SU1198007A2 - Device for automatic control of titration processes - Google Patents

Abstract

DEVICE. FOR AUTOMATIC REGULATION OF TITLEING PROCESSES by auth.St. No. 1029074, characterized in that, in order to improve the titration accuracy, the device further comprises a time relay and a matching unit, the first and second inputs of the matching unit being connected to the outputs of the comparison units, and the output through the time relay connected to the input of the control unit.

Description

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The invention relates to devices for the automatic regulation of titration processes used in analytical instrumentation and is additional to the main author. No. 1029074.

The purpose of the invention is to improve the accuracy of titration.

FIG. 1 is a schematic diagram of the device; in fig. 2 titration curves.

The device for automatic control of the titration process consists of a titration cell 1, placed between the light source 2 and the receiver 3, the derivative symbol selection block 4, blocks 5 and 6 of the comp. unit, control unit 7, execute. body 9, memory block 9 and voltage level shift elements 10. The selection block 4 is made in the form of an inverter 11 and a switch 12. In addition, the device contains a block 13 of coincidence, the inputs of which are connected to the outputs of blocks 5 and 6 of the comparison, and the output through time relay 14 to the input of the control block 7.

The device works as follows .-

If the titration curve is up. (A), the switch 12 is set to the lower position according to the scheme; if concave (B), the switch 12 is set to the upper position according to the diagram. Thus, the input of the memory block 5 is always supplied with a voltage varying according to the diagram A (Fig. 2). The magnitudes of the shear levels and C and LUj (Fig. 2) of the voltage level shift element 10 are selected from the conditions.

aU;

Ivl,

IVU

ti-t

pulse feeding period

where from control block 7, 3 is the derivative of the titration curve being analyzed. When the device is switched on from the output of the receiver 3, an incremental voltage arises through the derivative selection block 4 to the inputs of blocks 5, and 6 of comparison and memory block 9. By

198007

impulse from block

7 controls, memory block 9 remembers the input voltage U, at time t, and the executive authority

8 feeds the next batch of titrant. The voltage at the output of the receiver 3 continues to vary due to a chemical reaction. If the portion of the titration curve is linear, then the current value of the voltage at the output of receiver 3 exceeds the shift threshold U1 of ftU, and does not reach the level of AU (Fig. 2, Comparison Unit 5 operates, and

Comparison unit 6 does not work. The output signals of blocks 5 and 6 of the comparison go to control block 7. At time t, control block 7 generates another pulse that permits the recording of a new voltage U in memory block 9 and the supply of a new batch of titrant to the titration cell 1. The chemical reaction continues, those. the titration process continues. When the equivalence point is reached, the titration curve undergoes a kink, while there will be no signals at the outputs of blocks 5 and 6 (or if the titration curve undergoes a different type of fracture), i.e. the signals will become the same, while at the output of the control unit - 7 there are no pulses that allow the input voltage to be recorded in memory block 9 and the titrant to be fed by the executive body 8 to the titration cell 1, and

13 matches includes time relay

14and after a predetermined dwell time has expired, the control unit 7 serves as a signal. Turn off the device if due to uneven.

If the outputs on one of the inputs of the block 13 coincide, the turn will turn off and return to the initial state, and the titration will continue. After the signals at the outputs of blocks 5 and 6 compare

will become the same again, time relay 14 will turn on again and so will

continue until the signals at the outputs of blocks 5 and 6 of the comparison become constant for the entire specified period of time, while the time relay 14 finally terminates the titration.

Claims (1)

DEVICE. FOR AUTOMATIC REGULATION OF TITRO-VANIA PROCESSES No. 1029074, characterized in that, in order to improve the accuracy of titration, the device further comprises a time relay and a matching unit, while the first and second inputs of the matching unit are connected to the outputs of the comparison units, and the output through the time relay is connected to the input of the control unit. FIG. 1 1 1198007