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| Author | Hellar-Kihampa, H.; Potgieter-Vermaak, S.; De Wael, K.; Lugwisha, E.; van Espen, P.; Van Grieken, R. | ||||
| Title | Concentration profiles of metal contaminants in fluvial sediments of a rural-urban drainage basin in Tanzania | Type | A1 Journal article | ||
| Year | 2014 | Publication | International journal of environmental analytical chemistry | Abbreviated Journal | Int J Environ An Ch |
| Volume | 94 | Issue  |
1 | Pages | 77-98 |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | This study investigated concentration profiles of trace, rare earth and platinum group metals in fluvial sediments from the Pangani river basin (43,650 km2), one of the largest river basins in Tanzania, to assess its environmental quality. Sediment samples were collected in two distinct seasons from 12 representative sites of diverse land-use practices and characterised by ICP-MS after optimised microwave digestion. Ecological risks were assessed by evaluation of pollution index and comparison with legislated sediment quality guidelines (SQG). The results revealed contamination by some trace metals (e.g. Pb, V, Cu, Cr, Ni, Cd, As, Co, Mn and Zn) in concentrations ranging from 0.7 to 2940 mg kg−1, and four rare earth elements (Y, Ce, Nd, Yb) in concentrations ranging from 0.9 (Yb) to 500 mg kg−1 dry weight (Ce), which significantly exceeded the estimated background values at some stations. Palladium was the only platinum group element that was detected in quantifiable concentrations (0.33.5 mg kg−1). Concentrations of some trace metals exceeded the SQGs at some localised areas. Principal component analysis and multivariate correlations indicated geochemical characteristics of the area as the major control of metal concentrations and spatial variability. Organic matter and clay contents also played a significant role in metal distributions. Assessment of land-use practices upstream of the sampling locations was used to trace potential anthropogenic sources of metal enrichments, where highest levels were found in areas close to urban centres and agricultural activities. The study provides baseline data for future monitoring programs, and highlights the need for more comprehensive analysis involving a wider spatio-temporal scale and ecotoxicological risk assessment. | ||||
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| Language | Wos | 000329774500007 | Publication Date | 2013-05-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0306-7319 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.208 | Times cited | 5 | Open Access | |
| Notes | ; The participants of this research gratefully acknowledge the financial support of the Belgian Development Agency (BTC). The contribution of the Pangani Basin Water Board (PBWB), especially Ms Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns is greatly appreciated. We sincerely acknowledge the assistance of Mr. Elisa Dunstan Kiwelu of Ardhi University, Dar es Salaam, Tanzania in mapping the study area; Mr Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterisation; and Dr Valentine Kayawe Mubiana of the Department of Biology, University of Antwerp in ICP-MS analysis. The contributions of six anonymous reviewers, which greatly improved the manuscript for this paper, are highly appreciated. ; | Approved | Most recent IF: 1.208; 2014 IF: 1.295 | ||
| Call Number | UA @ admin @ c:irua:109234 | Serial | 5547 | ||
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| Author | Buczyńska, A.J.; Geypens, B.; Van Grieken, R.; De Wael, K. | ||||
| Title | Large-volume injection combined with gas chromatography/isotope ratio mass spectrometry for the analysis of polycyclic aromatic hydrocarbons | Type | A1 Journal article | ||
| Year | 2014 | Publication | Rapid communications in mass spectrometry | Abbreviated Journal | Rapid Commun Mass Sp |
| Volume | 28 | Issue |
1 | Pages | 1-9 |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | RATIONALE: Compound-specific stable isotope analyses of carbon require relatively large amounts of sample for reliable analyses. Commonly applied injections of 1 μL may thus be inefficient for samples with low concentrations of pollutants (e.g. air particulate matter) or when the amount of a sample is limited. METHODS: A Large-Volume Injection (LVI) method for carbon stable isotope ratio analysis of Polycyclic Aromatic Hydrocarbons (PAHs) was optimized in this study. Gas chromatography/combustion/isotope ratio mass spectrometry (GCCIRMS) and ion trap mass spectrometry (ITMS) were used for the determination of stable carbon isotope ratios and quantification of compounds, respectively. RESULTS: The optimized method resulted in very good reproducibility, even for the most volatile PAH, naphthalene, when a small amount of higher boiling co-solvent was used. No significant fractionation of isotope ratios could be seen and the recoveries of analytes were similar to or better than that of a splitless cold injection. CONCLUSIONS: Injection of 100 μL, instead of the commonly used 1 μL, increases the detection limit for PAHs significantly and/or simplifies the sample preparation step. Using our optimized method, stable carbon isotope ratios can be reliably measured in samples with concentrations of PAHs down to 0.050.1 ng μL1. | ||||
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| Language | Wos | 000328248300007 | Publication Date | 2013-12-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0951-4198 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.998 | Times cited | 5 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 1.998; 2014 IF: 2.253 | ||
| Call Number | UA @ admin @ c:irua:111677 | Serial | 5689 | ||
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| Author | Deng, S.; Verbruggen, S.W.; Lenaerts, S.; Martens, J.A.; Van den Berghe, S.; Devloo-Casier, K.; Devulder, W.; Dendoover, J.; Deduytsche, D.; Detavernier, C. | ||||
| Title | Controllable nitrogen doping in as deposited TiO2 film and its effect on post deposition annealing | Type | A1 Journal article | ||
| Year | 2014 | Publication | Journal of vacuum science and technology: A: vacuum surfaces and films | Abbreviated Journal | J Vac Sci Technol A |
| Volume | 32 | Issue |
1 | Pages | 01a123 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | In order to narrow the band gap of TiO2, nitrogen doping by combining thermal atomic layer deposition (TALD) of TiO2 and plasma enhanced atomic layer deposition (PEALD) of TiN has been implemented. By altering the ratio between TALD TiO2 and PEALD TiN, the as synthesized TiOxNy films showed different band gaps (from 1.91 eV to 3.14 eV). In situ x-ray diffraction characterization showed that the crystallization behavior of these films changed after nitrogen doping. After annealing in helium, nitrogen doped TiO2 films crystallized into rutile phase while for the samples annealed in air a preferential growth of the anatase TiO2 along (001) orientation was observed. Photocatalytic tests of the degradation of stearic acid were done to evaluate the effect of N doping on the photocatalytic activity. | ||||
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| Language | Wos | 000335847600023 | Publication Date | 2013-12-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0734-2101 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.374 | Times cited | 10 | Open Access | |
| Notes | ; The authors wish to thank the Research Foundation-Flanders (FWO) for financial support. The authors acknowledge the European Research Council for funding under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement Nos. 239865-COCOON and 246791-COUNTATO. The authors also acknowledge the support from UGENT-GOA-01G01513 and IWT-SBO SOSLion. J.A.M. acknowledges the Flemish government for long-term structural funding (Methusalem). J.D. acknowledges the Flemisch FWO for a postdoctoral fellowship. ; | Approved | Most recent IF: 1.374; 2014 IF: 2.322 | ||
| Call Number | UA @ admin @ c:irua:117296 | Serial | 5936 | ||
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| Author | De Baere, K.; Verstraelen, H.; Lemmens, L.; Lenaerts, S.; Dewil, R.; Van Ingelgem, Y.; Potters, G. | ||||
| Title | A field study of the effectiveness of sacrificial anodes in ballast tanks of merchant ships | Type | A1 Journal article | ||
| Year | 2014 | Publication | Journal of marine science and technology | Abbreviated Journal | J Mar Sci Tech-Japan |
| Volume | 19 | Issue |
1 | Pages | 116-123 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | Sacrificial anodes have become a standard practice for the protection of ballast tanks of merchant vessels against corrosive damage. A well protected tank should extend the life span of a ship and consequently enhances its economic value. An in situ survey comprising more than 100 merchant vessels provided the opportunity to measure the impact of these anodes on the life expectancy of these vessels. Contrary to the general belief of these anodes beneficial effect, no significant difference was found in our observations in terms of corrosion occurrence between ship populations with and without sacrificial anodes, across all ship ages. This may be explained by the highly variable conditions and the complex geometry in a ballast tank severely impede optimal and straightforward installation of these anodes in these tanks. Also, poorly placed anodes in it may harm the integrity of the coating of the tank. We therefore plead for uniform and clear rules on anode installation and inspection. | ||||
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| Language | Wos | 000332693300008 | Publication Date | 2013-07-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0948-4280 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 0.838 | Times cited | 3 | Open Access | |
| Notes | ; This work was financed by a BOF Academisation grant of the University of Antwerp and the Antwerp Maritime Academy. ; | Approved | Most recent IF: 0.838; 2014 IF: 0.805 | ||
| Call Number | UA @ admin @ c:irua:109348 | Serial | 5953 | ||
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| Author | Gielis, J.; Verhulst, R.; Caratelli, D.; Ricci, P.E.; Tavkhelidze, I. | ||||
| Title | On means, polynomials and special functions | Type | A1 Journal article | ||
| Year | 2014 | Publication | The teaching of mathematics | Abbreviated Journal | |
| Volume | 17 | Issue |
1 | Pages | 1-20 |
| Keywords | A1 Journal article; Educational sciences; Sustainable Energy, Air and Water Technology (DuEL) | ||||
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| Language | Wos | Publication Date | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1451-4966; 2406-1077 | ISBN | Additional Links | UA library record | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:128660 | Serial | 8327 | ||
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| Author | Mueller, K.; Krause, F.F.; Béché, A.; Schowalter, M.; Galioit, V.; Loeffler, S.; Verbeeck, J.; Zweck, J.; Schattschneider, P.; Rosenauer, A. | ||||
| Title | Atomic electric fields revealed by a quantum mechanical approach to electron picodiffraction | Type | A1 Journal article | ||
| Year | 2014 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 5 | Issue |
Pages | 5653 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | By focusing electrons on probes with a diameter of 50 pm, aberration-corrected scanning transmission electron microscopy (STEM) is currently crossing the border to probing subatomic details. A major challenge is the measurement of atomic electric fields using differential phase contrast (DPC) microscopy, traditionally exploiting the concept of a field- induced shift of diffraction patterns. Here we present a simplified quantum theoretical interpretation of DPC. This enables us to calculate the momentum transferred to the STEM probe from diffracted intensities recorded on a pixel array instead of conventional segmented bright- field detectors. The methodical development yielding atomic electric field, charge and electron density is performed using simulations for binary GaN as an ideal model system. We then present a detailed experimental study of SrTiO3 yielding atomic electric fields, validated by comprehensive simulations. With this interpretation and upgraded instrumentation, STEM is capable of quantifying atomic electric fields and high-contrast imaging of light atoms. | ||||
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| Language | Wos | 000347227700003 | Publication Date | 2014-12-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 197 | Open Access | |
| Notes | 246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; esteem2ta; ECASJO; | Approved | Most recent IF: 12.124; 2014 IF: 11.470 | ||
| Call Number | UA @ lucian @ c:irua:122835UA @ admin @ c:irua:122835 | Serial | 166 | ||
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| Author | Egoavil, R.; Gauquelin, N.; Martinez, G.T.; Van Aert, S.; Van Tendeloo, G.; Verbeeck, J. | ||||
| Title | Atomic resolution mapping of phonon excitations in STEM-EELS experiments | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 147 | Issue |
Pages | 1-7 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Atomically resolved electron energy-loss spectroscopy experiments are commonplace in modern aberration-corrected transmission electron microscopes. Energy resolution has also been increasing steadily with the continuous improvement of electron monochromators. Electronic excitations however are known to be delocalized due to the long range interaction of the charged accelerated electrons with the electrons in a sample. This has made several scientists question the value of combined high spatial and energy resolution for mapping interband transitions and possibly phonon excitation in crystals. In this paper we demonstrate experimentally that atomic resolution information is indeed available at very low energy losses around 100 meV expressed as a modulation of the broadening of the zero loss peak. Careful data analysis allows us to get a glimpse of what are likely phonon excitations with both an energy loss and gain part. These experiments confirm recent theoretical predictions on the strong localization of phonon excitations as opposed to electronic excitations and show that a combination of atomic resolution and recent developments in increased energy resolution will offer great benefit for mapping phonon modes in real space. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000343157400001 | Publication Date | 2014-05-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 22 | Open Access | |
| Notes | 246102 IFOX; 278510 VORTEX; 246791 COUNTATOMS; Hercules; 312483 ESTEEM2; esteem2jra3 ECASJO; | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:118332UA @ admin @ c:irua:118332 | Serial | 177 | ||
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| Author | Niermann, T.; Verbeeck, J.; Lehmann, M. | ||||
| Title | Creating arrays of electron vortices | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 136 | Issue |
Pages | 165-170 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We demonstrate the production of an ordered array of electron vortices making use of an electron optical setup consisting of two electrostatic biprisms. The biprism filaments are oriented nearly orthogonal with respect to each other in a transmission electron microscope. Matching the position of the filaments, we can choose to form different topological features in the electron wave. We outline the working principle of the setup and demonstrate fist experimental results. This setup partially bridges the gap between angular momentum carried by electron spin, which is intrinsic and therefore present in any position of the wave, and angular momentum carried by the vortex character of the wave, which can be extrinsic depending on the axis around which it is measured. (C) 2013 Elsevier B.V. All rights reserved. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000327884700021 | Publication Date | 2013-10-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 9 | Open Access | |
| Notes | FP7; Countatoms; Vortex ECASJO_; | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:112837UA @ admin @ c:irua:112837 | Serial | 538 | ||
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| Author | Lubk, A.; Javon, E.; Cherkashin, N.; Reboh, S.; Gatel, C.; Hytch, M. | ||||
| Title | Dynamic scattering theory for dark-field electron holography of 3D strain fields | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 136 | Issue |
Pages | 42-49 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Dark-held electron holography maps strain in crystal lattices into reconstructed phases over large fields of view. Here we investigate the details of the lattice strain-reconstructed phase relationship by applying dynamic scattering theory both analytically and numerically. We develop efficient analytic linear projection rules for 3D strain fields, facilitating a straight-forward calculation of reconstructed phases from 3D strained materials. They are used in the following to quantify the influence of various experimental parameters like strain magnitude, specimen thickness, excitation error and surface relaxation. (C) 2013 Elsevier B.V. All rights reserved. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000327884700006 | Publication Date | 2013-07-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 18 | Open Access | |
| Notes | European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference312483 – ESTEEM2); esteem2_jra4 | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:112836 | Serial | 766 | ||
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| Author | Martinez, G.T.; de Backer, A.; Rosenauer, A.; Verbeeck, J.; Van Aert, S. | ||||
| Title | The effect of probe inaccuracies on the quantitative model-based analysis of high angle annular dark field scanning transmission electron microscopy images | Type | A1 Journal article | ||
| Year | 2014 | Publication | Micron | Abbreviated Journal | Micron |
| Volume | 63 | Issue |
Pages | 57-63 | |
| Keywords | A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantitative structural and chemical information can be obtained from high angle annular dark field scanning transmission electron microscopy (HAADF STEM) images when using statistical parameter estimation theory. In this approach, we assume an empirical parameterized imaging model for which the total scattered intensities of the atomic columns are estimated. These intensities can be related to the material structure or composition. Since the experimental probe profile is assumed to be known in the description of the imaging model, we will explore how the uncertainties in the probe profile affect the estimation of the total scattered intensities. Using multislice image simulations, we analyze this effect for Cs corrected and non-Cs corrected microscopes as a function of inaccuracies in cylindrically symmetric aberrations, such as defocus and spherical aberration of third and fifth order, and non-cylindrically symmetric aberrations, such as 2-fold and 3-fold astigmatism and coma. | ||||
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| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000338402500011 | Publication Date | 2014-01-02 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0968-4328; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.98 | Times cited | 25 | Open Access | |
| Notes | FWO (G.0393.11; G.0064.10; G.0374.13; G.0044.13); European Research Council under the 7th Framework Program (FP7); ERC GrantNo. 246791-COUNTATOMS and ERC Starting Grant No. 278510-VORTEX. A.R. thanks the DFG under contract number RO2057/8-1.The research leading to these results has received funding fromthe European Union 7th Framework Programme [FP7/2007-2013]under grant agreement no. 312483 (ESTEEM2).; esteem2ta ECASJO; | Approved | Most recent IF: 1.98; 2014 IF: 1.988 | ||
| Call Number | UA @ lucian @ c:irua:113857UA @ admin @ c:irua:113857 | Serial | 831 | ||
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| Author | Schattschneider, P.; Löffler, S.; Stöger-Pollach, M.; Verbeeck, J. | ||||
| Title | Is magnetic chiral dichroism feasible with electron vortices? | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 136 | Issue |
Pages | 81-85 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We discuss the feasibility of detecting magnetic transitions with focused electron vortex probes, suggested by selection rules for the magnetic quantum number. We theoretically estimate the dichroic signal strength in the L2,3 edge of ferromagnetic d metals. It is shown that under realistic conditions, the dichroic signal is undetectable for nanoparticles larger than View the MathML source. This is confirmed by a key experiment with nanometer-sized vortices. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000327884700011 | Publication Date | 2013-07-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 64 | Open Access | |
| Notes | Countatoms; Vortex; Esteem2; esteem2jra3 ECASJO; | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:110952UA @ admin @ c:irua:110952 | Serial | 1750 | ||
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| Author | Guzzinati, G.; Clark, L.; Béché, A.; Verbeeck, J. | ||||
| Title | Measuring the orbital angular momentum of electron beams | Type | A1 Journal article | ||
| Year | 2014 | Publication | Physical review : A : atomic, molecular and optical physics | Abbreviated Journal | Phys Rev A |
| Volume | 89 | Issue |
Pages | 025803 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The recent demonstration of electron vortex beams has opened up the new possibility of studying orbital angular momentum (OAM) in the interaction between electron beams and matter. To this aim, methods to analyze the OAM of an electron beam are fundamentally important and a necessary next step. We demonstrate the measurement of electron beam OAM through a variety of techniques. The use of forked holographic masks, diffraction from geometric apertures, and diffraction from a knife edge and the application of an astigmatic lens are all experimentally demonstrated. The viability and limitations of each are discussed with supporting numerical simulations. | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000332224100014 | Publication Date | 2014-02-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1050-2947;1094-1622; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.925 | Times cited | 42 | Open Access | |
| Notes | Vortex; FP7; Countatoms; ESTEEM2; esteem2jra3 ECASJO; | Approved | Most recent IF: 2.925; 2014 IF: 2.808 | ||
| Call Number | UA @ lucian @ c:irua:114577UA @ admin @ c:irua:114577 | Serial | 1972 | ||
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| Author | Van den Broek, W.; Rosenauer, A.; Van Aert, S.; Sijbers, J.; van Dyck, D. | ||||
| Title | A memory efficient method for fully three-dimensional object reconstruction with HAADF STEM | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 141 | Issue |
Pages | 22-31 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
| Abstract | The conventional approach to object reconstruction through electron tomography is to reduce the three-dimensional problem to a series of independent two-dimensional slice-by-slice reconstructions. However, at atomic resolution the image of a single atom extends over many such slices and incorporating this image as prior knowledge in tomography or depth sectioning therefore requires a fully three-dimensional treatment. Unfortunately, the size of the three-dimensional projection operator scales highly unfavorably with object size and readily exceeds the available computer memory. In this paper, it is shown that for incoherent image formation the memory requirement can be reduced to the fundamental lower limit of the object size, both for tomography and depth sectioning. Furthermore, it is shown through multislice calculations that high angle annular dark field scanning transmission electron microscopy can be sufficiently incoherent for the reconstruction of single element nanocrystals, but that dynamical diffraction effects can cause classification problems if more than one element is present. (C) 2014 Elsevier B.V. All rights reserved. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000335766600004 | Publication Date | 2014-03-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 6 | Open Access | |
| Notes | ResearchFoundationFlanders(FWO;G.0393.11; G.0064.10;andG.0374.13); European Union Seventh Frame- workProgramme [FP7/2007-2013]under Grant agreement no. 312483 (ESTEEM2).; esteem2jra2; esteem2jra4 | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:117650 | Serial | 1992 | ||
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| Author | De Schutter, B.; Devulder, W.; Schrauwen, A.; van Stiphout, K.; Perkisas, T.; Bals, S.; Vantomme, A.; Detavernier, C. | ||||
| Title | Phase formation in intermixed NiGe thin films : influence of Ge content and low-temperature nucleation of hexagonal nickel germanides | Type | A1 Journal article | ||
| Year | 2014 | Publication | Microelectronic engineering | Abbreviated Journal | Microelectron Eng |
| Volume | 120 | Issue |
Pages | 168-173 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In this study, we focus on phase formation in intermixed NiGe thin films as they represent a simplified model of the small intermixed interface layer that is believed to form upon deposition of Ni on Ge and where initial phase formation happens. A combinatorial sputter deposition technique was used to co-deposit a range of intermixed NiGe thin films with Ge concentrations varying between 0 and 50 at.%Ge in a single deposition on both Ge (100) and inert SiO2 substrates. In situ X-ray diffraction and transmission electron microscopy where used to study phase formation. In almost the entire composition range under investigation, crystalline phases where found to be present in the as-deposited films. Between 36 and 48 at.%Ge, high-temperature hexagonal nickel germanides were found to occur metastabily below 300 °C, both on SiO2 and Ge (100) substrates. For Ge concentrations in the range between 36 and 42 at.%, this hexagonal germanide phase was even found to be present at room temperature in the as-deposited films. The results obtained in this work could provide more insight in the phase sequence of a pure Ni film on Ge. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000336697300028 | Publication Date | 2013-09-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0167-9317; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.806 | Times cited | 9 | Open Access | Not_Open_Access |
| Notes | FWO project Nr. G076112N | Approved | Most recent IF: 1.806; 2014 IF: 1.197 | ||
| Call Number | UA @ lucian @ c:irua:116958 | Serial | 2584 | ||
| Permanent link to this record | |||||
| Author | Verbruggen, S.W.; Deng, S.; Kurttepeli, M.; Cott, D.J.; Vereecken, P.M.; Bals, S.; Martens, J.A.; Detavernier, C.; Lenaerts, S. | ||||
| Title | Photocatalytic acetaldehyde oxidation in air using spacious TiO2 films prepared by atomic layer deposition on supported carbonaceous sacrificial templates | Type | A1 Journal article | ||
| Year | 2014 | Publication | Applied catalysis : B : environmental | Abbreviated Journal | Appl Catal B-Environ |
| Volume | 160 | Issue |
Pages | 204-210 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | Supported carbon nanosheets and carbon nanotubes served as sacrificial templates for preparing spacious TiO2 photocatalytic thin films. Amorphous TiO2 was deposited conformally on the carbonaceous template material by atomic layer deposition (ALD). Upon calcination at 550 °C, the carbon template was oxidatively removed and the as-deposited continuous amorphous TiO2 layers transformed into interlinked anatase nanoparticles with an overall morphology commensurate to the original template structure. The effect of type of template, number of ALD cycles and gas residence time of pollutant on the photocatalytic activity, as well as the stability of the photocatalytic performance of these thin films was investigated. The TiO2 films exhibited excellent photocatalytic activity toward photocatalytic degradation of acetaldehyde in air as a model reaction for photocatalytic indoor air pollution abatement. Optimized films outperformed a reference film of commercial PC500. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000340687900024 | Publication Date | 2014-05-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0926-3373; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.446 | Times cited | 37 | Open Access | OpenAccess |
| Notes | 335078 Colouratom; Iap-Pai P7/05; Fwo; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); | Approved | Most recent IF: 9.446; 2014 IF: 7.435 | ||
| Call Number | UA @ lucian @ c:irua:117094 | Serial | 2608 | ||
| Permanent link to this record | |||||
| Author | Chen, D.; Goris, B.; Bleichrodt, F.; Heidari Mezerji, H.; Bals, S.; Batenburg, K.J.; de With, G.; Friedrich, H. | ||||
| Title | The properties of SIRT, TVM, and DART for 3D imaging of tubular domains in nanocomposite thin-films and sections | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 147 | Issue |
Pages | 137-148 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In electron tomography, the fidelity of the 3D reconstruction strongly depends on the employed reconstruction algorithm. In this paper, the properties of SIRT, TVM and DART reconstructions are studied with respect to having only a limited number of electrons available for imaging and applying different angular sampling schemes. A well-defined realistic model is generated, which consists of tubular domains within a matrix having slab-geometry. Subsequently, the electron tomography workflow is simulated from calculated tilt-series over experimental effects to reconstruction. In comparison with the model, the fidelity of each reconstruction method is evaluated qualitatively and quantitatively based on global and local edge profiles and resolvable distance between particles. Results show that the performance of all reconstruction methods declines with the total electron dose. Overall, SIRT algorithm is the most stable method and insensitive to changes in angular sampling. TVM algorithm yields significantly sharper edges in the reconstruction, but the edge positions are strongly influenced by the tilt scheme and the tubular objects become thinned. The DART algorithm markedly suppresses the elongation artifacts along the beam direction and moreover segments the reconstruction which can be considered a significant advantage for quantification. Finally, no advantage of TVM and DART to deal better with fewer projections was observed. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000343157400015 | Publication Date | 2014-08-19 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 42 | Open Access | OpenAccess |
| Notes | Fwo | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:119073 | Serial | 2729 | ||
| Permanent link to this record | |||||
| Author | Martinez, G.T.; Rosenauer, A.; de Backer, A.; Verbeeck, J.; Van Aert, S. | ||||
| Title | Quantitative composition determination at the atomic level using model-based high-angle annular dark field scanning transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 137 | Issue |
Pages | 12-19 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | High angle annular dark field scanning transmission electron microscopy (HAADF STEM) images provide sample information which is sensitive to the chemical composition. The image intensities indeed scale with the mean atomic number Z. To some extent, chemically different atomic column types can therefore be visually distinguished. However, in order to quantify the atomic column composition with high accuracy and precision, model-based methods are necessary. Therefore, an empirical incoherent parametric imaging model can be used of which the unknown parameters are determined using statistical parameter estimation theory (Van Aert et al., 2009, [1]). In this paper, it will be shown how this method can be combined with frozen lattice multislice simulations in order to evolve from a relative toward an absolute quantification of the composition of single atomic columns with mixed atom types. Furthermore, the validity of the model assumptions are explored and discussed. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000331092200003 | Publication Date | 2013-11-09 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 74 | Open Access | |
| Notes | FWO; FP7; ERC Countatoms; ESTEEM2; esteem2_ta | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:111579UA @ admin @ c:irua:111579 | Serial | 2749 | ||
| Permanent link to this record | |||||
| Author | Lao, M.; Eisterer, M.; Stadel, O.; Meledin, A.; Van Tendeloo, G. | ||||
| Title | The effect of Y2O3 and YFeO3 additions on the critical current density of YBCO coated conductors | Type | P1 Proceeding | ||
| Year | 2014 | Publication | 1-4 | Abbreviated Journal | |
| Volume | Issue |
Pages | |||
| Keywords | P1 Proceeding; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The pinning mechanism of MOCVD-grown YBCO coated conductors with Y2O3 precipitates was investigated by angle-resolved transport measurement of Je in a wide range of temperature and magnetic fields. Aside from the Y2O3 nanoprecipitates, a-axis grains and threading dislocation along the c-axis were found in the YBCO layer. The Y2O3 precipitates are less effective pinning centers at lower temperature. The tapes with precipitates show a higher anisotropy with larger J(c) at H parallel to ab than H parallel to c. This behavior was attributed to the preferred alignment of the nanoprecipitates along the ab-plane. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Iop publishing ltd | Place of Publication | Bristol | Editor | |
| Language | Wos | 000350818300068 | Publication Date | 2014-05-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | 507 | Series Issue | Edition | ||
| ISSN | 1742-6596; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 1 | Open Access | ||
| Notes | eurotapes | Approved | Most recent IF: NA | ||
| Call Number | UA @ lucian @ c:irua:125444 | Serial | 3577 | ||
| Permanent link to this record | |||||
| Author | Engelmann, Y.; Bogaerts, A.; Neyts, E.C. | ||||
| Title | Thermodynamics at the nanoscale : phase diagrams of nickel-carbon nanoclusters and equilibrium constants for face transitions | Type | A1 Journal article | ||
| Year | 2014 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
| Volume | 6 | Issue |
Pages | 11981-11987 | |
| Keywords | A1 Journal article; PLASMANT | ||||
| Abstract | Using reactive molecular dynamics simulations, the melting behavior of nickelcarbon nanoclusters is examined. The phase diagrams of icosahedral and Wulff polyhedron clusters are determined using both the Lindemann index and the potential energy. Formulae are derived for calculating the equilibrium constants and the solid and liquid fractions during a phase transition, allowing more rational determination of the melting temperature with respect to the arbitrary Lindemann value. These results give more insight into the properties of nickelcarbon nanoclusters in general and can specifically be very useful for a better understanding of the synthesis of carbon nanotubes using the catalytic chemical vapor deposition method. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos | 000343000800049 | Publication Date | 2014-07-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-3364;2040-3372; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.367 | Times cited | 20 | Open Access | |
| Notes | Approved | Most recent IF: 7.367; 2014 IF: 7.394 | |||
| Call Number | UA @ lucian @ c:irua:119408 | Serial | 3636 | ||
| Permanent link to this record | |||||
| Author | Adam, N.; Leroux, F.; Knapen, D.; Bals, S.; Blust, R. | ||||
| Title | The uptake of ZnO and CuO nanoparticles in the water-flea Daphnia magna under acute exposure scenarios | Type | A1 Journal article | ||
| Year | 2014 | Publication | Environmental pollution | Abbreviated Journal | Environ Pollut |
| Volume | 194 | Issue |
Pages | 130-137 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Veterinary physiology and biochemistry | ||||
| Abstract | In this study the uptake of ZnO and CuO nanoparticles by Daphnia magna was tested. Daphnids were exposed during 48 h to acute concentrations of the nanoparticles and corresponding metal salts. The Daphnia zinc and copper concentration was measured and the nanoparticles were localized using electron microscopy. The aggregation and dissolution in the medium was characterized. A fast dissolution of ZnO in the medium was observed, while most CuO formed large aggregates and only a small fraction dissolved. The Daphnia zinc concentration was comparable for the nanoparticles and salts. Contrarily, a much higher Daphnia copper concentration was observed in the CuO exposure, compared to the copper salt. CuO nanoparticles adsorbed onto the carapace and occurred in the gut but did not internalize in the tissues. The combined dissolution and uptake results indicate that the toxicity of both nanoparticle types was caused by metal ions dissolved from the particles in the medium. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | London | Editor | ||
| Language | Wos | 000342530800016 | Publication Date | 2014-08-07 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0269-7491; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 5.099 | Times cited | 45 | Open Access | Not_Open_Access |
| Notes | ; We would like to thank Valentine Mubiana and Steven Joosen (Sphere, UA) for performing the ICP-OES and ICP-MS measurements and Prof. Dr. Gustaaf Van Tendeloo for making the collaboration between the EMAT and Sphere group possible. Additional thanks go to the European Commission for funding this work through the project ENNSATOX (NMP4-SL-2009-229244). ; | Approved | Most recent IF: 5.099; 2014 IF: 4.143 | ||
| Call Number | UA @ lucian @ c:irua:118326 | Serial | 3823 | ||
| Permanent link to this record | |||||
| Author | Lamas, J.S.; Leroy, W.P.; Lu, Y.-G.; Verbeeck, J.; Van Tendeloo, G.; Depla, D. | ||||
| Title | Using the macroscopic scale to predict the nano-scale behavior of YSZ thin films | Type | A1 Journal article | ||
| Year | 2014 | Publication | Surface and coatings technology | Abbreviated Journal | Surf Coat Tech |
| Volume | 238 | Issue |
Pages | 45-50 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In this work, Yttria-stabilized zirconia (YSZ) thin films were deposited using dual reactive magnetron sputtering. By varying the deposition conditions, the film morphology and texture of the thin films are tuned and biaxial alignment is obtained. Studying the crystallographic and microstructural properties of the YSZ thin films, a tilted columnar growth was identified. This tilt is shown to be dependent on the compositional gradient of the sample. The variation of composition within a single YSZ column measured via STEM-EDX is demonstrated to be equal to the macroscopic variation on a full YSZ sample when deposited under the same deposition parameters. A simple stress model was developed to predict the tilt of the growing columns. The results indicate that this model not only determines the column bending of the growing film but also confirms that a macroscopic approach is sufficient to determine the compositional gradient in a single column of the YSZ thin films. (C) 2013 Elsevier B.V. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lausanne | Editor | ||
| Language | Wos | 000331028200005 | Publication Date | 2013-10-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0257-8972; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.589 | Times cited | 8 | Open Access | |
| Notes | 246791 Countatoms; 278510 Vortex;Nmp3-La-2010-246102 Ifox; 312483 Esteem2; esteem2jra3 ECASJO; | Approved | Most recent IF: 2.589; 2014 IF: 1.998 | ||
| Call Number | UA @ lucian @ c:irua:115765 | Serial | 3827 | ||
| Permanent link to this record | |||||
| Author | van Oers, C.J.; Kurttepeli, M.; Mertens, M.; Bals, S.; Meynen, V.; Cool, P. | ||||
| Title | Zeolite \beta nanoparticles based bimodal structures : mechanism and tuning of the porosity and zeolitic properties | Type | A1 Journal article | ||
| Year | 2014 | Publication | Microporous and mesoporous materials: zeolites, clays, carbons and related materials | Abbreviated Journal | Micropor Mesopor Mat |
| Volume | 185 | Issue |
Pages | 204-212 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
| Abstract | Despite great efforts in the research area of zeolite nanoparticles and their use in the synthesis of bimodal materials, still little is known about the impact of the synthesis conditions of the zeolite nanoparticles on its own characteristics, and on the properties and the formation mechanism of the final bimodal materials. A zeolite β nanoparticles solution is applied in a mesotemplate-free synthesis method, and the influence of the hydrothermal ageing temperature of the nanoparticles solution on both the zeolitic and porosity characteristics of the final bimodal material has been studied. Transmission electron microscopy in combination with 3-dimensional reconstructions obtained by electron tomography revealed that the zeolite β nanoparticles are connected by neck-like structures, thus creating a wormhole-like mesoporous material. Considering the zeolitic properties, a clear threshold is observed in the synthesis temperature series at 413 K. Below and at this threshold, the biporous materials show no apparent zeolitic characteristics, although these materials exhibit a more condensed and uniform SiOSi network in comparison to Al-MCF. Synthesis temperatures above the threshold lead to bimodal structures with defined zeolitic properties. Moreover, the dimensions of the nanoparticles are studied by TEM, revealing an increasing particle size with increasing temperature under the threshold of 413 K, which is in agreement with a sol-mechanism. This mechanism is disturbed after the threshold due to the start of the crystallisation process. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000330930400025 | Publication Date | 2013-11-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1387-1811; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.615 | Times cited | 10 | Open Access | OpenAccess |
| Notes | 262348 Esmi | Approved | Most recent IF: 3.615; 2014 IF: 3.453 | ||
| Call Number | UA @ lucian @ c:irua:112501 | Serial | 3930 | ||
| Permanent link to this record | |||||
| Author | Kalesaki, E.; Boneschanscher, M.P.; Geuchies, J.J.; Delerue, C.; Morais Smith, C.; Evers, W.H.; Allan, G.; Altantzis, T.; Bals, S.; Vanmaekelbergh, D. | ||||
| Title | Preparation and study of 2-D semiconductors with Dirac type bands due to the honeycomb nanogeometry | Type | P1 Proceeding | ||
| Year | 2014 | Publication | Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Proceedings of SPIE | Abbreviated Journal | |
| Volume | 8981 | Issue |
Pages | 898107-898107 | |
| Keywords | P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The interest in 2-dimensional systems with a honeycomb lattice and related Dirac-type electronic bands has exceeded the prototype graphene1. Currently, 2-dimensional atomic2,3 and nanoscale4-8 systems are extensively investigated in the search for materials with novel electronic properties that can be tailored by geometry. The immediate question that arises is how to fabricate 2-D semiconductors that have a honeycomb nanogeometry, and as a consequence of that, display a Dirac-type band structure? Here, we show that atomically coherent honeycomb superlattices of rocksalt (PbSe, PbTe) and zincblende (CdSe, CdTe) semiconductors can be obtained by nanocrystal self-assembly and facet-to-facet atomic bonding, and subsequent cation exchange. We present a extended structural analysis of atomically coherent 2-D honeycomb structures that were recently obtained with self-assembly and facet-to-facet bonding9. We show that this process may in principle lead to three different types of honeycomb structures, one with a graphene type-, and two others with a silicene-type structure. Using TEM, electron diffraction, STM and GISAXS it is convincingly shown that the structures are from the silicene-type. In the second part of this work, we describe the electronic structure of graphene-type and silicene type honeycomb semiconductors. We present the results of advanced electronic structure calculations using the sp3d5s* atomistic tight-binding method10. For simplicity, we focus on semiconductors with a simple and single conduction band for the native bulk semiconductor. When the 3-D geometry is changed into 2-D honeycomb, a conduction band structure transformation to two types of Dirac cones, one for S- and one for P-orbitals, is observed. The width of the bands depends on the honeycomb period and the coupling between the nanocrystals. Furthermore, there is a dispersionless P-orbital band, which also forms a landmark of the honeycomb structure. The effects of considerable intrinsic spin-orbit coupling are briefly considered. For heavy-element compounds such as CdTe, strong intrinsic spin-‐orbit coupling opens a non-trivial gap at the P-orbital Dirac point, leading to a quantum Spin Hall effect10-12. Our work shows that well known semiconductor crystals, known for centuries, can lead to systems with entirely new electronic properties, by the simple action of nanogeometry. It can be foreseen that such structures will play a key role in future opto-electronic applications, provided that they can be fabricated in a straightforward way. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000336040600004 | Publication Date | 2014-03-07 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
| Impact Factor | Times cited | 2 | Open Access | OpenAccess | |
| Notes | This work has been supported by funding of the French National Research Agency [ANR, (ANR-‐09-‐BLAN-‐0421-‐01)], NWO and the Dutch organization FOM [Programs “Control over Functional Nanoparticle Solids” (FNPS) and “Designing Dirac Carriers in Semiconductors” | Approved | Most recent IF: NA | ||
| Call Number | c:irua:131912 | Serial | 4039 | ||
| Permanent link to this record | |||||
| Author | van den Broek, B.; Houssa, M.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. | ||||
| Title | Two-dimensional hexagonal tin : ab initio geometry, stability, electronic structure and functionalization | Type | A1 Journal article | ||
| Year | 2014 | Publication | 2D materials | Abbreviated Journal | 2D Mater |
| Volume | 1 | Issue |
Pages | 021004 | |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | We study the structural, mechanical and electronic properties of the two-dimensional (2D) allotrope of tin: tinene/stanene using first-principles calculation within density functional theory, implemented in a set of computer codes. Continuing the trend of the group-IV 2D materials graphene, silicene and germanene; tinene is predicted to have a honeycomb lattice with lattice parameter of a(0) = 4.62 angstrom and a buckling of d(0) = 0.92 angstrom. The electronic dispersion shows a Dirac cone with zero gap at the Fermi energy and a Fermi velocity of v(F) = 0.97 x 10(6) m s(-1); including spin-orbit coupling yields a bandgap of 0.10 eV. The monolayer is thermally stable up to 700 K, as indicated by first-principles molecular dynamics, and has a phonon dispersion without imaginary frequencies. We explore applied electric field and applied strain as functionalization mechanisms. Combining these two mechanisms allows for an induced bandgap up to 0.21 eV, whilst retaining the linear dispersion, albeit with degraded electronic transport parameters. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | IOP Publishing | Place of Publication | Bristol | Editor | |
| Language | Wos | 000353650400004 | Publication Date | 2014-08-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2053-1583 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.937 | Times cited | 58 | Open Access | |
| Notes | Approved | Most recent IF: 6.937; 2014 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:134432 | Serial | 4530 | ||
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| Author | N. Gauquelin, D. G. Hawthorn, G. A. Sawatzky, R. X. Liang, D. A. Bonn, W. N. Hardy & G.A. Botton | ||||
| Title | Atomic scale real-space mapping of holes in YBa2Cu3O6+δ | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Nature Communications | Abbreviated Journal | |
| Volume | 5 | Issue |
Pages | 4275 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The high-temperature superconductor YBa2Cu3O6+δ consists of two main structural units—a bilayer of CuO2 planes that are central to superconductivity and a CuO2+δ chain layer. Although the functional role of the planes and chains has long been established, most probes integrate over both, which makes it difficult to distinguish the contribution of each. Here we use electron energy loss spectroscopy to directly resolve the plane and chain contributions to the electronic structure in YBa2Cu3O6 and YBa2Cu3O7. We directly probe the charge transfer of holes from the chains to the planes as a function of oxygen content, and show that the change in orbital occupation of Cu is large in the chain layer but modest in CuO2 planes, with holes in the planes doped primarily into the O 2p states. These results provide direct insight into the local electronic structure and charge transfers in this important high-temperature superconductor. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000340615100002 | Publication Date | 2014-07-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | |||
| Impact Factor | Times cited | 22 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4542 | ||
| Permanent link to this record | |||||
| Author | N. Gauquelin, E. Benckiser, M. K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H.-U. Habermeier, U. Kaiser, B. Keimer, and G. A. Botton | ||||
| Title | Atomically resolved EELS mapping of the interfacial structure of epitaxially strained LaNiO3/LaAlO3 superlattices | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Physical Review B | Abbreviated Journal | |
| Volume | 90 | Issue |
Pages | 195140 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The interfacial atomic structure of a metallic LaNiO3/LaAlO3 superlattice grown on a LaSrAlO4 substrate was investigated using a combination of atomically resolved electron energy loss spectroscopy (EELS) at the Al K, Al L2,3, Sr L2,3, Ni L2,3, La M4,5, and O K edges as well as hybridization mapping of selected features of the O K-edge fine structure.We observe an additional La1−xSrxAl1−yNiyO3 layer at the substrate-superlattice interface, possibly linked to diffusion of Al and Sr into the growing film or a surface reconstruction due to Sr segregation. The roughness of the LaNiO3/LaAlO3 interfaces is found to be on average around one pseudocubic unit cell. The O K-edge EELS spectra revealed reduced spectral weight of the prepeak derived from Ni-O hybridized states in the LaNiO3 layers. We rule out oxygen nonstoichiometry of the LaNiO3 layers and discuss changes in the Ni-O hybridization due to heterostructuring as possible origin. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000345467000003 | Publication Date | 2014-11-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | |||
| Impact Factor | Times cited | 17 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4544 | ||
| Permanent link to this record | |||||
| Author | M. K. Kinyanjui, N. Gauquelin, E. Benckiser, H. –U. Habermeier, B. Keimer, U. Kaiser and G.A. Botton | ||||
| Title | Local lattice distortion and anisotropic modulation in Epitaxially Strained LaNiO3/LaAlO3 hetero-structures | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Applied Physics Letters | Abbreviated Journal | |
| Volume | 104 | Issue |
Pages | 221909 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | Using a complementary combination of x-ray diffraction and atomically resolved imaging we investigated the lattice structure of epitaxial LaNiO3/LaAlO3 superlattices grown on a compressive-strain inducing LaSrAlO4 (001) substrate. A refinement of the structure obtained from the x-ray data revealed the monoclinic I 2/c 1 1 space group. The (Ni/Al)O6 octahedral rotation angle perpendicular to the superlattice plane is enhanced, and the one parallel to the plane is reduced with respect to the corresponding bulk values. High-angle annular dark field imaging was used to determine the lattice parameters within the superlattice unit cell. High-resolution electron microscopy images of the oxygen atoms are consistent with the x-ray results. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000337161700029 | Publication Date | 2014-06-07 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | |||
| Impact Factor | Times cited | 22 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4545 | ||
| Permanent link to this record | |||||
| Author | Saniz, R.; Vercauteren, S.; Lamoen, D.; Partoens, B.; Barbiellini, B. | ||||
| Title | Accurate description of the van der Waals interaction of an electron-positron pair with the surface of a topological insulator | Type | P1 Proceeding | ||
| Year | 2014 | Publication | Journal of physics : conference series | Abbreviated Journal | |
| Volume | 505 | Issue |
Pages | 012002 | |
| Keywords | P1 Proceeding; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | Positrons can be trapped in localized states at the surface of a material, and thus quite selectively interact with core or valence surface electrons. Hence, advanced surface positron spectroscopy techniques can present the ideal tools to study a topological insulator, where surface states play a fundamental role. We analyze the problem of a positron at a TI surface, assuming that it is a weakly physisorbed positronium (Ps) atom. To determine if the surface of interest in a material can sustain such a physisorption, an accurate description of the underlying van der Waals (vdW) interaction is essential. We have developed a first-principles parameterfree method, based on the density functional theory, to extract key parameters determining the vdW interaction potential between a Ps atom and the surface of a given material. The method has been successfully applied to quartz and preliminary results on Bi2Te2Se indicate the existence of a positron surface state. We discuss the robustness of our predictions versus the most relevant approximations involved in our approach. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Bristol | Editor | ||
| Language | Wos | 000338216500002 | Publication Date | 2014-04-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1742-6588;1742-6596; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 2 | Open Access | ||
| Notes | ; We thank A. Weiss for very useful conversations. We acknowledge financial support from FWO-Vlaanderen (projectG.0150.13). This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), adivision of the Flemish Supercomputer Center (VSC), funded by the Hercules foundation and the Flemish Government (EWI Department). B. B. is supported by DOE grants Nos. DE-FG02-07ER46352 and DE-AC02-05CH11231 for theory support at ALS, Berkeley, and a NERSC computer time allocation. ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ lucian @ c:irua:118264 | Serial | 46 | ||
| Permanent link to this record | |||||
| Author | Lobato, I. | ||||
| Title | Accurate modeling of high angle electron scattering | Type | Doctoral thesis | ||
| Year | 2014 | Publication | Abbreviated Journal | ||
| Volume | Issue |
Pages | |||
| Keywords | Doctoral thesis; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Antwerpen | Editor | ||
| Language | Wos | Publication Date | 0000-00-00 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record | ||
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:120593 | Serial | 50 | ||
| Permanent link to this record | |||||
| Author | Goris, B. | ||||
| Title | Advanced electron tomography : 3 dimensional structural characterisation of nanomaterials down to the atomic scale | Type | Doctoral thesis | ||
| Year | 2014 | Publication | Abbreviated Journal | ||
| Volume | Issue |
Pages | |||
| Keywords | Doctoral thesis; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Antwerpen | Editor | ||
| Language | Wos | Publication Date | 0000-00-00 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record | ||
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:119017 | Serial | 71 | ||
| Permanent link to this record | |||||