18 results about "Quantitative analysis (chemistry)" patented technology

The invention discloses a pesticide residue quantitative analysis system based on Raman spectrum, and relates to the technical field of analytical chemistry and detection.The pesticide residue quantitative analysis system comprises an acquisition module, a processing module, an analysis module and a regulation and control module, the acquisition module is used for acquiring samples and Raman scattering signals, converting the Raman scattering signals into original spectrum data and transmitting the original spectrum data to the processing module; calibrating the original spectrum data, acquiring calibrated spectrum data, transmitting the calibrated spectrum data to an analysis module, comparing the calibrated spectrum data with a pesticide standard spectrum library, outputting a quantitative analysis result of pesticide residues, transmitting the quantitative analysis result to a regulation and control module, storing the pesticide standard spectrum library and the calibrated spectrum data, and correcting sample detection deviation by using the calibrated spectrum data. And through the regulation and control unit, full-process automatic operation from sample processing to result output is realized, the detection reliability is improved through spectrum compensation and characteristic peak comparison, efficient automation is realized through task scheduling and time sequence synchronization, and hardware fault tolerance, authority management and multi-scene adaptation capabilities are realized.

The present application relates to the field of analytical chemistry, in particular to a method for detecting ten tobacco alkaloids in soil, which uses sodium hydroxide solution and acetonitrile to extract alkaloids in a soil sample, and uses ultra-high performance liquid chromatography-triple quadrupole mass spectrometry to analyze and detect nicotine, nornicotine, myosmine, pseudotropine, anatabine, anabasine, 2,3'-bipyridine, noranatabine, N-methyl pseudotropine and nornicotine, and uses an internal standard method for quantitative analysis. The present application uses sodium hydroxide solution as an alkaloid eluent and acetonitrile as an extractant, which reduces the amount of solvent used, optimizes the operation process, uses sodium chloride to separate the organic phase and the aqueous phase, improves the sample pretreatment efficiency, uses ultra-high performance liquid chromatography-triple quadrupole mass spectrometry to target analysis of 10 tobacco alkaloids, greatly improves the detection sensitivity, and has strong quantitative ability in targeted analysis.

This invention belongs to the field of environmental chemistry and relates to a method for quantitatively analyzing the concentrations of cystine and cysteine ​​in a mixed solution. Based on the theoretical characteristics of the reaction between the disulfide bond in cystine, a representative amino acid, and the thiol group in cysteine, and persulfate, this invention expands the detection capability of the traditional 5,5-dithio-bis-(2-nitrobenzoic acid) (DTNB), providing support for the quantitative analysis of cystine and cysteine ​​concentrations and the study of their transformation processes.

The invention belongs to the technical field of environmental analytical chemistry, and particularly relates to a separation and purification and high-throughput target quantitative analysis method for multiple types of environmental pollutants in a complex matrix biological sample. The method comprises the following specific steps: S1, carrying out ultrasonic extraction on a biological sample to obtain an extracting solution; s2, performing dispersive solid-phase extraction and purification treatment on the extracting solution to obtain a solution to be detected; s3, determining the environmental pollutants in the liquid to be detected by adopting a selected ion scanning mode of the gas chromatograph-mass spectrometer. The pretreatment method disclosed by the invention can effectively reduce complex matrix interference of the biological sample, and can quickly and efficiently perform high-throughput target analysis on multiple types of environmental pollutants in the biological sample; the method disclosed by the invention is low in detection limit and capable of realizing trace detection of a biological sample; the invention provides a new method for researching the occurrence condition of the environmental pollutants in the 17 marine organisms in Liaoning Bay, and has important significance for the progress of environmental science.

The invention belongs to the technical field of analytical chemistry, and particularly relates to a multifunctional chiral selection reagent solution (CSS) and application of the multifunctional chiral selection reagent solution. More specifically, the invention relates to a multifunctional chiral selection reagent solution for chiralMS (chiralMS) analysis, and the solution is prepared from CuCl2, D-Phe, L-Ph-d5 and D-or L-3'and / or 4 'hydroxyl substituted Kelin lactone. According to the present invention, the on-line non-covalent derivatization can be performed on the enantiomers in the complex system sample by using the multifunctional chiral selection reagent solution and by using the post-column injection liquid chromatography-mass spectrometry (post-column injection liquid chromatography-mass spectrometry / MS, PCI-LC-MS / MS) system so as to achieve the qualitative and quantitative analysis of the enantiomers and the rapid screening of the chiral selection reagent (CS).

The invention discloses a single-molecule sensor based on STM-BJ and application of the single-molecule sensor, and belongs to the technical field of analytical chemistry. On the basis that 1, 3-bis (pyridine-4-yl) propane-diketone interacts with alcohols under the conditions of applying negative bias and applying a sodium sulfate aqueous solution to form a supramolecular junction, a supramolecular strategy is introduced into a gap between a probe and a sample table in STM-BJ, and specific single molecule detection of alcohol molecules is realized by using a negative bias working mode of STM. Compared with other traditional research means, the method provided by the invention not only can accurately identify alcohol molecules, has high sensitivity, but also can realize quantitative analysis of alcohols.

The invention provides an analysis method for chemically and quantitatively separating carbide phases M6C and MC in high-speed steel, and belongs to the technical field of metallurgical analysis and physical and chemical phase analysis. According to the method, the M6C phase and the MC phase are quantitatively extracted and separated, so that the content and the element composition of each phase are accurately measured. The method comprises the following steps: firstly, extracting all carbide phases in the steel through an electrolysis technology, then selectively dissolving and separating the carbide phases by using various separating solutions based on the difference of the different carbide phases in chemical properties, and carrying out reflux treatment on the obtained M6C and MC phases by using a 5% complexing agent and a 20% weak oxidant solution, so that the M6C phase is selectively dissolved while the MC phase is kept insoluble, and collecting, filtering and cleaning to obtain a pure carbide MC phase. Respectively dissolving the separated precipitates, fixing the volume, and measuring by adopting an inductively coupled plasma spectrometry. According to the method, accurate quantitative analysis of carbide phases M6C and MC in high-speed steel is realized, the technical problem that the carbide phases are difficult to separate is solved, and a reliable method is provided for material research and quality control of the high-speed steel.

The application belongs to the field of environmental analysis chemistry and mass spectrometry, and particularly relates to a carboxylic acid compound targeted-non-targeted collaborative analysis method based on stable isotope labeled aniline derivative reagent and double library system. The method uses aniline and d5-aniline as derivative reagents to perform amide derivative treatment on carboxylic acid compounds, and realizes high-sensitivity detection in combination with liquid chromatography-mass spectrometry. Further, a self-built double library system containing a derivative spectrum library and a non-derivative spectrum library is constructed, and in combination with targeted quantification and non-targeted screening, the collaborative identification and quantitative analysis of known and unknown carboxylic acid compounds are realized. The actual PM2.5 sample is analyzed by using the method, 52 kinds of carboxylic acid compounds are detected, 13 of which are known carboxylic acids with standard samples, and 39 of which are carboxylic acids without standard samples but verified and confirmed by the double library collaborative verification, which verifies the effectiveness of the application.

The invention relates to the field of analytical chemistry, and particularly discloses a gas chromatographic analysis method of trifluoroacetic acid and application of the gas chromatographic analysis method. The method aims to solve the problems of inaccurate trifluoroacetic acid content analysis result and poor reproducibility caused by interference of associated volatile strong acid impurities in a sample in the prior art. The method comprises the following steps: directly sucking a trifluoroacetic acid sample to be detected by using a microinjection needle, injecting the trifluoroacetic acid sample into a gas chromatograph equipped with a hydrogen flame ionization detector for analysis, and calculating the mass percentage content of trifluoroacetic acid by adopting an area normalization method. The core of the method is that a special capillary chromatographic column with ON-TFA as a stationary phase is adopted, and the sample size, the carrier gas flow, the temperature of a sample inlet and specific temperature programming conditions are controlled. According to the method, complex sample pretreatment is not needed, trifluoroacetic acid and impurities can be effectively separated, rapid, direct, high-accuracy and high-reproducibility quantitative analysis is achieved, and the method is suitable for production quality control, purity identification and solvent recovery of trifluoroacetic acid products.

The application discloses a pesticide residue quantitative analysis system based on Raman spectrum, relates to the field of analytical chemistry and detection technology, and comprises a collection module, a processing module, an analysis module and a regulation and control module.The collection module is used for collecting samples, obtaining Raman scattering signals, converting the Raman scattering signals into original spectrum data, transmitting the original spectrum data to the processing module, calibrating the original spectrum data, obtaining calibrated spectrum data, transmitting the calibrated spectrum data to the analysis module, comparing the calibrated spectrum data with a pesticide standard spectrum library, outputting quantitative analysis results of pesticide residues, transmitting the quantitative analysis results to the regulation and control module, storing the pesticide standard spectrum library and the calibrated spectrum data, and using the calibrated spectrum data to correct sample detection deviation.The application realizes full-process automatic operation from sample processing to result output through a regulation and control unit, improves detection reliability through spectrum compensation and characteristic peak comparison, realizes efficient automation through task scheduling and time sequence synchronization, and has the abilities of hardware fault tolerance, permission management and multi-scene adaptation.

The present application belongs to the field of environmental analysis chemistry, and discloses a method for evaluating the performance of a gas chromatograph mass spectrometer. The evaluation method integrates multi-index instrument performance evaluation standard substances, and realizes accurate evaluation of the performance of the gas chromatograph mass spectrometer based on the standard curve of the target substance registered in the database. The evaluation method established by the present application can comprehensively evaluate the influence of instrument components such as the chromatographic column, the sample inlet and the mass spectrometer on the qualitative and quantitative analysis of target compounds through single injection, thereby saving the cost required for purchasing standard substances, manpower and time required for instrument testing, and having the advantages of high efficiency, convenient operation and low cost. The present application provides technical support for monitoring and controlling new pollutants, and has a wide application prospect.

The application discloses a method for detecting micro-nano plastics in water by using magnetic nickel sponge combined with thermal cracking mass spectrometry, and belongs to the technical field of environmental analysis chemistry and micro-nano plastic pollution detection. The method comprises the following steps: silanization treatment of ferroferric oxide, using three-dimensional porous nickel sponge as a carrier and chitosan as a crosslinking agent to form a magnetic nickel sponge material; placing the magnetic nickel sponge material in a sample to be detected for micro-nano plastic separation and enrichment, and then placing the magnetic nickel sponge adsorbing the micro-nano plastics in a thermal cracking chamber for thermal cracking, and combining a small-sized mass spectrometer to realize qualitative and quantitative analysis of the micro-nano plastics; the magnetic nickel sponge material has strong micro-nano plastic adsorption capacity, is resistant to high temperature and has no background interference, and is especially suitable for thermal cracking analysis; the analysis method is fast and highly sensitive, realizes rapid thermal cracking and accurate qualitative and quantitative analysis of the micro-nano plastics, is suitable for various environmental water bodies such as drinking water, lake water, river water and high-salt seawater, is environmentally friendly and cost-controllable; the magnetic nickel sponge material can be repeatedly used, thereby reducing the cost of consumables and meeting the green analysis chemistry concept.

The invention belongs to the technical field of analytical chemistry, and particularly relates to a vinyl chloride product produced by an ethylene method and a trace impurity detection method. According to the method disclosed by the invention, a vinyl chloride liquid sample is instantly and completely vaporized and integrally transferred to a gas chromatograph through flash evaporation sample injection, so that the liquid vinyl chloride sample is completely vaporized and integrally transferred; liquid vinyl chloride is subjected to flash evaporation and then enters a gas chromatography 1mL sample injection six-way valve, volume quantification is ensured, vinyl chloride and impurities are effectively separated through the separation effect of a gas chromatography column, only 1-3 characteristic ions of target impurities are monitored in an SIM mode through the advantages of high sensitivity and low detection limit of a quadrupole mass spectrometry detector, interference of other ions in a matrix is eliminated, and the detection accuracy of the target impurities is improved. The detection method has the advantages that the signal-to-noise ratio is greatly increased, high-sensitivity and high-selectivity quantitative analysis on trace and even trace (g / g level and even lower) impurities in vinyl chloride is realized, rapid screening of vinyl chloride products and identification of process abnormality are realized, and the detection method has universality.

This invention relates to the technical field of analytical chemistry, specifically to an analytical detection method for benzo[a]pyrene in nicotine bags, comprising the following steps: placing the nicotine bag sample in a container, adding an internal standard and a cyclohexane solution to the container to obtain a mixture, and performing shaking extraction, centrifugation, and filtration, taking the supernatant as the test solution; wherein the internal standard includes benzo[a]pyrene-D12; detecting the test solution using gas chromatography-tandem mass spectrometry, and performing quantitative analysis of benzo[a]pyrene based on the response signal of the internal standard. This invention, through the selection of a specific internal standard and cyclohexane pretreatment, can be specifically used for the quantitative analysis of benzo[a]pyrene in nicotine bags, and has the advantages of efficient and simple pretreatment and effective overcoming interference from complex matrices.

The invention belongs to the technical field of analytical chemistry, and particularly relates to a method for simultaneously detecting catechin, alkaloid and amino acid. Comprising the following steps: 1, pretreatment: adding a to-be-detected sample into an extracting solution for ultrasonic extraction, centrifuging, and diluting the centrifuged supernatant as a to-be-detected solution; wherein the extracting solution is an aqueous solution of formic acid with the volume content of 0.1% and methanol with the volume content of 50%; 2, detecting on a machine: carrying out quantitative analysis by adopting a high performance liquid chromatography-high resolution mass spectrometer; wherein a chromatographic column adopted by the high performance liquid chromatography is a Hypersil GOLD chromatographic column, and the specification of the chromatographic column is 150 * 2.1 mm to 1.9 [mu] m; a mobile phase adopted by the high performance liquid chromatography comprises a water phase and an organic phase, the water phase is a formic acid aqueous solution with the volume content of 0.1%, and the organic phase is a methanol solution; and 3, data processing: carrying out quantitative analysis on each component to be detected by adopting a standard calibration method. According to the method, the pretreatment method is simple, and catechin, amino acid and alkaloid with large polar span of three substances are rapidly and effectively separated.

This invention belongs to the field of environmental analytical chemistry and mass spectrometry, specifically relating to a targeted-non-targeted synergistic analysis method for aldehyde compounds based on stable isotope-labeled APMP derivatization reagents and a dual-library system. This method synthesizes d0 and d3 isotope-labeled APMP reagents to derivatize aldehyde compounds, and combines this with liquid chromatography-mass spectrometry (LC-MS) to achieve highly sensitive detection. Furthermore, a self-built dual-library system containing both derivatized and non-derivatized libraries is constructed, combining targeted quantification and non-targeted screening to achieve synergistic identification and quantitative analysis of known and unknown aldehyde compounds. Isotope internal standard correction and library matching verification improve the accuracy and reliability of the detection. This invention overcomes the limitations of traditional methods in terms of limited detection coverage and insufficient non-targeted quantitative analysis capabilities, making it suitable for high-throughput analysis of aldehyde compounds in complex environmental samples.

The invention belongs to the technical field of analytical chemistry, and particularly relates to a preparation method of a laser-induced breakdown spectroscopy solid target and a solid-phase laser-induced breakdown spectroscopy rapid detection method of salt lake brine. The method comprises the following steps: mixing a salt lake brine sample with sodium carbonate to obtain a carbonate precipitate suspension; and filtering the carbonate precipitation suspension by using a functional modified film to obtain the laser-induced breakdown spectroscopy solid target. According to the method, the concentration of Li ions in the salt lake brine is detected by adopting a laser-induced breakdown spectroscopy solid target. According to the method, liquid sample analysis is converted into high-stability solid target analysis, rapid and high-sensitivity detection and quantitative analysis of mg / L level lithium ions in the salt lake brine are achieved, the RSD is about 2.0% within the interval of 20-50 mg / L, the detection stability and sensitivity under the liquid-phase LIBS condition are remarkably improved, and the method is suitable for on-site rapid monitoring of the salt lake.

The invention provides a method for detecting the quality of a turmeric extract, and belongs to the technical field of medicine detection.The method comprises the steps that the turmeric extract is taken to be prepared into a test solution, then gradient elution is conducted through acetonitrile (A) and 0.08-0.12 wt% of formic acid aqueous solution (B), then quantitative analysis of multiple components by single marker, an external standard method or a standard curve method is adopted, and the quality of the turmeric extract is detected. And calculating the contents of curcumin, demethoxycurcumin, bisdemethoxycurcumin and dihydrocurcumin in the turmeric extract. According to the method, synchronous quantitative analysis of four effective components including demethoxycurcumin, bisdemethoxycurcumin and dihydrocurcumin is realized, so that multiple technical effects of multi-component accurate control, detection efficiency improvement and standard substance dosage reduction are achieved, the detection cost is effectively reduced, the consumption of chemical reagents is reduced, and the method is suitable for industrial production. The development requirements of green analytical chemistry are met.