Search Results

You are looking at 1 - 10 of 16 items for

  • Author or Editor: F. Adams x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract  

A computer program is described to perform the identification of isotopes in neutron activated samples. The γ-ray energies as obtained from a Ge(Li) γ-ray spectrum are compared with those of a library, containing data for about 250 isotopes. Isotopes whose γ-ray energies match closely with the unknowns are selected as possible constituents. Unlikely attributions are then eliminated by a careful inspection of the γ-rays found. Further exploitation of half-life, the way of production and the sensitivity for the given irradiation and measurement conditions, allow the selection of the most likely constituents in the source. The results of the automated identification agree closely to those obtained by an experienced investigator. The program is written in FORTRAN IV for a PDP-9 computer with a 16 K word memory.

Restricted access

Abstract  

A tabulation of about 2000 precise gamma-ray energies of about 250 isotopes formed through neutron activation has been used for the computer-assisted identification of the individual gamma emitters in complex gamma spectra. The identification consists in the calculation of the gamma-ray energies from the peak maximum position by taking into account the deviation from linearity of the spectrometer. Successive comparison of these energies with the energies of the tabulation allows then identification. The identification procedure was tested on a number of samples of varying complexity and satisfactory results were obtained.

Restricted access

Abstract  

The gamma ray energies of nearly all radionuclides formed by reactor neutron irradiation have been determined using high resolution Ge(Li) spectrometry. The re-producibility of the determinations is demonstrated and, to estimate the accuracy of the measurements, the results are compared with those of other investigators. In the energy range from 80 to about 1400 keV the accuracy for the most abundant gamma rays is better than 0.2 keV. The energies of gamma transitions above 1400 KeV may be less accurate. The data are compiled in an atomic number and in a photon energy sequence. A table of characteristic X-rays is also included. The tables are intended to be helpful in the identification of isotopes in neutron activation analysis.

Restricted access

Abstract  

Reactor neutron activation analysis of antimony, indium and cadmium in high-purity tin is interfered with by nuclear reactions on the tin matrix. For a number of interfering reactions the cross-sections were determined. The following results were obtained:122Sn(n,γ)123mSn:σth=0.145 barn, I=0.79 barn;122Sn(n,γ)113Sn:σth=0.52, I=25.4 barn;112Sn(n, 2n)111Sn:
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\bar \sigma _F = 290$$ \end{document}
microbarn;118Sn(n, α)115Cd:
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\bar \sigma _F = 0.252$$ \end{document}
microbarn; and114Sn(n, p)114m1In:
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\bar \sigma _F = 42.3$$ \end{document}
microbarn.
Restricted access

Abstract  

Two methods are described to determine indium and managenese in high-purity tin. In the first method indium and manganese are separated from the tin and antimony matrix activities on Dowex 1X8 anion exchanger. Tin and antimony are adsorbed in 10M HF while indium and manganese are eluted. In the second method the incident γ-ray intensity due to the tin matrix is reduced by placing a lead absorber between the sample and the detector. The reproducibility and the sensitivity of both methods are of the order of 10 ppb for manganese and of 1 ppb for indium for 1 g samples and a neutron flux of 1011 n·cm−2·sec−1.

Restricted access

Determination of trace impurities in tin by neutron activation analysis

I. Determination of arsenic, selenium and antimony

Journal of Radioanalytical and Nuclear Chemistry
Authors: W. Maenhaut, F. Adams, and J. Hoste

Abstract  

Arsenic, selenium and antimony were determined in four different tin samples. After distillation from HBr−H2SO4 medium arsenic and selenium were precipitated with thioacetamide, and antimony was subsequently separated by deposition on iron powder. The separated samples were counted on a high-resolution Ge(Li) γ-spectrometer. The sensitivity of the method is highly satisfactory.

Restricted access

Abstract  

Neutron activation analysis for bismuth in lead was performed through the separation and measurement of210Po, using two different extraction procedures. The reproducibility of the results was good for lead containing bismuth in higher concentrations. For high purity lead, variations in the bismuth content have been found by different analyses of the same sample, owing to inhomogeneity in the distribution of the Bi metal traces. An independent analysis of the same lead samples gave comparable Bi concentrations.

Restricted access