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Records |
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Author |
Cambré, S.; Campo, J.; Beirnaert, C.; Verlackt, C.; Cool, P.; Wenseleers, W. |
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Title |
Asymmetric dyes align inside carbon nanotubes to yield a large nonlinear optical response |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
10 |
Issue |
10 |
Pages |
248-252 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Nanostructured and organic optical and electronic materials (NANOrOPT); Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Asymmetric dye molecules have unusual optical and electronic properties1, 2, 3. For instance, they show a strong second-order nonlinear optical (NLO) response that has attracted great interest for potential applications in electro-optic modulators for optical telecommunications and in wavelength conversion of lasers2, 3. However, the strong Coulombic interaction between the large dipole moments of these molecules favours a pairwise antiparallel alignment that cancels out the NLO response when incorporated into bulk materials. Here, we show that by including an elongated dipolar dye (p,p′-dimethylaminonitrostilbene, DANS, a prototypical asymmetric dye with a strong NLO response4) inside single-walled carbon nanotubes (SWCNTs)5, 6, an ideal head-to-tail alignment in which all electric dipoles point in the same sense is naturally created. We have applied this concept to synthesize solution-processible DANS-filled SWCNTs that show an extremely large total dipole moment and static hyperpolarizability (β0 = 9,800 × 10−30 e.s.u.), resulting from the coherent alignment of arrays of ∼70 DANS molecules. |
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Wos |
000350799700016 |
Publication Date |
2015-02-02 |
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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  |
1748-3387;1748-3395; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
38.986 |
Times cited |
46 |
Open Access |
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Notes |
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Approved |
Most recent IF: 38.986; 2015 IF: 34.048 |
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Call Number |
c:irua:125405 |
Serial |
158 |
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Author |
Godefroo, S.; Hayne, M.; Jivanescu, M.; Stesmans, A.; Zacharias, M.; Lebedev, O.I.; Van Tendeloo, G.; Moshchalkov, V.V. |
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Title |
Classification and control of the origin of photoluminescence from Si nanocrystals |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
3 |
Issue |
3 |
Pages |
174-178 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Silicon dominates the electronics industry, but its poor optical properties mean that III-V compound semiconductors are preferred for photonics applications. Photoluminescence at visible wavelengths was observed from porous Si at room temperature in 1990, but the origin of these photons (do they arise from highly localized defect states or quantum confinement effects?) has been the subject of intense debate ever since. Attention has subsequently shifted from porous Si to Si nanocrystals, but the same fundamental question about the origin of the photoluminescence has remained. Here we show, based on measurements in high magnetic fields, that defects are the dominant source of light from Si nanocrystals. Moreover, we show that it is possible to control the origin of the photoluminescence in a single sample: passivation with hydrogen removes the defects, resulting in photoluminescence from quantum-confined states, but subsequent ultraviolet illumination reintroduces the defects, making them the origin of the light again. |
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Wos |
000254743600017 |
Publication Date |
2008-03-02 |
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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 |
1748-3387;1748-3395; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
38.986 |
Times cited |
426 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 38.986; 2008 IF: 20.571 |
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Call Number |
UA @ lucian @ c:irua:102630 |
Serial |
373 |
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Author |
Talgorn, E.; Gao, Y.; Aerts, M.; Kunneman, L.T.; Schins, J.M.; Savenije, T.J.; van Huis, M.A.; van der Zant, H.S.J.; Houtepen, A.J.; Siebbeles, L.D.A. |
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Title |
Unity quantum yield of photogenerated charges and band-like transport in quantum-dot solids |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
6 |
Issue |
11 |
Pages |
733-739 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Solid films of colloidal quantum dots show promise in the manufacture of photodetectors and solar cells. These devices require high yields of photogenerated charges and high carrier mobilities, which are difficult to achieve in quantum-dot films owing to a strong electronhole interaction and quantum confinement. Here, we show that the quantum yield of photogenerated charges in strongly coupled PbSe quantum-dot films is unity over a large temperature range. At high photoexcitation density, a transition takes place from hopping between localized states to band-like transport. These strongly coupled quantum-dot films have electrical properties that approach those of crystalline bulk semiconductors, while retaining the size tunability and cheap processing properties of colloidal quantum dots. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Language |
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Wos |
000296737300012 |
Publication Date |
2011-09-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-3387;1748-3395; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
38.986 |
Times cited |
129 |
Open Access |
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Notes |
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Approved |
Most recent IF: 38.986; 2011 IF: 27.270 |
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Call Number |
UA @ lucian @ c:irua:93296 |
Serial |
3813 |
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Author |
Jiang, Y.; Mao, J.; Moldovan, D.; Masir, M.R.; Li, G.; Watanabe, K.; Taniguchi, T.; Peeters, F.M.; Andrei, E.Y. |
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Title |
Tuning a circular p-n junction in graphene from quantum confinement to optical guiding |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
12 |
Issue |
11 |
Pages |
1045-+ |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
<script type='text/javascript'>document.write(unpmarked('The photon-like propagation of the Dirac electrons in graphene, together with its record-high electronic mobility(1-3), can lead to applications based on ultrafast electronic response and low dissipation(4-6). However, the chiral nature of the charge carriers that is responsible for the high mobility also makes it difficult to control their motion and prevents electronic switching. Here, we show how to manipulate the charge carriers by using a circular p-n junction whose size can be continuously tuned from the nanometre to the micrometre scale(7,8). The junction size is controlled with a dual-gate device consisting of a planar back gate and a point-like top gate made by decorating a scanning tunnelling microscope tip with a gold nanowire. The nanometre-scale junction is defined by a deep potential well created by the tip-induced charge. It traps the Dirac electrons in quantum-confined states, which are the graphene equivalent of the atomic collapse states (ACSs) predicted to occur at supercritically charged nuclei(9-13). As the junction size increases, the transition to the optical regime is signalled by the emergence of whispering-gallery modes(14-16), similar to those observed at the perimeter of acoustic or optical resonators, and by the appearance of a Fabry-Perot interference pattern(17-20) for junctions close to a boundary.')); |
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Corporate Author |
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Thesis |
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Publisher |
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Wos |
000414531800011 |
Publication Date |
2017-09-15 |
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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 |
1748-3387; 1748-3395 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
38.986 |
Times cited |
65 |
Open Access |
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Notes |
; The authors acknowledge funding provided by DOE-FG02-99ER45742 (STM/STS) and NSF DMR 1708158 (fabrication). Theoretical work was supported by ESF-EUROCORES-EuroGRAPHENE, FWO VI and the Methusalem program of the Flemish government. ; |
Approved |
Most recent IF: 38.986 |
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Call Number |
UA @ lucian @ c:irua:147406 |
Serial |
4902 |
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Author |
Hu, S.; Gopinadhan, K.; Rakowski, A.; Neek-Amal, M.; Heine, T.; Grigorieva, I.V.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
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Title |
Transport of hydrogen isotopes through interlayer spacing in van der Waals crystals |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
13 |
Issue |
6 |
Pages |
468-+ |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Atoms start behaving as waves rather than classical particles if confined in spaces commensurate with their de Broglie wavelength. At room temperature this length is only about one angstrom even for the lightest atom, hydrogen. This restricts quantum-confinement phenomena for atomic species to the realm of very low temperatures(1-5). Here, we show that van der Waals gaps between atomic planes of layered crystals provide angstrom-size channels that make quantum confinement of protons apparent even at room temperature. Our transport measurements show that thermal protons experience a notably higher barrier than deuterons when entering van der Waals gaps in hexagonal boron nitride and molybdenum disulfide. This is attributed to the difference in the de Broglie wavelengths of the isotopes. Once inside the crystals, transport of both isotopes can be described by classical diffusion, albeit with unexpectedly fast rates comparable to that of protons in water. The demonstrated angstrom-size channels can be exploited for further studies of atomistic quantum confinement and, if the technology can be scaled up, for sieving hydrogen isotopes. |
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Corporate Author |
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Wos |
000434715700015 |
Publication Date |
2018-04-04 |
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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 |
1748-3387; 1748-3395 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
38.986 |
Times cited |
32 |
Open Access |
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Notes |
; The authors acknowledge support from the Lloyd's Register Foundation, EPSRC – EP/N010345/1, the European Research Council ARTIMATTER project – ERC-2012-ADG and from Graphene Flagship. M.L.-H. acknowledges a Leverhulme Early Career Fellowship. ; |
Approved |
Most recent IF: 38.986 |
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Call Number |
UA @ lucian @ c:irua:152014UA @ admin @ c:irua:152014 |
Serial |
5046 |
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Author |
Mogg, L.; Hao, G.-P.; Zhang, S.; Bacaksiz, C.; Zou, Y.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
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Title |
Atomically thin micas as proton-conducting membranes |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
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Volume |
14 |
Issue |
10 |
Pages |
962-+ |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Monolayers of graphene and hexagonal boron nitride (hBN) are highly permeable to thermal protons1,2. For thicker two-dimensional (2D) materials, proton conductivity diminishes exponentially, so that, for example, monolayer MoS2 that is just three atoms thick is completely impermeable to protons1. This seemed to suggest that only one-atom-thick crystals could be used as proton-conducting membranes. Here, we show that few-layer micas that are rather thick on the atomic scale become excellent proton conductors if native cations are ion-exchanged for protons. Their areal conductivity exceeds that of graphene and hBN by one to two orders of magnitude. Importantly, ion-exchanged 2D micas exhibit this high conductivity inside the infamous gap for proton-conducting materials3, which extends from ∼100 °C to 500 °C. Areal conductivity of proton-exchanged monolayer micas can reach above 100 S cm−2 at 500 °C, well above the current requirements for the industry roadmap4. We attribute the fast proton permeation to ~5-Å-wide tubular channels that perforate micas’ crystal structure, which, after ion exchange, contain only hydroxyl groups inside. Our work indicates that there could be other 2D crystals5 with similar nanometre-scale channels, which could help close the materials gap in proton-conducting applications. |
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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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Wos |
000488977100016 |
Publication Date |
2019-09-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-3387; 1748-3395 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
38.986 |
Times cited |
37 |
Open Access |
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Notes |
; The work was supported by the Lloyd's Register Foundation, the Engineering and Physical Sciences Research Council (EPSRC)-EP/N010345/1, EP/M010619/1 and EP/ P009050/1, the European Research Council, the Graphene Flagship and the Royal Society. M.L.-H. acknowledges a Leverhulme Early Career Fellowship, G.-P.H. acknowledges a Marie Curie International Incoming Fellowship, and L.M. acknowledges the EPSRC NOWNano programme for funding. Y.Z. acknowledges the assistance of Eric Prestat in TEM specimen preparation. Computational resources were provided by the TUBITAK ULAKBIM High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; |
Approved |
Most recent IF: 38.986 |
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Call Number |
UA @ admin @ c:irua:163589 |
Serial |
5407 |
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Author |
Fitawok, M.B.; Derudder, B.; Minale, A.S.; Van Passel, S.; Adgo, E.; Nyssen, J. |
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Title |
Stakeholder perspectives on farmers' resistance towards urban land-use changes in Bahir Dar, Ethiopia |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Journal of land use science |
Abbreviated Journal |
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Volume |
18 |
Issue |
1 |
Pages |
25-38 |
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Keywords |
A1 Journal article; Engineering Management (ENM) |
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Abstract |
Owing to growing uncontrolled land-use change and urban expansion, farmers in urban fringes are struggling to sustain their livelihood. Farmers have been expressing their dissatisfaction at different times. This study analyzes the stakeholders' perspectives on the causes and outcomes of farmers' resistance to land-use change and urban expansion processes by zooming in on Bahir Dar, Ethiopia. The paper is based on focus group discussions with farmers in the neighboring villages, local agricultural extension experts, and, subsequently, key informant interviews of local government officials. Juxtaposing farmers' and local experts' positions reveals that inadequate compensations during land expropriation, lack of good governance in the urban expansion process, and inaccessibility of infrastructures are primary reasons for the farmers' struggle against urban expansion in the urban fringes. This study provides insights into the consequences of unplanned urban development challenges and may inform research and policymaking on sustainable urban development in the area and beyond. |
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Corporate Author |
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Place of Publication |
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Wos |
000936397600001 |
Publication Date |
2023-02-22 |
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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 |
1747-423x; 1747-4248 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.2 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.2; 2023 IF: NA |
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Call Number |
UA @ admin @ c:irua:195109 |
Serial |
7368 |
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Author |
Torfs, E.; Vajs, J.; Bidart de Macedo, M.; Cools, F.; Vanhoutte, B.; Gorbanev, Y.; Bogaerts, A.; Verschaeve, L.; Caljon, G.; Maes, L.; Delputte, P.; Cos, P.; Komrlj, J.; Cappoen, D. |
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Title |
Synthesis and in vitro investigation of halogenated 1,3-bis(4-nitrophenyl)triazenide salts as antitubercular compounds |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Chemical biology and drug design |
Abbreviated Journal |
Chem Biol Drug Des |
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Volume |
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Issue |
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Pages |
1-10 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The diverse pharmacological properties of the diaryltriazenes have sparked the interest to investigate their potential to be repurposed as antitubercular drug candidates. In an attempt to improve the antitubercular activity of a previously constructed diaryltriazene library, eight new halogenated nitroaromatic triazenides were synthesized and underwent biological evaluation. The potency of the series was confirmed against the Mycobacterium tuberculosis lab strain H37Ra, and for the most potent derivative, we observed a minimal inhibitory concentration of 0.85 μm. The potency of the triazenide derivatives against M. tuberculosis H37Ra was found to be highly dependent on the nature of the halogenated phenyl substituent and less dependent on cationic species used for the preparation of the salts. Although the inhibitory concentration against J774A.1 macrophages was observed at 3.08 μm, the cellular toxicity was not mediated by the generation of nitroxide intermediate as confirmed by electron paramagnetic resonance spectroscopy, whereas no in vitro mutagenicity could be observed for the new halogenated nitroaromatic triazenides when a trifluoromethyl substituent was present on both the aryl moieties. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Copenhagen |
Editor |
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Language |
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Wos |
000422952300027 |
Publication Date |
2017-08-28 |
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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 |
1747-0277; 1747-0285; 1397-002x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.396 |
Times cited |
5 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 2.396 |
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Call Number |
UA @ lucian @ c:irua:147182 |
Serial |
4794 |
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| Permanent link to this record |
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Author |
Béché, A.; Van Boxem, R.; Van Tendeloo, G.; Verbeeck, J. |
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Title |
Magnetic monopole field exposed by electrons |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
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Volume |
10 |
Issue |
1 |
Pages |
26-29 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The experimental search for magnetic monopole particles(1-3) has, so far, been in vain. Nevertheless, these elusive particles of magnetic charge have fuelled a rich field of theoretical study(4-10). Here, we created an approximation of a magnetic monopole in free space at the end of a long, nanoscopically thin magnetic needle(11). We experimentally demonstrate that the interaction of this approximate magnetic monopole field with a beam of electrons produces an electron vortex state, as theoretically predicted for a true magnetic monopole(3,11-18). This fundamental quantum mechanical scattering experiment is independent of the speed of the electrons and has consequences for all situations where electrons meet such monopole magnetic fields, as, for example, in solids. The set-up not only shows an attractive way to produce electron vortex states but also provides a unique insight into monopole fields and shows that electron vortices might well occur in unexplored solid-state physics situations. |
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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 |
000328940100012 |
Publication Date |
2013-11-29 |
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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 |
1745-2473;1745-2481; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
22.806 |
Times cited |
131 |
Open Access |
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Notes |
Vortex; Countatoms; Fwo ECASJO_; |
Approved |
Most recent IF: 22.806; 2014 IF: 20.147 |
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Call Number |
UA @ lucian @ c:irua:113740UA @ admin @ c:irua:113740 |
Serial |
1885 |
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Author |
Lukyanchuk, I.; Vinokur, V.M.; Rydh, A.; Xie, R.; Milošević, M.V.; Welp, U.; Zach, M.; Xiao, Z.L.; Crabtree, G.W.; Bending, S.J.; Peeters, F.M.; Kwok, W.K. |
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Title |
Rayleigh instability of confined vortex droplets in critical superconductors |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
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Volume |
11 |
Issue |
11 |
Pages |
21-25 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Depending on the Ginzburg-Landau parameter kappa, superconductors can either be fully diamagnetic if kappa < 1/root 2 (type I superconductors) or allow magnetic flux to penetrate through Abrikosov vortices if kappa > 1/root 2 (type II superconductors; refs 1,2). At the Bogomolny critical point, kappa = kappa(c) = 1/root 2, a state that is infinitely degenerate with respect to vortex spatial configurations arises(3,4). Despite in-depth investigations of conventional type I and type II superconductors, a thorough understanding of the magnetic behaviour in the near-Bogomolny critical regime at kappa similar to kappa(c) remains lacking. Here we report that in confined systems the critical regime expands over a finite interval of kappa forming a critical superconducting state. We show that in this state, in a sample with dimensions comparable to the vortex core size, vortices merge into a multi-quanta droplet, which undergoes Rayleigh instability(5) on increasing kappa and decays by emitting single vortices. Superconducting vortices realize Nielsen-Olesen singular solutions of the Abelian Higgs model, which is pervasive in phenomena ranging from quantum electrodynamics to cosmology(6-9). Our study of the transient dynamics of Abrikosov-Nielsen-Olesen vortices in systems with boundaries promises access to non-trivial effects in quantum field theory by means of bench-top laboratory experiments. |
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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 |
000346831100018 |
Publication Date |
2014-11-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
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| |
ISSN |
1745-2473;1745-2481; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
22.806 |
Times cited |
20 |
Open Access |
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| |
Notes |
; We would like to thank N. Nekrasov for illuminating discussions. The work was supported by the US Department of Energy, Office of Science Materials Sciences and Engineering Division (V.M.V., W.K.K., U.W., R.X., M.Z., Z.L.X., G.W.C. and partially I.L. through the Materials Theory Institute), by FP7-IRSES-SIMTECH and ITN-NOTEDEV programs (I.L.), and by the Flemish Science Foundation (FWO-Vlaanderen) (M.V.M. and F.M.P.). ; |
Approved |
Most recent IF: 22.806; 2015 IF: 20.147 |
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| |
Call Number |
c:irua:122791 c:irua:122791 |
Serial |
2815 |
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| Permanent link to this record |
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Author |
Roditchev, D.; Brun, C.; Serrier-Garcia, L.; Cuevas, J.C.; Bessa, V.H.L.; Milošević, M.V.; Debontridder, F.; Stolyarov, V.; Cren, T. |
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Title |
Direct observation of Josephson vortex cores |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
|
| |
Volume |
11 |
Issue |
11 |
Pages |
332-337 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Superconducting correlations may propagate between two superconductors separated by a tiny insulating or metallic barrier, allowing a dissipationless electric current to flow(1,2). In the presence of a magnetic field, the maximum supercurrent oscillates(3) and each oscillation corresponding to the entry of one Josephson vortex into the barrier(4). Josephson vortices are conceptual blocks of advanced quantum devices such as coherent terahertz generators(5) or qubits for quantum computing(6), in which on-demand generation and control is crucial. Here, we map superconducting correlations inside proximity Josephson junctions(7) using scanning tunnelling microscopy. Unexpectedly, we find that such Josephson vortices have real cores, in which the proximity gap is locally suppressed and the normal state recovered. By following the Josephson vortex formation and evolution we demonstrate that they originate from quantum interference of Andreev quasiparticles(8), and that the phase portraits of the two superconducting quantum condensates at edges of the junction decide their generation, shape, spatial extent and arrangement. Our observation opens a pathway towards the generation and control of Josephson vortices by applying supercurrents through the superconducting leads of the junctions, that is, by purely electrical means without any need for a magnetic field, which is a crucial step towards high-density on-chip integration of superconducting quantum devices. |
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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 |
000352163100016 |
Publication Date |
2015-02-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1745-2473;1745-2481; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
22.806 |
Times cited |
102 |
Open Access |
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Notes |
T.C., C.B., F.D., V.S. and D.R. acknowledge financial support from the French ANR project and the French-Russian program PICS-CNRS/RAS. The authors also thank V. Cherkez for assistance during experiments and V. Vinokur (Argonne National Laboratory, Illinois USA) and A. Buzdin (University of Bordeaux 1, France) for stimulating discussions. J.C.C. acknowledges financial support from the Spanish MICINN (Contract No. FIS2011-28851-C1). V.H.L.B. acknowledges support from CNPq Brazil and productive discussions with Prof. A. Chaves (UFC, Brazil). M.V.M. acknowledges support from Research Foundation Flanders (FWO-Vlaanderen) and CAPES Brazil (PVE project BEX1392/11-5). |
Approved |
Most recent IF: 22.806; 2015 IF: 20.147 |
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| |
Call Number |
c:irua:132524 c:irua:132524 |
Serial |
3943 |
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| Permanent link to this record |
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Author |
Partoens, B. |
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Title |
Spinorbit interactions : hide and seek |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
|
| |
Volume |
10 |
Issue |
|
Pages |
333-334 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
It is commonly believed that solids with spatial inversion symmetry do not display spinorbit effects. However, first-principles calculations now reveal unexpected spin structure for centrosymmetric crystals |
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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 |
000335371200003 |
Publication Date |
2014-04-11 |
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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 |
|
Edition |
|
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| |
ISSN |
1745-2473; 1745-2481 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
22.806 |
Times cited |
8 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 22.806; 2014 IF: 20.147 |
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Call Number |
UA @ lucian @ c:irua:141068 |
Serial |
4608 |
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| Permanent link to this record |
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Author |
Wang, D.; Dasgupta, T.; van der Wee, E.B.; Zanaga, D.; Altantzis, T.; Wu, Y.; Coli, G.M.; Murray, C.B.; Bals, S.; Dijkstra, M.; van Blaaderen, A. |
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Title |
Binary icosahedral clusters of hard spheres in spherical confinement |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat Phys |
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| |
Volume |
|
Issue |
|
Pages |
1-9 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
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Abstract |
The influence of geometry on the local and global packing of particles is important to many fundamental and applied research themes, such as the structure and stability of liquids, crystals and glasses. Here we show by experiments and simulations that a binary mixture of hard-sphere-like nanoparticles crystallizing into a MgZn(2)Laves phase in bulk spontaneously forms icosahedral clusters in slowly drying droplets. Using advanced electron tomography, we are able to obtain the real-space coordinates of all the spheres in the icosahedral clusters of up to about 10,000 particles. The local structure of 70-80% of the particles became similar to that of the MgCu(2)Laves phase. These observations are important for photonic applications. In addition, we observed in simulations that the icosahedral clusters nucleated away from the spherical boundary, which is distinctly different from that of the single species clusters. Our findings open the way for particle-level studies of nucleation and growth of icosahedral clusters, and of binary crystallization. The authors investigate out-of-equilibrium crystallization of a binary mixture of sphere-like nanoparticles in small droplets. They observe the spontaneous formation of an icosahedral structure with stable MgCu(2)phases, which are promising for photonic applications. |
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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 |
000564497300002 |
Publication Date |
2020-08-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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| |
ISSN |
1745-2473; 1745-2481 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
19.6 |
Times cited |
38 |
Open Access |
OpenAccess |
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Notes |
; D.W., E.B.v.d.W. and A.v.B. acknowledge partial financial support from the European Research Council under the European Union's Seventh Framework Programme (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. T.D. and M. D. acknowledge financial support from the Industrial Partnership Programme, 'Computational Sciences for Energy Research' (grant number 13CSER025), of the Netherlands Organization for Scientific Research (NWO), which was co-financed by Shell Global Solutions International BV G.M.C. was also financially supported by NWO. S.B. acknowledges financial support from ERC Consolidator Grant Number 815128 REALNANO. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). C.B.M. and Y.W. acknowledge support for materials synthesis from the Office of Naval Research Multidisciplinary University Research Initiative Award ONR N00014-18-1-2497. G. A. Blab is gratefully acknowledged for 3D printing numerous truncated tetrahedra, which increased our understanding of the connection between the binary icosahedral cluster and Laves phase structures. N. Tasios is sincerely thanked for providing the code for the diffraction pattern calculation. M. Hermes is sincerely thanked for providing interactive views of the structures in this work. We thank G. van Tendeloo, M. Engel, J. Wang, S. Dussi, L. Filion, E. Boattini, S. Paliwal, N. Tasios, B. van der Meer, I. Lobato, J. Wu and L. Laurens for fruitful discussions. We acknowledge the EM Square centre at Utrecht University for the access to the microscopes. ; sygma |
Approved |
Most recent IF: 19.6; 2020 IF: 22.806 |
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Call Number |
UA @ admin @ c:irua:172044 |
Serial |
6460 |
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| Permanent link to this record |
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Author |
Mao, J.; Jiang, Y.; Moldovan, D.; Li, G.; Watanabe, K.; Taniguchi, T.; Masir, M.R.; Peeters, F.M.; Andrei, E.Y. |
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Title |
Realization of a tunable artificial atom at a supercritically charged vacancy in graphene |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
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| |
Volume |
12 |
Issue |
12 |
Pages |
545-549 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Graphene’s remarkable electronic properties have fuelled the vision of a graphene-based platform for lighter, faster and smarter electronics and computing applications. One of the challenges is to devise ways to tailor graphene’s electronic properties and to control its charge carriers. Here we show that a single-atom vacancy in graphene can stably host a local charge and that this charge can be gradually built up by applying voltage pulses with the tip of a scanning tunnelling microscope. The response of the conduction electrons in graphene to the local charge is monitored with scanning tunnelling and Landau level spectroscopy, and compared to numerical simulations. As the charge is increased, its interaction with the conduction electrons undergoes a transition into a supercritical regime where itinerant electrons are trapped in a sequence of quasi-bound states which resemble an artificial atom. The quasi-bound electron states are detected by a strong enhancement of the density of states within a disc centred on the vacancy site which is surrounded by halo of hole states. We further show that the quasi-bound states at the vacancy site are gate tunable and that the trapping mechanism can be turned on and off, providing a mechanism to control and guide electrons in graphene. |
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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 |
000377475700011 |
Publication Date |
2016-02-22 |
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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 |
1745-2473 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
22.806 |
Times cited |
93 |
Open Access |
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Notes |
; Funding was provided by DOE-FG02-99ER45742 (STM/STS), NSF DMR 1207108 (fabrication and characterization). Theoretical work supported by ESF-EUROCORES-EuroGRAPHENE, FWO-VI and Methusalem programme of the Flemish government. We thank V. F. Libisch, M. Pereira and E. Rossi for useful discussions. ; |
Approved |
Most recent IF: 22.806 |
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| |
Call Number |
c:irua:134210 |
Serial |
4011 |
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| Permanent link to this record |
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Author |
Yang, W.; Misko, V.R.; Nelissen, K.; Kong, M.; Peeters, F.M. |
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Title |
Using self-driven microswimmers for particle separation |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Soft matter |
Abbreviated Journal |
Soft Matter |
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| |
Volume |
8 |
Issue |
19 |
Pages |
5175-5179 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Microscopic self-propelled swimmers capable of autonomous navigation through complex environments provide appealing opportunities for localization, pick-up and delivery of micro and nanoscopic objects. Inspired by motile cells and bacteria, man-made microswimmers have been fabricated, and their motion in patterned surroundings has been experimentally studied. We propose to use self-driven artificial microswimmers for the separation of binary mixtures of colloids. We revealed different regimes of separation, including one with a velocity inversion. Our findings could be of use for various biological and medical applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000303208700009 |
Publication Date |
2012-03-26 |
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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 |
1744-683X;1744-6848; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.889 |
Times cited |
45 |
Open Access |
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Notes |
; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-V1) (Belgium), the National Natural Science Foundation of China (No. 11047111), the State Key Program of National Natural Science of China (No. 51135007), the Research Fund for the Doctoral Program of Higher Education of China (No. 20111415120002), and the Major State Basic Research Development Program of China (973) (No. 2009CB724201). ; |
Approved |
Most recent IF: 3.889; 2012 IF: 3.909 |
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Call Number |
UA @ lucian @ c:irua:98326 |
Serial |
3826 |
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| Permanent link to this record |
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Author |
Liu, Y.; Claes, N.; Trepka, B.; Bals, S.; Lang, P.R. |
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Title |
A combined 3D and 2D light scattering study on aqueous colloidal model systems with tunable interactions |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Soft matter |
Abbreviated Journal |
Soft Matter |
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Volume |
12 |
Issue |
12 |
Pages |
8485-8494 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In this article we report on the synthesis and characterization of a system of colloidal spheres suspended in an aqueous solvent which can be refractive index-matched, thus allowing for investigations of the particle near-wall dynamics by evanescent wave dynamic light scattering at concentrations up to the isotropic to ordered transition and beyond. The particles are synthesized by copolymerization of a fluorinated acrylic ester monomer with a polyethylene-glycol (PEG) oligomer by surfactant free emulsion polymerization. Static and dynamic light scattering experiments in combination with cryo transmission electron microscopy reveal that the particles have a core shell structure with a significant enrichment of the PEG chains on the particles surface. In index-matching DMSO/water suspensions the particles arrange in an ordered phase at volume fraction above 7%, if no additional electrolyte is present. The near-wall dynamics at low volume fraction are quantitatively described by the combination of electrostatic repulsion and hydrodynamic interaction between the particles and the wall. At volume fractions close to the isotropic to ordered transition, the near-wall dynamics are more complex and qualitatively reminiscent of the behaviour which was observed in hard sphere suspensions at high concentrations. |
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Address |
Forschugszentrum Julich, Institute of Complex Systems ICS-3, Julich, Germany. p.lang@fz-juelich.de and Heinrich-Heine Universitat, Dusseldorf, Germany |
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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 |
English |
Wos |
000386247100004 |
Publication Date |
2016-08-22 |
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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 |
1744-683X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.889 |
Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
The authors thank Prof. J. K. G. Dhont and the ICS-3 group for useful discussions and support. YL would like to thank the Marie Sklodowska Curie Initial Training Network SOMATAI under the EU Grant Agreement No. 316866 for financial support. BT contributed to this work during an internship at Forschungszentrum Ju¨lich supported by the International Helmholtz Research School of Biophysics and Soft Matter (IHRS BioSoft), which is gratefully acknowledged. SB and NC acknowledge financial support from the European Research Council (ERC Starting Grant No. 335078-COLOURATOMS).; ECAS_Sara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); |
Approved |
Most recent IF: 3.889 |
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Call Number |
EMAT @ emat @ c:irua:136166 |
Serial |
4292 |
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| Permanent link to this record |
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Author |
Esquivel, M.R.; Zelaya, E. |
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Title |
Synthesis and characterisation of lanthanide-based dioxide |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Advances in applied ceramics |
Abbreviated Journal |
Adv Appl Ceram |
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| |
Volume |
110 |
Issue |
4 |
Pages |
219-224 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
In the present work, the microstructure and structure of La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)(OH)(3) and La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)O(2) is obtained from transmission electron microscopy and X-ray diffraction measurements. Space group P6(3)/m is assigned to the structure of La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)(OH)(3). Lanthanides are assigned to Wyckoff positions 2c. Cell parameters are a=6.375(5) angstrom and c=3.753(5) angstrom. The thermal decomposition of this compound was studied by differential scanning calorimetry. The process is exothermal with an enthalpy change Delta H degrees value of -254 +/- 10 kJ mol(-1). The decomposition kinetics is complex and two global processes with E(a) values of 98 +/- 4 and 61 +/- 2 kJ mol 21 were observed. The product is a lanthanide dioxide. Space group Fm3m is assigned to the La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)O(2). Lanthanides are distributed in Wyckoff positions 4a. The cell parameter is a=5.479(5) angstrom. Nanopores in the oxide surface are obtained using this method and characterised by STEM measurements. |
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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 |
Leeds |
Editor |
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Language |
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Wos |
000291206700006 |
Publication Date |
2011-05-30 |
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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 |
1743-6753;1743-6761; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.325 |
Times cited |
3 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 1.325; 2011 IF: 0.871 |
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Call Number |
UA @ lucian @ c:irua:105588 |
Serial |
3410 |
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Author |
Zhang, F.; Vanmeensel, K.; Batuk, M.; Hadermann, J.; Inokoshi, M.; Van Meerbeek, B.; Naert, I.; Vleugels, J. |
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Title |
Highly-translucent, strong and aging-resistant 3Y-TZP ceramics for dental restoration by grain boundary segregation |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Acta biomaterialia |
Abbreviated Journal |
Acta Biomater |
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Volume |
16 |
Issue |
16 |
Pages |
215-222 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Latest trends in dental restorative ceramics involve the development of full-contour 3Y-TZP ceramics which can avoid chipping of veneering porcelains. Among the challenges are the low translucency and the hydrothermal stability of 3Y-TZP ceramics. In this work, different trivalent oxides (Al2O3, Sc2O3, Nd2O3 and La2O3) were selected to dope 3Y-TZP ceramics. Results show that dopant segregation was a key factor to design hydrothermally stable and high-translucent 3Y-TZP ceramics and the cation dopant radius could be used as a controlling parameter. A large trivalent dopant, oversized as compared to Zr4+, exhibiting strong segregation at the ZrO2 grain boundary was preferred. The introduction of 0.2 mol% La2O3 in conventional 0.10.25 wt.% Al2O3-doped 3Y-TZP resulted in an excellent combination of high translucency and superior hydrothermal stability, while retaining excellent mechanical properties. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
S.l. |
Editor |
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Language |
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Wos |
000351978600021 |
Publication Date |
2015-02-04 |
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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 |
1742-7061; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
6.319 |
Times cited |
54 |
Open Access |
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| |
Notes |
Fwo G043110n |
Approved |
Most recent IF: 6.319; 2015 IF: 6.025 |
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Call Number |
c:irua:124421 |
Serial |
1473 |
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| Permanent link to this record |
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Author |
Tian, H.; Schryvers, D.; Liu, D.; Jiang, Q.; van Humbeeck, J. |
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Title |
Stability of Ni in nitinol oxide surfaces |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Acta biomaterialia |
Abbreviated Journal |
Acta Biomater |
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| |
Volume |
7 |
Issue |
2 |
Pages |
892-899 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The stability of Ni in titanium oxide surface layers on nitinol wires known to release certain amounts of Ni was investigated by first principles density functional theory and transmission electron microscopy. The oxides were identified as a combination of TiO and TiO2 depending on the thickness of the layer. The calculations indicate that free Ni atoms can exist in TiO at ambient temperature while Ni particles form in TiO2, which was confirmed by the transmission electron microscopy observations. The results are discussed with respect to surface stability and Ni release due to free Ni atoms and Ni particles. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
|
|
| |
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
|
| |
Language |
|
Wos |
000286707700047 |
Publication Date |
2010-09-17 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-7061; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.319 |
Times cited |
39 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 6.319; 2011 IF: 4.865 |
|
| |
Call Number |
UA @ lucian @ c:irua:85998 |
Serial |
3128 |
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| Permanent link to this record |
| |
|
| |
|
Author |
Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A. |
|
| |
Title |
Ab initio based atomic scattering amplitudes and {002} electron structure factors of InxGa1-xAs/GaAs quantum wells |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
209 |
Issue |
1 |
Pages |
012040,1-012040,6 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The atomic scattering amplitudes of the various atoms of the systems Ga1−xInxAs, GaAs1−xNx and InAs1−xNx are calculated using the density functional theory (DFT) approach. The scattering amplitudes of N, Ga, As and In in the model systems are compared with the frequently used Doyle and Turner values. Deviation from the latter values is found for small scattering vectors (s<0.3Å−1) and for these scattering vectors dependence on the orientation of the scattering vector and the chemical environment is reported. We suggest a parametrization of these modified scattering amplitudes (MASAs) for small scattering vectors (s<1.0Å−1). The MASAs are exploited within zero pressure classical Metropolis Monte Carlo (MC), finite temperature calculations to investigate the effect of quantum well size on the electron {002} structure factor (SF) of Ga1−xInxAs quantum wells. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000283739100040 |
Publication Date |
2010-02-27 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:85760 |
Serial |
28 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Doria, M.M.; de Romaguera, A.R.C.; Milošević, M.V.; Peeters, F.M. |
|
| |
Title |
Domain coexistence of magnetism and superconductivity : appearance of confined vortex loops |
Type |
P1 Proceeding |
| |
Year |
2008 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
97 |
Issue |
|
Pages |
012070-012070,4 |
|
| |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
|
| |
Abstract |
A magnetic moment inside an extreme type II superconductor can have three, but not one or two, confined vortex loops near to the core. For a sub-micron superconducting particle the confined vortex loops eventually break up and reach the surface turning into external vortex pairs. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000276054100070 |
Publication Date |
2008-03-20 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:99232 |
Serial |
747 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Escoffier, W.; Grigorieva, I.V.; Misko, V.R.; Baelus, B.J.; Peeters, F.M.; Vinnikov, L.Y.; Dubnos, S. |
|
| |
Title |
Formation of vortex clusters and giant vortices in mesoscopic superconducting disks with strong disorder |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
97 |
Issue |
|
Pages |
012172,1-012172,6 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Merged, or giant, multi-quanta vortices (GVs) appear in very small superconductors near the superconducting transition due to strong confinement of magnetic flux. Here we present evidence for a new, pinning-related, mechanism for vortex merger. Using Bitter decoration to visualise vortices in small Nb disks, we show that confinement in combination with strong disorder causes individual vortices to merge into clusters/GVs well below Tc and Hc2, in contrast to well-defined shells of individual vortices found in the absence of pinning. |
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| |
Address |
|
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| |
Corporate Author |
|
Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000276054100171 |
Publication Date |
2008-03-20 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:82320 |
Serial |
1266 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Petrović, D.; Martens, T.; van Dijk, J.; Brok, W.J.M.; Bogaerts, A. |
|
| |
Title |
Modeling of a dielectric barrier discharge used as a flowing chemical reactor |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
133 |
Issue |
|
Pages |
012023,1-012023,8 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
Our aim is to develop and optimize a model for a dielectric barrier discharge used as a chemical reactor for gas treatment. In order to determine the optimum operating conditions, we have studied the influence of the gas flow rate, reactor geometry and applied voltage parameters on the discharge characteristics. For this purpose, a two-dimensional time-dependent fluid model has been applied to an atmospheric pressure DBD in helium with nitrogen impurities, in a cylindrical geometry. The numerical model is based on the continuity and flux equations for each type of particles treated, the electron energy equation and the Poisson equation. The gas flow is incorporated in the flux equations as a source term. The set of coupled partial differential equations is solved by the so-called modified strongly implicit method. The background gas flow is numerically treated separately, assuming in the model that there is no influence of the plasma on the flow. Indeed, the gas convection velocity is calculated using the commercial code Fluent and it is used as input into the 2D fluid model. The plasma characteristics have been studied in terms of gas flow rate, applied voltage amplitude and frequency, and geometrical effects. The electric currents as a function of time for a given applied potential have been obtained, as well as the number densities and fluxes of plasma species. |
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| |
Address |
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| |
Corporate Author |
|
Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000265684100023 |
Publication Date |
2008-11-07 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
6 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:71282 |
Serial |
2115 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Nguyen, N.T.T.; Peeters, F.M. |
|
| |
Title |
Phase-diagram for the magnetic states of the Mn-ion subsystem in a magnetic quantum dot |
Type |
P1 Proceeding |
| |
Year |
2010 |
Publication |
Journal of physics : conference series
T2 – Conference on Quantum Dots 2010 (QD2010), APR 26-30, 2010, Nottingham, ENGLAND |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
012032-12034 |
|
| |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The interplay between two types of spin-spin exchange interaction (namely of the electron with the Mn-ions and the Mn-ions with each other) that are governed by the positions of the Mn-ions and the magnetic field is studied in the case of a Mn-ion doped CdTe quantum dot. We investigate the formation of different magnetic phases and the existence of frustrated magnetic states due to the dominant contribution of the Mn-Mn energy. |
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| |
Address |
|
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| |
Corporate Author |
|
Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000294907400032 |
Publication Date |
2010-09-21 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
245 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
; ; |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:113081 |
Serial |
2582 |
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| Permanent link to this record |
| |
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| |
|
Author |
Mao, M.; Bogaerts, A. |
|
| |
Title |
Plasma chemistry modeling for an inductively coupled plasma used for the growth of carbon nanotubes |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
275 |
Issue |
1 |
Pages |
012021,1-012021,9 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
A hybrid model, called the hybrid plasma equipment model (HPEM), is used to describe the plasma chemistry in an inductively coupled plasma, operating in a gas mixture of C2H2 with either H2 or NH3, as typically used for carbon nanotube (CNT) growth. Two-dimensional profiles of power density, electron temperature and density, gas temperature, and densities of some plasma species are plotted and analyzed. Besides, the fluxes of the various plasma species towards the substrate (where the CNTs can be grown), as well as the decomposition rates of the feedstock gases (C2H2, NH3 and H2), are calculated as a function of the C2H2 fraction in both gas mixtures. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
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| |
Language |
|
Wos |
|
Publication Date |
2011-02-09 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:85859 |
Serial |
2631 |
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| Permanent link to this record |
| |
|
| |
|
Author |
Neyts, E.; Bogaerts, A.; van de Sanden, M.C.M. |
|
| |
Title |
Reaction mechanisms and thin a-C:H film growth from low energy hydrocarbon radicals |
Type |
A1 Journal article |
| |
Year |
2007 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
86 |
Issue |
|
Pages |
12020-12020,15 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
Molecular dynamics simulations using the Brenner potential have been performed to investigate reaction mechanisms of various hydrocarbon radicals with low kinetic energies on amorphous hydrogenated carbon (a-C:H) surfaces and to simulate thin a-C:H film growth. Experimental data from an expanding thermal plasma setup were used as input for the simulations. The hydrocarbon reaction mechanisms were studied both during growth of the films and on a set of surface sites specific for a-C:H surfaces. Thin film growth was studied using experimentally detected growth species. It is found that the reaction mechanisms and sticking coefficients are dependent on the specific surface sites, and the structural properties of the growth radicals. Furthermore, it is found that thin a-C:H films can be densified using an additional H-flux towards the substrate. |
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| |
Address |
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| |
Corporate Author |
|
Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000256282900020 |
Publication Date |
2007-11-22 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
22 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:65692 |
Serial |
2817 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Müller, K.; Schowalter, M.; Rosenauer, A.; Jansen, J.; Tsuda, K.; Titantah, J.T.; Lamoen, D. |
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| |
Title |
Refinement of chemically sensitive structure factors using parallel and convergent beam electron nanodiffraction |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
209 |
Issue |
1 |
Pages |
012025-012025,4 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We introduce a new method to measure structure factors from parallel beam electron diffraction (PBED) patterns. Bloch wave refinement routines were developed which can minimise the difference between simulated and experimental Bragg intensities via variation of structure factors, Debye parameters, specimen thickness and -orientation. Due to plane wave illumination, the PBED refinement is highly efficient not only in computational respect, but also concerning the experimental effort since energy filtering is shown to have no significant effect on the refinement results. The PBED method was applied to simulated GaAs diffraction patterns to derive systematic errors and rules for the identification of plausible refinement results. The evaluation of experimental GaAs PBED patterns yields a 200 X-ray structure factor of -6.33±0.14. Additionally, we obtained -6.35±0.13 from two-dimensional convergent beam electron diffraction refinements. Both results confirm density functional theory calculations published by Rosenauer et al. and indicate the inaccuracy of isolated atom scattering data, which is crucial e.g. for the composition evaluation by lattice fringe analysis. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
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| |
Language |
|
Wos |
|
Publication Date |
2010-02-27 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record |
|
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:85761 |
Serial |
2855 |
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| Permanent link to this record |
| |
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| |
|
Author |
Nguyen, N.T.T.; Peeters, F.M. |
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| |
Title |
The breakdown of Kohn's theorem in few-electron parabolic quantum dots doped with a single magnetic impurity Mn2+ |
Type |
P1 Proceeding |
| |
Year |
2010 |
Publication |
Journal of physics : conference series
T2 – Conference on Quantum Dots 2010 (QD2010), APR 26-30, 2010, Nottingham, ENGLAND |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
012031-12034 |
|
| |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The cyclotron resonance (CR) absorption spectrum is calculated for a II-VI parabolic quantum dot (QD) containing few electrons and a single magnetic dopant (Mn(2+)). We find that Kohn's theorem no longer holds for this system and that the CR spectrum depends on the number of electrons inside the QD. The electron-Mn-ion interaction strength can be tuned for example by the magnetic field and by moving the Mn-ion to different positions inside the QD. We demonstrate that due to the presence of the Mn-ion the relative motion of the electrons couple with their center-of-mass motion through the electron-Mn-ion spin-spin exchange term resulting in an electron-electron interaction dependence of the magneto-optical absorption spectrum. At the ferromagnetic-antiferromagnetic transition we observe significant discontinuities in the CR lines. |
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| |
Address |
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Corporate Author |
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Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
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| |
Language |
|
Wos |
000294907400031 |
Publication Date |
2010-09-21 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
245 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
1 |
Open Access |
|
|
| |
Notes |
; ; |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:113080 |
Serial |
3572 |
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| Permanent link to this record |
| |
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| |
|
Author |
Lao, M.; Eisterer, M.; Stadel, O.; Meledin, A.; Van Tendeloo, G. |
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| |
Title |
The effect of Y2O3 and YFeO3 additions on the critical current density of YBCO coated conductors |
Type |
P1 Proceeding |
| |
Year |
2014 |
Publication |
1-4 |
Abbreviated Journal |
|
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The pinning mechanism of MOCVD-grown YBCO coated conductors with Y2O3 precipitates was investigated by angle-resolved transport measurement of Je in a wide range of temperature and magnetic fields. Aside from the Y2O3 nanoprecipitates, a-axis grains and threading dislocation along the c-axis were found in the YBCO layer. The Y2O3 precipitates are less effective pinning centers at lower temperature. The tapes with precipitates show a higher anisotropy with larger J(c) at H parallel to ab than H parallel to c. This behavior was attributed to the preferred alignment of the nanoprecipitates along the ab-plane. |
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| |
Address |
|
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| |
Corporate Author |
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Thesis |
|
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| |
Publisher |
Iop publishing ltd |
Place of Publication |
Bristol |
Editor |
|
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| |
Language |
|
Wos |
000350818300068 |
Publication Date |
2014-05-12 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
507 |
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
1 |
Open Access |
|
|
| |
Notes |
eurotapes |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:125444 |
Serial |
3577 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Magnus, W.; Brosens, F.; Sorée, B. |
|
| |
Title |
Time dependent transport in 1D micro- and nanostructures: solving the Boltzmann and Wigner-Boltzmann equations |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
|
| |
Volume |
193 |
Issue |
1 |
Pages |
012004,1-012004,4 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
|
| |
Abstract |
For many decades the Boltzmann distribution function has been used to calculate the non-equilibrium properties of mobile particles undergoing the combined action of various scattering mechanisms and externally applied force fields. When the latter give rise to the occurrence of inhomogeneous potential profiles across the region through which the particles are moving, the numerical solution of the Boltzmann equation becomes a highly complicated task. In this work we highlight a particular algorithm that can be used to solve the time dependent Boltzmann equation as well as its quantum mechanical extension, the WignerBoltzmann equation. As an illustration, we show the calculated distribution function describing electrons propagating under the action of both a uniform and a pronouncedly non-uniform electric field. |
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| |
Address |
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| |
Corporate Author |
|
Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000277100400004 |
Publication Date |
2009-11-17 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
|
Times cited |
2 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ lucian @ c:irua:82861 |
Serial |
3667 |
|
| Permanent link to this record |
