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Author |
Wang, Y.; Sentosun, K.; Li, A.; Coronado-Puchau, M.; Sánchez-Iglesias, A.; Li, S.; Su, X.; Bals, S.; Liz-Marzán, L.M. |
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Title |
Engineering Structural Diversity in Gold Nanocrystals by Ligand-Mediated Interface Control |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
27 |
Issue |
27 |
Pages |
8032-8040 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Surface and interface control is fundamentally important for crystal growth engineering, catalysis, surface enhanced spectroscopies, and self-assembly, among other processes and applications. Understanding the role of ligands in regulating surface properties of plasmonic metal nanocrystals during growth has received considerable attention. However, the underlying mechanisms and the diverse functionalities of ligands are yet to be fully addressed. In this contribution,
we report a systematic study of ligand-mediated interface control in seeded growth of gold nanocrystals, leading to diverse and exotic nanostructures with an improved surface enhanced Raman scattering (SERS) activity. Three dimensional transmission electron microscopy (3D TEM) revealed an intriguing gold shell growth process mediated by the bifunctional ligand 1,4-benzenedithiol (BDT), which leads to a unique crystal growth mechanism as compared to other ligands, and subsequently to the concept of interfacial energy control mechanism. Volmer-Weber growth mode was proposed to be responsible for BDT-mediated seeded growth, favoring the strongest interfacial energy and generating an asymmetric island growth pathway with internal crevices/gaps. This additionally favors incorporation of BDT at the plasmonic nanogaps, thereby generating strong SERS activity with a maximum efficiency for a core-semishell configuration obtained along seeded growth. Numerical modeling was used to explain this observation. Interestingly, the same strategy can be used to engineer the structural diversity of this system, by using gold nanoparticle seeds with various sizes and shapes, and varying the [Au3+]/[Au0] ratio. This rendered a series of diverse and exotic plasmonic nanohybrids such as semishell-coated gold nanorods, with embedded Raman-active tags and Janus surface with distinct surface functionalities.
These would greatly enrich the plasmonic nanostructure toolbox for various studies and applications such as anisotropic nanocrystal engineering, SERS, and high-resolution Raman bioimaging or nanoantenna devices. |
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Wos  |
000366223200023 |
Publication Date |
2015-10-09 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0897-4756;1520-5002; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
18 |
Open Access |
OpenAccess |
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Notes |
The authors thank Bart Goris for his help with electron tomography. This work was funded by the European Commission (Grant #310445-2, SAVVY). The authors acknowledge financial support from European Research Council (ERC Advanced Grant # 267867- PLASMAQUO, ERC Starting Grant #335078-COLOURATOMS). The authors also appreciate financial support from the European Union under the Seventh Framework Program (Integrated Infrastructure Initiative N. 262348 European Soft Matter Infrastructure, ESMI). Wang Y. and Su X. would like to acknowledge the Agency for Science, Technology and Research (A*STAR), Singapore, for the financial support under the Grant JCO 14302FG096. M. C.-P. acknowledges an FPU scholarship from the Spanish Ministry of Education, Culture and Sports.; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 9.466; 2015 IF: 8.354 |
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Call Number |
c:irua:129598 c:irua:129598 |
Serial |
3972 |
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Author |
Martinez, G.T.; Jones, L.; de Backer, A.; Béché, A.; Verbeeck, J.; Van Aert, S.; Nellist, P.D. |
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Title |
Quantitative STEM normalisation : the importance of the electron flux |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
159 |
Issue |
159 |
Pages |
46-58 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Annular dark-field (ADF) scanning transmission electron microscopy (STEM) has become widely used in quantitative studies based on the opportunity to directly compare experimental and simulated images. This comparison merely requires the experimental data to be normalised and expressed in units of fractional beam-current. However, inhomogeneities in the response of electron detectors can complicate this normalisation. The quantification procedure becomes both experiment and instrument specific, requiring new simulations for the particular response of each instrument's detector, and for every camera-length used. This not only impedes the comparison between different instruments and research groups, but can also be computationally very time consuming. Furthermore, not all image simulation methods allow for the inclusion of an inhomogeneous detector response. In this work, we propose an alternative method for normalising experimental data in order to compare these with simulations that consider a homogeneous detector response. To achieve this, we determine the electron flux distribution reaching the detector by means of a camera-length series or a so-called atomic column cross-section averaged convergent beam electron diffraction (XSACBED) pattern. The result is then used to determine the relative weighting of the detector response. Here we show that the results obtained by this new electron flux weighted (EFW) method are comparable to the currently used method, while considerably simplifying the needed simulation libraries. The proposed method also allows one to obtain a metric that describes the quality of the detector response in comparison with the ideal detector response. |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000366220000006 |
Publication Date |
2015-08-01 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
27 |
Open Access |
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Notes |
246791 Countatoms; 278510 Vortex; 312483 Esteem2; Fwo G036815; G036915; G037413; G004413; esteem2ta ECASJO; |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
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Call Number |
c:irua:127293 c:irua:127293UA @ admin @ c:irua:127293 |
Serial |
2762 |
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Author |
Molina-Luna, L.; Duerrschnabel, M.; Turner, S.; Erbe, M.; Martinez, G.T.; Van Aert, S.; Holzapfel, B.; Van Tendeloo, G. |
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Title |
Atomic and electronic structures of BaHfO3-doped TFA-MOD-derived YBa2Cu3O7−δthin films |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
28 |
Issue |
28 |
Pages |
115009 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Tailoring the properties of oxide-based nanocomposites is of great importance for a wide range of materials relevant for energy technology. YBa2Cu3O7−δ (YBCO) superconducting thin films containing nanosized BaHfO3 (BHO) particles yield a significant improvement of the magnetic flux pinning properties and a reduced anisotropy of the critical current density. These films were prepared by chemical solution deposition (CSD) on (100) SrTiO3 (STO) substrates yielding critical current densities up to 3.6 MA cm−2 at 77 K and self-field. Transport in-field J c measurements demonstrated a high pinning force maximum of around 6 GN/m3 for a sample annealed at T = 760 °C that has a doping of 12 mol% of BHO. This sample was investigated by scanning transmission electron microscopy (STEM) in combination with electron energy-loss spectroscopy (EELS) yielding strain and spectral maps. Spherical BHO nanoparticles of 15 nm in size were found in the matrix, whereas the particles at the interface were flat. A 2 nm diffusion layer containing Ti was found at the YBCO (BHO)/STO interface. Local lattice deformation mapping at the atomic scale revealed crystal defects induced by the presence of both sorts of BHO nanoparticles, which can act as pinning centers for magnetic flux lines. Two types of local lattice defects were identified and imaged: (i) misfit edge dislocations and (ii) Ba-Cu-Cu-Ba stacking faults (Y-248 intergrowths). The local electronic structure and charge transfer were probed by high energy resolution monochromated electron energy-loss spectroscopy. This technique made it possible to distinguish superconducting from non-superconducting areas in nanocomposite samples with atomic resolution in real space, allowing the identification of local pinning sites on the order of the coherence length of YBCO (~1.5 nm) and the determination of 0.25 nm dislocation cores. |
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Wos |
000366193000018 |
Publication Date |
2015-09-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-2048;1361-6668; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.878 |
Times cited |
4 |
Open Access |
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Notes |
The authors thank financial support from the European Union under the Framework 6 program as a contract for an Integrated Infrastructure Initiative (References No. 026019 ESTEEM) and by the EUFP6 Research Project “NanoEngineered Superconductors for Power Applications” NESPA no. MRTN-CT-2006-035619. This work was supported by funding from the European Research Council under the Seventh Framework Programme (FP7). L.M.L, S.T. and G.V.T acknowledge ERC grant N°246791 – COUNTATOMS and funding under a contract for an Integrated Infrastructure Initiative, Reference No. 312483- ESTEEM2, as well as the EC project EUROTAPES. G.T.M. and S.V.A acknowledge financial support from the Fund for Scientific Research-Flanders (Reference G.0064.10N and G.0393.11N). M.D. acknowledges financial support from the LOEWE research cluster RESPONSE (Hessen, Germany). M.E. has received funding from the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement n° NMP-LA-2012-280432.; esteem2jra2; esteem2jra3 |
Approved |
Most recent IF: 2.878; 2015 IF: 2.325 |
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Call Number |
c:irua:129199 c:irua:129199 |
Serial |
3942 |
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Author |
Erbe, M.; Hänisch, J.; Hühne, R.; Freudenberg, T.; Kirchner, A.; Molina-Luna, L.; Damm, C.; Van Tendeloo, G.; Kaskel, S.; Schultz, L.; Holzapfel, B. |
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Title |
BaHfO3artificial pinning centres in TFA-MOD-derived YBCO and GdBCO thin films |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
28 |
Issue |
28 |
Pages |
114002 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Chemical solution deposition (CSD) is a promising way to realize REBa2Cu3O7−x (REBCO;RE = rare earth (here Y, Gd))-coated conductors with high performance in applied magnetic fields. However, the preparation process contains numerous parameters which need to be tuned to achieve high-quality films. Therefore, we investigated the growth of REBCO thin films containing nanometre-scale BaHfO3 (BHO) particles as pinning centres for magnetic flux lines, with emphasis on the influence of crystallization temperature and substrate on the microstructure and superconductivity. Conductivity, microscopy and x-ray investigations show an enhanced performance of BHO nano-composites in comparison to pristine REBCO. Further, those measurements reveal the superiority of GdBCO to YBCO—e.g. by inductive critical current densities, Jc, at self-field and 77 K. YBCO is outperformed by more than 1 MA cm−2 with Jc values of up to 5.0 MA cm−2 for 265 nm thick layers of GdBCO(BHO) on lanthanum aluminate. Transport in-field Jc measurements demonstrate high pinning force maxima of around 4 GN m−3 for YBCO(BHO) and GdBCO(BHO). However, the irreversibility fields are appreciably higher for GdBCO. The critical temperature was not significantly reduced upon BHO addition to both YBCO and GdBCO, indicating a low tendency for Hf diffusion into the REBCO matrix. Angular-dependent Jc measurements show a reduction of the anisotropy in the same order of magnitude for both REBCO compounds. Theoretical models suggest that more than one sort of pinning centre is active in all CSD films. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Wos |
000366193000003 |
Publication Date |
2015-09-25 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-2048;1361-6668; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.878 |
Times cited |
36 |
Open Access |
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Notes |
Experimental work was mainly done at IFW Dresden. We thank Juliane Scheiter and Dr Jens Ingolf Mönch of IFW Dresden for technical assistance. The research leading to these results received funding from EUROTAPES, a collaborative project funded by the European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement no. NMP-LA-2012-280 432. L Molina-Luna and G Van Tendeloo acknowledge funding from the European Research Council (ERC grant nr. 24 691-COUNTATOMS). |
Approved |
Most recent IF: 2.878; 2015 IF: 2.325 |
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Call Number |
c:irua:129200 |
Serial |
3941 |
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Author |
Tirez, K.; Vanhoof, C.; Bronders, J.; Seuntjens, P.; Bleux, N.; Berghmans, P.; De Brucker, N.; Vanhaecke, F. |
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Title |
Do ICP-MS based methods fulfill the EU monitoring requirements for the determination of elements in our environment? |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Environmental science : processes & impacts |
Abbreviated Journal |
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Volume |
17 |
Issue |
12 |
Pages |
2034-2050 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Undoubtedly, the most important advance in the environmental regulatory monitoring of elements of the last decade is the widespread introduction of ICP-mass spectrometry (ICP-MS) due to standards developed by the European Committee for Standardization. The versatility of ICP-MS units as a tool for the determination of major, minor and trace elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sn, Ti, V and Zn) in surface water, groundwater, river sediment, topsoil, subsoil, fine particulates and atmospheric deposition is illustrated in this paper. Ranges of background concentrations for major, minor and trace elements obtained from a regional case study (Flanders, Belgium) are summarized for all of these environmental compartments and discussed in the context of a harmonized implementation of European regulatory monitoring requirements. The results were derived from monitoring programs in support of EU environmental quality directives and were based on a selection of (non-polluted) background locations. Because of the availability of ICP-MS instruments nowadays, it can be argued that the main hindrance for meeting the European environmental monitoring requirements is no longer the technical feasibility of analysis at these concentration levels, but rather (i) potential contamination during sampling and analysis, (ii) too limited implementation of quality control programs, validating the routinely applied methods (including sampling and low level verification) and (iii) lack of harmonization in reporting of the chemical environmental status between the individual member states. |
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Wos |
000365915600005 |
Publication Date |
2015-10-06 |
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Abbreviated Series Title |
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Edition |
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ISSN |
2050-7887; 2050-7895 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:130316 |
Serial |
7821 |
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Author |
Bogaerts, A.; Kozak, T.; van Laer, K.; Snoeckx, R. |
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Title |
Plasma-based conversion of CO2: current status and future challenges |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Faraday discussions |
Abbreviated Journal |
Faraday Discuss |
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Volume |
183 |
Issue |
183 |
Pages |
217-232 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
This paper discusses our recent results on plasma-based CO2 conversion, obtained by a combination of experiments and modeling, for a dielectric barrier discharge (DBD), a microwave plasma and a packed bed DBD reactor. The results illustrate that plasma technology is quite promising for CO2 conversion, but more research is needed to better understand the underlying mechanisms and to further improve the capabilities. |
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Address |
Research Group PLASMANT, University of Antwerp, Department of Chemistry, Universiteitsplein 1, Antwerp, Belgium. annemie.bogaerts@uantwerpen.be |
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English |
Wos |
000365914900013 |
Publication Date |
2015-06-29 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1359-6640 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.588 |
Times cited |
89 |
Open Access |
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Notes |
We thank R. Aerts and W. van Gaens for setting up the experimental systems and for the interesting results obtained during their PhD study in our group. We also acknowledge nancial support from the IAP/7 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’ by the Belgian Federal Office for Science Policy (BELSPO), the Fund for Scientic Research Flanders (FWO) and the EU-FP7-ITN network “RAPID”. |
Approved |
Most recent IF: 3.588; 2015 IF: 4.606 |
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Call Number |
c:irua:130318 |
Serial |
3983 |
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Author |
de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. |
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Title |
Comparison of the electronic structure of amorphous versus crystalline indium gallium zinc oxide semiconductor : structure, tail states and strain effects |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
48 |
Issue |
48 |
Pages |
435104 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
We study the evolution of the structural and electronic properties of crystalline indium gallium zinc oxide (IGZO) upon amorphization by first-principles calculation. The bottom of the conduction band (BCB) is found to be constituted of a pseudo-band of molecular orbitals that resonate at the same energy on different atomic sites. They display a bonding character between the s orbitals of the metal sites and an anti-bonding character arising from the interaction between the oxygen and metal s orbitals. The energy level of the BCB shifts upon breaking of the crystal symmetry during the amorphization process, which may be attributed to the reduction of the coordination of the cationic centers. The top of the valence band (TVB) is constructed from anti-bonding oxygen p orbitals. In the amorphous state, they have random orientation, in contrast to the crystalline state. This results in the appearance of localized tail states in the forbidden gap above the TVB. Zinc is found to play a predominant role in the generation of these tail states, while gallium hinders their formation. Last, we study the dependence of the fundamental gap and effective mass of IGZO on mechanical strain. The variation of the gap under strain arises from the enhancement of the anti-bonding interaction in the BCB due to the modification of the length of the oxygen-metal bonds and/or to a variation of the cation coordination. This effect is less pronounced for the amorphous material compared to the crystalline material, making amorphous IGZO a semiconductor of choice for flexible electronics. Finally, the effective mass is found to increase upon strain, in contrast to regular materials. This counterintuitive variation is due to the reduction of the electrostatic shielding of the cationic centers by oxygen, leading to an increase of the overlaps between the metal orbitals at the origin of the delocalization of the BCB. For the range of strain typically met in flexible electronics, the induced variation in the effective mass is found to be negligible (less than 1%). |
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Corporate Author |
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Publisher |
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Place of Publication |
London |
Editor |
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Wos |
000365876300012 |
Publication Date |
2015-09-30 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
23 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2015 IF: 2.721 |
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Call Number |
UA @ lucian @ c:irua:130277 |
Serial |
4153 |
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Author |
Forsh, E.A.; Abakumov, A.M.; Zaytsev, V.B.; Konstantinova, E.A.; Forsh, P.A.; Rumyantseva, M.N.; Gaskov, A.M.; Kashkarov, P.K. |
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Title |
Optical and photoelectrical properties of nanocrystalline indium oxide with small grains |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
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Volume |
595 |
Issue |
595 |
Pages |
25-31 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Optical properties, spectral dependence of photoconductivity and photoconductivity decay in nanocrystalline indium oxide In2O3 are studied. A number of nanostructured In2O3 samples with various nanocrystals size are prepared by sol-gel method and characterized using various techniques. The mean nanocrystals size varies from 7 to 8 nm to 39-41 nm depending on the preparation conditions. Structural characterization of the In2O3 samples is performed by means of transmission electron microscopy and X-ray powder diffraction. The combined analysis of ultraviolet-visible absorption spectroscopy and diffuse reflectance spectroscopy shows that nanostructuring leads to the change in optical band gap: optical band gap of the In2O3 samples (with an average nanocrystal size from 7 to 41 nm) is equal to 2.8 eV. We find out the correlation between spectral dependence of photoconductivity and optical properties of nanocrystalline In2O3: sharp increase in photoconductivity was observed to begin at 2.8 eV that is equal to the optical bandgap in the In2O3 samples, and reached its maximum at 3.2-3.3 eV. The combined analysis of the slow photoconductivity decay in air, vacuum and argon, that was accurately fitted by a stretched-exponential function, and electron paramagnetic resonance (EPR) measurements shows that the kinetics of photoconductivity decay is strongly depended on the presence of oxygen molecules in the ambient of In2O3 nanocrystals. There is the quantitative correlation between EPR and photoconductivity data. Based on the obtained data we propose the model clearing up the phenomenon of permanent photoconductivity decay in nanocrystalline In2O3. (C) 2015 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000365812400005 |
Publication Date |
2015-10-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0040-6090 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.879 |
Times cited |
18 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.879; 2015 IF: 1.759 |
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Call Number |
UA @ lucian @ c:irua:130254 |
Serial |
4219 |
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Author |
Matthai, C.C.; Lamoen, D.; March, N.H. |
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Title |
Melting temperatures and possible precursor plastic phases of CCl4and GeI4as a function of pressure |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Physics and chemistry of liquids |
Abbreviated Journal |
Phys Chem Liq |
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Volume |
54 |
Issue |
54 |
Pages |
130-134 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The motivation for the present study is to be found in the recent experiments of Fuchizaki and Hamaya on GeI4. They observed a rapid increase in the melting temperature Tm in going from atmospheric pressure to p ~ 2.6 GPa. Tm was found to be largely independent of pressure above this value. In this paper, heuristic arguments are presented to support the idea that until some critical pressure, a crystalline phase of SnI4, CCl4 and GeI4 molecular solids melts into a low density liquid. However, at this critical pressure, a phase boundary intersects Tm(p), separating a low density liquid phase from a high density liquid. The new phase boundary is between the crystal and an amorphous molecular solid with increasing polymerisation as the pressure is increased. |
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Wos |
000365724100012 |
Publication Date |
2015-07-30 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9104 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.145 |
Times cited |
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Open Access |
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Notes |
NHM wishes to thank Professors D. Lamoen and C. Van Alsenoy for making possible the continuing affiliation of |
Approved |
Most recent IF: 1.145 |
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Call Number |
c:irua:130190 |
Serial |
4029 |
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Author |
Cagno, S.; Cosyns, P.; Ceglia, A.; Nys, K.; Janssens, K. |
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Title |
The use of vitrum obsianum in the Roman Empire: some new insights and future prospects |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Periodico di mineralogia |
Abbreviated Journal |
Period Mineral |
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Volume |
84 |
Issue |
3a |
Pages |
465-482 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The research on the use of obsidian in the Mediterranean is extensive but concerns almost exclusively volcanic glass from prehistoric and Bronze Age contexts. The consumption of obsidian during the Roman imperial period, however, has only occasionally received attention. Never a comprehensive account on what the Romans made in vitrum obsianum has been set up, nor have the sources exploited by them been examined. This paper provides a concise overview of the current knowledge on obsidian during the Roman imperial period and offers an introductory outline on potential research. The ancient writers inform us about the use of volcanic glass to create exclusive vessels, gemstones, mirrors and sculpture, but also about the creation of black appearing man-made glass initiated as a cheap and easier workable substitute of obsidian. The archaeological data on the other hand propose a more complex story with the occurrence of obsidian chunks in early Roman secondary glass workshops, and the bulky use of obsidian in late Antiquity to produce tesserae for the creation of wall and vault mosaics. Because it is extremely difficult to visually distinguish natural obsidian from man-made glass imitations we present in this paper data collected by means of non-destructive chemico-physical analyses SEM-EDX, portable X-ray fluorescence (p-XRF) and Raman spectroscopy to easily distinguish man-made glass from natural obsidian. In particular the use of portable instruments makes possible in situ analysis of objects in archaeological depots or museum collections to help defining distribution networks to better understand the shifting consumption patterns in Antiquity. |
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Wos |
000365632500007 |
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Series Volume |
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Edition |
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ISSN |
0369-8963 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
0.883 |
Times cited |
2 |
Open Access |
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Notes |
; Our sincere gratitude goes to Cecile Evers and Natacha Masar to have granted permission for studying and analysing various obsidian artefacts within the collections of the Royal Museums of Art and History, Brussels (Belgium). We are also very grateful to Roald Doctor, Daniele Foy and Laudine Robin, respectively for having provided the material from Carthage, for the Sidi Jdidi tessera and Lyon. Our appreciation also goes to Ian Freestone and Andrew Meek respectively for having worked out and provided the internal report on the horse foreleg in the British Museum. Finally we wish to thank Jennifer Price, Maria Grazia Diani respectively for the information on the Stanwick fragment and the piece in the Pogliaghi-Varesse collection. This research was supported by the Hercules Foundation (Brussels) with the grant AUHA09004 and FWO (Brussels, Belgium) projects no. G.0C12.13 and G.01769.09 and partly by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. ; |
Approved |
Most recent IF: 0.883; 2015 IF: 0.464 |
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Call Number |
UA @ admin @ c:irua:130244 |
Serial |
5876 |
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Author |
van Winsen, F.; de Mey, Y.; Lauwers, L.; Van Passel, S.; Vancauteren, M.; Wauters, E. |
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Title |
Determinants of risk behaviour : effects of perceived risks and risk attitude on farmer's adoption of risk management strategies |
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A1 Journal article |
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Year |
2016 |
Publication |
Journal Of Risk Research |
Abbreviated Journal |
J Risk Res |
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Volume |
19 |
Issue |
1 |
Pages |
56-78 |
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Keywords |
A1 Journal article; Sociology; Engineering Management (ENM) |
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Abstract |
The importance of risk perception and risk attitude for understanding individual's risk behaviour are independently well described in literature, but rarely combined in an integrated approach. In this study, we propose a model assuming the choice to implement certain risk management strategies to be directly driven by both perceptions of risks and risk attitude. Other determinants influence the intention to apply different risk strategies mainly indirectly, mediated by risk perception and risk attitude. This conceptual model is empirically tested, using structural equation modelling, for understanding the intention of farmers to implement different common risk management strategies at their farms. Data are gathered in a survey completed by 500 farmers from the Flanders region in Belgium, investigating attitudes towards farming, perceived past exposure to risk, socio-demographic characteristics, farm size, perceptions of the major sources of farm business risk, risk attitudes and the intention to apply common risk management strategies. Our major findings are: (i) perception of major farm business risks have no significant impact on the intention of applying any of the risk strategies under study, (ii) risk attitude does have a significant impact. Therefore, rather than objective risk faced and the subjective interpretation thereof, it is the general risk attitude that influence intended risk strategies to be implemented. A distinction can be made between farmers willing to take risk, who are more inclined to apply ex-ante risk management strategies and risk averse farmers who are less inclined to implement ex-ante risk management strategies but rather cope with the consequences and diminish their effects ex-post when risks have occurred. |
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Wos |
000365523100004 |
Publication Date |
2014-07-24 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1366-9877 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.34 |
Times cited |
25 |
Open Access |
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Notes |
; This work was supported by the agency for Innovation by Science and Technology [grant number 080508]. ; |
Approved |
Most recent IF: 1.34 |
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Call Number |
UA @ admin @ c:irua:130188 |
Serial |
6177 |
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Author |
Zhang, Y.-R.; Gao, F.; Li, X.-C.; Bogaerts, A.; Wang, Y.-N. |
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Title |
Fluid simulation of the bias effect in inductive/capacitive discharges |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of vacuum science and technology: A: vacuum surfaces and films |
Abbreviated Journal |
J Vac Sci Technol A |
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Volume |
33 |
Issue |
33 |
Pages |
061303 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Computer simulations are performed for an argon inductively coupled plasma (ICP) with a capacitive radio-frequency bias power, to investigate the bias effect on the discharge mode transition and on the plasma characteristics at various ICP currents, bias voltages, and bias frequencies. When the bias frequency is fixed at 13.56 MHz and the ICP current is low, e.g., 6A, the spatiotemporal averaged plasma density increases monotonically with bias voltage, and the bias effect is already prominent at a bias voltage of 90 V. The maximum of the ionization rate moves toward the bottom electrode, which indicates clearly the discharge mode transition in inductive/capacitive discharges. At higher ICP currents, i.e., 11 and 13 A, the plasma density decreases first and then increases with bias voltage, due to the competing mechanisms between the ion acceleration power dissipation and the capacitive power deposition. At 11 A, the bias effect is still important, but it is noticeable only at higher bias voltages. At 13 A, the ionization rate is characterized by a maximum at the reactor center near the dielectric window at all selected bias voltages, which indicates that the ICP power, instead of the bias power, plays a dominant role under this condition, and no mode transition is observed. Indeed, the ratio of the bias power to the total power is lower than 0.4 over a wide range of bias voltages, i.e., 0300V. Besides the effect of ICP current, also the effect of various bias frequencies is investigated. It is found that the modulation of the bias power to the spatiotemporal distributions of the ionization rate at 2MHz is strikingly different from the behavior observed at higher bias frequencies. Furthermore, the minimum of the plasma density appears at different bias voltages, i.e., 120V at 2MHz and 90V at 27.12 MHz. |
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Wos |
000365503800020 |
Publication Date |
2015-08-07 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0734-2101;1520-8559; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.374 |
Times cited |
9 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.374; 2015 IF: 2.322 |
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Call Number |
c:irua:126824 |
Serial |
1229 |
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Author |
van der Stam, W.; Bladt, E.; Rabouw, F.T.; Bals, S.; de Mello Donega, C. |
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Title |
Near-Infrared Emitting CuInSe/CuInS Dot Core/Rod Shell Heteronanorods by Sequential Cation Exchange |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
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Volume |
9 |
Issue |
9 |
Pages |
11430-11438 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The direct synthesis of heteronanocrystals (HNCs) combining different ternary semiconductors is challenging and has not yet been successful. Here, we report a sequential topotactic cation exchange (CE) pathway that yields CuInSe2/CuInS2 dot core/rod shell nanorods with near-infrared luminescence. In our approach, the Cu+ extraction rate is coupled to the In3+ incorporation rate by the use of a stoichiometric trioctylphosphine-InCl3 complex, which fulfills the roles of both In-source and Cu-extracting agent. In this way, Cu+ ions can be extracted by trioctylphosphine ligands only when the In-P bond is broken. This results in readily available In3+ ions at the same surface site from which the Cu+ is extracted, making the process a direct place exchange reaction and shifting the overall energy balance in favor of the CE. Consequently, controlled cation exchange can occur even in large and anisotropic heterostructured nanocrystals with preservation of the size, shape, and heterostructuring of the template NCs into the product NCs. The cation exchange is self-limited, stopping when the ternary core/shell CuInSe2/CuInS2 composition is reached. The method is very versatile, successfully yielding a variety of luminescent CuInX2 (X = S, Se, and Te) quantum dots, nanorods, and HNCs, by using Cd-chalcogenide NCs and HNCs as templates. The approach reported here thus opens up routes toward materials with unprecedented properties, which would otherwise remain inaccessible. |
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Address |
Debye Institute for Nanomaterials Science, Utrecht University , P.O. Box 80000, 3508 TA Utrecht, The Netherlands |
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Language |
English |
Wos |
000365464800094 |
Publication Date |
2015-10-09 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851;1936-086X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.942 |
Times cited |
88 |
Open Access |
OpenAccess |
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Notes |
The authors thank Gang Wang for XRD measurements and Eline Hutter for providing CdSe/CdS NRs. W.v.d.S. and C.d.M.D. acknowledge financial support from the division of Chemical Sciences (CW) of The Netherlands Organization for Scientific Research (NWO) under grant number ECHO.712.012.001. This work was supported by the European Research Council (ERC Starting Grant #335078 Colouratom). E.B. gratefully acknowledges financial support by the Flemish Fund for Scientific Research (FWO Vlaanderen).; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
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Call Number |
c:irua:129184 |
Serial |
3948 |
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Author |
Charkin, D.O.; Akinfiev, V.S.; Alekseeva, A.M.; Batuk, M.; Abakumov, A.M.; Kazakov, S.M. |
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Title |
Synthesis and cation distribution in the new bismuth oxyhalides with the Sillen-Aurivillius intergrowth structures |
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A1 Journal article |
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Year |
2015 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
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Volume |
44 |
Issue |
44 |
Pages |
20568-20576 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
About 20 new compounds with the Sillen-Aurivillius intergrowth structure, (MeMeBi3Nb2O11X)-Me-1-Bi-2 (Me-1 = Pb, Sr, Ba; Me-2 = Ca, Sr, Ba; X = Cl, Br, I), have been prepared. They are composed of stacking of [ANb(2)O(7)] perovskite blocks, fluorite-type [M2O2] blocks and halogen sheets. The cation distribution between the fluorite and perovskite layers has been studied for Ba2Bi3Nb2O11I, Ca1.25Sr0.75Bi3Nb2O11Cl, BaCaBi3Nb2O11Br and Sr2Bi3Nb2O11Cl. The smaller Me cations tend to reside in the perovskite block while the larger ones are situated in the fluorite-type block. The distribution of the elements was confirmed for BaCaBi3Nb2O11Br using energy dispersive X-ray analysis combined with scanning transmission electron microscopy (STEM-EDX). An electron diffraction study of this compound reveals a local symmetry lowering caused by weakly correlated rotation of NbO6 octahedra. Based on our findings, we suggest a new stability criterion for mixed-layer structures, which is that net charges of any two consecutive layers do not compensate for each other and only the whole layer sequence is electroneutral. |
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Place of Publication |
London |
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Wos |
000365411500036 |
Publication Date |
2015-10-30 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.029 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:130330 |
Serial |
4256 |
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Author |
Ercolani, G.; Gorle, C.; Garcia Sánchez, C.; Corbari, C.; Mancini, M. |
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Title |
RAMS and WRF sensitivity to grid spacing in large-eddy simulations of the dry convective boundary layer |
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A1 Journal article |
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Year |
2015 |
Publication |
Computers and fluids |
Abbreviated Journal |
Comput Fluids |
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Volume |
123 |
Issue |
123 |
Pages |
54-71 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Large-eddy simulations (LESS) are frequently used to model the planetary boundary layer, and the choice of the grid cell size, numerical schemes and sub grid model can significantly influence the simulation results. In the present paper the impact of grid spacing on LES of an idealized atmospheric convective boundary layer (CBL), for which the statistics and flow structures are well understood, is assessed for two mesoscale models: the Regional Atmospheric Modeling System (RAMS) and the Weather Research and Forecasting model (WRF). Nine simulations are performed on a fixed computational domain (6 x 6 x 2 km), combining three different horizontal (120, 60, 30 m) and vertical (20, 10, 5 m) spacings. The impact of the cell size on the CBL is investigated by comparing turbulence statistics and velocity spectra. The results demonstrate that both WRF and RAMS can perform LES of the CBL under consideration without requiring extremely high computational loads, but they also indicate the importance of adopting a computational grid that is adequate for the numerical schemes and subgrid models used. In both RAMS and WRF a horizontal cell size of 30 m is required to obtain a suitable turbulence reproduction throughout the CBL height. Considering the vertical grid spacing, WRF produced similar results for all the three tested values, while in RAMS it should be ensured that the aspect ratio of the cells does not exceed a value of 3. The two models were found to behave differently in function of the grid resolution, and they have different shortcomings in their prediction of CBL turbulence. WRF exhibits enhanced damping at the smallest scales, while RAMS is prone to the appearance of spurious fluctuations in the flow when the grid aspect ratio is too high. (C) 2015 Elsevier Ltd. All rights reserved. |
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Place of Publication |
Oxford |
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Wos |
000365367500006 |
Publication Date |
2015-10-08 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0045-7930 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.313 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.313; 2015 IF: 1.619 |
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Call Number |
UA @ lucian @ c:irua:130200 |
Serial |
4236 |
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Author |
Lybaert, J.; Maes, B.U.W.; Tehrani, K.A.; De Wael, K. |
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Title |
The electrochemistry of tetrapropylammonium perruthenate, its role in the oxidation of primary alcohols and its potential for electrochemical recycling |
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A1 Journal article |
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Year |
2015 |
Publication |
Electrochimica acta |
Abbreviated Journal |
Electrochim Acta |
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Volume |
182 |
Issue |
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Pages |
693-698 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Organic synthesis (ORSY) |
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Abstract |
The search for strategies aiming at more sustainable (oxidation) reactions has led to the application of electrochemistry for recycling the spent catalyst. In this work, an electrochemical study of the tetrapropylammonium perruthenate catalyst (TPAP) and its activity towards a primary alcohol, n-butanol, has been carried out as well as a control study with tert-butanol. The redox chemistry of TPAP and the transition between the perruthenate anion and ruthenium tetroxide in a non-aqueous solvent have been, for the first time, investigated in depth. The oxidation reaction of n-butanol in the presence of TPAP has been electrochemically elucidated by performing potentiostatic experiments and registration of the corresponding oxidation current. Furthermore, it was shown that, by applying a specific potential, the reoxidized TPAP is able to oxidize/convert the primary alcohol, paving the way for practical applications using TPAP in electrochemical synthesis. The conversion of n-butanol into n-butanal was proven by the use of GC-MS. |
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Wos |
000365075800084 |
Publication Date |
2015-09-25 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
0013-4686 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.798 |
Times cited |
2 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 4.798; 2015 IF: 4.504 |
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Call Number |
UA @ admin @ c:irua:127676 |
Serial |
5599 |
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Author |
Missault, N.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.; Van Duppen, B. |
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Title |
Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions |
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A1 Journal article |
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Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
92 |
Issue |
92 |
Pages |
195423 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study ballistic transport of Dirac fermions in silicene through arrays of barriers, of width d, in the presence of an exchange field M and a tunable potential of height U or depth-U. The spin-and valley-resolved conductances as functions of U or M, exhibit resonances away from the Dirac point (DP) and close to it a pronounced dip that becomes a gap when a critical electric field E-z is applied. This gap widens by increasing the number of barriers and can be used to realize electric field-controlled switching of the current. The spin p(s) and valley p(v) polarizations of the current near the DP increase with Ez or M and can reach 100% for certain of their values. These field ranges widen significantly by increasing the number of barriers. Also, ps and pv oscillate nearly periodically with the separation between barriers or wells and can be inverted by reversing M. |
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Place of Publication |
Lancaster, Pa |
Editor |
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Wos |
000364998100006 |
Publication Date |
2015-11-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121; 1550-235x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
54 |
Open Access |
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Notes |
; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.) and by the Flemish Science Foundation (FWO-Vl) with a Ph.D. research grant (B.V.D.). ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
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Call Number |
UA @ lucian @ c:irua:130264 |
Serial |
4247 |
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Author |
Kang, J.; Horzum, S.; Peeters, F.M. |
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Title |
Heterostructures of graphene and nitrogenated holey graphene: Moire pattern and Dirac ring |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
92 |
Issue |
92 |
Pages |
195419 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Nitrogenated holey graphene (NHG) is a recently synthesized two-dimensional material. In this paper the structural and electronic properties of heterostructures of graphene and NHG are investigated using first-principles and tight-binding calculations. Due to the lattice mismatch between NHG and graphene, the formation of a moire pattern is preferred in the graphene/NHG heterostructure, instead of a lattice-coherent structure. In moire-patterned graphene/NHG, the band gap opening at the K point is negligible, and the linear band dispersion of graphene survives. Applying an electric field modifies the coupling strength between the two atomic layers. The Fermi velocity upsilon(F) is reduced as compared to the one of pristine graphene, and its magnitude depends on the twist angle theta between graphene and NHG: For theta = 0 degrees, upsilon(F) is 30% of that of graphene, and it increases rapidly to a value of 80% with increasing theta. The heterostructure exhibits electron-hole asymmetry in upsilon(F), which is large for small theta. In NHG encapsulated between two graphene layers, a “Dirac ring” appears around the K point. Its presence is robust with respect to the relative stacking of the two graphene layers. These findings can be useful for future applications of graphene/NHG heterostructures. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000364998000006 |
Publication Date |
2015-11-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121; 1550-235x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
33 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
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Call Number |
UA @ lucian @ c:irua:130266 |
Serial |
4189 |
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| Permanent link to this record |
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Author |
Pouyet, E.; Cotte, M.; Fayard, B.; Salome, M.; Meirer, F.; Mehta, A.; Uffelman, E.S.; Hull, A.; Vanmeert, F.; Kieffer, J.; Burghammer, M.; Janssens, K.; Sette, F.; Mass, J. |
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Title |
2D X-ray and FTIR micro-analysis of the degradation of cadmium yellow pigment in paintings of Henri Matisse |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
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Volume |
121 |
Issue |
3 |
Pages |
967-980 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The chemical and physical alterations of cadmium yellow (CdS) paints in Henri Matisse's The Joy of Life (1905-1906, The Barnes Foundation) have been recognized since 2006, when a survey by portable X-ray fluorescence identified this pigment in all altered regions of the monumental painting. This alteration is visible as fading, discoloration, chalking, flaking, and spalling of several regions of light to medium yellow paint. Since that time, synchrotron radiation-based techniques including elemental and spectroscopic imaging, as well as X-ray scattering have been employed to locate and identify the alteration products observed in this and related works by Henri Matisse. This information is necessary to formulate one or multiple mechanisms for degradation of Matisse's paints from this period, and thus ensure proper environmental conditions for the storage and the display of his works. This paper focuses on 2D full-field X-ray Near Edge Structure imaging, 2D micro-X-ray Diffraction, X-ray Fluorescence, and Fourier Transform Infra-red imaging of the altered paint layers to address one of the long-standing questions about cadmium yellow alteration-the roles of cadmium carbonates and cadmium sulphates found in the altered paint layers. These compounds have often been assumed to be photo-oxidation products, but could also be residual starting reagents from an indirect wet process synthesis of CdS. The data presented here allow identifying and mapping the location of cadmium carbonates, cadmium chlorides, cadmium oxalates, cadmium sulphates, and cadmium sulphides in thin sections of altered cadmium yellow paints from The Joy of Life and Matisse's Flower Piece (1906, The Barnes Foundation). Distribution of various cadmium compounds confirms that cadmium carbonates and sulphates are photo-degradation products in The Joy of Life, whereas in Flower Piece, cadmium carbonates appear to have been a [(partially) unreacted] starting reagent for the yellow paint, a role previously suggested in other altered yellow paints. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000364914100017 |
Publication Date |
2015-06-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0947-8396; 1432-0630 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:130290 |
Serial |
7382 |
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Author |
Trentelman, K.; Janssens, K.; van der Snickt, G.; Szafran, Y.; Woollett, A.T.; Dik, J. |
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Title |
Rembrandt's An Old Man in Military Costume: the underlying image re-examined |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
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Volume |
121 |
Issue |
3 |
Pages |
801-811 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The painting An Old Man in Military Costume in the J. Paul Getty Museum, by Rembrandt Harmensz van Rijn, was studied using two complementary, element-specific imaging techniques-neutron activation autoradiography (NAAR) and macro-X-ray fluorescence (MA-XRF) mapping-to reveal the second, hidden painting. NAAR provided a strong image of the face and cloak of the underlying figure, along with an indication of the chemical composition. The single-element distribution maps produced by MA-XRF mapping provided additional details into the shape of the underlying image and the composition of the pigments used. The underlying figure's face is richer in mercury, indicative of the pigment vermilion, than the face of the figure on the surface. Likewise, the cloak of the underlying figure is richer in copper than the surface figure though the identity of the copper-containing pigment cannot be determined from these data. The use of iron earth pigments, specifically Si-rich umbers, is indicated through the complementary information provided by the NAAR and MA-XRF maps. These data are used to create a false color digital reconstruction, yielding the most detailed representation of the underlying painting to date. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000364914100003 |
Publication Date |
2015-08-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0947-8396 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.455 |
Times cited |
22 |
Open Access |
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Notes |
; The authors gratefully acknowledge the assistance of all those who aided in the examination of this painting over the decades, that has culminated in the work presented here. Particular thanks go to Mark Leonard (former head of Paintings Conservation at the J. Paul Getty Museum) and Henry Prask (NIST) for carrying out the NAAR analysis; John Twilley (former GCI Scientist) for early investigations; Andrea Sartorius (former JPGM Paintings intern) for creating a mock-up painting used in earlier phases of this work; Peter Reishig (former GCI intern) for compiling the NAAR data; Catherine Patterson, Lynn Lee, and David Carson (GCI Science) and Gene Karraker (JPGM Paintings Conservation) for helping with the setup and operation of the M6 Jetstream; and Giacomo Chiari (former head of GCI Science) for performing the XRD analysis. Koen Janssens and Geert van der Snickt acknowledge the Fund Inbev-Baillet Latour for financial support. Joris Dik acknowledges the help of the Netherlands Organization for Scientific Research (NWO) in the form of a VIDI grant in the Innovational Research Incentive Scheme. ; |
Approved |
Most recent IF: 1.455; 2015 IF: 1.704 |
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Call Number |
UA @ admin @ c:irua:130289 |
Serial |
5812 |
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| Permanent link to this record |
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Author |
Muguerra, H.; Pescheux, A.-C.; Meledin, A.; Van Tendeloo, G.; Soubeyroux, J.-L. |
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Title |
A La2−xGdxZr2O7layer deposited by chemical solution: a promising seed layer for the fabrication of high Jcand low cost coated conductors |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of materials chemistry C : materials for optical and electronic devices |
Abbreviated Journal |
J Mater Chem C |
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Volume |
3 |
Issue |
3 |
Pages |
11766-11772 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We deposited La2-xGdxZr2O7 seed layers by a chemical solution method on a Ni-5%W substrate to study the influence of these layers on the growth process of a 60 nm-thick La2Zr2O7 layer. We measured the performances of these new buffer layers integrated in a coated conductor with a 300 nm-thick Y0.5Gd0.5Ba2Cu3O7-x layer. For the seed layers{,} we considered two different gadolinium contents (x = 0.2 and x = 0.8) and three different thicknesses for these compositions (20 nm{,} 40 nm{,} and 60 nm). The most promising buffer layer stacks are those with 20 nm of the La1.8Gd0.2Zr2O7 layer or La1.2Gd0.8Zr2O7. Indeed the La2-xGdxZr2O7/La2Zr2O7 films are highly textured{,} similar to a 100 nm-thick La2Zr2O7 layer{,} but their roughness is four times lower. Moreover they contain less and smaller pores in the seed layer than a pure La2Zr2O7 layer. The surface of La2Zr2O7 is also homogenous and crystalline with an orientation deviation from the ideal ?011? (100) direction below 10[degree]. With the 20 nm La2-xGdxZr2O7 seed layers we obtain in the coated conductors an efficiently textured transfer with no gradual degradation from the substrate throughout the superconducting layer. The highest Tc and Jc values are achieved with the La1.8Gd0.2Zr2O7 layer and are{,} respectively{,} 91 K and 1.4 MA cm-2. This trend seems to be due to an improvement of the surface quality of the Ni5%W substrate by the addition of a thin seed layer. Our results offer the potential of the La2-xGdxZr2O7 seed layers as promising alternatives for the classic Ni-5%W/LZO/CeO2/YBCO architectures. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000364826000024 |
Publication Date |
2015-10-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2050-7526;2050-7534; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.256 |
Times cited |
4 |
Open Access |
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Notes |
This work was performed within the framework of the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280438), funded by the European Union. The authors also thank L. Porcar and P. Chometon for superconducting transition temperature and critical current density measurements and P. Odier for fruitful discussion. |
Approved |
Most recent IF: 5.256; 2015 IF: 4.696 |
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Call Number |
c:irua:130181 |
Serial |
3968 |
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Author |
Danthurebandara, M.; Van Passel, S.; Vanderreydt, I.; Van Acker, K. |
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Title |
Environmental and economic performance of plasma gasification in Enhanced Landfill Mining |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Waste Management |
Abbreviated Journal |
Waste Manage |
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Volume |
45 |
Issue |
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Pages |
458-467 |
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Keywords |
A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM) |
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Abstract |
This paper describes an environmental and economic assessment of plasma gasification, one of the viable candidates for the valorisation of refuse derived fuel from Enhanced Landfill Mining. The study is based on life cycle assessment and life cycle costing. Plasma gasification is benchmarked against conventional incineration, and the study indicates that the process could have significant impact on climate change, human toxicity, particulate matter formation, metal depletion and fossil depletion. Flue gas emission, oxygen usage and disposal of residues (plasmastone) are the major environmental burdens, while electricity production and metal recovery represent the major benefits. Reductions in burdens and improvements in benefits are found when the plasmastone is valorised in building materials instead of landfilling. The study indicates that the overall environmental performance of plasma gasification is better than incineration. The study confirms a trade-off between the environmental and economic performance of the discussed scenarios. Net electrical efficiency and investment cost of the plasma gasification process and the selling price of the products are the major economic drivers. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000364796800050 |
Publication Date |
2015-06-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0956-053x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.03 |
Times cited |
12 |
Open Access |
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Notes |
; The authors would like to acknowledge the funding of this study by the IWT-O&O ELFM project 'Closing the Circle & Enhanced Landfill Mining as part of the Transition to Sustainable Materials Management' and the valuable discussions with Group Machiels and VITO (Belgium). ; |
Approved |
Most recent IF: 4.03; 2015 IF: 3.220 |
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Call Number |
UA @ admin @ c:irua:129875 |
Serial |
6197 |
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Author |
Danthurebandara, M.; Van Passel, S.; Vanderreydt, I.; Van Acker, K. |
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Title |
Assessment of environmental and economic feasibility of Enhanced Landfill Mining |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Waste Management |
Abbreviated Journal |
Waste Manage |
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Volume |
45 |
Issue |
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Pages |
434-447 |
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Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
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Abstract |
This paper addresses the environmental and economic performance of Enhanced Landfill Mining (ELFM). Based on life cycle assessment and life cycle costing, a detailed model is developed and is applied to a case study, i.e. the first ELFM project in Belgium. The environmental and economic analysis is performed in order to study the valorisation of different waste types in the landfill, such as municipal solid waste, industrial waste and total waste. We found that ELFM is promising for the case study landfill as greater environmental benefits are foreseen in several impact categories compared to the landfills current situation (the Do-nothing scenario). Among the considered processes, the thermal treatment process dominates both the environmental and economic performances of ELFM. Improvements in the electrical efficiency of thermal treatment process, the calorific value of refuse derived fuel and recovery efficiencies of different waste fractions lead the performance of ELFM towards an environmentally sustainable and economically feasible direction. Although the environmental and economic profiles of ELFM will differ from case to case, the results of this analysis can be used as a benchmark for future ELFM projects. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000364796800048 |
Publication Date |
2015-02-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0956-053x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.03 |
Times cited |
30 |
Open Access |
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Notes |
; The authors would like to acknowledge the funding of this study by the IWT-O&O ELFM project 'Closing the Circle & Enhanced Landfill Mining as part of the Transition to Sustainable Materials Management' and the valuable discussions with Group Machiels (Belgium). ; |
Approved |
Most recent IF: 4.03; 2015 IF: 3.220 |
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Call Number |
UA @ admin @ c:irua:129878 |
Serial |
6156 |
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Author |
Michel, K.H.; Costamagna; Peeters, F.M. |
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Title |
Theory of thermal expansion in 2D crystals |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
252 |
Issue |
252 |
Pages |
2433-2437 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The thermal expansion alpha(T) in layered crystals is of fundamental and technological interest. As suggested by I. M. Lifshitz in 1952, in thin solid films (crystalline membranes) a negative contribution to alpha(T) is due to anharmonic couplings between in-plane stretching modes and out-of-plane bending (flexural modes). Genuine in-plane anharmonicities give a positive contribution to alpha(T). The competition between these two effects can lead to a change of sign (crossover) from a negative value of alpha(T) in a temperature (T) range T <= T-alpha to a positive value of alpha(T) for T > T-alpha in layered crystals. Here, we present an analytical lattice dynamical theory of these phenomena for a two-dimensional (2D) hexagonal crystal. We start from a Hamiltonian that comprises anharmonic terms of third and fourth order in the lattice displacements. The in-plane and out-of-plane contributions to the thermal expansion are studied as functions of T for crystals of different sizes. Besides, renormalization of the flexural mode frequencies plays a crucial role in determining the crossover temperature T-alpha. Numerical examples are given for graphene where the anharmonic couplings are determined from experiments. The theory is applicable to other layer crystals wherever the anharmonic couplings are known. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000364690400014 |
Publication Date |
2015-08-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
21 |
Open Access |
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Notes |
; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the Euro GRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 1.674; 2015 IF: 1.489 |
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Call Number |
UA @ lucian @ c:irua:130281 |
Serial |
4264 |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
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Title |
Phonon limited superconducting correlations in metallic nanograins |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
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Volume |
5 |
Issue |
5 |
Pages |
16515 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Conventional superconductivity is inevitably suppressed in ultra-small metallic grains for characteristic sizes smaller than the Anderson limit. Experiments have shown that above the Anderson limit the critical temperature may be either enhanced or reduced when decreasing the particle size, depending on the superconducting material. In addition, there is experimental evidence that whether an enhancement or a reduction is found depends on the strength of the electronphonon interaction in the bulk. We reveal how the strength of the e-ph interaction interplays with the quantum-size effect and theoretically obtain the critical temperature of the superconducting nanograins in excellent agreement with experimental data. We demonstrate that strong e-ph scattering smears the peak structure in the electronic density-of-states of a metallic grain and enhances the electron mass, and thereby limits the highest T-c achievable by quantum confinement. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000364647700001 |
Publication Date |
2015-11-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2045-2322 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.259 |
Times cited |
9 |
Open Access |
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Notes |
; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Research Foundation Flanders (FWO), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO. M.D.C. acknowledges fruitful discussions with V. Z. Kresin, S. N. Klimin and V. N. Gladilin. ; |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
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Call Number |
UA @ lucian @ c:irua:129543 |
Serial |
4224 |
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Author |
de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M. |
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Title |
Quantum tunneling between bent semiconductor nanowires |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
118 |
Issue |
118 |
Pages |
174301 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We theoretically investigate the electronic transport properties of two closely spaced L-shaped semiconductor quantum wires, for different configurations of the output channel widths as well as the distance between the wires. Within the effective-mass approximation, we solve the time-dependent Schrodinger equation using the split-operator technique that allows us to calculate the transmission probability, the total probability current, the conductance, and the wave function scattering between the energy subbands. We determine the maximum distance between the quantum wires below which a relevant non-zero transmission is still found. The transmission probability and the conductance show a strong dependence on the width of the output channel for small distances between the wires. (C) 2015 AIP Publishing LLC. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000364584200020 |
Publication Date |
2015-11-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
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Notes |
; A. A. Sousa was financially supported by CAPES, under the PDSE Contract No. BEX 7177/13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/2009 and by CAPES under process BEX 3299/13-9. This work was financially supported by PRONEX/CNPq/FUNCAP, the Science Without Borders program and the bilateral project CNPq-FWO. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
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Call Number |
UA @ lucian @ c:irua:129544 |
Serial |
4234 |
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Author |
Paolella, A.; Bertoni, G.; Hovington, P.; Feng, Z.; Flacau, R.; Prato, M.; Colombo, M.; Marras, S.; Manna, L.; Turner, S.; Van Tendeloo, G.; Guerfi, A.; Demopoulos, G.P.; Zaghib, K.; |
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Title |
Cation exchange mediated elimination of the Fe-antisites in the hydrothermal synthesis of LiFePO4 |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Nano energy |
Abbreviated Journal |
Nano Energy |
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Volume |
16 |
Issue |
16 |
Pages |
256-267 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In this work we elucidate the elimination of mechanism Fe-antisite defects in lithium iron phosphate (LiFePO4) during the hydrothermal synthesis. Compelling evidence of this effect is provided by combining Neutron Powder Diffraction (NPD), High Resolution (Scanning) Transmission Electron Microscopy (HR-(S)TEM), Electron Energy Loss Spectroscopy (EELS), X-Ray Photoelectron Spectroscopy (XPS) and calculations. We found: i) the first intermediate vivianite inevitably creates Fe-antisite defects in LiFePO4; ii) the removal of these antisite defects by cation exchange is assisted by a nanometer-thick amorphous layer, rich in Li, that enwraps the LiFePO4 crystals. |
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Place of Publication |
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Wos |
000364579300027 |
Publication Date |
2015-06-19 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2211-2855; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.343 |
Times cited |
27 |
Open Access |
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Notes |
The authorswanttoacknowledgeVincentGariepy,Cathe- rine Gagnon,JulieTrottier,DanielClement,Dr.CyrilFaure of IREQ,Dr.GaiaTomaselloofInstitutfürTheoretische PhysikFreieUniversitätBerlinandProf.MichelArmandof CICenergigune forhelpfuldiscussionsandtechnical supports. |
Approved |
Most recent IF: 12.343; 2015 IF: 10.325 |
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Call Number |
c:irua:127688 |
Serial |
296 |
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Author |
Bia, P.; Caratelli, D.; Mescia, L.; Gielis, J. |
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Title |
Analysis and synthesis of supershaped dielectric lens antennas |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
IET microwaves, antennas and propagation |
Abbreviated Journal |
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Volume |
9 |
Issue |
14 |
Pages |
1497-1504 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Mass communications; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
A novel class of supershaped dielectric lens antennas, whose geometry is described by the three-dimensional (3D) Gielis formula, is introduced and analysed. To this end, a hybrid modelling approach based on geometrical and physical optics is adopted in order to efficiently analyse the multiple wave reflections occurring within the lens and to evaluate the relevant impact on the radiation properties of the antenna under analysis. The developed modelling procedure has been validated by comparison with numerical results already reported in the literature and, afterwards, applied to the electromagnetic characterisation of Gielis dielectric lens antennas with shaped radiation pattern. Furthermore, a dedicated optimisation algorithm based on quantum particle swarm optimisation has been developed for the synthesis of 3D supershaped lens antennas with single feed, as well as with beamforming capabilities. |
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Wos |
000364491200002 |
Publication Date |
2015-08-14 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1751-8725 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:128659 |
Serial |
7441 |
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Author |
Vanrenterghem, B.; Geboes, B.; Bals, S.; Ustarroz, J.; Hubin, A.; Breugelmans, T. |
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Title |
Influence of the support material and the resulting particle distribution on the deposition of Ag nanoparticles for the electrocatalytic activity of benzyl bromide reduction |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
Appl Catal B-Environ |
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Volume |
181 |
Issue |
181 |
Pages |
542-549 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
tSilver nanoparticles (NPs) were deposited on nickel, titanium and gold substrates using a potentiostaticdouble-pulse method. The influence of the support material on both the morphology and the electro-catalytic activity of Ag NPs for the reduction reaction of benzyl bromide was investigated and comparedwith previous research regarding silver NPs on glassy carbon. Scanning electron microscopy (SEM) dataindicated that spherical monodispersed NPs were obtained on Ni, Au and GC substrate with an averageparticle size of respectively 216 nm, 413 nm and 116 nm. On a Ti substrate dendritic NPs were obtainedwith a larger average particle density of 480 nm. The influence of the support material on the electrocat-alytic activity was tested by means of cyclic voltammetry (CV) for the reduction reaction of benzylbromide(1 mM) in acetonitrile + 0.1 M tetrabutylammonium perchlorate (Bu4NClO4). When the nucleation poten-tial (En) was applied at high cathodic overpotential, a positive shift of the reduction potential was obtained.The nucleation (tn) and growth time (tg) mostly had an influence on the current density whereas longerdeposition times lead to larger current densities. For these three parameters an optimum was present.The best electrocatalytic activity was obtained with Ag NPs deposited on Ni were a shift of the reduc-tion peak potential of 145 mV for the reaction of benzyl bromide was measured in comparance to bulksilver. The deposition on Au substrate yielded a positive shift of 114 mV. There was no indication of analtered reaction mechanism as the reaction was characterized as diffusion controlled and the transfercoefficients were in accordance with bulk silver. There was a beneficial catalitic activity measured due tothe interplay between support and NPs. This resulted in a shift of the reduction peak potential of 34 mV(Ag NPs on Au) and 65 mV (Ag NPs on Ni) compared to Ag NPs on a GC substrate. |
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Place of Publication |
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Wos |
000364256000052 |
Publication Date |
2015-08-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0926-3373 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.446 |
Times cited |
16 |
Open Access |
OpenAccess |
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Notes |
The Quanta 250 FEG microscope of the Electron Microscopy forMaterial Science group at the University of Antwerp was fundedby the Hercules foundation of the Flemish Government. Sara Balsacknowledges financial support from European Research Council(ERC Starting Grant #335078-COLOURATOMS).; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); |
Approved |
Most recent IF: 9.446 |
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Call Number |
c:irua:128345 |
Serial |
4064 |
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Author |
Liu, J.; Hu, Z.-Y.; Peng, Y.; Huang, H.-W.; Li, Y.; Wu, M.; Ke, X.-X.; Van Tendeloo, G.; Su, B.-L. |
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Title |
2D ZnO mesoporous single-crystal nanosheets with exposed {0001} polar facets for the depollution of cationic dye molecules by highly selective adsorption and photocatalytic decomposition |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
Appl Catal B-Environ |
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Volume |
181 |
Issue |
181 |
Pages |
138-145 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Two dimensional (2D) ZnO nanosheets are ideal system for dimensionally confined transport phenomenon investigation owing to specific surface atomic configuration. Therefore, 2D ZnO porous nanosheets with single-crystal nature and {0001} polar facets, likely display some specific physicochemical properties. In this work, for the first time, 2D ZnO mesoporous single-crystal nanosheets (ZnO-MSN) with {0001} polar facets have been designed and prepared via an intriguing colloidal templating approach through controlling the infiltration speed for the suspension of EG-capped ZnO nanoparticles and polymer colloids. The EG-capped ZnO nanoparticles are very helpful for single-crystal nanosheet formation, while the polymer colloids play dual roles on the mesoporosity generation and {0001} polar facets formation within the mesopores. Such special 2D structure not only accelerates the hole-electron separation and the electron transportation owing to the single-crystal nature, but also enhances the selective adsorption of organic molecules owing to the porous structure and the exposed {0001} polar facets with more O-termination (000-1) surfaces: the 2D ZnO-MSN shows highly selective adsorption and significantly higher photodegradation for positively charged rhodamine B than those for negatively charged methyl orange and neutral phenol, comparing with ZnO nanoparticles (ZnO-NP) and ZnO commercial nanoparticles (ZnO-CNP) with high surface areas. This work may shed some light on better understanding the synthesis of 2D porous single-crystal nanosheet with exposed polar surfaces and photocatalytic mechanism of nanostructured semiconductors in a mixed organic molecules system. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000364256000015 |
Publication Date |
2015-08-01 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0926-3373; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.446 |
Times cited |
60 |
Open Access |
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Notes |
246791 Countatoms |
Approved |
Most recent IF: 9.446 |
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Call Number |
c:irua:127638 c:irua:127638 c:irua:127638 |
Serial |
10 |
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