Determination of Trace Quantities of Uranium by Neutron Activation Analysis.

Modern trends in activations analysis vol. 2

“…An important feature of bremsstrahlung is its anisotropic character as the produced gamma-rays are peaked forward. The angular distribution is described by Schiff [49] 7 0 = intensity at 0°f rom the axis of the incident electron beam; 1 (6) = intensity at 6 degrees from the axis; Ei= exponential integral; E= incident electron energy; N= number of target nuclei per cm 3 ; x= target thickness in cm.…”

“…In 1963, Lightowlers [48] performed activation analysis on diamonds for manganese, sodium, and copper using the classical peak area method, indicating concern about the accuracy of the method. Decat, Van Zanten and Leliart [49] used the Covell method, apparently without similar concern.…”

“…accelerator with an energy of [40][41][42][43][44][45][46][47][48][49][50] MeV. Although we placed the samples about 1 meter away from the target, the dose rate with this accelerator was much higher, and we were able to irradiate for twice as long.…”

“…Deuteron ActivationWhen deuterons are used for activation, many radionuclides are produced from the stable isotopes of calcium. Of these, calcium-48 can be separately determined by measuring the high energy gamma rays of 8.8 minute calcium-49 formed by the reaction48 Ca(d,p)49 Ca. The 4 hour activity produced from calcium-42 and 43 served as a measure of total…”

Determination of uranium isotopes in human bone ash

“…The lower limit of detection at the 95% confidence level for uranium is 1 ng by fluorimetry (13). The sensitivity of neutron activation analysis is estimated to be 0.05 ng (10,14). These measurement techniques directly quantitate the 238U mass and provide no information on the 234U/238U and 235U/238U activity ratios in the sample.Analytical methods are available for the determination of the isotopic uranium concentration in soil, sediments and bioassay samples by alpha spectrometry (13,(15)(16)(17).…”