Criteria for Pattern Recognition

50 M sodium acetate buffer, pH 4.85. Potential step increment 4 mV square wave amplitude 25 mV frequency 15 Hz [177] 

Only chrome yellow and chrome orange (lead chromates) exhibit an additional peak at -1-0.45 V, attributable to the reduction of chromate ions  

As can be seen in Fig. 3.4, peak potentials for lead-centered reduction processes are similar, so pigment identification can be improved by considering a series of parameters, as summarized in Table 3.1. 

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