METHOD OF DIFFERENTIAL MEASUREMENT OF VOLT-AMPERE CHARACTERISTICS Russian patent published in 2000 - IPC

FIELD: polarography. SUBSTANCE: method is applicable to devices intended for multielement volt-amperometric analysis and in A C polarographs. Technical objective of invention consists in provision of possibility of simultaneous determination of various substances in multicomponent solution with required accuracy in wide range of mutual relations of concentrations of determined substances or of analytical signals corresponding to these substances. In agreement with invention polarizing voltage including voltage scan and train of symmetrical bipolar pulses with zero time interval between them is applied to electrochemical cell, current of electrochemical cell in time interval less than duration of half-period of pulse is measured by way of isolation and amplification of pulse component of current of electrochemical cell without overloading of amplifier. Gain factor of amplifier is so set prior to each bipolar pulse that it is maximal. In this case output signal of amplifier is in certain range. After algebraic summation of currents caused by positive and negative half-periods of one bipolar pulse obtained sum is divided by gain factor of amplifier specified for measurement. EFFECT: simultaneous determination of various substances in multicomponent solution with required accuracy. 1 cl, 3 dwg