OFF-LINE SOLID PHASE SELECTIVE SEPARATION AND PRECONCENTRATION OF Cu, Zn, Pb AND Cd IN DRINKING WATER BY SOLID-PHASE EXTRACTION USING 4-(2-HYDROXYPHENYLAZO)-3-METHYL-1-PHENYL-2-PYRAZOLIN-5-ONE FUNCTIONALIZED AMBERLITE XAD-2

BURHAM, N; ABDEL AZEEM, SM; Mohamed El-Shahat;