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Records |
Links |
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Author |
Kips, R.; Pidduck, A.J.; Houlton, M.R.; Leenaers, A.; Mace, J.D.; Marie, O.; Pointurier, F.; Stefaniak, E.A.; Taylor, P.D.P.; van den Berghe, S.; van Espen, P.; Van Grieken, R.; Wellum, R. |
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Title |
Determination of fluorine in uranium oxyfluoride particles as an indicator of particle age |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
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| |
Volume |
64 |
Issue |
3 |
Pages |
199-207 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3) |
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Abstract |
As swipe samples from enrichment activities typically contain uranium particles with a detectable amount of fluorine, the question was raised whether the analysis of fluorine in particles could complement the information on the uranium isotope ratios. For this, uranium oxyfluoride particles were prepared from the controlled hydrolysis of uranium hexafluoride (UF6). The relative amount of fluorine was characterized by scanning electron microscopy combined with energy-dispersive X-ray spectrometry (SEM-EDX), as well as ion-microprobe secondary ion mass spectrometry (IM-SIMS). Of particular interest was the assessment of the reduction of the amount of fluorine over time, and after exposure to UV-light and high temperatures. Micro-Raman spectrometry (MRS) was applied to look for differences in molecular structure between these various sample types. Both SEM-EDX and IM-SIMS showed a general reduction of the fluorine-to-uranium ratio after 12 years of storage. The exposure to UV-light and high temperatures was found to have accelerated the loss of fluorine. A distinct peak at 865 cm− 1 Raman shift was detected for the majority of particles analyzed by MRS. For the particles that were heat-treated, the Raman spectra were similar to the spectrum of U3O8. Although often large variations were observed between particles from the same sample, the three particle measurement techniques (IM-SIMS, SEM-EDX and MRS) showed some consistent trends. They therefore appear promising in terms of the ability to place bounds on particle age, as well as shedding light on the complex processes involved in UO2F2 particle ageing. |
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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 |
000265755600002 |
Publication Date |
2008-12-25 |
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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 |
0584-8547; 1873-3565 |
ISBN |
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Additional Links  |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:77057 |
Serial |
7780 |
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| Permanent link to this record |
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Author |
Hadermann, J.; Abakumov, A.M.; Van Rompaey, S.; Mankevich, A.S.; Korsakov, I.E. |
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Title |
Comment on ALaMn2O6-y (A = K, Rb): novel ferromagnetic manganites exhibiting negative giant magnetoresistance |
Type |
Editorial |
| |
Year |
2009 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
21 |
Issue |
9 |
Pages |
2000-2001 |
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| |
Keywords |
Editorial; 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 |
Washington, D.C. |
Editor |
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Language |
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Wos |
000265781000036 |
Publication Date |
2009-04-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
4 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
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| |
Call Number |
UA @ lucian @ c:irua:77055 |
Serial |
411 |
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| Permanent link to this record |
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Author |
Dubourdieu, C.; Rauwel, E.; Roussel, H.; Ducroquet, F.; Hollaender, B.; Rossell, M.; Van Tendeloo, G.; Lhostis, S.; Rushworth, S. |
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Title |
Addition of yttrium into HfO2 films: microstructure and electrical properties |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of vacuum science and technology: A: vacuum surfaces and films |
Abbreviated Journal |
J Vac Sci Technol A |
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| |
Volume |
27 |
Issue |
3 |
Pages |
503-514 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The cubic phase of HfO2 was stabilized by addition of yttrium in thin films grown on Si/SiO2 by metal-organic chemical vapor deposition. The cubic phase was obtained for contents of 6.5 at. % Y or higher at a temperature as low as 470 °C. The complete compositional range (from 1.5 to 99.5 at. % Y) was investigated. The crystalline structure of HfO2 was determined from x-ray diffraction, electron diffraction, and attenuated total-reflection infrared spectroscopy. For cubic films, the continuous increase in the lattice parameter indicates the formation of a solid-solution HfO2Y2O3. As shown by x-ray photoelectron spectroscopy, yttrium silicate is formed at the interface with silicon; the interfacial layer thickness increases with increasing yttrium content and increasing film thickness. The dependence of the intrinsic relative permittivity r as a function of Y content was determined. It exhibits a maximum of ~30 for ~8.8 at. % Y. The cubic phase is stable upon postdeposition high-temperature annealing at 900 °C under NH3. |
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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 |
000265739100016 |
Publication Date |
2009-05-02 |
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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 |
0734-2101; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.374 |
Times cited |
29 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 1.374; 2009 IF: 1.297 |
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Call Number |
UA @ lucian @ c:irua:77054 |
Serial |
58 |
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| Permanent link to this record |
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Author |
Barreca, D.; Gasparotto, A.; Maccato, C.; Tondello, E.; Lebedev, O.I.; Van Tendeloo, G. |
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Title |
CVD of copper oxides from a \beta-diketonate diamine precursor: tailoring the nano-organization |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
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Volume |
9 |
Issue |
5 |
Pages |
2470-2480 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A copper(II) hexafluoroacetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate, hfa) adduct with N,N,N¡ä,N¡ä-tetramethylethylenediamine (TMEDA) [Cu(hfa)2¡¤TMEDA] is used for the first time as precursor for the chemical vapor deposition (CVD) of copper oxide nanosystems. The syntheses are carried out under both O2 and O2+H2O reaction atmospheres on Si(100) substrates, at temperatures ranging between 250 and 550 ¡ãC. Subsequently, the interrelations between the preparative conditions and the system composition, nanostructure, and morphology are elucidated by means of complementary analytical techniques [Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron and X-ray excited auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM)]. The obtained data revealed a gradual transformation from Cu2O, to Cu2O + CuO, to CuO nanosystems upon increasing the deposition temperature from 250 to 550 ¡ãC under both growth atmospheres. Such a phenomenon was accompanied by a progressive morphological evolution from continuous films to 1D hyperbranched nanostructures. Water vapor introduction in the deposition environment enabled to lower the deposition temperature and resulted in a higher aggregate interconnection, attributed to a higher density of nucleation centers. |
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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 |
000265892200066 |
Publication Date |
2009-05-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1528-7483;1528-7505; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.055 |
Times cited |
60 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
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Call Number |
UA @ lucian @ c:irua:77053 |
Serial |
597 |
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| Permanent link to this record |
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Author |
Bharathy, M.; Gemmill, W.R.; Fox, A.H.; Darriet, J.; Smith, M.D.; Hadermann, J.; Remy, M.S.; zur Loye, H.-C. |
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Title |
Synthesis and magnetic properties of rare earth ruthenates, Ln5Ru2O12 (Ln=Pr, Nd, SmTb) |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
182 |
Issue |
5 |
Pages |
1164-1170 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Single crystals of Ln5Ru2O12 (Ln=Pr, Nd, SmTb) were grown out of either NaOH or KOH fluxes in sealed silver tubes. The crystals of all the phases were observed to be twinned as confirmed by TEM studies. The series crystallize in the C2/m monoclinic system with lattice parameters, a=12.4049(4)12.7621(6) Å, b=5.8414(2)5.9488(3) Å, c=7.3489(2)7.6424(4) Å, β=107.425(3)107.432(2)° and Z=2. The crystal structure is isotypic with the defect/disorder model of Ln5Re2O12 (Ln = Y, Gd) and consists of one dimensional edge shared RuO6 octahedral chains separated by a two dimensional LnOx polyhedral framework. Magnetic measurements indicate paramagnetic and antiferromagnetic behavior for Ln=Nd, SmGd and Ln=Tb, respectively. |
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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 |
000265893700027 |
Publication Date |
2009-02-22 |
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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 |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.299 |
Times cited |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.299; 2009 IF: 2.340 |
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Call Number |
UA @ lucian @ c:irua:77052 |
Serial |
3433 |
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| Permanent link to this record |
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Author |
Stefaniak, E.A.; Alsecz, A.; Frost, R.; Máthé, Z.; Sajó, I.E.; Török, S.; Worobiec, A.; Van Grieken, R. |
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Title |
Combined SEM/EDX and micro-Raman spectroscopy analysis of uranium minerals from a former uranium mine |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of hazardous materials |
Abbreviated Journal |
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Volume |
168 |
Issue |
1 |
Pages |
416-423 |
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Keywords |
A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Samples of the secondary uranium minerals collected in the abandoned uranium mine at Pecs (Hungary) were investigated by two micro-techniques: scanning electron microscopy (SEM/EDX) and micro-Raman spectroscopy (MRS). They were applied to locate U-rich particles and identify the chemical form and oxidation state of the uranium compounds. The most abundant mineral was a K and/or Na uranyl sulphate (zippeite group). U(VI) was also present in the form showing intensive Raman scattering at 860 cm−1 which can be attributed to uranium trioxide. This research has shown the successful application of micro-Raman spectroscopy for the identification of uranyl mineral species on the level of individual particles. |
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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 |
000267567600060 |
Publication Date |
2009-02-22 |
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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 |
0304-3894 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:77032 |
Serial |
7681 |
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| Permanent link to this record |
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Author |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
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Title |
Adsorption of small molecules on graphene |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
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| |
Volume |
40 |
Issue |
4/5 |
Pages |
860-862 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the adsorption process of small molecules on graphene through first-principles calculations and show the presence of two main charge transfer mechanisms. Which mechanism is the dominant one depends on the magnetic properties of the adsorbing molecules. We explain these mechanisms through the density of states of the system and the molecular orbitals of the adsorbates, and demonstrate the possible difficulties in calculating the charge transfer from first principles between a graphene sheet and a molecule. Our results are in good agreement with experiment. |
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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 |
Luton |
Editor |
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Language |
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Wos |
000265870200058 |
Publication Date |
2008-12-26 |
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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 |
0026-2692; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.163 |
Times cited |
116 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
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Call Number |
UA @ lucian @ c:irua:77030 |
Serial |
65 |
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| Permanent link to this record |
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Author |
Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M. |
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Title |
Neutral shallow donors near a metallic interface |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
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| |
Volume |
40 |
Issue |
4/5 |
Pages |
753-755 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The effect of a metallic gate on the bound states of a shallow donor located near the gate is studied. We calculate the energy spectrum as a function of the distance between the metallic gate and the donor and find an anti-crossing behavior in the energy levels for certain distances. We show how a transverse electric field can tune the average position of the electron with respect to the metallic gate and the impurity. |
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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 |
Luton |
Editor |
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Language |
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Wos |
000265870200024 |
Publication Date |
2009-02-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0026-2692; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.163 |
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
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Call Number |
UA @ lucian @ c:irua:77029 |
Serial |
2296 |
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| Permanent link to this record |
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Author |
Masir, M.R.; Matulis, A.; Peeters, F.M. |
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Title |
Quasibound states of Schrödinger and Dirac electrons in a magnetic quantum dot |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
79 |
Issue |
15 |
Pages |
155451,1-155451,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The properties of a two-dimensional electron are investigated in the presence of a circular step magnetic-field profile. Both electrons with parabolic dispersion as well as Dirac electrons with linear dispersion are studied. We found that in such a magnetic quantum dot no electrons can be confined. Nevertheless close to the Landau levels quasibound states can exist with a rather long lifetime. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000265944200140 |
Publication Date |
2009-04-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
55 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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Call Number |
UA @ lucian @ c:irua:77026 |
Serial |
2800 |
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| Permanent link to this record |
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Author |
Barbier, M.; Vasilopoulos, P.; Peeters, F.M.; Pereira, J.M. |
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Title |
Bilayer graphene with single and multiple electrostatic barriers: band structure and transmission |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
79 |
Issue |
15 |
Pages |
155402,1-155402,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We evaluate the electronic transmission and conductance in bilayer graphene through a finite number of potential barriers. Further, we evaluate the dispersion relation in a bilayer graphene superlattice with a periodic potential applied to both layers. As a model we use the tight-binding Hamiltonian in the continuum approximation. For zero bias the dispersion relation shows a finite gap for carriers with zero momentum in the direction parallel to the barriers. This is in contrast to single-layer graphene where no such gap was found. A gap also appears for a finite bias. Numerical results for the energy spectrum, conductance, and the density of states are presented and contrasted with those pertaining to single-layer graphene. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000265944200091 |
Publication Date |
2009-04-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
74 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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| |
Call Number |
UA @ lucian @ c:irua:77025 |
Serial |
235 |
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| Permanent link to this record |
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Author |
Tadić, M.; Peeters, F.M. |
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Title |
Excitonic properties of strained triple quantum-ring molecules |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
79 |
Issue |
15 |
Pages |
153305,1-153305,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The tunneling coupling in three vertically stacked (In,Ga)As/GaAs quantum rings is investigated. With increasing inter-ring separation (d), we find that the nonuniform strain results into a crossing of the lowest-energy electron states. Strain is also responsible for an increase in the ground electron energy above the level in the single quantum ring. The ground hole energy level exhibits decrease when d decreases, which is typical for antibonding states in an unstrained structure. These effects lead to a local maximum in the dependence of the ground-state exciton energy on d. Our theoretical results compare well with recent photoluminescence measurements but deviate considerably from the calculations for flat bands in quantum-ring molecules. We conclude that the nonuniform character of the strain distribution gives rise to a peculiar exciton hybridization in self-assembled quantum-ring molecules. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000265944200018 |
Publication Date |
2009-04-21 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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| |
Call Number |
UA @ lucian @ c:irua:77024 |
Serial |
1123 |
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| Permanent link to this record |
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Author |
Moshnyaga, V.; Gehrke, K.; Sudheendra, L.; Belenchuk, A.; Raabe, S.; Shapoval, O.; Verbeeck, J.; Van Tendeloo, G.; Samwer, K. |
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| |
Title |
Electrical nonlinearity in colossal magnetoresistance manganite films: relevance of correlated polarons |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
79 |
Issue |
13 |
Pages |
134413,1-134413,8 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
The metal-insulator (MI) transition in epitaxial thin films of La0.75Ca0.25MnO3 (LCMO) is accompanied by the appearance of an intrinsic electrical nonlinearity. The latter, probed by electrical third harmonic voltage, U3, or resistance, R3=dU3/dJ, is drastically enhanced in the vicinity of the MI transition, TMI=267 K. Applied magnetic field, B=5 T, suppresses the nonlinearity, resulting in a huge nonlinear CMR3(TMI)~105%. R3 shows a peculiar low-frequency (1 kHz) dependence, R3~(-0)n, with exponent, n, changing across the MI transition from n~1,52 for TTMI to n=1 (T<TMI). The observed electrical nonlinearity in LCMO reflects the behavior of correlated polarons, the number of which dramatically enhances in the vicinity of TMI. We argued that correlated polarons, considered as electric-elastic quadrupoles, provide a nonlinear (quadratic) coupling to the electric field, yielding a third harmonic electric nonlinearity in LCMO. The reference film of La0.7Sr0.3MnO3 (LSMO), a prototypic double exchange system with second-order phase transition, is characterized as a linear metallic material in the whole range of temperatures (T=10400 K), magnetic fields (B=05 T), and frequencies (=11000 Hz). |
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| |
Address |
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| |
Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
| |
Language |
|
Wos |
000265942800074 |
Publication Date |
2009-04-09 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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| |
Call Number |
UA @ lucian @ c:irua:77022UA @ admin @ c:irua:77022 |
Serial |
893 |
|
| Permanent link to this record |
| |
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| |
|
Author |
Yang, W.; Nelissen, K.; Kong, M.; Zeng, Z.; Peeters, F.M. |
|
| |
Title |
Structure of binary colloidal systems confined in a quasi-one-dimensional channel |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
|
| |
Volume |
79 |
Issue |
4 |
Pages |
041406,1-041406,6 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The structural properties of a binary colloidal quasi-one-dimensional system confined in a narrow channel are investigated through modified Monte Carlo simulations. Two species of particles with different magnetic moment interact through a repulsive dipole-dipole force are confined in a quasi-one-dimensional channel. The impact of three decisive parameters (the density of particles, the magnetic-moment ratio, and the fraction between the two species) on the transition from disordered phase to crystal-like phases and the transitions among the different mixed phases are summarized in a phase diagram. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
| |
Language |
|
Wos |
000265941300077 |
Publication Date |
2009-04-23 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.366 |
Times cited |
11 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.366; 2009 IF: 2.400 |
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| |
Call Number |
UA @ lucian @ c:irua:77021 |
Serial |
3308 |
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| Permanent link to this record |
| |
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| |
|
Author |
Lindner, H.; Autrique, D.; Garcia, C.C.; Niemax, K.; Bogaerts, A. |
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| |
Title |
Optimized transport setup for high repetition rate pulse-separated analysis in laser ablation-inductively coupled plasma mass spectrometry |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
| |
Volume |
81 |
Issue |
11 |
Pages |
4241-4248 |
|
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
An optimized laser ablation setup, proposed for high repetition rate inductively coupled plasma mass spectrometry (ICPMS) analyses such as 2D imaging or depth profiling, is presented. For such applications, the particle washout time needs to be as short as possible to allow high laser pulse frequencies for reduced analysis time. Therefore, it is desirable to have an ablation setup that operates as a laminar flow reactor (LFR). A top-down strategy was applied that resulted in the present design. In the first step, a previously applied ablation setup was analyzed on the basis of computational fluid dynamics (CFD) results presented by D. Autrique et al. (Spectrochim. Acta, B 2008, 63, 257−270). By means of CFD simulations, the design was modified in such a way that it operated in the LFR regime. Experimental results demonstrate that the current design can indeed be regarded as an LFR. Furthermore, the operation under LFR conditions allowed some insight into the initial radial concentration distribution if the experimental ICPMS signal and analytical expressions are taken into account. Recommendations for a modified setup for more resilient spatial distributions are given. With the present setup, a washout time of 140 ms has been achieved for a 3% signal area criterion. Therefore, 7 Hz repetition rates can be applied with the present setup. Using elementary formulas of the analytical model, an upper bound for the washout times for similar setups can be predicted. The authors believe that the presented setup geometry comes close to the achievable limit for reliable short washout times. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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| |
Language |
|
Wos |
000266601800014 |
Publication Date |
2009-04-29 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-2700;1520-6882; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
6.32 |
Times cited |
18 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 6.32; 2009 IF: 5.214 |
|
| |
Call Number |
UA @ lucian @ c:irua:76935 |
Serial |
2492 |
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| Permanent link to this record |
| |
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| |
|
Author |
Bencs, L.; Ravindra, K.; de Hoog, J.; Rasoazanany, E.O.; Deutsch, F.; Bleux, N.; Berghmans, P.; Roekens, E.; Krata, A.; Van Grieken, R. |
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| |
Title |
Mass and ionic composition of atmospheric fine particles over Belgium and their relation with gaseous air pollutants |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Journal of environmental monitoring |
Abbreviated Journal |
|
|
| |
Volume |
10 |
Issue |
10 |
Pages |
1148-1157 |
|
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
Mass, major ionic components (MICs) of PM2.5, and related gaseous pollutants (SO2, NOx, NH3, HNO2, and HNO3) were monitored over six locations of different anthropogenic influence (industrial, urban, suburban, and rural) in Belgium. SO42-, NO3-, NH4+, and Na+ were the primary ions of PM2.5 with averages diurnal concentrations ranging from 0.44.5, 0.37.6, 0.94.9, and 0.41.2 µg m-3, respectively. MICs formed 39% of PM2.5 on an average, but it could reach up to 8098%. The SO2, NO, NO2, HNO2, and HNO3 levels showed high seasonal and site-specific fluctuations. The NH3 levels were similar over all the sites (26 µg m-3), indicating its relation to the evenly distributed animal husbandry activities. The sulfur and nitrogen oxidation ratios for PM2.5 point towards a low-to-moderate formation of secondary sulfate and nitrate aerosols over five cities/towns, but their fairly intensive formation over the rural Wingene. Cluster analysis revealed the association of three groups of compounds in PM2.5: (i) NH4NO3, KNO3; (ii) Na2SO4; and (iii) MgCl2, CaCl2, MgF2, CaF2, corresponding to anthropogenic, sea-salt, and mixed (sea-salt + anthropogenic) aerosols, respectively. The neutralization and cation-to-anion ratios indicate that MICs of PM2.5 appeared mostly as (NH4)2SO4 and NH4NO3 salts. Sea-salt input was maximal during winter reaching up to 12% of PM2.5. The overall average Cl-loss for sea-salt particles of PM2.5 at the six sites varied between 69 and 96% with an average of 87%. Principal component analysis revealed vehicular emission, coal/wood burning and animal farming as the dominating sources for the ionic components of PM2.5. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
|
Editor |
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| |
Language |
|
Wos |
000259890100005 |
Publication Date |
2008-10-21 |
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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 |
1464-0325; 1464-0333 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
UA @ admin @ c:irua:76876 |
Serial |
8206 |
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| Permanent link to this record |
| |
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| |
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Author |
Milošević, M.M.; Tadić, M.; Peeters, F.M. |
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| |
Title |
Effects of lateral asymmetry on electronic structure of strained semiconductor nanorings in a magnetic field |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
19 |
Issue |
45 |
Pages |
|
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The influence of lateral asymmetry on the electronic structure and optical transitions in elliptical strained InAs nanorings is analyzed in the presence of a perpendicular magnetic field. Two-dimensional rings are assumed to have elliptical inner and outer boundaries oriented in mutually orthogonal directions. The influence of the eccentricity of the ring on the energy levels is analyzed. For large eccentricity of the ring, we do not find any AharonovBohm effect, in contrast to circular rings. Rather, the single-particle states of the electrons and the holes are localized as in two laterally coupled quantum dots formed in the lobes of the nanoring. Our work indicates that the control of shape is important for the existence of the AharonovBohm effect in semiconductor nanorings. |
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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 |
Bristol |
Editor |
|
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| |
Language |
|
Wos |
000259922000016 |
Publication Date |
2008-10-09 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
11 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.44; 2008 IF: 3.446 |
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| |
Call Number |
UA @ lucian @ c:irua:76874 |
Serial |
865 |
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| Permanent link to this record |
| |
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| |
|
Author |
Smeulders, G.; Meynen, V.; van Baelen, G.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Maes, B.U.W.; Cool, P. |
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| |
Title |
Rapid microwave-assisted synthesis of benzene bridged periodic mesoporous organosilicas |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
|
| |
Volume |
19 |
Issue |
19 |
Pages |
3042-3048 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY) |
|
| |
Abstract |
Following extended use in organic chemistry, microwave-assisted synthesis is gaining more importance in the field of inorganic chemistry, especially for the synthesis of nanoporous materials. It offers some major advantages such as a significant shortening of the synthesis time and an improved promotion of nucleation. In the research here reported, microwave technology is applied for the synthesis of benzene bridged PMOs (periodic mesoporous organosilicas). PMOs are one of the latest innovations in the field of hybrid ordered mesoporous materials and have attracted much attention because of their feasibility in electronics, catalysis, separation and sorption applications. The different synthesis steps (stirring, aging and extraction) of the classical PMO synthesis are replaced by microwave-assisted synthesis steps. The characteristics of the as-synthesized materials are evaluated by X-ray diffraction, N2-sorption, thermogravimetric analysis, scanning- and transmission electron microscopy. The microwave-assisted synthesis drastically reduces the synthesis time by more than 40 hours without any loss in structural properties, such as mesoscale and molecular ordering. The porosity of the PMO materials has even been improved by more than 25%. Moreover, the number of handling/transfer steps and amounts of chemicals and waste are drastically reduced. The study also shows that there is a clear time (1 to 3 hours) and temperature frame (373 K to 403 K) wherein synthesis of benzene bridged PMO is optimal. In conclusion, the microwave-assisted synthesis pathway allows an improved material to be obtained in a more economical way i.e. a much shorter time with fewer chemicals and less waste. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Cambridge |
Editor |
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| |
Language |
|
Wos |
000265919300024 |
Publication Date |
2009-03-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
20 |
Open Access |
|
|
| |
Notes |
Fwo; Iwt |
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ lucian @ c:irua:76844 |
Serial |
2810 |
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| Permanent link to this record |
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| |
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Author |
Bogaerts, A.; Bultinck, E.; Eckert, M.; Georgieva, V.; Mao, M.; Neyts, E.; Schwaederlé, L. |
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| |
Title |
Computer modeling of plasmas and plasma-surface interactions |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Plasma processes and polymers |
Abbreviated Journal |
Plasma Process Polym |
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| |
Volume |
6 |
Issue |
5 |
Pages |
295-307 |
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| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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| |
Abstract |
In this paper, an overview is given of different modeling approaches used for describing gas discharge plasmas, as well as plasma-surface interactions. A fluid model is illustrated for describing the detailed plasma chemistry in capacitively coupled rf discharges. The strengths and limitations of Monte Carlo simulations and of a particle-in-cell-Monte Carlo collisions model are explained for a magnetron discharge, whereas the capabilities of a hybrid Monte Carlo-fluid approach are illustrated for a direct current glow discharge used for spectrochemical analysis of materials. Finally, some examples of molecular dynamics simulations, for the purpose of plasma-deposition, are given. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Weinheim |
Editor |
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| |
Language |
|
Wos |
000266471800003 |
Publication Date |
2009-04-20 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1612-8850;1612-8869; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.846 |
Times cited |
18 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.846; 2009 IF: 4.037 |
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| |
Call Number |
UA @ lucian @ c:irua:76833 |
Serial |
461 |
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| Permanent link to this record |
| |
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| |
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Author |
Lepoittevin, C.; Malo, S.; Nguyen, N.; Hebert, S.; Van Tendeloo, G.; Hervieu, M. |
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| |
Title |
A layered iron-rich 2234-type with a mixed valence of iron: the ferrimagnetic Tl-doped Fe2(Sr2-\varepsilonTl\varepsilon)Sr3Fe4O14.65 |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
20 |
Issue |
20 |
Pages |
6468-6476 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
A new Tl-doped strontium ferrite Fe2(Sr2-Tl)Sr3Fe4O14.65, with an original structure, has been synthesized and structurally characterized by powder X-ray diffraction and transmission electron microscopy. The TGA and Mssbauer studies evidence a mixed valence of iron. The structure exhibits a commensurate modulation, with a F-type subcell a ≈ b ≈ 5.4 Å (≈ ap√2), c ≈ 42 Å with a modulation vector q = αa* with α = 0.4. The supercell parameters have been refined as a= 27.1101(8) Å, b= 5.5187(2) Å and c= 42.0513(9) Å, in the space group Fmmm. The electron diffraction and electron microscopy data of this novel ferrite show that it can be described as a FeTl-2234-type structure corresponding to the intergrowth of a quadruple perovskite slice [(SrFeO2.8)4], with a complex rock salt related slice [Fe2(Sr2-Tl)O3.4]∞, built up of one double iron layer [Fe2O2.4] sandwiched between two [SrO] layers. The HRTEM images show that the oxygen atoms and vacancies are randomly distributed in the perovskite layers while the HAADF STEM images evidence the absence of Tl segregation in the matrix. Fe2(Sr2-Tl)Sr3Fe4O14.65 exhibits a very large value of χ (11emu/mol) at 5 K, which remains large at 400 K; the M(H) loop presents a shape characteristic of ferrimagnetism, with a large coercive field of 0.3 T. The value of magnetization saturates at 400 K at 0.68 μB/Fe. At 10 K, the value of magnetization reaches a maximum of 2 μB/Fe. The resistivity presents a semiconducting-like behavior, with ρ 800 Ω·cm at 300 K. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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| |
Language |
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Wos |
000260254400030 |
Publication Date |
2008-09-25 |
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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 |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
9.466 |
Times cited |
8 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 9.466; 2008 IF: 5.046 |
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| |
Call Number |
UA @ lucian @ c:irua:76671 |
Serial |
1804 |
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| Permanent link to this record |
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| |
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Author |
Major, L.; Tirry, W.; Van Tendeloo, G. |
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| |
Title |
Microstructure and defect characterization at interfaces in TiN/CrN multilayer coatings |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Surface and coatings technology |
Abbreviated Journal |
Surf Coat Tech |
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| |
Volume |
202 |
Issue |
24 |
Pages |
6075-6080 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Microstructures of TiN/CrN multilayer coatings deposited on austenite steel (Cr Ni 18 8) by pulsed laser deposition (PLD) are characterized using transmission electron microscopy while their mechanical properties were assessed in a ball-on-disk test. All coatings have the same total thickness of about 1 ìm. The individual layers show a highly defective columnar structure, which is characterized by conventional electron microscopy (TEM) as well as by high resolution TEM. These techniques, combined with measurements of the local chemical composition through EDS prove that PLD allows to produce fully separated CrN and TiN layers. The friction, and consequently the wear, are lowered by increasing the total number of layers in the coating. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Lausanne |
Editor |
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| |
Language |
|
Wos |
000260267100042 |
Publication Date |
2008-07-20 |
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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 |
0257-8972; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.589 |
Times cited |
23 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.589; 2008 IF: 1.860 |
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| |
Call Number |
UA @ lucian @ c:irua:76614 |
Serial |
2049 |
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| Permanent link to this record |
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| |
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Author |
Turner, S.; Lebedev, O.I.; Schroeder, F.; Fischer, R.A.; Van Tendeloo, G. |
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| |
Title |
Direct imaging of loaded metal-organic framework materials (metal@MOF-5) |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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| |
Volume |
20 |
Issue |
17 |
Pages |
5622-5627 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We illustrate the potential of advanced transmission electron microscopy for the characterization of a new class of soft porous materials: metal@Zn4O(bdc)3 (metal@MOF-5; bdc = 1,4-benzenedicarboxylate). By combining several electron microscopy techniques (transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and electron tomography) and by carefully reducing the electron dose to avoid beam damage, it is possible to simultaneously characterize the MOF-5 framework material and the loaded metal nanoparticles. We also demonstrate that electron tomography can be used to accurately determine the position and distribution of the particles within the MOF-5 framework. To demonstrate the implementation of these microscopy techniques and what kind of results can be expected, measurements on gas-phase-loaded metal−organic framework materials Ru@MOF-5 and Pd@MOF-5 are presented. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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| |
Language |
|
Wos |
000258941400021 |
Publication Date |
2008-08-07 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
9.466 |
Times cited |
112 |
Open Access |
|
|
| |
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2008 IF: 5.046 |
|
| |
Call Number |
UA @ lucian @ c:irua:76595 |
Serial |
714 |
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| Permanent link to this record |
| |
|
| |
|
Author |
Nowak, M.P.; Szafran, B.; Peeters, F.M. |
|
| |
Title |
Manipulation of two-electron states by the electric field in stacked self-assembled dots |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
20 |
Issue |
39 |
Pages |
395225,1-395225,14 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
A pair of electrons in vertically stacked self-assembled quantum dots is studied and the singlettriplet energy splitting is calculated in an external electric field using the configuration-interaction method. We show that for double quantum dots the dependence of the singlet energy levels on the electric field involves multiple avoided crossings of three energy levels. The exchange interaction, i.e., the energy difference of the lowest triplet and lowest singlet states, can be tuned by an electric field in a wide range of several tens of meV. For electric fields exceeding a threshold value the exchange interaction becomes a linear function of the field when the two electrons in the singlet state start to occupy the same dot. We also consider non-symmetric confinement, non-perfectly aligned dots, in horizontal as well as vertical field orientation. In a stack of three vertically coupled dots the depth of the confinement in the central dot can be used to enhance the exchange interaction. For a deeper central dot the dependence of the exchange interaction on the electric field is anomalousit initially decreases when the field is applied in both directions parallel and antiparallel to the axis of the stack. Such a behavior is never observed for a pair of quantum dots. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
London |
Editor |
|
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| |
Language |
|
Wos |
000259034200032 |
Publication Date |
2008-09-05 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.649; 2008 IF: 1.900 |
|
| |
Call Number |
UA @ lucian @ c:irua:76592 |
Serial |
1940 |
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| Permanent link to this record |
| |
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| |
|
Author |
Zhao, H.-W.; Zha, G.-Q.; Zhou, S.-P.; Peeters, F.M. |
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| |
Title |
Long-range Coulomb repulsion effect on a charged vortex in high-temperature superconductors with competing d-wave and antiferromagnetic orders |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
78 |
Issue |
6 |
Pages |
064505,1-064505,5 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Vortex charges in high-temperature superconductor (HTS) are studied by solving the Bogoliubovde Gennes equations based on a model Hamiltonian with antiferromagnetic (AF) and d-wave orders in the presence of the long-range Coulomb repulsion. For a sufficient strength of the AF order, the negative vortex charge is found. A sign change between negative and positive may occur by tuning the long-range Coulomb repulsion strength or the doping parameter. Recent NMR experiments are hopefully understood. We show that the charged vortex can induce a spin-orbit coupling that is important for superconductors with a short coherence length and a large value of the energy gap over the Fermi-level ratio. Fractional flux quanta are possible for HTS. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
| |
Language |
|
Wos |
000259264900084 |
Publication Date |
2008-08-06 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
|
| |
Call Number |
UA @ lucian @ c:irua:76553 |
Serial |
1837 |
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| Permanent link to this record |
| |
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| |
|
Author |
Schweigert, I.V.; Alexandrov, A.L.; Ariskin, D.A.; Peeters, F.M.; Stefanović, I.; Kovačević, E.; Berndt, J.; Winter, J. |
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| |
Title |
Effect of transport of growing nanoparticles on capacitively coupled rf discharge dynamics |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
|
| |
Volume |
78 |
Issue |
2 |
Pages |
026410,1-026410,6 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We present experimental and numerical studies of the properties of a capacitively coupled 13.56 MHz discharge in a mixture of Ar and C2H2 with growing nanosize particles. It is found that at the initial stage of the growth, nanoparticles are accumulated near the sheath-plasma boundaries, where the ionization by electrons is maximal. The nanoparticles suppress the ionization due to the absorbing fast electrons and stimulate a quick change of the plasma parameters followed by a transition between different modes of discharge operation. At that moment the peaked distribution of the dust particles transforms into a flat one. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
| |
Language |
|
Wos |
000259263700071 |
Publication Date |
2008-08-20 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.366 |
Times cited |
36 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.366; 2008 IF: 2.508 |
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| |
Call Number |
UA @ lucian @ c:irua:76552 |
Serial |
851 |
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| Permanent link to this record |
| |
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| |
|
Author |
Michel, K.H.; Verberck, B. |
|
| |
Title |
Theory of the evolution of phonon spectra and elastic constants from graphene to graphite |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
78 |
Issue |
8 |
Pages |
085424,1-085424,17 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We present a unified theory of the phonon dispersions and elastic properties of graphene, graphite, and graphene multilayer systems. Starting from a fifth-nearest-neighbor force-constant model derived from full in-plane phonon dispersions of graphite [Mohr et al., Phys. Rev. B 76, 035439 (2007)], we use Born's long-wave method to calculate the tension and bending coefficients of graphene. Extending the model by interplanar interactions, we study the phonon dispersions and the elastic constants of graphite, and the phonon spectra of graphene multilayers. We find that the inner displacement terms due to sublattice shifts between inequivalent C atoms are quantitatively important in determining the elastomechanical properties of graphene and of graphite. The overall agreement between theory and experiment is very satisfactory. We investigate the evolution from graphene to graphite by studying the increase in the rigid plane optical mode as a function of the number of layers N. At N=10 the graphite value B2g1127 cm−1 is attained within a few percent. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
|
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| |
Language |
|
Wos |
000259406900106 |
Publication Date |
2008-08-21 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
72 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
|
| |
Call Number |
UA @ lucian @ c:irua:76527 |
Serial |
3622 |
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| Permanent link to this record |
| |
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| |
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
|
| |
Title |
Superconducting nanofilms: Andreev-type states induced by quantum confinement |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
78 |
Issue |
5 |
Pages |
054505,1-054505,8 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Quantum confinement of the transverse electron motion is the major effect governing the superconducting properties of high-quality metallic nanofilms, leading to a nonuniform transverse distribution of the superconducting condensate. In this case the order parameter can exhibit significant local enhancements due to these quantum-size effects and, consequently, quasiparticles have lower energies when they avoid the local enhancements of the pair condensate. Such excitations can be considered as new Andreev-type quasiparticles but now induced by quantum confinement. By numerically solving the Bogoliubovde Gennes equations and using Anderson's approximate solution to these equations, we: (a) formulate a criterion for such new Andreev-type states (NATS) and (b) study their effect on the superconducting characteristics in metallic nanofilms. We also argue that nanofilms made of low-carrier-density materials, e.g., of superconducting semiconductors, can be a more optimal choice for the observations of NATS and other quantum-size superconducting effects. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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| |
Language |
|
Wos |
000259368200109 |
Publication Date |
2008-08-11 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
|
| |
Call Number |
UA @ lucian @ c:irua:76526 |
Serial |
3356 |
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| Permanent link to this record |
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| |
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Author |
Doria, M.M.; Brandt, E.H.; Peeters, F.M. |
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| |
Title |
Magnetization of a superconducting film in a perpendicular magnetic field |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
78 |
Issue |
5 |
Pages |
0544047,1-054407,7 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
With large thin superconducting films in a perpendicular magnetic field, the usual definition and calculation of the magnetization M via currents or as the difference of two fields fail, since the spatially averaged magnetic field in the film coincides with the uniform applied field and the demagnetization factor is unity. The definition of M as field-derivative of the free energy, however, still works in this limit. We generalize the virial theorem, previously derived for infinite bulk superconductors, to infinitely extended films of arbitrary thickness. An expression for M is obtained that indeed reproduces the M computed from the field derivative of the free energy. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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| |
Language |
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Wos |
000259368200063 |
Publication Date |
2008-08-08 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
|
| |
Call Number |
UA @ lucian @ c:irua:76525 |
Serial |
1895 |
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| Permanent link to this record |
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| |
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Author |
Montoya, E.; Bals, S.; Van Tendeloo, G. |
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| |
Title |
Redeposition and differential sputtering of La in transmission electron microscopy samples of LaAIO3/SrTiO3 multilayers prepared by focused ion beam |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Journal of microscopy |
Abbreviated Journal |
J Microsc-Oxford |
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| |
Volume |
231 |
Issue |
3 |
Pages |
359-363 |
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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 |
|
Place of Publication |
Oxford |
Editor |
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| |
Language |
|
Wos |
000259611000001 |
Publication Date |
2008-08-28 |
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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 |
0022-2720;1365-2818; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
1.692 |
Times cited |
|
Open Access |
|
|
| |
Notes |
The authors are grateful to M. Huijben and G. Rijnders of the MESA+ group at the University of Twente (NI) for the growth of the multilayers. This work has been performed under the Interuniversity Attraction Poles programme – Belgian State Belgian Science Policy. The authors acknowledge financial support from the European Union under the framework 6 program under a contract for an Integrated Infrastructure initiative. Part of this work was performed with financial support from the European Union under the framework 6 programme, under a contract for an Integrated Infrastructure Initiative (Reference No. 02601.9 ESTEEM). |
Approved |
Most recent IF: 1.692; 2008 IF: 1.409 |
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| |
Call Number |
UA @ lucian @ c:irua:76522 |
Serial |
2849 |
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| Permanent link to this record |
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| |
|
Author |
Alexandrov, A.L.; Schweigert, I.V.; Peeters, F.M. |
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| |
Title |
A non-Maxwellian kinetic approach for charging of dust particles in discharge plasmas |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
|
| |
Volume |
10 |
Issue |
|
Pages |
093025,1-093025,12 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Nanoparticle charging in a capacitively coupled radio frequency discharge in argon is studied using a particle in cell Monte Carlo collisions method. The plasma parameters and dust potential were calculated self-consistently for different unmovable dust profiles. A new method for definition of the dust floating potential is proposed, based on the information about electron and ion energy distribution functions, obtained during the kinetic simulations. This approach provides an accurate balance of the electron and ion currents on the dust particle surface and allows us to precisely calculate the dust floating potential. A comparison of the obtained floating potentials with the results of the traditional orbital motion limit (OML) theory shows that in the presence of the ion resonant charge exchange collisions, even when the OML approximation is valid, its results are correct only in the region of a weak electric field, where the ion drift velocity is much smaller than the thermal one. With increasing ion drift velocity, the absolute value of the calculated dust potential becomes significantly smaller than the theory predicts. This is explained by a non-Maxwellian shape of the ion energy distribution function for the case of fast ion drift. |
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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 |
Bristol |
Editor |
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| |
Language |
|
Wos |
000259615700004 |
Publication Date |
2008-09-24 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.786 |
Times cited |
19 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.786; 2008 IF: 3.440 |
|
| |
Call Number |
UA @ lucian @ c:irua:76519 |
Serial |
2348 |
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| Permanent link to this record |
| |
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| |
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Author |
Das, P.; Koblischka, M.R.; Turner, S.; Van Tendeloo, G.; Wolf, T.; Jirsa, M.; Hartmann, U. |
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| |
Title |
Direct observation of nanometer-scale pinning sites in (Nd0.33Eu0.20Gd0.47)Ba2Cu3O7-\delta single crystals |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
|
| |
Volume |
83 |
Issue |
3 |
Pages |
37005,1-37005,4 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We report on the observation of self-organized stripe-like structures on the as-grown surface and in the bulk of (Nd,Eu,Gd)Ba2Cu3Oy single crystals. The periodicity of the stripes on the surface lies between 500800 nm. These are possibly the growth steps of the crystal. Transmission electron microscopy investigations revealed stripes of periodicity in the range of 2040 nm in the bulk. From electron back scattered diffraction investigations, no crystallographic misorientation due to the nanostripes has been found. Scanning tunneling spectroscopic experiments revealed nonsuperconducting regions, running along twin directions, which presumably constitute strong pinning sites. |
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| |
Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Paris |
Editor |
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| |
Language |
|
Wos |
000259022600032 |
Publication Date |
2008-07-18 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.957 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 1.957; 2008 IF: 2.203 |
|
| |
Call Number |
UA @ lucian @ c:irua:76496 |
Serial |
719 |
|
| Permanent link to this record |
