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...Differential pulse polarography in direct current the voltage applied to working electrode increases linearly with time is recorded continuously and a polarogram such as that shown previously results shape of plot called linear ramp small pulses are superimposed on figure below height its modulation amplitude each magnitude mv during last ms life mercury drop then mechanically dislodged not measured rather it once before again for polarograph subtracts first from second plots this difference versus potential just resulting nearly derivative scan sampled twice application at late after when charging has decayed instrumentally subtracted plotted against consists peaks which directly proportional concentration corresponding analytes...