68results about How to "The assay method is fast" patented technology

The invention provides an edible oil quality inspection method based on 1H-nuclear magnetic resonance (NMR) fingerprint spectra and multivariate analysis. The edible oil quality inspection method is mainly characterized by comprising steps of developing 12 1H-NMR fingerprint spectra for identifying swill-cooked dirty oil; establishing an oil 1H-NMR fingerprint spectrum database according to the 12 1H-NMR fingerprint spectra; classifying samples in the database by clustering analysis; establishing a discriminant function, substituting 1H-NMR data of an unknown sample into the discriminant function; and judging the quality of the unknown sample according to a calculated result. The edible oil quality inspection method has the advantages of small sample quantity, simple pretreatment method, high sensitivity, low cost and high accuracy.

The invention discloses a method for detecting a heavy metal content of coal gangue filling reclamation reconstruction soil based on a high spectrum technology. The method comprises the steps of performing sampling on site; collecting a sample spectrum curve; performing data processing; constructing a high spectrum estimation model for inverting soil heavy metal content; constructing a partial least squares regression model; and finally utilizing the partial least squares regression model to detect the heavy metal content of the coal gangue filling reclamation reconstruction soil. Compared with a conventional multiple linear regression analysis method, according to the method, the problem of multicollinearity faced by the multiple linear regression analysis method is solved, spectral information can be summarized and extracted, system information and noise are identified more easily, and thus the content of heavy metal elements can be quantitatively inverted accurately. The simple and quick detection method is provided for large-area low-cost investigation and monitoring of heavy metal pollution of mine lot reclamation land soil, technical means are provided for guaranteeing mine lot reclamation land crop safety, and development and application of a high spectrum remote sensing technology are promoted.

The invention relates to a cement clinker component determination method in cement production, in particular to a method for determining calcium sulfoaluminate content in cement clinker, which comprises the following steps of: connecting experimental instruments such as a tubular type high-temperature furnace, a nitrogen cylinder, a tower type drier, an absorption bottle and a glass rotor flowmeter, and measuring the content of C4A3S in cement clinker according to experimental steps. The method provided by the invention has the advantages of rapid, accurate and reliable determination, simple instrument and equipment, low cost and convenient operation, and is suitable for C4A3S content determination of cement clinker in factory production, thus facilitating timely production control.

The invention discloses a method for determining thermal-conduction resistance of a metal foam porous medium. The method comprises the following steps: placing a to-be-determined metal foam porous medium between a hot plate and a cold plate and carrying out vacuumization; energizing and heating the hot plate at an upper part and cooling the cold plate at a lower part via a cooling module; when the whole heat transfer process reaches a stable state and a certain degree of vacuum is reached and maintained unchanged in a test section, acquiring data like temperature, current and voltage in real time by using a data acquisition and processing system; and processing the acquired data by using the data acquisition and processing system so as to eventually obtain thermal-conduction resistance of the metal foam porous medium and providing a test report. The determination method provided by the invention is rapid and simple and has high accuracy.

The invention discloses a device for sampling asphalt smoke dust, which consists of a closed container, a heating furnace, a temperature controller, a freezer, an absorption device, a water container and a dry air supplying device, wherein an air outlet of the dry air supplying device is connected with an air inlet of the closed container; an air outlet of the closed container is connected with an air inlet of the absorption device; an air outlet of the absorption device is positioned under the liquid level of the water container; the heating furnace is connected with the temperature controller; a temperature sensing part of the temperature controller is connected with the closed container; the heating furnace is used for heating the closed container; asphalt with unit mass is arranged inthe closed container; the absorption device is arranged in the freezer; adsorption substance is arranged in the absorption device; and the freezer is internally provided with cooling substance. The invention also discloses a method for measuring the content of the asphalt smoke dust. The invention has the beneficial technical effects that the sampling device is simple in structure and convenient to operate, the measurement method is simplified and rapid, and the measurement result is high in accuracy.

The invention provides a method of measuring residual liquid hydrocarbon content in shale via low-field nuclear magnetic resonance. A shale sample of any shape is used to saturate manganese chloride solution of sufficient concentration; low-field nuclear magnetic resonance is then performed to obtain a nuclear magnetic T2 spectrum in the shale sample; the shale sample is subjected to dewatering prior to dealkylation; a T2 spectrum signal is measured again; amplitude integral difference delta S of the T2 spectral signal is introduced into a calibration relationship (namely, a marking equation)of hydrocarbon content and the signal, built in the method, so as to calculate hydrocarbon volume in shale of unit volume; the result is that the hydrocarbon volume in shale of unit volume is presented by percentage, which is considered as residual liquid hydrocarbon content in shale. The problems are effectively avoided that samples experience light hydrocarbon loss due to crushing pretreatment and that insufficiency of solvent polarity leads to incomplete extraction of heavy hydrocarbons; the method is suitable for precisely measuring residual hydrocarbon content in shale and is an effectiveand quick measuring method.

The invention discloses a method for detecting the content of methylene blue in blood plasma. The method comprises the following steps of: (a) adding carboxymethyl-beta-cyclodextrin saturated solution into blank blood plasma, enabling the concentration of the mixed solution to reach 1-4.5mmol/L and maintaining the constant volume to obtain a blood plasma blank sample; (b) adding quantitative methylene blue solution into the blank blood plasma and adding the carboxymethyl-beta-cyclodextrin saturated solution to obtain a standard blood plasma sample containing the methylene blue with the concentration of Cs; and (c) adding the carboxymethyl-beta-cyclodextrin saturated solution in a blood plasma sample containing the methylene blue to obtain a blood plasma to-be-measured sample containing the methylene blue with the concentration of Cs; detecting the strength or the area of a fluorescence peak of the sample; and then calculating according to a reference substance comparison method to obtain the concentration Cs of the methylene blue in the blood plasma to-be-measured sample. According to the method disclosed by the invention, the lowest detectable limit is 0.012mumol/L and the unexpected effect is obtained.

The invention discloses a method using a single point adsorption method to measure the specific surface area of atmospheric particulates. The single point adsorption method utilizes a methylene blue water solution and comprises the following steps: (1) collecting atmospheric particulates, cutting, and weighing; (2) preparing a diluted original solution of methylene blue and a standard solution, determining the absorbance of standard solution, and drawing a work curve; (3) determining the absorbance of methylene blue solution, and calculating the adsorption amount of methylene blue according to the work curve; (4) calculating the specific surface area of atmospheric particulates. The method is simple, feasible, fast, and convenient, is suitable for measuring the surface area of atmospheric particulates, and has the characteristics of simple technology, low cost, strong operability, and low instrument requirements.

The invention discloses a method for measuring bacitracin and the content of the preparation thereof by the turbidity method, and the method contains the following steps: the preparation of standard solution, the preparation of test solution, the preparation of test organism suspension, the content measurement, etc. The antibiotics-microbial test and multi-dose turbidity method of the invention are adopted for measuring the bacitracin and the content of the preparation thereof, thus the test method is accurate and effective and has low cost, and test results can truly reflect antibacterial activity of the bacitracin and the preparation thereof; the method has stronger practicality and operability in the production and the quality control of the drug and the preparation thereof.

The invention relates to a method for detecting musk xylene in a tobacco additive and belongs to the technical field of detection of tobacco additives. The method comprises the following steps of: weighing 1.0g of tobacco additive and putting into a 50mL conical flask with a plug, adding 10mL of ultrapure water of which electrical resistivity is 18.2 M Omega and dispersing a sample, adding 0.3mL of D15-musk xylene interior label solution with the concentration of 1mu g/mL, and 10mL of cyclohexane, oscillating and extracting at the temperature of 25 DEG C for 10 minutes, centrifuging a mixed solution at rotation speed of 4,000r/min by a centrifugal machine for 10 minutes, extracting an upper-layer organic phase, adding 10mL of chromatographically pure cyclohexane into a water phase of which the upper-layer organic phase is extracted, performing secondary extraction under the same operation conditions, centrifuging, and extracting an upper-layer organic phase; and mixing the organic phases extracted twice, drying by using anhydrous sodium sulfate, and metering the volume to ensure that the volume is 1mL for gas chromatography-mass spectrometer (GC-MC) determination. The method has the advantages of high sensitivity and capacity of effectively determining the content of musk xylene in the tobacco additive, and can determine the content of the musk xylene accurately and quickly, and is suitable for monitoring and self-inspection work of the highly-concerned musk xylene in the tobacco additive.

The invention relates to a method for measuring perfluorinated compounds in textile, clad layers, coatings, liquid and powder samples. The method comprises the measuring steps that firstly, a sample is cut according to a certain dimension in an area method or a sample of a proper amount is weighed in a weight method, an organic solvent is added for ultrasonic extraction, and the mixture is cooled to the room temperature and then filtered to be fed into a machine for analysis; secondly, the quantity of perfluorinated compounds in the extracted solution obtained in the first step is measured through a liquid chromatogram and mass spectrum combined instrument; thirdly, if a liquid chromatogram and mass spectrum selected ion scanning result shows that perfluorinated compounds seem to be contained in the sample, a spectrogram of the sample is compared with that of a standard substance, if the spectrogram of the sample is matched with that of the standard substance, the extracted solution obtained in the first step is measured through a liquid chromatogram tandem mass spectrum combined instrument, characteristic ions of the sample are compared with those of the standard substance to confirm whether perfluorinated compounds are contained in the sample or not, and the content of perfluorinated compounds in the sample is calculated. The measuring method is fast and simple, and perfluorinated compounds in various materials can be accurately measured.

The invention discloses a determination method for the chromium content in cotton-seed meal. The determination method includes the steps that different kinds of cotton-seed meal samples planted in different regions are prepared, a near-infrared spectrometer is used for collecting spectrums of the cotton-seed meal samples, full cross validation is adopted in a full spectrum range to build a PLS model, and then the PLS model is analyzed by adopting eight preprocessing methods; a processing method corresponding to the maximum prediction correlation coefficient R2 and the minimum root-mean-square error RMSE is used as the optimal preprocessing method, and a near-infrared spectrum correction model is set up through the optimal preprocessing method; the near-infrared spectrum correction model built in the step mentioned above is used for detecting the cotton-seed meal to be detected to obtain the chromium content of the cotton-seed meal. The FOSS5000 near-infrared spectrometer is used for collecting spectrograms of the cotton-seed meal, determination accuracy is high, and the determination method is fast, convenient and efficient and has great significance in cultivating new cotton species and promoting processing and utilization of cotton by-products.

The invention relates to a method for detecting tanshinone components, and an application thereof. The tanshinone components are dihydrotanshinone, cryptotanshinone, tanshinone I and tanshinone IIA. The method comprises the following steps: collecting samples to be tested in the extraction and concentration of Salvia miltiorrhiza, collecting the near infrared spectra of the samples to be tested bynear-infrared spectroscopy, and converting the near infrared spectra into the respective content of dihydrotanshinone, cryptotanshinone, tanshinone I and tanshinone IIA in every sample to be tested according to a selected model. The method has the advantages of fastness in detection of the respective content of the tanshinone components in a compound Salvia miltiorrhiza tablet, simplicity in thepreparation of the samples, and realization of online analysis.

The invention relates to a method for detecting the content of guanidine phosphate in textile and a filling material. The method comprises the following steps: 1, preprocessing a sample: shearing a textile or filling material sample by scissors or crushing the sample by a crusher in order to form a sample with the dimension size not exceeding 2*2*2 mm, uniformly mixing the sample, filling a clean and dry valve bag with the sample, and sealing the valve bag for later use; 2, extracting the sample: weighing a proper amount of the sample, and carrying out ultrasonic extraction by using a methanol-water solution; 3, detecting the concentration of guanidine phosphate in a sample extract solution obtained in step 2 through adopting liquid chromatography-mass spectrometry; and 4, calculating the content of the guanidine phosphate in the sample according to the concentration of the guanidine phosphate in the sample extract solution, obtained in step 3. The detection method is fast and simple, and can realize accurate detection of the guanidine phosphate in textile and the filling material, the lowest quantification concentration is 5 mg/kg, and a problem that no methods for detecting the content of a fire retardant guanidine phosphate exist is solved.

The invention relates to a method for measuring bisphenol-S in consumer goods. The measuring method includes the steps that (1) a smashed and evenly mixed sample is taken, an organic solvent is added to the sample, extraction is conducted, an extracted solution is concentrated through a rotary evaporation instrument, and dilution constant volume is conducted on the solution through methanol and water; (2) for a plastic product sample and a wooden product sample, the extracted solution generated after concentration and methanol-water constant volume are conducted is purified through a small HLB pillar; (3) the amount of bisphenol-S in the methanol-water solution obtained through the step (1) or the step (2) is measured through a liquid chromatograph-mass spectrometer; (4) Comparison between the sample and a full scan mass spectrogram of standard matter on the aspects of the retention time, the characteristic ions and the abundance ratio is conducted is conducted, whether the sample contains the bisphenol-S or not is determined, and finally the content of the bisphenol-S in the sample is calculated after conversion according to the amount of the bisphenol-S obtained in the step (3). The measuring method is rapid and simple, the content of the bisphenol-S in the consumer goods made of various materials can be accurately measured, and the detection limits each can reach 0.1 mg/kg.

The invention belongs to the technical field of analysis chemistry and particularly relates to a method for measuring calcium stearate in a drug. The method comprises the following steps of: 1) extracting a sample solution, adding hydrochloric acid to the sample solution to acidize the sample solution, extracting through normal hexane to obtain a normal hexane extracting solution, rotationally evaporating and concentrating the normal hexane extracting solution, and blowing to dryness by using nitrogen; 2) carrying out methyl esterifying, namely, adding methanol into the solution to dissolve, adding sulfuric acid, uniformly mixing, and extracting a methyl esterified product through normal hexane, helically and uniformly mixing, stewing for layering and extracting the normal hexane layer; 3) measuring the dosage of the methyl stearate in the normal hexane layer obtained in step 2) through a gas chromatograph-mass spectrometer; and 4) finally calculating the content of calcium stearate in the sample solution according to the dosage of the methyl stearate obtained in step 3). The method disclosed by the invention is used for measuring calcium stearate in the drug through the gas chromatograph-mass spectrometer by acidizing the sample to extract stearic acid; and the measuring method is not only quick and simple, but also capable of being used for accurately measuring the content of calcium stearate in the drug, and the detection limit is low.

The invention discloses a method for determination of padimate in cosmetics, wherein the method includes the following steps: (1) pretreating samples; (2) analyzing padimate by high performance liquid chromatography, and optimizing high performance liquid chromatography conditions; and (3) drawing a standard working curve, quantifying by adopting an external standard method, and calculating the content of padimate. The method for determination of padimate in the cosmetics adopts the high performance liquid chromatography for simultaneous determination of padimate A and padimate O in the cosmetics; the samples detected to be positive by the high performance liquid chromatography are further identified by using high performance liquid chromatography-mass spectrometry/mass spectrometry. The method is accurate and fast, is high in sensitivity, and has a great significance for monitoring of the cosmetics quality safety risks.

The invention provides a method for rapidly determining the content of a flame retardant in inorganic flame-retardant cellulose fibers. The content of the flame retardant in the inorganic flame-retardant cellulose fibers is rapidly determined by adopting a low-field pulse nuclear magnetic resonance method. The rapid determination method established on the basis of the low-field pulse nuclear magnetic resonance technology has the advantages of simplicity in operation, short test time, high precision, good stability and accurate and reliable measurement result, the quantity of samples required by the test is small, the morphological structure of the samples cannot be damaged in the test process, the samples can be recycled, and resources are saved; the determination method disclosed by the invention is rapid, accurate and good in reproducibility, can be used for simultaneously determining the moisture content and the flame retardant content of an unknown flame-retardant fiber sample at one time, has good conformity between detection data and data obtained by a conventional laboratory determination method, can meet the requirement of rapid analysis and detection of the flame retardant content of a flame-retardant cellulose fiber product, and has good practicability.

The invention discloses a determination method which determines the reduction degree of a cadmium-copper reduction post in water nitrate by continuous flowing automatic chemistry analysis instrument; the basic technical route is that: firstly, nitrite analysis module of multi-channel continuous flowing automatic chemistry analysis instrument is used to analyze nitrite standard series; secondly, nitrate analysis module is used to analyze nitrate standard series; thirdly, nitrate analysis module is used to analyze nitrite standard series; finally, the reduction degree of the cadmium-copper reduction post is determined by slope combination.

The invention discloses a method for rapid determination of feruloyltyramine content in Pothos chinensis, and the method is based on high performance liquid chromatography technology for determination of feruloyltyramine content in Pothos chinensis. The rapid determination is simple and accurate, has high sensitivity, good precision, good stability, and is very conducive to application in rapid quality control of Pothos chinensis medicinal material in the pharmaceutical process.