625 results about "Nuclear magnetic resonance spectroscopy" patented technology

Apparatus, methods, and other embodiments associated with NMR fingerprinting are described. One example NMR apparatus includes an NMR logic configured to repetitively and variably sample a (k, t, E) space associated with an object to acquire a set of NMR signals. Members of the set of NMR signals are associated with different points in the (k, t, E) space. Sampling is performed with t and/or E varying in a non-constant way. The varying parameters may include flip angle, echo time, RF amplitude, and other parameters. The NMR apparatus may also include a signal logic configured to produce an NMR signal evolution from the NMR signals, a matching logic configured to compare a signal evolution to a known, simulated or predicted signal evolution, and a characterization logic configured to characterize a resonant species in the object as a result of the signal evolution comparisons.

The present invention discloses a diffusion edited pulse technique that allows information about a fluid to be extracted, comprising: a) obtaining a fluid sample; b) generating a sequence of magnetic field pulses in the fluid, the sequence comprising an initial magnetic field pulse, a first portion that follows the initial magnetic field pulse, and a second portion that follows the first portion; c) detecting magnetic resonance signals using the second portion of the sequence; d) modifying the first portion of the sequence, and repeating steps (b) and (c); and e) extracting information about the fluid by determining relaxation and diffusion characteristics and their correlation based on the signals detected in steps (c) and (d). Also disclosed is a logging tool equipped with a processor to implement the diffusion edited pulse technique.

The invention relates to a nuclear magnetic resonance ground water detection system with reference coils and a detection method. All-waveform data of nuclear magnetic resonance signals in a transmitting/receiving coil and noise signals in the reference coils are synchronously acquired through a plurality of paths of A/D acquiring units; the distribution of optimal positions and quantity of the reference coils is realized through calculating the maximum correlation of the noise signals and the nuclear magnetic resonance signals, which are acquired by the reference coils; and under the condition of unknown signal and noise statistical properties, noise in the nuclear magnetic resonance signals obtained by the transmitting/receiving coil is maximally offset by adopting a variable step adaptive algorithm, the nuclear magnetic resonance signals are extracted under the interference of multi-field source complex strong noise, thus the problems of multiple interferences of nuclear magnetic resonance detection near villages and in neighboring regions of cities and difficulty of separating multiple kinds of interference noise data are effectively solved, the interference resistance of instruments is improved, and a reliable detection device and method are provided for searching underground water near villages and in neighboring regions of cities.

The invention provides nuclear magnetic resonance equipment realizing improved sensitivity of a probe for receiving a free induction decay (FID) signal in nuclear magnetic resonance (NMR) spectroscopy in a high frequency band of 600 MHz or higher. By manufacturing a solenoid coil of a higher filling factor by using a superconductor of extremely low resistance to high frequency current, sensitivity is increased. A superconducting thin film made of magnesium diboride (MgB₂) formed on a donut plate-type substrate is disposed so that the film surface becomes parallel with the uniform magnetic field. The object is realized by a probe made by a solenoid coil formed by connecting a plurality of coil parts by capacitive coupling via a normal metal lead.

A system and method for automating an appropriate voxel prescription in a uniquely definable region of interest (ROI) in a tissue of a patient is provided, such as for purpose of conducting magnetic resonance spectroscopy (MRS) in the ROI. The dimensions and coordinates of a single three dimensional rectilinear volume (voxel) within a single region of interest (ROI) are automatically identified. This is done, in some embodiments by: (1) applying statistically identified ROI search areas within a field of view (FOV); (2) image processing an MRI image to smooth the background and enhance a particular structure useful to define the ROI; (3) identifying a population of pixels that define the particular structure; (4) performing a statistical analysis of the pixel population to fit a 2D model such as an ellipsoid to the population and subsequently fit a rectilinear shape within the model; (5) repetiting elements (1) through (4) using multiple images that encompass the 3D ROI to create a 3D rectilinear shape; (6) a repetition of elements (1) through (5) for multiple ROIs with a common FOV. A manual interface may also be provided, allowing for override to replace by manual prescription, assistance to identify structures (e.g. clicking on disc levels), or modifying the automated voxel (e.g. modify location, shape, or one or more dimensions).

The inventive subject matter as a whole is an improved transceiver apparatus and system for diagnostic evaluations of living subject, human or animal; and is particularly effective as a clinical tool for the spectroscopic scanning or magnetic resonance imaging of humans suspected of being afflicted with a particular disease, disorder, or pathology. The improved transceiver apparatus is used as an essential component in a computer controlled system suitable for magnetic resonance imaging (“MRI”), or nuclear magnetic resonance spectroscopy (“MRS”), and/or nuclear magnetic resonance spectroscopic imaging (“MRSI”); and the present improvement of these electromagnetic signaling systems will provide far more accurate and precise visual images and accumulated data for the clinician or surgeon, as well as serve as a basis upon which to make a diagnosis and decide upon a mode of therapeutic treatment for that individual.

The present invention provides a novel use of a powdered high saturation flux density soft magnetic material as a NMR probe core material. The probe structural geometry facilitates the use of powdered material, which has a relatively low magnetic permeability.

A laboratory NMR methodology (and corresponding laboratory apparatus) defines a sample volume. The method stores downhole tool data corresponding to a hydrocarbon-bearing sample collected from a given subsurface formation. The downhole tool data includes parameters pertaining to magnetic fields used by a downhole tool during a suite of NMR measurements of the given subsurface formation. The sample is positioned in the sample volume of the laboratory apparatus, which applies a static magnetic field in the sample volume. Furthermore, the laboratory apparatus applies a suite of NMR measurements to the sample volume to thereby determine a property of the sample. The NMR measurements of the suite each include a pulse sequence of oscillating magnetic field in conjunction with a pulsed-mode gradient field. The pulsed-mode gradient field is based on the stored downhole tool data corresponding to the sample. A laboratory NMR methodology for optimizing downhole NMR measurements is also described.

The present invention relates to a silicone microporous zeolite and the synthesis method of the silicone microporous zeolite, used to solve the problem that a frame structure of the microporous zeolite synthesized by the prior technology does not contain the silicone and to provide the microporous zeolite, in which the frame structure contains the silicone. The present invention contains the following mol relation: In the formula of (1/n) Al2O3: SiO2: (m/n) R, n is equal to 5-1000 and m is equal to 0.01-300. R is an alkyl, an alkane alkenyl or a phenyl. A solid nuclear magnetic map of Si29NMR is between -80ppm and +50ppm and includes at least one nuclear magnetic resonance spectral peak of Si29. A diffraction pattern of x-ray has a d-spacing maximum at the position of 11.14 plus or minus 0.05, 9.99 plus or minus 0.05, 9.74 plus or minus 0.05, 6.36 plus or minus 0.05, 5.99 plus or minus 0.05, 5.70 plus or minus 0.05, 5.57 plus or minus 0.05, 4.98 plus or minus 0.05, 4.26 plus or minus 0.05, 3.83 plus or minus 0.05, 3.75 plus or minus 0.05, 3.72 plus or minus 0.05, 3.65 plus or minus 0.05, 3.44 plus or minus 0.05, 3.32 plus or minus 0.05 angstrom and 3.05 plus or minus 0.05 angstrom. The microporous zeolite can serve as a sorbent or an activator component used in the transformation of the organic compounds.

The invention relates to an inversion method of nuclear magnetic resonance two-dimensional spectrum. The method includes firstly, extracting and estimating noise, namely extracting noise in CPMG (Carr-Purcell-Meiboom-Gill) echo string of acquired data and estimating standard deviation of the noise; secondly, compressing data, namely generating an inversion kernel and performing truncated singular value decomposition and reconstruction by sequence of a nuclear matrix to complete data compression; and thirdly, fitting the data, namely subjecting fitting problem of the compressed data to regularization, performing iterative solution to regularization factors and inversion spectrum by newton method with non-exact one-dimensional search so as to obtain the inversion spectrum. Execution efficiency of two-dimensional inversion algorithm and resolution of two-dimensional spectrum are increased greatly, and the inversion method is well robust.

The present invention discloses a method and apparatus to make a nuclear magnetic resonance measurement on a flowing fluid using varied wait times. In one method, NMR measurements are made by: a) flowing the fluid through a static magnetic field; b) applying a group of oscillating magnetic field pulses to the flowing fluid, wherein the group of pulses is comprised of an initial pulse and one or more refocusing pulses; c) detecting magnetic resonance signals from the flowing fluid; d) after a wait time, repeating (b) and (c) one or more times, wherein at least two of the repetitions have varied wait times; and e) analyzing the detected magnetic resonance signals to extract information about the flowing fluid. Further, varied wait time measurements may be useful in determining the flow rate of the sample.

The present invention has an object to provide a nuclear magnetic resonance imaging apparatus or the like that avoids a region with zero sensitivity of an optical magnetometer and allows imaging by strong magnetic resonance when a common magnetic field is used as a bias field of an optical magnetometer and as a magnetostatic field to be applied to a sample. When a direction of a magnetostatic field application unit applying a magnetostatic field to a sample is a z direction, alkali metal cell of a scalar magnetometer is arranged so as not to overlap a region to be imaged in a z direction, and so as not to intersect the region to be imaged in an in-plane direction perpendicular to the z direction.

A method for homogenizing a static magnetic field with a magnetic field distribution B0(r) for nuclear magnetic resonance spectroscopy by adjusting the currents C_i through the shim coils, thus creating spatial field distributions C_i·S_i(r), where r stands for one, two, or three of the spatial dimensions x, y, and z, and said magnetic field distribution B0(r) has only a field component along z, in a working volume of a magnetic resonance apparatus with one or more radio frequency (=RF) coils (5) for inducing RF pulses and receiving RF signals within a working volume, said RF coils having a spatial sensitivity distribution of magnitudes B1_k(r), and with shim coils (6) for homogenizing the magnetic field within the working volume, said shim coils (6) being characterized by their magnetic field distributions per unit current S_i(r) and having components only along z, includes the following steps:

• • (a) Mapping the magnetic field distribution B0(r) of the main magnetic field,
  • (b) calculating a simulated spectrum I_S(f) based on the sum of the magnetic field distribution B0(r) and the additional field distributions C_i·S_i(r) generated by the shim coils (6), and on the sensitivity distributions B1_k(r) of the RF coils(5),
  • (c) optimising a quality criterion derived from the simulated spectrum I_S(f) by using an optimisation procedure within a search range with the shim currents C_i as a set of parameters, whereby for each new set of parameter values step (b) has to be repeated,
  • (d) realising the found optimum of the quality criterion of step (c) by generating the associated target field distribution B0_T(r).

In this way a direct one-to-one link is obtained between a set of shim currents and the associated NMR spectrum The quality of the desired NMR spectra can be improved with this method.

The invention provides a method for measuring alkali metal atomic polarizability of a nuclear magnetic resonance gyro in real time and belongs to the field of atomic physics. The method includes: measuring alkali metal atomic densities of an atomic pool at different temperatures, measuring atomic nuclear magnetic resonance frequency of inert gas caused by polarization of alkali metal atoms, and thus acquiring polarizability of the alkali metal atoms in the atomic pool without changing the optical path structure of the nuclear magnetic resonance gyro and the magnetic field environment; building a three-dimensional model of changes in nuclear magnetic resonance frequency of the inert gas in the atomic pool along with temperature and the alkali metal atomic polarizability, measuring the frequency shift of atomic NMR (nuclear magnetic resonance) of the inert gas at any temperature point while the nuclear magnetic resonance frequency normally runs, and thus calculating the polarizability of the alkali metal atoms in the atomic pool in real time. The method has the advantages that the method is simple, no influence is caused to the optical path structure of the nuclear magnetic resonance gyro and the method is of great significance to improving the performance of the nuclear magnetic resonance gyro.

The invention discloses a shale gas reservoir pore structure quantitative calculation method based on nuclear magnetic resonance. The shale gas reservoir pore structure quantitative calculation methodcomprises the following steps: collecting cores; drilling parallel samples, carrying out oil and water self-adsorption nuclear magnetic resonance experiment measurement; contrastively analyzing the difference of a parallel sample oil and water nuclear magnetic resonance T2 spectrum, and determining the distribution of different wetting pore types on the nuclear magnetic resonance T2 spectrum; obtaining a shale gas reservoir full-pore distribution curve according to high-pressure pressurized mercury, nitrogen adsorption and carbon dioxide adsorption; furthermore, obtaining an intersection plate of pore diameters and corresponding T2 time; and according to the intersection plate of different pore types of pore diameters and corresponding T2 time, establishing a quantitative calculation model of the pore diameters according to the pore types. The method has the advantages that a shale gas reservoir pore full-pore distribution curve can be quantitatively calculated through the technology;simultaneously, the nuclear magnetism measurement is quick, simple and loss-free, and is higher in practicability by compared with high-pressure pressurized mercury, nitrogen adsorption and carbon dioxide adsorption; and compared with a conventional method, the calculation result is more accurate.

The invention discloses a nuclear magnetic resonance (NMR) device based on a laser atomic magnetometer, and the NMR device comprises a cesium atom vapor bubble, a magnetic shielding bushing which is sleeved on the cesium atom vapor bubble, three groups of Helmholtz coils which are arranged inside the magnetic shielding bushing, a polarization device which is used for polarizing cesium atoms inside the cesium atom vapor bubble, a laser transmitting device which is used for transmitting detection laser to the cesium atom vapor bubble, a detection device which is used for detecting an NMR signal of the detection laser penetrating the cesium atom vapor bubble and a pneumatic sample feeding device which is used for pre-polarizing a sample to be detected and can place the pre-polarized sample on the cesium atom vapor bubble. The invention also discloses a measurement method of an NMR based on the laser atomic magnetometer. The device and the method are high in detection sensitivity, free from needing low-temperature refrigeration, low in running cost and lower in working temperature.

The invention relates to a rock core displacement effect visual evaluation method. The distribution characteristic and effect of a solution A for displacing another solution B in the rock core are determined by using specific rock core nuclear magnetic resonance equipment, wherein the solution A and the solution B need to be selected from different groups, and are significantly different in relaxation time. The method comprises the following specific steps of: placing a rock core in a rubber tube, thermosetting, placing into an anti-magnetic holder, and placing into a nuclear magnetic resonance test coil; loading the solutions A and B into a solution container; starting nuclear magnetic resonance imaging MRI and rock core application as well as displacement software, and inputting data of the rock core and a displacement solution; adjusting the flow rate and the pressure difference between annular pressure and displacement pressure, starting a pump to displace the solution A, and reversing the process to displace the solution B when only the solution A flows from the outlet; determining and recording 2D images and T2 spectra of the rock core and fluid at different moments when the solution A is displaced by the solution B, and stopping displacement when the 2D images and T2 spectra have no changes; and processing the data to obtain the distribution cloud images of the fluid at different moments.

Disclosed is a non-lineal statistical independent component (ICA) analysis methodology for calculating T2 or T1 distributions of nuclear magnetic resonance logs. In one aspect, the invention employs a classical blind source separation (BSS) approach with the input data (T2 or T1 distributions) being considered not only horizontally (in relaxation time units), but also vertically (in depth). The statistical variations are used for separating the principal independent components and their corresponding weighting matrix. The result of such ICA based BSS is an efficient separation of T2 components correlative to the presence of particular conditions (e.g., clay bound water, heavy oil, capillary bound water, free water, mud filtrate (water and oil), and noise). Individual saturation of estimated fluids can be calculated from the weighting matrix generated in accordance with the invention. In accordance with a further feature of the invention, it is contemplated that independent component analysis techniques may be applied to the underlying time domain data prior to its transformation to a T2 distribution. This advantageously results in “de-noising” of the signal, leading to more precise and accurate results following analysis of the T2 distribution.

A biaxially stretched polypropylene film for capacitors which is a film having a thickness of 1.0-8.0 [mu]m obtained by biaxially stretching a cast raw sheet of a crystalline isotactic polypropylene resin. It is characterized by having a weight-average molecular weight (Mw), as determined by gel permeation chromatography, of 250,000-450,000 and a molecular-weight distribution (Mw/Mn) of 4-7 and giving a molecular-weight distribution curve in which the value obtained by subtracting the differential distribution value corresponding to a logarithmic molecular weight of 6 from the differential distribution value corresponding to a logarithmic molecular weight of 4.5 is from 2% to 15%. The film is further characterized by having a mesopentad content, as determined by high-temperature nuclear magnetic resonance spectroscopy, of from 94% to 98%, excluding 98%.