91 results about "Stable nuclide" patented technology

The invention discloses a water pollution cross-domain traceability method based on multi-chain collaboration and stable isotope source analysis, and relates to the technical field of water environment monitoring, the method comprises the following steps: pollution source chemical fingerprint construction: collecting an environmental water sample and a potential pollution source sample in a drainage basin; adopting a mass spectrometer to detect stable isotope compositions such as delta 13C, delta 15N, delta 18O and the like in the pollutants; and performing morphological division on the pollutants by using a morphological grading extraction technology. Homology judgment precision is greatly improved through isotope and morphological analysis; cross-chain credible collaboration is achieved, multi-party data interaction is achieved, and timeliness and accuracy of pollution tracing are guaranteed; the space-time model traceability is combined with an evolution path and gridding mapping, so that the pollution inversion accuracy is improved; and ecological compensation support provides a quantitative basis for pollution intensity and diffusion range so as to support a compensation model.

The present invention provides a pretreatment method for determining the stable isotope ratio of non-exchangeable hydrogen in acetic acid, belonging to the field of stable isotope analysis of foods. The pretreatment method comprises the following steps: adding a reaction reagent to a vinegar sample extract to replace the carboxyl hydrogen in the acetic acid with the exchangeable hydrogen to achieve isotope exchange equilibrium. The present invention can be used to simply and rapidly determine the isotope ratio of non-exchangeable hydrogen in acetic acid in vinegar products and can be used in research and applications for detecting the authenticity or adulteration of vinegar products.

The invention relates to the technical field of biochemical detection and analysis, in particular to a method for screening halogenated carbazole active degrading bacteria based on a single-cell Raman spectrum technology, which utilizes the characteristic of more active substance exchange between high-activity microorganisms and the outside, adopts a stable isotope probe to anchor active strains, and performs targeted screening to obtain the halogenated carbazole active degrading bacteria. Therefore, the degrading bacteria are firstly screened and then cultured. Compared with other markers (13C and 15N), the deuterium (2D) marker is lower in price, and an obvious C-D tensile vibration band can be observed in a Raman silence region. According to the method, the time for screening the functional strain is shortened to several days from several months in the prior art, the performance of the active functional strain is improved by multiple times compared with that of the strain obtained through a traditional method, and the technical bottleneck that the single-active strain is difficult to effectively obtain through the traditional method is broken through.

The invention discloses a method for determining carbon isotopes of low-concentration soluble organic carbon in a water body, and belongs to the technical field of organic carbon detection. The determination method comprises the following steps: combining a TOC analyzer and a stable isotope mass spectrometer, and converting DOC in a water body into CO2 gas by adopting the TOC analyzer; cO2 gas generated by the TOC analyzer is enriched for the first time through the cold trap T1; the CO2 gas frozen by the cold trap T1 is enriched for the second time through a cold trap T2; introducing the CO2 subjected to secondary enrichment into a stable isotope mass spectrometer, and determining the carbon isotope composition of the CO2. Aiming at a low-concentration DOC water body, the carbon isotope composition of DOC in the water body is determined on the basis of combination of a wet oxidation technology and stable isotope mass spectrometry detection, a wet oxidation method is used for increasing the volume of a water sample to generate more CO2 for stable isotope mass spectrometry determination, so that more accurate carbon isotope composition is obtained, and the method is efficient, time-saving, labor-saving and accurate.

The invention belongs to the technical field of rainwater treatment, discloses a method for evaluating the water holding capacity of a bioretention facility, and aims to effectively evaluate the water holding capacity of the bioretention facility and provide scientific guidance for subsequent construction of the bioretention facility. According to the scheme, the method comprises the following steps: collecting a soil water sample and a rainfall inflow water sample of the bioretention facility; the outflow flow of the bioretention facility in the rainfall event is continuously monitored, and outflow water samples in different time periods are collected; respectively carrying out oxyhydrogen stable isotope detection analysis on the collected soil water sample, the rainfall inflow water sample and the outflow water samples in different time periods; respectively calculating the soil moisture in the effluent water sample at different time periods and the composition proportion of the rainfall inflow water component according to the detection analysis result, and dividing the soil moisture outflow process from the outflow flow; and evaluating the water holding capacity of the bioretention facility according to the soil moisture outflow process.

The invention discloses a mine water source identification method, system, equipment and medium based on a combined weight and grey relational degree theory, and relates to the technical field of mine water source identification, and the method comprises the steps: obtaining water quality parameters and stable isotope composition of a mine water sample, and building a comprehensive feature matrix; calculating the correlation degree between each water quality parameter and a preset water source type based on the comprehensive feature matrix, analyzing the composition and proportion of multi-source water mixing in the mine water sample, and determining a first mine water source identification result; and weighting the water quality parameters and the stable isotope composition in the comprehensive characteristic matrix by using a combined weight method, and obtaining a second mine water source identification result based on the weighted comprehensive characteristic matrix and the first mine water source identification result. The method has high prediction speed and prediction precision, the existence condition of the underground water source can be identified by using a geophysical prospecting method according to different geological conditions through the prediction model, and the acquisition process of the underground water burst source is more convenient.

The utility model relates to the technical field of gas transfer, and provides a sample introduction device for gas stable isotope value measurement, which comprises a containing tank with a containing space and a plurality of communicating pipes communicated with the containing space; the high-concentration gas injection pipe is arranged on the containing tank and communicated with the containing space, and high-concentration detection gas can enter the containing space through the high-concentration gas injection pipe. By means of the technical scheme, the technical problems that when a gas pre-concentration device is used in the prior art, gas cannot be directly supplied for high-concentration gas, the high-concentration gas can only be detected after being diluted in advance, the detection cost is increased, and the detection result has errors are solved.

The object of the present invention is to provide a stable isotope enrichment method that can reduce equipment costs and power without lengthening the start-up time and can achieve efficient enrichment. The present invention provides a stable isotope enrichment method, which is a method for separating stable isotopes using a plurality of distillation columns (the first column to the m-th column; m is an integer of 2 or more) connected in cascade. One of gas and liquid is supplied from a position near the bottom of the (n-1)-th column to a position near the top of the n-th column (1 < n ≤ m), and the other of gas and liquid is returned from a position near the top of the n-th column to a position near the bottom of the (n-1)-th column. In each distillation column, when the flow rate of the gas rising in the column is set as the first flow rate and the flow rate of the gas or liquid supplied from the previous column or the next column is set as the second flow rate, the second flow rate is set to 4% by volume or more of the first flow rate.

The invention relates to the technical field of metallurgy, and discloses an intelligent steelmaking process based on dynamic raw material proportioning, the core of the process is that a functional pellet with a core-shell-film multilayer structure is adopted, functional components sequentially acting in a molten pool are packaged in different layers of the functional pellet respectively, and the functional components are sequentially separated from the molten pool. The stable isotope tracers are in one-to-one correspondence with the functional components and can be released in sequence. A mass spectrometer sensing system is used for detecting specific time sequence signals formed by sequential release of the tracer agents on line, and the system can confirm the delivery and step-by-step reaction process of materials and conduct on-line self-correction on kinetic parameters in a metallurgical process model. According to the method, a closed-loop control system integrating precise feeding, process confirmation and model adaptive capacity is constructed, and adaptive control over the steelmaking process is achieved. The method can improve the control precision of molten steel components and temperature at the smelting end point, shorten the smelting period, and improve the overall production efficiency and the resource utilization rate.

The present application relates to a kind of detection methods of isotopic abundance in acetic acid, comprising the following steps: stable isotope labeled acetic acid is decomposed under vacuum and high temperature conditions, generates stable isotope labeled methane or carbon dioxide, can determine 13 C labeled in carboxyl site acetic acid CH3 13 COOH in 13 C isotopic abundance, 13 C labeled in methyl site acetic acid 13 CH3COOH in 13 C isotopic abundance, 18 O labeled acetic acid CH3C 18 O 18 OH in 18 O isotopic abundance, methyl deuterium isotopic abundance in deuterium labeled methyl site acetic acid CD3COOH;Compared with prior art, the present application has the advantages that the isotopic abundance in acetic acid labeled by stable isotope in different sites is detected, can be used for deuterium, 13 C or 18 O labeled acetic acid isotopic abundance determination, test data accuracy and precision etc.

The invention provides a medicine raw material homology judgment method and device, computer equipment and a medium, and belongs to the field of medicine identification, and the method comprises the following steps: obtaining a plurality of same sample medicines from different sources; determining the stable isotope abundance values of carbon, nitrogen, oxygen and hydrogen in the drug sample through a stable isotope ratio mass spectrometry and a chromium-assisted stable isotope ratio mass spectrometry; taking the stable isotope abundance value as a variable, and classifying sample drug sources by adopting a hierarchical clustering analysis and principal component analysis method to obtain a plurality of drug sources; obtaining stable isotope abundance values of to-be-classified target drugs, and respectively determining the stable isotope abundance values of the target drugs and Z values of the stable isotope abundance values of all classes based on a Z value analysis method; under the condition that the Z values of the stable isotope abundance values of all the elements are smaller than or equal to the preset threshold value, it is determined that the target drug and the sample drug of the corresponding category are homologous drugs, and therefore the accuracy of drug detection is improved.

The embodiment of the application provides a marine carbonate high-resolution sequence stratigraphic division method and device, and belongs to the technical field of geological exploration. The method comprises the following steps: obtaining logging data of a target well section, generating a first curve based on the logging data, the first curve being a curve for representing the rise and fall of the paleo-sea level of the target well section; obtaining stable isotope data of the target well section, correcting the first curve based on the stable isotope data, obtaining a second curve, and thus establishing a high-resolution sequence division scheme of a single well; obtaining a seismic profile of the target well section, determining a negative inflection point of the second curve, and calibrating the seismic profile based on different levels of the negative inflection point of the second curve, so as to determine a high-resolution sequence tracking scheme of the target well section; and the application can quickly and conveniently solve the problem of high-resolution sequence stratigraphic division and comparison.

The application relates to the technical field of plasma, in particular to a medical cyclotron beam centering adjustment method and system. The method comprises the following steps: acquiring a magnetic field sequence, a beam sequence and a current sequence; obtaining a beam fluctuation factor according to the difference in lag number corresponding to the maximum autocorrelation coefficient of the magnetic field sequence and the beam sequence, the correlation of the magnetic field sequence and the beam sequence, and the difference in the maximum autocorrelation coefficient; forming a beam fluctuation sequence by using the beam fluctuation factor; dividing the beam fluctuation sequence, and also dividing the current sequence; fitting a straight line based on the current fluctuation sequence and the current sequence; obtaining the current influence intensity at the current moment according to the difference between the excitation current in all sub-sequences and the overall excitation current of the current sequence and the mean square error; improving the proportional term according to the current influence intensity, controlling the excitation current based on the proportional term, and adjusting the proportional term in real time to optimize the magnetic field control effect. The application realizes higher and more stable nuclide production efficiency.

The invention discloses a method for high-precision detection of carbon stable isotope and content thereof in an environmental sample. The method provided by the invention comprises the following steps: detecting environmental sample powder by using an elemental analysis-stable isotope mass spectrometer; the sampling amount of the environmental sample powder is greater than or equal to 0.4 mg; in the detection process, inert gas is introduced into an opening flow divider in a Conflo universal interface of the elemental analysis-stable isotope mass spectrometer, and the inert gas is mixed with sample gas obtained by combustion in an elemental analyzer. According to the method provided by the invention, the situation that a sample signal is too high and exceeds a linear range is avoided, the representativeness of the sample is improved, the possibility of data abnormity caused by nonuniformity of the sample is reduced, and the aim of rapidly and accurately detecting the stable carbon isotope and the content of the stable carbon isotope at the same time is fulfilled.

The present invention belongs to the technical field of gas stable isotope determination, and provides 15 A pretreatment system and method for gas products of N tracer nitrification-denitrification. The pretreatment system of the present invention uses a chemical trap to remove CO2 and H2O from the gas products of nitrification-denitrification; the first cold trap can remove CO2, H2O, NH3, NO2 and N2O from the gas products of nitrification-denitrification; the oxygen is removed by using a high-temperature reduction furnace; then the trace carbon monoxide, small molecule organic matter and nitrogen are separated by using a separation column; and the residual CO2, H2O, NH3, NO2 and N2O are removed by using a second cold trap. The pretreatment system of the present invention can remove O2, NOx, CO2, H2O and small molecule organic matter from the gas products of nitrification-denitrification, which is beneficial to the accurate detection of N2 in the gas products of nitrification-denitrification.

The present invention proposes a method for determining the stable isotope ratio of non-exchangeable hydrogen sites of glycerol in edible oils and fats, belonging to the field of stable isotope analysis technology. The method comprises the following steps: a) preparing a preliminary glycerol sample; b) determining the stable hydrogen isotope ratio of glycerol in the preliminary glycerol sample using a gas chromatography-pyrolysis-stable isotope ratio mass spectrometer; c) selecting glycerol with a known stable isotope ratio of non-exchangeable hydrogen sites as a working standard substance, processing according to step a), and determining according to step b) to obtain the stable hydrogen isotope ratio of the glycerol working standard substance; and calculating the stable isotope ratio of the non-exchangeable hydrogen sites of glycerol in the edible oil to be tested by comparing the measurement result of the stable hydrogen isotope ratio of the glycerol working standard substance with the known stable isotope ratio of the non-exchangeable hydrogen sites of the glycerol working standard substance. The method is rapid and accurate, providing a new analytical method for adulteration detection and authenticity control of oils and fats.

The present invention relates to a 13 C. 18 The synthesis method of trifluoroacetic acid with O stable isotope double labeling is as follows: firstly, trifluoroacetic acid is dissolved in a solvent, metal ions are added, and 13 C-labeled carbon dioxide, react to obtain a reaction solution, then separate and dry the reaction solution to obtain 13 C-enriched trifluoroacetic acid, and finally 13 C-enriched trifluoroacetic acid is dissolved in an aprotic solvent, thionyl chloride is added, stirred for reaction, and then a catalyst and oxygen 18 water are added, heated for reaction, and the reaction product is separated to obtain 13 C. 18 O stable isotope double labeled trifluoroacetic acid is the target product. Compared with the prior art, the present invention has a simple reaction process, a simple post-processing process, and a high yield. 13 The C isotope abundance is over 98%. 18 The O isotope abundance is over 97%.

The utility model discloses a deashing device for an oxidation-reduction reaction tube, which comprises a bracket, a deashing device, a deashing device and a control device, wherein the bracket is provided with a fixing piece for vertically fixing the oxidation-reduction reaction tube to be dedusted; the driving rod can be inserted into the reaction tube to be dedusted, and can rotate and move up and down in the reaction tube; the upper end of the ash removal disc is fixedly connected with the lower end of the driving rod, and a plurality of ash removal teeth are arranged at the lower end; and the driving device is in transmission connection with the upper end of the driving rod and is used for driving the driving rod to rotate and move up and down. According to the deashing device for the oxidation-reduction reaction tube of the stable isotope mass spectrometer, ash attached to the inner wall of the reaction tube is ground off through the deashing teeth at the lower end of the deashing disc, efficient and automatic deashing of the reaction tube is achieved, and the labor intensity of an operator is greatly reduced.

The invention relates to the technical field of detection, and discloses a method for tracing the origin of silkworm cocoons based on a stable isotope technology in combination with a machine learning algorithm, and the method comprises the steps: (1) collecting data; (2) data preprocessing; (3) model optimization; (4) model training; and (5) producing area tracing. According to the invention, origin traceability of silkworm cocoons from different origins is realized based on isotope analysis and a machine learning algorithm. Specifically, hydrogen, oxygen, carbon and nitrogen stable isotope ratio data are combined with KNN, SVM and RF algorithms to realize rapid and high-precision source tracing of silkworm cocoon producing areas. According to the invention, by combining the advantages of various machine learning algorithms, the accuracy and reliability of silkworm cocoon origin tracing are improved.

The invention provides an experimental method for determining stable carbon and oxygen isotopes by a two-way sampling method, and relates to the technical field of stable isotope analysis. The experimental method comprises the following steps: selecting carbon dioxide gas with the purity of more than 99.999% as carbon dioxide reference gas, and selecting a calcium carbonate carbon and oxygen isotope standard substance and a target sample to be measured; and then the stable carbon and oxygen isotopes are determined through a two-way sample introduction method, standard gas does not need to be purchased, the isotope ratio of a sample relative to a standard substance is obtained through conversion application of a formula, finally, the isotope ratio is successfully calibrated to the value of international standard PDB, and the experiment cost is saved. The method can be widely applied to other stable isotope two-way sample introduction methods, principle communication is achieved, and determination can be conducted through the experimental method under the condition that no standard gas exists.

The present invention discloses a method for identifying the origin of basa fish based on stable isotopes, comprising the steps of constructing a sample library of basa fish from the Mekong River, separating and obtaining the fleshy part of each sample, obtaining the tip of the fishbone, and removing the base of the fishbone where the fishbone is connected to the fishbone to obtain the fishbone; and detecting the δ 13 C value, according to the detected fishbone δ 13 C、fishbone δ 13 C and fleshy part δ 13 C respectively constructed the 13 C isotope database, obtain the fishbone δ 13 The 95% confidence interval of C, the standard interval of η2, and the δ 13 C value, and obtain the η2 value of the Basa fish to be tested. If the test value is consistent with the fish bone δ 13 If the 95% confidence interval of C and the standard interval of η2 are met, the origin of the sample is determined to be the Mekong River. Otherwise, the sample to be tested is determined to be falsely labeled. Compared with traditional detection methods, the present invention has high efficiency and accurate results.

The invention relates to a pollution monitoring method and device based on stable isotopes, computer equipment and a storage medium. The method comprises the following steps: acquiring a volatilization fractionation parameter, a dissolution fractionation parameter and an adsorption fractionation parameter of a target pollutant and sample fractionation data corresponding to the target pollutant; constructing an initial evaluation model according to the volatilization fractionation parameters, the dissolution fractionation parameters and the adsorption fractionation parameters; training the initial evaluation model according to the sample fractionation data, and determining a target evaluation model; acquiring local fractionation data of the target pollutant; evaluating local fractionation data according to the target evaluation model, and determining fractionation data of a second target phase state of a target pollutant in a target environment; and determining the mass flux of the target pollutant in the target environment according to the local fractionation data and the fractionation data of the second target phase state, thereby efficiently monitoring the high-density non-aqueous phase liquid pollutant. The method can be adopted.

The invention discloses a coal spontaneous combustion index gas traceability and analysis method based on isotope fingerprints, which comprises the following steps: drilling and sampling each coal seam of a coal mine to prepare desorbed gas, and measuring the abundance ratio of gas isotope to form an isotope fingerprint characteristic spectrum; drawing stable carbon-hydrogen-oxygen isotope fingerprint characteristic spectrums of the coal seam coal sample oxidation process at different temperatures through a temperature programming-gas chromatography-stable isotope mass spectrometer combined system; the method comprises the following steps: collecting underground non-spontaneous combustion area gas, measuring a normal background isotope value, and establishing a background database and stable isotope fingerprint characteristics of various gases to jointly construct a coal mine carbon-hydrogen-oxygen isotope fingerprint database; and applying a physical constraint optimization sub-source quantification mathematical model, and combining a Bayesian depth inversion method to realize rapid matching and high-precision traceability of stable isotope measured data and a fingerprint database. According to the method, tracing analysis of coal spontaneous combustion index gas abnormity in the shallow-buried short-distance multi-coal-seam mining process can be achieved, the coal spontaneous combustion disaster site is positioned, and safe production of a coal mine is guaranteed.

The present invention relates to a recognition model for wild sea cucumbers in seaweed beds based on stable isotopes and a method for constructing the same. The model of the present invention can identify a large number of sea cucumber samples through stable isotope detection and in combination with the parameter calculation method provided in this patent. The model and recognition method of the present invention can be applied to the direction of large-scale, rapid and accurate recognition of wild sea cucumbers in seaweed beds in the aquatic product market, are more easily promoted, and are conducive to the productized development of the wild sea cucumber market standardization.

The invention discloses analysis for restricting silicon isotope composition of an ancient crust based on stable isotope, and the silicon isotope composition of the ancient crust is restricted by analyzing the silicon isotope composition of rock in a green rock zone. Rock in green rock zones of different ages can record the characteristics of the ancient ocean crust, represents the composition of the ancient ocean crust at different time and different places, plays an important role in restricting the silicon isotope composition of the ancient ocean crust, and also has important significance in understanding early mainland evolution. The method comprises the following steps: (1) determining research areas which are six different green rock zones with different ages; (2) determining the silicon content in the green rock zone rock sample; (3) determining the stable silicon isotope composition of the green rock zone rock sample; and (4) comparing Si isotope compositions of the green rock zone rock samples at different age stages, and analyzing the influence of the green rock zone rock samples on the silicon isotope composition of the ancient ocean shell.

The invention relates to the technical field of plasmas, in particular to a medical cyclotron beam centering adjustment method and system. The method comprises the following steps: acquiring a magnetic field sequence, a beam sequence and a current sequence; acquiring a beam oscillation factor according to the lag number difference corresponding to the maximum autocorrelation coefficient of the magnetic field sequence and the beam sequence, the correlation of the magnetic field sequence and the beam sequence and the difference of the maximum autocorrelation coefficient; forming a beam oscillation sequence by the beam oscillation factors, dividing the current sequence after dividing the beam oscillation sequence, fitting a straight line based on the current oscillation sequence and the current sequence, and obtaining the current influence intensity at the current moment according to the difference between the excitation current in all subsequences and the overall excitation current of the current sequence and the mean square error; the proportional term is improved according to the current influence intensity, the excitation current is controlled based on the improvement, and the proportional term is adjusted in real time to optimize the magnetic field control effect. According to the invention, high-efficiency and stable nuclide production efficiency is realized.

The invention discloses a method for rapidly analyzing multiple amino acids in plasma based on sound wave excitation coupled mass spectrometry, which is characterized by comprising the following steps: pretreating a plasma sample by using a protein precipitation method to obtain a loading solution for sample introduction; then, the sample loading solution is subjected to sound wave excitation sample introduction to triple quadrupole mass spectrometry for analysis, the characteristic ion pair peak area of the amino acid and the stable isotope internal standard substance is obtained, and then the multiple amino acids in the plasma sample are subjected to rapid quantitative analysis with a stable isotope internal standard method in combination with a standard curve. According to the invention, a non-contact sample introduction mode is adopted, so that no residue is left in the sample introduction process, the ultrafast collection speed of one sample can be analyzed per second, conventional liquid chromatography consumables such as a chromatographic column and a pre-column are not needed, and the method has the characteristics of simple pretreatment, small sample introduction volume, low matrix effect, high efficiency and rapidness in detection, good stability and reproducibility and the like.

The invention provides a mangrove forest ecological environment monitoring method based on a stable isotope, and the method comprises the following monitoring steps: S1, carbon sink function evaluation: (1) employing a DJIM300RTK + Micro Altum-PT multispectral camera unmanned aerial vehicle and a Thermo Scientific MAT 253 isotope ratio mass spectrometer to carry out evaluation operation, enabling the flight height of the unmanned aerial vehicle to be 80m, enabling the overlapping rate to be 80%, generating an NDVI / NDRE index map, and carrying out the analysis of a carbon sink function; according to the method, the isotope, the unmanned aerial vehicle and the sensor technology are intensively applied, the multi-scale accurate monitoring capability can be achieved, meanwhile, manual sampling is replaced by the unmanned aerial vehicle, the field workload is reduced by 60%, the timeliness of traditional isotope monitoring can be improved by 10-100 times, and the method is suitable for popularization and application. And meanwhile, the comprehensive cost is reduced by 30-50%, and the method is particularly suitable for normalized monitoring requirements of mangrove forest protection areas.

The invention provides a performance evaluation method for a stable isotope mixing model, which comprises the following steps of: collecting and establishing a pollutant source information base containing various types of indexes, determining a standard mixing ratio of each pollution source based on the information base, and creating at least two groups of different prior information sets according to the standard mixing ratio, obtaining various types of indexes in the corresponding mixture according to a standard mixing ratio, further respectively constructing a plurality of data distribution models with various types of indexes, and generating data sets with different sample sizes for each data distribution model, combining the generated data set with corresponding prior information, inputting the combined data set into a to-be-evaluated stable isotope mixing model for operation, recording a test result, and comparing the test result with a standard mixing ratio to obtain the test accuracy of the stable isotope mixing model so as to evaluate the performance of the used model; the method is helpful for systematically evaluating the influence of different factors on a model result, and provides a solid scientific basis for accurate traceability of drainage basin pollution.