171results about "Magnetisation measurements" patented technology

Apparatus for determining magnetic properties of materials comprises a portable probe (1), an equipment trolley (2) holding cryogenics and electronics and connecting cables (3). The probe (1) comprises a drive coil (4) and a correction coil (5), the drive coil (4) being disposed symmetrically with respect to an inner second-order gradiometer sensor coil (8). Electrical connectors in the form of 2-metre long Belden (1192A) microphone cables (3) are used to connect the apparatus on the equipment trolley (2) to the drive coil (4), the correction coil (5) and the sensor coil (8). The drive coil (4) is driven so as to generate a sinusoidally varying magnetic field. The electronics comprise a flux-locked loop (9), a SQUID controller (10), a data acquisition module (11), which captures and processes the signals and a computer (12). A liquid-nitrogen dewar (13) is supported on the equipment trolley (2) and houses a sensitive SQUID detector (14) and a transfer coil (15) made from copper. Possible applications of the apparatus include an intra-operative tool for sentinel lymph node detection in the treatment of breast cancer, and a non-destructive evaluation tool for detecting voids and defects in aluminium and applications in the aeronautics industry.

Apparatus, method, and computer-accessible medium embodiments for a noninvasive mapping of electrical properties of tissues or materials. For example, it is possible to apply a plurality of stimulations to a target. It is possible to receive at least one signal from the target in response to the applied stimulations. Further, it is possible to process the at least one signal to determine electromagnetic-field-related quantities associated with the stimulations and the target response. Also, it is possible to supply the electromagnetic-field-related quantities to a system of equations relating these quantities to a plurality of electrical property values and residual field-related unknown values of the at least one target. It is also possible to determine a solution to the system of equations, including determining at least one electrical property of the at least one target.

The invention discloses a device used for material ferromagnetism and magnetization performance detection. The device comprises a laser device, linearly polarized light beams, a Glan-Thompson polarizer, an electromagnetic shielding cover, a radio frequency shielding box, a magnetic shielding cylinder, an axial scanning field coil, a heating and heat preservation module, atomic vapor bubbles, a light amplification detection module, a conveying tube sealing block, a conveying tube, a solenoid coil, a positioning frame and a grooved loading warehouse. The invention also discloses a method used for material ferromagnetism and magnetization performance detection. The device is integrated in structure and convenient to operate, material ferromagnetism and magnetization performance detection is acquired through nonlinear magneto-optical resonance dispersion signals, and the device has the characteristic of ultrahigh-sensitivity magnetic measurement and practical value in material selection of atomic frequency standards, atomic magnetometers and laser detection magnetic resonance instruments.

A calculation apparatus comprising: an acquiring unit to acquire an azimuth and an ellipticity angle of a polarization plane of a laser beam passing through a plasma; and a calculation unit to calculate at least one of a magnetic field profile, an electron density profile and an electron temperature profile in the plasma on the basis of the azimuth and the ellipticity angle.

The invention relates to a method for quickly measuring magnetic characteristics of magnetic materials. The method includes providing a to-be-measured magnetic core with closed magnetic circuits, respectively winding excitation windings and detection windings on the to-be-measured magnetic core and serially connecting the excitation windings, capacitors and resistors with one another to form a closed circuit; electrifying the excitation windings with direct currents, applying direct-current voltages on the capacitors, enabling the to-be-measured magnetic core with the closed magnetic circuits, the capacitors and the resistors to meet damped oscillation circuit conditions and measuring current change procedures of the excitation windings and voltage change procedures of the detection windings to obtain direct-current magnetic flux density corresponding to direct-current magnetic field intensity of the magnetic core under direct-current conditions, a cluster of alternating-current magnetic hysteresis loops under different magnetic flux density conditions and magnetic core loss under the different magnetic flux density conditions. The method for quickly measuring the magnetic characteristics of the magnetic materials has the advantages of short measurement periods and easiness in acquiring magnetic characteristic curves during deep saturation.

Apparatus for detection and measurement of agglutinations of magnetic particles employing Hall sensors (15, 16). A low frequency AC signal (24) is employed to excite or bias the Hall sensors which reside in a DC magnetic field (23). The particles are moved into operative relationship with the Hall sensors in order to generate a signal representing the number of particles on the substrate (22). The method for such detection and measurement is also part of the invention.

A magnetic inspection station for tubular members and methods for operating the same have a longitudinal flaw detection assembly adapted to pass a circumferential magnetic field through a tubular member and a transverse flaw detection assembly adapted to pass a longitudinal magnetic field through the tubular member. The magnetic fields cause congregation of a ferromagnetic particles sprayed on the tubular member in a magnetic particle inspection fluid. The congregation of ferromagnetic particles indicates a flaw in the tubular member. The magnetic inspection station includes a clamping apparatus positioned closely adjacent to the magnetic inspection station and adapted to support the tubular member within the magnetic inspection station and exert a compensating force on the tubular member to resist the magnetic forces generated by the longitudinal flaw detection assembly and the transverse flaw detection assembly.

The invention relates to a three-dimensional vector magnetic moment measuring instrument. The three-dimensional vector magnetic moment measuring instrument may include a vibration unit for manipulating a sample rod and enabling a sample installed on the sample rod to vibrate in one direction, an external magnetic field applying unit used for applying an outer magnetic field to the sample, a firs induction coil group to a third induction coil group which are arranged around the sample and are used for measuring the three-dimensional components of the vector magnetic moment of the sample, and a signal processing unit which receives measurement signals from the firs induction coil group to the third induction coil group, and calculates the three-dimensional vector magnetic moment of the sample based on the measurement signals. According to the three-dimensional vector magnetic moment measuring instrument of the invention, the measurement signals of one or a plurality of detection coils in the firs induction coil group, the second induction coil group and the third induction coil group are combined in a parallel and series manner. The three-dimensional vector magnetic moment measuring instrument can realize synchronous measurement of the number and polarity of magnetic charges contained in the sample.

The invention provides a high-precision magnetic nano temperature estimation method and system based on Fokker-Planck. The method comprises: constructing a magnetic nanoparticle temperature estimationmodel through a Fokker-Planck formula, measuring the magnetization response harmonic amplitude and phase information of the magnetic nanoparticles multiple times through a magnetic field informationdetection device, and fitting model parameters in the magnetic nanoparticle temperature estimation model; placing a sample to be detected in the magnetic field information detection device, measuringand substituting the harmonic amplitude and phase information of the sample under the excitation of an external magnetic field into the preset magnetic nanoparticle temperature estimation model, and solving the magnetic nanoparticle temperature information. According to the invention, the temperature information of the magnetic nanoparticles under the excitation of a medium-high frequency magneticfield can be accurately obtained. The problem that the conventional Langevin Function is not suitable on occasions of medium-high frequency excitation is solved, the application fields of magnetic nano temperature measurement and magnetic nano particle imaging technologies are expanded, and the measurement precision and the time-space resolution are improved.

A detector includes a detection winding (21, 22, 27, 28), a detection winding measurement section (24), and a detection section (23). A magnetic core (11, 61, 71, 81, 92) has a hole (11b, 11cm 11e, 11f, 11g, 11h, 61d, 61e, 71b, 81b, 92b) penetrating the magnetic core along a non-uniform cross section. The detection winding includes a wire inserted into the hole and surrounding a periphery of a detection region (11dx, 11dy, 11ix, 11iy) that is a part of the non-uniform cross section and has a magnetic flux density different from an average magnetic flux density of the non-uniform cross section. The detection winding measurement section performs a measurement relating to an electromotive force induced by the detection winding. The detection section detects a magnetic bias, a magnetic saturation, or an amount of magnetic flux in the magnetic core based on a measurement result of the detection winding measurement section.

A method of detecting the presence of a substance (32) to be detected on a surface of a substrate (21), the method comprising: i) providing magnetic particles (35) to the substrate (21) for binding with the substance (32) to be detected; and ii) determining the presence of the substance (32) to be detected by detecting the magnetoresistive effect of the magnetic particles (35) bound to the substance (32) to be detected on a magnetoresistive element (40) positioned proximate the substrate surface.

A method for estimating the magnetization level of one or more permanent magnets established in one or more permanent magnet rotors of a wind turbine generator includes the steps of: establishing one or more magnetization sensors at the stator of the generator, connecting the one or more magnetization sensors to a measuring mechanism, processing measured data in the measuring mechanism, and establishing values of magnetization. Furthermore the invention also relates to a wind turbine.

A detection system and method uses an implantable magnetic marker comprising at least one piece of a large Barkhausen jump material (LBJ). The marker is deployed to mark a tissue site in the body for subsequent surgery, and the magnetic detection system includes a handheld probe to excite the marker below the switching field for bistable switching of the marker causing a harmonic response to be generated in a sub-bistable mode that allows the marker to be detected and localised. The marker implanted may also be shorter than the critical length required to initiate bistable switching of the LBJ material.

An AMR array magnetic position sensing system for improved sensor flexibility and improved air gap performance is disclosed. A pair of magnets can be enclosed in a magnet carrier that moves along a path and located above an array of AMR position sensors. The magnets are generally magnetized through the length of the magnets, and the magnets are positioned in the carrier such that an angle between the magnets exists in a manner similar to an angle made by AMR runners on a surface of the AMR positions sensors to create magnetic flux lines thereof. The AMR position sensors come into contact with the uniform magnetic flux lines to sense a change in linear and angular position associated with the magnet carrier. The output signal generated by the AMR position sensors have less susceptibility to variations in air gap as the angles of the magnetic flux lines generated by the magnets do note change with respect to air gap variation.

The invention discloses a demagnetization detection apparatus and detection method of a permanent magnet synchronous linear motor. The demagnetization detection apparatus of a permanent magnet synchronous linear motor is characterized in that a linear motor with a demagnetization detection apparatus is used as a detection motor; the demagnetization detection apparatus takes an aluminium block as apedestal; a gaussmeter probe is fixedly arranged on the aluminium block by means of a clamp, so that the probe is arranged in the space air gap of the linear motor to be detected; adjusting bolts areused to adjust the positions of three detection points of the gaussmeter probe in space air gap of the linear motor to be detected; and the demagnetization detection apparatus is used for detecting distribution of air-gap flux density at the positions of the three detection points of the linear motor to be detected so as to realize demagnetization detection. The demagnetization detection apparatus and detection method of a permanent magnet synchronous linear motor can determine the difference distribution between the flux density to be detected and normal flux density distribution, and can extract the demagnetization fault characteristics. The demagnetization detection apparatus and detection method of a permanent magnet synchronous linear motor can realize accurate identification of thedemagnetization fault by means of a PNN classification algorithm.

The invention provides a quick demagnetization method based on magnetic medium characteristics. Recognition module by magnetic medium, basic information such as brands, types, capacities and production time of to-be-demagnetized magnetic media is acquired by adopting multi-source sensing cooperation modes such as bar code scanning and image collection, magnetic medium recognition is realized by means of a data processing technology and a magnetic medium recognition algorithm, and then characteristic information such as a magnetic recording mode, material characteristics and coercive force of the to-be-demagnetized magnetic media is extracted; through a demagnetization parameter optimization setting module, obtaining optimization setting values of demagnetization parameters such as the magnetic field intensity and the demagnetization angle of the to-be-demagnetized magnetic medium based on the demagnetization optimization setting model; a degaussing parameter set value is tracked through a degaussing magnetic field closed-loop control module in combination with domain expert knowledge by adopting a closed-loop control mechanism integrating a magnetic field control algorithm, a charging and discharging device, a magnetic field generation device, a magnetic field and an environmental characteristic measurement sensor, and quick degaussing of a magnetic medium to be degaussed is completed.

Stray magnetic fields created by non-symmetrical magnetisation of the permanent magnets in a rotating magnet array of a magnetic bearing assembly, when used in turbo molecular pumps, can cause significant problems to devices such as scanning electron microscopes. In order to minimise the stray fields, at least the dipole and quadrupole moments of each magnet in the array is first measured. The magnets in the array are then arranged relative to one another such that both the dipole and quadrupole moments are minimised, thus minimising the stray magnetic field when the magnet array rotates in the turbomolecular pump.

A system includes a probe assembly having sensing circuitry configured to sense at least one parameter relating to a rotating machine and a cable coupled to the sensing circuitry. The probe assembly also includes a molded probe body that is integrally molded about the cable and the sensing circuitry and a machined groove disposed on the molded probe body. The machined groove includes a machined surface.

A magnetic field sensing apparatus including a magnetic flux concentrator and a plurality of magnetoresistance units is provided. The magnetic flux concentrator has a top surface, a bottom surface opposite to the top surface, and a plurality of side surfaces connecting the top surface and the bottom surface. The magnetoresistance units are respectively disposed beside the side surfaces. The magnetoresistance units are electrically connected to form at least one kind of Wheatstone full bridge in three different periods, so as to measure magnetic field components in three different directions, respectively, and to cause the at least one kind of Wheatstone full bridge to output three signals corresponding to the magnetic field components in the three different directions, respectively.

The present invention discloses a rock and ore sample magnetic parameter measurement device and method thereof for geological exploring. The device comprises a supporting plate, a supporting bar, an arc angle regulation rack, a cantboard, a specimen box, a probe, an adjustable pole, a horizontal bubble instrument, a precision pin and a laser emitter. The laser emitter and the arc angle regulation rack are employed to correct the inclined angle of an incline plate of the device prior to the measurement, and the accuracy the disposing position of the specimen is improved. The horizontal bubble instrument is able to better calibrate the accuracy of the position of the supporting plate. Besides, the probe and the supporting plate are integrally arranged and are very convenient for using, a sliding block and a spherical hinge are used for easily regulating the position of the probe, the measurement of the distance between the probe and the specimen box are convenient, and the measurement precision and the measurement efficiency are effectively improved.

The invention discloses a remanence evaluating and demagnetizing device of a power transformer. In a main circuit, two ends of a switch power are respectively connected with a filter capacitor and a resistor R0 in parallel, a forward end of the switch power is connected with a main switch T5 in serial, a switch T6 and a resistor R1 serial branch, a switch 1 and a switch 2 serial branch, a switch 3and a switch 4 serial branch are connected at the rear end of the main switch T5 in parallel, a drive circuit is connected with drive ends of the main switch T5, the switch T6, the switch 1, the switch 2, the switch 3 and the switch 4, and a control circuit is connected with the drive circuit and is used for sending an instruction to the drive circuit. The device provides reference for rapid, accurate demagnetization, is more intelligent, can demagnetize rapidly and thoroughly, and greatly shortens field demagnetization time and improves demagnetization effect.

A metal detector includes means for reducing the induction of eddy currents in conductive elements of a sensor head. The aim of this invention is to remove the effect of small pieces of conductive material, located within or close to the sensor head, being seen as sought targets as the sensor head is moved over magnetic matrix. The means is to surround the conductive material with material with high magnetic permeability and low losses in a time-varying magnetic field, say low-loss ferrite. This will prevent the reflected field from illuminating the conductive material so eddy currents are not generated.

The invention provides a single-piece permeameter, a device for measuring a single-piece test sample and a measuring method. The single-piece permeameter comprises U-shaped double magnetic yokes, a frame, a primary winding, an H coil pair and a secondary winding, wherein the frame is positioned between the U-shaped double magnetic yokes; the primary winding is distributed on the frame; a to-be-tested test sample is arranged in the frame; the H coil pair is positioned below the to-be-tested test sample; the secondary winding is positioned in the primary winding; the secondary winding comprisesthree sub-windings which wind separately, namely a left-side winding, a middle winding and a right-side winging; each of the left-side winding, the middle winding and the right-side winding is provided with an input port and an output port; and one or more of the left-side winding, the middle winding and the right-side winding are selected to connect by connecting the input ports and the output ports of different sub-windings. Through implementation of the invention, the accuracy of measuring the intensity of the magnetic field of the to-be-tested test sample is improved; and magnetic propertyparameters in different areas of the to-be-tested test sample can be measured, the adaptability is improved, and the operation is simple and convenient.

The invention relates to a claw pole magnetic property nondestructive testing device and method adjustable in test temperature. The device comprises a pedestal arranged in an incubator in a magnetismisolating way, a winding ferrule and an excitation coil which are arranged on the pedestal from inside to outside as well as a to-be-tested claw pole part arranged at the top of the pedestal, whereina measuring coil is arranged in the to-be-tested claw pole part, a magnetic conductive ring forming a magnetic field loop with the to-be-tested claw pole part is arranged outside the measuring coil, the excitation coil is connected with a direct current magnetic property measuring instrument and receives an excitation voltage, the measuring coil outputs an induced current to the direct current magnetic property measuring instrument by generating the induced current, the direct current magnetic property measuring instrument records an output excitation current, the detected induced current is converted into an induced voltage and integration is performed on the induced voltage in the time domain to obtain magnetic induction intensity, the whole magnetizing curve of the to-be-tested claw pole part is obtained through measuring and calculating, and magnetic permeability of the claw pole part is represented. The device provided by the invention constructs operating magnetic field distribution highly similar to the actual generator by simulating temperature conditions in a generator operation process according to magnetic circuit characteristics of a claw pole type generator, thus rapidtesting is performed.

The present invention relates to an arrangement (10) for measuring small amounts of a first medium (202) in a third medium (206) and / or of a substance in the first medium (202), said third medium (206) comprising said first medium (202) and a second medium (204), said second medium (204) comprising a known concentration of a magnetic material, wherein said arrangement comprises: - magnetization means (12) for providing a variable magnetic field (20) in a region of action (22), in which a probe (18; 208) of said third medium (206) is placed for measurement, - receiving means (14) for acquiring a detection signal of the magnetization of said probe (12) in said region of action (22) after application of said variable magnetic field (20), and - evaluation means (214) for evaluating said detection signal and comparing it to calibration measurements of the magnetization of at least one calibration sample to derive an information about the amount of said first medium (202) in said third medium (206) and / or of said substance in said first medium (202).

An apparatus comprising at least one first signal loop configured to receive a first signal; at least one second signal loop magnetically coupled with the first signal loop configured to generate a second signal; a signal processor configured to monitor the second signal and determine the presence of at least one metal object dependent on the second signal.

The invention provides a Hall sensor and a sensing method, and a corresponding device. A Hall sensor may include a Hall sensing element configured to produce a Hall voltage indicative of a magnetic field when traversed by an electric current, and a first pair of bias electrodes mutually opposed in a first direction across the Hall sensing element. The Hall sensor may include a second pair of bias electrodes mutually opposed in a second direction across the Hall sensing element. The Hall sensor may include a first pair of sensing electrodes mutually opposed in a third direction across the Hall sensing element, and a second pair of sensing electrodes mutually opposed in a fourth direction across the Hall sensing element. The fourth direction may be orthogonal to the third direction, each sensing electrode being between a bias electrode of the first pair and a bias electrode of the second pair.