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Records |
Links |
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Author |
Moshnyaga, V.; Damaschke, B.; Shapoval, O.; Belenchuk, A.; Faupel, J.; Lebedev, O.I.; Verbeeck, J.; Van Tendeloo, G.; Mücksch, M.; Tsurkan, V.; Tidecks, R.; Samwer, K. |
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| |
Title |
Structural phase transition at the percolation threshold in epitaxial (La0.7Ca0.3MnO3)1-x:(MgO)x nanocomposite films |
Type |
A1 Journal article |
| |
Year |
2003 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
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| |
Volume |
2 |
Issue  |
4 |
Pages |
247-252 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
'Colossal magnetoresistance' in perovskite manganites such as La0.7Ca0.3MnO3 (LCMO), is caused by the interplay of ferro-paramagnetic, metal-insulator and structural phase transitions. Moreover, different electronic phases can coexist on a very fine scale resulting in percolative electron transport. Here we report on (LCMO)(1-x):(MgO)(x) (0 < x less than or equal to 0.8) epitaxial nano-composite films in which the structure and magnetotransport properties of the manganite nanoclusters can be tuned by the tensile stress originating from the MgO second phase. With increasing x, the lattice of LCMO was found to expand, yielding a bulk tensile strain. The largest colossal magnetoresistance of 10(5)% was observed at the percolation threshold in the conductivity at x(c) approximate to 0.3, which is coupled to a structural phase transition from orthorhombic (0 < x less than or equal to 0.1) to rhombohedral R (3) over barc structure (0.33 less than or equal to x less than or equal to 0.8). An increase of the Curie temperature for the R (3) over barc phase was observed. These results may provide a general method for controlling the magnetotransport properties of manganite-based composite films by appropriate choice of the second phase. |
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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 |
000182052700022 |
Publication Date |
2003-03-31 |
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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 |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
39.737 |
Times cited |
177 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 39.737; 2003 IF: 10.778 |
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| |
Call Number |
UA @ lucian @ c:irua:54855 |
Serial |
3247 |
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| Permanent link to this record |
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Author |
Hervieu, M.; Van Tendeloo, G.; Schuddinck, W.; Richard, O.; Caignaert, V.; Millange, F.; Raveau, B. |
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| |
Title |
Structural phase transition in the manganite Nd0.5Ca0.2Sr0.3MnO3-\delta |
Type |
A1 Journal article |
| |
Year |
1997 |
Publication |
Journal of electron microscopy |
Abbreviated Journal |
Microscopy-Jpn |
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| |
Volume |
46 |
Issue |
4 |
Pages |
263-269 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Tokyo |
Editor |
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Language |
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Wos |
A1997XY94900001 |
Publication Date |
0000-00-00 |
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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 |
0022-0744; 1477-9986 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
0.9 |
Times cited |
2 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:21446 |
Serial |
3249 |
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| Permanent link to this record |
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Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
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| |
Title |
Structure and stability of Fe2 phases from density-functional theory calculations |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
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| |
Volume |
63 |
Issue |
4 |
Pages |
418-421 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Fe(2)C plays a crucial role in the precipitation of iron carbides. Jack's structural models for epsilon-Fe(2)C, and non-stoichiometric epsilon-Fe(2.4)C, are analyzed using first-principles calculations. Several new configurations of epsilon-Fe(2)C with even higher stability are found. We show how epsilon-Fe(2)C transforms into eta-Fe(2)C, and address the structural relationships with the chi-Fe(5)C(2), theta-Fe(3)C and Fe(7)C(3) phases. The relative occurrence of these phases in steel, as well as their probable evolution during tempering of quenched steels, is discussed. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. |
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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 |
Oxford |
Editor |
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Language |
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Wos |
000279496000017 |
Publication Date |
2010-05-03 |
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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 |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.747 |
Times cited |
32 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 3.747; 2010 IF: 2.820 |
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| |
Call Number |
UA @ lucian @ c:irua:95591 |
Serial |
3299 |
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| Permanent link to this record |
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| |
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Author |
Colomer, J.-F.; Henrard, L.; Van Tendeloo, G.; Lucas, A.; Lambin, P. |
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| |
Title |
Study of the packing of double-walled carbon nanotubes into bundles by transmission electron microscopy and electron diffraction |
Type |
A1 Journal article |
| |
Year |
2004 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
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| |
Volume |
14 |
Issue |
4 |
Pages |
603-606 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000220224100021 |
Publication Date |
2004-02-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
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 |
|
Times cited |
27 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:54758 |
Serial |
3339 |
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| Permanent link to this record |
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Author |
Chen, L.; Kirilenko, D.; Stesmans, A.; Nguyen, X.S.; Binnemans, K.; Goderis, B.; Vanacken, J.; Lebedev, O.; Van Tendeloo, G.; Moshchalkov, V.V. |
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| |
Title |
Symmetry and electronic states of Mn2+ in ZnS nanowires with mixed hexagonal and cubic stacking |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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| |
Volume |
97 |
Issue |
4 |
Pages |
041918,1-041918,3 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Electron spin resonance and electronic spectroscopy techniques were used to study the symmetry and electronic structure of Mn2+ dopants in solvothermally synthesized ZnS nanowires. The average diameter of ∼ 5 nm leads to the observable quantum confinement effects in the photoluminescence excitation spectra. The results clearly demonstrate the three symmetry locations of Mn2+ incorporation. Together with the inferred Mn2+ center densities, these data indicate a much higher efficiency of Mn2+ substitution in the nanowire sample with about two times larger diameter. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000281059200038 |
Publication Date |
2010-08-02 |
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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 |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.411 |
Times cited |
5 |
Open Access |
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| |
Notes |
Methusalem |
Approved |
Most recent IF: 3.411; 2010 IF: 3.841 |
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| |
Call Number |
UA @ lucian @ c:irua:84869 |
Serial |
3403 |
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| Permanent link to this record |
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Author |
Esquivel, M.R.; Zelaya, E. |
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| |
Title |
Synthesis and characterisation of lanthanide-based dioxide |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Advances in applied ceramics |
Abbreviated Journal |
Adv Appl Ceram |
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| |
Volume |
110 |
Issue |
4 |
Pages |
219-224 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
In the present work, the microstructure and structure of La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)(OH)(3) and La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)O(2) is obtained from transmission electron microscopy and X-ray diffraction measurements. Space group P6(3)/m is assigned to the structure of La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)(OH)(3). Lanthanides are assigned to Wyckoff positions 2c. Cell parameters are a=6.375(5) angstrom and c=3.753(5) angstrom. The thermal decomposition of this compound was studied by differential scanning calorimetry. The process is exothermal with an enthalpy change Delta H degrees value of -254 +/- 10 kJ mol(-1). The decomposition kinetics is complex and two global processes with E(a) values of 98 +/- 4 and 61 +/- 2 kJ mol 21 were observed. The product is a lanthanide dioxide. Space group Fm3m is assigned to the La(0.25)Ce(0.52)Nd(0.17)Pr(0.06)O(2). Lanthanides are distributed in Wyckoff positions 4a. The cell parameter is a=5.479(5) angstrom. Nanopores in the oxide surface are obtained using this method and characterised by STEM measurements. |
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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 |
Leeds |
Editor |
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| |
Language |
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Wos |
000291206700006 |
Publication Date |
2011-05-30 |
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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 |
1743-6753;1743-6761; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.325 |
Times cited |
3 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 1.325; 2011 IF: 0.871 |
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| |
Call Number |
UA @ lucian @ c:irua:105588 |
Serial |
3410 |
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| Permanent link to this record |
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Author |
Kalyuzhnaya, A.S.; Abakumov, A.M.; Rozova, M.G.; d' Hondt, H.; Hadermann, J.; Antipov, E.V. |
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| |
Title |
Synthesis and crystal structure of the new complex oxide Ca7Mn2.14Ga5.86O17.93 |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Russian chemical bulletin |
Abbreviated Journal |
Russ Chem B+ |
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| |
Volume |
59 |
Issue |
4 |
Pages |
706-711 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The complex oxide Ca7Mn2.14Ga5.86O17.93 was synthesized by the solid-state reaction in a sealed evacuated quartz tube at 1000 °C. Its crystal structure was determined by electron diffraction and X-ray powder diffraction. The structure can be represented as a tetrahedral framework, viz., the polyanion [(Mn0.285Ga0.715)15O29.86]19- stabilized by the incorporated cation [Ca14GaO6]19+. The polycation consists of the GaO6 octahedra surrounded by the Ca atoms, which are arranged to form a cube capped at all places. The tetrahedral framework is partially disordered due to the presence of tetrahedra with two possible orientations in the positions (0, 0, 0) and (x, x, x) with x ≈ 0.15 and 0.17. The relationship between the Ca7Mn2.14Ga5.86O17.93 structures and related ordered phases with the symmetry F23, as well as the influence of the oxygen content on the ordering in the tetrahedral framework, are discussed. |
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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 |
000283302000006 |
Publication Date |
2010-10-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1066-5285;1573-9171; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
0.529 |
Times cited |
1 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 0.529; 2010 IF: 0.629 |
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| |
Call Number |
UA @ lucian @ c:irua:85675 |
Serial |
3427 |
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| Permanent link to this record |
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Author |
Morozov, V.A.; Mironov, A.V.; Lazoryak, B.I.; Khaikina, E.G.; Basovich, O.M.; Rossell, M.D.; Van Tendeloo, G. |
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Title |
Ag1/8Pr5/8MoO4: an incommensurately modulated scheelite-type structure |
Type |
A1 Journal article |
| |
Year |
2006 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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| |
Volume |
179 |
Issue |
4 |
Pages |
1183-1191 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000236501300029 |
Publication Date |
2006-02-08 |
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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 |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.299 |
Times cited |
35 |
Open Access |
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| |
Notes |
Iap V-1 |
Approved |
Most recent IF: 2.299; 2006 IF: 2.107 |
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| |
Call Number |
UA @ lucian @ c:irua:57766 |
Serial |
3513 |
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| Permanent link to this record |
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Author |
Kifune, K.; Yamamoto, K.; Maruyama, S.; Van Tendeloo, G. |
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Title |
The domain configuration of the Au11In3 phase |
Type |
A1 Journal article |
| |
Year |
1994 |
Publication |
Philosophical magazine letters |
Abbreviated Journal |
Phil Mag Lett |
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| |
Volume |
69 |
Issue |
4 |
Pages |
211-214 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The crystal structure of Au11In3 thin film alloys have been analysed by means of electron diffraction and high-resolution electron microscopy. The electron diffraction pattern and the high-resolution electron microscopy revealed that this structure was incommensurate and had a domain structure consisting of three kinds of structural unit. The approximant structural model, which is based on a h.c.p. stacking of the layers, is hexagonal with lattice parameters a = 7.612 nm and c = 0-478 nm. |
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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 |
A1994NE53100007 |
Publication Date |
2007-07-08 |
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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 |
0950-0839;1362-3036; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.087 |
Times cited |
2 |
Open Access |
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| |
Notes |
|
Approved |
PHYSICS, APPLIED 47/145 Q2 # |
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| |
Call Number |
UA @ lucian @ c:irua:95438 |
Serial |
3574 |
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| Permanent link to this record |
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| |
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Author |
Ivanov, V.; Nagy, J.B.; Lambin, P.; Lucas, A.; Zhang, X.B.; Zhang, X.F.; Bernaerts, D.; Van Tendeloo, G.; Amelinckx, S.; van Landuyt, J. |
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Title |
The study of carbon nanotubules produced by catalytic method |
Type |
A1 Journal article |
| |
Year |
1994 |
Publication |
Chemical physics letters |
Abbreviated Journal |
Chem Phys Lett |
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| |
Volume |
223 |
Issue |
4 |
Pages |
329-335 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Catalytic methods for the production of carbon nanotubules have been developed based on the decomposition of acetylene on well-dispersed metal particles strongly adsorbed on a support. Cobalt on silica was found to be the best catalyst-support combination for the production of graphitic tubules. The method for the catalyst preparation and the reaction conditions were optimized. Straight and coiled carbon tubules were obtained with inner and outer diameter of 3-7 and 15-20 nm, respectively, and up to 30 mum in length. These nanotubules were not coated by amorphous carbon. Traces of amorphous carbon could be removed by hydrogen. High resolution electron microscopy images and electron diffraction patterns of the straight nanotubules were similar to those obtained by the arc-discharge method. Coiled nanotubules were revealed by TEM to be regular polygonized helices where the bends are caused by pairs of pentagon-heptagon carbon rings among the hexagonal network. |
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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 |
A1994NT08000011 |
Publication Date |
2002-07-25 |
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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 |
0009-2614; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.897 |
Times cited |
405 |
Open Access |
|
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| |
Notes |
|
Approved |
PHYSICS, APPLIED 47/145 Q2 # |
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| |
Call Number |
UA @ lucian @ c:irua:99869 |
Serial |
3595 |
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| Permanent link to this record |
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| |
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Author |
van den Broek, W.; Verbeeck, J.; Schryvers, D.; de Backer, S.; Scheunders, P. |
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| |
Title |
Tomographic spectroscopic imaging; an experimental proof of concept |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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| |
Volume |
109 |
Issue |
4 |
Pages |
296-303 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
Recording the electron energy loss spectroscopy data cube with a series of energy filtered images is a dose inefficient process because the energy slit blocks most of the electrons. When recording the data cube by scanning an electron probe over the sample, perfect dose efficiency is attained; but due to the low current in nanoprobes, this often is slower, with a smaller field of view. In W. Van den Broek et al. [Ultramicroscopy, 106 (2006) 269], we proposed a new method to record the data cube, which is more dose efficient than an energy filtered series. It produces a set of projections of the data cube and then tomographically reconstructs it. In this article, we demonstrate these projections in practice, we present a simple geometrical model that allows for quantification of the projection angles and we present the first successful experimental reconstruction, all on a standard post-column instrument. |
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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 |
000265345400003 |
Publication Date |
2008-12-10 |
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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 |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
1 |
Open Access |
|
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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| |
Call Number |
UA @ lucian @ c:irua:77271 |
Serial |
3671 |
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| Permanent link to this record |
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| |
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Author |
Ramezanipour, F.; Greedan, J.E.; Siewenie, J.; Donaberger, R.L.; Turner, S.; Botton, G.A. |
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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 |
| |
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 |
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 |
|
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 |
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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| |
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Author |
Li, Y.; Tan, H.; Yang, X.-Y.; Goris, B.; Verbeeck, J.; Bals, S.; Colson, P.; Cloots, R.; Van Tendeloo, G.; Su, B.-L. |
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| |
Title |
Well shaped Mn3O4 nano-octahedra with anomalous magnetic behavior and enhanced photodecomposition properties |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Small |
Abbreviated Journal |
Small |
|
| |
Volume |
7 |
Issue |
4 |
Pages |
475-483 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Very uniform and well shaped Mn3O4 nano-octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape-directing agent. The nano-octahedra formation mechanism is monitored. The shape and crystal orientation of the nanoparticles is reconstructed by scanning electron microscopy and electron tomography, which reveals that the nano-octahedra only selectively expose {101} facets at the external surfaces. The magnetic testing demonstrates that the Mn3O4 nano-octahedra exhibit anomalous magnetic properties: the Mn3O4 nano-octahedra around 150 nm show a similar Curie temperature and blocking temperature to Mn3O4 nanoparticles with 10 nm size because of the vertical axis of [001] plane and the exposed {101} facets. With these Mn3O4 nano-octahedra as a catalyst, the photodecomposition of rhodamine B is evaluated and it is found that the photodecomposition activity of Mn3O4 nano-octahedra is much superior to that of commercial Mn3O4 powders. The anomalous magnetic properties and high superior photodecomposition activity of well shaped Mn3O4 nano-octahedra should be related to the special shape of the nanoparticles and the abundantly exposed {101} facets at the external surfaces. Therefore, the shape preference can largely broaden the application of the Mn3O4 nano-octahedra. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000288080400008 |
Publication Date |
2011-01-21 |
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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 |
1613-6810; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
8.643 |
Times cited |
131 |
Open Access |
|
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| |
Notes |
This work was realized in the frame of an Interuniversity Attraction Poles Program (Inanomat-P6/17)-Belgian State-Belgian Science Policy and the project “Redugaz”, financially supported by the European community and the Wallon government in the frame of Interreg IV (France-Wallonie). B. L. S. acknowledges the Chinese Central Government for an “Expert of the State” position in the program of “Thousand talents” and the Chinese Ministry of Education for a Changjiang Scholar position at the Wuhan University of Technology. H. T. acknowledges the financial support from FWO-Vlaanderen (Project nr. G.0147.06). J.V. thanks the financial support from the European Union under Framework 6 program for Integrated Infrastructure Initiative, Reference 026019 ESTEEM. |
Approved |
Most recent IF: 8.643; 2011 IF: 8.349 |
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| |
Call Number |
UA @ lucian @ c:irua:87908 |
Serial |
3914 |
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| Permanent link to this record |
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| |
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Author |
Rizzo, F.; Augieri, A.; Angrisani Armenio, A.; Galluzzi, V.; Mancini, A.; Pinto, V.; Rufoloni, A.; Vannozzi, A.; Bianchetti, M.; Kursumovic, A.; MacManus-Driscoll, J.L.; Meledin, A.; Van Tendeloo, G.; Celentano, G. |
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| |
Title |
Enhanced 77K vortex-pinning in YBa2Cu3O7−x films with Ba2YTaO6 and mixed Ba2YTaO6 + Ba2YNbO6 nano-columnar inclusions with irreversibility field to 11T |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
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| |
Volume |
4 |
Issue |
4 |
Pages |
061101 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Pulsed laser deposited thin YBa2Cu3O7−x (YBCO) films with pinning additions of 5at.% Ba2YTaO6 (BYTO) were compared to films with 2.5at.% Ba2YTaO6 + 2.5at.% Ba2YNbO6 (BYNTO) additions. Excellent magnetic flux-pinning at 77 K was obtained with remarkably high irreversibility fields greater than 10T (YBCO-BYTO) and 11T (YBCO-BYNTO), representing the highest ever achieved values in YBCO films. |
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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 |
000379042400002 |
Publication Date |
2016-06-08 |
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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 |
2166-532X |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.335 |
Times cited |
19 |
Open Access |
|
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| |
Notes |
This work was financially supported by EUROTAPES, a collaborative project funded by the European Commission’s Seventh Framework Program (FP7 / 2007-2013) under Grant Agreement no. 280432 |
Approved |
Most recent IF: 4.335 |
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| |
Call Number |
c:irua:133785 |
Serial |
4077 |
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| Permanent link to this record |
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Author |
Neubert, S.; Mitoraj, D.; Shevlin, S.A.; Pulisova, P.; Heimann, M.; Du, Y.; Goh, G.K.L.; Pacia, M.; Kruczała, K.; Turner, S.; Macyk, W.; Guo, Z.X.; Hocking, R.K.; Beranek, R.; |
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| |
Title |
Highly efficient rutile TiO2 photocatalysts with single Cu(II) and Fe(III) surface catalytic sites |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
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| |
Volume |
4 |
Issue |
4 |
Pages |
3127-3138 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Highly active photocatalysts were obtained by impregnation of nanocrystalline rutile TiO2 powders with small amounts of Cu(II) and Fe(III) ions, resulting in the enhancement of initial rates of photocatalytic degradation of 4-chlorophenol in water by factors of 7 and 4, compared to pristine rutile, respectively. Detailed structural analysis by EPR and X-ray absorption spectroscopy (EXAFS) revealed that Cu(II) and Fe(III) are present as single species on the rutile surface. The mechanism of the photoactivity enhancement was elucidated by a combination of DFT calculations and detailed experimental mechanistic studies including photoluminescence measurements, photocatalytic experiments using scavengers, OH radical detection, and photopotential transient measurements. The results demonstrate that the single Cu(II) and Fe(III) ions act as effective cocatalytic sites, enhancing the charge separation, catalyzing “dark” redox reactions at the interface, thus improving the normally very low quantum yields of UV light-activated TiO2 photocatalysts. The exact mechanism of the photoactivity enhancement differs depending on the nature of the cocatalyst. Cu(II)-decorated samples exhibit fast transfer of photogenerated electrons to Cu(II/I) sites, followed by enhanced catalysis of dioxygen reduction, resulting in improved charge separation and higher photocatalytic degradation rates. At Fe(III)-modified rutile the rate of dioxygen reduction is not improved and the photocatalytic enhancement is attributed to higher production of highly oxidizing hydroxyl radicals produced by alternative oxygen reduction pathways opened by the presence of catalytic Fe(III/II) sites. Importantly, it was demonstrated that excessive heat treatment (at 450 degrees C) of photocatalysts leads to loss of activity due to migration of Cu(II) and Fe(III) ions from TiO2 surface to the bulk, accompanied by formation of oxygen vacancies. The demonstrated variety of mechanisms of photoactivity enhancement at single site catalyst-modified photocatalysts holds promise for developing further tailored photocatalysts for various applications. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000371077300040 |
Publication Date |
2015-12-30 |
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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 |
2050-7488; 2050-7496 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.867 |
Times cited |
44 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 8.867 |
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| |
Call Number |
UA @ lucian @ c:irua:132322 |
Serial |
4191 |
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| Permanent link to this record |
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Author |
Naik, P.V.; Wee, L.H.; Meledina, M.; Turner, S.; Li, Y.; Van Tendeloo, G.; Martens, J.A.; Vankelecom, I.F.J. |
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Title |
PDMS membranes containing ZIF-coated mesoporous silica spheres for efficient ethanol recovery via pervaporation |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Journal of materials chemistry A : materials for energy and sustainability |
Abbreviated Journal |
J Mater Chem A |
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| |
Volume |
4 |
Issue |
4 |
Pages |
12790-12798 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The design of functional micro- and mesostructured composite materials is significantly important for separation processes. Mesoporous silica is an attractive material for fast diffusion, while microporous zeolitic imidazolate frameworks (ZIFs) are beneficial for selective adsorption and diffusion. In this work, ZIF-71 and ZIF-8 nanocrystals were grown on the surface of mesoporous silica spheres (MSS) via the seeding and regrowth approach in order to obtain monodispersed MSS-ZIF-71 and MSS-ZIF-8 spheres with a particle size of 2-3 mm. These MSS-ZIF spheres were uniformly dispersed into a polydimethylsiloxane (PDMS) matrix to prepare mixed matrix membranes (MMMs). These MMMs were evaluated for the separation of ethanol from water via pervaporation. The pervaporation results reveal that the MSS-ZIF filled MMMs substantially improve the ethanol recovery in both aspects viz. flux and separation factor. These MMMs outperforms the unfilled PDMS membranes and the conventional carbon and zeolite filled MMMs. As expected, the mesoporous silica core allows very fast flow of the permeating compound, while the hydrophobic ZIF coating enhances the ethanol selectivity through its specific pore structure, hydrophobicity and surface chemistry. It can be seen that ZIF-8 mainly has a positive impact on the selectivity, while ZIF-71 enhances fluxes more significantly. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000382015100012 |
Publication Date |
2016-07-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2050-7488; 2050-7496 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.867 |
Times cited |
26 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 8.867 |
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Call Number |
UA @ lucian @ c:irua:137188 |
Serial |
4395 |
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| Permanent link to this record |
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Author |
Van Havenbergh, K.; Turner, S.; Marx, N.; Van Tendeloo, G. |
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Title |
The mechanical behavior during (de)lithiation of coated silicon nanoparticles as anode material for lithium-ion batteries studied by InSitu transmission electron microscopy |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Energy technology |
Abbreviated Journal |
Energy Technol-Ger |
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Volume |
4 |
Issue |
4 |
Pages |
1005-1012 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
One approach to cope with the continuous irreversible capacity loss in Si-based electrodes, attributed to lithiation-induced volume changes and the formation of a solid-electrolyte interface (SEI), is by coating silicon nanoparticles. A coating can improve the conductivity of the electrode, form a chemical shield against the electrolyte, or provide mechanical confinement to reduce the volume increase. The influence of such a coating on the mechanical behavior of silicon nanoparticles during Li insertion and Li extraction was investigated by insitu transmission electron microscopy. The type of coating was shown to influence the size of the unreacted core that remains after reaction of silicon with lithium. Furthermore, two mechanisms to relieve the stress generated during volume expansion are reported: the initiation of cracks and the formation of nanovoids. Both result in a full reaction of the silicon nanoparticles, whereas with the formation of cracks, additional surface area is created, on which an SEI can be formed. |
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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 |
000382549500012 |
Publication Date |
2016-06-29 |
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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 |
2194-4296; 2194-4288 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.789 |
Times cited |
6 |
Open Access |
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Notes |
|
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:137167 |
Serial |
4406 |
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| Permanent link to this record |
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Author |
Smolin, S.Y.; Choquette, A.K.; Wilks, R.G.; Gauquelin, N.; Félix, R.; Gerlach, D.; Ueda, S.; Krick, A.L.; Verbeeck, J.; Bär, M.; Baxter, J.B.; May, S.J. |
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Title |
Energy Level Alignment and Cation Charge States at the LaFeO3/LaMnO3(001) Heterointerface |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
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| |
Volume |
4 |
Issue |
4 |
Pages |
1700183 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The electronic properties of LaFeO 3 /LaMnO 3 epitaxial heterojunctions are investigated to determine the valence and conduction band offsets and the nominal Mn and Fe valence states at the interface. Studying a systematic series of (LaFeO 3 ) n /(LaMnO 3 ) m bilayers (m ≈ 50) epitaxially grown in the (001) orientation using molecular beam epitaxy, layer-resolved electron energy loss spectroscopy reveals a lack of significant interfacial charge transfer, with a nominal 3+ valence state observed for both Mn and Fe across the interface. Through a combination of variable angle spectroscopic ellipsometry and hard X-ray photoelectron spectroscopy, type I energy level alignments are obtained at the LaFeO 3 /LaMnO 3 interface with positive valence and conduction band offsets of (1.20 ± 0.07) eV and (0.5–0.7 ± 0.3) eV, respectively, with minimal band bending. Variable temperature resistivity measurements reveal that the bilayers remain insulating and that the presence of the heterojunction does not result in a conducting interface. |
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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 |
000406068400011 |
Publication Date |
2017-04-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.279 |
Times cited |
14 |
Open Access |
Not_Open_Access |
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| |
Notes |
The authors thank Dmytro Nykypanchuk for assistance with the near- infrared ellipsometry measurement of the LaMnO 3 film. S.Y.S., A.K.C., J.B.B, and S.J.M. acknowledge funding from the National Science Foundation under grant number ECCS-1201957. S.Y.S. acknowledges additional funding from the German Academic Exchange Service (DAAD) through the Research Internships in Science and Engineering (RISE) professional program 2015 ID 5708457. A.L.K. was funded by the National Science Foundation under grant number DMR-1151649. J.V. and N.G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge ordering). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. Ellipsometry measurements of the LaMnO 3 film were carried out at the Center for Functional Nanomaterials, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-ACO2-98CH10886. S.U. would like to thank the staff of HiSOR, Hiroshima University, and JAEA/Spring-8 for the development of HAXPES at BL15XU of SPring-8. The HAXPES measurements were performed with approval of NIMS Synchrotron X-ray Station (Proposal No. 2015B4601), and were partly supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. The authors also thank HZB for the allocation of synchrotron radiation beamtime for HAXPES/XANES measurements. R.G.W., R.F, and M.B. are grateful to the Impuls- und Vernetzungsfonds of the Helmholtz Association (VH-NG-423).; National Science Foundation, ECCS-1201957 DMR-1151649 ; Deutscher Akademischer Austauschdienst, 2015 ID 5708457 ; GOA project; Fonds Wetenschappelijk Onderzoek, G.0044.13N ; Flemish Government; U.S. Department of Energy, DE-ACO2-98CH10886 ; Vernetzungsfonds of the Helmholtz Association, VH-NG-423 ; |
Approved |
Most recent IF: 4.279 |
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Call Number |
EMAT @ emat @ c:irua:142346UA @ admin @ c:irua:142346 |
Serial |
4553 |
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| Permanent link to this record |
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Author |
Lander, L.; Rousse, G.; Batuk, D.; Colin, C.V.; Dalla Corte, D.A.; Tarascon, J.-M. |
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Title |
Synthesis, structure, and electrochemical properties of k-based sulfates K2M2(SO4)3) with M = Fe and Cu |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
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| |
Volume |
56 |
Issue |
4 |
Pages |
2013-2021 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Stabilizing new host structures through potassium extraction from K-based polyanionic materials has been proven to be an interesting approach to develop new Li+/Na+ insertion materials. Pursuing the same trend, we here report the feasibility of preparing langbeinite “Fe-2(SO4)(3)” via electrochemical and chemical oxidation of K2Fe2(SO4)(3). Additionally, we succeeded in stabilizing a new K2Cu2(SO4)(3) phase via a solid-state synthesis approach. This novel compound crystallizes in a complex orthorhombic structure that differs from that of langbeinite as deduced from synchrotron X-ray and neutron powder diffraction. Electrochemically, the performance of this new phase is limited, which we explain in terms of sluggish diffusion kinetics. We further show that K2Cu2(SO4)(3) decomposes into K2Cu3O(SO4)(3) on heating, and we report for the first time the synthesis of fedotovite K2Cu3O(SO4)(3). Finally, the fundamental attractiveness of these S = 1/2 systems for physicists is examined by neutron magnetic diffraction, which reveals the absence of a long-range ordering of Cu2+ magnetic moments down to 1.5 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 |
Easton, Pa |
Editor |
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Language |
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Wos |
000394736600027 |
Publication Date |
2017-01-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0020-1669 |
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 |
Not_Open_Access |
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Notes |
; We thank Matthieu Courty for performing TGA/DSC measurements. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the U.S. Department of Energy under Contract DE-AC02-06CH11357 and is acknowledged. The French CRG D1B is acknowledged for allocating neutron beamtime. L.L. thanks the ANR “Hipolite” for the Ph.D. funding. ; |
Approved |
Most recent IF: 4.857 |
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| |
Call Number |
UA @ lucian @ c:irua:142531 |
Serial |
4692 |
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| Permanent link to this record |
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Author |
Sieger, M.; Pahlke, P.; Lao, M.; Eisterer, M.; Meledin, A.; Van Tendeloo, G.; Ottolinger, R.; Haenisch, J.; Holzapfel, B.; Usoskin, A.; Kursumovic, A.; MacManus-Driscoll, J.L.; Stafford, B.H.; Bauer, M.; Nielsch, K.; Schultz, L.; Huehne, R. |
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Title |
Tailoring microstructure and superconducting properties in thick BaHfO3 and Ba2YNb/Ta)O-6 doped YBCO films on technical templates |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
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| |
Volume |
27 |
Issue |
4 |
Pages |
6601407 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
The current transport capability of YBa2Cu3O7-x(YBCO) based coated conductors (CCs) is mainly limited by two features: the grain boundaries of the used textured template, which are transferred into the superconducting film through the buffer layers, and the ability to pin magnetic flux lines by incorporation of defined defects in the crystal lattice. By adjusting the deposition conditions, it is possible to tailor the pinning landscape in doped YBCO in order to meet specific working conditions (T, B) for CC applications. To study these effects, we deposited YBCO layers with a thickness of about 1-2 mu m using pulsed laser deposition on buffered rolling-assisted biaxially textured Ni-W substrates as well as on metal tapes having either an ion-beam-texturedYSZbuffer or an MgO layer textured by inclined substrate deposition. BaHfO3 and the mixed double-perovskite Ba2Y(Nb/Ta)O-6 were incorporated as artificial pinning centers in these YBCO layers. X-ray diffraction confirmed the epitaxial growth of the superconductor on these templates as well as the biaxially oriented incorporation of the secondary phase additions in the YBCO matrix. A critical current density J(c) of more than 2 MA/cm(2) was achieved at 77 K in self-field for 1-2 mu m thick films. Detailed TEM (transmission electron microscopy) studies revealed that the structure of the secondary phase can be tuned, forming c-axis aligned nanocolumns, ab-oriented platelets, or a combination of both. Transport measurements show that the J(c) anisotropy in magnetic fields is reduced by doping and the peak in the J(c) (theta) curves can be correlated to the microstructural features. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000394588100001 |
Publication Date |
2016-12-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
1051-8223 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
12 |
Open Access |
OpenAccess |
|
| |
Notes |
; This work was supported by EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7/2007-2013) under Grant Agreement no. 280432. ; |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:141961 |
Serial |
4693 |
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| Permanent link to this record |
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Author |
Ata, I.; Ben Dkhil, S.; Pfannmoeller, M.; Bals, S.; Duche, D.; Simon, J.-J.; Koganezawa, T.; Yoshimoto, N.; Videlot-Ackermann, C.; Margeat, O.; Ackermann, J.; Baeuerle, P. |
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| |
Title |
The influence of branched alkyl side chains in A-D-A oligothiophenes on the photovoltaic performance and morphology of solution-processed bulk-heterojunction solar cells |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Organic chemistry frontiers : an international journal of organic chemistry |
Abbreviated Journal |
Org Chem Front |
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| |
Volume |
4 |
Issue |
4 |
Pages |
1561-1573 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Besides providing sufficient solubility, branched alkyl chains also affect the film-forming and packing properties of organic semiconductors. In order to avoid steric hindrance as it is present in wide-spread alkyl chains comprising a branching point position at the C2-position, i.e., 2-ethylhexyl, the branching point can be moved away from the pi-conjugated backbone. In this report, we study the influence of the modification of the branching point position from the C2-position in 2-hexyldecylamine (1) to the C4-position in 4-hexyldecylamine (2) connected to the central dithieno[3,2-b: 2', 3'-d] pyrrole (DTP) moiety in a well-studied A-D-A oligothiophene on the optoelectronic properties and photovoltaic performance in solution- processed bulk heterojunction solar cells (BHJSCs) with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor material. Post-treatment of the photoactive layers is performed via solvent vapor annealing (SVA) in order to improve the film microstructure of the bulk heterojunction. The time evolution of nanoscale morphological changes is followed by combining scanning transmission electron microscopy with low-energy-loss spectroscopic imaging (STEM-SI), solid-state absorption spectroscopy, and two-dimensional grazing incidence X-ray diffraction (2D-GIXRD). Our results show an improvement of the photovoltaic performance that is dependent on the branching point position in the donor oligomer. Optical spacers are utilized to increase light absorption inside the co-oligomer 2-based BHJSCs leading to increased power conversion efficiencies (PCEs) of 8.2% when compared to the corresponding co-oligomer 1-based devices. A STEM-SI analysis of the respective device cross-sections of active layers containing 1 and 2 as donor materials indeed reveals significant differences in their respective active layer morphologies. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
RSC Publishing |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000406374800013 |
Publication Date |
2017-05-02 |
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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 |
2052-4129 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.955 |
Times cited |
24 |
Open Access |
OpenAccess |
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| |
Notes |
; We acknowledge financial support by the European Commission under the project “SUNFLOWER” (FP7-ICT-2011-7, grant number: 287594) and S.B. acknowledges the ERC Starting Grant Colouratoms (335078). ; |
Approved |
Most recent IF: 4.955 |
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| |
Call Number |
UA @ lucian @ c:irua:145176UA @ admin @ c:irua:145176 |
Serial |
4727 |
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| Permanent link to this record |
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Author |
Zhou, Y.; Ramaneti, R.; Anaya, J.; Korneychuk, S.; Derluyn, J.; Sun, H.; Pomeroy, J.; Verbeeck, J.; Haenen, K.; Kuball, M. |
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Title |
Thermal characterization of polycrystalline diamond thin film heat spreaders grown on GaN HEMTs |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
| |
Volume |
111 |
Issue |
4 |
Pages |
041901 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Polycrystalline diamond (PCD) was grown onto high-k dielectric passivated AlGaN/GaN-on-Si high electron mobility transistor (HEMT) structures, with film thicknesses ranging from 155 to 1000 nm. Transient thermoreflectance results were combined with device thermal simulations to investigate the heat spreading benefit of the diamond layer. The observed thermal conductivity (k(Dia)) of PCD films is one-to-two orders of magnitude lower than that of bulk PCD and exhibits a strong layer thickness dependence, which is attributed to the grain size evolution. The films exhibit a weak temperature dependence of k(Dia) in the measured 25-225 degrees C range. Device simulation using the experimental jDia and thermal boundary resistance values predicts at best a 15% reduction in peak temperature when the source-drain opening of a passivated AlGaN/GaN-on-Si HEMT is overgrown with PCD. Published by AIP Publishing. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000406779700008 |
Publication Date |
2017-07-24 |
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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 |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.411 |
Times cited |
78 |
Open Access |
Not_Open_Access |
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| |
Notes |
; The authors are grateful to Professor Michael Uren and Dr. Roland B. Simon (University of Bristol) for helpful discussions and to Dr. Sien Drijkoningen (Hasselt University) for taking the SEM micrographs. This work was in part supported by DARPA under Contract No. FA8650-15-C-7517, monitored by Dr. Avram Bar Cohen and Dr. John Blevins, and supported by Dr. Joseph Maurer and Dr. Abirami Sivananthan. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of DARPA. Y.Z. acknowledges China Scholarship Council for the financial support. S.K. and J.V. acknowledge the FWO-Vlaanderen for financial support under contract G.0044.13N “Charge ordering.” ; |
Approved |
Most recent IF: 3.411 |
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| |
Call Number |
UA @ lucian @ c:irua:145203 |
Serial |
4728 |
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| Permanent link to this record |
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Author |
Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Altantzis, T.; Sada, C.; Kaunisto, K.; Ruoko, T.-P.; Bals, S. |
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Title |
Vapor Phase Fabrication of Nanoheterostructures Based on ZnO for Photoelectrochemical Water Splitting |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
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| |
Volume |
4 |
Issue |
4 |
Pages |
1700161 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Nanoheterostructures based on metal oxide semiconductors have emerged
as promising materials for the conversion of sunlight into chemical energy.
In the present study, ZnO-based nanocomposites have been developed by
a hybrid vapor phase route, consisting in the chemical vapor deposition
of ZnO systems on fluorine-doped tin oxide substrates, followed by the
functionalization with Fe2O3 or WO3 via radio frequency-sputtering. The
target systems are subjected to thermal treatment in air both prior and after
sputtering, and their properties, including structure, chemical composition,
morphology, and optical absorption, are investigated by a variety of characterization
methods. The obtained results evidence the formation of highly
porous ZnO nanocrystal arrays, conformally covered by an ultrathin Fe2O3
or WO3 overlayer. Photocurrent density measurements for solar-triggered
water splitting reveal in both cases a performance improvement with respect
to bare zinc oxide, that is mainly traced back to an enhanced separation of
photogenerated charge carriers thanks to the intimate contact between the
two oxides. This achievement can be regarded as a valuable result in view of
future optimization of similar nanoheterostructured photoanodes. |
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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 |
000411525700007 |
Publication Date |
2017-05-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.279 |
Times cited |
30 |
Open Access |
OpenAccess |
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| |
Notes |
The authors kindly acknowledge the financial support under Padova University ex-60% 2013–2016, P-DiSC #SENSATIONAL BIRD2016- UNIPD projects and the post-doc fellowship ACTION. S.B. acknowledges financial support from the European Research Council (Starting Grant No. COLOURATOM 335078) and T.A. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) through a postdoctoral grant. Many thanks are also due to Dr. Rosa Calabrese (Department of Chemistry, Padova University, Italy) for experimental assistance. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); saraecas; ECAS_Sara; |
Approved |
Most recent IF: 4.279 |
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Call Number |
EMAT @ emat @c:irua:146104UA @ admin @ c:irua:146104 |
Serial |
4731 |
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| Permanent link to this record |
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Author |
Niu, H.; Pitcher, M.J.; Corkett, A.J.; Ling, S.; Mandal, P.; Zanella, M.; Dawson, K.; Stamenov, P.; Batuk, D.; Abakumov, A.M.; Bull, C.L.; Smith, R.I.; Murray, C.A.; Day, S.J.; Slater, B.; Cora, F.; Claridge, J.B.; Rosseinsky, M.J. |
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Title |
Room Temperature Magnetically Ordered Polar Corundum GaFeO3 Displaying Magnetoelectric Coupling |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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| |
Volume |
139 |
Issue |
4 |
Pages |
1520-1531 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The polar corundum structure type offers a route to new room temperature multiferroic materials, as the partial LiNbO3-type cation ordering that breaks inversion symmetry may be combined with long-range magnetic ordering of high spin d(5) cations above room temperature in the AFeO(3) system. We report the synthesis of a polar corundum GaFeO3 by a high-pressure, high-temperature route and demonstrate that its polarity arises from partial LiNbO3 -type cation ordering by complementary use of neutron, X-ray, and electron diffraction methods. In situ neutron diffraction shows that the polar corundum forms directly from AlFeO3-type GaFeO3 under the synthesis conditions. The A(3+)/Fe3+ cations are shown to be more ordered in polar corundum GaFeO3 than in isostructural ScFeO3. This is explained by DFT calculations which indicate that the extent of ordering is dependent on the configurational entropy available to each system at the very different synthesis temperatures required to form their corundum structures. Polar corundum GaFeO3 exhibits weak ferromagnetism at room temperature that arises from its Fe2O3-like magnetic ordering, which persists to a temperature of 408 K. We demonstrate that the polarity and magnetization are coupled in this system with a measured linear magnetoelectric coupling coefficient of 0.057 ps/m. Such coupling is a prerequisite for potential applications of polar corundum materials in multiferroic/magnetoelectric devices. |
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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 |
000393355600034 |
Publication Date |
2016-12-25 |
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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 |
0002-7863 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.858 |
Times cited |
12 |
Open Access |
OpenAccess |
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Notes |
This work was funded by the EPSRC under EP/N004884. We thank the STFC for provision of beam time at ISIS and Diamond Light Source. We thank the Materials Chemistry Consortium (EPSRC, EP/L000202) for access to computer time on the ARCHER UK National Supercomputing Service (http://www.archer.ac.uk). A.M.A. is grateful to the Russian Science Foundation (Grant 14-13-00680) for financial support. MJ.R is a Royal Society Research Professor. We wish to thank Dr. Ming Li (University of Nottingham, UK) for helpful discussion and advice. Original data is available at the University of Liverpool's DataCat repository at DOI: 10.17638/datacat.liverpool.ac.uk/235. The supporting crystallographic information file may also be obtained from FIZ Karlsruhe, 76344 Eggenstein-Leopoldshafen, Germany (e-mail: crysdata@fiz-karlsruhe.de), on quoting the deposition number CSD-432419. |
Approved |
Most recent IF: 13.858 |
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Call Number |
EMAT @ emat @c:irua:147507 |
Serial |
4777 |
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| Permanent link to this record |
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Author |
Song, H.-D.; Wu, Y.-F.; Yang, X.; Ren, Z.; Ke, X.; Kurttepeli, M.; Tendeloo, G.V.; Liu, D.; Wu, H.-C.; Yan, B.; Wu, X.; Duan, C.-G.; Han, G.; Liao, Z.-M.; Yu, D. |
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Title |
Asymmetric Modulation on Exchange Field in a Graphene/BiFeO3Heterostructure by External Magnetic Field |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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| |
Volume |
18 |
Issue |
4 |
Pages |
2435-2441 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
Graphene, having all atoms on its surface, is favorable to extend the functions by introducing the spin–orbit coupling and magnetism through proximity effect. Here, we report the tunable interfacial exchange field produced by proximity coupling in graphene/BiFeO3 heterostructures. The exchange field has a notable dependence with external magnetic field, and it is much larger under negative magnetic field than that under positive magnetic field. For negative external magnetic field, interfacial exchange coupling gives rise to evident spin splitting for N ≠ 0 Landau levels and a quantum Hall metal state for N = 0 Landau level. Our findings suggest graphene/BiFeO3 heterostructures are promising for spintronics. |
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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 |
000430155900034 |
Publication Date |
2018-04-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1530-6984 |
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 |
9 |
Open Access |
Not_Open_Access |
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Notes |
This work was supported by National Key Research and Development Program of China (No. 2016YFA0300802) and NSFC (Nos. 11774004 and 11604004). Ministry of Science and Technology of the People's Republic of China, 2016YFA0300802 ; National Natural Science Foundation of China, 11604004 11774004 ; |
Approved |
Most recent IF: 12.712 |
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Call Number |
EMAT @ lucian @c:irua:150794 |
Serial |
4923 |
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Author |
Lutz, L.; Corte, D.A.D.; Chen, Y.; Batuk, D.; Johnson, L.R.; Abakumov, A.; Yate, L.; Azaceta, E.; Bruce, P.G.; Tarascon, J.-M.; Grimaud, A. |
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Title |
The role of the electrode surface in Na-Air batteries : insights in electrochemical product formation and chemical growth of NaO2 |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Advanced energy materials |
Abbreviated Journal |
Adv Energy Mater |
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Volume |
8 |
Issue |
4 |
Pages |
1701581 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The Na-air battery, because of its high energy density and low charging overpotential, is a promising candidate for low-cost energy storage, hence leading to intensive research. However, to achieve such a battery, the role of the positive electrode material in the discharge process must be understood. This issue is herein addressed by exploring the electrochemical reduction of oxygen, as well as the chemical formation and precipitation of NaO2 using different electrodes. Whereas a minor influence of the electrode surface is demonstrated on the electrochemical formation of NaO2, a strong dependence of the subsequent chemical precipitation of NaO2 is identified. In the origin, this effect stems from the surface energy and O-2/O-2(-) affinity of the electrode. The strong interaction of Au with O-2/O-2(-) increases the nucleation rate and leads to an altered growth process when compared to C surfaces. Consequently, thin (3 mu m) flakes of NaO2 are found on Au, whereas on C large cubes (10 mu m) of NaO2 are formed. This has significant impact on the cell performance and leads to four times higher capacity when C electrodes with low surface energy and O-2/O-2(-) affinity are used. It is hoped that these findings will enable the design of new positive electrode materials with optimized surfaces. |
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Publisher |
WILEY-VCH Verlag GmbH & Co. |
Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000424152200009 |
Publication Date |
2017-09-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1614-6832; 1614-6840 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
16.721 |
Times cited |
13 |
Open Access |
Not_Open_Access |
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Notes |
; L.L. thanks ALISTORE-ERI for his PhD grant. P.G.B. is indebted to the EPSRC for financial support, including the Supergen Energy Storage grant. ; |
Approved |
Most recent IF: 16.721 |
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Call Number |
UA @ lucian @ c:irua:149269 |
Serial |
4951 |
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Author |
Roxana Vlad, V.; Bartolome, E.; Vilardell, M.; Calleja, A.; Meledin, A.; Obradors, X.; Puig, T.; Ricart, S.; Van Tendeloo, G.; Usoskin, A.; Lee, S.; Petrykin, V.; Molodyk, A. |
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Title |
Inkjet printing multideposited YBCO on CGO/LMO/MgO/Y2O3/Al2O3/Hastelloy tape for 2G-coated conductors |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
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| |
Volume |
28 |
Issue |
4 |
Pages |
6601805 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We present the preparation of a new architecture of coated conductor by Inkjet printing of low fluorine YBa2Cu3O7-x (YBCO) on top of SuperOx tape: CGO/LMO/IBAD-MgO/Y2O3/Al-2 O-3/Hastelloy. A five-layered multideposited, 475-nm-thick YBCO film was structurally and magnetically characterized. A good texture was achieved using this combination of buffer layers, requiring only a 30-nm-thin ion-beam-assisted deposition (IBAD)-MgO layer. The LF-YBCO CC reaches self-field critical current density values of J(c)(GB) similar to NJ 15.9 MA/cm(2) (5 K), similar to 1.23 MA/cm(2) (77 K) corresponding to an I-c (77 K) = 58.4 A/cm-width. Inkjet printing offers a flexible and cost effective method for YBCO deposition, allowing patterning of 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 |
New York, N.Y. |
Editor |
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Language |
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Wos |
000429010900001 |
Publication Date |
2018-02-22 |
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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 |
1051-8223 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.288 |
Times cited |
2 |
Open Access |
Not_Open_Access |
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Notes |
; This work was performed within the framework of the EUROTAPES Project FP7-NMP.2011.2.2-1 under Grant280432, funded by the EU. ICMAB research was financed by the Ministry of Economy and Competitiveness, and FEDER funds under Projects MAT2011-28874-C02-01, MAT2014-51778-C2-1-R, ENE2014-56109-C3-3-R, and Consolider Nanoselect CSD2007-00041, and by Generalitat de Catalunya (2009 SGR 770, 2015 SGR 753, and Xarmae). ICMAB acknowledges support from Severo Ochoa Program (MINECO) under Grant SEV-2015-0496. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:150711 |
Serial |
4971 |
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| Permanent link to this record |
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Author |
Sieger, M.; Pahlke, P.; Lao, M.; Meledin, A.; Eisterer, M.; Van Tendeloo, G.; Schultz, L.; Nielsch, K.; Huehne, R. |
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Title |
Thick secondary phase pinning-enhanced YBCO films on technical templates |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
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| |
Volume |
28 |
Issue |
4 |
Pages |
8000505 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The critical current I-c(B) of YBa2Cu3O7-delta (YBCO) coated conductors can be increased by growing thicker superconductor layers as well as improving the critical current density J(c)(B) by the incorporation of artificial pinning centers. We studied the properties of pulsed laser deposited BaHfO3 (BHO)-doped YBCO films with thicknesses of up to 5 mu m on buffered rolling-assisted biaxially textured Ni-5 at % W tape and alternating beam assisted deposition textured Yttrium-stabilized ZrO2 layers on stainless steel. X-Ray diffraction confirms the epitaxial growth of the superconductor on the buffered metallic template. BHO additions reduce the film porosity and lower the probability to grow misoriented grains, hence preventing the J(c) decrease observed in undoped YBCO films with thicknesses > 2 mu m. Thereby, a continuous increase in I-c at 77 K is achieved. A mixed structure of secondary phase nanorods and platelets with different orientations increases J(c)(B) in the full angular range and simultaneously lowers the J(c) anisotropy compared to pristine YBCO. |
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Place of Publication |
New York, N.Y. |
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Wos |
000427623700001 |
Publication Date |
2018-01-30 |
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ISSN |
1051-8223 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.288 |
Times cited |
1 |
Open Access |
Not_Open_Access |
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Notes |
; This work was supported by EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7 / 2007 – 2013) under Grant Agreement no. 280432. Max Sieger acknowledges funding by the Graduate Academy of the Technical University Dresden, funded by means of the Excellence Initiative by the German Federal and State Governments. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:150712 |
Serial |
4986 |
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Author |
Pahlke, P.; Sieger, M.; Ottolinger, R.; Lao, M.; Eisterer, M.; Meledin, A.; Van Tendeloo, G.; Haenisch, J.; Holzapfel, B.; Schultz, L.; Nielsch, K.; Huehne, R. |
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Title |
Influence of artificial pinning centers on structural and superconducting properties of thick YBCO films on ABAD-YSZ templates |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
31 |
Issue |
4 |
Pages |
044007 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Recent efforts in the development of YBa2Cu3O7-x (YBCO) coated conductors are devoted to the increase of the critical current I-c in magnetic fields. This is typically realized by growing thicker YBCO layers as well as by the incorporation of artificial pinning centers. We studied the growth of doped YBCO layers with a thickness of up to 7 mu m using pulsed laser deposition with a growth rate of about 1.2 nm s(-1). Industrially fabricated ion-beam textured YSZ templates based on metal tapes were used as substrates for this study. The incorporation of BaHfO3 (BHO) or Ba2Y(Nb0.5Ta0.5)O-6 (BYNTO) secondary phase additions leads to a denser microstructure compared to undoped films. A purely c-axis-oriented YBCO growth is preserved up to a thickness of about 4 mu m, whereas misoriented texture components were observed in thicker films. The critical temperature is slightly reduced compared to undoped films and independent of film thickness. The critical current density J(c) of the BHO- and BYNTO-doped YBCO layers is lower at 77 K and self-field compared to pure YBCO layers; however, I-c increases up to a thickness of 5 mu m. A comparison between films with a thickness of 1.3 mu m revealed that the anisotropy of the critical current density J(c)(theta) strongly depends on the incorporated pinning centers. Whereas BHO nanorods lead to a strong B vertical bar vertical bar c-axis peak, the overall anisotropy is significantly reduced by the incorporation of BYNTO forming a mixture of short c-axis-oriented nanorods and small (a-b)-oriented platelets. As a result, the J(c) values of the doped films outperform the undoped samples at higher fields and lower temperatures for most magnetic field directions. |
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Place of Publication |
Bristol |
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Wos |
000442196400001 |
Publication Date |
2018-02-15 |
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ISSN |
0953-2048 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.878 |
Times cited |
9 |
Open Access |
OpenAccess |
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Notes |
; The authors acknowledge financial support from EURO-TAPES, a collaborative project funded by the European Union's Seventh Framework Programme (FP7/ 2007-2013) under Grant Agreement no. 280432. We thank A Usoskin (Bruker HTS GmbH, Germany) for the provision of buffered templates, and M Bianchetti, A Kursumovic and J L Mac-Manus-Driscoll (University of Cambridge, UK) for the supply of BYNTO targets. The authors also gratefully acknowledge the technical assistance of J Scheiter, M Kuhnel, U Besold (IFW) and R Nast (KIT). ; |
Approved |
Most recent IF: 2.878 |
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Call Number |
UA @ lucian @ c:irua:153775 |
Serial |
5108 |
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Author |
Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J. |
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Title |
Interstitial defects in the van der Waals gap of Bi2Se3 |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) |
Abbreviated Journal |
Acta Crystallogr B |
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Volume |
75 |
Issue |
4 |
Pages |
717-732 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Bi<sub>2</sub>Se<sub>3</sub>is a thermoelectric material and a topological insulator. It is slightly conducting in its bulk due to the presence of defects and by controlling the defects different physical properties can be fine tuned. However, studies of the defects in this material are often contradicting or inconclusive. Here, the defect structure of Bi<sub>2</sub>Se<sub>3</sub>is studied with a combination of techniques: high-resolution scanning transmission electron microscopy (HR-STEM), high-resolution energy-dispersive X-ray (HR-EDX) spectroscopy, precession electron diffraction tomography (PEDT), X-ray diffraction (XRD) and first-principles calculations using density functional theory (DFT). Based on these results, not only the observed defects are discussed, but also the discrepancies in results or possibilities across the techniques. STEM and EDX revealed interstitial defects with mainly Bi character in an octahedral coordination in the van der Waals gap, independent of the applied sample preparation method (focused ion beam milling or cryo-crushing). The inherent character of these defects is supported by their observation in the structure refinement of the EDT data. Moreover, the occupancy probability of the defects determined by EDT is inversely proportional to their corresponding DFT calculated formation energies. STEM also showed the migration of some atoms across and along the van der Waals gap. The kinetic barriers calculated using DFT suggest that some paths are possible at room temperature, while others are most probably beam induced. |
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Wos |
000480512600024 |
Publication Date |
2019-08-01 |
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ISSN |
2052-5206 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.032 |
Times cited |
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Notes |
University of Antwerp, 31445 ; Acknowledgements We thank Artem M. Abakumov for providing the original Bi2Se3 sample and are also very grateful to Christophe Vandevelde for trying repeatedly to get good single crystal X-ray diffraction data out of each of our failed attempts at making an undeformed single crystal. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. |
Approved |
Most recent IF: 2.032 |
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Call Number |
EMAT @ emat @c:irua:161847 |
Serial |
5295 |
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