30 results about "Chromatographic measurement" patented technology

The invention discloses a method for determining the active substance content in a petroleum sulfonate sample in Daqing Oilfield by liquid chromatography. The mixed solution of sodium dodecylbenzenesulfonate and sodium 2-naphthalenesulfonate is used as a quantitative standard solution; The standard solution is analyzed and detected by liquid chromatography, and the quantitative working curve is drawn; the actual sample solution of petroleum sulfonate with a certain concentration is accurately prepared, and the chromatographic measurement is carried out. The concentration of the active substance in the actual sample of petroleum sulfonate can be obtained by simple conversion at last. The detection performance of the invention is stable, sensitive and rapid, and the analysis speed is fast. The test results have good repeatability and small quantitative error, and the deviation from the test results obtained by the extraction method is about 1%, which can fully satisfy the active substances in the petroleum sulfonate samples used in oilfield chemical flooding. The need for tracking and monitoring of component content and content changes.

The present invention discloses the preparation process of standard theanine contrast product from tea extractive. Tea extractive with theanine content over 10% is prepared into theanine through dissolution in water, ultrasonic extraction, centrifugation to obtain supernatant, water membrane filtering and high efficiency liquid phase chromatographic separation. The quality of the ultimate product is controlled through ultraviolet, infrared and high efficiency liquid phase chromatographic identification. The product has purity reaching 98% (HPLC), and may be used as quantitative and qualitative standard contrast for the high efficiency liquid phase chromatographic measurement of theanine in various tea products.

Described is an apparatus for reducing a temperature variation of a liquid chromatography sample. A tray drive using at least one of linear or rotational motion moves a sample tray along a path inside a sample compartment of the liquid chromatography system. A control module coordinates the movement of the sample tray by the tray drive and the movement of a sample needle by a needle drive so that any sample in the sample tray can be injected into the mobile phase of the system during a sample load operation. The tray drive is also used to move the sample tray along the path during a temperature averaging period when no loading occurs. Differences in sample temperatures due to variations in the air temperature at different locations inside the sample compartment are reduced, leading to more accurate and repeatable chromatographic measurement results.

The invention provides a high-performance liquid chromatography detection method for related substances of 2,4-dimethylthiophenol. The liquid chromatography measurement conditions used are: the chromatographic column is filled with octadecylsilane bonded silica gel, and the mobile phase is phosphate buffer-methanol containing cation pairs. The method has the advantages of simple and convenient method, good specificity, high sensitivity, good repeatability, etc., and is suitable for the qualitative and quantitative detection of related substances in 2,4-dimethylthiophenol.

The invention provides a method for detecting pesticide residues in a traditional Chinese medicine, and particularly relates to a method for detecting 9 organic chloride pesticide residues in anti-inflammatory and analgesic bolus. According to the method provided by the invention, a gas chromatographic method is adopted for measurement through optimization and methodology study on a preparation method of samples to be tested and gas chromatographic measurement conditions. The method has higher precision and repeatability, good sensitivity and a large linear range, can meet the requirements on a sampling recovery test, obtains accurate and reliable measurement results, and can meet the requirements on detection of the organic chloride pesticide residues in the anti-inflammatory and analgesic bolus.

The invention discloses a measuring method for fluorine, chlorine, sulfur and nitrogen in imported petroleum coke. The measuring method includes the steps of connection assembly sample treatment, sample pretreatment, chromatographic measurement, result calculation and the like. The measuring method is convenient, accurate and efficient.

The invention relates to a method for obtaining measurement values ​​of liquid chromatography inspection, comprising the following steps: obtaining a first chromatographic outflow curve; obtaining a baseline from the first chromatographic outflow curve; The peak and valley values ​​of the corresponding chromatographic peak; obtain and retain the first curve between the maximum slope point of the ascending section and the minimum slope point of the descending section of the chromatographic peak corresponding to the required component, and the first curve of the chromatographic peak The first rising curve is translated to obtain the second rising curve; in the same way, the first falling curve and the second falling curve are obtained, and then the first chromatographic peak is obtained; the content value of the required component is calculated according to the first chromatographic peak, and is obtained by the same method The content values ​​of other components in the first chromatographic elution curve are obtained, and then the measured values ​​are obtained from the content values ​​of the required components and the content values ​​of other components. The implementation of the measurement value acquisition method for liquid chromatography inspection of the present invention has the following beneficial effects: the introduced error is small.

The invention discloses a collection method for alkali metals and compounds thereof in air in a working place. The sampling can be finished by introducing the air in the working place into a sulfuric acid and methanesulfonic acid mixed aqueous solution which serves as an absorption medium. The collection method is simple, high in collection efficiency and high in absorption capacity. The invention also discloses a measurement method for the alkali metals and the compounds thereof in the air in the working place. The measurement method comprises the following steps of preparing a standard sequence of alkali metal ions; measuring a standard series, a sample and a blank reference solution through an ion chromatograph, drawing a standard curve, subtracting a response value measured by the sample into the standard curve to obtain the concentration of the alkali metal ions in the sample, and carrying out conversion to obtain the concentration of the alkali metals and the concentration of the compounds of the alkali metals in the air in the working place. According to the collection and measurement methods, various alkali metals and the compounds thereof can be simultaneously collected and measured through one-time sampling and under a chromatographic condition; the chromatographic measurement operation is simple; the stability is high; a result is reliable.

The invention provides an extraction method for galanthamine from lycoris radiate. The method includes following steps: (1) determination of chromatographic conditions: employing a Kromasil100-5C18 reversed-phase column (250mm*4.6mm, 5[mu]m) as an chromatographic column and an acetonitrile-phosphoric acid buffer solution (17:83) mixture as an mobile phase, and setting a column temperature to be 35 DEG C, a sample volume to be 20[mu]L and a detection wavelength to be 290nm, wherein the phosphoric acid buffer solution, which is 7.02 in pH value, is prepared by following steps: dissolving 2.72g of potassium dihydrogen phosphate in 100ml of water, adding 1.4ml of triethylamine and performing a diluting process to 1L; (2) establishment of a standard curve: establishing a regression equation according to the chromatographic conditions in the step (1); and (3) extraction of the galanthamine: weighing 2.0g of lycoris radiate. Herb powder, adding cellulase and pectinase, adding an aqueous solution with a pH value being 4.5 at a certain temperature for carrying out an extraction process for a certain time, performing a 5000r / min centrifuge process for 20 min, taking a supernatant, performing chromatographic measurement and calculating a yield of the galanthamine. The invention is low in extraction cost, is short in extraction time, is simple in technology, is free from polluting environment and is high in extraction yield.

The invention relates to a pulse flame four-dimensional measurement method based on deflectometric chromatography. The method provided by the invention can be used to form a 4D-CT multi-visual angle projection ordered array deflection imaging system, and an optimal sampling angle can be determined according to structural characteristics of a detected flow field, and after beam expanding and collimation of a laser beam emitted by a laser source and spatial filtering, a beam splitter can be used for secondary beam splitting to generate a plurality of projection beams, and then a Moire deflection strip array can be generated. Based on the strip pattern processing technology of the wavefront reconstruction, the light deflection information of the projection strips can be extracted. The compressive sensing reconstruction algorithm based on the deflection angle correction reconstruction can be used for the back calculation, and the two-dimensional parameter distribution of different strip pattern cross sections can be acquired. By adopting the single threshold segmentation method for the threshold segmentation of the reconstructed two-dimensional temperature distribution, and adopting the Visualization Tool Kit technology based on the Marching Cubes surface drawing algorithm and the Ray Casting volume drawing algorithm, the three-dimensional volume data dynamic display of the pulse combustion flow field and the flame structure can be realized.

Methods and apparatus for operating fluid-insulated electrical equipment (1) are disclosed. An insulating fluid (10) of an electrical device (1) comprises at least two fluid components (A, B), which are a priori components of the insulating fluid (10). The method comprises the step of performing at least one optical measurement and / or at least one gas chromatographic measurement of the insulating fluid (10). Using this or these measurements or at least one additional measurement of the insulating fluid (10), a first concentration (cA) of the first fluid component (A) and a second concentration (cB) of the second fluid component (B) are derived . The operating state (O) of the electrical device (1) is then derived using the first concentration (cA) and the second concentration (cB) and advantageously the dielectric breakdown strength Ebd of the insulating fluid (10).