PRECONCENTRATION OF DILUTE-SOLUTIONS AT THE 10-12 G-G LEVEL BY NON-BOILING EVAPORATION WITH VARIABLE VARIANCE CALIBRATION CURVES

A procedure is described for the preconcentration of very dilute solutions at the 10-12 g/g level by nonboiling evaporation in Teflon bulbs in the presence of hydrofluoric and nitric acids under clean room conditions. By processing various synthetic standards, calibration curves are determined by variable variance statistical techniques for Na, Mg, K, Ca, Fe, Al, Mn, Pb, Cd, Cu, Zn, and Ag. The results of the analysis by this procedure of a typical snow sample collected at South Pole Station show that for most of the elements the precision is in the order of 10% (with ±2σ confidence limits). © 1979, American Chemical Society. All rights reserved.