Records |
Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Fabry-Pérot resonances in graphene microstructures: influence of a magnetic field |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
11 |
Pages |
115417-115417,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Fabry-Pérot resonances in the transmission through single and double, graphene-based barriers (of height V) and wells are investigated and their dependence on an applied perpendicular magnetic field. For rectangular barriers the conductance decreases with increasing magnetic field while the resonances weaken (become more pronounced) with increasing magnetic field for EF<V (EF>V). The position of the resonances exhibit a linear shift with magnetic field which move to lower (higher) energy for EF<V (EF>V). Compared to semielliptic- or Gaussian-shaped barriers they show a smaller number of resonances in the absence of a magnetic field and an overall lower conductance but the resonant structure is more pronounced. The conductance of asymmetric double barriers show two major regions of resonances while the symmetric ones show one, that of three asymmetric barriers three, and so on. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000281723100007 |
Publication Date |
2010-09-10 |
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 |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
74 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Canadian NSERC under Grant No. OGP0121756. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:84871 |
Serial |
1167 |
Permanent link to this record |
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Author |
Xu, T.; Nys, J.-P.; Addad, A.; Lebedev, O.I.; Urbieta, A.; Salhi, B.; Berthe, M.; Grandidier, B.; Stievenard, D. |
Title |
Faceted sidewalls of silicon nanowires: Au-induced structural reconstructions and electronic properties |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
11 |
Pages |
115403,1-115403,10 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Si nanowires with a ⟨111⟩ orientation, synthesized by vapor-liquid-solid process with low silane partial pressure reactant and gold as the catalyst, are known to exhibit sawtooth facets containing gold adsorbates. We report herein the study of the nanowire morphology by means of transmission electron microscopy and scanning tunneling microscopy. The nanowires consist of faceted sidewalls. The number of the sidewalls changes from 12 to 6 along the growth axis, giving rise to nanowires with an irregular hexagonal cross section at their base. The sidewalls are covered with Au-rich clusters. Their facets also exhibit atomic structures that reveal the presence of gold, resulting from the diffusion of gold during the growth. Based on these observations, the tapering of the nanowire is found to be related to two contributions: the reduction in the catalyst particle size during the growth and lateral overgrowth from the direct incorporation of Si species onto the nanowire sidewalls. Because the rearrangement of atoms at surfaces and interfaces might affect the growth kinetics, the trigonal symmetry as well as the higher lateral growth rate on the widest sidewalls are explained from the existence of an interfacial atomic structure with two inequivalent parts in the unit cell. Finally, spectroscopic measurements were performed on the major facets and revealed a metallic behavior at 77 K. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000276248800116 |
Publication Date |
2010-03-03 |
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 |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
42 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:82273 |
Serial |
1168 |
Permanent link to this record |
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Author |
Zelaya, E.; Schryvers, D. |
Title |
FCC surface precipitation in Cu-Zn-Al after low angle GA+ ion irradiation |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Materials transactions |
Abbreviated Journal |
Mater Trans |
Volume |
51 |
Issue |
12 |
Pages |
2177-2180 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The precipitation of a disordered FCC surface structure after low angle Ga+ ion irradiation during focused ion beam thinning of a B2 Cu-Zn-Al alloy with e/a=1.48 is reported. Conventional as well as high-resolution transmission electron microscopy techniques reveal FCC layers on both sides of the thinned sample. The occurrence of this structure is attributed to disordering and dezincification of the alloy resulting from the sputtering process during the irradiation. Changes in crystallographic sample orientation with respect to the incoming ion beam do not have a significant effect on the appearance of the FCC surface structure. |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
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Place of Publication |
Sendai |
Editor |
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Language |
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Wos |
000287390300009 |
Publication Date |
2010-11-25 |
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 |
|
ISSN |
1347-5320;1345-9678; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.713 |
Times cited |
2 |
Open Access |
|
Notes |
Bof; Fwo |
Approved |
Most recent IF: 0.713; 2010 IF: 0.787 |
Call Number |
UA @ lucian @ c:irua:85997 |
Serial |
1175 |
Permanent link to this record |
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Author |
Leenaerts, O.; Peelaers, H.; Hernández-Nieves, A.D.; Partoens, B.; Peeters, F.M. |
Title |
First-principles investigation of graphene fluoride and graphane |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
19 |
Pages |
195436,1-195436,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Different stoichiometric configurations of graphane and graphene fluoride are investigated within density-functional theory. Their structural and electronic properties are compared, and we indicate the similarities and differences among the various configurations. Large differences between graphane and graphene fluoride are found that are caused by the presence of charges on the fluorine atoms. A configuration that is more stable than the boat configuration is predicted for graphene fluoride. We also perform GW calculations for the electronic band gap of both graphene derivatives. These band gaps and also the calculated Youngs moduli are at variance with available experimental data. This might indicate that the experimental samples contain a large number of defects or are only partially covered with H or F. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000284399200004 |
Publication Date |
2010-11-18 |
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 |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
367 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-V1), the NOI-BOF of the University of Antwerp, the Belgian Science Policy (IAP), and the collaborative project FWO-MINCyT (Grant No. FW/08/01). A.D.H. also acknowledges support from ANPCyT (Grant No. PICT 2008-2236). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:86916 |
Serial |
1212 |
Permanent link to this record |
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Author |
Sankaran, K.; Pourtois, G.; Degraeve, R.; Zahid, M.B.; Rignanese, G.-M.; Van Houdt, J. |
Title |
First-principles modeling of intrinsic and extrinsic defects in \gamma-Al2O3 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
97 |
Issue |
21 |
Pages |
212906 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The electronic properties of a set of intrinsic and extrinsic point defects in gamma-Al2O3 are investigated using quasiparticle calculations within the G(0)W(0) approximation. We find that the electronic signature of atomic vacancies lie deep in the band gap, close to the top of the valence band edge. The introduction of C, Si, and N impurities induces defective levels that are located close to the conduction band edge and near the middle of the band gap of the oxide. The comparison with electrical measurements reveals that the energy levels of some of these defects match with the electronic fingerprint of the defects reported in gamma-Al2O3 based nonvolatile memories. (C) 2010 American Institute of Physics. [doi:10.1063/1.3507385] |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000284618300039 |
Publication Date |
2010-11-24 |
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 |
Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
Call Number |
UA @ lucian @ c:irua:105617 |
Serial |
1213 |
Permanent link to this record |
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Author |
Cao, S.; Somsen, C.; Croitoru, M.; Schryvers, D.; Eggeler, G. |
Title |
Focused ion beam/scanning electron microscopy tomography and conventional transmission electron microscopy assessment of Ni4Ti3 morphology in compression-aged Ni-rich Ni-Ti single crystals |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
Volume |
62 |
Issue |
6 |
Pages |
399-402 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
The size, morphology and configuration of Ni4Ti3 precipitates in a single-crystal NiTi alloy have been investigated by two-dimensional transmission electron microscopy-based image analysis and three-dimensional reconstruction from slice-and-view images obtained in a focused ion beam/scanning electron microscopy (FIB/SEM) dual-beam system. Average distances between the precipitates measured along the compression direction correlate well between both techniques, while particle shape and configuration data is best obtained from FIB/SEM. Precipitates form pockets of B2 of 0.54 ìm in the compression direction and 1 ìm perpendicular to the compression direction. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000275072700020 |
Publication Date |
2009-12-04 |
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 |
|
ISSN |
1359-6462; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.747 |
Times cited |
16 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 3.747; 2010 IF: 2.820 |
Call Number |
UA @ lucian @ c:irua:79817 |
Serial |
1246 |
Permanent link to this record |
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Author |
Silhanek, A.V.; Milošević, M.V.; Kramer, R.B.G.; Berdiyorov, G.R.; Vondel van de, J.; Luccas, R.F.; Puig, T.; Peeters, F.M.; Moshchalkov, V.V. |
Title |
Formation of stripelike flux patterns obtained by freezing kinematic vortices in a superconducting Pb film |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
104 |
Issue |
1 |
Pages |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We demonstrate experimentally and theoretically that the dissipative state of superconducting samples with a periodic array of holes at high current densities consists of flux rivers resulting from a short-range attractive interaction between vortices. This dynamically induced vortex-vortex attraction results from the migration of quasiparticles out of the vortex core (kinematic vortices). We have directly visualized the formation of vortex chains by scanning Hall probe microscopy after freezing the dynamic state by a field cooling procedure at a constant bias current. Similar experiments carried out in a sample without holes show no hint of flux river formation. We shed light on this nonequilibrium phenomena modeled by time-dependent Ginzburg-Landau simulations. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000273881900033 |
Publication Date |
2010-01-07 |
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 |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
60 |
Open Access |
|
Notes |
; This work was supported by Methusalem funding by the Flemish government, the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, and the ESF NES network. A. V. S., G. R. B., and J. V. d. V. acknowledge support from FWO-VI R. F. L. acknowledges support from I3P CSIC program and MAT2008-01022. ; |
Approved |
Most recent IF: 8.462; 2010 IF: 7.622 |
Call Number |
UA @ lucian @ c:irua:81009 |
Serial |
1265 |
Permanent link to this record |
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Author |
Silhanek, A.V.; Kramer, R.G.B.; van de Vondel, J.; Moshchalkov, V.V.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M.; Luccas, R.F.; Puig, T. |
Title |
Freezing vortex rivers |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
470 |
Issue |
19 |
Pages |
726-729 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We demonstrate experimentally and theoretically that the dissipative state at high current densities of superconducting samples with a periodic array of holes consist of flux rivers resulting from a short range attractive interaction between vortices. This dynamically induced vortexvortex attraction results from the migration of quasiparticles out of the vortex core. We have directly visualized the formation of vortex chains by scanning Hall microscopy after freezing the dynamic state by a field cooling procedure at constant bias current. Similar experiments carried out in a sample without holes show no hint of flux river formation. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000282454400004 |
Publication Date |
2010-03-08 |
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 |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
4 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 1.404; 2010 IF: 1.415 |
Call Number |
UA @ lucian @ c:irua:85032 |
Serial |
1278 |
Permanent link to this record |
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Author |
Goffin, A.-L.; Duquesne, E.; Raquez, J.-M.; Miltner, H.E.; Ke, X.; Alexandre, M.; Van Tendeloo, G.; van Mele, B.; Dubois, P. |
Title |
From polyester grafting onto POSS nanocage by ring-opening polymerization to high performance polyester/POSS nanocomposites |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
20 |
Issue |
42 |
Pages |
9415-9422 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Polyester-grafted polyhedral oligomeric silsesquioxane (POSS) nanohybrids selectively produced by ring-opening polymerization of ε-caprolactone and L,L-lactide (A.-L. Goffin, E. Duquesne, S. Moins, M. Alexandre, Ph. Dubois, Eur. Polym. Journal, 2007, 43, 4103) were studied as masterbatches by melt-blending within their corresponding commercial polymeric matrices, i.e., poly(ε-caprolactone) (PCL) and poly(L,L-lactide) (PLA). For the sake of comparison, neat POSS nanoparticles were also dispersed in PCL and PLA. The objective was to prepare aliphatic polyester-based nanocomposites with enhanced crystallization behavior, and therefore, enhanced thermo-mechanical properties. Wide-angle X-ray scattering and transmission electron microscopy attested for the dispersion of individualized POSS nanoparticles in the resulting nanocomposite materials only when the polyester-grafted POSS nanohybrid was used as a masterbatch. The large impact of such finely dispersed (grafted) nanoparticles on the crystallization behavior for the corresponding polyester matrices was noticed, as evidenced by differential scanning calorimetry analysis. Indeed, well-dispersed POSS nanoparticles acted as efficient nucleating sites, significantly increasing the crystallinity degree of both PCL and PLA matrices. As a result, a positive impact on thermo-mechanical properties was highlighted by dynamic mechanical thermal analysis. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000283264500017 |
Publication Date |
2010-06-03 |
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 |
0959-9428;1364-5501; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
42 |
Open Access |
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Notes |
Fwo; Iap-6 |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:85784 |
Serial |
1284 |
Permanent link to this record |
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Author |
Ke, X. |
Title |
From top-down to bottom-up : from carbon nanotubes to nanodevices |
Type |
Doctoral thesis |
Year |
2010 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
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Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
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Place of Publication |
Antwerpen |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:87408 |
Serial |
1289 |
Permanent link to this record |
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Author |
Tsirlin, A.A.; Nath, R.; Abakumov, A.M.; Shpanchenko, R.V.; Geibel, C.; Rosner, H. |
Title |
Frustrated square lattice with spatial anisotropy: crystal structure and magnetic properties of PbZnVO(PO4)2 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
17 |
Pages |
174424,1-174424,13 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Crystal structure and magnetic properties of the layered vanadium phosphate PbZnVO(PO4)2 are studied using x-ray powder diffraction, magnetization and specific-heat measurements, as well as band-structure calculations. The compound resembles AA′VO(PO4)2 vanadium phosphates and fits to the extended frustrated square-lattice model with the couplings J1, J1′ between nearest neighbors and J2, J2′ between next-nearest neighbors. The temperature dependence of the magnetization yields estimates of averaged nearest-neighbor and next-nearest-neighbor couplings, J̅ 1≃−5.2 K and J̅ 2≃10.0 K, respectively. The effective frustration ratio α=J̅ 2/J̅ 1 amounts to −1.9 and suggests columnar antiferromagnetic ordering in PbZnVO(PO4)2. Specific-heat data support the estimates of J̅ 1 and J̅ 2 and indicate a likely magnetic ordering transition at 3.9 K. However, the averaged couplings underestimate the saturation field, thus pointing to the spatial anisotropy of the nearest-neighbor interactions. Band-structure calculations confirm the identification of ferromagnetic J1, J1′ and antiferromagnetic J2, J2′ in PbZnVO(PO4)2 and yield (J1′−J1)≃1.1 K in excellent agreement with the experimental value of 1.1 K, deduced from the difference between the expected and experimentally measured saturation fields. Based on the comparison of layered vanadium phosphates with different metal cations, we show that a moderate spatial anisotropy of the frustrated square lattice has minor influence on the thermodynamic properties of the model. We discuss relevant geometrical parameters, controlling the exchange interactions in these compounds and propose a strategy for further design of strongly frustrated square-lattice materials. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000278141600082 |
Publication Date |
2010-05-25 |
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 |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:83384 |
Serial |
1294 |
Permanent link to this record |
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Author |
Ding, F.; Akopian, N.; Li, B.; Perinetti, U.; Govorov, A.; Peeters, F.M.; Bufon, C.C.; Deneke, C.; Chen, Y.H.; Rastelli, A.; Schmidt, O.G.; Zwiller, V. |
Title |
Gate controlled Aharonov-Bohm-type oscillations from single neutral excitons in quantum rings |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
7 |
Pages |
8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
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Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000280813100005 |
Publication Date |
2010-08-11 |
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 |
58 |
Open Access |
|
Notes |
; We acknowledge L. P. Kouwenhoven and Z. G. Wang for support, L. Wang, V. Fomin, S. Kiravittaya, M. Tadic, Wen-Hao Chang, I. Sellers, A. Avetisyan, and C. Pryor for fruitful discussions and the financial support of NWO (VIDI), the CAS-MPG program, the DFG (FOR730), BMBF (Grant No. 01BM459), NSFC (Grant No. 60625402), and Flemish Science Foundation (FWO-V1). Access to the TEM of B. Rellinghaus is acknowledged. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:83992 |
Serial |
1321 |
Permanent link to this record |
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Author |
Pogosov, W.V.; Misko, V.R.; Peeters, F.M. |
Title |
Geometry-induced localization of thermal fluctuations in ultrathin superconducting structures |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
5 |
Pages |
054523-054523,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Thermal fluctuations of the order parameter in an ultrathin triangular-shaped superconducting structure are studied near Tc, in zero applied field. We find that the order parameter is prone to much larger fluctuations in the corners of the structure as compared to its interior. This geometry-induced localization of thermal fluctuations is attributed to the fact that condensate confinement in the corners is characterized by a lower effective dimensionality, which favors stronger fluctuations. |
Address |
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Corporate Author |
|
Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000281294700006 |
Publication Date |
2010-08-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
|
Notes |
; This work was supported by the “Odysseus” Program of the Flemish government, FWO-Vl, and the Belgian Science Policy (IAP). W. V. P. acknowledges supports from the RFBR [Project No. 09-02-00248] and the “Dynasty Foundation.” ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:84470 |
Serial |
1334 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Vagov, A.; Peeters, F.M. |
Title |
Giant drop in the Bardeen-Cooper-Schrieffer coherence length induced by quantum size effects in superconducting nanowires |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
10 |
Pages |
104524-104524,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The BCS coherence length in low-dimensional superconductors is dramatically modified by quantum-size effects. In particular, for nanowires made of conventional superconducting materials, we show that the longitudinal zero-temperature coherence length exhibits width-dependent drops by 23 orders of magnitude each time when the bottom of one of single-electron subbands formed due to the transverse quantization of electron motion is situated in a close vicinity to the Fermi level. This phenomenon has strong similarities to the well-known BCS-BEC (Bose-Einstein condensation) crossover in ultracold fermionic condensates but with an important exception: it is driven by the transverse quantization of the electron motion rather than by the externally controlled strength of the fermion-fermion interaction. |
Address |
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Corporate Author |
|
Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000282269600005 |
Publication Date |
2010-09-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
29 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-network: INSTANS. M. D. C. acknowledges support from the Alexander von Humboldt Foundation. A. A. S. thanks R. G. Mints, W. V. Pogosov, D. Y. Vodolazov, A. Perali, and A. Bianconi for fruitful discussions. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:85419 |
Serial |
1337 |
Permanent link to this record |
|
|
|
Author |
Amin-Ahmadi, B.; Aashuri, H. |
Title |
Globular structure of M2 high speed steel by thermomechanical treatment in the semisolid state |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Steel research international |
Abbreviated Journal |
Steel Res Int |
Volume |
81 |
Issue |
5 |
Pages |
381-386 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The globular structure of M2 high speed steel in the rolled – annealed and as cast conditions was investigated in the semisolid state. Metallographic observations resulted in globular austenite particles that were surrounded by a liquid phase. Dissolution of various carbides in the austenite phase at semisolid temperatures led to grain boundary liquation and formation of near-spherical solid grains in a liquid matrix. Therefore, at the semisolid state, the solid particles were free from carbides. MC- type and M6C- type eutectic carbides re- precipitated at the grain boundaries during cooling of the samples from the semisolid temperature. The variation of shape factor versus holding time and holding temperature was examined. A transition value for shape factor changes in high speed steels was achieved. The growth rate constants of the Ostwald ripening and the coalescence mechanisms were calculated by using the experimentally determined rate constant. It was observed that less liquid droplets were enclosed inside the solid particles compared with non-ferrous alloys. Besides, it has been shown that at high solid fraction, the Ostwald ripening mechanism plays a prominent role in the coarsening phenomenon in comparison with the coalescence mechanism. Grains can rotate and arrange low misorientation with each other at high liquid contents, therefore low energetic grain boundaries form between these grains. These grain boundaries play an important role in the coalescence mechanism. |
Address |
|
Corporate Author |
|
Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
|
Publisher |
Verlag Stahleisen |
Place of Publication |
Düsseldorf |
Editor |
|
Language |
|
Wos |
000278292200007 |
Publication Date |
2010-05-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1611-3683;1869-344X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.235 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.235; 2010 IF: 0.455 |
Call Number |
UA @ lucian @ c:irua:122047 |
Serial |
1347 |
Permanent link to this record |
|
|
|
Author |
Neek-Amal, M.; Peeters, F.M. |
Title |
Graphene nanoribbons subjected to axial stress |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
8 |
Pages |
085432-085432,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Atomistic simulations are used to study the bending of rectangular graphene nanoribbons subjected to axial stress both for free boundary and supported boundary conditions. The shapes of the deformations of the buckled graphene nanoribbons, for small values of the stress, are sine waves where the number of nodal lines depend on the longitudinal size of the system and the applied boundary condition. The buckling strain for the supported boundary condition is found to be independent of the longitudinal size and estimated to be 0.86%. From a calculation of the free energy at finite temperature we find that the equilibrium projected two-dimensional area of the graphene nanoribbon is less than the area of a flat sheet. At the optimum length the boundary strain for the supported boundary condition is 0.48%. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000281065100007 |
Publication Date |
2010-08-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
92 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:84583 |
Serial |
1373 |
Permanent link to this record |
|
|
|
Author |
Afanasov, I.M.; Shornikova, O.N.; Kirilenko, D.A.; Vlasov, I.I.; Zhang, L.; Verbeeck, J.; Avdeev, V.V.; Van Tendeloo, G. |
Title |
Graphite structural transformations during intercalation by HNO3 and exfoliation |
Type |
L1 Letter to the editor |
Year |
2010 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
48 |
Issue |
6 |
Pages |
1862-1865 |
Keywords |
L1 Letter to the editor; Electron microscopy for materials research (EMAT) |
Abstract |
Expandable graphite of two types was synthesized by (1) hydrolysis of graphite nitrate of II stage and (2) anodic polarization of graphite in 60% HNO3. Exfoliated graphite samples were produced by thermal shock of expandable graphite samples in air at 900 °C. A comparative study of microstructural distinctions of both expandable and exfoliated graphite samples was carried out using X-ray diffraction, Raman spectroscopy, electron energy loss spectroscopy and high resolution transmission electron microscopy. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000276132800021 |
Publication Date |
2010-02-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
43 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.337; 2010 IF: 4.896 |
Call Number |
UA @ lucian @ c:irua:82315UA @ admin @ c:irua:82315 |
Serial |
1379 |
Permanent link to this record |
|
|
|
Author |
Milošević, M.V.; Gillijns, W.; Silhanek, A.V.; Libál, A.; Peeters, F.M.; Moshchalkov, V.V. |
Title |
Guided nucleation of superconductivity on a graded magnetic substrate |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
96 |
Issue |
3 |
Pages |
032503,1-032503,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We demonstrate the controlled spatial nucleation of superconductivity in a thin film deposited on periodic arrays of ferromagnetic dots with gradually increasing diameter. The perpendicular magnetization of the dots induces vortex-antivortex molecules in the sample, with the number of (anti)vortices increasing with magnet size. The resulting gradient of antivortex density between the dots predetermines local nucleation of superconductivity in the sample as a function of the applied external field and temperature. In addition, the compensation between the applied magnetic field and the antivortices results in an unprecedented enhancement of the critical temperature. |
Address |
|
Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000273890500034 |
Publication Date |
2010-01-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
15 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-NES program. W. G., A. V. S., and A. L. acknowledge individual support from FWO-Vlaanderen. ; |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
Call Number |
UA @ lucian @ c:irua:81504 |
Serial |
1400 |
Permanent link to this record |
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|
|
Author |
Ao, Z.M.; Peeters, F.M. |
Title |
High-capacity hydrogen storage in Al-adsorbed graphene |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
20 |
Pages |
205406,1-205406,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A high-capacity hydrogen storage mediumAl-adsorbed grapheneis proposed based on density-functional theory calculations. We find that a graphene layer with Al adsorbed on both sides can store hydrogen up to 13.79 wt % with average adsorption energy −0.193 eV/H2. Its hydrogen storage capacity is in excess of 6 wt %, surpassing U. S. Department of Energy (DOEs) target. Based on the binding-energy criterion and molecular-dynamics calculations, we find that hydrogen storage can be recycled at near ambient conditions. This high-capacity hydrogen storage is due to the adsorbed Al atoms that act as bridges to link the electron clouds of the H2 molecules and the graphene layer. As a consequence, a two-layer arrangement of H2 molecules is formed on each side of the Al-adsorbed graphene layer. The H2 concentration in the hydrogen storage medium can be measured by the change in the conductivity of the graphene layer. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000278144500082 |
Publication Date |
2010-05-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
219 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:83386 |
Serial |
1422 |
Permanent link to this record |
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|
|
Author |
Razdobarin, A.G.; Mukhin, E.E.; Semenov, V.V.; Yu.Tolstyakov, S.; Kochergin, M.M.; Kurskiev, G.S.; Podushnikova, K.A.; Kirilenko, D.A.; Sitnikova, A.A.; Gorodetsky, А.Е.; Bukhovets, V.L.; Zalavutdinov, R.K.; Zakharov, А.P.; Arkhipov, I.I.; Voitsenya, V.S.; Bondarenko, V.N.; Konovalov, V.G.; Ryzhkov, I.V.; |
Title |
High reflective mirrors for in-vessel applications in ITER |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Nuclear instruments and methods in physics research : A: accelerators, spectrometers, detectors and associated equipment |
Abbreviated Journal |
Nucl Instrum Meth A |
Volume |
623 |
Issue |
2 |
Pages |
809-811 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The structure and surface morphology of aluminum and silver mirrors covered with protective dielectric oxide layer were studied by means of TEM and SEM. The presence of needle-like pores throughout the thickness of the ZrO(2) film and bubble-like pores in Al(2)O(3) was observed. The test for resistivity to deuterium ion bombardment shows that the exposition to a fluence of similar to 2 x 10(20) ions/cm(2) with the ion energy of 40-50 eV results in appearance of blisters on the surface of mirrors covered wit h Al(2)O(3). For the mirrors protected with ZrO(2) no noticeable changes in surface morphology and reflectivity were found even after order of magnitude higher ion fluence. The effect of different porous structures on blistering phenomena is discussed. (C) 2010 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
Elsevier Science |
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000284343600041 |
Publication Date |
2010-04-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0168-9002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.362 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.362; 2010 IF: 1.142 |
Call Number |
UA @ lucian @ c:irua:95545 |
Serial |
1442 |
Permanent link to this record |
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|
|
Author |
Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. |
Title |
Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
Volume |
10 |
Issue |
4 |
Pages |
2011-2018 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000276234500080 |
Publication Date |
2010-03-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1528-7483;1528-7505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.055 |
Times cited |
75 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
Call Number |
UA @ lucian @ c:irua:82311 |
Serial |
1472 |
Permanent link to this record |
|
|
|
Author |
Chen, Y.; Shanenko, A.A.; Peeters, F.M. |
Title |
Hollow nanocylinder: multisubband superconductivity induced by quantum confinement |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
13 |
Pages |
134523-134523:11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Quantization of the transverse electron motion in high-quality superconducting metallic nanowires and nanofilms results in the formation of well-distinguished single-electron subbands. They shift in energy with changing thickness, which is known to cause quantum-size superconducting oscillations. The formation of multiple subbands results in a multigap structure induced by the interplay between quantum confinement and Andreev mechanism. We investigate multisubband superconductivity in a hollow nanocylinder by numerically solving the Bogoliubov-de Gennes equations. When changing the inner radius and thickness of the hollow nanocylinder, we find a crossover from an irregular pattern of quantum-size superconducting oscillations, typical of nanowires, to an almost regular regime, specific for superconducting nanofilms. At this crossover the multigap structure becomes degenerate. The ratio of the critical temperature to the energy gap increases and approaches its bulk value while being reduced by 20-30% due to Andreev-type states driven by quantum confinement in the irregular regime. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000277207900098 |
Publication Date |
2010-04-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles Programme, Belgian States, Belgian Science Policy (IAP) and the ESF-AQDJJ network. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:95623 |
Serial |
1481 |
Permanent link to this record |
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|
|
Author |
Malo, S.; Lepoittevin, C.; Pérez, O.; Hébert, S.; Van Tendeloo, G.; Hervieu, M. |
Title |
Incommensurate crystallographic shear structures and magnetic properties of the cation deficient perovskite (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
22 |
Issue |
5 |
Pages |
1788-1797 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The origin of the incommensurability in the crystallographic shear (CS) structure of the ferri-Manganite (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29, related to the cation deficient perovskite, has been determined by careful analysis of the boundaries between the two variants constituting the phasoid. High Resolution Electron Microscopy/HAADF-STEM images allow the structural mechanisms to be understood through the presence of structural units common to both phases, responsible of the incommensurate character observed in the electron diffraction patterns. The structural analysis allows for identifying different types of CS phases in the Pb−Sr−Fe(Mn)−O diagram and shows that the stabilization of the six-sided tunnels requires a higher A/B cationic ratio. A description of these phases is proposed through simple structural building units (SBU), based on chains of octahedra bordered by two pyramids. The (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29 CS compound exhibits a strong antiferromagnetic and insulating behavior, similar to the Fe-2201 and terrace ferrites but differs by the presence of a hysteresis, with a small coercive field. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000274929000025 |
Publication Date |
2010-01-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
6 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
Call Number |
UA @ lucian @ c:irua:81800 |
Serial |
1593 |
Permanent link to this record |
|
|
|
Author |
Nistor, S.V.; Stefan, M.; Nistor, L.C.; Goovaerts, E.; Van Tendeloo, G. |
Title |
Incorporation and localization of substitutional Mn2+ ions in cubic ZnS quantum dots |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue |
3 |
Pages |
035336,1-035336,6 |
Keywords |
A1 Journal article; Nanostructured and organic optical and electronic materials (NANOrOPT); Electron microscopy for materials research (EMAT) |
Abstract |
Multifrequency electron paramagnetic resonance (EPR) and high resolution transmission electron microscopy (HRTEM) investigations were performed on small (2 nm) cubic ZnS nanocrystals (quantum dotsQDs) doped with 0.2% mol Mn2+, self-assembled into a mesoporous structure. The EPR data analysis shows that the substitutional Mn2+ ions are localized at Zn2+ sites subjected to a local axial lattice distortion, resulting in the observed zero-field-splitting parameter |D|=41×10−4 cm−1. The local distortion is attributed to the presence in the second shell of ligands of a stacking fault or twin, which alters the normal stacking sequence of the cubic structure. The HRTEM results confirm the presence of such extended planar defects in a large percentage of the investigated QDs, which makes possible the proposed substitutional Mn2+ impurity ions localization model. Based on these results it is suggested that the high doping levels of Mn2+ ions observed in cubic ZnS and possible in other II-VI semiconductor QDs prepared at low temperatures can be explained by the assistance of the extended lattice defects in the impurities incorporation. |
Address |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000277970900007 |
Publication Date |
2010-01-29 |
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 |
55 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:83649 |
Serial |
1597 |
Permanent link to this record |
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Author |
Cortes-Gil, R.; Parker, D.R.; Pitcher, M.J.; Hadermann, J.; Clarke, S.J. |
Title |
Indifference of superconductivity and magnetism to size-mismatched cations in the layered iron arsenides Ba1-xNaxFe2As2 |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
22 |
Issue |
14 |
Pages |
4304-4311 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The evolution of the structure, magnetic ordering, and superconductivity in the series Ba(1-x)Na(x)Fe(2)As(2) is reported up to the limiting Na-rich composition with x = 0.6; the more Na-rich compositions are unstable at high temperatures with respect to competing phases. The magnetic and superconducting behaviors of the Bai,Na,Fe,As, members are similar to those of the betterinvestigated Ba(1-x)Na(x)Fe(2)As(2) analogues. This is evidently a consequence of the quantitatively similar evolution of the structure of the FeAs layers in the two series. In Ba(1-x)Na(x)Fe(2)As(2) antiferromagnetic order and an associated structural distortion are evident for x <= 0.35 and superconductivity is evident when x exceeds 0.2. For 0.4 <= x <= 0.6 bulk superconductivity is evident, and the long-range antiferromagnetically ordered state is completely suppressed. The maximum T(c) in the Ba(1-x)Na(x)Fe(2)As(2) series, as judged by the onset of diamagnetism, is 34K in Ba(0.6)Na(0.4)Fe(2)As(2). Despite the large mis-match in sizes between the two electropositive cations which separate the FeAs layers, there is no evidence for ordering of these cations on the length scale probed by electron diffraction. |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000280005300027 |
Publication Date |
2010-07-02 |
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 |
Impact Factor |
9.466 |
Times cited |
31 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
Call Number |
UA @ lucian @ c:irua:95594 |
Serial |
1601 |
Permanent link to this record |
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Author |
Martens, T.; Bogaerts, A.; Brok, W.J.M.; van Dijk, J. |
Title |
The influence of impurities on the performance of the dielectric barrier discharge |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
96 |
Issue |
9 |
Pages |
091501,1-091501,3 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this letter, we investigate the effect of various levels of nitrogen impurity on the electrical performance of an atmospheric pressure dielectric barrier discharge in helium. We illustrate the different current profiles that are obtained, which exhibit one or more discharge pulses per half cycle and evaluate their performance in ionizing the discharge and dissipating the power. It is shown that flat and broad current profiles perform the best in ionizing the discharge and use the least amount of power per generated charged particle. |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000275246200008 |
Publication Date |
2010-03-04 |
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 |
Impact Factor |
3.411 |
Times cited |
28 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
Call Number |
UA @ lucian @ c:irua:80944 |
Serial |
1624 |
Permanent link to this record |
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Author |
Burriel, M.; Casa-Cabanas, M.; Zapata, J.; Tan, H.; Verbeeck, J.; Solis, C.; Roqueta, J.; Skinner, S.J.; Kilner, J.A.; Van Tendeloo, G.; Santiso, J. |
Title |
Influence of the microstructure on the high-temperature transport properties of GdBaCo2O5.5+\delta epitaxial films |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
22 |
Issue |
19 |
Pages |
5512-5520 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Epitaxial thin films of GdBaCo2O5.5+δ (GBCO) grown by pulsed laser deposition have been studied as a function of deposition conditions. The variation in film structure, domain orientation, and microstructure upon deviations in the cation composition have been correlated with the charge transport properties of the films. The epitaxial GBCO films mainly consist of single- and double-perovskite regions that are oriented in different directions depending on the deposition temperature. Additionally, cobalt depletion induces the formation of a high density of stacking defects in the films, consisting of supplementary GdO planes along the c-axis of the material. The presence of such defects progressively reduces the electrical conductivity. The films closer to the stoichiometric composition have shown p-type electronic conductivity at high pO2 with values as high as 800 S/cm at 330 °C in 1 atm O2, and with a pO2 power dependence with an exponent as low as 1/25, consistent with the behavior reported for bulk GBCO. These values place GBCO thin films as a very promising material to be applied as cathodes in intermediate temperature solid oxide fuel cells. |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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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 |
000282471000013 |
Publication Date |
2010-09-20 |
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 |
Impact Factor |
9.466 |
Times cited |
17 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 9.466; 2010 IF: 6.400 |
Call Number |
UA @ lucian @ c:irua:85412UA @ admin @ c:irua:85412 |
Serial |
1648 |
Permanent link to this record |
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Author |
Li, Y.; Tan, H.; Lebedev, O.; Verbeeck, J.; Biermans, E.; Van Tendeloo, G.; Su, B.-L. |
Title |
Insight into the growth of multiple branched MnOOH nanorods |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
Volume |
10 |
Issue |
7 |
Pages |
2969-2976 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Multiple branched manganese oxide hydroxide (MnOOH) nanorods prepared by a hydrothermal process were extensively studied by transmission electron microscopy (TEM). A model of the branch formation is proposed together with a study of the interface structure. The sword-like tip plays a crucial role for the nanorods to form different shapes. Importantly, the branching occurs at an angle of around either 57 degrees or 123 degrees. Specifically, a (111) twin plane can only be formed at the interface with a 123 degrees angle. The interfaces formed with a 57 degrees angle usually contain edge dislocations. Electron energy loss spectroscopy (EELS) demonstrates that the whole crystal has a uniform chemical composition. Interestingly, an epitaxial growth of Mn3O4 at the radial surface was also observed under electron beam irradiation; this is because of the rough purification of the products. The proposed mechanism is expected to shed light on the branched/dendrite nanostructure growth and to provide opportunities for further novel nanomaterial structure growth and design. |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Place of Publication |
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Language |
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Wos |
000279422700027 |
Publication Date |
2010-06-08 |
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 |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.055 |
Times cited |
41 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
Call Number |
UA @ lucian @ c:irua:83886UA @ admin @ c:irua:83886 |
Serial |
1672 |
Permanent link to this record |
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Author |
Eckert, M.; Neyts, E.; Bogaerts, A. |
Title |
Insights into the growth of (ultra)nanocrystalline diamond by combined molecular dynamics and Monte Carlo simulations |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
Volume |
10 |
Issue |
7 |
Pages |
3005-3021 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, we present the results of combined molecular dynamics−Metropolis Monte Carlo (MD-MMC) simulations of hydrocarbon species at flat diamond (100)2 × 1 and (111)1 × 1 surfaces. The investigated species are considered to be the most important growth species for (ultra)nanocrystalline diamond ((U)NCD) growth. When applying the MMC algorithm to stuck species at monoradical sites, bonding changes are only seen for CH2. The sequence of the bond breaking and formation as put forward by the MMC simulations mimics the insertion of CH2 into a surface dimer as proposed in the standard growth model of diamond. For hydrocarbon species attached to two adjacent radical (biradical) sites, the MMC simulations give rise to significant changes in the bonding structure. For UNCD, the combinations of C3 and C3H2, and C3 and C4H2 (at diamond (100)2 × 1) and C and C2H2 (at diamond (111)1 × 1) are the most successful in nucleating new crystal layers. For NCD, the following combinations pursue the diamond structure the best: C2H2 and C3H2 (at diamond (100)2 × 1) and CH2 and C2H2 (at diamond (111)1 × 1). The different behaviors of the hydrocarbon species at the two diamond surfaces are related to the different sterical hindrances at the diamond surfaces. |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Place of Publication |
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Language |
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Wos |
000279422700032 |
Publication Date |
2010-05-25 |
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 |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.055 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
Call Number |
UA @ lucian @ c:irua:83065 |
Serial |
1675 |
Permanent link to this record |
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Author |
Arsoski, V.; Tadić, M.; Peeters, F.M. |
Title |
Interband optical properties of concentric type-I nanorings in a normal magnetic field |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Acta physica Polonica: A: general physics, solid state physics, applied physics |
Abbreviated Journal |
Acta Phys Pol A |
Volume |
117 |
Issue |
5 |
Pages |
733-737 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Two concentric two-dimensional GaAs/(Al,Ga)As nanorings in a normal magnetic field are theoretically studied. The single-band effective mass approximation is adopted for both the electron and the hole states, and the analytical solutions are given. We find that the electronic single particle states are arranged in pairs, which exhibit anticrossings and the orbital momentum transitions in the energy spectrum when magnetic field increases. Their period is essentially determined by the radius of the outer ring. The oscillator strength for interband transitions is strongly reduced close to each anticrossing. We show that an optical excitonic Aharonov-Bohm effect may occur in concentric nanorings. |
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Corporate Author |
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Thesis ![sorted by Thesis field, ascending order (up)](img/sort_asc.gif) |
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Publisher |
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Place of Publication |
Warszawa |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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 |
0587-4246 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.469 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 0.469; 2010 IF: 0.467 |
Call Number |
UA @ lucian @ c:irua:83377 |
Serial |
1690 |
Permanent link to this record |