72results about "Chemical analysis using titration" patented technology

The application discloses a kind of Raman determination methods of boric acid and berberine hydrochloride in compound zinc sulfate eye drops, belong to the technical field of drug quality detection, the method determines the total boron content of sample using ion chromatography, determines the borax content of sample using potentiometric titration, boracic acid chemical reference value is obtained according to formula, and the chemical reference value of berberine hydrochloride is determined using high performance liquid chromatography method;Collect series sample Raman spectrum and carry out pretreatment;Using partial least square method, the quantitative model of boric acid and berberine hydrochloride is established respectively;The Raman spectrum of sample to be measured is substituted into the model, and the content of boric acid and berberine hydrochloride is output simultaneously.Compared with the current legal standard determination method, the application overcomes the problem of component interference determination in compound system, has higher specificity and accuracy, realizes the rapid, non-destructive, synchronous detection of two main components, and can be used for online monitoring in production process and daily supervision of drug supervision department.

The application relates to the technical field of agricultural analysis and detection, and discloses a multi-union type fertilizer synergist urease activity automatic detection and analysis system, which comprises a physical execution layer and an intelligent control layer. The physical execution layer is configured with a reaction generation module, a gas transmission and conditioning module and a detection and regeneration module which are connected in sequence in a gas path, is used for constructing a closed loop flow path and executing ammonia gas absorption and titration. The intelligent control layer controls the gas transmission and conditioning module to switch the gas path according to an adaptive time sequence, constructs an intermittent absorption environment, executes static titration and resets trace acid liquid under the condition of maintaining a bypass state, and simultaneously uses system lag parameters to perform dynamic deconvolution reconstruction on discrete titration data collected, so as to restore a continuous reaction rate curve. Through the combination of hardware time sequence control and algorithm correction, the application eliminates the influence of physical transmission delay on the signal phase, and improves the detection precision and efficiency of the dynamic change of urease activity.

This invention proposes an auxiliary device for accurate burette reading, comprising a clamping assembly with a clamping cavity formed within it for holding the burette. The clamping assembly has a first mounting position and a second mounting position, which are opposite to each other and respectively connected to the clamping cavity. An optical component is located at the first mounting position, comprising a magnifying element and a transparent lens. The transparent lens has graduations, and the magnifying element is located between the transparent lens and the clamping cavity. A color contrast element is located at the second mounting position. By clamping the burette in the clamping cavity at its liquid level, the reading at the burette can be magnified through the transparent lens and magnifying lens at the first mounting position. The second mounting position is opposite to the first mounting position, and the color contrast element at the second mounting position acts as a background to enhance color contrast, facilitating accurate burette reading.

The preparation process of the eczema cream comprises the following steps: S1, raw material pretreatment: coarsely crushing calcined calamine; removing impurities from cortex phellodendri, coarsely crushing, and removing impurities from indigo naturalis for later use; mixing the three components, performing superfine grinding, and sieving with a 100-mesh sieve to obtain a medicinal powder raw material; s2, substrate preparation: melting and stirring beeswax and sesame oil at 85-90 DEG C, and cooling to obtain a transparent substrate; s3, mixing and forming: mixing the medicinal powder raw materials and the transparent matrix according to the mass ratio of (2.07-1): 2.13, uniformly stirring at 85-90 DEG C, cooling, solidifying, sterilizing and packaging to obtain the eczema cream. According to the standardized preparation process and the quality inspection method of the eczema cream, by optimizing superfine grinding parameters, a matrix ratio and a quality control system, stable production and quality controllability of the eczema cream are achieved, and technical support is provided for preparation conversion.

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.

The application discloses a testing method for the content of divalent iron ions in EDTA chemical cleaning solution, and aims at the problem that the existing titration method cannot accurately determine the content of divalent iron ions due to the interference of EDTA. Instead of adopting a complex separation step, the method eliminates the interference through two steps. First, the to-be-tested solution is adjusted to be acidic to weaken the complexing capacity of EDTA, and then a sulfur-phosphorus mixed acid solution is added. The strong acidity of sulfuric acid is used to inhibit the complexing reaction and avoid hindering titration. The whole process is based on the principle of titration method, and does not need expensive instruments and reagents, and is low in cost. The operation is simple and does not need professional skills. The application adopts the high-stability potassium dichromate standard solution, reduces the calibration frequency, realizes rapid, convenient, accurate and low-cost determination, and is suitable for on-site detection requirements.

The invention relates to a 4-(methyl nitrosyl amino)-1-(3-pyridyl)-1-butanone (NNK) purity standard substance as well as a preparation method and application thereof. The 4-(methyl nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) purity standard substance is white powder, has the melting point of 63-65 DEG C, the boiling point of 346 DEG C and the density of 1.2 g / cm < 3 >, is hermetically packaged with a brown bottle, and has the purity of 99.38%. The purity standard substance disclosed by the invention is high in purity, accurate and traceable in quantity value, good in uniformity and good in stability.

The utility model discloses a kind of electrochemical titrator stable pedestal, it is related to experimental equipment technical field, including titrator, vertical installation is carried out in titrator column, the titration frame is slidably arranged in column, the sliding frame is also slidably arranged in column, the sliding frame is below titration frame, the clamping assembly for being clamped and fixed in titration container on titrator is arranged on the sliding frame, the clamping assembly includes the positioning ring connected on sliding frame, adjusting bolt is threadedly connected on the positioning ring, adjusting bolt rotates on positioning ring to displace along the radial direction of positioning ring, the end of adjusting bolt extending to the inside of positioning ring is connected with sliding rod, and the one end of sliding rod is connected with abutting head. The utility model clamping assembly can effectively fix titration container, avoid its displacement or pour due to factors such as touch, vibration during titration, improve titration stability and data accuracy.

This utility model relates to the field of chemical analysis technology and discloses an illumination device for chemical analysis, including a base, a column at the top of the base, a mounting frame on the outside of the column, two support plates at both ends of the mounting frame, and titration clamps at the ends of the two support plates. The illumination component includes a storage groove on one side of the mounting frame, a fixing frame at one end of the storage groove, an extension plate on one side of the fixing frame, a sleeve on the inner side of the extension plate, and sliding grooves at both ends of the sleeve, with lamps installed inside the two sliding grooves. Gears are provided on the inner wall of the extension plate, and connecting frames are provided on one side of the two lamps, with racks on the inner wall of the connecting frames. This utility model, by folding and storing the illumination lamp inside the titration rack, can be unfolded in poor lighting conditions to illuminate the scale of the burette, facilitating observation of the titration endpoint color and titration volume in milliliters, ensuring data accuracy.

This invention relates to a purity standard for N-nitrosonornicotinamide (NNN), its preparation method, and its uses. The N-nitrosonornicotinamide (NNN) purity standard of this invention has a yellow, oily appearance and a density of 1.3 ± 0.1 g / cm³. 3 The sample is sealed in brown sample vials and has a purity of 99.35%. The purity standard material of this invention has high purity, accurate and traceable values, good homogeneity, and good stability.

This utility model belongs to the field of chemical reaction apparatus and discloses a distiller for detecting the nitrogen content of milk powder. It includes a housing, an internal structure for the reaction to proceed, four sets of support feet at the bottom, an operation panel on one side, a water inlet and a feed inlet at the top, a discharge inlet on the side of the housing near the operation panel, a cleaning inlet at the bottom, and clearance openings corresponding to a pressure balance tank and a condensate tank on the side of the housing away from the operation panel. The internal structure includes a steam generator, an alkalization distillation device, and a condensation device. This utility model has a compact and reasonable structural design, is electrically controlled, simple and convenient to use, and can prevent boiling over and negative pressure backflow, prevent excessive internal pressure, significantly improve experimental safety, and ensure stable experimental operation.

This invention discloses a rapeseed quality detection method based on feature wavelength optimization and multi-model fusion. The method involves collecting full-band near-infrared diffuse reflectance spectral data of rapeseed samples and simultaneously measuring the true values ​​of physicochemical indicators to construct an original dataset. Based on the data distribution characteristics of each physicochemical indicator, the original dataset is divided into a training set and a test set. Preprocessing algorithms are selected for each physicochemical indicator to process the full-band near-infrared diffuse reflectance spectral data. Dimensionality reduction algorithms are selected for each physicochemical indicator to extract feature wavelengths from the preprocessed spectral data. Predictive models for each physicochemical indicator are established based on the training set, and the performance of the predictive models is verified using the test set to determine the optimal algorithm combination for each physicochemical indicator. The variable importance projection algorithm is used to calculate the comprehensive contribution score of each wavelength point in the full-band spectrum to the four physicochemical indicators. A multi-indicator comprehensive threshold is set, and the core light source wavelength of the portable device is determined from the high-score region.

This invention relates to the field of grain chemical analysis technology, specifically a quality identification method for distinguishing between acutely oxidized corn and aged corn. Addressing the shortcomings of existing technologies that rely solely on single fatty acid values ​​to accurately differentiate the underlying deterioration mechanisms of corn, this method, under the premise that the test samples have similar fatty acid values, performs a multi-level comparison of core lipid oxidation metabolites by measuring free fatty acids, peroxide value, anisidine value, and malondialdehyde concentration in a stepwise manner; and extracts the effective components of the sample to measure free radical scavenging rate, analyzing the limit of damage to endogenous antioxidant capacity in cells. By calculating a unique quantitative comprehensive discrimination index from the above indicators, as well as multi-dimensional data such as sensory characteristics, the reverse scissor difference of macromolecular nutrients, and the specific response differences of targeted antioxidants, this invention overcomes the blind spot of misjudgment due to "same value, different quality," enabling accurate qualitative classification of deteriorated corn and guiding feed processing enterprises in scientific grading.

The utility model provides a kind of titration device for drug research and development, it is related to the field of pharmaceutical processing equipment, it includes: bottom plate, bottom plate top is used to place conical flask;Stand, bottom plate top is equipped with stand, stand one side is equipped with mounting ring, for the clamping fixation of burette;Clamping assembly, clamping assembly is equipped on the inner wall of mounting ring, for the clamping fixation of burette;And mixing assembly, mixing assembly is equipped on the top of bottom plate, for the mixing of conical flask.This kind of device cooperates through the synergistic effect of clamping assembly, realizes the real-time posture fine adjustment and self-adaptive clamping of burette, adjusts motor based on gyroscope feedback data dynamic control mounting ring angle, offset caused by compensating external force disturbance, ensure that burette is always in vertical equilibrium state;The integrated design of mixing assembly in combination with antiskid component improves the mixing efficiency and fixed safety of reaction vessel.

A kind of physical and chemical quality systematic evaluation method of hairy grape refined beer belongs to beer quality detection and evaluation technical field.The present application is to solve the technical problems that the existing traditional beer national standard detection method is poor in adaptability to hairy grape refined beer matrix,there is no exclusive systematic quality evaluation system,there is no precise synchronous detection method for characteristic functional components and flavor substances,constructs a whole-process evaluation system covering four dimensions of fermentation process dynamic monitoring,basic physical and chemical index detection,characteristic functional component quantification and core flavor substance analysis,optimizes the exclusive operation parameters and chromatographic conditions of each detection index.The detection results of the method are accurate and the detection efficiency is high,which can realize the whole-process standardized evaluation of hairy grape refined beer from fermentation control to finished product grading,provides scientific support for process optimization and quality standard formulation of this category.

This invention discloses an analytical method for lithium battery electrolyte, relating to the field of lithium battery electrolyte analysis technology. The method includes steps S1: collecting a lithium battery electrolyte sample under an inert atmosphere and pre-treating the sample to obtain a diluent for testing; Step S2: injecting the diluent into an analytical detection system to obtain characteristic response signals of each component in the lithium battery electrolyte; Step S3: calculating the content of the target component based on a preset quantitative analysis model and the characteristic response signals; Step S4: detecting the free acid content in the electrolyte; Step S5: detecting trace moisture in the electrolyte; and Step S6: data feedback and evaluation. This application can solve the problems of easy degradation of sensitive components in the electrolyte and quantitative deviation caused by solvent evaporation, achieving integrated and accurate analysis of organic and inorganic components. Combined with embedded closed-loop feedback logic, it significantly improves product consistency and data fidelity in the lithium battery electrolyte production process.

The application discloses a method for detecting free acidity in sulfuric acid-based all-vanadium liquid flow battery electrolyte, and relates to the field of liquid flow batteries. The method comprises the following steps: preparing a vanadium ion masking agent with a pH of 6.5-8.0 and a concentration of 1-2 mol / L; adding the vanadium ion masking agent into the electrolyte to be measured, adding standard alkali liquid dropwise, detecting the mass of the system before and after adding the standard alkali liquid, and obtaining the free acidity in the electrolyte to be measured by using a calculation formula of free acidity C. The addition of the vanadium ion masking agent effectively eliminates the influence of interference sources such as vanadium ion hydrolysis and oxidation and reduction on the detection result, and further guarantees the accuracy of the acid-base titration detection result.

The application discloses a kind of full-automatic insulating oil micro water content tester, including instrument body, instrument body is provided with power module, display module and controller.Electrolytic cup, reagent container, pure water container and oil sample container are arranged on the instrument body.Electrolytic cup and pure water container and oil sample container are connected by sample feeder respectively;Electrolytic cup and reagent container are connected by quantitative pump and sealed stainless steel pipeline.Light source and camera are also provided to obtain the image of electrolyte, and the controller obtains the image change data of electrolyte through the camera, and gives the instruction to cut off the electrolysis power supply when the change rate of the image reaches the set limit value.The application can accurately obtain the end point of electrolysis process and improve the accuracy of micro water detection.

The utility model provides a kind of full-automatic water quality chemical oxygen demand analyzer, belong to the technical field of chemical analysis and detection, including fixed rack, digestion unit, liquid adding unit and moving unit, fixed rack includes frame body;Digestion unit includes multiple digestion furnace being arranged in the frame body mesa and the temperature control module corresponding with digestion furnace, temperature control module is used to control the temperature of digestion furnace;Liquid adding unit includes multi-channel switching valve, first liquid adding module, second liquid adding module and power component, second liquid adding module is connected with multi-channel switching valve, and power component is used to provide liquid adding power for first liquid adding module and second liquid adding module;Moving unit includes the mechanical arm connected to frame body and the gripper assembly connected to mechanical arm, gripper assembly includes two oppositely arranged clamping plates and the first pneumatic component connected to be arranged in two clamping plates, and first pneumatic component is used to drive two The clamping plate is mutually close or away from each other.The utility model improves work efficiency.

This invention relates to a mixed solution standard of N-nitrosamines and its preparation method. The standard is composed of N-nitrosonornicotinic acid (NNN) purity standard, 4-(N-methylnitrosamine)-1-(3-pyridyl)-1-butanone (NNK) purity standard, N-nitrosoneonicotinic acid (NAT) purity standard, N-nitrosoacetine (NAB) purity standard, and methanol. The standard of this invention exhibits high purity, accurate and traceable values, good homogeneity, and good stability.

The present application relates to a kind of double bond content testing method of inorganic powder surface chemical bonding and its application, the testing method includes the following steps: inorganic powder sample and solvent are mixed to carry out soxhlet extraction, remove the double bond of surface physical adsorption, then according to iodometric method, the double bond content testing of inorganic powder sample surface chemical bonding is obtained.The detection method provided by the present application can effectively overcome the problem of higher content measured by traditional method by introducing soxhlet extraction operation, and the method has high precision and accuracy, can provide guiding significance for the preparation, quality detection of inorganic powder and its application in resin composition.

The application discloses a kind of glass surface stress detection equipment, it includes stress detection device, feeding device, discharging device and first control module, stress detection device includes detection table, stress detector and refractive liquid titration mechanism;Feeding device is used to move the glass sheet to be detected to the detection station of the detection table;Discharging device is used to remove the glass sheet on the detection table and finish detection;First control module includes first inductor and first controller, and the first inductor and the refractive liquid titration mechanism are electrically connected with the first controller respectively;First control module can control the refractive liquid titration mechanism and the stress detector according to the incoming information of the feeding device, to titrate refractive liquid on the upper surface of the detection table and carry out stress detection to the surface of glass, realize the automation of glass surface stress detection, and can batch glass surface stress detection work.

The application discloses a kind of microfluidic titration device and titration method, it is related to microfluidic analysis detection technical field, including base, white background plate, black background plate, vertical column, horizontal beam, test tube clamp, titration test tube, background light box, background lamp, light shield, base level, adjustable foot, beam horizontal adjusting mechanism and beam micro level, automatic control unit, microfluidic flow control module, titration end point image recognition module, background driving module, data processing storage module;The bottom of base is provided with adjustable foot, base level is arranged on base, vertical column is fixed on base, horizontal beam is connected with vertical column by beam horizontal adjusting mechanism, beam micro level is fixed on horizontal beam, and test tube clamp is arranged on horizontal beam.A kind of microfluidic titration device and titration method, through the double leveling structure of base and beam, add automatic control module to realize intelligent regulation and control of whole process, eliminate benchtop and assembly error, and the batch detection efficiency of multi-channel clamping is improved.

The present application relates to a kind of based on big data's alkali throwing cleaning machine liquid life prediction method and system, it is related to the field of alkali throwing cleaning machine liquid life prediction, wherein based on big data's alkali throwing cleaning machine liquid life prediction method includes: the steps of building multidimensional feature parameter acquisition system, constructing liquid life prediction model, model training verification and self-adapting correction, real-time prediction and failure early warning, generating liquid replacement or supplement suggestion, based on big data's alkali throwing cleaning machine liquid life system includes, acquisition module, data processing module, prediction module, training module, early warning module, feedback module and data storage module: by collecting effective alkali concentration, silicon ion concentration, impurity ion concentration, pH, temperature, viscosity, process condition and other multidimensional feature parameters, not only rely on single pH value or alkali concentration, comprehensively reflect the real attenuation state of liquid, improve prediction accuracy.

This invention belongs to the field of chemical material mixing technology, and particularly relates to a precise mixing system and method for alkyl aluminum chloride. Addressing the problem of large errors in the manual mixing of alkyl aluminum chloride and inert solvent mixtures in existing technologies, which necessitates manual sampling and remixing, affecting efficiency and accuracy, this invention provides a precise mixing system and method for alkyl aluminum chloride using this system. This invention first verifies the fluid quality using a floor scale, then uses dual detection of chloride and aluminum ions to infer the alkyl aluminum chloride content. A PLC control system calculates the error and intelligently controls the replenishment of corresponding components, providing double assurance for the precise mixing of alkyl aluminum chloride at a predetermined concentration. This significantly accelerates sampling and secondary mixing, improving production efficiency.

This invention belongs to the technical field of metal ion adsorption materials, specifically a method for preparing an adsorbent and a method for determining the soluble zinc content of raw materials used in the ammonia chloride process for producing electrolytic zinc. This invention modifies the surface of manganese dioxide with a thiourea-based silane coupling agent, grafting a silane coupling agent containing a thiourea structure onto the surface of manganese dioxide. The adsorption of lead, copper, and cadmium ions in solution is achieved using the manganese dioxide matrix and the thiourea-based silane coupling agent on the matrix surface, while effectively preventing the adsorbent from adsorbing zinc ions from the solution. When the adsorbent prepared by this invention is used to determine the soluble zinc content of raw materials used in the ammonia chloride process for producing electrolytic zinc, it exhibits a small testing error and can effectively improve the accuracy of soluble zinc content determination.