... The mobile phase was aceto- nitrile + phosphoric acid M) (60 + 40 by volume) at a flow-rate of 1 ml min-'. 3 RESULTS ... Brit. Crop Protect. Con5 Weeds, 1987, 531-40. ... Zahnow, EW, J. Agric. Food Chem., 30 (1982) 854-7. Bergon, M., Thtse ts sciences, INP, Toulouse, 1979. ...