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- Author or Editor: H. Morland x
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Abstract
Using particle induced prompt photon spectrometry, PIPPS, the ratos of the average stopping powers in samples and standards can be used to determine elemental compositions. Spiking the sample with a known amount of a non-analyte (lithium) compound with known stopping power, appropriate stopping powers in the samples can be determined by measuring the prompt gamma-ray yields induced in the spike. Using 5 MeV protons sodium and phosphorus were determined in ivory, while sodium was determined in geological samples. The method was tested by analyzing the standard reference materials SRM 91, 120c and 694.
Abstract
It is shown that by using non-analyte spiking to correct for range variations in sample and standard in proton-induced promt 
-ray spectrometry, the error introduced by using total ranges instead of effective ranges as a measure of target penetration is negligible, thus making knowledge of the appropriate thresholds irrelevant.
Abstract
It is shown by using non-analyte spiking to correct for range variations in sample and standard in proton-induced prompt 
-ray spectrometry, the error introduced by using total ranges instead of effective ranges as a measure of target penetration is negligible, thus making knowledge of the appropriate thresholds irrelevant.
Abstract
By measuring the yield of prompt gamma-rays, induced by energetic protons, the ratio of the ranges in sample and standard was used in the average cross-section method to determine fluorine. By spiking the sample with known amounts of a lithium compound, a nonanalyte element (absent from the sample), the appropriate ranges in the samples were determined by measuring the prompt gamma-rays induced in the non-analyte spike. Fluorine was determined in ores and ivory and the method was tested by analyzing the standard reference materials SRM 91, SRM 120c and SRM 694.
Abstract
Using particle induced prompt photon spectrometry, PIPPS, the ratios of deceleration values of charged particles in samples and standards can be used to determine elemental compositions. Through the spiking of samples and standards with a compound containing a known amount of a non-analyte element (lithium), to which a relative decelaration value is ascribed, appropriate relative deceleration values for samples and standards can be assessed by measuring the prompt 
-ray yields induced in the spike. Using 5 MeV protons this method was tested for the determination of chromium in a selection of reference standards using pure compounds of chromium as analyte standards. The application of both the average cross section as well as the average stopping power approaches were investigated.
Abstract
A major matrix effect that hampers nuclear analysis with charged particles is found in the range differences which charged particles experience in samples and comparators. The determination of lithium in ores was attempted by the previous determination of the ranges of protons therein. This was achieved by the homogeneous spiking of the ores with pure boron compounds of known composition and therefore known calculated ranges. Pure lithium compounds, also with known calculated ranges, were used as lithium standards. Determinations were carried out by proton-induced prompt photon spectrometry on nuclides of lithium and boron. Results obtained for standard reference ores, SRM 181 and-183, were in good agreement with the specificfied values.
Abstract
The prompt gamma-rays 1219-keV35Cl p/1, O/ and the 1763-keV35Cl p/2, O/ induced by 5 MeV protons were measured during irradiation of 15 pure chlorine compounds of known composition. Stopping powers of target materials were calculated from tables and the use of the Bragg-Kleeman rule. Apparent discrepancies in the measured yields could point to deviations from the Bragg-Kleeman rule and hence to molecular effects. The value of any molecular effects was found to be 
7.9%.
Abstract
The determination of sulphur through 
-ray spectrometry induced by 5 MeV protons was chosen to study the effect of dilution and spike addition on the stopping power of the matrix and applied to the determination of sulphur in coal. Changes in the matrix cannot be ignored even for the spiking technique.
