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Records |
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Author |
Georgieva, V.; Saraiva, M.; Jehanathan, N.; Lebelev, O.I.; Depla, D.; Bogaerts, A. |
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Title |
Sputter-deposited Mg-Al-O thin films: linking molecular dynamics simulations to experiments |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
42 |
Issue |
6 |
Pages |
065107,1-065107,8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Using a molecular dynamics model the crystallinity of MgxAlyOz thin films with a variation in the stoichiometry of the thin film is studied at operating conditions similar to the experimental operating conditions of a dual magnetron sputter deposition system. The films are deposited on a crystalline or amorphous substrate. The Mg metal content in the film ranged from 100% (i.e. MgO film) to 0% (i.e. Al2O3 film). The radial distribution function and density of the films are calculated. The results are compared with x-ray diffraction and transmission electron microscopy analyses of experimentally deposited thin films by the dual magnetron reactive sputtering process. Both simulation and experimental results show that the structure of the MgAlO film varies from crystalline to amorphous when the Mg concentration decreases. It seems that the crystalline MgAlO films have a MgO structure with Al atoms in between. |
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Corporate Author |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000263824200024 |
Publication Date |
2009-03-03 |
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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 |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
37 |
Open Access |
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Notes |
Iwt |
Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
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Call Number |
UA @ lucian @ c:irua:73246 |
Serial |
3110 |
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Permanent link to this record |
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Author |
Petrović, D.; Martens, T.; van Dijk, J.; Brok, W.J.M.; Bogaerts, A. |
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Title |
Fluid modelling of an atmospheric pressure dielectric barrier discharge in cylindrical geometry |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
42 |
Issue |
20 |
Pages |
205206,1-205206,12 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A numerical parameter study has been performed for a cylindrical atmospheric pressure dielectric barrier discharge (DBD) in helium with nitrogen impurities using a two-dimensional time-dependent fluid model. The calculated electric currents and gap voltages as a function of time for a given applied potential are presented, as well as the number densities of the various plasma species. This study shows that for the geometry under consideration the applied voltage parameters have a large impact on the electric current profiles and that the discharge current is always determined by the electron and ion conduction currents while the displacement current is nearly negligible. A relative broadening of the current profiles (compared with the duration of the half cycle of the applied voltage) with an increase in the applied frequency is obtained. Nearly sinusoidal current wave forms, usually typical for radio frequency DBDs, are observed while still operating at the frequencies of tens of kilohertz. For the setup under investigation, the Townsend mode of the DBD is observed in the entire range of applied voltage amplitudes and frequencies. It is shown that the average power density dissipated in the discharge increases with rising applied voltage and frequency. An increase in applied voltage frequency leads to an increase in the electron density and a decrease in electron energy, while increasing the voltage amplitude has the opposite effect. |
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Corporate Author |
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Thesis |
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Place of Publication |
London |
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Language |
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Wos |
000270563200028 |
Publication Date |
2009-09-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
29 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
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Call Number |
UA @ lucian @ c:irua:78202 |
Serial |
1228 |
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Permanent link to this record |
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Author |
Bogaerts, A.; Bultinck, E.; Kolev, I.; Schwaederlé, L.; van Aeken, K.; Buyle, G.; Depla, D. |
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Title |
Computer modelling of magnetron discharges |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
42 |
Issue |
19 |
Pages |
194018,1-194018,12 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this paper, some modelling approaches to describe direct current (dc) magnetron discharges developed in our research groups will be presented, including an analytical model, Monte Carlo simulations for the electrons and for the sputtered atoms, a hybrid Monte Carlo-fluid model and particle-in-cell-Monte Carlo collision simulations. The strengths and limitations of the various modelling approaches will be explained, and some characteristic simulation results will be illustrated. Furthermore, some other simulation methods related to the magnetron device will be briefly explained, more specifically for calculating the magnetic field distribution inside the discharge, and for describing the (reactive) sputtering. |
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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 |
000269993100020 |
Publication Date |
2009-09-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
32 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
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Call Number |
UA @ lucian @ c:irua:78168 |
Serial |
462 |
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Permanent link to this record |
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Author |
van Dijk, J.; Kroesen, G.M.W.; Bogaerts, A. |
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Title |
Plasma modelling and numerical simulation |
Type |
Editorial |
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Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
42 |
Issue |
19 |
Pages |
190301,1-190301,14 |
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Keywords |
Editorial; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma modelling is an exciting subject in which virtually all physical disciplines are represented. Plasma models combine the electromagnetic, statistical and fluid dynamical theories that have their roots in the 19th century with the modern insights concerning the structure of matter that were developed throughout the 20th century. The present cluster issue consists of 20 invited contributions, which are representative of the state of the art in plasma modelling and numerical simulation. These contributions provide an in-depth discussion of the major theories and modelling and simulation strategies, and their applications to contemporary plasma-based technologies. In this editorial review, we introduce and complement those papers by providing a bird's eye perspective on plasma modelling and discussing the historical context in which it has surfaced. |
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Corporate Author |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000269993100001 |
Publication Date |
2009-09-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
64 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
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Call Number |
UA @ lucian @ c:irua:78166 |
Serial |
2637 |
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Permanent link to this record |
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Author |
Martens, T.; Brok, W.J.M.; van Dijk, J.; Bogaerts, A. |
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Title |
On the regime transitions during the formation of an atmospheric pressure dielectric barrier glow discharge |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
42 |
Issue |
12 |
Pages |
122002,1-122002,5 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The atmospheric pressure dielectric barrier discharge in helium is a pulsed discharge in nature. If during the electrical current pulse a glow discharge is reached, then this pulse will last only a few microseconds in operating periods of sinusoidal voltage with lengths of about 10 to 100 µs. In this paper we demonstrate that right before a glow discharge is reached, the discharge very closely resembles the commonly assumed Townsend discharge structure, but actually contains some significant differing features and hence should not be considered as a Townsend discharge. In order to clarify this, we present calculation results of high time and space resolution of the pulse formation. The results indicate that indeed a maximum of ionization is formed at the anode, but that the level of ionization remains high and that the electric field at that time is significantly disturbed. Our results also show where this intermediate structure comes from. |
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Corporate Author |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000266639300002 |
Publication Date |
2009-05-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
21 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
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Call Number |
UA @ lucian @ c:irua:76458 |
Serial |
2450 |
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Permanent link to this record |
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Author |
Matthai, C.C.; March, N.H.; Lamoen, D. |
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Title |
Supercooled molecular liquids and the glassy phases of chemically bonded N, P, As, Si and Ge |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physics and chemistry of liquids |
Abbreviated Journal |
Phys Chem Liq |
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Volume |
47 |
Issue |
6 |
Pages |
607-613 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Glassy phases which have insulating character exist for a variety of monatomic species. By contrast, until recently, it has been possible to make bulk metallic glasses (BMG) by vitrification only for multicomponent systems. After a relatively brief summary on supercooling of a few molecular liquids, we review some of the recently reported results on molecular assemblies of the series N, P, As and amorphous Si and Ge. Based on these results, we suggest that the transition metals with their directional bonding might be suitable candidates for the production of BMG by vitrification. |
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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 |
000273047400003 |
Publication Date |
2009-11-10 |
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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 |
0031-9104;1029-0451; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.145 |
Times cited |
1 |
Open Access |
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Notes |
BoF |
Approved |
Most recent IF: 1.145; 2009 IF: 0.580 |
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Call Number |
UA @ lucian @ c:irua:80653 |
Serial |
3376 |
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Permanent link to this record |
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Author |
Masir, M.R.; Vasilopoulos, P.; Matulis, A.; Peeters, F.M. |
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Title |
Angular confinement and direction-dependent transmission in graphene nanostructures with magnetic barriers |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
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Volume |
1199 |
Issue |
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Pages |
363-364 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We evaluate the transmission through magnetic barriers in graphene-based nanostructures. Several particular cases are considered: a magnetic step, single and double barriers, delta -function barriers as well as barrier structures with inhomogeneous magnetic field profiles but with average magnetic field equal to zero. The transmission exhibits a strong dependence on the direction of the incident wave vector. In general the resonant structure of the transmission is significantly more pronounced for (Dirac) electrons with linear spectrum compared to that for electrons with a parabolic one. |
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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 |
Editor |
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Language |
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Wos |
000281590800171 |
Publication Date |
2010-01-15 |
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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 |
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ISBN |
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Additional Links |
UA library record; WoS full record |
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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 |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:84892 |
Serial |
115 |
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Permanent link to this record |
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Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
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Title |
Phonon band structures of Si nanowires |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
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Volume |
1199 |
Issue |
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Pages |
323-324 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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. |
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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 |
Editor |
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Language |
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Wos |
000281590800153 |
Publication Date |
2010-01-15 |
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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 |
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ISBN |
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Additional Links |
UA library record; WoS full record |
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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 |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:84891 |
Serial |
2602 |
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Permanent link to this record |
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Author |
Zhang, Y.; Fischetti, M.V.; Sorée, B.; Magnus, W.; Heyns, M.; Meuris, M. |
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Title |
Physical modeling of strain-dependent hole mobility in Ge p-channel inversion layers |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
106 |
Issue |
8 |
Pages |
083704,1-083704,9 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We present comprehensive calculations of the low-field hole mobility in Ge p-channel inversion layers with SiO2 insulator using a six-band k·p band-structure model. The cases of relaxed, biaxially, and uniaxially (both tensily and compressively) strained Ge are studied employing an efficient self-consistent methodmaking use of a nonuniform spatial mesh and of the Broyden second methodto solve the coupled envelope-wave function k·p and Poisson equations. The hole mobility is computed using the KuboGreenwood formalism accounting for nonpolar hole-phonon scattering and scattering with interfacial roughness. Different approximations to handle dielectric screening are also investigated. As our main result, we find a large enhancement (up to a factor of 10 with respect to Si) of the mobility in the case of uniaxial compressive stress similarly to the well-known case of Si. Comparison with experimental data shows overall qualitative agreement but with significant deviations due mainly to the unknown morphology of the rough Ge-insulator interface, to additional scattering with surface optical phonon from the high- insulator, to Coulomb scattering interface traps or oxide chargesignored in our calculationsand to different channel structures employed. |
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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 |
000271358100050 |
Publication Date |
2009-10-20 |
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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 |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
29 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:80137 |
Serial |
2617 |
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Permanent link to this record |
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Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
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Title |
Phonons in Ge nanowires |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
95 |
Issue |
12 |
Pages |
122110,1-122110,3 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The phonon spectra of thin freestanding, hydrogen passivated, Ge nanowires are calculated by ab initio techniques. The effect of confinement on the phonon modes as caused by the small diameters of the wires is investigated. Confinement causes a hardening of the optical modes and a softening of the longitudinal acoustic modes. The stability of the nanowires, undoped or doped with B or P atoms, is investigated using the obtained phonon spectra. All considered wires were stable, except for highly doped, very thin nanowires. |
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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 |
000270243800035 |
Publication Date |
2009-09-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.411; 2009 IF: 3.554 |
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Call Number |
UA @ lucian @ c:irua:79307 |
Serial |
2606 |
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Permanent link to this record |
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Author |
Castelano, L.K.; Hai, G.Q.; Partoens, B.; Peeters, F.M. |
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Title |
Artificial molecular quantum rings under magnetic field influence |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
106 |
Issue |
7 |
Pages |
073702,1-073702,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The ground states of a few electrons confined in two vertically coupled quantum rings in the presence of an external magnetic field are studied systematically within the current spin-density functional theory. Electron-electron interactions combined with inter-ring tunneling affect the electronic structure and the persistent current. For small values of the external magnetic field, we recover the zero magnetic field molecular quantum ring ground state configurations. Increasing the magnetic field many angular momentum, spin, and isospin transitions are predicted to occur in the ground state. We show that these transitions follow certain rules, which are governed by the parity of the number of electrons, the single-particle picture, Hunds rules, and many-body effects. |
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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 |
000270915600047 |
Publication Date |
2009-10-03 |
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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 |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:86926 |
Serial |
155 |
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Permanent link to this record |
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Author |
Dhong, H.M.; Zhang, J.; Peeters, F.M.; Xu, W. |
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Title |
Optical conductance and transmission in bilayer graphene |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
106 |
Issue |
4 |
Pages |
043103,1-043103,6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We present a theoretical study of the optoelectronic properties of bilayer graphene. The optical conductance and transmission coefficient are calculated using the energy-balance equation derived from a Boltzmann equation for an air/graphene/dielectric-wafer system. For short wavelengths (<0.2 µm), we obtain the universal optical conductance =e2/(2). Interestingly, there exists an optical absorption window in the wavelength range 10100 µm, which is induced by different transition energies required for inter- and intra-band optical absorptions in the presence of the MossBurstein effect. As a result, the position and width of this absorption window depend sensitively on temperature, carrier density, and sample mobility of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors. |
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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 |
000270083800004 |
Publication Date |
2009-08-20 |
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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 |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
11 |
Open Access |
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|
|
Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:79315 |
Serial |
2472 |
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Permanent link to this record |
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Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
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Title |
Ballistic current in metal-oxide-semiconductor field-effect transistors: the role of device topology |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
106 |
Issue |
5 |
Pages |
053702,1-053702,8 |
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|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this study we investigate the effect of device topology on the ballistic current in n-channel metal-oxide-semiconductor field-effect transistors. Comparison of the nanoscale planar and double-gate devices reveals that, down to a certain thickness of the double gate film, the ballistic current flowing in the double gate device is twice as large compared to its planar counterpart. On the other hand, further thinning of the film beyond this threshold is found to change noticeably the confinement and transport characteristics, which are strongly depending on the film material and the surface orientation. For double gate Ge and Si devices there exists a critical film thickness below which the transverse gate field is no longer effectively screened by the inversion layer electron gas and mutual inversion of the two gates is turned on. In the case of GaAs and other similar IIIV compounds, a decrease in the film thickness may drastically change the occupation of the L-valleys and therefore amend the transport properties. The simulation results show that, in both cases, the ballistic current and the transconductance are considerably enhanced. |
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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 |
|
Wos |
000269850300052 |
Publication Date |
2009-09-03 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:79744 |
Serial |
214 |
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Permanent link to this record |
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Author |
Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A. |
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Title |
Modified atomic scattering amplitudes and size effects on the 002 and 220 electron structure factors of multiple Ga1-xInxAs/GaAs quantum wells |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
105 |
Issue |
8 |
Pages |
084310,1-084310,8 |
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|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The modified atomic scattering amplitudes (MASAs) of mixed Ga<sub>1-x</sub>In<sub>x</sub>As, GaAs<sub>1-x</sub>N<sub>x</sub>, and InAs<sub>1-x</sub>N<sub>x</sub> are calculated using the density functional theory approach and the results are compared with those of the binary counterparts. The MASAs of N, Ga, As, and In for various scattering vectors in various chemical environments and in the zinc-blende structure are compared with the frequently used Doyle and Turner values. Deviation from the Doyle and Turner results is found for small scattering vectors (s<0.3 Å<sup>-1</sup>) and for these scattering vectors the MASAs are found to be sensitive to the orientation of the scattering vector and on the chemical environment. The chemical environment sensitive MASAs are used within zero pressure classical Metropolis Monte Carlo, finite temperature calculations to investigate the effect of well size on the electron 002 and 220 structure factors (SFs). The implications of the use of the 002 (200) spot for the quantification of nanostructured Ga<sub>1-x</sub>In<sub>x</sub>As systems are examined while the 220 SF across the well is evaluated and is found to be very sensitive to the in-plane static displacements. |
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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 |
000268064700149 |
Publication Date |
2009-04-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.068 |
Times cited |
|
Open Access |
|
|
|
Notes |
Fwo G.0425.05; Esteem 026019 |
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:78282 |
Serial |
2160 |
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Permanent link to this record |
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Author |
Verberck, B.; Vliegenthart, G.A.; Gompper, G. |
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Title |
Orientational ordering in solid C60 fullerene-cubane |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
130 |
Issue |
15 |
Pages |
154510,1-154510,14 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study the structure and phase behavior of fullerene-cubane C60·C8H8 by Monte Carlo simulation. Using a simple potential model capturing the icosahedral and cubic symmetries of its molecular constituents, we reproduce the experimentally observed phase transition from a cubic to an orthorhombic crystal lattice and the accompanying rotational freezing of the C60 molecules. We elaborate a scheme to identify the low-temperature orientations of individual molecules and to detect a pattern of orientational ordering similar to the arrangement of C60 molecules in solid C60. Our configuration of orientations supports a doubled periodicity along one of the crystal axes. |
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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 |
|
Wos |
000265486300036 |
Publication Date |
2009-04-22 |
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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 |
0021-9606; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.965 |
Times cited |
8 |
Open Access |
|
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Notes |
|
Approved |
Most recent IF: 2.965; 2009 IF: 3.093 |
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Call Number |
UA @ lucian @ c:irua:77258 |
Serial |
2519 |
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Permanent link to this record |
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Author |
Tirry, W.; Schryvers, D. |
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Title |
3D strain fields surrounding Ni4Ti3: direct measurement and correlation with the R-phase |
Type |
P1 Proceeding |
|
Year |
2009 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
02032,1-02032,6 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
Strain fields introduced by coherent Ni4Ti3 precipitates in austenitic Ni-Ti are believed to be a possible origin of why the R-phase transformation is introduced as an extra step before transforming to the B19'. The presence of this strain field was already confirmed in the past by conventional transmission electron microscopy (TEM) techniques and measured quantitatively by high resolution TEM (HRTEM). This time the geometrical phase method is applied on HRTEM micrographs to measure the full 3D strain tensor of the strain fields. Since each atomic resolution micrograph only results in a 2D measurement of the strain, observations in two different zone orientations are combined to retrieve the 3 x 3 strain tensor. In this work observations in a [1-1 1](B2) and [1 0-1](B2) zone orientation are used and this in case of precipitates with a diameter of around 50nm. In a next step the measured strain tensor is compared to the calculated eigenstrain of the R-phase in reference to the B2 matrix. This comparison shows that the introduced strain is very similar to the eigenstrain of one R-phase variant. Since for both structures, Ni4Ti3 and R-phase, four orientation variants are possible, each variant of the R-phase is thus able to accommodate the strain field of one of the Ni4Ti3 variants. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Edp |
Place of Publication |
Coutaboeuf |
Editor |
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Language |
|
Wos |
000274582300036 |
Publication Date |
2009-08-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
|
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:81953 |
Serial |
17 |
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Permanent link to this record |
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Author |
Delville, R.; James, R.D.; Salman, U.; Finel, A.; Schryvers, D. |
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Title |
Transmission electron microscopy study of low-hysteresis shape memory alloys |
Type |
P1 Proceeding |
|
Year |
2009 |
Publication |
|
Abbreviated Journal |
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Volume |
|
Issue |
|
Pages |
02005,1-02005,7 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
Recent findings have linked low hysteresis in shape memory alloys with phase compatibility between austenite and martensite. In order to investigate the evolution of microstructure as the phase compatibility increases and the hysteresis is reduced, transmission electron microscopy was used to study the alloy system Ti50Ni50-xPdx where the composition is systemically tuned to approach perfect compatibility. Changes in morphology, twinning density and twinning modes are reported along with special microstructures occurring when the compatibility is achieved. In addition, the interface between austenite and a single variant of martensite was studied by high-resolution and conventional electron microscopy. The atomically sharp, defect free, low energy configuration of the interface suggests that it plays an important role in the lowering of hysteresis. Finally, dynamical modeling of the martensitic transformation using the phase-field micro-elasticity model within the geometrically linear theory succeeded in reproducing the change in microstructure as the compatibility condition is satisfied. Latest results on the extension of these findings in other Ni-Ti based ternary/quaternary systems are also reported. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Edp |
Place of Publication |
Coutaboeuf |
Editor |
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Language |
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Wos |
000274582300009 |
Publication Date |
2009-08-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
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Impact Factor |
|
Times cited |
3 |
Open Access |
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Notes |
|
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:81951 |
Serial |
3716 |
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Permanent link to this record |
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Author |
Cao, S.; Nishida, M.; Somsen, C.; Eggeler, G.; Schryvers, D. |
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Title |
3D FIB/SEM study of Ni4Ti3 precipitates in Ni-Ti alloys with different thermal-mechanical histories |
Type |
P1 Proceeding |
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Year |
2009 |
Publication |
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Abbreviated Journal |
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Volume |
|
Issue |
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Pages |
02004,1-02004,6 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
The three-dimensional size, morphology and distribution of Ni4Ti3 precipitates growing in binary Ni-rich Ni-Ti alloys have been investigated via a slice view procedure in a Dual-Beam FIB/SEM system, in order to better stress-free Ni50.8Ti49.2 alloy with all four variants of precipitates and a compressed Ni51Ti49 alloy with aligned precipitates in one family were studied. The Ni4Ti3 precipitates reach a volume fraction of 9.6% in the reconstructed region of the stress-free alloy and 4.3% in the compressed one. In both cases, the mean volume, specific surface area, sphericity and aspect ratio of the precipitates are calculated and the Pair Distribution Functions of the precipitates are obtained. It is shown that most precipitates in the stress-free sample grow larger and have a more lenticular shape, while those in the compressed sample are more cylindrical. Deviations from these ideal shapes reveal internal steps in the stress-free sample and lamellae formation in the compressed one. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Edp |
Place of Publication |
Coutaboeuf |
Editor |
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Language |
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Wos |
000274582300008 |
Publication Date |
2009-08-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:81950 c:irua:81950 |
Serial |
14 |
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Permanent link to this record |
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Author |
Verlooy, P.; Aerts, A.; Lebedev, O.I.; Van Tendeloo, G.; Kirschhock, C.; Martens, J.A. |
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Title |
Synthesis of highly stable pure-silica thin-walled hexagonally ordered mesoporous material |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Chemical communications |
Abbreviated Journal |
Chem Commun |
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Volume |
|
Issue |
28 |
Pages |
4287-4289 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Hexagonally ordered mesoporous silica with a very narrow mesopore size distribution and exceptionally high stability paired with unusually thin pore walls was prepared using piperidine and cetyltrimethylammonium bromide. |
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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 |
000267808000040 |
Publication Date |
2009-06-09 |
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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 |
1359-7345;1364-548X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.319 |
Times cited |
17 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 6.319; 2009 IF: 5.504 |
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Call Number |
UA @ lucian @ c:irua:77684 |
Serial |
3457 |
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Permanent link to this record |
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Author |
Hamelet, S.; Gibot, P.; Casas-Cabanas, M.; Bonnin, D.; Grey, C.P.; Cabana, J.; Leriche, J.B.; Rodriguez-Carvajal, J.; Courty, M.; Levasseur, S.; Carlach, P.; Van Thournout, M.; Tarascon, J.M.; Masquelier, C.; |
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Title |
The effects of moderate thermal treatments under air on LiFePO4-based nano powders |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
19 |
Issue |
23 |
Pages |
3979-3991 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The thermal behavior under air of LiFePO(4)-based powders was investigated through the combination of several techniques such as temperature-controlled X-ray diffraction, thermogravimetric analysis and Mossbauer and NMR spectroscopies. The reactivity with air at moderate temperatures depends on the particle size and leads to progressive displacement of Fe from the core structure yielding nano-size Fe(2)O(3) and highly defective, oxidized Li(x)Fe(y)PO(4) compositions whose unit-cell volume decreases dramatically when the temperature is raised between 400 and 600 K. The novel LiFePO(4)-like compositions display new electrochemical reactivity when used as positive electrodes in Li batteries. Several redox phenomena between 3.4 V and 2.7 V vs. Li were discovered and followed by in-situ X-ray diffraction, which revealed two distinct solid solution domains associated with highly anisotropic variations of the unit-cell constants. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000266615800024 |
Publication Date |
2009-05-05 |
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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 |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
93 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:94582 |
Serial |
867 |
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Permanent link to this record |
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Author |
Mandal, T.K.; Croft, M.; Hadermann, J.; Van Tendeloo, G.; Stephens, P.W.; Greenblatt, M. |
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Title |
La2MnVO6 double perovskite: a structural, magnetic and X-ray absorption investigation |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
19 |
Issue |
25 |
Pages |
4382-4390 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The synthesis, electron diffraction (ED), synchrotron X-ray and neutron structure, X-ray absorption spectroscopy (XAS) and magnetic property studies of La2MnVO6 double perovskite are described. Analysis of the synchrotron powder X-ray diffraction data for La2MnVO6 indicates a disordered arrangement of Mn and V at the B-site of the perovskite structure. Absence of super-lattice reflections in the ED patterns for La2MnVO6 supports the disordered cation arrangement. Room temperature time-of-flight (TOF) neutron powder diffraction (NPD) data show no evidence of cation ordering, in corroboration with the ED and synchrotron studies (orthorhombic Pnma, a = 5.6097(3), b = 7.8837(5) and c = 5.5668(3) ; 295 K, NPD). A comparison of XAS analyses of La2TVO6 with T = Ni and Co shows T2+ formal oxidation state while the T = Mn material evidences a Mn3+ admixture into a dominantly Mn2+ ground state. V-K edge measurements manifest a mirror image behavior with a V4+ state for T = Ni and Co with a V3+ admixture arising in the T = Mn material. The magnetic susceptibility data for La2MnVO6 show ferromagnetic correlations; the observed effective moment, µeff (5.72 µB) is much smaller than the calculated moment (6.16 µB) based on the spin-only formula for Mn2+ (d5, HS) /V4+ (d1), supportive of the partly oxidized Mn and reduced V scenario (Mn3+/V3+). |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000266989800015 |
Publication Date |
2009-04-24 |
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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 |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:77367 |
Serial |
3540 |
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Permanent link to this record |
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Author |
Eckert, M.; Neyts, E.; Bogaerts, A. |
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Title |
Modeling adatom surface processes during crystal growth: a new implementation of the Metropolis Monte Carlo algorithm |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
CrystEngComm |
Abbreviated Journal |
Crystengcomm |
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Volume |
11 |
Issue |
8 |
Pages |
1597-1608 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this paper, a new implementation of the Metropolis Monte Carlo (MMC) algorithm is presented. When combining the MMC model with a molecular dynamics (MD) code, crystal growth by plasma-enhanced chemical vapor deposition can be simulated. As the MD part simulates impacts of growth species onto the surface on a time scale of picoseconds, the MMC algorithm simulates the slower adatom surface processes. The implementation includes a criterion for the selection of atoms that are allowed to be displaced during the simulation, and a criterion of after how many MMC cycles the simulation is stopped. We performed combined MD-MMC simulations for hydrocarbon species that are important for the growth of ultrananocrystalline diamond (UNCD) films at partially hydrogenated diamond surfaces, since this implementation is part of a study of the growth mechanisms of (ultra)nanocrystalline diamond films. Exemplary for adatom arrangements during the growth of UNCD, the adatom surface behavior of C and C2H2 at diamond (111)1 × 1, C and C4H2 at diamond (111)1 × 1 and C3 at diamond (100)2 × 1 has been investigated. For all cases, the diamond crystal structure is pursued under the influence of MMC simulation. Additional longer time-scale MD simulations put forward very similar structures, verifying the MMC algorithm. Nevertheless, the MMC simulation time is typically one order of magnitude shorter than the MD simulation time. |
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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 |
000268184300021 |
Publication Date |
2009-04-07 |
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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 |
|
Series Issue |
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Edition |
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ISSN |
1466-8033; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
3.474 |
Times cited |
15 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.474; 2009 IF: 4.183 |
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Call Number |
UA @ lucian @ c:irua:77374 |
Serial |
2106 |
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Permanent link to this record |
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Author |
Smeulders, G.; Meynen, V.; van Baelen, G.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Maes, B.U.W.; Cool, P. |
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Title |
Rapid microwave-assisted synthesis of benzene bridged periodic mesoporous organosilicas |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
|
|
Volume |
19 |
Issue |
19 |
Pages |
3042-3048 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY) |
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Abstract |
Following extended use in organic chemistry, microwave-assisted synthesis is gaining more importance in the field of inorganic chemistry, especially for the synthesis of nanoporous materials. It offers some major advantages such as a significant shortening of the synthesis time and an improved promotion of nucleation. In the research here reported, microwave technology is applied for the synthesis of benzene bridged PMOs (periodic mesoporous organosilicas). PMOs are one of the latest innovations in the field of hybrid ordered mesoporous materials and have attracted much attention because of their feasibility in electronics, catalysis, separation and sorption applications. The different synthesis steps (stirring, aging and extraction) of the classical PMO synthesis are replaced by microwave-assisted synthesis steps. The characteristics of the as-synthesized materials are evaluated by X-ray diffraction, N2-sorption, thermogravimetric analysis, scanning- and transmission electron microscopy. The microwave-assisted synthesis drastically reduces the synthesis time by more than 40 hours without any loss in structural properties, such as mesoscale and molecular ordering. The porosity of the PMO materials has even been improved by more than 25%. Moreover, the number of handling/transfer steps and amounts of chemicals and waste are drastically reduced. The study also shows that there is a clear time (1 to 3 hours) and temperature frame (373 K to 403 K) wherein synthesis of benzene bridged PMO is optimal. In conclusion, the microwave-assisted synthesis pathway allows an improved material to be obtained in a more economical way i.e. a much shorter time with fewer chemicals and less waste. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000265919300024 |
Publication Date |
2009-03-17 |
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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 |
0959-9428;1364-5501; |
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 |
20 |
Open Access |
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Notes |
Fwo; Iwt |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:76844 |
Serial |
2810 |
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Permanent link to this record |
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Author |
Van Tendeloo, G.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V. |
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Title |
Advanced electron microscopy and its possibilities to solve complex structures: application to transition metal oxides |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
19 |
Issue |
18 |
Pages |
2660-2670 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Design and optimization of materials properties can only be performed through a thorough knowledge of the structure of the compound. In this feature article we illustrate the possibilities of advanced electron microscopy in materials science and solid state chemistry. The different techniques are briefly discussed and several examples are given where the structures of complex oxides, often with a modulated structure, have been solved using electron microscopy. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000265740600002 |
Publication Date |
2009-02-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
9 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:77065 |
Serial |
68 |
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Permanent link to this record |
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Author |
Esken, D.; Zhang, X.; Lebedev, O.I.; Schröder, F.; Fischer, R.A. |
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Title |
Pd@MOF-5: limitations of gas-phase infiltration and solution impregnation of [Zn4O(bdc)3] (MOF-5) with metalorganic palladium precursors for loading with Pd nanoparticles |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
19 |
Issue |
9 |
Pages |
1314-1319 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The limitations of the loading of the porous metalorganic framework [Zn4O(bdc)3] (bdc = benzene-1,4-dicarboxylate; MOF-5 or IRMOF-1) with Pd nanoparticles was investigated. First, the volatile organometallic precursor [Pd(5-C5H5)(3-C3H5)] was employed to get the inclusion compound [Pd(5-C5H5)(3-C3H5)]x@MOF-5 via gas-phase infiltration at 10-3 mbar. A loading of four molecules of [Pd(5-C5H5)(3-C3H5)] per formula unit of MOF-5 (x = 4) can be reached (35 wt.% Pd). Second, the metalorganic precursor [Pd(acac)2] (acac = 2,4-pentanedionate) was used and the inclusion materials [Pd(acac)2]x@MOF-5 of different Pd loadings were obtained by incipient wetness infiltration. However, the maximum loading was lower as compared with the former case with about two precursor molecules per formula unit of MOF-5. Both loading routes are suitable for the synthesis of Pd nanoparticles inside the porous host matrix. Homogeneously distributed nanoparticles with diameter of 2.4(±0.2) nm can be achieved by photolysis of the inclusion compounds [Pd(5-C5H5)(3-C3H5)]x@MOF-5 (x 4), while the hydrogenolysis of [Pd(acac)2]x@MOF-5 (x 2) leads to a mixture of small particles inside the network (< 3 nm) and large Pd agglomerates (40 nm) on the outer surface of the MOF-5 specimens. The pure Pdx@MOF-5 materials proved to be stable under hydrogen pressure (2 bar) at 150 °C over many hours. Neither hydrogenation of the bdc linkers nor particle growth was observed. The new composite materials were characterized by 1H/13C-MAS-NMR, powder XRD, ICP-AES, FT-IR, N2 sorption measurements and high resolution TEM. Raising the Pd loading of a representative sample Pd4@MOF-5 (35 wt.% Pd) by using [Pd(5-C5H5)(3-C3H5)] as precursor in a second cycle of gas-phase infiltration and photolysis was accompanied by the collapse of the long-range crystalline order of the MOF. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000263450300015 |
Publication Date |
2009-01-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
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ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
100 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:76318 |
Serial |
2565 |
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Permanent link to this record |
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Author |
Horemans, B.; Krata, A.; Buczyńska, A.J.; Dirtu, A.C.; van Meel, K.; Van Grieken, R.; Bencs, L. |
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Title |
Major ionic species in size-segregated aerosols and associated gaseous pollutants at a coastal site on the Belgian North Sea |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of environmental monitoring |
Abbreviated Journal |
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Volume |
11 |
Issue |
3 |
Pages |
670-677 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The chemical composition of airborne particulate matter (PM) was studied at a coastal region near De Haan, Belgium, during a winterspring and a summer campaign in 2006. The major ionic components of size-segregated PM, i.e. NH4+, Na+, K+, Mg2+, Ca2+, Cl-, NO3-, and SO42-, and related gaseous pollutants (SO2, NO2, NH3, HNO2, and HNO3) were monitored on a daily basis. Air mass backward-trajectories aided in evaluating the origin of the diurnal pollution load. This was characterised with high levels of fine secondary inorganic aerosols (NH4+, NO3-, and non-sea-salt SO42-) for continental air masses, and sea-salts as the dominant species in coarse maritime aerosols. Seasonal variations in the level of major ionic species were explained by weather conditions and the release of dimethyl sulfide from marine regions. This species was responsible for an increased sea-salt Cl- depletion during summer (56%), causing elevated levels of HCl. Neutralisation ratios for the coarse fraction (0.60.8) suggested a depleted NH4+ level, while that for the fine fraction (1.11.3) had definitely an excess of NH4+, formed by the neutralisation of HCl. The results of factor analysis and the extent of SO2 oxidation indicated that the major ionic species originated from both local and remote sources, classifying the Belgian coastal region as a combined sourcereceptor area of air 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 |
000264098400022 |
Publication Date |
2008-12-24 |
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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 |
1464-0325; 1464-0333 |
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 |
|
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:74341 |
Serial |
8196 |
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Permanent link to this record |
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Author |
Tirry, W.; Schryvers, D. |
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Title |
Linking a completely three-dimensional nanostrain to a structural transformation eigenstrain |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
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Volume |
8 |
Issue |
9 |
Pages |
752-757 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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. |
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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 |
000269215500022 |
Publication Date |
2009-06-21 |
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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 |
1476-1122;1476-4660; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
39.737 |
Times cited |
53 |
Open Access |
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Notes |
Multimat |
Approved |
Most recent IF: 39.737; 2009 IF: 29.504 |
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Call Number |
UA @ lucian @ c:irua:77657 |
Serial |
1822 |
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Permanent link to this record |
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Author |
Bervoets, A.R.J.; Behets, G.J.; Schryvers, D.; Roels, F.; Yang, Z.; Verberckmoes, S.C.; Damment, S.J.P.; Dauwe, S.; Mubiana, V.K.; Blust, R.; de Broe, M.E.; d' Haese, P.C. |
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Title |
Hepatocellular transport and gastrointestinal absorption of lanthanum in chronic renal failure |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Kidney international |
Abbreviated Journal |
Kidney Int |
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Volume |
75 |
Issue |
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Pages |
389-398 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Pathophysiology |
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Abstract |
Lanthanum carbonate is a new phosphate binder that is poorly absorbed from the gastrointestinal tract and eliminated largely by the liver. After oral treatment, we and others had noticed 23 fold higher lanthanum levels in the livers of rats with chronic renal failure compared to rats with normal renal function. Here we studied the kinetics and tissue distribution, absorption, and subcellular localization of lanthanum in the liver using transmission electron microscopy, electron energy loss spectrometry, and X-ray fluoresence. We found that in the liver lanthanum was located in lysosomes and in the biliary canal but not in any other cellular organelles. This suggests that lanthanum is transported and eliminated by the liver via a transcellular, endosomal-lysosomal-biliary canicular transport route. Feeding rats with chronic renal failure orally with lanthanum resulted in a doubling of the liver levels compared to rats with normal renal function, but the serum levels were similar in both animal groups. These levels plateaued after 6 weeks at a concentration below 3 g/g in both groups. When lanthanum was administered intravenously, thereby bypassing the gastrointestinal tract-portal vein pathway, no difference in liver levels was found between rats with and without renal failure. This suggests that there is an increased gastrointestinal permeability or absorption of oral lanthanum in uremia. Lanthanum levels in the brain and heart fluctuated near its detection limit with long-term treatment (20 weeks) having no effect on organ weight, liver enzyme activities, or liver histology. We suggest that the kinetics of lanthanum in the liver are consistent with a transcellular transport pathway, with higher levels in the liver of uremic rats due to higher intestinal absorption. |
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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 |
000263145800009 |
Publication Date |
2008-12-03 |
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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 |
0085-2538;1523-1755; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.395 |
Times cited |
29 |
Open Access |
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Notes |
Fwo; Iwt |
Approved |
Most recent IF: 8.395; 2009 IF: 6.193 |
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Call Number |
UA @ lucian @ c:irua:72290 |
Serial |
1417 |
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Permanent link to this record |
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Author |
Tambuyzer, B.R.; Bergwerf, I.; de Vocht, N.; Reekmans, K.; Daans, J.; Jorens, P.G.; Goossens, H.; Ysebaert, D.K.; Chatterjee, S.; Van Marck, E.; Berneman, Z.N.; Ponsaerts, P. |
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Title |
Allogeneic stromal cell implantation in brain tissue leads to robust microglial activation |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Immunology and cell biology |
Abbreviated Journal |
Immunol Cell Biol |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP); Bio-Imaging lab; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Although adult and embryonic stem cell-based therapy for central nervous system (CNS) injury is being developed worldwide, less attention is given to the immunological aspects of allogeneic cell implantation in the CNS. The latter is of major importance because, from a practical point of view, future stem cell-based therapy for CNS injury will likely be performed using well-characterised allogeneic stem cell populations. In this study, we aimed to further describe the immunological mechanism leading to rejection of allogeneic bone marrow-derived stromal cells (BM-SC) after implantation in murine CNS. For this, we first investigated the impact of autologous and allogeneic BM-SC on microglia activation in vitro. Although the results indicate that both autologous and allogeneic BM-SC do not activate microglia themselves in vitro, they also do not inhibit activation of microglia after exogenous stimuli in vitro. Next, we investigated the impact of allogeneic BM-SC on microglia activation in vivo. In contrast to the in vitro observations, microglia become highly activated in vivo after implantation of allogeneic BM-SC in the CNS of immune-competent mice. Moreover, our results suggest that microglia, rather than T-cells, are the major contributors to allograft rejection in the CNS. |
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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 |
Adelaide |
Editor |
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Language |
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Wos |
000266208800003 |
Publication Date |
2009-03-17 |
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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 |
0818-9641 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.557 |
Times cited |
31 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.557; 2009 IF: 4.200 |
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Call Number |
UA @ lucian @ c:irua:74903 |
Serial |
4515 |
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Permanent link to this record |
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Author |
Zarenia, M.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. |
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Title |
Electrostatically confined quantum rings in bilayer graphene |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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Volume |
9 |
Issue |
12 |
Pages |
4088-4092 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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. |
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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 |
000272395400023 |
Publication Date |
2009-08-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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 |
42 |
Open Access |
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Notes |
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Approved |
Most recent IF: 12.712; 2009 IF: 9.991 |
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Call Number |
UA @ lucian @ c:irua:80318 |
Serial |
1024 |
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Permanent link to this record |