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Author |
Idrissi, H.; Renard, K.; Schryvers, D.; Jacques, P.J. |
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Title |
On the relationship between the twin internal structure and the work-hardening rate of TWIP steels |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
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| |
Volume |
63 |
Issue |
10 |
Pages |
961-964 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
FeMnC and FeMnSiAl TWIP steels deformed under the same conditions exhibit different work-hardening rates. The present study investigates the microstructure of plastically deformed FeMnC and FeMnSiAl samples, particularly the internal structure of the mechanically generated twins and their topology at the grain scale. Twins in the FeMnC steel are finer and full of sessile dislocations, rendering this material distinctly stronger with an improved work-hardening rate. |
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Corporate Author |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000282461800003 |
Publication Date |
2010-07-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1359-6462; |
ISBN |
|
Additional Links  |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.747 |
Times cited |
145 |
Open Access |
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| |
Notes |
Iap |
Approved |
Most recent IF: 3.747; 2010 IF: 2.820 |
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Call Number |
UA @ lucian @ c:irua:84472 |
Serial |
2452 |
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| Permanent link to this record |
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Author |
Pogosov, W.V.; Misko, V.R.; Peeters, F.M. |
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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 |
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| |
Volume |
82 |
Issue |
5 |
Pages |
054523-054523,6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281294700006 |
Publication Date |
2010-08-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:84470 |
Serial |
1334 |
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Author |
Schattschneider, P.; Ennen, I.; Stoger-Pollach, M.; Verbeeck, J.; Mauchamp, V.; Jaouen, M. |
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Title |
Real space maps of magnetic moments on the atomic scale: theory and feasibility |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
110 |
Issue |
8 |
Pages |
1038-1041 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The recently discovered EMCD technique (energy loss magnetic chiral dichroism) can detect atom specific magnetic moments with nanometer resolution, exploiting the spin selectivity of electronic transitions in energy loss spectroscopy. Yet, direct imaging of magnetic moments on the atomic scale is not possible. In this paper we present an extension of EMCD that can overcome this limit. As a model system we chose bcc Fe. We present image simulations of the L3 white line signal, based on the kinetic equation for the density matrix of the 200 kV probe electron. With actual progress in instrumentation (high brightness sources, aberration corrected lenses) this technique should allow direct imaging of spin moments on the atomic scale. |
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Corporate Author |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000281216600016 |
Publication Date |
2009-12-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
10 |
Open Access |
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| |
Notes |
--- |
Approved |
Most recent IF: 2.843; 2010 IF: 2.063 |
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Call Number |
UA @ lucian @ c:irua:84439UA @ admin @ c:irua:84439 |
Serial |
2830 |
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Author |
Afanasov, I.M.; Van Tendeloo, G.; Mateev, A.T. |
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Title |
Production and structure of exfoliated graphite/coke composites modified by ZrO2 nanoparticles |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
New carbon materials |
Abbreviated Journal |
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Volume |
25 |
Issue |
4 |
Pages |
255-260 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Exfoliated graphite/coke composites modified by ZrO2 nanoparticles were produced using two different techniques and characterized by means of X-ray diffraction, scanning and transmission electron microscopy. In the first, low-density exfoliated graphite/coke blocks were dipped repeatedly and alternately in ZrO(NO3)2 and NH4OH solutions and subsequently heat treated at 1200°C in nitrogen to deposit thin layers of ZrO2 nanoparticles on the free surfaces of the carbon matrix. In the second, a mixture of expandable graphite, phenol-formaldehyde resin powder, and ZrOC2O4-modified fibrous cellulose in a sealed container was submitted to thermal shock at 900 °C followed by heat treatment at 1 200 °C in nitrogen to obtain the modified composites. The ZrO2 nanoparticles formed in the second technique were incorporated into the composites in three length scales: 6-30 nm-isolated nanoparticles and small blobs, 200-1000 nm-lengthy dendrite-like structures, and thin layer adhering to the surface of the 1-40 μm long cellulose carbon fibers. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000281534800003 |
Publication Date |
2010-09-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1872-5805; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
Iap-Vi |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:84438 |
Serial |
2721 |
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Author |
Roet, D.; van Espen, P. |
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Title |
Monte Carlo simulation of X-ray spectra from low energy electrons using optical data |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms |
Abbreviated Journal |
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Volume |
268 |
Issue |
17/18 |
Pages |
2794-2800 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
An approach using optical data to simulate both the bremsstrahlung continuum and characteristic K and L X-ray lines generated by low energy electrons (cfr. electron microscopy) in solids is discussed in this paper. The necessary analytical expressions together with the data to calculate the relevant cross sections for elastic and inelastic interactions at these energies along with variance reduction techniques are given. The results of the Monte Carlo simulation are compared to experimental data measured with a JEOL 6300 electron microscope. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281498900039 |
Publication Date |
2010-07-15 |
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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 |
0168-583x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:84261 |
Serial |
8281 |
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Author |
Xu, W.; Dong, H.M.; Li, L.L.; Yao, J.Q.; Vasilopoulos, P.; Peeters, F.M. |
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Title |
Optoelectronic properties of graphene in the presence of optical phonon scattering |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
82 |
Issue |
12 |
Pages |
125304-125304,9 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study in detail the optoelectronic properties of graphene. Considering the electron interactions with photons and phonons, we employ the mass- and energy-balance equations to self-consistently evaluate the photoinduced carrier densities, the optical conductance, and the transmission coefficient in the presence of a linearly polarized radiation field. We demonstrate that the photoinduced carrier densities increase around the electron-photon-phonon resonant transition. They depend strongly on the radiation intensity and frequency, temperature, and dark carrier density. For short-wavelength radiation (L<3 μm), we obtain the universal optical conductance σ0=e2/(4ℏ). Importantly, there exists an optical-absorption window in the radiation wavelength range 4100 μm, which is induced by different transition energies required for interband and intraband optical absorption. The position and width of this window depend sensitively on the temperature and the carrier density of the system. These theoretical results are in line with recent experimental findings and indicate that graphene exhibits important features not only in the visible regime but also in the midinfrared bandwidth. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281516500009 |
Publication Date |
2010-09-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
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| |
Notes |
; This work was supported by the Chinese Academy of Sciences, National Natural Science Foundation of China, and Department of Science and Technology of Yunnan Province. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:84260 |
Serial |
2496 |
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| Permanent link to this record |
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Author |
Földi, P.; Szaszkó-Bogár, V.; Peeters, F.M. |
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Title |
Spin-orbit interaction controlled properties of two-dimensional superlattices |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
82 |
Issue |
11 |
Pages |
115302-115302,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The band structure of two-dimensional artificial superlattices in the presence of (Rashba-type) spin-orbit interaction (SOI) is presented. The position and shape of the energy bands in these spintronic crystals depend on the geometry as well as the strength of the SOI, which can be tuned by external gate voltages. For finite mesoscopic arrays, we show that their conductance properties and possible applications can be understood from these spin-dependent band diagrams. |
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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 |
000281516300005 |
Publication Date |
2010-09-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
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Notes |
; We thank M. G. Benedict and F. Bartha for useful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP) and the Hungarian Scientific Research Fund (OTKA) under Contracts No. T81364 and No. M045596. P.F. was supported by a J. Bolyai grant of the Hungarian Academy of Sciences. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:84259 |
Serial |
3092 |
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Author |
Gehrke, K.; Moshnyaga, V.; Samwer, K.; Lebedev, O.I.; Verbeeck, J.; Kirilenko, D.; Van Tendeloo, G. |
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Title |
Interface controlled electronic variations in correlated heterostructures |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
82 |
Issue |
11 |
Pages |
113101,1-113101,4 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
An interface modification of (LaCa)MnO3-BaTiO3 superlattices was found to massively influence magnetic and magnetotransport properties. Moreover it determines the crystal structure of the manganite layers, changing it from orthorhombic (Pnma) for the conventional superlattice (cSL), to rhombohedral (R3̅ c) for the modified one (mSL). While the cSL shows extremely nonlinear ac transport, the mSL is an electrically homogeneous material. The observations go beyond an oversimplified picture of dead interface layers and evidence the importance of electronic correlations at perovskite interfaces. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281643200001 |
Publication Date |
2010-09-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
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Notes |
This work was supported by DFG via SFB 602, TPA2. |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:84249UA @ admin @ c:irua:84249 |
Serial |
1691 |
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Author |
Bencs, L.; Ravindra, K.; de Hoog, J.; Spolnik, Z.; Bleux, N.; Berghmans, P.; Deutsch, F.; Roekens, E.; Van Grieken, R. |
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Title |
Appraisal of measurement methods, chemical composition and sources of fine atmospheric particles over six different areas of Northern Belgium |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Environmental pollution |
Abbreviated Journal |
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Volume |
158 |
Issue |
11 |
Pages |
3421-3430 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Daily and seasonal variation in the total elemental, organic carbon (OC) and elemental carbon (EC) content and mass of PM2.5 were studied at industrial, urban, suburban and agricultural/rural areas. Continuous (optical Dustscan, standard tapered element oscillating micro-balance (TEOM), TEOM with filter dynamics measurement system), semi-continuous (Partisol filter-sampling) and non-continuous (Dekati-impactor sampling and gravimetry) methods of PM2.5 mass monitoring were critically evaluated. The average elemental fraction accounted for 26% of the PM2.5 mass measured by gravimetry. Metals, like K, Mn, Fe, Cu, Zn and Pb were strongly inter-correlated, also frequently with non-metallic elements (P, S, Cl and/or Br) and EC/OC. A high OC/EC ratio (29) was generally observed. The total carbon content of PM2.5 ranged between 3 and 77% (averages: 1232%), peaking near industrial/heavy trafficked sites. Principal component analysis identified heavy oil burning, ferrous/non-ferrous industry and vehicular emissions as the main sources of metal pollution. This work compares various aerosol monitoring methods to characterize PM2.5 over six locations of different anthropogenic activities over Northern Belgium. |
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Corporate Author |
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Place of Publication |
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Wos |
000282563200009 |
Publication Date |
2010-08-23 |
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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 |
0269-7491; 1873-6424 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:84237 |
Serial |
7488 |
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Author |
Harlay, J.; Borges, A.V.; van der Zee, C.; Delille, B.; Godoi, R.H.M.; Schiettecatte, L.-S.; Roevros, N.; Aerts, K.; Lapernat, P.-E.; Rebreanu, L.; Groom, S.; Daro, M.-H.; Van Grieken, R.; Chou, L. |
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Title |
Biogeochemical study of a coccolithophore bloom in the northern Bay of Biscay (NE Atlantic Ocean) in June 2004 |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Progress in oceanography |
Abbreviated Journal |
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Volume |
86 |
Issue |
3/4 |
Pages |
317-336 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The present paper synthesizes data obtained during a multidisciplinary cruise carried out in June 2004 at the continental margin of the northern Bay of Biscay. The data-set allows to describe the different stages of a coccolithophore bloom dominated by Emiliania huxleyi. The cruise was carried out after the main spring phytoplankton bloom that started in mid-April and peaked in mid-May. Consequently, low phosphate (PO4 < 0.2 μM) and silicate (DSi < 2.0 μM) concentrations, low partial pressure of carbon dioxide (pCO2) and high calcite saturation degree in surface waters combined with thermal stratification, probably favoured the blooming of coccolithophores. During the period of the year our cruise was carried out, internal tides induce enhanced vertical mixing at the continental shelf break leading to the injection of inorganic nutrients to surface waters that probably trigger the bloom. The bloom developed as the water-column stratified and as the water mass was advected over the continental shelf, following the general residual circulation in the area. The most developed phase of the bloom was sampled in a remote sensed high reflectance (HR) patch over the continental shelf that was characterized by low chlorophyll-a (Chl-a) concentration in surface waters (<1.0 μg L−1), high particulate inorganic carbon (PIC) concentration (not, vert, similar8 μmol L−1) and coccolithophore abundance up to 57 × 106 cells L−1. Transparent exopolymer particles (TEP) concentrations ranged between 15 and 75 μg C L−1 and carbon content of TEP represented up to 26% of the particulate organic carbon (POC; maximum concentration of 15.5 μmol L−1 in the upper 40 m). Integrated primary production (PP) ranged between 210 and 680 mg C m−2 d−1 and integrated calcification (CAL) ranged between 14 and 140 mg C m−2 d−1, within the range of PP and CAL values previously reported during coccolithophore blooms in open and shelf waters of the North Atlantic Ocean. Bacterial protein production (BPP) measurements in surface waters (0.30.7 μg C L−1 h−1) were much higher than those reported during early phases of coccolithophore blooms in natural conditions, but similar to those during peak and declining coocolithophorid blooms reported in mesocosms. Total alkalinity anomalies with respect to conservative mixing (ΔTA) down to −49 μmol kg−1 are consistent with the occurrence of biogenic precipitation of calcite, while pCO2 remained 15107 μatm lower than atmospheric equilibrium (372 μatm). The correlation between ΔTA and pCO2 suggested that pCO2 increased in part due to calcification, but this increase was insufficient to overcome the background under-saturation of CO2. This is related to the biogeochemical history of the water masses due to net carbon fixation by the successive phytoplankton blooms in the area prior to the cruise, hence, the investigated area remained a sink for atmospheric CO2 despite calcification. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281937800001 |
Publication Date |
2010-04-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0079-6611 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:84236 |
Serial |
7560 |
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| Permanent link to this record |
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Author |
Liu, Y.; Cheng, F.; Li, X.J.; Peeters, F.M.; Chang, K. |
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Title |
Tuning of the two electron states in quantum rings through the spin-orbit interaction |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
82 |
Issue |
4 |
Pages |
1-7 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The effect of the Coulomb interaction on the energy spectrum and anisotropic distribution of two electron states in a quantum ring in the presence of Rashba spin-orbit interaction (RSOI) and Dresselhaus SOI (DSOI) is investigated in the presence of a perpendicular magnetic field. We find that the interplay between the RSOI and DSOI makes the single quantum ring behaves like a laterally coupled quantum dot and the interdot coupling can be tuned by changing the strengths of the SOIs. The interplay can lead to singlet-triplet state mixing and anticrossing behavior when the singlet and triplet states meet with increasing magnetic field. The two electron ground state displays a bar-bell-like spatial anisotropic distribution in a quantum ring at a specific crystallographic direction, i.e., [110] or [11̅ 0], which can be switched by reversing the direction of the perpendicular electric field. The ground state exhibits a singlet-triplet state transition with increasing magnetic field and strengths of RSOI and DSOI. An anisotropic electron distribution is predicted which can be detected through the measurement of its optical properties. |
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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 |
000280234100006 |
Publication Date |
2010-07-22 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
|
| |
Notes |
; This work was supported by NSFC under Grants No. 60525405 and No. 10874175 and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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| |
Call Number |
UA @ lucian @ c:irua:84087 |
Serial |
3756 |
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| Permanent link to this record |
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Author |
Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Filonenko, V.P.; Gonnissen, J.; Tan, H.; Verbeeck, J.; Gemmi, M.; Antipov, E.V.; Rosner, H. |
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| |
Title |
Direct space structure solution from precession electron diffraction data: resolving heavy and light scatterers in Pb13Mn9O25 |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
110 |
Issue |
7 |
Pages |
881-890 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The crystal structure of a novel compound Pb13Mn9O25 has been determined through a direct space structure solution with a Monte-Carlo-based global optimization using precession electron diffraction data (a=14.177(3) Å, c=3.9320(7) Å, SG P4/m, RF=0.239) and compositional information obtained from energy dispersive X-ray analysis and electron energy loss spectroscopy. This allowed to obtain a reliable structural model even despite the simultaneous presence of both heavy (Pb) and light (O) scattering elements and to validate the accuracy of the electron diffraction-based structure refinement. This provides an important benchmark for further studies of complex structural problems with electron diffraction techniques. Pb13Mn9O25 has an anion- and cation-deficient perovskite-based structure with the A-positions filled by the Pb atoms and 9/13 of the B positions filled by the Mn atoms in an ordered manner. MnO6 octahedra and MnO5 tetragonal pyramids form a network by sharing common corners. Tunnels are formed in the network due to an ordered arrangement of vacancies at the B-sublattice. These tunnels provide sufficient space for localization of the lone 6s2 electron pairs of the Pb2+ cations, suggested as the driving force for the structural difference between Pb13Mn9O25 and the manganites of alkali-earth elements with similar compositions. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000280050900023 |
Publication Date |
2010-04-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
24 |
Open Access |
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| |
Notes |
Fwo; Bof; Esteem |
Approved |
Most recent IF: 2.843; 2010 IF: 2.063 |
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| |
Call Number |
UA @ lucian @ c:irua:84085UA @ admin @ c:irua:84085 |
Serial |
721 |
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| Permanent link to this record |
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Author |
Maignan, A.; Lebedev, O.I.; Van Tendeloo, G.; Martin, C.; Hebert, S. |
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| |
Title |
Metal to insulator transition in the n-type hollandite vanadate Pb1.6V8O16 |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
82 |
Issue |
3 |
Pages |
035122, 1-035122,5 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The transport and magnetic measurements of polycrystalline Pb1.6V8O16 hollandite reveal a concomitant metal to insulator and antiferromagnetic transition at TMI≈140 K. A clear localization is found below TMI, evidenced by a rapid increase in the absolute value of the negative Seebeck coefficient. The structural study by x-ray and transmission electron microscopy confirms the hollandite structure and shows that no structural transition occurs at TMI, ruling out a possible charge orbital ordering. The negative Seebeck coefficient observed from 50 K up to 900 K, with values reaching S=−38 μV K−1 at 900 K, is explained by the electron doping of ∼1.4e− in the V empty t2g orbitals responsible for the bad metal resistivity (ρ900 K∼2 mΩ cm). As this S value is close to that obtained by considering only the spin and orbital degeneracies, it is expected that |S| for such vanadates will not be sensitive at high temperature to the t2g band filling |
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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 |
000280366300002 |
Publication Date |
2010-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
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 |
10 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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| |
Call Number |
UA @ lucian @ c:irua:84065 |
Serial |
2009 |
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| Permanent link to this record |
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Author |
Fang, C.M.; Sluiter, M.H.F.; van Huis, M.; Ande, C.K.; Zandbergen, H.W. |
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Title |
Origin of predominance of cementite among iron carbides in steel at elevated temperature |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
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| |
Volume |
105 |
Issue |
5 |
Pages |
4 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A long-standing challenge in physics is to understand why cementite is the predominant carbide in steel. Here we show that the prevalent formation of cementite can be explained only by considering its stability at elevated temperature. A systematic highly accurate quantum mechanical study was conducted on the stability of binary iron carbides. The calculations show that all the iron carbides are unstable relative to the elemental solids, -Fe and graphite. Apart from a cubic Fe23C6 phase, the energetically most favorable carbides exhibit hexagonal close-packed Fe sublattices. Finite-temperature analysis showed that contributions from lattice vibration and anomalous Curie-Weis magnetic ordering, rather than from the conventional lattice mismatch with the matrix, are the origin of the predominance of cementite during steel fabrication processes. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000280472900008 |
Publication Date |
2010-07-30 |
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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 |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.462 |
Times cited |
65 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 8.462; 2010 IF: 7.622 |
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| |
Call Number |
UA @ lucian @ c:irua:84064 |
Serial |
2526 |
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| Permanent link to this record |
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Author |
Terzano, R.; Santoro, A.; Spagnuolo, M.; Vekemans, B.; Medici, L.; Janssens, K.; Göttlicher, J.; Denecke, M.A.; Mangold, S.; Ruggiero, P. |
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Title |
Solving mercury (Hg) speciation in soil samples by synchrotron X-ray microspectroscopic techniques |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Environmental pollution |
Abbreviated Journal |
Environ Pollut |
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| |
Volume |
158 |
Issue |
8 |
Pages |
2702-2709 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg1. Hg chemical forms were identified and quantified by sequential extractions and bulkand micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as m-XRF, m-XRD and m-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 mm. The main Hg-species found in the soil samples were metacinnabar (b-HgS), cinnabar (a-HgS), corderoite (Hg3S2Cl2), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 mm. No interaction among Hg-species and soil components was observed. All the observed Hgspecies originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution. |
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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 |
000280571500026 |
Publication Date |
2010-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0269-7491 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
5.099 |
Times cited |
30 |
Open Access |
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| |
Notes |
; This research was partially financed by the MIUR (COFIN 2005) project “Innovative chemical, physical, and biological methods to characterize and remediate soils polluted by heavy metals (MICROS)”. Synchrotron experiments at HASYLAB were financially supported by the European Community-Research Infrastructure Action under the FP6 “Structuring the European Research Area” Program I(Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). This research was also performed as part of the “Interuniversity Attraction Poles” (IAP6) Program financed by the Belgian government. We thank Gerald Falkenberg and Karen Rickers-Appel for their scientific and technical support in obtaining the experimental data at Beam line L (HASYLAB, DESY, Hamburg, Germany). ; |
Approved |
Most recent IF: 5.099; 2010 IF: 3.395 |
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Call Number |
UA @ admin @ c:irua:84050 |
Serial |
5835 |
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Author |
Bezjak, J.; Abakumov, A.M.; Recnik, A.; Krzmanc, M.M.; Jancar, B.; Suvorov, D. |
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Title |
The local structure and composition of Ba4Nb2O9-based oxycarbonates |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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| |
Volume |
183 |
Issue |
8 |
Pages |
1823-1828 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
X-ray powder-diffraction(XRD),high-resolutiontransmissionelectronmicroscopy(HRTEM),electron diffraction(ED),infraredspectroscopy(IR),thermogravimetry(TG)andmassspectroscopy(MS)were performedtoinvestigatethecompositionandthecrystalstructureoftetra-bariumdi-niobate(V) Ba4Nb2O9. TheTG,MSandIRstudiesrevealedthatthecompoundisahydratedoxycarbonate.Assuming that thecarbonatestoichiometricallyreplacesoxygen,thecompositionofthelow-temperature a-modification,obtainedbyslowcoolingfrom1100 1C, correspondstoBa4Nb2O8.8(CO3)0.2 0.1H2O, while thequenchedhigh-temperature g-modificationhastheBa4Nb2O8.42(CO3)0.58 0.38H2O composi- tion. The a-phase hasacompositeincommensuratelymodulatedstructureconsistingoftwomutually interacting[Ba]N and the[(Nb,)O3]N subsystems.Thecompositemodulatedcrystalstructureofthe a-phase canbedescribedwiththelatticeparameters a¼10.2688(1) A˚ , c¼2.82426(8) A˚ , q¼0.66774(2)c* and asuperspacegroup R3m(00g)0s. TheHRTEManalysisdemonstratesthenanoscale twinningofthetrigonaldomainsparalleltothe{100}crystallographicplanes.Thetwinningintroduces a one-dimensionaldisorderintothe[(Nb,)O3]N subsystem,whichresultsinanaverage P62c crystal structureofthe a-phase. Possibleplacesforthecarbonategroupinthestructurearediscussedusinga comparisonwithotherhexagonalperovskite-basedoxycarbonates. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000280620300013 |
Publication Date |
2010-06-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.299; 2010 IF: 2.261 |
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Call Number |
UA @ lucian @ c:irua:84046 |
Serial |
1830 |
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| Permanent link to this record |
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Author |
Yang, C.H.; Peeters, F.M.; Xu, W. |
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Title |
Landau-level broadening due to electron-impurity interaction in graphene in strong magnetic fields |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
82 |
Issue |
7 |
Pages |
075401:1-075401:6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The effect of electron-impurity and electron-electron interactions on the energy spectrum of electrons moving in graphene is investigated in the presence of a high magnetic field. We find that the width of the broadened Landau levels exhibits an approximate 1/B dependence near half filling for charged impurity scattering. The Landau-level width, the density of states, and the Fermi energy exhibit an oscillatory behavior as a function of magnetic field. Comparison with experiment shows that scattering with charged impurities cannot be the main scattering mechanism that determines the width of the Landau levels. |
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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 |
000280553700008 |
Publication Date |
2010-08-04 |
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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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the National Science Foundation of China under Grant No. 10804053, the Foundation of NUIST under Grant No. S8108062001, and the Chinese Academy of Sciences and Department of Science and Technology of Yunnan Province. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:84043 |
Serial |
1769 |
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Author |
Figuerola, A.; van Huis, M.; Zanella, M.; Genovese, A.; Marras, S.; Falqui, A.; Zandbergen, H.W.; Cingolani, R.; Manna, L. |
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Title |
Epitaxial CdSe-Au nanocrystal heterostructures by thermal annealing |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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Volume |
10 |
Issue |
8 |
Pages |
3028-3036 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington |
Editor |
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Language |
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Wos |
000280728900049 |
Publication Date |
2010-07-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1530-6984;1530-6992; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.712 |
Times cited |
112 |
Open Access |
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Notes |
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Approved |
Most recent IF: 12.712; 2010 IF: 12.219 |
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Call Number |
UA @ lucian @ c:irua:83995 |
Serial |
1069 |
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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. |
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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 |
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Volume |
82 |
Issue |
7 |
Pages |
8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000280813100005 |
Publication Date |
2010-08-11 |
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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 |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
58 |
Open Access |
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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 |
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Call Number |
UA @ lucian @ c:irua:83992 |
Serial |
1321 |
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Author |
Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H. |
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Title |
Interplay of atomic displacement in the quantum magnet (CuCI)LaNb2O7 |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
82 |
Issue |
5 |
Pages |
054107,1-054107,12 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic 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 |
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Editor |
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Language |
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Wos |
000280849400001 |
Publication Date |
2010-08-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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| |
Call Number |
UA @ lucian @ c:irua:83991 |
Serial |
1706 |
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| Permanent link to this record |
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Author |
Janssens, K.; Dik, J.; Cotte, M.; Susini, J. |
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Title |
Photon-based techniques for nondestructive subsurface analysis of painted cultural heritage artifacts |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Accounts of chemical research |
Abbreviated Journal |
Accounts Chem Res |
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| |
Volume |
43 |
Issue |
6 |
Pages |
814-825 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
Often, just micrometers below a paintings surface lies a wealth of information, both with Old Masters such as Peter Paul Rubens and Rembrandt van Rijn and with more recent artists of great renown such as Vincent Van Gogh and James Ensor. Subsurface layers may include underdrawing, underpainting, and alterations, and in a growing number of cases conservators have discovered abandoned compositions on paintings, illustrating artists practice of reusing a canvas or panel. The standard methods for studying the inner structure of cultural heritage (CH) artifacts are infrared reflectography and X-ray radiography, techniques that are optionally complemented with the microscopic analysis of cross-sectioned samples. These methods have limitations, but recently, a number of fundamentally new approaches for fully imaging the buildup of hidden paint layers and other complex three-dimensional (3D) substructures have been put into practice. In this Account, we discuss these developments and their recent practical application with CH artifacts. We begin with a tabular summary of 14 IR- and X-ray-based imaging methods and then continue with a discussion of each technique, illustrating CH applications with specific case studies. X-ray-based tomographic and laminographic techniques can be used to generate 3D renditions of artifacts of varying dimensions. These methods are proving invaluable for exploring inner structures, identifying the conservation state, and postulating the original manufacturing technology of metallic and other sculptures. In the analysis of paint layers, terahertz time-domain spectroscopy (THz-TDS) can highlight interfaces between layers in a stratigraphic buildup, whereas macrosopic scanning X-ray fluorescence (MA-XRF) has been employed to measure the distribution of pigments within these layers. This combination of innovative methods provides topographic and color information about the micrometer depth scale, allowing us to look into paintings in an entirely new manner. Over the past five years, several new variants of traditional IR- and X-ray-based imaging methods have been implemented by conservators and museums, and the first reports have begun to emerge in the primary research literature. Applying these state-of-the-art techniques in a complementary fashion affords a more comprehensive view of paintings and other artworks. |
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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 |
000278842500013 |
Publication Date |
2010-05-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0001-4842 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
20.268 |
Times cited |
78 |
Open Access |
|
|
| |
Notes |
; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of FWO (Brussels, Belgium) projects nr. G.0704.08 and G.0179.09 and from the UA-BOF GOA programme. ; |
Approved |
Most recent IF: 20.268; 2010 IF: 21.852 |
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| |
Call Number |
UA @ admin @ c:irua:83983 |
Serial |
5772 |
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| Permanent link to this record |
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Author |
Cotte, M.; Susini, J.; Dik, J.; Janssens, K. |
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| |
Title |
Synchrotron-based X-ray absorption spectroscopy for art conservation: looking back and looking forward |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Accounts of chemical research |
Abbreviated Journal |
Accounts Chem Res |
|
| |
Volume |
43 |
Issue |
6 |
Pages |
705-714 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
A variety of analytical techniques augmented by the use of synchrotron radiation (SR), such as X-ray fluorescence (SR-XRF) and X-ray diffraction (SR-XRD), are now readily available, and they differ little, conceptually, from their common laboratory counterparts. Because of numerous advantages afforded by SR-based techniques over benchtop versions, however, SR methods have become popular with archaeologists, art historians, curators, and other researchers in the field of cultural heritage (CH). Although the CH community now commonly uses both SR-XRF and SR-XRD, the use of synchrotron-based X-ray absorption spectroscopy (SR-XAS) techniques remains marginal, mostly because CH specialists rarely interact with SR physicists. In this Account, we examine the basic principles and capabilities of XAS techniques in art preservation. XAS techniques offer a combination of features particularly well-suited for the chemical analysis of works of art. The methods are noninvasive, have low detection limits, afford high lateral resolution, and provide exceptional chemical sensitivity. These characteristics are highly desirable for the chemical characterization of precious, heterogeneous, and complex materials. In particular, the chemical mapping capability, with high spatial resolution that provides information about local composition and chemical states, even for trace elements, is a unique asset. The chemistry involved in both the objects history (that is, during fabrication) and future (that is, during preservation and restoration treatments) can be addressed by XAS. On the one hand, many studies seek to explain optical effects occurring in historical glasses or ceramics by probing the molecular environment of relevant chromophores. Hence, XAS can provide insight into craft skills that were mastered years, decades, or centuries ago but were lost over the course of time. On the other hand, XAS can also be used to characterize unwanted reactions, which are then considered alteration phenomena and can dramatically alter the objects original visual properties. In such cases, the bulk elemental composition is usually unchanged. Hence, monitoring oxidation state (or, more generally, other chemical modifications) can be of great importance. Recent applications of XAS in art conservation are reviewed and new trends are discussed, highlighting the value (and future possibilities) of XAS, which remains, given its potential, underutilized in the CH community. |
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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 |
000278842500003 |
Publication Date |
2010-01-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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|
| |
ISSN |
0001-4842 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
20.268 |
Times cited |
74 |
Open Access |
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| |
Notes |
; ; |
Approved |
Most recent IF: 20.268; 2010 IF: 21.852 |
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| |
Call Number |
UA @ admin @ c:irua:83982 |
Serial |
5861 |
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| Permanent link to this record |
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Author |
Geurts, R.; Milošević, M.V.; Peeters, F.M. |
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| |
Title |
Vortex matter in mesoscopic two-gap superconducting disks: influence of Josephson and magnetic coupling |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
81 |
Issue |
21 |
Pages |
15 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000278846600001 |
Publication Date |
2010-06-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
89 |
Open Access |
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| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen), the Belgian Science Policy (IAP), the ESF “Nanoscience and Engineering in Superconductivity” (NES) program, and the ESF “Arrays of Quantum Dots and Josephson Junctions” network. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:83933 |
Serial |
3872 |
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| Permanent link to this record |
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Author |
Lorenz, H.; Zhao, Q.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Kloetzer, B.; Rameshan, C.; Pfaller, K. |
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Title |
Origin of different deactivation of Pd/SnO2 and Pd/GeO2 catalysts in methanol dehydrogenation and reforming: a comparative study |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Applied catalysis : A : general |
Abbreviated Journal |
Appl Catal A-Gen |
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| |
Volume |
381 |
Issue |
1/2 |
Pages |
242-252 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Pd particles supported on SnO2 and GeO2 have been structurally investigated by X-ray diffraction, (High-Resolution) transmission and scanning electron microscopy after different reductive treatments to monitor the eventual formation of bimetallic phases and catalytically tested in methanol dehydrogenation/ reforming. For both oxides this included a thin film sample with well-defined Pd particles and a powder catalyst prepared by incipient wetness impregnation. The hexagonal and the tetragonal polymorph were studied for powder GeO2. Pd2Ge formation was observed on all GeO2-supported catalysts, strongly depending on the specific sample used. Reduction of the thin film at 573K resulted in full transformation into the bimetallic state. The partial solubility of hexagonal GeO2 in water and its thermal structural instability yielded Pd2Ge formation at 473 K, at the cost of a structurally inhomogeneous support and Ge metal formation at higher reduction temperatures. Pd on tetragonal GeO2 entered a state of strong metalsupport interaction after reduction at 573673 K, resulting in coalescing Pd2Ge particles on a sintered and re-crystallized support, apparently partially covering the bimetallic particles and decreasing the catalytic activity. Pd2Ge on amorphous thin film and hexagonal GeO2 converted methanol primarily via dehydrogenation to CO and H2. At 573 K, formation of Pd2Sn and also PdSn occurred on the Pd/SnO2 thin film. Pd3Sn2 (and to some extent Pd2Sn) were predominantly obtained on the respective powder catalyst. Strong deactivation with increasing reduction temperature was observed, likely not based on the classical strong metalsupport interaction effect, but rather on a combination of missing active structural ensembles on Sn-enriched bimetallic phases and the formation of metallic -Sn. Correlations to Pd and its bimetallics supported on ZnO, Ga2O3 and In2O3 were also discussed. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000279100700029 |
Publication Date |
2010-04-26 |
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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 |
0926-860X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.339 |
Times cited |
14 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.339; 2010 IF: 3.384 |
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Call Number |
UA @ lucian @ c:irua:83927 |
Serial |
2522 |
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| Permanent link to this record |
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Author |
Ao, Z.M.; Peeters, F.M. |
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Title |
Electric field: A catalyst for hydrogenation of graphene |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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| |
Volume |
96 |
Issue |
25 |
Pages |
3 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Due to the importance of hydrogenation of graphene for several applications, we present an alternative approach to hydrogenate graphene based on density functional theory calculations. We find that a negative perpendicular electric field F can act as a catalyst to reduce the energy barrier for molecular H<sub>2</sub> dissociative adsorption on graphene. Increasing -F above 0.02 a.u. (1 a.u.=5.14×10<sup>11</sup> V/m), this hydrogenation process occurs smoothly without any potential barrier. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000279168100052 |
Publication Date |
2010-06-23 |
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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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
88 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
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Call Number |
UA @ lucian @ c:irua:83924 |
Serial |
881 |
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| Permanent link to this record |
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Author |
Janssens, K.; de Nolf, W.; van der Snickt, G.; Vincze, L.; Vekemans, B.; Terzano, R.; Brenker, F.E. |
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Title |
Recent trends in quantitative aspects of microscopic X-ray fluorescence analysis |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Trends in analytical chemistry |
Abbreviated Journal |
Trac-Trend Anal Chem |
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Volume |
29 |
Issue |
6 |
Pages |
464-478 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000279235000014 |
Publication Date |
2010-03-23 |
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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 |
0165-9936 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.442 |
Times cited |
48 |
Open Access |
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Notes |
; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of FWO (Brussels, Belgium) projects nr. G.0704.08 and G.0179.09 and from the UA-BOF GOA programme. ; |
Approved |
Most recent IF: 8.442; 2010 IF: 6.602 |
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Call Number |
UA @ admin @ c:irua:83903 |
Serial |
5806 |
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| 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. |
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Title |
Insight into the growth of multiple branched MnOOH nanorods |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
10 |
Issue |
7 |
Pages |
2969-2976 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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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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 |
000279422700027 |
Publication Date |
2010-06-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
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 |
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Call Number |
UA @ lucian @ c:irua:83886UA @ admin @ c:irua:83886 |
Serial |
1672 |
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| Permanent link to this record |
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Author |
King, G.; Abakumov, A.M.; Hadermann, J.; Alekseeva, A.M.; Rozova, M.G.; Perkisas, T.; Woodward, P.M.; Van Tendeloo, G.; Antipov, E.V. |
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Title |
Crystal structure and phase transitions in Sr3WO6 |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
49 |
Issue |
13 |
Pages |
6058-6065 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The crystal structures of the beta and gamma polymorphs of Sr3WO6 and the gamma <->beta phase transition have been investigated using electron diffraction, synchrotron X-ray powder diffraction, and neutron powder diffraction. The gamma-Sr3WO6 polymorph is stable above T-c approximate to 470 K and adopts a monoclinically distorted double perovskite A(2)BB'O-6= Sr2SrWO6 structure (space group Cc, a = 10.2363(1)angstrom, b= 17.9007(1)angstrom, c= 11.9717(1)angstrom, beta=125.585(1)degrees at T= 1373 K, Z=12, corresponding to a = a(p)+1/2b(p) – 1/2c(p), b =3/2b(p) + 3/2c(p), c =-b(p) + c(p), a(p),b(p), c(p), lattice vectors of the parent Fm (3) over barm double perovskite structure). Upon cooling it undergoes a continuous phase transition into the triclinically distorted beta-Sr3WO6 phase (space group Cl, a = 10.09497(3)angstrom, b = 17.64748(5)angstrom, c = 11.81400(3)angstrom, alpha = 89.5470(2)degrees, beta= 125.4529(2)degrees, gamma =90.2889(2)degrees at T= 300 K). Both crystal structures of Sr3WO6 belong to a family of double perovskites with broken corner sharing connectivity of the octahedral framework. A remarkable feature of the gamma-Sr3WO6 structure is a non-cooperative rotation of the WO6 octahedra. One third of the WO6 octahedra are rotated by 45 about either the bp or the cp axis of the parent double perovskite structure. As a result, the WO6 octahedra do not share corners but instead share edges with the coordination polyhedra of the Sr cations at the B positions increasing their coordination number from 6 to 7 or 8. The crystal structure of the beta-phase is very close to the structure of the gamma-phase; decreasing symmetry upon the gamma ->beta transformation occurs because of unequal octahedral rotation angles about the bp and cp axes and increasing distortions of the WO6 octahedra. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000279211500036 |
Publication Date |
2010-06-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-1669;1520-510X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
18 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2010 IF: 4.326 |
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Call Number |
UA @ lucian @ c:irua:83877 |
Serial |
562 |
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| Permanent link to this record |
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Author |
Ferreira, W.P.; Farias, G.A.; Peeters, F.M. |
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Title |
A two-component mixture of charged particles confined in a channel: melting |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
22 |
Issue |
28 |
Pages |
11 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The melting of a binary system of charged particles confined in a quasi-one-dimensional parabolic channel is studied through Monte Carlo simulations. At zero temperature the particles are ordered in parallel chains. The melting is anisotropic and different melting temperatures are obtained according to the spatial direction, and the different kinds of particles present in the system. Melting is very different for the single-, two- and four-chain configurations. A temperature induced structural phase transition is found between two different four-chain ordered states which is absent in the mono-disperse system. In the mixed regime, where the two kinds of particles are only slightly different, melting is almost isotropic and a thermally induced homogeneous distribution of the distinct kinds of charges is observed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000279257300023 |
Publication Date |
2010-06-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
10 |
Open Access |
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Notes |
; This work was supported by CNPq, the Flemish Science Foundation (FWO-V1) and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2010 IF: 2.332 |
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Call Number |
UA @ lucian @ c:irua:83862 |
Serial |
3771 |
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Author |
Neek-Amal, M.; Peeters, F.M. |
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Title |
Linear reduction of stiffness and vibration frequencies in defected circular monolayer graphene |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
81 |
Issue |
23 |
Pages |
11 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000279336000001 |
Publication Date |
2010-06-29 |
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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 |
|
Series Issue |
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Edition |
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
44 |
Open Access |
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| |
Notes |
; Financial support was provided by the Hungarian Research Foundation (Contracts No. OTKA K68312, No. K77771, No. K73361, and No. F68726). ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
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Call Number |
UA @ lucian @ c:irua:83857 |
Serial |
1820 |
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| Permanent link to this record |
