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The first hard x-ray beamline at BESSY II has been installed by BAM and PTB at a superconducting 7 T wavelength shifter. The main optical elements of the beamline are a double-multilayer monochromator and a double-crystal monochromator. Depending on the application, the two devices are used separately or in-line. The main applications of the monochromatic radiation with photon energies up to 60 keV are x-ray fluorescence analysis, micro computed tomography, x-ray topography, detector calibration and reflectometry. Calculable undispersed radiation up to 200 keV is available for radiometric applications.
Large-volume instrumental photon and neutron activation analysis (IPAA resp. INAA) was used for
investigation of shredded electronic waste material. Sample masses from 1 to 150 grams were analysed
to obtain an estimate of the minimum sample size to be taken to achieve a representativeness
of the results which is satisfactory for a defined investigation task. Furthermore, the influence of
irradiation and measurement parameters upon the quality of the analytical results were studied. Finally,
the analytical data obtained from IPAA and instrumental neutron activation analysis (INAA),
both carried out in a large-volume mode, were compared. Values within the limits of satisfactory
agreement were found only partially. Analytical process control using on-site X-ray fluorescence
analysis performed during recycling of electronic waste is currently under development.
In activation analysis of traces in small samples, the non-equivalence of the activating radiation doses of sample and calibration material gives rise to sometimes tolerable systematic errors. Conversely, analysis of major components usually demands high trueness and precision. To meet this, beam geometry activation analysis (BEAMGAA) procedures have been developed for instrumental photon (IPAA) and neutron activation analysis (INAA) in which the activating neutron/photon beam exhibits broad, flat-topped characteristics. This results in a very low lateral activating flux gradient compared to known radiation facilities, however, at significantly lower flux density. The axial flux gradient can be accounted for by a monitor-sample-monitor assembly. As a first approach, major components were determined in high purity substances as well as selenium in a cattle fodder additive.