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1
Content available remote

Studies of Solids and Adsorbates in Synchrotron Radiation Excited Soft X-Ray Fluorescence

100%
Nordgren J., Wassdahl N.
Acta Physica Polonica A
|
1992
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vol. 82
|
issue 2
251-262
EN
A progress report is presented on recent developments in soft X-ray emission spectroscopy using synchrotron radiation. Some key experiments are discussed demonstrating that new information can be gained by using synchrotron radiation for this purpose. Recent work on highly resolved soft X-ray emission from monolayers of adsorbed species is commented on and some perspectives are given regarding further developments expected from the third generation sources that are underway.
2
Content available remote

Identification of Painting Layers of Sennefer Tomb by Ion Beam Analysis

63%
Abd El Aal S.
Acta Physica Polonica A
|
2011
|
vol. 120
|
issue 1
144-148
EN
Egypt has many pharaonic tombs for kings, queens and noblemen. The Sennefer tomb, one of the most important nobleman tombs, is located in the southern hillside of Sheikh Abd El-Qurna - west side of Luxor. It is dated back to 1439-1413 B.C. (18th Dynasty) and is usually referred as the Tomb of Vines, due to the large part of the ceiling of the burial chamber. The vine tomb was carved inside a mountain, its walls are covered with plaster and were painted using the tempera technique (pigments mixed with organic binding medium). The analysis was performed by using particle-induced X-ray emission, microbeam particle-induced X-ray emission and optical microscope for the six samples from the Vine tomb such as white, black, red, yellow, blue and green pigments and for the ground layers of the tomb in order to identify the composition of plaster layers and pigments. The data about the nature of these materials are indispensable for conservation and cleaning.
3
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The Use of Analytical Methods in Evaluation of Coptic Wall Paintings Conservation - A Case Study

63%
Ali M., Abd El Aal S., Mahgoub G., Sihame A., Turos A., Korman A., Stonert A.
Acta Physica Polonica A
|
2011
|
vol. 120
|
issue 1
171-176
EN
Egypt has a lot of ancient monasteries and churches, which were decorated with different kinds of wall paintings. Structure of these wall paintings consists of support, plaster and painting layers. Paintings deterioration is primarily due to physicochemical, natural and human factors. The most detrimental factors are bat patches, old varnish and organic waste of birds. All these lead to the gradual disappearance of paintings. Modern technology of conservation is focused on application of new materials for cleaning of wall paintings. Here we report on the use of enzymes, for cleaning surface of coptic wall paintings. Analytical techniques such as particle induced X-ray emission, Fourier transform infrared and optical microscopy were used to evaluate the enzymatic cleaning processes of coptic wall paintings and to identify the chemical composition of red, yellow and white pigments. Particle induced X-ray emission results indicated that there is no change in the chemical composition of the materials and pigments due to enzymatic cleaning. Fourier transform infrared and optical microscopy results confirmed the stability of organic medium before and after treatment of different kind of patches.
4
Content available remote

Synchrotron Radiation Induced X-Ray Emission - SRIXE

63%
Kwiatek W.
Acta Physica Polonica A
|
1992
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vol. 82
|
issue 2
263-271
EN
The synchrotron radiation induced X-ray emission (SRIXE) technique was found very useful and sensitive for determination of trace elements content and distribution in different types of materials. Due to properties of synchrotron radiation the SRIXE technique became very unique and powerful for trace elements analysis. This paper describes the phenomena related to production of characteristic X-rays and principles of the method. The properties of SRIXE such as minimum detectable limit, spatial resolution, radiation damage, and depth sensitivity are also discussed. Selected applications are given to emphasize the usefulness of the technique.
5
Content available remote

Investigation of Trace Element Concentration in Diabetic Rat's Tissues

51%
Kowalska J., Krośniak M., Gryboś R., Kwiatek W.
Acta Physica Polonica A
|
2009
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vol. 115
|
issue 2
556-560
EN
Diabetes is one of the most frequent diseases in developing countries and thus there is a significant interest in diabetes related studies. It was found that vanadium compounds have glucose-lowering properties in diabetes and therefore it is very important to estimate the vanadium dose in diabetes treatment. On the other hand, the proper estimation of vanadium concentration is important due to side effects that occur in vanadium supplementation. In this study the influence of V(IV) and V(V) compounds with different ligands on the concentration of K, Ca, Mn, Fe, Cu, and Zn in selected rat's tissues was investigated by means of proton induced X-ray emission technique. As a result of the measurements it was found that the concentration of vanadium depends on the organ. The highest value was determined in spleen while the lowest in pancreas. It was also found that the concentration of other elements depends on the presence of vanadium and its concentration. The most meaningful influence of vanadium presence was on iron concentration in spleen, on copper and zinc in kidney, and on manganese in pancreas.
6
Publication available in full text mode
Content available

Electronic Structure of ZnS:Co Semiconductors: X-ray and Optical Spectroscopy Studies

51%
Surkova T., Galakhov V., Godlewski M.
Acta Physica Polonica A
|
2003
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vol. 103
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issue 6
703-708
EN
Experimental studies of X-ray photoelectron and Co L_α X-ray emission spectra of the ZnS:Co semiconductor were carried out. It was established that Co ions are in a Co^{2+} configuration and that the Co 3d impurity states are localized above the top of the valence band by 1.0±0.2 eV.
7
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Investigation on Zinc Selenide and Copper Selenide Thin Films Produced by Chemical Bath Deposition

51%
Durdu B., Alver U., Kucukonder A., Söğüt Ö., Kavgacı M.
Acta Physica Polonica A
|
2013
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vol. 124
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issue 1
41-45
EN
The zinc selenide and copper selenide thin films were deposited by chemical deposition technique on glass substrates. For both films, sodium selenosulphate was used as a selenide ion source in an alkaline solution. The X-ray diffraction patterns show that the ZnSe has a cubic structure and Cu_3Se_2 film has a tetragonal structure. The relative intensity K_ β / K_ α of zinc and copper selenide thin films has been measured by using a ^{241}Am radioisotope source (75 mCi). The obtained results were compared with the theoretical values.
8
Content available remote

Compensation of Roentgen Exciting System Instability in Conducting X-Ray Fluorescence Analysis of Bioassays

51%
Galchenko S., Kirilenko E., Fokov G.
Acta Physica Polonica A
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2011
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vol. 120
|
issue 3
531-535
EN
Detailed analysis of the backscattering peak in the X-ray fluorescence spectrum was carried out using the Monte Carlo method which is the base of the computer code "SNEGMONT" for simulating the transport of electrons and photons. The calculations show that the intensity of the backscattering peak is directly proportional to the intensity of the exciting radiation. It was found that the intensity of analyzed elements' lines has a strict relation with the intensity of the backscattering peak. The example of determination of lead and zinc concentrations in bioassay is presented. The simulation of an eightfold change of the exciting X-rays intensity which taking into account the obtained strict relation allows to determine the true concentration of elements with an error of no more than 3%.
9
Content available remote

Fluorescence Processes and Scintillation of CeF_{3} Crystal Excited by UV and X-Ray Synchrotron Radiation

51%
Pédrini C., Belsky A., Moine B., Bouttet D.
Acta Physica Polonica A
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1993
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vol. 84
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issue 5
953-957
EN
Photoluminescence properties of CeF_{3} have been investigated. Two kinds of emitting centers have been identified: regular Ce^{3+} sites exhibiting two close emission bands (285 and 300 nm) and a fast fluorescence (20 ns) and several physically different perturbed Ce^{3+} sites giving rise to a broad emission band near 340 nm and a longer fluorescence (30-40 ns) the decay time of which varies with wavelength. An energy transfer occurs between these two kinds of centers. Scintillation properties have been studied under UV and X-ray excitation. The additional fast decay always observed at short time under ionizing radiation is interpreted by a temperature dependent luminescence quenching phenomenon due to high excitation density.
10
Publication available in full text mode
Content available

Analysis of Atmospheric Aerosols Using the Lisbon Nuclear Microprobe

51%
Rita E., Alves L., Reis M., Rodrigues F., Fialho P., Soares J.
Acta Physica Polonica A
|
2001
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vol. 100
|
issue 5
781-788
EN
The nuclear microprobe installed at Instituto Tecnológico e Nuclear, in Lisbon, was used in the analysis of aerosols collected at the Azores islands. Samples from two different aerosol groups were analysed. One referred to aerosols that were carried from North America and the other one contained aerosols that were carried from the Sahara desert and crossed over Europe. Coarse and fine fractions were analysed for each aerosol group and two-dimensional elemental maps were constructed, which allowed the identification of several individual particles. For particles of interest, elemental spatial correlations and dimensions were determined and point analysis was also carried out (depth information was achieved by fitting Rutherford backscattering spectra). Some of these particles are quite interesting. For instance, in the fine fraction of the aerosols that were carried from North America, particles were found with Cu and Cl in the atomic proportion 1:2 and with dimensions 15×15×15μm^3, and in the corresponding coarse fraction a particle with K and S was identified, with dimensions 28×35×30μm^3. Some differences were found between the aerosols groups. One example of these are Ti particles (fine fraction) and Rb (coarse fraction) that were identified in one group (Sahara desert and Europe), but not in the other
11
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Recombination Luminescence in Ca_{3-x}Cd_xGa₂Ge₃O₁₂ Garnets Doped with Eu³⁺ Ions

51%
Kostyk L., Luchechko A., Novosad S., Panasyuk M., Rudko M., Tsvetkova O.
Acta Physica Polonica A
|
2018
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vol. 133
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issue 4
943-947
EN
The results of the investigations of X-ray excitation spectra, thermostimulated luminescence and influence of light illumination on the thermoluminescence glow curves of Eu³⁺-doped Ca_{3-x}Cd_xGa₂Ge₃O₁₂ garnet polycrystalline samples are presented. It is shown that Ca_{3-x}Cd_xGa₂Ge₃O₁₂ polycrystalline samples are characterized by intrinsic luminescence, which consists of several components. The nature of intrinsic luminescence is discussed. It is suggested that the nature of thermoluminescence glow peak near 150 K is connected with the [(V_{Ge}+V_{O})¯-F⁺] associations formed under X-ray irradiation at 85 K. The influence of light illumination on the TSL intensity of the preliminary X-ray irradiated samples is shown.
12
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X-ray Diffraction and Elemental Analysis of Medical and Environmental Samples

51%
Bielecka K., Kurtek W., Banaś D., Kubala-Kukuś A., Braziewicz J., Majewska U., Pajek M., Wudarczyk-Moćko J., Stabrawa I.
|
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vol. 125
|
issue 4
911-918
EN
The results of the elemental and chemical composition analysis of human medical samples (blood, serum, hair, urine, tooth, kidney stones, gallstones) and environmental samples (slag, cereal, vegetables, flour, pork bones, pork meat, fish) are presented. The analysis were performed by application of the total reflection X-ray fluorescence, wavelength dispersive X-ray fluorescence and X-ray powder diffraction methods. With X-ray fluorescence methods the following elements were identified: O, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Se, Br, Rb, Sr, Zr, I, Ba, and Pb, whose concentrations were from a few ng/g to tens of percent. For some samples the elemental analysis was extended by X-ray powder diffraction measurements. With this method the chemical composition was determined. In the paper the experimental setups, methodology of samples preparation and methods of carrying out the measurements are described. As an example the X-ray spectra registered for gallstone sample are discussed in detail. Finally, the results of X-ray diffraction and elemental analysis for selected medical and environmental samples are summarized.
13
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Iron Containing Supplement Biofer Investigated by X-ray Fluorescence, Energy Dispersive X-Ray Spectroscopy and Mössbauer Spectroscopy

51%
Brzozowski R., Szałański P., Kaźmierczak J., Polański K., Pruba M., Moneta M.
Acta Physica Polonica A
|
2015
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vol. 128
|
issue 5
905-907
EN
Iron, an important microelement essential to the functioning of the body, plays a special role in the process of respiration. There are more and more new products available on the pharmaceutical market. Some of them were the subject of previous studies, especially by using the Mössbauer spectroscopy. One of the latest is Biofer. For the present tests three tablets from three different production series of Biofer were used for examination of elemental composition using the X-ray fluorescence and energy dispersive X-ray spectroscopy methods. Information about oxidation of iron contained in the tablets was obtained with by means of the Mössbauer spectroscopy.
14
Content available remote

Study of Mo-Ni Alloys by X-Ray Spectroscopies

51%
Ławniczak-Jabłońska K., Heinonen M., Inoue J., Tohyama T.
Acta Physica Polonica A
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1993
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vol. 83
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issue 1
115-124
EN
Band structure investigations of the random MoNi_{4} and MoNi_{3} alloys, performed by emission and photoelectron spectroscopy, is reported. The X-ray emission and X-ray photoelectron spectra allowed to study the occupied valence band states below Fermi level. These techniques gave the full description of changes in the density of valence electron states distribution due to substitution of Mo atoms into the fcc Ni lattice up to 25 at%. The analysis of the emission and photoelectron spectra led to clear distinction between the changes in spectra caused by density of states structure and by additional effects involved in creation of the particular spectra. The experimental data are compared with the density of states calculated using coherent potential approximation and linear muffin-tin orbital methods.
15
Content available remote

Luminescence and Luminescence Kinetics of Gd_{3}Ga_{5}O_{12} Polycrystals Doped with Cr^{3+} and Pr^{3+}

51%
Mahlik S., Kukliński B., Grinberg M., Kostyk Ł., Tsvetkova O.
|
|
issue 1
117-121
EN
In this paper spectroscopic investigations of Gd_3Ga_5O_{12} (GGG) polycrystals, containing Cr^{3+} and intentionally doped with Pr^{3+} of concentrations 0.5, 1 and 1.5 mol% are presented. We have measured the steady state luminescence and luminescence excitation spectra, as well as the time resolved spectra and luminescence kinetics. The main goal was to investigate the excitation energy transfer from lattice to impurity and between impurities. We found that relative intensity of Cr^{3+} and GGG lattice luminescence decreased when material was doped with Pr^{3+}. On the other hand, time resolved spectroscopy and luminescence decay measurements showed that the Cr^{3+} and GGG lattice luminescence decays were independent of Pr^{3+} content. The lifetime of Pr^{3+} luminescence related to ^{1}D_{2} → ^{3}H_{4} and ^{3}P_{0} → ^{3}H_{4} transitions decreased with concentration of Pr^{3+}, which was attributed to the concentration luminescence quenching. No energy transfer between GGG lattice defects and Cr^{3+}, and Pr^{3+} ions was observed. We proposed the model of radiative recombination of electron and hole, which took place through three independent pathways: by GGG host emission that peaked at 12750 cm^{-1}, by Cr^{3+} luminescence that peaked at 15400 cm^{-1}, and by Pr^{3+} luminescence.
16
Content available remote

Optical Investigation of ZnO Nanowires

51%
Martínez-Criado G., Hernández-Vélez M., Letard I., Cros A., Cantarero A., Mínguez-Bacho I., Susini J., Tucoulou R., Sans J., Sanz R., Vázquez M.
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issue 2
369-373
EN
In this study we report the application of synchrotron X-ray fluorescence, photoluminescence and Raman scattering techniques to the analysis of the incorporation of impurities in unintentionally doped ZnO nanowires. Highly ordered one-dimensional ZnO arrays were fabricated by an oxidation process of Zn metal electrodeposited in nanoporous anodic alumina template. X-ray fluorescence data show the contribution of residual elements into the ZnO nanowires growth. A rough analytical quantification of the main light and heavy chemical contents derives impurity concentrations below 1%. The optical efficiency of ZnO nanowires is strongly affected by non-radiative centers up to temperatures as low as 100 K. The photoluminescence was found to be totally dominated by optical transitions associated with the anodic alumina template. Finally, the Raman scattering provides no evidence of local vibrational modes or secondary phases, but it shows the unambiguous signature of the ZnO hexagonal phase.
17
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Recombination Processes in PbWO_{4}:Tb^{3+} Crystals

51%
Novosad S., Kostyk L., Novosad I., Tsvetkova O.
|
|
issue 1
143-145
EN
In the paper the results of investigations of X-ray excitation spectra, thermostimulated luminescence and the influence of light illumination on the thermoluminescence glow curves of pure and Tb-doped PbWO_{4} crystals are presented. It is suggested that the F^{-}-centres are formed in PbWO_{4} crystals at filling oxygen vacancies near Pb^{3+} ions to three electrons under X-ray irradiation at 90 K. The nature of 108 K thermostimulated luminescence peak is connected with the [(WO_{3} + F^{-})-Pb^{3+}] associations. It was established that thermal or optical destruction of this peak leads to appearance of the radiative transitions of excitons localized near the [(WO_{3} + F)-Pb^{2+}] complex centres.
18
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Examination of the Change of the Characteristic X-Rays of the Zinc in Fluorine- and Boron-Doped ZnO Thin Films

51%
Söğüt Ö., Kerli S., Cengiz E., Apaydın G.
Acta Physica Polonica A
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2018
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vol. 133
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issue 5
1124-1128
EN
In this study, K_{β}/K_{α} X-ray intensity ratios of zinc in pure zinc, undoped ZnO thin film and boron and fluorine-doped ZnO thin films have been investigated. These samples have been excited by 59.5 keV γ-rays from a ^{241}Am annular radioactive source. K X-rays emitted by the samples have been counted using an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. The K_{β}/K_{α} X-ray intensity ratios of the doped ZnO thin films have been compared with that of the undoped ZnO thin film. The deviations between the results can be explained by delocalization and/or charge transfer phenomena causing change in valence electronic configuration of zinc.
19
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The Influence of Europium Impurity on the Recombination Luminescence in Y₂O₃

51%
Novosad S., Novosad I., Bordun O., Kostyk L., Bordun I., Tuzyak O.
Acta Physica Polonica A
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2018
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vol. 133
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issue 4
806-810
EN
In this work the researched results of the spectral characteristics of the luminescence and the thermostimulated luminescence curves of Y₂O₃ and Y₂O₃:Eu ceramic materials at the X-ray excitation in the 85-295 K range were generalized. Considering the features of Y₂O₃ crystal structure and the possibility of the formation of the short-lived and stable hole and electron centers of V- and F-type by the ionizing radiation X-ray luminescence spectrum of ceramics at 85 K is fitted into the elementary Gaussian shape bands with the maxima near 3.40, 3.06, 2.67, 2.33, 2.09, and 1.91 eV. The main 3.40 and 3.06 eV bands of the luminescence are caused by the self-trapped excitons of (YO₆)⁹¯ complex, when the cation is localized in the field of the trigonal (C_{3i}) and monoclinic (C₂) symmetries. The emission at 2.67 eV and the weak bands in the 1.65-2.61 eV region are considered as the radiation of excitons localized on the anion vacancies and the electron centers of F-type (F⁺, F and F¯). The thermoluminescence of Y₂O₃ in the 186 and 204 K main peaks range is connected with the thermal destruction of the self-trapped states of O¯ ions that located in the field of the trigonal and monoclinic symmetries. The activator bands caused by ⁵D→ ⁷F_{j} electronic transitions in Eu³⁺ are only observed in the X-ray and thermostimulated luminescence spectra of Y₂O₃:Eu ceramics. It was assumed that both at the X-rays irradiation and an optical excitation in the band of the charge transfer of Y₂O₃:Eu sample the energy goes to Eu³⁺ through (Eu²⁺O¯) complexes (states) of the charge transfer.
20
Content available remote

Parallel Mappings as a Key for Understanding the Bioinorganic Materials

45%
Kuczumow A., Nowak J., Chałas R.
Acta Physica Polonica A
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2009
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vol. 115
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issue 2
482-488
EN
Important bioinorganic objects, both living and fossilized are as a rule characterized by a complex microscopic structure. For biological samples, the cell-like and laminar as well as growth ring structures are among most significant. Moreover, these objects belong to a now widely studied category of biominerals with composite, inorganic-organic structure. Such materials are composed of a limited number of inorganic compounds and several natural organic polymers. This apparently simple composition leads to an abnormal variety of constructions significant from the medical (repairs and implants), natural (ecological effectiveness) and material science (biomimetic synthesis) point of view. The analysis of an image obtained in an optical microscope, optionally in a scanning electron microscope is a topographical reference for further investigations. For the characterization of the distribution of chemical elements and compounds in a material, techniques such as X-ray, electron- or proton microprobes are applied. Essentially, elemental mappings are collected in this stage. The need for the application of an X-ray diffraction microprobe is obvious and our experience indicates on the necessity of using the synchrotron-based devices due to their better spatial resolution and good X-ray intensity. To examine the presence of the organic compounds, the Raman microprobe measurements are good options. They deliver information about the spatial distribution of functional groups and oscillating fragments of molecules. For the comprehensive investigation of bioinorganic material structural and chemical features, we propose the following sequence of methods: optical imaging, elemental mapping, crystallographic mapping, organic mapping and micromechanical mapping. The examples of such an approach are given for: petrified wood, human teeth, and an ammonite shell.
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