73 results about "Chemical shift" patented technology

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.

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.

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.

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 application discloses a chemical shift encoding imaging method, device and equipment based on phase unwrapping, which comprises the following steps: acquiring an initial image, determining a field map candidate solution of the initial image; performing phase conversion on the candidate field map solution, taking the correct solution and the interval between the inverse solutions of the candidate field map solution as the target within a set range, determining an intermediate field map solution based on a phase unwrapping method; determining the real phase of the intermediate field map solution, and converting the real phase to the field map candidate solution space to determine a target field map solution; determining a first chemical composition signal and a second chemical composition signal based on the target field map solution, and performing chemical shift encoding imaging based on the first chemical composition signal and / or the second chemical composition signal. By converting the problem of selecting one of the phase vectors in different chemical compositions into a phase unwrapping problem, the stability and accuracy of chemical shift component separation are ensured under the condition that the acquisition parameters do not meet specific conditions, and the chemical shift encoding imaging effect is improved.

A negative electrode composite material includes a Si-M-C composite material. A conductive layer exists on a surface of the Si-M-C composite material, M includes at least one of boron, nitrogen, or oxygen. Chemical shifts of a silicon element in the Si-M-C composite material as measured in a solid-state nuclear magnetic resonance test include −5 ppm±5 ppm, −35 ppm±5 ppm, −75 ppm±5 ppm, −110 ppm±5 ppm. A peak width at half height at −5 ppm±5 ppm is K, and K satisfies: 7 ppm<K<28 ppm. The negative electrode composite material exhibits a relatively low expansion rate and a relatively high conductivity. A negative electrode plate and an electrochemical device made of the negative electrode composite material exhibit high cycle performance.

The application discloses a phosphorus-modified beta molecular sieve, characterized in that, after being treated under the condition of 800 DEG C, 17 hours and 100% water vapor atmosphere, the beta molecular sieve has the following characteristics: 29 The molar ratio of silica / alumina of the framework measured by Si MAS NMR is ≤40, 31 The ratio of the characteristic peak area of the chemical shift-17±3 resonance signal to the characteristic peak area of the chemical shift-30±5 resonance signal measured by P MAS NMR is ≥0.70.

The invention discloses a soil organic carbon source and stability rapid evaluation method based on a solid 13C nuclear magnetic resonance spectrum and an intelligent analysis system, and the method comprises the following steps: carrying out standard pretreatment on a soil sample, and detecting the soil sample by using a solid 13C nuclear magnetic resonance technology to obtain spectrum data; partitioning the obtained spectrum data according to a standard chemical shift interval, and calculating an integral area proportion of a partition corresponding to each chemical functional group; based on the molecular mixing model, constructing a linear equation set, and solving the mole fractions of the six chemical components in the soil sample by adopting a constrained least square programming algorithm; and calculating the proportions of plant source carbon, microbial source carbon and pyrolytic carbon in the soil sample according to the calculated mole fractions of the six chemical components. The carbon proportion of a plant source and a microorganism source can be effectively distinguished by combining solid 13C nuclear magnetic resonance and a molecular mixed model, and the carbon stability change in the grassland degeneration and recovery process is revealed.

The application relates to a fluorine nuclear magnetic resonance-based sulfur dioxide detection method, which first provides a high-sensitivity fluorine probe P1-CF3, which can rapidly react with sulfur dioxide, and the product formed is collected by nuclear magnetic resonance 19 F nuclear magnetic spectrum, can produce signal peaks at chemical shifts of -61.09ppm and -61.30ppm; further, the product yield can be measured according to the signal peak area, so as to judge the sulfur dioxide content in the sample. The fluorine probe P1-CF3 and the nuclear magnetic resonance detection method can realize qualitative and quantitative detection of the sulfur dioxide content in environmental samples or food samples, and the probe can also be used for detecting intracellular sulfur dioxide.

The invention discloses a production process of deuterated phosphoric acid-d3, and belongs to the technical field of fine chemical engineering. The production process mainly comprises the following steps: dropwise adding heavy water into phosphorus pentoxide by a reverse addition method for reaction under the conditions of argon atmosphere and ice salt bath, adjusting the temperature of the obtained product solution to 40-120 DEG C after the heavy water is dropwise added, continuing stirring reaction, monitoring in the reaction process in cooperation with a nuclear magnetic resonance phosphorus spectrum, and determining the content of phosphorus pentoxide in the phosphorus pentoxide. And when the observed phosphorus spectrum shows a single signal peak and the chemical shift is 0 ppm, the reaction is terminated. The application of the reverse addition method can effectively prevent phosphorus pentoxide from being affected with damp and gelatinized due to contact with water vapor, so that the regulation and control of the production process and the improvement of the quality of the deuterated phosphoric acid-d3 product are facilitated. The high-temperature treatment after the heavy water is dripped is matched with the nuclear magnetic resonance phosphorus spectrum detection, so that the reaction process can be visualized, possible byproducts in products can be effectively converted, and the purity and deuteration degree of the deuterated phosphoric acid-d3 can be improved.