faces toward the web, the press cover has ridges which lie in preferably equidistant diametral planes or run round the cover in the form of a helical line. Between the ridges there remain grooves which are open to the outside. As seen in cross-section, the top lands of the ridges are concave.

Abstract: The present invention relates to an improved process for beneficiating an ore containing sulfide materials with selective rejection of pyrite, pyrrhotite and other metals and gangue. In particular, the process is useful for beneficiating ores and recovering copper from said ores. In one embodiment the process comprises the steps of(A) grinding the ore to an appropriate size range;(B) preparing a slurry comprising(B-1) said ground ore;(B-2) at least one collector which is a water-dispersible or soluble dihydrocarbyldithiodiphosphoric acid or salt having the formula ##STR1## wherein R.sup.1 and R.sup.2 are different hydrocarbyl groups containing up to about 12 carbon atoms, n is an integer equal to the valence of X and X.sup.n+ is a dissociating cation; and(B-3) water;(C) conditioning the slurry with SO.sub.2 under aeration at a pH of about 5.5 to about 7.

Abstract: 2,5-Diketo-D-gluconic acid is prepared in high yield and in high broth concentration by cultivating newly isolated microorganisms of genus Erwinia in an aqueous nutrient medium in the presence of D-glucose. The production is also possible by simple contact of said microorganisms or their processed products therefrom, with D-glucose.

Abstract: A process for separating and recovering minerals, such as molybdenum or coal, from ores with which they occur by addition of a dimercaptothiadiazole to an ore flotation process.

Abstract: Disclosed are flocced mineral materials which may be utilized to prepare high temperature resistant, water resistant articles. These materials are prepared by utilizing, as a starting material, a gellable layered swelled silicate that has an average charge per structural unit that ranges from about -0.4 to -1 and which contains interstitial cations which promote swelling with a source of at least one species of multi-amine derived cations.

Abstract: A process is disclosed for the detection and measurement of wall coke at a specific location in a fluid bed coker through the measurement of the vibrations of the external shell of the coker at that location.

Abstract: In order to provide a substrate such as an optical preform rod (24) which suitable for insertion into a tube and which has a transverse cross section that is substantially circular and disposed concentrically about a longitudinal axis of the substrate substantially along its entire length, a force-applying means such as a graphite roller (52) is adapted to be moved incrementally toward an axis of rotation (35) about which the preform rod is turned rotatably. Movement is discontinued when there is an indication that the force-applying means has been in continuous engagement with the preform rod for at least a predetermined portion of the periphery of the rod. In a preferred embodiment, the engagement of the force-applying means and the preform rod is discontinued after a predetermined time whereafter the force-applying means again is moved toward the axis of rotation.

Abstract: 3-acylamino-1,2,4-triazoles corresponding to the following general formula ##STR1## and 1-acyl-3-amino-1,2,4-triazole corresponding to the general formula ##STR2## in which R is a linear or branched C.sub.1-11 alkyl or phenyl, and mixtures thereof are used as corrosion inhibitors for non-ferrous metals in aqueous systems, oils and oil-containing emulsions.