[en] The method of determination of U in ²³⁵U slag by X-ray-fluorescence (XRF) analysis is developed. U in acidolysis solution and dregs of ²³⁵U slag are determined by thin sample technique and standard added method. The total U in slag is given. The results of XRF are agree well with those obtained from FIA and high performance liquid chromatography (HPLC). The results are compared with two non-destructive assay (NDA) methods, the calibration data are provided to DNA

[en] The new method for thermal neutron flux density measurement by γ spectrometer is described. The neutron flux density corresponding to 411 keV γ-ray of ¹⁵²Eu is obtained according to the 411 keV γ-ray peak area ratio of ¹⁵²Eu and ¹⁹⁸Au irradiated in reference field and the absolute neutron flux density measurement in reference field obtained by gold (Au) foil activation method. The gold foil is irradiated in the unknown neutron field. The 411 keV γ-ray peak area for ¹⁹⁸Au irradiated in unknown field and ¹⁵²Eu irradiated in reference field can be obtained by other γ spectrometer. The absolute neutron flux density in the unknown neutron field can be gotten by the peak area ratio and the neutron flux density obtained corresponding to 411 keV γ-ray of ¹⁵²Eu