| 1. |
- Andersen Helland, Wenche, 1955-, et al.
(författare)
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Pragmatiske språkvansker og barnepsykiatri
- 2004
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Ingår i: Spesialpedagogikk. - : Utdanningsforbundet. - 0332-8457. ; :7, s. 14-19
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Det har dei siste åra vore ei aukande merksemd omkring språkfunksjonen til barn som er tilviste det psykiatriske behandlingsapparatet. I artikkelen er det gjort greie for reultata frå ein pilotstudie som viser komobiditet mellom psykiatriske vanskar og kommunikasjonsvanskar.
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| 2. |
- Birgersson, Martin, et al.
(författare)
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Density-functional theory applied to Rh(111) and CO/Rh(111) systems: Geometries, energies, and chemical shifts
- 2003
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Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 67:4, s. 1-04502
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Tidskriftsartikel (refereegranskat)abstract
- We present extensive density-functional theory (DFT) based calculations of the clean Rh(111) surface and of CO/Rh(111) overlayer systems. We study both ground-state structural properties and core-level shifts from differences in total energies at different coverages and adsorption sites. Most results are obtained using using norm-conserving or ultrasoft pseudopotentials. The overall reliability of the pseudopotential method is analyzed theoretically, and computationally by way of all-electron calculations. In general, core corrections are required in order to correctly simulate all-electron total energies, although the corrections are rather small for the systems considered here. Overall there is a very good agreement both between the pseudopotential and all-electron results as well as with high-resolution experimental spectra. The obtained agreement between theoretical and experimental core-level energies, however, requires that the correct geometrical parameters are used. For instance, inclusion of bucklings of the first Rh layer in the (2x2)-1CO and (root3x3)R30degrees-1CO overlayers is essential. For the overlayers studied here, different competing adsorption sites give almost the same frozen-lattice adsorption energies. However, the C 1s binding energy shows large differences between CO adsorbed in different sites. Thus calculations of the C 1s shifts allow us to predict the adsorption sites despite the small differences in ground-state energies. We also analyze sources of the shifts in terms of differences in Hartree potential and relaxation at different sites. As the DFT core eigenvalue lies above rather than below the core excitation energy some care is required in order to properly identify a relaxation energy in a DFT framework. In order to clarify the question we relate the DFT approach for core energies to approaches based on self-energies or the Hartree-Fock approximation.
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| 3. |
- Borg, Mikael, et al.
(författare)
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Experimental and theoretical surface core-level shifts of aluminum (100) and (111)
- 2004
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Ingår i: Physical Review B. - 1550-235X. ; 69
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Tidskriftsartikel (refereegranskat)abstract
- The surface core-level shifts of Al(111) and Al(100) have been measured using high-resolution core-level photoemission spectroscopy and calculated using density functional theory (DFT). For Al(100), the 2p core-level shift of the first (second) layer was determined to be –75 meV (+20 meV) from experiment and –71 meV (+20 meV) from the DFT calculations. For Al(111), the corresponding values are –27 meV (0 meV) from experiment and –14 meV (–) from the DFT calculations. Core-level splittings caused by the low-symmetry crystal fields at the (111) and (100) surfaces have also been studied. These splittings turn out to be much smaller than previously reported provided proper care is taken of the influence of the core hole screening and of core–valence exchange beyond the DFT level. Finally, the experimental Al 2p line shape was found to contain structure caused by a sharp no-phonon line and a broad and weak phonon replica.
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| 4. |
- Borg, Mikael, et al.
(författare)
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Structure and formation of the Al(100)-(root 5 x root 5) R27 degrees-Na phase: a LEED, DFT and HRCLS study
- 2002
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Ingår i: Surface Science. - 0039-6028. ; 515:2-3, s. 267-280
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Tidskriftsartikel (refereegranskat)abstract
- Adsorption of 0.2 ML Na on Al(1 0 0) at room temperature yields a disordered Al(1 0 0)-(1 x 1)-Na phase, which transforms reversibly to a well-ordered Al(1 0 0)-(root5 x root5)R27degrees-Na phase on cooling below 250 K. Based on low energy electron diffraction (LEED) and high resolution core-level spectroscopy (HRCLS) measurements, and on ab initio calculations, it is concluded that the structure of the Al(1 0 0)-(root5 x root5-)R27degrees-Na phase consists of Na atoms occupying substitutional sites. The structural parameters obtained from LEED and density functional theory analyses are in quantitative agreement. Adsorption of 0.2 ML Na at 100 K yields an Al(1 0 0)-c(2 x 2)-Na island structure, which transforms irreversibly into the (root5 x root5)R27degrees-Na structure by annealing above 190 K. The nature of the reversible and irreversible phase transformations to the (root5 x root5)R27degrees structure is investigated by HRCLS and LEED. (C) 2002 Elsevier Science B.V. All rights reserved.
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| 5. |
- Gustafson, Johan, et al.
(författare)
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Identification of Step Atoms by High Resolution Core Level Spectroscopy
- 2003
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Ingår i: Physical Review Letters. - 1079-7114. ; 91:5
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Tidskriftsartikel (refereegranskat)abstract
- Vicinal Rh(111) surfaces are studied with high resolution core level photoemission. We demonstrate the possibility to distinguish between the different kinds of surface atoms on these surfaces by virtue of their 3d core level binding energies. In particular, the low coordinated step atoms are found to exhibit a clear fingerprint in Rh 3d spectra. We demonstrate how this may be used to show that initial oxygen adsorption occurs on the steps and not on the terraces of the vicinal surfaces.
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| 6. |
- Gustafson, Johan, et al.
(författare)
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Self-limited growth of a thin oxide layer on Rh(111)
- 2004
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Ingår i: Physical Review Letters. - 1079-7114. ; 92:12
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Tidskriftsartikel (refereegranskat)abstract
- The oxidation of the Rh(111) surface at oxygen pressures from 10(-10) mbar to 0.5 bar and temperatures between 300 and 900 K has been studied on the atomic scale using a multimethod approach of experimental and theoretical techniques. Oxidation starts at the steps, resulting in a trilayer O-Rh-O surface oxide which, although not thermodynamically stable, prevents further oxidation at intermediate pressures. A thick corundum like Rh2O3 bulk oxide is formed only at significantly higher pressures and temperatures.
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| 7. |
- Kohler, L, et al.
(författare)
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High-coverage oxygen structures on Rh(111): Adsorbate repulsion and site preference is not enough
- 2004
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Ingår i: Physical Review Letters. - 1079-7114. ; 93:26
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Tidskriftsartikel (refereegranskat)abstract
- A new O induced structure on Rh(111) displaying a (2root3 x 2root3)R30degrees periodicity with an oxygen coverage of 2/3 has been studied by high resolution core level spectroscopy, scanning tunneling microscopy, and density functional theory. Although O favors fcc hollow sites in all other known phases, it occupies both fcc and hcp sites in this structure, which cannot be explained by pairwise adsorbate repulsion only. Both the (22root3 x 2root3)R30degrees and (2x2)-3O structures also exemplify that density-of-states contrast can lead to oxygen adatoms appearing as protrusions in scanning tunneling microscopy images.
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| 8. |
- Lundgren, Edvin, et al.
(författare)
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Two-dimensional oxide on Pd(111).
- 2002
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Ingår i: Physical Review Letters. - 1079-7114. ; 88:24, s. 246103-246103
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Tidskriftsartikel (refereegranskat)abstract
- The oxidation of Pd(111) leads to an incommensurate surface oxide, which was studied by the use of scanning tunneling microscopy, surface x-ray diffraction, high resolution core level spectroscopy, and density functional calculations. A combination of these methods reveals a two-dimensional structure having no resemblance to bulk oxides of Pd. Our study also demonstrates how the atomic arrangement of a nontrivial incommensurate surface can be solved by molecular dynamics in a case where experimental techniques alone give no solution.
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| 9. |
- Norgaard, B. L., et al.
(författare)
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Long term risk stratification of patients with acute coronary syndromes: characteristics of troponin T testing and continuous ST segment monitoring
- 2004
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Ingår i: Heart. - 1468-201X. ; 90:7, s. 739-44
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To examine the long term prognostic characteristics of troponin T testing and continuous multi-lead ST segment monitoring in combination with clinical and 12 lead ECG risk indicators in patients with acute coronary syndromes (ACS). PATIENTS AND DESIGN: Patients with suspected ACS (n = 213) were studied. Troponin T was analysed in blood samples collected during the first 12 hours after admission. Continuous vectorcardiography ST segment monitoring was performed for 24 hours and the number of ST vector magnitude episodes was registered. Patients were followed up for a median of 28 months. The end point was a composite of cardiac death and acute myocardial infarction. RESULTS: Thirty eight (18%) patients reached the composite end point. The median (interquartile range) time from study inclusion to the time of the composite end point was longer for patients predicted to be at risk by troponin T testing (n = 27) than for those predicted to be at risk by ST segment monitoring (n = 20) (8.4 (0.2-15) months v 0.3 (0.1-4.3) months, p = 0.04). Significant univariate predictors of the composite end point were age > or = 65 years, diabetes, previous myocardial infarction, congestive heart failure, use of beta blockers or diuretics at admission, 12 lead ECG ST segment depression at admission, troponin T concentration > or = 0.10 microg/l, and > or = 1 ST vector magnitude episodes. Age > or = 65 years, previous myocardial infarction, and troponin T concentration > or = 0.10 microg/l provided independent prognostic information after multivariate analysis of potential risk variables. The prognostic value of transient ischaemic episodes in ACS seems to be confined to the short term. CONCLUSIONS: Both biochemical and continuous ECG markers reflect an increased risk for patients with ACS; however, the methods exhibit different temporal risk characteristics.
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| 10. |
- Todorova, M, et al.
(författare)
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The Pd(100)-(root 5 x root 5)R27 degrees-O surface oxide revisited
- 2003
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Ingår i: Surface Science. - 0039-6028. ; 541:1-3, s. 101-112
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Tidskriftsartikel (refereegranskat)abstract
- Combining high-resolution core-level spectroscopy, scanning tunneling microscopy and density-functional theory calculations we reanalyze the Pd(100)-(root5 x root5)R27degrees-O surface oxide phase. We find that the prevalent structural model, a rumpled PdO(001) film suggested by previous low energy electron diffraction (LEED) work [Surf. Sci. 494 (2001) L799], is incompatible with all three employed methods. Instead, we suggest the two-dimensional film to consist of a strained PdO(101) layer on top of Pd(100). LEED intensity calculations show that this model is compatible with the experimental data of Saidy et al. (C) 2003 Elsevier B.V. All rights reserved.
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