Abstract: It is an object of the present invention to provide a composite material having low thermal expansivity, high thermal conductivity, and good plastic workability, which is applied to semiconductor devices and many other uses.

Abstract: In a joining method for manufacturing a rotor blade by joining a plurality of members, the members are pressed so as to exert a predetermined pressure on the bonding interface, a pulse voltage is applied to the members to pass electric current therethrough, and the joint portion is heated by resistance heating generated at the bonding interface and in the bulk of the members to cause diffusion bonding and thereby to join the members to each other. By this method, good joining can be achieved without substantially changing the crystal structure and mechanical properties of the base metals.

Abstract: The invention provides a friction stir welding apparatus and method and a processing apparatus and method, which are not easily affected by deformations of a work being processed. The friction stir welding apparatus inserts a rotating tool into the work and moves the rotating tool relative to the work to join members of the work. The friction stir welding apparatus and method and the processing apparatus and method of the invention, the latter cutting or grinding the work with a rotating cutter or grindstone, comprises controlling a relative distance between the tool, cutter or grindstone and the work under the joining or processing operation or an insertion depth so that the load factor or electric current of a spindle motor for rotating the tool, cutter or grindstone is within a predetermined range, and a controller therefor.

Abstract: The invention provides a friction stir welding apparatus and method and a processing apparatus and method, which are not easily affected by deformations of a work being processed. The friction stir welding apparatus inserts a rotating tool into the work and moves the rotating tool relative to the work to join members of the work. The friction stir welding apparatus and method and the processing apparatus and method of the invention, the latter cutting or grinding the work with a rotating cutter or grindstone, comprises controlling a relative distance between the tool, cutter or grindstone and the work under the joining or processing operation or an insertion depth so that the load factor or electric current of a spindle motor for rotating the tool, cutter or grindstone is within a predetermined range, and a controller therefor.

Abstract: Reduction of air resistance which acts on the conventional motor-driven blower is limited because crushed protrusions are formed on the surface of the plate of the impeller of the conventional motor-driven blower, and this air resistance is a significant impediment to an increase of the operating speed of the motor-driven blower. Thus, an impeller is provided which comprises a front plate having a suction opening, a back plate disposed opposite to the front plate, and a plurality of blades disposed between the front plate and the back plate. At least either the front plate or the back plate is formed integrally with the blades.

Abstract: A channel box for a nuclear-reactor fuel assembly (MOX fuel assembly) containing plutonium, capable of properly controlling the excess reactivity without mixing neutron absorber or burnable poison into a fuel rod, and a channel box for a nuclear-reactor fuel assembly which does not form any gap between the channel box and members containing burnable poison in the channel box and in which the burnable poison does not directly contact with reactor water.

Abstract: The present invention provides a zirconium based alloy member which has very small deformation of elongation and bow occurring due to irradiation growth, a method of manufacturing it, and particularly an channel box for an atomic reactor fuel assembly. A zirconium based alloy plate member having a width of not less than 100 mm and a long length, containing not more than 5 wt % Nb and/or not more 5 wt % Sn, the member having (0001) orientation (Fl value) of hexagonal Zr with respect to longitudinal direction ranging from 0.20 to 0.35, the difference in Fl between the middle and the end being not more than the value calculated from (0.0935.times.Fl-0.00585) and an amount of bow at neutron irradiation of 35 GWd/t which bow occurs in the channel box for a reactor being not more than 2.16 mm.

Abstract: A non-aqueous secondary battery having a long life-time and a high capacity density is provided by increasing the discharging capacity of the negative electrode and extending the life-time of the negative electrode. The nonaqueous secondary battery has a positive electrode and a negative electrode reversibly absorbing and discharging an alkaline metal and a nonaqueous electrolyte, wherein the negative electrode is made of an inter-metallic compound containing at least one element selected from the group consisting of 4A group elements, P and Sb, the inter-metallic compound has any one of CaF.sub.2 type, ZnS type and AlLiSi type crystal structures, and the CaF.sub.2 type structure is any one an inverse-fluorite structure and a fluorite structure having a lattice constant larger than 6.36 .ANG..

Abstract: The lower end of each of a plurality of fuel rods is supported by a fuel supporting portion of a lower tie plate. The fuel supporting portion includes a plurality of second coolant paths for supplying a coolant from below the fuel supporting portion to a first coolant path defined above the fuel supporting portion and between the fuel rods. The total cross-sectional area of all the second coolant paths is smaller than the cross-sectional area of the first coolant path.

Abstract: The lower end of each of a plurality of fuel rods is supported by a fuel supporting portion of a lower tie plate. The fuel supporting portion includes a plurality of second coolant paths for supplying a coolant from below the fuel supporting portion to a first coolant path defined above the fuel supporting portion and between the fuel rods. The total cross-sectional area of all the second coolant paths is smaller than the cross-sectional area of the first coolant path.

Abstract: A fuel assembly avoiding the generation of irradiation damage, a Zr alloy used for the same, and a manufacturing method thereof. According to one embodiment, a super-saturated solid-solution Zr alloy powder having a crystal grain size in the range of 1000 nm or less and containing Fe, Ni and Cr is prepared by mechanical alloying, and the alloy powder is subjected to HIP, hot-working, cold-working and final heat-treatment.

Abstract: A fuel assembly comprises a plurality of fuel rods, tie plates for holding both ends of these fuel rods, and spacers which support these fuel rods. The spacer comprises a plurality of cells into which the fuel rods are inserted respectively, the adjacent cells being joined to each other at axial ends thereof, whereby a space between these cells being held or retained, and a plurality of loop springs held respectively on the cells. Each of the loop springs has a pair of resilient members which are located within the pair of adjacent cells and which urge the fuel rods in a radial direction, and a pair of connections which connect axial ends of the resilient members to each other. Each of the connections have a passage through which coolant flows axially and which is defined by a closed peripheral wall. The closed peripheral wall is not uniform in thickness. The pair of adjacent cells have at axial end portions of peripheral walls openings for accommodating or receiving the connections of the loop spring.

Abstract: A printing head provided in a wire-dot printer includes a plurality of first wire pins arranged in accordance with a predetermined rule, ends of the first wire pins facing a printing plane, a first driving mechanism for reciprocating the first wire pins in directions approximately perpendicular to the printing plane, a plurality of second wire pins longer than the first wire pins, ends of the second wire pins facing the printing plane, and a second driving mechanism for reciprocating the second wire pins in the same directions as the first wire pins, wherein the first and second driving mechanisms are arranged along a direction approximately perpendicular to the printing plane under a condition in which the first driving mechanism is positioned nearer the printing plane than the second driving mechanism.

Abstract: In a method of fabricating a channel box for use in a nuclear reactor, Zr-alloy sheet material is formed into a tubular channel box. The method includes solution heat treatment of the Zr-alloy sheet material including quenching from a temperature at which .beta.-phase is present. After the solution heat treatment, portions of the Zr-alloy sheet are thinned relative to other portions by a non-stressing thinning process, such as chemical etching in a bath. The corrosion resistance imparted by heat treatment is retained, and the heat treatment itself is easily performed on material of uniform thickness.

Abstract: A fuel assembly, where crystallographic orientations of a channel box are brought into a random distribution; and cladding tubes, spacers and a channel box are made from highly corrosion-resistant, Fe--Ni, zirconium-based alloy, hardened in the (.alpha.+.beta.) phase or .beta.-phase temperature region, has an average discharge burnup level of 50 to 550 GWd/t.

Abstract: A fuel assembly for a nuclear reactor comprising a fuel cladding tube of three-layer structure having an outer surface in contact with reactor water of the nuclear reactor, an inner surface layer in contact with the nuclear fuel, and an intermediate layer interposed between the outer surface layer and the inner surface layer. the outer surface layer is made of a Zr-based alloy containing Nb, Sn and Mo. The inner surface layer is made of pure zirconium. The intermediate layer is made of a high ductility alloy which is higher in ductility than the outer surface layer and is higher in strength than the inner surface layer.

Abstract: A zirconium based alloy plate of low irradiation growth, containing not more than 5 wt % Sn and/or not more 5 wt % Nb, and the balance Zr of not less than 90 wt %. The alloy plate has a texture that <0001> orientation (Fr value) with respect to direction perpendicular to the surface of the plate ranges from 0.20 to 0.50. This alloy plate is effective in being used to form a fuel channel box. Also a fuel assembly using this channel box is provided in which the crystal orientation of the zirconium alloy is made random by a heat treatment. Specifically, by the heat treatment, the Fr, Ft, and Fl values thereof are set to 0.25 to 0.50, 0.25 to 0.36, and 0.25 to 0.36, respectively.

Abstract: A plant operational status monitoring supervisory system comprising; means for extracting information directly relating to water quality of an objective portion consecutively for a period of time by means of an electrochemical water quality sensor installed in an objective portion to monitor in-situ in a plant; means for evaluating water quality based on thus extracted information; means for comparing an obtained water quality evaluation result with a reference value for a predetermined plant operation procedure; and means for displaying or storing necessary portion out of said comparison results; is disclosed.

Abstract: A channel box and/or a spacer of a fuel assembly is a welded construction and made of a Zr-Nb-Sn alloy comprising 0.5-2.2 wt % Nb, 0.5-1.5 wt % Sn contained so as to satisfy the relation of Sn(wt %) 22.times.Nb(wt %)--3.0, and balance Zr or a Zr-Nb-Sn-Mo alloy comprising 0.5-2.2 wt % Nb, 0.5-1.5 wt % Sn contained so as to satisfy the relation of Sn(wt %).gtoreq.2.times.Nb(wt %)--0.3, 0.1-0.8 wt % Mo, and balance Zr. The welded portion, its heat affected zone and the unwelded portion of the channel box and/or the spacer have substantially the whole equilibrium phase structure.

Abstract: A printer head is connected to its counterbalance by a counter drive in a manner to reduce shock and noise when the printer head is reciprocated by a linear motor. The counter drive comprises a pulley and a pair of belts or wires which are wound approximately half way around the pulley in respective opposite directions on opposite sides of the pulley, with one end of each belt being connected to the counterbalance, and the other end of each belt being connected to the printer head. Thus, the counterbalance moves in the opposite direction of the printer head. A movable element of the linear motor is connected coaxially to the counterbalance, in a manner such that the weight of the movable element is included in the total weight of the counterbalance. The printer head is mounted on a carriage which the carriage has a roller spaced laterally from the shaft. slides along a shaft.