8 results about "Titration curve" patented technology

The invention relates to a chemical analysis instrument, and particularly discloses a colorimetric-potentiometric combined automatic titration device based on a single chip microcomputer and application of the colorimetric-potentiometric combined automatic titration device. The device comprises a control module, a potential detection module, a color detection module, a fluid driving module, a signal conversion module and a power supply module. The core of the device is that a single-chip microcomputer is taken as a control center, potential signals of a pH composite electrode and light intensity signals of an AS7341 sensor are synchronously acquired, a real-time dynamic linkage titration curve is generated through double data sources, visualization of potential and color mutation is realized, and faults of a single sensor are effectively identified. According to the device, the end point judgment reliability is improved through double-signal cross validation, complex sample analysis can be dealt with, double-dimensional data are synchronously obtained through single titration, the experiment efficiency is improved, hardware modular design is convenient to expand, and the device is suitable for chemical experiment teaching and scientific research scenes.

The invention provides a method for monitoring the permanganate index of water quality on line. The method comprises the following steps: detecting the permanganate index of a water sample by adopting a titration method, and collecting the titration drop number and the absorbance of the water sample in the titration process; drawing a titration curve based on the titration drop number and the absorbance of the water sample; determining a titration end point based on the titration curve, and thus obtaining the titration drop number; and substituting the titration drop number into a standard function to obtain the permanganate index of the water sample. The method provided by the invention not only realizes on-line monitoring of the permanganate index of the water sample, but also is simple and convenient to operate, does not need frequent maintenance, can effectively reduce the use cost, improves the detection precision of the permanganate index of the water sample, and is beneficial to application and popularization.

The disclosed subject relates to techniques for a titration-based analytical method for measuring the concentration of gold (Au) in an Au-treated solution. Exemplary methods may include the addition of complexing agents and / or pH adjusters to achieve sharp inflection points in the titration curve.

The present application provides a kind of method for automatically controlling ore pulp PH with lime milk of grid residue, belong to the technical field of automatically controlling ore pulp PH with lime milk of grid residue, the present application is calculated by online densimeter and ore pulp temperature sensor effective alkali concentration of lime milk and feedforward correction flow setting value, utilize redundant double pH electrode and kalman filter fusion estimation ore pulp pH value, based on mechanism titration curve model driving gain scheduling controller in different pH work interval automatic switching proportional band parameter, and the cumulative concentration prediction value of ore pulp output by physical constraint digestion kinetics modeling network is fed back to gain scheduling controller correction dosing output, solve the technical problem that lime milk of grid residue delayed release alkali leads to ore pulp pH control system cannot predict potential alkali amount, cause systematic over-alkaline.

To provide a measurement method capable of improving accuracy of concentration of amine and / or carbonic acid in a release agent composition.SOLUTION: There is provided a method for measuring concentration of amine and / or carbonic acid in a release agent composition, wherein the release agent composition releases a resin mask, contains amine, and can contain alkali and / or carbonic acid other than the amine, the method includes titrating the release agent composition with acid, and when a titration curve obtained by the titration has a first inflection point, a second inflection point and a third inflection point at a pH of 10 or less, includes calculating concentration of the amine and / or carbonic acid in the release agent composition, from acid consumption to the first inflection point, the second inflection point and the third inflection point, and concentration of the alkali when it contains alkali other than the amine.SELECTED DRAWING: Figure 1

The invention relates to the technical field of chemical analysis of oil products, and particularly discloses a method for judging an acid value titration end point of electric oil based on a color titration method. The method comprises the following steps: acquiring time-varying data of a solution color depth value in a titration process in real time by virtue of a spectrum color sensor, fitting a color titration curve by virtue of a high-order polynomial, calculating the curvature of the fitted curve point by point, and taking a curvature peak point which appears for the first time and has a curvature value of 0.2-2 as a titration end point. The method overcomes the defects that a traditional indicator titration method is strong in subjectivity, an automatic potentiometric titration method is easy to pollute an electrode and has no potential jump, and the like, avoids adverse effects of colors of different oil samples on the RGB value of the titration end point when the end point is judged by the color RGB value in an existing color titration method, and is objective and accurate in titration end point judgment, excellent in repeatability and high in accuracy. The method is suitable for measuring the acid value of electric oil. The method is easy and convenient to operate, economical, environmentally friendly, efficient, accurate and high in application and popularization value.

The invention relates to a method for on-line detection of a quinidine sulfate column-passing process by potentiometric titration, which comprises the following steps: S1, taking the effluent of the quinidine sulfate column-passing process in different periods, adding an inert solvent, and then adding a diluent as a test liquid; s2, placing the test solution on a potentiometric titrator, titrating with a perchloric acid titration solution to obtain a titration curve, and when the titration curve has a second-stage jump, judging that a titration end point is reached, and stopping titration; s3, calculating the concentration of quinidine sulfate in the effluent according to the volume of the perchloric acid titration solution, and drawing a quinidine sulfate concentration-time curve; according to the method, a propionic acid-propionic anhydride diluent system is adopted, an inert solvent toluene is added, interference of dichloromethane and methanol contained in effluent of a column chromatography process on a potentiometric titration method is eliminated, a titration curve has secondary potential jump by optimizing a solvent ratio, a titration end point is marked by the secondary potential jump, and the titration accuracy is improved. And the detection is more convenient, rapid and accurate.