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Records |
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Author |
Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Superconducting nanofilms : molecule-like pairing induced by quantum confinement |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
18 |
Pages |
185701-185701,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs. |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
London |
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Wos |
000303500900018 |
Publication Date |
2012-04-05 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
26 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:98223 |
Serial |
3357 |
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Permanent link to this record |
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Author |
Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Thermomechanical properties of graphene : valence force field model approach |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
17 |
Pages |
175303-175303,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64. |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
London |
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Wos |
000303499700012 |
Publication Date |
2012-04-05 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
29 |
Open Access |
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Notes |
; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:99123 |
Serial |
3639 |
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Permanent link to this record |
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Author |
Wang, H.; Cuppens, J.; Biermans, E.; Bals, S.; Fernandez-Ballester, L.; Kvashnina, K.O.; Bras, W.; van Bael, M.J.; Temst, K.; Vantomme, A. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Tuning of the size and the lattice parameter of ion-beam synthesized Pb nanoparticles embedded in Si |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
45 |
Issue |
3 |
Pages |
035301-035301,7 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The size and lattice constant evolution of Pb nanoparticles (NPs) synthesized by high fluence implantation in crystalline Si have been studied with a variety of experimental techniques. Results obtained from small-angle x-ray scattering showed that the Pb NPs grow with increasing implantation fluence and annealing duration. The theory of NP growth kinetics can be applied to qualitatively explain the size evolution of the Pb NPs during the implantation and annealing processes. Moreover, the lattice constant of the Pb NPs was evaluated by conventional x-ray diffraction. The lattice dilatation was observed to decrease with increasing size of the Pb NPs. Such lattice constant tuning can be attributed to the pseudomorphism caused by the lattice mismatch between the Pb NPs and the Si matrix. |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
London |
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Wos |
000299308400008 |
Publication Date |
2011-12-23 |
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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 |
5 |
Open Access |
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Notes |
Fwo; Iap |
Approved |
Most recent IF: 2.588; 2012 IF: 2.528 |
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Call Number |
UA @ lucian @ c:irua:94208 |
Serial |
3754 |
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Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Ultra-small metallic grains : effect of statistical fluctuations of the chemical potential on superconducting correlations and vice versa |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
27 |
Pages |
275701 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Superconducting correlations in an isolated metallic grain are governed by the interplay between two energy scales: the mean level spacing delta and the bulk pairing gap Delta(0), which are strongly influenced by the position of the chemical potential with respect to the closest single-electron level. In turn superconducting correlations affect the position of the chemical potential. Within the parity projected BCS model we investigate the probability distribution of the chemical potential in a superconducting grain with randomly distributed single-electron levels. Taking into account statistical fluctuations of the chemical potential due to the pairing interaction, we find that such fluctuations have a significant impact on the critical level spacing delta(c) at which the superconducting correlations cease: the critical ratio delta(c)/Delta(0) at which superconductivity disappears is found to be increased. |
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Corporate Author |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
London |
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Language |
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Wos |
000305653100012 |
Publication Date |
2012-06-21 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
9 |
Open Access |
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Notes |
; This work was supported by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF network INSTANS. MDC and AAS are grateful to A Vagov for stimulating discussions. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:100280 |
Serial |
3793 |
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Permanent link to this record |
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Author |
Marikutsa, A.; Krivetskiy, V.; Yashina, L.; Rumyantseva, M.; Konstantinova, E.; Ponzoni, A.; Comini, E.; Abakumov, A.; Gaskov, A. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Catalytic impact of RuOx clusters to high ammonia sensitivity of tin dioxide |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Sensors and actuators : B : chemical
T2 – 25th Eurosensors Conference, SEP 04-07, 2011, Athens, GREECE |
Abbreviated Journal |
Sensor Actuat B-Chem |
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Volume |
175 |
Issue |
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Pages |
186-193 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A comparative study of NH3-sensing performance of blank and modified nanocrystal line SnO2 was performed. Tin dioxide modified by ruthenium displayed the highest ammonia sensitivity with a maximum signal at 200 degrees C. The modifier was shown by XPS and EPR to occur in a mixed valence state of oxidized ruthenium distributed between the surface and bulk of tin dioxide nanocrystals. RuOx clustering on SnO2 surface was detected by means of electron microscopy assisted EDX-mapping. The effect of RuOx on tin dioxide interaction with ammonia was studied by temperature-programmed NH3 desorption, simultaneous Kelvin probe and DC-resistance measurements, EPR spectroscopy and analyses of the gas-solid interaction products. The modifier was shown to promote the materials reactivity to NH3 due to the catalytic activity of RuOx. The interaction with ammonia resulted in dipoles formation on the oxide surface along with reducing the grains net surface charge, established from the electron affinity increase and resistance decrease during NH3 exposure. The RuOx-catalyzed gas-solid interaction was deduced to proceed deeper than in the case of non-modified SnO2 and to yield nitrogen oxides (e.g. NO2), as was suggested by the oxidative character of gaseous products of NH3 interaction with RuOx-modified tin dioxide at 200 degrees C. (C) 2012 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lausanne |
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Language |
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Wos |
000312358700033 |
Publication Date |
2012-06-19 |
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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 |
0925-4005; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.401 |
Times cited |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 5.401; 2012 IF: 3.535 |
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Call Number |
UA @ lucian @ c:irua:105985 |
Serial |
293 |
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Permanent link to this record |
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Author |
Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Gold clusters on WO3 nanoneedles grown via AACVD : XPS and TEM studies |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Materials chemistry and physics |
Abbreviated Journal |
Mater Chem Phys |
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Volume |
134 |
Issue |
2/3 |
Pages |
809-813 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties. |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lausanne |
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Language |
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Wos |
000305918200038 |
Publication Date |
2012-04-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0254-0584; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.084 |
Times cited |
52 |
Open Access |
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Notes |
Iap |
Approved |
Most recent IF: 2.084; 2012 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:97705 |
Serial |
1356 |
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Permanent link to this record |
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Author |
Bouvier, S.; Benmhenni, N.; Tirry, W.; Gregory, F.; Nixon, M.E.; Cazacu, O.; Rabet, L. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Hardening in relation with microstructure evolution of high purity \alpha-titanium deformed under monotonic and cyclic simple shear loadings at room temperature |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
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Volume |
535 |
Issue |
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Pages |
12-21 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The aim of this paper is to gain understanding of the quasi-static, large strain deformation behavior at room-temperature of high-purity alpha-Ti with an initial split-basal texture. Simple shear tests were conducted along different directions in order to quantify the material's anisotropy and hardening evolution for different strain paths such as monotonic, Bauschinger, and cyclic loadings. The stress-strain curves indicate that the material displays strong anisotropy in the flow behavior. In order to capture the link between microstructure evolution (occurrence of twinning, grain size evolution, etc.) and the macroscopic response, a thoroughly detailed multi-scale characterization using scanning electron microscope (SEM) observations and electron backscattered diffraction (EBSD) analysis was also conducted. Specifically, EBSD analyses indicate that the twin activity and grain fragmentation are responsible for the observed difference between the macroscopic hardening rates corresponding to different directions and loading paths. (C) 2011 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lausanne |
Editor |
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Language |
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Wos |
000301402400003 |
Publication Date |
2011-12-17 |
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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 |
0921-5093; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.094 |
Times cited |
22 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.094; 2012 IF: 2.108 |
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Call Number |
UA @ lucian @ c:irua:97824 |
Serial |
1410 |
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Permanent link to this record |
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Author |
Coghe, F.; Tirry, W.; Rabet, L.; Schryvers, D.; Van Houtte, P. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Importance of twinning in static and dynamic compression of a Ti-6Al-4V titanium alloy with an equiaxed microstructure |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Materials science and engineering: part A: structural materials: properties, microstructure and processing |
Abbreviated Journal |
Mat Sci Eng A-Struct |
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Volume |
537 |
Issue |
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Pages |
1-10 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Whereas deformation twinning is known to be an important deformation mechanism for hexagonal materials like magnesium and pure titanium, so far almost no literature exists on the twinning behaviour of the Ti-6Al-4V alloy. In this work it was shown that the activation of twinning as a deformation mechanism could have a pronounced effect on the mechanical behaviour of the Ti-6Al-4V alloy. This effect is even more pronounced under dynamic loading conditions. Transmission electron microscopy showed that only the {1 0 1 2}{1 0 1 1} tensile twin system was activated under certain loading conditions. Light-optical microscopy and electron backscatter diffraction data were afterwards used to experimentally determine the twin fractions. The importance of twinning for the texture evolution was also studied. It was shown that even small twin fractions can lead to distinct texture features, especially due to the discrete reorientation of the c-axes. The experimental results were compared to simulated results that were obtained with a viscoplastic self-consistent crystal plasticity code, after experimental validation that twinning can be reliably modelled as a unidirectional slip system. Although good agreement was obtained for the experimental and simulated stress-strain curves, the simulated results concerning twinning correlated well only on a qualitative basis as the simulated twin fractions were systematically higher than the experimental fractions. This seems to strengthen the hypothesis made by other research groups that complete grains might reorient by twinning. (C) 2011 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lausanne |
Editor |
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Language |
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Wos |
000301473300001 |
Publication Date |
2011-12-21 |
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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 |
0921-5093; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.094 |
Times cited |
35 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.094; 2012 IF: 2.108 |
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Call Number |
UA @ lucian @ c:irua:97818 |
Serial |
1565 |
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Permanent link to this record |
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Author |
Tytgat, T.; Hauchecorne, B.; Abakumov, A.M.; Smits, M.; Verbruggen, S.W.; Lenaerts, S. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Photocatalytic process optimisation for ethylene oxidation |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
209 |
Issue |
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Pages |
494-500 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
When studying photocatalysis it is important to consider, beside the chemical approach, the engineering part related to process optimisation. To achieve this a fixed bed photocatalytic set-up consisting of different catalyst placings, in order to vary catalyst distribution, is studied. The use of a fixed quantity of catalyst placed packed or randomly distributed in the reactor, results in an almost double degradation for the distributed catalyst. Applying this knowledge leads to an improved performance with limited use of catalyst. A reactor only half filled with catalyst leads to higher degradation performance compared to a completely filled reactor. Taking into account this simple process optimisation by better distributing the catalyst a more sustainable photocatalytic air purification process is achieved. (C) 2012 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lausanne |
Editor |
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Language |
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Wos |
000311190500058 |
Publication Date |
2012-08-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1385-8947; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
12 |
Open Access |
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Notes |
; We are grateful for the delivered photocatalyst by Evonik as well as for the PhD grant (T. Tytgat) given by the Institute of Innovation by Science and Technology in Flanders (IWT). ; |
Approved |
Most recent IF: 6.216; 2012 IF: 3.473 |
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Call Number |
UA @ lucian @ c:irua:105185 |
Serial |
2609 |
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Permanent link to this record |
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Author |
Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Cyclotron resonance of trilayer graphene |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
86 |
Issue |
8 |
Pages |
085412 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The cyclotron resonance energies, the corresponding oscillator strengths, and the cyclotron absorption spectrum for trilayer graphene are calculated for both ABA and ABC stacking. A gate potential across the stacked layers leads to (1) a reduction of the transition energies, (2) a lifting of the degeneracy of the zero Landau level, and (3) the removal of the electron-hole symmetry. |
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Corporate Author |
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Publisher |
|
Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lancaster, Pa |
Editor |
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|
Language |
|
Wos |
000307273100009 |
Publication Date |
2012-08-08 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
; This work was supported by the National Council for the Improvement of Higher education (CAPES), the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-V1), the bilateral projects between Flanders and Brazil and the CNPq and FWO-V1, and the ESF-Eurographene project CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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|
Call Number |
UA @ lucian @ c:irua:100815 |
Serial |
604 |
|
Permanent link to this record |
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|
|
Author |
Neek-Amal, M.; Covaci, L.; Peeters, F.M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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|
Title |
Nanoengineered nonuniform strain in graphene using nanopillars |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
86 |
Issue |
4 |
Pages |
041405 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Recent experiments showed that nonuniform strain can be produced by depositing graphene over pillars. We employed atomistic calculations to study the nonuniform strain and the induced pseudomagnetic field in graphene on top of nanopillars. By decreasing the distance between the nanopillars a complex distribution for the pseudomagnetic field can be generated. Furthermore, we performed tight-binding calculations of the local density of states (LDOS) by using the relaxed graphene configuration obtained from atomistic calculations. We find that the quasiparticle LDOS are strongly modified near the pillars, both at low energies showing sublattice polarization and at high energies showing shifts of the van Hove singularity. Our study shows that changing the specific pattern of the nanopillars allows us to create a desired shape of the pseudomagnetic field profile while the LDOS maps provide an input for experimental verification by scanning tunneling 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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lancaster, Pa |
Editor |
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Language |
|
Wos |
000306313900001 |
Publication Date |
2012-07-14 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
51 |
Open Access |
|
|
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-V1) and the EuroGRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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|
Call Number |
UA @ lucian @ c:irua:100765 |
Serial |
2255 |
|
Permanent link to this record |
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Author |
Bousige, C.; Rols, S.; Paineau, E.; Rouziere, S.; Mocuta, C.; Verberck, B.; Wright, J.P.; Kataura, H.; Launois, P. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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|
Title |
Progressive melting in confined one-dimensional C60 chains |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
86 |
Issue |
4 |
Pages |
045446 |
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|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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|
Abstract |
C-60 fullerenes confined inside single-walled carbon nanotubes form an archetypal one-dimensional system. X-ray diffraction experiments, from room temperature to 1073 K, reveal an increasing melting phenomenon. Detailed analysis of the sawtooth peak characteristic of the fullerene organization allows the quantitative determination of fluctuations in intermolecular distances. The present results validate the predictions of one-dimensional statistical models. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lancaster, Pa |
Editor |
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Language |
|
Wos |
000306925300007 |
Publication Date |
2012-08-01 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
|
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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|
Call Number |
UA @ lucian @ c:irua:100835 |
Serial |
2726 |
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Permanent link to this record |
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Author |
Matulis, A.; Masir, M.R.; Peeters, F.M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Scattering of a Dirac electron on a mass barrier |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
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|
Volume |
86 |
Issue |
2 |
Pages |
022101 |
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|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The interaction of a wave packet (and in particular the wave front) with a mass barrier is investigated in one dimension. We discuss the main features of the wave packet that are inherent to two-dimensional wave packets, such as compression during reflection, penetration in the case when the energy is lower than the height of the barrier, waving tails, precursors, and the retardation of the reflected and penetrated wave packets. These features depend on the wave-packet envelope function which we demonstrate by considering the case of a rectangular wave packet with sharp front and trailing edges and a smooth Gaussian wave packet. The method of Fourier integral for obtaining the nonstationary solutions is used. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000306991200001 |
Publication Date |
2012-08-01 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.925 |
Times cited |
9 |
Open Access |
|
|
|
Notes |
; This research was supported by the Flemish Science Foundation (FWO-Vl) and (in part) by the Lithuanian Science Council under Project No. MIP-79/2010. ; |
Approved |
Most recent IF: 2.925; 2012 IF: 3.042 |
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Call Number |
UA @ lucian @ c:irua:100822 |
Serial |
2948 |
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Permanent link to this record |
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Author |
Pina, J.C.; de Souza Silva, C.C.; Milošević, M.V. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Stability of fractional vortex states in a two-band mesoscopic superconductor |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
86 |
Issue |
2 |
Pages |
024512 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the stability of noncomposite fractional vortex states in a mesoscopic two-band superconductor within the two-component Ginzburg-Landau model. Our analysis explicitly takes into account the relationship between the model parameters and microscopic material parameters, such as partial density of states, Fermi velocities and elements of the electron-phonon coupling matrix. We have found that states with different phase winding number in each band (L-1 not equal L-2) and fractional flux can exist in many different configurations, including rather unconventional ones where the dominating band carries larger winding number and states where vertical bar L-1 – L-2 vertical bar > 1. We present a detailed analysis of the stability of the observed vortex structures with respect to changing the microscopic parameters, showing that, in the weak coupling case, fractional vortex states can be assessed in essentially the whole range of temperatures and applied magnetic fields in which both bands are active. Finally, we propose an efficient way of increasing the range of parameters for which these fractional vortex states can be stabilized. In particular, our proposal allows for observation of fractional vortex structures in materials with stronger coupling, where those states are forbidden at a homogeneous field. This is accomplished with the help of the stray fields of a suitably prepared magnetic dot placed nearby the superconducting disk. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000306309600006 |
Publication Date |
2012-07-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
|
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|
Notes |
; We thank Eric B. Claude, Miguel A. Zorro, and Rogerio M. da Silva for assistance in the development of the numerical code used in our simulations. This work was supported by the Brazilian science agencies CNPq and FACEPE, by the FACEPE/CNPq-PRONEX program, under Grant No. APQ-0589-1.05/08, and by CNPq-FWO Brazil-Flanders co-operation program. M.V.M. acknowledges support from the CAPES-PVE program. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:100766 |
Serial |
3126 |
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Permanent link to this record |
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Author |
Costamagna, S.; Neek-Amal, M.; Los, J.H.; Peeters, F.M. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Thermal rippling behavior of graphane |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
86 |
Issue |
4 |
Pages |
041408-4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Thermal fluctuations of single layer hydrogenated graphene (graphane) are investigated using large scale atomistic simulations. By analyzing the mean square value of the height fluctuations < h(2)> and the height-height correlation function H(q) for different system sizes and temperatures, we show that hydrogenated graphene is an unrippled system in contrast to graphene. The height fluctuations are bounded, which is confirmed by a H(q) tending to a constant in the long wavelength limit instead of showing the characteristic scaling law q(4-eta)(eta similar or equal to 0.85) predicted by membrane theory. This unexpected behavior persists up to temperatures of at least 900 K and is a consequence of the fact that in graphane the thermal energy can be accommodated by in-plane bending modes, i.e., modes involving C-C-C bond angles in the buckled carbon layer, instead of leading to significant out-of-plane fluctuations that occur in graphene. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000306649200002 |
Publication Date |
2012-07-23 |
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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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
46 |
Open Access |
|
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|
Notes |
; We thank A. Fasolino, A. Dobry, and K. H. Michel for their useful comments. S.C. is supported by the Belgian Science Foundation (BELSPO). This work is supported by the ESF-EuroGRAPHENE project CONGRAN and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:100840 |
Serial |
3630 |
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Permanent link to this record |
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Author |
Nagy, N.V.; Van Doorslaer, S.; Szabó-Plánka, T.; Van Rompaey, S.; Hamza, A.; Fülöp, F.; Tóth, G.K.; Rockenbauer, A. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
|
|
Title |
Copper(II)-binding ability of stereoisomeric cis- and trans-2-aminocyclohexanecarboxylic acidl-phenylalanine dipeptides : a combined CW/pulsed EPR and DFT study |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
|
|
Volume |
51 |
Issue |
3 |
Pages |
1386-1399 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
With the aim of an improved understanding of the metal-complexation properties of alicyclic β-amino acid stereoisomers, and their peptides, the complex equilibria and modes of coordination with copper(II) of l-phenylalanine (F) derivatives of cis/trans-2-aminocyclohexanecarboxylic acid (c/tACHC), i.e. the dipeptides F-c/tACHC and c/tACHC-F, were investigated by a combination of CW and pulsed EPR methods. For the interpretation of the experimental data, DFT quantum-chemical calculations were carried out. Simulation of a pH-dependent series of room-temperature CW-EPR spectra revealed the presence of EPR-active complexes ([Cu(aqua)]2+, [CuL]+, [CuLH1], [CuLH2]−, and [CuL2H1]−), and an EPR-inactive species ([Cu2L2H3]−) in aqueous solutions for all studied cases. [CuLH]2+ was included in the equilibrium model for the c/tACHC-Fcopper(II) systems, and [CuL2], together with two coordination isomers of [CuL2H1]−, were also identified in the F-tACHCcopper(II) system. Comparison of the complexation properties of the diastereomeric ligand pair F-(1S,2R)-ACHC and F-(1R,2S)-ACHC did not reveal significant differences. Considerably lower formation constants were obtained for the trans than for the cis isomers for both the F-c/tACHC and the c/tACHC-F pairs in the case of [CuLH1] involving tridentate coordination by the amino, the deprotonated peptide, and the carboxylate groups. A detailed structural analysis by pulsed EPR methods and DFT calculations indicated that there was no significant destabilization for the complexes of the trans isomers. The lower stability of their complexes was explained by the limitation that only the conformer with donor groups in equatorialequatorial ring positions can bind to copper(II), whereas both equatorial-axial conformers of the cis isomers are capable of binding. From a consideration of the proton couplings obtained with X-band 1H HYSCORE, 2H exchange experiments, and DFT, the thermodynamically most stable cyclohexane ring conformer was assigned for all four [CuLH1] complexes. For the F-cACHC case, the conformer did not match the most stable conformer of the free ligand. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000300474700029 |
Publication Date |
2012-01-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.857 |
Times cited |
18 |
Open Access |
|
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|
Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:96729 |
Serial |
515 |
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Permanent link to this record |
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Author |
Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Rozova, M.G.; Sarakinou, E.; Antipov, E.V. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Expanding the Ruddlesden-Popper manganite family : the n=3 La3.2Ba0.8Mn3O10 Member |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
21 |
Pages |
11487-11492 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
La3.2Ba0.8Mn3O10, a representative of the rare n = 3 members of the Ruddlesden-Popper manganites A(n+1)Mn(n)O(3n+1), was synthesized in an evacuated sealed silica tube. Its crystal structure was refined from a combination of powder X-ray diffraction (PXD) and precession electron diffraction (PED) data, with the rotations of the MnO6 octahedra described within the symmetry-adapted mode approach (space group Cccm, a = 29.068(1) angstrom, b = 5.5504(5) angstrom, c = 5.5412(5) angstrom; PXD RF = 0.053, RP = 0.026; PED RF = 0.248). The perovskite block in La3.2Ba0.8Mn3O10 features an octahedral tilting distortion with out-of-phase rotations of the Mn06 octahedra according to the (Phi,Phi,0)(Phi,Phi,0) mode, observed for the first time in the n = 3 Ruddlesden-Popper structures. The Mn06 octahedra demonstrate a noticeable deformation with the elongation of two apical Mn-O bonds due to the Jahn-Teller effect in the Mn3+ cations. The relationships between the octahedral tilting distortion, the ionic radii of the cations at the A- and B-positions, and the mismatch between the perovslcite and rock-salt blocks of the Ruddlesden-Popper structure are discussed. At low temperatures, La3.2Ba0.8Mn3O10 reveals a sizable remnant magnetization of about 1.3 mu(B)/Mn at 2K, and shows signatures of spin freezing below 150 K. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000313220200036 |
Publication Date |
2012-10-17 |
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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 |
|
Series Issue |
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Edition |
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ISSN |
0020-1669;1520-510X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
2 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:110121 |
Serial |
1133 |
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Permanent link to this record |
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Author |
Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Hadermann, J.; Hodges, J.P.; Herber, R.H.; Nowik, I.; Greenblatt, M.; |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Magnetic and structural studies of the multifunctional material SrFe0.75Mo0.25O3-\text{\textgreek{d}} |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
22 |
Pages |
12273-12280 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
SrFe0.75Mo0.25O3-delta has been recently discovered as an extremely efficient electrode for intermediate temperature solid oxide fuel cells (IT-SOFCs). We have performed structural and magnetic studies to fully characterize this multifunctional material. We have observed by powder neutron diffraction (PND) and transmission electron microscopy (TEM) that its crystal symmetry is better explained with a tetragonal symmetry (I4/mcm space group) than with the previously reported orthorhombic symmetry (Pnma space group). The temperature dependent magnetic properties indicate an exceptionally high magnetic ordering temperature (T-N similar to 750 K), well above room temperature. The ordered magnetic structure at low temperature was determined by PND to be an antiferromagnetic coupling of the Fe cations. Mossbauer spectroscopy corroborated the PND results. A detailed study, with X-ray absorption spectroscopy (XAS), in agreement with the Mossbauer results, confirmed the formal oxidation states of the cations to be mixed valence Fe3+/4+ and Mo6+. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000311173700024 |
Publication Date |
2012-10-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0020-1669;1520-510X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.857 |
Times cited |
12 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:105142 |
Serial |
1862 |
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Permanent link to this record |
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Author |
Horemans, B.; Van Holsbeke, C.; Vos, W.; Darchuk, L.; Novakovic, V.; Fontan, A.C.; de Backer, J.; van Grieken, R.; de Backer, W.; De Wael, K. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Particle deposition in airways of chronic respiratory patients exposed to an urban aerosol |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Environmental science and technology |
Abbreviated Journal |
Environ Sci Technol |
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Volume |
46 |
Issue |
21 |
Pages |
12162-12169 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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Abstract |
Urban atmospheres in modern cities carry characteristic mixtures of particulate pollution which are potentially aggravating for chronic respiratory patients (CRP). Although air quality surveys can be detailed, the obtained information is not always useful to evaluate human health effects. This paper presents a novel approach to estimate particle deposition rates in airways of CRP, based on real air pollution data. By combining computational fluid dynamics with physical-chemical characteristics of particulate pollution, deposition rates are estimated for particles of different toxicological relevance, that is, minerals, iron oxides, sea salts, ammonium salts, and carbonaceous particles. Also, it enables some qualitative evaluation of the spatial, temporal, and patient specific effects on the particle dose upon exposure to the urban atmosphere. Results show how heavy traffic conditions increases the deposition of anthropogenic particles in the trachea and lungs of respiratory patients (here, +0.28 and +1.5 μg·h1, respectively). In addition, local and synoptic meteorological conditions were found to have a strong effect on the overall dose. However, the pathology and age of the patient was found to be more crucial, with highest deposition rates for toxic particles in adults with a mild anomaly, followed by mild asthmatic children and adults with severe respiratory dysfunctions (7, 5, and 3 μg·h1, respectively). |
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Corporate Author |
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Publisher |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000310665000082 |
Publication Date |
2012-10-04 |
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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 |
0013-936X;1520-5851; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.198 |
Times cited |
5 |
Open Access |
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|
Notes |
; We are grateful for the financial support of n.v. Vooruitzicht. Furthermore, co-workers at the environmental analysis research group are acknowledged for their help in the fieldwork. ; |
Approved |
Most recent IF: 6.198; 2012 IF: 5.257 |
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Call Number |
UA @ lucian @ c:irua:101411 |
Serial |
2557 |
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Permanent link to this record |
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Author |
Charkin, D.O.; Urmanov, A.V.; Kazakov, S.M.; Batuk, D.; Abakumov, A.M.; Knöner, S.; Gati, E.; Wolf, B.; Lang, M.; Shevelkov, A.V.; Van Tendeloo, G.; Antipov, E.V.; |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Synthesis, crystal structure, transport, and magnetic properties of novel ternary copper phosphides, A2Cu6P5(A = Sr, Eu) and EuCu4P3 |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
|
|
Volume |
51 |
Issue |
16 |
Pages |
8948-8955 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Three new ternary copper phosphides, Sr2Cu6P5, Eu2Cu6P5, and EuCu4P3, have been synthesized from the elements in evacuated silica capsules. Eu2Cu6P5 and Sr2Cu6P5 adopt the Ca2Cu6P5-type structure, while EuCu4P3 is isostructural to BaMg4Si3 and still remains the only representative of this structure type among the ternary Cu pnictides. All three materials show metallic conductivity in the temperature range 2 K <= T <= 290 K, with no indication for superconductivity. For Eu2Cu6P5 and EuCu4P3, long-range magnetic order was observed, governed by 4f local moments on the Eu atoms with predominant ferromagnetic interactions. While Eu2Cu6P5 shows a single ferromagnetic transition at T-C = 34 K, the magnetic behavior of EuCu4P3 is more complex, giving rise to three consecutive magnetic phase transitions at 70, 43, and 18 K. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000307606200042 |
Publication Date |
2012-07-31 |
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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 |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
4.857 |
Times cited |
13 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:102217 |
Serial |
3453 |
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Permanent link to this record |
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Author |
Morozov, V.; Arakcheeva, A.; Redkin, B.; Sinitsyn, V.; Khasanov, S.; Kudrenko, E.; Raskina, M.; Lebedev, O.; Van Tendeloo, G. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Na2/7Gd4/7MoO4 : a modulated scheelite-type structure and conductivity properties |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
9 |
Pages |
5313-5324 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Scheelite-type compounds with the general formula (A1,A2)n[(B1,B2)O4]m (2/3 ≤ n/m ≤ 3/2) are the subject of large interest owing to their stability, relatively simple preparation, and optical properties. The creation of cation vacancies (□) in the scheelite-type framework and the ordering of A cations and vacancies can be a new factor in controlling the scheelite-type structure and properties. For a long time, cation-deficient Nd3+:M2/7Gd4/7□1/7MoO4 (M = Li, Na) compounds were considered as potential lasers with diode pumping. They have a defect scheelite-type 3D structure (space group I41/a) with a random distribution of Li+(Na+), Gd3+, and vacancies in the crystal. A Na2/7Gd4/7MoO4 single crystal with scheelite-type structure has been grown by the Czochralski method. Transmission electron microscopy revealed that Na2/7Gd4/7MoO4 has a (3 + 2)D incommensurately modulated structure. The (3 + 2)D incommensurately modulated scheelite-type cation-deficient structure of Na2/7Gd4/7MoO4 [super space group I4̅ (αβ0,βα0)00] has been solved from single-crystal diffraction data. The solution of the (3 + 2)D incommensurately modulated structure revealed the partially disordered distribution of vacancies and Na and Gd cations. High-temperature conductivity measurements performed along the [100] and [001] orientation of the single crystal revealed that the conductivity of Na2/7Gd4/7MoO4 at T = 973 K equals σ = 1.13 × 105 Ω1 cm1. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000303952900055 |
Publication Date |
2012-04-19 |
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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 |
0020-1669;1520-510X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
37 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:98385 |
Serial |
3547 |
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Permanent link to this record |
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Author |
Chernov, S.V.; Dobrovolsky, Y.A.; Istomin, S.Y.; Antipov, E.V.; Grins, J.; Svensson, G.; Tarakina, N.V.; Abakumov, A.M.; Van Tendeloo, G.; Eriksson, S.G.; Rahman, S.M.H.; |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
_Sr{2}GaScO5, Sr10Ga6Sc4O25, and SrGa0.75Sc0.25O2.5 : a play in the octahedra to tetrahedra ratio in oxygen-deficient perovskites |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
2 |
Pages |
1094-1103 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Three different perovskite-related phases were isolated in the SrGa(1-x)Sc(x)O(2.5) system: Sr(2)GaScO(5), Sr(10)Ga(6)Sc(4)O(25), and SrGa(0.75)Sc(0.25)O(2.5), Sr(2)GaScO(5) (x = 0.5) crystallizes in a brownrnillerite-type structure [space group (S.G.) Icmm, a = 5.91048(5) angstrom, b = 15.1594(1) angstrom, and c = 5.70926(4) angstrom] with complete ordering of Sc(3+) and Ga(3+) over octahedral and tetrahedral positions, respectively. The crystal structure of Sr(10)Ga(6)Sc(4)O(25) (x = 0.4) was determined by the Monte Carlo method and refined using a combination of X-ray, neutron, and electron diffraction data [S.G. I4(1)/a, a = 17.517(1) angstrom, c = 32.830(3) angstrom]. It represents a novel type of ordering of the B cations and oxygen vacancies in perovskites. The crystal structure of Sr(10)Ga(6)Sc(4)O(25) can be described as a stacking of eight perovskite layers along the c axis ...[-(Sc/Ga)O(1.6)-SrO(0.8)-(Sc/Ga)O(1.8)-SrO(0.8)-](2 center dot center dot center dot) Similar to Sr(2)GaScO(5), this structure features a complete ordering of the Sc(3+) and Ga(3+) cations over octahedral and tetrahedral positions, respectively, within each layer. A specific feature of the crystal structure of Sr(10)Ga(6)Sc(4)O(25) is that one-third of the tetrahedra have one vertex not connected with other Sc/Ga cations. Further partial replacement of Sc(3+) by Ga(3+) leads to the formation of the cubic perovskite phase SrGa(0.75)Sc(0.25)O(2.5) (x = 0.25) with a = 3.9817(4) angstrom. This compound incorporates water molecules in the structure forming SrGa(0.75)Sc(0.25)O(2.5)center dot xH(2)O hydrate, which exhibits a proton conductivity of similar to 2.0 x 10(-6) S/cm at 673 K. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000299028800042 |
Publication Date |
2011-12-22 |
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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 |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
14 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:96229 |
Serial |
3559 |
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Permanent link to this record |
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Author |
Ramezanipour, F.; Greedan, J.E.; Siewenie, J.; Donaberger, R.L.; Turner, S.; Botton, G.A. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
A vacancy-disordered, oxygen-deficient perovskite with long-range magnetic ordering : local and average structures and magnetic properties of Sr2Fe1.5Cr0.5O5 |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
51 |
Issue |
4 |
Pages |
2638-2644 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The local and average crystal structures and magnetic properties of the oxygen-deficient perovskite Sr2Fe1.5Cr0.5O5+y were studied using powder X-ray and neutron diffraction, neutron-pair distribution function analysis, and electron energy-loss spectroscopy. This material crystallizes in the cubic Pm3̅m space group, with a = 3.94491(14) Å. The oxygen vacancies are distributed randomly throughout the perovskite-type structure, and the average coordination number of the Fe(Cr) sites is 5. Refinement of the neutron diffraction data indicates y 0.05. This is in discordance with an earlier report on a material with the same nominal composition and cell constant. Electron energy-loss Cr L2,3-edge spectroscopy shows that Cr3+ is present, which is also contrary to previous speculation. Neutron-pair distribution function studies show that a brownmillerite-like model involving ordered vacancies and alternating octahedral and tetrahedral coordination at the metal sites, gives a better description of the local structure out to 5 Å. A remarkable phenomenon determined by neutron diffraction in Sr2Fe1.5Cr0.5O5 is the occurrence of a long-range G-type antiferromagnetic ordering with Tc ≈ 565 K because cubic oxygen-deficient perovskites with B-site disorder usually do not undergo transitions to magnetically ordered states. The observation of long-range antiferromagnetic order and the Tc value are in accordance with previous Mössbauer spectroscopic studies. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Easton, Pa |
Editor |
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Language |
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Wos |
000300466300079 |
Publication Date |
2012-01-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0020-1669;1520-510X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.857 |
Times cited |
12 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 4.857; 2012 IF: 4.593 |
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Call Number |
UA @ lucian @ c:irua:95039 |
Serial |
3828 |
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Permanent link to this record |
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Author |
Renard, K.; Idrissi, H.; Schryvers, D.; Jacques, P.J. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Multiscale characterization of the work hardening mechanisms in Fe-Mn based TWIP steels |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Steel research international |
Abbreviated Journal |
Steel Res Int |
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Volume |
83 |
Issue |
4 |
Pages |
385-390 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
When strained in tension, high-manganese austenitic twinning induced plasticity (TWIP) steels achieve very high strength and elongation before necking. The main hypotheses available in the literature about the origin of their excellent work hardening include deformation twinning and dynamic strain ageing. In order to provide some answers, various experiments at different scales were conducted on FeMnC steels and the Fe28 wt%Mn3.5 wt%Al2.8 wt%Si alloy. At a macroscopic scale, tensile tests were performed on all the studied grades. It was shown that, though the FeMnAlSi based alloy retains very high elongation, the FeMnC steels properties are even more extraordinary. Tensile tests at different strain rates with the help of digital image correlation were also performed on the Fe20 wt%Mn1.2 wt%C steel to study the PLC effect occurring in this type of steel. It is suggested that supplementary hardening could come from reorientation of MnC pairs in the cores of the dislocations. At a microscopic scale, the Fe20 wt%Mn1.2 wt%C TWIP steel and the FeMnAlSi grade were thoroughly investigated by means of in situ TEM analysis. In the FeMnC steel, the formed twins could also lead to a composite effect, since they contain plenty of sessile dislocations. In the FeMnAlSi alloy, mechanical twins are thicker and contain fewer defects, leading to a lower work hardening than the other grade. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Verlag Stahleisen |
Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Düsseldorf |
Editor |
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Language |
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Wos |
000302471600016 |
Publication Date |
2012-02-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1611-3683; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.235 |
Times cited |
12 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.235; 2012 IF: 0.493 |
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Call Number |
UA @ lucian @ c:irua:97391 |
Serial |
2239 |
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Permanent link to this record |
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Author |
De Backer, L.A.; Vos, W.; de Backer, J.; Van Holsbeke, C.; Vinchurkar, S.; de Backer, W. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
The acute effect of budesonide/formoterol in COPD : a multi-slice computed tomography and lung function study |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
European Respiratory Journal |
Abbreviated Journal |
Eur Respir J |
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Volume |
40 |
Issue |
2 |
Pages |
298-305 |
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Keywords |
A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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Abstract |
The Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification of chronic obstructive pulmonary disease (COPD) does not always match with other clinical disease descriptors such as exacerbation frequency and quality of life, indicating that forced expiratory volume in 1 s (FEV1) is not a perfect descriptor of the disease. The aim of this study was to find out whether changes in airway geometry after inhalation of the most commonly used inhalation therapy in severe COPD can more adequately be described with an image-based approach than with spirometry. 10 COPD GOLD stage III patients were assessed in a double-blind crossover study. Airway volumes were analysed using segmentation of multi-slice computed tomography (MSCT) images; airway resistance was determined using computational fluid dynamics (CFD). Distal airway volume significantly increased (p=0.011) in patients 4 h after receiving a budesonide/formoterol combination from 9.6+/-4.67 cm(3) to 10.14+/-4.81 cm(3). Also CFD-determined airway resistance significantly decreased (p=0.047) from 0.051+/-0.021 kPa.s.L-1 to 0.043+/- 0.019 kPa.s.L-1. None of the lung function parameters showed a significant change. Only functional residual capacity (FRC) showed a trend to decline (p=0.056). Only the image-based parameters were able to predict the visit at which the combination product was administered. This study showed that imaging is a sensitive, complementary tool to describe changes in airway structure. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Copenhagen |
Editor |
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Language |
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Wos |
000307291700006 |
Publication Date |
2011-12-20 |
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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 |
0903-1936;1399-3003; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.569 |
Times cited |
37 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 10.569; 2012 IF: 6.355 |
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Call Number |
UA @ lucian @ c:irua:101113 |
Serial |
3568 |
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Permanent link to this record |
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Author |
Bliokh, K.Y.; Schattschneider, P.; Verbeeck, J.; Nori, F. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Electron vortex beams in a magnetic field : a new twist on Landau levels and Aharonov-Bohm states |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
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Volume |
2 |
Issue |
4 |
Pages |
041011-41015 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We examine the propagation of the recently discovered electron vortex beams in a longitudinal magnetic field. We consider both the Aharonov-Bohm configuration with a single flux line and the Landau case of a uniform magnetic field. While stationary Aharonov-Bohm modes represent Bessel beams with flux- and vortex-dependent probability distributions, stationary Landau states manifest themselves as nondiffracting Laguerre-Gaussian beams. Furthermore, the Landau-state beams possess field- and vortex-dependent phases: (i) the Zeeman phase from coupling the quantized angular momentum to the magnetic field and (ii) the Gouy phase, known from optical Laguerre-Gaussian beams. Remarkably, together these phases determine the structure of Landau energy levels. This unified Zeeman-Landau-Gouy phase manifests itself in a nontrivial evolution of images formed by various superpositions of modes. We demonstrate that, depending on the chosen superposition, the image can rotate in a magnetic field with either (i) Larmor, (ii) cyclotron (double-Larmor), or (iii) zero frequency. At the same time, its centroid always follows the classical cyclotron trajectory, in agreement with the Ehrenfest theorem. Interestingly, the nonrotating superpositions reproduce stable multivortex configurations that appear in rotating superfluids. Our results open an avenue for the direct electron-microscopy observation of fundamental properties of free quantum-electron states in magnetic fields. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
College Park, Md |
Editor |
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Language |
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Wos |
000311551100001 |
Publication Date |
2012-11-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2160-3308; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.789 |
Times cited |
130 |
Open Access |
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Notes |
Vortex ECASJO_; |
Approved |
Most recent IF: 12.789; 2012 IF: 6.711 |
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Call Number |
UA @ lucian @ c:irua:105139UA @ admin @ c:irua:105139 |
Serial |
991 |
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Permanent link to this record |
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Author |
Varykhalov, A.; Marchenko, D.; Sanchez-Barriga, J.; Scholz, M.R.; Verberck, B.; Trauzettel, B.; Wehling, T.O.; Carbone, C.; Rader, O. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Intact dirac cones at broken sublattice symmetry : photoemission study of graphene on Ni and Co |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review X |
Abbreviated Journal |
Phys Rev X |
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Volume |
2 |
Issue |
4 |
Pages |
041017-10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The appearance of massless Dirac fermions in graphene requires two equivalent carbon sublattices of trigonal shape. While the generation of an effective mass and a band gap at the Dirac point remains an unresolved problem for freestanding extended graphene, it is well established by breaking translational symmetry by confinement and by breaking sublattice symmetry by interaction with a substrate. One of the strongest sublattice-symmetry-breaking interactions with predicted and measured band gaps ranging from 400 meV to more than 3 eV has been attributed to the interfaces of graphene with Ni and Co, which are also promising spin-filter interfaces. Here, we apply angle-resolved photoemission to epitaxial graphene on Ni (111) and Co(0001) to show the presence of intact Dirac cones 2.8 eV below the Fermi level. Our results challenge the common belief that the breaking of sublattice symmetry by a substrate and the opening of the band gap at the Dirac energy are in a straightforward relation. A simple effective model of a biased bilayer structure composed of graphene and a sublattice-symmetry-broken layer, corroborated by density-functional-theory calculations, demonstrates the general validity of our conclusions. |
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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 ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
College Park, Md |
Editor |
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Language |
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Wos |
000312703200001 |
Publication Date |
2012-12-22 |
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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 |
2160-3308; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.789 |
Times cited |
86 |
Open Access |
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|
Notes |
; A. V. acknowledges helpful discussions with N. Sandler. This work was supported by SPP 1459 of the Deutsche Forschungsgemeinschaft. B. V. acknowledges support from the Research Foundation Flanders (FWO-Vlaanderen). B. T. and T. O. W. would like to thank the KITP at Santa Barbara for hospitality during the completion of this work. ; |
Approved |
Most recent IF: 12.789; 2012 IF: 6.711 |
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Call Number |
UA @ lucian @ c:irua:105964 |
Serial |
1677 |
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Permanent link to this record |
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Author |
van den Broek, W.; Van Aert, S.; van Dyck, D. |
![find record details (via OpenURL) openurl](img/xref.gif)
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Title |
Fully automated measurement of the modulation transfer function of charge-coupled devices above the Nyquist frequency |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
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Volume |
18 |
Issue |
2 |
Pages |
336-342 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
The charge-coupled devices used in electron microscopy are coated with a scintillating crystal that gives rise to a severe modulation transfer function (MTF). Exact knowledge of the MTF is imperative for a good correspondence between image simulation and experiment. We present a practical method to measure the MTF above the Nyquist frequency from the beam blocker's shadow image. The image processing has been fully automated and the program is made public. The method is successfully tested on three cameras with various beam blocker shapes. |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Cambridge, Mass. |
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Language |
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Wos |
000302084700011 |
Publication Date |
2012-02-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1431-9276;1435-8115; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.891 |
Times cited |
15 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 1.891; 2012 IF: 2.495 |
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Call Number |
UA @ lucian @ c:irua:96557 |
Serial |
1297 |
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Permanent link to this record |
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Author |
Narayanan, V.; Lommens, P.; De Buysser, K.; Vanpoucke, D.E.P.; Huehne, R.; Molina, L.; Van Tendeloo, G.; van der Voort, P.; Van Driessche, I. |
![goto web page (via DOI) doi](http://nano.uantwerpen.be/nanorefs/img/doi.gif)
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Title |
Aqueous CSD approach for the growth of novel, lattice-tuned LaxCe1-xO\delta epitaxial layers |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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Volume |
22 |
Issue |
17 |
Pages |
8476-8483 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Lanthanumcerium oxide (LCO) films were deposited on Ni-5%W substrates by chemical solution deposition (CSD) from water-based precursors. LCO films containing different ratios of lanthanum and cerium ions (from CeO2 to La2Ce2O7) were prepared. The composition of the layers was optimized towards the formation of LCO buffer layers, lattice-matched with the superconducting YBa2Cu3Oy layer, useful for the development of coated conductors. Single, crack-free LCO layers with a thickness of up to 140 nm could be obtained in a single deposition step. The crystallinity and microstructure of these lattice-matched LCO layers were studied by X-ray diffraction techniques, RHEED and SEM. We find that only layers with thickness below 100 nm show a crystalline top surface although both thick and thin layers show good biaxial texture in XRD. On the most promising layers, AFM and (S)TEM were performed to further evaluate their morphology. The overall surface roughness varies between 3.9 and 7.5 nm, while the layers appear much more dense than the frequently used La2Zr2O7 (LZO) systems, showing much smaller nanovoids (12 nm) than the latter system. Their effective buffer layer action was studied using XPS. The thin LCO layers supported the growth of superconducting YBCO deposited using PLD methods. |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Cambridge |
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Language |
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Wos |
000302367500044 |
Publication Date |
2012-03-20 |
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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 |
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 |
24 |
Open Access |
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Notes |
Iap |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:96960 |
Serial |
148 |
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Permanent link to this record |
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Author |
Turner, S.; Lu, Y.-G.; Janssens, S.D.; da Pieve, F.; Lamoen, D.; Verbeeck, J.; Haenen, K.; Wagner, P.; Van Tendeloo, G. |
![goto web page url](http://nano.uantwerpen.be/nanorefs/img/www.gif)
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Title |
Local boron environment in B-doped nanocrystalline diamond films |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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Volume |
4 |
Issue |
19 |
Pages |
5960-5964 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Thin films of heavily B-doped nanocrystalline diamond (B:NCD) have been investigated by a combination of high resolution annular dark field scanning transmission electron microscopy and spatially resolved electron energy-loss spectroscopy performed on a state-of-the-art aberration corrected instrument to determine the B concentration, distribution and the local B environment. Concentrations of [similar]1 to 3 at.% of boron are found to be embedded within individual grains. Even though most NCD grains are surrounded by a thin amorphous shell, elemental mapping of the B and C signal shows no preferential embedding of B in these amorphous shells or in grain boundaries between the NCD grains, in contrast with earlier work on more macroscopic superconducting polycrystalline B-doped diamond films. Detailed inspection of the fine structure of the boron K-edge and comparison with density functional theory calculated fine structure energy-loss near-edge structure signatures confirms that the B atoms present in the diamond grains are substitutional atoms embedded tetrahedrally into the diamond lattice. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication ![sorted by Place of Publication field, descending order (down)](img/sort_desc.gif) |
Cambridge |
Editor |
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Language |
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Wos |
000308705900026 |
Publication Date |
2012-08-09 |
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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 |
2040-3364;2040-3372; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.367 |
Times cited |
39 |
Open Access |
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Notes |
FWO G056810N; GOA XANES meets ELNES; 246791 COUNTATOMS; Hercules; 262348 ESMI; Methusalem Nano |
Approved |
Most recent IF: 7.367; 2012 IF: 6.233 |
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Call Number |
UA @ lucian @ c:irua:101227UA @ admin @ c:irua:101227 |
Serial |
1825 |
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Permanent link to this record |