67results about How to "Analytical methods are accurate and reliable" patented technology

The present invention aims to provide a method for determining vitamin A and E in animal-derived food. Specifically, the invention employs the solid phase extraction and high performance liquid chromatography coupling technique to establish an on-line solid phase extraction-high performance liquid chromatography analytical method for simultaneous determination of vitamin A and vitamin E in animal-derived food. Furthermore, the invention also provides an on-line solid phase extraction analysis system for the detection of vitamin A and vitamin E.

The invention provides a near infrared spectrum qualitative identification method of pearl powder and shell powder. The near infrared spectrum qualitative identification method comprises the following steps of firstly, collecting near infrared spectrograms of a plurality of pearl powder samples and a plurality of shell powder samples as a pearl powder correction set and a shell powder correction set; then, establishing a discrimination analysis model by virtue of near infrared spectrum analysis software for setting model parameters according to the correction sets, wherein optical length types are selected for multi-element signal correction, spectrum pre-treatment is performed by virtue of a second derivative, smoothness is performed by virtue of Norris derivative filtering, a correction spectrum region is in a range of 4100-9800 cm<1> and the like; and finally, by virtue of the near infrared spectrograms of the samples to be detected and the established discrimination analysis model, analyzing the mahalanobis distance between the near infrared spectrograms of the samples to be detected and the pearl powder correction set, and the mahalanobis distance between the near infrared spectrograms of the samples to be detected and the shell powder correction set, and automatically giving an identification result by the near infrared spectrum software. The near infrared spectrum qualitative identification method provided by the invention is simple, convenient, fast and reliable.

The invention discloses a method for testing the water content of foamed asphalt, and relates to material testing or analysis with nuclear magnetic resonance. The water content of the foamed asphalt is measured by a nuclear magnetic resonance device. The method comprises the following steps: preparing a foamed asphalt test sample of which the water content is to be tested; setting a nuclear magnetic parameter of the nuclear magnetic resonance device; acquiring a nuclear magnetic resonance semaphore of each gram of asphalt from which impurities are removed; determining a relationship between the water content of a standard test sample and a nuclear magnetic resonance semaphore; acquiring a total nuclear magnetic resonance semaphore of the foamed asphalt test sample of which the water content is to be tested; acquiring the mass of foamed asphalt evaporation residues in the foamed asphalt test sample of which the water content is to be tested; calculating the water content of the foamed asphalt test sample of which the water content is to be tested. According to the method, the defect of incapability of a method in the prior art to measurement of the water content of the foamed asphalt and the defects of an industrial CT method, disclosed in CN103558236A, for testing the water distribution of an asphalt mixture are overcome.

The invention provides a determination method for calcium, cobalt, chromium and iron in tungsten carbide. The method employs inductively coupled plasma atomic emission spectrometry for determination of the content of calcium, cobalt, chromium and iron in tungsten carbide, and analytical ranges are as follows: Ca 0.005 to 2%, Co 1 to 15%, Cr 1 to 15% and Fe 0.005 to 10%. According to the invention, a tungsten carbide sample can be effectively dissolved, so the problem of difficult dissolution of the sample is overcome and a sample dissolution speed is accelerated; an optimal analytical line is found through interference experiments and spectrum analysis, interference among spectral lines is eliminated, accurate and reliable determination of the content of calcium, cobalt, chromium and iron in tungsten carbide is realized, and requirements of scientific research and production are met; and the method has the advantages of rapid measurement, easy and convenient operation and conservation of considerable manpower and material resources.

The invention discloses an analysis method for amide compounds. The analysis method adopts a gas chromatography-mass spectrometry method. According to the invention, under the optimized analysis conditions, very good chromatographic peaks of the five amide compounds can be obtained within 15 min; very good separating effects can be obtained; the linearities of all the target compounds are good within a concentration range of 0.01-10 mg / L; the correlation coefficients are all greater than 0.9995; the detection limits reach 0.01 mg / kg; the relative standard deviations are smaller than 2.5%; the recovery rates of standard addition are 80-105%. The analysis method is convenient, fast, accurate, and reliable, and can meet REACH regulation requirements on hazardous amides.

The invention relates to a method for discriminating Chinese mitten crabs in different producing areas, which is characterized by comprising the following steps of: fishing for the Chinese mitten crabs in different producing areas and then placing in a refrigerator for preservation; after thawing the crabs, taking the third ambulatory legs at the left sides of crab carapaces for element analysis,and then drying the third ambulatory legs in a drying oven to the constant weights; grinding dry samples by using agate mortars for homogenization, and then placing in the drying oven at room temperature; weighing and placing the dry samples into a digestion pipe, and adding concentrated nitric acid to the digestion pipe for digesting the dry samples; transferring the digested samples into a quantitating bottle, and then determining the volume of the samples by using pure water to obtain a solution to be measured; measuring the concentration values of trace elements in the solution to be measured and calculating the corresponding concentration values in the third ambulatory leg dry samples of the Chinese mitten crabs. The analysis method in the invention has reliability and favorable precision, and can effectively discriminate Chinese mitten crab crowds respectively produced in the Jiangsu Yangcheng Lake, the Yong Lake, the Changdang Lake and the Jiangxi Junshan Lake and establish a specific trace element geographical fingerprint library and a discrimination function equation of the Chinese mitten crabs in various areas.

Accurate, dependable methods for analyzing operational parameters of subsea control systems and diagnosis / prediction of failures are provided, in particular, methods for detection of leaking and / or clogging in hydraulic control system using recorded pressure signals and evaluating response communication strength (signal amplitude) of field equipment from, for example, subsea control systems. Prediction of failure(s) allows an opportunity to prepare for intervention to minimize the impact of failure before failure occurs, for example, by ordering equipment, tools and / or scheduling an intervention vessel. Similarly, diagnosing a failure drastically shortens the intervention time.

The present invention relates to a method for determining a plurality of minor elements in the body of the whitebait from different producing areas. The invention is characterized in that the specimen of the whitebait is transferred into a refrigerator for storing. The specimen of the whitebait is washed with after thawing and is baked to a constant weight in a drying cabinet. The dried specimen of large whitebait is grinded to powder and is arranged in a dryer in pickle. The dried specimen of large whitebait is taken into a Teflon decomposing container which is acid washed. The high purity hydrogen nitrate is added for preparing the acidolysis in room temperature. A microwave oven is used for resolution. Then hyperpure water is used for regulating the volume to a solution to be measured. The solution to be tested is leaded into an inductance coupling plasma velocitron to execute a concentration determination. The concentrations of 11 minor elements in the dried specimen of large whitebait are measured. A linear dicriminant function is established. The large whitebait generated in different waters can be effectively discriminated through the calculated value of the dicriminant function. The result obtained by the invention has the advantages of good stability, high repeatability, small systematical error and strong discriminability. Not only the localizations which can be discriminated by the methods of visual method, hereditism and the like are overcome, but also the predominance of high speed is displayed.

The invention relates to a method for determining vanadium element in vanadium iron alloy. The method is characterized by comprising the steps of oxidizing the vanadium into pentavalence by utilizing potassium permanganate in the existence of a sulfur phosphorus mixed acid medium, reducing the excessive potassium permanganate by utilizing sodium nitrite in the existence of urea, titrating the mixture by utilizing an ammonium ferrous sulfate standard solution and adopting N-phenyl o-aminobenzoic acid as an indicator agent, wherein the determination range is more than 0.5 percent. According to the method, the sample amount is reduced to 0.1g, and the process of dissolving the test sample is changed to comprise the following steps: dissolving a test sample by adding 20mL to 50mL of hydrochloric acid, 5 to 15mL of nitric acid, 10mL of phosphoric acid in a slightly heating manner, adding 30mL of 1+1 sulfuric acid, and heating and evaporating the mixed solution to produce sulfuric acid smoke for 2 to 3 minutes; slightly cooling the mixture, adding 50mL of water, and dissolving salt in a heating manner. Through the improvement, the test sample can be completely dissolved, the sample dissolving time is greatly shortened, and the working efficiency is improved on the premise of not influencing the accuracy of a detection result.

Disclosed is a method for detecting the presence of a thermo-responsive point related with the thermal deformation of a main shaft. By changing the temperature of a heating element, the temperature field distribution of the main shaft is changed. Thermistors and eddy current sensors transmit acquired information to a computer. Then, Labview software is employed to analyze and process the information and fuzzy clustering and linear regression methods are employed to carry out the processing. According to the detecting method provided by the invention, the thermistors can be disposed at places of different radiuses so that if a function relation can be established between the temperature at the places of different radiuses and the deformation of the main shaft, the presence of the thermo-responsive point can be determined; and if the function relation cannot be established, the presence of the thermo-responsive point can be denied. According to the invention, if the main shaft do have the thermo-responsive point, the deformation of the main shaft under different technology conditions can be obtained in a more accurate manner based on the thermo-responsive point so that the controlling quantity of an error compensation control system can be changed based on the deformation of the main shaft under different working conditions, thereby increasing the working precision of the main shaft.

The invention discloses an N-phenyl maleimide HPLC analysis method. The invention uses RP-HPLC method, and HPLC conditions are: chromatography column: C18, 5mum, 150X4.6mm (I.D), the volume ratio of the mobile phase: acetonitrile: water = 40-60:60-40, flow rate: 0.8ml / min, column temperature: 30 deg.C, detection wavelength: 217nm, sample volume: 3-5mul, diluting the determined content sample concentration 50 times, and determining N-PMI and impurity content. The HPLC analysis method of the invention can accurately determine N-PMI main content, and meanwhile, it can accurately determine impurity maleic anhydride and aniline content, providing a simple and reliable analysis method for quality control of N-PMI production process.

The present invention adopts piezoelectric gene diagnosis chip and frequency detection instrument and utilizes multiple PCR technique to make temp. circulation of hydridization-extension-denaturation to amplify, target gene, monitor and obtain the linear relationship of frequency change and target gene concentration, then uses external standard curve to make quantitative analysis. Said apparatus comprises shell body, power supply and its connected circuit, and main body module, analysis, software, sample preparation module, positioning liquid flow module and piezoelectric gene diagnosis chip detection module. Said invention is suitable for clinical diagnosis and molecular mechanism research, monitoring epidemic disease and infections disease spreading and harmful microbial genesis and diffusion.

The invention provides a method for determining the content of six impurity elements of manganese, phosphorus, arsenic, lead, zinc and copper in permanent magnetic ferrite mixed materials. According to the method, a to-be-determined sample is added into concentrated hydrochloric acid and concentrated nitric acid and is dissolved at the low temperature, the sample is in a volumetric flask in a constant-volume mode, and the sample, the concentrated hydrochloric acid and the concentrated nitric acid are shaken up for determining. Prepared manganese, phosphorus, arsenic, lead, zinc and copper standard solutions are used for making a manganese, phosphorus, arsenic, lead, zinc and copper spectral line intensity-mass fraction working curve on a plasma atomic emission spectrometer, the curve is used for analyzing the to-be-determined sample, and the content of the manganese, the phosphorus, the arsenic, the lead, the zinc and the copper in the permanent magnetic ferrite mixed materials is obtained. According to the method, operation is convenient and rapid, the analysis cost is low, the determining result has the good stability, reproducibility and accuracy, and the determining requirements for the impurity elements of the manganese, the phosphorus, the arsenic, the lead, the zinc and the copper in the daily permanent magnetic ferrite mixed materials can be met. According to the analysis method, adopted chemical reagents are few, the pollution to the environment is small, the analysis cost is low, the multiple elements can be determined at the same time, the analysis efficiency is improved, and labor intensity of analysis and operation personnel is reduced.

The invention provides an in-situ measurement method for unsaturated hydrodynamic dispersion coefficients of soil with structural differences. The method comprises the following steps: determining structural differences of soil profiles on the basis of soil particle size analysis; enabling water and solutes in soil to enter a redistribution process on the basis of the boundary condition of fixed water head, and determining soil matrix potential and solution concentration profile distribution at different moments by arranging sensors; providing a soil hydrodynamic dispersion coefficient relation equation on the basis of a mass continuity principle in the redistribution process, determining parameters of the soil hydrodynamic dispersion coefficient relation equation with a central difference method according to the soil matrix potential and solution concentration distribution at two adjacent moments, and further determining the unsaturated hydrodynamic dispersion coefficients of the soil with different texture. The method has the advantages of clear physical conception, simple computational formula, easy operation, high measurement precision and direct experimental result, and more importantly, the hydrodynamic dispersion coefficients of the soil with the structural differences can be determined, and the method has originality in the field.

The invention discloses an analysis and detection method of high-molecular-weight polysaccharides, and the coupling technique of liquid chromatography and high-resolution mass spectrometry is used fordetection and analysis. The method comprises the steps of firstly separating a polysaccharide substance to be detected through size exclusion chromatography, and preliminarily fragmenting polysaccharides in an ion source of a mass spectrum in an in-source cracking mode; and transmitting all ions generated in the ion source into a collision pool by adopting an MSALL mass spectrum acquisition method, carrying out high-energy collision induced dissociation cracking to generate a series of characteristic oligosaccharide ion fragments with high abundance, acquiring the characteristic oligosaccharide fragments, and quantitatively detecting the high-molecular-weight polysaccharides according to the characteristic oligosaccharide fragments. According to the method, two ion fragmentation modes ofin-source cracking and cracking in the collision pool of the mass spectrum are combined, so that the characteristic oligosaccharide ion fragments with high abundance can be obtained. The interferenceof endogenous matrixes can be effectively eliminated by adopting high-resolution mass spectrum data. According to the method, parent ions with a specific mass-to-charge ratio do not need to be selected, and the problem that the parent ions are difficult to select due to polydispersity of the high-molecular-weight polysaccharides can be solved.

The invention discloses an ion chromatography detection method for negative ions in a sodium azide solid product or sodium azide mother liquor. The sodium azide solid product or the sodium azide mother liquor is analyzed by the ion chromatography detection, so that sodium azide and negative ions (the negative ions exist in the form of salt) can be fully separated; meanwhile, the species of the negative ions is judged or / and the content of the negative ions is calculated according to a chromatographic peak out result; a used flowing phase is a mixture aqueous solution of sodium carbonate and sodium hydrogen carbonate. The analysis method is accurate and reliable; the operation is simple, convenient and feasible; the analysis method is easy to popularize; the contents of sodium nitrite in the sodium azide solid product and the mother liquor can be detected, the difficulty in separating sodium azide from sodium nitrite is solved, and an extremely good supplementing effect is achieved on the national standard GB / T26754-2011 Industrial Sodium Azide. Furthermore, multiple negative ion components in the sodium azide mother liquor can be detected, and great guiding significance in industrial production of sodium azide is acheived.

The invention provides a spur gear tooth root crack propagation rule analysis method based on finite element simulation. The method comprises the following steps of firstly, establishing a gear simulation model by utilizing ANSYS, then completing load loading, mesh generation, boundary condition setting, stress solving and other work on the basis of the model, importing the model into FRANC3D to obtain data such as an expansion path and direction of a gear tooth root crack, stress intensity factor change in a crack expansion process, crack life prediction and the like, and finally, analyzing afinite element simulation result to obtain a spur gear tooth root crack propagation rule. According to the method, the propagation rule of the spur gear tooth root cracks is researched based on a numerical simulation method, the crack propagation situation is tracked, the distribution rule of crack tip stress intensity factors and a fatigue life prediction curve are obtained, the calculation precision is high, the experiment speed is higher, the efficiency is higher, and convenience is brought to the depth research of gear tooth root crack propagation.

The invention relates to a method for detecting content of phosphorus and iron in a LiFePO4 / C composite material. The method comprises the steps of mixing the LiFePO4 / C composite material with concentrated hydrochloric acid and concentrated nitric acid, heating to enable the LiFePO4 / C composite material to be dissolved, and filtering an insoluble black substance to obtain a LiFePO4 / C composite material to-be-detected solution; drawing a phosphorus standard curve; adding an ascorbic acid solution into the LiFePO4 / C material to-be-detected solution, enabling ferric iron in the solution to be reduced to ferrous iron, adding an ammonium molybdate solution, carrying the color development, measuring the absorbance of the obtained solution at a position of 720nm in a spectrophotometer by utilizing a cuvette, and finding the to-be-detected content of phosphorus (P) on the phosphorus standard curve according to the absorbance; drawing an iron standard curve; adding a hydroxylamine hydrochloride solution, a sodium acetate-acetic acid buffer solution as well as a phenanthroline solution into the LiFePO4 / C composite material to-be-detected solution, carrying out the color development, measuring the absorbance of the solution at the position of 510nm by utilizing the cuvette, and finding the to-be-detected content of iron (Fe) on the iron standard curve according to the absorbance; calculating the content of P and Fe in the LiFePO4 / C material. According to the method, the interactive effect of the P and Fe ions and the color influence caused by different C coating can be eliminated.

The invention relates to a method for discriminating Chinese mitten crabs in different producing areas, which is characterized by comprising the following steps of: fishing for the Chinese mitten crabs in different producing areas and then placing in a refrigerator for preservation; after thawing the crabs, taking the third ambulatory legs at the left sides of crab carapaces for element analysis,and then drying the third ambulatory legs in a drying oven to the constant weights; grinding dry samples by using agate mortars for homogenization, and then placing in the drying oven at room temperature; weighing and placing the dry samples into a digestion pipe, and adding concentrated nitric acid to the digestion pipe for digesting the dry samples; transferring the digested samples into a quantitating bottle, and then determining the volume of the samples by using pure water to obtain a solution to be measured; measuring the concentration values of trace elements in the solution to be measured and calculating the corresponding concentration values in the third ambulatory leg dry samples of the Chinese mitten crabs. The analysis method in the invention has reliability and favorable precision, and can effectively discriminate Chinese mitten crab crowds respectively produced in the Jiangsu Yangcheng Lake, the Yong Lake, the Changdang Lake and the Jiangxi Junshan Lake and establish a specific trace element geographical fingerprint library and a discrimination function equation of the Chinese mitten crabs in various areas.

The invention belongs to the field of devices, and particularly relates to a thermal deformation analysis method for thermodynamic coupling simulation of an automobile lamp reflector. The method includes data processing and extraction in a thermal simulation process; data processing and extraction in dynamic simulation; thermal coupling and solving of extracted data and post processing of a result, wherein the thermal coupling simulation result can reflect thermal deformation of the lamp reflector and evaluate the offset of a cut-off line, and the thermal deformation of the thermodynamic coupling simulation of the automobile lamp reflector is achieved by the united simulation technology. The method has the advantages of applying load and constraint to a finite element mesh model of a lamp,considering the thermal deformation of the lamp mirror and analyzing the offset of the cut-off line, thereby being more reliable and accurate compared with the traditional analysis method.

The object of the present invention is to provide a method for determining vitamin A and vitamin E in animal source food. Specifically, the present invention uses solid-phase extraction and high-performance liquid chromatography to establish an online solid-phase extraction-high-performance liquid chromatography analysis method for simultaneously determining vitamin A and vitamin E in animal-derived foods. In addition, the invention also provides an online solid-phase extraction analysis system for detecting vitamin A and vitamin E.

The invention relates to a method for detecting the content of swainsonine in locoweed endophytic fungi. The method comprises the steps: pre-treating an endophytic fungi hyphae sample to prepare a test solution; using a high performance liquid chromatograph evaporative light-scattering detector to detect the swainsonine in the locoweed endophytic fungi; taking a mixed solution of acetonitrile andammonium acetate buffer solution as a mobile phase, wherein the volume ratio of acetonitrile to ammonium acetate is 0.2-2 to 0.2-2; separating the swainsonine from other materials in the test sample by an HILIC (Hydrophilic Interaction Chromatography) column; and constructing a map by logarithm of swainsonine in different concentrations and logarithm of a corresponding response peak area so as toobtain a standard curve of the swainsonine. According to the method, the swainsonine in the endophytic fungi Undifilum oxytropis can be effectively separated, and the method can be directly applied to the quantitative analysis of the swainsonine. The method is good in separation effect, strong in specificity and high in accuracy, and the analysis method is reliable.

The invention discloses a gas hydrate sampling and analyzing device and a method. The device comprises a hydrate generation kettle, a sampling module, a drive control module, a sample decomposition module, a weighing analysis module and a vacuumizing module, wherein a stirrer is arranged in the hydrate generation kettle; a gas inlet pipe and a liquid inlet pipe are connected to the top part of the hydrate generation kettle; the sampling module is formed by a transparent high pressure resistant resin glass tube, an upper compression piston, a lower compression piston, an upper hydraulic linkage shaft, a lower hydraulic linkage shaft and a sample delivery pipe; the weighing analysis module comprises an electronic analytical balance, a gas chromatograph and relevant connecting pipelines and components; the drive control module comprises a compression piston, a drive linkage shaft, a hydraulic driver, a spiral elevator, a control computer and the like; and the vaccumizing module is formedby a vacuum pump and relevant connecting pipelines and components. Any height space in a reaction kettle can be sampled with any volume, and any phase state of gas phase, solution phase, hydrate slurry phase and hydrate phase in a hydrate reaction system can be sampled and analyzed.

The invention discloses a method for measuring the diffusion coefficient of on-site soil solute migration with flux conservation in the whole process. First, identify the groundwater flow field to determine the main and secondary migration directions of solutes in groundwater in the soil; then, based on the flux conservation of solutes, establish a mathematical model for simulating soil solute movement; determine the field experimental conditions for the mathematical model; Under boundary conditions, non-converted solutes were injected in the form of injection sources, and the radial flow observation method was used to measure the concentration of non-converted solutes in the main and secondary migration directions with time; the relationship between the diffusion coefficient and the average pore flow velocity The relationship diagram and the influence of soil and pore average velocity on the diffusion coefficient are analyzed, and the diffusion coefficient is determined based on the flux conservation of the whole process of the non-transformed solute. The invention establishes a mathematical model, simulates the movement of soil solute, is easy to operate, has high measurement accuracy, is easy to build an experimental model, is easy to realize conditions, has rich and diverse samples, and has intuitive results.

The invention discloses a terahertz absorption peak position extraction method based on a discrete maximum value. A characteristic absorption peak in a terahertz absorption coefficient spectrum plays an important role in the identification research of a peak-containing target object in the spectrum, so that the identification of the characteristic absorption peak and the determination of the characteristic absorption peak position are necessary work in the identification research. According to an adjoint inflection point method, a baseline spectrum and a differential spectrum corresponding to an original terahertz absorption coefficient spectrogram are obtained mainly by searching inflection points and adjoint inflection point pairs existing in a terahertz absorption coefficient spectrum, and then peak position information in the differential spectrum is determined according to a discrete maximum value method, namely, the absorption peak position of the original spectrogram of a substance. According to the method, weak peaks existing in the terahertz absorption coefficient spectrogram of the substance can be searched, information extraction and accurate judgment of the substance are achieved through the characteristic absorption peaks, and therefore the detection efficiency of the terahertz technology on the substance is improved.

The invention discloses a rapid identification method for turmeric traditional Chinese medicines based on combination of an electronic nose and LightGBM. The identification method comprises the following steps of collecting smell fingerprints of turmeric traditional Chinese medicines such as radix curcumae, turmeric, rhizoma wenyujin concisum and curcuma zedoary by using the electronic nose; extracting the maximum response value of each sensor in the smell fingerprint as a characteristic index; constructing a LightGBM classification model based on the maximum response value of the electronic nose, optimizing the number of decision trees, the learning rate, the maximum depth, a first-order regular term coefficient, a second-order regular term coefficient and a loss function of the LightGBM classification model by using a grid search method, and evaluating performance of the model through ten-fold cross validation; and finally, detecting a to-be-detected sample by utilizing the classification model. The method can realize rapid and accurate identification of curcuma traditional Chinese medicines such as radix curcumae, turmeric, curcuma zedoary and zedoary wenyujin concisum, can effectively solve a problem of difficult identification of curcuma traditional Chinese medicines, ensures accuracy of clinical medication, and has good application prospects and popularization values in rapid identification of traditional Chinese medicines.

The invention discloses an automatic detection method for continuous increase of vibration of mechanical equipment. The automatic detection method comprises the following steps of: step 1, performingfeature extraction on vibration signal waveform data acquired at the current moment of equipment vibration monitoring; 2, updating and calculating a vibration reference, comparing a feature value V obtained in the step 1 with the vibration reference, and judging whether the vibration reference is to be updated or not; 3, calculating an increase result of the data collected at the current moment according to the vibration reference value; and 4, judging whether the data acquired at the current moment is continuously increased or not according to a calculation result in the step 3. According tothe method, the equipment vibration reference standard is automatically calculated and updated, then the increase results of the vibration and the reference standard are collected in real time throughcalculation equipment; whether the increase results are larger than the increase results corresponding to the previous continuous growth point or not is judged; and automatic detection of the continuous increase of equipment vibration is achieved.

The invention relates to a detection method for complete separation of mexiletine hydrochloride associated substances. The method comprises the steps that by using high performance liquid chromatography, detection is conducted, wherein according to chromatographic conditions, octadecylsilane bonded silica gel is used as a filler of a chromatographic column, before feeding, a ghost peak capture column is added, a mixed solution of a sodium acetate buffer solution and methyl alcohol serves as a moving phase A in the chromatographic conditions, methyl alcohol serves as a moving phase B, and gradient elution is conducted. The detection method is high in column efficiency, high in sensitivity and high in repeatability, the degree of separation of a main peak from various impurities is high, theoperation is simple, and an effective and reliable analyzing method is provided for determining the mexiletine hydrochloride associated substances.

The invention discloses a detection method of polyhydric alcohol which comprises the following steps: preparing a test sample solution from a test sample by using a diluent, and detecting the test sample solution by using a gas chromatographic method under the chromatographic conditions that a capillary chromatographic column of polyethylene glycol is used as a stationary phase, the temperature of a sample inlet is 200-250 DEG C, the temperature of a detector is 220-350 DEG C, the column temperature is detected according to programmed temperature rise, wherein the specific temperature rise program is as follows: the initial temperature is 110-130 DEG C, the temperature is raised to 220-240 DEG C at the speed of 5-15 DEG C / min, and the temperature is kept for 0-30 min; the polyol is at least one of diethylene glycol, dipropylene glycol and tripropylene glycol. The method is simple to operate, good in separation degree, sensitive and efficient; and diethylene glycol, dipropylene glycol and tripropylene glycol can be detected. The method can be applied to detection of polyhydric alcohols in the ornidazole injection, and a reliable analysis method is provided for quality control analysis of the ornidazole injection.

The invention relates to a method for detecting the content of swainsonine in locoweed endophytic fungi. The method comprises the steps: pre-treating an endophytic fungi hyphae sample to prepare a test solution; using a high performance liquid chromatograph evaporative light-scattering detector to detect the swainsonine in the locoweed endophytic fungi; taking a mixed solution of acetonitrile and ammonium acetate buffer solution as a mobile phase, wherein the volume ratio of acetonitrile to ammonium acetate is 0.2-2 to 0.2-2; separating the swainsonine from other materials in the test sample by an HILIC (Hydrophilic Interaction Chromatography) column; and constructing a map by logarithm of swainsonine in different concentrations and logarithm of a corresponding response peak area so as to obtain a standard curve of the swainsonine. According to the method, the swainsonine in the endophytic fungi Undifilum oxytropis can be effectively separated, and the method can be directly applied to the quantitative analysis of the swainsonine. The method is good in separation effect, strong in specificity and high in accuracy, and the analysis method is reliable.