34 results about "Fused silica capillary" patented technology

A micro counter-current flame detector is provided that is both sensitive for photometric and ionization detection for gas chromatography (GC). In the detector, a stainless steel capillary (0.01″ i.d.) supplying oxygen functions as a burner, which supports a compact flame that burns in a counter-flowing excess of hydrogen. In the “micro Flame Photometric Detector” (μFPD) response mode, the background emission level is reduced by over an order of magnitude compared to previous experiments using a fused silica capillary burner, resulting in greatly improved detection limits. The device can successfully operate as both a selective and universal GC detector. Results indicate that this micro counter-current flame method yields comparable performance to conventional Flame Photometric and Flame Ionization Detectors.

A tip portion of a probe has a triple tube structure in which a fused silica capillary on the innermost side, a capillary made of FEP outside the fused silica capillary, and a stainless pipe on the outermost side are disposed coaxially. An eluate from a liquid chromatograph flows through the innermost flow passage, a matrix solution flows through the flow passage between the fused silica capillary and the FEP capillary, and a rinsing solution or air flows through the flow passage between the FEP capillary and the pipe.

The invention discloses a preparation method of a capillary electrochromatography column filled with fiber, comprising the following steps: one end of the fiber is inserted into the capillary, fluid is conveyed into the connection end of the fiber and the capillary for lubrication, the other end of the capillary is connected with a vacuum pump, vacuum is imposed and the fiber is pumped into the capillary. The adopted lubricate fluid is polar solvents, such as methanol, acetone and water and the like; the filled fiber is silica fiber or glass fiber or fiber with bonding functional groups on the surface, the diameter of the fiber is 5 to 450 Mum and the length thereof is 1cm to 50 cm; the capillary forming the capillary electrochromatography column is a fused silica capillary or polyether ketone capillary or metal capillary or capillary with bonding functional groups on the internal surface and the inner diameter of the capillary is 10 to 500 mum. The method of the invention has simple operation, and the needed material is easy to obtain and can fill the fiber into the capillary electrochromatography column conveniently.

The invention discloses a gas chromatograph and detection method for determining the total content of sulfides in natural gas. The gas chromatograph comprises a quartz capillary column, a hydrogen flame ionization detector, a temperature control unit and a sulfur chemiluminescence reactor which are successively connected, wherein the quartz capillary column is a fused silica capillary column with uncoated inner walls; and the gas chromatograph further comprises a processor which is connected with the sulfur chemiluminescence reactor and a display unit. The gas chromatograph and detection method provided by the invention eliminate influence of hydrocarbons on determination of sulfide content, are more accurate in testing and have a wider application scope.

The invention provides a gas chromatography-mass spectrometry detection method for a methylaniline compound. The method comprises the following steps of: A) extraction of a sample, namely adding an acid into the sample to extract the methylaniline compound into an acid liquor phase, adding alkaline into acid liquor phase extract to regulate pH to be neutral, adding methylene chloride to reextract the methylaniline compound in the neutral extract into the methylene chloride, and performing volume fixing to obtain a sample detection solution; and B) detection of the sample, namely separating the obtained sample detection solution by using a DB-1MS fused silica capillary column, and performing gas chromatography-mass spectrometry detection. The quantitative detection of the methylaniline compound is realized; the method is high in accuracy, low in detection limit, high in extraction efficiency and easy to operate, and can be widely applied to the detection of the methylaniline compound in a crude oil sample, a gasoline sample, a diesel sample and the like; the interference of other compounds in an extraction process can be eliminated; and powerful support can be provided for the environmental performance evaluation and monitoring of the sample.

The invention relates to a method for determining content of gamma-aminobutyric acid through a micellar electrokinetic capillary chromatography method, and belongs to the technical field of chromatographic analysis. The method comprises the following steps of selection and pretreatment of a fused silica capillary column, electrophoretic analysis conditions, gamma-aminobutyric acid standard curve drawing, sample derivatization and quantitative analysis of gamma-aminobutyric acid. Compared with the prior art, the method has the following advantages that micellar electrokinetic capillary chromatography (MECC) is adopted, sodium dodecyl sulfonate (SDS) and beta-cyclodextrin serve as micelle, an organic modified isopropanol reagent is added, gamma-aminobutyric acid is rapidly, easily and efficiently separated from other free amino acids, and gamma-aminobutyric can be detected within 30 min.

The invention discloses a device and a method for preparing a nanotip transfer pipette, and belongs to the fields of nanofabrication. The device comprises a capillary permeability verification device, a capillary drawing system, a capillary etching and a current loop detecting system. The device can be used to prepare a permeable nanotip from a glass capillary or a fused quartz capillary with varied internal and external diameter ratios, and the main breakthrough is that the device is suitable for the capillary with a very small internal and external diameter ratio. The permeable nano transfer pipette tip with the external diameter of the conical tip less than 1 [mu]m is prepared, so that the liquid at picoliter or even femtoliter level can be accurately transferred. The method combines wet etching and current detecting; compared with a traditional preparation method and the conventional other methods, the method has the advantages of simplicity, convenience, high flexibility and high controllability, and moreover, the liquid transferring accuracy is greatly improved; and as the size of the prepared tip is relatively small, the damage to an operation object is greatly reduced.

The invention relates to a high sensitivity detection method of oversulfated chondroitin sulfate in liquaemin. The high sensitivity detection method comprises the following steps of 1) preparing a sample liquid and weighting a liquaemin sample; 2) preparing a standard substance solution and using purification water to dissolve a system suitability standard substance, a liquaemin identification standard substance and an oversulfated chondroitin sulfate standard substance into a solution; 3) preparing a buffered solution and preparing a phosphate buffer or a lithium phosphate buffer in a volumetric flask; and 4) selecting a fused quartz capillary, conducting sample introduction analysis on the liquaemin system suitability standard substance and the liquaemin identification standard substance in the phosphate buffer, and enabling a liquaemin peak of the liquaemin system suitability standard substance and a peak of the oversulfated chondroitin sulfate to be completely separated. The high sensitivity detection method has the advantages of being high in detection sensitivity, short in detection time, simple and convenient to operate, good in reproducibility, capability of effectively controlling the oversulfated chondroitin sulfate in the liquaemin, being favorable for further promoting the quality of liquaemin products and avoiding occurrence of liquaemin contamination accidents again.

A device for protecting electrospray ionization (ESI) emitter tip made on a fused silica capillary nanoscale liquid chromatography (nanoLC) column for robust use of the nanoLC-ESI integrated column.

Germania-based sol-gel organic-inorganic hybrid coatings were prepared for on-line coupling of capillary microextraction with high-performance liquid chromatography. A germania-based sol-gel precursor, tetra-n-butoxygermane and a hydroxy-terminated triblock copolymer, poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide), were chemically anchored to the inner walls of a fused silica capillary (0.25 mm I.D.). Scanning electron microscopy images of the sol-gel germania triblock polymer coating were obtained to estimate the coating thickness. The analyte distribution constants between a sol-gel germania organic-inorganic hybrid coating and the samples (K_cs) were determined. For a variety of analytes from different chemical classes, including polycyclic aromatic hydrocarbons (PAHs), ketones, alcohols, phenols, and amines, the K_cs values ranged from 1.8×10¹ to 2.0×10⁴. The sol-gel germania triblock polymer coatings survived exposure to high temperature solvent conditions (200° C.) with little change in extraction capabilities. Reproducibility of the method for preparation of the sol-gel germania triblock polymer coatings was also evaluated, and the capillary-to-capillary RSD values ranged from 5.3% to 6.5%. The use of higher flow rates in extraction was found to significantly reduce the time required (from 30-40 minutes to 10-15 minutes) to reach equilibrium between the sol-gel germania triblock polymer coating and the analytes in the sample solution.

The invention discloses a thermal desorption-gas chromatograph and detection method for measuring sulfide content in hydrogen. The gas chromatograph comprises an adsorption pipe, a cold trap, a quartzcapillary chromatographic column, a sulfur chemiluminiscence detector, a signal processor and a display device which are connected with one another sequentially. The detection method includes the following steps that: a hydrogen sample is introduced into an adsorption pipe, then the adsorption pipe is heated, and a carrier gas is adopted to blow a sulfide out from the adsorption pipe; the sulfideblown out from the adsorption pipe enters a cold trap in a low-temperature state, the sulfide is absorbed and gathered in the cold trap, the cold trap is rapidly heated, so that the sulfide can be rapidly released from the cold trap in a concentrated manner; the sulfide released from the cold trap enters a sulfur chemiluminiscence detector through a fused quartz capillary chromatographic column with uncoated inner walls; a signal processor receives and processes signals transmitted by the sulfur chemiluminiscence detector so as to obtain a corresponding chromatogram. The thermal desorption-gas chromatograph and detection method are suitable for measuring the content of various sulfides in hydrogen and can be used for impurity analysis in GB/T 37244 ''Fuel Hydrogen for Proton Exchange Membrane Fuel Cell Automobiles''.

A process for detecting the content of main allergen Der f2 for dust mite features that the capillary electrophoresis and electrochemical detection technique with long fused quartz capillary tube andthree-electrode system in dectecting pool is used. Its advantages are high effect and high speed.

Surface-modified silica microparticles that are functionalized with stabilized phospholipid vesicles are described herein. These stabilized vesicles can be functionalized with either transmembrane receptors or membrane associated receptors and used for affinity pull-down assays or other chromatographic separation modalities to provide affinity capture/concentration of low abundance ligands in complex mixtures with minimal sample preparation. Further described are methods and apparatus for forming polymer frits in a fused silica capillary. The capillary containing a monomer solution is placed between one or more heat sources connected to each other via a jig and operatively coupled to a temperature controller. The polymer frits are synthesized via thermal polymerization of the monomer solution using the heat sources, which allows for placement of the polymer frits at a spatially-defined location in the capillary.

The invention belongs to the related technical field of semiconductor surface cleaning, and discloses a device and method for removing nanoscale particles adsorbed on the surface of a silicon wafer. The device comprises a vacuum assembly and a liquid drop emission and acceleration assembly connected to the vacuum assembly; the liquid drop emission and acceleration assembly comprises a liquid storage device, a graphite electrode, a PEEK capillary tube, a fused quartz capillary tube and a grounded extraction electrode; the liquid storage device is arranged above the vacuum assembly and is used for accommodating a conductive solution; the graphite electrode is arranged on the liquid storage device, and two ends of the graphite electrode are connected with a direct-current power supply and theconductive liquid; one end of the PEEK capillary tube is connected with the liquid storage device, the other end of the PEEK capillary tube is connected with the fused quartz capillary tube, and oneend of the fused quartz capillary tube extends into the vacuum assembly; and the extraction electrode is arranged in the vacuum assembly and is opposite to the emission tip formed by the fused quartzcapillary tube. According to the device and method, the cleaning efficiency is improved, the cost is reduced, and no liquid is left after removal.

The invention relates to a preparation method of a fullerene nano-coating gas chromatographic column. The method comprises that (1) fused quartz capillary tubes are activated; (2) amination treatmentis performed; (3) fullerene p-benzoate is prepared, wherein fullerene and azidobenzoic acid are dissolved in methylbenzene under the reaction temperature of 100-220 DEG C for the reaction time of 5-15hours; and (4) fullerene is bonded to a capillary column, wherein an xylene solution containing fullerene p-benzoate with the mass percent of 3%-15% is introduced into the capillary tubes for a reaction for 1-4 hours under the reaction temperature of 150-220 DEG C, the capillary tubes are washed three times with methylbenzene, and then the fullerene nano-coating gas chromatographic column is obtained. According to the method, by adopting fullerene as a stationary phase, the chromatographic column has an electron-lacking polyenoid property and has a high pi-pi interaction with an aromatic compound, thereby having high selectivity; and by the adoption of fullerene and a spherical structure of fullerene, the chromatographic column has excellent spatial selectivity on samples.