24 results about "Comprehensive two-dimensional gas chromatography" patented technology

The invention provides a method for determining hydrocarbon components in mixed aromatic hydrocarbons by using comprehensive two-dimensional gas chromatography-mass spectrometry. The method comprises the following steps: optimizing a target function to make a chromatographic peak signal obtained by a separation model accord with a chromatographic separation process mechanism, fully utilizing complementary information of chromatography and mass spectrometry, improving separation precision, and guiding analysis of complex aliasing peaks; analyzing overlapped chromatographic peaks determined by principal component analysis by adopting the established separation model to obtain a chromatographic peak signal representing a single component after separation, and matching the chromatographic peak signal with a corresponding mass spectrum; in combination with a single chromatographic peak signal and a mass spectrum obtained through separation, according to characteristic fragments and chromatographic retention time in the mass spectrum, component types corresponding to chromatographic peaks are judged, and characterization of the composition of the mixed aromatic hydrocarbon is achieved; a separated single chromatographic peak is subjected to quantitative analysis, the content of each component is calculated by adopting an external standard method in contrast with a standard curve, a quantitative result of the mixed aromatic hydrocarbon sample is obtained, and the measurement precision of the mass fraction of each hydrocarbon component is improved.

The invention discloses a quality mining and evaluation method of a wolfberry characteristic flavor nourishment, and relates to the technical field of food quality analysis and sensory evaluation, and the method comprises the following steps: S1, carrying out non-targeted analysis on the wolfberry characteristic flavor nourishment by adopting headspace solid phase microextraction in combination with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry, and obtaining original abundance data of the volatile compound. According to the quality mining and evaluation method for the Chinese wolfberry characteristic flavor nourishment, accurate identification and quantitative evaluation of key flavor substances in the Chinese wolfberry characteristic flavor nourishment are realized by establishing a flavor contribution potential index model and combining a dual verification mechanism. According to the method, the limitation that only a single chemical component is concerned or actual sensory experience is ignored is solved, and the accuracy and reliability of flavor component screening are improved by integrating multi-dimensional parameters such as instrument response intensity, human olfaction threshold and matrix release characteristics and through cross validation of a gas chromatography-olfaction technology and a standard substance addition experiment.

The present application relates to the technical field of Fischer-Tropsch synthesis wax analysis chemistry, and in particular to a method for detecting oxygen-containing compound components in Fischer-Tropsch synthesis wax by using solid-phase microextraction and comprehensive two-dimensional gas chromatography-mass spectrometry. The method comprises the following steps: first, performing solid-phase microextraction on a to-be-tested wax sample to obtain an extract rich in oxygen-containing compound components; and then using comprehensive two-dimensional gas chromatography-mass spectrometry to qualitatively determine the composition of the oxygen-containing compound components contained in the extract. In the method, the content of the oxygen-containing compound components is less than or equal to 7 wt% based on the total weight of the Fischer-Tropsch synthesis wax. The method has the characteristics of high throughput, high sensitivity and high accuracy, and solves the problems of difficult analysis and separation and difficult qualitative determination of alcohol, aldehyde, ketone, acid, ester and other oxygen-containing compound components in Fischer-Tropsch synthesis wax.

The invention provides a method for analyzing characteristic flavor substances in table vinegar and application of the method, and relates to the technical field of food flavor detection.The method comprises the steps that volatile compounds in the table vinegar are determined through comprehensive two-dimensional gas chromatography-smelling-mass spectrometry, and the characteristic flavor compounds are determined; the content of organic acid and reducing sugar in the table vinegar is determined by high performance liquid chromatography, and the content of characteristic taste compounds in the table vinegar is determined. According to the method, the volatile compounds in the table vinegar are determined by adopting comprehensive two-dimensional gas chromatography and smelling mass spectrometry, and the characteristic odor compounds are positioned and discriminated; the content of organic acid and reducing sugar in the table vinegar is determined by adopting a high performance liquid chromatograph, the content of characteristic taste compounds in the table vinegar is positioned, and discrimination is implemented. According to the method provided by the invention, the characteristic odor substances in the table vinegar can be rapidly and accurately detected, and meanwhile, the taste characteristics of the table vinegar can be objectively reflected.

The invention discloses a method for analyzing chlorinated paraffin in an environment or food sample. Comprehensive two-dimensional gas chromatography-electron capture negative chemical ion source quadrupole mass spectrometry is used for analyzing short-chain and medium-chain chlorinated paraffin in an environment or a food sample. According to the technology, co-outflow components in a complex matrix can be effectively distinguished through orthogonal separation in a unit mass resolution mode, and characteristic ion response information of a target chlorinated paraffin homologue group (C10-C17) can be rapidly and accurately obtained. The detection limit of the method can reach a nanogram / gram (ng / g) level, and the method has high sensitivity, accuracy and precision; according to the method, the conventional C10-C17 chlorinated paraffin in the environment or food sample can be comprehensively covered and accurately quantified, and the actual demand on comprehensive analysis of short-chain and medium-chain chlorinated paraffin in the current environment and food monitoring is effectively met.

The invention provides an organic matter rapid screening and peak generation stability verification method based on a comprehensive two-dimensional gas chromatograph-mass spectrometer. The method comprises the following steps: acquiring sample files of at least two samples; generating a grid file corresponding to each sample file, wherein a first grid of the grid file is used for recording a data condition of a corresponding position in the sample file; combining the grid files to obtain an aggregated grid file, wherein the aggregated grid file comprises a plurality of second grids; target grids are screened in the aggregation grid file, organic matter data of the target grids are obtained, the target grids are second grids with the detection probability larger than the preset probability, and the detection probability is used for representing the probability that the organic matter has features in the corresponding positions in the sample files. According to the method, the organic matter data of different samples are merged, and the target grid is screened according to the data condition of the second grid, so that batch processing of the organic matter data of multiple samples is realized, the processing time is shortened, and the efficiency is improved.

The invention discloses an apple fruit key aroma substance identification method based on sensory omics, and relates to the technical field of aroma substance detection, and the method specifically comprises the following steps: S1, detecting volatile compounds in apple fruits through comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC * GC-QTOFMS); s2, carrying out gas chromatography-olfactory analyzer (GC-O) and odor activity value (OAV) analysis to characterize characteristic aroma compounds in the apple fruits; and S3, determining key characteristic aroma compounds in the apple fruits through aroma recombination and omission experiments. According to the present invention, the aroma substance extraction and enrichment are performed on the apple by using the solid phase micro-extraction, the organic solvent is not required, the operation is simple and easy, the comprehensive two-dimensional gas chromatography-tandem time-of-flight mass spectrometry can comprehensively analyze the volatile compounds in the apple fruit within the short time compared with the common chromatography-tandem mass spectrometry, the peak capacity is significantly improved, and the determination result is significant. The separation and analysis efficiency is obviously superior to that of a traditional gas chromatograph-mass spectrometer.

This invention discloses a wastewater source tracing detection method based on full two-dimensional gas chromatography-mass spectrometry, belonging to the field of environmental monitoring technology. The method includes: establishing a source-end transformation fingerprint chain library based on the connection relationships between parent peak clusters, associated peak clusters, and transformation peak clusters in the peak cluster families corresponding to the source-end sample sequence; obtaining a receptor peak cluster family table; performing a chain comparison between the source-end transformation fingerprint chain library and the receptor peak cluster family table to determine candidate source peak cluster families and overlapping peak cluster families; performing peak cluster family exclusion stripping to generate a confirmed source portion and a set of residual unexplained peak cluster families; merging the residual unexplained peak cluster family set for unknown sources to form an unknown transformation chain; and combining this with the confirmed source portion to output the wastewater source tracing detection results. This invention improves the completeness, specificity, and interpretability of wastewater source tracing detection results.

The invention discloses an organic matter non-targeted all-component screening and quantifying method, and belongs to the technical field of chemical analysis. The technical problem to be solved is to provide a non-targeted all-component screening and quantification method for organic matters, which can qualitatively detect thermally generated organic matters, especially components of human-derived organic matters as comprehensively as possible. According to the technical scheme, the method is characterized in that a solid-phase extraction method is adopted for extracting, purifying and concentrating the thermally-formed organic matter, and non-targeted all-component screening and semi-quantitative analysis are conducted on the thermally-formed organic matter in combination with a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry technology.

The invention relates to a method for distinguishing sesame oil to which exogenous flavors and fragrances are applied from sesame oil to which exogenous flavors and fragrances are not applied, which comprises the following steps: putting the sesame oil to which the exogenous flavors and fragrances are not applied into a sample introduction bottle, and extracting volatile and semi-volatile components in the sesame oil by adopting a headspace solid-phase micro-extraction method, analyzing volatile and semi-volatile components by adopting a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry method to obtain a two-dimensional spectrum of the sesame oil; treating the to-be-detected sesame oil by adopting the same method to obtain a two-dimensional map of the to-be-detected sesame oil, and comparing to judge whether exogenous flavors and fragrances are added into the to-be-detected sesame oil. The two chromatographic columns with different stationary phases are connected in series, so that orthogonal separation is realized, and the separation capacity of the chromatographic system is greatly enhanced. According to the technology, each compound in a complex sample mixture can be subjected to two independent separation mechanisms, and the problems of component co-elution and serious insufficient peak capacity during traditional one-dimensional gas chromatography separation are effectively solved.

The invention belongs to the technical field of aerosol thermal desorption analysis, and discloses a polar organic matter online analysis method and system based on comprehensive two-dimensional gas chromatography and an aerosol thermal desorption analyzer. Comprising four stages of sampling and GC * GC-MS analysis, standard liquid loading and injection, thermal desorption and derivatization and back flushing in the whole working period of a TAG-GC * GC-MS instrument. The TAG-GC * GC-MS system provided by the invention not only overcomes various limitations of a traditional analysis method, but also provides a more accurate and rapid POCs analysis means through an efficient and automatic working process, and provides important technical support for air quality monitoring and pollution source tracking.

A method for determining trace benzene series in Fischer-Tropsch synthesis light naphtha relates to the technical field of analytical test components. The Fischer-Tropsch synthesis light naphtha is added to comprehensive two-dimensional gas chromatography for component detection. The specific temperature rising program is as follows: the initial temperature is 30-35 °C and is held for 15-25 min, then it is heated to 180-250 °C at a rate of 1-5 °C / min and held for 5-15 min. The linear program temperature rising method is used, and the priority range of 1-5 °C / min is adopted to determine the components of trace benzene series in light naphtha. At the same time, the non-polar column and medium-polar column in comprehensive two-dimensional gas chromatography-time of flight mass spectrometry are used to separate naphtha according to boiling point in one dimension and polarity in the second dimension, realizing the separation of trace components in Fischer-Tropsch synthesis light naphtha, improving the accuracy of detection results, and reasonably solving the problem of long detection time in the experimental process and reasonably optimizing the time required for the experiment.

The application discloses a fuel property prediction method and device, equipment and a storage medium, and the method comprises the following steps: analyzing a to-be-tested fuel sample by means of a two-dimensional gas chromatograph to obtain hydrocarbon composition data of the to-be-tested fuel sample, inducing a plurality of key chemical component variables and constructing a component feature vector; performing standardization processing and principal component analysis on the component feature vector to obtain principal components meeting preset conditions and calculating a principal component score vector; inputting the principal component score vector into a trained nonlinear regression prediction model to obtain a predicted value of a physical and chemical property of the to-be-tested fuel sample; wherein the nonlinear regression prediction model comprises linear terms, square terms and interaction terms of the principal component score vector; wherein the square terms and the interaction terms are used to represent the nonlinear effect of the components on the physical and chemical property and the synergistic effect between the components. Thus, the problem of large fuel sample consumption and long test period can be solved, and the fuel property can be accurately predicted.

A method for studying the distribution of aromatics in diesel fuel using two-dimensional gas chromatography (GC) comprises the following steps: S1: Separating the sample to be tested using a GC modulation system to obtain a GC chromatogram; S2: Identifying the detailed compositional information of the sample using the GC chromatogram obtained in step S1, and classifying it into different groups of compounds based on their polarity; S3: Applying the principle of simulated distillation using GC to obtain the distillation curves of the different groups of compounds obtained in step S2; S4: Analyzing the changes in mass yield of different groups of compounds within different fractions of the distillation curves obtained in step S3 to study the component variation patterns during diesel fuel processing and conversion. This invention enables the study of component variation patterns during diesel fuel processing and conversion based on the changes in mass yield of different groups of compounds within different fractions.

The invention discloses a system and a method for realizing two-dimensional and comprehensive two-dimensional gas chromatography, the system comprises a sample injection port EPC system, a four-way valve and a three-way high-frequency electromagnetic valve, one end of a carrier gas pipeline of the sample injection port EPC system is communicated with one end of a sample injection port, the other end of the sample injection port is communicated with one end of a first chromatographic column through a pipeline, and the other end of the first chromatographic column is communicated with the other end of a second chromatographic column through a pipeline; the other end of the first chromatographic column is communicated with a first branch of a four-way joint through a pipeline, a second branch of the four-way joint is communicated with one end of a second damping column through a pipeline, a third branch of the four-way joint is communicated with one end of a first damping column through a pipeline, and a fourth branch of the four-way joint is communicated with one end of a second chromatographic column through a pipeline; and the other end of the second chromatographic column is communicated with the detector through a pipeline. According to the chromatographic system provided by the invention, two independent separation systems are arranged, a two-dimensional gas chromatography or comprehensive two-dimensional gas chromatography test mode can be flexibly selected as required, and the operation is flexible.

The invention provides a method for determining organic pollutants in alkylated greasy dirt water based on comprehensive two-dimensional gas chromatography-mass spectrometry. The method comprises the following steps: acquiring a sewage sample, and carrying out preliminary analysis to obtain two-dimensional retention time data and mass spectrogram data of each component; comparing the two-dimensional retention time data and the mass spectrogram data with a standard compound database to obtain a preliminary qualitative result; calculating the peak area of each component in the preliminary qualitative result, and introducing a standard substance through an internal standard method to obtain a response factor corresponding to each component; correcting the peak area of each component according to the response factor corresponding to each component to obtain corrected peak area data of each component; performing multiple linear regression model optimization on the mass fractions of the components to obtain optimized mass fractions of the components; performing secondary verification on the preliminary qualitative result through a support vector machine to obtain a qualitative result after secondary verification; and outputting the qualitative result after the secondary verification and the mass fraction of each component after the smoothing processing.

The method comprises the following steps: putting a to-be-detected gasoline sample, a potassium bromate-potassium bromide aqueous solution and an inorganic acid aqueous solution into a closed container for reaction to obtain a pretreated gasoline sample; the comprehensive two-dimensional gas chromatograph is adopted for detecting the content of saturated hydrocarbon, aromatic hydrocarbon and olefin in the pretreated gasoline sample, the saturated hydrocarbon, the olefin and the aromatic hydrocarbon can be separated and measured, and the content of gasoline family components can be measured; meanwhile, the measuring speed is high, and the accuracy is high.

The invention discloses a traditional Chinese medicinal material intelligent identification method and system based on cross-modal contrast learning and adaptive attention fusion. The method comprises the following steps: acquiring image data, smell data and text description data of a traditional Chinese medicinal material sample, wherein the smell data can be acquired through laboratory equipment such as an electronic nose, a GC-MS (Gas Chromatography-Mass Spectrometer), a GC-IMS (Gas Chromatography-Mass Spectrometer) and the like or a low-cost sensor array; each modal feature is extracted through encoders such as a visual Transform, a time sequence Transform or a convolutional neural network, a BERT and the like; infoNCE contrast learning is adopted to realize cross-modal semantic alignment of the three-modal features; self-adaptive weighted fusion is carried out through combination of a cross-modal attention mechanism and confidence estimation of uncertainty perception; and multi-task combined learning based on prototype learning predicts the types, the production places and the quality grades of the medicinal materials at the same time. The method further introduces a modal dropout training strategy and a missing modal dynamic completion mechanism to enhance the robustness of the system. According to the method, the three heterogeneous modalities of the image, the smell and the text are deeply fused, various smell acquisition devices are supported, and the method has the advantages of high accuracy, high interpretability and modal loss robustness and is suitable for laboratory high-precision analysis and on-site rapid detection.

This invention provides a method for identifying crude oil types based on two-dimensional gas chromatography-time-of-flight mass spectrometry (GC-TOF-MS). The method includes: dissolving the crude oil sample to be identified using a diluent, then adding a 5α-androstane standard to the system to obtain the crude oil sample; performing chromatographic analysis of the crude oil sample using GC-TOF-MS; denoting the ratio of the sum of the weights of n-alkanes, isoalkanes, monocyclic alkanes, bicyclic alkanes, tricyclic alkanes, tetracyclic alkanes, and pentacyclic alkanes in the crude oil sample to the weight of the crude oil sample to be identified as S; denoting the ratio of the sum of the weights of monocyclic alkanes, bicyclic alkanes, tricyclic alkanes, tetracyclic alkanes, and pentacyclic alkanes in the crude oil sample to the weight of the crude oil sample to be identified as N; and identifying the type of crude oil sample based on the ratio of S to N. This method provides a new approach for the precise identification of naphthenic crude oil and the estimation of naphthenic crude oil reserves.

The invention discloses a multi-dimensional extraction and analysis method of tea aroma in the technical field of food chemistry and analytical chemistry. The method comprises the following steps: firstly, mixing dry tea powder with ultrapure water, oscillating in a constant-temperature water bath, and standing to release fragrance; filling a thermal desorption tube with a specially-made silicon-based mesoporous titanium dioxide-zirconate hybrid nanocage, and adsorbing and enriching aroma components in headspace gas; after adsorption is completed, a thermal desorption pipe is connected into a thermal desorption instrument, and components subjected to thermal desorption are injected into a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry system for analysis after being focused by a cold trap; and finally, processing data by using professional software, extracting multi-dimensional reserved information and mass spectrum characteristics of aroma active compounds, and constructing a four-dimensional fingerprint spectrum for finely characterizing the aroma of the tea leaves. The method disclosed by the invention realizes efficient enrichment, high-resolution separation and multi-dimensional accurate characterization of tea aroma, and is high in sensitivity and good in reproducibility.

The present invention discloses a detection method for determining volatile substances in polypropylene, comprising: (1) Preparation of a solid-phase microextraction fiber coating: i. Dissolve a mixture of MIL-101(Cr) adsorbent and binder in a solvent to form a suspension, and shake and ultrasonically treat the suspension; ii. Immerse the carrier in the suspension and then take it out from the suspension, leaving a layer of coating on the surface of the carrier, and then let the solvent volatilize; iii. Repeat step ii to form a solid-phase microextraction fiber coating on the carrier; Place the polypropylene resin sample in a headspace vial, seal and equilibrate, then insert the solid-phase microextraction fiber coating into the headspace of the headspace vial for extraction, and immediately insert it into the gas chromatography injection port for desorption after taking it out; (3) Use comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry to analyze and detect the extracted volatile substances; (4) Qualitatively and quantitatively analyze the measured volatile substances.

The invention relates to a general diesel fuel construction method and system capable of reproducing engine performance. The method comprises the following step: analyzing the components and content of target diesel oil by adopting comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry and nuclear magnetic resonance technologies. On the basis of n-hexadecane, isohexadecane and 1-methylnaphthalene, a component database is combined, and a model Sur0 is preliminarily constructed. Iterative correction is carried out through deviation functions of three levels of physicochemical characteristics, atomization characteristics and combustion emission characteristics. In each step, the calculation deviation is compared with a preset threshold value, the component proportion is adjusted, optimization models Sur1 and Sur2 are obtained in sequence, and finally a comprehensive alternative fuel model Sur3 capable of accurately simulating target diesel oil is obtained, so that the injection atomization characteristic, the ignition and combustion characteristic, the performance index and various emission characteristics of actual fuel in a cylinder are accurately reproduced; therefore, the method can be used for accurately simulating flow, mixing and combustion characteristics of the diesel engine.

The present invention relates to the technical field of petrochemical analysis and detection, and is a method and device for analyzing diesel components based on a comprehensive two-dimensional gas chromatography-mass spectrometer. The method includes: preprocessing a diesel sample; using a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer to test the preprocessed diesel sample to obtain a test spectrum; performing integration processing and characteristic region division processing on the test spectrum to obtain the substance information corresponding to each component contained in the diesel sample to be analyzed. The above characteristic region division processing is to perform preliminary segmentation and refined segmentation processing according to the characteristic differences corresponding to each component. The data processing logic in the present invention can be constructed as a script or an application and automatically executed by an electronic device, effectively reducing the interference factors in manual analysis and the recognition errors in the analysis by different people, realizing the rapid, comprehensive and quantitative analysis of complex components in diesel, improving the analysis efficiency, and reducing the analysis cost and manual analysis errors.