58 results about "Magnetic nanowires" patented technology

The present invention belongs to the field of aluminum-base material in metallurgical technology, and is especially aluminum-base wave absorbing material and its preparation process. The present invention features that aluminum or aluminum alloy plate is treated first through one-step or two-step DC or AC anode oxidation process to form aluminum-base porous alumina template, or AAO template, with porous alumina film in the surface; and the template is then DC or pulse current electrochemically deposited to assemble nanometer magnetic metal wire array in the AAO porous film, so as to make the aluminum-base wave absorbing material with in-situ assembled nanometer magnetic metal wire array in the surface. The present invention has close combination between the wave absorbing material and the substrate and high wave absorbing effect caused by the coupling effect and the size effect of the nanometer wire array. The present invention may be used widely in stealth and electromagnetic shield.

In accordance with the invention, a surface is provided with a plurality of microscale magnets (“micromagnets”) disposed on a surface in a pattern to form a desired distribution of magnetic field strength. Cells and magnetic nanowires are attached, immersed in fluid, and flowed over the pattern. The nanowires and their bound cells are attracted to and bound to regions of the pattern as controlled by the geometry and magnetic properties of the pattern, the strength and direction of the fluid flow, and the strength and direction of an applied magnetic field.

The invention provides multisegmented, multifunctional magnetic nanowires for the probing and manipulation of molecules at the cellular and subcellular level. The different segments of the nanowire may have differing properties, including a variety of magnetic, non-magnetic, and luminescent behavior. Differences in surface chemistry allow different segments of a single nanowire to be functionalized with different multiple functional groups and / or ligands, giving the wire chemical multifunctionality.

This invention provides an optically transparent electrically conductive layer with a desirable combination of low electrical sheet resistance and good optical transparency. The conductive layer comprises a multiplicity of compound magnetic nanowires in a plane, the compound nanowires being aligned roughly (1) parallel to each other and (2) with the long axes of the compound nanowires in the plane of the layer, the compound nanowires further being configured to provide a plurality of continuous conductive pathways, and wherein the density of the multiplicity of compound magnetic nanowires allows for substantial optical transparency of the conductive layer. A compound magnetic nanowire may comprise a silver nanowire covered by a layer of magnetic metal such as nickel or cobalt. Furthermore, a compound magnetic nanowire may comprise a carbon nanotubes (CNT) attached to a magnetic metal nanowire. A method of forming the conductive layer on a substrate includes: depositing a multiplicity of compound magnetic conductive nanowires on the substrate and applying a magnetic field to form the compound nanowires into a plurality of conductive pathways parallel to the surface of the substrate.

The invention provides a magnetic field and application of magnetic nanowires in a transparent conductive film. The magnetic nanowires are arranged linearly in the transparent conductive film through the magnetic field. The magnetic nanowires are simple in process and are rapidly oriented to be arranged in columns under the effect of the magnetic field only. The invention also finds that through the combination of a microcosmic orderly magnetic nanowire layer and a transparent conductive nanolayer frequently used in the field, and under the circumstance that the quantity of a conductive material is not changed, the conductivity is improved greatly and the transmittance keeps unchanged.

A magnetic random number generator is disclosed. The magnetic random number generator comprises: a) a Hall cross structure comprising at least one magnetic nanowire with perpendicular magnetic anisotropy; b) an in-plane pulsed current generator operable to generate stochastic nucleation of domain walls (DWs) in the Hall cross structure; and c) a sensor configured to measure a parameter of the Hall cross structure upon DW nucleation, wherein said parameter has a value representing a random number. A greater number of Hall cross structures may be employed to generate a random number having a greater number of bits.

The invention relates to a preparing method for a Sm-Co / Fe-Co series biphase coupling magnetic nanowire array and relates to electrolysis production of metal powder of autolysis solutions. The Sm-Co / Fe-Co series biphase coupling magnetic nanowire array with a high deposition rate is obtained through a single-groove double-liquid direct-current chemical deposition method, annealing treatment is carried out on the biphase coupling magnetic nanowire array, and finally the Sm-Co / Fe-Co series biphase coupling magnetic nanowire array with high overall magentic performance is obtained. The defects that in the prior art, the requirement for the condition of preparing a Sm-Co / Fe-Co series biphase nanometer coupling material is high, and the deposition rate of a Sm-Co binary alloy nanowire is low are overcome.

This invention provides an optically transparent conductive layer with a desirable combination of low electrical sheet resistance and good optical transparency. The conductive layer comprises a multiplicity of magnetic nanowires in a plane, the nanowires being aligned roughly (1) parallel to each other and (2) with the long axes of the nanowires in the plane of the layer, the nanowires further being configured to provide a plurality of continuous conductive pathways, and wherein the density of the multiplicity of magnetic nanowires allows for substantial optical transparency of the conductive layer. Furthermore, the conductive layer can include an optically transparent continuous conductive film, wherein the multiplicity of magnetic nanowires are electrically connected to the continuous conductive film. A method of forming the conductive layer on a substrate includes: depositing a multiplicity of magnetic conductive nanowires on the substrate and applying a magnetic field to form the nanowires into a plurality of conductive pathways parallel to the surface of the substrate.

The invention provides a method for preparing a magnetic nanometer array and transferring the magnetic nanometer array to a metal substrate. The method includes the steps that a secondary anode oxidation method is utilized to prepare an aluminum oxide porous die plate which is not through, magnetic nano materials are deposited in holes of the die plate, the length of a deposited nanowire is controlled to make a certain unfilled depth reserved in the holes of the die plate, metal is deposited on the surface of the die plate, a continuous metal film with the nano holes is formed, thermocompression bonding is conducted on the continuous metal film and the metal substrate under certain temperature and pressure, and eventually the die plate is dissolved, and the goal of transferring the magnetic nanowire to the metal substrate is achieved. The method is simple in process and convenient to operate, compatible with the micro-electronic processing process, particularly, low-temperature bonding is achieved by the utilization of the nanoscale effect of a formed porous nanometer metal film layer, and the method has wide application prospect in the field of manufacturing of magnetic sensors based on a micro electro mechanical system.

The invention discloses a composite material and a preparation method thereof. The preparation method comprises the following steps: S1, preparing a metal ion solution with a concentration of 0.01 to 1 mol / L, adding a complexing agent and a nucleating agent, regulating a pH value to be 10.0 to 13.5 by virtue of an alkaline solution, and preparing a solution A, wherein the metal ions are magnetic metal ions or a mixture of magnetic metal ions and nonmagnetic metal ions; S2, preparing 0.1 to 3 mol / L of reducing agent solution with strong reducing property, regulating the pH value of the alkaline solution to be 10.0 to 13.5, and preparing a solution B; S3, sufficiently mixing the solution A and the solution B, reacting at 50 to 100 DEG C and under a magnetic field condition of 0.005 to 1T, , ending the reaction before the agglomeration phenomenon, and preparing a reaction stock solution containing magnetic nanowires or alloy nanowires; and S4, compounding the reaction stock solution prepared in step S3 and a polymer. The preparation method is simple in preparation process, and the prepared composite material has the characteristics of excellent performance and low cost.

The invention relates to the field of air purification, and discloses a magnetic electret fiber air purifying and filtering material and a preparation method. The preparation method comprises the following preparation processes: (1) preparing metal ion solutions of ferric salt, cobalt salt and nickel salt; (2) adding into a mixed solution of cyclohexane, n-amyl alcohol, cetyl trimethyl ammonium bromide and oxalic acid to form a microemulsion, and calcining to prepare magnetic nanowire powder; (3) adding the magnetic nanowire powder, inorganic electret nanoparticle titanium dioxide, silicon dioxide and a polar polymer into a solvent to prepare electrostatic spinning fluid; and (4) performing electrostatic spinning on a non-woven fabric to prepare the magnetic electret fiber air purifying and filtering material. The magnetic nanowire added in the prepared magnetic electret fiber material not only enhances the initial potential but also slows down the attenuation of surface potentials, amagnetic field enables the material to keep surface potential for a long time in damp air, the magnetic field decay is extremely slow, the capture capacity of the material to particulate matters is enhanced, and the service life of the material is prolonged.

The invention discloses a preparation method of a magnetic nanowire, and belongs to the field of nervous system repair and nano-structure preparation. The preparation method of a magnetic nanowire comprises the following steps: 1, synthesizing magnetic nanoparticles with ferroferric oxide cores and a silicon dioxide coating; 2, constructing a static magnetic field, and the direction of the static magnetic field can be regulated and controlled at any angle in a two-dimensional plane; and 3, dropping the magnetic nanoparticles monodispersion liquid containing the Matrigel matrigel onto a slide in the static magnetic field, assembling the magnetic nanoparticles through the static magnetic field to form the magnetic nanowire, and fixing the linear structure of the magnetic nanowire through the Matrigel matrigel.

The present invention provides a cell eradication method and a cell eradication principle for necrotizing a cell by agitating a cell using a physical turning force from the impression of an AC magnetic field, after preparing a magnetic nanowire having a dipole and introducing the magnetic nanowire into a cell. Therefore, the composition for inducing cell eradication of the present invention, when applied to a cell that is requested to be removed such as a cancer cell, can eradicate the cell by applying a physical impact through the rotation of the nanowire introduced inside the cell. Additionally, the heat generated from induced current from the magnetic field impression can add an effect of thermotherapy, and also, attaching a drug to the surface of the nanowire enhances the treatment effects.

The invention discloses a preparation method of a one-dimensional magnetic nanowire array with an ultrahigh axial remanence ratio. An alumina template with uniformly-distributed through holes is prepared by using a two-time anodic oxidation method, and then, direct-current electrodeposition is carried out to prepare the magnetic nanowire array. In the electrodeposition process, a layer of silver as a cathode is sputtered on one side of the alumina template, a metal to be plated is used as an anode and placed in a plating tank, and a metal salt solution to be plated, contained in the plating tank, is used as a plating solution. A set voltage is added between the cathode and the anode, the current in a circuit is controlled at a constant value, then electrodeposition is carried out, and the deposition time is set according to the length of a required nanowire, thus the nanowire array growing in a template hole is obtained. By using the method, the nanowire array with an ultrahigh axial remanence ratio can be prepared, and meanwhile, good controllability can be achieved in the deposition process.

The invention relate to a preparation method of an Nd-Fe-Co ternary alloy magnetic nanowire. The method comprises the following steps of (1) mixing NdC<13>.6H<2>O, FeC<12>.4H<2>O, CoC<12>.6H<2>O and deionized water to prepare a Nd<x>Fe<y>Co<z> deposition liquid; and (2) performing electrochemical deposition by employing a DC voltage-stabilization power supply under a DC voltage of 1.5-2V and by taking graphite as a positive electrode, an AAO template as a negative plate and the Nd-Fe-Co deposition liquid prepared in the previous step as an electrolyte, and finally obtaining the Nd-Fe-Co ternary alloy magnetic nanowire, wherein a deposition current is (0.5-20) mA, and deposition time is 1-2 hours. The nanowires are huge in quantity and high in deposition rate, and the nanowires are arrangedin parallel, are high in order, uniform in diameter and large in length-diameter ratio.

The invention synthesizes a nickel ferrite magnetic nanocomposite material by two steps. Firstly, an ordered mesoporous SBA-15 is adopted as a template, the mesoporous nickel ferrite magnetic nanowire is synthesized by a nanometer copy method, and then the ordered nickel ferrite magnetic nanocomposite material is synthesized by an impregnation method. The magnetic nanocomposite material has a significant exchange biasing field (HEB) and a large coercive force (Hc). According to the nickel ferrite magnetic nanocomposite material, depending on the exchange biasing effect of antiferromagnetic and ferrimagnetic interfaces, super paramagnetic phenomenon of the nanometer material can be well inhibited, and application of the nanometer material in the fields of magnetic recording and spin electronic devices is facilitated.

The invention discloses a nanowire vertical array based fluid viscosity detection device and a detection method. The detection device comprises a human-machine interaction apparatus, a detection processing circuit, an excitation coil containing detection probe, and a microchip made from a magnetic nanowire array. The detection probe is connected to the detection processing circuit and the human-machine interaction apparatus in order, the microchip is placed into a to-be-detected fluid, and the detection probe is used for providing an alternating magnetic field to the microchip right above the to-be-detected fluid and detecting the real-time vibration signal of the microchip. The detection device provided by the invention has the advantages of compact structure, small volume, convenient movement, viscosity detection with low sample consumption, high stability and reliability, and adopts the magnetic nanowire array, greatly improves the sensitivity and response speed, also has no need to additionally consider the influence of fluid conductivity, and can be widely used in the field of fluid viscosity measurement.

The invention relates to a method for preparing conical AAO by alternately carrying out multiple steps. Firstly, primary anodic oxidation is carried out on a packaged aluminum sheet in a phosphoric acid system, a primary oxidation layer is removed in a chromic acid and phosphoric acid mixed solution, then anodic oxidation is carried out on the aluminum sheet, chambering is carried out in a phosphoric acid solution, and the steps of anodic oxidation and phosphoric acid chambering are repeated. By utilizing the method, a conical AAO template with the surface pore diameter of 375nm, the bottom pore diameter of 100nm and the pore depths of 1.5 [mu]m and 3 [mu]m is prepared. The pore depth, the surface and bottom pore diameters and the pore diameter change smoothness of the conical AAO are adjusted by controlling the oxidation time, the chambering time and the oxidation times. The conical AAO prepared through the method is high in order degree, controllable in parameter, free of physical imprinting and low in preparation cost. The invention not only opens up the field for researching the magnetostatic interaction between magnetic nanowires of an array structure, but also has potential application in the preparation of photoelectric materials by utilizing the conical structure characteristic.

The present invention relates to a biomolecular measurement system (1), which enables to measure the intermolecular forces arising from the interaction between two biomolecules or the intramolecular forces within a single biomolecule by using an atomic force microscope (AFM). In the present invention, the cantilever (2) is moved only when the actuator (4) moves the magnetic nanowire (3) and thus moves the molecule attached to the end of the magnetic nanowire (3). Since the cantilever (2) is not moved, fluctuation and disturbance is not created in the liquid containing the biomolecules. Thus, the measurements are made more accurately and with higher resolution. Additionally, by means of the actuator (4), the biomolecules are enabled to be moved upon exertion of magnetic force at any coordinate on x, y and z axes on the nanowire (3), or exertion of torque on two axes.

The invention discloses a core-shell heterostructure magnetic nanowire as well as a preparation method and application thereof and belongs to the technical field of nanowire materials. The core-shell heterostructure magnetic nanowire takes an iron nanowire as a core and takes silver as a shell, is prepared by combining a magnetic field-assisted induction liquid phase reduction method and a layer-island growth mode, and has excellent electrical conductivity, oxidation resistance, corrosion resistance and wave-absorbing performance. A molar ratio of Fe to Ag in a ferromagnetic nanowire in the core-shell heterostructure magnetic nanowire is 1 to (0.3-1.1); the minimum reflection loss reaches -58.69dB, and the effective absorption bandwidth with the reflectivity being smaller than or equal to -10dB is 5.78-13.10GHz. The core-shell heterostructure magnetic nanowire has the advantages of mild conditions, simple equipment, good repeatability, short period and large-scale production, and has wide application prospects in the aspects of microwave absorption, electro-catalysis, flexible transparent conductive films and surface enhanced Raman spectroscopy.

The invention discloses an electrode loading with a composite oxide magnetic nanowire and a carbon nanotube and its preparation and an application. The preparation includes steps of (1), mixing hexadecyl trimethyl ammonium bromide, hexamethylene and n-amyl alcohol evenly; then adding oxalic acid solution; after mixing evenly, adding mixed solution containing transition metal ion and cobalt ion; continuously stirring under the room temperature to obtain microemulsion; (2), centrifugally removing impurities and drying in the air to obtain powder; forging in the air to obtain the transition metal / cobalt composite oxide magnetic nanowire; (3), dissolving the transition metal / cobalt composite oxide magnetic nanowire and sodium dodecyl benzene sulfonate in ethylene glycol; after dispersing evenly, immersing a sponge or carbon felt electrode; taking out the sponge or carbon felt electrode and drying; immersing again; repeating the operation for many times to obtain the electrode. The actual application effect is stable and efficient, the electrode loaded with metal oxide / carbon nanotube can be prepared, and the plasma of organic pollutant can be degraded.

The invention discloses a flexible carbon fiber composite electromagnetic shielding film and a preparation method thereof, and belongs to the technical field of electromagnetic shielding. The preparation method comprises the following steps: pretreating chopped carbon fibers in a strong acid solution, compounding the pretreated chopped carbon fibers with a magnetic metal ion salt, uniformly growing magnetic nanowires on the chopped carbon fibers by adopting a hydrothermal reaction and high-temperature heat treatment method, performing suction filtration to obtain a magnetic chopped carbon fiber membrane, packaging the fiber film with resin, and carrying out heat treatment to finally obtain the flexible carbon fiber composite electromagnetic shielding film. Compared with a traditional prepared electromagnetic shielding material, the prepared magnetic microporous carbon composite film has the advantages of being high in structural stability, good in flexibility, high in shielding effectiveness and the like, and is expected to be applied to the field of high-performance electromagnetic shielding.

The invention provides a low-insertion-loss self-biasing microstrip circulator based on magnetic nanowire arrays, and belongs to the field of microwave passive devices. The low-insertion-loss self-biasing microstrip circulator comprises a microstrip Y-junction matching wire, a hexagonal prism dielectric layer of which the center is provided with a cylinder through hole, a metal bottom electrode and a cylinder center junction. The low-insertion-loss self-biasing microstrip circulator is characterized in that the cylinder center junction comprises a top layer insulating layer and a bottom layer insulating layer, and at least two nanowire array layers which are arranged between the top layer insulating layer and the bottom layer insulating layer. An air layer is arranged between the adjacent nanowire array layers. Three magnetic nanowire array layers formed by deposition of porous alumina templates are adopted to act as the center junction of the circulator, and the layers are mutually separated by the air layers so that the objective of reducing the overall dielectric constant of the center junction is realized, and the circulator has low insertion loss and high degree of isolation in microwave frequency band X-band.

The invention discloses a method for measuring spin seebeck coefficients of a magnetic nanowire. The method comprises the following steps: placing the magnetic nanowire on a resistance heating platform, and respectively measuring to obtain temperature resistance coefficients of platinum electrodes Pt1 and Pt2; focusing femtosecond laser or picosecond laser on the surface of the platinum, Pt1 or Pt2 electrode, measuring the resistance of the platinum electrodes Pt1 and Pt2, calculating the temperature of the platinum electrodes Pt1 and Pt2 according to the measured temperature resistance coefficients of the platinum electrodes Pt1 and Pt2, and calculating the temperature difference delta T between the platinum electrodes Pt1 and Pt2; by changing the magnetic field applied to the magnetic nanowire, the potential of the magnetic moment of the magnetic film on the magnetic nanowire in an anti-parallel state (AP) and a parallel state (P) is measured, and the spin seebeck coefficient of the magnetic nanowire is calculated. The measurement means is simpler and faster, the generated temperature gradient is larger, other secondary effects are avoided, and measurement is more accurate.

The invention relates to a preparation method for reticular samarium-cobalt multilayer magnetic nanowires, which comprises the following steps: preparing a polycarbonate (PC) film template containing a 3D reticular structure channel by using a high-energy heavy ion beam, and preparing net (SmCo)1-xCux / Cu nanowires by using a pulse electrodeposition technology. The obtained nanowires are of a mutually connected reticular structure and can be directly used as a magnetic nano-device; and secondly, by introducing a non-magnetic nano-layer Cu, the demagnetization coupling interaction of samarium cobalt is enhanced, and the comprehensive magnetic performance of the samarium cobalt nanowires is improved.

The invention relates to a self-temperature-control magnetic nanowire and s preparation method thereof, and belongs to the technical field of tumor magnetic induction thermotherapy. In order to solvethe problems of low heat production rate and agglomeration of magnetic nanoparticles, the invention provides a preparation method of a self-temperature-control magnetic nanowire. The preparation method comprises the following steps: anodizing an aluminum foil to prepare an aluminum anodized micro-channel template, depositing zinc-cobalt-chromium ferrite hydroxide in the micro-channel template by using a chemical coprecipitation method, performing sintering to form a zinc-cobalt-chromium ferrite magnetic nanowire, and carrying out surface hydrophobization treatment on the magnetic nanowire. Theself-temperature-control magnetic nanowire prepared by the invention has the diameter of 5-45nm, the length of 5-30mu m and the Curie temperature point of 42-45 DEG C, is stable in chemical propertyand excellent in magnetic property, has the Curie point temperature meeting the magnetic hyperthermia requirement, has the advantages of high heat yield, low possibility of agglomeration, good performance consistency and good biocompatibility, and can be used for batch production of magnetic nano media and magnetic hot seeds for magnetic hyperthermia.

The present invention relates to a biomolecular measurement system (1), which enables to measure the intermolecular forces arising from the interaction between two biomolecules or the intramolecular forces within a single biomolecule by using an atomic force microscope (AFM). In the present invention, the cantilever (2) is moved only when the actuator (4) moves the magnetic nanowire (3) and thus moves the molecule attached to the end of the magnetic nanowire (3). Since the cantilever (2) is not moved, fluctuation and disturbance is not created in the liquid containing the biomolecules. Thus, the measurements are made more accurately and with higher resolution. Additionally, by means of the actuator (4), the biomolecules are enabled to be moved upon exertion of magnetic force at any coordinate on x, y and z axes on the nanowire (3), or exertion of torque on two axes.

The invention discloses a preparing method of a one-dimensional Co<x>Fe<3-x>O4 magnetic nano wire with a component gradient. The preparing method includes: separately putting FeCl3 powder and CoBr2 powder into a first heating zone of a tube furnace according to a mole ratio of 2:1, putting a substrate into a second heating zone with the FeCl3 powder being put between the CoBr2 powder and the substrate and the distance between the FeCl3 powder and the CoBr2 powder being 5-8 cm, adjusting the temperature of the first heating zone of the tube furnace to be 700-950 DEG C and the temperature of the second heating zone to be 800-1000 DEG C, feeding a carrier gas into the tube furnace, maintaining the temperature for 2-3 h, cooling the tube furnace to the room temperature and taking the substrate out, thus obtaining the one-dimensional Co<x>Fe<3-x>O4 magnetic nano wire with the component gradient with the x being 0.05-0.25. According to the preparing method, the one-dimensional Co<x>Fe<3-x>O4 magnetic nano wire with the component gradient and a large area is prepared under the combination of temperature control and the distance between the substrate and a source substance.