31 results about "Chemical standard" patented technology

A method for the in-instrument recombination of volatiles using a gas chromatograph with mass spectrometry and olfactometry detection is described. Compounds that are introduced into the modified GC are separated conventionally on an analytical capillary GC column. The elution profile of volatiles can be segmented, analyzed and arbitrarily combined. In-line with the GC column, a pneumatic flow switch and splitter are connected to a detector and olfactometer. A cold trap allows the user to build a mixture of separated volatiles that is held until the cryotrap is rapidly heated, releasing the mixture for a subject to smell at the olfactory port and to evaluate. The instrument allows for characterization of the aroma quality of specific fractions of aroma volatiles obtained from foods, flowers or beverages without the need for pure chemical standards or the calculation of individual compound concentrations or sensory thresholds.

The invention discloses a preparation method for a 2D70 aluminium alloy spectrum and chemical standard sample, which relates to a developing method of an aluminium alloy standard sample and solves the problem in the prior art that 2-series aluminium alloy standard samples are insufficient. The method comprises the steps of designing components; smelting and casting a circular alloy cast ingot; carrying out homogenizing heat treatment, initial examining for homogeneity and macro examination; carrying out extrusion molding and homogeneity examining; and carrying out valuing and data processing, and then obtaining the 2D70 aluminium alloy spectrum and chemical standard sample. The standard sample developed by the method meets requirements in GB / T15000 Standard Sample Work Guideline and YS / T409 Standard Sample Technical Regulation for Non-Ferrous Metal Product Analysis. The method is suitable for 2D70 aluminium alloy spectrum and chemical analysis.

The invention discloses a preparation process for separating and purifying strychnine from total alkali of nux vomica. Pure strychnine with the content exceeding 94% is prepared by taking total alkali of nux vomica as the raw material through a column chromatography and organic solvent extraction purification and separation method. The pure strychnine can be used as a chemical standard substance and a reference substance of nux vomica or an extract of the nux vomica or used as a raw material of a preparation. The preparation process is not only low in cost, simple and easy in process, but also applicable to the preparation of a larger amount of pure strychnine, and has wide social and economic effects.

The invention discloses a preparation method of an industrial molybdenum oxide chemical standard sample. The method comprises the following steps: 1, selecting industrial molybdenum oxide and carryingout grinding, crushing and screening to obtain screen underflow powders; 2, uniformly mixing the screen underflow powders to obtain industrial molybdenum oxide powders; 3, sampling the industrial molybdenum oxide powders and carrying out preliminary uniformity inspection, carrying out subpackaging after the inspection result is qualified, then, carrying out sampling, sequentially performing uniformity inspection and collaborative valuing, performing mathematical statistics according to a collaborative valuing result, taking the industrial molybdenum oxide powders with qualified results as theindustrial molybdenum oxide chemical standard sample, and calculating uncertainty of characteristic values of the industrial molybdenum oxide powders. The industrial molybdenum oxide chemical standard sample prepared by the method is similar to or even the same with molybdenum oxide in production in composition and content; the method for determining the characteristic value elements or components is accurate; and the method solves the problem of lack of industrial molybdenum oxide chemical standard samples for determining the contents of main molybdenum and impurity elements of industrial molybdenum oxide in the prior art, and is wide in application range.

A method for preparing standard sample includes forming standard sample composition by wt % of 0.05 -1.0% Si, 0.1 -1.5 % Fe, 0.01 -0.5 % Cu, 0.05 -1.5 % Mn, 1.0 -10.0 %Mg, 0.01 -0.5 % Zn, 0.01 -0.5 Ti, 0.01 -0.5 % Cr, 0.01 -0.3 % Ni, 0.0001 -0.01 % Be and Al as allowance ; mixing and melting above material except Mg and Al ; adding mg and Al in and agitating the material for refining ; casting the material in crystallizer after 30 min resting ; carry out homogenizing treatment ; using lathe to move off 8 - 10 mm skin of cast ingot and using the boring mill to cut off phi 22 - 25 mm centre to obtain cylinder spectrum standard sample of aluminium alloy.

The invention discloses a preparation method for quickly separating plant proanthocyanidin dimer and trimer. The method comprises the following steps: performing liquid-liquid extraction on an alcohol solution rich in plant proanthocyanidin raw material, and then flowing by a gel column, performing FPLC (Fast Protein Liquid Chromatography) or HSCCC (High Speed Counter Current Chromatography) separation, thereby separating and acquiring the proanthocyanidin dimer and trimer components. The technology disclosed by the invention is suitable for the separation and purification of the proanthocyanidin dimer and trimer from different resources and has universality. The proanthocyanidin dimer and trimer acquired according to the preparation method disclosed by the invention are higher in purity. The method has the advantages of high safety, simple operation, less time consumption, low production cost, environmental protection, reaching green chemical standard, suitability for industrial production and ultrahigh commercial value.

The invention provides a dry chemical standard reagent piece which comprises a supporting layer, a dye layer, a reflective layer and an auxiliary layer which are sequentially arranged from bottom to top; the supporting layer is a transparent base film layer, the dye layer is of a layered structure formed by coating a dye solution on the supporting layer, and the reflective layer is a white polymeric film layer. The invention also provides a method for preparing the standard reagent sheet. According to the dry chemical standard reagent piece and the preparation method thereof, the prepared standard reagent piece is stable in performance, low in measurement variable coefficient and accurate in measurement result, can be completely matched with a dry chemical analyzer, and is suitable for calibration of the dry chemical analyzer.

The invention discloses a preparation method for quickly separating plant proanthocyanidin dimer and trimer. The method comprises the following steps: performing liquid-liquid extraction on an alcohol solution rich in plant proanthocyanidin raw material, and then flowing by a gel column, performing FPLC (Fast Protein Liquid Chromatography) or HSCCC (High Speed Counter Current Chromatography) separation, thereby separating and acquiring the proanthocyanidin dimer and trimer components. The technology disclosed by the invention is suitable for the separation and purification of the proanthocyanidin dimer and trimer from different resources and has universality. The proanthocyanidin dimer and trimer acquired according to the preparation method disclosed by the invention are higher in purity. The method has the advantages of high safety, simple operation, less time consumption, low production cost, environmental protection, reaching green chemical standard, suitability for industrial production and ultrahigh commercial value.

The invention discloses a preparation method of an adsorption separation material used for removing harmful metal ions in apple juice. The adsorption material commonly used at present is adsorption resin, and its adsorption purpose is mainly to decolorize, and harmful metal ions cannot be removed. The material prepared by the present invention is a kind of fiber adsorption material, and its main operation steps are as follows: select polypropylene non-woven fabric to wash and dry dry, and then put it into the monomer solution to soak it, and co-irradiate electron beams in the air for grafting, and alternately wash it with hydrochloric acid and sodium hydroxide dilute solution to wash off the monomer and the homopolymer of the monomer. The invention has good adsorption and separation performance for harmful metal ions in apple juice. After adsorption and separation, Cu2+≤5ppm, Pb2+≤0.2ppm, and As3+≤0.1ppm in apple juice can fully meet the quality standard requirements of concentrated apple juice and can effectively remove apples. Harmful metal ions in the juice can be eliminated, the quality of apple juice can be improved, and it can meet food hygiene safety and physical and chemical standards.

The invention discloses application of three coumarins compounds namely daph-neticin, daphnetin and 7-hydroxy-8-methoxycoumarin in preparation of a hepatitis c virus protease NS3 / 4 A inhibitor and hepatitis c treating medicines, and a method for extracting, separating and purifying the coumarins compounds from winter daphne (Daphnepapyracea Wall.ex Steud.var. crassiuscula Rehd.). The three coumarins materials have strong inhibition effect on hepatitis c virus protease NS3 / 4 A, are high in activity and can be used for preparing the medicines for preventing and treating hepatitis c independently; or the coumarins materials can be compounded with other components for preventing and treating hepatitis c; besides, the inventor extracts and separates the three coumarins compounds from the winter daphne plant for the first time by the modern plant chemical separation and purification technology; and the purity of the compounds is 98%; and the compounds can be applied as chemical standard substances for medicine test.

A casting system for casting a chemical standard sample blank comprises a base case (1) with an openmouthed top, a plurality of molding dies (2) positioned in the base case (1), a flow collector (3) positioned at the openmouthed end of the base case (1) through a positioning structure, and a flow retardation device (4) placed on the flow collector (3) and with one end spaced horizontally and supported on the support body of the base case (1), the bottom of the flow collector (3) is provided with liquid outlets (3.1) for the respective injection of melt in the flow collector (3) into the molding dies (2), the liquid outlets (3.1) are arranged corresponding to casting holes (2.1) of the molding die in a one-to-one manner, and the bottom of the slow retardation device (4) is provided with a liquid outlet structure enabling the melt in the slow retardation device (4) to be filtered to form a slow flow entering the flow collector (3). The casting system has the advantages of effective shortening of the casting time, reduction of the secondary oxidation probability, improvement of the purity of the melt, and obtaining of high quality products.

The present invention provides an automatic two-dimensional high-performance liquid phase preparative chromatography device, which can be used for automatic purification of laboratory-scale (<1 g) chemical standards. The device includes a large-flow constant-flow pump, a liquid multi-position valve, a high-efficiency preparative chromatographic column, an ultraviolet detector, and a self-made two-dimensional liquid chromatography interface. After the target substance is separated by the first-dimension chromatography, the solvent is removed in the self-made two-dimensional liquid chromatography interface device (9), and the second-dimension separation is carried out after dissolving with the mobile phase of the second-dimension chromatography. The device can realize automatic solvent selection; automatic flow path and chromatographic column selection; automatic collection of target components. The purified target compound solution will be collected at the designated receiving location, and a high-purity standard can be obtained after simple rotary evaporation. The advantages of this device are: 1. Low cost, compact structure and light weight; 2. Simple to use and high degree of automation; 3. There are three different purification operation modes: one-dimensional normal phase, one-dimensional reverse phase, and two-dimensional separation, with a wide range of applications , the solvent cost is low, and the purification effect is good.

The invention discloses technology for purifying hypericin. The technology is to take hypericum perforatum, overground parts provided with flowers of other plants containing the hypericin, and a crude extract or flower of the plants as raw materials, and to prepare hypericin purified products of which the content is higher than 98 percent after solvent extraction, separation and purification. Thepurified products can be used as chemical standard substances, reference substances or raw materials of preparation.

The invention discloses a method for preserving and transporting immune cells and belongs to the technical field of biology. The method comprises the following steps of collecting peripheral blood or umbilical cord blood, and conducting dilution, so that cell suspension is obtained; adding a separating medium containing trehalose, ultra-low-viscosity sodium alginate and amino acid into a centrifuge tube, laying the cell suspension flat on the separating medium, conducting centrifugation, absorbing upper layer blood plasma for use, and absorbing albuginea layer cells, so that lymphocyte is obtained; mixing the lymphocyte with a cryopreservation solution in the same proportion, and placing the mixture into a cell cryopreservation tube; conducting cryopreservation; after the lymphocyte thaws, moving the liquid cell suspension into a centrifuge tube containing normal saline with the temperature ranging from 4 DEG C to 8 DEG C, mixing the mixture uniformly, and conducting centrifugation; adding preserving fluid containing trehalose with the concentration being 2% to the lymphocyte; moving the mixture into a sterile tube or a transfer bag for transfer. According to the method, raw materials meeting the intravenous injection level bulk pharmaceutical chemical standards are selected for all stages from separation to cryopreservation and then to preservation and transportation, uncertainty of the raw materials is low, and safety is high.

The invention discloses a chemical standard experiment table for students. The experiment table comprises a framework (1), a table top (2), a side plate (3), an instruction case (4), a water feeding and discharging part (5) and a power supply unit (6), wherein the main body framework (1) of the experiment table is of a plastic steel structure, and the table top (2), the side plate (3) and the panel of the instruction case (4) are made of an imported solid-core physicochemical plate material and thermally fixed on the main body framework (1) via the king of hot glues imported from Germany by using a thermoforming machine, thereby forming the integral experiment table. The water feeding and discharging part (5) employs a high-quality test water tank, a copper chrome-plated triple water nozzle and a ceramic chip water valve. The power supply unit (6) is provided with a short circuit overload protection device which enables AC-DC voltage to be controlled in a range of 2 to 24 V and a maximum current to be 2A. The experiment table provided by the invention has the advantages of a firm and reliable integral body, a beautiful shape, acid and alkali resistance, high temperature resistance, water resistance, fire resistance, no leakage and obstruction at the water feeding and discharging part, integral insulation and no electric leakage and can be used as modern teaching equipment for chemical laboratories in middle schools.