In absorption spectroscopy, absorption features impressed on the spectrum of a continuum background source are interpreted in terms of conditions in an absorbing foreground medium. If the opacity per ion for a particular transition beginning from some initial state is known, then the areal density (i.e., the path integral of the density along the path of the continuum propagation) of ions in th...

The nutritional factors which affect lead absorption have been studied. Synthetic diets of known composition were compounded to contain 0-075% Pb as PbCl2 labelled with 203Pb. Rats were exposed to lead for periods of 48 hr. The dietary intake was then measured and the absorption of lead determined by means of a whole-body counter. Lead absorption was increased by high fat, low mineral, low prot...