Records |
Author |
Das, P.; Koblischka, M.R.; Turner, S.; Van Tendeloo, G.; Wolf, T.; Jirsa, M.; Hartmann, U. |
Title |
Direct observation of nanometer-scale pinning sites in (Nd0.33Eu0.20Gd0.47)Ba2Cu3O7-\delta single crystals |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
Volume |
83 |
Issue |
3 |
Pages |
37005,1-37005,4 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report on the observation of self-organized stripe-like structures on the as-grown surface and in the bulk of (Nd,Eu,Gd)Ba2Cu3Oy single crystals. The periodicity of the stripes on the surface lies between 500800 nm. These are possibly the growth steps of the crystal. Transmission electron microscopy investigations revealed stripes of periodicity in the range of 2040 nm in the bulk. From electron back scattered diffraction investigations, no crystallographic misorientation due to the nanostripes has been found. Scanning tunneling spectroscopic experiments revealed nonsuperconducting regions, running along twin directions, which presumably constitute strong pinning sites. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Paris |
Editor |
|
Language |
|
Wos |
000259022600032 |
Publication Date |
2008-07-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.957 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.957; 2008 IF: 2.203 |
Call Number |
UA @ lucian @ c:irua:76496 |
Serial |
719 |
Permanent link to this record |
|
|
|
Author |
Alexandrov, A.L.; Schweigert, I.V.; Peeters, F.M. |
Title |
A non-Maxwellian kinetic approach for charging of dust particles in discharge plasmas |
Type |
A1 Journal article |
Year |
2008 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
10 |
Issue |
|
Pages |
093025,1-093025,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Nanoparticle charging in a capacitively coupled radio frequency discharge in argon is studied using a particle in cell Monte Carlo collisions method. The plasma parameters and dust potential were calculated self-consistently for different unmovable dust profiles. A new method for definition of the dust floating potential is proposed, based on the information about electron and ion energy distribution functions, obtained during the kinetic simulations. This approach provides an accurate balance of the electron and ion currents on the dust particle surface and allows us to precisely calculate the dust floating potential. A comparison of the obtained floating potentials with the results of the traditional orbital motion limit (OML) theory shows that in the presence of the ion resonant charge exchange collisions, even when the OML approximation is valid, its results are correct only in the region of a weak electric field, where the ion drift velocity is much smaller than the thermal one. With increasing ion drift velocity, the absolute value of the calculated dust potential becomes significantly smaller than the theory predicts. This is explained by a non-Maxwellian shape of the ion energy distribution function for the case of fast ion drift. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000259615700004 |
Publication Date |
2008-09-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2008 IF: 3.440 |
Call Number |
UA @ lucian @ c:irua:76519 |
Serial |
2348 |
Permanent link to this record |
|
|
|
Author |
Doria, M.M.; Brandt, E.H.; Peeters, F.M. |
Title |
Magnetization of a superconducting film in a perpendicular magnetic field |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
5 |
Pages |
0544047,1-054407,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
With large thin superconducting films in a perpendicular magnetic field, the usual definition and calculation of the magnetization M via currents or as the difference of two fields fail, since the spatially averaged magnetic field in the film coincides with the uniform applied field and the demagnetization factor is unity. The definition of M as field-derivative of the free energy, however, still works in this limit. We generalize the virial theorem, previously derived for infinite bulk superconductors, to infinitely extended films of arbitrary thickness. An expression for M is obtained that indeed reproduces the M computed from the field derivative of the free energy. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000259368200063 |
Publication Date |
2008-08-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:76525 |
Serial |
1895 |
Permanent link to this record |
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|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Superconducting nanofilms: Andreev-type states induced by quantum confinement |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
5 |
Pages |
054505,1-054505,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
Abstract |
Quantum confinement of the transverse electron motion is the major effect governing the superconducting properties of high-quality metallic nanofilms, leading to a nonuniform transverse distribution of the superconducting condensate. In this case the order parameter can exhibit significant local enhancements due to these quantum-size effects and, consequently, quasiparticles have lower energies when they avoid the local enhancements of the pair condensate. Such excitations can be considered as new Andreev-type quasiparticles but now induced by quantum confinement. By numerically solving the Bogoliubovde Gennes equations and using Anderson's approximate solution to these equations, we: (a) formulate a criterion for such new Andreev-type states (NATS) and (b) study their effect on the superconducting characteristics in metallic nanofilms. We also argue that nanofilms made of low-carrier-density materials, e.g., of superconducting semiconductors, can be a more optimal choice for the observations of NATS and other quantum-size superconducting effects. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000259368200109 |
Publication Date |
2008-08-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:76526 |
Serial |
3356 |
Permanent link to this record |
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|
|
Author |
Schweigert, I.V.; Alexandrov, A.L.; Ariskin, D.A.; Peeters, F.M.; Stefanović, I.; Kovačević, E.; Berndt, J.; Winter, J. |
Title |
Effect of transport of growing nanoparticles on capacitively coupled rf discharge dynamics |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
78 |
Issue |
2 |
Pages |
026410,1-026410,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present experimental and numerical studies of the properties of a capacitively coupled 13.56 MHz discharge in a mixture of Ar and C2H2 with growing nanosize particles. It is found that at the initial stage of the growth, nanoparticles are accumulated near the sheath-plasma boundaries, where the ionization by electrons is maximal. The nanoparticles suppress the ionization due to the absorbing fast electrons and stimulate a quick change of the plasma parameters followed by a transition between different modes of discharge operation. At that moment the peaked distribution of the dust particles transforms into a flat one. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000259263700071 |
Publication Date |
2008-08-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
36 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.366; 2008 IF: 2.508 |
Call Number |
UA @ lucian @ c:irua:76552 |
Serial |
851 |
Permanent link to this record |
|
|
|
Author |
Zhao, H.-W.; Zha, G.-Q.; Zhou, S.-P.; Peeters, F.M. |
Title |
Long-range Coulomb repulsion effect on a charged vortex in high-temperature superconductors with competing d-wave and antiferromagnetic orders |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
6 |
Pages |
064505,1-064505,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Vortex charges in high-temperature superconductor (HTS) are studied by solving the Bogoliubovde Gennes equations based on a model Hamiltonian with antiferromagnetic (AF) and d-wave orders in the presence of the long-range Coulomb repulsion. For a sufficient strength of the AF order, the negative vortex charge is found. A sign change between negative and positive may occur by tuning the long-range Coulomb repulsion strength or the doping parameter. Recent NMR experiments are hopefully understood. We show that the charged vortex can induce a spin-orbit coupling that is important for superconductors with a short coherence length and a large value of the energy gap over the Fermi-level ratio. Fractional flux quanta are possible for HTS. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000259264900084 |
Publication Date |
2008-08-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:76553 |
Serial |
1837 |
Permanent link to this record |
|
|
|
Author |
Nowak, M.P.; Szafran, B.; Peeters, F.M. |
Title |
Manipulation of two-electron states by the electric field in stacked self-assembled dots |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
20 |
Issue |
39 |
Pages |
395225,1-395225,14 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A pair of electrons in vertically stacked self-assembled quantum dots is studied and the singlettriplet energy splitting is calculated in an external electric field using the configuration-interaction method. We show that for double quantum dots the dependence of the singlet energy levels on the electric field involves multiple avoided crossings of three energy levels. The exchange interaction, i.e., the energy difference of the lowest triplet and lowest singlet states, can be tuned by an electric field in a wide range of several tens of meV. For electric fields exceeding a threshold value the exchange interaction becomes a linear function of the field when the two electrons in the singlet state start to occupy the same dot. We also consider non-symmetric confinement, non-perfectly aligned dots, in horizontal as well as vertical field orientation. In a stack of three vertically coupled dots the depth of the confinement in the central dot can be used to enhance the exchange interaction. For a deeper central dot the dependence of the exchange interaction on the electric field is anomalousit initially decreases when the field is applied in both directions parallel and antiparallel to the axis of the stack. Such a behavior is never observed for a pair of quantum dots. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000259034200032 |
Publication Date |
2008-09-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2008 IF: 1.900 |
Call Number |
UA @ lucian @ c:irua:76592 |
Serial |
1940 |
Permanent link to this record |
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|
|
Author |
Lepoittevin, C.; Malo, S.; Nguyen, N.; Hebert, S.; Van Tendeloo, G.; Hervieu, M. |
Title |
A layered iron-rich 2234-type with a mixed valence of iron: the ferrimagnetic Tl-doped Fe2(Sr2-\varepsilonTl\varepsilon)Sr3Fe4O14.65 |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
20 |
Issue |
20 |
Pages |
6468-6476 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A new Tl-doped strontium ferrite Fe2(Sr2-Tl)Sr3Fe4O14.65, with an original structure, has been synthesized and structurally characterized by powder X-ray diffraction and transmission electron microscopy. The TGA and Mssbauer studies evidence a mixed valence of iron. The structure exhibits a commensurate modulation, with a F-type subcell a ≈ b ≈ 5.4 Å (≈ ap√2), c ≈ 42 Å with a modulation vector q = αa* with α = 0.4. The supercell parameters have been refined as a= 27.1101(8) Å, b= 5.5187(2) Å and c= 42.0513(9) Å, in the space group Fmmm. The electron diffraction and electron microscopy data of this novel ferrite show that it can be described as a FeTl-2234-type structure corresponding to the intergrowth of a quadruple perovskite slice [(SrFeO2.8)4], with a complex rock salt related slice [Fe2(Sr2-Tl)O3.4]∞, built up of one double iron layer [Fe2O2.4] sandwiched between two [SrO] layers. The HRTEM images show that the oxygen atoms and vacancies are randomly distributed in the perovskite layers while the HAADF STEM images evidence the absence of Tl segregation in the matrix. Fe2(Sr2-Tl)Sr3Fe4O14.65 exhibits a very large value of χ (11emu/mol) at 5 K, which remains large at 400 K; the M(H) loop presents a shape characteristic of ferrimagnetism, with a large coercive field of 0.3 T. The value of magnetization saturates at 400 K at 0.68 μB/Fe. At 10 K, the value of magnetization reaches a maximum of 2 μB/Fe. The resistivity presents a semiconducting-like behavior, with ρ 800 Ω·cm at 300 K. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000260254400030 |
Publication Date |
2008-09-25 |
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 |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2008 IF: 5.046 |
Call Number |
UA @ lucian @ c:irua:76671 |
Serial |
1804 |
Permanent link to this record |
|
|
|
Author |
Bogaerts, A.; Bultinck, E.; Eckert, M.; Georgieva, V.; Mao, M.; Neyts, E.; Schwaederlé, L. |
Title |
Computer modeling of plasmas and plasma-surface interactions |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Plasma processes and polymers |
Abbreviated Journal |
Plasma Process Polym |
Volume |
6 |
Issue |
5 |
Pages |
295-307 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, an overview is given of different modeling approaches used for describing gas discharge plasmas, as well as plasma-surface interactions. A fluid model is illustrated for describing the detailed plasma chemistry in capacitively coupled rf discharges. The strengths and limitations of Monte Carlo simulations and of a particle-in-cell-Monte Carlo collisions model are explained for a magnetron discharge, whereas the capabilities of a hybrid Monte Carlo-fluid approach are illustrated for a direct current glow discharge used for spectrochemical analysis of materials. Finally, some examples of molecular dynamics simulations, for the purpose of plasma-deposition, are given. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000266471800003 |
Publication Date |
2009-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1612-8850;1612-8869; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.846 |
Times cited |
18 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.846; 2009 IF: 4.037 |
Call Number |
UA @ lucian @ c:irua:76833 |
Serial |
461 |
Permanent link to this record |
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|
|
Author |
Smeulders, G.; Meynen, V.; van Baelen, G.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Maes, B.U.W.; Cool, P. |
Title |
Rapid microwave-assisted synthesis of benzene bridged periodic mesoporous organosilicas |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
19 |
Issue |
19 |
Pages |
3042-3048 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA); Organic synthesis (ORSY) |
Abstract |
Following extended use in organic chemistry, microwave-assisted synthesis is gaining more importance in the field of inorganic chemistry, especially for the synthesis of nanoporous materials. It offers some major advantages such as a significant shortening of the synthesis time and an improved promotion of nucleation. In the research here reported, microwave technology is applied for the synthesis of benzene bridged PMOs (periodic mesoporous organosilicas). PMOs are one of the latest innovations in the field of hybrid ordered mesoporous materials and have attracted much attention because of their feasibility in electronics, catalysis, separation and sorption applications. The different synthesis steps (stirring, aging and extraction) of the classical PMO synthesis are replaced by microwave-assisted synthesis steps. The characteristics of the as-synthesized materials are evaluated by X-ray diffraction, N2-sorption, thermogravimetric analysis, scanning- and transmission electron microscopy. The microwave-assisted synthesis drastically reduces the synthesis time by more than 40 hours without any loss in structural properties, such as mesoscale and molecular ordering. The porosity of the PMO materials has even been improved by more than 25%. Moreover, the number of handling/transfer steps and amounts of chemicals and waste are drastically reduced. The study also shows that there is a clear time (1 to 3 hours) and temperature frame (373 K to 403 K) wherein synthesis of benzene bridged PMO is optimal. In conclusion, the microwave-assisted synthesis pathway allows an improved material to be obtained in a more economical way i.e. a much shorter time with fewer chemicals and less waste. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000265919300024 |
Publication Date |
2009-03-17 |
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 |
20 |
Open Access |
|
Notes |
Fwo; Iwt |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:76844 |
Serial |
2810 |
Permanent link to this record |
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|
|
Author |
Milošević, M.M.; Tadić, M.; Peeters, F.M. |
Title |
Effects of lateral asymmetry on electronic structure of strained semiconductor nanorings in a magnetic field |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
19 |
Issue |
45 |
Pages |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The influence of lateral asymmetry on the electronic structure and optical transitions in elliptical strained InAs nanorings is analyzed in the presence of a perpendicular magnetic field. Two-dimensional rings are assumed to have elliptical inner and outer boundaries oriented in mutually orthogonal directions. The influence of the eccentricity of the ring on the energy levels is analyzed. For large eccentricity of the ring, we do not find any AharonovBohm effect, in contrast to circular rings. Rather, the single-particle states of the electrons and the holes are localized as in two laterally coupled quantum dots formed in the lobes of the nanoring. Our work indicates that the control of shape is important for the existence of the AharonovBohm effect in semiconductor nanorings. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000259922000016 |
Publication Date |
2008-10-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.44; 2008 IF: 3.446 |
Call Number |
UA @ lucian @ c:irua:76874 |
Serial |
865 |
Permanent link to this record |
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|
|
Author |
Yang, W.; Nelissen, K.; Kong, M.; Zeng, Z.; Peeters, F.M. |
Title |
Structure of binary colloidal systems confined in a quasi-one-dimensional channel |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
79 |
Issue |
4 |
Pages |
041406,1-041406,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The structural properties of a binary colloidal quasi-one-dimensional system confined in a narrow channel are investigated through modified Monte Carlo simulations. Two species of particles with different magnetic moment interact through a repulsive dipole-dipole force are confined in a quasi-one-dimensional channel. The impact of three decisive parameters (the density of particles, the magnetic-moment ratio, and the fraction between the two species) on the transition from disordered phase to crystal-like phases and the transitions among the different mixed phases are summarized in a phase diagram. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265941300077 |
Publication Date |
2009-04-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.366; 2009 IF: 2.400 |
Call Number |
UA @ lucian @ c:irua:77021 |
Serial |
3308 |
Permanent link to this record |
|
|
|
Author |
Tadić, M.; Peeters, F.M. |
Title |
Excitonic properties of strained triple quantum-ring molecules |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
15 |
Pages |
153305,1-153305,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The tunneling coupling in three vertically stacked (In,Ga)As/GaAs quantum rings is investigated. With increasing inter-ring separation (d), we find that the nonuniform strain results into a crossing of the lowest-energy electron states. Strain is also responsible for an increase in the ground electron energy above the level in the single quantum ring. The ground hole energy level exhibits decrease when d decreases, which is typical for antibonding states in an unstrained structure. These effects lead to a local maximum in the dependence of the ground-state exciton energy on d. Our theoretical results compare well with recent photoluminescence measurements but deviate considerably from the calculations for flat bands in quantum-ring molecules. We conclude that the nonuniform character of the strain distribution gives rise to a peculiar exciton hybridization in self-assembled quantum-ring molecules. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265944200018 |
Publication Date |
2009-04-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77024 |
Serial |
1123 |
Permanent link to this record |
|
|
|
Author |
Barbier, M.; Vasilopoulos, P.; Peeters, F.M.; Pereira, J.M. |
Title |
Bilayer graphene with single and multiple electrostatic barriers: band structure and transmission |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
15 |
Pages |
155402,1-155402,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We evaluate the electronic transmission and conductance in bilayer graphene through a finite number of potential barriers. Further, we evaluate the dispersion relation in a bilayer graphene superlattice with a periodic potential applied to both layers. As a model we use the tight-binding Hamiltonian in the continuum approximation. For zero bias the dispersion relation shows a finite gap for carriers with zero momentum in the direction parallel to the barriers. This is in contrast to single-layer graphene where no such gap was found. A gap also appears for a finite bias. Numerical results for the energy spectrum, conductance, and the density of states are presented and contrasted with those pertaining to single-layer graphene. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265944200091 |
Publication Date |
2009-04-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
74 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77025 |
Serial |
235 |
Permanent link to this record |
|
|
|
Author |
Masir, M.R.; Matulis, A.; Peeters, F.M. |
Title |
Quasibound states of Schrödinger and Dirac electrons in a magnetic quantum dot |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
15 |
Pages |
155451,1-155451,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The properties of a two-dimensional electron are investigated in the presence of a circular step magnetic-field profile. Both electrons with parabolic dispersion as well as Dirac electrons with linear dispersion are studied. We found that in such a magnetic quantum dot no electrons can be confined. Nevertheless close to the Landau levels quasibound states can exist with a rather long lifetime. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265944200140 |
Publication Date |
2009-04-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
55 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77026 |
Serial |
2800 |
Permanent link to this record |
|
|
|
Author |
Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M. |
Title |
Neutral shallow donors near a metallic interface |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
Volume |
40 |
Issue |
4/5 |
Pages |
753-755 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of a metallic gate on the bound states of a shallow donor located near the gate is studied. We calculate the energy spectrum as a function of the distance between the metallic gate and the donor and find an anti-crossing behavior in the energy levels for certain distances. We show how a transverse electric field can tune the average position of the electron with respect to the metallic gate and the impurity. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Luton |
Editor |
|
Language |
|
Wos |
000265870200024 |
Publication Date |
2009-02-04 |
Series Editor |
|
Series Title |
|
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 |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
Call Number |
UA @ lucian @ c:irua:77029 |
Serial |
2296 |
Permanent link to this record |
|
|
|
Author |
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 |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Luton |
Editor |
|
Language |
|
Wos |
000265870200058 |
Publication Date |
2008-12-26 |
Series Editor |
|
Series Title |
|
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 |
|
|
|
Author |
Bharathy, M.; Gemmill, W.R.; Fox, A.H.; Darriet, J.; Smith, M.D.; Hadermann, J.; Remy, M.S.; zur Loye, H.-C. |
Title |
Synthesis and magnetic properties of rare earth ruthenates, Ln5Ru2O12 (Ln=Pr, Nd, SmTb) |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
Volume |
182 |
Issue |
5 |
Pages |
1164-1170 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Single crystals of Ln5Ru2O12 (Ln=Pr, Nd, SmTb) were grown out of either NaOH or KOH fluxes in sealed silver tubes. The crystals of all the phases were observed to be twinned as confirmed by TEM studies. The series crystallize in the C2/m monoclinic system with lattice parameters, a=12.4049(4)12.7621(6) Å, b=5.8414(2)5.9488(3) Å, c=7.3489(2)7.6424(4) Å, β=107.425(3)107.432(2)° and Z=2. The crystal structure is isotypic with the defect/disorder model of Ln5Re2O12 (Ln = Y, Gd) and consists of one dimensional edge shared RuO6 octahedral chains separated by a two dimensional LnOx polyhedral framework. Magnetic measurements indicate paramagnetic and antiferromagnetic behavior for Ln=Nd, SmGd and Ln=Tb, respectively. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000265893700027 |
Publication Date |
2009-02-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.299 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.299; 2009 IF: 2.340 |
Call Number |
UA @ lucian @ c:irua:77052 |
Serial |
3433 |
Permanent link to this record |
|
|
|
Author |
Dubourdieu, C.; Rauwel, E.; Roussel, H.; Ducroquet, F.; Hollaender, B.; Rossell, M.; Van Tendeloo, G.; Lhostis, S.; Rushworth, S. |
Title |
Addition of yttrium into HfO2 films: microstructure and electrical properties |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of vacuum science and technology: A: vacuum surfaces and films |
Abbreviated Journal |
J Vac Sci Technol A |
Volume |
27 |
Issue |
3 |
Pages |
503-514 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The cubic phase of HfO2 was stabilized by addition of yttrium in thin films grown on Si/SiO2 by metal-organic chemical vapor deposition. The cubic phase was obtained for contents of 6.5 at. % Y or higher at a temperature as low as 470 °C. The complete compositional range (from 1.5 to 99.5 at. % Y) was investigated. The crystalline structure of HfO2 was determined from x-ray diffraction, electron diffraction, and attenuated total-reflection infrared spectroscopy. For cubic films, the continuous increase in the lattice parameter indicates the formation of a solid-solution HfO2Y2O3. As shown by x-ray photoelectron spectroscopy, yttrium silicate is formed at the interface with silicon; the interfacial layer thickness increases with increasing yttrium content and increasing film thickness. The dependence of the intrinsic relative permittivity r as a function of Y content was determined. It exhibits a maximum of ~30 for ~8.8 at. % Y. The cubic phase is stable upon postdeposition high-temperature annealing at 900 °C under NH3. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000265739100016 |
Publication Date |
2009-05-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0734-2101; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.374 |
Times cited |
29 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.374; 2009 IF: 1.297 |
Call Number |
UA @ lucian @ c:irua:77054 |
Serial |
58 |
Permanent link to this record |
|
|
|
Author |
Hadermann, J.; Abakumov, A.M.; Van Rompaey, S.; Mankevich, A.S.; Korsakov, I.E. |
Title |
Comment on ALaMn2O6-y (A = K, Rb): novel ferromagnetic manganites exhibiting negative giant magnetoresistance |
Type |
Editorial |
Year |
2009 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
21 |
Issue |
9 |
Pages |
2000-2001 |
Keywords |
Editorial; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000265781000036 |
Publication Date |
2009-04-14 |
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 |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 9.466; 2009 IF: 5.368 |
Call Number |
UA @ lucian @ c:irua:77055 |
Serial |
411 |
Permanent link to this record |
|
|
|
Author |
Kips, R.; Pidduck, A.J.; Houlton, M.R.; Leenaers, A.; Mace, J.D.; Marie, O.; Pointurier, F.; Stefaniak, E.A.; Taylor, P.D.P.; van den Berghe, S.; van Espen, P.; Van Grieken, R.; Wellum, R. |
Title |
Determination of fluorine in uranium oxyfluoride particles as an indicator of particle age |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
|
Volume |
64 |
Issue |
3 |
Pages |
199-207 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3) |
Abstract |
As swipe samples from enrichment activities typically contain uranium particles with a detectable amount of fluorine, the question was raised whether the analysis of fluorine in particles could complement the information on the uranium isotope ratios. For this, uranium oxyfluoride particles were prepared from the controlled hydrolysis of uranium hexafluoride (UF6). The relative amount of fluorine was characterized by scanning electron microscopy combined with energy-dispersive X-ray spectrometry (SEM-EDX), as well as ion-microprobe secondary ion mass spectrometry (IM-SIMS). Of particular interest was the assessment of the reduction of the amount of fluorine over time, and after exposure to UV-light and high temperatures. Micro-Raman spectrometry (MRS) was applied to look for differences in molecular structure between these various sample types. Both SEM-EDX and IM-SIMS showed a general reduction of the fluorine-to-uranium ratio after 12 years of storage. The exposure to UV-light and high temperatures was found to have accelerated the loss of fluorine. A distinct peak at 865 cm− 1 Raman shift was detected for the majority of particles analyzed by MRS. For the particles that were heat-treated, the Raman spectra were similar to the spectrum of U3O8. Although often large variations were observed between particles from the same sample, the three particle measurement techniques (IM-SIMS, SEM-EDX and MRS) showed some consistent trends. They therefore appear promising in terms of the ability to place bounds on particle age, as well as shedding light on the complex processes involved in UO2F2 particle ageing. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000265755600002 |
Publication Date |
2008-12-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0584-8547; 1873-3565 |
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:77057 |
Serial |
7780 |
Permanent link to this record |
|
|
|
Author |
Van Tendeloo, G.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V. |
Title |
Advanced electron microscopy and its possibilities to solve complex structures: application to transition metal oxides |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
19 |
Issue |
18 |
Pages |
2660-2670 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Design and optimization of materials properties can only be performed through a thorough knowledge of the structure of the compound. In this feature article we illustrate the possibilities of advanced electron microscopy in materials science and solid state chemistry. The different techniques are briefly discussed and several examples are given where the structures of complex oxides, often with a modulated structure, have been solved using electron microscopy. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000265740600002 |
Publication Date |
2009-02-04 |
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 |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:77065 |
Serial |
68 |
Permanent link to this record |
|
|
|
Author |
Beyers, E.; Biermans, E.; Ribbens, S.; de Witte, K.; Mertens, M.; Meynen, V.; Bals, S.; Van Tendeloo, G.; Vansant, E.F.; Cool, P. |
Title |
Combined TiO2/SiO2 mesoporous photocatalysts with location and phase controllable TiO2 nanoparticles |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
Appl Catal B-Environ |
Volume |
88 |
Issue |
3/4 |
Pages |
515-524 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Combined TiO2/SiO2 mesoporous materials were prepared by deposition of TiO2 nanoparticles synthesised via the acid-catalysed solgel method. In the first synthesis step a titania solution is prepared, by dissolving titaniumtetraisopropoxide in nitric acid. The influences of the initial titaniumtetraisopropoxide concentration and the temperature of dissolving on the final structural properties were investigated. In the second step of the synthesis, the titania nanoparticles were deposited on a silica support. Here, the influence of the temperature during deposition was studied. The depositions were carried out on two different mesoporous silica supports, SBA-15 and MCF, leading to substantial differences in the catalytic and structural properties. The samples were analysed with N2-sorption, X-ray diffraction (XRD), electron probe microanalysis (EPMA) and transmission electron microscopy (TEM) to obtain structural information, determining the amount of titania, the crystal phase and the location of the titania particles on the mesoporous material (inside or outside the mesoporous channels). The structural differences of the support strongly determine the location of the nanoparticles and the subsequent photocatalytic activity towards the degradation of rhodamine 6G in aqueous solution under UV irradiation. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000266513400032 |
Publication Date |
2008-10-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0926-3373; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.446 |
Times cited |
69 |
Open Access |
|
Notes |
Goa-Bof; Fwo |
Approved |
Most recent IF: 9.446; 2009 IF: 5.252 |
Call Number |
UA @ lucian @ c:irua:77150 |
Serial |
403 |
Permanent link to this record |
|
|
|
Author |
Bencs, L.; Krata, A.; Horemans, B.; Buczyńska, A.J.; Dirtu, A.C.; Godoi, A.F.L.; Godoi, R.H.M.; Potgieter-Vermaak, S.; Van Grieken, R. |
Title |
Atmospheric nitrogen fluxes at the Belgian coast: 2004-2006 |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Atmospheric environment : an international journal |
Abbreviated Journal |
|
Volume |
43 |
Issue |
24 |
Pages |
3786-3798 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Daily and seasonal variations in dry and wet atmospheric nitrogen fluxes have been studied during four campaigns between 2004 and 2006 at a coastal site of the Southern North Sea at De Haan (Belgium) located at coordinates of 51.1723° N and 3.0369° E. Concentrations of inorganic N-compounds were determined in the gaseous phase, size-segregated aerosol (coarse, medium, and fine), and rainwater samples. Dissolved organic nitrogen (DON) was quantified in rainwater. The daily variations in N-fluxes of compounds were evaluated with air-mass backward trajectories, classified into the main air-masses arriving at the sampling site (i.e., continental, North Sea, and Atlantic/UK/Channel). The three, non-episodic campaigns showed broadly consistent fluxes, but during the late summer campaign exceptionally high episodic N-deposition was observed. The average dry and wet fluxes for non-episodic campaigns amounted to 2.6 and 4.0 mg N m−2 d−1, respectively, whereas during the episodic late summer period these fluxes were as high as 5.2 and 6.2 mg N m−2 d−1, respectively. Non-episodic seasons/campaigns experienced average aerosol fluxes of 0.91.4 mg N m−2 d−1. Generally, the contribution of aerosol NH4+ was more significant in the medium and fine particulate fractions than that of aerosol NO3−, whereas the latter contributed more in the coarse fraction, especially in continental air-masses. During the dry mid-summer campaign, the DON contributed considerably (15%) to the total N-budget. Exceptionally high episodic aerosol-N inputs have been observed for the late summer campaign, with especially high deposition rates of 3.6 and 2.9 mg N m−2 d−1 for Atlantic/UK/Channel and North Sea-continental (mixed) air-masses, respectively. During this pollution episode, the flux of NH4+ was dominating in each aerosol fraction/air-mass, except for coarse continental aerosols. High deposition of gaseous-N was also observed in this campaign with an average total N-flux of 22.5-times higher than in other campaigns. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000268609000015 |
Publication Date |
2009-04-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1352-2310 |
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:77255 |
Serial |
7527 |
Permanent link to this record |
|
|
|
Author |
Nguyen, H.L.; Braun, M.; Szaloki, I.; Baeyens, W.; Van Grieken, R.; Leermakers, M. |
Title |
Tracing the metal pollution history of the Tisza River through the analysis of a sediment depth profile |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Water, air and soil pollution |
Abbreviated Journal |
|
Volume |
200 |
Issue |
|
Pages |
119-132 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The vertical profiles of 20 major and trace metals were investigated along a 180-cm-long sediment core, which was sampled at Kiss-Janosne-Holt Tisza, an oxbow lake located in the upper part of the Tisza River in Hungary. The vertical profiles showed sharp peaks at different depths, reflecting historical pollution events and unusual changes of river water characteristics. Five different groups of metals, containing metals which were strongly correlated and showing a similar behaviour, could be distinguished by factor analysis. Six areas, with variable degrees and types of contamination, were classified in the sediment core with cluster analysis. The most polluted sections were found in the upper 50-cm part (significantly contaminated by Cu, Zn, Pb, Cd and Hg) and the deeper 100120-cm part (characterised by high concentrations of metals associated with mining activities, such as Fe and Mn, as well as Cu, Zn and Pb). In recent years, important pollution events, such as the one which took place in March of 2000, were the reason for pollution of the upper sediment layers, whereas mining activities during the last century were responsible for the pollution of the deeper core sections. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000266487700012 |
Publication Date |
2008-10-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0049-6979; 1573-2932 |
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:77257 |
Serial |
8695 |
Permanent link to this record |
|
|
|
Author |
Idrissi, H.; Ryelandt, L.; Veron, M.; Schryvers, D.; Jacques, P.J. |
Title |
Is there a relationship between the stacking fault character and the activated mode of plasticity of FeMn-based austenitic steels? |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
Volume |
60 |
Issue |
11 |
Pages |
941-944 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
By changing the testing temperature, an austenitic FeMnAlSi alloy presents either å-martensite transformation or mechanical twinning during straining. In order to understand the nucleation and growth mechanisms involved in both phenomena, defects and particularly stacking faults, were characterized by transmission electron microscopy. It is observed that the character of the stacking faults also changes (from extrinsic to intrinsic) together with the temperature and the activated mode of plasticity. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000265359900005 |
Publication Date |
2009-02-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.747 |
Times cited |
84 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: 3.747; 2009 IF: 2.949 |
Call Number |
UA @ lucian @ c:irua:77276 |
Serial |
1751 |
Permanent link to this record |
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|
|
Author |
Müller, K.; Schowalter, M.; Jansen, J.; Tsuda, K.; Titantah, J.; Lamoen, D.; Rosenauer, A. |
Title |
Refinement of the 200 structure factor for GaAs using parallel and convergent beam electron nanodiffraction data |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
109 |
Issue |
7 |
Pages |
802-814 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We present a new method to measure structure factors from electron spot diffraction patterns recorded under almost parallel illumination in transmission electron microscopes. Bloch wave refinement routines have been developed to refine the crystal thickness, its orientation and structure factors by comparison of experimentally recorded and calculated intensities. Our method requires a modicum of computational effort, making it suitable for contemporary personal computers. Frozen lattice and Bloch wave simulations of GaAs diffraction patterns are used to derive optimised experimental conditions. Systematic errors are estimated from the application of the method to simulated diffraction patterns and rules for the recognition of physically reasonable initial refinement conditions are derived. The method is applied to the measurement of the 200 structure factor for GaAs. We found that the influence of inelastically scattered electrons is negligible. Additionally, we measured the 200 structure factor from zero loss filtered two-dimensional convergent beam electron diffraction patterns. The precision of both methods is found to be comparable and the results agree well with each other. A deviation of more than 20% from isolated atom scattering data is observed, whereas close agreement is found with structure factors obtained from density functional theory [A. Rosenauer, M. Schowalter, F. Glas, D. Lamoen, Phys. Rev. B 72 (2005), 085326-1], which account for the redistribution of electrons due to chemical bonding via modified atomic scattering amplitudes. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000266787900005 |
Publication Date |
2009-03-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
8 |
Open Access |
|
Notes |
Fwo; G.0425.05; Esteem; Ant 200611271505 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
Call Number |
UA @ lucian @ c:irua:77361 |
Serial |
2856 |
Permanent link to this record |
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|
|
Author |
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 |
|
Corporate Author |
|
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 |
Eckert, M.; Neyts, E.; Bogaerts, A. |
Title |
Modeling adatom surface processes during crystal growth: a new implementation of the Metropolis Monte Carlo algorithm |
Type |
A1 Journal article |
Year |
2009 |
Publication |
CrystEngComm |
Abbreviated Journal |
Crystengcomm |
Volume |
11 |
Issue |
8 |
Pages |
1597-1608 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, a new implementation of the Metropolis Monte Carlo (MMC) algorithm is presented. When combining the MMC model with a molecular dynamics (MD) code, crystal growth by plasma-enhanced chemical vapor deposition can be simulated. As the MD part simulates impacts of growth species onto the surface on a time scale of picoseconds, the MMC algorithm simulates the slower adatom surface processes. The implementation includes a criterion for the selection of atoms that are allowed to be displaced during the simulation, and a criterion of after how many MMC cycles the simulation is stopped. We performed combined MD-MMC simulations for hydrocarbon species that are important for the growth of ultrananocrystalline diamond (UNCD) films at partially hydrogenated diamond surfaces, since this implementation is part of a study of the growth mechanisms of (ultra)nanocrystalline diamond films. Exemplary for adatom arrangements during the growth of UNCD, the adatom surface behavior of C and C2H2 at diamond (111)1 × 1, C and C4H2 at diamond (111)1 × 1 and C3 at diamond (100)2 × 1 has been investigated. For all cases, the diamond crystal structure is pursued under the influence of MMC simulation. Additional longer time-scale MD simulations put forward very similar structures, verifying the MMC algorithm. Nevertheless, the MMC simulation time is typically one order of magnitude shorter than the MD simulation time. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000268184300021 |
Publication Date |
2009-04-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1466-8033; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.474 |
Times cited |
15 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.474; 2009 IF: 4.183 |
Call Number |
UA @ lucian @ c:irua:77374 |
Serial |
2106 |
Permanent link to this record |
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|
|
Author |
Matulis, A.; Peeters, F.M. |
Title |
Analogy between one-dimensional chain models and graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
American journal of physics |
Abbreviated Journal |
Am J Phys |
Volume |
77 |
Issue |
7 |
Pages |
595-601 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electron and hole spectrum in single and bilayer graphene is derived from known one-dimensional models, and the relation between the spectrum and symmetry of the lattice is shown. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000266976000003 |
Publication Date |
2009-06-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0002-9505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.069 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.069; 2009 IF: 0.779 |
Call Number |
UA @ lucian @ c:irua:77381 |
Serial |
97 |
Permanent link to this record |