Abstract: Disclosed is a catalyst for hydrotreating a coal liquefaction and circulation solvent, in which .gamma.-alumina carrier carries at least one metal of Group VI of the Periodic Table in an amount of from 15 to 15% by weight as the oxide thereof and at least one metal of Group VIII of the same Table in an amount of from 3 to 10% by weight as the oxide thereof and the pore distribution as measured by mercury pressure porosimetry satisfies the conditions that the pores having a diameter of from 40 to 600 .ANG. have a mean diameter of from 9 to 150 .ANG. and the capacty of the pores having a diameter falling within the range of the mean diametr plus/minus 10 .ANG. is 65% or more of the capacity of the pores having a diameter of from 40 to 600 .ANG.. The catalyst is highly active for both hydrogenation and denitrogenation of coal-liquefying solvents.

Abstract: A sintering metal powder consisting of metal particles having a particle diameter distribution including a plurality of peaks. The larger of the two particle diameters at every adjoining two, respectively, of the peaks has a ratio of between 5 and 10 to the smaller. The height of one of every adjoining two of the peaks has a ratio of between 1 and 5 to that of the other that is not higher than the one peak. The particle diameter at one of every adjoining two of the peaks which is not higher than the other is smaller than that at the other peak. The particle diameter at the highest peak is between 30 and 80 microns. A process for making a sintered product from such a powder is also disclosed.

Abstract: An alloy target for magneto-optical recording having component and composition comprising 10 to 50 atom % of at least one rare earth element from Sm, Nd, Gd, Tb, Dy, Ho, Tm and Er, the balance being substantially at least one transition metal from Co, Fe and Ni, and having a mixed structure comprising a phase of intermetallic compound of the rare earth element and the transition metal and a fine mixed phase of the rare earth element and intermetallic compound of the rare earth element and the transition metal or having a mixed structure comprising the structure above and a phase of the rare earth element alone. The target has uniform composition and high strength free from cracking, etc., shows less composition difference between film and target and less change of the film composition with elapse of sputtering time.

Abstract: An alloy target for making a magneto-optical recording medium by sputtering comprises an alloy containing 10 to 50 atom % of at least one rare earth element selected from among Sm, Nd, Gd, Tb, Dy, Ho, Tm and Er, with a balance consisting substantially of at least one transition metal selected from among Co, Fe and Ni. The alloy has a mixed structure composed of at least three phases of intermetallic compounds formed by the rare earth element and the transition metal.

Abstract: An alloy target for making a magneto-optical recording medium by sputtering comprises an alloy containing 10 to 50 atom % of at least one rare earth element selected from among Sm, Nd, Gd, Tb, Dy, Ho, Tm and Er, with a balance consisting substantially of at least one transition metal selected from among Co, Fe and Ni. The alloy has a mixed structure composed of at least one phase of an intermetallic compound formed by the rare earth element and the transition metal and a phase of the rare earth element along.

Abstract: High-purity uranium can be effectively recovered from gadolinium-containing nuclear fuel scraps by dissolving the scraps in a mineral acid, extracting uranium from the resulting solution with a solvent, washing the organic phase with water or a dilute mineral acid, and counter-extraction with water or a dilute mineral acid. This invention also provides an efficient method of recovering high-purity gadolinium from the acidic washings coming from the above washing step and containing small amounts of radioactive elements (uranium, thorium and others) by adding an alkali, removing the precipitate thus formed, lowering the pH of filtrate to 2 or less, and adding an oxalic acid source to precipitate gadolinium oxalate.

Abstract: Supported catalysts for hydrotreating hydrocarbons comprise (a) at least one member selected from the group consisting of oxides of metals in Groups IV and VIII of the Periodic Table, and (b) at least one organic compound having a mercapto radical or radicals (--SH) selected from the group consisting of mercapto-carboxylic acids, including alkali metal, alkaline earth metal and ammonium salts thereof and esters thereof, bivalent mercaptans, amino-substituted mercaptans, and thiocarboxylic acids. These catalysts can be easily activated by treatment in the presence of hydrogen gas at a temperature in the range from room temperature to 400.degree. C. show higher activity than catalysts activated by conventional methods.

Abstract: A dielectric ceramic which has a composition represented by the following general formula (I) and having a substantially perovskite crystal structure:(Ba.sub.1-x Sr.sub.x) (Mg.sub.1-y-w Ni.sub.y Co.sub.w).sub.1-u (Ta.sub.1- Nb.sub.z).sub.u 0.sub.p (I)wherein x, y, z, u, w and p satisfy one selected from the following conditions: x=0, w=0, z=0, 0.001.ltoreq.y.ltoreq.0.088, 0.66.ltoreq.u<0.72, and p represents a number with which the charges of the cations of Ba, Mg, Ni and Ta are neutralized, whereby the entire composition is electrically neutralized; x=0, z=0, 0.001.ltoreq.y.ltoreq.0.40, 0.001.ltoreq.w.ltoreq.0.40, 0.61.ltoreq.u.ltoreq.0.72, 0.002.ltoreq.y+w.ltoreq.0.40 and p represents a number with which the charges of the cations of Ba, Mg, Ni, Co and Ta are neutralized, whereby the entire composition is electrically neutralized; x=0, w=0, 0.04.ltoreq.y.ltoreq.0.90, 0.10.ltoreq.z<0.96, 0.61.ltoreq.u.ltoreq.0.

Abstract: A method of operating a flash smelting furnace which includes a reaction shaft, a concentrate burner disposed at the top of the reaction shaft, a settler disposed with one end thereof connected to the lower part of the reaction shaft, an uptake disposed as connected to the other end of the settler, and at least one lance pipe disposed through the ceiling of the settler between the reaction shaft and the uptake and adapted to permit forced supply of at least powdery raw materials and a reaction gas into the melt in the settler includes the steps of blowing the powdery raw materials containing only a small amount of incombustible substances and the reaction gas into the reaction shaft through the concentrate burner, blowing powdery raw materials containing at least incombustible substances through the lance pipe, and employing means capable of at least retaining the heat of the melt.

Abstract: A flash smelting furnace which comprises a reaction shaft, a concentrate combustion device disposed at the top of the furnace shaft, a settler disposed with one end thereof connected to the lower part of the reaction shaft, an uptake disposed as connected to the other end of the settler and at least one lance pipe extending through the ceiling of the settler between the reaction shaft and the uptake and adapted to blow at least powdery raw materials and a reaction gas into the melt inside the settler.

Abstract: A dielectric ceramics comprises a complex oxide having a perovskite-type crystal structure, the complex oxide substantially having the composition represented by the following general formula (I)(Ba.sub.(1-x) Sr.sub.x){(Mg.sub.(1-y) Zn.sub.y).sub.1/3 ( -Ta.sub.(1-z) Nb.sub.z).sub.2/3 }O.sub.3 (I)wherein x, y and z are numbers represented respectively by the expressions 0<x<1, 0<y<1, and 0<x<1. The temperature coefficient of the resonant frequency of the ceramics can be freely changed by adjusting the x value.

Abstract: A dielectric ceramics possessing a high level of unloaded Q and low loss at high frequency beneficial for communications at high frequency is produced by a method which comprises heating a green compact of a composition represented by the general formula: xBaO.yMgO.zTa.sub.2 O.sub.5 (wherein x, y, and z satisfy 0.5.ltoreq.x.ltoreq.0.7, 0.15.ltoreq.y.ltoreq.0.25, 0.15.ltoreq.z.ltoreq.0.25, and x+y+z=1) to a temperature in the range of 1,500.degree. to 1,700.degree. C. at a temperature increasing rate of 100.degree. to 1,600.degree. C./minute and subsequently retaining the green compact at the temperature for not less than 30 minutes.

Abstract: A method of treating the slag from a copper converter comprises introducing the molten slag from a copper converter into a furnace having tuyeres through which air can be blown into the molten slag, blowing into the slag through the tuyeres at least 6% by weight of pulverized coal with air or oxygen-enriched air having an oxygen content of 21 to 40% by volume to separate molten metallic copper from the slag, the amount of the air having a ratio of 0.3 to 0.7 to theoretical combustion of the coal, adding a source of sulfur to the separated copper to form a molten matte, maintaining the matte at a reduced pressure not exceeding 0.6 mm Hg for at least five minutes in a vacuum refining apparatus to remove impurities from the matte by volatilization, and treating the refined matte in a copper converter used for the treatment of a matte produced by a smelting furnace.

Abstract: A silicate ore containing gold and silver is melted with the slag from a copper converter and a reducing agent. A source of CaO may also be added to the slag so that the treated slag may contain at least 3.0% by weight of CaO. Copper is recovered from the slag and absorbs gold and silver from the ore. This method drastically improves the capacity for the treatment of a silicate ore containing gold and silver during the smelting of copper. It enables the complete melting of the ore without leaving any ore undissolved.

Abstract: Dielectric ceramics represented by the following general formula and substantially having the K.sub.2 NiF.sub.4 type crystal structure,aSrO.bCaO.cTiO.sub.2.dSnO.sub.2(wherein 0.39.ltoreq.a.ltoreq.0.70, 0.ltoreq.b.ltoreq.0.28, 0.27.ltoreq.c.ltoreq.0.35, 0.ltoreq.d.ltoreq.0.04, and a+b+c+d=1), have a high dielectric constant and an unloaded Q as high as 6000 and more in the high-frequency region of super high frequency band, and are therefore best suited for use in dielectric resonators, dielectric substrates for micro wave integrated circuit, and the like.

Abstract: A rare earth-element/cobalt type magnetic powder which possesses outstanding magnetic properties and which is useful for making a resin magnet is produced by a method which comprises thermally reducing a mixture consisting of oxide of samarium, oxide of praseodymium, optionally oxide of neodymium, and cobalt powder, thereby causing diffusion of consequently produced samarium, praseodymium, and/or neodymium in the cobalt powder, subjecting the resultant reaction product to a heat-treatment involving standing at 600.degree. to 900.degree. C. for 30 minutes to 5 hours and subsequent quenching from this temperature at a rate of not less than 10.degree. C./minute, adding the product of the heat-treatment to water, thereby converting the product into a slurry, treating the slurry with water and an aqueous acid solution, and comminuting the resulting powder into particles of an average diameter of 3 to 10 .mu.m thereby obtaining a magnetic powder having a composition represented by Sm.sub.1-x Pr.sub.x Co.sub.

Abstract: An optical branching element mainly composed of a central linear optical transmission line and a plurality of peripheral linear optical transmission lines. They have circular sections of approximately the same diameters. The peripheral linear optical transmission lines are provided around the central linear optical transmission line such that their end surfaces are arranged on the same plane as the end surface of the central linear optical transmission line. A holder fixes these central and peripheral linear optical transmission lines on the end surface side. Semispheric reflecting concave surfaces having radii larger than the diameters of said peripheral linear optical transmission lines are formed around the contact points of the end surface of the central linear optical transmission line and the end surfaces of the linear optical transmission lines.

Abstract: An alloy metal powder which contains rare earth metals and which has a uniform composition and contains a minimum of residual reducing agent and oxygen is produced by (1) preparing a mixture composed of (a) a powder of rare earth metal oxide, (b) a powder of a metal which is difficult to volatize at 900.degree. to 1300.degree. C., (c) at least one reducing agent selected from alkali metals, alkaline earth metals, and hydrides thereof, and (d) at least one chloride selected from alkali metal chlorides and alkaline earth metal chlorides, (2) heating the mixture in an inert gas atmosphere or under vacuum to provide a reaction mixture, and (3) treating the reaction mixture by a wet process.

Abstract: The invention involves a selectively plating apparatus for forming an annular area.The apparatus is particularly characterized by including the inner and outer mask members which cooperate to define the annular areas to be coated. It enables the automatic operation for forming the annular coated areas and is very effective for the mass production of, for example, lead frames.

Abstract: Finely-divided particulate bismuth oxide is produced by the steps of heating bismuth at 800.degree. C. or above in a first compartment of a sealed vessel divided into two compartments by a partition wall, the two compartments communicating with each other by a hole provided on the partition wall, feeding an inert gas such as nitrogen and argon into the first compartment so that the bismuth vapor formed by heating bismuth has a bismuth concentration of 0.1 to 0.5 g/liter, blowing air into the bismuth vapor introduced from the first compartment into the second compartment through the hole on the partition wall, permitting the air to mix with the bismuth vapor to form bismuth oxide and simultaneously cooling the thus formed bismuth oxide to 250.degree. to 300.degree. C., discharging by suction the bismuth oxide from the sealed vessel at a flow rate of 1 to 5 m/sec, and cooling the discharged bismuth oxide by supplying cooling air outside the sealed vessel.