23 results about "Proton NMR" patented technology

The invention discloses a nuclear magnetic resonance hydrogen spectrum method for directly analyzing a high molecular weight hyaluronic acid structure and quantitative monomer composition. The method comprises the following steps: S1, dissolving a high-molecular-weight hyaluronic acid sample in D2O, adding NaOD, and uniformly mixing to obtain a sample solution; the concentration of the hyaluronic acid sample in the D2O is 0.5 to 2 mg / mL; the final concentration of the NaOD in the sample solution is 75 mmol / L; s2, performing a nuclear magnetic resonance hydrogen spectrum test on the sample solution to obtain a nuclear magnetic resonance hydrogen spectrum spectrogram; and S3, obtaining an integral area proportion of a hydrogen atom characteristic peak from the nuclear magnetic resonance hydrogen spectrum so as to directly quantify the composition molar ratio of the two monomers of the high-molecular-weight hyaluronic acid. The method provided by the invention not only can realize direct structural characterization of the high molecular weight HA, but also can realize direct quantification of the composition proportion of the two monosaccharides, and the quantitative result is high in precision and reproducibility.

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 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.

The present disclosure relates to a process for preparing particles of a sulfide solid material (M) comprising at least Li, P, S and X elements, comprising the step of providing a powder of lithium sulfide (Li2S) comprising less than 0.2 wt % of residual LiOH as measured by solid state proton NMR and having a solid state proton NMR spectrum showing a peak signal at -2.0 ± 0.2 ppm that corresponds to less than 0.005 wt % of equivalent LiOH. It also relates to particles obtained by said process and their use for the preparation of an electrode, of an electrolyte layer of an electrode or of a separator.

The application relates to the structural composition of a [2+2] photocycloaddition polymer and a preparation method thereof, and relates to the technical field of functional materials. The polymer introduces a closed dodecaborane anion, two polymers are prepared by the application, and the two polymers can both undergo [2+2] cycloaddition under the irradiation of ultraviolet light. The [2+2] cycloaddition of the polymer is verified by nuclear magnetic resonance hydrogen spectrum, single crystal X-ray diffraction spectrum, powder single crystal X-diffraction spectrum, infrared spectrum and the like. The application shows the great potential of a supramolecular organic framework material based on B 12 H 12 2‑ in the field of topological chemistry, and lays a solid foundation for the in-depth research in the field in the future.

The invention discloses a permeability coefficient dynamic calculation method, system and equipment based on multi-source sensing and a medium, and belongs to the technical field of seepage monitoring, the permeability coefficient dynamic calculation method based on multi-source sensing comprises the following steps: step 1, according to a layered layout and risk area encryption principle, constructing a construction monitoring area; a distributed optical fiber, a proton nuclear magnetic resonance (NMR) sensor, a micro-seismic sensor, a pore water pressure auxiliary sensor and a solute concentration auxiliary sensor are arranged, and strain, pore water distribution, a micro-seismic event, pore water pressure and solute concentration data are synchronously acquired through an edge computing node and 5G transmission. And a microseismic sensor is matched to capture microcrack initiation and expansion in real time, and macroscopic and microscopic association mapping is constructed.

This invention discloses a compound with a (9β-H)-pinene core that inhibits weed growth, its preparation method, and its applications. In this invention, the ethanol extract of the tuberous part of *Cornus mansoni* is purified by macroporous resin column chromatography, followed by recrystallization and C244-distillation. 18 Gradient elution was performed using reversed-phase medium-pressure column chromatography; finally, its chemical structure was identified by methods such as proton NMR, carbon NMR, and comparison with literature data. The compound icacenone in this invention exhibits significant inhibitory effects on the root growth of Arabidopsis thaliana, barnyard grass, and foxtail grass, while remaining safe for the growth of rice and Job's tears, making it a potential pesticide formulation for developing biological herbicides.

The invention provides polylactic resin as well as a preparation method and application thereof. The nuclear magnetic resonance hydrogen spectrum of the polylactic acid resin has a first characteristic peak and a second characteristic peak, the first characteristic peak is located at 4.2 ppm to 4.4 ppm, the second characteristic peak is located at 4.0-4.2 ppm, and the ratio of the integral value of the first characteristic peak to the integral value of the second characteristic peak is (0.5-0.8): 1. The resin is high in light transmittance, low in haze and excellent in mechanical property and degradation property.

The invention relates to the technical field of drug detection and chemical analysis, in particular to a qualitative and quantitative detection method for alkyl nitrite substances by an NMR (nuclear magnetic resonance) method, and aims to solve the problems that when the alkyl nitrite substances are detected in the prior art, the alkyl nitrite substances are complex in matrix and cannot be accurately qualitatively detected, and the detection accuracy is poor. In order to solve the problems that in the prior art, a sample to be detected is directly detected after being dissolved in a deuterated reagent at room temperature by utilizing the low-temperature detection characteristic of NMR (nuclear magnetic resonance), and by combining a hydrogen nuclear magnetic resonance spectrum, a one-dimensional selective excitation total correlation spectrum and a diffusion sequencing spectrum, the content of the alkyl nitrite substances is determined. Reliable qualification in a complex matrix is realized; meanwhile, absolute quantification is realized by adopting a stable and easily available internal standard substance 1, 4-dimethoxybenzene, and a deconvolution fitting algorithm is introduced to process signal overlapping in combination with a quantitative nuclear magnetic resonance hydrogen spectrum and a quantitative nuclear magnetic resonance carbon spectrum, so that the anti-interference capability and the result credibility of quantitative detection are improved.

The invention discloses a solubility determination method based on a nuclear magnetic resonance hydrogen spectrum technology. The method comprises the following steps: 1, preparing a saturated solution from a sample by using a solvent, and placing the saturated solution in a nuclear magnetic sample tube; 2, placing the nuclear magnetic sample tube in a superconducting nuclear magnetic resonance spectrometer, and measuring a 1HNMR spectrogram of the saturated solution to obtain a spectral peak signal; the nuclear magnetic test parameters and conditions are as follows: the pulse sequence is zg or zg30, the measurement temperature corresponds to the solubility test temperature, and the time is stabilized for more than 10 minutes after the temperature balance is reached; 3, analyzing the spectrum peak, selecting a sample characteristic peak and a solvent characteristic peak, and carrying out integration to obtain the solubility of the sample; the method is based on a nuclear magnetic resonance technology (1H NMR), and the solubility is calculated according to a saturated solution sample characteristic signal and a solvent characteristic signal. The method has the characteristics of simplicity, feasibility, high efficiency, high precision, strong specificity, small dosage, economy, environmental protection and the like, and has a wide application prospect in the aspects of solubility determination and application of most organic matters and the like.

The invention provides a synthesis method of a fumaric acid modified nonionic surfactant, which comprises the following steps: placing BASF fatty alcohol-polyoxyethylene ether in a dry reaction bottle, and then adding fumaric anhydride; oxygen removal and low-temperature dissolution: introducing nitrogen into the reaction bottle for thorough purging so as to completely remove air in a reaction system, sealing the reaction bottle after purging is completed, and heating the sealed reaction bottle in an oil bath pan so as to completely dissolve fumaric anhydride to obtain a mixed solution; catalytic grafting reaction: adding a catalyst into the mixed solution, then gradually heating and continuously stirring, in the reaction process, monitoring the reaction progress in real time through a nuclear magnetic resonance hydrogen spectrum, and judging that the reaction is completed when monitoring that a fumaric acid double-bond characteristic peak disappears and a maleic acid double-bond characteristic peak appears, so as to obtain a reaction mixture; product post-treatment: cooling the reaction mixture to room temperature, standing, removing white precipitate, and collecting residual liquid, namely a crude product of grafted fumaric acid; and determining the grafting rate.

The invention discloses a preparation method of calipteroxin and an application of the calipteroxin in preparation of a marker for detecting peucedanum praeruptorum dunn. The preparation method comprises the following steps: extracting, separating and purifying a peucedanum praeruptorum dunn medicinal material to prepare the calipterixin, detecting a hydrogen-carbon spectrum of the peucedanum praeruptorum dunn by using a nuclear magnetic resonance spectrum, determining that the structure is calipterixin by comparing nuclear magnetic resonance hydrogen-carbon spectrum data in literature, and mixing and extracting peucedanum praeruptorum dunn and peucedanum praeruptorum dunn powder in a gradient proportion to obtain the peucedanum praeruptorum dunn. The UPLC method is used for qualitatively and quantitatively detecting the content of the peucedanum praeruptorum dunn mixed extracting solution calpteroxin in the peucedanum praeruptorum dunn, so that the aim of controlling the quality and the safety of the peucedanum praeruptorum dunn is fulfilled. The UPLC method is used for qualitatively and quantitatively determining the limit standard of the doped peucedanum praeruptorum dunn marker calipteroxin in the peucedanum praeruptorum dunn, and the method has the characteristic of accurately, stably and quickly detecting the doped peucedanum praeruptorum dunn in the peucedanum praeruptorum dunn, so that a scientific basis is provided for ensuring the safety and effectiveness of peucedanum praeruptorum dunn clinical medication.

This invention belongs to the field of biomedical technology, specifically relating to an isoflavone compound, its preparation method, and its application. This compound is derived from *Rotenoporosis capillaris* (a type of vine). Derris eriocarpa The stem of *Derris fusiforme* was analyzed using 1D and 2D nuclear magnetic resonance (NMR) spectra (1H NMR, 1C NMR, and high-resolution mass spectrometry), and its structural formula is shown below: Chemical name: 5-hydroxy-6-(2"-hydroxy-3"-methylbut-3"-enyl)-3-(4'-hydroxyphenyl)-7-methoxyisoflavone. Screening using the Sci-finder database revealed that this compound is a novel isoflavone, isolated for the first time from *Derris fusiforme*. Lipid-lowering activity experiments showed that at the same drug concentration (25 μg / mL) as the positive control, it significantly reduced intracellular total cholesterol and triglyceride levels. p <0.001). Therefore, this novel isoflavone compound can be used to prepare drugs, health products, functional foods, or special medical foods for the prevention or treatment of hypertriglyceridemia, hyperlipidemia, obesity, or metabolic syndrome.

The invention discloses a production process of deuterated sodium hydroxide d1, and belongs to the technical field of fine chemical engineering. The production process of the deuterated sodium hydroxide d1 provided by the invention mainly comprises the following steps: dropwise adding water into sodium peroxide solid powder under the conditions of argon atmosphere and ice salt bath, and monitoring the reaction through a nuclear magnetic resonance hydrogen spectrum, so that the reaction progress is effectively monitored, and the reaction is ensured to be complete. Through the anti-conventional addition method, the phenomenon that sodium peroxide is damped and gelatinized in a traditional production method can be effectively avoided, reaction conditions are easy to control, and a stable deuterated sodium hydroxide d1 product with a high deuteration degree can be obtained. And in the production process, a manner of dropwise adding water in stages is adopted, so that on one hand, adverse effects caused by intense reaction degree in the early stage of the reaction can be prevented, and on the other hand, complete reaction can be promoted, and the production efficiency of the deuterated sodium hydroxide d1 can be improved.

The application discloses a detection method of phenolic antioxidant additives in insulating oil, and belongs to the technical field of insulating oil detection. The application adopts a nuclear magnetic resonance hydrogen spectrum internal standard method for quantitative detection, directly determines the mixed oil sample, an internal standard substance and a deuterated reagent, and calculates the additive content according to the integral area ratio of characteristic quantitative peaks. The chemical shifts of the characteristic quantitative peaks of the internal standard substance and the characteristic quantitative peaks of the phenolic antioxidant additives in the insulating oil are located in the medium field intensity area of the spectrum, and the chemical shifts are not overlapped. The application overcomes technical difficulties such as complicated pretreatment, interference of complex oil matrix, use of toxic reagents and strong dependence on standard products of traditional methods. The detection method has the advantages of small sample consumption, fast analysis speed, green environmental protection, simple operation and the like, and the detection limit can reach 0.004%, and can realize rapid, accurate and reliable quantitative analysis of the phenolic antioxidant additives in the insulating oil.

The invention discloses a computer implementation method for early screening of fetal congenital heart disease, computer equipment, a readable storage medium and a program product, and the method comprises the following steps: obtaining a nuclear magnetic resonance hydrogen spectrum based on a pregnant woman serum sample, the nuclear magnetic resonance hydrogen spectrum having a plurality of nuclear magnetic peaks including a choline peak; by taking the characteristic value of the choline peak as a reference, carrying out normalization processing on the characteristic values of all the nuclear magnetic peaks to obtain normalized nuclear magnetic peak values, combining the normalized nuclear magnetic peak values to form a variable map, and taking the variable map as at least one part of the to-be-detected sample; and inputting a to-be-tested sample into the trained classifier, and outputting a fetal congenital heart disease risk prediction result by the classifier. Detection is performed based on a pregnant woman serum sample, so that the medical cost is lower, and clinical popularization is easy; screening can be carried out in 16-18 weeks of pregnancy, and the screening window period is earlier; through test classification, the average accuracy rate is 75% or above, and the early detection rate of the fetal congenital heart disease is guaranteed.

The invention discloses an intelligent compound identification method and system based on a nuclear magnetic resonance hydrogen spectrum, and the method comprises the steps: building training data based on the generation of a Voigt peak-type simulation spectrum and an experiment spectrum, considering a mixed hydrogen spectrum of noise and distortion, building a deep learning model integrating down-sampling, position coding and a coding and decoding attention mechanism, and carrying out the recognition of a target compound. And aligning pure spectrum and mixed spectrum features through cross attention, outputting a compound existence probability, and training by adopting binary cross entropy loss and an Adam optimizer to realize end-to-end automatic identification. According to the method, a data set composed of a high-fidelity theory simulation hydrogen spectrum and an experiment extension spectrum is constructed, and a deep learning model fusing position coding and a coding and decoding attention mechanism is designed, so that end-to-end, high-precision and automatic recognition of compounds in a complex mixture is realized.

Embodiments of the present disclosure are directed to functionalized copolymers produced by copolymerization of at least one conjugated diolefin monomer and at least one vinyl monomer, the functionalized copolymer including at least one functional group having silica reactive moieties, wherein the functionalized copolymer has a degree of hydrogenation of 75% to 98 mol % as measured using proton nuclear magnetic resonance spectroscopy (1H NMR). In one or more embodiments, the silane modifier may include an oxygen-containing moiety, wherein the oxygen atom of the oxygen-containing moiety may not be directly bonded with the silicon atom.

The application discloses a quality control method of aconite medicinal herbs based on quantitative nuclear magnetic resonance hydrogen spectrum technology, which comprises the following steps: extracting aconite medicinal herbs by using ethyl acetate, dissolving the extracted liquid in deuterated acetone after drying, adjusting the pH to 1.0-2.0, measuring nuclear magnetic resonance hydrogen spectrum data, and calculating the content of monoester type alkaloids and diester type alkaloids through quantitative peaks. The method is simple, fast and does not need corresponding reference substances, and the quantitative limit can reach 0.2 mM. Moreover, more monoester type alkaloids and diester type alkaloids can be detected, the application range is wide, and the quality of aconite medicinal herbs can be more comprehensively evaluated and controlled.

The application discloses a kind of prussian blue positive electrode material water characteristics test method, it is related to instrument analysis technical field.Utilize the different chemical environment hydrogen of nuclear magnetic resonance hydrogen spectrum H-NMR to hydrogen signal and after experiencing pulse excitation, free decay characteristic time is different, by thermogravimetric calibration and H-NMR free decay curve fitting, obtain prussian blue total water content and water distribution.When detecting the water characteristics unknown prussian blue sample, only need nuclear magnetic resonance hydrogen spectrum H-NMR detection obtains free decay curve, according to the calibration line that has been determined, total water content can be obtained;According to the characteristic decay time of different types of water that has been detected, free decay curve fitting, water distribution of the prussian blue sample to be measured can be obtained.Compared with thermogravimetric method, the test method obtains prussian blue water characteristics result test time short (only minute level), non-destructive to sample, test condition and operation method are simple, high accuracy and good stability, suitable for the rapid test of prussian blue water characteristics.

This invention discloses the cloning and application of a mannuronic acid C5-isomerase gene related to high-temperature response in kelp, belonging to the field of biotechnology. This invention screens out a mannuronic acid C5-isomerase (MC5E) gene related to high-temperature stress response in kelp; based on this, specific primers are designed to clone the gene from kelp. MC5E The cDNA sequence of the gene was obtained; soluble recombinant protein was successfully expressed using a prokaryotic expression system, and high-purity MC5E protein was purified; 1H NMR spectroscopy analysis showed that this recombinant protein can convert mannuronic acid (M) in alginate to guluronic acid (G), increasing the G content in alginate; quantitative real-time PCR detection showed that under high temperature stress, kelp larvae... MC5E The significantly elevated transcription level of the gene indicates its involvement in kelp's response to high-temperature stress.

The invention discloses a method for testing water characteristics of a Prussian blue positive electrode material, and relates to the technical field of instrument analysis. The total water content and the water distribution of the Pram are obtained through thermogravimetric calibration and H-NMR free attenuation curve fitting according to different free attenuation characteristic time of a hydrogen signal and hydrogen in different chemical environments after pulse excitation by utilizing H-NMR (nuclear magnetic resonance). When a Principal blue sample with unknown water characteristics is detected, a free attenuation curve is obtained only through H-NMR detection, and the total water content can be obtained according to the measured marked line; and fitting the free attenuation curve according to the characteristic attenuation time of the detected different types of water to obtain the water distribution of the to-be-detected Pulan sample. Compared with a thermogravimetric method, the test method has the advantages of short test time (only minute level) for obtaining the characteristic result of the Principal blue water, no damage to samples, simple test conditions and operation method, high accuracy and good stability, and is suitable for rapid test of the characteristics of the Principal blue water.

The invention discloses a structural characterization method of a phosphatidylcholine compound, and belongs to the technical field of analytical chemistry. The method comprises the following steps: dissolving a phosphatidylcholine sample in a deuterated solvent to prepare a nuclear magnetic test sample; detecting the sample by using a nuclear magnetic resonance spectrometer to obtain combined nuclear magnetic resonance spectrogram data including a one-dimensional nuclear magnetic resonance hydrogen spectrum, a one-dimensional nuclear magnetic resonance carbon spectrum and three different two-dimensional nuclear magnetic resonance spectrums; and comprehensively analyzing the combined nuclear magnetic resonance spectrogram data to determine the molecular structure of the phosphatidylcholine compound, including affiliating the chemical shift of main chain skeleton atoms and side chain atoms, and confirming the connection relationship between the atoms. The method provided by the invention solves the problem that the traditional chromatography and mass spectrometry method cannot accurately identify the phosphatidylcholine atom connection mode and molecular skeleton, can comprehensively and accurately characterize the fine structure of phosphatidylcholine, and provides a reliable technical basis for structural identification, quality control and quantitative research of the compounds.