A Hitachi 170–50 (Japan) flame atomic absorption
spectrometer equipped with hollow cathode
lamps was used for the analysis. The instrumental
parameters were adjusted according to the manufacturer’s
recommendations. A Cu hallow cathode
lamp operating at 324.8 nm was used as the radiation
source. The lamp current was set at 10 mA.
The flame composition was a mixture of propanebutane
(gas pressure 9.81 · 105
Pa) and air (gas
pressure 1.47 · 107
Pa).