Abstract: A process for producing boron nitride comprises heating a mixture consisting of borohydride of alkali metal and ammonium chloride at a temperature range of from 800.degree. to 2200.degree. C. in a non-oxidizing atmosphere.

Abstract: Highly monodispersed nonporous spherical SiO.sub.2 particles are prepared having mean particle diameters between 0.05 and 10 .mu.m with a standard deviation of not more than 5% and a method for the preparation of such particles. The particles can be produced by a two step process wherein first a sol of primary particles is prepared by hydrolytic polycondensation of tetraalkoxysilanes in an aqueous/alcoholic ammoniacal medium. The SiO.sub.2 particles are then converted to the desired particle size by a continuous measured addition of tetraalkoxysilane or organotrialkoxysilane controlled by the extent of the reaction. The SiO.sub.2 particles produced by this process are particularly useful as sorption material in chromatography.

Abstract: A process of producing a silanic or siloxanic compound containing at least one cycloalkyl ring by hydrogenation of a corresponding compound containing at least one aromatic ring, in solution, in the presence of a catalyst comprising palladium, supported on active carbon and at a pressure equal to or higher than 10 bar.

Abstract: Zeolite particles retaining at least one metal ion having bacteriostatic properties on their ion-exchangeable sites in an amount up to 41% of the zeolite's ion exchange capacity are described.

Abstract: A method of producing an exhaust gas sensor incorporating BaSnO.sub.3. Stannate ion and barium ion are reacted in a strong alkali to precipitate water-containing crystals of BaSnO.sub.3 such as BaSnO.sub.3.3H.sub.2 O, BaSnO.sub.3.5H.sub.2 O or the like. When thermally decomposed, the precipitate gives BaSnO.sub.3 free from segregated Ba and Sn elements. The product was then molded and thereafter sintered to obtain the sensor.

Abstract: Zeolite particles retaining silver ions having bacteriostatic properties on their ion-exchangeable sites in an amount up to 41% of the zeolite's exchange capacity are described.

Abstract: A composite fused quartz material is disclosed for processing semiconductor grade silicon material in an improved manner. The modified vitreous material includes a disperse phase of fine size silicon metal particles which are distributed in preselected regions of the fused quartz matrix as a means of exercising temperature control in the various semiconductor processing operations using these fused quartz parts. Such utilization of the modified vitreous material in single crystal silicon rod growth and production of semiconductor grade silicon by diffusion doping is described. A method to produce the modified vitreous material is also disclosed.

Abstract: A crystalline zeolite SSZ-26 is prepared using a hexamethyl [4.3.3.0] propellane-8,11-diammonium cation as a template. Also disclosed is a process for converting hydrocarbons with crystalline zeolite SSZ-26.

Abstract: In performing a solution growth of a Group II-VI compound semiconductor crystal by relying on the temperature difference technique under controlled vapor pressure on a solution growth apparatus having a recrystallizing zone, a source crystal supply zone and a vapor pressure controlling zone enclosed in a growth quartz tube and placed under different temperatures for the respective zones, wherein a heat sink is provided at the bottom end portion of the recrystallizing zone to cause a thermal flow to pass therethrough to the outside of the whole apparatus to insure that a single crystal will grow from this bottom end portion of the zone. The quartz tube may be enclosed in a pressure-resistant tube to apply a pressure to the growth quartz tube externally thereof to avoid its destruction to enable the growth to be performed at a high temperature to obtain a high growth rate. Thus, a large size crystal having a good crystal perfection can be grown.

Abstract: Ammonia synthesis gas is made from a raw gas comprising hydrogen, carbon dioxide and medium boiling point gases including nitrogen in excess of the proportion required an ammonia synthesis gas, by a pressure swing adsorption process characterized by feeding to the absorbent a raw gas in which hydrogen and total medium boiling point gases are present in a volume ratio in the range 1.25 to 2.5, and the medium boiling point gases comprise nitrogen to the extent of at least 90% v/v on the total of such gases. Preferred ways of making the raw gas, of ensuring purity of the product gas and of recovering useful heat are described.

Abstract: A method for producing graphite structures which are of light weight and excel in elasticity from a carbonaceous material comprises in succession the steps of: (a) treating said carbonaceous material with nitric acid or a nitric-sulfuric acid mixture, (b) bringing the acid-treated carbonaceous material into contact with a basic aqueous solution to make it soluble, (c) adding an acidic aqueous solution to the obtained soluble matter to regulate the pH of said soluble matter to 3 or less, thereby precipitating a carbonaceous component therefrom, and (d) graphitizing the thus precipitated carbonaceous component at 2,400.degree. C. or higher temperature.

Abstract: Disclosed is a process for the purification of an exhaust gas which contains dust and gaseous pollutants, such as SO.sub.2, SO.sub.3, HCl, HF and nitrogen oxides. In the process 70 to 90% of the total amount of sorbent required is introduced as a dry powder into the gas stream and the remaining 10 to 30% of the sorbent is introduced into the gas stream as a solution or suspension after a turbulence has been induced in the gas stream.

Abstract: Methods are described for preparing aluminum nitride of controllable morphology for ceramic and heat conduction applications. The methods comprise forming spherical particles or flakes of an intermediate, RA1NH, followed by heating the spheres or flakes of RA1NH at elevated temperatures to produce high purity aluminum nitride of corresponding morphology. Spheres of RA1NH are formed by (i) freezing a suspension of RA1NH in a liquid medium and thawing, by (ii) aging the suspension, or by (iii) dissolving RA1NH in a liquid medium and precipitating it. Flakes are formed by freezing a suspension of RAINH in a liquid medium and removing frozen medium from the frozen suspension.

Abstract: Carbon monoxide is reacted with water vapor and converted into hydrogen and carbon dioxide, in the presence of a thio-resistant catalyst which comprises an active phase deposited onto a support, said active phase comprising molybdenum, vanadium or tungsten, and a cobalt and/or nickel promoter therefor, and said support comprising cerium oxide or zirconium oxide. The reaction mixture advantageously includes carbon monoxide, hydrogen, water and compounds of sulfur, wherefrom hydrogen is selectively produced in increased amounts.

Abstract: A continuous process is indicated for complete removal of organic impurities from and complete decolorization of pre-purified wet-process phosphoric acid which has been purified by an extractive method using an organic solvent, freed from residual hydrofluoric acid by steam stripping and treated with hydrogen peroxide at elevated temperature, which comprises mixing the pre-purified wet-process phosphoric acid and the hydrogen peroxide in a mixing zone at a temperature of from 100.degree. to 200.degree. C., preferably 140.degree. to 160.degree. C., and allowing them to react at this temperature for a further 1 to 4 hours, cooling to from 85.degree. to 90.degree. C. the pre-purified wet-process phosphoric acid treated in this way and pumping it at this temperature with exclusion of air firstly through an activated charcoal bed which has been prepared on the basis of peat and has been steam-activated and has a BET surface area of from 800 to 1000 m.sup.

Abstract: A method of manufacturing calcium phosphate using phosphorus in plants. The method comprising the steps of firstly slurrying raw material containing phosphorus, including plants particularly such as soybean, corn, oil meal of the rice bran and the like; adding one or more selected among oxide, hydroxide and carbonate of calcium to the slurry and mixing them; controlling Mg component derived from the raw material so that the Mg/Ca mole ratio is in the range of 0.25 or less; dehydrating and drying them; controlling pH of the slurry and 7.5 or higher and slowly heating them within the temperature range from 150.degree. C. to 650.degree. C. in the oxidation atmosphere to dissipate and remove carbon; and finally raising the temperature to burn them within the temperature range from 700.degree. C. to 1550.degree. C. in the oxidation atmosphere.

Abstract: A method for producing a high yield of free-flowing alpha-phase single crystal silicon carbide platelets. Through the use of various parameter and composition values, the size range of the platelets can be controlled. For example, small size platelets can be prepared by first heating a mixture of finely divided silicon dioxide and carbon to a temperature of about 1600.degree..+-.100.degree. C. for a duration of about 5-10 hours to produce a silicon carbide product, referred to as a "prefire" product. This prefire product is mixed with a platelet-enhancing material in the form of powdered carbon or aluminum metal (and mixtures thereof) and then further heated to about 1900.degree.-2400.degree. C. for 2-10 hours to make the platelets. Also, small platelets can be made by substituting silicon carbide whiskers for the intermediate prefire material and adding a platelet enhancing material.

Abstract: The synthesis of ammonia from hydrogen and nitrogen is carried out in a process scheme in which a liquid material is provided to react with ammonia to form an ammine to either improve the method of recovery of ammonia from a product gas stream or to upset the thermodynamic equilibrium of the H.sub.2 --N.sub.2 --NH.sub.3 system so that higher first pass conversion of the reactant gas to ammonia can be accomplished. As a result of this invention the horsepower of the synthesis gas compressor, the catalyst inventory, the operating temperature, and the operating pressure, or combinations of these factors, are reduced, having the effect of decreasing equipment and operating costs. In addition, the liquid ammine product is decomposed under conditions that allow the recovery of the ammonia as a liquid product by heat exchange with cooling water. This markedly reduces refrigeration horsepower requirements.

Abstract: Carbon monoxide is reacted with water vapor and converted into hydrogen and carbon dioxide, in the presence of a thio-resistant catalyst which comprises an active phase deposited onto a support, said active phase comprising molybdenum, vanadium or tungsten, and a cobalt and/or nickel promoter therefor, and said support comprising cerium oxide or zirconium oxide. The reaction mixture advantageously includes carbon monoxide, hydrogen, water and compounds of sulfur, wherefrom hydrogen is selectively produced in increased amounts.

Abstract: A process for producing monosilane, which comprises disproportionating an alkoxysilane of the formula:H.sub.n Si(OR).sub.4-n (I)wherein R is an alkyl group having from 1 to 6 carbon atoms or a cycloalkyl group and n is an integer of 1, 2 or 3, in the presence of a catalyst, wherein the catalyst comprises at least one compound selected from the group consisting of aromatic alkoxides of the formula:MOAr (II)wherein M is a metal of Group Ia of the Periodic Table and Ar is a substituted or unsubstituted aromatic hydrocarbon group, and quaternary ammonium and phosphonium compounds of the formula:R.sup.1 R.sup.2 R.sup.3 R.sup.4 ZX (III)wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 which may be the same or different, is a substituted or unsubstituted alkyl or aryl group, Z is a nitrogen atom or a phosphorus atom and X is an anion.