Records |
Author |
Austing, D.G.; Payette, C.; Nair, S.V.; Yu, G.; Gupta, J.A.; Partoens, B.; Amaha, S.; Tarucha, S. |
Title |
Scheme for coherently quenching resonant current in a three-level quantum dot energy level mixer |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physica status solidi: C: conferences and critical reviews |
Abbreviated Journal |
|
Volume |
6 |
Issue |
4 |
Pages |
940-943 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We outline a scheme to create a dark state by three-level mixing that is potentially a useful tool for quantum coherent transport. Magnetic-field-induced intra-dot level mixing can lead to rich quantum superposition phenomena between three approaching single-particle states in a quantum dot when probed by the ground state of an adjacent weakly coupled quantum dot in the single-electron resonant tunnelling regime. The mixing relies on non-negligible anharmonicity and anisotropy in confining potentials of realistic quantum dots. Anti-crossing and transfer of strengths between resonances can be understood with a simple coherent level mixing model. Superposition can lead to the formation of a dark state by complete cancellation of an otherwise strong resonance. This is an all-electrical analogue of coherent population trapping seen in three-level-systems from quantum and atom optics. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000266597600040 |
Publication Date |
2008-12-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1862-6351;1610-1642; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:86927 |
Serial |
2953 |
Permanent link to this record |
|
|
|
Author |
Brosens, F.; Magnus, W. |
Title |
Carrier transport in nanodevices: revisiting the Boltzmann and Wigner distribution functions |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
246 |
Issue |
7 |
Pages |
1656-1661 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
In principle, transport of charged carriers in nanometer sized solid-state devices can be fully characterized once the non-equilibrium distribution function describing the carrier ensemble is known. In this light, we have revisited the Boltzmann and the Wigner distribution functions and the framework in which they emerge from the classical respectively quantum mechanical Liouville equation. We have assessed the method of the characteristic curves as a potential workhorse to solve the time dependent Boltzmann equation for carriers propagating through spatially non-uniform systems, such as nanodevices. In order to validate the proposed solution strategy, we numerically solve the Boltzmann equation for a one-dimensional conductor mimicking the basic features of a biased low-dimensional transistor operating in the on-state. Finally, we propose a computational scheme capable of extending the benefits of the above mentioned solution strategy when it comes to solve the Wigner-Liouville equation. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000268659100033 |
Publication Date |
2009-04-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0370-1972;1521-3951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.674 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.674; 2009 IF: 1.150 |
Call Number |
UA @ lucian @ c:irua:77953 |
Serial |
284 |
Permanent link to this record |
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|
|
Author |
Michel, K.H.; Verberck, B. |
Title |
Theoretical phonon dispersions in monolayers and multilayers of hexagonal boron-nitride |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
246 |
Issue |
11/12 |
Pages |
2802-2805 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from an empirical force constant model of valence interactions and calculating by Ewald's method the electrostatic force constants, we derive the dynamical matrix for a monolayer and for multilayer systems of hexagonal boron nitride (h-BN). Solution of the secular problem leads to the corresponding phonon dispersion relations. The interplay between valence forces and Coulomb forces is discussed. A comparison with previous results on graphene and graphene multilayers is made. Our spectra on the h-BN monolayer are rather similar to previous ab initio theory results. Comparison is also made with Raman and infrared experimental results. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000272904100091 |
Publication Date |
2009-11-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0370-1972; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.674 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.674; 2009 IF: 1.150 |
Call Number |
UA @ lucian @ c:irua:80673 |
Serial |
3609 |
Permanent link to this record |
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|
|
Author |
Karabidak, S.M.; Čevik, U.; Kaya, S. |
Title |
A new method to compensate for counting losses due to system dead time |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nuclear instruments and methods in physics research : A: accelerators, spectrometers, detectors and associated equipment |
Abbreviated Journal |
|
Volume |
603 |
Issue |
3 |
Pages |
361-364 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Determination of count losses and pile-up pulse effects in quantitative and qualitative analysis became a vital step in various analyses. Therefore, compensating for counting losses is of importance. These counting losses are due to the pulse pile-up, paralyzable and non-paralyzable system dead time or a combination of these mechanisms. In this work, a new method is suggested for the correction of dead time losses resulting from the above mechanisms. For this purpose, a source code was developed. It was found that the peaking time was an important parameter over system dead time. The method suggested seems to be more effective even at high count rate. (C) 2009 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000266829400021 |
Publication Date |
2009-02-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0168-9002 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:94550 |
Serial |
8304 |
Permanent link to this record |
|
|
|
Author |
Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M. |
Title |
Composite vortex ordering in superconducting films with arrays of blind holes |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
013025,1-013025,20 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The pinning properties of a superconducting thin film with a square array of blind holes are studied using the nonlinear GinzburgLandau theory. Although blind holes provide a weaker pinning potential than holes (also called antidots), several novel vortex structures are predicted for different size and thickness of the blind holes. Orientational dimer and trimer vortex states as well as concentric vortex shells can nucleate in the blind holes. In addition, we predict the stabilization of giant vortices that may be located both in the pinning centers and/or at the interstitial sites, as well as the combination of giant vortices with sets of individual vortices. For large blind holes, local vortex shell structures inside the blind holes may transfer their symmetry to interstitial vortices as well. The subtle interplay of shell formation and traditional Abrikosov vortex lattices inside the blind holes is also studied for different numbers of trapped vortices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000262932600002 |
Publication Date |
2009-01-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
33 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:75987 |
Serial |
441 |
Permanent link to this record |
|
|
|
Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Magnetic Kronig-Penney model for Dirac electrons in single-layer graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
095009,1-095009,21 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
he properties of Dirac electrons in a magnetic superlattice (SL) on graphene consisting of very high and thin (δ-function) barriers are investigated. We obtain the energy spectrum analytically and study the transmission through a finite number of barriers. The results are contrasted with those for electrons described by the Schrödinger equation. In addition, a collimation of an incident beam of electrons is obtained along the direction perpendicular to that of the SL. We also highlight an analogy with optical media in which the refractive index varies in space. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000270513500008 |
Publication Date |
2009-10-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
89 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:79241 |
Serial |
1884 |
Permanent link to this record |
|
|
|
Author |
Bultinck, E.; Bogaerts, A. |
Title |
Particle-in-cell/Monte Carlo collisions treatment of an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx films |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
103010-103010,24 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The physical processes in an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx thin films were simulated with a 2d3v particle-in-cell/Monte Carlo collisions (PIC/MCC) model. The plasma species taken into account are electrons, Ar+ ions, fast Arf atoms, metastable Arm* atoms, Ti+ ions, Ti atoms, O+ ions, O2+ ions, O− ions and O atoms. This model accounts for plasmatarget interactions, such as secondary electron emission and target sputtering, and the effects of target poisoning. Furthermore, the deposition process is described by an analytical surface model. The influence of the O2/Ar gas ratio on the plasma potential and on the species densities and fluxes is investigated. Among others, it is shown that a higher O2 pressure causes the region of positive plasma potential and the O− density to be more spread, and the latter to decrease. On the other hand, the deposition rates of Ti and O are not much affected by the O2/Ar proportion. Indeed, the predicted stoichiometry of the deposited TiOx film approaches x=2 for nearly all the investigated O2/Ar proportions. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000270820900001 |
Publication Date |
2009-10-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
24 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:78326 |
Serial |
2559 |
Permanent link to this record |
|
|
|
Author |
Bultinck, E.; Mahieu, S.; Depla, D.; Bogaerts, A. |
Title |
Reactive sputter deposition of TiNx films, simulated with a particle-in-cell/Monte Carlo collisions model |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
023039,1-023039,24 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The physical processes in an Ar/N2 magnetron discharge used for the reactive sputter deposition of TiNx thin films were simulated with a 2d3v particle-in-cell/Monte Carlo collisions (PIC/MCC) model. Cathode currents and voltages were calculated self-consistently and compared with experiments. Also, ion fractions were calculated and validated with mass spectrometric measurements. With this PIC/MCC model, the influence of N2/Ar gas ratio on the particle densities and fluxes was investigated, taking into account the effect of the poisoned state of the target. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000263744100001 |
Publication Date |
2009-02-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
23 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:73150 |
Serial |
2825 |
Permanent link to this record |
|
|
|
Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
Title |
Vortex matter in oblate mesoscopic superconductors with a hole: broken symmetry vortex states and multi-vortex entry |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
013020,1-013020,21 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using three-dimensional (3D) numerical discretization of the GinzburgLandau (GL) equations, we investigate the superconducting state of a sphere with a piercing hole in the presence of a magnetic field. In the case of samples with central perforation, in axially applied homogeneous magnetic field, we realized unconventional vortex states of broken symmetry due to complex, 3D competing interactions, which depend on the GL parameter ê. For certain sizes of the sample, non-hysteretic multi-vortex entry and exit is predicted with the non-existence of some vorticities as stable states. In a tilted magnetic field, we studied the gradual transformation of 3D flux patterns into 1D vortex chains, where vortices align along the perforation, and the evolvement of the multi-vortex entry as well. We analyze the flux-guiding ability of the hole in a tilted field, which leads to fractional flux response in magnetization M(H) curves. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000262932500003 |
Publication Date |
2009-01-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:75986 |
Serial |
3873 |
Permanent link to this record |
|
|
|
Author |
Tirry, W.; Schryvers, D. |
Title |
Linking a completely three-dimensional nanostrain to a structural transformation eigenstrain |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
Volume |
8 |
Issue |
9 |
Pages |
752-757 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
NiTi is one of the most popular shape-memory alloys, a phenomenon resulting from a martensitic transformation. Commercial NiTi-based alloys are often thermally treated to contain Ni4Ti3 precipitates. The presence of these precipitates can introduce an extra transformation step related to the so-called R-phase. It is believed that the strain field surrounding the precipitates, caused by the matrixprecipitate lattice mismatch, lies at the origin of this intermediate transformation step. Atomic-resolution transmission electron microscopy in combination with geometrical phase analysis is used to measure the elastic strain field surrounding these precipitates. By combining measurements from two different crystallographic directions, the three-dimensional strain matrix is determined from two-dimensional measurements. Comparison of the measured strain matrix to the eigenstrain of the R-phase shows that both are very similar and that the introduction of the R-phase might indeed compensate the elastic strain introduced by the precipitate. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000269215500022 |
Publication Date |
2009-06-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
39.737 |
Times cited |
53 |
Open Access |
|
Notes |
Multimat |
Approved |
Most recent IF: 39.737; 2009 IF: 29.504 |
Call Number |
UA @ lucian @ c:irua:77657 |
Serial |
1822 |
Permanent link to this record |
|
|
|
Author |
Wang, M.; Chang, K.; Wang, L.G.; Dai, N.; Peeters, F.M. |
Title |
Crystallographic plane tuning of charge and spin transport in semiconductor quantum wires |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
20 |
Issue |
36 |
Pages |
365202,1-365202,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate theoretically the charge and spin transport in quantum wires grown along different crystallographic planes in the presence of the Rashba spinorbit interaction (RSOI) and the Dresselhaus spinorbit interaction (DSOI). We find that changing the crystallographic planes leads to a variation of the anisotropy of the conductance due to a different interplay between the RSOI and DSOI, since the DSOI is induced by bulk inversion asymmetry, which is determined by crystallographic plane. This interplay depends sensitively on the crystallographic planes, and consequently leads to the anisotropic charge and spin transport in quantum wires embedded in different crystallographic planes. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000269077000003 |
Publication Date |
2009-08-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.44; 2009 IF: 3.137 |
Call Number |
UA @ lucian @ c:irua:78933 |
Serial |
588 |
Permanent link to this record |
|
|
|
Author |
Zhang, Z.Z.; Wu, Z.H.; Chang, K.; Peeters, F.M. |
Title |
Resonant tunneling through S- and U-shaped graphene nanoribbons |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
20 |
Issue |
41 |
Pages |
415203,1-415203,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We theoretically investigate resonant tunneling through S- and U-shaped nanostructured graphene nanoribbons. A rich structure of resonant tunneling peaks is found emanating from different quasi-bound states in the middle region. The tunneling current can be turned on and off by varying the Fermi energy. Tunability of resonant tunneling is realized by changing the width of the left and/or right leads and without the use of any external gates. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000269930100007 |
Publication Date |
2009-09-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
32 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.44; 2009 IF: 3.137 |
Call Number |
UA @ lucian @ c:irua:79311 |
Serial |
2893 |
Permanent link to this record |
|
|
|
Author |
Zarenia, M.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. |
Title |
Electrostatically confined quantum rings in bilayer graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
Volume |
9 |
Issue |
12 |
Pages |
4088-4092 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We propose a new system where electron and hole states are electrostatically confined into a quantum ring in bilayer graphene. These structures can be created by tuning the gap of the graphene bilayer using nanostructured gates or by position-dependent doping. The energy levels have a magnetic field (B0) dependence that is strikingly distinct from that of usual semiconductor quantum rings. In particular, the eigenvalues are not invariant under a B0 ¨ −B0 transformation and, for a fixed total angular momentum index m, their field dependence is not parabolic, but displays two minima separated by a saddle point. The spectra also display several anticrossings, which arise due to the overlap of gate-confined and magnetically confined states. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Washington |
Editor |
|
Language |
|
Wos |
000272395400023 |
Publication Date |
2009-08-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.712 |
Times cited |
42 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.712; 2009 IF: 9.991 |
Call Number |
UA @ lucian @ c:irua:80318 |
Serial |
1024 |
Permanent link to this record |
|
|
|
Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
Title |
Phonon band structure of Si nanowires: a stability analysis |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
Volume |
9 |
Issue |
1 |
Pages |
107-111 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present full ab initio calculations of the phonon band structure of thin Si nanowires oriented along the [110] direction. Using these phonon dispersion relations, we investigate the structural stability of these wires. We found that all studied wires were stable also when doped with either B or P, if the unit cell was taken sufficiently large along the wire axis. The evolution of the phonon dispersion relations and of the sound velocities with respect to the wire diameters is discussed. Softening is observed for acoustic modes and hardening for optical phonon modes with increasing wire diameters. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington |
Editor |
|
Language |
|
Wos |
000262519100020 |
Publication Date |
2008-12-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.712 |
Times cited |
51 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.712; 2009 IF: 9.991 |
Call Number |
UA @ lucian @ c:irua:76022 |
Serial |
2601 |
Permanent link to this record |
|
|
|
Author |
Van Aert, S.; Verbeeck, J.; Bals, S.; Erni, R.; van Dyck, D.; Van Tendeloo, G. |
Title |
Atomic resolution mapping using quantitative high-angle annular dark field scanning transmission electron microscopy |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
15 |
Issue |
S:2 |
Pages |
464-465 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
Language |
|
Wos |
000208119100230 |
Publication Date |
2009-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.891; 2009 IF: 3.035 |
Call Number |
UA @ lucian @ c:irua:96555UA @ admin @ c:irua:96555 |
Serial |
178 |
Permanent link to this record |
|
|
|
Author |
Bach, D.; Schneider, R.; Gerthsen, D.; Verbeeck, J.; Sigle, W. |
Title |
EELS of niobium and stoichiometric niobium-oxide phases: part 1: plasmon and Near-edges fine structure |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
15 |
Issue |
6 |
Pages |
505-523 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A comprehensive electron energy-loss spectroscopy study of niobium (Nb) and stable Nb-oxide phases (NbO, NbO2, Nb2O5) was carried out. In this work (Part I), the plasmons and energy-loss near-edge structures (ELNES) of all relevant Nb edges (Nb-N2,3, Nb-M4,5, Nb-M2,3, Nb-M1, and Nb-L2,3) up to energy losses of about 2600 eV and the O-K edge are analyzed with respect to achieving characteristic fingerprints of Nb in different formal oxidation states (0 for metallic Nb, +2 for NbO, +4 for NbO2, and +5 for Nb2O5). Chemical shifts of the Nb-N2,3, Nb-M4,5, Nb-M2,3, and Nb-L2,3 edges are extracted from the spectra that amount to about 4 eV as the oxidation state increases from 0 for Nb to +5 for Nb2O5. Four different microscopes, including a 200 keV ZEISS Libra with monochromator, were used. The corresponding wide range of experimental parameters with respect to the primary electron energy, convergence, and collection semi-angles as well as energy resolution allows an assessment of the influence of the experimental setup on the ELNES of the different edges. Finally, the intensity of the Nb-L2,3 white-line edges is correlated with niobium 4d-state occupancy in the different reference materials. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
Language |
|
Wos |
000272433200005 |
Publication Date |
2009-10-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
55 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.891; 2009 IF: 3.035 |
Call Number |
UA @ lucian @ c:irua:80320UA @ admin @ c:irua:80320 |
Serial |
790 |
Permanent link to this record |
|
|
|
Author |
Tian, H.; Schryvers, D.; Shabalovskaya, S.; van Humbeeck, J. |
Title |
Microstructure of surface and subsurface layers of a Ni-Ti shape memory microwire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
15 |
Issue |
|
Pages |
62-70 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The microstructure of a 55 Êm diameter, cold-worked Ni-Ti microwire is investigated by different transmission electron microscopy techniques. The surface consists of a few hundred nanometer thick oxide layer composed of TiO and TiO2 with a small fraction of inhomogeneously distributed Ni. The interior of the wire has a core-shell structure with primarily B2 grains in the 1 Êm thick shell, and heavily twinned B19 martensite in the core. This core-shell structure can be explained by a concentration gradient of the alloying elements resulting in a structure separation due to the strong temperature dependence of the martensitic start temperature. Moreover, in between the B2 part of the metallic core-shell and the oxide layer, a Ni3Ti interfacial layer is detected. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
Language |
|
Wos |
000262912700009 |
Publication Date |
2009-01-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
15 |
Open Access |
|
Notes |
FWO G.0465.05; Multimat |
Approved |
Most recent IF: 1.891; 2009 IF: 3.035 |
Call Number |
UA @ lucian @ c:irua:72319 |
Serial |
2074 |
Permanent link to this record |
|
|
|
Author |
van Oers, C.J.; Stevens, W.J.J.; Bruijn, E.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Meynen, V.; Cool, P. |
Title |
Formation of a combined micro- and mesoporous material using zeolite Beta nanoparticles |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
Volume |
120 |
Issue |
1/2 |
Pages |
29-34 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Composite micro- and mesoporous materials are synthesized using zeolite Beta nanoparticles without the need for a structure directing agent to form the mesopores. This leads to important ecological and economical advantages. The influence of the way of cooling the aged nanoparticles solution on the formation of the composite materials has been studied. The materials have been characterized towards porosity by N2-sorption, towards zeolitic properties by TGA, DRIFT, XRD and TEM, towards aluminium content by EPMA. All prepared structures possess zeolitic properties. However, the method of cooling down of the aged seeds leads to differences in the porosity and intensity of the zeolitic characteristics. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000264619200006 |
Publication Date |
2008-09-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1387-1811; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.615 |
Times cited |
42 |
Open Access |
|
Notes |
Crp; Sfr Ua |
Approved |
Most recent IF: 3.615; 2009 IF: 2.652 |
Call Number |
UA @ lucian @ c:irua:74950 |
Serial |
1254 |
Permanent link to this record |
|
|
|
Author |
Felten, A.; Ghijsen, J.; Pireaux, J.-J.; Drube, W.; Johnson, R.L.; Liang, D.; Hecq, M.; Van Tendeloo, G.; Bittencourt, C. |
Title |
Electronic structure of Pd nanoparticles on carbon nanotubes |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Micron |
Abbreviated Journal |
Micron |
Volume |
40 |
Issue |
1 |
Pages |
74-79 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The effect of the oxygen plasma treatment on the electronic states of multi-wall carbon nanotubes (MWCNTs) is analyzed by X-ray photoemission measurements (XPS) and UPS, both using synchrotron radiation. It is found that the plasma treatment effectively grafts oxygen at the CNT-surface. Thereafter, the interaction between evaporated Pd and pristine or oxygen plasma-treated MWCNTs is investigated. Pd is found to nucleate at defective sites, whether initially present or introduced by oxygen plasma treatment. The plasma treatment induced a uniform dispersion of Pd clusters at the CNT-surface. The absence of additional features in the Pd 3d and C I s core levels spectra testifies that no Pd-C bond is formed. The shift of the Pd 3d core level towards high-binding energy for the smallest clusters is attributed to the Coulomb energy of the charged final state. (C) 2008 Elsevier Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000261420900015 |
Publication Date |
2008-02-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0968-4328; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.98 |
Times cited |
44 |
Open Access |
|
Notes |
Pai 608 |
Approved |
Most recent IF: 1.98; 2009 IF: 1.626 |
Call Number |
UA @ lucian @ c:irua:94578 |
Serial |
1015 |
Permanent link to this record |
|
|
|
Author |
Ruelle, B.; Felten, A.; Ghijsen, J.; Drube, W.; Johnson, R.L.; Liang, D.; Erni, R.; Van Tendeloo, G.; Sophie, P.; Dubois, P.; Godfroid, T.; Hecq, M.; Bittencourt, C.; |
Title |
Functionalization of MWCNTs with atomic nitrogen |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Micron |
Abbreviated Journal |
Micron |
Volume |
40 |
Issue |
1 |
Pages |
85-88 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In this study of the changes induced by exposing MWCNTs to a nitrogen plasma, it was found by HRTEM that the atomic nitrogen exposure does not significantly etch the surface of the carbon nanotube (CNT). Nevertheless, the atomic nitrogen generated by a microwave plasma effectively grafts amine, nitrile, amide, and oxime groups onto the CNT surface, as observed by XPS, altering the density of valence electronic states, as seen in UPS. (C) 2008 Elsevier Ltd. All fights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000261420900017 |
Publication Date |
2008-01-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0968-4328; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.98 |
Times cited |
24 |
Open Access |
|
Notes |
Pai 6/1; Pa 6/27 |
Approved |
Most recent IF: 1.98; 2009 IF: 1.626 |
Call Number |
UA @ lucian @ c:irua:103080 |
Serial |
1305 |
Permanent link to this record |
|
|
|
Author |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
Title |
Adsorption of small molecules on graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
Volume |
40 |
Issue |
4/5 |
Pages |
860-862 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the adsorption process of small molecules on graphene through first-principles calculations and show the presence of two main charge transfer mechanisms. Which mechanism is the dominant one depends on the magnetic properties of the adsorbing molecules. We explain these mechanisms through the density of states of the system and the molecular orbitals of the adsorbates, and demonstrate the possible difficulties in calculating the charge transfer from first principles between a graphene sheet and a molecule. Our results are in good agreement with experiment. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Luton |
Editor |
|
Language |
|
Wos |
000265870200058 |
Publication Date |
2008-12-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-2692; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.163 |
Times cited |
116 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
Call Number |
UA @ lucian @ c:irua:77030 |
Serial |
65 |
Permanent link to this record |
|
|
|
Author |
Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W. |
Title |
Dielectric mismatch effect on coupled impurity states in a freestanding nanowire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
Volume |
40 |
Issue |
3 |
Pages |
446-448 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We studied the coupled impurity states in a freestanding semiconductor nanowire (NW), within the effective mass approximation and including the effect of the dielectric mismatch, by using finite element method. Bonding and anti-bonding states are found and their energies converge with increasing distance di between the two impurities. The dependence of the binding energy on the wire radius R and the distance di between the two impurities is investigated, and we compare it with the result of a freestanding NW that contains a single impurity. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Luton |
Editor |
|
Language |
|
Wos |
000264694700017 |
Publication Date |
2008-07-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-2692; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.163 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
Call Number |
UA @ lucian @ c:irua:76410 |
Serial |
690 |
Permanent link to this record |
|
|
|
Author |
Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M. |
Title |
Neutral shallow donors near a metallic interface |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
Volume |
40 |
Issue |
4/5 |
Pages |
753-755 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of a metallic gate on the bound states of a shallow donor located near the gate is studied. We calculate the energy spectrum as a function of the distance between the metallic gate and the donor and find an anti-crossing behavior in the energy levels for certain distances. We show how a transverse electric field can tune the average position of the electron with respect to the metallic gate and the impurity. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Luton |
Editor |
|
Language |
|
Wos |
000265870200024 |
Publication Date |
2009-02-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-2692; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.163 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
Call Number |
UA @ lucian @ c:irua:77029 |
Serial |
2296 |
Permanent link to this record |
|
|
|
Author |
de Maeyer-Worobiec, A.; Dekov, V.M.; Laane, R.W.P.M.; Van Grieken, R. |
Title |
EPXMA survey of shelf sediments (Southern Bight, North Sea): a glance beyond the XRD-invisible |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microchemical journal |
Abbreviated Journal |
|
Volume |
91 |
Issue |
1 |
Pages |
21-31 |
Keywords |
A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Shelf sediments of the southern North Sea, were studied with a microanalytical [electron probe X-ray microanalysis (EPXMA)] and two bulk [X-ray diffraction (XRD) and X-ray fluorescence (XRF)] techniques. The investigation proved that the promptness of the microanalytical method is combined with a reasonable analytical reliability. XRD studies of such a type of sediments with monotonous mineral composition are not able to provide mineralogical information beyond the main well-crystalline minerals and the mineralogical quantitative characteristic of the sediment based on XRD estimations are incorrect. The EPXMA mineralogical interpretations are based on the statistical evaluation of a huge data set (thousands of mineral particles) and provide a rather correct quantitative determination of the main minerals. The comparative EPXMAXRF study revealed that the Al, Si, K, Ca, Fe and to some extent Ti contents estimated by EPXMA are fairly reliable. In this respect the accuracy of the EPXMA-based mineral identification of the pure silicates, pure aluminosilicates, and Al-, Ca-, Fe- and Ti-containing minerals with simple composition is very high. Mg-calcite, augite and apatite determinations are assessed to be correct. The supposed accuracy of the clay mineral determinations is slightly lower (7080%) than that of the other main minerals due to the complex and varying composition of the clays. The identification of XRD-invisible accessory minerals and quantification of their presence in the sediments is an essential advantage of the EPXMA, which makes it a useful approach in tracing the origin of the sediments, the pathways of their transport and the geochemical processes they have undergone. However, the EPXMA has several flaws, which need to be solved in the future sediment investigations: (1) calibration with natural standards is needed in order to provide a higher accuracy of the mineral determinations; (2) any EPXMA study of sediments needs to be secured with XRF examinations of selected samples since EPXMA gives only semi-quantitative information about the abundance of the elements; (3) ultra-thin window EPXMA of low-Z elements has to be used since some of them (O, C) are always present in the main sediment components: silicates, aluminosilicates, carbonates and metal oxyhydroxides; (4) the interpretations of the clay fraction have to be supported with detailed XRD investigations of selected samples, while the mineralogy of the silt and sand fractions needs to be backed up with optical microscopy studies. The information from different analytical techniques (EPXMA with XRFXRD-optical microscopy of selected samples) combined with the knowledge about the most possible minerals in a given environment, would give the most reliable results in studying mineralogical composition of shelf sediments. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000262963300006 |
Publication Date |
2008-07-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:71604 |
Serial |
7933 |
Permanent link to this record |
|
|
|
Author |
Godoi, R.H.M.; Aerts, K.; Harlay, J.; Kaegi, R.; Ro, C.-U.; Chou, L.; Van Grieken, R. |
Title |
Organic surface coating on Coccolithophores – Emiliania huxleyi: its determination and implication in the marine carbon cycle |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microchemical journal |
Abbreviated Journal |
|
Volume |
91 |
Issue |
2 |
Pages |
266-271 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Most of the marine precipitation of CaCO3 is due to the biological activities of planktonic and benthic organisms in waters largely oversaturated with respect to calcium carbonates. This saturation state is expected to decrease as CO2 increases in seawater. A conventional view in oceanography suggests that calcium carbonates organisms are preserved in oversaturated waters and dissolve only below the lysocline. However, it has be postulated that a fraction of the CaCO3 precipitated biogenically could dissolve in oversaturated waters due to the formation of microenvironments in which respired CO2 decreases the saturation state of seawater (Ù) in the vicinity of CaCO3 crystals. In the present study, cells of the coccolithophore Emiliania huxleyi obtained from laboratory cultures and field samples collected in the Gulf of Biscay, were examined using variable-energy electron-probe microanalysis, to determine the presence and thickness of their organic coating. In addition, a new approach for transferring micrometer-sized particles from a filter onto transmission electron microscope grids using manipulators was used to investigate individual coccolithophores. The dry thickness of an organic coating over the coccolithophore surface was found to range between 280 and 350 nm. The resemblance of this coating to the carbohydrates produced and released by the cell is discussed as well as their potential for constituting a microenvironment that hosts bacteria. The properties of this organic coating and its role in the preservation/dissolution and export of biogenic carbonates in the water column are one of the major issues of carbonate geochemistry. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000264238000020 |
Publication Date |
2009-01-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:73322 |
Serial |
8346 |
Permanent link to this record |
|
|
|
Author |
Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Matsushita, N.; Yoshimura, M.; Guitian, F. |
Title |
Rational synthesis of a nanocrystalline calcium phosphate cement exhibiting rapid conversion to hydroxyapatite |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
Mat Sci Eng C-Mater |
Volume |
29 |
Issue |
7 |
Pages |
2124-2132 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The rational synthesis, comprehensive characterization, and mechanical and micromechanical properties of a calcium phosphate cement are presented. Hydroxyapatite cement biomaterial was synthesized from reactive sub-micrometer-sized dicalcium phosphate dihydrate and tetracalcium phosphate via a dissolution-precipitation reaction using water as the liquid phase. As a result nanostructured, Ca-deficient and carbonated B-type hydroxyapatite is formed. The cement shows good processibility, sets in 22 ± 2 min and entirely transforms to the end product after 6 h of setting reaction, one of the highest conversion rates among previously reported for calcium phosphate cements based on dicalcium and tetracalcium phosphates. The combination of all elucidated physical-chemical traits leads to an essential bioactivity and biocompatibility of the cement, as revealed by in vitro acellular simulated body fluid and cell culture studies. The compressive strength of the produced cement biomaterial was established to be 25 ± 3 MPa. Furthermore, nanoindentation tests were performed directly on the cement to probe its local elasticity and plasticity at sub-micrometer/micrometer level. The measured elastic modulus and hardness were established to be Es = 23 ± 3.5 and H = 0.7 ± 0.2 GPa, respectively. These values are in close agreement with those reported in literature for trabecular and cortical bones, reflecting good elastic and plastic coherence between synthesized cement biomaterial and human bones. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000270159200008 |
Publication Date |
2009-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0928-4931; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.164 |
Times cited |
18 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.164; 2009 IF: NA |
Call Number |
UA @ lucian @ c:irua:79312 |
Serial |
2812 |
Permanent link to this record |
|
|
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Author |
Nowak, D.; Florek, M.; Nowak, J.; Kwiatek, W.; Lekki, J.; Chevallier, P.; Hacura, A.; Wrzalik, R.; Ben-Nissan, B.; Van Grieken, R.; Kuczumow, A. |
Title |
Morphology and the chemical make-up of the inorganic components of black corals |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Materials science and engineering: part C: biomimetic materials |
Abbreviated Journal |
|
Volume |
29 |
Issue |
3 |
Pages |
1029-1038 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Black corals (Cnidaria, Antipatharia) from three different sources were investigated with the aim of detecting inorganic components and their morphology. In general, the skeleton of black corals was composed of the chitin fibrils admixed with peptides and the chitin presence was confirmed by the X-ray diffraction (XRD), Fourier Transformed Infrared Spectrometry (FTIR) and microRaman Microscopy, the latter giving the opportunity of tracing single fibrils and their location. The composition and concentrations of the inorganic components of the black corals were measured, using a scanning electron microprobe and micro-Particle Induced X-ray Emission (µ-PIXE). The application of such instruments enabled the estimation of the constituent distributions in a microscale. The mapping option was the most useful technique of making analyses in these studies, just to reveal the composition of chamber-like cells. Analysis of the morphology and microstructure showed that there were three distinct regions within the coral: a core and the cells encircled with adjacent interface gluing strips. The majority of the elements analyzed were selectively distributed and segregated in a striking way in mentioned distinctive zones of the skeleton and it was detected for the first time. The core area was characterized by the relatively elevated concentrations of Ca. The measurements gave extremely clear images of the distribution of particular elements in the skeletal tissue, with I, Ca, K and Fe much more concentrated in the gluing zones, while C, N, Na and Mg present in the interiors of particular skeletal cells. The distribution of some elements (Mg, Fe) and some compounds (chitin) and functional groups (SS, CI) allows differentiating the biological and mechanical functions of particular fragments of the rods. The kinds of elements and their concentrations measured were essentially in compliance with rare data available in the literature. The Raman technique gave the additional qualitative information about the structure of gluing zone and the chitin fibrils and surrounding matrix inside the cell interior. |
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 |
000266520400065 |
Publication Date |
2008-09-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0928-4931 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:76024 |
Serial |
8284 |
Permanent link to this record |
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Author |
Mortet, V.; Zhang, L.; Echert, M.; Soltani, A.; d' Haen, J.; Douheret, O.; Moreau, M.; Osswald, S.; Neyts, E.; Troadec, D.; Wagner, P.; Bogaerts, A.; Van Tendeloo, G.; Haenen, K. |
Title |
Characterization of nano-crystalline diamond films grown under continuous DC bias during plasma enhanced chemical vapor deposition |
Type |
A3 Journal article |
Year |
2009 |
Publication |
Materials Research Society symposium proceedings |
Abbreviated Journal |
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Volume |
|
Issue |
1203 |
Pages |
|
Keywords |
A3 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Nanocrystalline diamond films have generated much interested due to their diamond-like properties and low surface roughness. Several techniques have been used to obtain a high re-nucleation rate, such as hydrogen poor or high methane concentration plasmas. In this work, the properties of nano-diamond films grown on silicon substrates using a continuous DC bias voltage during the complete duration of growth are studied. Subsequently, the layers were characterised by several morphological, structural and optical techniques. Besides a thorough investigation of the surface structure, using SEM and AFM, special attention was paid to the bulk structure of the films. The application of FTIR, XRD, multi wavelength Raman spectroscopy, TEM and EELS yielded a detailed insight in important properties such as the amount of crystallinity, the hydrogen content and grain size. Although these films are smooth, they are under a considerable compressive stress. FTIR spectroscopy points to a high hydrogen content in the films, while Raman and EELS indicate a high concentration of sp2 carbon. TEM and EELS show that these films consist of diamond nano-grains mixed with an amorphous sp2 bonded carbon, these results are consistent with the XRD and UV Raman spectroscopy data. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Wuhan |
Editor |
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Language |
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Wos |
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Publication Date |
2010-03-27 |
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 |
1946-4274; |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
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Open Access |
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Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:81646 |
Serial |
327 |
Permanent link to this record |
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|
Author |
Verstraelen, H.; de Baere, K.; Schillemans, W.; Lemmens, L.; Dewil, R.; Lenaerts, S.; Potters, G. |
Title |
In situ study of ballast tank corrosion on ships: part 1 |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Materials performance |
Abbreviated Journal |
Mater Performance |
Volume |
48 |
Issue |
10 |
Pages |
48-51 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Theory of quantum systems and complex systems; Sustainable Energy, Air and Water Technology (DuEL) |
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 |
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Publication Date |
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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 |
0094-1492 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
Impact Factor |
0.149 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 0.149; 2009 IF: 0.124 |
Call Number |
UA @ admin @ c:irua:78547 |
Serial |
5963 |
Permanent link to this record |
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Author |
Verstraelen, H.; de Baere, K.; Schillemans, W.; Lemmens, L.; Dewil, R.; Lenaerts, S.; Potters, G. |
Title |
In situ study of ballast tank corrosion on ships: part 2 |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Materials performance |
Abbreviated Journal |
Mater Performance |
Volume |
48 |
Issue |
11 |
Pages |
54-57 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Theory of quantum systems and complex systems; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
A study was undertaken to determine causes and effects of corrosion processes in ballast tanks. Part 1 of this article (October 2009 MP) described the data collection. Part 2 describes the development of a corrosion index (CI) derived from the general International Association of Classification Societies corrosion assessment methods. The CI can be used in situ to assess ballast tank corrosion. An average timeline for-corrosion of tanks is presented. |
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 |
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Publication Date |
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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 |
0094-1492 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.149 |
Times cited |
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Open Access |
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Notes |
|
Approved |
Most recent IF: 0.149; 2009 IF: 0.124 |
Call Number |
UA @ admin @ c:irua:79761 |
Serial |
5964 |
Permanent link to this record |