461 results about "Standard solution" patented technology

The invention relates to the technical field of total phosphorus detection, in particular to a method for determining total phosphorus in water, which comprises the following steps: 1) digestion treatment: adding an oxidant into a water sample to be detected, and then performing microwave digestion treatment to obtain digested water; a molybdate reagent is added into the digested water, then an improved ascorbic acid solution is added, a chromogenic reaction is completed at the set temperature, and the improved ascorbic acid solution is obtained by mixing an ascorbic acid solution and sodium ethylene diamine tetracetate; measuring the concentration: measuring the absorbance value of the obtained color development product by using a spectrophotometer and a long-optical-path cuvette; and drawing a standard curve: using a phosphorus standard solution as a quality control sample, adding a plurality of calibration points in a low-concentration interval of 0.0-0.1 mg / L, carrying out colorimetric determination, and establishing quadratic equation fitting according to absorbance and concentration so as to determine the total phosphorus content of the water sample to be detected, and the method has the advantages of high sensitivity and good accuracy in total phosphorus testing.

The invention discloses a liquid chromatography determination method for a mixed solution of glyoxylic acid, glycollic acid and oxalic acid and application. The method comprises the following steps: (1) preparing standard solutions with different concentrations; (2) detecting the standard solutions with different concentrations by using high performance liquid chromatography; (3) establishing a linear regression equation of each acid according to the relationship between the concentration of the standard solution and the corresponding peak area; (4) pre-treating a sample to be detected, detecting under the same condition as that in the step (2) by using high performance liquid chromatography, and recording the peak area of each acid in the sample to be detected; and (5) substituting the peak area of each acid in the to-be-detected sample into the corresponding linear regression equation, and calculating to obtain the concentrations of glyoxylic acid, glycollic acid and oxalic acid in the to-be-detected sample. The method is a liquid chromatographic determination method which is simple and convenient to operate, excellent in separation effect, mild in chromatographic condition and compatible with various detectors, can accurately quantify three strong-polarity mixed acids of glyoxylic acid, glycollic acid and oxalic acid, and has important practical application value.

The invention provides a method for measuring silver content in boron-containing water, which comprises the following steps: preparing a blank standard solution and a standard working solution by using a first-stage diluent and a second-stage diluent, and respectively pretreating the blank standard solution, the standard working solution and a to-be-measured sample solution by using a third-stage diluent; the first-stage diluent comprises a nitric acid solution, the second-stage diluent comprises a boron solution, and the third-stage diluent comprises a nitric acid solution; and measuring the silver content of the to-be-measured sample solution by adopting inductively coupled plasma emission spectrometry. According to the determination method provided by the invention, the silver content in the boron-containing water of the nuclear power plant can be accurately and rapidly detected through pretreatment of the test solution, the problem of boron interference in the boron-containing water is solved, the detection accuracy of the silver content is improved, and support is provided for chemical control of nuclear power loop water.

The invention discloses a method for determining the content of hydrogen ions in a chloroplatinic acid solution, and belongs to the technical field of analytical testing. In order to solve the problems that the chloroplatinic acid solution is yellow after being diluted and the manual titration end point is difficult to judge, a potentiometric titration method is adopted, and the end point is determined by measuring electrode potential mutation without depending on indicator color change. The method comprises the steps of test condition preparation, burette calibration, standard solution preparation and calibration, sample treatment and titration, result calculation and the like, a full-automatic potentiometric titrator is selected, the titration volume is controlled within the range of 10-15 mL, and a sodium hydroxide standard solution is used for sample titration after calibration. The relative standard deviation of the determination result is less than 0.5%, the adding standard recovery rate is between 96.3% and 103.1%, and the method has the characteristics of high analysis speed, high accuracy and good stability, is suitable for accurate detection of hydrogen ions in chloroplatinic acid production and quality inspection, and effectively solves the defects of the traditional method.

The invention discloses a method for detecting trace chromium element in copper foil based on ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometer), which comprises the following steps: soaking a lithium battery copper foil in a mixed solution of concentrated nitric acid and hydrofluoric acid for high-temperature digestion, adding a scandium internal standard solution, and fixing the volume to obtain a solution to be detected; preparing a mixed standard solution of chromium element and scandium element with a plurality of concentration gradients, and establishing a standard curve through ICP-OES; and determining the content of the chromium element in the to-be-detected solution according to the standard curve. The lithium battery copper foil is digested through a mixed acid system, concentrated nitric acid provides an acid environment and an oxidation effect, hydrofluoric acid promotes dissolution, it is ensured that the copper foil is completely dissolved, and the digestion efficiency is improved; a scandium internal standard method is introduced, a dynamic background correction mode of ICP-OES is adopted, a scandium internal standard element can correct signal fluctuation in a sample introduction process, dual guarantee is formed by the scandium internal standard element and dynamic background correction, interference of a copper matrix on a Cr spectral line is specifically eliminated, and the trace chromium element detection precision is remarkably improved.

The invention relates to a method for determining potassium by using a nano-enzyme-based colorimetric probe, and the probe and application thereof. The invention relates to a method for determining potassium by using a nano-enzyme-based colorimetric probe, which comprises the following steps of: synthesizing copper and cerium-containing phosphotungstic acid nano-enzyme by using phosphotungstic acid, cerous nitrate and copper chloride as precursors through a hydrothermal method, detecting the absorbance of K < + > standard solutions with different concentrations by using the copper and cerium-containing phosphotungstic acid nano-enzyme as a probe, establishing a quantitative relation between the absorbance and the K < + > concentration, drawing a standard curve, obtaining a regression equation, and determining the potassium content by using the regression equation. And detecting the absorbance of the sample determination standard solutions with different concentrations, and obtaining the K < + > content of the sample through the regression equation. According to the method, the nano-enzyme (Cu, Ce-PWs) is prepared by using tungsten-molybdenum heteropoly acid with high negative charges, unique chelating properties and various structures and Ce < 4 + > and Cu < 2 + > as raw materials, strong mimic enzyme laccase activity is generated through the synergistic effect of Ce atoms and Cu atoms, and the activity of the mimic enzyme laccase is further improved in the presence of H2O2.

The invention relates to the field of test and analysis of impurity element content of primary magnesium ingots, in particular to a method for testing impurity element content of primary magnesium ingots by ICP (inductively coupled plasma) spectrometry, which comprises the following steps: firstly adding H2O2 into a magnesium ingot sample to infiltrate the sample, then adding HCl at an interval of less than 1 minute to carry out first reaction, carrying out first heating after the reaction is finished, and then carrying out second heating, cooling to 20-30 DEG C, transferring to a volumetric flask, and fixing the volume by using third-level water to obtain a sample solution; establishing a working curve by using an ICP spectrometer and a standard solution; testing the sample solution; the ratio of the mass of the magnesium ingot sample to the volume of H2O2 to the volume of HCl is 1: (3-10): (30-54), the method fills the standard vacancy of ICP spectrometry analysis of the silicon element in the primary magnesium ingot, a reliable basis is provided for chemical component analysis of the primary magnesium ingot, the test result is surface, and the method for testing the mass fraction of the impurity elements in the primary magnesium ingot provided by the invention has the advantages of high analysis precision, simple operation, high accuracy and high reliability. The analysis period is short, and related chemical varieties are few.

The invention belongs to the technical field of iron ion detection, and particularly relates to a rapid detection method for ferric ions in water, which comprises the following steps: a fluorescent probe preparation step: taking trihydrate of copper nitrate and tryptamine, adding into a centrifuge tube in sequence, adding ultrapure water, performing ultrasonic dissolution, transferring into a high-pressure reaction kettle, and performing hydrothermal reaction to obtain a fluorescent probe; cooling to room temperature, centrifuging the obtained yellow green solution in a centrifugal machine, and filtering the supernate through a microfiltration membrane to obtain a copper-doped carbon quantum dot CuCDs stock solution, namely the fluorescent probe; analyzing and determining Fe < 3 + >: taking the diluent of the prepared CuCDs solution, adding the diluent into a centrifugal tube containing a Fe < 3 + > standard solution, uniformly mixing, carrying out fluorescent quantitative analysis and detection, and exploring the change rule of the fluorescence intensity ratio of CuCDs; according to the rapid detection method for Fe < 3 + > provided by the invention, the synthesized CuCDs have high sensitivity, can realize on-site rapid detection of Fe < 3 + > in a water medium, and shows a wide application prospect in the field of environmental monitoring.

The invention discloses a detection method for rapidly determining the main content of magnesium hydroxide and calcium oxide in the process of preparing high-purity magnesium hydroxide from salt lake bischofite, which comprises the following steps: determining the main content of magnesium hydroxide: weighing a proper amount of sample, dissolving with hydrochloric acid and fixing the volume to obtain a test solution; taking a proper amount of the test solution, adding triethanolamine to mask interfering ions, adjusting the pH value with an ammonia-ammonium chloride buffer solution, taking chrome black T as an indicator, and titrating the main content of magnesium hydroxide with an EDTA standard solution; and measuring the content of calcium in magnesium hydroxide: taking a proper amount of the test solution, adding triethanolamine to mask interfering ions, adjusting the pH value by using a sodium hydroxide solution, adding a proper amount of a calcium indicator, and titrating the content of magnesium calcium hydroxide by using an EDTA standard solution. The method is simple and easy to implement, can quickly and accurately analyze and detect the main content and the calcium oxide content in the magnesium hydroxide, can realize complete dissolution of the magnesium hydroxide, and does not artificially introduce a large number of impurity elements, so that the system error is reduced, and the detection quality is improved.

The invention relates to the field of water quality monitoring of a secondary loop of a nuclear power plant, in particular to a synchronous detection system and method for ammonia and hydrazine. The method comprises the following steps: removing impurities in a sample by utilizing filtration and reverse chromatography; the sample is quantified to 240-260 [mu] L; carrying out gradient elution on the sample by using a methanesulfonic acid solution as an eluent; wherein in the first stage, the concentration of a methanesulfonic acid solution is controlled to be 13-18 mmol / L, and a sample is washed; in the second stage, the concentration of the methanesulfonic acid solution is controlled to be 55-70 mmol / L, and the sample is Drawing a low-concentration curve based on the 10-500 [mu] g / L standard solution, and drawing a high-concentration curve based on the 500-3000 [mu] g / L standard solution; and measuring the ionic conductivity values of NH4 < + > and N2H5 < + >, automatically selecting a corresponding concentration curve according to the peak area of the ionic conductivity values, and calculating the concentration of ammonia and hydrazine. According to the invention, the synchronous detection of ammonia and hydrazine concentration is realized, the analysis process is simplified, the use of toxic and harmful substance phenol and the generation of toxic and harmful waste liquid of yellow azo compound are solved, the measurement accuracy is improved, and the relative measurement error can be controlled within + / -2.0%.

The invention discloses a method for measuring the content of calcium fluoride in dolomite-containing fluorite mine. The method comprises an acetic acid solution, a hydrochloric acid solution, a triethanolamine solution, a potassium hydroxide solution and boric acid. The method for measuring the content of calcium fluoride in the dolomite-containing fluorite mine comprises the following steps: S1, reagent proportioning; s2, preparing a calcium standard solution; s3, preparing an EDTA standard titration solution; s4, selecting an instrument; s5, preparing a sample; s6, step analysis; s7, content correction and determination; and S8, calculating a result. The invention belongs to the technical field of calcium fluoride content determination, and particularly relates to a method for measuring the content of calcium fluoride in dolomite-containing fluorite mine, compared with the prior art, the method solves the problem of dolomite dissolution when calcium carbonate is leached by acetic acid, and the content of calcium fluoride in the fluorite mine can be measured by accurately calculating the dissolution amount of dolomite. The measured calcium fluoride content is clearer, more reasonable and more reliable and approaches to a true value, and the process operation is simple and rapid, and is suitable for the requirements in the fields of mine production, assay detection and the like.

The invention discloses an analysis method for simultaneously determining residues of telolenol, pentnitrophenol, pentachlorophenol and poisonous phenol in grease. The method comprises the following specific steps: (1) dissolving a grease sample with dichloromethane, carrying out vortex uniform mixing and centrifugation with a sodium hydroxide solution, and taking supernatant; (2) adding formic acid, anhydrous magnesium sulfate, sodium chloride and acetonitrile into the supernatant, carrying out vortex centrifugation, taking the supernatant, freezing and filtering; (3) adding anhydrous magnesium sulfate, a 2% triethylamine solution, multi-walled carbon nanotubes and C18 powder into the filtrate for purification, and filtering after centrifugation to obtain a to-be-detected solution; (4) preparing a matrix blank solution from the negative blank grease through the same pretreatment, and preparing a standard solution with gradient concentration of 1-20ng / mL; and (5) performing quantitative analysis by adopting a matrix standard curve external standard method through an LC-MS / MS detection system. The method has the advantages of economy, simplicity, convenience, high accuracy and high sensitivity, is easy to popularize and use, and can meet the high-throughput detection requirement of phenolic pesticide residues in a complex grease matrix.

The invention relates to the field of chemical testing, in particular to a method for measuring the purity of an acrylonitrile raw material, which comprises the following steps: preparing and calibrating a standard solution, weighing a sample, transferring the sample, carrying out sample titration analysis, carrying out blank titration analysis and calculating a result, thereby obtaining the purity of the acrylonitrile raw material. According to the method, the problems of high cost and overlong detection time of instruments required for detecting the purity of acrylonitrile by a gas chromatographic method are solved, the volatilization loss caused by sample transferring is avoided, the detection efficiency and the test accuracy are improved, and the real purity value of acrylonitrile can be reflected more accurately.

The invention discloses a method for accurately measuring trace calcium in high-purity magnesium metal by combining membrane desolvation and triple quadrupole mass spectrometry, which comprises the following steps: (1) sequentially adding water to wet a high-purity magnesium sample and adding acid to dissolve the sample to obtain a digestion solution, and adding an internal standard solution into the digestion solution; (2) preparing calcium element solutions with multiple concentration gradients, adding the internal standard solution, fixing the volume, and shaking uniformly; (3) sequentially carrying out atomization treatment and membrane desolvation treatment on the prepared solution to respectively obtain dry aerosol of the to-be-detected solution and the standard solution; and (4) carrying out scanning determination on the dry aerosol of the solution to be detected and the standard solution in the step (3) by using a triple quadrupole mass spectrometer, and calculating to obtain the calcium content in the high-purity magnesium sample. According to the method, the 24Mg16O polyatomic interference brought by the matrix element and the mass spectrum interference of the working gas Ar on the to-be-detected element 40Ca are removed through membrane desolvation and triple quadrupole mass spectrometry, so that the trace calcium element in the high-purity magnesium sample can be accurately determined, and the lower determination limit can reach ppb level.

The invention provides a method for measuring the total alkalinity of pore water in salt lake water or marine sediments, aiming at the characteristics of huge alkalinity variation range of a salt lake sample and small sample amount of the pore water in the sediments, the traditional step-by-step dilution alkalinity measuring method is complicated to operate, and simple dilution of the sample can change the balance of a water body carbonate system. The accuracy of total alkalinity determination is influenced, and the uncertainty is large. The method for measuring the total alkalinity of the salt lake water with the high total alkalinity range and the marine sediment pore water with the low sample amount can be used for batch measurement of the total alkalinity of the samples, repeated dilution is not needed, one-time rapid measurement is achieved, the sample measurement accuracy is improved, and manpower and material resources are saved. In the method, the alkalinity of the prepared NaOH standard solution is calibrated more accurately based on the standard curve adding method, the effective measurement range can be expanded by adjusting the concentration of the prepared NaOH standard solution, and the method is wide in applicability.

The invention relates to the technical field of Baijiu detection, and particularly provides a method for detecting low-molecular aldehyde substances in Baijiu. The detection method comprises the following steps: adding an isotope internal standard substance into a white spirit sample, carrying out water bath derivatization, adding sodium chloride into a sample solution to saturate the solution, adding an extracting agent in proportion, carrying out ultrasonic centrifugation, and dehydrating with anhydrous Na2SO4 to obtain a sample solution. The method comprises the following steps: preparing an aldehyde compound mixed standard solution by adopting a simulated matrix, and treating according to a white spirit sample pretreatment method to obtain a standard solution; and simultaneously injecting the sample solution and the standard solution into a gas chromatograph-mass spectrometer, and determining the mass concentration of each aldehyde compound in the sample solution by adopting an internal standard curve method. According to the method, various aldehyde compounds in the white spirit can be detected at the same time, detection errors caused by the difference between a standard solution and a sample matrix are eliminated, the detection limit of the method is 0.47 microgram / L-6. 10 microgram / L, and the method has the advantages of being high in specificity, low in detection limit, high in accuracy and stable in result.

The invention belongs to the technical field of metal content analysis, and particularly relates to a method for simultaneously determining the content of trace cadmium and mercury in nuclear stainless steel. The method comprises the following specific steps: S1, sample treatment; s2, optimizing working parameters of the inductively coupled plasma mass spectrometry analyzer; s3, selecting a Cd measurement isotope; s4, drawing a calibration curve; the method comprises the following steps: (1) preparing a calibration curve by matching main matrixes of iron, chromium and nickel; (2) respectively adding 50 mL of water into 7 100 mL volumetric flasks, respectively adding an iron matrix solution, a chromium matrix solution, a nickel matrix solution, dilute aqua regia, a cadmium standard solution and a mercury standard solution, and diluting with ultrapure water to a scale to obtain a calibration series solution; (3) subtracting the intensity ratio in the zero standard solution from the intensity ratio of the measured element in each standard solution to obtain a net intensity ratio, and drawing a calibration curve by taking the concentration of the calibration solution as an abscissa and the net intensity ratio as an ordinate; and S5, sample determination. According to the method, the content of trace cadmium and mercury in the nuclear power stainless steel can be accurately measured at the same time.

The invention relates to the technical field of environmental analytical chemistry, and discloses a thymol phenolphthalein-TBPE double indicator-based cyanide titration detection method and system, and the method comprises the following steps: adjusting a water sample to be detected to an alkaline pH interval to construct a detection matrix; the method comprises the following steps: introducing a double-indicator system composed of thymol phenolphthalein and tetrabromo phenolphthalein ethyl ester according to a specific ratio into a detection matrix, and constructing a spectrum background for masking yellow interference of sulfide by utilizing the blue color development characteristic of thymol phenolphthalein; dropwise adding a silver nitrate standard solution into the mixed system to execute a complex reaction; according to the method, a spectrum background shielding field is constructed, chromaticity response of a system in a specific wave band is monitored in real time, and when a chromaticity mutation signal from green to bluish violet is captured, a titration end point is judged, and the cyanide concentration is calculated. High-precision anti-interference detection on cyanide in a complex high-turbidity matrix is realized, and the sensitivity and accuracy of end point recognition are improved.

The invention belongs to the technical field of chemical element analysis, and particularly relates to a method and device for measuring the content of trace boron in metal calcium. The method comprises the following steps: dissolving a to-be-detected sample to obtain to-be-detected liquid; measuring the intensity of emitted light to be measured of the liquid to be measured under a preset analysis wavelength by using an inductively coupled plasma atomic emission spectrometer; determining the content of the boron element in the to-be-detected sample based on a pre-determined standard curve and the to-be-detected emitted light intensity, the standard curve is obtained by fitting emission light intensity of a plurality of calcium-containing matrix boron standard solutions with different boron element contents under the preset analysis wavelength. According to the embodiment of the invention, the calcium matrix does not need to be separated, the inductively coupled plasma atomic emission spectrometer is directly used for determination, and the use of a toxic reagent methanol is avoided, so that the harm of the methanol reagent to a human body and the pollution to the environment are avoided, and the labor intensity of operators is reduced.

The present invention discloses a method for quantitative determination of trace harmful elements in various flotation products of rare polymetallic ores, which includes three parts: sample processing, preparation of complex matrix standard solution and sample testing. Each flotation product is digested with analytically pure concentrated nitric acid; the main mineral species of each product are determined by XRD, and the high-purity standard substances of each main associated mineral are digested with analytically pure concentrated nitric acid, and the content of harmful elements to be monitored is determined by ICP-MS after appropriate dilution; each standard substance digestion solution is diluted to a major element concentration of 1000μg / mL, and used to dilute the harmful element standard stock solution to obtain standard solutions with different concentration gradients; then the process blank and digestion sample are tested using an inductively coupled plasma mass spectrometer using a combination of internal standard method and matrix matching to obtain the content of trace harmful elements to be measured. It effectively overcomes the mass spectrometry and non-mass spectrometry interference problems faced by complex matrix sample testing, is suitable for the analysis and testing of trace element content in complex samples, and has a simple method and is easy to operate.

The invention belongs to the technical field of chemical analysis, and discloses a method for measuring the content of metal impurities in quartz glass, which comprises the following steps: 1) adding ultra-pure hydrofluoric acid into a quartz glass sample, heating to dissolve the surface, ultrasonically cleaning the residual sample, and drying to obtain a pretreated sample; 2) respectively adding ultra-pure hydrofluoric acid into at least two pre-treated samples, heating and digesting, completely digesting the samples until the ultra-pure hydrofluoric acid is evaporated to dryness, and then adding ultra-pure nitric acid to obtain a parallel sample; at the same time, preparing at least two blank samples under the same condition; and 3) preparing a standard solution of the to-be-detected metal element with gradient concentration, determining and drawing a standard curve by adopting an inductively coupled plasma mass spectrometer, then determining a parallel sample and a blank sample, and calculating the content of the metal element in the quartz glass sample. On one hand, the sample is controlled not to be polluted in the sample preparation process, on the other hand, the sample is controlled not to be polluted in the testing process, and finally the real metal impurity content is tested.

The invention provides a method for synchronously detecting eight catecholamines and metabolites thereof based on liquid chromatography-tandem mass spectrometry and application of the method. The detection method comprises the following steps: mixing a plasma or urine sample to be detected with an internal standard and acetonitrile; centrifuging, taking supernate, blowing liquid with nitrogen, and adjusting the pH value; mixing the supernate with a propionic anhydride solution, and carrying out derivatization reaction to obtain a test solution; performing liquid chromatography-tandem mass spectrometry detection on the test solution and the standard solution, separating dopamine, epinephrine, noradrenaline, epinephrine, noradrenaline, 3-methoxytyramine, homovanillic acid and vanillic mandelic acid by liquid chromatography, and determining the concentration of the standard substance as an X axis by using a mass spectrometry isotope internal standard quantification method. The ratio of the peak area of the standard substance to the peak area of the internal standard substance is the Y axis, establishing a standard curve, and calculating the concentrations of catecholamine and the metabolites thereof in the test solution. The method is high in detection efficiency, high in sensitivity and good in equipment compatibility, the detection time is shortened, and the cost can also be saved.

The invention relates to a method for simultaneously detecting fluorine and chlorine contents in lead concentrate by an ion selective electrode method, and belongs to the technical field of new material detection, and the method specifically comprises the following steps: (1) preparing a sample into a to-be-detected solution; (2) preparing a fluorine ion electrode standard solution and a chloride ion electrode standard solution; (3) calibrating a fluorine ion standard solution and a chloride ion standard solution; and (4) sample determination and data processing. According to the combined measurement method provided by the invention, through a layered coverage method, optimization of the ratio of potassium hydroxide to potassium nitrate and gradient temperature rise, on the premise of ensuring data quality, an accurate result is conveniently obtained; compared with a fluorine or chlorine testing method commonly used in the market, the method is short in time consumption, simple in equipment and accurate in data; in addition, the combined detection method provided by the invention breaks through the pH limit of traditional single ion detection, and provides a reliable solution for synchronous determination of fluorine and chlorine in a complex matrix sample.

The invention relates to the technical field of instrument checking, and discloses a power plant chemical instrument checking method and device capable of automatically adjusting the temperature, and the method comprises the following steps: collecting the temperature of a main water sample and a reference water sample, monitoring the mixed water temperature, and starting checking when the temperature difference exceeds a temperature threshold value; setting a gradient temperature check point, and calculating a theoretical conductivity value; controlling the temperature of the main water sample and the reference water sample by adopting a multi-stage flow path; when the water temperature reaches a steady state, sodium standard liquid is injected, and theoretical sodium concentration increment is calculated; converting the potential signal into a sodium concentration measured value by adopting a difference algorithm; constructing a temperature-concentration double-variable high-order response curved surface model; performing back-stepping to obtain simulation concentration, calculating confidence factors, and triggering grading response; according to the method, a temperature-concentration linkage response curved surface model is constructed, all working conditions of temperature and concentration are covered, confidence factors are introduced to quantify calibration reliability, and an adaptive closed-loop compensation mechanism is established for iterative optimization, so that chemical verification of the power plant is realized.

The invention provides a full-automatic online detection method for trace polycyclic aromatic hydrocarbon derivatives (SPAHs) in water, which comprises the following steps: (1) pretreatment: standing a water sample, centrifugally filtering to remove suspended matters, adding a prepared mixed standard solution, and directly loading on a machine; (2) enrichment and separation: adopting a Turbo flow C18-XL on-line solid phase extraction column to realize automatic enrichment and matrix purification of the 15 SPAHs, and combining an ultra-high performance liquid chromatography gradient elution program (methanol-ultrapure water system) to realize efficient enrichment and separation; and (3) detection and analysis: performing Full MS-ddMS2 scanning in an APCI (Amplified Peripheral Component Interconnect) source-Orbitrap high-resolution mass spectrum positive and negative ion switching mode to realize synchronous detection of hydroxyl, nitro and oxygen-containing SPAHs. According to the method, a unified detection system covering six hydroxyl polycyclic aromatic hydrocarbons, six oxygen-containing polycyclic aromatic hydrocarbons and three nitro polycyclic aromatic hydrocarbons is constructed for the first time, the detection limit is as low as 0.02 ng / L, and compared with a traditional GC-MS method, the sensitivity is greatly improved, and the sample pretreatment time is greatly shortened. Compared with the prior art, derivatization treatment is not needed, continuous sample injection is achieved through an online solid-phase extraction column regeneration technology, complex matrix interference is effectively eliminated in cooperation with a dynamic elimination function, and a high-sensitivity and high-throughput analysis method is provided for ecological risk assessment of trace SPAHs in underground water and surface water.

The invention provides a method for detecting the content of glycine and urotropine in glycine wastewater, and belongs to the technical field of analytical chemistry. The method comprises the following steps: firstly, obtaining a standard curve by utilizing a standard solution of glycine and urotropine, and then comparing the consistency of retention time of two main peaks of glycine and urotropine in a standard mixed solution and the retention time of a main peak in a sample to be detected, and substituting into the standard curve to obtain the content of glycine and urotropine in the sample to be detected. According to the method, when a standard mixed solution of glycine and urotropine is prepared, the weight ratio of glycine to urotropine is limited to be 1: 1, mobile phase ultrapure water and chromatographic grade methanol selected during high performance liquid chromatography testing are used as solvents, and during high performance liquid chromatography testing, an isocratic elution mode is adopted for elution, so that the content of glycine and urotropine in the mixed solution is greatly improved. Therefore, the obtained working curve prepared by using the respective chromatographic area and concentration data of glycine and urotropine has good linear correlation, and the test accuracy is further improved.

The invention relates to a device and a method for detecting impurity elements in high-purity antimony, which are applied to the technical field of analysis and detection. The detection device comprises an atomizing chamber, an aerosol sample feeding pipe, a sample injection atomizer, an adsorption tank, a conductive pipe, a recovery tank and a waste liquid pipe, according to the method, a test standard solution, a blank to-be-detected solution and a to-be-detected solution are sequentially injected through an inductively coupled plasma mass spectrometer, detection of impurity elements in high-purity antimony is achieved, and the atomized test standard solution, the blank to-be-detected solution and the to-be-detected solution mixed inert gas do rotational flow motion in an atomizing chamber; large-particle fog drops are closer to the inner wall of the atomizing chamber due to centrifugal force and are attracted by static electricity on the conductive tube, so that the large-particle fog drops are attached to the inner wall of the atomizing chamber and the surface of the conductive tube, the removal effect of the large-particle fog drops is achieved, and small-particle fog drops with high ionization efficiency enter the inductively coupled plasma mass spectrometer conveniently; therefore, the element detection quality of the inductively coupled plasma mass spectrometer is effectively improved.

The invention belongs to the technical field of analysis and detection, and particularly relates to a method for determining cinnamyl glycine in a biological sample based on LC-MS. The method comprises the following steps: mixing the biological sample with an extracting solution, and performing extraction treatment to obtain supernate; evaporating and concentrating, and re-dissolving in an acetonitrile water solution to obtain a solution to be detected; diluting the cinnamyl glycine standard stock solution with a PBS (Phosphate Buffer Solution) to obtain a standard solution with a concentration gradient; mixing the standard substance solution with the extracting solution, performing extraction treatment to obtain a mixed standard solution, and testing the mixed standard solution through LC-MS to obtain a standard curve; and testing the solution to be tested, and obtaining the content of cinnamyl glycine in the solution to be tested according to the standard curve. The method can be used for accurately qualitatively and quantitatively analyzing the cinnamyl glycine in the sample, has the advantages of simplicity in treatment, high flux and reliable result, and is easy to clinically popularize and popularize.

The utility model provides a system for measuring trace hydrogen chloride in hydrogen, the system comprises a drainage module, an absorption module and an analysis module, the drainage module can stably lead out the hydrogen to be detected from a main pipeline, the sampling is accurately controlled, and the accuracy and safety of the sampling are ensured; the absorption module can rapidly absorb hydrogen chloride in hydrogen to form liquid to be detected, the absorption process is stable and reliable, and the accuracy of subsequent analysis is ensured; the analysis module comprises a standard liquid storage unit and an ion chromatography unit, the formed to-be-detected liquid and standard liquid can be accurately analyzed, the ion chromatography unit can accurately measure the concentration of trace hydrogen chloride, and the reliability and accuracy of a detection result are ensured.

The invention provides a method for monitoring the acidity of water on line, which comprises the following steps: adding a water sample and a titration indicator into a titration cell, uniformly mixing, measuring the absorbance A background of the water sample mixed with the titration indicator at the wavelength lambda, and taking the absorbance A background as an absorbance background value; titrating the water sample by using a NaOH standard solution as a titrant, and measuring the absorbance A of the water sample at the wavelength lambda in the titration process; taking the moment when the absorbance A is greater than or equal to the absorbance threshold A in the titration process as a titration end point, and obtaining the titration volume of the NaOH standard solution at the titration end point; obtaining the acidity of the water sample based on the titration volume. The method adopts an acid-base indicator titration method to monitor the water acidity and determines the titration end point in combination with the absorbance change of the indicator in the titration process, not only realizes online monitoring of the water acidity, but also is simple and convenient to operate, does not need high-frequency maintenance, can effectively reduce the use cost, improves the water acidity monitoring precision, and is suitable for popularization and application. And application and popularization are facilitated.