The determination of As making use of the K a net intensity requires subtraction of the overlapping Pb L a peak. As the interfering intensity cannot be measured directly, a calculated value has to be obtained from measurement at the Pb Lp line. A mathematical approach was developed which is based on a typical mean value for the ratio between the Pb L a and Lp net intensities. Three measurements per sample are required and the routine calibration procedure is set up with three standard samples. Measurements are fed into a computer programmed to calculate both As and Pb concentrations. The programme corrects for matrix effects by means of one of the measurements that is taken at a chosen background point.The method was devised for fast routine analysis and can be applied to samples of varied composition with the limitation that the As and Pb emission lines are not subjected to significant enhancement. Samples are prepared by grinding the material to a suitable fineness and then pressing it into a tablet. The attainable accuracy and limit of detection for As depend on the Pb level present in each sample. ~~ ~
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.