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1
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The Inelastic Mean Free Path οf Electrons. Research in Budapest, Warsaw, Wrocław and Clermont-Ferrand. Brief History and New Results

100%
Gergely G., Gurban S., Menyhard M., Jablonski A., Zommer L.
Acta Physica Polonica A
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2008
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vol. 114
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issue S
S-49-S-58
EN
The inelastic mean free path of electrons (IMFP) is an important material parameter for description of electron transport processes in solids. This parameter is particularly useful for quantifying the electron spectroscopies, in particular Auger electron spectroscopy, X-ray photoelectron spectroscopy, electron energy loss spectroscopy and elastic peak electron spectroscopy. In this work, a brief overview of the IMFP determination is presented. Generally, there are two groups of methods to determine the IMFP: (i) calculations using the theoretical model based on the experimental optical data, and (ii) calculations using theory relating the IMFP and the measured probability elastic electron backscattering from solids. Major advances in the development of the second group of methods were made in three laboratories; these advances are reviewed here. The elastic backscattering probability, in absolute or relative units, can be conveniently evaluated from the elastic peak intensity. However, much effort is needed to develop the theory for calculating the IMFP, which typically involves the Monte Carlo simulations of electron trajectories in solids. Presently, this theory and typical procedures of the spectra processing are implemented in the software package EPESWIN developed by Jablonski. In recent years, much attention is devoted to the phenomenon of the electron energy losses in the surface region of solids. Reliability of the theory of elastic backscattering is distinctly improved if this effect is taken into account.
2
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Olefin Hydrogenation with Single-Site Gold

100%
Szlachetko J., Lothschütz C., Sá J.
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vol. 125
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issue 4
940-943
EN
Butene hydrogenation activity is intimately connected with the occupied and unoccupied electronic states of gold active site. We prepare well-defined Au(III) sites in IRMOF-3 structure, and tuned the metal density-of-states by replacing the substituent group of the coordinating group at position 5. Resonant inelastic X-ray scattering experiments and theoretical calculations revealed an increase in unoccupied 5d states of Au when the substituent group is a donating group, which leads to a dramatic increase in catalytic activity.
3
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Materials Research on Archaeological Objects Using PIXE and Other Non-Invasive Techniques

88%
Miśta E., Stonert A., Korman A., Milczarek J., Fijał-Kirejczyk I., Kalbarczyk P., Wiśniewska A.
Acta Physica Polonica A
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2015
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vol. 128
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issue 5
815-817
EN
An interdisciplinary study of metallic objects from selected archaeological sites in Poland was performed. The aim of the project was to obtain information about the chemical composition and structural changes of the objects. Furthermore, the research results provided information about the technological process which was used to manufacture the artifacts. The materials research had a non- and micro-invasive character which is very important in this type of investigation. The main experimental tools were particle-induced X-ray emission supplemented with nuclear reaction thermal neutron (white beam) radiography, scanning electron microscopy with X-ray energy dispersive analysis, and laser ablation inductively coupled plasma mass spectrometry techniques. The results show that the artifacts were made by a secondary smelting process used in local metallurgy manufactures.
4
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Analysis of the Elemental Composition of the Artefacts from the Kosewo Archaeological Site

88%
Gójska A. M., Miśta E.
Acta Physica Polonica A
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2016
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vol. 130
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issue 6
1415-1419
EN
The Migration Period on the present Polish territories is considered as a time of depopulation of Oder, Warta, and Vistula basins. The prerequisite for such assumption is lack of the archaeological finds in these regions. In contrast, on the Mrągowo Lake District and in the Lyna basin, one can find wealth of burial crematory equipped with items from the Roman period and made in the Germanic style. The analyses using the physics techniques gives an opportunity to the meeting of history with the contemporary times and the lost things may see the light of present day. The discovered artefacts may constitute a source of knowledge, which, after analysis, will be able to fill the gaps on the map of settlements in the Polish territories. The energy-dispersive X-ray fluorescence system was used to analyze the set of Polish archaeological artefacts found in an excavation in Masurian Lakes District. The compact X-ray tube developed in the National Centre for Nuclear Research (NCBJ) was used as an X-ray source in the system designed for the energy-dispersive X-ray fluorescence studies. The X-ray fluorescence spectra of the artefacts were registered with the Amptek SDD spectrometer and the concentrations of elements were determined. The measurements show that the X-ray system developed in NCBJ with transmission type X-ray tube and the Amptek SDD spectrometer is an effective tool for chemical composition analyses of archaeological objects and can be successfully applied in archaeometry.
5
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FTIR Study of Multifunctional Coatings

88%
Paluszkiewicz C., Długoń E., Kwiatek W.
Acta Physica Polonica A
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2012
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vol. 121
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issue 2
551-554
EN
Nanoparticles of hydroxyapatite (HAp) or tricalcium phosphates (TCP) connected with fibrous phase create biomimetic system between the natural fibrous and ceramic materials building a bone. Chemical bonding between the implant and host tissue takes place through the phosphate layer, which is created on the bioactive implant surface when in contact with the body fluids environment. The Fourier transform infrared spectroscopy can yield microstructural information on the segment level complementary to the morphological information acquired from X-ray scattering as well as electron microscopy. The Fourier transform infrared method is applied to study thin films on different substrates. Moreover, the Fourier transform infrared microscope technique allows to obtain surface and cross-section maps in reflection and transmission modes. This leads to visualization of chemical imaging between substrates and films. In this work, the coatings with different addition of nanohydroxyapatite were deposited by electrodeposition method on titanium and Ti6Al4V alloys. Additionally, sublayers, such as TiO_2, were used to increase hydroxyapatite coating adhesion. The selection of suspension composition, depositing time and layer heat treatment conditions have the conclusive influence on the films parameters. All these experimental parameters were monitored during the sample preparation procedure. Changes in phase composition of biomaterials were determined by the Fourier transform infrared reflection technique based on focal plane array detection system. It has been found that results obtained by the Fourier transform infrared spectroscopy show the differences between the studied samples as well as that optimum time of HAp deposition was 90 s.
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