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1292 results about "Sample extraction" patented technology

Methods and apparatus of downhole fluid analysis

Methods and apparatus for downhole analysis of formation fluids by isolating the fluids from the formation and / or borehole in a pressure and volume control unit that is integrated with a flowline of a fluid analysis module and determining fluid characteristics of the isolated fluids. Parameters of interest may be derived for formation fluids in a static state and undesirable formation fluids may be drained and replaced with formation fluids that are suitable for downhole characterization or surface sample extraction. Isolated formation fluids may be circulated in a loop of the flowline for phase behavior characterization. Real-time analysis of the fluids may be performed at or near downhole conditions.
Owner:SCHLUMBERGER TECH CORP

Repetitive circumferential milling for sample preparation

A method of sample extraction entails making multiple, overlapping cuts using a beam, such as a focused ion beam, to create a trench around a sample, and then undercutting the sample to free it. Because the sidewalls of the cut are not vertical, the overlapping cuts impinge on the sloping sidewalls formed by previous cuts. The high angle of incidence provides a greatly enhanced mill rate, so that making multiple overlapping cuts to produce a wide trench can requires less time than making a single, deep cut around the perimeter of a sample.
Owner:FEI CO

Preparation and application of electrochemiluminescence sensor for detecting trace pesticide residue

The invention discloses an electrochemiluminescence sensor for detecting trace pesticide residue and a method for detecting pesticide residue. An electrode preparation method (figure attached) comprises the following steps: selecting an identifier of the pesticide residue; preparing quantum dots and graphene nano material according to documents; and modifying the nano material, the quantum dots and the identifier onto the electrode surface of the sensor by the electrode surface modification technology. The method for detecting the trace pesticide residue comprises the following steps: connecting the modified electrode to an electrochemiluminescence instrument and detecting the pesticide residue in the sample extract. The electrode in the invention has high specificity and sensitivity capable of reaching ng level, a basic detection process is finished only within 3-5 min, and the cost is low. The method for detecting the pesticide residue by utilizing the electrode is fast and simple to operate, and the reaction is automatically finished and the result is automatically recorded by an apparatus.
Owner:UNIV OF JINAN

Sample Metering Device and Assay Device with Integrated Sample Dilution

In one embodiment, the invention is to a sample metering device, comprising a sample holding chamber oriented between a sample entry port and a sample extraction unit, wherein a portion of said extraction unit defines a metered volume of a sample. A diluent may be transported over and / or through the extraction unit to form a diluted sample for sample analysis. In another embodiment, the invention is to an apparatus and method for rapid determination of analytes in liquid samples by various assays including immunoassays incorporating a sample dilution feature, capable of being used in the point-of-care diagnostic field is provided. The devices and methods of the invention preferably are well-suited for high range sample dilution.
Owner:ABBOTT POINT CARE

Repetitive circumferential milling for sample preparation

A method of sample extraction entails making multiple, overlapping cuts using a beam, such as a focused ion beam, to create a trench around a sample, and then undercutting the sample to free it. Because the sidewalls of the cut are not vertical, the overlapping cuts impinge on the sloping sidewalls formed by previous cuts. The high angle of incidence provides a greatly enhanced mill rate, so that making multiple overlapping cuts to produce a wide trench can requires less time than making a single, deep cut around the perimeter of a sample.
Owner:FEI CO

Method and apparatus for sample extraction and handling

An improved method and apparatus for extracting and handling samples for S / TEM analysis. Preferred embodiments of the present invention make use of a micromanipulator and a hollow microprobe probe using vacuum pressure to adhere the microprobe tip to the sample. By applying a small vacuum pressure to the lamella through the microprobe tip, the lamella can be held more securely and its placement controlled more accurately than by using electrostatic force alone. By using a probe having a beveled tip and which can also be rotated around its long axis, the extracted sample can be placed down flat on a sample holder. This allows sample placement and orientation to be precisely controlled, thus greatly increasing predictability of analysis and throughput
Owner:FEI CO

Device and method for soil hydraulic permeability measurement

A permeameter apparatus and method of measuring hydraulic permeability of porous samples, that includes multiple tube manometers stacked vertically at equal intervals on the same side wall of a compression cell containing the sample. The levels of the water menisci in the stacked manometers characterize the temporal and spatial profile of hydraulic conductivity, which can be measured in the constant and falling head regimes in the same apparatus. The apparatus is enabled with a sample compression system imitating the geostatic pressure profiles at different depths of the sample extraction. The apparatus and method allow measurement of time-dependent hydraulic conductivity in anisotropic media at variable pressures.
Owner:PRINCE MOHAMMAD BIN FAHD UNIV

Method for measuring glycerinum and 1,2-propylene glycol in cigarettes, electronic cigarettes and low-temperature cigarettes

InactiveCN103698431AQuality improvementIndustry standard for perfect monitoringComponent separationGlycerolBottle
The invention discloses a method for measuring glycerinum and 1,2-propylene glycol in cigarettes, electronic cigarettes and low-temperature cigarettes. The method comprises cigarette suction, smoke capturing, sample extraction and instrumental analysis and specifically comprises the steps: (1) sucking the cigarettes, the electronic cigarettes and the low-temperature cigarettes through a range hood; (2) capturing components to be measured in mainstream smoke through a Cambridge filtering disk or an absorption bottle; (3) adding a solvent into the Cambridge filtering disk with the components to be measured for extraction; (4) filtering an extracting solution or an absorption solution in the absorption bottle for analysis and determination through an instrument. The method is high in reproducibility and high in analysis sensitivity and can be used for accurately and quantitatively analyzing the glycerinum and the 1,2-propylene glycol in the cigarettes, the electronic cigarettes and the low-temperature cigarettes. The method is easy to operate, and a measurement result is accurate; therefore, the industrial standard for evaluation and monitoring of the quality of a cigarette product is further perfected.
Owner:YUNNAN RES INST OF TOBACCO SCI

Method for identifying animal-based components in meat and meat products by utilizing SDS-PAGE (Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) method

InactiveCN102213720APrevent incomingPrevent concealmentTesting foodMuscle tissueBiology
The invention relates to a method for identifying the animal-based components in meat and meat products by utilizing an SDS-PAGE (Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) method, and belongs to the field of food sanitation inspection. The method provided by the invention is utilized to identify the pig, cattle, sheep, chicken and fish-based components in the meat products; the SDS-PAGE is carried out on the soluble proteins which are extracted from the processed sample by carrying out different temperature thermal treatments on fresh animal muscle tissues; and the pig, cattle, sheep, chicken and fish-based components in the meat products are judged according to an electrophoresis pattern. The method provided by the invention has the characteristics of strong specificity and sensitivity, and visual and reliable result judgment, and is simple to operate and has the extremely important significances on preventing animal disease pathogens such as foot-and-mouth disease, avian influenza and the like from spreading into China, preventing illegal retailers from concealing commodity components and guaranteeing the health of people.
Owner:QINGDAO AGRI UNIV +1

Preparation of ECL (electro chemical luminescence) DNA (Deoxyribose Nucleic Acid) sensor based on 3D paper chip, and application of sensor to simultaneous detection on Hg<2+> and Ag<+>

The invention discloses preparation of an ECL (electro chemical luminescence) DNA (Deoxyribose Nucleic Acid) sensor based on a 3D paper chip, and application of the sensor to simultaneous detection on Hg<2+> and Ag<+>. The preparation method of the sensor (the schematic diagram of which is shown in the figure) comprises the following steps of: designing a micro-fluidic chip pattern on a computer, and preparing a 3D paper chip sensor; preparing nano materials such as a porous gold nanowire, PdAg alloy, a carbon point and P acid according to existing methods, preparing PdAg@CQDs and PdAg@P-acid with signal amplification functions as ECL probes, and respectively compounding the ECL probes with DNA subjected to specific binding with Hg<2+> and Ag<+>; and modifying the porous gold nanowire to the surface of an electrode of the sensor by an electrode surface modifying technology, and absorbing a DNA segment to prepare the DNA sensor. The method for simultaneously detecting Hg<2+> and Ag<+> comprises the following steps of: connecting the modified electrode to an ECL apparatus, and detecting Hg<2+> and Ag<+> in a sample extracting solution. The electrode of the sensor is strong in specificity and high in sensitivity, and is capable of reaching a p mol level. When the paper chip sensor easily processed is used for simultaneously detecting two materials on the same electrode, the detection efficiency is improved, and the cost is lowered.
Owner:UNIV OF JINAN

Low Pressure Biogas Sample Takeoff and Conditioning System

A temperature and pressure regulating biogas sample extraction system and method for providing a conditioned biogas sample for constituent analysis.
Owner:MUSTANG SAMPLING

Preparation method and application of molecular imprinting electroluminescent sensor for detecting trace veterinary drug residue by taking battery as power

The invention discloses a molecular imprinting electroluminescent sensor for detecting veterinary drug residue by taking a battery as power and a method for detecting veterinary drug residue. A preparation method of an electrode (a schematic diagram is shown in the figure) comprises the following steps of: preparing MIP (Molecularly Imprinted Polymer)s sol of the veterinary drug residue; preparing a carbon dot and preparing a graphene nano material according to documents; and modifying graphene, the carbon dot and the MIPs sol onto the surface of the electrode of the sensor. The method for detecting the trace veterinary drug residue comprises the following steps of: connecting the modified electrode to an electrogenerated chemiluminescence instrument, and detecting the veterinary drug residue in a sample extract by taking the battery as the power. The molecular imprinting electroluminescent sensor disclosed by the invention has the advantages that the specificity of the electrode is strong and the sensitivity is high and can be up to a ng grade; only 3-5 minutes are spent on a basic detection process; and the cost is low. The method for detecting the veterinary drug residue by adopting the electrode is quick and easy to operate, the reaction is automatically completed by instruments and results are automatically recorded by the instruments.
Owner:UNIV OF JINAN

High performance liquid chromatography detection method for residual quantity of multiple ultraviolet absorbents in cosmetics

The invention relates to the field of analytical chemistry and food safety, and provides a high performance liquid chromatography detection method for residual quantity of multiple ultraviolet absorbents in cosmetics. A cosmetic sample of 0.4g is weighed and placed in a plastic centrifuge tube of 50 ml, sample extraction liquid of 20ml is added, after the cosmetic sample of 0.4g and the sample extraction liquid of 20ml are mixed for 2 minutes in a vortex mode, sonic oscillation extraction is carried out for 20 minutes, 8000 revolutions per minute centrifugation is carried out for 10 minutes and, and supernate is to be purified; and after test solutions sequentially pass through microfiltration membranes of 0.45 micrometer and 0.20 micrometer, a high performance liquid chromatograph is adopted to carry out qualitative determination and quantitative assay. The detection method has the advantages of being simple, fast, accurate, efficient, and the like, and can detect 12 ultraviolet absorbents at the same time. Technical indexes of detection minimum, the recovery rate, the degree of precision, and the like all meet relevant demands for ultraviolet absorbent detection in sun block cosmetics at home and abroad. The method is suitable for detection and monitoring of the ultraviolet absorbents in the sun block cosmetics, and has great significance on promoting of import and export trade of cosmetics of our country, ensuring of safety of the cosmetics, and guarantee of human body health.
Owner:林维宣

Non-Condensing Gas Sampling Probe System

A system for measuring water and / or gaseous phase content of high temperature process gases includes a probe for gas sample extraction and cooling temperatures below those which probe filter or gas analyzer components degrade. A heated gas extraction tube provided within the probe interior operates to maintain the thermal stability of the cooled gas sample to preserve chemical integrity.
Owner:TENOVA GOODFELLOW INC

Extraction purifying measuring method of polycyclic aromatic hydrocarbons in soil

The PAHs extraction purification determination method in the soil relates to 18 trace PAHs analysis and determination method in the soil. Using automatic Soxhlet extraction instrument to extract PAHs organic in the soil samples, and then using silica gel column chromatography to purify the extracted liquid, remove the polar and non-polar interference during extraction, and finally, using HPLC (with diode array detector) to analyze qualitatively and quantitatively 18 PAHs. In this invention, the extraction solvent consumption is small, and it can be used for large volume sample extraction, with quick sample analysis speed, low-cost sample pretreatment, and for the 5 group 13 isomers in 18 PAHs, it can not only accurately qualitatively but also accurately quantitatively determine, with low detection limit, high sensitivity, and with the exception of fluorine and perylene, the detection limit of the other 16 PAHs all below 10ng / g-dw. It is a rapid, sensitive and accurate analytical method for the trace PAHs, applied to farmland, wasteland, urban green belt and other soil.
Owner:TONGJI UNIV

Liquid chromatography for synchronously detecting 15 anabolic hormone residues in food

The invention relates to a liquid chromatography for detecting anabolic hormone drug residue in animal-derived food, which is characterized by first sampling: animal musculature is taken off the fat and connective tissue, then minced and evenly ground, and the sample is weighed; extracting: anabolic hormone extract is extracted from the weighed sample by methanol ultrasonic extraction, the extract is evaporated to dryness in water bath through a rotary evaporator, and the residue is dissolved by methanol aqueous solution; purifying: C18 Solidoid extraction column on the extract is carried out solid phase extraction; and testing by devices: the filtrate is tested by opposite phase high efficiency liquid chromatography, quantified by external reference method-peak area, and then carried out with binary gradient elution. In the invention, the detected sample is complex biological sample; the established method can complete one detection in about one hour and is simple and fast, with reliable sensitivity and low cost; the method can analyze more veterinary hormone drug species than the synchronous usage of the existing GC or HPLC methods with easier operation, and has lower cost than the existing GC / MS and LC / MS or LC / MS / MS methods with low solvent toxicity.
Owner:上海国矗生物科技有限公司

Database migration data verification method and system

The invention discloses a database migration data verification method and system. The system comprises various source databases and target databases. The method comprises that a data segmentation module extracts data from the source databases and the corresponding target databases to form sample data blocks of data verification. A data block management module performs data attributive analysis on the sample data blocks to form sample data block basic information and compares the block basic information of the source databases with corresponding target database basic information to obtain the conclusion of the integrity of migration data. By means of the method and the system, the block basic information obtained through sample extraction by the source databases and the target databases is compared to verify the database migration data, and accordingly, the loads of former comparison of a large number of data are reduced greatly.

Detection method for residual quantity of multiple preservatives in cosmetics

The invention relates to the field of analytical chemistry and food safety, in particular to a detection method for residual quantity of multiple preservatives in cosmetics. According to a gas chromatography-mass-spectrography detection method which can detect the residual quantity of multiple preservatives in cosmetics simultaneously, sample extraction and purification are respectively processed according to differences of sample shapes and properties, and then a gas chromatography-mass spectrometer is adopted to carry out qualitative determination and quantitative assay. The detection method achieves simultaneous detection of 21 preservatives, and has the advantages of being simple and convenient, fast, sensitive, and the like. The detection minimum, the recovery rate and the degree of precision of the method all meet relevant demands for preservative detection in the cosmetics at home and abroad, so the method is suitable for detection and monitoring of the preservatives in the cosmetics.
Owner:林维宣

Detection method of determining 16 types of photoinitiators in paper printing and packaging material

The invention relates to a detection method of determining 16 types of photoinitiators in a paper printing and packaging material, which is used for determining residual amounts of the 16 types of photoinitiators of 2-hodroxy-2-methyl-1-phenylacetone, mehtyl phenylglyoxylate, benzophenone and the like and is characterized by comprising the following concrete steps of: a, sample pretreatment; b, preparation of a standard work solution; c, instrumental analysis; and d, result calculation. Compared with the prior art, through sample pretreatment and optimization of instrumental analysis conditions, the detection method has the advantages that efficiency is high, the 16 kinds of photoinitiators can be simultaneously analyzed and determined within 25m; and printing ink impurities in a sample extraction solution can be better removed in a liquid-liquid distribution impurity removal mode adopted in the sample pretreatment process, so that cost is low, consumption is little, efficiency is high, and sensitivity is high; and in addition, the detection method also has the advantages of high accuracy and good repeatability.
Owner:CHINA NAT TOBACCO QUALITY SUPERVISION & TEST CENT

Method for rapidly identifying rice black-streaked dwarf virus and southern rice black-streaked dwarf virus

The invention provides a method for rapidly identifying the rice black-streaked dwarf virus and southern rice black-streaked dwarf virus, belonging to the field of plant protection. Three primers are designed according to the nucleotide sequence of the rice black-streaked dwarf virus and southern rice black-streaked dwarf virus, which are respectively [A] RB1_S9_F, [B] RB2_S9_F and [C] RB_S9_R, wherein the combination of A and C detects the rice black-streaked dwarf virus and the combination of B and C detects the southern rice black-streaked dwarf virus. After the total RNA is extracted fromthe samples, the two viruses of the rice black-streaked dwarf virus and the southern rice black-streaked dwarf virus can be detected by only one RT-PCR, thus realizing the identification of two viruses. Compared with the traditional method in which one RT-PCR can only detect one virus, the invention greatly reduces cost, reduces time, and is a detection method which is special, sensitive, economic and convenient.
Owner:JIANGSU ACADEMY OF AGRICULTURAL SCIENCES

Preparation for molecularly-imprinted electroluminescent paper chip for detecting multiple sample pesticide residues

The invention discloses a preparation for a molecularly-imprinted electroluminescent paper chip for detecting multiple sample pesticide residues. The preparation method of the sensing paper chip comprises the following steps: preparing an MIPs sol of a pesticide residue molecule; preparing a tridimensional graphene gold nanometer composite material; preparing a g-C3N4 quantum dot; and utilizing an electrode modification technology to modify the electrode surface of the sensing paper chip with the tridimensional graphene gold nanometer composite material, the g-C3N4 quantum dot and the MIPs sol. A method for detecting multiple sample pesticide residues comprises the following steps: connecting the modified sensing paper chip to an electrochemical workstation, and cooperating with a chemiluminescence apparatus to detect pesticide residues in a sample extraction solution. The prepared paper chip is strong in electrode specificity and high in sensitivity, and has the sensitivity up to nanometer gram grade. A detection process only takes 3-5 min, and the cost is low. The electrode detection method for pesticide residues is simple and rapid in operation, and reactions and results are automatically finished and recorded by an instrument.
Owner:UNIV OF JINAN

Detection method of multiresidue of 5 nitrofuran metabolites and chloramphenicol in shrimp

ActiveCN106124653AImprove extraction efficiencyOvercoming the limitations of separate assaysComponent separationMetaboliteQuantitative accuracy
A detection method of a nitrofuran metabolites and chloramphenicol multiresidue in shrimp belongs to the technical field of aquatic products detection. The method is as below: hydrolyzing a sample with hydrochloric acid, subjecting nitrofuran metabolites to derivatization by using 2-nitrobenzaldehyde, adjusting the pH value to 6.5-7.5, adding acetonitrile, adding an extraction salt package; conducting liquid-liquid extraction of a target compound by using acetonitrile; purifying and concentrating a supernatant; then determining by a liquid chromatography-tandem mass spectrometer, and quantifying by an internal standard method. The method uses a novel sample extraction and purification mode for simultaneous analysis and determination of two prohibited drugs with the highest detection rate in shrimp, overcomes the limitations of separate determination of two drugs in the detection method of the prior art, improves the extraction efficiency of chloramphenicol in actual positive samples, greatly improves the work efficiency, shortens the work time and saves reagent consumption and labor costs. The method adopts the isotope internal standard method for quantification, the determination result is more accurate and reliable, has high sensitivity, and good reproducibility and quantitative accuracy.
Owner:青岛菲优特检测有限公司

Method and equipment for detecting middle guiding code sequence in TD-SCDMA system

It is a kind of Midamble code sequence detection method and apparatus for TD-SCDMA mobile communication system. It can reach high detection probability and low missing probability under the condition of low signal-to-noise ratio and the under the environment of having frequency diffusion and time diffusion. It can also generate rejection mark and exclude a batch of wrong input incident, such as wrong code set sequence number input, wrong synchronous Information input and local oscillator has large frequency deviation, so to realize the reduction of initializing community research time in TD-SCDMA system. This invention includes the module and steps such as Midamble receives signal sample extraction, Midamble code sequence generation, slide association, delay envelope calculation, multi-frame combination, path selection, similar value calculation, maximum value detection, confidence level calculation and compare, the generation of detection rejection mark, and generation of detection Midamble code sequence number.
Owner:XUANPU INDUSTRY CO LTD

Self-cleaning sample extraction system

A sampling apparatus for use with a sample analyzer comprises a sample probe insertable into a process stream, and an extraction cylinder including a variable volume chamber and a piston movable by an actuator back and forth in the cylinder to increase and decrease the volume of the variable volume chamber. A sampling valve is connected between the extraction cylinder and the sample probe, with a sample line connecting the sampling valve to the sample probe, and the variable volume chamber having a capacity substantially greater than the combined volumes of the sample probe, sampling valve and sample line. A filter assembly is interposed between the sample probe and sampling valve for filtering undesired substances from the fresh sample prior to the fresh sample reaching the sampling valve, and a controller is provided for controlling the actuator and the sampling valve, first to move the piston at a first rate to increase the variable volume chamber sufficiently to draw fresh sample from the process stream and past the sampling valve, then to operate the sampling valve for injecting fresh sample into the sample analyzer, and thereafter to move the piston at a second rate greater than the first rate to decrease the variable volume chamber to flush excess sample back into the process stream and clean the filter of undesired substances filtered from the fresh sample.
Owner:PARKER INTANGIBLES LLC

Determination method of benzo(a)pyrene in Camellia oleifera seed oil

InactiveCN102288720AAccurate analysisSusceptible to outside interferenceComponent separationEnvironment effectFood safety
The invention discloses a method for detecting benzo(a)pyrene in Camellia oleifera seed oil, belonging to the technical field of food safety detection. It includes steps such as sample extraction, purification and qualitative and quantitative analysis. The invention adopts a stable high-performance liquid chromatography method, is less affected by the external environment, can accurately quantitatively analyze, and has a detection limit of 1 μg / kg. The invention adopts a saponification method to change the properties of the oil matrix, and then purifies it with an alumina purification column, so that a better purification effect can be achieved even if the sampling amount is increased.
Owner:RES INST OF SUBTROPICAL FORESTRY CHINESE ACAD OF FORESTRY

Determination method of residual amount of glufosinate, glyphosate and aminomethyl phosphoric acid in food

The invention discloses a determination method of residual amount of glufosinate, glyphosate and aminomethyl phosphoric acid in food. The determination method of residual amount of glufosinate, glyphosate and aminomethyl phosphoric acid in food comprises the following steps: in the sample pretreatment, firstly, extracting glufosinate, glyphosate and aminomethyl phosphoric acid in a food sample by a methanol water solution in sample pretreatment; then purifying an extracting solution by selecting a C18 dispersive solid-phase extraction agent; and finally, filtering, deriving, and determining three compounds qualitatively and quantitatively synchronously by combining with high performance liquid chromatography-tandem mass spectrum. According to the method provided by the invention, the operation is simple and convenient, and the reproducibility is good, and impurities in a sample extraction solution can be removed effectively; the pretreatment is the supplement and improvement of the existing QuEChERS method; the recycling rate can reach 70.5%-91.2%; the relative standard deviation is 4.5%-7.83%; the limit of quantification is 50micro-g / kg; the determination method can completely meet the technical requirement on safety detection of China, European Union, America and Japan, and can provide powerful technical support for food safety and export trade healthy development for people of China.
Owner:INSPECTION & QUARANTINE TECH CENT SHANDONG ENTRY EXIT INSPECTION & QUARANTINE BUREAU

Method for measuring pesticide residue quantity in leather

The invention relates to a combined gas chromatography mass spectrometry measuring method for measuring the pesticide residue in leather, which belongs to the field of analytical chemistry. The method adopts normal hexane and acetonitrile to perform ultrasonic extraction to a leather sample and separates and purifies the sample extracting solution by various means such as liquid-liquid extraction, gel permeation chromatograph, adsorbent chromatography column, solidoid extraction column, and the like by aiming to the characteristics that the leather sample has high oil content, the residual processing assistant is complex, and the like, and the pesticide residue of the processed sample extracting solution is measured by the combined gas chromatography mass spectrometry. The invention has the advantages of high selectivity, wide range of application and low detectability, realizes the measurement of the pesticide residue in the leather, creates a new thought for the measurement of the pesticide residue in the leather and fills in a gap for the measurement of the pesticide residue.
Owner:通标标准技术服务(天津)有限公司
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