摘要:
A method of producing a composite material of and Nb or V used for a superconductive wire comprises vacuum - melting two kinds of raw materials, 70 wt % Cu and 30 wt % Nb or V to form a melt; scattering the melt by a rotating disc to form a plurality of fine droplets each of which includes Cu and Nb or V at substantially the same compounding rate as the raw materials; and cooling rapidly the fine droplets by spraying an inert gas onto the scattering droplets thereby providing particulate bodies each of which dendrites of Nb or V are precipitated in Cu. The fine particles are compression - molded to form a molded product. The molded product is sintered to form an ingot in which the dendrites of Nb or V are dispersed homogeneously in the Cu base. The ingot is used for producing a superconductive wire, namely, it is subjected to cold rolling to reduce its sectional area, coating with Su or Ga, and diffusion heat-treating the wire to form Nb.sub.3 Sn or V.sub.3 Ga in the Cu base, whereby a superconductive wire is provided in which Nb.sub.3 Sn or V.sub.3 Ga are homogeneously dispersed in the Cu base.
摘要:
In a superconducting switching device including a switching member comprising a superconducting wire, and a magnetic field generation section for controlling superconducting-normal conducting transition caused in the switching member, the switching member comprises an oxide superconductor having a high critical temperature and having a large electric resistivity value under the normal conductive state.
摘要:
A superconductive magnet device comprising a coil assembly having a plurality of coil sections stacked along a center axis of the coil assembly, each of the coil sections being formed by winding a composite superconductive wire, which exhibits different superconductivities in one direction to another direction perpendicular to the one direction in a cross section of the wire, in layers in a direction perpendicular to the center axis, wherein the critical current density in a direction parallel to the center axis in the innermost layer of at least a central one of the coil sections is larger than the critical current density in a circumferential direction of the coil assembly. The present superconductive magnet device can withstand quenching of the superconductive state at a higher magnetic field than conventional ones.
摘要:
An aluminum-stabilized superconducting wire comprises an aluminum member, a copper member, and a first diffusion barrier layer formed between the aluminum member and the copper member. The copper member contains a plurality of bundles each having a multiplicity of fine filaments of Nb.sub.3 Sn embedded in a copper alloy and a second diffusion barrier layer surrounding the copper alloy. Preferably, the ratio m in the cross-sectional areas between the first diffusion barrier layer and the aluminum member is selected to meet the condition of 0.03.ltoreq.m
摘要:
In a nuclear magnetic resonance spectrometer, the shape of a detection coil is changed from a conventional cage type to a solenoid type of higher sensitivity. Accordingly, differing from the conventional superconductive magnet of multilayer air core solenoids, a superconductive magnet is right and left divided to split magnets for generating 11 T, preferably, 14.1 T in the horizontal direction, and the magnetic field uniformity is set to 0.001 ppm or less and the temporal stability is set to 0.001 ppm or less.
摘要:
Superconducting magnet system using a liquid helium for its operation and a permanent current switch and a system thereof applied to the superconducting magnet system employing a permanent current loop created by a superconducting material developing superconductivity when cooled. The system includes a superconducting magnet dipped in the liquid helium, the permanent current switch for driving or interrupting the superconducting magnet, and a cryostat for accommodating the superconducting magnet and the permanent current switch, and the permanent current switch is arranged over a liquid surface of the liquid helium.
摘要:
A magnetic field generator has a superconductive coil immersed in a coolant material. When power is supplied to the superconductive coil from a suitable power source, the superconductive coil is energized to generate the magnetic field. The ends of the superconductive coil may then be shorted through a persistent current switch, to maintain the magnetic field without the need for further power. The persistent current switch has a superconductive connection connected across the ends of the superconductive coil and a heater. These components are enclosed in a casing with a gap between these components and the casing. Apertures in the casing permit coolant material to enter the gap. When the heater is energized, it heats the coolant material in the gap until it vaporizes. There is then a significant decrease in the thermal conductivity through the gap and hence the superconductive connection is heated rapidly to its critical temperature. Only low power is needed. When the heater stops being energized, liquid coolant material fills the gap thereby rapidly cooling the superconductive connector to below its critical temperature.
摘要:
A magnetic recording apparatus with a magnetic head, superconductive layers formed over at least flux generating surfaces of the magnetic head and normal conductive regions of small size for passing the flux provided in the superconductive layers, over the flux generating surfaces, so as not to form a closed magnetic circuit so as to enable reversible spontaneous magnetization in a magnetic recording medium proximate thereto. The minimum unit size (recording wavelength) of the reversible spontaneous magnetization in magnetic recording of the magnetic recording medium can be reduced from the order of 1 .mu.m to that of 0.1 .mu.m. Thus it is possible to increase the surface recording density of the magnetic recording medium utilizing more than 100 Mb/in.sup.2, comparable to the density achieved by the opto-magnetic recording. This in turn makes it possible to provide a large disc apparatus having a capacity of 60 MB or more.
摘要:
In a nuclear magnetic resonance spectrometer, the shape of a detection coil is changed from a conventional cage type to a solenoid type of higher sensitivity. Accordingly, differing from the conventional superconductive magnet of multilayer air core solenoids, a superconductive magnet is right and left divided to split magnets for generating 11 T, preferably, 14.1 T in the horizontal direction, and the magnetic field uniformity is set to 0.001 ppm or less and the temporal stability is set to 0.001 ppm or less.
摘要:
In a nuclear magnetic resonance spectrometer, the shape of a detection coil is changed from a conventional cage type to a solenoid type of higher sensitivity. Accordingly, differing from the conventional superconductive magnet of multilayer air core solenoids, a superconductive magnet is right and left divided to split magnets for generating 11 T, preferably, 14.1 T in the horizontal direction, and the magnetic field uniformity is set to 0.001 ppm or less and the temporal stability is set to 0.001 ppm or less.