329 results about "Nuclear magnetic resonance spectrometer" patented technology

The invention discloses a shale micropore size and fluid distribution analysis method. The shale micropore size and fluid distribution analysis method comprises the following steps that shale gas reservoir rock is collected, and a natural core is manufactured; the relaxation characteristic of hydrogen-contained fluid in core pores is measured through a nuclear magnetic resonance spectrometer, and a relaxation time T2 distribution map of clay water is obtained; the core is processed to obtain a saturated core, and a relaxation time T2 distribution map of saturated fluid and a summation curve are obtained; a T2 distribution map of effective fluid is obtained; a T2 distribution map of irreducible fluid and saturability Swi of bound water are obtained; a T2 distribution map of surplus water and water saturation Sw are obtained; the T2 distribution maps of the fluids are converted into a pore size distribution map, the shale clay deadline and the irreducible fluid deadline are obtained, and then the shale micropore size and fluid distribution are obtained. The nuclear magnetic resonance spectrometer is adopted, the pore size and distribution of the shale and size and distribution positions of water drops in the pores are analyzed quantitatively and qualitatively, and the result is reliable.

A nuclear magnetic resonance apparatus that may be used in connection with a variety of different tools, including a down-hole side-wall coring tool as well as with manufacturing process controllers. In one embodiment, the nuclear magnetic resonance apparatus may include a magnet assembly constructed around a sample chamber. The magnet assembly is constructed and arranged to provide a non-uniform magnetic field having a known magnetic field gradient inside the sample chamber. The use of gradient fields may allow for a more flexible and robust magnet assembly design that may be suitable for a variety of different applications.

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.

An NMR spectrometer comprising an NMR magnet system (27) disposed in a helium tank of a cryostat and an NMR probe head (11) disposed in a room temperature bore of the cryostat, which contains a cooled RF resonator (9) for receiving NMR signals from a sample to be investigated, and a cooled pre-amplifier (10), wherein the NMR probe head (11) is cooled by a common multi-stage compressor-operated refrigerator (2), wherein the refrigerator (2) comprises a cold head and several heat exchangers (5, 6) at different temperature levels, wherein the refrigerator (2) is disposed at a spatial separation from the cryostat in a separate, evacuated and thermally insulated housing (1) and wherein at least one cooling circuit with cooling lines, which are thermally insulated by a transfer line (13, 14) is disposed between the housing (1) containing the heat exchangers (5, 6) and the NMR probe head (11), is characterized in that additional cooling lines to an LN₂ tank (18) or radiation shield (21) disposed in the cryostat and surrounding the helium tank are provided, and the refrigerator (2) also cools the LN₂ tank (18) or the radiation shield (21). The inventive NMR spectrometer comprises a simple and inexpensive device for matching the holding time of LN₂ to that of LHe through cooling the LN₂ tank using the refrigerator provided for cooling the NMR probe head and without great expense.

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 compacted rock gas phase relative permeability measurement device and method. The measurement device comprises a rock core clamp, a confining pressure pump, a variable-volume upstream pressure chamber, a variable-volume downstream pressure chamber, a high-pressure gas source, a control table and a nuclear magnetic resonance spectrometer, an air outlet of a high-pressure air source is connected with an inlet of the variable-volume upstream pressure chamber sequentially through a valve a, a first pressure controller and a valve b, an outlet of the variable-volume downstream pressure chamber is connected with the rock core clamp through a valve c, the rock core clamp is connected with an inlet of the variable-volume downstream pressure chamber through a valve d, an outlet of the variable-volume downstream pressure chamber is connected with a pressure relief opening through a valve f, and the rock core clamp is arranged in a measuring cavity of the nuclear magnetic resonance spectrometer. The invention provides a measurement method based on the measurement device. The measurement device has the advantages that gas relative permeability of compacted rocks can be rapidly and effectively measured.

The invention discloses a method for obtaining nuclear magnetic resonance two-dimensional J-resolved spectroscopy in a non-uniform magnetic field, and relates to a nuclear magnetic resonance spectrometer. The method comprises the steps that a piece of one-dimensional spectroscopy is sampled through a general one-dimensional pulse sequence, the line width of a spectral line is obtained, the basis is provided for spectral width parameter setting, and the line width reflects the magnetic field environment uniformity condition; (2) an intermolecular single-quantum coherent two-dimensional J-resolved spectroscopy pulse sequence which is compiled in advance is led to the nuclear magnetic resonance spectrometer; (3) an intermolecular single-quantum coherent signal selection module, an indirect dimension evolution period t1 module, an indirect dimension evolution period t2 module and a signal sampling period t3 module of the intermolecular single-quantum coherent two-dimensional J-resolved spectroscopy pulse sequence are opened, and experiment parameters of the modules of the intermolecular single-quantum coherent two-dimensional J-resolved spectroscopy pulse sequence are set; (4) the intermolecular single-quantum coherent two-dimensional J-resolved spectroscopy pulse sequence with the experiment parameters set in the step (3) is executed, and data sampling is carried out; (5) after data sampling is accomplished, related data post-processing is carried out to obtain the high-resolution two-dimensional J-resolved spectroscopy free from influence of the non-uniform magnetic field.

The present invention relates to a device capable of producing a high resolution chemical analysis of a sample, such as fluid, based upon nuclear magnetic resonance (NMR) spectroscopy, where the nuclear magnetic polarizations of the sample are generated by sequentially illuminating the sample with a focused beam of light carrying angular orbital angular momentum (OAM) and possibly momentum (spin). Unlike in usual NMR used for magnetic nuclear resonance imaging (MRI) or spectroscopy, the invention does not make use of a strong magnet.

The invention discloses a magnetic-resonance compatible pneumatic puncture surgical robot which comprises a location module, a puncture orientation module and a needle feed module which are sequentially connected, wherein the location module adopts a manner of arranging a shear fork type lift mechanism on an annular guide rail slide block, then arranging an annular guide rail on a rodless air cylinder and a linear guide rail slide block, so that the movable location of a puncture needle in a magnetic-resonance imaging device in the axial direction, the radial direction and the peripheral direction is achieved; the puncture orientation module can adjust and locate the puncture angle of the puncture needle based on being fixed to a rotation shaft through a parallel four-rod RCM mechanism; the needle feed module can achieve automatic control on needle feed and needle withdrawal of the puncture needle in a mode that two friction wheels are pushed by an air cylinder to drive the puncture needle. The magnetic-resonance compatible pneumatic puncture surgical robot is simple in structure, saves space, is safe and reliable, can work in a narrow space and a high-field-intensity magnetic field of a nuclear magnetic resonance spectrometer, is smaller in interference on magnetic resonance imaging and effectively improves the accuracy and the stability of puncture operation.

The invention provides a method for obtaining a high-resolution two-dimensional J decomposition spectrum, and relates to a nuclear magnetic resonance spectroscopy detection method. The method comprises: loading a sample to be detected into a standard nuclear magnetic test tube, and conveying into the detection chamber of a nuclear magnetic resonance spectrometer; sampling the one-dimensional hydrogen spectrum of the sample to be detected, and obtaining the signal peak distribution area and the spectral line width so as to provide the reference for the spectral width parameter setting, wherein the line width value reflects the magnetic field uniformity condition; measuring the pulse width of a radio frequency pulse required by excitation of the sample to be detected; introducing a compiled pulse sequence on the nuclear magnetic resonance spectrometer, opening the heteronuclear intermolecule multiple quantum coherent signal excitation module, the indirect dimensional evolving module, the spin echo fixed delay module and the J modulating fast sampling module of the pulse sequence, and setting the experiment parameters of various modules; skipping the artificial shimming operation process, and directly executing data sampling; and after completing the data sampling, calling data post-processing codes to carry out related data post-processing so as to obtain the high-resolution two-dimensional J decomposition spectrum being not affected by the inhomogeneous magnetic field.

A method for obtaining a nuclear magnetic resonance two-dimension spin echo related spectrum under an uneven magnetic field relates to a nuclear magnetic resonance wave spectrum detection method and comprises the steps of using a normal one-dimension pulse sequence to sample a one-dimension spectrum, obtaining the line width of spectral lines, and providing a basis for spectrum width parameter setting, wherein the line width value also reflects the uniformity condition of a magnetic field; introducing well precompiled two-dimension spin echo related spectrum pulse sequences onto a nuclear magnetic resonance spectrometer; opening a multi-quantum coherent signal selection module, a three-dimension sampled indirect dimension evolution period t1 combination and indirect dimension evolution period t2 combination and an echo delay module among the two-dimension spin echo related spectrum pulse sequences; setting each experiment parameter of the two-dimension spin echo related spectrum pulse sequences; executing the two-dimension spin echo related spectrum pulse sequences, of which the experiment parameters are set, for data sampling; after the data sampling is finished, performing related data postprocessing to obtain the two-dimension spin echo related spectrum uninfluenced by the uneven magnetic field. The method has no need of shimming operation and is simple, convenient and effective.

The invention provides a method for obtaining a high-resolution three-dimensional NMR spectrum under a non-uniform magnetic field, and relates to nuclear magnetic resonance spectrometers. The method comprises the steps that (1) a one-dimensional spectrum is sampled by using a conventional one-dimensional pulse sequence and used for analyzing the condition of the non-uniformity of the magnetic field to obtain the line width of a spectral line and provide a basis for experimental spectral width parameter settings; (2) a precompiled intermolecular zero-quantum-coherence three-dimensional spectrum pulse sequence is guided into a nuclear magnetic resonance spectrometer; (3) an intermolecular zero-quantum-coherence signal selection module, an indirect dimension evolution period t1 module, an indirect dimension evolution period t2 module, an indirect dimension evolution period t3 module and a signal sampling period t4 module of the intermolecular zero-quantum-coherence three-dimensional spectrum pulse sequence are opened, and experiment parameters of all the modules of the pulse sequence are set; (4) the intermolecular zero-quantum-coherence three-dimensional spectrum pulse sequence in the step (3) after experimental parameter setting is executed, and data sampling is performed; (5) after data sampling is completed, relevant data post-processing is performed, so that the high-resolution three-dimensional NMR spectrum free of influence by the non-uniform magnetic field is obtained.

The invention provides a shale pore structure detection method based on nuclear magnetic resonance. The method comprises the steps that a sample is processed into a cylinder; the sample is saturated with water at normal pressure for 12h, and then is taken out; CPMG pulse sequence test is carried out on the sample to acquire a spin-echo-series attenuation signal; the spin-echo-series signal is inversed to acquire a T2 spectrum distribution diagram and the details of each peak; and the T2 spectrum of acquired same sample under water saturation and centrifugation is analyzed in a coordinate system to acquire the change of the volume and quantity of pores of the sample. The shale pore structure is mainly studied in a saturated water state in the prior art of nuclear magnetic resonance, and the problems that the study angle is single and limited; only pore distribution can be studied; and fracture prediction cannot be carried out are solved. The method provided by the invention belongs to the technical field of petroleum exploration and development.

A nuclear magnetic resonance quantitative analysis method for a rock micro-crack damage variable is provided; firstly, a sample is processed, the sample is soaked in distilled water, then nuclear magnetic resonance detection is carried out, CPMG pulse sequence detection is carried out on the sample, a spin echo train attenuated signal is obtained, the spin echo train attenuated signal is subjected to inversion, and a T2 spectrum distribution diagram and a spectral area value are obtained; a corresponding relation of the relaxation time T2 and the pore size r is analyzed; according to a fact that the spectral peak area is proportional to the micro-fracture pore number, a rock damage variable formula characterized by the nuclear magnetic resonance transverse relaxation time T2 spectra is established, and the quantitative analysis method is provided for identification of damage of rock materials.

The invention discloses a nuclear magnetic resonance analyzer and a slide table thereof. The slide table comprises a main frame, a sample support and a driving mechanism, the main frame is provided with a non-magnetic platform, a magnet box of the nuclear magnetic resonance analyzer is placed on the non-magnetic platform, the sample support is fixedly connected onto the non-magnetic platform, a detected sample is placed on the sample support, and the driving mechanism is arranged on the main frame, is connected with the magnet box of the nuclear magnetic resonance analyzer, and is used for driving the magnet box of the nuclear magnetic resonance analyzer to move so as to change the position of the magnet box of the nuclear magnetic resonance analyzer relative to the detected sample. By the aid of the slide table of the nuclear magnetic resonance analyzer, phase positions of a magnet in the nuclear magnetic resonance analyzer and the detected sample can be changed, so that different portions of the sample to be detected is placed in a uniform magnetic field, nuclear magnetic resonance measurement to different portions of the sample to be detected is realized, the size of the sample to be detected is not limited, and the dimension range of detected samples which are in nuclear magnetic resonance measurement is expanded.

The invention provides a method of obtaining a high resolution nuclear magnetic resonance spectrum under a nonuniform magnetic field. The method comprises the steps of firstly applying a radio frequency pulse, rotating a magnetization vector from a Z axis to an XY plane, applying phase coding gradients along two directions, applying a sampling gradient of an echo plane spectrum imaging module on a third direction, collecting nuclear magnetic resonance signals, performing data permutation on the collected signals, and performing Fourier transform on a data matrix obtained by the permutation so as to obtain the nuclear magnetic resonance spectrums corresponding to a series of small voxels. The nuclear magnetic resonance spectrum corresponding to each small voxel is in high resolution; as the nonuniform magnetic field exists, the small voxels are directly projected in an accumulative mode, the obtain spectrums are in low resolution; the offset correction is performed on the spectrums corresponding to the small voxels, accumulative projection is then performed, the high resolution one-dimensional nuclear magnetic resonance spectrum can be obtained, and the obtained high resolution spectrum facilitates chemical analysis in a heterogeneous system.

The invention discloses a method for detecting the adsorption capacity of a solid sample to hydrogen-atom-containing gas. The method comprises the following steps: (1) collecting an adsorption nuclear magnetic resonance signal of the solid sample by using a nuclear magnetic resonance spectrometer; (2) determining the adsorption capacity of the solid sample to the hydrogen-atom-containing gas according to the adsorption nuclear magnetic resonance signal of the solid sample. The method disclosed by the invention is convenient to operate, simple in system, high in precision and low in cost, can be used for measuring the adsorption capacity of the solid sample to the hydrogen-atom-containing gas such as methane, so as to draw an adsorption-desorption curve, and can also be used for measuring contributions of different pores to adsorption/desorption so as to analyze the porosity characteristic of the solid sample. Correspondingly, the invention also provides a system for detecting the adsorption capacity of the solid sample to the hydrogen-atom-containing gas, a method for detecting the porosity of a solid and a method for drawing the adsorption-desorption curve of the solid sample to the hydrogen-atom-containing gas.

The invention discloses a two-dimensional diffusion-ordered nuclear magnetic resonance spectroscopy method used for any magnetic field environments and relates to nuclear magnetic resonance spectroscopy detection methods. The method includes the steps of 1), measuring pi/2 nonselective radiofrequency pulse width and (pi/2) solvent selective radiofrequency pulse width required by sample stimulation; 2), importing a nuclear magnetic resonance pulse sequence on a nuclear magnetic resonance spectrometer; 3), turning on an intermolecular zero-quantum coherence signal selection module, a time-invariant evolution module and a diffusion order module of the nuclear magnetic resonance pulse sequence and setting experiment parameters of all modules; 4), executing data sampling; 5), performing data post-processing to obtain high-resolution two-dimensional diffusion-ordered spectroscopy. The two-dimensional diffusion-ordered nuclear magnetic resonance spectroscopy method used for any magnetic field environments does not need any shimming operation, a sample preprocessing process and any special hardware devices, is simple, convenient and feasible and is applicable to any conventional nuclear magnetic resonance spectrometers.