| Records |
| Author |
Morozov, V.A.; Belik, A.A.; Stefanovich, S.Y.; Grebenev, V.V.; Lebedev, O.I.; Van Tendeloo, G.; Lazoryak, B.I. |
| Title |
High-temperature phase transition in the whitlockite-type phosphate Ca9In(PO4)7 |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
165 |
Issue |
2 |
Pages |
278-288 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The double phosphate Ca9In(PO4)(7) was obtained by solid-state reaction and was studied by room and high-temperature Xray powder diffraction, electron diffraction, high-resolution electron microscopy, second-harmonic generation (SHG) technique, differential scanning calorimetry, dielectric and conductivity measurements. The beta-Ca9In(PO4)(7) room-temperature phase is related to the mineral whitlockite and is similar to beta-Ca-3(PO4)(2). It has space group R (3) over barc, with unit cell parameters: a = 10.4008(1) Angstrom, c = 37.272(1) Angstrom, Z = 6. The structure was refined by the Rietveld method (R-wp = 4.69, R-I = 1.81). A reversible first-order beta <----> beta' phase transition of the ferroelectric type with T-c = 902 K is revealed by SHG, differential scanning calorimetry and dielectric measurements. The centrosymmetric beta'-Ca9In(PO4)(7) (973 K) has space group R (3) over barc, a = 10.4611(2) Angstrom, c = 37.874 (1) Angstrom (R-wp = 4.27, R-I = 4.11). Compared to the low-temperature beta-Ca9In(PO4)(7) structure, beta'-Ca9In(PO4)(7) can be described as an orientational disordering of the P1O(4) tetrahedra together with a calcium disordering on the M3 site. (C) 2002 Elsevier Science (USA). |
| 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 |
000175916000010 |
Publication Date |
2002-10-06 |
| 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 |
| Impact Factor |
2.299 |
Times cited  |
57 |
Open Access |
|
| Notes |
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Approved |
Most recent IF: 2.299; 2002 IF: 1.671 |
| Call Number |
UA @ lucian @ c:irua:94926 |
Serial |
1467 |
| Permanent link to this record |
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| |
| Author |
Bogaerts, A.; Gijbels, R. |
| Title |
Hybrid Monte-Carlo-fluid modeling network for an argon/hydrogen direct current glow discharge |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
Spectrochim Acta B |
| Volume |
57 |
Issue |
|
Pages |
1071-1099 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| 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 |
Oxford |
Editor |
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| Language |
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Wos |
000177673200006 |
Publication Date |
2002-09-17 |
| 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; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.241 |
Times cited |
68 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.241; 2002 IF: 2.695 |
| Call Number |
UA @ lucian @ c:irua:40182 |
Serial |
1527 |
| Permanent link to this record |
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| Author |
Tadić, M.; Peeters, F.M.; Janssens, K.L. |
| Title |
Effect of isotropic versus anisotropic elasticity on the electronic structure of cylindrical InP/In0.49Ga0.51P self-assembled quantum dots |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
65 |
Issue |
16 |
Pages |
165333-13 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The electronic structure of disk-shaped InP/InGaP self-assembled quantum dots is calculated within the effective-mass theory. The strain-dependent 6x6 multiband Hamiltonian for the valence band is simplified into an axially symmetric form. Both the continuum mechanical model, discretized by finite elements, and the isotropic model are used to calculate the strain distribution and their results are critically compared. The dependence of the electron and the hole energy levels on the dimensions of the quantum dot is investigated. We found that both the electron and hole energies are underestimated if the strain distribution is calculated by the isotropic elasticity theory. The agreement between the electron energies for the two approaches is better for thinner quantum dots. The heavy holes are confined inside the quantum dot, while the light holes are located outside the disk, but confined by the strain field near the edge of the disk periphery. We found that the (h) over bar /2 hole ground state crosses the 3 (h) over bar /2 ground state when the height of the quantum dot increases and becomes the ground state for sufficiently thick quantum disks. The higher hole levels exhibit both crossings between the states of the different parity and anticrossings between the states of the same parity. |
| 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 |
000175325000097 |
Publication Date |
2002-07-27 |
| 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 |
0163-1829;1095-3795; |
ISBN |
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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; 2002 IF: NA |
| Call Number |
UA @ lucian @ c:irua:103361 |
Serial |
819 |
| Permanent link to this record |
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| Author |
Tadić, M.; Peeters, F.M.; Janssens, K.L.; Korkusinski, M.; Hawrylak, P. |
| Title |
Strain and band edges in single and coupled cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
92 |
Issue |
10 |
Pages |
5819-5829 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
A comparative study is made of the strain distribution in cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots as obtained from isotropic elasticity theory, the anisotropic continuum mechanical model, and from atomistic calculations. For the isotropic case, the recently proposed approach [J. H. Davies, J. Appl. Phys. 84, 1358 (1998)] is used, while the finite-element method, the valence force field method, and Stillinger-Weber potentials are employed to calculate the strain in anisotropic structures. We found that all four methods result in strain distributions of similar shapes, but with notable quantitative differences inside the dot and near the disk-matrix boundary. The variations of the diagonal strains with the height of the quantum dot, with fixed radius, as calculated from all models, are almost linear. Furthermore, the energies of the band edges in the two types of quantum dots are extracted from the multiband effective-mass theory by inserting the strain distributions as obtained by the four models. We demonstrated that all strain models produce effective potentials for the heavy and light holes which agree very well inside the dot. A negligible anisotropy of all normal strains in the (x,y) plane is found, which, providing the axial symmetry of the kinetic part of the multiband effective-mass Hamiltonian, justifies the use of the axial approximation. Strain propagation along the vertical direction is also considered with the aim to study the influence of strain on the electron coupling in stacks of quantum dots. We found that the interaction between the strain fields of the individual quantum dots makes the effective quantum wells for the electrons in the conduction band shallower, thereby counteracting the quantum mechanical coupling. (C) 2002 American Institute of Physics. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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| Language |
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Wos |
000178987200036 |
Publication Date |
2002-11-07 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
73 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.068; 2002 IF: 2.281 |
| Call Number |
UA @ lucian @ c:irua:103327 |
Serial |
3164 |
| Permanent link to this record |
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| Author |
Milošević, M.V.; Yampolskii, S.V.; Peeters, F.M. |
| Title |
Magnetic pinning of vortices in a superconducting film: the (anti)vortex-magnetic dipole interaction energy in the London approximation |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
66 |
Issue |
|
Pages |
174519,1-13 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| 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 |
Lancaster, Pa |
Editor |
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| Language |
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Wos |
000179611700103 |
Publication Date |
2002-11-26 |
| 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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
76 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.836; 2002 IF: NA |
| Call Number |
UA @ lucian @ c:irua:44982 |
Serial |
1887 |
| Permanent link to this record |
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| Author |
Wang, X.F.; Vasilopoulos, P.; Peeters, F.M. |
| Title |
Spin-current modulation and square-wave transmission through periodically stubbed electron waveguides |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
65 |
Issue |
16 |
Pages |
165217 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Ballistic spin transport through waveguides, with symmetric or asymmetric double stubs attached to them periodically, is studied systematically in the presence of a weak spin-orbit coupling that makes the electrons precess. By an appropriate choice of the waveguide length and of the stub parameters injected spin-polarized electrons can be blocked completely and the transmission shows a periodic and nearly-square-type behavior, with values 1 and 0, with wide gaps when only one mode is allowed to propagate in the waveguide. A similar behavior is possible for a certain range of the stub parameters even when two modes can propagate in the waveguide and the conductance is doubled. Such a structure is a good candidate for establishing a realistic spin transistor. A further modulation of the spin current can be achieved by inserting defects in a finite-number stub superlattice. Finite-temperature effects on the spin conductance are also considered. |
| 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 |
000175325000061 |
Publication Date |
2002-07-27 |
| 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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
112 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.836; 2002 IF: NA |
| Call Number |
UA @ lucian @ c:irua:95128 |
Serial |
3082 |
| Permanent link to this record |
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| Author |
Dams, M.; Drijkoningen, L.; Pauwels, B.; Van Tendeloo, G.; de Vos, D.E.; Jacobs, P.A. |
| Title |
Pd-zeolites as heterogeneous catalysts in heck chemistry |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Journal of catalysis |
Abbreviated Journal |
J Catal |
| Volume |
209 |
Issue |
1 |
Pages |
225-236 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| 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 |
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Editor |
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| Language |
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Wos |
000176501100027 |
Publication Date |
2002-10-06 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0021-9517; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.844 |
Times cited |
157 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.844; 2002 IF: 3.118 |
| Call Number |
UA @ lucian @ c:irua:54844 |
Serial |
2567 |
| Permanent link to this record |
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| Author |
Baelus, B.J.; Peeters, F.M. |
| Title |
Dependence of the vortex configuration on the geometry of mesoscopic flat samples |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
65 |
Issue |
10 |
Pages |
104515-12 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The influence of the geometry of a thin superconducting sample on the penetration of the magnetic field lines and the arrangement of vortices are investigated theoretically. We compare the vortex state of superconducting disks, squares, and triangles with the same surface area having nonzero thickness. The coupled nonlinear Ginzburg-Landau equations are solved self-consistently and the important demagnetization effects are taken into account. We calculate and compare quantities such as the free energy, the magnetization, the Cooper-pair density, the magnetic field distribution, and the superconducting current density for the three geometries. For given vorticity the vortex lattice is different for the three geometries, i.e., it tries to adapt to the geometry of the sample. This also influences the stability range of the different vortex states. For certain magnetic field ranges we found a coexistence of a giant vortex placed in the center and single vortices towards the corners of the sample. The H-T phase diagram is obtained for the three investigated geometries and we found that the critical magnetic field is substantially enhanced for the triangle geometry. |
| 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 |
000174548300111 |
Publication Date |
2002-07-27 |
| 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 |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
189 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.836; 2002 IF: NA |
| Call Number |
UA @ lucian @ c:irua:102833 |
Serial |
645 |
| Permanent link to this record |
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| |
| Author |
Bogaerts, A.; Neyts, E.; Gijbels, R.; van der Mullen, J. |
| Title |
Gas discharge plasmas and their applications |
Type |
A1 Journal article |
| Year |
2002 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
Spectrochim Acta B |
| Volume |
57 |
Issue |
|
Pages |
609-658 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| 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 |
Oxford |
Editor |
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| Language |
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Wos |
000175779700001 |
Publication Date |
2002-10-15 |
| 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; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.241 |
Times cited |
462 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.241; 2002 IF: 2.695 |
| Call Number |
UA @ lucian @ c:irua:40181 |
Serial |
1317 |
| Permanent link to this record |
