Narrow Results

The enrichment procedure of heavy metals (Fe³⁺, Co²⁺, and Hg²⁺) in water was examined in conjunction with in-air PIXE. The preconcentration step consisted of adsorption of dibenzyldithiocarbamate complexes of the metal ions onto dibenzylidene-D-sorbitol gels. The colloidal gels in solutions were then collected on a nuclepore membrane for direct irradiation by proton beams in a system of vertical beam type in-air PIXE. The amounts of the chemicals used in the enrichment were minimized to prepare thin target specimens with the homogeneous composition. The metal-recovery in the preconcentration step was confirmed to be quantitative in a wide range of the concentrations. The reproducibility and detection limit were shown and discussed for the present setup of PIXE analysis in our laboratory.