Abstract: A slurry contains MnO.sub.2 or other manganese oxide as a primary component of abrasive particles. Further, a polishing process using such a manganese oxide abrasive and a fabrication process of a semiconductor device using such a polishing process are disclosed.

Abstract: Black ultrafine magnetite particles of this invention have an FeO content of 31 to 35% and a particle size of 0.1 .mu.m or less. A process for producing the black ultrafine magnetite particles comprises dispersing ultrafine magnetite particles with a particle size of 0.1 .mu.m or less in water containing ferrous hydroxide, aging the dispersion of 90 to 200.degree. C. at a free alkali concentration of 1 mol/liter (M/l) or more, then adding 0.2 to 5%, based on the magnetite particles, of sodium oleate or potassium oleate, and adjusting the pH to 5 to 6 to adhere oleic acid to magnetite.

Abstract: A process for producing lithium manganate as a cathode active material for lithium secondary batteries comprising firing raw materials at a rate of temperature rise and/or temperature drop of 150.degree. C./min or more.

Abstract: A fine particulate polishing agent comprises fine particles of a solid solution composed of single-crystal ceric oxide and silicon dioxide and fine particles of silicon dioxide. A slurry polishing agent comprising the fine particulate polishing agent can be prepared by a method which comprises the steps of mixing, with stirring, single-crystal ceric oxide fine particles, silica sol and a liquid; drying the mixture; subjecting the dried particulate material to a thermal treatment at a high temperature and then cooling the solid solution powder formed by the thermal treatment and composed of single crystal ceric oxide and silicon dioxide; again mixing the powder with silica sol and a liquid; and then subjecting the mixture to deagglomeration using a wet pulverizing mill to give a slurry.

Abstract: Cerium oxide ultrafine particles consist essentially of cerium oxide single crystal grains having a grain size ranging from 10 to 80 nm and the cerium oxide ultrafine particles can be prepared by a method which comprises the steps of mixing, with stirring, an aqueous solution of cerous nitrate with a base in such a mixing ratio that the pH value of the mixture ranges from 5 to 10, then rapidly heating the resulting mixture up to a temperature of 70 to 100.degree. C. and maturing the mixture at that temperature. The cerium oxide ultrafine particles not only have an average particle size ranging from 10 to 80 nm, but also are uniform in the particle size and in the shape.

Abstract: A cathodic active material comprises a mixture of graphite particles and electrolytic manganese dioxide particles which are composed of needle-like crystals having an aspect ratio ranging from about 2 to about 20 and an alkaline manganese dioxide cell is provided with a cathode prepared from the cathodic active material. The cathodic active material for dry cells can be prepared by mixing, in advance, carbon powder with manganese dioxide powder in a weight ratio ranging from about 1:100 to about 15:100 and then pulverizing the resulting mixture. The novel cathodic active material for dry cells permits substantial improvement of the resulting dry cell in the high load-discharge quality.

Abstract: According to the present invention, the oxidation of the surface of solder particles is inhibited and the generation of solder balls in the reflow soldering process is inhibited. More specifically, the present invention protects the surface of the solder particles from oxidation during all steps, including the storage of a solder powder, formation of a paste from the solder powder, printing, transferring to a reflow oven and reflow soldering, to minimize the oxidation of the solder particles at these steps so that the generation of solder balls is minimized. In addition, the present invention provides a method for making the solder powder and a solder paste using the solder powder. The objective of the present invention is achieved by the solder powder, the particles of which have on the surface thereof an organometallic compound composed of adipic acid and a metal of the solder alloy. This solder powder is produced by reacting particles of the solder alloy powder with vaporized adipic acid.

Abstract: A fine particulate polishing agent is based on cerium oxide and silicon oxide; a slurry polishing agent comprises the foregoing fine particulate polishing agent which can be prepared by a method which comprises the steps of mixing, with stirring, cerium oxide fine particles, silica sol and a liquid; drying the mixture; mixing the material with a liquid; and then subjecting the mixture to deagglomeration using a wet pulverizing mill to give a slurry. Preferably, the dried particulate material is subjected to a thermal treatment at a high temperature of 150.degree. to 1200.degree. C., preferably 800.degree. to 900.degree. C., thereby to produce a solid solution of cerium oxide and silicon oxide. The slurry polishing agent can ensure the achievement of surface roughness comparable to or superior to that achieved by the colloidal silica polishing agents and a high polishing rate at least comparable to that achieved by the conventional cerium oxide polishing agents.

Abstract: Magnetic particles for perpendicular magnetic recording, which are hexagonal ferrite particles having a hexagonal platelet shape, and are represented by the formula MM'.sub.x M".sub.y Fe.sub.2x-y+2z O.sub.1+4x+3z (wherein M represents at least one element or a combination of elements selected from Ba, Sr, Ca and Pb; M' is at least one element or a combination of elements selected from Co, Zn and Mn; M" is at least one element or a combination of elements selected from Co, Ti, In, Zn, Mn, Ge, Nb, Zr, Ta, V and Sn, x is a number of z/4 to z, inclusive; y is a number of 0 to (x+z)/3, inclusive; and z is a number of 5.5 to 9.0, inclusive), and has an average particle size of from 0.01 to 0.3 .mu.m. The magnetic particles have a novel crystal structure different from both the magnetoplumbite structure and the spinel structure, even internally of the individual particles.

Abstract: Short, fine fibers having certain aspect ratios and generally triangular cross-section are mixed with particulate material whereby the fibers form a three dimensional network and the mixture is sintered to provide composites containing scattered and enveloped particulate material, which composites have utility as self-lubricating materials or grinding materials.