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Journal of Radioanalytical and Nuclear Chemistry - A contribution to the discussion about Vila Nova de São Pedro (VNSP) as a production centre of symbolic lithic artefacts, the origin of raw...  相似文献   
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An Eighteenth Dynasty Egyptian sealed pottery stored at the Museum of Aquitaine (Bordeaux, France) has been investigated using terahertz radiation, X-rays and neutrons. THz computed tomography revealed nondestructively the presence of content, whereas X-rays and neutrons analyzed more precisely the fabrication process and conservation of the pottery together with the nature of this content owing to higher spatial resolution and contrast. With neutron tomography, we determined the method used to seal the jar as well as the finer structure of the inner content. Neutron-induced prompt gamma spectroscopy was finally applied to measure the elemental composition of the content, which is supposed to consist of dried germinated seeds.  相似文献   
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A New Gamma-Ray Spectrum Catalog for PGAA   总被引:1,自引:0,他引:1  
A major obstacle to the use of the prompt gamma activation analysis (PGAA) method has so far been the lack of a suitable library. Therefore, new measurements have been performed at the PGAA facility at Budapest Research Reactor (BRR) in order to create a prompt -ray catalog for qualitative and quantitative analysis. Prompt -ray energies and associated k 0-factors have been determined by internal standardization. The resulting catalog contains prompt -ray data from neutron capture and other reactions such as (n,), and decay -ray data from short-lived reaction products. Data have been measured for nearly all stable elements, from hydrogen to uranium. Generally, data for several isotopes are given, to enable isotopic analysis as well.  相似文献   
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Since 1996 several applications of prompt gamma activation analysis have been performed at the new Budapest PGAA facility. This paper deals with the investigation of metal objects. We report the results of nondestructive detection of H in amorphous metals, multielement analysis of Roman bronze brooches and measurement of silver concentration in Hungarian coins.  相似文献   
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Isotope excited energy dispersive X-ray fluorescence (EDXRF) was used for the determination of the major components, silver and copper, of ancient coins. A ring shaped 125I source was used for excitation. Various methods were developed and compared for quantitative evaluation in order to eliminate matrix effects and the effects caused by the differences in geometry. The method proposed by the authors ensures determination with acceptable error using certified standard samples of alloys. The results of this method were compared with those of prompt gamma activation analysis (PGAA) and with data from contemporary written sources.  相似文献   
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A new gamma-ray spectrum catalog and library for PGAA   总被引:1,自引:0,他引:1  
New measurements have been performed at the PGAA facility at the Budapest Research Reactor (BRR) in order to create a prompt -ray catalog for qualitative and quantitative analysis. The measured spectra were accurately analyzed by HYPERMET-PC. Prompt -ray energies and associated -ray production cross-sections have been determined by internal standardization. The resulting catalog contains prompt -ray data from neutron capture and other reactions such as (n,), and decay -ray data from short-lived reaction products. Data have been measured for nearly all stable elements, from hydrogen to uranium. Generally, data for several isotopes are given, to enable isotopic analysis as well. The whole library, including elemental spectra, will be available as a book.  相似文献   
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Summary High-pressure metamorphic rocks showing a large range of chemical compositions were analyzed by PGNAA, XRF and solution ICP-MS for major components and a variety of trace elements. The large data set allowed a comparison of results from PGNAA to the established methods and revealed good agreement for most major elements and for Sc and Gd. For V, Cr, Co and Ni, PGNAA data are satisfactory only at high concentration levels. B, Cl and H were analyzed by PGNAA with very good precision, even at low concentrations.  相似文献   
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Recently, several archaeometrical projects were started on the prehistoric collection of the Hungarian National Museum. Among the analytical methods applied, non-destructive prompt gamma activation analysis (PGAA) has a special importance. Based on major-and trace components, characterization of stone tools and their raw materials were performed. Until now, 160 pieces from Carpathian Basin and from the surrounding area (Romania, Croatia, Ukraine, Poland and the Mediterranean region) have been analyzed, including both archaeological and geological pieces. Obsidian and Szeletian felsitic porphyry objects adequately separable with PGAA. Identification of high silica silex categories, however, is much more difficult.  相似文献   
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