34 results about "Relaxation spectrum" patented technology

The invention discloses an industrial process online prediction model construction method based on self-attention manifold learning, which is suitable for measuring phase or pulse characteristics, and is characterized in that an initial data manifold is constructed on the basis of an information entropy weight theory, and a self-attention mechanism and a residual error correction algorithm are introduced; and synchronous optimization of weight distribution and embedding mapping is realized through loop iteration, so that a self-adaptive multi-entropy weight manifold embedding prediction model capable of deeply mining data time sequence characteristics is constructed. The effectiveness of the method is verified through a preferable embodiment, specifically, the method is applied to processing pulse nuclear magnetic resonance relaxation spectrum data, and real-time and high-precision online prediction of the wax content in a crude oil sample is successfully achieved. According to the method, the prediction precision and robustness are remarkably improved.

The invention discloses a method and a device for determining water blocking damage degrees of different pore sizes of a rock core. Comprising the following steps: acquiring physical property data of a target rock core and simulated formation water; vacuumizing, pressurizing and saturating the target rock core to obtain a saturated water state rock core, and obtaining a first transverse relaxation spectrum and a first longitudinal and transverse relaxation correlation spectrum through nuclear magnetic resonance; performing displacement treatment on the rock core to obtain a water-bound state rock core, and obtaining a second transverse relaxation spectrum and a second longitudinal and transverse relaxation correlation spectrum; determining a pore size range, and establishing a water blocking damage identification chart to define a characteristic interval between bound water and saturated water; carrying out difference operation to obtain a difference spectrum matrix, extracting pore space areas of bound water and saturated water in the matrix, and calculating an area ratio; and determining the water blocking damage degrees of different pore sizes by combining the porosity, the permeability and the ratio. According to the method, the pore scale can be accurately divided, the damage of each scale can be quantified, the development efficiency can be optimized, and a reliable basis is provided for formulating a reservoir unblocking scheme.

The invention discloses an automatic testing and screening method for electronic components, which relates to the technical field of electronic engineering and microelectronics and comprises the following steps: generating a multi-dimensional stress field through a temperature control module, a humidity control module and an electromagnetic interference simulation module; calling a preset extreme working condition combination sequence based on the target application scene of the component; under a dynamic coupling environment, dominant parameters and recessive parameters including a dielectric relaxation spectrum, a carrier mobility transient response and a thermoacoustic emission signal are synchronously collected; inputting the hidden parameter time sequence data into physical failure models including an electrochemical corrosion model and a thermal mechanical fatigue model; dynamically adjusting the passing threshold of the test item according to the model output; the step of applying accelerated degradation excitation to the screened component comprises the following steps of: circulating a set temperature for a set number of times; applying a bias voltage-temperature stress; and repeating the step S2 to monitor the implicit parameter drift amount, and eliminating the device with out-of-tolerance drift. The device guarantee is provided for the fields of new energy automobiles, aerospace electronics and the like.

The invention belongs to the technical field of oil and gas reservoir engineering and multiphase seepage dynamic monitoring, relates to a characterization method of seepage behaviors of multiphase fluid in a porous medium, and particularly provides a dynamic construction method of a multiphase displacement capillary pressure-saturation relationship based on nuclear magnetic resonance. Comprising the following steps: S1, acquiring a low-field nuclear magnetic resonance relaxation spectrum of a porous medium in a gas-water two-phase displacement process; s2, determining two-phase fluid interfacial tension, a wetting contact angle and a rock surface relaxation rate; s3, determining the dynamic cut-off relaxation time of the displacement stage; s4, calculating equivalent capillary pressure; the residual water saturation is calculated, and the equivalent capillary pressure is the capillary pressure corresponding to the current displacement stage and is used for constructing a capillary pressure-saturation curve. According to the method, the capillary pressure change in the porous medium can be obtained only through spectral analysis without a centrifugal or mercury injection experiment.

The invention discloses a rock pore fluid saturation determination method and device based on multi-nuclear magnetic resonance, and relates to the technical field of oil-gas exploration. A first nuclear magnetic resonance experiment is carried out through the first element, a second nuclear magnetic resonance experiment is carried out through the second element, the saturated water / saturated oil volume and the pore total volume of the rock sample are determined, and the saturation degree of the rock pore fluid is determined in a multi-nuclear magnetic resonance mode. The problem that oil and water signals in the magnetic resonance relaxation spectrum are overlapped to calculate the oil-water saturation inaccurately is effectively solved, and the oil-water saturation calculation precision is correspondingly improved.

The utility model discloses a nuclear magnetic resonance spectrometer probe for real-time detection of a sample heat-moisture treatment process, which comprises a probe cylinder (1) and a sample bin (2) positioned in the probe cylinder (1), a sample to be tested is accommodated in the sample bin (2), the bottom of the probe cylinder (1) is provided with an airflow leading-in port (3), and the airflow leading-in port (3) is communicated with the probe cylinder (1). And air flow enters the probe cylinder (1) through the air flow inlet (3) and is in contact with a sample to be tested in the sample bin (2). According to the utility model, wet and hot airflow is introduced into the probe of the nuclear magnetic resonance spectrometer, so that on-line monitoring of the change rule of the proton relaxation spectrum of a sample in the processes of thermophysics, thermochemistry and the like under the conditions of specific temperature and humidity can be carried out on the premise of non-destructive pretreatment of the sample.

This application discloses a downhole nuclear magnetic resonance (NMR) inversion method, apparatus, equipment, and storage medium based on pruned Bayesian methods, relating to the field of NMR data processing technology. The method includes: constructing a forward dataset based on fluid relaxation time and acquisition parameters, and adding Gaussian white noise to obtain the inversion input signal; initializing prior parameters, posterior mean, and variance; constructing a kernel matrix based on relaxation time points; constructing a kernel-dictionary matrix using Gaussian functions; updating the fitted echo data and fitting residuals using hierarchical Bayesian methods, thereby updating the prior parameters; updating the posterior mean through evidence maximization and calculating the proportion of each fluid component; pruning the kernel-dictionary matrix according to a preset pruning threshold and proportion, iterating until a termination condition is met, and finally mapping to obtain a two-dimensional NMR relaxation spectrum. This method solves the problem of waiting time and loss of diffusion relaxation dimension information caused by improved logging efficiency, which makes accurate multidimensional NMR logging inversion difficult.

This disclosure provides a nuclear magnetic resonance (NMR) analysis method for establishing the chemical composition and condensed-state structure of fluorine-containing materials and its application. The method includes: placing fluorine-containing materials under different operating conditions in a single-sided NMR spectrometer; under a single-sided inhomogeneous magnetic field environment; presetting parameters for a spin echo pulse sequence; using the spin echo pulse sequence to excite fluorine and hydrogen nuclei in the fluorine-containing material to obtain coupled NMR signals of fluorine and hydrogen nuclei; determining echo peak data from the coupled NMR signals according to the preset parameters; processing the echo peak data according to the structural characteristics of the fluorine-containing material to obtain relaxation spectrum fingerprint data; performing data transformation on the relaxation spectrum fingerprint data to obtain transverse relaxation time data; and establishing a relaxation spectrum fingerprint database and a transverse relaxation time database of the coupling of fluorine and hydrogen nuclei in the fluorine-containing material based on the relaxation spectrum fingerprint data and transverse relaxation time data under different operating conditions.

The invention discloses a method, a system and equipment for determining saturation of liquid in a porous medium. The method for determining the saturation degree of the liquid in the porous medium comprises the following steps: determining the type of the porous medium according to the pore size distribution condition of the porous medium; if the porous medium is a single-scale porous medium, respectively obtaining a first nuclear magnetic resonance relaxation spectrum and a second nuclear magnetic resonance relaxation spectrum of the liquid in the porous medium when the liquid in the porous medium is in a saturated state and an unsaturated state; and obtaining the saturation of the liquid in the porous medium according to the first nuclear magnetic resonance relaxation spectrum, the second nuclear magnetic resonance relaxation spectrum and the bulk phase transverse relaxation time of the liquid. By adopting the method and the device, the liquid saturation condition in the porous medium can be better determined, and the method and the device are further suitable for analyzing the occurrence and transportation process of porous multiphase system fluids with complex pore sizes and phase state distribution conditions.

The present application provides a method, device, equipment, and storage medium for testing the pore size distribution of a core sample. The method includes: obtaining M groups of echo point signals of the core sample under M phase encoding gradients; the M is greater than or equal to the X; according to the M groups of echo point signals, obtaining the echo point signals corresponding to each layer of the core sample; according to the echo point signals corresponding to each layer of the core sample, obtaining the T2 relaxation spectrum corresponding to each layer of the core sample; according to the T2 relaxation spectrum corresponding to each layer of the core sample, obtaining the pore size distribution of each layer of the core sample. The method of the present application can obtain the pore size distribution of different layers of the core sample, making the description of the core sample information more accurate.

The embodiment of the application relates to the technical field of nuclear logging, and discloses a training method of a logging model and a T2 relaxation spectrum determination method in nuclear logging, which comprises the following steps: obtaining a logging signal; intercepting a pure noise segment at the tail of the logging signal to generate real non-Gaussian noise data according to the pure noise segment; generating a pure echo train according to a preset T2 relaxation spectrum; determining a noise scaling coefficient according to the average power of the pure echo train and a preset target signal-to-noise ratio; determining noise adjustment data according to the noise scaling coefficient and the real non-Gaussian noise data, adjusting the pure echo train according to the noise adjustment data to obtain a noisy signal; constructing a training set according to the noisy signal and the preset T2 relaxation spectrum; and training the logging model based on the training set until a training termination condition is reached. The application can more accurately obtain the T2 relaxation spectrum in the logging process.

The application provides a method for predicting movable oil content in rock based on nuclear magnetic relaxation ratio, which comprises the following steps: 1) determining a nuclear magnetic base T2 relaxation spectrum of a core in a dry state and a T2 bulk relaxation parameter of white oil; 2) carrying out a complete saturation experiment on the core by using the white oil, carrying out T2 nuclear magnetic resonance test, and obtaining a T2 relaxation spectrum of the core in a saturated state; 3) subtracting the base signal of the core from the saturated T2 relaxation spectrum to obtain a T2 relaxation spectrum of the white oil in the core, and then obtaining the relationship between the relaxation time and the white oil bulk relaxation fluid ratio and calculating the total amount of the white oil bulk relaxation fluid; 4) centrifuging the obtained saturated core, determining the mass of the core and calculating the centrifugal movable fluid content, and establishing a movable oil content prediction formula based on the nuclear magnetic relaxation ratio. The application has reasonable design, the movable oil content is predicted by calculating the proportion of the nuclear magnetic resonance bulk relaxation signal of the oil in the rock, and the reliability of the nuclear magnetic technology in identifying the fluid distribution of the oil is improved.

The present invention relates to a microscopic modeling method of MRE based on the ECC lattice structure, belonging to the field of microscopic structure mechanism analysis and dynamic mechanical property research of intelligent material MRE. A cubic particle network based on the ECC lattice is proposed, where magnetic particles are located at the junctions and connected to elastic springs. By using Langevin dynamics, the control equations of particle motion are derived to calculate the relaxation spectra related to the motion of particles in parallel and perpendicular directions with respect to the applied magnetic field, so as to determine the storage modulus and loss modulus of MRE. Establishing the motion control equations based on the ECC lattice microstructure overcomes the limitations of the phenomenological model and lays a working foundation for the subsequent research on the dynamic magneto-mechanical characteristics of materials. The present invention can more accurately explain the changes in the dynamic mechanical properties of magnetorheological elastomers (MRE) from the mechanism, and the multifunctional MRE with magneto-control characteristics has great potential in the development of new technologies in various industrial fields such as automotive, aerospace, civil, and biomedical.

The present application belongs to the technical field of electronic ceramic nondestructive testing, and is used to solve the problem that the prior art cannot utilize the phase information in strain response to realize accurate positioning of the early fatigue region of ferroelectric ceramics, and specifically relates to an electronic ceramic product defect identification method based on machine vision, which comprises the following steps: applying an alternating electric field to stimulate the electronic ceramic to be measured, and synchronously collecting the displacement signal of the surface of the electronic ceramic to be measured and the excitation voltage reference signal; performing frequency scanning according to a preset frequency sequence at a preset low electric field amplitude; automatically determining a healthy reference region based on the statistical distribution of the relaxation spectrum feature vectors of all measurement points or a preset region; and taking the relaxation peak frequency of each candidate fatigue point as a test frequency; the present application realizes accurate positioning of the real fatigue region while eliminating the pseudo defects such as surface stains and speckle decorrelation by constructing a two-dimensional feature vector of the effective piezoelectric coefficient and the phase delay under the preset electric field.

The invention provides a method for testing a minimum utilization pore throat of oil and gas modified fluid, and relates to the technical field of oil and gas development, and the method comprises the following steps: carrying out a high-pressure mercury injection experiment on a first rock sample to obtain a quantitative relationship between the mercury injection pressure and the pore throat radius; performing a nuclear magnetic resonance T2 spectrum test on the second rock sample to obtain an original T2 relaxation spectrum; establishing a conversion relation between nuclear magnetic resonance T2 relaxation time and aperture by using high-pressure mercury injection data; applying formation pressure to the second rock sample, carrying out constant-temperature reaction, putting into a centrifugal machine, and applying centrifugal force to simulate a strong driving process; and performing nuclear magnetic resonance T2 spectrum test on the centrifuged second rock sample, and calculating the minimum operating aperture according to the conversion relation. According to the method, the temperature and pressure environment and the strong driving process of reservoir in-situ modification are effectively simulated, the minimum using pore throat of the fluid is obtained through quantitative calculation, the precision of the micro-nano pore diameter section is improved through the conversion relation established through the fractal theory, skeleton signal interference is removed, and the accurate fluid occurrence state change rule is obtained.

The invention provides a shale oil in-situ determination method and device, and the method comprises the steps: obtaining a first plate-shaped sample and a second plate-shaped sample from an oil-containing shale sample, carrying out polishing treatment on the second plate-shaped sample, testing the first plate-shaped sample by adopting a nuclear magnetic resonance relaxation spectrum technology, and determining the shale oil in-situ. Acquiring the content of the retained oil of the first plate-shaped sample in an original state, placing the polished second plate-shaped sample in a field emission scanning electron microscope under a preset target acceleration voltage, and observing and recording the occurrence state of the retained oil in pores of the second plate-shaped sample, and analyzing the content of the shale retention oil and the occurrence state of the shale retention oil in different pores based on the content and the occurrence state of the shale retention oil.

The invention discloses a fracture porosity calculation method and system based on two-dimensional nuclear magnetic resonance logging, and the calculation method comprises the following steps: a, carrying out the logging of a drilling well of a target area, obtaining the logging parameters related to the fracture development degree, and enabling the logging parameters related to the fracture development degree to comprise a two-dimensional nuclear magnetic resonance relaxation spectrum; b, analyzing and testing the core of the target area to obtain parameters related to a pore structure; c, a joint calibration method based on constant-speed mercury injection-rock core nuclear magnetic resonance, a joint calibration method based on casting body sheet-rock core nuclear magnetic resonance and a two-dimensional nuclear magnetic resonance logging response method of a crack centralized development section are used, and a crack-pore signal boundary value alpha is obtained; and step d, intercepting the two-dimensional nuclear magnetic resonance logging relaxation spectrum by using the fracture-pore signal boundary value alpha to obtain the fracture porosity. The method effectively solves the problems of low precision and high uncertainty of conventional logging calculation of the fracture porosity and relativity and multiplicity of solutions of imaging logging calculation of the fracture porosity.

The invention provides a method and a device for quantitatively calculating the total organic carbon content of an oil reservoir and identifying a dessert section of the oil reservoir. The method comprises the following steps: taking a plunger rock sample and parallel samples with the same depth; carrying out T1-T2 two-dimensional nuclear magnetic testing on the sample feeding state and different drying states of the plunger rock sample; determining a distribution range of the organic holes in the target block in the T1-T2 two-dimensional spectrum and a corresponding identification standard; according to the standard, the organic pore volume of all plunger samples in the optimal state two-dimensional nuclear magnetic experiment data is counted, and an empirical equation between the two is determined by combining TOC experiment results of parallel samples; and for two-dimensional nuclear magnetic logging of a new well in a target block, calculating the organic pore volume by adopting the standard, and further calculating the total organic carbon content TOC of the shale oil reservoir by adopting the empirical equation. The curve and a geometric mean curve of a transverse relaxation T2 spectrum of two-dimensional nuclear magnetic logging are comprehensively analyzed, sweet spot sections which are good in oiliness and beneficial to output can be rapidly recognized, and a decision basis is provided for optimization of an oil testing scheme.

The invention discloses a method for testing clay permeability along with temperature change, and relates to the technical field of soil body testing. According to the method, the change of the clay permeability along with the temperature is analyzed through a nuclear magnetic resonance technology, firstly, the initial permeability of a soil sample is measured and subjected to vacuum saturation, and then nuclear magnetic resonance relaxation signals are collected at different constant temperatures of 30-60 DEG C; a quantitative relation between temperature and nuclear magnetic signal intensity is established through a dry fine sand calibration experiment, and a relaxation spectrum signal is converted into water mass. And finally, calculating the permeability of the clay at different temperatures based on the fitting slope of the T2 spectrum logarithmic mean value and the temperature. According to the method, lossless quantitative evaluation of the clay permeability under the influence of the temperature is realized. According to the present invention, the fluidity of the water molecules in the cohesive soil can be determined based on the low-field nuclear magnetic resonance technology, the determination method only needs the determination of the initial permeability without the long-time penetration test after the temperature change every time, and the advantages of rapidness and high efficiency are provided.

The present application relates to the technical field of shale pore and fracture analysis, and particularly relates to a shale in-situ macropore and fracture discrimination method based on nuclear magnetic resonance-mercury injection. The shale sample in an in-situ state is first obtained; then, two-dimensional nuclear magnetic resonance testing is performed on the shale sample, and two-dimensional relaxation spectrum is inverted based on a truncated singular value decomposition method; in the inversion process, the value range of the singular value cutoff value is determined based on the two-dimensional data matrix under different signal-to-noise ratios, and the optimal cutoff value is determined through global optimization; then, high-pressure mercury injection testing is performed on the shale sample, and finally, the macropore and fracture region in the shale sample is determined by comprehensively considering the high-pressure mercury injection testing result and the two-dimensional relaxation spectrum. The present application determines the value range of the singular value cutoff value based on the nuclear magnetic resonance testing result under different signal-to-noise ratios, and determines the optimal cutoff value through global optimization, so as to improve the inversion effect, obtain more reliable two-dimensional relaxation spectrum, and then comprehensively discriminate the macropore and fracture by combining the testing results of nuclear magnetic resonance-mercury injection, thereby improving the discrimination accuracy.

The invention provides a nuclear magnetic resonance analysis method for establishing a fluorine-containing material chemical component and a condensed state structure and application thereof.The method comprises the steps that fluorine-containing materials under different working conditions are placed in a unilateral nuclear magnetic resonance spectrometer, in a unilateral non-uniform magnetic field environment, parameters of a spin echo pulse sequence are preset, and the parameters of the spin echo pulse sequence are calculated; exciting a fluorine atomic nucleus and a hydrogen atomic nucleus in the fluorine-containing material by using the spin echo pulse sequence to obtain a coupled nuclear magnetic resonance signal of the fluorine atomic nucleus and the hydrogen atomic nucleus; determining echo peak point data from the coupled nuclear magnetic resonance signals according to preset parameters; performing data processing on the echo peak point data according to the structural characteristics of the fluorine-containing material to obtain relaxation spectrum fingerprint data; performing data transformation on the relaxation spectrum fingerprint data to obtain transverse relaxation time data; and based on the relaxation spectrum fingerprint data and the transverse relaxation time data under different working conditions, establishing a relaxation spectrum fingerprint database and a transverse relaxation time database with fluorine nuclei and hydrogen nuclei coupled in the fluorine-containing material.

The application relates to a nuclear magnetic resonance detection method and system for in-situ characterization of coal pore structure. The method synchronously collects nuclear magnetic transverse relaxation spectrum, two-dimensional spectrum and carbon dioxide / nitrogen adsorption isotherm of a coal sample in a raw state; micro-mesopore distribution and hysteresis ring type are obtained through adsorption; pore morphology is determined by combining a Bayesian classifier with relaxation two-dimensional spectrum and hysteresis ring, and an initial geometric factor is assigned; adsorption and relaxation peaks are matched, and a surface relaxation rate function is calibrated by combining a morphology factor; throat radius is obtained from desorption jump, and a dynamic geometric factor is obtained through convergence iteration of throat-to-pore ratio; finally, the factor and the relaxation rate function are used to convert pore diameter, and full-scale pore structure is obtained by splicing micropore distribution. The scheme eliminates the damage of pretreatment such as mercury injection to the pores of the coal sample in a raw state, eliminates the systematic deviation of a fixed shape factor through automatic identification of morphology and dynamic correction of a geometric factor, solves the ink bottle pore quantification problem, and realizes accurate characterization of full-scale porosity and specific surface area under in-situ conditions.

The invention relates to the technical field of permeability improvement of low-permeability coal seams, in particular to a method for measuring the degree of superheated steam penetrating through a coal body through a low-field nuclear magnetic resonance technology, which comprises the following steps: preparing a standard coal sample subjected to water saturation, drying and superheated steam treatment, and measuring the transverse relaxation spectrum of the standard coal sample by adopting a low-field nuclear magnetic resonance spectrometer; calculating the integral area of the transverse relaxation spectrum and constructing a penetration coefficient K; according to the method, lossless, quantitative and refined evaluation is realized, and a reasonable basis is provided for parameter optimization of a superheated steam anti-reflection process and coal type applicability judgment.

The invention discloses a method, a system and equipment for determining a migration rule of fluid in a porous medium. The method for determining the migration rule of the fluid in the porous medium comprises the following steps: obtaining the porous medium, and measuring to obtain a nuclear magnetic resonance relaxation spectrum of the porous medium; the quantitative relation between the saturation degree of the liquid in the pores and the nuclear magnetic resonance relaxation spectrum under the corresponding liquid state is obtained, and the quantitative relation is determined according to the nuclear magnetic resonance relaxation spectrum of the liquid under the different liquid saturation degrees and the corresponding liquid saturation degrees of the micro-model of the porous structure; and according to the nuclear magnetic resonance relaxation spectrum of the porous medium and the quantitative relationship, determining the occurrence state of the fluid in the porous medium and the fluid migration law. By adopting the method and the device, the occurrence state of the fluid in the porous pores can be accurately obtained, and then important guiding significance is brought for obtaining the fluid migration rule in a porous multiphase system.

The present invention discloses a method and apparatus for determining rock pore fluid saturation based on multi-nuclear magnetic resonance (MNMR), relating to the field of oil and gas exploration technology. By conducting a first NMR experiment using a first element and a second NMR experiment using a second element, the water-saturated / oil-saturated volume and total pore volume of a rock sample are determined. Determining the saturation of rock pore fluid using MMR effectively avoids the inaccurate calculation of oil-water saturation due to overlapping oil and water signals in a magnetic resonance relaxation spectrum, thereby improving the accuracy of oil-water saturation calculations.

The invention provides a method for predicting rock movable oil content based on a nuclear magnet relaxation ratio. The method comprises the following steps: 1) measuring a rock core nuclear magnetic substrate T2 relaxation spectrum in a dry state and a T2 body relaxation parameter of white oil; 2) carrying out a complete saturation experiment on the rock core by using white oil, and carrying out a T2 nuclear magnetic resonance test to obtain a T2 relaxation spectrum of the rock core in a saturated state; 3) deducting a base signal from the saturated T2 relaxation spectrum of the rock core to obtain a T2 relaxation spectrum of white oil in the rock core, solving a relationship between relaxation time and a relaxation fluid proportion of the white oil body, and calculating the total amount of the relaxation fluid of the white oil body; and 4) centrifuging the obtained saturated rock core, measuring the mass of the rock core, calculating the centrifugal movable fluid content, and establishing a rock movable oil content prediction formula based on the nuclear magnet relaxation ratio. The method is reasonable in conception, the movable oil content is predicted by calculating the proportion of the relaxation signal of the nuclear magnetic resonance body in the rock, and the reliability of the nuclear magnetic technology in identifying the fluid distribution of the oil is improved.

The invention relates to the technical field of shale aperture analysis, in particular to a shale in-situ large aperture distinguishing method based on nuclear magnetism-mercury injection combination. The method comprises the following steps: firstly, acquiring a shale sample in an in-situ state; then performing two-dimensional nuclear magnetic resonance testing on the shale sample, and inverting a two-dimensional relaxation spectrum based on a truncated singular value decomposition method; in an inversion process, determining a value range of a singular value cut-off value based on the two-dimensional data matrix under different signal-to-noise ratios, and performing global optimization to determine an optimal cut-off value; and then performing high-pressure mercury injection test on the shale sample, and finally determining a large aperture area in the shale sample by integrating a high-pressure mercury injection test result and the two-dimensional relaxation spectrum. According to the method, the value range of the singular value cut-off value is determined based on the nuclear magnetic resonance test results under different signal-to-noise ratios, the optimal cut-off value is determined through global optimization, the inversion effect is improved, the more reliable two-dimensional relaxation spectrum is obtained, then the large aperture is comprehensively judged by combining the nuclear magnetic resonance-mercury injection test results, and the judgment accuracy is improved.

The application discloses a kind of pore water state evolution characterization method and system in porous medium infiltration process, it is related to porous medium water migration nondestructive testing technical field, including the following steps: obtaining the same porous medium sample in multiple continuous infiltration stages T 2 relaxation spectrum, and the signal weighted logarithmic spectrum center and total signal amount of each T 2 relaxation spectrum;For each infiltration stage, the spectrum center migration factor of the stage is constructed based on the displacement amount of its signal weighted logarithmic spectrum center relative to the signal weighted logarithmic spectrum center of reference stage, the total signal scaling factor is constructed based on the ratio of its total signal amount and the total signal amount of reference stage, the spectrum center migration factor and total signal scaling factor of the same infiltration stage are combined to form the two-factor state coordinates of the stage;According to the order of infiltration stage, each two-factor state coordinates are connected, and the pore water state evolution trajectory is formed.The application effectively overcomes the technical defects that the stage state lacks comparability due to the inability to analyze multiple sources simultaneously.

The application discloses a nuclear magnetic resonance method for in-situ characterization of dispersion of carbon nanotube slurry, and belongs to the technical field of dispersion test of carbon nanotube slurry, and comprises the following steps: testing T2 relaxation spectrum of a solvent in the carbon nanotube slurry to obtain a spectrum peak of the solvent; testing T2 relaxation spectrum of the carbon nanotube slurry to obtain a spectrum peak of the slurry; comparing the number and width of the spectrum peak of the solvent and the spectrum peak of solid particles; if the spectrum peak of the slurry T2 relaxation spectrum is a single peak, and the width variation of the spectrum peak is less than the width variation of the spectrum peak of the solvent, then the dispersion of the slurry is qualified. The method has the advantages of fast detection speed, high measurement accuracy, good repeatability and consistency, and no need for any treatment of the slurry, can realize real-time and in-situ detection of the dispersion of the slurry, and makes up for the shortcomings and deficiencies of traditional slurry dispersion test methods.

The invention provides a rock core displacement method and a method for detecting physical properties of a rock core by using nuclear magnetic resonance and imaging technologies, and relates to the technical field of rock core crude oil exploitation. According to the method, heavy water without H proton signals is used for displacing the rock core, then oil is saturated in the mode that oil displaces the heavy water, at the moment, the occurrence state of the rock core is a water-oil coexistence state, the state of the rock core in the stratum is better met, and the indoor experiment condition is the same as the oilfield exploitation site condition. According to the method provided by the invention, relaxation spectrum detection and imaging detection can be combined in the displacement process, so that the state of the rock core in each time period in the whole displacement process can be precisely monitored, reservoir information can be better known on an oil field site, the recovery efficiency is improved, and technical support is provided for exploration and development of the on-site oil and gas field. Moreover, the method provided by the invention can be suitable for rapidly measuring the unconventional gas and oil storage rock stratum, and has the advantages of rapidness, accuracy and no damage detection.