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Author |
Sánchez-Muñoz, L.; García-Guinea, J.; Zagorsky, V.Y.; Juwono, T.; Modreski, P.J.; Cremades, A.; Van Tendeloo, G.; de Moura, O.J.M. |
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Title |
The evolution of twin patterns in perthitic K-feldspar from garnitic pegmatites |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Canadian mineralogist |
Abbreviated Journal |
Can Mineral |
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Volume |
50 |
Issue |
4 |
Pages |
989-1024 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Grains of K-feldspar are commonly seen as heterogeneous mixtures of mineral species and varieties with random microstructures. Most consider that observable features arise from incomplete re-equilibrations owing to slow kinetic and localized effects of aqueous fluids (catalyst), with geological environment and chemical impurities playing only a secondary role. Here, an alternative approach is explored by studying well-preserved regularities in the twin patterns of K-feldspars formed in the subsolidus stage from a historical perspective. Selected samples from granitic pegmatites were studied by polarized light optical microscopy (PLOM), electron-probe micro-analysis (EPMA), scanning (SEM) and transmission electron microscopy (TEM), cathodoluminescence imaging (CL), micro-Raman spectroscopy (MRS) and 31P nuclear magnetic resonance (NMR). We have found that the essential feature of this crystalline medium is the astounding capability to recrystallize in self-organized twin patterns. The mechanism involves coupling between short-range atomic motion, and long-range displacive correlations propagated as ideal and non-ideal Albite and Pericline orientations. We suggest a general evolutionary process to explain the development of macroscopic twin patterns in microcline, based on three twin generations as microtwins, macrotwins and cryptotwins. Evolutionary variants also were identified; they depend on both internal crystallochemical features and an external geological stimulus. We suggest a continuous monoclinictriclinic transformation for impure K-feldspar, whereas a discontinuous inversion occurs where the starting composition is close to the ideal chemical formula. Twin patterns can evolve by twin coarsening to single-orientation microcline if the system releases energy, or by twin fragmentation to finely twinned microcline if the system stores energy. Hence, K-feldspar is seen here as a very sensitive medium in which precious geological information is recorded in the form of twin patterns, and thus useful for general geological challenges. |
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Publisher |
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Place of Publication |
Toronto |
Editor |
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Language |
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Wos |
000314174400015 |
Publication Date |
2012-10-29 |
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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 |
0008-4476;1499-1276; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
0.817 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 0.817; 2012 IF: 1.180 |
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Call Number |
UA @ lucian @ c:irua:101781 |
Serial |
1103 |
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Permanent link to this record |
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Author |
Salman, O.U.; Finel, A.; Delville, R.; Schryvers, D. |
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Title |
The role of phase compatibility in martensite |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of applied physics
T2 – 22nd International Symposium on Integrated Functionalities (ISIF), JUN 13-16, 2010, San Juan, PR |
Abbreviated Journal |
J Appl Phys |
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Volume |
111 |
Issue |
10 |
Pages |
103517 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Shape memory alloys inherit their macroscopic properties from their mesoscale microstructure originated from the martensitic phase transformation. In a cubic to orthorhombic transition, a single variant of martensite can have a compatible (exact) interface with the austenite for some special lattice parameters in contrast to conventional austenite/twinned martensite interface with a transition layer. Experimentally, the phase compatibility results in a dramatic drop in thermal hysteresis and gives rise to very stable functional properties over cycling. Here, we investigate the microstructures observed in Ti50Ni50-xPdx alloys that undergo a cubic to orthorhombic martensitic transformation using a three-dimensional phase field approach. We will show that the simulation results are in very good agreement with transmission electron microscopy observations. However, the understanding of the drop in thermal hysteresis requires the coupling of phase transformation with plastic activity. We will discuss this point within the framework of thermoelasticity, which is a generic feature of the martensitic transformation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4712629] |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
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Wos |
000305363700053 |
Publication Date |
2012-05-21 |
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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 |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 2012 IF: 2.210 |
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Call Number |
UA @ lucian @ c:irua:100310 |
Serial |
2919 |
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Permanent link to this record |
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Author |
Fei, G.; Xue-Chun, L.; Zhao, S.-X.; You-Nian, W. |
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Title |
Spatial variation behaviors of argon inductively coupled plasma during discharge mode transition |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Chinese physics B |
Abbreviated Journal |
Chinese Phys B |
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Volume |
21 |
Issue |
7 |
Pages |
075203 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A Langmuir probe and an ICCD are employed to study the discharge mode transition in Ar inductively coupled plasma. Electron density and plasma emission intensity are measured during the E (capacitive discharge) to H (inductive discharge) mode transitions at different pressures. It is found that plasma exists with a low electron density and a weak emission intensity in the E mode, while it has a high electron density and a strong emission intensity in the H mode. Meanwhile, the plasma emission intensity spatial (2D image) profile is symmetrical in the H mode, but the 2D image is an asymmetric profile in the E mode. Moreover, the electron density and emission intensity jump up discontinuously at high pressure, but increase almost continuously at the E to H mode transition under low pressure. |
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Corporate Author |
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Thesis |
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Publisher |
IOP publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000306558300058 |
Publication Date |
2012-07-19 |
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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 |
1674-1056; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.223 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.223; 2012 IF: 1.148 |
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Call Number |
UA @ lucian @ c:irua:100843 |
Serial |
3065 |
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Permanent link to this record |
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Author |
Gontard, L.C.; Jinschek, J.R.; Ou, H.; Verbeeck, J.; Dunin-Borkowski, R.E. |
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Title |
Three-dimensional fabrication and characterisation of core-shell nano-columns using electron beam patterning of Ge-doped SiO2 |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
26 |
Pages |
263113 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A focused electron beam in a scanning transmission electron microscope (STEM) is used to create arrays of core-shell structures in a specimen of amorphous SiO2 doped with Ge. The same electron microscope is then used to measure the changes that occurred in the specimen in three dimensions using electron tomography. The results show that transformations in insulators that have been subjected to intense irradiation using charged particles can be studied directly in three dimensions. The fabricated structures include core-shell nano-columns, sputtered regions, voids, and clusters. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4731765] |
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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 |
000305831500081 |
Publication Date |
2012-06-28 |
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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 |
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 |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:100337 |
Serial |
3651 |
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Permanent link to this record |
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Author |
Badalyan, S.M.; Peeters, F.M. |
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Title |
Electron-phonon bound state in graphene |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
20 |
Pages |
205453-205453,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The fine structure of the Dirac energy spectrum in graphene induced by electron-optical phonon coupling is investigated in the portion of the spectrum near the phonon emission threshold. The derived new dispersion equation in the immediate neighborhood below the threshold corresponds to an electron-phonon bound state. We find that the singular vertex corrections beyond perturbation theory strongly increase the electron-phonon binding energy scale. The predicted enhancement of the effective electron-phonon coupling can be measured using angle-resolved spectroscopy. |
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Place of Publication |
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Wos |
000304649400002 |
Publication Date |
2012-05-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
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Notes |
; We thank E. Rashba for the useful discussion and acknowledge support from the Belgian Science Policy (IAP) and BELSPO. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98939 |
Serial |
982 |
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Permanent link to this record |
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Author |
Brück, S.; Paul, M.; Tian, H.; Müller, A.; Kufer, D.; Praetorius, C.; Fauth, K.; Audehm, P.; Goering, E.; Verbeeck, J.; Van Tendeloo, G.; Sing, M.; Claessen, R.; |
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Title |
Magnetic and electronic properties of the interface between half metallic Fe3O4 and semiconducting ZnO |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
8 |
Pages |
081603-081603,4 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We have investigated the magnetic depth profile of an epitaxial Fe3O4 thin film grown directly on a semiconducting ZnO substrate by soft x-ray resonant magnetic reflectometry (XRMR) and electron energy loss spectroscopy (EELS). Consistent chemical profiles at the interface between ZnO and Fe3O4 are found from both methods. Valence selective EELS and XRMR reveal independently that the first monolayer of Fe at the interface between ZnO and Fe3O4 contains only Fe3+ ions. Besides this narrow 2.5 Å interface layer, Fe3O4 shows magnetic bulk properties throughout the whole film making highly efficient spin injection in this system feasible. |
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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 |
000300711200014 |
Publication Date |
2012-02-22 |
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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 |
12 |
Open Access |
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Notes |
The authors thank E. Pellegrin for helpful comments and S. Macke for help with the software REMAGX. S.B. acknowledges financial support by the HZB, Berlin, and the Australian Government via Grant No. RM08550. H.T. acknowledges funding from GOA project “XANES meets ELNES,” J.V. and G.V.T. acknowledge funding from the European Research Council under Grant No. 46791-COUN-TATOMS. The authors acknowledge financial support by the DFG through Forschergruppe FOR 1162. |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:95041UA @ admin @ c:irua:95041 |
Serial |
1860 |
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Permanent link to this record |
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Author |
Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Hadermann, J.; Hodges, J.P.; Herber, R.H.; Nowik, I.; Greenblatt, M.; |
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Title |
Magnetic and structural studies of the multifunctional material SrFe0.75Mo0.25O3-\text{\textgreek{d}} |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
22 |
Pages |
12273-12280 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
SrFe0.75Mo0.25O3-delta has been recently discovered as an extremely efficient electrode for intermediate temperature solid oxide fuel cells (IT-SOFCs). We have performed structural and magnetic studies to fully characterize this multifunctional material. We have observed by powder neutron diffraction (PND) and transmission electron microscopy (TEM) that its crystal symmetry is better explained with a tetragonal symmetry (I4/mcm space group) than with the previously reported orthorhombic symmetry (Pnma space group). The temperature dependent magnetic properties indicate an exceptionally high magnetic ordering temperature (T-N similar to 750 K), well above room temperature. The ordered magnetic structure at low temperature was determined by PND to be an antiferromagnetic coupling of the Fe cations. Mossbauer spectroscopy corroborated the PND results. A detailed study, with X-ray absorption spectroscopy (XAS), in agreement with the Mossbauer results, confirmed the formal oxidation states of the cations to be mixed valence Fe3+/4+ and Mo6+. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000311173700024 |
Publication Date |
2012-10-26 |
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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 |
0020-1669;1520-510X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:105142 |
Serial |
1862 |
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Permanent link to this record |
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Author |
Renard, K.; Idrissi, H.; Schryvers, D.; Jacques, P.J. |
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Title |
Multiscale characterization of the work hardening mechanisms in Fe-Mn based TWIP steels |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Steel research international |
Abbreviated Journal |
Steel Res Int |
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Volume |
83 |
Issue |
4 |
Pages |
385-390 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
When strained in tension, high-manganese austenitic twinning induced plasticity (TWIP) steels achieve very high strength and elongation before necking. The main hypotheses available in the literature about the origin of their excellent work hardening include deformation twinning and dynamic strain ageing. In order to provide some answers, various experiments at different scales were conducted on FeMnC steels and the Fe28 wt%Mn3.5 wt%Al2.8 wt%Si alloy. At a macroscopic scale, tensile tests were performed on all the studied grades. It was shown that, though the FeMnAlSi based alloy retains very high elongation, the FeMnC steels properties are even more extraordinary. Tensile tests at different strain rates with the help of digital image correlation were also performed on the Fe20 wt%Mn1.2 wt%C steel to study the PLC effect occurring in this type of steel. It is suggested that supplementary hardening could come from reorientation of MnC pairs in the cores of the dislocations. At a microscopic scale, the Fe20 wt%Mn1.2 wt%C TWIP steel and the FeMnAlSi grade were thoroughly investigated by means of in situ TEM analysis. In the FeMnC steel, the formed twins could also lead to a composite effect, since they contain plenty of sessile dislocations. In the FeMnAlSi alloy, mechanical twins are thicker and contain fewer defects, leading to a lower work hardening than the other grade. |
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Corporate Author |
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Thesis |
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Publisher |
Verlag Stahleisen |
Place of Publication |
Düsseldorf |
Editor |
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Language |
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Wos |
000302471600016 |
Publication Date |
2012-02-22 |
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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 |
1611-3683; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.235 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.235; 2012 IF: 0.493 |
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Call Number |
UA @ lucian @ c:irua:97391 |
Serial |
2239 |
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Permanent link to this record |
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Author |
Tytgat, T.; Hauchecorne, B.; Abakumov, A.M.; Smits, M.; Verbruggen, S.W.; Lenaerts, S. |
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Title |
Photocatalytic process optimisation for ethylene oxidation |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
209 |
Issue |
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Pages |
494-500 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
When studying photocatalysis it is important to consider, beside the chemical approach, the engineering part related to process optimisation. To achieve this a fixed bed photocatalytic set-up consisting of different catalyst placings, in order to vary catalyst distribution, is studied. The use of a fixed quantity of catalyst placed packed or randomly distributed in the reactor, results in an almost double degradation for the distributed catalyst. Applying this knowledge leads to an improved performance with limited use of catalyst. A reactor only half filled with catalyst leads to higher degradation performance compared to a completely filled reactor. Taking into account this simple process optimisation by better distributing the catalyst a more sustainable photocatalytic air purification process is achieved. (C) 2012 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lausanne |
Editor |
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Language |
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Wos |
000311190500058 |
Publication Date |
2012-08-22 |
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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 |
1385-8947; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
12 |
Open Access |
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Notes |
; We are grateful for the delivered photocatalyst by Evonik as well as for the PhD grant (T. Tytgat) given by the Institute of Innovation by Science and Technology in Flanders (IWT). ; |
Approved |
Most recent IF: 6.216; 2012 IF: 3.473 |
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Call Number |
UA @ lucian @ c:irua:105185 |
Serial |
2609 |
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Permanent link to this record |
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Author |
Turner, S.; Egoavil, R.; Batuk, M.; Abakumov, A.A.; Hadermann, J.; Verbeeck, J.; Van Tendeloo, G. |
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Title |
Site-specific mapping of transition metal oxygen coordination in complex oxides |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
101 |
Issue |
24 |
Pages |
241910 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We demonstrate site-specific mapping of the oxygen coordination number for transition metals in complex oxides using atomically resolved electron energy-loss spectroscopy in an aberration-corrected scanning transmission electron microscope. Pb2Sr2Bi2Fe6O16 contains iron with a constant Fe3+ valency in both octahedral and tetragonal pyramidal coordination and is selected to demonstrate the principle of site-specific coordination mapping. Analysis of the site-specific Fe-L2,3 data reveals distinct variations in the fine structure that are attributed to Fe in a six-fold (octahedron) or five-fold (distorted tetragonal pyramid) oxygen coordination. Using these variations, atomic resolution coordination maps are generated that are in excellent agreement 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 |
000312490000035 |
Publication Date |
2012-12-12 |
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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 |
12 |
Open Access |
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Notes |
Fwo; Countatoms; Vortex; Esteem 312483; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:105302UA @ admin @ c:irua:105302 |
Serial |
3030 |
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Permanent link to this record |
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Author |
Ramezanipour, F.; Greedan, J.E.; Siewenie, J.; Donaberger, R.L.; Turner, S.; Botton, G.A. |
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Title |
A vacancy-disordered, oxygen-deficient perovskite with long-range magnetic ordering : local and average structures and magnetic properties of Sr2Fe1.5Cr0.5O5 |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
4 |
Pages |
2638-2644 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The local and average crystal structures and magnetic properties of the oxygen-deficient perovskite Sr2Fe1.5Cr0.5O5+y were studied using powder X-ray and neutron diffraction, neutron-pair distribution function analysis, and electron energy-loss spectroscopy. This material crystallizes in the cubic Pm3̅m space group, with a = 3.94491(14) Å. The oxygen vacancies are distributed randomly throughout the perovskite-type structure, and the average coordination number of the Fe(Cr) sites is 5. Refinement of the neutron diffraction data indicates y 0.05. This is in discordance with an earlier report on a material with the same nominal composition and cell constant. Electron energy-loss Cr L2,3-edge spectroscopy shows that Cr3+ is present, which is also contrary to previous speculation. Neutron-pair distribution function studies show that a brownmillerite-like model involving ordered vacancies and alternating octahedral and tetrahedral coordination at the metal sites, gives a better description of the local structure out to 5 Å. A remarkable phenomenon determined by neutron diffraction in Sr2Fe1.5Cr0.5O5 is the occurrence of a long-range G-type antiferromagnetic ordering with Tc ≈ 565 K because cubic oxygen-deficient perovskites with B-site disorder usually do not undergo transitions to magnetically ordered states. The observation of long-range antiferromagnetic order and the Tc value are in accordance with previous Mössbauer spectroscopic studies. |
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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 |
Easton, Pa |
Editor |
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Language |
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Wos |
000300466300079 |
Publication Date |
2012-01-30 |
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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 |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.857 |
Times cited |
12 |
Open Access |
|
|
|
Notes |
Fwo |
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:95039 |
Serial |
3828 |
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Permanent link to this record |
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Author |
Compernolle, T.; Van Passel, S.; Weyens, N.; Vangronsveld, J.; Lebbe, L.; Thewys, T. |
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Title |
Groundwater remediation and the cost effectiveness of phytoremediation |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
International Journal Of Phytoremediation |
Abbreviated Journal |
Int J Phytoremediat |
|
|
Volume |
14 |
Issue |
9 |
Pages |
861-877 |
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|
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
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|
Abstract |
In 1999, phytoremediation was applied at the site of a Belgian car factory to contain two BTEX plumes. This case study evaluates the cost effectiveness of phytoremediation compared to other remediation options, applying a tailored approach for economic evaluation. Generally, when phytoremediation is addressed as being cost effective, the cost effectiveness is only determined on an average basis. This study however, demonstrates that an incremental analysis may provide a more nuanced conclusion. When the cost effectiveness is calculated on an average basis, in this particular case, the no containment strategy (natural attenuation) has the lowest cost per unit mass removed and hence, should be preferred. However, when the cost effectiveness is determined incrementally, no containment should only be preferred if the value of removing an extra gram of contaminant mass is lower than 320. Otherwise, a permeable reactive barrier should be adopted. A similar analysis is provided for the effect determined on the basis of remediation time. Phytoremediation is preferred compared to no containment if reaching the objective one year earlier is worth 7 000. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000304914700004 |
Publication Date |
2012-06-07 |
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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 |
1522-6514 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
1.77 |
Times cited |
12 |
Open Access |
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|
Notes |
; ; |
Approved |
Most recent IF: 1.77; 2012 IF: 1.179 |
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Call Number |
UA @ admin @ c:irua:129862 |
Serial |
6206 |
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Permanent link to this record |
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Author |
De Schepper, E.; Van Passel, S.; Manca, J.; Thewys, T. |
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Title |
Combining photovoltaics and sound barriers : a feasibility study |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Renewable Energy |
Abbreviated Journal |
Renew Energ |
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Volume |
46 |
Issue |
|
Pages |
297-303 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
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Abstract |
In the light of global warming, renewables such as solar photovoltaics (PV) are important to decrease greenhouse gas emissions. An important issue regarding implementation of solar panels on large scale, is the limited available area. Therefore, it can be interesting to combine PV with alternative applications, as a ways of not requiring “additional” space. One example is a photovoltaic noise barrier (PVNB), where a noise barrier located along a highway or railway is used as substructure for PV modules. Even though a PVNB is not a novel concept, the absence of economic assessments in literature can be a barrier to their wider implementation. In this paper, a feasibility study of a PVNB in Belgium is conducted, using a cost benefit analysis including a Monte Carlo sensitivity analysis. Besides purely economic aspects, also ecological benefits are monetized. The sensitivity analysis indicates that the ecological benefit of noise reduction, which is valuated using a noise sensitivity depreciation index applied to real estate prices, is of major importance in determining the net present value of the case study. On the contrary, the impact of reducing CO2 emissions seems to be negligible when expressed in monetary terms. The results suggest that the PVNB as a whole and also its separate components -.e. the PV array and the noise barrier can be profitable projects, when ecological benefits are included. (C) 2012 Elsevier Ltd. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000305169400036 |
Publication Date |
2012-04-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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|
ISSN |
0960-1481 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
4.357 |
Times cited |
12 |
Open Access |
|
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|
Notes |
; ; |
Approved |
Most recent IF: 4.357; 2012 IF: 2.989 |
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Call Number |
UA @ admin @ c:irua:127555 |
Serial |
6170 |
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Permanent link to this record |
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Author |
Kishore, V.V.R.; Čukarić, N.; Partoens, B.; Tadić, M.; Peeters, F.M. |
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Title |
Hole subbands in freestanding nanowires : six-band versus eight-band k.p modelling |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
13 |
Pages |
135302-135302,10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The electronic structure of GaAs, InAs and InSb nanowires is studied using the six-band and the eight-band k.p models. The effect of the different Luttinger-like parameters (in the eight-band model) on the hole band structure is investigated. Although GaAs nanostructures are often treated within a six-band model because of the large bandgap, it is shown that an eight-band model is necessary for a correct description of its hole spectrum. The camel-back structure usually found in the six-band model is not always present in the eight-band model. This camel-back structure depends on the interaction between light and heavy holes, especially the ones with opposite spin. The latter effect is less pronounced in an eight-band model, but could be very sensitive to the Kane inter-band energy (E-P) value. |
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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 |
000302120100007 |
Publication Date |
2012-03-06 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
13 |
Open Access |
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|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), Belgian Science Policy (IAP) and the Ministry of Education and Science of Serbia. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:97763 |
Serial |
1479 |
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Permanent link to this record |
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Author |
Dixon, E.; Hadermann, J.; Hayward, M.A. |
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Title |
Structures and magnetism of La1-xSrxMnO3-(0.5+x)/2 (0.67\leq x\leq1) phases |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
24 |
Issue |
8 |
Pages |
1486-1495 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Topotactic reduction of La1-xSrxMnO3 (0.67 <= x <= 1) phases with sodium hydride yields a series of isoelectronic materials of composition La1-xSrxMnO3-(0.5+x)/2. Lanthanum rich members of the series (0.67 <= x <= 0.83) adopt anion deficient perovskite structures with a 6-layer -OTOOT'O- stacking sequence of sheets of octahedra/square-based pyramids (O) and sheets of tetrahedra (T). The strontium rich members of the series (0.83 <= x <= 1) incorporate “step defects” into this 6-layer structure in which the OTOOT'O stacking sequence is converted into either OOTOOT' or TOOT'OO at a defect plane which runs perpendicular to the [201] lattice plane. The step defects appear to provide a mechanism to relieve lattice strain and accommodate additional anion deficiency in phases with x > 0.83. Magnetization and neutron diffraction data indicate La1-xSrxMnO3-(0.5+x)/2 phases adopt antiferromagnetically ordered states at low-temperature in which the ordered arrangement of magnetic spins is incommensurate with the crystallographic lattice. |
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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 |
000303092300011 |
Publication Date |
2012-03-28 |
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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 |
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 |
13 |
Open Access |
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|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
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Call Number |
UA @ lucian @ c:irua:98253 |
Serial |
3318 |
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Permanent link to this record |
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Author |
Charkin, D.O.; Urmanov, A.V.; Kazakov, S.M.; Batuk, D.; Abakumov, A.M.; Knöner, S.; Gati, E.; Wolf, B.; Lang, M.; Shevelkov, A.V.; Van Tendeloo, G.; Antipov, E.V.; |
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Title |
Synthesis, crystal structure, transport, and magnetic properties of novel ternary copper phosphides, A2Cu6P5(A = Sr, Eu) and EuCu4P3 |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
16 |
Pages |
8948-8955 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Three new ternary copper phosphides, Sr2Cu6P5, Eu2Cu6P5, and EuCu4P3, have been synthesized from the elements in evacuated silica capsules. Eu2Cu6P5 and Sr2Cu6P5 adopt the Ca2Cu6P5-type structure, while EuCu4P3 is isostructural to BaMg4Si3 and still remains the only representative of this structure type among the ternary Cu pnictides. All three materials show metallic conductivity in the temperature range 2 K <= T <= 290 K, with no indication for superconductivity. For Eu2Cu6P5 and EuCu4P3, long-range magnetic order was observed, governed by 4f local moments on the Eu atoms with predominant ferromagnetic interactions. While Eu2Cu6P5 shows a single ferromagnetic transition at T-C = 34 K, the magnetic behavior of EuCu4P3 is more complex, giving rise to three consecutive magnetic phase transitions at 70, 43, and 18 K. |
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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 |
Easton, Pa |
Editor |
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Language |
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Wos |
000307606200042 |
Publication Date |
2012-07-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.857 |
Times cited |
13 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:102217 |
Serial |
3453 |
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Permanent link to this record |
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Author |
Muñoz, W.A.; Covaci, L.; Peeters, F.M. |
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Title |
Tight-binding study of bilayer graphene Josephson junctions |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
86 |
Issue |
18 |
Pages |
184505-184507 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using highly efficient simulations of the tight-binding Bogoliubov-de-Gennes model, we solved self-consistently for the pair correlation and the Josephson current in a superconducting-bilayer graphene-superconducting Josephson junction. Different doping levels for the non-superconducting link are considered in the short- and long-junction regimes. Self-consistent results for the pair correlation and superconducting current resemble those reported previously for single-layer graphene except at the Dirac point, where remarkable differences in the proximity effect are found, as well as a suppression of the superconducting current in the long-junction regime. Inversion symmetry is broken by considering a potential difference between the layers and we found that the supercurrent can be switched if the junction length is larger than the Fermi length. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000310840400005 |
Publication Date |
2012-11-07 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
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|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:105149 |
Serial |
3661 |
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Permanent link to this record |
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Author |
Bittencourt, C.; Krüger, P.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Ewels, C.; Umek, P.; Guttmann, P. |
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Title |
Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
3 |
Issue |
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Pages |
789-797 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Recent advances in near-edge X-ray-absorption fine-structure spectroscopy coupled with transmission X-ray microscopy (NEXAFS-TXM) allow large-area mapping investigations of individual nano-objects with spectral resolution up to E/Delta E = 104 and spatial resolution approaching 10 nm. While the state-of-the-art spatial resolution of X-ray microscopy is limited by nanostructuring process constrains of the objective zone plate, we show here that it is possible to overcome this through close coupling with high-level theoretical modelling. Taking the example of isolated bundles of hydrothermally prepared sodium titanate nanotubes ((Na,H)TiNTs) we are able to unravel the complex nanoscale structure from the NEXAFS-TXM data using multichannel multiple-scattering calculations, to the extent of being able to associate specific spectral features in the O K-edge and Ti L-edge with oxygen atoms in distinct sites within the lattice. These can even be distinguished from the contribution of different hydroxyl groups to the electronic structure of the (Na,H)TiNTs. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000311482400001 |
Publication Date |
2012-11-23 |
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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 |
2190-4286; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.127 |
Times cited |
13 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.127; 2012 IF: 2.374 |
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Call Number |
UA @ lucian @ c:irua:105140 |
Serial |
3684 |
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Permanent link to this record |
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Author |
Berdiyorov, G.R.; Hernández-Nieves, A.D.; Milošević, M.V.; Peeters, F.M.; Dominguez, D. |
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Title |
Flux-quantum-discretized dynamics of magnetic flux entry, exit, and annihilation in current-driven mesoscopic type-I superconductors |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
9 |
Pages |
092502-092502,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study nonlinear flux dynamics in a current-carrying type-I superconductor. The stray magnetic field of the current induces the intermediate state, where nucleation of flux domains is discretized to a single fluxoid at a time, while their final shape (tubular or laminar), size, and nucleation rate depend on applied current and edge conditions. The current induces opposite flux domains on opposite sides of the sample, and subsequently drives them to annihilation-which is also discretized, as a sequence of vortex-antivortex pairs. The discretization of both nucleation and annihilation leaves measurable traces in the voltage across the sample and in locally probed magnetization. The reported dynamic phenomena thus provide an unambiguous proof of a flux quantum being the smallest building block of the intermediate state in type-I superconductors. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000301183000002 |
Publication Date |
2012-03-07 |
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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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
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|
Notes |
; This work was supported by the Belgian Science Policy (IAP), the Flemish Science Foundation (FWO-Vl), and the collaborative project FWO-MINCyT (Project No. FW/08/01). G. R. B. and A. D. H acknowledge support from FWO-Vl. A. D. H. and D. D. acknowledge support from CONICET, CNEA, and ANPCyT (Grant No. PICT07-824). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:97180 |
Serial |
1243 |
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Permanent link to this record |
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Author |
Özen, M.; Mertens, M.; Luyten, J.; Snijkers, F.; d' Hondt, H.; Cool, P. |
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Title |
Hydrothermal synthesis of carbonate-free submicron-sized barium titanate from an amorphous precursor : synthesis and characterization |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Ceramics international |
Abbreviated Journal |
Ceram Int |
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Volume |
38 |
Issue |
1 |
Pages |
619-625 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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Abstract |
In this paper, the amorphous barium titanate precursor was prepared by the peroxo-hydroxide method and post-treated by various drying procedures, such as: room temperature drying, room temperature vacuum drying and vacuum drying at 50 degrees C. The objective in the latter two treatments was to increase the Ti-O-Ba bonds of the precursor. The post-treated precursors were compared with the untreated (i.e., 'wet') precursor. Also, a barium titanate precursor was prepared by an alkoxide route. Afterwards, the precursors were hydrothermally treated at 200 degrees C in a 10 M NaOH solution. Vacuum drying of the precursor seemingly promoted the formation of Ti-O-Ti bonds in the hydrothermal end-product. The low Ba:Ti ratio (0.66) of the alkoxide-route prepared precursor lead to a multi-phase hydrothermal product with BaTiO(3) as the main phase. In contrast, phase pure BaTiO(3), i.e. without BaCO(3) contamination, was obtained for the precursor which was dried at room temperature. Cube-shaped and highly crystalline BaTiO(3) particles were observed by electron microscopy for the hydrothermally treated peroxo-hydroxide-route prepared precursor. (C) 2011 Elsevier Ltd and Techna Group S.r.l. All rights reserved. |
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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 |
Barking |
Editor |
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Language |
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Wos |
000298766900083 |
Publication Date |
2011-08-02 |
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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 |
0272-8842; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.986 |
Times cited |
14 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 2.986; 2012 IF: 1.789 |
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Call Number |
UA @ lucian @ c:irua:96263 |
Serial |
1541 |
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Permanent link to this record |
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Author |
Euán-Díaz, E.C.; Misko, V.R.; Peeters, F.M.; Herrera-Velarde, S.; Castaneda-Priego, R. |
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Title |
Single-file diffusion in periodic energy landscapes : the role of hydrodynamic interactions |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
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Volume |
86 |
Issue |
3Part 1 |
Pages |
031123 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report on the dynamical properties of interacting colloids confined to one dimension and subjected to external periodic energy landscapes. We particularly focus on the influence of hydrodynamic interactions on the mean-square displacement. Using Brownian dynamics simulations, we study colloidal systems with two types of repulsive interparticle interactions, namely, Yukawa and superparamagnetic potentials. We find that in the homogeneous case, hydrodynamic interactions lead to an enhancement of the particle mobility and the mean-square displacement at long times scales as t(alpha), with alpha = 1/2 + epsilon and epsilon being a small correction. This correction, however, becomes much more important in the presence of an external field, which breaks the homogeneity of the particle distribution along the line and, therefore, promotes a richer dynamical scenario due to the hydrodynamical coupling among particles. We provide here the complete dynamical scenario in terms of the external potential parameters: amplitude and commensurability. |
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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 |
Woodbury (NY) |
Editor |
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Language |
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Wos |
000308873500002 |
Publication Date |
2012-09-21 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.366 |
Times cited |
14 |
Open Access |
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Notes |
; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), and PIFI 3.4-PROMEP and CONACyT (Grant Nos. 61418/2007 and 102339/2008, Ph.D. Scholarship No. 230171/ 2010). ; |
Approved |
Most recent IF: 2.366; 2012 IF: 2.313 |
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Call Number |
UA @ lucian @ c:irua:101840 |
Serial |
3021 |
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Permanent link to this record |
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Author |
Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D. |
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Title |
Stability of Sb-Te layered structures : first-principles study |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
14 |
Pages |
144114-144114,8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Using an effective one-dimensional cluster expansion in combination with first-principles electronic structure calculations we have studied the energetics and electronic properties of Sb-Te layered systems. For a Te concentration between 0 and 60 at. % an almost continuous series of metastable structures is obtained consisting of consecutive Sb bilayers next to consecutive Sb2Te3 units, with the general formula (Sb-2)(n)(Sb2Te3)(m) (n, m = 1,2, ... ). Between 60 and 100 at.% no stable structures are found. We account explicitly for the weak van derWaals bonding between Sb bilayers and Sb2Te3 units by using a recently developed functional, which strongly improves the interlayer bonding distances. At T = 0 K, no evidence is found for the existence of two separate single-phase regions delta and gamma and a two-phase region delta + gamma. Metastable compounds with a Te concentration between 0 and 40 at. % are semimetallic, whereas compounds with a Te concentration between 50 and 60 at. % are semiconducting. Compounds with an odd number of Sb layers are metallic and have a much higher formation energy than those with an even number of consecutive Sb layers, thereby favoring the formation of Sb bilayers. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000303115400004 |
Publication Date |
2012-04-23 |
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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 |
|
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 |
14 |
Open Access |
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|
Notes |
Iwt; Fwo |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98255 |
Serial |
3129 |
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Permanent link to this record |
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Author |
Chernov, S.V.; Dobrovolsky, Y.A.; Istomin, S.Y.; Antipov, E.V.; Grins, J.; Svensson, G.; Tarakina, N.V.; Abakumov, A.M.; Van Tendeloo, G.; Eriksson, S.G.; Rahman, S.M.H.; |
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Title |
_Sr{2}GaScO5, Sr10Ga6Sc4O25, and SrGa0.75Sc0.25O2.5 : a play in the octahedra to tetrahedra ratio in oxygen-deficient perovskites |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
2 |
Pages |
1094-1103 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Three different perovskite-related phases were isolated in the SrGa(1-x)Sc(x)O(2.5) system: Sr(2)GaScO(5), Sr(10)Ga(6)Sc(4)O(25), and SrGa(0.75)Sc(0.25)O(2.5), Sr(2)GaScO(5) (x = 0.5) crystallizes in a brownrnillerite-type structure [space group (S.G.) Icmm, a = 5.91048(5) angstrom, b = 15.1594(1) angstrom, and c = 5.70926(4) angstrom] with complete ordering of Sc(3+) and Ga(3+) over octahedral and tetrahedral positions, respectively. The crystal structure of Sr(10)Ga(6)Sc(4)O(25) (x = 0.4) was determined by the Monte Carlo method and refined using a combination of X-ray, neutron, and electron diffraction data [S.G. I4(1)/a, a = 17.517(1) angstrom, c = 32.830(3) angstrom]. It represents a novel type of ordering of the B cations and oxygen vacancies in perovskites. The crystal structure of Sr(10)Ga(6)Sc(4)O(25) can be described as a stacking of eight perovskite layers along the c axis ...[-(Sc/Ga)O(1.6)-SrO(0.8)-(Sc/Ga)O(1.8)-SrO(0.8)-](2 center dot center dot center dot) Similar to Sr(2)GaScO(5), this structure features a complete ordering of the Sc(3+) and Ga(3+) cations over octahedral and tetrahedral positions, respectively, within each layer. A specific feature of the crystal structure of Sr(10)Ga(6)Sc(4)O(25) is that one-third of the tetrahedra have one vertex not connected with other Sc/Ga cations. Further partial replacement of Sc(3+) by Ga(3+) leads to the formation of the cubic perovskite phase SrGa(0.75)Sc(0.25)O(2.5) (x = 0.25) with a = 3.9817(4) angstrom. This compound incorporates water molecules in the structure forming SrGa(0.75)Sc(0.25)O(2.5)center dot xH(2)O hydrate, which exhibits a proton conductivity of similar to 2.0 x 10(-6) S/cm at 673 K. |
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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 |
Easton, Pa |
Editor |
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Language |
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Wos |
000299028800042 |
Publication Date |
2011-12-22 |
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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 |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
14 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:96229 |
Serial |
3559 |
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Permanent link to this record |
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Author |
Cooper, D.; Denneulin, T.; Barnes, J.-P.; Hartmann, J.-M.; Hutin, L.; Le Royer, C.; Béché, A.; Rouvière, J.-L. |
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Title |
Strain mapping with nm-scale resolution for the silicon-on-insulator generation of semiconductor devices by advanced electron microscopy |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
112 |
Issue |
|
Pages |
124505 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Strain engineering in the conduction channel is a cost effective method of boosting the performance in state-of-the-art semiconductor devices. However, given the small dimensions of these devices, it is difficult to quantitatively measure the strain with the required spatial resolution. Three different transmission electron microscopy techniques, high-angle annular dark field scanning transmission electron microscopy, dark field electron holography, and nanobeam electron diffraction have been applied to measure the strain in simple bulk and SOI calibration specimens. These techniques are then applied to different gate length SiGe SOI pFET devices in order to measure the strain in the conduction channel. For these devices, improved spatial resolution is required, and strain maps with spatial resolutions as good as 1 nm have been achieved. Finally, we discuss the relative advantages and disadvantages of using these three different techniques when used for strain measurement. |
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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 |
000312829400128 |
Publication Date |
2012-12-19 |
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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 |
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 |
14 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:136433 |
Serial |
4510 |
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Permanent link to this record |
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Author |
Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.; Costa Filho, R.N. |
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Title |
The electronic properties of graphene and graphene ribbons under simple shear strain |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
37 |
Pages |
375301 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A tight-binding model is used to study the energy band of graphene and graphene ribbon under simple shear strain. The ribbon consists of lines of carbon atoms in an armchair or zigzag orientation where a simple shear strain is applied in the x-direction keeping the atomic distances in the y-direction unchanged. Such modification in the lattice gives an energy band that differs in several aspects from the one without any shear and with pure shear. The changes in the spectrum depend on the line displacement of the ribbon, and also on the modified hopping parameter. It is also shown that this simple shear strain tunes the electronic properties of both graphene and graphene ribbon, opening and closing energy gaps for different displacements of the system. The modified density of states is also shown. |
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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 |
000308202700011 |
Publication Date |
2012-08-14 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
15 |
Open Access |
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Notes |
; This work was supported by CNPq (RNCF), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:101838 |
Serial |
1000 |
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Permanent link to this record |
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Author |
Vandebroek, M.; Belis, J.; Louter, C.; Van Tendeloo, G. |
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Title |
Experimental validation of edge strength model for glass with polished and cut edge finishing |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Engineering fracture mechanics |
Abbreviated Journal |
Eng Fract Mech |
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Volume |
96 |
Issue |
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Pages |
480-489 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In literature, the experimental validation of a glass edge strength model is lacking. Therefore, in this study, an edge strength model was established and validated. The short-term parameters of the edge strength model, i.e. the flaw geometry and depth, were determined by means of testing at a high stress rate. This was done for polished and cut edges. Next, the strength model, including subcritical crack growth, was established. Finally, the edge strength model was validated by the test results at a low stress rate. The assessed model was found to be slightly conservative, compared to the test results. |
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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 |
000313384300034 |
Publication Date |
2012-09-04 |
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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 |
0013-7944; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.151 |
Times cited |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.151; 2012 IF: 1.413 |
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Call Number |
UA @ lucian @ c:irua:105285 |
Serial |
1145 |
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Permanent link to this record |
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Author |
Zhang, Y.-R.; Xu, X.; Bogaerts, A.; Wang, Y.-N. |
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Title |
Fluid simulation of the phase-shift effect in hydrogen capacitively coupled plasmas: 2 : radial uniformity of the plasma characteristics |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
45 |
Issue |
1 |
Pages |
015203-015203,13 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A two-dimensional fluid model, including the full set of Maxwell equations, has been developed and applied to investigate the effect of a phase shift between two power sources on the radial uniformity of several plasma characteristics in a hydrogen capacitively coupled plasma. This study was carried out at various frequencies in the range 13.56200 MHz. When the frequency is low, at 13.56 MHz, the plasma density is characterized by an off-axis peak when both power sources are in-phase (phgr = 0), and the best radial uniformity is obtained at phgr = π. This trend can be explained because the radial nonuniformity caused by the electrostatic edge effect can be effectively suppressed by the phase-shift effect at a phase difference equal to π. When the frequency rises to 60 MHz, the plasma density profiles shift smoothly from edge-peaked over uniform to centre-peaked as the phase difference increases, due to the pronounced standing-wave effect, and the best radial uniformity is reached at phgr = 0.3π. At a frequency of 100 MHz, a similar behaviour is observed, except that the maximum of the plasma density moves again towards the radial edge at the reverse-phase case (phgr = π), because of the dominant skin effect. When the frequency is 200 MHz, the bulk plasma density increases significantly with increasing phase-shift values, and a better uniformity is obtained at phgr = 0.4π. This is because the density in the centre increases faster than at the radial edge as the phase difference rises, due to the increasing power deposition Pz in the centre and the decreasing power density Pr at the radial edge. As the phase difference increases to π, the maximum near the radial edge becomes obvious again. This is because the skin effect has a predominant influence on the plasma density under this condition, resulting in a high density at the radial edge. Moreover, the axial ion flux increases monotonically with phase difference, and exhibits similar profiles to the plasma density. The calculation results illustrate that the radial uniformity of the various plasma characteristics is strongly dependent on the applied frequency and the phase shift between both power sources, which is important to realize, for controlling the uniformity of the plasma etch and deposition processes. |
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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 |
000298290000012 |
Publication Date |
2011-12-12 |
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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 |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
15 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 2.588; 2012 IF: 2.528 |
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Call Number |
UA @ lucian @ c:irua:92852 |
Serial |
1231 |
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Permanent link to this record |
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Author |
van den Broek, W.; Van Aert, S.; van Dyck, D. |
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Title |
Fully automated measurement of the modulation transfer function of charge-coupled devices above the Nyquist frequency |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
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Volume |
18 |
Issue |
2 |
Pages |
336-342 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
The charge-coupled devices used in electron microscopy are coated with a scintillating crystal that gives rise to a severe modulation transfer function (MTF). Exact knowledge of the MTF is imperative for a good correspondence between image simulation and experiment. We present a practical method to measure the MTF above the Nyquist frequency from the beam blocker's shadow image. The image processing has been fully automated and the program is made public. The method is successfully tested on three cameras with various beam blocker shapes. |
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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, Mass. |
Editor |
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Language |
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Wos |
000302084700011 |
Publication Date |
2012-02-14 |
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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 |
1431-9276;1435-8115; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.891 |
Times cited |
15 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 1.891; 2012 IF: 2.495 |
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Call Number |
UA @ lucian @ c:irua:96557 |
Serial |
1297 |
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Permanent link to this record |
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Author |
Scarrozza, M.; Pourtois, G.; Houssa, M.; Heyns, M.; Stesmans, A. |
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Title |
Oxidation of the GaAs(001) surface : insights from first-principles calculations |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
19 |
Pages |
195307-195307,8 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
We performed a detailed investigation of the oxidation of the technologically relevant GaAs(001)-beta 2(2x4) surface via density functional calculations. The purpose is to gain insights on the atomistic mechanisms and local bondings that underlie the degradation of the surface properties once exposed to oxygen. The study comprises the adsorption of single O atoms, through the sampling of several adsorption sites, and the subsequent formation of the O adsorbate at increasing coverage by taking into account multiple-atom adsorption. Based on the evaluation of the energetics and the structural properties of the atomistic models generated, the results here reported delineate a consistent picture of the initial stage of the surface oxidation: (i) at low coverage, in the limit of single O insertions, oxygen is incorporated on the surface forming a twofold-bridging Ga-O-As bond; (ii) at increasing coverage, as multiple O atoms are involved, this is accompanied by the formation of a threefold-coordinated bond (with two Ga and one As atoms); (iii) the latter has important implications regarding the electronic properties of the adsorbate since this O bonding may result in the formation of As dangling bonds. Moreover, a clear trend of increased energy gain for the incorporation of neighboring O atoms compared to single O insertions indicates that the formation of oxide clusters is favored over a regime of uniform oxidation. Our findings provide a detailed description of the O bonding and stress the importance of modeling the adsorption of multiple O atoms for an accurate description of the surface oxidation. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000303755700006 |
Publication Date |
2012-05-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
15 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:99122 |
Serial |
2538 |
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Permanent link to this record |
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Author |
Bittencourt, C.; Hitchock, A.P.; Ke, X.; Van Tendeloo, G.; Ewels, C.P.; Guttmann, P. |
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Title |
X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Beilstein journal of nanotechnology |
Abbreviated Journal |
Beilstein J Nanotech |
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Volume |
3 |
Issue |
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Pages |
345-350 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
We demonstrate that near-edge X-ray-absorption fine-structure spectra combined with full-field transmission X-ray microscopy can be used to study the electronic structure of graphite flakes consisting of a few graphene layers. The flake was produced by exfoliation using sodium cholate and then isolated by means of density-gradient ultracentrifugation. An image sequence around the carbon K-edge, analyzed by using reference spectra for the in-plane and out-of-plane regions of the sample, is used to map and spectrally characterize the flat and folded regions of the flake. Additional spectral features in both π and σ regions are observed, which may be related to the presence of topological defects. Doping by metal impurities that were present in the original exfoliated graphite is indicated by the presence of a pre-edge signal at 284.2 eV. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000303243400001 |
Publication Date |
2012-04-25 |
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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 |
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Edition |
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|
|
ISSN |
2190-4286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.127 |
Times cited |
15 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.127; 2012 IF: 2.374 |
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Call Number |
UA @ lucian @ c:irua:97703 |
Serial |
3924 |
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Permanent link to this record |