Search Results

You are looking at 41 - 42 of 42 items for :

  • Author or Editor: E. Schweikert x
  • Chemistry and Chemical Engineering x
  • All content x
Clear All Modify Search

Abstract  

An analytical method is described for the determination of trace amounts of sulfur by charged particle activation analysis. The method consists of proton irradiation followed by a rapid radiochemical separation of the product nuclide,34m Cl. This procedure has been applied to a number of pure metal samples which range in sulfur content from 0.3 to 30 ppm. All analyses were repeated several times to ensure consistent results and to better evaluate experimental detection limits and systematic errors. The results indicate that sulfur determinations can be performed at a concentration of less than 1.0 ppm. Activation curves are presented for the reactions S(d,x)34mCl, S(p,x)34mCl, and the interfering reaction35Cl(p, pn)34mCl.

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors: J. McGinley, G. Stock, E. Schweikert, J. Cross, R. Zeisler, and L. Zikovsky

Abstract  

Heavy ion activation has been studied as a method for determining hydrogen. The reactions used [e.g.1H(7Li, n)7Be] are the “inverse” of well known reactions [e.g.7Li(p, n)7Be]. Nuclear activation parameters for the ion beams of interest (7Li2+,10B2+) have been studied. The analytical feasibility is demonstrated with the determination of hydrogen in titanium at the 100 and 30 ppm levels with relative precisions of 8 to 10%. Detection limits in titanium are in the 0.1 to 0.5 ppm range. Heavy ion bombardment is also accompanied by the emission of characteristic X-rays (“atomic” activation). The parameters governing X-ray emission and background production have been investigated. Experimental K and L X-ray yields from thick targets have been measured for many elements excited by On+ beams of 0.5 to 7 MeV/amu and Kr7+ beams of 0.5 to 1 MeV/amu. The simultaneous determination of trace elements at levels of 10 to several 100 ppm in microsamples (∼10−5 g) is demonstrated on biological specimens. K and L X-ray yields and corresponding detection limits have also been measured with the7Li2+ and10B2+ beams used for the nuclear activation of hydrogen. With these beams (∼6 MeV/amu) simultaneous nuclear and atomic activation is possible, yielding an unusual multielement trace analysis capability covering hydrogen and medium and high Z elements.

Restricted access