177results about "Measurements using NMR" patented technology

A magnetic resonance imaging system is presented, including: a magnetic resonance imager (302) comprising a superconducting magnet (304) surrounding a bore (306); a cooling system configured to cool the superconducting magnet through conduction cooling; a frame (520) rotatably supporting the magnetic resonance imager; an actuator configured to move the magnetic resonance imager in a plurality of predetermined examination positions between a horizontal orientation and a vertical orientation of a main static magnetic field associated to the superconducting magnet; and a patient support (320) configured to support a patient in any of the plurality of predetermined examination positions.

The invention relates to a magnetic resonance imaging (MRI) device (1) which is designed to image a substantially metallic component. The magnetic resonance imaging device comprises means (b '') for generating a polarized magnetic field intended to be applied to said component (a), radio frequency (RF) means (g) for exciting said component (a), detection means cooperating with antenna means for delivering a magnetic resonance imaging (MRI) signal, and means for processing said MRI signal for delivery with respect to said component (a) and a device for detecting feature information of the state. The component (a) is subjected to a very weak field of less than 10 mT, and the detection means comprise a pickup coil (h) magnetically coupled with the polarization means (b '') and the radio frequency means (g) and operating as a flux concentrator, and an SQUID (Superconducting Quantum Interference Device) detector arranged downstream of said pickup coil (h) via a transformer.

The invention provides an integrated deuterium-hydrogen double nuclear magnetic resonance coil, which comprises a barrel and a plurality of single-channel double-frequency coils, and is characterized in that the barrel is of a hollow barrel-shaped structure; a plurality of single-channel double-frequency coils are overlapped and laid on the outer surface of the cylinder in a surrounding manner; each single-channel double-frequency coil comprises a coil unit, a first capacitor C1, a second capacitor C2, an input and output matching circuit and a double-frequency switching circuit, the first capacitor C1 and the second capacitor C2 are connected to the coil unit in series, and the double-frequency switching circuit is connected to the two ends of the second capacitor C2 in parallel. And the input and output matching circuit is connected to the two ends of the first capacitor C1 in parallel so as to correspondingly match the input and output of the working frequencies of the two coils. According to the invention, the integrated deuteron and hydrogen core dual-frequency working mode switching is realized through the same wiring structure, and the mutual influence caused by repeated positioning of a plurality of coils and multi-structure nesting is avoided.

The subject invention pertains to a method that involves at least three steps: (1) acquisition of a NMR data set or spin relaxation curve for plasma, serum or whole blood samples, (2) analysis of the NMR data or relaxation curve to extract the T2 relaxation times for water (or surrogates thereof), and (3) conversion of the water T2 (or surrogates thereof) into a measure of someone's health status (referred to as a T2 health score depending on the T2 value associated with the score). The T2 health score utilizes a statistical database derived from previous studies of subjects of normal, healthy individuals to those having varying degrees of hidden or subclinical metabolic abnormalities, such as inflammation, insulin resistance, lipid abnormalities (dyslipidemia), oxidative stress or other abnormalities, and provides a measure of a subject's overall health status.

A method of determining a ratio of hydrogen to methane produced from a partially depleted shale gas reservoir comprising an organic nanopore system, an inorganic pore system, and a micro-fracture system, and housing stored hydrogen, comprises: obtaining a core sample from the reservoir, and subjecting the core sample to 1H Nuclear Magnetic Resonance (NMR) testing to obtain respective T2 and T1-T2 relaxation times for methane and for hydrogen in each one of the organic nanopore system, the inorganic pore system, and the fracture system.

Disclosed herein is a magnetic resonance imaging (MRI) coil assembly comprising: a set of one or more quantum sensors and associated set of one or more radio frequency coils respectively, wherein each radio frequency coil of the set of one or more radio frequency coils is configured to perform radio frequency excitation in an object to be imaged for inducing a magnetic resonance signal from the object; wherein each quantum sensor of the set of one or more quantum sensors is configured to receive a signal induced by the magnetic resonance signal in the respective radio frequency coil and provide an optical signal representing the MRI signal through an optical link. The MRI coil assembly comprises an optical signal processing unit that is configured to receive through the optical links the one or more optical signals and to digitize the one or more optical signals.

The invention discloses a nuclear magnetic resonance passive shimming module design method and device based on Gaussian splashing, and relates to the technical field of precision electromagnetic field optimizing.The nuclear magnetic resonance passive shimming module design method comprises the steps that initialization is conducted in a design domain of a passive shimming module, and an initial parameter set of all Gaussian splashing particles is obtained; constructing a mapping relation between the equivalent magnetic moment and the magnetization weight factor of each Gaussian splashing particle and between the intrinsic magnetization intensity and the scaling vector of the magnetic material, and constructing a magnetic field intensity calculation model; inputting the initial parameter set of all Gaussian splashing particles and the real magnetic field intensity into a Gaussian splashing particle parameter set iterative optimization algorithm, and calculating and predicting the magnetic field intensity through a magnetic field intensity calculation model; and based on the predicted magnetic field intensity, the real magnetic field intensity, the magnetization weight factor vector and the center position vector, constructing a multi-objective loss function and performing iterative optimization to obtain an optimized parameter set and manufacture a passive shimming module. The method solves the problem of low precision and efficiency of compensating a magnetic field with a complex shape.

The invention discloses a security check stand column ferromagnetic detection system for a nuclear magnetic resonance room, which comprises a ferromagnetic detection device, a door opening detection device and an alarm device, and is characterized in that the ferromagnetic detection device and the door opening detection device are arranged close to a door of the nuclear magnetic resonance room; the door opening detection device is electrically connected with the ferromagnetic detection device; the ferromagnetic detection device comprises a magnetic field induction assembly and a signal processing assembly, the output end of the magnetic field induction assembly is electrically connected with the input end of the signal processing assembly, and the magnetic field induction assembly sends a magnetic field change signal to the signal processing assembly; the signal processing assembly comprises a band-pass filtering and amplifying unit, and the band-pass filtering and amplifying unit is used for performing amplification, high-frequency filtering and low-frequency filtering coupling processing on the magnetic field change signal to obtain a processing signal; and the alarm device is electrically connected with the signal processing assembly and is used for acquiring and identifying the processing signal and carrying out alarm work according to an identification result, so that the probability of metal leak detection or false detection is effectively reduced.

According to various embodiments, a magnetic resonance imaging system is provided. According to various embodiments, the system includes a housing having a front surface, a permanent magnet for providing a static magnetic field, a radio frequency (RF) transmission coil, and at least one gradient coil group. According to various embodiments, the RF transmission coil and the at least one gradient coil group are positioned close to the front surface. According to various embodiments, the RF transmission coil and the at least one gradient coil group are configured to generate an electromagnetic field in a region of interest. According to various embodiments, the permanent magnet has an aperture passing through its center. According to various embodiments, the region of interest is located outside the front surface.

Described herein are compact MRI systems having (i) an open, field-cycling magnet configured to produce and cycle between a first and second non-uniform B0 different from the first non-uniform B0, and (ii) a second component configured to produce a nonlinear spatial encoding gradient. Importantly, the open, field-cycling magnet and the spatial encoding gradients are customized to a specific imaging application. In particular, the second component contains one or several nonlinear DC gradient coils for spatial encoding. It also contains one or several a radiofrequency coils geometrically configured to have a non-planar configuration. Lastly, both the RF coils and DC encoding gradients are tailored specifically to the first non-uniform B0 magnetic field, the second non-uniform B0 magnetic field, or both. Artificial intelligence models trained to read imaging data can be incorporated as a component of the MRI systems. Also described are methods of using the disclosed MRI systems.

Disclosed herein is a magnetic resonance imaging (MRI) coil assembly comprising: a set of one or more quantum sensors and associated set of one or more radio frequency coils respectively, wherein each radio frequency coil of the set of one or more radio frequency coils is configured to perform radio frequency excitation in an object to be imaged for inducing a magnetic resonance signal from the object; wherein each quantum sensor of the set of one or more quantum sensors is configured to receive a signal induced by the magnetic resonance signal in the respective radio frequency coil and provide an optical signal representing the MRI signal through an optical link. The MRI coil assembly comprises an optical signal processing unit that is configured to receive through the optical links the one or more optical signals and to digitize the one or more optical signals.

The invention relates to the technical field of oil and gas field development, in particular to a method for judging nuclear magnetic resonance pore throat radius distribution reasonability. The invention discloses a method for judging the rationality of nuclear magnetic resonance pore throat radius distribution, and the method comprises the steps: taking a high-pressure mercury injection pore throat radius cumulative volume ratio distribution curve as a left boundary line, and taking a converted nuclear magnetic resonance pore throat radius cumulative volume ratio distribution curve as a right boundary line; if the target nuclear magnetic resonance pore throat radius cumulative volume proportion distribution curve obtained by other methods is located between the left boundary line and the right boundary line, the target nuclear magnetic resonance pore throat radius cumulative volume proportion distribution curve is reasonable, otherwise, the target nuclear magnetic resonance pore throat radius cumulative volume proportion distribution curve is not reasonable; the method has an important value for oil and gas reservoir evaluation.

The invention provides a method and a system for determining diamond nitrogen vacancy color center intrinsic transverse relaxation time. The method comprises the following steps: acquiring a transverse relaxation time calibration value of a standard nitrogen vacancy color center diamond sample; respectively measuring the first transverse relaxation time and the second transverse relaxation time of the standard nitrogen vacancy color center diamond sample and the nitrogen vacancy color center diamond sample to be detected under the action of the non-uniform external magnetic field on the detection platform; according to the transverse relaxation time calibration value and the first transverse relaxation time, calculating the transverse relaxation time deviation of the standard nitrogen vacancy color center diamond sample under the action of the non-uniform external magnetic field; and according to the transverse relaxation time deviation and the second transverse relaxation time, calculating the intrinsic transverse relaxation time of the nitrogen vacancy color center diamond sample to be measured. According to the method and the system, an ultrahigh-uniformity static magnetic field environment with extremely high cost is not needed, the detection method is high in robustness, and the calibration accuracy of the to-be-detected sample in a complex or non-ideal experimental environment can be remarkably improved.

A method to assess presence of tumor tissue in a biological specimen resected during surgery / biopsy using the Field Cycling Relaxometry technique, system for carrying out the method of corresponding computer program product for controlling the system.

A method is provided for increasing a measurand, said measurand being associated with the exposure of probe spins to a sample magnetic field generated by precessing sample spins. The method comprises providing a solid comprising spin systems localized therein, said spin systems providing the probe spins, said probe spins having an average position. The method comprises providing a sample in a sample region, the sample comprising said sample spins, and said sample having a sample average position. The method comprises applying a static magnetic field to the sample region, the static magnetic field having a component being spatially homogeneous in the sample region, said component acting along a first direction, said static magnetic field causing the sample spins to precess. A distance between the sample average position and the average position of the probe spins does not exceed one millimeter, such that the probe spins are exposed to a sample magnetic field generated by the precessing sample spins. The method comprises, while the static magnetic field is being applied to the sample region: applying a pulsed magnetic field to the sample region, the pulsed magnetic field having a component along the first direction, wherein a gradient of said component of the pulsed magnetic field has a component perpendicular to at least one of the first direction and a relative sample position, wherein the relative sample position refers to a vector difference resulting from subtracting the average position of the probe spins from the sample average position. The method further comprises, while the static magnetic field is being applied to the sample region: measuring a measurand that is associated with occupations of quantum mechanical states of the probe spins. Said gradient has a magnitude, said magnitude referring to a time integral of said component of the gradient over a temporal period of the pulsed magnetic field. The method is characterized in that the magnitude is such that the measurand is increased by at least 25% over a reference measurement of the measurand, the reference measurement being performed like said measurement except for the applying of the pulsed magnetic field, wherein the pulsed magnetic field is not applied in the reference measurement.

A Two-Field-NMR spectrometer (10) for performing field-cycling NMR relaxometry experiments comprising a high field superconducting NMR magnet system (11') for generating a homogenous magnetic field parallel to a z-axis in a central region of the spectrometer for polarization of an NMR sample (12) and for detection of NMR signals; a low field magnet system (11") generating a variable homogenous magnetic field; a magnetic tunnel (14) connecting the center of the high field magnet system with the low field magnet system; and a shuttle system (13) designed for shuttling the NMR sample between the high field and the low field magnet system is characterized in that the magnetic tunnel is provided with a further magnet system (14'); and that the high field magnet system, the magnetic tunnel and the low field magnet system are arranged coaxially about the z-axis along a bore (15) of the high field magnet system. This allows fast field-cycling over a wide range of magnetic fields with very homogeneous low fields, excellent resolution of detected spectra at high fields, high detection sensitivity and preserving as much as possible the lifetime of manipulated spins.

A low field MRI instrumental system includes: an electromagnetic Radio Frequency antenna to emit RF pulses for inducing Electron Paramagnetic Resonance; an electromagnetic Low Frequency antenna for measurements, to emit LF pulses for inducing Nuclear Magnetic Resonance, respectively to receive LF signal produce by NMR; a gradient generator, to create a gradient in a static magnetic field generated during measurements; a high field generator to generate a strong pre-polarization magnetic field for magnetic pre-polarization; and, a control / command unit. This low field MRI instrumental system further includes a low field unit to generate a low static magnetic field whose direction is adjustable along the three directions X, Y and Z of a fixed reference frame associated with the low field MRI instrumental system.

The present invention discloses a method and device for automatically adjusting the FOV applicable to nuclear magnetic resonance scanning. The spatial position monitoring module monitors the displacement and azimuth change of the object to be scanned in the scanning space, and converts the displacement and azimuth change information into parameters and then feeds them back to the sequence scanning control system in the FPGA. The sequence scanning control system calculates the scanning correction parameters according to the displacement and azimuth change parameters, and then superimposes them on the original scanning parameters for parameter modification or logical correction, so as to realize the automatic adjustment of the FOV (Field Of View) of the object to be scanned, avoid the imaging interval deviating from the part of interest due to the position change of the object to be scanned, and can well solve some actual scanning problems, such as the problem of position offset of the living body during long-time scanning of the living body, or the problem of deviation between the placement position of the object to be scanned and the predetermined reference position when the object to be scanned is transported by a conveyor belt. In these cases, there is no need to readjust the position of the object to be scanned, and the scanning FOV can be directly adjusted automatically.

The utility model relates to the technical field of aluminum alloy die castings, and discloses an aluminum alloy die casting for nuclear magnetic resonance equipment, which comprises a shell, the heat dissipation holes are formed in the front surface of the shell; the cover body I is arranged on the front surface of the shell; the dust removal mechanism is arranged in the first cover body and comprises a motor, a connecting shaft rod, a lead screw, a moving plate, a brush handle and a pipeline, the motor is fixedly installed on the left side of the inner wall of the first cover body, the connecting shaft rod is fixedly installed at the output end of the motor, and the lead screw is fixedly installed at one end of the connecting shaft rod; the motor is started to drive the lead screw to rotate, the lead screw drives the movable plate to move left and right, the movable plate drives the brush handle to sweep dust attached to the heat dissipation holes, meanwhile, the air pump is started, the dust suction head sucks the swept dust, sweeping and suction are conducted synchronously, and the dust cleaning effect is improved; and the heat dissipation holes keep a good heat dissipation effect.

The invention discloses a passive shimming method, system and device of a permanent magnet type magnetic resonance imaging system, and belongs to the field of magnetic resonance imaging, and the method comprises the steps: measuring an initial magnetic field, and carrying out the harmonic analysis, and obtaining an initial harmonic coefficient; obtaining gasket parameters to enable the nonlinear magnetization correction analysis model to calculate the gasket magnetization intensity of each gasket through the hysteresis model, converting the gasket magnetization intensity into equivalent surface current density through the equivalent surface current model, and performing integral solution on the equivalent surface current density under a cylindrical coordinate system to obtain the gasket magnetization intensity. Obtaining the magnetic vector potential and the magnetic field of each gasket, and carrying out harmonic analysis to obtain a gasket harmonic coefficient; in the passive shimming optimization model, the magnetization thickness function is iteratively updated to obtain a laying scheme when the total weight of the gasket is minimum, and the gasket is laid according to the laying scheme to realize passive shimming, so that higher field uniformity can be realized, the optimization efficiency is improved, and the consumption of the gasket is reduced.

An apparatus is provided for on-line detection of magnetic resonance signals from a target in a mineral slurry. The apparatus comprises (i) an electrically conductive housing, (ii) an electrically non-conducting (ENC) pipe to enable throughput of a mineral slurry and configured to pass through the electrically conductive housing, (iii) a first primary coil configured to encircle a section of the ENC pipe within the housing, the or each primary coil defining a measurement zone, (iv) a capacitor unit coupled to a terminal of the or each respective primary coil, where a value of each capacitor unit value is selectable so that a primary coil series resonance is formed close to the value of the magnetic resonance frequency of the target, (v) an RF transmitter operable to transmit a signal to one or more drive coil electrical networks, where an operating frequency of the RF transmitter is set approximately equal to the magnetic resonance frequency of the target, (vi) at least a first drive coil and an associated drive coil electrical network, where the number of drive coils equals the number of primary coils, and where each drive coil and associated drive coil electrical network is positioned relative to a single primary coil to magnetically couple said drive coil to said primary coil, (vii) an impedance monitor coupled to each drive coil electrical network and operable to measure a complex input impedance of said drive coil electrical network; and (viii) an RF receiver adapted to receive from the first or each drive coil electrical network, magnetic resonance signals from the target, the RF receiver forming an output signal of detected signals.

The present invention discloses a nuclear magnetic resonance detection device, belonging to the technical field of improvement of nuclear magnetic resonance detection equipment, including a nuclear magnetic resonance scanning body and a patient bed. The bed frame is slidably arranged on the bed base, and air flow channel components are built in both sides of the bed frame. Two groups of blowing and suction control components are arranged on both sides of the bed base, and the two groups of blowing and suction control components are respectively connected to the two groups of air flow channel components. The air flow channel component includes a high-speed channel and a low-speed channel arranged in parallel. The flow ports of the high-speed channel and the low-speed channel are arranged in contact with the inner wall of the detection cavity, and the high-speed channel is closer to the detection cavity than the low-speed channel. One ends of the high-speed channel and the low-speed channel are respectively communicated with one end of an air equalizing cavity, and the other ends of the two air equalizing cavities are respectively communicated with one end of an air flow conveying pipeline. The blowing and suction control component includes a blowing and suction pump, and the other end of the air flow conveying pipeline is communicated with the blowing and suction pump. The present invention can remove the virus carried by the patient during exhalation, and avoid cross-infection and the spread of infectious diseases during subsequent use.

The invention discloses a low-field NMR relaxation time rapid measurement method, and the method comprises the steps: designing an IR-bSSFP pulse sequence which comprises a 180-degree reversal pulse and an excitation pulse sequence, and enabling the flip angle of a radio frequency excitation pulse in the excitation pulse sequence to be a pseudo-random flip angle; the radio-frequency phases of the adjacent radio-frequency excitation pulses are linearly changed by a fixed phase increment; based on the IR-bSSFP pulse sequence, obtaining a component MRF signal sequence of a measured object, and simulating a magnetization vector evolution process to obtain a dictionary matrix; matching the component MRF signal with a dictionary matrix pattern in combination with a smooth constraint term to obtain corresponding longitudinal relaxation time and transverse relaxation time; the invention also discloses low-field NMR relaxation time rapid measurement equipment, which comprises a pulse sequence construction module, a dictionary generation module and a mode matching module. Multi-parameter information can be obtained through single scanning, the measurement time is remarkably shortened, the experiment complexity is reduced, and the precision and repeatability of a measurement result are improved.

The invention relates to a magnetic resonance imaging system (10) comprising a magnetic field generation unit (13), an image acquisition region (14) and a radiofrequency system including at least one radiofrequency antenna, wherein the radiofrequency system is configured to emit a radiofrequency excitation pulse into the image acquisition region (14) and receive magnetic resonance signals from the image acquisition region (14) and wherein the magnetic field generation unit (13) comprises at least one magnet (17) configured to generate a magnetic field in the image acquisition region (14), a magnet holder (33) configured to carry the at least one magnet (17) and a rotation system (30) configured to position the magnet holder (33) along a rotation trajectory (32).

A power supply assembly of a gradient coil is provided. The power supply assembly of the gradient coil may include a first insulation device(400), wherein the first insulation device(400) is located within a scanning channel(301) of a main magnet (300) and connected to one end of the gradient coil(600), the first insulation device(400) may be arranged with a first conductive unit(401), the conductive unit(401) may be a rigid conductor, a first end of the first conductive unit(401) may be electrically connected with the gradient coil(600) of a magnetic resonance imaging system, and a second endof the first conductive unit(401) may be electrically connected with a cable(100) of the magnetic resonance imaging system.

The application discloses a kind of background field wide-range adjustable ultra-low field nuclear magnetic resonance measuring device, and a kind of background field wide-range adjustable ultra-low field nuclear magnetic resonance measuring method is also disclosed, the present application adopts flat solenoid to realize high background magnetic field requirement and ultra-low ambient magnetic field, flat solenoid can also accommodate more coil and obtain more turns, realize more extensive background field adjustable range;Flat solenoid both ends are stretched outside magnetic shielding module, which can ensure that the magnetic flux line at the end of flat solenoid is connected outside the shielding area, eliminating the problem of background field inhomogeneity generated by ordinary solenoid coil;The present application can eliminate the interference of ambient magnetic field by passive magnetic shielding and active magnetic field compensation, first, the ambient magnetic field is shielded by multiple electromagnetic shielding cylinders, and then the magnetic field opposite to the ambient magnetic field is generated by the shim coil to actively compensate the magnetic field, to offset the interference of ambient magnetic field;The shim coil can also improve the uniformity of the central magnetic field.