| 1. |
- Dubernet, M. L., et al.
(författare)
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Virtual atomic and molecular data centre
- 2010
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Ingår i: Journal of Quantitative Spectroscopy and Radiative Transfer. - 0022-4073 .- 1879-1352. ; 111:15, s. 2151-2159
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Tidskriftsartikel (refereegranskat)abstract
- The Virtual Atomic and Molecular Data Centre (VAMDC, http://www.vamdc.eu) is a European Union funded collaboration between groups involved in the generation, evaluation, and use of atomic and molecular data. VAMDC aims to build a secure, documented, flexible and interoperable e-science environment-based interface to existing atomic and molecular data. The project will cover establishing the core consortium, the development and deployment of the infrastructure and the development of interfaces to the existing atomic and molecular databases. It will also provide a forum for training potential users and dissemination of expertise worldwide. This review describes the scope of the VAMDC project; it provides a survey of the atomic and molecular data sets that will be included plus a discussion of how they will be integrated. Some applications of these data are also discussed.
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| 2. |
- Domashevskaya, E. P., et al.
(författare)
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Electronic structure of undoped and doped SnOx nanolayers
- 2013
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090 .- 1879-2731. ; 537, s. 137-144
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Tidskriftsartikel (refereegranskat)abstract
- Results of electronic structure investigations for tin oxide nanolayers obtained by tin magnetron sputtering and their following oxidation in air at different temperatures are presented. Using X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES) spectroscopy techniques it was shown that at the 240 degrees C anneal a predominant phase in the sample surface layers is tin monoxide. With the annealing temperature increase up to 450 degrees C the phase composition corresponds to tin dioxide. Rather high sorption sensitivity for the samples oxidized at 450 degrees C was found. The compositional model of the gap structure based on XANES and XPS data matching for SnOx nanolayers revealed occurrence of the crossed transitions with the energy of similar to 3.7 eV in the presence of two phases: the SnO and the SnO2 or SnOx with vacancies. Under surface doping of SnO2 nanolayers with palladium PdO and PdO2 is observed where PdO is the most intensive component. O-2 and H-2 multiple alternate exposures resulted in the disappearance of palladium dioxide and PdO recovery to the metallic Pd. Under Pd bulk doping of nanolayers PdO and PdO2 were observed in the surface layers. In this case PdO2 was presented by two types of particles different in size, one of them having the greatest binding energy of Pd 3d(5/2) (339.0 eV). (C) 2013 Elsevier B.V. All rights reserved.
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| 3. |
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| 4. |
- Kramida, A. E., et al.
(författare)
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Additions to the spectrum and energy levels and a critical compilation of helium-like and hydrogen-like boron, BIV and BV
- 2008
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Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 78:2
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Tidskriftsartikel (refereegranskat)abstract
- Using beam-foil spectroscopy, we have observed several new lines in the B IV and B V spectra. This experimental work was combined with theoretical calculations using ab initio and semi-empirical techniques. We have also critically evaluated all previous and recent experimental and theoretical data for these spectra. Complete data on wavelengths and energy levels based on this analysis are tabulated.
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| 5. |
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| 6. |
- Kramida, A. E., et al.
(författare)
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Additions to the spectrum and energy levels and critical compilation of doubly ionized boron, BIII
- 2008
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Ingår i: Physica Scripta. - : IOP Publishing. - 0031-8949 .- 1402-4896. ; 78:2
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Tidskriftsartikel (refereegranskat)abstract
- We have undertaken the study of the Li-like spectrum of doubly ionized boron, B III. The spectroscopic data have been obtained with beam-foil spectroscopy and high-resolution spark spectroscopy. The experimental work was combined with theoretical calculations using ab initio and semi-empirical techniques. About 50 new transitions have been observed, and most of the previously known lines have been measured with improved accuracy. We have also critically evaluated all previous and recent data for this spectrum. Complete data on wavelengths and energy levels based on this analysis are tabulated.
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| 7. |
- Ryabtsev, A N, et al.
(författare)
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Additions to the spectrum and energy levels and a critical compilation of singly-ionized boron, B II
- 2005
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Ingår i: Physica Scripta. - 0031-8949. ; 71:5, s. 489-501
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Tidskriftsartikel (refereegranskat)abstract
- We have undertaken a number of experimental studies of the structure of singly ionized boron, B II. Much of this work was initially motivated by a search for the "missing" 2s3s S-1 term. There was a surprising disagreement between theory and experiment for this level. In this context lots of data for B II were collected over the years, from beam-foil experiments, high-resolution spark spectroscopy and theoretical calculations. The new material, which includes more than 80 newly classified (or revised) spectral lines, has now been thoroughly analyzed. This was followed by a critical compilation of all known levels and lines of B II, along with the theoretical interpretation of the levels, classifications of the lines and calculated transition probabilities for most lines.
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| 8. |
- Domashevskaya, EP, et al.
(författare)
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XPS and XANES studies of SnOx nanolayers
- 2008
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Ingår i: Journal of Structural Chemistry. - New York : Springer. - 0022-4766 .- 1573-8779. ; 49:Suppl 1, s. 80-91
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents the results of our XPS (X-ray photoelectron spectroscopy) and XANES (X-ray absorption near edge structure) Studies of tin oxide nanolayers obtained by magnetron spraying of the metal and its further oxidation in air at different temperatures. It was shown that at 240 degrees C (annealing temperature), tin monoxide was dominant in the surface layer of the samples. When the temperature was increased to 450 degrees C, the phase composition corresponded to tin dioxide. Increased sorption ability was found for the samples oxidized at 450 degrees C. The band structure model of SnOx nanolayers obtained by superposition of the XANES and XPS data revealed cross transitions with energy similar to 3.7 eV in the presence of the SnO and SnO, phases. Surface doping of nanolayers with palladium gave the Pd, PdO, and PdO2 components, among which PdO was most intense. Alternate treatments with O-2 and H-2 gases led to the disappearance of palladium dioxide and the reduction of PdO to the Pd metal. After the volume doping of nanoplayers with palladium, the surface layer contained PdO and PdO2; the latter was represented by two types of particles with different sizes.
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| 9. |
- Ryabchikova, T., et al.
(författare)
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Rare-earth elements in the atmosphere of the magnetic chemically peculiar star HD 144897
- 2006
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Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 456:1, s. 329-338
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Tidskriftsartikel (refereegranskat)abstract
- Context. The chemically peculiar stars of the upper main sequence represent a natural laboratory for the study of rare- earth elements (REE). Aims. We want to check the reliability of the energy levels and atomic line parameters for the second REE ions currently available in the literature, and obtained by means of experiments and theoretical calculations. Methods. We have obtained a UVES spectrum of a slowly rotating strongly magnetic Ap star, HD 144897, that exhibits very large overabundances of rare- earth elements. Here we present a detailed spectral analysis of this object, taking effects of non- uniform vertical distribution (stratification) of chemical elements into account. Results. We determined the photospheric abundances of 40 ions. For seven elements (Mg, Si, Ca, Ti, Cr, Mn, Fe), we obtained a stratification model that allows us to produce a satisfactory fit to the observed profiles of spectral lines of various strengths. All the stratified elements but Cr show a steep decrease in concentration toward the upper atmospheric layers; for Cr the transition from high to low concentration regions appears smoother than for the other elements. The REEs abundances, which have been determined for the first time from the lines of the first and second ions, have been found typically four dex higher than solar abundances. Our analysis of REE spectral lines provides strong support for the laboratory line classification and determination of the atomic parameters. The only remarkable exception is Nd III, for which spectral synthesis was found to be inconsistent with the observations. We therefore performed a revision of the Nd III classification. We confirmed the energies for 11 out of 24 odd energy levels that were classified previously, and derived the energies for additional 24 levels of Nd III, thereby substantially increasing the number of classified Nd III lines with corrected wavelengths and atomic parameters.
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