6 results about "T2 value" patented technology

The invention relates to the technical field of tobacco leaf detection, in particular to a tobacco leaf oil content quantitative characterization method. The method comprises the following steps: measuring state information of protons in a tobacco leaf sample by using low-field nuclear magnetic resonance to obtain a spin-spin relaxation time T2 spectrum and a spin-lattice relaxation time T1 spectrum, and generating a T1-T2 two-dimensional spectrogram; determining peak positions of low-activity protons and medium-activity protons in the T1-T2 two-dimensional spectrogram to obtain T2 values of the low-activity protons and the medium-activity protons, and solving an average T2 value of the low-activity protons and the medium-activity protons of the plurality of groups of tobacco leaf samples; on the spin-spin relaxation time T2 spectrum of the tobacco leaf sample to be detected, the low-activity proton peak intensity and the medium-activity proton peak intensity of the tobacco leaf sample to be detected at the average T2 value are obtained, and the ratio of the low-activity proton peak intensity to the medium-activity proton peak intensity serves as the oil content quantitative value of the tobacco leaf sample to be detected. According to the method, nondestructive testing of the tobacco leaf raw material oil content is realized by utilizing a low-field nuclear magnetic technology, and quantitative characterization of the tobacco leaf raw material oil content is realized by combining the T1-T2 two-dimensional spectrogram.

The invention discloses a method for researching an MOF (Metal Organic Framework) synthesis process by utilizing a low-field nuclear magnetic imaging device, and belongs to the technical field of material synthesis process analysis. The method comprises the following steps: firstly, preparing a metal source solution and an organic ligand solution; one of the solutions is selected for low-field nuclear magnetic resonance relaxation time measurement, and imaging sequence parameters are optimized; mixing the two solutions, and immediately putting the mixed solution into a low-field nuclear magnetic imaging device; and carrying out continuous relaxation time weighted imaging and layered relaxation time measurement on the reaction process by using the optimized imaging sequence. The lossless, in-situ, visual and quantitative monitoring of the metal-organic framework material in the nucleation, growth and sedimentation process is realized by analyzing the change of image signal intensity in time and space and the change trend of relaxation time (such as T2 value) of different liquid layers along with time. According to the method, required equipment is simple, operation is convenient and fast, and an innovative research means is provided for deeply understanding the MOF synthesis mechanism and optimizing the synthesis process.

This application relates to the field of reservoir exploration technology, specifically to a method, device, storage medium, and electronic equipment for quantitative characterization of pore size across all scales, including: performing nuclear magnetic resonance analysis on the shale to be tested, obtaining the nuclear magnetic resonance T2 spectrum of the shale to be tested, and establishing a cumulative T2 probability curve; according to the formula r c =CT2 yields the pore size r corresponding to the T2 value with the same cumulative content. c Where C is the conversion coefficient; a cumulative pore size probability curve is established based on the pore size value and the corresponding cumulative content. This application can solve the problem of unclear pore size distribution in continental shale at all scales due to strong heterogeneity, and achieve quantitative characterization of pore size at all scales while avoiding damage to the shale under test.

The invention discloses a multi-parameter magnetic resonance quantitative imaging method and system, and relates to the technical field of MRI (magnetic resonance imaging), and the method comprises the steps: employing a multi-overlap echo sequence XMOLED, carrying out the simulation of magnetic resonance simulation software, and generating a simulation XMOLED image, constructing a simulation data set composed of a large number of paired simulation XMOLED images, simulation T2, T2 * and an apparent diffusion coefficient (ADC) quantitative graph, and training a deep learning neural network used for reconstruction of the magnetic resonance parameter quantitative graph; sequence parameters are configured on a magnetic resonance imaging instrument, an XMOLED signal of an actual imaging object is collected, and an XMOLED image of the actual imaging object is obtained through signal processing; and inputting the XMOLED image of the actual imaging object into the trained magnetic resonance parameter quantitative graph reconstruction network for reconstruction to obtain T2, T2 * and ADC quantitative graphs of the actual imaging object. According to the method, T2, T2 * and ADC quantitative diagrams can be obtained at the same time only through single-sequence XMOLED collection, the problem that scanning time is prolonged due to multi-sequence combined imaging is solved, and rapid and accurate multi-parameter quantitative magnetic resonance imaging is achieved.

The application discloses an infant brain T2 weighted magnetic resonance imaging optimization method based on a fast spin echo sequence. First, T1, T2 and PD quantitative imaging of the infant brain from 0 to 24 months old is collected to obtain T1, T2 and PD values of the infant brain white matter and gray matter regions, and according to the relationship characteristics of the infant brain white matter T2 value and the gray matter T2 value, the infant is divided into different month groups. Then, based on the 3D T2 weighted imaging of the variable flip angle fast spin echo sequence, the signal intensity of the infant brain white matter and gray matter under different refocusing flip angle chains is calculated through an extended phase graph algorithm, and the best flip angle chain design scheme of each group is determined with the maximum white matter / gray matter contrast as the target. The application fills the blank of the infant brain T2 weighted imaging optimization, formulates the best flip angle chain optimization scheme of different month groups, and thus significantly improves the contrast of the infant brain T2 weighted imaging.

The embodiment of the invention provides a nuclear magnetic resonance logging T2 spectrum borehole expanding correction method and device, equipment and a medium. The method comprises the steps that a slurry filtrate T2 value is determined according to the morphological change relation of a borehole diameter curve and a nuclear magnetic resonance logging T2 spectrum; re-inverting the measured echo string based on the T2 value of the slurry filtrate, and calculating the porosity Pmf of the slurry filtrate; calculating a corrected echo string of the slurry filtrate according to the T2 value of the slurry filtrate and the porosity Pmf of the slurry filtrate; and performing inversion on the corrected echo string, and calculating the corrected T2 spectrum of the mud filtrate. In the embodiment of the invention, the T2 value and the porosity of the slurry filtrate are determined by utilizing the change relationship between the hole diameter curve and the nuclear magnetic resonance logging T2 spectrum, and the T2 spectrum is corrected to eliminate the influence of the slurry filtrate, so that a more accurate T2 spectrum is provided for logging interpretation personnel to be used for interpretation and evaluation of a logging reservoir, and the interpretation and evaluation precision of nuclear magnetic logging is improved.