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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 (down) UA @ lucian @ c:irua:77024 Serial 1123
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Author Moshnyaga, V.; Gehrke, K.; Sudheendra, L.; Belenchuk, A.; Raabe, S.; Shapoval, O.; Verbeeck, J.; Van Tendeloo, G.; Samwer, K.
Title Electrical nonlinearity in colossal magnetoresistance manganite films: relevance of correlated polarons Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue 13 Pages 134413,1-134413,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The metal-insulator (MI) transition in epitaxial thin films of La0.75Ca0.25MnO3 (LCMO) is accompanied by the appearance of an intrinsic electrical nonlinearity. The latter, probed by electrical third harmonic voltage, U3, or resistance, R3=dU3/dJ, is drastically enhanced in the vicinity of the MI transition, TMI=267 K. Applied magnetic field, B=5 T, suppresses the nonlinearity, resulting in a huge nonlinear CMR3(TMI)~105%. R3 shows a peculiar low-frequency (1 kHz) dependence, R3~(-0)n, with exponent, n, changing across the MI transition from n~1,52 for TTMI to n=1 (T<TMI). The observed electrical nonlinearity in LCMO reflects the behavior of correlated polarons, the number of which dramatically enhances in the vicinity of TMI. We argued that correlated polarons, considered as electric-elastic quadrupoles, provide a nonlinear (quadratic) coupling to the electric field, yielding a third harmonic electric nonlinearity in LCMO. The reference film of La0.7Sr0.3MnO3 (LSMO), a prototypic double exchange system with second-order phase transition, is characterized as a linear metallic material in the whole range of temperatures (T=10400 K), magnetic fields (B=05 T), and frequencies (=11000 Hz).
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000265942800074 Publication Date 2009-04-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 28 Open Access
Notes Esteem 026019 Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number (down) UA @ lucian @ c:irua:77022UA @ admin @ c:irua:77022 Serial 893
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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 (down) UA @ lucian @ c:irua:77021 Serial 3308
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Author 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
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 (down) UA @ lucian @ c:irua:76935 Serial 2492
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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
Corporate Author 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 (down) UA @ lucian @ c:irua:76874 Serial 865
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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
Corporate Author Thesis
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 (down) UA @ lucian @ c:irua:76844 Serial 2810
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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
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 (down) UA @ lucian @ c:irua:76833 Serial 461
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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
Corporate Author Thesis
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 (down) UA @ lucian @ c:irua:76671 Serial 1804
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Author Major, L.; Tirry, W.; Van Tendeloo, G.
Title Microstructure and defect characterization at interfaces in TiN/CrN multilayer coatings Type A1 Journal article
Year 2008 Publication Surface and coatings technology Abbreviated Journal Surf Coat Tech
Volume 202 Issue 24 Pages 6075-6080
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Microstructures of TiN/CrN multilayer coatings deposited on austenite steel (Cr Ni 18 8) by pulsed laser deposition (PLD) are characterized using transmission electron microscopy while their mechanical properties were assessed in a ball-on-disk test. All coatings have the same total thickness of about 1 ìm. The individual layers show a highly defective columnar structure, which is characterized by conventional electron microscopy (TEM) as well as by high resolution TEM. These techniques, combined with measurements of the local chemical composition through EDS prove that PLD allows to produce fully separated CrN and TiN layers. The friction, and consequently the wear, are lowered by increasing the total number of layers in the coating.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000260267100042 Publication Date 2008-07-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0257-8972; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.589 Times cited 23 Open Access
Notes Approved Most recent IF: 2.589; 2008 IF: 1.860
Call Number (down) UA @ lucian @ c:irua:76614 Serial 2049
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Author Turner, S.; Lebedev, O.I.; Schroeder, F.; Fischer, R.A.; Van Tendeloo, G.
Title Direct imaging of loaded metal-organic framework materials (metal@MOF-5) Type A1 Journal article
Year 2008 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 20 Issue 17 Pages 5622-5627
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We illustrate the potential of advanced transmission electron microscopy for the characterization of a new class of soft porous materials: metal@Zn4O(bdc)3 (metal@MOF-5; bdc = 1,4-benzenedicarboxylate). By combining several electron microscopy techniques (transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and electron tomography) and by carefully reducing the electron dose to avoid beam damage, it is possible to simultaneously characterize the MOF-5 framework material and the loaded metal nanoparticles. We also demonstrate that electron tomography can be used to accurately determine the position and distribution of the particles within the MOF-5 framework. To demonstrate the implementation of these microscopy techniques and what kind of results can be expected, measurements on gas-phase-loaded metal−organic framework materials Ru@MOF-5 and Pd@MOF-5 are presented.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000258941400021 Publication Date 2008-08-07
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 112 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2008 IF: 5.046
Call Number (down) UA @ lucian @ c:irua:76595 Serial 714
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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 (down) UA @ lucian @ c:irua:76592 Serial 1940
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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
Corporate Author 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 (down) UA @ lucian @ c:irua:76553 Serial 1837
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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 (down) UA @ lucian @ c:irua:76552 Serial 851
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Author Michel, K.H.; Verberck, B.
Title Theory of the evolution of phonon spectra and elastic constants from graphene to graphite Type A1 Journal article
Year 2008 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 78 Issue 8 Pages 085424,1-085424,17
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a unified theory of the phonon dispersions and elastic properties of graphene, graphite, and graphene multilayer systems. Starting from a fifth-nearest-neighbor force-constant model derived from full in-plane phonon dispersions of graphite [Mohr et al., Phys. Rev. B 76, 035439 (2007)], we use Born's long-wave method to calculate the tension and bending coefficients of graphene. Extending the model by interplanar interactions, we study the phonon dispersions and the elastic constants of graphite, and the phonon spectra of graphene multilayers. We find that the inner displacement terms due to sublattice shifts between inequivalent C atoms are quantitatively important in determining the elastomechanical properties of graphene and of graphite. The overall agreement between theory and experiment is very satisfactory. We investigate the evolution from graphene to graphite by studying the increase in the rigid plane optical mode as a function of the number of layers N. At N=10 the graphite value B2g1127 cm−1 is attained within a few percent.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000259406900106 Publication Date 2008-08-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 72 Open Access
Notes Approved Most recent IF: 3.836; 2008 IF: 3.322
Call Number (down) UA @ lucian @ c:irua:76527 Serial 3622
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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
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 (down) UA @ lucian @ c:irua:76526 Serial 3356
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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
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 (down) UA @ lucian @ c:irua:76525 Serial 1895
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Author Montoya, E.; Bals, S.; Van Tendeloo, G.
Title Redeposition and differential sputtering of La in transmission electron microscopy samples of LaAIO3/SrTiO3 multilayers prepared by focused ion beam Type A1 Journal article
Year 2008 Publication Journal of microscopy Abbreviated Journal J Microsc-Oxford
Volume 231 Issue 3 Pages 359-363
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000259611000001 Publication Date 2008-08-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2720;1365-2818; ISBN Additional Links UA library record; WoS full record
Impact Factor 1.692 Times cited Open Access
Notes The authors are grateful to M. Huijben and G. Rijnders of the MESA+ group at the University of Twente (NI) for the growth of the multilayers. This work has been performed under the Interuniversity Attraction Poles programme – Belgian State Belgian Science Policy. The authors acknowledge financial support from the European Union under the framework 6 program under a contract for an Integrated Infrastructure initiative. Part of this work was performed with financial support from the European Union under the framework 6 programme, under a contract for an Integrated Infrastructure Initiative (Reference No. 02601.9 ESTEEM). Approved Most recent IF: 1.692; 2008 IF: 1.409
Call Number (down) UA @ lucian @ c:irua:76522 Serial 2849
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Author Ghica, C.; Nistor, L.; Van Tendeloo, G.
Title Revealing nanoscale structural TEM/HRTEM: application on ferroelectric ordering by PMN-PT relaxor ferroelectric Type A1 Journal article
Year 2008 Publication Journal of optoelectronics and advanced materials Abbreviated Journal J Optoelectron Adv M
Volume 10 Issue 9 Pages 2328-2333
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Nano-scale ordering may be revealed in transmission electron microscopy (TEM) by at least three techniques that will be presented in this work: selected area electron diffraction, conventional TEM and high-resolution TEM. Digital image processing is used to extract additional information from the high-resolution micrographs. The described methods are illustrated in a microstructural and compositional study of a 90%Pb(Mg1/3Nb2/3)O-3-10%PbTiO2 ceramic sample. High-resolution images reveal the presence of ordered compositional nano-domains, observable in two specific crystallographic orientations. Antiphase boundaries lying in the (111) planes separate them, while (100) and (111) facets separate the ordered domains from the disordered matrix.
Address
Corporate Author Thesis
Publisher Place of Publication Bucharest Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1454-4164 ISBN Additional Links UA library record; WoS full record;
Impact Factor 0.449 Times cited Open Access
Notes Approved Most recent IF: 0.449; 2008 IF: 0.577
Call Number (down) UA @ lucian @ c:irua:76520 Serial 2901
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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
Corporate Author 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 (down) UA @ lucian @ c:irua:76519 Serial 2348
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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
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 (down) UA @ lucian @ c:irua:76496 Serial 719
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Author Neyts, E.C.; Bogaerts, A.
Title Numerical study of the size-dependent melting mechanisms of nickel nanoclusters Type A1 Journal article
Year 2009 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 113 Issue 7 Pages 2771-2776
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Molecular dynamics simulations were used to investigate the size-dependent melting mechanism of nickel nanoclusters of various sizes. The melting process was monitored by the caloric curve, the overall cluster Lindemann index, and the atomic Lindemann index. Size-dependent melting temperatures were determined, and the correct linear dependence on inverse diameter was recovered. We found that the melting mechanism gradually changes from dynamic coexistence melting to surface melting with increasing cluster size. These findings are of importance in better understanding carbon nanotube growth by catalytic chemical vapor deposition as the phase state of the catalyst nanoparticle codetermines the growth mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited Open Access
Notes Approved Most recent IF: 4.536; 2009 IF: 4.224
Call Number (down) UA @ lucian @ c:irua:76495 Serial 2410
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Author Verbeeck, J.; Hébert; Rubino, S.; Novák, P.; Rusz, J.; Houdellier, F.; Gatel, C.; Schattschneider, P.
Title Optimal aperture sizes and positions for EMCD experiments Type A1 Journal article
Year 2008 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 108 Issue 9 Pages 865-872
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The signal-to-noise ratio (SNR) in energy-loss magnetic chiral dichroism (EMCD)the equivalent of X-ray magnetic circular dichroism (XMCD) in the electron microscopeis optimized with respect to the detector shape, size and position. We show that an important increase in SNR over previous experiments can be obtained when taking much larger detector sizes. We determine the ideal shape of the detector but also show that round apertures are a good compromise if placed in their optimal position. We develop the theory for a simple analytical description of the EMCD experiment and then apply it to dynamical multibeam Bloch wave calculations and to an experimental data set. In all cases it is shown that a significant and welcome improvement of the SNR is possible.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000258747600009 Publication Date 2008-03-07
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 27 Open Access
Notes This work was supported by the European Commission under contract no. 508971 CHIRALTEM. J.V. and F.H. thank the financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. Thanks to J.P. Morniroli for making the Fe sample available. Approved Most recent IF: 2.843; 2008 IF: 2.629
Call Number (down) UA @ lucian @ c:irua:76492UA @ admin @ c:irua:76492 Serial 2480
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Author Bittencourt, C.; Hecq, M.; Felten, A.; Pireaux, J.J.; Ghijsen, J.; Felicissimo, M.P.; Rudolf, P.; Drube, W.; Ke, X.; Van Tendeloo, G.
Title Platinumcarbon nanotube interaction Type A1 Journal article
Year 2008 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 462 Issue 4/6 Pages 260-264
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The interaction between evaporated Pt and pristine or oxygen-plasma-treated multiwall carbon nanotubes (CNTs) is investigated. Pt is found to nucleate at defect sites, whether initially present or introduced by oxygen plasma treatment. The plasma treatment induces a uniform dispersion of Pt nanoparticles at the CNT surface. The absence of additional features in the C 1s core level spectrum indicates that no mixed PtC phase is formed. The formation of COPt bonds at the cluster-CNT interface is suggested to reduce the electronic interaction between Pt nanoparticles and the CNT surface.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000258830900025 Publication Date 2008-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 62 Open Access
Notes Pai Approved Most recent IF: 1.815; 2008 IF: 2.169
Call Number (down) UA @ lucian @ c:irua:76489 Serial 2652
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Author Zhao, H.J.; Misko, V.R.; Peeters, F.M.; Dubonos, G.; Oboznov, V.; Grigorieva, I.V.
Title Vortex configurations in mesoscopic superconducting triangles: finite-size and shape effects Type A1 Journal article
Year 2008 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett
Volume 83 Issue 1 Pages 17008,1-17008,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Triangular-shaped mesoscopic superconductors are consistent with the symmetry of the Abrikosov vortex lattice resulting in a high stability of vortex patterns for commensurate vorticities. However, for non-commensurate vorticities, vortex configurations in triangles are not compatible with the sample shape. Here we present the first direct observation of vortex configurations in ìm-sized niobium triangles using the Bitter decoration technique, and we analyze the vortex states in triangles by analytically solving the London equations and performing molecular-dynamics simulations. We found that filling rules with increasing vorticity can be formulated for triangles in a similar way as for mesoscopic disks where vortices form shells.
Address
Corporate Author Thesis
Publisher Place of Publication Paris Editor
Language Wos 000259020300030 Publication Date 2008-06-17
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 29 Open Access
Notes Approved Most recent IF: 1.957; 2008 IF: 2.203
Call Number (down) UA @ lucian @ c:irua:76488 Serial 3863
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Author Felten, A.; Ghijsen, J.; Pireaux, J.-J.; Whelan, C.M.; Liang, D.; Van Tendeloo, G.; Bittencourt, C.
Title Photoemission study of CF4 rf-plasma treated multi-wall carbon nanotubes Type A1 Journal article
Year 2008 Publication Carbon Abbreviated Journal Carbon
Volume 46 Issue 10 Pages 1271-1275
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Multi-wall carbon nanotubes (MWCNTs) were exposed to a CF4 rf-plasma. X-ray photoelectron spectroscopy analysis shows that the treatment effectively grafts fluorine atoms onto the MWCNTs. The fluorine atomic concentration and the nature of the CF bond (semi-ionic or covalent) can be tuned by varying the exposure time. Ultraviolet photoelectron spectroscopy analysis confirms that the valence electronic states are altered by the grafting of fluorine atoms. Characterization with high-resolution transmission electron microscopy reveals that while the plasma treatment does not induce significant etching impact on the CNT-surface, it does increase the number of active sites for gold cluster formation.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000258987500001 Publication Date 2008-05-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited 21 Open Access
Notes Approved Most recent IF: 6.337; 2008 IF: 4.373
Call Number (down) UA @ lucian @ c:irua:76481 Serial 2612
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Author 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.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000266639300002 Publication Date 2009-05-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 21 Open Access
Notes Approved Most recent IF: 2.588; 2009 IF: 2.083
Call Number (down) UA @ lucian @ c:irua:76458 Serial 2450
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Author de Backer, J.W.; Vos, W.G.; Burnell, P.; Verhulst, S.L.; Salmon, P.; de Clerck, N.; de Backer, W.
Title Study of the variability in upper and lower airway morphology in Sprague-Dawley rats using modern micro-CT scan-based segmentation techniques Type A1 Journal article
Year 2009 Publication The anatomical record: advances in integrative anatomy and evolutionary biology Abbreviated Journal Anat Rec
Volume 292 Issue 5 Pages 720-727
Keywords A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Animal models are being used extensively in pre-clinical and safety assessment studies to assess the effectiveness and safety of new chemical entities and delivery systems. Although never entirely replacing the need for animal testing, the use of computer simulations could eventually reduce the amount of animals needed for research purposes and refine the data acquired from the animal studies. Computational fluid dynamics is a powerful tool that makes it possible to simulate flow and particle behavior in animal or patient-specific respiratory models, for purposes of inhaled delivery. This tool requires an accurate representation of the respiratory system, respiration and dose delivery attributes. The aim of this study is to develop a representative airway model of the Sprague-Dawley rat using static and dynamic micro-CT scans. The entire respiratory tract was modeled, from the snout and nares down to the central airways at the point where no distinction could be made between intraluminal air and the surrounding tissue. For the selection of the representative model, variables such as upper airway movement, segmentation length, airway volume and size are taken into account. Dynamic scans of the nostril region were used to illustrate the characteristic morphology of this region in anaesthetized animals. It could be concluded from this study that it was possible to construct a highly detailed representative model of a Sprague-Dawley rat based on imaging modalities such as micro-CT scans
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000265766000010 Publication Date 2009-03-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-8486;1932-8494; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.431 Times cited 16 Open Access
Notes Approved Most recent IF: 1.431; 2009 IF: 1.490
Call Number (down) UA @ lucian @ c:irua:76455 Serial 3342
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Author Burriel, M.; Santiso, J.; Rossell, M.D.; Van Tendeloo, G.; Figueras, A.; Garcia, G.
Title Enhancing total conductivity of La2NiO4+\delta epitaxial thin films by reducing thickness Type A1 Journal article
Year 2008 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 112 Issue 29 Pages 10982-10987
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High quality epitaxial c axis oriented La2NiO4+ä thin films have been prepared by the pulsed injection metal organic chemical vapor deposition technique on different substrates. High-resolution electron microscopy/transmission electron microscopy has been used to confirm the high crystalline quality of the deposited films. The c-parameter evolution has been studied by XRD as a function of time and gas atmosphere. The high temperature transport properties along the basal a−b plane of epitaxial La2NiO4+ä films have been measured, and the total conductivity of the layers has been found to increase as the thickness is reduced. Layers of 50 nm and thinner have shown a maximum conductivity larger than that measured for single-crystals, in particular, the 33 nm thick films with a conductivity of 475 S/cm in oxygen correspond to the highest value measured to date for this material.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000257724100057 Publication Date 2008-06-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 35 Open Access
Notes Approved Most recent IF: 4.536; 2008 IF: 3.396
Call Number (down) UA @ lucian @ c:irua:76440 Serial 1067
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Author Neyts, E.C.; Bogaerts, A.
Title Formation of endohedral Ni@C60 and exohedral NiC60 metallofullerene complexes by simulated ion implantation Type A1 Journal article
Year 2009 Publication Carbon Abbreviated Journal Carbon
Volume 47 Issue 4 Pages 1028-1033
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The interaction of thermal and hyperthermal Ni ions with gas-phase C60 fullerene was investigated at two temperatures with classical molecular dynamics simulations using a recently developed interatomic many-body potential. The interaction between Ni and C60 is characterized in terms of the NiC60 binding sites, complex formation, and the collision and temperature induced deformation of the C60 cage structure. The simulations show how ion implantation theoretically allows the synthesis of both endohedral Ni@C60 and exohedral NiC60 metallofullerene complexes.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000264252900012 Publication Date 2008-12-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited 15 Open Access
Notes Approved Most recent IF: 6.337; 2009 IF: 4.504
Call Number (down) UA @ lucian @ c:irua:76434 Serial 1260
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Author Caignaert, V.; Abakumov, A.M.; Pelloquin, D.; Pralong, V.; Maignan, A.; Van Tendeloo, G.; Raveau, B.
Title A new mixed-valence ferrite with a cubic structure, YBaFe4O7: spin-glass-like behavior Type A1 Journal article
Year 2009 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 21 Issue 6 Pages 1116-1122
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new mixed-valence ferrite, YBaFe4O7, has been synthesized. Its unique cubic structure, with a = 8.9595(2) Å, is closely related to that of the hexagonal 114 oxides YBaCo4O7 and CaBaFe4O7. It consists of corner-sharing FeO4 tetrahedra, forming triangular and kagome layers parallel to (111)C. In fact, the YBaFe4O7 and CaBaFe4O7 structures can be described as two different ccc and chch close packings of [BaO3]∞ and [O4]∞ layers, respectively, whose tetrahedral cavities are occupied by Fe2+/Fe3+ cations. The local structure of YBaFe4O7 is characterized by a large amount of stacking faults originating from the presence of hexagonal layers in the ccc cubic close-packed YBaFe4O7 structure. In this way, they belong to the large family of spinels and hexagonal ferrites studied for their magnetic properties. Differently from all the ferrites and especially from CaBaFe4O7, which are ferrimagnetic, YBaFe4O7 is an insulating spin glass with Tg = 50 K.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000264310900019 Publication Date 2009-02-25
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 39 Open Access
Notes Esteem 026019 Approved Most recent IF: 9.466; 2009 IF: 5.368
Call Number (down) UA @ lucian @ c:irua:76432 Serial 2325
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