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Journal of Radioanalytical and Nuclear Chemistry
Authors: R. Bugoi, V. Cojocaru, B. Constantinescu, F. Constantin, D. Grambole, and F. Herrmann

Abstract  

Several fragments of ancient gold objects coming from an Eneolithic hoard and from Pietroasa Cloca cu Puii de Aur (The Golden Brood Hen with Its Chickens) hoard, unearthed on Romanian territory, and two Romanian native gold nuggets samples were analyzed using micro-PIXE technique. The purpose of the study was to clarify the metal provenance. Trace and minor elements (Cu, Te, Sn, Pb, Ti, Cr, V, Mn, Ta) and platinum group elements (PGE) concentrations were estimated. The presence of inclusions (micrometer size areas of composition different from the surroundings) was investigated. We found Si and Ca inclusions on two Eneolithic samples, and Ta inclusions on two samples from Pietroasa hoard. The measurements suggested an alluvial origin of gold for the Eneolithic samples and give indications for the possible gold ore sources of Pietroasa hoard.

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Abstract  

Et(Ind)2ZrCl2 and MAO co-catalyst, which polymerize ethylene and propylene, were heterogenized on partially dehydroxylated Davison silica 955, following the method of equilibrium adsorption. The dispersion of these catalyst components on the silica support was investigated by measuring the spatial concentration profiles of Si, Al, and Zr using a micro-PIXE technique. These components were found to be uniformly distributed over the support irrespective of the variation in the heterogenization procedures and the experimental conditions used. The Si∶Al ratios determined by the micro-PIXE technique were similar to those measured by the spectrophotometric method. However, the Al∶Zr ratios measured by the former were somewhat lower than those determined by the latter. Micro-PIXE measurements confirmed the presence of several trace impurities such as K, Ca, Ti, Fe, Ni, Cu, and Zn which may potentially poison the resulting catalyst.

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Abstract  

Adverse health effects of occupational exposures to metal-containing airborne particles have long been recognized. To reduce the adverse effects caused by metal-containing particles, it is important to make clear where they are from. SPM has been applied to the study of the sources of chromium, manganese, nickel and zinc in aerosol particles PM10. Micro-PIXE spectra of single particles were treated as fingerprints since each particle was characterized by its micro-PIXE spectrum. The sources of the metal-containing particles were identified using the fingerprints of single particles. The study shows that the major sources of the four kinds of metals in the air are metallurgic emission, vehicle exhaust, coal combustion and soil dust.

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Abstract  

Cellulose cylinders and circular filter papers spiked with known amounts of standard element solutions were prepared for studying some aspects of assessing measurement uncertainty of NAA and the elemental distribution measured by micro-PIXE analysis. Results for the cylinders showed strongly non-homogeneous distribution of the elements, both in radial and vertical directions, dominantly caused by osmosis driven transport of added liquid solution from the centre to the edges. Results for the thin cellulose filter paper disks exhibited weaker peaking of the standard element concentrations at the edges in comparison with the thick cylinders.

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Abstract  

Results of micro-PIXE analysis of senile plaques (SP) in Alzheimer's disease (AD) brain have been utilized to independently confirm levels of iron (Fe) as measured by LMMS in adjacent brain sections. LMMS concentrations were calculated based on the preparation and analysis of an iron calibration curve prepared in our laboratory. The LMMS standards consist of ironcis-dicyclohexano-18-crown-6 ether coordination complexes dissolved in Spurr's low viscosity embedding medium. To our knowledge, this is the first report of the use of micro-PIXE, with its spatial resolution and detection limits comparable to that of LMMS, in the validation of LMMS results. The agreement observed between results obtained for Fe by micro-PIXE and LMMS indicates that the use of our LMMS standards, at least in the case of Fe, yields accurate results.

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Summary  

Elérhetoség

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Summary  

The scanning microprobe facility of the 3 MV Tandetron accelerator at King Fahd University of Petroleum and Minerals (KFUPM) has been applied extensively in various fields, including geology. This paper reviews a number of geological investigations carried out on samples of gold-bearing rocks, phosphorite ores and volcanic sediments. Elemental composition and distribution maps across single mineral grains, fluid inclusions, grain boundaries and matrices were measured. The microscopic data obtained are discussed to understand fundamental geological processes and ore genesis, and the provenance of economically important trace minerals contained in these samples.

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Acta Geologica Hungarica
Authors: Gyula Szöőr, Péter Rózsa, Bart Vekemans, László Vincze, Freddy Adams, Imre Uzonyi, Árpád Z. Kiss, and Imre Beszeda

Impact material, especially magnetizable tiny grains (spherules, globules and platelets) of Barringer Meteor Crater (Arizona) was studied by combined nuclear analytical techniques. The samples were analyzed first by micro-proton-induced X-ray emission (PIXE) and deuteron-induced gamma-ray emission (DIGE) methods. In this way it was possible to determine the distribution of elements down to carbon. Using micro-synchrotron radiation X-ray fluorescence technique (SRXRF) we could determine medium and high atomic number trace elements such as the platinum-group metals. Our methodological developments made it possible for the first time to carry out quantitative analysis for more than 40 elements, providing new perspectives for the interpretation of the impact materials. Various compositions of the findings around the Barringer Crater were compared to analytical data of similar objects found in Carpathian Basin to elucidate their origin. This paper summarizes the more important results obtained by using ion beam microanalytical techniques.

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Abstract  

The elemental microdistributions of peripheral and central parts of the lichen Flavoparmelia caperata exposed to industrial pollution were analysed, in order to better understand the elements distribution patterns in relation to the lichen constitution, thereby increasing our knowledge on uptake and release mechanisms. Nuclear microscopy techniques were used to visualize elemental distributions in sample transepts and associate their concentrations to sample morphology. The distribution data of the elements studied suggests there is biological regulation of internal concentrations. Considering thallus parts, element-specific internal translocation should be taken into account as one more factor affecting lichen “memory length”.

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Acta Geologica Hungarica
Authors: Péter Rózsa, Gyula Szö?r, Zoltán Elekes, Bernard Gratuze, Imre Uzonyi, and Árpád Z. Kiss

Transylvania's Neolithic tools using PIXE, micro-PIXE and XRF. - Nucl. Inst. Meth. B. , 189 , pp. 373-377. Obsidian provenance studies of Transylvania's Neolithic tools using PIXE, micro-PIXE and XRF

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