Abstract: Optical waveguide having a fused silica core and a fluorine doped silica cladding is made by heating a cylinder of silica in fluorine, the cylinder initially having an outer annular particulate or porous region which is dried by the fluorine and into which fluorine diffuses to lower the refractive index of the silica when fused. The cylinder is made by depositing particulate silica onto a mandrel, drying the silica in chlorine, and heating the silica to densify it. Further particulate silica is deposited and is then heated in a fluorine-containing gas to dry, fluorine diffuse, and sinter the porous outer part of the silica. The resulting tubular silica preform is heated to collapse the tubular preform into a rod from which optical waveguide is drawn, the waveguide having a fluorine doped silica cladding.

Abstract: There is disclosed a method of dewatering porous 96% silica glass by impregnating the glass pores with an aqueous solution of a water-soluble, nitrogen-containing, organic compound that is thermally decomposable to produce reactive gaseous nitrogen species, and then thermally decomposing the impregnating compound to yield nitrogen which combines with the glass to oust hydroxyl group. A preferred material is guanidine hydrochloride, and a non-oxidizing atmosphere is maintained during heating to avoid nitrogen oxidation. The nitrided porous glass may subsequently be thermally consolidated to a non-porous body.

Abstract: A transparent BN-type ceramic material comprising 10 to 40 wt. % of boron (B), 35 to 55 wt. % of nitrogen (N) and 3 to 40 wt. % of silicon (Si) as the main component elements, and 1 to 10 wt. % of sub-component elements, with the property of not being crystallized by heat treatment at 1600.degree. C. for one hour, and a method of producing the above ceramic material by reacting a boron-containing compound, a nitrogen-containing compound and a silicon-containing compound at deposition temperatures in a range of more than 1300.degree. C. to less than 1700.degree. C. with the total gas pressure within a reaction furnace maintained in the range from 10 Torr to 100 Torr by use of a chemical vapor deposition method are disclosed.

Abstract: A segmenting and dehydration process for fruits and vegetables with a primary application as a process for producing dehydrated filaments of sugar beets as a natural sweetener for use by confectioners, bakeries, breweries and other food processors. The beets are washed, shredded with a high-speed heated blade and immediately dried in a continuously sterile atmosphere that prevents bacteria contamination and growth and enzyme action which otherwise result in an unacceptably strong flavor in the finished product.

Abstract: A method for increasing the efficiency of the caustizing process which comprises: (a) adding to a green liquor between 78 and 82% of the stoichiometric amount of lime necessary to react with the amount of Na.sub.2 CO.sub.3 present in the green liquor to obtain a white liquor containing NaOH and lime mud. The white liquor is then clarified by extracting the lime mud present to obtain a white liquor having a total solid concentration of about 10-60 grams/liter. The supernatant liquid of the white liquor is treated with an additional amount of lime to increase the causticity to about 87%, then allowing further causticizing reaction between the lime and Na.sub.2 CO.sub.3. The remaining lime mud present is removed to obtain a white liquor which has the causticity of about 87%. One is thus able to raise the causticity of partially clarified white liquor following the normal causticizing process, the mud present being sufficient to increase causticity without substantially decreasing settling rate.

Abstract: The froth flotation of coal is conducted in the presence of a conditioner of an oxygen containing compound of the formula:R.sub.1 --O--R.sub.2).sub.n (I)wherein R.sub.1 and each R.sub.2 are independently saturated hydrocarbyls and n is from 1 to about 3.

Abstract: A column comprising an insoluble carrier and an anti-.beta..sub.2 -microglobulin antibody immobilized to the carrier can specifically adsorb and remove .beta..sub.2 -microglobulin in the blood. This column is useful for the prevention and treatment of diseases such as carpal tunnel syndrome observed in patients undergoing blood dialysis.

Abstract: A process is disclosed for the preparation of milled crude potash salts containing kieserite, whereby the crude potash salt is conditioned at first with a chemical conditioning agent and subsequently with an auxiliary conditioning agent, whereupon the crude potash salt is fed to an electrostatic free fall separator.

Abstract: A spherical silica glass powder particle having projections of network pattern on its surface is produced by gel-route formation.

Abstract: A method of preparing an optical device for alignment with a light beam emitter or receiver. The optical device is formed of a first glass that is resistant to dissolving in a given solvent. Extending through the device is an optical waveguide at least the cladding of which is soluble in the given solvent. At least one end of the device is immersed in the solvent to dissolve the end portion of the fiber and form a well. An optical fiber is inserted into the well where it is aligned with the fiber extending through the device.

Abstract: A method for producing a glass preform for an optical fiber by means at least two burners, comprising jetting a glass raw material containing SiCl.sub.4 from the first center burner and a hydrogen-containing silicon compound with larger reaction heat than SiCl.sub.4 from at least one second burner, flame hydrolyzing the glas raw material to synthesizing fine glass particles, depositing the fine glass particles on a starting member to form a porous soot preform and heating and sintering the soot preform to obtain a transparent glass preform, by which a large preform is stably produced and a bulk density of the preform is easily controlled.

Abstract: A planar lightwave guide with light-conducting core zones in light conducting strips is made by the precipitation out of a gaseous phase onto a substrate a thin, glass-like strata in accordance with a programmed schedule so as to allow a predetermined refractive index curve to be obtained to thereby form a light-conducting core zone and protective sheathing layers adjacent to the core zone. The improvement in the method is characterized in that the precipitation out of the gaseous phase is obtained by application of a heterogeneous reaction and in that after the formation of the light-conducting strips, the refractive index of the core-forming strata is modified in a targeted manner in a lateral marginal region of the strips by diffusing out the doping substance which determines the refractive index curve in the core zones. Subsequently these strips and the substrate are coated with a covering layer of a material having a lower refractive index than that of the core zone material.

Abstract: A method for obtaining a purified fraction from a mixture using a magnetic fluid wherein the mixture is contacted with the magnetic fluid to preferentially sorb the fluid onto selected components so they become magnetized and the magnetic components in the so-contacted mixture are separated from the nonmagnetic components by passing the mixture through a magnetic field. The method finds particular use for obtaining a purified sample of crop seed from a mixture of crop seed and soil of the same size and texture and for separating nut shells from nutmeats.

Abstract: A method for manufacturing hollow core optical fibers is disclosed comprising continuously feeding a glass rod of the desired cladding composition into a high temperature furnace with the rod in line contact with the inner surface of the glass tube. The glass transition temperature of the rod is substantially lower than the glass transition temperature of the glass tube. The glass rod composition is uniformly distributed on the glass tube inner wall as it enters the furnace hot zone. The ratio of the rod diameter to the glass tube inner diameter and the drawing temperature determine the coating thickness of the glass cladding on the inner surface of the glass tube. As the coated tube is passed through the furnace hot zone peak, the optical fiber is drawn. The rod and tube feed rate, the drawing temperature of the rod and glass tube and the drawing rate of the coated glass tube are selected to yield a hollow core optical fiber, with preselected interior and exterior diameters.

Abstract: Etching solutions used to etch, for example, silicon dioxide coated substrates in the manufacture of integrated circuits comprise an aqueous solution of ammonium fluoride and a wetting amount of a nonionic alkylphenol polyglycidol ether having the formula: ##STR1## wherein R is an alkyl group having from about 4 to about 12 carbon atoms, and x is from about 3 to about 15. The etching solutions preferably contain hydrogen fluoride in a volume ratio of NH.sub.4 F to HF of from about 3:1 to about 50:1. The novel etching solutions of the present invention have excellent wetting characteristics, will not incorporate metallic ions, and retain their wetting properties after extended periods of continuous filtration.

Abstract: The speed at which optical fibers can be drawn and coated is significantly increased by efficiently stripping the gas boundary layer entrained by the moving fiber. The stripping is periodically repeated to ensure that the entrained flow is not re-established.

Abstract: Etching solutions used to etch, for example, silicon dioxide coated substrates in the manufacture of integrated circuits comprise an aqueous solution of ammonium fluoride and a wetting amount of a nonionic alkyl polysaccharide having the formula:RO(R'O).sub.x Z.sub.ywherein R is alkyl, alkylphenol, hydroxyalkyl, hydroxy alkylphenol, or mixtures thereof and said alkyl groups contain from about 6 to about 18 carbon atoms, R' contains from 1 to about 4 carbon atoms, x is from 0 to about 5, Z is a moiety derived from a reducing saccharide containing from 5 to 6 carbon atoms, and y is from about 1 to about 5. The etching solutions preferably contain hydrogen fluoride in a volume ratio of NH.sub.4 F to HF of from about 3:1 to about 50:1.The novel etching solutions of the present invention have excellent wetting characteristics, will not incorporate metallic ions, and retain their wetting properties after extended periods of continuous filtration.

Abstract: A shutter device for use in an etching apparatus using charged particles, which includes at least one sheet-like electrode having an aperture for passage of the charged particles; and a voltage source for selectively applying to the electrode an electric voltage so as to establish at the electrode an electric potential higher than that of the charged particles; wherein the passage of the charged particles through the aperture of said electrode is prevented when the electric potential which is higher than that of the charged particles is established at the electrode by the voltage application by the voltage source.

Abstract: A device for simultaneously separating cohesively bonded particles, by the action of a turbulent air stream, and classifying them according to their size, the device has a horizontal hood connected to the upstream and downstream air ducts. Equipped with an air fan, the upstream air duct has a converging section to accelerate a stream of air. Feed hoppers distribute the particles into the upstream end of the hood where they are separated and classified. Collecting devices are below the hood to receive the classified particles. A recirculating air duct is disclosed including a built-in filter device. A method is also disclosed for simultaneously separating cohesively bonded particles and classifying them according to their size.

Abstract: A series of water-dispersible and oil-dispersible corrosion inhibiting solutions are disclosed which contain a polythioether represented by the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are H, a methyl group, or an ethyl group, X is a divalent organic radical selected from the group consisting of --C.sub.2 H.sub.4 --, --C.sub.4 H.sub.8 --, --C.sub.2 C.sub.4 OC.sub.2 H.sub.4 --, and C.sub.2 H.sub.4 SC.sub.2 H.sub.4 --, n is about 2 to about 40, and p is 0 or 1. The corrosion inhibitor solvent is preferably a hydrocarbon, such as an aromatic solvent or an alcohol, but may be water. Metal equipment can be protected through the use of the invention corrosion inhibiting solutions by contacting metal with an effective amount of inhibiting solution containing the polythioethers in a continuous exposure or batch treatment.