Preparation and Characterization of Neutron Dosimeter Materials

Nitrogen Trifluoride-Based Fluoride- Volatility Separations Process: Initial Studies

“…The oxalate product was washed with 0.2 M nitric acid, and calcined to the oxide at 450 to 480°C for 2 h. An SEM image of the PuO 2 from the oxalate presented in Figure 4-3 shows that this PuO 2 had particles ranging from <1 µm to a few µm. The XRD analyses confirmed the product was PuO 2 and a gamma energy analysis (GEA) of a nitric acid solution found 6×10 The 99.99-percent pure neptunium dioxide (NpO 2 ), originally prepared for use as a neutron dosimeter (Adair and Kobisk 1975), was confirmed by XRD analysis to be NpO 2 . Figure 4-4 shows that the NpO 2 was an aggregate of 1 to 10 µm-sized particles after crushing using a Wig-L-Bug grinder.…”

Fission Product Data Measured at Los Alamos for Fission Spectrum and Thermal Neutrons on 239Pu, 235U, 238U

“…Several sets of fissile materials used in the ILRR program ( 235 U, 238 U, and 239 Pu; 237 Np will not be discussed here) were procured and maintained by Oak Ridge National Laboratory (ORNL) for both reaction-rate measurements and cross-calibrating counting equipment at the participating laboratories [52][53][54][55][56][57][58][59][60][61]. The isotopic composition of each material (oxide and metal) was verified by mass spectrometry, as well as coulometry and sparksource mass spectrometry.…”

“…The weight percent of the major element and isotopic distribution for each target foil is provided in Table I. Impurity analysis of these materials is provided in Table II [61].…”