Measurement of talc in flour by the 14 MeV neutron activation analysis method

The 14 MeV neutron activation analysis method was used to measure talc in flour. The neutron yield of a D-T neutron generator was maintained at 1.32 x 10(7)n.s(-1) to irradiate flour samples for one hour. A 1779 keV characteristic.-ray produced by the Si-28(n,p)Al-28 reaction and 1369 and 2754 keV characteristic.-rays produced by the Mg-24(n,p)Na-24 reaction were measured by a 3-inch NaI(Tl) detector and a 2-inch LaBr3(Ce) detector, respectively. The accuracy and detection limit of the talc content measured by the two detectors with different characteristic.-rays were discussed. The results show that the best scheme for measuring talc content is measuring the 1779 keV gamma-ray with the 3-inch NaI(Tl) detector. The detection limit reaches 0.07%, and the relative error of multiple measurements of the same sample is 2.07%. The relationship among the mass thickness of the sample, the talc content and the characteristic peak area was plotted.