Abstract: A tool for grinding and polishing diamond and a method for polishing diamond in which a single crystal diamond, a diamond thin film, a sintered diamond compact and the like can be polished at low temperatures without causing cracks, fractures or degradation in quality therein. The tool and method provide a polishing operation which is easy to accomplish, provides stable polishing quality, and provides decreased costs while maintaining stable grinder performance. The grinder is formed of a main component which is an intermetallic compound consisting of one kind or more of elements selected from the group of Al, Cr, Mn, Fe, Co, Ni, Cu, Ru, Rh, Pd, Os, Ir and Pt and one kind or more of elements selected from the group of Ti, V, Zr, Nb, Mo, Hf, Ta and W. The diamond polishing method includes pushing the above stated grinder against the diamond, and rotating or moving the grinder relative to the diamond while keeping the portion of the diamond subjected to polishing at room temperature.

Abstract: A sedimentation apparatus for precipitating and separating suspended solids and coagulated flocs in a liquid to be treated, so as to clarify the liquid. The sedimentation apparatus comprises a mixing chamber secured within a sedimentation tank, for mixing and stirring the liquid and an additive; and a rotary support of a distributor, functioning as a bottom of the mixing chamber, rotatable about the center axis of the mixing chamber. The bottom portion of the rotary support is formed with an opening. The sedimentation apparatus has a blade for discharging from the opening the precipitate deposited on the bottom of the rotary support. As a consequence, the precipitate can be prevented from accumulating in excess in the rotary support.

Abstract: A sedimentation apparatus for precipitating and separating suspended solids and coagulated flocs in a liquid to be treated, so as to clarify the liquid. The sedimentation apparatus comprises a mixing chamber secured within a sedimentation tank, for mixing and stirring the liquid and an additive; and a rotary support of a distributor, functioning as a bottom of the mixing chamber, rotatable about the center axis of the mixing chamber. The bottom portion of the rotary support is formed with an opening. The sedimentation apparatus has a blade for discharging from the opening the precipitate deposited on the bottom of the rotary support. As a consequence, the precipitate can be prevented from accumulating in excess in the rotary support.

Abstract: A graft copolymer of: an organic solvent soluble fluoropolymer having at least one urethane linkage and containing at least one radically polymerizable bond; at least one polysiloxane having a radically polymerizable terminal group; at least one monomer having a radically polymerizable double bond and a fluoroalkyl group per monomer molecule; and at least one different radically polymerizable monomer. Compositions containing this graft copolymer composition are suitable for use as a coating having water repellent, oil repellent and stain resistant properties over a long period of time.

Abstract: A medium-carbon steel is provided having a dispersed fine spherical graphite structure, having high mechanical strength, good processability, and good machinability, and having fine ZrC functioning as nucleation sites for graphite. The medium-carbon steel having a dispersed fine spherical graphite structure is manufactured by providing a composition containing 0.1 to 1.5% Si, 1.0% or less C, and 0.01 to 0.5% Zr. After the composition or a material of the composition (ingot) has been hot-rolled, or after the hot-rolled steel has been heat-treated at 750 to 1300° C. for 0.5 to 10 hours (solution heat treatment) after hot-rolling, or after the hot-rolled and heat-treated steel has further been water-quenched to deposit fine ZrC particles in the matrix, the steel is subjected to graphitization treatment by heat-treating at a temperature of 740° C. or below for 0.5 to 100 hours to grow graphite using ZrC as the nucleation site.

Abstract: The methods of the present invention provide efficient mechanical milling or alloying of stock materials of titanium and aluminum in order to increase yield of the titanium stock and reduce cost in connection with the production of a titanium-aluminum-based alloy sinter. Sponge titanium, which has a particle size of 1 to 20 mm and which contains hydrogen at 3.5 mass % or more, is used as the titanium stock. The sponge titanium is ball-milled with an aluminum stock in an argon atmosphere to produce a hydrogen-containing titanium-aluminum-based alloy powder. Furthermore, this powder may be sintered, as required.

Abstract: A unique method is proposed for the preparation of a body of an austempered ductile cast iron having a gradient of the mechanical property within the body by subjecting a body of a nodular graphite cast iron to an isothermal transformation treatment for austempering at a temperature in the range from 250.degree. to 450.degree. C. while the body has a temperature difference between two points or between two surfaces. The temperature difference can be produced by bringing the two points or two surfaces into contact with melts of a salt kept at different temperatures. A two-compartment salt-bath apparatus therefore is disclosed.

Abstract: An improved method is proposed for the image information of a body by ultrasonic scanning in which the resolution of the image can be greatly improved without sacrifice in the penetrability of the ultrasonic waves, i.e. without increasing the ultrasonic frequency, into the body under inspection.The improvement comprises:attaching a central ultrasonic absorber to the ultrasonic objective lens of the ultrasonic probe; andinserting an auxiliary concave lens between the ultrasonic probe and the body under inspection.