109 results about "Standard solution" patented technology

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 discloses a quantitative detection method for a mixture of bis (2-hydroxyethyl) disulfide and mercaptoethanol, and relates to the field of analysis and detection. The testing method comprises the following steps: respectively preparing a bis (2-ethoxyl) disulfide standard solution and a mercaptoethanol standard solution with different concentrations; and quantitatively measuring the standard solution and the detection sample through gas chromatography equipment, optimizing chromatographic conditions, drawing a standard curve according to the detection result of the standard solution, and quantitatively analyzing the detection sample by combining the standard curve and the spectrum of the standard solution. According to the present invention, the gas chromatography conditions are optimized, the phenyl functional group-containing polysiloxane is selected as the filler of the chromatographic column, and the detection temperature and the temperature rising program are controlled so as to ensure the separation and the detector sensitivity, and the split ratio is controlled to avoid the non-linear response and the peak overlapping; the detection accuracy of the bi-component bis (2-ethoxyl) disulfide and mercaptoethanol is high, the chromatographic peak separation degree is good, and the product quality detection requirement can be met.

The application belongs to the technical field of analysis and detection, and discloses a method for continuously detecting pH value, sulfuric acid content and zinc ion content of electroplating liquid or conductive roller cleaning liquid. The method comprises the following steps: 1) selecting the "pH" block in "pH / mV" on the potential titrator, setting the instrument parameters, inserting the electrode into the to-be-detected liquid, and reading the pH value displayed by the potential titrator; 2) selecting the "mV" block in "pH / mV" on the potential titrator, selecting the dynamic pH titration mode, setting the instrument parameters, diluting the to-be-detected liquid after the pH value is detected, inserting the electrode into the diluted to-be-detected liquid, and adopting the sodium hydroxide standard solution titration, and ending the titration after two equivalent points appear; and 3) calculating the pH value, sulfuric acid content and zinc ion content of the to-be-detected liquid through a formula. The application can realize the continuous detection of the three indexes by adopting one instrument and one standard titration solution, is simple, fast and high in accuracy, and can effectively reduce the influence of chemical reagents on the health of workers.

This invention provides a method for the simultaneous and rapid detection of four oxidative stress-related biomarkers and its application. The detection method includes: (S1) pretreatment of samples using a protein precipitation extract to simultaneously extract four target compounds: 8-hydroxydeoxyguanosine, 8-isoprostaglandin F2β, 8-isoprostaglandin F2α, and acetyllysine, and preparing a test solution; the protein precipitation extract is a methanol-acetonitrile-perchloric acid mixed solution containing formic acid, wherein the volume ratio of methanol, acetonitrile, and perchloric acid is (8-10):(8-10):(0.5-1), and the volume concentration of formic acid is 0.1-0.5%; (S2) detection of the test solution and standard solution using liquid chromatography-tandem mass spectrometry, and matrix calibration using an internal standard method; plotting a standard curve with the peak area ratio of the target compound to the internal standard as the ordinate and the concentration as the abscissa; and calculating the concentration of the target compound in the test solution based on the standard curve.

The invention discloses a method for measuring the content of carbonate in an industrial basic nickel carbonate substance. The method comprises the following steps: preparing a standard solution, and drawing a standard curve; weighing an industrial basic nickel carbonate sample and putting the industrial basic nickel carbonate sample into a 10ml small sample cup 1; the reaction device is adjusted, and the content of the sample carbonate in the industrial basic nickel carbonate is calculated according to the drawn standard curve; the device and the method provided by the invention are simple and convenient to operate, accurate in result and good in reproducibility, and can be used for accurately measuring the carbonate content in the industrial basic nickel carbonate sample. The method is suitable for rapid determination of carbonate in industrial basic nickel carbonate, and has good popularization and application values.

The invention relates to a qualitative and quantitative detection method for difluoroethylene carbonate in electrolyte, which comprises the following steps: preparing a plurality of DFEC standard solutions, selecting a chromatographic column, setting test parameters of a gas chromatograph-mass spectrometer, and detecting the prepared DFEC standard solutions. Determining a standard curve, a detection limit and a quantitation limit according to the concentration of the standard solution and the detected peak area, and forming a standard curve equation according to the standard curve; detecting the pretreated to-be-detected electrolyte to obtain the peak area of the to-be-detected electrolyte, and searching according to the standard curve to obtain the concentration of the DFEC in the to-be-detected electrolyte, or calculating according to a standard curve equation to obtain the concentration of the DFEC; according to the method disclosed by the invention, high-sensitivity and high-selectivity detection on trace DFEC in the electrolyte is realized through the synergistic effect of the gas chromatography and the mass spectrum and setting of specific test parameters.

The invention relates to the technical field of air detection, and particularly discloses a method for measuring formaldehyde content in indoor air, which is used for measuring indoor formaldehyde gas by potentiometric titration and comprises the following steps: firstly, preparing a K2Cr2O7 standard solution, a Fe < 2 + > standard solution and a formaldehyde standard solution; secondly, taking a K2Cr2O7 standard solution as an absorption liquid of formaldehyde gas, adding sulfuric acid and distilled water, heating in a water bath, transferring into a gas sampler, and sampling air to obtain a sample collection liquid; and placing the sample collection solution in a water bath kettle, continuously heating, titrating the excess K2Cr2O7 and formaldehyde blank sample by using an automatic potentiometric titrator by using a Fe < 2 + > standard solution as a titrating solution, and calculating the content of formaldehyde in the air. The method disclosed by the invention is simple to operate and accurate in determination, the reaction speed can be increased, the reaction degree can be improved, the lowest detection limit can reach 0.006 mg / m < 3 >, and the method can be used for determining the indoor formaldehyde content. The problems that in the prior art, operation is tedious, the duration time is long, and the detection limit is too high are solved.

The invention relates to a method for rapidly and accurately determining the content of tin in tin bronze by using ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), which comprises the following steps: taking A grams of tin bronze, adding B milliliters of concentrated hydrochloric acid and C milliliters of hydrogen peroxide, and dissolving the tin bronze; after supplementing D milliliters of concentrated hydrochloric acid, adding water to fix the volume to V milliliters to obtain a sample solution with the volume fraction of hydrochloric acid being E%; mixing B milliliters of concentrated hydrochloric acid and C milliliters of hydrogen peroxide, supplementing D milliliters of concentrated hydrochloric acid, and adding water to fix the volume to V milliliters to obtain a blank solution with the volume fraction of hydrochloric acid being E%; measuring the sample solution and the blank solution by using ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), and calculating the mass concentration rho1 of the sample solution and the mass concentration rho0 of the blank solution in combination with a tin standard solution working curve; based on the volume V of the sample solution, the mass A g of the tin bronze, the mass concentration rho1 of the sample solution and the mass concentration rho0 of the blank solution, the mass fraction of tin in the tin bronze is calculated. The method can improve the accuracy of the test result and the test speed.

This invention relates to the field of chemical analysis technology, specifically to an analytical method for the content of 1,1-dibromoformaldehyde oxime. The method includes the following steps: (1) dissolving the standard and the sample to be tested separately in acetonitrile to prepare standard solutions and sample solutions; (2) setting the analytical conditions of the high-performance liquid chromatograph (HPLC), and after the instrument baseline stabilizes, injecting the standard, sample to be tested, sample to be tested, and standard in sequence, calculating the average peak area of ​​1,1-dibromoformaldehyde oxime in the standard solution and sample solution respectively; (3) calculating the mass fraction of 1,1-dibromoformaldehyde oxime in the sample to be tested according to the external standard method formula. The analytical method of this invention has strong specificity, good precision, high reliability, and good repeatability, and is particularly suitable for the content analysis of 1,1-dibromoformaldehyde oxime products and for mid-control analysis during the synthesis reaction process.

The application discloses a method for determining tin and inorganic compounds thereof in workplace air. The method comprises the following steps: firstly, using a microporous filter membrane to sample the workplace air; then, using a disposable PP polypropylene digestion tube, a digestion solution and a graphite digestion instrument to digest the microporous filter membrane after sampling; taking down the cooled microporous filter membrane and quantitatively placing it into a test tube by using a hydrochloric acid solution; adjusting the Ph value by using a sodium hydroxide solution and setting the volume to 25.0 mL; preparing a tin standard solution series and drawing a fluorescence intensity-tin content curve by using an atomic fluorescence spectrometer; analyzing the sample by using the atomic fluorescence spectrometer; the sample fluorescence intensity is proportional to the tin content; and obtaining the corresponding tin content from the fluorescence intensity of the sample according to the drawn fluorescence intensity-tin content curve. The method realizes the analysis and determination of trace, ultratrace tin and inorganic compounds thereof, reduces the instability of blank filter membranes caused by external interference, avoids the phenomenon that the blank filter membrane concentration is opposite to the sample concentration, and improves the determination precision.

This application provides a continuous titration method for the sulfuric acid and ammonium nitrate content of silicon etching solution. The continuous titration method includes the following steps: weigh m grams of silicon etching solution sample into a sample bottle, add phenolphthalein indicator, titrate with a first sodium hydroxide standard solution of concentration C1 until a pink color is achieved, and record the volume consumed V1. Calculate the sulfuric acid content. Add neutral formaldehyde solution to the same solution and let it stand for a first preset time to generate a free acid solution. Continue titrating the free acid solution with a second sodium hydroxide standard solution of concentration C2 until the solution turns pink. Gently heat the solution to a preset temperature and maintain this temperature for a second preset time. If the pink color persists, the titration endpoint is determined, and the volume consumed V2 is recorded. Calculate the ammonium nitrate content. This method achieves continuous titration of two components with a single sample, eliminates mutual interference between components, optimizes the endpoint determination method, and thus achieves a simple operation, high accuracy, low sample consumption, and high detection efficiency.

This application discloses a method for simultaneously detecting the content of 28 perfluorinated and polyfluoroalkyl substances in soil, relating to the field of organic matter detection technology. Its main purpose is to address the problem of poor PFAS extraction efficiency in complex matrices, which prevents the simultaneous and accurate detection of multiple target pollutants. The method includes: pretreatment of the soil sample to obtain a test solution; detection of the test solution using liquid chromatography-tandem mass spectrometry to obtain a sample chromatogram; and content analysis of the sample chromatogram based on a standard working curve for 28 perfluorinated and polyfluoroalkyl substances to obtain the substance content results. The standard working curve is plotted based on a mixed standard solution containing 28 perfluorinated and polyfluoroalkyl substances and an isotope internal standard solution.

The invention relates to a quantitative analysis method for determining trace dimethyl sulfide impurities in a dimethyl disulfide product, a high performance liquid chromatograph-variable wavelength detector is adopted for analysis, and the specific analysis method comprises the following steps: preparing a standard solution and a sample to be detected; and detecting the components of the sample to be detected by adopting a liquid chromatography system-variable wavelength detector (VWD). Wherein the detection conditions are as follows: a C18 chromatographic column, a quaternary pump and an automatic sampling system are adopted, a mobile phase A is ultrapure water, a mobile phase B is acetonitrile, the flow velocity is 0.8-1.2 mL / min, and the column temperature is 30-40 DEG C. According to the present invention, the strong ultraviolet response of DMDS is inhibited by using the high water phase environment, and the retention behavior and the peak shape of DMS are improved by using the solvation effect of the synergist so as to achieve the efficient separation of the main component and the trace impurity; in actual sample determination, the method successfully detects the residual trace DMS in the industrial grade disulfide, the result is stable and reliable, and the method is suitable for product quality control and process optimization.

The invention provides an MICP-based sandy soil reinforcement stability evaluation method, device, equipment and medium, and relates to the technical field of soil reinforcement, and the method comprises the following steps: respectively adding an ammonium standard solution into sodium modified zeolite and alkalization modified fly ash to determine the ammonia nitrogen removal rate, and screening candidate mass ratios; on the basis of the candidate mass ratio, the sodium modified zeolite and the alkalized modified fly ash are doped into the standard sand columns correspondingly, the bacterial liquid and the cementing liquid are injected for an MICP reaction, and a solidified sand column is obtained; the dry density and the calcium carbonate generation amount of the multiple solidified sand columns are measured, an unconfined compressive strength experiment is conducted, and an unconfined compressive strength value is obtained; the distribution form of calcium carbonate crystals is observed through a scanning electron microscope for the multiple solidified sand columns, and gelling substances are analyzed through X-ray diffraction; and judging an unconfined compressive strength value based on a microscopic analysis result, and when the unconfined compressive strength value meets a sandy soil solidification threshold value, outputting a solidification grade and a sandy soil strength value to finish stability evaluation. The problem that sandy soil reinforcement is not stable is solved.

The invention provides a near-oil-based drilling fluid base fluid content detection method, which comprises: S1, preparing standard solutions with different near-oil-based base fluid contents, respectively diluting, titrating with a standard hydrochloric acid solution until the pH value tested by a pH meter is 2.95-3.05, recording the consumption volume, calculating the amine value according to a first formula, and forming a standard curve chart of different base fluid contents; s2, testing the initial pH value of the near-oil-based drilling fluid sample by using a pH meter, titrating to the pH value of 3.00-3.20 by using a standard hydrochloric acid solution, and titrating to the initial pH value by using a standard sodium hydroxide solution to obtain a first solution; and S3, titrating the first solution with a standard hydrochloric acid solution until the pH value is 2.95-3.05, recording the consumption volume, calculating the amine value according to a second formula, and comparing the standard curve chart to obtain the base fluid content of the near-oil-based drilling fluid. The method is convenient for field application, and can quantitatively and accurately analyze the content of the base fluid in the field near-oil-based drilling fluid.

The invention relates to the field of substance purity analysis methods, and discloses a method for analyzing the purity of o-phthalic anhydride by using gas chromatography, which comprises the following steps: firstly, preparing a standard solution of which the concentration of each component is close to that of each component in crude phthalic anhydride to be analyzed, and analyzing the standard solution for more than three times; calculating a correction factor of each substance after the peak area repeatability error of each substance is less than 3%; and inputting the correction factor into a method-component table, comparing the spectrogram of the to-be-detected sample solution with the spectrogram of the standard substance solution, determining peak localization of corresponding substances in the to-be-detected sample solution according to retention time, and calculating the purity of phthalic anhydride in the to-be-detected sample by adopting an area correction normalization method. The method is simple to operate, short in analysis time and good in stability and reproducibility.

This invention discloses a method for determining the chemical composition of calcium carbide slag. The method first removes the moisture by ashing the calcium carbide slag, then digests it with concentrated nitric acid and hydrofluoric acid, followed by digestion with saturated boric acid. Finally, based on a standard solution, the concentration of each component is obtained by comparing the test solution and the blank solution, and then converted into the content of oxides. The experimental results show that the recovery rate of calcium oxide is over 96%, and the accuracy and precision meet the standard requirements.

The invention relates to the technical field of nuclear material analysis, in particular to a plutonium solution specific activity determination method and application, and the plutonium solution specific activity determination method comprises the following steps: taking a plutonium solution with known specific activity A1 as a standard solution, determining the liquid flash counting rate of the standard solution, and recording the liquid flash counting rate as C1; obtaining a second-order conductance spectrum of the standard solution by using an ultraviolet-visible absorption spectrum method, determining the peak area of a characteristic absorption peak of tetravalent plutonium in the second-order conductance spectrum of the standard solution, and recording the peak area as S1; measuring the liquid flash counting rate of the to-be-measured solution, and recording the liquid flash counting rate as C2; obtaining a second-order conductance spectrum of the to-be-detected solution by using an ultraviolet-visible absorption spectrometry, determining the peak area of a characteristic absorption peak of tetravalent plutonium in the second-order conductance spectrum of the to-be-detected solution, and recording the peak area as S2; and calculating the specific activity A2 of the solution to be detected according to the following formula. According to the method, liquid scintillation counting and ultraviolet-visible spectrophotometry are combined, so that combination of activity response and concentration response is realized, and acquisition of isotope composition of a plutonium solution to be detected and complex sample pretreatment are not needed.

The invention discloses a method for measuring total phosphorus, polyphosphate, orthophosphorus and polymerization rate in an ammonium polyphosphate fertilizer, and belongs to the technical field of fertilizer detection.The method comprises the following steps that S1, an ammonium polyphosphate sample is weighed and recorded as m, the unit is g, and the ammonium polyphosphate sample is dissolved in water; s2, adjusting the pH value of the solution to 7.5-8.0 by using alkali; s3, titrating with a Mg < 2 + > standard solution to an end point; s4, alkali is added into the titrated solution to adjust the pH value to 8.1-8.5, titration is continued with the Mg < 2 + > standard solution, titration is excessive titration, the volume consumed again is recorded as V2, and the unit is mL; s5, filtering the mixed solution obtained after titration in S4, and washing the precipitate with water; s6, drying the precipitate at 110-118 DEG C until the weight is constant, and weighing to obtain the mass of the magnesium ammonium phosphate precipitate; and S7, calculating the content of orthophosphorus, the content of polyphosphate, the content of total phosphorus and the polymerization rate. The method provided by the invention can be used for rapidly detecting polyphosphate (based on phosphorus pentoxide), orthophosphorus (based on phosphorus pentoxide), total phosphorus pentoxide content and polymerization rate in the fertilizer-grade ammonium polyphosphate.

The utility model discloses a device for rapidly detecting the sulfur content of concentrate, which comprises a closed sulfur determination absorber, a knob at the lower end of the closed sulfur determination absorber is connected with an absorption liquid storage bottle, the upper end of the closed sulfur determination absorber is connected with a basic burette, and the basic burette is externally connected with a sodium hydroxide standard liquid storage bottle; a distilled water storage bottle for washing is externally connected to the joint of the closed sulfur determination absorber and the carbon determination furnace; one side of the carbon determination furnace is connected with a second drying tower, the bottom of the second drying tower is connected with a second gas washing bottle, the second gas washing bottle is externally connected with a first drying tower, the bottom of the first drying tower is connected with a first gas washing bottle, the first gas washing bottle is connected with a buffer bottle, and the buffer bottle is externally connected with an air pump. According to the utility model, the open sulfur determination absorber is replaced by the closed sulfur determination absorber, and the washing branch pipe is additionally arranged, so that the application range of a combustion neutralization method is expanded to the determination of sulfur with the content of 0.01-50%, and one set of equipment and one method can meet the requirements of multiple sulfur determination, thereby not only improving the accuracy of an analysis result, but also saving the cost.

The invention discloses a method for determining the tin content in a lead-tin alloy, which belongs to the technical field of chemical analysis and comprises the following steps: dissolving a lead-tin alloy sample in a mixed acid solution of hydrochloric acid, nitric acid and water, and adding sodium chloride to obtain a dissolved sample solution; adding an EDTA standard solution to carry out complexation reaction, and adjusting the pH value by using a buffer solution; after adding a metal ion indicator, titrating with a zinc standard solution until the solution changes color; then adding ammonium fluoride, uniformly shaking and standing to separate out EDTA (Ethylene Diamine Tetraacetic Acid) combined with tin; and finally, titrating with the zinc standard solution again, recording the consumption volume, and calculating the mass fraction of tin according to a formula. The method is used for measuring 25.0%-45.0% of tin content in the lead-tin alloy, does not need a special device, is simple to operate and short in time consumption, can realize stable and accurate detection, and effectively meets the industrial batch quality control requirement.

The application discloses a kind of power plant water vapor system total silicon content test method, comprising the following steps: taking power plant water vapor system water sample, add hydrochloric acid solution, hydrofluoric acid solution, after heating, cooling to room temperature, add boric acid solution;Take different concentrations of silica standard solution, respectively add hydrochloric acid solution, hydrofluoric acid solution, after heating, cooling to room temperature, add boric acid solution;When atomic absorption draws standard curve and determines sample, first add Ca 2+ Matrix modifier, then add standard working solution or sample;Draw standard working curve;Using atomic absorption to analyze and determine the water vapor system water sample to be measured, according to the absorbance of silicon dioxide in the water sample to be measured to determine the concentration of silicon dioxide in the water sample to be measured.When measuring total silicon (in terms of SiO2), the linear regression determination coefficient R 2 It can reach more than 0.999.The method of the application is convenient to operate, high in accuracy, fast in testing and environmentally friendly.

This invention relates to the field of analytical chemistry, and more particularly to an analytical method for determining the hafnium content in nuclear-grade zirconium alloys. The analytical method includes the following steps: Step S2: Dissolving a metallic or oxide hafnium isotope in concentrated hydrochloric acid and concentrated hydrofluoric acid to prepare an isotope diluent stock solution; Step S2: Adding a corresponding hafnium single-element standard solution to the isotope diluent stock solution, determining the isotope ratio R value, and calibrating the concentration of the diluent solution; Adding the calibrated isotope diluent solution to the zirconium alloy, dissolving the zirconium alloy sample in concentrated hydrochloric acid and concentrated hydrofluoric acid to obtain a sample solution to be separated; Performing extraction chromatography on the sample solution to obtain a hafnium-containing test solution; Determining the hafnium content in the hafnium-containing test solution using inductively coupled plasma mass spectrometry. This invention can accurately determine the hafnium content in nuclear-grade zirconium alloys, improving the stability and accuracy of the analytical results.

The invention provides a method for analyzing the content of gadolinium in a gadolinium sample solution. The method comprises the following steps: preparing a gadolinium standard stock solution of a water phase with preset concentration; preparing the gadolinium standard stock solution into a plurality of gadolinium series standard solutions with different concentrations; the method comprises the following steps: under a selected wavelength, respectively carrying out absorbance measurement on a plurality of gadolinium series standard solutions with different concentrations according to a preset measurement duration to obtain a working curve that the absorbance changes along with the concentrations of the gadolinium series standard solutions; under a selected wavelength, according to a preset measurement duration, carrying out absorbance measurement on the blank reference solution and the gadolinium sample solution to be measured to obtain the absorbance of the gadolinium sample solution to be measured; and obtaining the gadolinium content in the gadolinium sample solution to be detected according to the absorbance and the working curve of the gadolinium sample solution to be detected. Under the selected wavelength, the gadolinium content of the gadolinium sample solution with the corresponding concentration is directly and rapidly measured, and the analysis efficiency and accuracy are improved.

The invention provides a method for detecting the content of urea in a water sample by using high performance liquid chromatography. The method comprises the following steps: preparing a urea standard solution; performing filter membrane filtration pretreatment on the to-be-detected water sample; carrying out high performance liquid chromatography analysis according to optimized chromatographic conditions, and calculating the urea content by adopting a standard curve method; wherein the chromatographic conditions are as follows: a C18 type reversed-phase chromatographic column is adopted, a mixed solution of acetonitrile and ultrapure water is adopted as a mobile phase, isocratic elution is performed, and the detection wavelength is 190-200nm. According to the method, the mobile phase and the chromatographic column are improved, the urea content in the water sample is directly and accurately detected, operation is easy and convenient, the detection time is short, good specificity and stability are achieved, the detection limit is lower than 0.6 microgram / L, the recovery rate ranges from 95% to 105%, the relative standard deviation is smaller than 2%, and the method can be effectively applied to detection and analysis of the urea content in various environment water samples.

The invention relates to the field of glass production, in particular to an ICP (inductively coupled plasma)-based carbonate main component and trace element synchronous detection method, which comprises the following steps: S1, sample pretreatment: grinding a sample, and melting and digesting with a lithium tetraborate-lithium metaborate mixed solvent to obtain mother liquor; s2, gradient dilution, wherein the concentration of microelements in the mother liquor is kept at 0.01-1 ppm; 1 ml of mother liquor is taken and diluted by 100-200 times, and sub-liquor is obtained; preparing at least five groups of concentration gradient test curve ranges by using a full-element standard solution; s3, ICP (Inductively Coupled Plasma) detection: detecting main components, adding a Y internal standard solution into a sub-solution, correcting the solution concentration and atomization efficiency fluctuation, selecting a vertical test, and detecting the concentrations of Ca and Mg; and trace element detection: selecting a horizontal test during the test, and detecting the concentrations of Li, Zr and Nb. According to the method, the problem of detection deviation caused by carbonate and silicate residues is avoided, the Y internal standard is added during detection to correct instrument fluctuation, the matrix interference problem of traditional ICP detection is solved, the detection efficiency and precision are improved, the cost is reduced, and the application range is wide.

The application discloses a method for detecting the acidity of a circulating solution of electro-deposited cobalt, which comprises the following steps: removing oxidizing substances in the circulating solution of electro-deposited cobalt by potassium iodide in an acidic medium; reacting the potassium iodide with potassium iodate and acid to generate iodine molecules; titrating with a sodium thiosulfate standard solution until the solution changes from blue or blue-black to the original color of the solution, which is the end point; and calculating the acidity content according to the mass balance. The method can effectively remove the oxidizing substances in the solution to be measured, avoid the interference with the determination of the acidity content, and make the detection result more accurate. The sodium thiosulfate is innovatively applied to the detection of the acidity of the circulating solution of electro-deposited cobalt, and the sodium thiosulfate titration is used to replace the commonly used sodium hydroxide titration method, so that the interference of the original color of the light red solution with the color judgment of the end point of the sodium hydroxide (phenolphthalein as an indicator) is avoided.

The invention relates to the technical field of in-situ leaching solution sulfate radical monitoring, in particular to an in-situ leaching solution sulfate radical monitoring method and an in-situ leaching solution sulfate radical monitoring system. The monitoring method comprises the following steps: adding an acidic barium salt solution into a reaction cup; adding a preset amount of a to-be-determined water sample into the acidic barium salt solution, and fully stirring to obtain a to-be-determined mixed solution; predicting the sulfate radical concentration of the to-be-measured mixed solution through turbidimetry, and obtaining a supplementary sampling amount according to a prediction result; quantitatively supplementing a to-be-measured water sample into the reaction cup according to the supplementary sampling amount, and fully stirring to obtain a to-be-titrated sample; titrating the to-be-titrated sample to an end point by adopting the EDTA standard solution, and determining the sulfate radical concentration of the in-situ leaching solution according to a titration result. The sampling amount of the to-be-measured water sample is automatically adjusted according to the preset concentration range of sulfate radicals, additional new reagents are not needed, repeated analysis is avoided, the monitoring speed is increased, and the labor cost is reduced.

The invention belongs to the technical field of boron detection, and particularly relates to a method for detecting the content of boron in iron ore and application. The method comprises the following steps: adding a mixed acid of nitric acid, hydrochloric acid and hydrofluoric acid into a to-be-detected iron ore sample, and completely decomposing the to-be-detected iron ore sample through microwave digestion to obtain a sample solution; adding calcium salt into the sample solution, adjusting the pH value, enabling fluorine ions in the sample solution to form calcium fluoride precipitates, enabling iron and niobium interference elements in the sample solution to form hydroxide precipitates, and filtering out the calcium fluoride precipitates and the hydroxide precipitates to obtain a filtrate without matrix interference; a standard addition method is adopted, a series of boron standard solutions are added into the filtrate, the spectral line intensity of the series of solutions at the position of 249.678 nm is measured, a working curve is established, and the boron content in the iron ore sample to be measured is calculated through an extrapolation method. The three major pain points of iron and niobium interference, fluorine corrosion and lengthy process are solved in series.

The invention provides a method for measuring iodine in a regional geochemical survey sample, and belongs to the technical field of measuring methods. The iodine content in the sample is determined by adopting a spectrophotometric method. The method comprises the following steps: mixing a sample with an Eschka mixed solvent, heating and melting through a program, extracting in a water bath, and fixing the volume; taking supernate, sequentially adding sodium carbonate, acetic acid, tetraalkali and chloramine T solution for color development, and measuring the absorbance in a cuvette with the wavelength of 600nm and the length of 1cm or 3cm. Drawing a standard curve through an iodine standard solution, and calculating the iodine content of the sample according to the absorbance after the blank is deducted. The method is low in detection limit, high in accuracy and good in precision. The method is easy to operate, low in cost, superior to the existing national standard in efficiency, suitable for analysis and test of large-batch geochemical sample iodine and wide in application prospect.