SU960613A1 - Ac polarogram registering method - Google Patents

Description

Of course, shaving is related to enapic control of substances and electrochemical research. It can be used in the means of polarographic and volt-amperometric rapid control of the composition of the substance.

There are known methods for registering polograms based on subtracting the measurement results in two potentiostatic polographic cells with the subsequent registration of 11U.

However, these methods do not provide sufficient accuracy and sensitivity. .

The closest to the invention is the method of registering alternating polarograms, which consists in periodically measuring a signal with a frequency of an alternating polarizing voltage by phase detection of a signal proportional to the alternating current of the cell during part of its period 12.

However, the known method does not have high accuracy, since it does not imply correction of the parasitic phase shift of the measured signal.

The goal of izofeteniya is to increase the measurement accuracy by periodically correcting the phase of the measured signal.

The goal is achieved by the fact that, according to the method of registering recurrent current programs, involving the periodic measurement of a signal with the frequency of an alternating polarizing voltage, by phase detection of a signal proportional to

ts to the cell's alternating current during part of its period, measurements are made twice during each period of the alternating polarizing voltage, and in the first half-period it is measured and

Claims (2)

20, the active component of the cell current is recorded, and in the second half period, the amount of phase drift, relative to the reference voltage, is measured, which 3.96 is used to correct the phase of the recorded sigal. The proposed method makes it possible to carry out the correction of the low frequency component of the noise signal, where n is where and is the frequency of the polarizing voltage; (ju is the frequency that limits the frequency range of the correction, which makes it possible to carry out a greater number of measurements without additional calibration of the device. This is because the phase correction is carried out automatically once during the alternating polarizing voltage; drawing diagrams are shown. Figure 1 shows the alternating polarizing voltage. In connection with the presence of a low-frequency component in the noise signal cneierpe, the zero level of the output signal is observed to slowly decrease. The zero level of the output signal in this voltage is the voltage at the output of the measuring device in the absence of the depolarizer electrochemical cell solution while the zero level of the output signal is kept constant in the range of the double layer capacitance from 0.5 µF to 2.0 The microfarad, which allows correction of the drift on the reactive element. Leaving the zero level during the registration of alternating polarograms can be approximated by a direct line (plot 3). In the absence of correction. The low frequency component of the noise signal of the AC field program is measured with an error proportional to the zero level going off during the entire measurement cycle (plot 2). When perio. Voltage corrected with the frequency of the alternating polarity. Error 3 is determined by leaving the zero reading during one period of polarizing voltage (plot 5). P) The program, measured in this case, is depicted in Example 4. The proposed method can be used both in research and in the mass rapid analysis of technological products of enterprises in the mining industry, metallurgy, geology, etc. Using the method in the analytical control allows you to quickly receive. information on the composition and quality of technological products, which in turn makes it possible to optimize the technological process. The invention of the method of registering alternating polarograms, which consists in periodically measuring a signal with a frequency of an alternating polarizing voltage by phase detection of a signal proportional to the alternating current of the cell during a part of its period, so that in order to increase accuracy, measurements are made twice during each period of alternating polarizing voltage, the active component of the cell current being measured in the first half-period and recorded, and in the second half-period iodine measures the amount of phase drift relative to the reference voltage. and use it to correct the phase of the recorded signal. Sources of information taken into account during the examination 1.Bruk B.S. Polographic methods, M., Energie, 1972, p. 22 2. Author's certificate. USSR on application Nb 2846300/25, cl. Goin 27 / GS, 1980.