99 results about "Chemical shift" patented technology

The disclosure discloses a chemical-shift-encoded imaging method and apparatus based on phase unwrapping, and a device. Comprises: performing phase conversion on the phasor candidate solution for the purpose of enabling a difference between a correct solution and an inverse decomposition solution of the phasor candidate solution to be within a set range, and on the basis of a phase unwrapping method, performing determination to obtain an intermediate phasor solution; determining a true phase of the intermediate phasor solution, and converting the true phase to a phasor candidate solution space to determine a target phasor solution; and on the basis of the target phasor solution, determining a first chemical component signal and a second chemical component signal, and on the basis of the first chemical component signal and / or the second chemical component signal, performing chemical-shift-encoded imaging.

To provide a lubricating composition that can improve wear resistance in sliding parts of drive units or the like.SOLUTION: The present invention is a lubricating composition comprising P, wherein an analysis spectrum of 31P-NMR obtained in 1H complete decoupling mode satisfies the following conditions. Specifically, peaks are present in the vicinity of 3.5 ppm where the chemical shift value is 3.1 to 3.7 ppm and in the vicinity of 0 ppm where the chemical shift value is 0 to 0.3 ppm. A first peak area ratio (A2 / A1), which is the ratio of the peak area (A2) in the vicinity of 0 ppm to the peak area (A1) in the vicinity of 3.5 ppm, is 0.18 to 0.8. A peak that may appear in the vicinity of 7 ppm where the chemical shift value is 6.5 to 7.5 ppm has a height of 0.1 times or less relative to the peak in the vicinity of 3.5 ppm.SELECTED DRAWING: Figure 5A

This invention relates to the field of molecular sieves, specifically to a P-modified metal-doped MWW molecular sieve, its preparation method, and its applications. In this molecular sieve, A... Pδ‑7 / A P ≥50%, A Pδ‑7 represent 31 The peak area of ​​the P species signal peak at the terminal group with a P chemical shift of -7ppm ± 15ppm in the P MAS NMR spectrum, A P It represents 31 The peak area of ​​the total signal peak in the pMAS NMR spectrum. The molecular sieve of this invention has high activity, selectivity, and stability, and excellent resistance to carbon deposition.

The xylylene diisocyanate composition contains a xylylene diisocyanate and a specific compound. When the xylylene diisocyanate composition is mixed with deuterated chloroform and the mixture is subjected to 1H-NMR measurement, the specific compound has a peak in a chemical shift value range of 2.44 ppm to 2.46 ppm based on chloroform in the deuterated chloroform.

The present invention discloses a method for cyclodextrin molecular recognition based on nuclear magnetic resonance. The method comprises: modifying cyclodextrin with imidazole groups, using nuclear magnetic resonance to identify guest molecules with carboxyl or sulfonic acid groups using the modified cyclodextrin, and obtaining nuclear magnetic resonance spectra before and after cyclodextrin inclusion. If the peak of the monomer in the mixture spectrum shows a chemical shift and peak shape change compared to the spectrum of the cyclodextrin, it indicates that there is an interaction between the host and the guest. The present invention provides a method for the specific recognition of cyclodextrin by guest molecules based on nuclear magnetic resonance detection. The method is simple to operate and has good recognition effect, which is of great significance for the development of new molecular recognition systems.

A toner comprising a toner particle comprising a magnetic body, and a silica fine particle on a surface of the toner particle, wherein fragment ions corresponding to a D unit structure are observed in a specific measurement; when the silica fine particle is dispersed in a mixed solution of ethanol and aqueous solution of NaCl, followed by a titration operation using sodium hydroxide, a titer is within a specific range; in a chemical shift obtained by a specific measurement, with D as an area of a peak having a peak top present in a range from −25 to −15 ppm, and with D1 as an area of a peak having a peak top present in a range of more than −19 ppm and −17 ppm or less, D and D1 are in a specific ratio; and the magnetic body is present on the surface of the toner particle.

This invention discloses a water-soluble melanin CEST contrast agent, its preparation method, and its application, relating to the field of magnetic resonance imaging contrast agent technology. This contrast agent, its preparation method, and its application aim to solve the technical problem that existing contrast agents containing paramagnetic metals can damage liver and kidney function. This water-soluble melanin CEST contrast agent comprises the following components by weight: 2-3 parts ammonia, 40 parts ethanol, 100 parts deionized water, and 0.5 parts reaction substrate. The chemical shift corresponding to this contrast agent preparation method is 4.0 ppm, exhibiting good adaptability to acidic environments and suitability for use in the tumor microenvironment. It is polymerized using dopamine hydrochloride or 3,4-dihydroxyphenylalanine, with inexpensive, simple, and readily available raw materials, simple synthesis, and easy large-scale preparation. It achieves tumor imaging without the need for paramagnetic metal ions, avoiding the damage to liver and kidney function caused by heavy metal ions.

The application discloses a rapid detection method of paraffin in beeswax. The detection method comprises the following steps: dissolving the to-be-detected beeswax sample by using a deuterium solvent to perform nuclear magnetic resonance hydrogen spectrum test, and qualitatively and quantitatively analyzing the paraffin in the beeswax according to the nuclear magnetic resonance hydrogen spectrum result. Two conditions need to be met simultaneously when using the nuclear magnetic hydrogen spectrum to judge whether the paraffin is doped in the beeswax: (1) an ester characteristic proton peak appears near the chemical shift of 4.07 ppm; and (2) the relative integral intensity of the alkyl proton peak in the chemical shift range of 0.9-1.58 ppm is obviously enhanced compared with a standard spectrum. The detection method is simple and rapid, has good linear relationship, high accuracy and good repeatability.

The application discloses a kind of nuclear magnetic resonance spectrum peak position detection method, device and readable medium, by obtaining two-dimensional spectrum based on spin echo phase change spectrum, SEcho-Net neural network is constructed and trained, SEcho-Net neural network includes coding layer and decoding layer, coding layer includes indirect dimension down-sampling module and direct dimension down-sampling module, indirect dimension down-sampling module is used to compress two-dimensional spectrum based on spin echo phase change spectrum, and first feature vector is obtained, first feature vector is input in direct dimension down-sampling module and extracts key information related to spectrum peak position, and obtains key feature, and decoding layer includes direct dimension up-sampling module and step-by-step dimension reduction module, direct dimension up-sampling module is used to recover spectrum information from key feature, and second feature vector is obtained, and second feature vector is input in step-by-step dimension reduction module and carries out feature extraction, and obtains spectrum peak pure chemical shift position information.The method has low experimental requirements, and can accurately locate spectrum peak position.

The invention provides a compound of carboplatin and 1, 1-cyclobutane dicarboxylic acid and a detection method of the compound. A nuclear magnetic resonance hydrogen spectrum and a nuclear magnetic resonance carbon spectrum of the carboplatin and 1, 1-cyclobutane dicarboxylic acid eutectic compound in a D-(+)-glucose heavy water solution with the mass fraction of 5%, a nuclear magnetic resonance hydrogen spectrum and a nuclear magnetic resonance carbon spectrum of carboplatin in a 1.2. 3. 4-cyclobutane tetracarboxylic acid heavy water solution with the mass fraction of 2%, and a 1, 1-cyclobutane dicarboxylic acid eutectic compound with the mass fraction of 1, 1-cyclobutane dicarboxylic acid are measured. A nuclear magnetic resonance hydrogen spectrum and a nuclear magnetic resonance carbon spectrum of carboplatin and 1, 1-cyclobutane dicarboxylic acid in a D-(+)-glucose heavy water solution with the mass fraction of 5% are analyzed, and the structure of the carboplatin and 1, 1-cyclobutane dicarboxylic acid eutectic compound in water is determined by analyzing the chemical shift change of characteristic carbon atoms in the nuclear magnetic resonance carbon spectrum.

Enhanced EPI techniques are described that acquire and record a second set of scan data with the same flyback trajectory as that used to acquire a first set of scan data, only with a shifted starting point. Doing so ensures that both Nyquist ghosting and flow ghosting can be improved without changing a necessary echo spacing. This also reducing imaging distortion and chemical shift, and without changing the bipolar readout gradient. A full set (according to Nyquist) of all k-space lines can be yielded for each polarity of the bipolar readout gradient.

Provided are a ZSM-5 molecular sieve, a preparation method, and a lightening method. The total specific surface area of the ZSM-5 molecular sieve is 300-500 m2 / g, the external specific surface area of which accounts for 33-45% of the total specific surface area, and the ratio of the peak area of the peak at the chemical shift of 53 ppm in the nuclear magnetic spectrum of 27Al in the ZSM-5 molecular sieve to that of tetracoordinated Al is greater than or equal to 50%. The preparation method for the ZSM-5 molecular sieve comprises: S1, mixing a first silicon source, a first template agent, a first alkali source and water to obtain a seed gel, wherein the first silicon source is a solid silicon source; S2, mixing a second silicon source, an aluminum source, a second template agent, a second alkali source, water and the seed gel to obtain a synthetic liquid; and S3, crystallizing the synthetic liquid to obtain a ZSM-5 molecular sieve. Further provided are a ZSM-5 molecular sieve-based catalyst, a method for lightening light hydrocarbon and naphtha by using the ZSM-5 molecular sieve-based catalyst, and the use thereof. The ZSM-5 molecular sieve has a specific external specific surface area proportion, and the prepared catalyst can improve the yield of the cracking raw material under the conditions of a low hydrogen-oil volume ratio.

Method for obtaining a high-quality, purely chemical NMR shift spectrum, characterized in that it comprises the following steps: 1) Using the Matlab program to simulate a free induction attenuation signal and thus generate a purely chemical shift spectrum dataset for random NMR waves, and performing a Fourier transform of the FID signal to obtain a purely chemical NMR shift spectrum dataset and a corresponding labeling dataset; 2) Simulating the real-time ZS spectra as input data for a neural network by generating different chemical shift values, different signal-to-noise ratios, different spectrum peak intensities, different lateral relaxations, and different coupling strengths, and simultaneously simulating an ideal pure shift spectrum whose chemical shift, spectrum peak intensity, and lateral relaxation correspond to the simulated real-time ZS spectra, without coupling intensity information, without noise, and without data splice pseudopeaks as label data; creating a dataset with the input data and the label dataset, and dividing the dataset into a training set and a test set, which contains test data; 3) Perform preprocessing of data normalization for all datasets, including training set and test set; 4) Designing a structure of a neural network model of high-quality, purely chemical shift spectra that can achieve effects such as noise reduction, pseudopeak removal, linewidth reduction, and other effects; 5) Using the test data to test the neural network model, inputting the test data after preprocessing into the neural network model to obtain high-quality pure chemical shift spectra in order to output a high-quality pure chemical NMR shift spectrum that corresponds to the real-time ZS spectrum.

A data processing apparatus includes processing circuitry configured to: acquire data that are based on a magnetic resonance signal acquired from a specific region of an object, the data being acquired for detecting a chemical shift of substance; and perform relation calculation between a designated chemical shift arbitrarily designated in a predetermined range of the chemical shift and displacement amount of a position of the specific region displaced due to the designated chemical shift, as position correction data.

The application discloses a kind of based on nuclear magnetic spectrum automatic determination compound structure method, system, storage medium and terminal, belong to biochemical field, comprising: construct nuclear magnetic resonance chemical shift database;13C nuclear magnetic data in database is converted into long 400 feature vectors;The compound to be predicted is converted into long 400 feature vectors, the cosine similarity of the feature vector of the compound to be predicted and all feature vectors in database is calculated;The structure of the compound to be predicted is predicted according to the calculation result of cosine similarity.The present application is based on a large number of nuclear magnetic spectrum data, realizes that only according to nuclear magnetic spectrum data to molecular structure fast automatic prediction.

Provided herein is a noninvasive method for measuring pH, glucose and glycogen levels using a single acquisition method, as well as systems for performing the method. This method for glycogen / glucose (and pH) detection has high specificity enabled by superior chemical shift separation in high-strength magnetic fields. The methods have applications in detecting changing tumor microenvironments in cancerous cells for measuring important metrics for noninvasive and quantitative metabolic profiling.

A toner comprising a toner particle and an external additive, wherein the external additive comprises a silica particle and a hydrotalcite particle containing fluorine which is present in cross sections of the hydrotalcite particle, wherein, when a content of the hydrotalcite particle containing the fluorine and a content of the silica particle to 100 parts by mass of the toner particle are defined as Wh and Ws respectively, Wh and Ws are in specific ranges, and a sum of areas of peaks which are present in a range of −140 to 100 ppm of a chemical shift of the silica particle obtained by a solid-state 29Si-NMR DD / MAS method is defined as S, the area of the peak of a D unit and Q unit are defined as D and Q respectively, the Wh, the Ws, S, the D, and the Q satisfy a specific relationship.

The invention provides a real-time dynamic MRI (Magnetic Resonance Imaging) tumor imaging method and system based on compressed sensing, and relates to the technical field of medical imagines.The method comprises the following steps: acquiring two types of weighted image dynamic signal data generated by a detection device at different time points due to structural transformation through a compressed sensing technology; a multi-echo water-fat separation sequence is adopted for dynamic scanning, signals are separated according to water-fat chemical shift differences, and an initial water diagram and a non-water phase diagram are reconstructed and generated; performing time resolution analysis in combination with the dynamic signal data and the two types of images, generating a signal intensity curve of the detection device, and separating a specificity enhancement signal; and finally, in combination with the time dimension information, reconstructing the image by using a compressed sensing algorithm to obtain a dynamic enhanced image representing the target tissue, and according to the application, the artifacts are inhibited through the time evolution mode of the detection device, so that accurate real-time dynamic MRI tumor imaging can be realized.

The present application relates to the field of catalytic cracking, and discloses a propylene yield increasing additive, a preparation method thereof, a catalyst and application, and a hydrocarbon oil catalytic conversion method. The additive contains, based on the total dry basis amount of the additive, 24-35 wt% of P calculated as P2O5, 15-60 wt% of MFI structure molecular sieve based on the dry basis, and 1-8 wt% of M calculated as an oxide; wherein P includes P1 and P2; M includes M1, and M1 is selected from at least one of Group VIII metals; P1 and M1 interact with the MFI structure molecular sieve to form an active component; P2 exists in the form of a phosphorus aluminum inorganic binder; and the ratio of the peak area of the resonance signal with a chemical shift of 40±2ppm to the peak area of the resonance signal with a chemical shift of 55±2ppm in the additive measured by Al nuclear magnetic resonance spectroscopy is 1-20. 27 The additive is applied to a catalytic cracking reaction, and can effectively increase the ethylene and propylene concentrations in catalytic cracking liquefied gas and improve the heavy oil conversion capacity.

The invention discloses a three-dimensional nuclear magnetic resonance method and device for deeply annotating a biological extract. The method comprises the following steps: acquiring a 3D TOCSY J-reduced atlas of a target metabolite from a nuclear magnetic resonance spectrometer by setting a pulse sequence; the 3D TOCSY J-reduced atlas is processed through NMRPipe software, and processed three-dimensional nuclear magnetic data are obtained; analyzing and calculating the processed three-dimensional nuclear magnetic data through an R program to obtain a J coupling constant and chemical shift; carrying out characterization through a J coupling constant, chemical shift and peak multiplicity to obtain a spin system of the target metabolite; searching and matching the information of the spinning system in a nuclear magnetic database, identifying a target metabolite, and determining the attribution of the spinning system; and mapping a single peak of a high-resolution direct dimension of the belonging 3D TOCSY J-reduced atlas to a single peak in a high-resolution 1D < 1 > H NMR, and completing annotation of isolated and staggered multiple proton peaks of the 1D < 1 > H NMR. According to the method, the identification efficiency and accuracy of the metabolites in the complex biological sample are remarkably improved.

To provide a method for analyzing the higher-order structure of a nucleic acid.SOLUTION: Detecting a peak of imino proton within a range of chemical shift values of 10.0 to 16. 0ppm in a proton nuclear magnetic resonance spectrum; Determining the types of base pairs, optionally performing principal component and clustering analyses of the circular dichroism spectra, and optionally performing circular dichroism temperature shift measurements at single wavelengths in the range of 220 to 320nm; A step of performing curve fitting using a thermodynamic equilibrium model and performing evaluation, a step of performing ultraviolet temperature change measurement at a single wave length within a range of 290 to 300nm in some cases, and a step of determining that two or more types of nucleic acid higher-order structures including a guanine quadruplex structure are formed in a case where fitting to a state model indicating equilibrium of two or more states is shown, A step of determining that a guanine quadruplex structure is not formed when no fit to any state model indicating an equilibrium of two or more states is shown.SELECTED DRAWING: None

The invention provides an XPS spectrogram analysis method and system, computer equipment and a medium, and belongs to the field of surface analysis, and the method comprises the steps: obtaining to-be-recognized XPS spectrogram data; feature extraction of different scales is carried out on the XPS spectrogram data to be recognized according to the spatial dimension from high to low, and local region features corresponding to the physical attributes of all spectral peaks in the XPS spectrogram data to be recognized are obtained; performing up-sampling on the local region features to obtain a reconstructed spectrogram; fusing the local region features and the reconstructed spectrogram to obtain a fused feature map; performing physical attribute fitting on the fused feature map, matching physical attributes with a chemical shift reference range, and determining a chemical state; and constructing a fitting peak according to the physical attribute of the spectrum peak, and generating a background curve according to the chemical state of the XPS spectrogram data to be identified. According to the method, reliable chemical state information can be extracted without manual operation and fitting of detection personnel, and the reliability of an energy spectrum analysis result is ensured while the energy spectrum analysis efficiency is improved.

A lithium-containing oxide having a cubic garnet structure and wherein, when a solid-state 19F-NMR spectrum is measured under conditions where a 19F nucleus resonance frequency is 564 MHz, at least one peak is observed within a chemical shift range of −100 to 50 ppm, based on a chemical shift of polytetrafluoroethylene being −122 ppm.

The invention discloses a compound structure analysis method and system based on nuclear magnetic resonance data, and the method comprises the steps: receiving original nuclear magnetic resonance data, collected by a nuclear magnetic instrument, of a to-be-analyzed compound, preprocessing the original nuclear magnetic resonance data so as to convert the nuclear magnetic resonance data in a time domain form into nuclear magnetic resonance data in a frequency domain form, suppress noise interference and output a peak position list; constructing a solvent peak template matched with an actual spectrogram peak shape in the nuclear magnetic resonance data, delimiting candidate areas in the peak position list according to a configured search interval, and matching a signal of each candidate area with a signal of the solvent peak template to obtain a solvent peak; removing the solvent peak, calculating the offset between the actual chemical shift and the theoretical value, applying the offset to global chemical shift correction to obtain a chemical shift list, and performing structural analysis on the to-be-analyzed compound based on the chemical shift list. According to the invention, the problem of poor accuracy during compound structure analysis in the prior art is solved.

The present application relates to a kind of small molecule probes and its preparation method and application, the chemical structure of the probe is as shown in the following formula: Wherein, R1 is 1-propyl sulfonic acid or 1-butyl sulfonic acid;R2 independently selected from trifluoromethyl or sulfur pentafluoride group, the substitution position of R2 is the ortho, para or meta of hydroxyl on benzene ring;Preparation method is by the condensation reaction of salicylaldehyde containing fluorine substituent group and indoline, directly introduce containing fluorine substituent group into the spiro-pyran molecule structure with pH response, prepared with 19 F MRI and fluorescence imaging pH-responsive bimodal imaging small molecule probe.Compared with the prior art, the small molecule probe of the present application exhibits significantly different 19 F NMR chemical shift and fluorescence intensity, high-resolution 19 F MRI imaging and fluorescence imaging, greatly improve the sensitivity and accuracy of imaging, has important application prospect in the field of biosensing, cell imaging, medical diagnosis etc.

The invention relates to the technical field of image processing, and provides an auxiliary film reading analysis system in an MRI (Magnetic Resonance Imaging) image examination process, which comprises the following steps: acquiring a plurality of kidney MRI images of a patient; performing edge detection and contour analysis on the kidney MRI image to obtain a plurality of connected domains; acquiring a banding factor of each connected domain; obtaining an offset artifact possibility of each connected domain, and screening to obtain a plurality of suspected chemical shift artifact regions; acquiring a plurality of kidney regions in the kidney MRI image; the kidney offset distance of each suspected chemical shift artifact area is obtained; obtaining the final artifact possibility of each suspected chemical shift artifact area, and screening to obtain a plurality of chemical shift artifact areas; and marking a chemical shift artifact area in each kidney MRI image, and assisting in reading and analyzing. The invention aims to solve the problem that chemical shift artifacts in MRI images affect film reading analysis.

The invention relates to the technical field of methane partial oxidation, in particular to a Fe-CHA catalyst, a preparation method thereof and a methane partial oxidation method. The atomic ratio of silicon to aluminum of the Fe-CHA catalyst is 8-10; in 29Si solid nuclear magnetism of the Fe-CHA catalyst, within the chemical shift range of-90 ppm to-120 ppm, four formants of delta 1 to delta 4 with gradually increased chemical shift exist, the normalized peak area of delta 1 is 6% + / -1%, the normalized peak area of delta 2 is 8% + / -1%, the normalized peak area of delta 3 is 11% + / -1%, and the normalized peak area of delta 4 is 75% + / -1%; the content of tetrahedral coordination mononuclear Fe is 29%-31%, the content of octahedral coordination mononuclear Fe is 47%-49%, and the content of oligomeric Fe is 21%-23%; the catalyst is used for partial oxidation of methane, and has the advantages of high methane conversion rate and high methanol and dimethyl ether selectivity at low temperature.

Silica particles includes a nitrogen-containing compound. The ratio of the integral C of a signal observed at a chemical shift of −50 ppm or more and −75 ppm or less in a 29Si solid-state nuclei magnetic resonance (NMR) spectrum of the silica particles, the 29Si solid-state NMR spectrum being obtained by cross polarization / magic angle spinning (CP / MAS), to the integral D of a signal observed at a chemical shift of −90 ppm or more and −120 ppm or less in the 29Si solid-state NMR spectrum, that is, C / D, is 0.10 or more and 0.75 or less. The amount X of the nitrogen-containing compound extracted from the silica particles with a mixed solution of ammonia and methanol is 0.1% by mass or more. The amount X of the nitrogen-containing compound extracted and the amount Y of the nitrogen-containing compound extracted from the silica particles with water satisfy Y / X<0.3.

The application relates to a magnetic resonance scan control method, a graphical user interface device system and a magnetic resonance imaging system. An initial positioning image of a magnetic resonance scan is acquired, and an excitation region of a metabolite of interest is selected in the initial positioning image of the magnetic resonance scan. An auxiliary mark is displayed on or around the excitation region of the metabolite of interest, and the auxiliary mark is associated with scan parameters. According to the auxiliary mark, an excitation region of an interfering metabolite is determined. It is judged whether the excitation region of the interfering metabolite exists. If the excitation region of the interfering metabolite does not exist, the magnetic resonance scan is performed by using the scan parameters; otherwise, the auxiliary mark is adjusted until the excitation region of the interfering metabolite does not exist. The magnetic resonance scan control method improves data quality and optimizes the problem that an interfering metabolite is excited due to a chemical shift effect.

The invention is suitable for the technical field of magnetic resonance imaging, and provides a radio frequency field non-uniformity correction method and device, electronic equipment and a program product. The method comprises the following steps: acquiring actual radio frequency field intensity of each position in a scanning object under two preset radio frequency field intensities and actual CEST signal intensity at a first chemical shift position and a second chemical shift position; determining a first ideal CEST signal intensity based on the actual radio frequency field intensity of the same position under the two preset radio frequency field intensities and the actual CEST signal intensity at the first chemical shift; determining a second ideal CEST signal intensity based on the actual radio frequency field intensity of the same position under the two preset radio frequency field intensities and the actual CEST signal intensity at the second chemical shift; and determining the GluCEST signal intensity based on the two ideal CEST signal intensities at the same position under the target radio frequency field intensity. According to the invention, the accuracy of GluCEST signal strength measurement can be improved.