Simultaneous Determination of p-Nitro Chlorobenzene and o-Nitrophenol by Single-Sweeping Oscillopolarography with Cascade Artificial Neural Network

In a 0.3 mol·L-1 KCl medium of pH 6.5,sensitive polarographic peaks of p-nitrochlorobenzene (p-NCB) and o-nitrophenol (o-NP) were observed at -0.71 V and -0.74 V respectively,but the determination of these 2 compounds by the oscillopolarographic method was not possible in the presence of each other due to very close values of their potentials.A new method of adaptive chemical pattern recognition,i.e.,the cascade artificial neural network (CANN) based on the combination of the improved wavelet ANN and BPANN,was proposed and applied to the simultaneous determination of p-NCB and o-NP in a mixture by the single-seeeping oscillopolarography.By optimization of the structure of CANN and adjustment of the parameters,the training speed and prediction accuracy were remarkably improved.In the analysis of 10 simulated samples of mixtures of p-NCB and o-NP,relative deviation and recovery obtained were 3.76% and 96.2% respectively for p-NCB,and were 4.05% and 96.0% respectively for p-NP.