32 results about "Superconducting critical temperature" patented technology

The present invention relates to a superconducting nanowire single photon detector comprising a superconducting nanowire configured and arranged for incidence of photons on a region of the superconducting nanowire and for forming a local non-superconducting region or hot spot on the region. The superconducting nanowire is made of a high Tc cuprate superconductor material having a superconducting critical temperature above 77K. The invention also relates to a method of obtaining a superconducting nanowire single photon detector of the invention.

The invention discloses a preparation method of a rare earth barium copper oxygen high-temperature superconducting film. The preparation method comprises the following steps: a) weighing rare earth metal salt, barium salt, copper salt and a doping element compound according to a ratio, and dispersing the earth metal salt, the barium salt, the copper salt and the doping element compound into a solvent to obtain a precursor, wherein the doping element compound can generate doping element oxide at 300 to 650 DEG C and under the oxygen atmosphere; b) coating the precursor on a substrate to form a precursor film; c) placing the precursor film into a heat treatment furnace, introducing oxygen, heating the furnace to 300 to 650 DEG C, preserving heat for 0 to 5 hours, and introducing water vapor when the furnace temperature reaches 80 to 120 DEG C until thermal decomposition is finished; d) introducing oxygen nitrogen mixed gas and water vapor, heating the furnace to 700 to 825 DEC C, preserving heat for 20 to 250 DEG C, and stopping introducing the water vapor at the last 1 to 30 percent of time of heat preservation; and e) cooling the furnace to 400 to 500 DEG C and preserving heat for 0 to 240 minutes to obtain a product. According to the rare earth barium copper oxygen high-temperature superconducting film obtained by the preparation method, the thickness is more than 300 nm, the superconduction critical temperature is more than 90 K, and the critical current density at the temperature of 77 K and under the self-field condition is more than 1 mA / cm<2>.

Magnetic field attenuation in a persistent current mode operation is prevented, heat generation at a connecting part between the persistent current switch and the superconducting coil, and increase in a cooling temperature of the superconducting coil in a current supplying mode is suppressed to a minimum. The refrigerator cooling-type superconducting magnet J according to the present invention including a superconducting coil (2), a persistent current switch (1) for switch between a persistent current mode and a current supplying mode; a superconducting coil (2), first and second cryogenic refrigerators (3, 4) for respectively cooing the superconducting coil (2) and the persistent current switch (1); a vacuum vessel (10) for housing the super conducting coil (2), the persistent current switch (1), and cooling stages (31, 32, 41, 42) of the first and second cryogenic refrigerators (3, 4), the magnet includes a superconducting wire (5) for connecting the superconducting coil (2) to the persistent current switch (1) and a superconducting bypass line (6) electrically connected in parallel to the superconducting wire along a longitudinal direction, wherein a superconducting critical temperature of the superconducting bypass line (6) is higher than a superconducting critical temperature of the persistent current switch (5).

The invention provides Nb nanobelt / martensitic NiTi memory alloy matrix composite filament and a production method thereof. The Nb nanobelt / martensitic NiTi memory alloy matrix composite filament comprises the following components: 7-15% (atomic percent) of Nb, Ti and Ni with the atom ratio of (0.8-1.2):1, wherein the sum of atomic percents of Ti, Ni and Nb is 100%. The Nb nanobelt / martensitic NiTi memory alloy matrix composite filament is prepared by carrying out the following steps: selecting simple substances nickel, titanium and niobium with purity of more than 99wt%; smelting and casting, so that ingot casting is obtained; homogenizing and annealing the ingot casting; and then carrying out hot forging and moulding; carrying out plastic processing, annealing treatment, at least once uniaxial drawing-loading-unloading circular deformation treatment on a profile subjected to hot forging, wherein deformation is 1-9%, so that the Nb nanobelt / martensitic NiTi memory alloy matrix composite filament is obtained. The Nb nanobelt / martensitic NiTi memory alloy matrix composite filament can reserve great tensile elastic strain of Nb nanobelt in a free-state composite material, superconduction critical temperature of the free-state composite material is increased, and a magnetic field of the free-state composite material is enhanced.

The invention relates to a high temperature superconducting material of gadolinium, thorium, oxygen, iron and arsenic, pertains to a ZrCuSiAs-type structure and has the same crystal structure as LaO1-yFyFeAs. The general formula of the high temperature superconducting material of gadolinium, thorium, oxygen, iron and arsenic of the invention is Gd1-xThx OFeAs, wherein, x is more than or equal to 0.05 and less than or equal to 0.30; the mole ratio of all elements content in the high temperature superconducting material gadolinium, thorium, oxygen, iron and arsenic is that Gd:Th: O: Fe: As is equal to 0.70 to 0.95: 0.3 to 0.05:1: 1: 1. According to the content of every element, the raw materials are mixed, ground, preformed, calcinated and quickly cooled, etc. so as to obtain a superconducting polycrystalline block. The high temperature superconducting material of gadolinium, thorium, oxygen, iron and arsenic of the invention has max superconducting critical temperature Tc which reaches56.5 K, estimated upper critical field Bc2 exceeding 100 Tesla, is superior to the LaO1-yFyFeAs superconductor with similar structure and has obvious advantages in practical use.

The invention provides a device for cooling a superconducting cable. The device comprises a superconducting energy pipeline, a base station cooler, a heat exchanger, an LNG immersed pump and a modulation device. A part of LNG in the superconducting energy pipeline is conveyed into the base station cooler to directly exchange heat with a power transmission terminal, so that the temperature of the power transmission terminal is maintained below the superconducting critical temperature; the temperature of the LNG subjected to heat exchange with the power transmission terminal rises to generate agas-liquid two-phase flow, and the gas-liquid two-phase flow enters the modulation device to be modulated into liquid and then, enters the LNG immersed pump; the LNG immersed pump conveys LNG to the heat exchanger for heat exchange; the heat exchanger reduces the temperature of the modulated LNG to be lower than the superconducting critical temperature; and then, the cooled LNG enters another power transmission terminal in the base station cooler for heat exchange; and the heat-exchanged LNG enters the superconducting energy pipeline, and the freezing point is reduced. According to the devicefor cooling the superconducting cable, LNG cold energy is fully utilized to make the temperature of the power transmission terminal maintained under the superconducting critical temperature, so that superconducting operation of the power transmission terminal is achieved.