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

A two-dimensional gas chromatograph with a primary column (14) and dual secondary columns (26, 28) is described. Flow rates in the primary column are less than those in the secondary columns due to an accumulation valve (16). Typically the ratio of second and third column flow capacities combined to primary column flow capacities between about 10 to 1 and 30 to 1. Volatile organic compounds are detected in environmental samples of air water, soil and in body fluids of animals and humans.

The invention discloses a GC*GC (comprehensive two-dimensional gas chromatography) method for hydrocarbons in crude oil or sedimentary organic matters. The method is implemented through directly carrying out analysis on crude oil or sedimentary organic matter samples by using GC*GC-FID (GC*GC-flame ionization detection) so as to obtain data of hydrocarbons (saturated hydrocarbons, aromatic hydrocarbons and the like); and by using GC*GC-TOFMS (GC*GC-time-off-flight mass spectrometer) software and methods and comprehensive two-dimensional gas chromatographic hydrocarbon separation characteristic determinations, carrying out calculation on the data so as to obtain the localization parameters of saturated hydrocarbons and aromatic hydrocarbons. The method disclosed by the invention is validated through taking the GC*GC on crude oil and sedimentary organic matter samples in the Saertu Oilfield in Daqing, the fangzheng fault depression of the peripheral basin, and the Hailer-Tamtsag Basin as examples. The GC*GC method for hydrocarbons in crude oil or sedimentary organic matters disclosed by the invention creates a new method for analyzing hydrocarbons in crude oil or sedimentary organic matters, and has important significances in deep understanding of the oil pool forming process, migration, accumulation, preservation, oil and source rock correlation of crude oil and the geochemical researches on oil pools, exploration of new geochemical indicators of crude oil and the exploration and development of crude oil.

The invention relates to a comprehensive two-dimensional gas chromatography method for quantitatively determining diamondoid hydrocarbons in petroleum sample. The method comprises the steps of (1) preparing to-be-detected sample; (2) analyzing the to-be-detected sample with comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC*GC-TOFMS) to obtain peak information of diamondoid hydrocarbons in the to-be-detected sample; (3) analyzing the to-be-detected sample with comprehensive two-dimensional gas chromatography-hydrogen flame ionization detector (GC*GC-FID) to obtain GC*GC-FID spectrogram of the to-be-detected sample; according to the peak information obtained in step (2), determining peak positions of diamondoid hydrocarbons and D16-adamantane in the GC*GC-FID spectrogram, and obtaining their peak area integration results; and (5) calculating according to internal standard method to obtain quantitative results of diamondoid hydrocarbons. The method is suitable for quantitative determination of diamondoid hydrocarbons in all crude oil and rock extract samples.

The invention relates to a detection method of a nitrogen-containing compound from a rock extract. The detection method comprises the following steps of (1) pre-treating a rock sample to obtain the rock extract; (2) carrying out family component separation on the rock extract, separating and collecting of nitrogen-containing compound fraction, and concentrating the nitrogen-containing compound fraction to use as a to-be-detected sample; (3) preparing a carbazole standard solution and 9-phenyl-carbazole standard solution, measuring a mass chromatogram by using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry to obtain standard curves of the both; and (4) detecting the to-be-detected sample by using the comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry, qualitatively analyzing the nitrogen-containing compound in the to-be-detected sample according to a retention time and characteristic ions, and quantitatively analyzing the nitrogen-containing compound in the to-be-detected sample. The comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry analysis method of the nitrogen-containing compound in the rock extract overcomes the interference problems of overlapping peaks in conventional GC/MS chromatogram; and the qualitative and quantitative results are accurate and reliable.

The invention relates to a screening method of a volatile organic compound in a cigarette filter tip blasting-bead. The method comprises the steps of (1) performing headspace sampling on liquid in the blasting-bead, and combining a combined comprehensive two-dimensional gas chromatography mass spectrometry for carrying out full-scanning analysis on a sample to obtain a full-scanning spectroscopy; (2) automatically comparing chromatographic peaks of the full-scanning spectroscopy and database information through data software to obtain a preliminary qualitative result of each spot; (3) checking the preliminary qualitative result of each spot, combing a peak structure and similarity proportion, optimizing the full-scanning spectroscopy to obtain an optimal spectroscopy, and manually comparing with the database information to obtain an optimal qualitative result; (4) using percentage response for carrying out semi-quantitative analysis on the optimal qualitative result. The method has the advantages of short detection time, simplicity and convenience in operation, high sensitivity, comprehensiveness in screening, and the like, not only can be used for monitoring conventional harmful volatile organic compounds, but also can be used for monitoring if flavor components allowed to be added exceed the limitation or not so as to ensure the safety of blasting-bead products.

The invention discloses a method for determining the chemical composition in white spirit by adopting comprehensive two-dimensional gas chromatography-time of flight mass spectrometry. The method comprises the steps of firstly, diluting a liquor sample to be detected by deionized water until the final alcohol content is 10-15% vol, sucking 8-10mL of diluted liquor sample into a 20mL headspace bottle, and feeding 1-3g of NaCl; after that, enriching the components in the liquor sample by headspace solid-phase micro-extraction; finally, determining by the comprehensive two-dimensional gas chromatography-time of flight mass spectrometry. According to the comprehensive two-dimensional gas chromatography, two chromatographic columns with different polarities are used for carrying out orthogonal separation on the components in the liquor sample; under the action of a modulator, detection is completed by the time of flight mass spectrometry; the method is simple in sample pretreatment way; analytical equipment has the characteristics of being high in flux, sensitivity and accuracy; the problems that the white spirit is complicated in composition, difficult to separate and hard in chemical composition determination can be solved; therefore, an effective way is provided for further analyzing the trace composition of the white spirit.

The invention provides a comprehensive two-dimensional gas chromatography quantitative analysis method of an aromatic sterane compound in petroleum. The method comprises the following steps: fully dissolving and soaking crude oil with a solvent and then filtering to obtain a filtrate; heating to evaporate and concentrate the filtrate to prepare filtrate concentrate; collecting a saturated hydrocarbon group component and an aromatic group component; preparing a saturated hydrocarbon group component sample and an aromatic group component sample and storing the samples at low temperature; analyzing the two samples by using a comprehensive two-dimensional gas chromatograph and a flight time mass detector; performing data processing on spectrograms obtained in the steps to obtain corresponding retention time and peak area integration result. The analysis method can be used for performing full oil analysis and group component analysis; an orthogonal separation system thereof can completely separate the aromatic steroid hydrocarbons from alkane, so that the problems such as common rolling peak, base line interference and insufficient peak capacity can be excellently solved, and the aromatic sterane compound can be accurately measured.

The invention discloses a method for analyzing short-chain chlorinated paraffin in an environment sample by a comprehensive two-dimensional gas chromatography-flight time mass spectrometry, which belongs to the technical field of analytical testing. The method comprises the following steps: 1) performing enrichment extraction on SCCPs in the environment sample; 2) employing a comprehensive two-dimensional gas chromatography-electron bombardment ionization source-low resolution time-of-flight mass spectrometer for detection; 3) employing library searching and a retention time index for determining the nature of the SCCPs component in the sample; and 4) employing an internal standard curve method for determining total amount of SCCPs. The pre-treatment method has the advantages of high extraction efficiency, good purifying effect, and wide application scope; the used apparatus has the advantages of high analysis efficiency, good separating effect, and strong anti-interference capability;the qualitative method is fast and accurate, and does not depend on a standard substance; the quantification method has the advantages of low detecting limit, low sensitivity, wide linearity range, and good repeatability, and the analysis requirement of SCCPs in the practical environment sample can be satisfied.

The invention discloses a method for measuring aroma components in main stream smoke of cigarettes. The method comprises the following steps: (1) placing a filter disc gathered with total particular matters of the main stream smoke of the cigarettes in an extracting solution and extracting, and filtering to obtain filtrate which is a sample solution, wherein the extracting solution is any one of acetone, dichloromethane and hexamethylene; (2) analyzing the sample solution obtained in the step (1) with a comprehensive two-dimensional gas chromatography-gas chromatograph-mass spectrometer; and (3) qualitatively and semi-quantitatively analyzing smoke components by using GC Image software. By the method, a small amount of cigarettes can be directly collected by using a smoking machine standard method to prepare the sample solution, and a complicated sample pretreatment process is not required. The method has the advantages of quick and efficient analysis, small interference, high resolution ratio, large peak capacity, accurate identification and the like, is simple to operate, and can identify various aroma components. Problems of limited peak capacity, insufficient resolution ratio, severe peak overlapping and the like in the traditional chromatography are avoided, and reliability of mass spectrometric identification is improved.

The invention provides a three-online analysis method for the similarity of white spirits. The three-online analysis method comprises the steps of respectively carrying out high-resolution gas chromatography analysis, gas chromatography/mass spectrometry analysis and comprehensive two-dimensional gas chromatography/mass spectrometry analysis on white spirit samples; determining the natures of the peaks of components of the white spirits by means of the gas chromatography/mass spectrometry analysis; carrying out quantitative analysis on an integral result of the peaks of the components of the white spirits by a high-resolution gas chromatographic method; next, carrying out similarity calculation according to a quantitative analysis result; and carrying out similarity comparison and judgment on different batches of white spirits or true and false white spirits. The three-online analysis method for the similarity of the white spirits, provided by the invention, is used for performing separation analysis on the components of the white spirits through a high-resolution capillary gas chromatography; compared with a national standard method, the three-online analysis method has the advantages that the separated components are increased doubly and more detailed component information is provided. The reliability of the three-online analysis method is greatly superior to that of nature determination of a traditional mixed standard sample for a gas chromatography, the unique components of different kinds of white spirits can be identified, and detailed component analysis can be provided through identifying the true and false white spirits by a similarity calculation method and combining a comprehensive two-dimensional gas chromatography/mass spectrometry analysis method.

The invention discloses a method for determining crude oil cracking degree. The method comprises the following steps: S1, recognizing and identifying ethyldeamantadine series and methyl diamantine series compounds in multiple crude oil samples by utilizing a comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer GC*GC-TOFMS, thus obtaining peak information of each compound; S2, performing quantitative analysis on the ethyldeamantadine series compounds, thus obtaining contents of the ethyldeamantadine series and methyl diamantine series compounds; S3, fitting a relational expression between the contents of the ethyldeamantadine series compounds and (4-+3-) methyl diamantine; S4, building a relationship between (4-+3-) methyl diamantine and the crude oil cracking degree; and S5, determining the crude oil cracking degree. The method disclosed by the invention can determine the crude oil cracking degree only by virtue of a small amount of crude oil sample, a deepoil and gas cracking window is judged, further quantity of deep oil and gas resources is evaluated, and exploration and development are guided.

The invention discloses a method for analyzing constituents of white spirit, which is capable of detecting more constituents. The method comprises the steps of: carrying out condition normalization on an SBSE (stir bar sorptive extraction) stir bar by a thermal desorption apparatus, then absorbing target matters in a white spirit sample by the SBSE puddler, transferring the SBSE stir bar to a desorption chamber of the thermal desorption apparatus, desorbing the absorbed target matters to a program heating sample inlet through the thermal desorption apparatus, providing the target matters in GC*GC-TOFMS (comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometer) to separate and analyze via the program heating sample inlet, wherein the used SBSE stir bars respectively are the SBSE stir bar with a polydimethylsiloxane absorption layer and the SBSE stir bar with a polyethylene glycol modified organic silicon absorption layer. The result is accurate and reliable; the sensitivity is high, and the method can be used for analyzing the constituents of all white spirit, is particularly suitable for analysis of a micro-constituent of which the mass percentage is 0.01-0.1%, and also can be used for analysis of a trace constituent of which the mass percentage is smaller than 0.01%.

A method to simulate distillation of a petroleum stream by comprehensive two-dimensional gas chromatography including the step of separating said petroleum stream with a two-dimensional gas chromatograph to determine polarity as a function of temperature, and integrating vertically the two-dimensional gas chromatograph at a given temperature to determine signal intensity as a function of temperature.

A method for detecting substances or mixtures of substances within a sample in an apparatus for comprehensive two-dimensional gas-chromatographic analysis according to the present invention, comprising the steps of:

• • subjecting the sample to a first separation within a first capillary column;
  • modulating in time the effluents from the first column by means of the subdivision into adjacent fractions of the effluents from the first column and subsequently sending each fraction into a second capillary column, the modulation of the effluents being periodic with a first modulation frequency f₁ of the sample;
  • separating each of the fractions in the aforesaid second capillary column; and
  • detecting, at the end of the second capillary column, the effluents by means of periodic sampling by discrete time points at a second frequency f₂.

The method moreover envisages the step of generating the first frequency f₁ of modulation and the second frequency f₂ of sampling in such a way that sampling by discrete points downstream of the second column will be in phase with the modulation of the effluents from the first column.

The invention discloses a method for determining a phase state of an oil-gas reservoir. The method comprises step S1 of utilizing a comprehensive two-dimensional gas chromatography - time-of-flight mass spectrometer GC x GC- TOFMS to recognize and identity ethyl Noradamantane series compounds in a plurality of crude oil samples, thereby obtaining peak information of each compound; step S2 of quantitatively analyzing the ethyl Noradamantane series compounds to obtain contents of the ethyl Noradamantane series compounds; step S3 of fitting a relation between the content of the ethyl Noradamantane series compounds and gas-oil ratio of an oil reservoir; step S4 of establishing a relationship between the gas-oil ratio of the oil reservoir and the phase state of the oil-gas reservoir; and step S5 of determining the phase state of the oil-gas reservoir. The invention determines the phase state of the oil-gas reservoir by utilizing content of ethyl Noradamantane , thereby providing a new indexfor determining the phase state of a deep-level oil-gas reservoir, and providing a new pattern of solution to oil-gas resource evaluation.

The invention discloses a method for detecting ester components in orange juice by online solid-phase micro-extraction (online-SPME) and comprehensive two-dimensional gas chromatography-quadrupole mass spectrometry (Comprehensive 2D GC/qMS). The method comprises the following steps: enriching ester components in an orange juice sample by online-SPME and detecting by comprehensive 2D GC/qMS; carrying out qualitative analysis on a detected compound in a manner of combining retention indexes and an NIST spectral library; and accurately quantifying chromatography overlapping peaks of components, which can not be separated by comprehensive 2D GC/qMS, by section convolution. According to comprehensive 2D GC/qMS, two chromatographic columns with different polarities are used to carry out orthogonal separation on the ester components and then the separated components enter qMS under the effect of a modulator-demodulator to be detected; the retention time indexes and the NIST spectral library are combined to carry out qualitative analysis; a section convolution technology is used for quantifying the chromatography overlapping peaks accurately. The method has the characteristics of high throughput, high sensitivity and high accuracy; the problems that the analysis and the separation of ester components of orange juice are difficult and the qualitative analysis is difficult are solved.

The present invention is an improvement to two-dimensional comprehensive gas chromatography. The improvement is a one valve switching modulator connecting the two separation columns. The valve includes either a two position eight-port valve or a two position twelve-port valve, and two transfer lines.

The invention discloses a device and a method for switching between comprehensive two-dimensional gas chromatography and one-dimensional gas chromatography. The switching device comprises a gas supplement module, a switching switch, first to fourth interfaces, a first air resistor and a second air resistor, wherein a first end of the second interface is connected with a first end of the second airresistor through a first pipeline; a second end of the second air resistor is connected with a first end of the third interface through a second pipeline; the outlet of the gas supplement module is connected with the switching switch through a third pipeline; a first outlet of the switching switch is connected with the first pipeline on a first node through a fourth pipeline; a second outlet of the switching switch is connected with the first pipeline on a second node through a fifth pipeline; two ends of the first air resistor are connected with the fourth pipeline and the fifth pipeline respectively; a first end of the first interface is connected with the first pipeline between the first node and the second node through a pipeline; a first end of the fourth interface is connected withthe second pipeline through a pipeline. The device and the method can automatically switch between the comprehensive two-dimensional gas chromatography and the one-dimensional gas chromatography, andthe demand of alternatively using the comprehensive two-dimensional gas chromatography and the one-dimensional gas chromatography with one instrument is met.

A modulator for simply providing fast and precise sampling of a chromatographic peak eluting from a first column into a second column of a comprehensive two-dimensional gas chromatograph, where the modulator includes a planar component containing a first gas passage for connecting a carrier gas source to the second separation column, a second gas passage for connecting the first separation column to an exhaust outlet, a connecting gas passage between the first and second gas passages, and two individually controllable open/close valves arranged in parallel connection in the first gas passage between its connection to the carrier gas source and the branch-off of the connecting gas passage, and where the gas passages and valves are formed in the planar component by micromachining.