Records |
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lamoen, D.; March, N.H. |
Title |
Orientational disorder in some molecular solids in relation to the boson peak in glasses |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physics letters : A |
Abbreviated Journal |
Phys Lett A |
Volume |
373 |
Issue |
7 |
Pages |
799-800 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Orientational disorder in some molecular solids is discussed in relation to the emphasis placed on transverse vibrational modes in glasses as the origin of the observed boson peak in two very recent contributions in Nature Materials. In particular, facts are here presented for (i) CH4, (ii) C60 and (iii) ethanol in their solid phases for (a) specific heat and (b) neutron scattering. The results for ethanol in particular do not fit in with the interpretation of the boson peak in terms of transverse acoustic phonons in disordered systems. Glasses will therefore have to be separated into at least two classes where the physical interpretation of the boson peak is concerned. |
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 |
000263515500020 |
Publication Date |
2009-01-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0375-9601; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.772 |
Times cited |
3 |
Open Access |
|
Notes |
Bof |
Approved |
Most recent IF: 1.772; 2009 IF: 2.009 |
Call Number |
UA @ lucian @ c:irua:72917 |
Serial |
2516 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
Title |
Adsorption of small molecules on graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
Volume |
40 |
Issue |
4/5 |
Pages |
860-862 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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. |
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 |
|
Language |
|
Wos |
000265870200058 |
Publication Date |
2008-12-26 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-2692; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.163 |
Times cited |
116 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
Call Number |
UA @ lucian @ c:irua:77030 |
Serial |
65 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
Title |
Hydrogenation of bilayer graphene and the formation of bilayer graphane from first principles |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
24 |
Pages |
245422,1-245422,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We performed ab initio density-functional theory calculations to investigate the process of hydrogenation of a bilayer of graphene. 50% hydrogen coverage is possible in case that the hydrogen atoms are allowed to adsorb on both sides of the bilayer. In this case interlayer chemical bonding occurs which stabilizes the structure. At maximum coverage, a bilayer of graphane is formed which has properties that are similar to those of a single layer of graphane. |
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 |
|
Language |
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Wos |
000273229200126 |
Publication Date |
2009-12-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
113 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:80578 |
Serial |
1535 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
Title |
Water on graphene: hydrophobicity and dipole moment using density functional theory |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
23 |
Pages |
235440,1-235440,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We apply density-functional theory to study the adsorption of water clusters on the surface of a graphene sheet and find i) graphene is highly hydrophobic and ii) adsorbed water has very little effect on the electronic structure of graphene. A single water cluster on graphene has a very small average dipole moment which is in contrast with an ice layer that exhibits a strong dipole moment. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000267699500147 |
Publication Date |
2009-06-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
292 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77693 |
Serial |
3904 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leon, M.; Merino, J.M.; Van Tendeloo, G. |
Title |
Structural analysis of CuInSe2, CuInTe2 and CuInSeTe by electron microscopy and X-ray techniques |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Acta Microscopica |
Abbreviated Journal |
Acta Microsc |
Volume |
18 |
Issue |
2 |
Pages |
128-138 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A structural research of semiconductor compounds for photovoltaic applications CuInSe(2), CuInTe(2) and CuInSeTe, has been done by x-ray diffraction using the Rietveld analysis of experimental diagrams. Besides, in the CuInSeTe compound the electron diffraction and high resolution microscopy techniques have been used. All the studied compounds were polycrystals with chalcopyrite tetragonal structure, I. 42d. A model for the atomic occupancy in each compound has been proposed, and the results have been compared analyzing the Se-Te substitution effect. |
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 |
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Publication Date |
0000-00-00 |
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 |
|
ISSN |
0798-4545 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.07 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.07; 2009 IF: NA |
Call Number |
UA @ lucian @ c:irua:95679 |
Serial |
3189 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lepoittevin, C.; Hadermann, J.; Malo, S.; Pérez, O.; Van Tendeloo, G.; Hervieu, M. |
Title |
Two variants of the 1/2[110]p(203)p crystallographic shear structures: the phasoid Sr0.61Pb0.18(Fe0.75Mn0.25)O2.29 |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
48 |
Issue |
17 |
Pages |
8257-8262 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
For the composition (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29, a new modulated crystallographic shear structure, related to perovskite, has been synthesized and structurally characterized by transmission electron microscopy. The structure can be described using a monoclinic supercell with cell parameters am = 27.595(2) Å, bm = 3.8786(2) Å, cm = 13.3453(9) Å, and βm = 100.126(5)°, refined from powder X-ray diffraction data. The incommensurate crystallographic shear phases require an alternative approach using the superspace formalism. This allows a unified description of the incommensurate phases from a monoclinically distorted perovskite unit cell and a modulation wave vector. The structure deduced from the high-resolution transmission electron microscopy and high-angle annular dark-field−scanning transmission electron microscopy images is that of a 1/2[110]p(203)p crystallographic shear structure. The structure follows the concept of a phasoid, with two coexisting variants with the same unit cell. The difference is situated at the translational interface, with the local formation of double (phase 2) or single (phase 1) tunnels, where the Pb cations are likely located. |
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 |
000269313500032 |
Publication Date |
2009-07-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
11 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.857; 2009 IF: 4.657 |
Call Number |
UA @ lucian @ c:irua:78482 |
Serial |
3786 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lepoittevin, C.; Malo, S.; Van Tendeloo, G.; Hervieu, M. |
Title |
Synthesis and structural mechanisms of the 2201-type ferrites and polytypes: Fe2(Sr2-xAx)FeO6.5-\delta/2 (A = Ba, La, Tl, Pb and Bi) |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Solid state sciences |
Abbreviated Journal |
Solid State Sci |
Volume |
11 |
Issue |
3 |
Pages |
595-607 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The Fe2(Sr2 − xAx)FeO6.5 − ä/2 systems have been investigated, by doping the iron rich 2201-type parent structure with Ba2+, La3+ and 5d10 post-transition cations. The syntheses have been carried out up to the limit of the 2201-type solid solutions, in order to test the role of the double iron layer Fe2O2.5 − ä/2. The localisation of the charge carriers in these compounds is consistent with their strong antiferro-magnetism. The investigation was then carried out in the transition part of the diagram up to the formation of stable phases. The study of structural mechanisms was carried using high resolution electron microscopy (transmission and scanning transmission), electron diffraction and energy dispersive spectroscopy. Different non-stoichiometry mechanisms are observed, depending on the electronic structure and chemical properties of the doping elements. The specific behavior of the modulated double iron layer is discussed. |
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 |
000264644800001 |
Publication Date |
2008-12-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1293-2558; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.811 |
Times cited |
3 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 1.811; 2009 IF: 1.675 |
Call Number |
UA @ lucian @ c:irua:76416 |
Serial |
3437 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W. |
Title |
Dielectric mismatch effect on coupled impurity states in a freestanding nanowire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
Volume |
40 |
Issue |
3 |
Pages |
446-448 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We studied the coupled impurity states in a freestanding semiconductor nanowire (NW), within the effective mass approximation and including the effect of the dielectric mismatch, by using finite element method. Bonding and anti-bonding states are found and their energies converge with increasing distance di between the two impurities. The dependence of the binding energy on the wire radius R and the distance di between the two impurities is investigated, and we compare it with the result of a freestanding NW that contains a single impurity. |
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 |
000264694700017 |
Publication Date |
2008-07-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-2692; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.163 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
Call Number |
UA @ lucian @ c:irua:76410 |
Serial |
690 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W. |
Title |
Dielectric mismatch effect on coupled shallow impurity states in a semiconductor nanowire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
8 |
Pages |
085306,1-085306,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Coupled shallow impurity states in a freestanding semiconductor nanowire and in a semiconductor nanowire surrounded by a metallic gate are studied within the effective-mass approximation. Bonding and antibonding states are found due to the coupling of the two impurities, and their energy converges with increasing distance di between the two impurities. The dependences of the binding energy on the wire radius R, the distance di between the two impurities, and the impurity radial position in the nanowire are examined. |
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 |
000263816000051 |
Publication Date |
2009-02-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:76223 |
Serial |
691 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Li, J.; Chang, K.; Peeters, F.M. |
Title |
Dyakonov-Perel spin relaxation in InSb/AlxIn1-xSb quantum wells |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
15 |
Pages |
153307,1-153307,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate theoretically the Dyakonov-Perel spin relaxation time by solving the eight-band Kane model and Poisson equation self-consistently. Our results show distinct behavior with the single-band model due to the anomalous spin-orbit interactions in narrow band-gap semiconductors, and agree well with the experiment values reported in recent experiment [K. L. Litvinenko et al., New J. Phys. 8, 49 (2006)]. We find a strong resonant enhancement of the spin relaxation time appears for spin align along [11̅ 0] at a certain electron density at 4 K. This resonant peak is smeared out with increasing the temperature. |
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 |
000271352000015 |
Publication Date |
2009-11-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79996 |
Serial |
760 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lin, K.; Pescarmona, P.P.; Houthoofd, K.; Liang, D.; Van Tendeloo, G.; Jacobs, P.A. |
Title |
Direct room-temperature synthesis of methyl-functionalized Ti-MCM-41 nanoparticles and their catalytic performance in epoxidation |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of catalysis |
Abbreviated Journal |
J Catal |
Volume |
263 |
Issue |
1 |
Pages |
75-82 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Methyl-functionalized Ti-MCM-41 nanoparticles with a size of 80 to 160 nm (Me-Ti-MCM-41 NP) were directly prepared via a dilute solution route by the co-condensation of tetraethoxysilane and methylalkoxysilanes in sodium hydroxide medium at room temperature. The characterization results showed the existence of ordered hexagonal mesoporous structure and tetrahedral Ti species in the nanoparticles. In the epoxidation of cyclohexene with tert-butyl hydroperoxide and aqueous H2O2, Me-Ti-MCM-41 NP samples displayed higher turnover frequencies (TOFs) for cyclohexene and initial reaction rates compared to Ti-MCM-41 and methyl-functionalized Ti-MCM-41 with normal particle size and to non-functionalized Ti-MCM-41 nanoparticles. Simultaneously, a higher selectivity for cyclohexene epoxide was observed in the case of aqueous H2O2, suggesting that the hydrolysis of cyclohexene epoxide with water is reduced on Me-Ti-MCM-41 NP samples. The improved catalytic behavior of Me-Ti-MCM-41 NP is discussed both in terms of the nanosize and methylation of the surface of the catalyst particles. The regeneration of Me-Ti-MCM-41 NP with tert-butyl hydroperoxide solution was evaluated via washing and calcination approaches. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
San Diego, Calif. |
Editor |
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Language |
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Wos |
000265000800008 |
Publication Date |
2009-02-14 |
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 |
|
ISSN |
0021-9517; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.844 |
Times cited |
89 |
Open Access |
|
Notes |
Iwt; Iap; Goa |
Approved |
Most recent IF: 6.844; 2009 IF: 5.288 |
Call Number |
UA @ lucian @ c:irua:76395 |
Serial |
720 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lin, N.S.; Misko, V.R.; Peeters, F.M. |
Title |
Unconventional vortex dynamics in mesoscopic superconducting corbino disks |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
102 |
Issue |
19 |
Pages |
197003,1-197003,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The discrete shell structure of vortex matter strongly influences the flux dynamics in mesoscopic superconducting Corbino disks. While the dynamical behavior is well understood in large and in very small disks, in the intermediate-size regime it occurs to be much more complex and unusual, due to (in)commensurability between the vortex shells. We demonstrate unconventional vortex dynamics (inversion of shell velocities with respect to the gradient driving force) and angular melting (propagating from the boundary where the shear stress is minimum, towards the center) in mesoscopic Corbino disks. |
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 |
000266207700063 |
Publication Date |
2009-05-14 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
18 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.462; 2009 IF: 7.328 |
Call Number |
UA @ lucian @ c:irua:77396 |
Serial |
3800 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lind, O.C.; Salbu, B.; Skipperud, L.; Janssens, K.; Jaroszewicz, J.; de Nolf, W. |
Title |
Solid state speciation and potential bioavailability of depleted uranium particles from Kosovo and Kuwait |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of environmental radioactivity |
Abbreviated Journal |
J Environ Radioactiv |
Volume |
100 |
Issue |
4 |
Pages |
301-307 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A combination of synchrotron radiation based X-ray microscopic techniques (ì-XRF, ì-XANES, ì-XRD) applied on single depleted uranium (DU) particles and semi-bulk leaching experiments has been employed to link the potential bioavailability of DU particles to site-specific particle characteristics. The oxidation states and crystallographic forms of U in DU particles have been determined for individual particles isolated from selected samples collected at different sites in Kosovo and Kuwait that were contaminated by DU ammunition during the 1999 Balkan conflict and the 1991 Gulf war. Furthermore, small soil or sand samples heavily contaminated with DU particles were subjected to simulated gastrointestinal fluid (0.16 M HCl) extractions. Characteristics of DU particles in Kosovo soils collected in 2000 and in Kuwait soils collected in 2002 varied significantly depending on the release scenario and to some extent on weathering conditions. Oxidized U (+6) was determined in large, fragile and bright yellow DU particles released during fire at a DU ammunition storage facility and crystalline phases such as schoepite (UO3·2.25H2O), dehydrated schoepite (UO3·0.75H2O) and metaschoepite (UO3·2.0H2O) were identified. As expected, these DU particles were rapidly dissolved in 0.16 M HCl (84 ± 3% extracted after 2 h) indicating a high degree of potential mobility and bioavailability. In contrast, the 2 h extraction of samples contaminated with DU particles originating either from corrosion of unspent DU penetrators or from impacted DU ammunition appeared to be much slower (2030%) as uranium was less oxidized (+4 to +6). Crystalline phases such as UO2, UC and metallic U or UTi alloy were determined in impacted DU particles from Kosovo and Kuwait, while the UO2,34 phase, only determined in particles from Kosovo, could reflect a more corrosive environment. Although the results are based on a limited number of DU particles, they indicate that the structure and extractability of DU particles released from similar sources (metallic U penetrators) will depend on the release scenarios (fire, impact) and to some extent environmental conditions. However, most of the DU particles (7396%) in all investigated samples were dissolved in 0.16 M HCl after one week indicating that a majority of the DU material is bioaccessible. |
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 |
000264649500004 |
Publication Date |
2009-02-18 |
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 |
|
ISSN |
0265-931x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.31 |
Times cited |
49 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.31; 2009 IF: 1.268 |
Call Number |
UA @ admin @ c:irua:76413 |
Serial |
5834 |
Permanent link to this record |
|
|
|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lindner, H.; Autrique, D.; Garcia, C.C.; Niemax, K.; Bogaerts, A. |
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. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000266601800014 |
Publication Date |
2009-04-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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 |
Permanent link to this record |
|
|
|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lisiecki, I.; Turner, S.; Bals, S.; Pileni, M.P.; Van Tendeloo, G. |
Title |
The remarkable and intriguing resistance to oxidation of 2D ordered hcp Co nanocrystals: a new intrinsic property |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
21 |
Issue |
12 |
Pages |
2335-2338 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000267049200001 |
Publication Date |
2009-05-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
28 |
Open Access |
|
Notes |
Iap-Vi; Esteem 026019 |
Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
Call Number |
UA @ lucian @ c:irua:77887 |
Serial |
2867 |
Permanent link to this record |
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|
|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Liu, S.; Wei, M.; Sui, X.; Cheng, X.; Cool, P.; Van Tendeloo, G. |
Title |
A scanning electron microscopy study on hollow silica microspheres: defects and influences of the synthesis composition |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of sol-gel science and technology |
Abbreviated Journal |
J Sol-Gel Sci Techn |
Volume |
49 |
Issue |
3 |
Pages |
373-379 |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT) |
Abstract |
Defects on hollow silica spheres synthesized in a tetraethylorthosilicate-octylamine-HCl-H2O system were recorded by scanning microscope. Based on the results, influences of synthesis composition on the formation of these defects are discussed. It is evidenced that products prepared with different octylamine-to-tetraethylorthosilicate ratios may have surface depressions, cracks and non-hollow microspheres. However, by changing water and acid additions, these defects could be reduced or eliminated. Generally, samples synthesized with a large octylamine addition commonly exhibit surface depressions. A small octylamine or a large water addition benefits the formation of solid silica microspheres among the product. Acid, although is not indispensable for the formation of hollow spheres, helps to eliminate or reduce depressions on the hollow shells. It is explained that the added acid gives rise to a relative localized fast hydrolysis versus condensation, facilitating an easy mobility of hydrolyzed silica species, and consequently the shell surface is smoothened. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Kluwer |
Place of Publication |
Dordrecht |
Editor |
|
Language |
|
Wos |
000263260100015 |
Publication Date |
2008-12-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0928-0707;1573-4846; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.575 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.575; 2009 IF: 1.393 |
Call Number |
UA @ lucian @ c:irua:74962 |
Serial |
2941 |
Permanent link to this record |
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|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Magnus, W.; Brosens, F.; Sorée, B. |
Title |
Modeling drive currents and leakage currents : a dynamic approach |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
Volume |
8 |
Issue |
3/4 |
Pages |
307-323 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
The dynamics of electrons and holes propagating through the nano-scaled channels of modern semiconductor devices can be seen as a widespread manifestation of non-equilibrium statistical physics and its ruling principles. In this respect both the devices that are pushing conventional CMOS technology towards the final frontiers of Moores law and the upcoming set of alternative, novel nanostructures grounded on entirely new concepts and working principles, provide an almost unlimited playground for assessing physical models and numerical techniques emerging from classical and quantum mechanical non-equilibrium theory. In this paper we revisit the Boltzmann as well as the WignerBoltzmann equation which offers a valuable platform to study transport of charge carriers taking part in drive currents. We focus on a numerical procedure that regained attention recently as an alternative tool to solve the time-dependent Boltzmann equation for inhomogeneous systems, such as the channel regions of field-effect transistors, and we discuss its extension to the WignerBoltzmann equation. Furthermore, we pay attention to the calculation of tunneling leakage currents. The latter typically occurs in nano-scaled transistors when part of the carrier distribution sustaining the drive current is found to tunnel into the gate due the presence of an ultra-thin insulating barrier separating the gate from the channel region. In particular, we discuss the paradox related to the very existence of leakage currents established by electrons occupying quasi-bound states, while the (real) wave functions of the latter cannot carry net currents. Finally, we describe a simple model to resolve the paradox as well as to estimate gate currents provided the local carrier generation rates largely exceed the tunneling rates. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
Language |
|
Wos |
000208236100009 |
Publication Date |
2009-09-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1569-8025;1572-8137; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.526 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.526; 2009 IF: NA |
Call Number |
UA @ lucian @ c:irua:89503 |
Serial |
2110 |
Permanent link to this record |
|
|
|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Magnus, W.; Brosens, F.; Sorée, B. |
Title |
Time dependent transport in 1D micro- and nanostructures: solving the Boltzmann and Wigner-Boltzmann equations |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
Volume |
193 |
Issue |
1 |
Pages |
012004,1-012004,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
For many decades the Boltzmann distribution function has been used to calculate the non-equilibrium properties of mobile particles undergoing the combined action of various scattering mechanisms and externally applied force fields. When the latter give rise to the occurrence of inhomogeneous potential profiles across the region through which the particles are moving, the numerical solution of the Boltzmann equation becomes a highly complicated task. In this work we highlight a particular algorithm that can be used to solve the time dependent Boltzmann equation as well as its quantum mechanical extension, the WignerBoltzmann equation. As an illustration, we show the calculated distribution function describing electrons propagating under the action of both a uniform and a pronouncedly non-uniform electric field. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000277100400004 |
Publication Date |
2009-11-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:82861 |
Serial |
3667 |
Permanent link to this record |
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|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Malard, B.; Pilch, J.; Sittner, P.; Gartnerova, V.; Delville, R.; Schryvers, D.; Curfs, C. |
Title |
Microstructure and functional property changes in thin Ni-Ti wires heat teated by electric current: high energy X-ray and TEM investigations |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Functional materials letters |
Abbreviated Journal |
Funct Mater Lett |
Volume |
2 |
Issue |
2 |
Pages |
45-54 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
High energy synchrotron X-ray diffraction, transmission electron microscopy and mechanical testing were employed to investigate the evolution of microstructure, texture and functional superelastic properties of 0.1 mm thin as drawn NiTi wires subjected to a nonconventional heat treatment by controlled electric current (FTMT-EC method). As drawn NiTi wires were prestrained in tension and exposed to a sequence of short DC power pulses in the millisecond range. The annealing time in the FTMT-EC processing can be very short but the temperature and force could be very high compared to the conventional heat treatment of SMAs. It is shown that the heavily strained, partially amorphous microstructure of the as drawn NiTi wire transforms under the effect of the DC pulse and tensile stress into a wide range of annealed nanosized microstructures depending on the pulse time. The functional superelastic properties and microstructures of the FTMT-EC treated NiTi wire are comparable to those observed in straight annealed wires. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000271077000001 |
Publication Date |
2009-07-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1793-6047;1793-7213; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.234 |
Times cited |
21 |
Open Access |
|
Notes |
Multimat |
Approved |
Most recent IF: 1.234; 2009 IF: 2.561 |
Call Number |
UA @ lucian @ c:irua:77656 |
Serial |
2052 |
Permanent link to this record |
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|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Mandal, T.K.; Croft, M.; Hadermann, J.; Van Tendeloo, G.; Stephens, P.W.; Greenblatt, M. |
Title |
La2MnVO6 double perovskite: a structural, magnetic and X-ray absorption investigation |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
19 |
Issue |
25 |
Pages |
4382-4390 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The synthesis, electron diffraction (ED), synchrotron X-ray and neutron structure, X-ray absorption spectroscopy (XAS) and magnetic property studies of La2MnVO6 double perovskite are described. Analysis of the synchrotron powder X-ray diffraction data for La2MnVO6 indicates a disordered arrangement of Mn and V at the B-site of the perovskite structure. Absence of super-lattice reflections in the ED patterns for La2MnVO6 supports the disordered cation arrangement. Room temperature time-of-flight (TOF) neutron powder diffraction (NPD) data show no evidence of cation ordering, in corroboration with the ED and synchrotron studies (orthorhombic Pnma, a = 5.6097(3), b = 7.8837(5) and c = 5.5668(3) ; 295 K, NPD). A comparison of XAS analyses of La2TVO6 with T = Ni and Co shows T2+ formal oxidation state while the T = Mn material evidences a Mn3+ admixture into a dominantly Mn2+ ground state. V-K edge measurements manifest a mirror image behavior with a V4+ state for T = Ni and Co with a V3+ admixture arising in the T = Mn material. The magnetic susceptibility data for La2MnVO6 show ferromagnetic correlations; the observed effective moment, µeff (5.72 µB) is much smaller than the calculated moment (6.16 µB) based on the spin-only formula for Mn2+ (d5, HS) /V4+ (d1), supportive of the partly oxidized Mn and reduced V scenario (Mn3+/V3+). |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000266989800015 |
Publication Date |
2009-04-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:77367 |
Serial |
3540 |
Permanent link to this record |
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|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Mao, D.; Lookman, R.; van de Weghe, H.; Vanermen, G.; de Brucker, N.; Diels, L. |
Title |
Aqueous solubility calculation for petroleum mixtures in soil using comprehensive two-dimensional gas chromatography analysis data |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of chromatography : A |
Abbreviated Journal |
|
Volume |
1216 |
Issue |
14 |
Pages |
2873-2880 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
An assessment of aqueous solubility (leaching potential) of soil contaminations with petroleum hydrocarbons (TPH) is important in the context of the evaluation of (migration) risks and soil/groundwater remediation. Field measurements using monitoring wells often overestimate real TPH concentrations in case of presence of pure oil in the screened interval of the well. This paper presents a method to calculate TPH equilibrium concentrations in groundwater using soil analysis by high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography (HPLCGCXGC). The oil in the soil sample is divided into 79 defined hydrocarbon fractions on two GCXGC color plots. To each of these fractions a representative water solubility is assigned. Overall equilibrium water solubility of the non-aqueous phase liquid (NAPL) present in the sample and the water phase's chemical composition (in terms of the 79 fractions defined) are then calculated using Raoult's law. The calculation method was validated using soil spiked with 13 different TPH mixtures and 1 field-contaminated soil. Measured water solubilities using a column recirculation equilibration experiment agreed well to calculated equilibrium concentrations and water phase TPH composition. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000264730900020 |
Publication Date |
2008-08-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-9673 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:76414 |
Serial |
7492 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Mao, D.; Lookman, R.; van de Weghe, H.; Vanermen, G.; de Brucker, N.; Diels, L. |
Title |
Detailed analysis of petroleum hydrocarbon attenuation in biopiles by high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of chromatography : A |
Abbreviated Journal |
|
Volume |
1216 |
Issue |
9 |
Pages |
1524-1527 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Enhanced bioremediation of petroleum hydrocarbons in two biopiles was quantified by high-performance liquid chromatography (HPLC) followed by comprehensive two-dimensional gas chromatography (GCXGC). The attenuation of 34 defined hydrocarbon classes was calculated by HPLCGCXGC analysis of representative biopile samples at start-up and after 18 weeks of biopile operation. In general, a-cyclic alkanes were most efficiently removed from the biopiles, followed by monoaromatic hydrocarbons. Cycloalkanes and polycyclic aromatic hydrocarbons (PAHs) were more resistant to degradation. A-cyclic biomarkers farnesane, trimethyl-C13, norpristane, pristane and phytane dropped to only about 10% of their initial concentrations. On the other hand, C29C31 hopane concentrations remained almost unaltered after 18 weeks of biopile operation, confirming their resistance to biodegradation. They are thus reliable indicators to estimate attenuation potential of petroleum hydrocarbons in biopile processed soils. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000263610500035 |
Publication Date |
2009-01-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-9673 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:76320 |
Serial |
7769 |
Permanent link to this record |
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|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Mao, D.; Lookman, R.; van de Weghe, H.; Weltens, R.; Vanermen, G.; Brucker, N.; Diels, L. |
Title |
Estimation of ecotoxicity of petroleum hydrocarbon mixtures in soil based on HPLC-GCXGC analysis |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Chemosphere |
Abbreviated Journal |
|
Volume |
77 |
Issue |
11 |
Pages |
1508-1513 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Detailed HPLCGCXGC/FID (high performance liquid chromatography followed by comprehensive two-dimensional gas chromatography with flame-ionization detection) analysis of oil-contaminated soils was performed to interpret results of selected acute ecotoxicity assays. For the five ecotoxicity assays tested, plant seed germination and Microtox® were selected as most sensitive for evaluating ecotoxicity of the oil in the soil phase and in the leaching water, respectively. The measured toxicity for cress when testing the soil samples did not correspond to TPH concentration in the soil. A detailed chemical composition analysis of the oil contamination using HPLCGCXGC/FID allows to better predict the ecotoxicological risk and leaching potential of petroleum hydrocarbons in soil. Cress biomass production per plant was well correlated to the total aromatic hydrocarbon concentration (R2 = 0.79, n = 6), while cress seed germination was correlated (R2 = 0.82, n = 6) with total concentration of highly water-soluble aromatic hydrocarbons (HSaromatics). The observed ecotoxicity of the leaching water for Microtox-bacteria related well to calculated (based on the HPLCGCXGC/FID results) petroleum hydrocarbon equilibrium concentrations in water. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000272598700008 |
Publication Date |
2009-10-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0045-6535; 1879-1298 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:80310 |
Serial |
7935 |
Permanent link to this record |
|
|
|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Mao, D.; Lookman, R.; van de Weghe, H.; Weltens, R.; Vanermen, G.; de Brucker, N.; Diels, L. |
Title |
Combining HPLC-GCXGC, GCXGC/ToF-MS, and selected ecotoxicity assays for detailed monitoring of petroleum hydrocarbon degradation in soil and leaching water |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Environmental science and technology |
Abbreviated Journal |
|
Volume |
43 |
Issue |
20 |
Pages |
7651-7657 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
HPLC-GCXGC/FID (high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography with flame-ionization detection) and GCXGC/ToF-MS (comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry) were used to study the biodegradation of petroleum hydrocarbons in soil microcosms during 20 weeks. Two soils were studied: one spiked with fresh diesel and one field sample containing weathered diesel-like oil. Nutrient amended and unamended samples were included. Total petroleum hydrocarbon (TPH) levels in spiked soil decreased from 15000 to 7500 mg/kg d.m. and from 12000 to 4000 mg/kg d.m. in the field soil. Linear alkanes and aromatic hydrocarbons were better biodegradable (>60% degraded) than iso-alkanes; cycloalkanes were least degradable (<40%). Aromatic hydrocarbons up to three rings showed better degradability than n-alkanes. GCXGC/ToF-MS analysis of leaching water showed that initially various oxygenated hydrocarbons were produced. Compound peaks seemed to move up and rightward in the GCXGC chromatograms, indicating that more polar and heavier compounds were formed as biodegradation proceeded. Nutrient amendment can increase TPH removal rates, but had adverse effects on ecotoxicity and leaching potential in our experiment. This was explained by observed shifts in the soil microbial community. Ecotoxicity assays showed that residual TPH still inhibited cress (Lepidium sativum) seed germination, but the leaching water was no longer toxic toward luminescent bacteria (Vibrio fischeri). |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000270594900014 |
Publication Date |
2009-09-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0013-936x; 1520-5851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:79168 |
Serial |
7683 |
Permanent link to this record |
|
|
|
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Mao, D.; van de Weghe, H.; Lookman, R.; Vanermen, G.; de Brucker, N.; Diels, L. |
Title |
Resolving the unresolved complex mixture in motor oils using high-performance liquid chromatography followed by comprehensive two-dimensional gas chromatography |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Fuel |
Abbreviated Journal |
|
Volume |
88 |
Issue |
2 |
Pages |
312-318 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
High-performance liquid chromatography (HPLC) followed by comprehensive two-dimensional gas chromatography (GC×GC) was used for detailed group-type characterization of hydrocarbons present in motor oils. With conventional GC, motor oil is not well separated due to its complexity, resulting in a hump in the chromatogram: the unresolved complex mixture (UCM). With HPLC-GC×GC, motor oil hydrocarbons can be quantitatively separated into four major groups: alkanes, cycloalkanes, alkenes and aromatics. Each group can be further separated and divided by ring number or carbon number. Three selected motor oil samples were characterized by HPLC-GC×GC including two conventional motor oils and a synthetic motor oil. Using a proprietary silver-modified HPLC column, the aromatic components in motor oils were baseline separated from the aliphatic UCM and were then further separated by GC×GC based on their aromatic ring numbers. Accordingly, the aliphatic components were separated by GC×GC based on their saturated ring numbers. This paper illustrates the capabilities of HPLC-GC×GC for reliable and detailed quantitative group-type characterization of hydrocarbons present in motor oils. |
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Wos |
000262129000011 |
Publication Date |
2008-09-27 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0016-2361 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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 |
Call Number |
UA @ admin @ c:irua:75748 |
Serial |
8474 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Margu'i', E.; Queralt, I.; Van Grieken, R. |
Title |
X-ray fluorescence analysis, sample preparation for |
Type |
H1 Book chapter |
Year |
2009 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-20
T2 - Sncyclopedia of analytical chemistry / M |
Keywords |
H1 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
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Edition |
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ISBN |
978-0-471-97670-7 |
Additional Links |
UA library record |
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 |
Call Number |
UA @ admin @ c:irua:81641 |
Serial |
8765 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Marguí, E.; van Meel, K.; Van Grieken, R.; Buendía, A.; Fontás, C.; Hidalgo, M.; Queralt, I. |
Title |
Method for the determination of Pd-catalyst residues in active pharmaceutical ingredients by means of high-energy polarized-beam energy dispersive X-ray fluorescence |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
|
Volume |
81 |
Issue |
4 |
Pages |
1404-1410 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In medicinal chemistry, Pd is perhaps the most-widely utilized precious metal, as catalyst in reactions which represent key transformations toward the synthesis of new active pharmaceutical ingredients (APIs). The disadvantage of this metal-catalyzed chemistry is that expensive and toxic metal residues are invariably left bound to the desired product. Thus, stringent regulatory guidelines exist for the amount of residual Pd that a drug candidate is allowed to contain. In this work, a rapid and simple method for the determination of Pd in API samples by high-energy polarized-beam energy dispersive X-ray fluorescence spectrometry has been developed and validated according to the specification limits of current legislation (10 mg kg−1 Pd) and the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH guidelines). Sample and calibration standards preparation includes a first step of homogenization and then, in a second step, the pressing of the powdered material into pellets without any chemical treatment. The use of several synthetic calibration standards made of cellulose to simulate the API matrix appears to be an effective means to obtain reliable calibration curves with a good spread of data points over the working range. With the use of the best measuring conditions, the limit of detection (0.11 mg kg−1 Pd) as well as the limit of quantitation (0.37 mg kg−1 Pd) achieved meet rigorous requirements. The repeatability of the XRF measurement appeared to be less than 2%, while the precision of the whole method was around 7%. Trueness was evaluated by analyzing spiked API samples at the level of the specification limit and calculating the recovery factor, which was better than 95%. To study the applicability of the developed methodology for the intended purpose, three batches of the studied API were analyzed for their Pd content, and the attained results were comparable to those obtained by the daily routine method (acid digestion plus atomic spectroscopy) used in most pharmaceutical laboratories. |
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Wos |
000263319000015 |
Publication Date |
2009-01-22 |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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 |
Call Number |
UA @ admin @ c:irua:74340 |
Serial |
8220 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Martens, T.; Brok, W.J.M.; van Dijk, J.; Bogaerts, A. |
Title |
Improving dielectric barrier discharge efficiency by optimizing voltage profiles |
Type |
P1 Proceeding |
Year |
2009 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
95-98 |
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
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Place of Publication |
S.l. |
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Publication Date |
0000-00-00 |
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Additional Links |
UA library record; WoS full record; |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:85693 |
Serial |
1570 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Martens, T.; Brok, W.J.M.; van Dijk, J.; Bogaerts, A. |
Title |
On the regime transitions during the formation of an atmospheric pressure dielectric barrier glow discharge |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
42 |
Issue |
12 |
Pages |
122002,1-122002,5 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The atmospheric pressure dielectric barrier discharge in helium is a pulsed discharge in nature. If during the electrical current pulse a glow discharge is reached, then this pulse will last only a few microseconds in operating periods of sinusoidal voltage with lengths of about 10 to 100 µs. In this paper we demonstrate that right before a glow discharge is reached, the discharge very closely resembles the commonly assumed Townsend discharge structure, but actually contains some significant differing features and hence should not be considered as a Townsend discharge. In order to clarify this, we present calculation results of high time and space resolution of the pulse formation. The results indicate that indeed a maximum of ionization is formed at the anode, but that the level of ionization remains high and that the electric field at that time is significantly disturbed. Our results also show where this intermediate structure comes from. |
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Place of Publication |
London |
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Wos |
000266639300002 |
Publication Date |
2009-05-22 |
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Edition |
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ISSN |
0022-3727;1361-6463; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
21 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
Call Number |
UA @ lucian @ c:irua:76458 |
Serial |
2450 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Martens, T.; Mihailova, D.; van Dijk, J.; Bogaerts, A. |
Title |
Theoretical characterization of an atmospheric pressure glow discharge used for analytical spectrometry |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
81 |
Issue |
21 |
Pages |
9096-9108 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We have investigated the plasma processes in an atmospheric pressure glow discharge (APGD) in He used for analytical spectrometry by means of fluid and Monte Carlo (MC) simulations. Typical results include the potential and electric field distributions in the plasma, the density profiles of the various plasma species throughout the discharge, the mean electron energy, as well as the rates of the various collision processes in the plasma, and the relative importance of the different production and loss rates for the various species. The similarities and differences with low-pressure glow discharges are discussed. The main differences are a very small cathode dark space region and a large positive column as well as the dominant role of molecular ions. Some characteristic features of the APGD, such as the occurrence of the different spatial zones in the discharge, are illustrated, with links to experimental observations. |
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Place of Publication |
Washington, D.C. |
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Wos |
000276191900062 |
Publication Date |
2009-10-08 |
Series Editor |
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Edition |
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ISSN |
0003-2700;1520-6882; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 6.32; 2009 IF: 5.214 |
Call Number |
UA @ lucian @ c:irua:79554 |
Serial |
3604 |
Permanent link to this record |