88results about How to "Optimize detection conditions" patented technology

The invention relates to a method of characterizing interaction between two species in a liquid environment, wherein a liquid comprising said at least one species is passed as a flow through a measurement system, and wherein the interaction takes place within said measurement system. The method comprises generating a concentration gradient of at least a first one of said species or of at least one other species having an influence on the interaction or on interacted components. The flow of liquid is passed through a sensor device, and a result of interaction between said at least two species is detected. The flow of liquid is intersected at least once with a further liquid before the flow is passed through said sensor, so as to create at least two separated liquid segments having different concentrations of at least one of said species forming the concentration gradient.

The invention discloses a portable muscle mechanical parameter and muscular strength in vivo ultrasonic detection device and method. The device consists of a broadband ultrasonic probe, a multi-channel ultrasonic system and a man-machine interactive system, wherein the multi-channel ultrasonic system communicates with the man-machine interactive system through a local area network or a USB (universal serial bus) 3.0 interface. The device performs ultrasonic signal acquisition on the muscle of a human body or an animal in vivo, performs intelligent analysis and processing on a detection signal in time, extracts a plurality of characteristic parameters related to the muscle strength to perform imaging respectively, supports tracking and tracing measurement under a multi-image model, combines the traditional B scanning image to realize measurement and quantitative display of the mechanical property parameters and the muscle strength of single muscle, and predicts the health state of the muscle according to a muscle preset threshold value and gives alarm prompt correspondingly. According to the device and the method, in vivo, non-invasive, real-time, precise and overall quantitative evaluation on the muscle mechanical properties and the muscle strength is realized.

The invention belongs to the technical field of physiochemical detection of tea leaves and in particular relates to a method for determining alkaloids in tea leaves by using a GC-MS (Gas Chromatography-Mass Spectrometer) method. The method comprises the following step of determining nicotine and minor alkaloids (including nicotine, nornicotine, myosmine, neonicotine, neonicotine and cotinine) in tea leaf powder. The method is a method for extracting nicotine substances from the tea leaves by using a centrifugal tube filled with 0.01% triethylamine/tert-butyl methyl ether solution and analyzing the nicotine substances in the tea leaves by using a gas chromatography-mass spectrometer (GC-MS) method. When the method provided by the invention is used for detecting the content of the nicotine in the tea leaves, the method is rapid and effective, the pre-treatment is simple, an average relative standard deviation is smaller than 10 percent, and the average recycling rate of each index is 86.2 percent to 92.1 percent. The method has the advantages of rapidness and accuracy, high sensitivity and good repeatability.

The invention relates to a method for simultaneously detecting 15 antibiotics in aquaculture sediment by combining microwave extraction-solid phase extraction pretreatment with a liquid chromatography-mass spectrometry (LC-MS) technology. The method comprises the following steps: step (1) pretreating sediment samples, adding internal standard substances sulfamethoxazole-13C6, norfloxacin-D5, penicillin G potassium salt-D5, tetracycline-D6, olaquindox-D4, amoxicillin-13C6 and trimethoprim-D3 indicating a recovery rate, adding an acetonitrile-phosphate buffer solution for microwave extraction ofextraction liquid; step (2) performing solid phase extraction, enrichment and purification on target antibiotics; and step (3) quantitatively detecting 15 antibiotics of seven types in sediment witha liquid chromatograph/mass spectrometer. The method can simultaneously detect residues of 15 antibiotics containing 8 new antibiotics in the aquaculture sediment at a time by optimizing the internalstandard substances, screening appropriate pretreatment method and optimizing detection conditions, and has the advantages of high recovery rate, high sensitivity, high stability, low detection limit,more true and reliable detection results and the like.

The invention discloses a method for detecting chromium, nickel, arsenic, selenium, cadmium and lead elements in cigarette ashes. The method is characterized in that cigarette ashes are collected by using a cigarette ash plate, a cigarette ash sample is dispelled by adopting a microwave digestion method, and the contents of chromium, nickel, arsenic, selenium, cadmium and lead elements in the cigarette ashes are detected by inductively coupled plasma mass spectrometry. The cigarette ashes are collected by adopting the cigarette ash plate, independent collection of each cigarette ash is achieved on a conventional smoking machine, and loss of cigarette ashes and cross contamination of different cigarette ashes in the smoking process are effectively avoided. The sample is processed by adopting the microwave digestion method, so that the risk caused by use of a perchloric acid in the traditional electric hot plate digestion mode is avoided, the dosage of the acid is reduced, the digestion ability is improved, the method is good in digestion effect, less in element loss, and simple and easy to operate, and the used mixed acid system is applicable to treatment of the cigarette ash sample, and thorough to digest. The interference is effectively corrected by adopting inductively coupled plasma mass spectrum parameters, and the method is high in sensitivity, good in repeatability, high in recovery rate, and accurate in result.

The invention provides a method for simultaneously detecting 15 antibiotics in an aquaculture water body by solid-phase extraction pretreatment combined with a liquid chromatography-mass spectrometrytechnology. The method comprises the following steps: (1) water sample pretreatment: adding seven internal standard substances for indicating the recovery rate, namely sulfamethoxazole-13C6, norfloxacin-D5, penicillin G potassium salt-D5, achromycin-D6, olaquindox-D4, amoxicillin-13C6 and trimethoprim-D3; (2) enriching and purifying target antibiotics by using a solid-phase extraction column; (3)detecting the contents of the 15 antibiotics in seven categories in the aquaculture water body with a liquid chromatograph/mass spectrometer by adopting an internal standard method. The method provided by the invention has the benefits that with the adoption of a single-factor experiment, the residue situations of the 15 antibiotics containing 8 new antibiotics in the aquaculture water body can besimultaneously detected at a time by preferably selecting the internal standard substances and optimizing detection conditions; the method has the advantages of high precision, high sensitivity, highstability, high selectivity, low detection limit, more true and reliable detection results and the like.

The invention discloses a method for extracting and detecting polyphenol in bamboo shoots. The method comprises the following steps: (1) preparing materials, namely, selecting fresh bamboo shoots, freezing in liquid nitrogen, knocking to shell, and preserving the bamboo shoot meat at minus 70 DEG C for later use; (2) selecting acetone as an extraction solvent, and extracting polyphenol in the bamboo shoots through an ultrasonic low-temperature auxiliary solvent; (3) detecting by using a Folin-ciocalteu method, wherein the detection system comprises 0.25ml of polyphenol extracting solution, 1.75ml of water, 1ml of Folin-ciocalteu color developing agent which is diluted for 6 times and 1ml of 5-15% Na2CO3; the detection condition is that the reaction temperature is 25-35 DEG C in water bath, the reaction time is 0.5-3.5 hours, and the detection wavelength is 755-770nm. Due to adoption of the method, a system for detecting the polyphenol in fresh bamboo shoots and a system for extracting the polyphenol in the bamboo shoots are optimized and established, the detection is rapid and convenient, the extraction efficiency is high, and theoretical foundation can be provided for bamboo shoot development and utilization.

The invention discloses a kit for identifying donkey hide, horse hide and mule hide on basis of a MGB probe and a detecting method thereof. The kit includes PCR (polymerase chain reaction) reaction liquid for real-time fluorescent quantitation PCR detection; the PCR reaction liquid includes a donkey and horse ckm gene general primer ckm-F/ckm-R, a donkey MGB probe MGB-Lv, a horse MGB probe MGB-Ma, a quality control primer, a quality control probe, Taq DNA (deoxyribonucleic acid) polymerase, anhydrous D-(+)-mycose, KCI, MgCl2, dNTPs, glycerinum, bovine serum albumin and ROX reference dye. The MGB probe technique is innovatively used; the MGB probe and template DNA can be completely combined, so that the stability is better; the result is more accurate. In addition, the kit has the advantages that the ingredients of the reaction liquid are optimized, so that the technical quality requirements on detection personnel are lowered; the practical operation steps are simplified; the practical application of colla corii asini production enterprises is convenient.

The invention provides a rapid detection method for alkannin. The method comprises the steps of 1, sample preparation, 2, PY-GC/MS detection and 3, data analysis and qualitative and quantitative analysis. The PY-GC/MS technology is selected for detecting the content of alkannin in lithospermum, the rapid and microcrystalline detection method for alkannin is provided for solving the problems that qualities of the alkannin in actual production and living are different due to different producing areas, seasons and processing methods, and then the alkannin or the quality of the alkannin compound preparation is preliminarily judged. The rapid detection method has the advantages of being easy to implement, low in detection limit, good in experiment reproducibility and visual and reliable in experimental data, is particularly applicable to micro-sample detection, and can be used for preliminary comparison of quality differences of alkannin or alkannin compound preparation samples of different producing areas, varieties, batches and manufacturers, the application range is wide, and the preliminary judgment basis is provided for quality standard and modernization application of alkannin or alkannin compound preparations.

The invention provides a high-performance liquid chromatography for detecting the residual amount of matrine in tobacco. The high-performance liquid chromatography comprises the following steps that (1) preparing a standard matrine solution, including weighing a standard matrine of a certain mass, dissolving with methanol, titrating to obtain a standard stock matrine solution, and diluting the standard stock matrine solution stepwise to obtain standard work solutions with a series of concentration gradients; (2) extracting, including extracting the matrine in tobacco by using dichloromethane as an extracting agent; (3) purifying, including purifying an extract by using an alumina SPE (solid phase extraction) columella; (4) detecting by using the liquid chromatography; (5) establishing a standard curve; and (6) computing and analyzing the matrine residue. The high-performance liquid chromatography provided by the invention is characterized by being simple, accurate, rapid and reliable and is of great importance to controlling the residual amount of matrine in tobacco and guiding the safe and reasonable application of matrine to tobacoo.

The invention belongs to a technology of assembling an aero-engine, and relates to a centering and rotating device for assembly of a high-pressure compressor of an engine. The centering and rotating device is characterized by comprising a mandrel (1), a base mandrel (2), an adjusting sleeve (3), an adjusting nut (4), a pressing nut (5), n' steel balls (6), a positioning pin (20), n set screws (21) and screws. During assembling of the high-pressure compressor of the aero-engine, a gap m between a rotor (13) and a compressor shell (11) can meet a design requirement, the rotor (13) can flexibly rotate in the compressor shell (11), the requirement on follow-up circumferential detection of the rotor (13) and blades is met, and meanwhile, a clamp is convenient to assemble and disassemble when used.

The invention provides a determination method for the reaction activity order of active hydrogen-containing components and a curing agent in a propellant, wherein the method is applied to the field of nuclear magnetic analysis of spaceflight fuels. The method comprises the following steps: determination of a detection object; preparation of detection samples; selection of detection conditions; implementation of sample detection; and processing of detection data. According to the invention, a mixed uniform system of active hydrogen-containing components and toluene diisocyanate (TDI) in the propellant is taken as the detection object. To prepare the samples, groups are proportioned according to concentrations, grouped and then uniformly mixed; and a proper amount of the samples are selected and placed in a chromatographic bottle. A low-field nuclear magnetic resonance spectrometer is employed, and the detection conditions are selected. The changing curve of spin-spin relaxation time T2 with reaction time is detected, each vertical coordinate of the curve is normalized, and the reaction activity order of each component and TDI is acquired according to the speed of slope changes before the curve tends to be flat. The determination method provided by the invention has the advantages of simple operation, safety in experiments, reduction in cost, reliable experimental data, optimized detection conditions and simplified detection process.

The invention discloses a method for detecting a human soluble asialoglycoprotein receptor (sASGPR), and belongs to the field of immunological detection. The ELISA method for detecting the human sASGPR is economical, fast, accurate and high in practicability. According to the method, on the basis of a specific ligand of the ASGPR and specific identification of the ASGPR, a galactosylated serum albumin (GSA) is selected as the specific ligand of the ASGPR, the GSA is prepared from human serum albumin and has the advantages of being low in cost, easy to prepare, easy to preserve and the like, the detection limit of the method is applicable to detection of the sASGPR in a human serum sample, special and large instruments and equipment do not need to be used, and the method can be carried outin an ordinary laboratory, has the advantages of being high in specificity, good in stability, easy and convenient to operate, low in cost and the like, and provides certain reference value for clinical liver function assessment.

The invention provides a rapid detection method for psoralen and isopsoralen. The method comprises steps as follows: 1) preparation of samples; 2) PY-GC/MS (pyrolysis-gas chromatography/mass spectrum) detection; 3) data analysis as well as qualitative and quantitative analysis. A PY-GC/MS technology is selected for detecting the content of the psoralen and the isopsoralen, according to the problem of different quality due to differences in origins, seasons, preparation methods and the like of Chinese angelica in actual production and life, the rapid and trace detection method for the psoralen and the isopsoralen is provided, and then the quality of fructus psoraleae is preliminarily judged; the method has the characteristics of simplicity in operation, low detection limit, good experimental reproducibility, direct and reliable experimental data and the like, is particularly applicable to trace sample detection, can be used for preliminarily comparing quality differences of different varieties and different batches of fructus psoraleae samples from different origins, is wide in application range and provides a preliminary judgment basis for the quality standard and the modernization application of the fructus psoraleae.

The invention provides a method for determining the content of methanol in air of a work place. The method comprises the following steps: collecting an air sample by using a silicone tube, dissolving the air sample by pure water, carrying out static headspace sample introduction, and detecting through a gas chromatograph (an FID detector). The method is mainly used for detecting the content of methanol in air of the work place.

Provided is a determination method of formaldehyde-DNA adducts in saliva, namely the determination method of HOMe-dA and HOMe-dG in the saliva; the determination method includes the steps: collecting the saliva by using an OG-500 saliva collection tube, carrying out DNA extraction on the saliva, carrying out enzyme hydrolysis of the DNA solution, and successively adding a stable isotope internal standard, a reducing agent NaBH3CN and a DNA hydrolase; and carrying out solid-phase extraction of the hydrolysate with a Strata-X small column, collecting an eluted liquid, nitrogen-blowing to be dried at room temperature, redissolving in a methanol aqueous solution, introducing into an LC-MS/MS system, analyzing, and accurately detecting the content levels of Me-DA and Me-dG. The stable isotope is used as an internal standard quantitative analysis material, so the error caused by the sample pretreatment process can be reduced, and the selectivity, accuracy and sensitivity of the method can be improved by tandem mass spectrometry. Through selection and optimization of the chromatographic column and the elution conditions, the chromatographic separation process is relatively improved, the time of chromatographic analysis is shortened, and the consumption amount of an organic solvent is decreased.