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Records |
Links |
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Author |
Peng, L.; Philippaerts, A.; Ke, X.; van Noyen, J.; de Cleppel, F.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. |
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Title |
Preparation of sulfonated ordered mesoporous carbon and its use for the esterification of fatty acids |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Catalysis today |
Abbreviated Journal |
Catal Today |
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| |
Volume |
150 |
Issue |
1/2 |
Pages |
140-146 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Mesoporous carbon, which can be replicated from mesoporous silica and whose surface is hydrophobic, can be an ideal catalyst for the esterification of fatty acids. Here we report an easy and low cost way to prepare sulfonic acid group-functionalized mesoporous carbon. A sample of calcined mesoporous silica SBA-15 was added to an aqueous sucrose solution followed by drying and calcination at different temperatures. In contrast to existing procedures, the obtained hybrid Si/C material was then first sulfonated in H2SO4, before the final removal of the silica template in order to stabilize the porous structure towards the liquid phase sulfonation treatment. Thus the silicacarbon composites, instead of the mesoporous carbon, were successfully sulfonated to introduce SO3H groups, while keeping the ordered mesoporous structure intact. The influence of carbonization temperature was investigated, suggesting an optimum temperature of 873 K. The SO3H group-functionalized mesoporous carbon, denoted as CMK-3-873-SO3H, was characterized by means of XRD, N2 physisorption, SEM, FT-IR, elemental analysis and TEM. It followed that a uniform mesoporous carbon was obtained with an average pore size of 3.89 nm, a specific surface of 807 m2/g and a SO3H group loading of 0.39 meq/g of dry material. Compared with other solid acid catalysts, the resulting material shows enhanced activity in the acid-catalyzed esterification of oleic acid with methanol, and can be used repeatedly. The increased catalytic performance is attributed to the hydrophobic surface and larger pore size of the new catalyst. It can effectively accommodate long chain fatty acids and reject formed water, making the active sites easily accessible. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000275566700024 |
Publication Date  |
2009-09-04 |
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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 |
0920-5861; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.636 |
Times cited |
132 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.636; 2010 IF: 2.993 |
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Call Number |
UA @ lucian @ c:irua:81739 |
Serial |
2706 |
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Author |
Stroobants, N.; Dehairs, F.; Goeyens, L.; Vanderheijden, N.; Van Grieken, R. |
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Title |
Barite formation in the Southern Ocean water column |
Type |
A1 Journal article |
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Year |
1991 |
Publication |
Marine chemistry |
Abbreviated Journal |
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Volume |
35 |
Issue |
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Pages |
411-421 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Address |
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Corporate Author |
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Place of Publication |
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Wos |
A1991GZ58500031 |
Publication Date |
2009-09-04 |
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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 |
0304-4203; 1872-7581 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:664 |
Serial |
7550 |
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Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
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Title |
Ballistic current in metal-oxide-semiconductor field-effect transistors: the role of device topology |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
106 |
Issue |
5 |
Pages |
053702,1-053702,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this study we investigate the effect of device topology on the ballistic current in n-channel metal-oxide-semiconductor field-effect transistors. Comparison of the nanoscale planar and double-gate devices reveals that, down to a certain thickness of the double gate film, the ballistic current flowing in the double gate device is twice as large compared to its planar counterpart. On the other hand, further thinning of the film beyond this threshold is found to change noticeably the confinement and transport characteristics, which are strongly depending on the film material and the surface orientation. For double gate Ge and Si devices there exists a critical film thickness below which the transverse gate field is no longer effectively screened by the inversion layer electron gas and mutual inversion of the two gates is turned on. In the case of GaAs and other similar IIIV compounds, a decrease in the film thickness may drastically change the occupation of the L-valleys and therefore amend the transport properties. The simulation results show that, in both cases, the ballistic current and the transconductance are considerably enhanced. |
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Corporate Author |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000269850300052 |
Publication Date |
2009-09-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:79744 |
Serial |
214 |
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Author |
Abakumov, A.M.; King, G.; Laurinavichute, V.K.; Rozova, M.G.; Woodward, P.M.; Antipov, E.V. |
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Title |
The crystal structure of \alpha-K3AIF6: elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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Volume |
48 |
Issue |
19 |
Pages |
9336-9344 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The crystal structure of α-K3AlF6 was solved and refined from a combination of powder X-ray and neutron diffraction data (a = 18.8385(3)Å, c = 33.9644(6)Å, S.G. I41/a, Z = 80, RP(X-ray) = 0.037, RP(neutron) = 0.053). The crystal structure is of the A2BB′X6 elpasolite type with the a = b ≈ ae√5, c = 4ae superstructure (ae, parameter of the elpasolite subcell) and rock-salt-type ordering of the K and Al cations over the B and B′ positions, respectively. The remarkable feature of α-K3AlF6 is a rotation of 2/5 of the AlF6 octahedra by π/4 around one of the crystal axes of the elpasolite subcell, coinciding with the 4-fold symmetry axes of the AlF6 octahedra. The rotation of the AlF6 octahedra replaces the corner-sharing between the K and Al polyhedra by edge-sharing, resulting in an increase of coordination numbers of the K cations at the B positions up to 7 and 8. Due to significant deformations of the K polyhedra, the corner-sharing connectivity of the octahedral elpasolite framework is broken and the rotations of the AlF6 octahedra do not have a cooperative character. Elpasolites and double perovskites with similar structural organization are discussed. The difference in ionic radii of the B and B′ cations as well as the tolerance factor are proposed to be the parameters governing the formation of elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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Language |
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Wos |
000270091000039 |
Publication Date |
2009-09-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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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 |
20 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.857; 2009 IF: 4.657 |
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Call Number |
UA @ lucian @ c:irua:79733 |
Serial |
568 |
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| Permanent link to this record |
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Author |
Szafran, B.; Poniedziałek, M.R.; Peeters, F.M. |
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Title |
Violation of Onsager symmetry for a ballistic channel Coulomb coupled to a quantum ring |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
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Volume |
87 |
Issue |
4 |
Pages |
47002,1-47002,6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate a scattering of electron which is injected individually into an empty ballistic channel containing a cavity that is Coulomb coupled to a quantum ring charged with a single electron. We solve the time-dependent Schrödinger equation for the electron pair with an exact account for the electron-electron correlation. Absorption of energy and angular momentum by the quantum ring is not an even function of the external magnetic field. As a consequence we find that the electron backscattering probability is asymmetric in the magnetic field and thus violates Onsager symmetry. |
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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 |
Paris |
Editor |
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Language |
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Wos |
000270146400017 |
Publication Date |
2009-09-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0295-5075;1286-4854; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.957 |
Times cited |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.957; 2009 IF: 2.893 |
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Call Number |
UA @ lucian @ c:irua:79734 |
Serial |
3847 |
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Author |
Zha, G.-Q.; Chen, Y.; Peeters, F.M.; Zhou, S.-P. |
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Title |
Impurity-induced modulations of orders in d-wave superconductors |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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Volume |
80 |
Issue |
6 |
Pages |
064518,1-064518,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
By using a model Hamiltonian with competing antiferromagnetic (AFM) and d-wave superconductivity orders, the impurity-induced structures of orders in d-wave superconductors is investigated. We find that the transition between one-dimensional stripe and two-dimensional checkerboardlike modulation around a single nonmagnetic impurity can take place as the strength of the AFM interaction U or the impurity scattering strength V0 is varied. It is also found that the impurity-induced stripe can first transit to checkerboardlike modulation and then disappears with increasing the next-nearest-neighbor hopping strength |t|. Phase diagrams of V0 versus U and |t| for various modulations of the spin order are presented. In addition, the quantum interference effect on the modulations of orders due to two strong nonmagnetic impurities is briefly examined, and the checkerboardlike and quasistripe patterns can occur depending on the sites where two impurities are placed. |
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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 |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000269638800074 |
Publication Date |
2009-09-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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Call Number |
UA @ lucian @ c:irua:78293 |
Serial |
1572 |
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Author |
Launois, P.; Chorro, M.; Verberck, B.; Albouy, P.-A.; Rouzière, S.; Colson, D.; Forget, A.; Noé, L.; Kataura, H.; Monthioux, M.; Cambedouzou, J. |
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Title |
Transformation of C70 peapods into double walled carbon nanotubes |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
48 |
Issue |
1 |
Pages |
89-98 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
X-ray diffraction studies comparing the transformation of C(60) and C(70) peapods into double walled carbon nanotubes are presented. The structures of the as-formed DWCNTs are strikingly similar, showing that they are not dependent on the nature of the fullerene precursor. High temperature X-ray diffraction measurements of C(70) peapods below the coalescence temperature show that confined C(70) molecules in large tubes undergo an orientational. transition to free rotations. Fast re-orientations of C(70) molecules allow cyclo-addition between adjacent fullerenes to form, in good agreement with the mechanism of coalescence proposed in the literature for C(60) molecules. (C) 2009 Elsevier Ltd. 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 |
Oxford |
Editor |
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Language |
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Wos |
000272018800012 |
Publication Date |
2009-08-30 |
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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 |
0008-6223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.337 |
Times cited |
27 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 6.337; 2010 IF: 4.896 |
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Call Number |
UA @ lucian @ c:irua:94389 |
Serial |
3696 |
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Author |
van den Broek, W.; Van Aert, S.; van Dyck, D. |
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Title |
A model based atomic resolution tomographic algorithm |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
109 |
Issue |
12 |
Pages |
1485-1490 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Tomography with high angular annular dark field scanning transmission electron microscopy at atomic resolution can be greatly improved if one is able to take advantage of prior knowledge. In this paper we present a reconstruction technique that explicitly takes into account the microscope parameters and the atomic nature of the projected object. This results in a more accurate estimate of the atomic positions and in a good resistance to noise. The reconstruction is a maximum likelihood estimator of the object. Moreover, the limits to the precision have been explored, allowing for a prediction of the amount of expected noise in the reconstruction for a certain experimental setup. We believe that the proposed reconstruction technique can be generalized to other tomographic experiments. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000271840200010 |
Publication Date |
2009-08-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
17 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:78588 |
Serial |
2097 |
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Author |
Tarakina, N.V.; Zubkov, V.G.; Leonidov, I.I.; Tyutunnik, A.P.; Surat, L.L.; Hadermann, J.; Van Tendeloo, G. |
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Title |
Crystal structure of the group of optical materials Ln2MeGe4O12 (Me = Ca, Mn) |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Zeitschrift für Kristallographie |
Abbreviated Journal |
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Volume |
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Issue |
S:30 |
Pages |
401-406 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The crystal structure of the group of optical materials Ln2MeGe4O12, Ln = Eu, Gd, Dy-Lu, Y; Me = Ca, Mn and of the solid solution (Y1-xErx)2CaGe4O12 (x = 0 – 1), promising materials for photonics, has been studied in detail. The crystal structure of all compounds exhibit two alternating layers: one formed by Ln and Me atoms and another by cyclic [Ge4O12]8- anions. |
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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 |
München |
Editor |
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Language |
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Wos |
000271325700028 |
Publication Date |
2009-08-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0930-486X; |
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 |
7 |
Open Access |
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Notes |
Iap |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:79988 |
Serial |
575 |
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Author |
Tarakina, N.V.; Denisova, T.A.; Maksimova, L.G.; Baklanova, Y.V.; Tyutyunnik, A.P.; Berger, I.F.; Zubkov, V.G.; Van Tendeloo, G. |
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Title |
Investigation of stacking disorder in Li2SnO3 |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Zeitschrift für Kristallographie |
Abbreviated Journal |
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Volume |
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Issue |
S:30 |
Pages |
375-380 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A crystal structure investigation of the low temperature Li2SnO3 modification has been carried out. X-ray, neutron powder and electron diffraction data showed that this compound crystallizes in a monoclinic unit cell with parameters: a = 5.3033(2)Å, b = 9.1738(3)Å, c = 10.0195(2)Å, β ~ 100.042(2)º and has stacking disorder along the c-axis. Simulation of diffraction patterns with different stacking faults mainly reveal the presence of rotational stacking faults with a probability of about 40% . |
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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 |
München |
Editor |
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Language |
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Wos |
000271325700024 |
Publication Date |
2009-08-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0930-486X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
16 |
Open Access |
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Notes |
Iap |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:79987 |
Serial |
1735 |
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| Permanent link to this record |
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Author |
Zarenia, M.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. |
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Title |
Electrostatically confined quantum rings in bilayer graphene |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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Volume |
9 |
Issue |
12 |
Pages |
4088-4092 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We propose a new system where electron and hole states are electrostatically confined into a quantum ring in bilayer graphene. These structures can be created by tuning the gap of the graphene bilayer using nanostructured gates or by position-dependent doping. The energy levels have a magnetic field (B0) dependence that is strikingly distinct from that of usual semiconductor quantum rings. In particular, the eigenvalues are not invariant under a B0 ¨ −B0 transformation and, for a fixed total angular momentum index m, their field dependence is not parabolic, but displays two minima separated by a saddle point. The spectra also display several anticrossings, which arise due to the overlap of gate-confined and magnetically confined states. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington |
Editor |
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Language |
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Wos |
000272395400023 |
Publication Date |
2009-08-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1530-6984;1530-6992; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
12.712 |
Times cited |
42 |
Open Access |
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Notes |
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Approved |
Most recent IF: 12.712; 2009 IF: 9.991 |
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Call Number |
UA @ lucian @ c:irua:80318 |
Serial |
1024 |
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| Permanent link to this record |
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Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
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| |
Title |
Tunneling-lifetime model for metal-oxide-semiconductor structures |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
80 |
Issue |
8 |
Pages |
085315,1-085315,10 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
In this paper we investigate the basic physics of charge carriers (electrons) leaking out of the inversion layer of a metal-oxide-semiconductor capacitor with a biased gate. In particular, we treat the gate leakage current as resulting from two combined processes: (1) the time-dependent decay of electron wave packets representing the inversion-layer charge and (2) the local generation of new electrons replacing those that have leaked away. As a result, the gate current simply emerges as the ratio of the total charge in the inversion layer to the tunneling lifetime. The latter is extracted from the quantum dynamics of the decaying wave packets, while the generation rate is incorporated as a phenomenological source term in the continuity equation. Not only do the gate currents calculated with this model agree very well with experiment, the model also provides an onset to solve the paradox of the current-free bound states representing the resonances of the Schrödinger equation that governs the fully coupled metal-oxide-semiconductor system. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
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| |
Language |
|
Wos |
000269639300076 |
Publication Date |
2009-08-21 |
|
| |
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 |
2 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
|
| |
Call Number |
UA @ lucian @ c:irua:78294 |
Serial |
3763 |
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| Permanent link to this record |
| |
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| |
|
Author |
Dhong, H.M.; Zhang, J.; Peeters, F.M.; Xu, W. |
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| |
Title |
Optical conductance and transmission in bilayer graphene |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
| |
Volume |
106 |
Issue |
4 |
Pages |
043103,1-043103,6 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We present a theoretical study of the optoelectronic properties of bilayer graphene. The optical conductance and transmission coefficient are calculated using the energy-balance equation derived from a Boltzmann equation for an air/graphene/dielectric-wafer system. For short wavelengths (<0.2 µm), we obtain the universal optical conductance =e2/(2). Interestingly, there exists an optical absorption window in the wavelength range 10100 µm, which is induced by different transition energies required for inter- and intra-band optical absorptions in the presence of the MossBurstein effect. As a result, the position and width of this absorption window depend sensitively on temperature, carrier density, and sample mobility of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
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| |
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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|
| |
Language |
|
Wos |
000270083800004 |
Publication Date |
2009-08-20 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.068 |
Times cited |
11 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
|
| |
Call Number |
UA @ lucian @ c:irua:79315 |
Serial |
2472 |
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| Permanent link to this record |
| |
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| |
|
Author |
Wang, M.; Chang, K.; Wang, L.G.; Dai, N.; Peeters, F.M. |
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| |
Title |
Crystallographic plane tuning of charge and spin transport in semiconductor quantum wires |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
20 |
Issue |
36 |
Pages |
365202,1-365202,8 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We investigate theoretically the charge and spin transport in quantum wires grown along different crystallographic planes in the presence of the Rashba spinorbit interaction (RSOI) and the Dresselhaus spinorbit interaction (DSOI). We find that changing the crystallographic planes leads to a variation of the anisotropy of the conductance due to a different interplay between the RSOI and DSOI, since the DSOI is induced by bulk inversion asymmetry, which is determined by crystallographic plane. This interplay depends sensitively on the crystallographic planes, and consequently leads to the anisotropic charge and spin transport in quantum wires embedded in different crystallographic planes. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
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|
| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
| |
Language |
|
Wos |
000269077000003 |
Publication Date |
2009-08-19 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
14 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.44; 2009 IF: 3.137 |
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| |
Call Number |
UA @ lucian @ c:irua:78933 |
Serial |
588 |
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| Permanent link to this record |
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| |
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Author |
Berdiyorov, G.R.; Yu, S.H.; Xiao, Z.L.; Peeters, F.M.; Hua, J.; Imre, A.; Kwok, W.K. |
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| |
Title |
Effect of sample geometry on the phase boundary of a mesoscopic superconducting loop |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
80 |
Issue |
6 |
Pages |
064511,1-064511,6 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We studied the effect of sample geometry on the evolution of the superconducting state in nanoscale Nb circular and square loops by transport measurements. A multistage resistive transition with temperature is found for both samples, which is related to the effect of contact leads made from the same superconducting material. The H-T phase diagrams close to Tc0 show clear periodic oscillations on top of a parabolic background, i.e., Little-Parks effect. However, the amplitude of the oscillations decreases faster in the circular loop compared to the one in the square sample. Numerical simulations are conducted within the nonlinear Ginzburg-Landau theory to show the effect of sample geometry on the nucleation of superconductivity in superconducting loop structures. |
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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 |
Lancaster, Pa |
Editor |
|
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| |
Language |
|
Wos |
000269638800067 |
Publication Date |
2009-08-17 |
|
| |
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 |
21 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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| |
Call Number |
UA @ lucian @ c:irua:78292 |
Serial |
833 |
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| Permanent link to this record |
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| |
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Author |
van der Linden, V.; Schalm, O.; Houbraken, J.; Thomas, M.; Meesdom, E.; Devos, A.; van Dooren, R.; Nieuwdorp, H.; Janssen, E.; Janssens, K. |
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| |
Title |
Chemical analysis of 16th to 19th century Limoges School painted enamel objects in three museums of the Low Countries |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
X-Ray Spectrom |
|
| |
Volume |
39 |
Issue |
2 |
Pages |
112-121 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
In this study, the results of analysing of a series of 16th-19th century painted enamel objects of the Limoges School currently in collections in three Dutch and Flemish museums by means of portable and micro x-ray fluorescence analysis (PXRF and µ-XRF) and electron probe micro analysis (EPMA) are presented. The aim of the investigation was the authentication of specific pieces. Therefore, the glass compositions as well as the (glass) colouring agents used by the Limoges' artists were studied as a function of the age of the objects. Due to the evolution of these properties, it is possible to approximately date these objects based on their chemical composition. The complete émail peint collection of the Museum Boijmans-Van Beuningen (Rotterdam, The Netherlands), consisting of 20 émail peint plaques, was analysed with µ-XRF. Quantitative information was obtained by EPMA analysis of 15 enamel fragments of objects from museum and private collections in the Low Countries. PXRF analyses were performed on the painted enamel collection of the Antwerp Vleeshuis Museum (13 objects) and the Mayer van den Bergh Museum (4 objects) and on a set of 18 plaques that were donated to the Boijmans-Van Beuningen Museum by a private collector. The results obtained by means of EPMA, µ-XRF and PXRF proved to be useful in the discrimination of 16th century painted enamel objects from those of the19th century. From a total of 70 objects examined, 2 objects (OM964A and OM993) featured a chemical signature that deviated from the published literature composition and pigment use consistent with its presumed period of manufacture. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000275959400007 |
Publication Date |
2009-08-11 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.298 |
Times cited |
8 |
Open Access |
|
|
| |
Notes |
; ; |
Approved |
Most recent IF: 1.298; 2010 IF: 1.661 |
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| |
Call Number |
UA @ admin @ c:irua:82325 |
Serial |
5509 |
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| Permanent link to this record |
| |
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| |
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Author |
Zhang, H.; Yang, J.-H.; Shpanchenko, R.V.; Abakumov, A.M.; Hadermann, J.; Clérac, R.; Dikarev, E.V. |
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| |
Title |
New class of single-source precursors for the synthesis of main group-transition metal oxides: heterobimetallic Pb-Mn \beta-diketonates |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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| |
Volume |
48 |
Issue |
17 |
Pages |
8480-8488 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Heterometallic lead−manganese â-diketonates have been isolated in pure form by several synthetic methods that include solid-state and solution techniques. Two compounds with different Pb/Mn ratios, PbMn2(hfac)6 (1) and PbMn(hfac)4 (2) (hfac = hexafluoroacetylacetonate), can be obtained in quantitative yield by using different starting materials. Single crystal X-ray investigation revealed that the solid-state structure of 1 contains trinuclear molecules in which lead metal center is sandwiched between two [Mn(hfac)3] units, while 2 consists of infinite chains of alternating [Pb(hfac)2] and [Mn(hfac)2] fragments. The heterometallic structures are held together by strong Lewis acid−base interactions between metal atoms and diketonate ligands acting in chelating-bridging fashion. Spectroscopic investigation confirmed the retention of heterometallic structures in solutions of non-coordinating solvents as well as upon sublimation-deposition procedure. Thermal decomposition of heterometallic diketonates has been systematically investigated in a wide range of temperatures and annealing times. For the first time, it has been shown that thermal decomposition of heterometallic diketonates results in mixed-metal oxides, while both the structure of precursors and the thermolysis conditions have a significant influence on the nature of the resulting oxides. Five different Pb−Mn oxides have been detected by X-ray powder diffraction when studying the decomposition of 1 and 2 in the temperature range 500−800 °C. The phase that has been previously reported as Pb0.43MnO2.18 was synthesized in the pure form by decomposition of 1, and crystallographically characterized. The orthorhombic unit cell parameters of this oxide, obtained by electron diffraction technique, have been subsequently refined using X-ray powder diffraction data. Besides that, a previously unknown lead−manganese oxide has been obtained at low temperature decomposition and short annealing times. The parameters of its monoclinically distorted unit cell have been determined. The EDX analysis revealed that this compound has a Pb/Mn ratio close to 1:4 and contains no appreciable amount of fluorine. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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| |
Language |
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Wos |
000269313500056 |
Publication Date |
2009-08-04 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
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| |
ISSN |
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 |
28 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 4.857; 2009 IF: 4.657 |
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| |
Call Number |
UA @ lucian @ c:irua:78486 |
Serial |
2308 |
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| Permanent link to this record |
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| |
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Author |
Hao, Y.L.; Djotyan, A.P.; Avetisyan, A.A.; Peeters, F.M. |
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| |
Title |
Shallow donor states near a semiconductor-insulator-metal interface |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
80 |
Issue |
3 |
Pages |
035329,1-035329,10 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The lowest energy electronic states of a donor located near a semiconductor-insulator-metal interface are investigated within the effective mass approach. The effect of the finite thickness of the insulator between the semiconductor and the metallic gate on the energy levels is studied. The lowest energy states are obtained through a variational approach, which takes into account the influence of all image charges that arise due to the presence of the metallic and the dielectric interfaces. We compare our results with a numerical exact calculation using the finite element technique. |
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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 |
Lancaster, Pa |
Editor |
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| |
Language |
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Wos |
000268617800101 |
Publication Date |
2009-07-30 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
22 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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| |
Call Number |
UA @ lucian @ c:irua:77950 |
Serial |
2989 |
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| Permanent link to this record |
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| |
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Author |
Van Aert, S.; Verbeeck, J.; Bals, S.; Erni, R.; van Dyck, D.; Van Tendeloo, G. |
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| |
Title |
Atomic resolution mapping using quantitative high-angle annular dark field scanning transmission electron microscopy |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
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| |
Volume |
15 |
Issue |
S:2 |
Pages |
464-465 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Cambridge, Mass. |
Editor |
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| |
Language |
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Wos |
000208119100230 |
Publication Date |
2009-07-27 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.891 |
Times cited |
1 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 1.891; 2009 IF: 3.035 |
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| |
Call Number |
UA @ lucian @ c:irua:96555UA @ admin @ c:irua:96555 |
Serial |
178 |
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| Permanent link to this record |
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Author |
Lepoittevin, C.; Hadermann, J.; Malo, S.; Pérez, O.; Van Tendeloo, G.; Hervieu, M. |
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| |
Title |
Two variants of the 1/2[110]p(203)p crystallographic shear structures: the phasoid Sr0.61Pb0.18(Fe0.75Mn0.25)O2.29 |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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| |
Volume |
48 |
Issue |
17 |
Pages |
8257-8262 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
For the composition (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29, a new modulated crystallographic shear structure, related to perovskite, has been synthesized and structurally characterized by transmission electron microscopy. The structure can be described using a monoclinic supercell with cell parameters am = 27.595(2) Å, bm = 3.8786(2) Å, cm = 13.3453(9) Å, and βm = 100.126(5)°, refined from powder X-ray diffraction data. The incommensurate crystallographic shear phases require an alternative approach using the superspace formalism. This allows a unified description of the incommensurate phases from a monoclinically distorted perovskite unit cell and a modulation wave vector. The structure deduced from the high-resolution transmission electron microscopy and high-angle annular dark-field−scanning transmission electron microscopy images is that of a 1/2[110]p(203)p crystallographic shear structure. The structure follows the concept of a phasoid, with two coexisting variants with the same unit cell. The difference is situated at the translational interface, with the local formation of double (phase 2) or single (phase 1) tunnels, where the Pb cations are likely located. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Easton, Pa |
Editor |
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| |
Language |
|
Wos |
000269313500032 |
Publication Date |
2009-07-24 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.857 |
Times cited |
11 |
Open Access |
|
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.857; 2009 IF: 4.657 |
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| |
Call Number |
UA @ lucian @ c:irua:78482 |
Serial |
3786 |
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| Permanent link to this record |
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| |
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Author |
Tian, H.; Schryvers, D.; Mohanchandra, K.P.; Carman, G.P.; van Humbeeck, J. |
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| |
Title |
Fabrication and characterization of functionally graded Ni-Ti multilayer thin films |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Functional materials letters |
Abbreviated Journal |
Funct Mater Lett |
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| |
Volume |
2 |
Issue |
2 |
Pages |
61-66 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
A functionally graded multilayer NiTi thin film was deposited on a SiO2/Si substrate by d.c. sputtering using a ramped heated NiTi alloy target. The stand-alone films were crystallized at 500°C in vacuum better than 10-7 Torr. Transmission electron microscopy micrographs taken along the film cross section show two distinct regions, thin and thick, with weak R and B2 phases, respectively. The film compositions along the thickness were measured and quantified using the standard-less EELSMODEL method. The film deposited during the initial thermal ramp (thin regions) displays an average of 54 at.% Ni while the film deposited at a more elevated target temperature (thick regions) shows about 51 at.% Ni. |
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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 |
|
Editor |
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| |
Language |
|
Wos |
000271077000003 |
Publication Date |
2009-07-22 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1793-6047;1793-7213; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.234 |
Times cited |
9 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 1.234; 2009 IF: 2.561 |
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| |
Call Number |
UA @ lucian @ c:irua:77655 |
Serial |
1165 |
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| Permanent link to this record |
| |
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| |
|
Author |
Malard, B.; Pilch, J.; Sittner, P.; Gartnerova, V.; Delville, R.; Schryvers, D.; Curfs, C. |
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| |
Title |
Microstructure and functional property changes in thin Ni-Ti wires heat teated by electric current: high energy X-ray and TEM investigations |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Functional materials letters |
Abbreviated Journal |
Funct Mater Lett |
|
| |
Volume |
2 |
Issue |
2 |
Pages |
45-54 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
High energy synchrotron X-ray diffraction, transmission electron microscopy and mechanical testing were employed to investigate the evolution of microstructure, texture and functional superelastic properties of 0.1 mm thin as drawn NiTi wires subjected to a nonconventional heat treatment by controlled electric current (FTMT-EC method). As drawn NiTi wires were prestrained in tension and exposed to a sequence of short DC power pulses in the millisecond range. The annealing time in the FTMT-EC processing can be very short but the temperature and force could be very high compared to the conventional heat treatment of SMAs. It is shown that the heavily strained, partially amorphous microstructure of the as drawn NiTi wire transforms under the effect of the DC pulse and tensile stress into a wide range of annealed nanosized microstructures depending on the pulse time. The functional superelastic properties and microstructures of the FTMT-EC treated NiTi wire are comparable to those observed in straight annealed wires. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000271077000001 |
Publication Date |
2009-07-22 |
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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 |
1793-6047;1793-7213; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.234 |
Times cited |
21 |
Open Access |
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| |
Notes |
Multimat |
Approved |
Most recent IF: 1.234; 2009 IF: 2.561 |
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| |
Call Number |
UA @ lucian @ c:irua:77656 |
Serial |
2052 |
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| Permanent link to this record |
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| |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
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| |
Title |
Superconducting nanowires: interplay of discrete transverse modes with supercurrent |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
80 |
Issue |
2 |
Pages |
024513,1-024513,11 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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| |
Abstract |
From a numerical solution of the Bogoliubov-de Gennes equations, we investigate an interplay of the transverse discrete modes with a longitudinal supercurrent in a metallic cylindrical superconducting nanowire. The superconductor-to-normal transition induced by a longitudinal superflow of electrons is found to occur as a cascade of jumps in the order parameter (supercurrent and superfluid density) as a function of the superfluid velocity for diameters d<1015 nm (for Al parameters) and sufficiently low temperatures T<0.30.4Tc, with Tc the critical temperature. When approaching Tc, the jumps are smoothed into steplike but continuous drops. A similar picture occurs for d>1520 nm. Only when the diameter exceeds 5070 nm the quantum-size cascades are fully washed out, and we arrive at the mesoscopic regime. Below this regime the critical current density jc exhibits the quantum-size oscillations with pronounced resonant enhancements: the smaller the diameter, the more significant is the enhancement. Thickness fluctuations of real samples will smooth out such oscillations into an overall growth of jc with decreasing nanowire diameter. |
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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 |
Lancaster, Pa |
Editor |
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| |
Language |
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Wos |
000268617500092 |
Publication Date |
2009-07-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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| |
Call Number |
UA @ lucian @ c:irua:77949 |
Serial |
3358 |
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| Permanent link to this record |
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Author |
Ke, X.; Bals, S.; Romo Negreira, A.; Hantschel, T.; Bender, H.; Van Tendeloo, G. |
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Title |
TEM sample preparation by FIB for carbon nanotube interconnects |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
109 |
Issue |
11 |
Pages |
1353-1359 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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| |
Language |
|
Wos |
000270765800006 |
Publication Date |
2009-07-11 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.843 |
Times cited |
21 |
Open Access |
|
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| |
Notes |
Esteem 026019; Iap |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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| |
Call Number |
UA @ lucian @ c:irua:79074 |
Serial |
3485 |
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| Permanent link to this record |
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Author |
Schweigert, V.A.; Peeters, F.M. |
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Title |
Dynamics of a finite classical two-dimensional system |
Type |
A1 Journal article |
| |
Year |
1994 |
Publication |
Superlattices and microstructures |
Abbreviated Journal |
Superlattice Microst |
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Volume |
16 |
Issue |
3 |
Pages |
243-247 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The spectral properties of a classical two-dimensional (2D) cluster of charged particles which are confined by a quadratic potential are calculated. Using the method of Newton optimization we obtain the ground state and the metastable states. For a given configuration the eigenvectors and eigenfrequencies for the normal modes are obtained using the Householder diagonalization technique for the dynamical matrix whose elements are the second derivative of the potential energy. For small clusters the lowest excitation corresponds to an intershell rotation. Magic numbers are associated to clusters which are most stable against intershell rotation. For large clusters the lowest excitation is a vortex/anti-vortex pair. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
A1994QE75400007 |
Publication Date |
2009-07-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0749-6036; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.097 |
Times cited |
4 |
Open Access |
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| |
Notes |
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Approved |
no |
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| |
Call Number |
UA @ lucian @ c:irua:99951 |
Serial |
772 |
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| Permanent link to this record |
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Author |
Verbeeck, J.; Bertoni, G. |
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Title |
Deconvolution of core electron energy loss spectra |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
109 |
Issue |
11 |
Pages |
1343-1352 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Different deconvolution methods for removing multiple scattering and instrumental broadening from core loss electron energy loss spectra are compared with special attention to the artefacts they introduce. The Gaussian modifier method, Wiener filter, maximum entropy, and model based methods are described. Their performance is compared on virtual spectra where the true single scattering distribution is known. A test on experimental spectra confirms the good performance of model based deconvolution in comparison to maximum entropy methods and shows the advantage of knowing the estimated error bars from a single spectrum acquisition. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000270765800005 |
Publication Date |
2009-07-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
13 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:79073UA @ admin @ c:irua:79073 |
Serial |
610 |
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| Permanent link to this record |
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Author |
Hadermann, J.; Abakumov, A.M.; Adkin, J.J.; Hayward, M.A. |
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Title |
Topotactic reduction as a route to new close-packed anion deficient perovskites: structure and magnetism of 4H-BaMnO2+x |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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| |
Volume |
131 |
Issue |
30 |
Pages |
10598-10604 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The anion-deficient perovskite 4H-BaMnO2+x has been obtained by a topotactic reduction, with LiH, of the hexagonal perovskite 4H-BaMnO3−x. The crystal structure of 4H-BaMnO2+x was solved using electron diffraction and X-ray powder diffraction and further refined using neutron powder diffraction (S.G. Pnma, a = 10.375(2) Å, b = 9.466(2) Å, c = 11.276(3) Å, at 373 K). The orthorhombic superstructure arises from the ordering of oxygen vacancies within a 4H (chch) stacking of close packed c-type BaO2.5 and h-type BaO1.5 layers. The ordering of the oxygen vacancies transforms the Mn2O9 units of face-sharing MnO6 octahedra into Mn2O7 (two corner-sharing tetrahedra) and Mn2O6 (two edge-sharing tetrahedra) groups. The Mn2O7 and Mn2O6 groups are linked by corner-sharing into a three-dimensional framework. The structures of the BaO2.5 and BaO1.5 layers are different from those observed previously in anion-deficient perovskites providing a new type of order pattern of oxygen atoms and vacancies in close packed structures. Magnetization measurements and neutron diffraction data reveal 4H-BaMnO2+x adopts an antiferromagnetically ordered state below TN ≈ 350 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 |
Washington, D.C. |
Editor |
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Language |
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Wos |
000268644400056 |
Publication Date |
2009-07-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
13.858 |
Times cited |
25 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 13.858; 2009 IF: 8.580 |
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Call Number |
UA @ lucian @ c:irua:77928 |
Serial |
3681 |
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| Permanent link to this record |
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Author |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
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Title |
Water on graphene: hydrophobicity and dipole moment using density functional theory |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
79 |
Issue |
23 |
Pages |
235440,1-235440,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We apply density-functional theory to study the adsorption of water clusters on the surface of a graphene sheet and find i) graphene is highly hydrophobic and ii) adsorbed water has very little effect on the electronic structure of graphene. A single water cluster on graphene has a very small average dipole moment which is in contrast with an ice layer that exhibits a strong dipole moment. |
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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 |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000267699500147 |
Publication Date |
2009-06-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
292 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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Call Number |
UA @ lucian @ c:irua:77693 |
Serial |
3904 |
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| Permanent link to this record |
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Author |
Baguer, N.; Georgieva, V.; Calderin, L.; Todorov, I.T.; van Gils, S.; Bogaerts, A. |
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Title |
Study of the nucleation and growth of TiO2 and ZnO thin films by means of molecular dynamics simulations |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of crystal growth |
Abbreviated Journal |
J Cryst Growth |
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| |
Volume |
311 |
Issue |
16 |
Pages |
4034-4043 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The nucleation and growth of titanium dioxide (TiO2) and zinc oxide (ZnO) thin films on Fe2O3 (hematite), Al2O3 (á-alumina) and SiO2 (á-quartz) are studied by molecular dynamics simulations. The results show the formation of a strong interface region between the substrate and the film in the six systems studied here. A combination of polycrystalline and amorphous phases are observed in the TiO2 films grown on the three substrates. ZnO deposition on the Fe2O3 and Al2O3 crystals yields a monocrystalline film growth. The ZnO film deposited on the SiO2 crystal exhibits less crystallinity. The simulation results are compared with experimental results available in the literature. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000269580100012 |
Publication Date |
2009-06-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-0248; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.751 |
Times cited |
23 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 1.751; 2009 IF: 1.534 |
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Call Number |
UA @ lucian @ c:irua:77453 |
Serial |
3338 |
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| Permanent link to this record |
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Author |
Pop, N.; Pralong, V.; Caignaert, V.; Colin, J.F.; Malo, S.; Van Tendeloo, G.; Raveau, B. |
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Title |
Topotactic transformation of the cationic conductor Li4Mo5O17 into a rock salt type oxide Li12Mo5O17 |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
21 |
Issue |
14 |
Pages |
3242-3250 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Intercalation of lithium in the ribbon structure Li4Mo5O17 has been achieved, using both electrochemistry and soft chemistry. The ab initio structure determination of the ¡°Mo−O¡± framework of Li12Mo5O17 shows that the [Mo5O17]¡Þ ribbons keep the same arrangement of edge sharing MoO6 octahedra and the same orientation as in the parent structure but that a topotactic antidistortion of the ribbons appears, as a result of the larger size of Mo4+ in ¡°Li12¡± compared to Mo6+ in ¡°Li4¡±. On the basis of bond valence calculations, it is observed that 12 octahedral sites are available for Li+ in the new structure so that an ordered hypothetical rock salt type structure can be proposed for Li12Mo5O17. After the first Li insertion, a stable reversible capacity of 100 mA¡¤h/g is maintained after 20 cycles. A complete structural reversibility leading back to the ribbon type Li4Mo5O17 structure is obtained using a very low rate of C/100. The exploration of the Li mobility in those oxides shows that Li4Mo5O17 is a cationic conductor with ¦Ò = 10−3.5 S/cm at 500 ¡ãC and Ea = 0.35 eV. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000268174400032 |
Publication Date |
2009-06-24 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
18 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
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| |
Call Number |
UA @ lucian @ c:irua:78285 |
Serial |
3682 |
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| Permanent link to this record |
