Hitachi, Ltd.

Hitachi Cable, Inc.

Hitachi Engineerings and Services Co I, Ltd.

Fumio Iida

Naofumi Tada

Ryukichi Takahashi

Mitsuyoshi Tsuchiya

Takaaki Suzuki

Hideo Tsukamoto

Toshiyuki Shiino

Hideki Tanaka

Michiya Okada

Takahiko Kato

Yasuhisa Aono

Hideyo Kodama

Naoki Maki

Masakiyo Izumiya

Teruhiro Takizawa

Shinzo Ikeda

Hiromitsu Seino

Yoshiji Hotta

Kazuo Kuroishi

Shuji Sakai

In NMR system, for preventing a temperature gradient which causes a decrease in S/N ratio from being created in a sample area while suppressing deterioration in homogeneity of a magnetic field, a thermal conductor having high thermal conductivity is disposed in a room-temperature shim coil. The thermal conductor is provided as a coil bobbin, the temperature of the thermal conductor being controlled by a temperature controller using a heat exchanger. Temperature control gas, which is adjusted to a temperature equal to that of the room-temperature shim coil, is fed from the downside of a sample tube, and it is possible to suppress a temperature gradient from being created in a sample area. According to the present invention, since the temperature distribution can be made to be uniform so as to avoid creating a temperature gradient in the sample area while suppressing deterioration of homogeneity in the magnetic field, the NMR spectrum is sharpened so as to improve the S/N ratio.

NMR system

An object of the present invention is to solve the bending of an NMR probe and a room temperature shim coil so that they can be positioned easily. In the NMR spectrometer including split-pair magnets and a cross bore, a high rigidity straight pipe to which an NMR probe and a room temperature shim coil are attached so as to make an integral object, is provided. The outer diameter of the straight pipe is smaller than the inner diameter of a horizontal bore into which the room temperature shim coil and the probe are inserted. After the room temperature shim coil and the NMR probe are attached to the straight pipe by bolts, respectively, the integral object is inserted into the horizontal bore (a room temperature space) of the NMR spectrometer. The room temperature shim coil and the probe may be attached to different straight pipes.

NMR spectrometer

In an NMR apparatus provided with a split type magnet, in order to position a probe at a high precision in a narrow homogeneous magnetic field space, a positioning of a center of a probe coil is first located to a proper position by inserting an NMR probe from a horizontal bore. At this position, a sample tube is inserted from a vertical bore, and an NMR signal is measured from the probe coil. An NMR signal measuring apparatus amplifies the NMR signal from the probe coil, and executes an A/D conversion so as to determine an NMR spectrum signal, and an NMR signal analyzing apparatus compares the NMR spectrum signal. A probe is set at a position where a sharpness of the spectrum is largest, that is, a magnetic field homogeneity coefficient is high, by repeating the operations mentioned above.

NMR system and probe positioning method

A superconducting wire saved in weight and enhanced in mechanical properties is provided without damaging electric and thermal characteristics as an Al stabilizer, and further a method for producing the same, a high strength Al sintered alloy and powders used for the process are provided. A superconducting wire comprising an Al alloy of a high purity Al in which a small amount of ceramic ultrafine particles are dispersed and superconducting filaments embedded in the Al alloy, in which a large number of the ceramic ultrafine particles are dispersed in the area of 1 .mu.m.sup.2, and the areas of 1 .mu.m.sup.2 in which a large number of the ceramic ultrafine particles are dispersed, are formed over nearly the whole of the alloy.

Superconducting wire and composite superconductor

Object of the present invention is to obtain a Nb.sub.3 Al group superconductor having a high critical current density under a whole range of magnetic field from low to high such as 20 T level, manufacturing methods thereof, a Nb.sub.3 Al group superconducting precursory composition, and a magnet for high magnetic field. In a process for manufacturing Nb.sub.3 Al phase by a diffusion reaction of Nb.sub.2 Al phase and Nb phase, a part of the Nb.sub.2 Al phase is remained and dispersed in the Nb.sub.3 Al phase homogeneously as for magnetic flux pinning centers for a high magnetic field. As for a method for dispersing the Nb.sub.2 Al phase homogeneously, a Nb.sub.3 Al group superconducting precursory composition obtained by dispersing Nb particles and Nb.sub.2 Al ultrafine particles by a mechanical alloying method is used, and further, by a conventional method for generating Nb.sub.3 Al phase by a diffusion reaction of Nb and an aluminum alloy, the object of the present invention can be achieved. In accordance with the present invention, a high magnetic field such as 20 T level which has never been achieved with only superconductor at 4.2K can be generated economically with a more compact apparatus than ever, and a coil for generating a high magnetic field can be manufactured with only the Nb.sub.3 Al group superconductor. Therefore, the present invention is significantly effective for a nuclear fusion apparatus of a magnetic confinement type.

Nb.sub.3 Al Group superconductor containing ultrafine Nb.sub.2 Al

In a method for manufacturing Nb.sub.3 Al phase by a diffusion reaction of Nb.sub.2 Al phase and Nb phase, a part of the Nb.sub.2 Al phase is remained and dispersed in the Nb.sub.3 Al phase homogeneously as for magnetic flux pinning centers for a high magnetic field. As for a method for dispersing the Nb.sub.2 Al phase homogeneously, a Nb.sub.3 Al group superconducting precursory composition obtained by dispersing Nb particles and Nb.sub.2 Al ultrafine particles by a mechanical alloying method is used, and further, by a conventional method for generating Nb.sub.3 Al phase by a diffusion reaction of Nb and an aluminum alloy, A Nb.sub.3 Al group superconductor can be achieved.

Method for manufacturing Nb.sub.3 Al group superconductor

A tightly wound superconducting coil device includes a cooling medium vessel, a coil winding disposed in the cooling medium vessel, the coil winding including an unspliced superconducting wire and having a configuration such that a cooling medium disposed in the cooling medium vessel does not contact the unspliced superconducting wire, and an insulating member disposed between the coil winding and the cooling medium vessel, wherein a portion of the unspliced superconducting wire forming outer portions of the coil winding on two opposite sides of the coil winding has a composition which causes a stability margin of the outer portions of the coil winding to be greater than a stability margin of a remaining portion of the coil winding.

Unspliced superconducting coil device with high stability

A track vehicle such as a Maglev train has a body with superconducting coils mounted thereon which superconducting coils interact with vertically extending coils on guideways of a track to generate a propulsive force. The vehicle runs on wheels at low speeds but at higher speeds the superconducting coils may interact with ground coils to generate a lifting force. In order to reduce or eliminate stresses between the superconducting coils and the vehicle body, the vehicle has one or more wings of airfoil shape which generate lift. That lift may be sufficient to support the whole of the weight of the vehicle, enabling the ground coils to be eliminated. Furthermore, the shape of the superconducting coils may be changed so that they supply more energy to propulsive effects. Preferably the angle of incidence of the wing(s) is variable, to permit the lift generated thereby to be varied. This variation in the angle of incidence may be controlled by a sensor detecting the height of the body above the track, to maintain that height constant.

Track system and vehicle having both magnetic and aerodynamic

Disclosed is a superconductor which has an aluminum area at the center of the cross section of the superconductor and a copper-covered multifilamentary NbTi composite conductor at the periphery parts of the cross section formed around the aluminum area, wherein the cross-sectional area ratio of (Cu+Al)/NbTi is in the range of 0.5 to 3.0 and the cross-sectional area ratio of Al/Cu is in the range of 0.05 to 0.5.. The superconductor is provided by a method comprising a first step of providing a superconductor-copper composite hollow body in which copper films are applied around the superconductors, a second step of area reducing the composite hollow body, a third step of heat treating the body, a fourth step of inserting an aluminum body into the hollow of the hollow body, a fifth step of subjecting the body to working such as drawing, a sixth step of subjecting the body to working such as twisting, forming or the like, with an additional area reduction being carried out, if necessary, subsequent to the third step. A superconducting coil is made using the superconductor, and the coil is used for a magnetically levitated vehicle or a nuclear magnetic resonance apparatus.

Aluminum-stabilized superconductor and superconducting coil, and method

In a superconducting magnet apparatus including one winding of coiled superconductor wire, another winding of coiled superconductor wire, a cooling device for supplying coolant to cooling vessels which contain the respective windings therein and a non-magnetic partition wall interposed between the cooling vessels containing the respective windings to airtightly separate them, with these windings being located at relative positions enabling mutual inductance therebetween, even if quenching occurs in the superconducting magnet apparatus. It is designed to not lose the magnetic repulsive force such that equipment traveling at high speed can be safely transferred at least to the nearest station. In addition, electromagnetic levitation traveling equipment on which the above-described apparatus is installed and a control method therefore is also described.

Superconducting magnet apparatus, cooling system therefor, and

A superconducting magnetic levitated train and train system which includes a plurality of cars connected to each other, a group of superconducting magnets attached to the cars and a coil provided on the ground so that the superconducting magnetic levitated train is levitated by the magnetically induced repulsion between the superconducting magnets and the coil on the ground. The invention is characterized in that the superconducting magnet on a specified car has a predetermined stability margin which is larger than the stability margin of a superconducting magnet on the other cars. A method of controlling the superconducting magnetic levitated train which includes detecting a driven state of a superconducting magnet on a specified car and varying and controlling the travelling conditions for the train so that the stability margin of the superconducting magnet on the specific car is changed in accordance with the command from a train control. A superconducting coil for the superconducting magnetic levitated train includes a coil of a composite superconducting wire composed of multifilmentary NbTi wire having a low copper ratio. The outer surface thereof is coated with thin high-purity aluminum or the wire accommodates high-purity aluminum at the central portion of the cross section thereof.

Superconducting magnetic levitated train, train system method of

The present invention provides an intermetallic compound-based, composite superconductor suitable for use in superconducting coils for a high magnetic field, where the superconductive part is formed by thermal diffusion reaction, and which has such a structure that a metal layer of high melting point and high resistance is provided at the outermost periphery of a strand comprising a plurality of filaments containing a superconductive compound formed by diffusion reaction with the surrounding matrix, a stabilizer surrounding the matrix, and a diffusion barrier provided between the stabilizer and the matrix for preventing diffusion of superconductive compound-forming element in the matrix from diffusion into the stabilizer during the diffusion reaction, and the coupling current induced between the intermetallic compound-based superconductive wire members can be reduced by the provision of the metal layer of high melting point and high resistance. Furthermore, the superconductive parts can be formed by heat treatment, and the AC loss can be reduced thereby.

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Hitachi, Japan

Fumio Iida