Temperature titration device

Abstract

The invention relates to an application circuit for measuring minor temperature changes in chemical reactions and eliminating environment temperature and other external influences, in particular to a temperature titration device, and belongs to the technical field of electronic circuits. The temperature titration device comprises a reference titration vessel A and a positive sample titration vessel B, wherein the reference titration vessel A and the positive sample titration vessel B have the same structures; the basic circuit of each of the titration vessels comprises a current limiting resistor R1 which forms a first voltage divider with a first temperature element RT1, and a potentiometer W1 which forms a second voltage divider with a second temperature element RT2; the first voltage divider and the second voltage divider are connected to a subtracter U1 and are in circuit connection with a diverter switch K1, an analog-digital (A / D) converter and a power supply after being amplified. According to the temperature titration device, the reference titration vessel A and the positive sample titration vessel B are in the same environment and affected by same interference factors, in the temperature titration process, a reference for interference cancellation is formed by comparing changes of the reference titration vessel A with that of the positive sample titration vessel B, the basic circuits of the titration vessels are improved and relative operations are carried out, so that a technological base is provided for measurement of minor temperature changes in chemical reactions.

Description

technical field [0001] The invention relates to the technical field of electronic circuits, in particular to an application circuit for measuring small temperature changes in chemical reactions and eliminating ambient temperature and other external influences. Background technique [0002] Temperature titration is a commonly available analysis method, which is a volumetric method that uses the thermal effect of the titration reaction to determine the titer of the sample. Since each chemical reaction is bound to be accompanied by heat of reaction QR, its precision is generally that of the volumetric method. The allowable accuracy of existing standard instruments is 0.2-0.5%, and precision instruments can reach 0.1-0.2%. The advantage of temperature titration is that it has nothing to do with the characteristics of the sample, such as ionic strength or solvent, and does not interfere with the titration reaction; at the same time, it can operate colored solutions, colloidal sol...

AI Technical Summary

Problems solved by technology

However, in the process of temperature titration, limited by the strict requirements of the solution temperature change, it is susceptible to external interference. The change of ambient temperature and the heating of the temperature element will also greatly affect the titration results, such as the liquid transmission in the buret The resulting thermal interference, the stirring in the titration system and the heat of dilution from adding the titrant also interfere

Therefore, if the simple insulation of the container cannot effectively remove the interference

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