Description:
<jats:p><jats:bold>The purest niobium</jats:bold> to be obtained so far was produced in a three‐step process from commercial pure niobium and characterized by n‐activation analysis. In order to measure the Cr, Fe, and Co content, carrier elements were added to the sample after irradiation for 42 d and surface decontamination. After chemical separation, the three elements could be determined by gamma‐ray spectrometry (detection limits 10 ppt, 1.5 ppb, and 4.0 ppt, respectively). Concentration ranges in the five samples: Cr 10—24.7 ppt, Fe 2—6.6 ppb, Co 4—19.0 ppt.</jats:p>