2617results about "Analysis using nuclear magnetic resonance" patented technology

A method for material detection is described. The method may include extracting, from a material database, a resonance frequency for the target material. The method may further include comparing an application type to entries in a scan database. The scan database may store pre-defined scanning patterns and corresponding application types. The method may include extracting, from the scan database, a scan sequence for the application type. Also, the method may include instructing a gimbal to follow positions in the scan sequence. The method may also include transmitting into an environment an RF signal when the gimbal is at the positions in the scan sequence. The method may further include receiving a response signal from the environment. The method may include analyzing the response signal for resonance characteristics that indicate a presence of the target material. Additionally, the method may include generating a haptic feedback when the target material is detected.

The invention relates to a lacustrine facies shale conductive model considering organic matter influence and a saturability evaluation method, and belongs to the technical field of unconventional oil and gas reservoir oiliness evaluation, and the method comprises the following steps: 1) representing fluid information in a shale sample based on a pressure-maintaining closed sample and a two-dimensional nuclear magnetic resonance technology; 2) according to the organic carbon content and the clay content of the shale, dividing the lithology type of the lacustrine facies shale, and analyzing the relation between different lithology resistivity values and the porosity of free water and bound water; 3) selecting a siltstone interlayer sample, and inversely calculating a cementation index and a saturation index of the inorganic pore conductive network; 4) establishing a lacustrine facies shale parallel conductive model, and calibrating rock-electricity parameters according to lithology; 5, a lithology discrimination chart, a TOC prediction model, a bound water content prediction model and an effective porosity calculation model are established, and the oil saturation is explained according to different lithologies in combination with the lacustrine facies shale parallel conduction model.According to the method, accurate shale reservoir fluid information is provided, and a brand new thought is provided for rock electrical parameter calibration.

The invention provides a fusion protein and application thereof in preparation of Brazilian sweet. The fusion protein comprises a tag protein and a Brazilian sweet protein which are connected by a linker; wherein the linker comprises an amino acid sequence as shown in SEQ ID NO: 1, and the amino acid sequence as shown in SEQ ID NO: 1 is directly connected with the Brazilian sweet protein. The invention also provides a preparation method of the Brazilian sweet protein. The preparation method comprises the following steps: treating the fusion protein by using TEV protease and obtaining the Brazilian sweet protein. Large-scale expression of the fusion protein and the brazitame protein is realized by utilizing an escherichia coli expression system, and the obtained brazitame protein can be correctly folded and has high sweetness.

The invention provides a method for intelligently predicting the strength of a filling body by combining color and pore structure characteristics, and relates to the technical field of mine filling, the method comprises the following steps: firstly, selecting a filling material for mine production, making an experimental scheme on the basis of the actual proportion of mine production, and preparing and maintaining the filling body; then obtaining a color characteristic value, a pore structure characteristic value and a uniaxial compressive strength value of the filling body; and processing the color characteristic value, the pore structure characteristic value and the uniaxial compressive strength value, establishing a data set, constructing an initial strength prediction model, and performing evaluation and optimization to obtain an optimal strength prediction model.

The invention relates to the technical field of analysis and detection, in particular to a method for identifying free nucleic acid and nucleic acid wrapped by a carrier based on nuclear magnetic resonance phosphorus spectrums.The method comprises the following steps that 1, the free nucleic acid serves as a contrast, nuclear magnetic resonance phosphorus spectrum detection is conducted, and a nuclear magnetic phosphorus spectrogram of the free nucleic acid is obtained; (2) taking the nucleic acid combined with the carrier as an experimental group, and performing nuclear magnetic resonance phosphorus spectrum detection under the same condition to obtain a phosphorus spectrogram of the experimental group; and (3) comparing the characteristic changes of peak positions, peak shapes, peak heights, peak areas and the like of the experimental group and the control group to identify the free nucleic acid and the nucleic acid wrapped by the carrier. The method has good accuracy, repeatability and stability, can be used for nondestructive testing, and is suitable for analyzing sensitive samples. The method can be used for detecting the binding condition of a carrier and nucleic acid in a nucleic acid drug, predicting the encapsulation efficiency and release rate of the nucleic acid drug, and providing an important analysis tool for opening, production and quality control of the nucleic acid drug.

The invention provides a shale oil reservoir oil content evaluation method, which comprises the following steps: coring a shale sample, and carrying out anhydrous wire cutting processing to obtain a plunger sample and a crushed sample in an original state; respectively carrying out two-dimensional T1-T2 nuclear magnetic resonance testing on the plunger samples in the original state and the oil-water recovery state; according to the T1-T2 nuclear magnetic resonance spectrum, oil signal amplitudes of the plunger sample in an original state and an oil-water recovery state are identified, and a light hydrocarbon recovery coefficient is determined; the crushed sample is subjected to conventional pyrolysis and multi-temperature-order pyrolysis, conventional pyrolysis parameters and multi-temperature-order pyrolysis parameters are obtained, a first equation is established, and the first equation represents the relation between the original state oil content and the conventional pyrolysis parameters; according to the light hydrocarbon recovery coefficient and the first equation, a second equation is established, and the second equation represents the relation between the oil content in the oil-water recovery state and the conventional pyrolysis parameters; and evaluating the oil content of the shale oil reservoir in the oil-water recovery state according to the second equation and the measured conventional pyrolysis parameters.

The invention belongs to the technical field of evaluation, development and research of oil and gas reservoirs, and discloses a T2 cutoff value calculation method based on a saturated nuclear magnetic resonance experiment. The method comprises the following steps: acquiring a saturated / bound water nuclear magnetic resonance T2 spectrum curve of a compact sandstone sample; determining a T2 cut-off value based on a saturated / bound water nuclear magnetic resonance accumulative porosity curve, and recording the T2 cut-off value as T2-Cuff; acquiring a logT2-logphi intersection curve of the saturated nuclear magnetic resonance T2 spectrum, and recording a T2 value corresponding to an inflection point of the curve as T2-Log; and determining a mathematical relationship between the T2-Log and the T2-Cuff, and establishing a T2 cut-off value calculation model based on the saturated nuclear magnetic resonance experiment. According to the method, the T2 cutoff value can be calculated only by performing the nuclear magnetic resonance experiment on the saturated water sample and performing mathematical treatment on the T2 spectrum, and the method has the advantages of being economical, simple, efficient and high in practicability.

The invention discloses a method and a device for testing moisture migration characteristics of frozen soil under low-temperature nuclear magnetic triaxial seepage, and relates to the technical field of frozen soil testing. In order to solve the problems that in the prior art, compatibility control of freezing and seepage cannot be achieved, and whole-process evolution of frozen soil moisture migration characteristics is difficult to dynamically capture, the scheme comprises the following steps that the real confining pressure, axial pressure and seepage speed of the environment where a soil sample is located are simulated; collecting a nuclear magnetic resonance image and an overall and layered T2 spectrum of the soil sample before freezing under the action of seepage; gradually freezing the soil sample based on different temperature gradients, and collecting a nuclear magnetic resonance image and an overall and layered T2 spectrum of the soil sample under the seepage and freezing coupling action in real time; data are collected according to the whole soil sample freezing process, and the evolution law of water migration characteristics in the soil body freezing process is analyzed. According to the invention, the whole-process, visual and nondestructive detection is realized, and the whole-process evolution rule of water migration characteristics such as unfrozen water content and pore cracks in the frozen soil under the seepage and freezing coupling action can be accurately captured.

Embodiments include a system for material detection and identification. The system may include an RF transmit device configured to transmit into an environment an RF signal at a resonance frequency. The system may also include an RF receiver device configured to receive a response signal from the environment. The system may further include a communication device connecting the RF transmit device and the RF receiver device. The communication device may include a control module. The system may include a geolocation device. The control module may be configured to receive geolocation data from the geolocation device, analyze the response signal for resonance characteristics that indicate a presence of a material, and identify the material to a user when the presence of the material is indicated by the resonance characteristics. Methods for material detection and identification are also described. Methods may involve obtaining geolocation data.

The invention discloses a method and system for representing shale oil sample occurrence state based on nuclear magnetic resonance, and relates to the technical field of offshore shale oil exploration, and the method comprises the following steps: respectively obtaining a regular plunger shale sample and an irregular shale sample at the same sampling position in a target stratum; performing a nuclear magnetic resonance experiment on the irregular shale sample to obtain a nuclear magnetic signal of the irregular shale sample, performing inversion to obtain a T2 spectrum of the irregular shale sample, and determining an initial nuclear magnetic porosity; carrying out different equal cutting on the regular plunger shale sample, and sequentially carrying out nuclear magnetic resonance experiments to obtain a target fitting relationship between different core surface areas and nuclear magnetic porosity; and determining a porosity correction coefficient based on the target fitting relationship and the initial nuclear magnetic porosity, and determining the porosity of the irregular shale sample to be measured based on the porosity correction coefficient. According to the method, the technical problem that the fluid occurrence state of the irregular shale sample is difficult to characterize due to scarcity of the shale oil sample on the sea in the prior art is solved.

The invention discloses a high and low temperature control rock-soil nuclear magnetic resonance triaxial apparatus and a use method, the high and low temperature control rock-soil nuclear magnetic resonance triaxial apparatus comprises a high and low temperature control rock-soil nuclear magnetic resonance triaxial apparatus arranged in a low field nuclear magnetic resonance analyzer, the high and low temperature control rock-soil nuclear magnetic resonance triaxial apparatus comprises a temperature control system, a pressure chamber, an axial stress loading device and a data acquisition system, temperature control systems are arranged at the upper and lower ends of the pressure chamber; and an axial stress loading device and a data acquisition system are arranged below the pressure chamber. According to the invention, high and low temperature accurate and stable control can be realized, an in-situ occurrence temperature environment and a real stress state of a soil sample are really simulated, and the material and the size of the device are adaptive to the test requirements of a low-field nuclear magnetic resonance analyzer and the size of a pore cavity; the test research on the macroscopic strength characteristic, the micro-pore structure, the permeability characteristic and the like of the geotechnical material by the temperature can be carried out; while the strength and deformation mechanical property indexes of the sample are obtained, a high-resolution image of internal pore structure evolution and dynamic moisture migration can be captured.

The invention provides a device for simulating the influence of deep fracture on natural hydrogen migration and an evaluation method, and belongs to the technical field of natural gas exploitation, the device comprises a core holder, an overburden pressure tracking pump, a temperature control device, a hydrogen storage tank and a nuclear magnetic device; the core holder is provided with two connecting ends; each connecting end is provided with a pressure gauge; the overburden pressure tracking pump is respectively connected with the two connecting ends; the temperature control device is connected with the core holder; the hydrogen storage tank is respectively communicated with the two connecting ends; a flow density meter is arranged on a communicating pipeline between the hydrogen storage tank and each connecting end; the nuclear magnetic device is used for forming a uniform magnetic field area at the core holder and acquiring nuclear magnetic signals of hydrogen atoms in the loaded sample in the uniform magnetic field; the evaluation method is carried out by adopting the device. According to the device for simulating the influence of the deep fracture on the migration of the natural hydrogen and the evaluation method, the migration mode of the hydrogen in the fractured reservoir can be accurately tracked and determined, and obtained experimental data are more comprehensive and accurate.

The invention discloses a method for evaluating the wettability of shale based on alternate spontaneous imbibition, which comprises the following steps: step (1), obtaining the apparent volume of a to-be-tested sample, then smearing sealant on the periphery of the to-be-tested sample, standing, and entering step (2) after the to-be-tested sample is air-dried; step (2), based on a low-field nuclear magnetic resonance method, calibrating a relation between the mass of the imbibition fluid and a nuclear magnetic semaphore; (3) alternately imbibing dodecane and a 8wt% KCl aqueous solution into the to-be-detected sample treated in the step (1), and monitoring the weight change of imbibition fluid imbibed into the to-be-detected sample by using a two-dimensional nuclear magnetic resonance spectrometer in the alternate imbibition process; (4) determining an oil wet pore volume and a water wet pore volume through a fluid calibration relation; and (5) calculating a main pore wettability index according to the content of the imbibition fluid, and then evaluating the wettability of the shale.

The invention discloses a nuclear magnetic T2 spectrum correction method for a shale reservoir, and relates to the field of object detection, and the nuclear magnetic T2 spectrum correction method for the shale reservoir comprises the following steps: 1, determining the gas logging porosity, saturated water porosity and main mineral components of the shale reservoir; compared with the prior art, the method disclosed by the invention has the beneficial effects that a drying-saturated water-centrifugal two-dimensional nuclear magnetic resonance experiment is carried out, and signals of crystal water, clay bound water and hydroxyl in a sample are preliminarily identified; through inversion of organic matter signals in the dry sample, signals of movable water are further determined; the relation between the difference value among the gas logging porosity, the saturated water porosity and the nuclear magnetic porosity and different mineral contents is discussed, and particularly the remarkable influence of iron-containing minerals on the porosity difference value is discussed; by eliminating the influence of diffusion relaxation caused by the magnetic susceptibility difference, the T2 spectrum correction method based on the mineral magnetic susceptibility is established, and the T2 spectrum accuracy obtained through nuclear magnetic resonance measurement is improved.

The invention relates to a metabolic marker for diagnosing diabetic secondary osteoporosis and application of the metabolic marker, and belongs to the technical field of biological medicine. The method comprises the following steps: firstly, screening out obviously different metabolites between osteoporosis (DOP) and osteoporosis-free groups (DM) in diabetic patients; and secondly, screening out significant difference metabolites between the primary osteoporosis patient and the healthy control group, and excluding the intersection of the two groups of difference metabolites to obtain metabolites which exclude the influence of the primary osteoporosis. Metabolic markers, namely cytosine nucleotide, ketoglutaric acid and triethylamine, are obtained through further screening, and when the three metabolic markers are independently used, AUCgt; the AUC during combined use is 0.99, so that the limitation that the sensitivity of the traditional bone mineral density detection on the osteoporosis recognition in the diabetic population is insufficient is effectively made up.

The invention relates to the technical field of detection equipment, and provides a Cantonese mooncake water activity testing device and method.The Cantonese mooncake water activity testing device comprises a detection box and further comprises an inner testing cylinder, an outer testing cylinder and a water storage tank, the material reserving chamber is formed in the front middle part of the inner measuring cylinder; the placement cavities are formed in the left side and the right side of the interior of the inner measuring cylinder, and the two placement cavities are located on the left portion and the right portion of the material reserving cavity correspondingly; the rotating assembly is installed on the lower portion of the material reserving cavity and used for driving the moon cakes to rotate; the outer fan back plate is mounted at the rear middle part of the material reserving chamber; inner fan polar plates are installed on the inner walls of the left side and the right side of the outer fan back plate, and the outer sides of the two inner fan polar plates are connected with a positive pin and a negative pin of a capacitor through leads respectively. When the mooncake water activity detection device is used, the inner detection cylinder, the material reserving cavity and the inner fan pole plate are used for conducting capacitance water activity detection on the front face and the back face of a mooncake, the electromagnetic wave sensor is used for conducting microwave water activity detection on the side face of the mooncake, and comprehensive water activity detection on the mooncake is achieved through combination of the two.

The invention provides a nuclear magnetic resonance and image intelligent bimodal unfrozen water dynamic identification method and system, and belongs to the technical field of frozen soil engineering and geophysical exploration, and the method comprises the steps: sealing a frozen soil sample in a nuclear magnetic sample tube, and achieving the gradient cooling of the sample in a preset low temperature range through temperature control; scanning by using a nuclear magnetic resonance technology to obtain transverse relaxation time T2 spectrums and nuclear magnetic images of the frozen soil sample at different temperature nodes; after image preprocessing is carried out on the nuclear magnetic image, a temperature-signal intensity curve in the nuclear magnetic image is automatically extracted by utilizing an image recognition technology; carrying out integral calculation on a liquid water signal in the T2 spectrum, and dynamically calculating the content of the unfrozen water at each temperature based on a nuclear magnetic signal intensity formula; according to the method, a pore-fracture co-evolution matrix is constructed, accurate analysis of unfrozen water dynamic and pore evolution in the freezing and thawing process is realized, the method is suitable for hydrothermal coupling characteristic analysis of Qinghai-Tibet soil in a complex freezing and thawing environment, and reliable technical support is provided for stability evaluation of frozen soil engineering.

The invention relates to the technical field of rock sample oil-water saturation determination based on a nuclear magnetic technology, and provides a shale sample oil-water saturation intelligent determination method based on a two-dimensional nuclear magnetic technology, and the method comprises the following steps: collecting volumes, echo signals and signal-to-noise ratios of a preset number of rock samples; marking a target rock sample and a comparison rock sample, and determining a volume influence comprehensive interference degree and a noise amplification coefficient of a target echo signal; obtaining a denoised target echo signal according to the target echo signal, the volume of the rock sample corresponding to the target echo signal and the noise amplification coefficient of the echo signal; according to experiments of rock sample two-dimensional nuclear magnetic oil-water distribution, pore attributes and the like, a two-dimensional nuclear magnetic T1-T2 map is divided into an invalid pore area and an effective pore area of a rock sample corresponding to the two-dimensional nuclear magnetic T1-T2 map and an oil-water distribution area of the effective pore area, a fluid close to reservoir oil-water distribution is adopted to recover a two-dimensional nuclear magnetic spectrum of the rock sample, and the oil-water content corresponding to a nuclear magnetic signal is extracted; and obtaining a rock sample oil-water saturation determination result based on the nuclear magnetic technology.

Disclosed is a microscopic comparison and experimental verification method for the wettability of similar surfactants on coal dust, comprising: collecting a coal sample on site from a mining area and analyzing the coal sample by infrared spectroscopy and nuclear magnetic resonance spectroscopy to obtain information on functional groups and carbon structure of coal molecules; S2: constructing a surfactant-coal molecule electrostatic interaction model and analyzing an orbital energy difference and an electrostatic potential difference between surfactant molecules and coal molecules, etc. S6. The invention provides a simple and effective idea for the selection of surfactants.

The invention discloses a method for characterizing the pore size of the full pore diameter of shale based on combined measurement of a gravimetric method and NMR. The method comprises the following steps: drawing a curve that the pore distribution frequency of a rock sample changes along with the pore diameter; calculating the saturated water porosity of the rock sample based on the weight of the dried rock sample and the weight of the saturated rock sample; based on the saturated water porosity of the rock sample, converting the nuclear magnetic semaphore of the nuclear magnetic resonance T2 spectrum after saturation treatment of the rock sample into a porosity component; based on the porosity component, drawing a change curve of the porosity component and the porosity accumulated value along with the relaxation time T2 after saturation treatment of the rock sample; calculating a space-time conversion coefficient between the nuclear magnetic resonance relaxation time T2 value and the pore size; and based on the space-time conversion coefficient, drawing a full-aperture pore size result graph after saturation treatment of the rock sample on the basis of the change curve of the porosity component and the porosity accumulated value along with the relaxation time T2 after saturation treatment of the rock sample. The phenomenon that the measurement ranges of the pore sizes are overlapped does not exist through multiple simultaneous measurement means, and the obtained full-aperture pore size result is higher in precision.

The invention discloses a shale reservoir crack and cement analysis method based on a nuclear magnetic resonance technology, and relates to the technical field of geological prospecting, and the method comprises the following steps: obtaining a shale reservoir core sample, and cleaning and drying the core sample; the processed rock core sample is placed in a nuclear magnetic resonance spectrometer, measurement parameters are set, nuclear magnetic resonance data are collected, and the collected data comprise transverse relaxation time distribution and longitudinal relaxation time distribution; the collected nuclear magnetic resonance data are preprocessed, and noise interference is removed; according to the shale reservoir fracture and cement analysis method provided by the invention, the shale reservoir core sample is obtained, and the nuclear magnetic resonance technology is utilized to perform data acquisition and analysis, so that the porosity of the core sample can be accurately calculated, the existence condition of the fracture and the cement can be accurately judged, and the fracture volume can be further calculated; the components and the content of the cement are analyzed, so that the analysis accuracy and the analysis reliability are greatly improved.

The invention relates to the field of data processing, in particular to a composite insulator vulcanization uniformity detection method and device. The method comprises the following steps: acquiring an NMR spectrogram of a vulcanized insulator; performing first-layer decomposition processing on the NMR spectrogram by using a wavelet filtering algorithm to obtain a detail coefficient; a noise detail coefficient and a signal detail coefficient in the approximation coefficient are distinguished; performing second-layer decomposition processing on the approximation coefficient to obtain a detail coefficient; calculating the signal purity; in response to the fact that the signal purity is smaller than a preset purity threshold value, noise detail coefficients in the detail coefficients obtained through second-layer decomposition processing are screened out; continuing decomposition and calculating the signal purity, and stopping decomposition when the signal purity is not less than a preset purity threshold value; after the noise detail coefficient is corrected and adjusted, a denoised NMR spectrogram is reconstructed; therefore, vulcanization uniformity detection is realized. Therefore, the accuracy of vulcanization uniformity detection is improved by improving the accuracy of denoising.

A method for material detection may include extracting, from a material database, a resonance frequency for the target material. The method may further include comparing an application type to entries in a scan database. The scan database may store pre-defined scanning patterns and corresponding application types. The method may include extracting, from the scan database, a scan sequence for the application type. Also, the method may include instructing a gimbal to follow positions in the scan sequence. The method may also include transmitting into an environment an RF signal when the gimbal is at the positions in the scan sequence. The method may further include receiving a response signal from the environment. The method may include generating a haptic feedback to indicate a directionality or a proximity to the target material. The method may include analyzing the response signal for resonance characteristics that indicate a presence of the target material.

The invention relates to a novel thaumatin mutant as well as a preparation method and application thereof. The invention provides a thaumatin mutant. The thaumatin mutant comprises an amino acid sequence of SEQ ID NO: 5 and a 6His tag sequence. The invention also provides a construction method of pichia pastoris engineering bacteria for expressing the thaumatin mutant and a preparation method of the thaumatin mutant. The inventor constructs a novel thaumatin mutant through genetic engineering, and large-scale expression of the thaumatin mutant is realized by using a pichia pastoris expression system. Sensory evaluation proves that the novel thaumatin mutant has high sweetness, and his-tag has little influence on the sweetness of protein. Stable isotope labeling of the novel thaumatin mutant is realized through a stable isotope labeling technology and adjustment of culture medium conditions. A 1H-15N HSQC spectrogram is utilized to prove that the his-tag basically has no influence on the protein conformation.

A method of using the relaxation rate (R1 and / or R2) of solvent NMR signal to invasively or noninvasively assess whether vaccines and other aqueous-based pharmaceutical products have been frozen during transport and / or storage.

Provided is a method for determining huff and puff fluid volumes in multi-scale spaces of shale oil reservoirs, including the following steps: rock sample pretreatment; porosity stress sensitivity testing; high pressure hg injection testing and nuclear magnetic resonance testing benchmarking; online nuclear magnetic resonance testing; data processing and analysis. Firstly, a changing law of multi-scale spaces of shale oil reservoirs with an effective stress is characterized through a pore stress sensitivity measurement and online nuclear magnetic resonance measurement combined experiment, and then the huff and puff fluid volumes of multi-scale spaces of shale oil reservoirs under a condition of a certain stimulated reservoir volume are calculated. A usage amount of a fracturing fluid for a fracturing horizontal well in the shale oil reservoir is determined from the perspective of giving full play to the imbibition replacement role of micro-nano pores.

The invention belongs to the technical field of oil and gas field development, and particularly relates to a method for simultaneously evaluating shale oil reservoir CO2 diffusion characteristics and storage states and an experimental device thereof. The method comprises the steps that firstly, a sampled shale core is subjected to artificial fracture forming, and the basic physical property of the shale core is measured; sequentially saturating formation water and oil; obtaining T1 and T2 maps of the shale core by utilizing nuclear magnetic resonance; and finally, according to corresponding formulas, calculating the effective diffusion coefficient De of the CO2, the storage rate of the CO2, the proportion of the structural storage form and the dissolution storage form of the CO2, and the proportion of the adsorption storage form and the free storage form in the structural storage form. According to the method, experimental mechanism evaluation can be carried out on the shale oil reservoir CO2 diffusion mechanism and the storage state under pressure driving, the diffusion characteristics and the storage state of CO2 in the shale development process are determined, and reliable technical support and theoretical basis are provided for efficient development of shale oil and geological storage of CO2.

The invention discloses a shale hydrocarbon expulsion efficiency evaluation method, device, equipment and medium, and relates to the technical field of shale gas exploration and developing.The shale hydrocarbon expulsion efficiency evaluation method includes the steps that hydrocarbon generation quantity charts of shale under different total organic carbon TOC grades are constructed; testing the water saturation of the core sample of the shale to obtain the water saturation rate of the core sample; carrying out oil washing treatment on the rock core sample, and carrying out porosity test to obtain rock porosity and rock apparent density; obtaining a crude oil sample of a production layer where the core sample is located, and performing a crude oil physical property experiment to obtain crude oil density; when key parameters such as water saturation rate, rock porosity, rock apparent density, crude oil density and shale hydrocarbon generation quantity charts under different total organic carbon TOC grades of a core sample and key parameters of hydrocarbon release and migration in a hydrocarbon expulsion process are measured, a dynamic measurement process is adopted, and the dynamic measurement process can realize dynamic simulation of a hydrocarbon migration path; and finally, accurate evaluation of the shale hydrocarbon expulsion efficiency is realized.

The invention relates to a method for constructing a pork water-retaining property prediction model based on a low-field nuclear magnetic resonance technology. The method comprises the following steps: (1) preparing a sample; (2) sample low-field nuclear magnetic resonance signal acquisition and inversion; (3) measuring water-retaining property parameters of the sample; and (4) model construction and evaluation. According to the method, an LF-NMR instrument is used for analyzing and optimizing acquisition parameters of a pork sample, proper characteristic parameters are selected as input parameters, proper pork water-retaining property parameters are selected as output parameters, and a pork water-retaining property prediction model based on a neural network, support vector regression and a random forest is constructed. The prediction method provided by the invention provides a scientific basis for the water-retaining property change of the pork in the processing, storage and transportation processes, and also provides more efficient and accurate detection service for food quality and safety monitoring.

The invention belongs to the technical field of shale oil development and research, and discloses a shale oil mobility evaluation method based on a two-dimensional nuclear magnetic resonance experiment, which comprises the following steps: dividing an oil-containing shale sample harvested by a closed coring well into three parts which are respectively marked as a sample 1, a sample 2 and a sample 3; carrying out a TOC determination experiment on the sample 1 to obtain the TOC content of the sample; carrying out a step-by-step pyrolysis experiment on the sample 2 to obtain the contents of the sample S1-1 and the sample S2-2; calculating to obtain a shale oil mobility evaluation factor which is marked as FMO; carrying out a two-dimensional nuclear magnetic resonance experiment on the sample 3 before and after centrifugation to obtain the movable oil content of the sample before and after centrifugation, calculating to obtain the percentage of two-nuclear magnetic resonance movable oil, and recording the percentage as MO2D-NMR; and shale oil mobility evaluation is realized through analysis of the relationship between MO2D-NMR and FMO. According to the method provided by the invention, nondestructive testing of the sample can be realized in the two-dimensional nuclear magnetic resonance experiment process, the loss of light hydrocarbon can be reduced to the greatest extent, and the mobility evaluation precision of shale oil is effectively improved.