Author/Editor		Dolinšek, F; Štupar, J; Vrščaj, V
Title		Direct determination of cadmium and lead in geological and plant materials by electrothermal atomic absorption spectrometry
Type		članek
Source		Journal of analytical atomic spectrometry
Vol. and No.		Letnik 6
Publication year		1991
Volume		str. 653-60
Language		eng
Abstract		A laboratory-assembled atomic absorption spectrometer and graphite cup atomizer were evaluated for direct anlysis of solid samples. A number of geological (soil and sediment) and botanical reference materials were analysed for lead aqnd cadmium either by direct introduction (0.02-5 mg) or by a slurry technique (5-200 mg). Integrated absorbance was measured, and aqueous standards were used for calibration. An (NH4)2HPO4 chemical modifier was necessary in the analysis of botanical samples. The effect of particle size on the accuracy and precision of analytical results was studied. Atomization of small sample aliquots (20-500 micro g) by direct 'weighing in' sample introduction technique requires grinding (1 micro m) whereas slurry sample introduction is more tolerant to particle size effects.
Descriptors		SPECTROPHOTOMETRY, ATOMIC ABSORPTION CADMIUM LEAD NEBULIZERS AND VAPORIZERS PARTICLE SIZE SOIL PLANTS