... IUPAC numbers of the PCBs are: 77 (1); 105 (2); 122 (3); 126 (4); 127 (5); 169 (6).6 69* Acta Chemica Scandinavia 44 (1990 ... When working with radiolabelled compounds of high specific ac- tivity, the chemical amounts are often small and separa- tions can therefore be ... Chem. ...