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Records |
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Author |
Peirs, J.; Verleysen, P.; Tirry, W.; Rabet, L.; Schryvers, D.; Degrieck, J. |
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Title |
Dynamic shear localization in Ti6Al4V |
Type |
P1 Proceeding |
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Year |
2011 |
Publication |
Procedia Engineering
T2 – 11th International Conference on the Mechanical Behavior of Materials, (ICM), 2011, Como, ITALY (ICM11) |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-6 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
The alloy Ti6Al4V is known to be prone to the formation of adiabatic shear bands when dynamically loaded in shear. This causes a catastrophic decrease of the load carrying capacity and is usually followed by fracture. Although, the main mechanism is recognized to be the competition between strain hardening and thermal softening, a detailed understanding of the role of microstructural plasticity mechanisms and macroscopic loading conditions does not exist yet. To study strain localization and shear fracture, different high strain rate shear tests have been carried out: compression of hat-shaped specimens, torsion of thin walled tubular specimens and in-plane shear tests. The value of the three techniques in studying shear localization is evaluated. Post-mortem analysis of the fracture surface and the materials' microstructure is performed with optical and electron microscopy. In all cases a ductile fracture is observed. SEM and TEM techniques are used to study the local microstructure and composition in the shear band and as such the driving mechanism for the ASB formation. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of ICM11 |
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Place of Publication |
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Wos |
000300451302060 |
Publication Date |
2011-06-20 |
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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 |
10 |
Series Issue |
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Edition |
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ISSN |
1877-7058; |
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 |
4 |
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:113069 |
Serial |
767 |
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Permanent link to this record |
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Author |
Austing, D.G.; Payette, C.; Yu, G.; Gupta, J.A.; Aers, G.C.; Nair, S.V.; Partoens, B.; Amaha, S.; Tarucha, S. |
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Title |
Characterization and modeling of single-particle energy levels and resonant currents in a coherent quantum dot mixer |
Type |
P1 Proceeding |
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Year |
2011 |
Publication |
AIP conference proceedings
T2 – 30th International Conference on the Physics of Semiconductors (ICPS-30), JUL 25-30, 2010, Seoul, SOUTH KOREA |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-2 |
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Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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Abstract |
We characterize and model the single-particle energy level position and resonant current strength at a three-level crossing in a coherent mixer composed of two weakly coupled vertical quantum dots. In addition to clear anticrossing behavior, an otherwise strong resonance is completely extinguished at the center of the crossing. Despite the strong variation in energy level position and resonant current strength throughout the crossing region, the resonance widths and the sum of the branch currents are found to be approximately constant. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000301053000453 |
Publication Date |
2011-12-28 |
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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 |
1399 |
Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:113070 |
Serial |
314 |
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Permanent link to this record |
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Author |
Guttmann, P.; Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Umek, P.; Arcon, D.; Ewels, C.P.; Rehbein, S.; Heim, S.; Schneider, G. |
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Title |
TXM-NEXAFS of TiO2-based nanostructures |
Type |
P1 Proceeding |
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Year |
2011 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
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Volume |
1365 |
Issue |
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Pages |
437-440 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
In this work, electronic properties of individual TiOx-pristine nanoribbons (NR) prepared by hydrothermal treatment of anatase TiO(2) micro-particles were studied using the HZB transmission x-ray microscope (TXM) at the BESSY II undulator beamline U41-FSGM. NEXAFS is ideally suited to study TiO(2)-based materials because both the O K-edge and Ti L-edge features are very sensitive to the local bonding environment, providing diagnostic information about the crystal structures and oxidation states of various forms of titanium oxides and sub-oxides. TXM-NEXAFS combines full-field x-ray microscopy with spectroscopy, allowing the study of the electronic structure of individual nanostructures with spatial resolution better than 25 nm and a spectral resolution of up to E/Delta E = 10000. The typical image field in TXM-NEXAFS measurements is about 10 mu m. 10 mu m, which is large compared to the individual nanoparticle. Therefore, one image stack already contains statistically significant data. In addition, the directional electric field vector ((E) over bar) of the x-rays can be used as a “search tool” for the direction of chemical bonds of the atom selected by its absorption edge. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000298672400103 |
Publication Date |
2011-09-19 |
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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 |
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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 |
2 |
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:113071 |
Serial |
3789 |
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Permanent link to this record |
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Author |
Khalil-Allafi, J.; Amin-Ahmadi, B. |
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Title |
Influence of mold preheating and silicon content on microstructure and casting properties of ductile iron in permanent mold |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of iron and steel research international |
Abbreviated Journal |
J Iron Steel Res Int |
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Volume |
18 |
Issue |
3 |
Pages |
34-39 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The effects of the mold preheating and the silicon content of ductile iron on the percentage of carbides, graphite nodule counts and shrinkage volume were investigated. The results showed that the percentage of carbides and the shrinkage volume decreased when the mold preheating increased. The ductile iron with the carbon equivalent of 4.45% and the silicon content of 2.5% without any porosity defects was achieved when the mold preheating was 450 °C. Increasing the silicon content in the range of 2.1%3.3% led to the increase in graphite nodule count and graphite size and the decrease in percentage of carbides. It is due to the increase in induced expansion pressure during the graphite formation with the increasing of silicon content. The suitable condition for casting a sound product of ductile iron without the riser at the mold preheating temperature of 300 °C is the silicon content of 3.3% and carbon equivalent of 4.7%. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2011-03-28 |
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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 |
1006-706X; |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
0.836 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 0.836; 2011 IF: 0.213 |
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Call Number |
UA @ lucian @ c:irua:122043 |
Serial |
1629 |
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Permanent link to this record |
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Author |
Khalil-Allafi, J.; Amin-Ahmadi, B. |
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Title |
Effect of mold hardness on microstructure and contraction porosity in ductile cast iron |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of iron and steel research international |
Abbreviated Journal |
J Iron Steel Res Int |
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Volume |
18 |
Issue |
4 |
Pages |
44-47 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The effect of mold hardness on the microstructure of ductile iron and the contraction porosity was investigated. Molds with different hardnesses (0.41, 0.48, 0.55, 0.62 MPa) and a sand mold prepared by Co2 method were used. The influence of silicon content on the induced expansion pressure owing to the formation of graphite was also investigated. The contraction during solidification can be compensated by an induced expansion owing to the graphite relief when the hardness of mold increases; therefore, the possibility of achieving a sound product without using any riser increases. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2011-05-01 |
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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 |
1006-706X; |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
0.836 |
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: 0.836; 2011 IF: 0.213 |
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Call Number |
UA @ lucian @ c:irua:122044 |
Serial |
823 |
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Permanent link to this record |
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Author |
Béché, A.; Rouvière, J.L.; Barnes, J.P.; Cooper, D. |
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Title |
Dark field electron holography for strain measurement |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
111 |
Issue |
3 |
Pages |
227-238 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Dark field electron holography is a new TEM-based technique for measuring strain with nanometer scale resolution. Here we present the procedure to align a transmission electron microscope and obtain dark field holograms as well as the theoretical background necessary to reconstruct strain maps from holograms. A series of experimental parameters such as biprism voltage, sample thickness, exposure time, tilt angle and choice of diffracted beam are then investigated on a silicon-germanium layer epitaxially embedded in a silicon matrix in order to obtain optimal dark field holograms over a large field of view with good spatial resolution and strain sensitivity. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000288638200007 |
Publication Date |
2010-12-01 |
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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 |
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 |
31 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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Call Number |
UA @ lucian @ c:irua:136368 |
Serial |
4496 |
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Permanent link to this record |
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Author |
Cooper, D.; de la Peña, F.; Béché, A.; Rouvière, J.-L.; Servanton, G.; Pantel, R.; Morin, P. |
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Title |
Field mapping with nanometer-scale resolution for the next generation of electronic devices |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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Volume |
11 |
Issue |
11 |
Pages |
4585-4590 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In order to improve the performance of todays nanoscaled semiconductor devices, characterization techniques that can provide information about the position and activity of dopant atoms and the strain fields are essential. Here we demonstrate that by using a modern transmission electron microscope it is possible to apply multiple techniques to advanced materials systems in order to provide information about the structure, fields, and composition with nanometer-scale resolution. Off-axis electron holography has been used to map the active dopant potentials in state-of-the-art semiconductor devices with 1 nm resolution. These dopant maps have been compared to electron energy loss spectroscopy maps that show the positions of the dopant atoms. The strain fields in the devices have been measured by both dark field electron holography and nanobeam electron diffraction. |
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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 |
Washington |
Editor |
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Language |
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Wos |
000296674700014 |
Publication Date |
2011-10-05 |
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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 |
1530-6984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.712 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 12.712; 2011 IF: 13.198 |
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Call Number |
UA @ lucian @ c:irua:136369 |
Serial |
4499 |
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Permanent link to this record |
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Author |
Denneulin, T.; Rouvière, J.L.; Béché, A.; Py, M.; Barnes, J.P.; Rochat, N.; Hartmann, J.M.; Cooper, D. |
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Title |
The reduction of the substitutional C content in annealed Si/SiGeC superlattices studied by dark-field electron holography |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Semiconductor science and technology |
Abbreviated Journal |
Semicond Sci Tech |
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Volume |
26 |
Issue |
12 |
Pages |
1-10 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Si/Si(1 − x − y)GexCy superlattices are used in the construction of new microelectronic architectures such as multichannel transistors. The introduction of carbon in SiGe allows for compensation of the strain and to avoid plastic relaxation. However, the formation of incoherent β-SiC clusters during annealing limits the processability of SiGeC. This precipitation leads to a modification of the strain in the alloy due to the reduction of the substitutional carbon content. Here, we investigated the strain in annealed Si/Si0.744Ge0.244C0.012 superlattices grown by reduced pressure chemical vapour deposition using dark-field electron holography. The variation of the substitutional C content was calculated by correlating the results with finite-element simulations. The obtained values were then compared with Fourier-transformed infrared spectrometry measurements. It was shown that after annealing for 2 min at 1050 °C carbon no longer has any influence on strain in the superlattice, which behaves like pure SiGe. However, a significant proportion of substitutional C atoms remain in a third-nearest neighbour (3nn) configuration. It was deduced that the influence of 3nn C on strain is negligible and that only isolated atoms have a significant contribution. It was also proposed that the 3nn configuration is an intermediary step during the formation of SiC clusters. |
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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 |
London |
Editor |
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Language |
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Wos |
000300151300010 |
Publication Date |
2011-11-07 |
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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 |
0268-1242 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.305 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 2.305; 2011 IF: 1.723 |
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Call Number |
UA @ lucian @ c:irua:136427 |
Serial |
4508 |
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Permanent link to this record |
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Author |
Cooper, D.; Rouvière, J.-L.; Béché, A.; Kadkhodazadeh, S.; Semenova, E.S.; Dunin-Borkowsk, R. |
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Title |
Quantitative strain mapping of InAs/InP quantum dots with 1 nm spatial resolution using dark field electron holography |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
99 |
Issue |
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Pages |
261911-261913 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The optical properties of semiconductor quantum dots are greatly influenced by their strain state. Dark field electron holography has been used to measure the strain in InAsquantum dotsgrown in InP with a spatial resolution of 1 nm. A strain value of 5.4% ± 0.1% has been determined which is consistent with both measurements made by geometrical phase analysis of high angle annular dark field scanning transmission electron microscopy images and with simulations. |
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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 |
000298638500027 |
Publication Date |
2012-01-03 |
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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 |
0003-6951; 1077-3118 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
26 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
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Call Number |
UA @ lucian @ c:irua:136428 |
Serial |
4507 |
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Permanent link to this record |
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Author |
Delville, R.; Malard, B.; Pilch, J.; Sittner, P.; Schryvers, D. |
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Title |
Transmission electron microscopy investigation of dislocation slip during superelastic cycling of NiTi wires |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
International journal of plasticity |
Abbreviated Journal |
Int J Plasticity |
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Volume |
27 |
Issue |
2 |
Pages |
282-297 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Superelastic deformation of thin NiTi wires containing various nanograined microstructures was investigated by tensile cyclic loading with in situ evaluation of electric resistivity. Defects created by the superelastic cycling in these wires were analyzed by transmission electron microscopy. The role of dislocation slip in superelastic deformation is discussed. NiTi wires having finest microstructures (grain diameter <100 nm) are highly resistant against dislocation slip, while those with fully recrystallized microstructure and grain size exceeding 200 nm are prone to dislocation slip. The density of the observed dislocation defects increases significantly with increasing grain size. The upper plateau stress of the superelastic stressstrain curves is largely grain size independent from 10 up to 1000 nm. It is hence claimed that the HallPetch relationship fails for the stress-induced martensitic transformation in this grain size range. It is proposed that dislocation slip taking place during superelastic cycling is responsible for the accumulated irreversible strains, cyclic instability and degradation of functional properties. No residual martensite phase was found in the microstructures of superelastically cycled wires by TEM and results of the in situ electric resistance measurements during straining also indirectly suggest that none or very little martensite phase remains in the studied cycled superelastic wires after unloading. The accumulation of dislocation defects, however, does not prevent the superelasticity. It only affects the shape of the stressstrain response, makes it unstable upon cycling and changes the deformation mode from localized to homogeneous. The activity of dislocation slip during superelastic deformation of NiTi increases with increasing test temperature and ultimately destroys the superelasticity as the plateau stress approaches the yield stress for slip. Deformation twins in the austenite phase ({1 1 4} compound twins) were frequently found in cycled wires having largest grain size. It is proposed that they formed in the highly deformed B19′ martensite phase during forward loading and are retained in austenite after unloading. Such twinning would represent an additional deformation mechanism of NiTi yielding residual irrecoverable strains. |
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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 |
Oxford |
Editor |
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Language |
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Wos |
000284921800007 |
Publication Date |
2010-05-17 |
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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 |
0749-6419; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.702 |
Times cited |
157 |
Open Access |
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Notes |
Fwo; Iap |
Approved |
Most recent IF: 5.702; 2011 IF: 4.603 |
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Call Number |
UA @ lucian @ c:irua:84651 |
Serial |
3709 |
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Permanent link to this record |
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Author |
Neyts, E.; Maeyens, A.; Pourtois, G.; Bogaerts, A. |
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Title |
A density-functional theory simulation of the formation of Ni-doped fullerenes by ion implantation |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
49 |
Issue |
3 |
Pages |
1013-1017 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Using self-consistent KohnSham density-functional theory molecular dynamics simulations, we demonstrate the theoretical possibility to synthesize NiC60, the incarfullerene Ni@C60 and the heterofullerene C59Ni in an ion implantation setup. The corresponding formation mechanisms of all three complexes are elucidated as a function of the ion implantation energy and impact location, suggesting possible routes for selectively synthesizing these complexes. |
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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 |
Oxford |
Editor |
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Language |
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Wos |
000286683500032 |
Publication Date |
2010-11-14 |
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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 |
0008-6223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.337 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 6.337; 2011 IF: 5.378 |
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Call Number |
UA @ lucian @ c:irua:85139 |
Serial |
639 |
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Permanent link to this record |
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Author |
Tinck, S.; Bogaerts, A. |
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Title |
Computer simulations of an oxygen inductively coupled plasma used for plasma-assisted atomic layer deposition |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
20 |
Issue |
1 |
Pages |
015008-015008,10 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this paper, an O2 inductively coupled plasma used for plasma enhanced atomic layer deposition of Al2O3 thin films is investigated by means of modeling. This work intends to provide more information about basic plasma properties such as species densities and species fluxes to the substrate as a function of power and pressure, which might be hard to measure experimentally. For this purpose, a hybrid model developed by Kushner et al is applied to calculate the plasma characteristics in the reactor volume for different chamber pressures ranging from 1 to 10 mTorr and different coil powers ranging from 50 to 500 W. Density profiles of the various oxygen containing plasma species are reported as well as fluxes to the substrate under various operating conditions. Furthermore, different orientations of the substrate, which can be placed vertically or horizontally in the reactor, are taken into account. In addition, special attention is paid to the recombination process of atomic oxygen on the different reactor walls under the stated operating conditions. From this work it can be concluded that the plasma properties change significantly in different locations of the reactor. The plasma density near the cylindrical coil is high, while it is almost negligible in the neighborhood of the substrate. Ion and excited species fluxes to the substrate are found to be very low and negligible. Finally, the orientation of the substrate has a minor effect on the flux of O2, while it has a significant effect on the flux of O. In the horizontal configuration, the flux of atomic oxygen can be up to one order of magnitude lower than in the vertical configuration. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
|
Wos |
000286592200009 |
Publication Date |
2011-01-08 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.302 |
Times cited |
11 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
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Call Number |
UA @ lucian @ c:irua:85285 |
Serial |
467 |
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Permanent link to this record |
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Author |
van Holsbeke, C.; de Backer, J.; Vos, W.; Verdonck, P.; van Ransbeeck, P.; Claessens, T.; Braem, M.; Vanderveken, O.; de Backer, W. |
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Title |
Anatomical and functional changes in the upper airways of sleep apnea patients due to mandibular repositioning: a large scale study |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Journal of biomechanics |
Abbreviated Journal |
J Biomech |
|
|
Volume |
44 |
Issue |
3 |
Pages |
442-449 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) |
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Abstract |
The obstructive sleep apnea-hypopnea syndrome (OSAHS) is a sleep related breathing disorder. A popular treatment is the use of a mandibular repositioning appliance (MRA) which advances the mandibula during the sleep and decreases the collapsibility of the upper airway. The success rate of such a device is, however, limited and very variable within a population of patients. Previous studies using computational fluid dynamics have shown that there is a decrease in upper airway resistance in patients who improve clinically due to an MRA. In this article, correlations between patient-specific anatomical and functional parameters are studied to examine how MRA induced biomechanical changes will have an impact on the upper airway resistance. Low-dose computed tomography (CT) scans are made from 143 patients suffering from OSAHS. A baseline scan and a scan after mandibular repositioning (MR) are performed in order to study variations in parameters. It is found that MR using a simulation bite is able to induce resistance changes by changing the pharyngeal lumen. The change in minimal cross-sectional area is the best parameter to predict the change in upper airway resistance. Looking at baseline values, the ideal patients for MR induced resistance decrease seem to be women with short airways, high initial resistance and no baseline occlusion. |
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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 |
New York, N.Y. |
Editor |
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Language |
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Wos |
000287551000014 |
Publication Date |
2010-10-23 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
0021-9290; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.664 |
Times cited |
23 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 2.664; 2011 IF: 2.434 |
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Call Number |
UA @ lucian @ c:irua:85305 |
Serial |
112 |
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Permanent link to this record |
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Author |
Cao, S.; Nishida, M.; Schryvers, D. |
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Title |
Quantitative three-dimensional analysis of Ni4Ti3 precipitate morphology and distribution in polycrystalline Ni-Ti |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
|
|
Volume |
59 |
Issue |
4 |
Pages |
1780-1789 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The three-dimensional size, morphology and distribution of Ni4Ti3 precipitates in a Ni50.8Ti49.2 polycrystalline shape memory alloy with a heterogeneous microstructure have been investigated using a focused ion beam/scanning electron microscopy slice-and-view procedure. The mean volume, central plane diameter, thickness, aspect ratio and sphericity of the precipitates in the grain interior as well as near to the grain boundary were measured and/or calculated. The morphology of the precipitates was quantified by determining the equivalent ellipsoids with the same moments of inertia and classified according to the Zingg scheme. Also, the pair distribution functions describing the three-dimensional distributions were obtained from the coordinates of the precipitate mass centres. Based on this new data it is suggested that the existence of the heterogeneous microstructure could be due to a very small concentration gradient in the grains of the homogenized material and that the resulting multistage martensitic transformation originates in strain effects related to the size of the precipitates and scale differences of the available B2 matrix in between the precipitates. |
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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 |
Oxford |
Editor |
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Language |
|
Wos |
000287265100045 |
Publication Date |
2010-12-20 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1359-6454; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
5.301 |
Times cited |
34 |
Open Access |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 5.301; 2011 IF: 3.755 |
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|
Call Number |
UA @ lucian @ c:irua:85533 |
Serial |
2766 |
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Permanent link to this record |
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Author |
Mao, M.; Bogaerts, A. |
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Title |
Plasma chemistry modeling for an inductively coupled plasma used for the growth of carbon nanotubes |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
|
Volume |
275 |
Issue |
1 |
Pages |
012021,1-012021,9 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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|
Abstract |
A hybrid model, called the hybrid plasma equipment model (HPEM), is used to describe the plasma chemistry in an inductively coupled plasma, operating in a gas mixture of C2H2 with either H2 or NH3, as typically used for carbon nanotube (CNT) growth. Two-dimensional profiles of power density, electron temperature and density, gas temperature, and densities of some plasma species are plotted and analyzed. Besides, the fluxes of the various plasma species towards the substrate (where the CNTs can be grown), as well as the decomposition rates of the feedstock gases (C2H2, NH3 and H2), are calculated as a function of the C2H2 fraction in both gas mixtures. |
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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 |
Bristol |
Editor |
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Language |
|
Wos |
|
Publication Date |
2011-02-09 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
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|
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record |
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|
Impact Factor |
|
Times cited |
|
Open Access |
|
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|
Notes |
|
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:85859 |
Serial |
2631 |
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Permanent link to this record |
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Author |
Zelaya, E.; Schryvers, D. |
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Title |
Reducing the formation of FIB-induced FCC layers on Cu-Zn-Al austenite |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Microscopy research and technique |
Abbreviated Journal |
Microsc Res Techniq |
|
|
Volume |
74 |
Issue |
1 |
Pages |
84-91 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The irradiation effects of thinning a sample of a Cu-Zn-Al shape memory alloy to electron transparency by a Ga+ focused ion beam were investigated. This thinning method was compared with conventional electropolishing and Ar+ ion milling. No implanted Ga was detected but surface FCC precipitation was found as a result of the focused ion beam sample preparation. Decreasing the irradiation dose by lowering the energy and current of the Ga+ ions did not lead to a complete disappearance of the FCC structure. The latter could only be removed after gentle Ar+ ion milling of the sample. It was further concluded that the precipitation of the FCC is independent of the crystallographic orientation of the surface. |
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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 |
New York, N.Y. |
Editor |
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Language |
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Wos |
000285976000012 |
Publication Date |
2010-05-25 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1059-910X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.147 |
Times cited |
2 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 1.147; 2011 IF: 1.792 |
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Call Number |
UA @ lucian @ c:irua:85994 |
Serial |
2852 |
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Permanent link to this record |
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Author |
Tian, H.; Schryvers, D.; Liu, D.; Jiang, Q.; van Humbeeck, J. |
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Title |
Stability of Ni in nitinol oxide surfaces |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Acta biomaterialia |
Abbreviated Journal |
Acta Biomater |
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|
Volume |
7 |
Issue |
2 |
Pages |
892-899 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The stability of Ni in titanium oxide surface layers on nitinol wires known to release certain amounts of Ni was investigated by first principles density functional theory and transmission electron microscopy. The oxides were identified as a combination of TiO and TiO2 depending on the thickness of the layer. The calculations indicate that free Ni atoms can exist in TiO at ambient temperature while Ni particles form in TiO2, which was confirmed by the transmission electron microscopy observations. The results are discussed with respect to surface stability and Ni release due to free Ni atoms and Ni particles. |
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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 |
S.l. |
Editor |
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Language |
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Wos |
000286707700047 |
Publication Date |
2010-09-17 |
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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 |
|
Series Issue |
|
Edition |
|
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|
ISSN |
1742-7061; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
6.319 |
Times cited |
39 |
Open Access |
|
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|
Notes |
Fwo |
Approved |
Most recent IF: 6.319; 2011 IF: 4.865 |
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Call Number |
UA @ lucian @ c:irua:85998 |
Serial |
3128 |
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Permanent link to this record |
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Author |
Van Aert, S.; Batenburg, K.J.; Rossell, M.D.; Erni, R.; Van Tendeloo, G. |
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Title |
Three-dimensional atomic imaging of crystalline nanoparticles |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Nature |
Abbreviated Journal |
Nature |
|
|
Volume |
470 |
Issue |
7334 |
Pages |
374-377 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Determining the three-dimensional (3D) arrangement of atoms in crystalline nanoparticles is important for nanometre-scale device engineering and also for applications involving nanoparticles, such as optoelectronics or catalysis. A nanoparticles physical and chemical properties are controlled by its exact 3D morphology, structure and composition1. Electron tomography enables the recovery of the shape of a nanoparticle from a series of projection images2, 3, 4. Although atomic-resolution electron microscopy has been feasible for nearly four decades, neither electron tomography nor any other experimental technique has yet demonstrated atomic resolution in three dimensions. Here we report the 3D reconstruction of a complex crystalline nanoparticle at atomic resolution. To achieve this, we combined aberration-corrected scanning transmission electron microscopy5, 6, 7, statistical parameter estimation theory8, 9 and discrete tomography10, 11. Unlike conventional electron tomography, only two images of the targeta silver nanoparticle embedded in an aluminium matrixare sufficient for the reconstruction when combined with available knowledge about the particles crystallographic structure. Additional projections confirm the reliability of the result. The results we present help close the gap between the atomic resolution achievable in two-dimensional electron micrographs and the coarser resolution that has hitherto been obtained by conventional electron tomography. |
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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 |
London |
Editor |
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Language |
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Wos |
000287409100037 |
Publication Date |
2011-02-02 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
0028-0836;1476-4687; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
40.137 |
Times cited |
341 |
Open Access |
|
|
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 40.137; 2011 IF: 36.280 |
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Call Number |
UA @ lucian @ c:irua:86745 |
Serial |
3644 |
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Permanent link to this record |
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Author |
Peelaers, H.; Partoens, B.; Giantomassi, M.; Rangel, T.; Goossens, E.; Rignanese, G.-M.; Gonze, X.; Peeters, F.M. |
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Title |
Convergence of quasiparticle band structures of Si and Ge nanowires in the GW approximation and the validity of scissor shifts |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
83 |
Issue |
4 |
Pages |
045306-045306,6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Starting from fully converged density-functional theory calculations, the quasiparticle corrections are calculated for different sized Si and Ge nanowires using the GW approximation. The effectiveness of recently developed techniques in speeding up the convergence of the quasiparticle calculations is demonstrated. The complete quasiparticle band structures are also obtained using an interpolation technique based on maximallylocalized Wannier functions. From the quasiparticle results, we assess the correctness of the commonly applied scissor-shift correction. Dispersion changes are observed, which are also reflected in changes in the effective band masses calculated taking into account quasiparticle corrections. |
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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 |
|
Editor |
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Language |
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Wos |
000286771400004 |
Publication Date |
2011-01-21 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
3.836 |
Times cited |
18 |
Open Access |
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|
Notes |
; We are grateful to Yann Pouillon for valuable technical support with the build system of ABINIT, related to the WANNIER90 library. This work was supported by the Flemish Science Foundation (FWO-Vl) and by the Interuniversity Attraction Poles Program (P6/42)-Belgian State-Belgian Science Policy. X. G. and G.-M. R. acknowledge funding from the EU's 7th Framework Programme through the ETSF I3 e-Infrastructure project (Grant No. 211956), the Communaute francaise de Belgique through the Action de Recherche Concertee 07/12-003 “Nanosystemes hybrides metal-organiques,” and the Wallon Region Project No. 816849 “ European Theoretical Spectroscopy Facility” (WALL ETSF). M. G. acknowledges funding from the FRFC Project No. 2.4.589.09.F. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
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Call Number |
UA @ lucian @ c:irua:86905 |
Serial |
510 |
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Permanent link to this record |
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Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
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Title |
Stability and structures of the \epsilon-phases of iron nitrides and iron carbides from first principles |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
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Volume |
64 |
Issue |
3 |
Pages |
296-299 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
First-principles calculations were performed for the ε-phases and other iron carbides/nitrides with hexagonal close-packed Fe sublattices. Although these nitrides/carbides have similar crystal structures, they exhibit different chemical and physical properties. Relative to α-Fe, graphite and N2, all the ε-type nitrides are stable, while all the carbides are metastable. The lattice parameters of the ε-iron nitrides vary differently from those of the ε-carbides, as a function of the concentration of X (Xdouble bond; length as m-dashN, C). The structural relationships of ε-Fe2X with η-Fe2X and ζ-Fe2X are discussed. |
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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 |
Oxford |
Editor |
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Language |
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Wos |
000285323300022 |
Publication Date |
2010-09-02 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.747 |
Times cited |
29 |
Open Access |
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|
Notes |
|
Approved |
Most recent IF: 3.747; 2011 IF: 2.699 |
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Call Number |
UA @ lucian @ c:irua:86974 |
Serial |
3120 |
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Permanent link to this record |
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Author |
Simon, P.; Bogaerts, A. |
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Title |
Vibrational level population of nitrogen impurities in low-pressure argon glow discharges |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
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Volume |
26 |
Issue |
4 |
Pages |
804-810 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The vibrational level populations of the electronic ground state of the nitrogen molecule have been calculated for typical glow discharge conditions in argonnitrogen mixtures with nitrogen concentrations between 0.1 and 1%. Stationary solutions of the master equations of the vibrational levels have been obtained using numerical methods. The main mechanisms responsible for the population and depopulation of the vibrational levels, and for the overall shape of the vibrational distribution function are pointed out. It has been found that vibrationvibration collisions play only a minor role and therefore the population of the vibrational levels is basically determined by the electron temperature. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
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Language |
|
Wos |
000288703300012 |
Publication Date |
2010-12-07 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0267-9477;1364-5544; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.379 |
Times cited |
6 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.379; 2011 IF: 3.220 |
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Call Number |
UA @ lucian @ c:irua:87530 |
Serial |
3842 |
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Permanent link to this record |
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Author |
Yusupov, M.; Bultinck, E.; Depla, D.; Bogaerts, A. |
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Title |
Behavior of electrons in a dual-magnetron sputter deposition system : a Monte Carlo model |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
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Volume |
13 |
Issue |
|
Pages |
033018-033018,17 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A Monte Carlo model has been developed for investigating the electron behavior in a dual-magnetron sputter deposition system. To describe the three-dimensional (3D) geometry, different reference frames, i.e. a local and a global coordinate system, were used. In this study, the influence of both closed and mirror magnetic field configurations on the plasma properties is investigated. In the case of a closed magnetic field configuration, the calculated electron trajectories show that if an electron is emitted in (or near) the center of the cathode, where the influence of the magnetic field is low, it is able to travel from one magnetron to the other. On the other hand, when an electron is created at the race track area, it is more or less trapped in the strong magnetic field and cannot easily escape to the second magnetron region. In the case of a mirror magnetic field configuration, irrespective of where the electron is emitted from the cathode, it cannot travel from one magnetron to the other because the magnetic field lines guide the electron to the substrate. Moreover, the electron density and electron impact ionization rate have been calculated and studied in detail for both configurations. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
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Language |
|
Wos |
000289064600001 |
Publication Date |
2011-03-15 |
|
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.786 |
Times cited |
12 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.786; 2011 IF: 4.177 |
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|
Call Number |
UA @ lucian @ c:irua:87544 |
Serial |
224 |
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Permanent link to this record |
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Author |
Aerts, A.; Follens, L.R.A.; Biermans, E.; Bals, S.; Van Tendeloo, G.; Loppinet, B.; Kirschhock, C.E.A.; Martens, J.A. |
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Title |
Modelling of synchrotron SAXS patterns of silicalite-1 zeolite during crystallization |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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Volume |
13 |
Issue |
10 |
Pages |
4318-4325 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Synchrotron small angle X-ray scattering (SAXS) was used to characterize silicalite-1 zeolite crystallization from TEOS/TPAOH/water clear sol. SAXS patterns were recorded over a broad range of length scales, enabling the simultaneous monitoring of nanoparticles and crystals occurring at various stages of the synthesis. A simple two-population model accurately described the patterns. Nanoparticles were modeled by polydisperse coreshell spheres and crystals by monodisperse oblate ellipsoids. These models were consistent with TEM images. The SAXS results, in conjunction with in situ light scattering, showed that nucleation of crystals occurred in a short period of time. Crystals were uniform in size and shape and became increasingly anisotropic during growth. In the presence of nanoparticles, crystal growth was fast. During crystal growth, the number of nanoparticles decreased gradually but their size was constant. These observations suggested that the nanoparticles were growth units in an aggregative crystal growth mechanism. Crystals grown in the presence of nanoparticles developed a faceted habit and intergrowths. In the final stages of growth, nanoparticles were depleted. Concurrently, the crystal growth rate decreased significantly. |
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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 |
Cambridge |
Editor |
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Language |
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Wos |
000287584700017 |
Publication Date |
2011-01-24 |
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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 |
1463-9076;1463-9084; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.123 |
Times cited |
22 |
Open Access |
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Notes |
Fwo; Iap; Esteem 026019 |
Approved |
Most recent IF: 4.123; 2011 IF: 3.573 |
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Call Number |
UA @ lucian @ c:irua:87602 |
Serial |
2155 |
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Permanent link to this record |
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Author |
Heidari Mezerji, H.; van den Broek, W.; Bals, S. |
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Title |
A practical method to determine the effective resolution in incoherent experimental electron tomography |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
111 |
Issue |
5 |
Pages |
330-336 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
It is not straightforward to determine resolution for a 3D reconstruction when performing an electron tomography experiment. Different contributions such as missing wedge and misalignment add up and often influence the final resolution in an anisotropic manner. The conventional resolution measures can not be used for all of the reconstruction techniques, especially for iterative techniques which are more commonly used for electron tomography in materials science. Here we define a quantitative resolution measure that determines the resolution in three orthogonal directions of the reconstruction. As an application we use this measure to determine the optimum number of simultaneous iterative reconstruction technique (SIRT) iterations to reconstruct the gold nanoparticles, based on a high angle annular dark field STEM (HAADF-STEM) tilt series. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000289396900005 |
Publication Date |
2011-01-24 |
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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 |
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 |
26 |
Open Access |
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Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
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Call Number |
UA @ lucian @ c:irua:87606 |
Serial |
2688 |
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Permanent link to this record |
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Author |
Eckert, M.; Mortet, V.; Zhang, L.; Neyts, E.; Verbeeck, J.; Haenen, ken; Bogaerts, A. |
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Title |
Theoretical investigation of grain size tuning during prolonged bias-enhanced nucleation |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
23 |
Issue |
6 |
Pages |
1414-1423 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this paper, the effects of prolonged bias-enhanced nucleation (prolonged BEN) on the growth mechanisms of diamond are investigated by molecular dynamics (MD) and combined MD-Metropolis Monte Carlo (MD-MMC) simulations. First, cumulative impacts of CxHy+ and Hx+ on an a-C:H/nanodiamond composite were simulated; second, nonconsecutive impacts of the dominant ions were simulated in order to understand the observed phenomena in more detail. As stated in the existing literature, the growth of diamond structures during prolonged BEN is a process that takes place below the surface of the growing film. The investigation of the penetration behavior of CxHy+ and Hx+ species shows that the carbon-containing ions remain trapped within this amorphous phase where they dominate mechanisms like precipitation of sp3 carbon clusters. The H+ ions, however, penetrate into the crystalline phase at high bias voltages (>100 V), destroying the perfect diamond structure. The experimentally measured reduction of grain sizes at high bias voltage, reported in the literature, might thus be related to penetrating H+ ions. Furthermore, the CxHy+ ions are found to be the most efficient sputtering agents, preventing the build up of defective material. |
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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 |
Washington, D.C. |
Editor |
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Language |
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Wos |
000288291400011 |
Publication Date |
2011-02-23 |
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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 |
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 |
9 |
Open Access |
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Notes |
Iwt; Fwo; Esteem 026019; Iap |
Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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Call Number |
UA @ lucian @ c:irua:87642 |
Serial |
3605 |
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Permanent link to this record |
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Author |
Yusupov, M.; Bultinck, E.; Depla, D.; Bogaerts, A. |
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Title |
Elucidating the asymmetric behavior of the discharge in a dual magnetron sputter deposition system |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
98 |
Issue |
13 |
Pages |
131502-131502,3 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A magnetron discharge is characterized by drifts of the charged particles guiding center, caused by the magnetic field, in contrast to unmagnetized discharges. Because of these drifts, a pronounced asymmetry of the discharge can be observed in a dual magnetron setup. In this work, it is found that the shape of the discharge in a dual magnetron configuration depends on the magnetic field configuration. In a closed configuration, strong drifts were observed in one preferential direction, whereas in a mirror configuration the deflection of the discharge was not so pronounced. Our calculations confirm experimental observations. |
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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 |
000289153600017 |
Publication Date |
2011-04-01 |
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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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
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Call Number |
UA @ lucian @ c:irua:87867 |
Serial |
1026 |
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Permanent link to this record |
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Author |
De Bie, C.; Martens, T.; van Dijk, J.; Paulussen, S.; Verheyde, B.; Corthals, S.; Bogaerts, A. |
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Title |
Dielectric barrier discharges used for the conversion of greenhouse gases: modeling the plasma chemistry by fluid simulations |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
20 |
Issue |
2 |
Pages |
024008,1-024008,11 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The conversion of methane to value-added chemicals and fuels is considered to be one of the challenges of the 21st century. In this paper we study, by means of fluid modeling, the conversion of methane to higher hydrocarbons or oxygenates by partial oxidation with CO2 or O2 in a dielectric barrier discharge. Sixty-nine different plasma species (electrons, ions, molecules, radicals) are included in the model, as well as a comprehensive set of chemical reactions. The calculation results presented in this paper include the conversion of the reactants and the yields of the reaction products as a function of residence time in the reactor, for different gas mixing ratios. Syngas (i.e. H2 + CO) and higher hydrocarbons (C2Hx) are typically found to be important reaction products. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000290719900009 |
Publication Date |
2011-04-02 |
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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 |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
38 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
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Call Number |
UA @ lucian @ c:irua:87868 |
Serial |
689 |
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Permanent link to this record |
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Author |
Si, X.-J.; Zhao, S.-X.; Xu, X.; Bogaerts, A.; Wang, Y.-N. |
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Title |
Fluid simulations of frequency effects on nonlinear harmonics in inductively coupled plasma |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Physics of plasmas |
Abbreviated Journal |
Phys Plasmas |
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Volume |
18 |
Issue |
3 |
Pages |
033504-033504,9 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A fluid model is self-consistently established to investigate the harmonic effects in an inductively coupled plasma, where the electromagnetic field is solved by the finite difference time domain technique. The spatiotemporal distribution of harmonic current density, harmonic potential, and other plasma quantities, such as radio frequency power deposition, plasma density, and electron temperature, have been investigated. Distinct differences in current density have been observed when calculated with and without Lorentz force, which indicates that the nonlinear Lorentz force plays an important role in the harmonic effects, especially at low frequencies. Moreover, the even harmonics are larger than the odd harmonics both in the current density and the potential. Finally, the dependence of various plasma quantities with and without the Lorentz force on various driving frequencies is also examined. It is shown that the deposited power density decreases and the depth of penetration increases slightly because of the Lorentz force. The electron density increases distinctly while the electron temperature remains almost the same when the Lorentz force is taken into account. |
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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 |
Woodbury, N.Y. |
Editor |
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Language |
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Wos |
000289151900073 |
Publication Date |
2011-03-18 |
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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 |
1070-664X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.115 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.115; 2011 IF: 2.147 |
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Call Number |
UA @ lucian @ c:irua:87876 |
Serial |
1233 |
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Permanent link to this record |
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Author |
d' Hondt, H. |
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Title |
Characterization of anion deficient perovskites |
Type |
Doctoral thesis |
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Year |
2011 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
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Abstract |
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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 |
Antwerpen |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
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ISBN |
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Additional Links |
UA library record |
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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 |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:87905 |
Serial |
317 |
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Permanent link to this record |
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Author |
Li, Y.; Tan, H.; Yang, X.-Y.; Goris, B.; Verbeeck, J.; Bals, S.; Colson, P.; Cloots, R.; Van Tendeloo, G.; Su, B.-L. |
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Title |
Well shaped Mn3O4 nano-octahedra with anomalous magnetic behavior and enhanced photodecomposition properties |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Small |
Abbreviated Journal |
Small |
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Volume |
7 |
Issue |
4 |
Pages |
475-483 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Very uniform and well shaped Mn3O4 nano-octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape-directing agent. The nano-octahedra formation mechanism is monitored. The shape and crystal orientation of the nanoparticles is reconstructed by scanning electron microscopy and electron tomography, which reveals that the nano-octahedra only selectively expose {101} facets at the external surfaces. The magnetic testing demonstrates that the Mn3O4 nano-octahedra exhibit anomalous magnetic properties: the Mn3O4 nano-octahedra around 150 nm show a similar Curie temperature and blocking temperature to Mn3O4 nanoparticles with 10 nm size because of the vertical axis of [001] plane and the exposed {101} facets. With these Mn3O4 nano-octahedra as a catalyst, the photodecomposition of rhodamine B is evaluated and it is found that the photodecomposition activity of Mn3O4 nano-octahedra is much superior to that of commercial Mn3O4 powders. The anomalous magnetic properties and high superior photodecomposition activity of well shaped Mn3O4 nano-octahedra should be related to the special shape of the nanoparticles and the abundantly exposed {101} facets at the external surfaces. Therefore, the shape preference can largely broaden the application of the Mn3O4 nano-octahedra. |
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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 |
Weinheim |
Editor |
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Language |
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Wos |
000288080400008 |
Publication Date |
2011-01-21 |
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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 |
1613-6810; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.643 |
Times cited |
131 |
Open Access |
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Notes |
This work was realized in the frame of an Interuniversity Attraction Poles Program (Inanomat-P6/17)-Belgian State-Belgian Science Policy and the project “Redugaz”, financially supported by the European community and the Wallon government in the frame of Interreg IV (France-Wallonie). B. L. S. acknowledges the Chinese Central Government for an “Expert of the State” position in the program of “Thousand talents” and the Chinese Ministry of Education for a Changjiang Scholar position at the Wuhan University of Technology. H. T. acknowledges the financial support from FWO-Vlaanderen (Project nr. G.0147.06). J.V. thanks the financial support from the European Union under Framework 6 program for Integrated Infrastructure Initiative, Reference 026019 ESTEEM. |
Approved |
Most recent IF: 8.643; 2011 IF: 8.349 |
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Call Number |
UA @ lucian @ c:irua:87908 |
Serial |
3914 |
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Permanent link to this record |