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Author Chaves, A.; Farias, G.A.; Peeters, F.M.; Szafran, B.
Title Wave packet dynamics in semiconductor quantum rings of finite width Type A1 Journal article
Year (down) 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 80 Issue 12 Pages 125331,1-125331,14
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The time evolution of a wave packet injected into a semiconductor quantum ring is investigated in order to obtain the transmission and reflection probabilities. Within the effective-mass approximation, the time-dependent Schrödinger equation is solved for a system with nonzero width of the ring and leads and finite potential-barrier heights, where we include smooth lead-ring connections. In the absence of a magnetic field, an analysis of the projection of the wave function over the different subband states shows that when the injected wave packet is within a single subband, the junction can scatter this wave packet into different subbands but remarkably at the second junction the wave packet is scattered back into the subband state of the incoming wave packet. If a magnetic field is applied perpendicularly to the ring plane, transmission and reflection probabilities exhibit Aharonov-Bohm (AB) oscillations and the outgoing electrons may end up in different subband states from those of the incoming electrons. Localized impurities, placed in the ring arms, influence the AB oscillation period and amplitude. For a single impurity or potential barrier of sufficiently strong strength, the period of the AB oscillations is halved while for two impurities localized in diametrically opposite points of the ring, the original AB period is recovered. A theoretical investigation of the confined states and time evolution of wave packets in T wires is also made, where a comparison between this system and the lead-ring junction is drawn.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000270383300098 Publication Date 2009-09-25
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 40 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:79231 Serial 3906
Permanent link to this record
 
 
Author Tkachenko, D.V.; Misko, V.R.; Peeters, F.M.
Title Dynamics of colloids in a narrow channel driven by a nonuniform force Type A1 Journal article
Year (down) 2009 Publication Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E
Volume 80 Issue 5 Pages 051401,1-051401,10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using Brownian dynamics simulations, we investigate the dynamics of colloids confined in two-dimensional narrow channels driven by a nonuniform force Fdr(y). We considered linear-gradient, parabolic, and deltalike driving-force profiles. This driving force induces melting of the colloidal solid (i.e., shear-induced melting), and the colloidal motion experiences a transition from elastic to plastic regime with increasing Fdr. For intermediate Fdr (i.e., in the transition region) the response of the system, i.e., the distribution of the velocities of the colloidal chains õi(y), in general does not coincide with the profile of the driving force Fdr(y), and depends on the magnitude of Fdr, the width of the channel, and the density of colloids. For example, we show that the onset of plasticity is first observed near the boundaries while the motion in the central region is elastic. This is explained by: (i) (in)commensurability between the chains due to the larger density of colloids near the boundaries, and (ii) the gradient in Fdr. Our study provides a deeper understanding of the dynamics of colloids in channels and could be accessed in experiments on colloids (or in dusty plasma) with, e.g., asymmetric channels or in the presence of a gradient potential field.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000272309500045 Publication Date 2009-11-10
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 14 Open Access
Notes Approved Most recent IF: 2.366; 2009 IF: 2.400
Call Number UA @ lucian @ c:irua:80313 Serial 774
Permanent link to this record
 
 
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 (down) 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 Doğan, F.; Covaci, L.; Kim, W.; Marsiglio, F.
Title Emerging nonequilibrium bound state in spin-current–local-spin scattering Type A1 Journal article
Year (down) 2009 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 80 Issue 10 Pages 104434
Keywords A1 Journal article
Abstract Magnetization reversal is a well-studied problem with obvious applicability in computer hard drives. One can accomplish a magnetization reversal in at least one of two ways: application of a magnetic field or through a spin current. The latter is more amenable to a fully quantum-mechanical analysis. We formulate and solve the problem whereby a spin current interacts with a ferromagnetic Heisenberg spin chain, to eventually reverse the magnetization of the chain. Spin flips are accomplished through both elastic and inelastic scattering. A consequence of the inelastic-scattering channel, when it is no longer energetically possible, is the occurrence of a nonequilibrium bound state, which is an emergent property of the coupled local plus itinerant spin system. For certain definite parameter values the itinerant spin lingers near the local spins for some time, before eventually leaking out as an outwardly diffusing state. This phenomenon results in spin-flip dynamics and filtering properties for this type of system.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000270383100077 Publication Date 2009-09-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links
Impact Factor 3.836 Times cited Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ Serial 4436
Permanent link to this record
 
 
Author Payette, C.; Yu, G.; Gupta, J.A.; Austing, D.G.; Nair, S.V.; Partoens, B.; Amaha, S.; Tarucha, S.
Title Coherent three-level mixing in an electronic quantum dot Type A1 Journal article
Year (down) 2009 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 102 Issue 2 Pages 026808,1-026808,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We observe magnetic-field-induced level mixing and quantum superposition phenomena between three approaching single-particle states in a quantum dot probed via the ground state of an adjacent quantum dot by single-electron resonant tunneling. The mixing is attributed to anisotropy and anharmonicity in realistic dot confining potentials. The pronounced anticrossing and transfer of strengths (both enhancement and suppression) between resonances can be understood with a simple coherent level mixing model. Superposition can lead to the formation of a dark state by complete cancellation of an otherwise strong resonance, an effect resembling coherent population trapping in a three-level-system of quantum and atom optics.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000262535900060 Publication Date 2009-01-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 26 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ c:irua:76019 Serial 382
Permanent link to this record
 
 
Author Berdiyorov, G.R.; Hernandez, A.D.; Peeters, F.M.
Title Confinement effects on intermediate-state flux patterns in mesoscopic type-I superconductors Type A1 Journal article
Year (down) 2009 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 103 Issue 26 Pages 267002,1-267002,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Intermediate-state flux structures in mesoscopic type-I superconductors are studied within the Ginzburg-Landau theory. In addition to well-established tubular and laminar structures, the strong confinement leads to the formation of (i) a phase of singly quantized vortices, which is typical for type-II superconductors and (ii) a ring of a normal domain at equilibrium. The stability region and the formation process of these intermediate-state structures are strongly influenced by the geometry of the sample.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000273232200042 Publication Date 2009-12-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 28 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ c:irua:80574 Serial 488
Permanent link to this record
 
 
Author Milošević, M.V.; Kanda, A.; Hatsumi, S.; Peeters, F.M.; Ootuka, Y.
Title Local current injection into mesoscopic superconductors for the manipulation of quantum states Type A1 Journal article
Year (down) 2009 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 103 Issue 21 Pages 217003-217003,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We perform strategic current injection in a small mesoscopic superconductor and control the (non)equilibrium quantum states in an applied homogeneous magnetic field. In doing so, we realize a current-driven splitting of multiquanta vortices, current-induced transitions between states with different angular momenta, and current-controlled switching between otherwise degenerate quantum states. These fundamental phenomena form the basis for the electronic and logic applications discussed, and are confirmed in both theoretical simulations and multiple-small-tunnel-junction transport measurements.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000272054300044 Publication Date 2009-12-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 48 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ c:irua:94498 Serial 1826
Permanent link to this record
 
 
Author Kalina, R.; Szafran, B.; Bednarek, S.; Peeters, F.M.
Title Magnetic-field asymmetry of electron wave packet transmission in bent channels capacitively coupled to a metal gate Type A1 Journal article
Year (down) 2009 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 102 Issue 6 Pages 066807,1-066807,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the electron wave packet moving through a bent channel. We demonstrate that the packet transmission probability becomes an asymmetric function of the magnetic field when the electron packet is capacitively coupled to a metal plate. The coupling occurs through a nonlinear potential which translates a different kinetics of the transport for opposite magnetic-field orientations into a different potential felt by the scattered electron.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000263389500056 Publication Date 2009-02-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 14 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ c:irua:76315 Serial 1867
Permanent link to this record
 
 
Author Lin, N.S.; Misko, V.R.; Peeters, F.M.
Title Unconventional vortex dynamics in mesoscopic superconducting corbino disks Type A1 Journal article
Year (down) 2009 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 102 Issue 19 Pages 197003,1-197003,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The discrete shell structure of vortex matter strongly influences the flux dynamics in mesoscopic superconducting Corbino disks. While the dynamical behavior is well understood in large and in very small disks, in the intermediate-size regime it occurs to be much more complex and unusual, due to (in)commensurability between the vortex shells. We demonstrate unconventional vortex dynamics (inversion of shell velocities with respect to the gradient driving force) and angular melting (propagating from the boundary where the shear stress is minimum, towards the center) in mesoscopic Corbino disks.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000266207700063 Publication Date 2009-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 18 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ c:irua:77396 Serial 3800
Permanent link to this record
 
 
Author Goodvin, G.L.; Covaci, L.; Berciu, M.
Title Holstein polarons near surfaces Type A1 Journal article
Year (down) 2009 Publication Physical Review Letters Abbreviated Journal Phys Rev Lett
Volume 103 Issue 17 Pages 176402
Keywords A1 Journal article
Abstract We study the effects of a nearby surface on the spectral weight of a Holstein polaron, using the inhomogeneous momentum average approximation which is accurate over the entire range of electron-phonon (e-ph) coupling strengths. The broken translational symmetry is taken into account exactly. We find that the e-ph coupling gives rise to a large additional surface potential, with strong retardation effects, which may bind surface states even when they are not normally expected. The surface, therefore, has a significant effect and bulk properties are recovered only very far away from it. These results demonstrate that interpretation in terms of bulk quantities of spectroscopic data sensitive only to a few surface layers is not always appropriate.
Address Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000271164500042 Publication Date 2009-10-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links
Impact Factor 8.462 Times cited 8 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ Serial 4435
Permanent link to this record
 
 
Author Covaci, L.; Berciu, M.
Title Polaron formation in the presence of Rashba spin-orbit coupling: implications for spintronics Type A1 Journal article
Year (down) 2009 Publication Physical Review Letters Abbreviated Journal Phys Rev Lett
Volume 102 Issue 18 Pages 186403
Keywords A1 Journal article
Abstract We study the effects of the Rashba spin-orbit coupling on polaron formation, using a suitable generalization of the momentum average approximation. While previous work on a parabolic band model found that spin-orbit coupling increases the effective mass, we show that the opposite holds for a tight-binding model, unless both the spin-orbit and the electron-phonon couplings are weak. It is thus possible to lower the effective mass of the polaron by increasing the spin-orbit coupling. We also show that when the spin-orbit coupling is large as compared to the phonon energy, the polaron retains only one of the spin-polarized bands in its coherent spectrum. This has major implications for the propagation of spin-polarized currents in such materials, and thus for spintronic applications.
Address Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z1
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000265948600049 Publication Date 2009-05-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links
Impact Factor 8.462 Times cited 25 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ Serial 4434
Permanent link to this record
 
 
Author Salje, E.K.H.; Zhang, H.; Idrissi, H.; Schryvers, D.; Carpenter, M.A.; Moya, X.; Planes, A.
Title Mechanical resonance of the austenite/martensite interface and the pinning of the martensitic microstructures by dislocations in Cu74.08Al23.13Be2.79 Type A1 Journal article
Year (down) 2009 Publication Physical review: B: condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 80 Issue 13 Pages 134114,1-1134114,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A single crystal of Cu74.08Al23.13Be2.79 undergoes a martensitic phase transition at 246 and 232 K under heating and cooling, respectively. The phase fronts between the austenite and martensite regions of the sample are weakly mobile with a power-law resonance under external stress fields. Surprisingly, the martensite phase is elastically much harder than the austenite phase showing that interfaces between various crystallographic variants are strongly pinned and cannot be moved by external stress while the phase boundary between the austenite and martensite regions in the sample remains mobile. This unusual behavior was studied by dynamical mechanical analysis (DMA) and resonant ultrasound spectroscopy. The remnant strain, storage modulus, and internal friction were recorded simultaneously for different applied forces in DMA. With increasing forces, the remnant strain increases monotonously while the internal friction peak height shows a minimum at 300 mN. Transmission electron microscopy shows that the pinning is generated by dislocations which are inherited from the austenite phase.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000271351300033 Publication Date 2009-10-22
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 38 Open Access
Notes Multimat Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:78542 Serial 1975
Permanent link to this record
 
 
Author Matthai, C.C.; March, N.H.; Lamoen, D.
Title Supercooled molecular liquids and the glassy phases of chemically bonded N, P, As, Si and Ge Type A1 Journal article
Year (down) 2009 Publication Physics and chemistry of liquids Abbreviated Journal Phys Chem Liq
Volume 47 Issue 6 Pages 607-613
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Glassy phases which have insulating character exist for a variety of monatomic species. By contrast, until recently, it has been possible to make bulk metallic glasses (BMG) by vitrification only for multicomponent systems. After a relatively brief summary on supercooling of a few molecular liquids, we review some of the recently reported results on molecular assemblies of the series N, P, As and amorphous Si and Ge. Based on these results, we suggest that the transition metals with their directional bonding might be suitable candidates for the production of BMG by vitrification.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000273047400003 Publication Date 2009-11-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9104;1029-0451; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.145 Times cited 1 Open Access
Notes BoF Approved Most recent IF: 1.145; 2009 IF: 0.580
Call Number UA @ lucian @ c:irua:80653 Serial 3376
Permanent link to this record
 
 
Author Lamoen, D.; March, N.H.
Title Orientational disorder in some molecular solids in relation to the boson peak in glasses Type A1 Journal article
Year (down) 2009 Publication Physics letters : A Abbreviated Journal Phys Lett A
Volume 373 Issue 7 Pages 799-800
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Orientational disorder in some molecular solids is discussed in relation to the emphasis placed on transverse vibrational modes in glasses as the origin of the observed boson peak in two very recent contributions in Nature Materials. In particular, facts are here presented for (i) CH4, (ii) C60 and (iii) ethanol in their solid phases for (a) specific heat and (b) neutron scattering. The results for ethanol in particular do not fit in with the interpretation of the boson peak in terms of transverse acoustic phonons in disordered systems. Glasses will therefore have to be separated into at least two classes where the physical interpretation of the boson peak is concerned.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000263515500020 Publication Date 2009-01-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0375-9601; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.772 Times cited 3 Open Access
Notes Bof Approved Most recent IF: 1.772; 2009 IF: 2.009
Call Number UA @ lucian @ c:irua:72917 Serial 2516
Permanent link to this record
 
 
Author Neyts, E.; Eckert, M.; Mao, M.; Bogaerts, A.
Title Numerical simulation of hydrocarbon plasmas for nanoparticle formation and the growth of nanostructured thin films Type A1 Journal article
Year (down) 2009 Publication Plasma physics and controlled fusion Abbreviated Journal Plasma Phys Contr F
Volume 51 Issue Pages 124034,1-124034,8
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract This paper outlines two different numerical simulation approaches, carried out by our group, used for describing hydrocarbon plasmas in their applications for either nanoparticle formation in the plasma or the growth of nanostructured thin films, such as nanocrystalline diamond (NCD). A plasma model based on the fluid approach is utilized to study the initial mechanisms giving rise to nanoparticle formation in an acetylene plasma. The growth of NCD is investigated by molecular dynamics simulations, describing the interaction of the hydrocarbon species with a substrate.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000271940800045 Publication Date 2009-11-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0741-3335;1361-6587; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.392 Times cited 2 Open Access
Notes Approved Most recent IF: 2.392; 2009 IF: 2.409
Call Number UA @ lucian @ c:irua:79132 Serial 2405
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 (down) 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 UA @ lucian @ c:irua:76833 Serial 461
Permanent link to this record
 
 
Author Saraiva, M.; Chen, H.; Leroy, W.P.; Mahieu, S.; Jehanathan, N.; Lebedev, O.; Georgieva, V.; Persoons, R.; Depla, D.
Title Influence of Al content on the properties of MgO grown by reactive magnetron sputtering Type A1 Journal article
Year (down) 2009 Publication Plasma processes and polymers Abbreviated Journal Plasma Process Polym
Volume 6 Issue S:1 Pages S751-S754
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In the present work, reactive magnetron sputtering in DC mode was used to grow complex oxide thin films, starting from two separate pure metal targets. A series of coatings was produced with a stoichiometry of the film ranging from MgO, over MgxAlyOz to Al2O3. The surface energy, crystallinity, hardness, refractive index, and surface roughness were investigated. A relationship between all properties studied and the Mg content of the samples was found. A critical compositional region for the Mg-Al-O system where all properties exhibit a change was noticed.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000272302900144 Publication Date 2009-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1612-8850; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.846 Times cited 13 Open Access
Notes Iwt Approved Most recent IF: 2.846; 2009 IF: 4.037
Call Number UA @ lucian @ c:irua:79363 Serial 1613
Permanent link to this record
 
 
Author Bultinck, E.; Mahieu, S.; Depla, D.; Bogaerts, A.
Title Particle-in-cell/Monte Carlo collisions model for the reactive sputter deposition of nitride layers Type A1 Journal article
Year (down) 2009 Publication Plasma processes and polymers Abbreviated Journal Plasma Process Polym
Volume 6 Issue S:1 Pages S784-S788
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A 2d3v Particle-in-cell/Monte Carlo collisions (PIC/MCC) model was constructed for an Ar/N2 reactive gas mixture in a magnetron discharge. A titanium target was used, in order to study the sputter deposition of a TiNx thin film. Cathode currents and voltages were calculated self-consistently and compared with experiments. Also, ion fluxes to the cathode were calculated, which cause sputtering of the target. The sputtered atom fluxes from the target, and to the substrate were calculated, in order to visualize the deposition of the TiNx film.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000272302900149 Publication Date 2009-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1612-8850; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.846 Times cited 2 Open Access
Notes Approved Most recent IF: 2.846; 2009 IF: 4.037
Call Number UA @ lucian @ c:irua:79364 Serial 2558
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 (down) 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
 
 
Author Delville, R.; Schryvers, D.; Zhang, Z.; James, R.D.
Title Transmission electron microscopy investigation of microstructures in low-hysteresis alloys with special lattice parameters Type A1 Journal article
Year (down) 2009 Publication Scripta materialia Abbreviated Journal Scripta Mater
Volume 60 Issue 5 Pages 293-296
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A sharp drop in hysteresis is observed for shape memory alloys satisfying the compatibility condition between austenite and martensite, i.e. ë2 = 1, where ë2 is the middle eigenvalue of the transformation strain matrix. The present work investigates the evolution of microstructure by transmission electron microscopy as the composition of the Ti50Ni50−xPdx system is systemically tuned to achieve the condition ë2 = 1. Changes in morphology, twinning density and twinning modes are reported along with twinless martensite and exact austenitemartensite interfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000262553300007 Publication Date 2008-11-08
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 56 Open Access
Notes Multimat Approved Most recent IF: 3.747; 2009 IF: 2.949
Call Number UA @ lucian @ c:irua:76017 Serial 3710
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Author Dominiczak, M.; Ruyter, A.; Limelette, P.; Monot-Laffez, I.; Giovannelli, F.; Rossell, M.D.; Van Tendeloo, G.
Title Effects of nanocracks on the magnetic and electrical properties of La0.8Sr0.2MnO3 single crystals Type A1 Journal article
Year (down) 2009 Publication Solid state communications Abbreviated Journal Solid State Commun
Volume 149 Issue 37/38 Pages 1543-1548
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An investigation of the physical properties of La0.8Sr0.2MnO3 single crystals grown by the molten zone technique is realized close to the metal-to-insulator transition temperature (TMI). In this paper, we review the effect of the structural defects through magnetotransport and local magnetic microstructures. From electron microscopy observations, some nanocrack defects (i.e. defects at a nanometer scale) were found, essentially in the center part of the single crystals. At room temperature, magnetic force microscopy measurements have shown that the absence of defects allowed a magnetic ordering of the domains at the crystal edge, which is the best-crystallized region. In addition, the magnetization loops have permitted us to verify that the crystal was ferromagnetically weaker in the center. On analyzing the electrical resistivity data, we observed in the linear current regime a sensitive variation of the resistivity due to defects, by comparing the center and the edge of the material at TMI. Additionally, at strong current, non-linearity phenomena have been supposed to be related to local heating. Finally, we discuss the structural disorder effect on the relaxation of the ferromagnetic domains.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000269679500012 Publication Date 2009-06-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.554 Times cited 3 Open Access
Notes Approved Most recent IF: 1.554; 2009 IF: 1.837
Call Number UA @ lucian @ c:irua:78289 Serial 868
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Author Papp, G.; Peeters, F.M.
Title Magneto-ballistic transport through micro-structured junctions on a curved two-dimensional electron gas Type A1 Journal article
Year (down) 2009 Publication Solid state communications Abbreviated Journal Solid State Commun
Volume 149 Issue 19/20 Pages 778-780
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate theoretically the ballistic transport in a two-dimensional electron gas, which is rolled up as a tube and is micro-structured into a Hall bar. A uniform magnetic field applied to such a curved surface results in a non-uniform perpendicular magnetic field. The bend resistances become asymmetric with respect to the orientation of the magnetic field due to the varying magnetic field along the junction. The resistance asymmetry is strongly affected by corrugation due to the varying mobility along different crystallographic directions. We compare our results with a recent transport measurement.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000266149900011 Publication Date 2009-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.554 Times cited 1 Open Access
Notes Approved Most recent IF: 1.554; 2009 IF: 1.837
Call Number UA @ lucian @ c:irua:77580 Serial 1897
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Author Baltas, H.; Čevik, U.
Title Variation of K X-ray fluorescence cross-sections of Cu, Y and Ba in YBa2Cu3O7-\delta superconductor Type A1 Journal article
Year (down) 2009 Publication Solid state communications Abbreviated Journal
Volume 149 Issue 5/6 Pages 231-235
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract K X-ray fluorescence cross-sections of Cu, Y and Ba elements were measured in CuO, Y(2)O(3), BaCO(3) Compounds and YBa(2)Cu(3)O(7-delta) superconductor samples (nonreacted agent, calcined and sintered states). A superconductor sample of YBa(2)Cu(3)O(7-delta) was prepared by using a solid-state reaction technique. The samples were excited by gamma rays of energy 59.5 keV from a (241)Am radioisotope source. The Cu, Y and Ba K X-ray intensities counted with a Si(Li) detector were measured in different solid-state conditions. The obtained values of K X-ray fluorescence cross-section were compared with the theoretical values of pure Cu, Y and Ba elements. We found that the K X-ray fluorescence cross-section of Cu, Y and Ba in YBa(2)Cu(3)O(7-delta) sample is changed in different solid-state conditions, depending on the mixture (nonreacted agent), calcined and sintered states. (c) 2008 Elsevier Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000262795900013 Publication Date 2008-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1098 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:94568 Serial 8735
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Author Lepoittevin, C.; Malo, S.; Van Tendeloo, G.; Hervieu, M.
Title Synthesis and structural mechanisms of the 2201-type ferrites and polytypes: Fe2(Sr2-xAx)FeO6.5-\delta/2 (A = Ba, La, Tl, Pb and Bi) Type A1 Journal article
Year (down) 2009 Publication Solid state sciences Abbreviated Journal Solid State Sci
Volume 11 Issue 3 Pages 595-607
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The Fe2(Sr2 − xAx)FeO6.5 − ä/2 systems have been investigated, by doping the iron rich 2201-type parent structure with Ba2+, La3+ and 5d10 post-transition cations. The syntheses have been carried out up to the limit of the 2201-type solid solutions, in order to test the role of the double iron layer Fe2O2.5 − ä/2. The localisation of the charge carriers in these compounds is consistent with their strong antiferro-magnetism. The investigation was then carried out in the transition part of the diagram up to the formation of stable phases. The study of structural mechanisms was carried using high resolution electron microscopy (transmission and scanning transmission), electron diffraction and energy dispersive spectroscopy. Different non-stoichiometry mechanisms are observed, depending on the electronic structure and chemical properties of the doping elements. The specific behavior of the modulated double iron layer is discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000264644800001 Publication Date 2008-12-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1293-2558; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.811 Times cited 3 Open Access
Notes Esteem 026019 Approved Most recent IF: 1.811; 2009 IF: 1.675
Call Number UA @ lucian @ c:irua:76416 Serial 3437
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Author Bogaerts, A.
Title Effects of oxygen addition to argon glow discharges: a hybrid Monte Carlo-fluid modeling investigation Type A1 Journal article
Year (down) 2009 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B
Volume 64 Issue 11/12 Pages 1266-1279
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A hybrid model is developed for describing the effects of oxygen addition to argon glow discharges. The species taken into account in the model include Ar atoms in the ground state and the metastable level, O2 gas molecules in the ground state and two metastable levels, O atoms in the ground state and one metastable level, O3 molecules, Ar+, O+, O2+ and O− ions, as well as the electrons. The hybrid model consists of a Monte Carlo model for electrons and fluid models for the other plasma species. In total, 87 different reactions between the various plasma species are taken into account. Calculation results include the species densities and the importance of their production and loss processes, as well as the dissociation degree of oxygen. The effect of different O2 additions on these calculation results, as well as on the sputtering rates, is discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000272910300016 Publication Date 2009-10-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.241 Times cited 39 Open Access
Notes Approved Most recent IF: 3.241; 2009 IF: 2.719
Call Number UA @ lucian @ c:irua:79271 Serial 869
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Author Schalm, O.; van der Linden, V.; Frederickx, P.; Luyten, S.; van der Snickt, G.; Caen, J.; Schryvers, D.; Janssens, K.; Cornelis, E.; van Dyck, D.; Schreiner, M.
Title Enamels in stained glass windows: preparation, chemical composition, microstructure and causes of deterioration Type A1 Journal article
Year (down) 2009 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B
Volume 64 Issue 8 Pages 812-820
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Vision lab
Abstract Stained glass windows incorporating dark blue and purple enamel paint layers are in some cases subject to severe degradation while others from the same period survived the ravages of time. A series of dark blue, greenblue and purple enamel glass paints from the same region (Northwestern Europe) and from the same period (16early 20th centuries) has been studied by means of a combination of microscopic X-ray fluorescence analysis, electron probe micro analysis and transmission electron microscopy with the aim of better understanding the causes of the degradation. The chemical composition of the enamels diverges from the average chemical composition of window glass. Some of the compositions appear to be unstable, for example those with a high concentration of K2O and a low content of CaO and PbO. In other cases, the deterioration of the paint layers was caused by the less than optimal vitrification of the enamel during the firing process. Recipes and chemical compositions indicate that glassmakers of the 1617th century had full control over the color of the enamel glass paints they made. They mainly used three types of coloring agents, based on Co (dark blue), Mn (purple) and Cu (light-blue or greenblue) as coloring elements. Bluepurple enamel paints were obtained by mixing two different coloring agents. The coloring agent for redpurple enamel, introduced during the 19th century, was colloidal gold embedded in grains of lead glass.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000269995300018 Publication Date 2009-06-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.241 Times cited 28 Open Access
Notes Iuap Vi/6; Fwo; Goa Approved Most recent IF: 3.241; 2009 IF: 2.719
Call Number UA @ lucian @ c:irua:79647 Serial 1035
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Author Bogaerts, A.
Title Hybrid Monte Carlo: fluid model for studying the effects of nitrogen addition to argon glow discharges Type A1 Journal article
Year (down) 2009 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B
Volume 64 Issue 2 Pages 126-140
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract A computer model is developed for describing argon/nitrogen glow discharges. The species taken into account in the model include electrons, Ar atoms in the ground state and in the 4s metastable levels, N2 molecules in the ground state and in six different electronically excited levels, N atoms, Ar+ ions, N+, N2+, N3+ and N4+ ions. The fast electrons are simulated with a Monte Carlo model, whereas all other species are treated in a fluid model. 74 different chemical reactions are considered in the model. The calculation results include the densities of all the different plasma species, as well as information on their production and loss processes. The effect of different N2 additions, in the range between 0.1 and 10%, is investigated.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000263621300002 Publication Date 2008-12-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.241 Times cited 49 Open Access
Notes Approved Most recent IF: 3.241; 2009 IF: 2.719
Call Number UA @ lucian @ c:irua:72829 Serial 1525
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Author de Nolf, W.; Jaroszewicz, J.; Terzano, R.; Lind, O.C.; Salbu, B.; Vekemans, B.; Janssens, K.; Falkenberg, G.
Title Possibilities and limitations of synchrotron X-ray powder diffraction with double crystal and double multilayer monochromators for microscopic speciation studies Type A1 Journal article
Year (down) 2009 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B
Volume 64 Issue 8 Pages 775-781
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The performance of a combined microbeam X-ray fluorescence/X-ray powder diffraction (XRF/XRPD) measurement station at Hamburger Synchrotronstrahlungslabor (HASYLAB) Beamline L is discussed in comparison to that at European Synchrotron Radiation Facility (ESRF) ID18F/ID22. The angular resolution in the X-ray diffractograms is documented when different combinations of X-ray source, optics and X-ray diffraction detectors are employed. Typical angular resolution values in the range 0.30.5° are obtained at the bending magnet source when a pink beam form of excitation is employed. A similar setup at European Synchrotron Radiation Facility beamlines ID18F and ID22 allows to reach angular resolution values of 0.10.15°. In order to document the possibilities and limitations for speciation of metals in environmental materials by means of Hamburger Synchrotronstrahlungslabor Beamline L X-ray fluorescence/X-ray powder diffraction setup, two case studies are discussed, one involved in the identification of the crystal phases in which heavy metals such as chromium, iron, barium and lead are present in polluted soils of an industrial site (Val Basento, Italy) and another involved in the speciation of uranium in depleted uranium particles (Ceja Mountains, Kosovo). In the former case, the angular resolution is sufficient to allow identification of most crystalline phases present while in the latter case, it is necessary to dispose of an angular resolution of ca. 0.2° to distinguish between different forms of oxidized uranium.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000269995300010 Publication Date 2009-06-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547; 0038-6987 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.241 Times cited 7 Open Access
Notes Approved Most recent IF: 3.241; 2009 IF: 2.719
Call Number UA @ admin @ c:irua:79739 Serial 5778
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Author Denecke, M.A.; Brendebach, B.; de Nolf, W.; Falkenberg, G.; Janssens, K.; Simon, R.
Title Spatially resolved micro-X-ray fluorescence and micro-X-ray absorption fine structure study of a fractured granite bore core following a radiotracer experiment Type A1 Journal article
Year (down) 2009 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B
Volume 64 Issue 8 Pages 791-795
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Spatially resolved X-ray absorption and fluorescence investigation with a micrometer-scale resolution on actinide-containing samples provide information necessary for safety assessment of nuclear waste disposal. In this paper one example of such an experiment is presented. This example entails neptunium speciation in a fractured granite bore core from the Swedish Äspö Hard Rock Laboratory following a radiotracer experiment using µ-XAFS and µ-XRF. In order to probe micro-volumes below the surface in the granite samples and thereby avoid potential changes in the Np speciation during cutting of the bore core, a confocal irradiationdetection geometry is employed. µ-XAFS results for a selected granite bore core cross section with ~ 3 nmol Np/g reveal that Np, originally introduced as Np(V) in the tracer cocktail, is present in the granite in its reduced Np(IV) form. The Np(IV) is often present as particles, tens of µm in size. Elemental distribution maps show the tracer Np to be located in fissures and permeable channels not larger than 100 µm. The Np distribution appears often correlated with Zn also present in some fissures. We observe small granite fissures containing Fe (presumably Fe(II)), where we do not detect any Np. It is feasible that inflowing Np(V) has a shorter residence time in large fractures, while in the smaller fissures migration is slower, leading to longer residence times, i.e., reaction times, where it is reduced to less soluble Np(IV) and becomes thereby immobilized.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000269995300013 Publication Date 2009-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0584-8547; 0038-6987 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.241 Times cited 21 Open Access
Notes Approved Most recent IF: 3.241; 2009 IF: 2.719
Call Number UA @ admin @ c:irua:79740 Serial 5837
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Author Kips, R.; Pidduck, A.J.; Houlton, M.R.; Leenaers, A.; Mace, J.D.; Marie, O.; Pointurier, F.; Stefaniak, E.A.; Taylor, P.D.P.; van den Berghe, S.; van Espen, P.; Van Grieken, R.; Wellum, R.
Title Determination of fluorine in uranium oxyfluoride particles as an indicator of particle age Type A1 Journal article
Year (down) 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 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
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