712 results about "Capillary column" patented technology

A temperature programmed low thermal mass fast liquid chromatography system capable of high throughput and low power consumption includes a straight or curved short reloadable low-mass tubular heater with a capillary column extending inside. If the capillary column is long enough, it is coiled to form a coiled capillary LC column (the length of which does not exceed 0.2 m-1.0 m) packed in a singular module package with a heating wire and a temperature sensing wire extending along and in proximity to the LC capillary column. A tubular heater, e.g. a steel tubing, incorporates the LC capillary column, along with the heating wire and the temperatures sensor and is coiled to form a miniature power saving LC module which may be attached outside a chromatography oven. Capillary lengths extend inside the oven between the inlet and outlet of the LC column module and mobile phase source and detector, respectively. An electronic temperature control block is positioned outside the oven cavity and controls the heating of the capillary LC column, as well as other heated zones in the system.

An apparatus for use in controlling the temperature of one or more substances passing through one or more microfluidics channels in an analysis device is set forth. The apparatus comprises a heating unit having first and second surfaces. The first surface of the heating unit is constructed so that it is at least partially exposed for cooling of the heating unit. The apparatus also comprises a thermally conductive medium that is disposed proximate the second surface of the heating unit. The one or more microfluidics channels are disposed in the thermally conductive medium. In one embodiment, the one or more microfluidics channels are in the form of a plurality of capillary columns, such as those used in instruments for capillary electrophoresis. Each capillary columns is substantially surrounded by the material forming the thermally conductive medium. In another embodiment, the thermally conductive medium, along with the corresponding plurality of capillary columns, can be easily disengaged from the heating unit in a non-destructive manner thereby allowing the heating unit to be reused.

The invention discloses a chiral analysis method for nicotine in tobacco juice of an electronic cigarette. The chiral analysis method comprises the steps of diluting the tobacco juice of the electronic cigarette by a methyl alcohol/methyl tertiary-butyl ether solution, analyzing S-(-)-nicotine and R-(+)-nicotine in the tobacco juice of the electronic cigarette by using a chiral stationary phase capillary column mthrough a gas chromatograph-mass spectrometer, performing chiral analysis on the S-(-)-nicotine and the R-(+)-nicotine by comparing the retention time of a chromatographic peak and characteristic ions of nicotine in a standard sample with the retention time of a chromatographic peak and characteristic ions of nicotine in an electronic cigarette tobacco juice sample, and normalizing areas of quantitative ion peaks of the S-(-)-nicotine and the R-(+)-nicotine to quantify the proportions of the S-(-)-nicotine and the R-(+)-nicotine to the total nicotine. The chiral analysis method has the advantages that the nicotine in the tobacco juice of the electronic cigarette is separated by a chiral stationary phase capillary column, so that the S-(-)-nicotine and the R-(+)-nicotine in the nicotine can be better separated, and accurate and quantitative analysis on the nicotine can be realized. The sample treatment is simple and convenient; the chiral analysis method is low in detection limit, high in sensitivity, high in reproducibility, accurate in quantification and suitable for chiral analysis on the nicotine in a large batch of electronic cigarette tobacco juice samples.

The invention discloses a method for simultaneously measuring multiple residues of organic chloride and pyrethroid pesticides. The method comprises the following working procedures: crushing a tobacco sample until grain diameters are less than 450 mu m; adding 10 to 20ml of extracting solution and internal standard solution into every program of tobacco sample; extracting the mixed solution by using ultrasonic wave; filtering the mixed solution by using a funnel filled with anhydrous sodium sulfate to obtain the extracting solution; adding the extracting solution into a Florisil solid extraction column for extracting and eluting; collecting an eluent; analyzing the eluent by using a gas chromatograph, wherein the analysis comprises the following conditions: adopting an Elite 5MS capillary column, high-purity N2 as a carrier gas, a constant flow mode in which the flow rate is 0.5 to 1.5 ml/min, a sample inlet temperature of between 280 and 320 DEG C, a detector temperature of between 330 and 370 DEG C, splitless sampling in which the sampling volume is between 1 and 2 mu L, and an initial temperature of 100 DEG C which rises from 100 to 180 DEG C at a speed of 8 DEG C/min, is kept for 4 minutes, rises from 180 to 270 DEG C at the speed of 5 DEG C/min and is kept for 15 minutes until all sample flows out completely; and determining the nature of the sample by using the retaining time of a standard sample and quantifying by using an internal standard method. In the method, ultrasonic wave is adopted for extracting and a solid extraction column is adopted for purifying, so that the method has the advantages of operating step simplification, high work efficiency, good purification effect, capability of simultaneously measuring multiple residues of 25 kinds of pesticides including 17 organic chloride pesticides of hexachlorocyclohexane, DDT and the like, seven pyrethroid pesticides such as fenpropathrin and the like, and one plant growth regulator.

The invention discloses a method for analyzing decomposition products of SF6 in electric equipment. The method comprises the following steps: sampling; and analyzing and detecting a sample with a chromatograph, wherein the detection part of the chromatograph comprises a thermal conductivity detector (TCD) and fission-product detector (FPD) which are in serial connection, the chromatographic column adopts capillary column GS GasPro, and all the pipelines of the chromatograph must be passivated. By using the invention, the decomposition products such as SO2F2 in SF6 can be accurately analyzed; and by analyzing the decomposition impurities such as SO2F2, the internal operating condition of the SF6 gas isolating device can be effectively judged and the electric equipment failure can be successfully judged.

The present invention concerns a new and useful structure for forming a capillary tube, e.g. for gas chromatography, and methods for forming the capillary tube are described. The capillary tube comprises a tube structure, and a deactivated surface-bonded sol-gel coating on a surface of the tube structure to form a stationary phase coating on that surface of the tube structure. According to the present invention the deactivated stationary phase sol-gel coating enables separation of analytes while minimizing adsorption of analytes on the separation column structure.

The present invention discloses filter paper sheet gas chromatography-mass spectrum analysis process of organic acid/amino acid metabolic product in urine. The process includes elution of urine collected with filter paper, oximation reaction, extraction, methyl silane derivation, and united detection with chromatographic instrument and mass spectrograph. The process of the present invention is superior in that the filter paper collection of urine favors remote analysis of genetic metabolic diseases; the oximation reaction processing favors alpha-ketonic acid detection for diagnosis of branched chain ketonic acid metabolic disorder; the extraction has high recovery rate of organic acid/amino acid metabolic product, high repeatability, less chromatographic impurity peaks and no pollution to chromatographic capillary column and mass spectrographic ion source; and the united detection is suitable for screening analysis of great amount of samples.

The present invention relates to a method for separating biological macromolecular component by using two-dimensional or multidimensional capillary electrophoresis and its interface. The biological macromolecular component undergone the process of one-dimensional capillary electrophoresis separation can be passed through the interface and fed into two-dimensional capillary electrophoretic separation operation to implement two-dimensional capillary electrophoresis, the small molecular substance can be diffused and freely permeated through the hollow fibre in the interface and can obtain balance in it, and when the described biological macromolecular component is flowed through the interface, the buffer solution containing low molecular substance can be on-line added/removed into the hollowfibre in the interface.

A multi-capillary column pre-concentration trap for use in various chromatography techniques (e.g., gas chromatography (GC) or gas chromatography-mass spectrometry (GCMS)) is disclosed. In some examples, the trap can include a plurality of capillary columns connected in series in order of increasing strength (i.e., increasing chemical affinity for one or more sample compounds). A sample can enter the trap, flowing from a sample vial to a relatively weak column to the relatively strongest column of the trap by way of any additional columns included in the trap, for example. In some examples, the trap can be heated and backflushed so that the sample exits the trap through the head of the relatively weak column. Next, the sample can be injected into a chemical analysis device for performing the chromatography technique (e.g., GC or GCMS) or it can be injected into a secondary multi-capillary column trap for further concentration.

The invention discloses a chiral porous organic case quartz capillary column used for optical isomer splitting. A preparation method for the chiral porous organic case quartz capillary column comprises the following steps: firstly, synthesizing a chiral porous material CC3-R or CC3-S; filling a quartz capillary column with a sodium hydroxide solution, keeping for 2 hours, then, flushing with deionized water, hydrochloric acid and deionized water in sequence, and introducing dry nitrogen gas; preparing a synthesized chiral porous organic material into a dichloromethane solution, mixing the dichloromethane solution with a 4.5mg/mL OV-1701 dichloromethane solution in an isovolumetric manner to obtain a mixed solution; filling the processed quartz capillary column with the mixed solution and preparing a required chromatographic separation column by adopting a static column preparing method. The chromatographic separation column has excellent chiral dismounting performances on a plurality of optical isomers including alcohol, amine, dihydric alcohol, alcohol amine, amino acid methyl ester, organic acid, halogenated hydrocarbon, ester, ether, an epoxy compound, ketone, sulfoxide and the like.

The invention discloses a low temperature gas chromatography system, a low temperature gas chromatography method and a low temperature gas chromatography device of a volatile organic compound in atmosphere. The method comprises the steps of collecting a gas sample, and carrying out ozone removal treatment, water removal treatment and enrichment treatment on the collected sample; after the enrichment treatment, separating the sample, and detecting; analyzing the treatment detection result. The low temperature gas chromatography device of the volatile organic compound in the atmosphere adopts a temperature control unit to realize the water removal treatment and the enrichment treatment of the atmospheric sample as well as the low-temperature efficient separation of a single capillary column for low hydrocarbon at the same time. The system, the method and the device are simple and reliable, and can meet various demands for indoor and outdoor atmospheric observation.

A method to measure the quantity of olefin species in a complex hydrocarbon mixture by means of comprehensive multi-dimensional gas chromatography, involves passing a sample of a hydrocarbon mixture through a first capillary column comprising a dimethyl-polysiloxane stationary phase, subjecting the sample to a thermal modulation before entering a second column comprising a 50% phenyl, equivalent, polysilphenylene-siloxane stationary phase, wherein the introduction bandwidth into the second column is smaller than 20 milliseconds.

The invention provides an improved high-efficiency unidirectional heat transfer pipe used for heat dissipation of microelectronics, belonging to the technical field of heat pipes, relating to a strictly unidirectional conductive gravity assisted heat pipe. The heat pipe of the invention is a seal chamber applied to the top of an heat dissipation object and is composed of a condensation section at the upper part, a heat insulation section at the middle part and an evaporation section at the lower part, the interior of the heat pipe is filled with a working medium, and the heat pipe is characterized in that the bottom of the chamber is matched with the shape of the top of the heat dissipation object, and the inner surface is distributed with scratch shallow slots; the top of the chamber is subject to superhydrophobic surface treatment; the inner wall of the chamber is provided with vertically arranged groove channels and capillary column channels separated with rib channels and is subject to superhydrophobic surface treatment; gasification is easier to realize on the surface of the scratch shallow slots at the bottom; the capillary column channels make condensation working medium fluid rapidly reflux, thus avoiding that the working medium of the heat pipe is dried up; and the top of the condensation section is subject to superhydrophobic surface treatment, thus realizing dropwise condensation. Thus, the invention improves condensation heat exchange coefficient and enables the heat pipe to operate normally and stably.

The invention discloses a method for determining menthol in a cigarette filter rod, comprising the flowing steps of: extracting the cigarette filter rod by the use of an extractant to obtain an extraction solution; dissolving menthol by the use of the extractant, followed by a constant volume process, preparing a standard storing solution, and diluting the standard storing solution by the use of the extractant to obtain working standard liquids at a series of concentrations; respectively carrying out chromatography on the working standard liquids and the extraction solution under the same condition by the FID-capillary column gas chromatography method to obtain a chromatogram; calculating the peak area ratio of menthol to an internal standard substance in each working standard liquid, andmaking out the linear regression equation of the menthol concentration and the peak area ratio; calculating the peak area ratio of menthol to the internal standard substance in the extraction solution, and calculating the concentration of menthol in the extraction solution according to the linear regression equation; and calculating the content of menthol in the cigarette filter rod. The method provided by the invention is stable and accurate, is simple to operate, has strong practicality, good repeatability and a wide application range, and can be used for the determination of menthol in filter rods within the industry.

Onium salt chemistry can be used to deposit very uniform thickness stationary phases on the wall of a gas chromatography column. In particular, the stationary phase can be bonded to non-silicon based columns, especially microfabricated metal columns. Non-silicon microfabricated columns may be manufactured and processed at a fraction of the cost of silicon-based columns. In addition, the method can be used to phase-coat conventional capillary columns or silicon-based microfabricated columns.

The invention relates to a rapid determination method for content of a banned azo dye. The method comprises the following steps that a sample solution is prepared and subjected to reduction and extraction; a sample concentrated solution is obtained; for gas chromatography and mass spectrometry conditions, helium serves as carrier gas, and a gradient temperature rise mode is adopted; a DB-35 capillary column serves as a chromatographic column; an EI (electron impact) serves as an ion source, and an ionization mode serves as a normal mode; the flow velocity is 1ml/min, and the split ratio is 15:1; a full scan mode serves as a data acquisition mode; and the sample concentrated solution is injected into a gas chromatography and mass spectrometry instrument, subjected to qualitative analysis according to retention time of a banned azo compound on the chromatographic column and a mass spectrogram, and then subjected to quantitative analysis by an internal standard method according to a peak area of the banned azo compound on the chromatographic column. Compared with the traditional detection technique, the rapid determination method greatly shortens the analysis time of the gas chromatography and mass spectrometry instrument, solves the problem of long testing flow existing in domestic and foreign detection standards at present, and achieves good separation; the selectivity is good; and the recovery rate meets the requirements.

The invention provides an analyzing method for simultaneously determining residues of organophosphorus pesticides and pyrethriods pesticides in soil. The analyzing method is characterized by comprising the following steps: carrying out ultrasonic extraction on a soil test sample by using an acetonitrile solution containing 1% of acetic acid by volume percent; purifying by using a suitable amount of PSA and C18 mixed fillers; blowing liquid supernatant by nitrogen and concentrating until the liquid supernatant is nearly dried; respectively dissolving by acetone and n-hexane and enabling the volume to be constant; raising the temperature by using DB-1701 and HP-5 quartz capillary columns and separating; carrying out GC/FPD (Gas Chromatograph/Flame Photometric Detector) detection and GC/micro ECD (Electron Capture Detector) detection; and finally, quantifying by using a base material external standard method. A test confirms that the method has a wide linear range; the technical indexes including detection sensitivity, accuracy and precision meet the requirements of a residue analysis; the pre-treatment operation is simple, convenient and rapid and a reliable manner is provided for analytical researches for simultaneously determining the residues of ths pesticides and the pyrethriods pesticides in the soil.e organophosphoru.