5534 results about "NMR - Nuclear magnetic resonance" patented technology

This invention relates generally to NMR systems for in vivo detection of analytes. More particularly, in certain embodiments, the invention relates to systems in which superparamagnetic nanoparticles are exposed to a magnetic field and radio frequency (RF) excitation at or near the Larmor frequency, such that the aggregation and/or disaggregation of the nanoparticles caused by the presence and/or concentration of a given analyte in a biological fluid is detected in vivo from a monitored RF echo response.

The invention is directed to multiply-substituted fullerene derivatives of novel configurations, and methods for their preparation and use. The methods involve the combinatorial synthesis of a library of fullerene derivatives and comprises the steps of forming a mixture of fullerene derivatives by reacting the Cn fullerene with two or more reactive precursor compounds, and removing the unreacted compounds to yield the fullerene derivatives having the desired activity. Methods for the identification and screening of a combinatorial library of fullerenes by 3He-nuclear magnetic resonance and electrospray mass spectrometry to define members with the optimal desired activity are also provided.

This invention pertains to chemometric methods for the analysis of chemical, biochemical, and biological data, for example, spectral data, for example, nuclear magnetic resonance (NMR) spectra, and their applications, including, e.g., classification, diagnosis, prognosis.

A semiconductor light-emitting device member excellent in transparency, light resistance, and heat resistance and capable of sealing a semiconductor light-emitting device without causing cracks and peeling even after a long-time use is provided. Therefore, a semiconductor light-emitting device member that comprises (1) in a solid Si-nuclear magnetic resonance spectrum, at least one peak selected from a group consisting of (i) peaks whose peak top position is in an area of a chemical shift of −40 ppm to 0 ppm inclusive, and whose full width at half maximum is 0.3 ppm to 3.0 ppm inclusive, and (ii) peaks whose peak top position is in an area of the chemical shift of −80 ppm or more and less than −40 ppm, and whose full width at half maximum is 0.3 ppm to 5.0 ppm inclusive, wherein (2) silicon content is 20 weight % or more and (3) silanol content is 0.1 weight % to 10 weight % inclusive is used.

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned de superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

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.

Hot-filament chemical vapor deposition has been used to deposit copolymer thin films consisting of fluorocarbon and siloxane groups. The presence of covalent bonds between the fluorocarbon and organosilicon moieties in the thin film has been confirmed by Infrared, X-ray Photoelectron (XPS) and solid-state ²⁹Si, ¹⁹F, and ¹³C Nuclear Magnetic Resonance (NMR) spectroscopy. The film structure consists of chains with linear and cyclic siloxane groups and CF₂ groups as repeat units.

The invention discloses a method for calculating oil saturation of a reservoir. The method comprises the following steps of: establishing a reservoir oil saturation model including a free fluid porosity phi f, a bound fluid porosity phi b, as well as corresponding macropore bond index mf, micropore bond index mb and micropore bond index characteristic value parameters; measuring a core porosity phi of a selected core sample; carrying out a nuclear magnetic resonance T2 spectrum experiment and an electric petrophysical experiment on the selected core sample to determine the core porosity phi and bound water saturation Swir of the selected core sample, the free fluid porosity phi f and bound fluid porosity phi b, stratum water resistivity Rw of a saturated rock sample, saturated water rock resistivity Ro of each rock sample, and resistivity Rt of each rock under different conditions of water saturation Sw; determining parameters of a reservoir oil saturation model by adopting an optimization data fitting method; establishing a relationship between the core micropore bond index mb and the bound water saturation Swir; classifying reservoir cores according to the bound water saturation; and determining a saturation index n of each type of cores by using the optimization fitting algorithm.

This invention pertains to chemometric methods for the analysis of chemical, biochemical, and biological data, for example, spectral data, for example, nuclear magnetic resonance (NMR) spectra, and their applications, including, e.g., classification, diagnosis, prognosis, etc., especially in the context of bone disorders, e.g., conditions associated with low bone mineral density, e.g., osteoporosis.

An apparatus and method for performing nuclear magnetic resonance (NMR) or magnetic resonance imaging (MRI) on samples in metallic holders and vessels or in proximity to metallic objects is disclosed.

The invention provides a quantitative characterization method of low penetration double-medium sandstone oil reservoir microscopic aperture structure, which comprises the following steps: selecting experiment samples, effectively combining various experiments, distributing samples, processing and analyzing experiment test data, combining macroscopic background and microscopic rock core, and combining static state analysis and dynamic production reality, thereby realizing quantitative characterization of ultra-low penetration double-medium sandstone oil reservoir microscopic aperture structure from qualitative analysis and semi-quantitative evaluation. The invention has the advantages that more comprehensive influence factors and micro crack, aperture throat parameter and nuclear magnetic resonance movable fluid parameter are considered, so the characterization result can better reflect change characteristics of ultra-low penetration double-medium sandstone oil reservoir microscopic aperture structure, which are consistent to the production exploitation real cases of the oil field, thereby effectively avoiding one-sidedness and limitation of single aspect evaluation result.

A carbon dioxide drive nuclear magnetic resonance imaging detection device belongs to the technical field of petroleum engineering and technology. The detection device comprises: a simulation core device which is arranged in a nuclear magnetic resonance imaging device; an injection system which sequentially injects formation water, crude oil and supercritical carbon oxide into the simulation core device; a measurement and control system which is employed to control pressure and temperature of the whole system; the nuclear magnetic resonance imaging device which is employed to detect and perform quantitative analysis on an image to be tested to obtain voidage and permeability of a porous medium, and saturation seepage parameters of the supercritical carbon oxide, the formation water and the crude oil; and an output measuring system which is employed to measure volumes of the carbon dioxide gas, the formation water and the crude oil. The detection device has a design pressure of 0-40MPa and design temperature of 0-180 DEG C, and can simulate experimental studies of different displacement schemes of the supercritical CO2 under a complex petroleum reservoir condition; the simulation core device is made of a brass material, which produces no magnetism, satisfies requirements for high pressure and strength, has a compact structure, can be recycled, is conveniently operated, simple and applicable in an experimentation.

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.

A method for determining a formation fluid property includes acquiring a suite of nuclear magnetic resonance (NMR) measurements of a fluid sample using a pulse sequence that includes pulsed field gradient pulses for encoding diffusion information, wherein each NMR measurement in the suite is acquired with a different value in a parameter in the pulsed field gradient pulses for producing a different diffusion effect, wherein the acquiring is performed in a formation fluid sampling tool in a borehole; inverting the suite of NMR measurements to produce a distribution function that relates diffusion properties of the fluid sample with an NMR property of the fluid sample; and determining the formation fluid property from the distribution function.

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 a compressed sensing theory-based reconstruction method of a magnetic resonance random sampled K space data image. The reconstruction method applies a contourlet conversion and iterative soft thresholding method to realize reconstruction of a magnetic resonance image. The method comprises the following steps: collecting K space data in a magnetic resonance image scanner according to a preset observation matrix phi to generate a measurement value, and keeping y; acquiring y from a coil of the magnetic resonance image scanner, and transmitting y to a computer; and finallyconstructing a same phi, constructing any orthogonal transformation psi, and recovering from y by adopting a compressed sensing theory-based magnetic resonance random sampled K space data image reconstruction method according to reconstruction. According to the method, scanning time is saved, quick imaging is realized, high-quality reliable image information is provided to medical nuclear magnetic resonance imaging detection, and solid theoretical and practical foundation is established for further development and large-scale popularization and application of the medical imaging detection technology.

A method for acquiring an image or spectrum of a subject or object residing within the magnetic field of a magnetic resonance apparatus, comprises the steps of:

• • executing a predetermined pulse sequence for applying gradient magnetic fields and for coupling in electromagnetic excitation pulses to induce nuclear magnetic resonance within the subject or object;
  • detecting an electromagnetic signal resulting from said magnetic resonance; and
  • constructing at least one image or magnetic resonance spectrum of said subject or object from said detected electromagnetic signal.

According to the invention, said coupling in of the electromagnetic excitation pulse and/or said detecting of the electromagnetic signal are carried out substantially by means of travelling electromagnetic waves.