19 results about "Magnesium diboride" patented technology

The invention discloses a magnesium diboride superconducting wire and a preparation method thereof, and belongs to the technical field of superconducting wire processing. The preparation method comprises the following steps: preparing an MgB2 superconducting wire by adopting an in-situ powder sleeve method and a central Mg diffusion method, loading an Mg rod into a pre-pressed B tube to obtain an Mg / B composite rod, loading the Mg / B composite rod into an Nb / Cu composite tube, and loading MgB2 superconducting powder into a gap area between the Mg / B composite rod and the Nb / Cu composite tube to prepare the magnesium diboride superconducting wire. In the heat treatment process, the Mg element in the center area diffuses towards the surrounding B element and forms MgB2, meanwhile, the MgB2 powder on the edge serves as a template to induce and promote the solid-phase reaction of the Mg element and the B element, an MgB2 superconducting phase with the higher purity is generated, and therefore the wire rod obtains the higher current-carrying performance. The invention provides the MgB2 wire rod with better current-carrying performance under a low-field application condition.

The application relates to a high-conductivity and high-activity Ir@TiO2 anode catalyst, a preparation method and application thereof in a proton exchange membrane electrolytic cell, and belongs to the technical field of inorganic functional catalyst materials. The iridium source and the titanium source are mixed at room temperature, a reducing agent magnesium diboride is added, the mass ratio of the magnesium diboride and the iridium source is 2:1, the mass ratio of the titanium source and the iridium source is 1-100:1; then the mixture is placed in a high-temperature and high-pressure reaction kettle, and is reacted at 80-200 DEG C for 10 min-4 h, and the high-conductivity, high-activity and easily enlarged Ir@TiO2 anode catalyst is obtained after being reduced to room temperature. The obtained Ir@TiO2 anode catalyst is dispersed in a mixed solution of water and ethanol with a volume ratio of 1:1, is prepared into slurry, is prepared into a membrane electrode through a coating means, and is assembled in a PEM electrolytic cell, and when the iridium load is 0.5 mg / cm 2 , the high activity and stability are still maintained.

The present invention discloses a powder loading device and method for preparing magnesium diboride superconducting wire using a central Mg diffusion method. The method comprises preparing two matching semicircular stainless steel troughs and four copper tubes, and forming closed grooves in each of the two semicircular stainless steel troughs. A copper tube is sleeved and fixed at one end of the semicircular stainless steel trough. One end of a niobium foil is pressed against the copper tube and spread over the inner wall of the stainless steel trough, with the niobium foil being pressed against the inner wall of the stainless steel trough. Another copper tube is fixed to the niobium foil at the other end of the stainless steel trough. Boron powder is filled and continuously compacted to form two semicircular boron powder grooves wrapped with niobium foil. A magnesium rod is inserted into the center of the two matching copper tubes, and a semicircular groove for the magnesium rod is pressed into the center of the boron powder in the semicircular groove. The two semicircular boron powder columns wrapped with niobium foil and with magnesium rod grooves are combined and inserted into a barrier sleeve serving as a barrier layer. After drawing and rolling, a uniform and dense single-core wire is produced. The present invention facilitates optimization of the tube loading process and is more conducive to automated tube loading.

The present invention belongs to the technical field of superconducting wire materials, and discloses a magnesium diboride superconducting flat wire and a preparation method thereof. It includes: S1. Select a copper groove wire and a MgB2 round wire workpiece; S2. Tin-plate the copper groove wire, and then pass it through a U-shaped groove die to obtain a soft-state thin-walled copper groove wire; S3. Pass the soft-state thin-walled copper groove wire and the MgB2 round wire through a rectangular die at the same time for cold processing combination to obtain a nested structure MgB2 tin-plated flat wire; S4. Perform surface polishing and tin removal procedures on the nested structure MgB2 tin-plated flat wire, and only retain the tin-plated layer in the groove to obtain a MgB2 tin-removed flat wire; S5. Wind the MgB2 tin-removed flat wire on a steel wheel and place it in a heat treatment furnace for heat treatment to obtain a MgB2 superconducting flat wire. The present invention effectively solves the problems of poor bending resistance and poor mechanical properties of the MgB2 superconducting flat wire, and realizes that good current-carrying performance can still be maintained after repeated winding.

The invention discloses a preparation method of a doped magnesium diboride superconducting wire. The preparation method comprises the following steps: drilling a plurality of holes in a nickel-based alloy ingot; adding an organic adhesive into the boron powder, mixing and extruding to obtain a boron tube; putting a magnesium-aluminum alloy rod into the boron tube to obtain a multi-core magnesium diboride composite ingot; carrying out cold drawing treatment to obtain a multi-core magnesium diboride wire rod; and carrying out copper plating and heat treatment on the multi-core magnesium diboride wire rod to obtain the magnesium diboride superconducting wire rod. According to the invention, the nickel-based alloy is used as a metal matrix, so that the wire rod does not generate surface cracks in the whole processing process, and the wire rod can be directly stretched to the final specification without introducing annealing; in the phase forming process, carbon atom doping is introduced, the critical current density of the magnesium diboride superconducting wire in an irreversible field and a high field is effectively improved, a magnesium-aluminum alloy rod with low aluminum content is adopted as a center magnesium source, and the upper critical magnetic field of magnesium diboride is improved.

The present invention discloses a magnesium diboride superconducting wire and a preparation method thereof, belonging to the technical field of superconducting wire processing. The magnesium diboride superconducting wire is prepared by the in-situ powder-in-tube method and the central Mg diffusion method. A Mg rod is loaded into a pre-pressed B tube to obtain a Mg / B composite rod. The Mg / B composite rod is loaded into a Nb / Cu composite tube, and magnesium diboride superconducting powder is loaded into the gap region between the Mg / B composite rod and the Nb / Cu composite tube to prepare the magnesium diboride superconducting wire. During the heat treatment process, the Mg element in the central region diffuses towards the surrounding B element to form MgB2. At the same time, the MgB2 powder at the edge acts as a template to induce and promote the solid-phase reaction between the Mg element and the B element, generating a MgB2 superconducting phase with higher purity, so that the wire obtains higher current-carrying performance. The present invention provides a MgB2 wire with relatively excellent current-carrying performance under low-field application conditions.

A magnesiumdiboride (MgB2) powder-in-tube (PIT) wire has a cross-section showing —voids, —magnesiumdiboride, and —oxides, as measured by energy-dispersive X-ray spectroscopy. Oxides are located at the borders between the voids and the magnesiumdiboride. The MgB2 PIT wire has a higher degree of superconductivity.

The invention relates to the technical field of bone repair, in particular to a magnesium diboride nano-enzyme with an ROS quenching effect and application of the magnesium diboride nano-enzyme. The invention provides a nano material MgB2 which is high in dehydrogenase-like activity, good in biological safety and excellent in chemical stability. The compound not only can scavenge free radicals in vitro, but also can efficiently scavenge free radicals in cells at the cellular level, and oxidative stress injury is reduced. The advantages can be expanded to the fields of multi-bone repair and bone regeneration.

The invention discloses a starch-based magnesium diboride mixture, a preparation method and application thereof, starch-based magnesium diboride gel and application thereof, the starch-based magnesium diboride mixture comprises soluble starch and magnesium diboride (MgB2), and the mass ratio of the soluble starch to the magnesium diboride is 1: (0.005-0.020). The material is simple in component and can be applied to repairing of stomach wounds and skin wounds.

The invention discloses a superhard superconductive B-C-N superhard material and a preparation method thereof, and belongs to the technical field of superhard materials, the superhard material comprises a three-dimensional interpenetrating composite structure composed of a superhard skeleton and a superconductive phase filled in the pores of the superhard skeleton; the superhard framework comprises a matrix formed by nano-twin diamond and lamellar cubic boron nitride embedded in the matrix, and a B-C-N ternary gradient transition layer exists at the interface of the nano-twin diamond and the cubic boron nitride area; the superconducting phase is magnesium diboride; the Vickers hardness of the superhard material ranges from 75.2 GPa to 82.1 GPa, and the superconducting transition temperature of the superhard material ranges from 35.8 K to 37.1 K; the mechanical property of a superhard material and the functional property of a superconducting material are perfectly fused into a whole, a comprehensive solution capable of replacing a traditional single-function material is provided, and the core problems that in the prior art, functions and performance are difficult to consider, and the service reliability of the material in an extreme environment is insufficient are effectively solved.

The invention discloses a preparation method of a magnesium diboride superconducting wire. The preparation method comprises the following steps: dissolving B powder and Mg powder through an acid solution to obtain a B salt solution and an Mg salt solution; mixing the B salt solution and the Mg salt solution to obtain a mixed solution; atomizing the mixed solution through an ultrasonic atomization device; after argon and CxHy gas are added, mixed gas is blown into a heat treatment furnace, and precursor powder is obtained; carrying out phase heat treatment on the precursor powder, and then loading the precursor powder into an Nb / Cu composite tube to obtain a single-core rod; and the single-core rods are bundled and assembled into a Monel alloy tube to obtain a multi-core composite wire, and the multi-core composite wire is subjected to heat treatment to obtain the multi-core magnesium diboride superconducting wire. The MgB2-nCn powder is prepared by adopting a spray pyrolysis method, the proportion of element components is more uniform, and the C element is doped into the powder by adopting a gas phase in-situ method, so that the distribution of the C element in the powder is more uniform, and the C element forms a high-density pinning center, thereby improving the superconducting performance of the wire rod in a high field.

The flexible superconducting micro-coaxial cable is designed for use in quantum computing systems. The micro-coaxial cable includes an inner conductor made of a first superconductive material, surrounded by a dielectric layer. Circumferentially surrounding the dielectric layer is a braided outer conductor, made of a second superconductive material, providing more than 90% coverage. The first and second superconductive materials can be either type-I superconductors, such as Aluminum(Al), Lead(Pb), Titanium(Ti), Indium(In), and Tin(Sn), or type-II superconductors, including magnesium diboride(MgB2), niobium-titanium(NbTi), niobium-tin(Nb3Sn), and niobium-germanium(Nb3Ge).

The invention relates to the technical field of contact material coatings, and particularly discloses a contact material surface coating and a treatment method thereof. The surface plating layer is obtained through sintering chemical plating and electroplating and comprises the following steps that (S01) sintering chemical plating is conducted, specifically, an alloy bar is taken to be pretreated, slurry is sprayed through a spray gun, then heat treatment is conducted in the argon protective gas environment, and standing is conducted overnight at the room temperature to obtain a first plating layer; and (S02) electroplating: placing the alloy bar subjected to sintering chemical plating in an electrolytic tank as a cathode, taking a silver sheet as an anode, and electroplating in a plating solution to obtain a second plating layer. The treatment slurry is prepared by mixing the following raw materials in parts by mass: 50-75 parts of a mixed solvent, 10-15 parts of magnesium diboride micro powder, 0.5-1 part of sodium silicate and 0.01-0.02 part of graphene oxide. The surface coating of the prepared contact material has good self-lubrication performance, and the arc oxidation behavior of a copper-tungsten contact can be inhibited.

The invention discloses a preparation method of a magnesium diboride superconducting wire taking magnesium tetraboride as precursor powder. Magnesium tetraboride is synthesized through the thermal decomposition reaction of magnesium borohydride and boron powder, precious metal elements are doped in the magnesium tetraboride powder, a Mg rod is fixed to the center of an Nb tube on the basis of a center magnesium diffusion method, the space between the Mg rod and the Nb tube is filled with the precious metal-doped magnesium tetraboride powder, a single-core wire is prepared through cold machining, and after the two ends of the wire are flattened, the single-core wire is prepared into the high-strength magnesium alloy. And carrying out primary sintering in a tubular furnace to generate a magnesium diboride superconducting phase, bundling and stacking the primarily sintered wires, and carrying out secondary densification pressure sintering to obtain the magnesium diboride superconducting wire. The magnesium diboride superconducting wire prepared by the method is high in density and free of superconducting harmful phases, so that the magnesium diboride superconducting wire has good superconducting performance. The preparation method disclosed by the invention is simple, required equipment is relatively common, the cost is low, and the preparation method has very strong feasibility in the aspect of actual production and application.

The flexible superconducting micro-coaxial cable is designed for use in quantum computing systems. The micro-coaxial cable includes an inner conductor made of a first superconductive material, surrounded by a dielectric layer. Circumferentially surrounding the dielectric layer is a braided outer conductor, made of a second superconductive material, providing more than 90% coverage. The first and second superconductive materials can be either type-I superconductors, such as Aluminum(Al), Lead(Pb), Titanium(Ti), Indium(In), and Tin(Sn), or type-II superconductors, including magnesium diboride(MgB2), niobium-titanium(NbTi), niobium-tin(Nb3Sn), and niobium-germanium(Nb3Ge).

The present application relates to the technical field of contact material coating, and specifically discloses a contact material surface coating and a treatment method thereof. The surface coating is obtained by sintering chemical plating and electroplating, comprising the following steps: [S01] Sintering chemical plating: take the alloy rod for pretreatment, spray the treatment slurry with a spray gun, then perform heat treatment under an argon protective gas environment, and stand overnight at room temperature to obtain the first coating; [S02] Electroplating: place the alloy rod after sintering chemical plating in an electrolytic cell as a cathode, a silver sheet as an anode, and electroplate in a plating solution to obtain a second coating. The treatment slurry is prepared by mixing the following raw materials in parts by mass: 50-75 parts of a mixed solvent, 10-15 parts of magnesium diboride powder, 0.5-1 parts of sodium silicate, and 0.01-0.02 parts of graphene oxide. The surface coating of the contact material prepared in the present application has good self-lubricity and can inhibit the arc oxidation behavior of copper-tungsten contacts.

The flexible superconducting micro-coaxial cable is designed for use in quantum computing systems. The micro-coaxial cable includes an inner conductor made of a first superconductive material, surrounded by a dielectric layer. Circumferentially surrounding the dielectric layer is a braided outer conductor, made of a second superconductive material, providing more than 90% coverage. The first and second superconductive materials can be either type-I superconductors, such as Aluminum (Al), Lead (Pb), Titanium (Ti), Indium (In), and Tin (Sn), or type-II superconductors, including magnesium diboride (MgB2), niobium-titanium (NbTi), niobium-tin (Nb3Sn), and niobium-germanium (Nb3Ge).

The utility model relates to a magnetic resonance imaging system capable of being used for examination in a vertical load state, which is provided with an MRI magnet and / or an MRI main body, the MRI magnet and / or the MRI main body are / is vertically arranged, a vertical detection space is arranged in the MRI main body, the magnetic field of the detection space is a vertical magnetic field, the magnet of an MRI facility is made of magnesium diboride superconducting material, and the magnetic field of the MRI facility is made of magnesium diboride superconducting material. Solid nitrogen is used as a cooling medium, the phase change latent heat of the solid nitrogen is used for stabilizing the temperature under the condition of 35.6 K so as to facilitate vertical placement of the superconducting magnet, and the MRI main body is vertically and movably connected with the base through a lifting mechanism. The magnetic resonance imaging device is suitable for magnetic resonance imaging requirements in a vertical state.