Detection Capability of 89Sr and 90Sr Using Liquid Scintillation Counting.

We developed a new method for simultaneous determination of 89Sr and 90Sr with an emphasis on detectability. The samples were digested, and Sr was chemically purified followed by a single count on a liquid scintillation counter in three windows overlapping the 90Sr, 89Sr, and 90Y peaks. Gamma spectrometry was used to measure 85Sr, added for chemical recovery.

Gamma Radioactivity Detection Limits and Associated Radionuclide Intakes Study in Artificial Human Urine Using Sodium-iodide and High-purity Germanium Detectors.

The performance of several gamma detectors was investigated for emergency urine bioassay screening of two radionuclides of concern: 131 I and 137 Cs. Unspiked artificial urine samples were measured for 10 min each on four different gamma detectors: 80% relative efficiency high-purity Ge detector in standard shielding, 102% low-background high-purity Ge detector equipped with top muon shield, 78% high-purity Ge well detector in standard shielding, and 4″ × 4″ NaI well detector in standard shielding. The measured gamma spectra were analyzed in two ways: (1) for the 364-keV peak region of 131 I and 662-keV peak region of 137 Cs and (2) for the total counts in the full energy spectrum (50-2,048 keV).

A Combined Density Functional Theory and Spectrophotometry Study of the Bonding Interactions of [NpO·M] Cation-Cation Complexes.

The equilibrium constants for [NpO·M] (M = Al, In, Sc, Fe) in μ = 10 M nitric acid and [NpO·Ga] in μ = 10 M hydrochloric acid media have been determined. The trend in the interaction strength follows: Fe > Sc ≥ In > Ga ≫ Al. These equilibrium constants are compared to those of previously reported values for NpO complexes with Cr and Rh within the literature.