| Popis: |
Up to 45 elements at trace levels can be monitored in fossil fuels of different type and origins using instrumental neutron activation analysis. The procedure, utilized on a routine basis, involves a short irradiation (30–60 s) and immediate γ spectroscopy for the evaluation of short-lived isotopes. A longer irradiation (5–10 h) and γ counting at two different decay times (7 and 20 days) improve the determination of intermediate- and long-lived isotopes. The results with NBS 1632 and NBS 1635 coal SRM agree with the certified or reported values, and are used as routine standards. Trace element contents of different coals, fuel oils, and gas oils are reported. |
