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EN
The neutron activation analysis procedure was used to determine the concentration of 42 elements: Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Ni, Co, Zn, As, Se, Br, Rb, Sr, Zr, Nb, Mo, I, Ag, Cd, Sb, Ba, Cs, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, W, Au, Hg, Th, and U accumulated in mosses sampled for testing in September and October 2011 in the Opole Province (Southern Poland). Samples of different moss species were collected near the intersections of the grid lines marked on the map of the province. The distance between the points was approximately 20 km. The analysis of the results made it possible to identify the places of increased deposition of element-pollutants and to indicate the potential sources of emission. Factor analysis revealed four components, two of which are of definite anthropogenic origin. The possible sources of elements are local industry and farming, and distant heavy industry complexes. The results have demonstrated the increased content of Cr, Cd, Hg, and U in moss samples collected in agricultural areas located in the southern part of the province. It has been concluded that the industrial areas of Rybnik and Ostrava and Karvina Coal Basin may be the potential source of emission of these elements.
PL
Metodą neutronowej analizy aktywacyjnej oznaczono stężenia 42 pierwiastków: Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Ni, Co, Zn, As, Se, Br, Rb, Sr, Zr, Nb, Mo, I, Ag, Cd, Sb, Ba, Cs, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, W, Au, Hg, Th i U, zakumulowanych w mchach pobranych do badań we wrześniu i w październiku 2011 roku na terenie województwa opolskiego (południowa Polska). Próbki różnych gatunków mchów pobierano w bliskiej odległości od miejsc przecięcia linii siatki kartograficznej naniesionych na mapę województwa. Odległości pomiędzy punktami wynosiły ok. 20 km. Analiza wyników badań umożliwiła wskazanie miejsc zwiększonej depozycji zanieczyszczeń wraz ze wskazaniem potencjalnych źródeł ich emisji. Wykazano m.in. zwiększoną zawartość Cr, Cd, Hg i U zakumulowanych w próbkach mchów pobranych do badań na obszarach rolniczych położonych na południu województwa. Stwierdzono, że potencjalnym źródłem emisji mogą być uprzemysłowione tereny Rybnickiego i Ostrawsko-Karwińskiego Zagłębia Węglowego. Badania prowadzono w ramach projektu Environmental studies in the South of Poland using nuclear and related analytical techniques.
EN
There is continued great interest in determining the trace element and heavy metal content of volcanic ash for a variety of reasons. The motivation stems from the desire to understand the geochemistry of volcanic ash in imbedded geological formations, the impact on seawater, and the possible release of toxic elements into the environment that may impact livestock grazing and water systems. Ash from volcanic plumes can go as high 8-18 km thus affecting climate and air traffic. We have employed Compton suppression neutron activation analysis (NAA) with thermal and epithermal neutrons to determine trace elements in volcanic ash from Indonesian eruption of Mount Merapi in October 2010. We found a wide range of elements, including several rare earth elements.
EN
Instrumental neutron activation analysis (INAA) procedure of elemental steel analysis has been elaborated. The reliability of results obtained by the described procedure has been proved in the frame of different proficiency testing/interlaboratory comparison (PT/ILC) programmes, in which the Institute of Nuclear Chemistry and Technology (INCT, Warsaw) took part since 2005. This work summarizes participation of INCT in these exercises and demonstrates the usefulness of INAA to the certification of steel reference materials.
EN
Neutron activation analysis (NAA) is a precise chemical multielemental method of analysis which is satisfactorily used for qualitative and quantitative analyses. Repeated irradiation is needed because of mal-determination of some elements due to peak overlap in qualitative analysis. In this study, NAA procedure has been modified using a neuro-fuzzy model to avoid repeated irradiation based on multilayer perceptrons network trained by the Levenberg-Marquardt algorithm. This method increases the precision of spectrum analysis in the case of strong background and peak overlap.
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