416 results about "Magnetic response" patented technology

According to the displacement modulation and optical assistance-based SERF atom magnetometer magnetic imaging method, an SERF atom magnetometer integrated with a magnetic flux guider is used as a magnetic sensor, and low-frequency magnetic field modulation is introduced to the magnetic sensor by controlling a to-be-tested sample to perform periodic infinitesimal displacement in the sensitive direction of the magnetic sensor; the modulation signal is demodulated by combining a phase-locked amplification technology, and a magnetic response signal subjected to phase-locked demodulation at each spatial position is extracted; constructing a magnetic response matrix through two-dimensional track scanning of micron-order step pitch; an image acquisition module and a reflection optical assembly are introduced for spatial registration so as to monitor the relative position in real time, and the visibility and controllability of the magnetic imaging process are guaranteed; the point-by-point detection of fT-level weak magnetic signals can be realized on the premise that an array structure is not needed; the low-frequency noise interference can be effectively inhibited, the stability and definition of direct-current and low-frequency magnetic field imaging are improved, and the method is suitable for high-resolution space imaging application of weak magnetic sources such as magnetic domain structures, nervous tissue slices and ancient rock samples.

The invention provides a graphene-boron nitride composite epoxy resin material and a preparation method thereof, the surface of a graphene-boron nitride filler is modified to obtain a filler with magnetic response, the filler is added into epoxy resin, and the filler can be in more sufficient contact and ordered arrangement under the action of an external magnetic field, so that the graphene-boron nitride composite epoxy resin material is obtained. The heat conductivity coefficient of the composite material is effectively improved. Tests show that when the filler accounts for 25%, the heat conductivity coefficient reaches 2.1 (W / mk), and the friction coefficient can be effectively reduced and is reduced by about 30% compared with pure epoxy resin. The research of the invention provides a new thought and method for preparing the epoxy resin-based composite material with high heat-conducting property, expands a new field and direction for the application of epoxy resin in the field of electronic packaging, and has practical significance.

The invention provides a double-source magnetic field comprehensive detection and analysis method and system based on a buried metal pipeline, and the method comprises the following steps: applying composite magnetic field excitation to a target section of the pipeline, and synchronously collecting mixed magnetic response signals through a magnetic sensor array disposed along the axial direction of the pipeline. The mixed signal is separated into a slowly varying component representing quasi-static background stress and a burst component representing a pipeline stress event, and the burst component is extracted. And carrying out dispersion elimination inverse operation processing on the extracted burst component, and accurately determining the position information of the pipeline stress event on the pipeline through joint optimization solution by combining the time difference of arrival and the energy attenuation of the original waveform characteristics on different sensors. And inputting energy and position information of a pipeline stress event into the model, and continuously calculating and updating an accumulated damage factor of a specific position of the pipeline. According to the invention, the stress event of the buried metal pipeline can be accurately identified and positioned.

The invention discloses a shielding material evaluation method and system based on big data and a transient electromagnetic method, and relates to the technical field of shielding material evaluation, and the method comprises the steps: exciting a shielding material through a high-frequency pulse, obtaining electromagnetic parameters such as magnetic conductivity, dielectric constant, conductivity and shielding effectiveness, and carrying out the evaluation of the shielding material; and the transient electromagnetic response of the material is recorded by using a sensor array in different incident angles, polarization directions and frequency ranges, and an excitation signal is dynamically adjusted. An electromagnetic signal is decomposed by adopting an empirical mode, different frequency components are extracted, signal complexity is calculated through multi-scale entropy analysis, and an electromagnetic absorption mode is quantified. And optimizing a shielding effectiveness calculation model on the basis of electromagnetic wave transmittance in combination with time attenuation, multiple scattering and dynamic absorption characteristics, and finally optimizing shielding material parameters. The method has better effects in the aspects of calculation efficiency, adaptability and accuracy.

Microparticles for detecting biological materials are provided. Each of the microparticles includes: a core-shell structured microparticle consisting of a core including a magnetically responsive metal and a shell layer surrounding the core and having a uniform thickness; and capture probes introduced onto the shell layer to capture biological materials.

The invention discloses a preparation method of a programmable soft robot. The preparation method comprises the following steps: mixing magnetic particles, Ecoflex, PDMS and a curing agent according to a certain mass ratio, and stirring to obtain a magnetic response soft material; preparing a male mold and a female mold, assembling to form a preparation mold, and curing the magnetic response soft material in the preparation mold to obtain the soft robot; the solidified magnetic response material is magnetized and heated at the same time, and the programmable soft-bodied robot is obtained; and after cooling to the room temperature, opening the preparation mold, and taking out the programmable soft robot. The invention further discloses the programmable soft-bodied robot and a preparation mold of the programmable soft-bodied robot. The process is simple, the manufacturing cost is low, a programmable three-dimensional magnetic domain distribution structure is rapidly achieved through an in-situ heat-assisted magnetizing method, magnetic domain distribution is accurately controlled, the programmable soft robot has the multi-mode movement capacity and can execute transportation tasks in the liquid environment, and directional operation and accurate control are achieved.

The invention relates to the technical field of preparation of composite functional materials, in particular to a scale structure coating based on a PDMS / Co (at) SiO2 composite material and a preparation method and application of the scale structure coating. The preparation method comprises the following steps: mixing vinyl-terminated polydimethylsiloxane with methylhydrosiloxane to obtain a pre-polymerized solution; dispersing cobalt powder in the prepolymerization liquid to obtain a PDMS / Co mixture, coating the PDMS / Co mixture on the surface of a mold with a scale structure, and stripping the mold after curing to obtain a PDMS / Co scale array; and modifying SiO2 nanoparticles on the surface of the PDMS / Co scale array to obtain the scale structure coating based on the PDMS / Co coated SiO2 composite material. According to the invention, by constructing the multistage micro-nano structure and cooperating with the magnetic response and photothermal effect, a ''magnetostrictive unbalance-elastic rebound'' liquid drop directional transport mechanism and a photothermal-super-hydrophobic cooperative anti-icing function are constructed, and the problems of low energy efficiency, poor environmental adaptability and easy failure under extreme conditions of an existing anti-icing material are solved.

The invention relates to a light / heat / magnetic detachable high-strength polyurethane adhesive as well as a preparation method and application thereof. The light / heat / magnetic detachable high-strength polyurethane adhesive comprises a polyurethane adhesive and a functional filler. According to the light / heat / magnetic detachable high-strength polyurethane adhesive prepared by the preparation method disclosed by the invention, the colloid is black, and the adhesive has excellent light absorption performance and can realize rapid separation of an adhesive interface under infrared irradiation through a heat effect; meanwhile, the ferroferric oxide can be vibrated and heated under the action of an external magnetic field due to the magnetic response characteristic of the ferroferric oxide, so that fracture and separation of the adhesive layer are promoted. By means of the technology, efficient and reversible disassembly of parts bonded through the hot melt adhesive is achieved, possibility is provided for recycling and reusing of bonding materials and devices, and the problem that traditional polyurethane hot melt adhesive cannot be recycled is solved.

The invention provides a butt joint device based on electromagnetic connection and an underwater navigation device, and relates to the technical field of underwater vehicles, the butt joint device comprises a first butt joint assembly and a second butt joint assembly, the first butt joint assembly comprises a first nut and a magnetic driving part arranged on the first nut in a sleeving mode, the second butt joint assembly comprises a telescopic rod, a connecting rod, a second nut and a magnetic response part, one end of the connecting rod is connected with the telescopic end of the telescopic rod, the other end is in threaded connection with the second nut, and the magnetic response part sleeves the periphery of the second nut. The magnetic driving part is used for attracting the magnetic response part to preliminarily butt the first butt joint assembly and the second butt joint assembly, the fixed end of the telescopic rod is driven to rotate to drive the connecting rod to rotate, and the connecting rod rotates and moves in the axial direction of the second nut to be in threaded connection with the inner wall of the first nut so as to secondarily butt the first butt joint assembly and the second butt joint assembly. Radial and axial wandering is eliminated, the stability and anti-disturbance capability after butt joint are enhanced, and the overall operation quality and efficiency are improved.

The invention provides an on-line intelligent monitoring system based on a coil, and relates to the technical field of data processing, and the system is used for calculating the comprehensive coupling degree between coil magnetic field change and current response according to monitoring data, obtaining a magnetic response correlation value, constructing a distribution matrix of coil magnetic field distribution characteristics, obtaining a coil local coupling map, and obtaining a current response correlation value. The method comprises the following steps: calculating the influence degree of temperature change on magnetic flux energy offset, obtaining a temperature drift correction value, identifying the relative offset trend of electromagnetic response and energy compensation, obtaining a phase offset, calculating the response self-stabilization degree of a coil in long-term operation, obtaining a dynamic balance factor, and identifying the dynamic characteristics of the coil in electromagnetic, temperature and space response dimensions. And judging whether the coil is in a response instability state or a normal operation state to obtain monitoring state result data. The state of the coil is monitored by identifying coupling characteristics of electrical parameters and temperature of the coil.

The invention discloses a GIL electromagnetic property detection method and system based on field circuit-mechanical coupling, and the method comprises the steps: building an electromagnetic field-circuit-mechanical coupling mathematical model based on a circuit mathematical model through employing a stiffness matrix of a magnetic vector position, a stiffness matrix of a conductor eddy current, and a load matrix of a conductor conduction current; engineering sections are divided, a finite element two-dimensional simulation model is built, an equivalent external circuit is built, coupling connection is conducted through an external circuit port voltage matrix, and an electromagnetic property detection model of the GIL is obtained; performing iterative solution to obtain transient electromagnetic response of each engineering section, wherein the transient electromagnetic response comprises magnetic flux density, current density and node transient electromagnetic force; detecting whether electromagnetic response abnormity exists in the actual operation process of the GIL or not; and simulating the electromagnetic stress of the GIL component in the abnormal engineering section in the three-dimensional structure field by adopting harmonic response analysis, and checking the electromagnetic and mechanical characteristics of the GIL. According to the method, the electromagnetic characteristics of the GIL can be simulated more accurately, the applicability is wide, the operation speed is high, and guarantee is provided for GIL short-circuit fault monitoring and safe and stable operation.

The invention discloses an inorganic normal-temperature rapid-hardening coal-rock mass reinforcing and filling material, and relates to the technical field of mine reinforcement. The material comprises a liquid A and a liquid B, the liquid A is prepared from cement, fly ash, magnetic nano silicon dioxide, citric acid and a layered bimetal oxide-sodium hexametaphosphate compound; and the liquid B comprises water glass, superfine limestone and water. During use, the liquid A and the liquid B are mixed according to the volume ratio of 1: 1 and injected into a target area, and a 1.5 Tesla magnetic field is applied at the initial stage of grouting until the grout is initially set. Through the synergistic effect of the compound protection dispersing agent, the magnetic particles and an external magnetic field, the technical problems that an existing material is unstable in performance due to temperature change, nanoparticles are prone to agglomeration, and magnetic response is attenuated in an alkaline environment are effectively solved; the technical effects of rapid solidification, high strength and excellent durability in high-temperature, low-temperature and complex mine environments are achieved.