113results about "Susceptibility measurements" patented technology

There is provided an implantable marker for use in surgical guidance. The implantable marker comprises one or more ferromagnetic elements formed of at least one ferromagnetic material and at least one diamagnetic element formed of at least one diamagnetic material. The at least one diamagnetic material comprises graphite having a substantially isotropic grain structure and the one or more ferromagnetic elements are juxtaposed the at least one diamagnetic element.

An implantable marker for imaging and surgical guidance by susceptometry comprising one or more pieces of a ferromagnetic material having a total length to diameter ratio of at least about 500, and a total volume of less than about 1×10−11 m3. The one or more pieces of ferromagnetic material may have a high initial relative permeability (μr,i)>about 1000. Also disclosed is a detection system for locating an implantable marker comprising such an implantable marker; at least one drive coil arranged to excite the marker with an alternating magnetic field, and at least one sense coil arranged to detect a signal received from the excited marker; a magnetic field generator arranged to drive an alternating magnetic field through the at least drive coil; and at least one detector arranged to receive the signal from the sense coil and detect one or more harmonics of the drive frequency in the received signal.

The present invention relates to a magnetic susceptibility inversion method and system, the method comprising: S1, obtaining a spatial domain residual based on observed magnetic field intensity and theoretical magnetic field intensity; S2, expressing the spatial domain residual by two-dimensional discrete Fourier inverse transform based on wave number domain residual; S3, obtaining a wave number domain model perturbation based on the spatial domain residual, and further obtaining a spatial domain model perturbation based on Fourier inverse transform; S4, obtaining a magnetic susceptibility inversion model based on the spatial domain model perturbation. The present invention reduces the required memory space, improves the calculation efficiency, and further improves the inversion efficiency.

The present invention relates to a probe for locating a magnetic marker for use during surgery. The probe comprises at least two first coils (3a, 3b) and at least one second coil (5) arranged substantially coaxially on a longitudinal axis of the probe for measuring the proximity of a magnetic marker to the probe, and a baseline voltage sensing device (7) comprising a first elongated conductor defining a conductive path extending partially around the axis of the probe. The conductive path is constructed and arranged to induce a balanced voltage in the sensing coils that, in use, at least partially offsets the baseline voltage. Methods of manufacturing such a probe, methods of configuring such a probe for use in sensing magnetic markers, and detection devices for locating a magnetic marker during surgery are also disclosed.

The invention discloses a sulfur-containing magnetite beneficiation method which specifically comprises the following steps: S1, raw material preparation: crushing sulfur-containing magnetite to obtain small-particle sulfur-containing magnetite; s2, physicochemical property determination: detecting the particle size of the small-particle sulfur-containing magnetite, the content of magnetite in the small-particle sulfur-containing magnetite and the content of sulfur minerals in the small-particle sulfur-containing magnetite; s3, magnetic separation: according to the physicochemical properties of the small-particle sulfur-containing magnetite detected in the step S2, automatically controlling the magnetic field intensity of a magnetic separation process through a controller, and carrying out magnetic separation to obtain magnetite and sulfur-containing ore; the magnetic field intensity of the magnetic separation process is dynamically adjusted according to the iron ore particle size of the sulfur-containing magnetite, the magnetite content in the sulfur-containing magnetite and the sulfur mineral content, the trends of iron minerals and sulfur minerals are accurately controlled, optimal adjustment of the element trends is achieved, and the recovery rate of iron and sulfur is increased.

A probe for locating a magnetic marker for use in surgery. The probe comprises at least two first coils (3a, 3b) and at least one second coil (5) which are arranged substantially coaxially on a longitudinal axis of the probe for measuring the proximity of a magnetic marker to the probe, and a baseline voltage taring device (7) comprising a first elongate conductor which defines a conducting path extending partially around the probe axis. The conducting path is configured and arranged such that in use the balancing magnetic field induces a balancing voltage in a sense coil that at least partially offsets the baseline voltage. Also disclosed is a method of manufacturing such a probe, a method of setting up such a probe for use in sensing a magnetic marker, and detection apparatus for locating a magnetic marker during surgery.

The invention relates to a superconducting quantum interference probe and a manufacturing method thereof. The method comprises the steps that an insulating layer stacked on a chip substrate is formed, and the chip substrate comprises a circuit layer; a needle body stacked on the insulating layer is formed, and the end, away from the insulating layer, of the needle body is provided with a needle point area; forming a prefabricated superconducting layer laminated on the needle body and the insulating layer; and etching the prefabricated superconducting layer to form a hole corresponding to the needle point region, and forming two slits which extend along the direction far away from the hole and are arranged at intervals with the hole, so as to obtain a superconducting quantum interference loop surrounding the hole based on the prefabricated superconducting layer. According to the method, the superconducting quantum interference loop located at the needle point can be integrated on the chip substrate.

A sensor apparatus for determining and / or monitoring a process variable of a medium in a containment includes: a crystal body including at least one defect; a magnetic field system for producing a magnetic field in the region of the crystal body and in the region of the medium within the containment, wherein the crystal body and the magnetic field system are arrangeable from the outside at a wall of the containment; a detection unit for detecting a magnetic field-dependent, fluorescent signal from the crystal body, wherein the detection unit has an excitation unit for optical exciting of the defect and a detector for detecting the fluorescent signal; and an evaluation unit for ascertaining at least one piece of information concerning the process variable based on the fluorescent signal.

The invention relates to the technical field of ultra-low field magnetic resonance systems, in particular to a battery charge state detection method and system based on closed-loop adaptive ultra-low field MRI, and the method comprises the steps: collecting the phase change of a water molecule H signal caused by the magnetic field disturbance of a to-be-detected battery, and reconstructing a first signal phase image; extracting to obtain a high-information-content area mask, and then performing resampling to obtain a second signal phase image; and inputting the second signal phase image into a state-of-charge detection model to predict a state-of-charge value of the to-be-detected battery. In order to solve the problem that a battery magnetic resonance detection scheme in the prior art needs to adopt a high-field magnetic resonance system and is not beneficial to production line use, detection equipment is replaced with an ultralow-field magnetic resonance system, so that structures such as a shielding room in a traditional magnetic resonance system are omitted, and a high-information-content area is positioned firstly, so that the detection efficiency is improved; and resampling is carried out on the region, so that the imaging precision is improved, and the accuracy of state of charge estimation of the detection model is improved.

The invention discloses a method for calculating a quantitative magnetic susceptibility image through total field inversion based on a Green function. The method is used for separating a background magnetic field and reconstructing a whole-brain quantitative magnetic susceptibility image in magnetic resonance imaging. According to the boundary element method full-field inversion method, filtering and regularization processing on tissue magnetic susceptibility are prevented from being additionally introduced when background field interference is removed, the background field can be effectively separated, a whole-brain quantitative magnetic susceptibility image can be reconstructed, the boundary erosion phenomenon cannot occur, and the boundary element method full-field inversion method particularly shows excellent performance in a cortex area. According to the method, a fast multipole method is adopted to efficiently process storage and calculation of a dense matrix generated by a boundary integral equation.

The present disclosure relates to implantable markers for imaging and surgical guidance. An implantable marker for imaging and surgical guidance by susceptibility measurement, comprising one or more pieces of ferromagnetic material having a total aspect ratio of at least about 500 and a total volume of less than about 1 x 10-11 m3. The one or more pieces of ferromagnetic material may have a high initial relative permeability (μr,i) > about 1000. Also disclosed is a detection system for locating an implantable marker, comprising such an implantable marker; at least one drive coil arranged to excite the marker with an alternating magnetic field, and at least one sensing coil arranged to detect a signal received from the excited marker; a magnetic field generator arranged to drive an alternating magnetic field through the at least one drive coil; and at least one detector arranged to receive a signal from the sensing coil and detect one or more harmonics of the drive frequency in the received signal.

An implantable susceptometry marker (1001) for use in a surgical guide includes one or more ferromagnetic elements (1004a, 1004b, 1004c) and at least one diamagnetic element (1003), the one or more ferromagnetic elements being formed from at least one ferromagnetic material having a specific initial permeability of at least about 10,000 and a saturation induction Bs of less than about 1.5 T, and the at least one diamagnetic element having a specific initial permeability of at least about -0.16 x 10 -4 and a total volume of said diamagnetic material within said marker is about 100 to 10,000 times greater than a total volume of said ferromagnetic material.

Magnetic core assemblies include a skewing feature that introduces transverse components into the power flux density vector are disclosed herein. A magnetic core assembly comprises a lower core having a center section and an upper core having a center section. The center sections are aligned to form a center post. A power winding that receives current is wrapped around the center post. The core assembly further comprises a power flux density vector that has transverse and non-transverse components. The transverse components have a higher magnetic reluctance than the non-transverse components. When the assembly is used with a transverse winding, the transverse components from the magnetic core assembly produce a transverse voltage waveform on the transverse winding. The transverse voltage waveform may be observed to detect a change in the sign of the slope of the transverse voltage waveform. The change in the sign of the slope indicates magnetic saturation.

A probe for locating magnetic markers used in surgery. The probe includes: at least two first coils (3a, 3b) and at least one second coil (5), which are arranged substantially coaxially on the longitudinal axis of the probe for measuring the proximity of the magnetic marker to the probe; and a reference voltage balancing device (7) comprising a first elongated conductor defining a conductive path extending partially around the probe axis. The conductive path is configured and arranged such that, in use, a balancing magnetic field induces a balancing voltage in the sensing coil that at least partially cancels out the reference voltage. Methods for manufacturing such a probe, methods for setting such a probe for sensing magnetic markers, and detection devices for locating magnetic markers during surgery are also disclosed.

The invention relates to a measuring assembly (10) for determining a distribution of the magnetic gradient force, comprising a probe body (20) in which a hollow space (25) is formed. There is a probe suspension (30) in the hollow space (25), which contains a fluid (31) and at least one diamagnetic particle (35). A measuring device (40) is designed to determine a distance d of the diamagnetic particle / s (35) relative to a reference plane (29) on the probe body (20). A probe positioning unit (60) is designed to determine a geometric location of the hollow space (25) and / or the at least one particle (35) relative to a stationary reference location (69) outside the probe body (20).

The utility model discloses a magnetic susceptibility detection device. The magnetic susceptibility detection device comprises a detector main body, a material containing part, a magnetic part, a moving assembly and a detection assembly, the detector body is provided with a detection position, and the material containing part is movably arranged at the detection position and used for containing materials. The magnetic part is arranged on the outer side of the detection position and can apply magnetic attraction force to materials in the material containing part. The moving assembly is arranged on the detector main body and acts on the magnetic piece to drive the magnetic piece to be close to or away from the material containing piece; the detection assembly is provided with a detection part, the detection part has a first state and a second state, the detection part is in the first state when the material containing part is located at the detection position, and the moving assembly can drive the magnetic part to move close to the material containing part; when the material containing part is separated from the detection position, the detection part is in a second state and generates an electric signal; the moving assembly stops moving in response to the electric signal. The magnetic susceptibility detection device is more convenient to operate, and the visualization degree of the detection result is higher.

A probe (303; 403) for sensing a magnetic marker, comprising a first coil set (313; 413) including a first coil of a first coil type, e.g., a sense coil (305; 405), disposed between a first pair of coils of a second coil type, e.g., a drive coil (301a, 301b; 401a, 401b) connected in series, and a balance element (317; 417) axially spaced from the first coil set (313; 413) along the length of the probe (303; 403). The balance element (317; 417) is configured or arranged to generate a sense voltage that fully offsets, partially offsets, or minimizes a sense voltage induced in one or more sense coils (305; 405) of the first coil set from the drive coil or coils (301a, 301b; 401a, 401b). A detection system is also disclosed, comprising the probe (303; 403), a magnetic field generator configured to drive an alternating magnetic field through the drive coils (301a, 301b; 401a, 401b) of the first coil set and the balance element (317; 417), and at least one detector configured to receive a signal indicative of a sensed voltage.

The invention relates to a method for measuring relative concentrations of materials in a mixture, comprising the following steps: • a / providing an emission coil (2) and at least one reception coil (3.1, 3.2); • b / providing a mixture (P, E) comprising n materials having different magnetic susceptibilities (χ 1, χ 2,.. χ n); • c / introducing the mixture into the reception coil; • d / using a voltage generator to supply the emission coil at at least one nonzero excitation frequency so as to generate an excitation magnetic field; • e / measuring the signal of the voltage induced in the reception coil; • f / determining relative concentrations of the n materials based on comparison between the overall susceptibility of the mixture as obtained through the voltage measurement in step e / and that of a reference mixture for which the relative concentrations of said n materials are known. The invention also relates to the associated system.

Example medical systems useful in performing treatment under magnetic resonance imaging and related devices, kits, and methods are described. An example medical system includes a first medical device and a second medical device. The first medical device has a first passive marker. The first passive marker is formed of a first material that has a first magnetic susceptibility. The second medical device has a second passive marker. The second passive marker is formed of a second material that has a second magnetic susceptibility. The second passive marker creates an image artifact under MRI. The image artifact created by the second passive marker is altered under MRI when the first passive marker overlaps the second passive marker.

The invention relates to a rock ore specimen magnetic parameter measuring device and method for geological exploration, and belongs to the technical field of geological exploration, the rock ore specimen magnetic parameter measuring device comprises a tripod, a measuring device, a mounting box, a mounting plate and a floating member, the top surface of the mounting box is open, the bottom of the mounting box is provided with a first fixing member, the floating member is located in the mounting box, and the tripod is arranged on the mounting plate; the measuring device is arranged on the tripod and used for measuring magnetic parameters of the specimen; the mounting plate is embedded in the top surface of the floating part, a fixing rod is slidably arranged in the mounting plate, and a first driving part for driving the fixing rod to slide is arranged in the mounting plate; a plurality of slideways are formed in the top surface of the mounting plate, the number of the slideways is consistent with that of the tripod kickstands, the slideways are uniformly distributed along the center of the mounting plate, sliding blocks are arranged in the slideways in a sliding manner, the tripod kickstands are inserted into the sliding blocks, and a second driving part used for driving the sliding blocks to slide at the same speed at the same time is arranged on the mounting plate. The method has the advantage of improving the measurement efficiency and precision of the magnetic parameters of the specimen.

Systems and methods for quantitative susceptibility mapping ("QSM") using magnetic resonance imaging ("MRf") and a localized processing technique are described. A field-shift map is processed based on localized regions of local field perturbations. These localized field-shift regions are processed using established QSM algorithms, or using direct dipole inversion techniques, to compute regional susceptibility distributions from the localized field shift information. When the localized regions correspond to subvolumes of the field-shift map, local susceptibility maps can be generated and combined to form a composite quantitative susceptibility map. By computing regional susceptibility distributions based on localized field-shift information, residual streaking artifacts in the susceptibility map are constrained to the individual volumes from which they originate, thereby eliminating their propagation through the image,

A method of diagnosing internal characteristics of a device includes applying a strong magnetic field to the device. The method can include reducing the strong magnetic field at a location of one or more sensors. At least one of the one or more sensors is proximate to the device. The method can include measuring induced magnetic fields around the device. The method can include measuring induced or intrinsic electrical current flow. The method can include measuring intrinsic magnetic properties. The induced magnetic fields can include diagnostic information on properties of the device and how the properties change over time. The device may be, for example, a battery, a capacitor, a supercapacitor, or a fuel cell. The presented measurement of magnetic susceptibility can be performed on materials, solutions, chemical substances, or tissue samples.

An implantable marker for use in a surgical guide is provided, the implantable marker including one or more ferromagnetic elements formed from at least one ferromagnetic material and at least one diamagnetic element formed from at least one diamagnetic material, the at least one diamagnetic material including graphite having a substantially isotropic grain structure, and the one or more ferromagnetic elements juxtaposed with the at least one diamagnetic element.

Example medical systems, and related devices, kits, and methods, are described that can be used for treatment under magnetic resonance imaging. An example medical system includes a first medical device and a second medical device. The first medical device has a first passive marker. The first passive marker is formed of a first material having a first magnetic sensitivity. The second medical device has a second passive marker. The second passive marker is formed of a second material having a second magnetic sensitivity. The second passive marker creates an image artifact under MRI. When the first passive marker overlaps the second passive marker, an image artifact created by the second passive marker is changed under MRI.

An external field response distribution visualization device (100) includes: a sensing circuit (110) that induces a first field component from each of a plurality of sensing positions; a sensor (130) that senses the intensity of the field at a plurality of sensing positions for each of the plurality of sensing positions; and an information processing circuit (150) that generates an image representing the external field response distribution, the information processing circuit (150) calculating a sensing position-dependent field function that inputs a sensing position and a sensing position and outputs the intensity of the field using the sensing result as a boundary condition, calculating an imaging function that is a function that inputs an imaging target position and outputs an image intensity, is a function determined based on the intensity output from the sensing position-dependent field function by inputting the imaging target position to the sensing position-dependent field function, and generating the image based on the imaging function.

A static magnetic field generator (2) generates a region without a magnetic field. An alternating magnetic field applicator (3) applies an alternating magnetic field to the region without a magnetic field. A detection coil (1) has an axis parallel to the direction of the alternating magnetic field for detecting the magnetization signal. A measuring device (4) is connected to the detection coil (1). A resonant frequency variable device (5) includes a capacitor connected in parallel with the detection coil (1) to adjust the resonant frequency of the detection coil (1) and the measuring device (4). The capacitance of the capacitor is adjusted in such a way that the resonant frequency of the closed circuit including the detection coil (1), the measuring device (4), and the resonant frequency variable device (5) containing the capacitor is consistent with the frequency of the higher harmonic signal.

An implantable marker for imaging and surgical guidance by susceptometry comprising one or more pieces of a ferromagnetic material having a total length to diameter ratio of at least about 50, and a total volume of less than about 1 × 10-10m3. The one or more pieces of ferromagnetic material may have a high initial relative permeability (µr,i) > about 1000. Also disclosed is a detection system for locating an implantable marker comprising such an implantable marker; at least one drive coil arranged to excite the marker with an alternating magnetic field, and at least one sense coil arranged to detect a signal received from the excited marker; a magnetic field generator arranged to drive an alternating magnetic field through the at least drive coil; andat least one detector arranged to receive the signal from the sense coil and detect one or more harmonics of the drive frequency in the received signal.

A kind of low temperature insert for AC magnetic susceptibility test, including terminal box, sample tube, sample rod and protective cover, characterized by: the terminal box, sample tube, protective cover are hollow structure capable of accommodating sample rod, and are connected in turn from top to bottom;Coil group is provided in the protective cover, the coil group includes excitation coil and secondary coil, the excitation coil and secondary coil are wound on two coil holders respectively, constitute concentric cylindrical structure, and the excitation coil is located in the outer layer of the secondary coil;Electrical connector is provided on the outer wall of the terminal box, for connecting the coil group via electrical lead line.The technical scheme based on the present application simplifies the manufacturing process of low temperature insert and maintenance replacement cost, while reducing error, and the test result is accurate.