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Author Vagov, A.; Croitoru, M.D.; Axt, V.M.; Kuhn, T.; Peeters, F. doi  openurl
  Title Real time path integrals in studies of quantum dots dynamics: non-monotonous decay rate and reappearance of rabi rotations Type P1 Proceeding
  Year 2008 Publication Path Integrals : New Trends and Perspectives, Proceedings Abbreviated Journal  
  Volume Issue Pages 57-62  
  Keywords P1 Proceeding; Condensed Matter Theory (CMT)  
  Abstract The dynamics of strongly confined laser driven semiconductor quantum dots coupled to phonons is studied theoretically by calculating the time evolution of the reduced density matrix using the path integral method. We explore the cases of long pulses, strong dot-phonon and dot-laser coupling and high temperatures, which up to now have been inaccessible. We find that the decay rate of the Rabi oscillations is a non-monotonic function of the laser field leading to the decay and reappearance of the Rabi oscillations in the field dependence of the dot exciton population.  
  Address  
  Corporate Author Thesis  
  Publisher World Scientific Place of Publication Singapore Editor  
  Language Wos 000264341000007 Publication Date (down) 2009-09-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:95702 Serial 2834  
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. pdf  doi
openurl 
  Title Influence of Al content on the properties of MgO grown by reactive magnetron sputtering Type A1 Journal article
  Year 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 (down) 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  
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Author Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. doi  openurl
  Title Ballistic current in metal-oxide-semiconductor field-effect transistors: the role of device topology Type A1 Journal article
  Year 2009 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 106 Issue 5 Pages 053702,1-053702,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this study we investigate the effect of device topology on the ballistic current in n-channel metal-oxide-semiconductor field-effect transistors. Comparison of the nanoscale planar and double-gate devices reveals that, down to a certain thickness of the double gate film, the ballistic current flowing in the double gate device is twice as large compared to its planar counterpart. On the other hand, further thinning of the film beyond this threshold is found to change noticeably the confinement and transport characteristics, which are strongly depending on the film material and the surface orientation. For double gate Ge and Si devices there exists a critical film thickness below which the transverse gate field is no longer effectively screened by the inversion layer electron gas and mutual inversion of the two gates is turned on. In the case of GaAs and other similar IIIV compounds, a decrease in the film thickness may drastically change the occupation of the L-valleys and therefore amend the transport properties. The simulation results show that, in both cases, the ballistic current and the transconductance are considerably enhanced.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000269850300052 Publication Date (down) 2009-09-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 3 Open Access  
  Notes Approved Most recent IF: 2.068; 2009 IF: 2.072  
  Call Number UA @ lucian @ c:irua:79744 Serial 214  
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Author Abakumov, A.M.; King, G.; Laurinavichute, V.K.; Rozova, M.G.; Woodward, P.M.; Antipov, E.V. doi  openurl
  Title The crystal structure of \alpha-K3AIF6: elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework Type A1 Journal article
  Year 2009 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 48 Issue 19 Pages 9336-9344  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The crystal structure of α-K3AlF6 was solved and refined from a combination of powder X-ray and neutron diffraction data (a = 18.8385(3)Å, c = 33.9644(6)Å, S.G. I41/a, Z = 80, RP(X-ray) = 0.037, RP(neutron) = 0.053). The crystal structure is of the A2BB′X6 elpasolite type with the a = b ≈ ae√5, c = 4ae superstructure (ae, parameter of the elpasolite subcell) and rock-salt-type ordering of the K and Al cations over the B and B′ positions, respectively. The remarkable feature of α-K3AlF6 is a rotation of 2/5 of the AlF6 octahedra by π/4 around one of the crystal axes of the elpasolite subcell, coinciding with the 4-fold symmetry axes of the AlF6 octahedra. The rotation of the AlF6 octahedra replaces the corner-sharing between the K and Al polyhedra by edge-sharing, resulting in an increase of coordination numbers of the K cations at the B positions up to 7 and 8. Due to significant deformations of the K polyhedra, the corner-sharing connectivity of the octahedral elpasolite framework is broken and the rotations of the AlF6 octahedra do not have a cooperative character. Elpasolites and double perovskites with similar structural organization are discussed. The difference in ionic radii of the B and B′ cations as well as the tolerance factor are proposed to be the parameters governing the formation of elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Easton, Pa Editor  
  Language Wos 000270091000039 Publication Date (down) 2009-09-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.857 Times cited 20 Open Access  
  Notes Approved Most recent IF: 4.857; 2009 IF: 4.657  
  Call Number UA @ lucian @ c:irua:79733 Serial 568  
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Author Szafran, B.; Poniedziałek, M.R.; Peeters, F.M. doi  openurl
  Title Violation of Onsager symmetry for a ballistic channel Coulomb coupled to a quantum ring Type A1 Journal article
  Year 2009 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett  
  Volume 87 Issue 4 Pages 47002,1-47002,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate a scattering of electron which is injected individually into an empty ballistic channel containing a cavity that is Coulomb coupled to a quantum ring charged with a single electron. We solve the time-dependent Schrödinger equation for the electron pair with an exact account for the electron-electron correlation. Absorption of energy and angular momentum by the quantum ring is not an even function of the external magnetic field. As a consequence we find that the electron backscattering probability is asymmetric in the magnetic field and thus violates Onsager symmetry.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Paris Editor  
  Language Wos 000270146400017 Publication Date (down) 2009-09-02  
  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 4 Open Access  
  Notes Approved Most recent IF: 1.957; 2009 IF: 2.893  
  Call Number UA @ lucian @ c:irua:79734 Serial 3847  
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Author Zha, G.-Q.; Chen, Y.; Peeters, F.M.; Zhou, S.-P. url  doi
openurl 
  Title Impurity-induced modulations of orders in d-wave superconductors Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 6 Pages 064518,1-064518,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By using a model Hamiltonian with competing antiferromagnetic (AFM) and d-wave superconductivity orders, the impurity-induced structures of orders in d-wave superconductors is investigated. We find that the transition between one-dimensional stripe and two-dimensional checkerboardlike modulation around a single nonmagnetic impurity can take place as the strength of the AFM interaction U or the impurity scattering strength V0 is varied. It is also found that the impurity-induced stripe can first transit to checkerboardlike modulation and then disappears with increasing the next-nearest-neighbor hopping strength |t|. Phase diagrams of V0 versus U and |t| for various modulations of the spin order are presented. In addition, the quantum interference effect on the modulations of orders due to two strong nonmagnetic impurities is briefly examined, and the checkerboardlike and quasistripe patterns can occur depending on the sites where two impurities are placed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000269638800074 Publication Date (down) 2009-09-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 3 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:78293 Serial 1572  
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Author Cao, S.; Nishida, M.; Somsen, C.; Eggeler, G.; Schryvers, D. doi  openurl
  Title 3D FIB/SEM study of Ni4Ti3 precipitates in Ni-Ti alloys with different thermal-mechanical histories Type P1 Proceeding
  Year 2009 Publication Abbreviated Journal  
  Volume Issue Pages 02004,1-02004,6  
  Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)  
  Abstract The three-dimensional size, morphology and distribution of Ni4Ti3 precipitates growing in binary Ni-rich Ni-Ti alloys have been investigated via a slice view procedure in a Dual-Beam FIB/SEM system, in order to better stress-free Ni50.8Ti49.2 alloy with all four variants of precipitates and a compressed Ni51Ti49 alloy with aligned precipitates in one family were studied. The Ni4Ti3 precipitates reach a volume fraction of 9.6% in the reconstructed region of the stress-free alloy and 4.3% in the compressed one. In both cases, the mean volume, specific surface area, sphericity and aspect ratio of the precipitates are calculated and the Pair Distribution Functions of the precipitates are obtained. It is shown that most precipitates in the stress-free sample grow larger and have a more lenticular shape, while those in the compressed sample are more cylindrical. Deviations from these ideal shapes reveal internal steps in the stress-free sample and lamellae formation in the compressed one.  
  Address  
  Corporate Author Thesis  
  Publisher Edp Place of Publication Coutaboeuf Editor  
  Language Wos 000274582300008 Publication Date (down) 2009-08-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 1 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:81950 c:irua:81950 Serial 14  
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Author Idrissi, H.; Schryvers, D.; Salje, E.K.H.; Zhang, H.; Carpenter, M.A.; Moya, X. url  doi
openurl 
  Title Pinning of the martensitic microstructures by dislocations in Cu74.08Al23.13Be2.79 Type P1 Proceeding
  Year 2009 Publication Abbreviated Journal  
  Volume Issue Pages 02029,1-02029,5  
  Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)  
  Abstract A single crystal of Cu74.08Al23.13Be2.79 undergoes a martensitic phase transition at 246K and 232K under heating and cooling, respectively. Surprisingly, the martensite phase is elastically much harder than the austenite phase showing that interfaces between various crystallographic variants are strongly pinned and can not be moved by external stress while the phase boundary between the austenite and martensite regions in the sample remains mobile. This unusual behavior was revealed by Dynamical Mechanical Analysis and Resonant Ultrasound Spectroscopy. Transmission Electron Microscopy shows that the pinning is generated by dislocations, which are inherited from the austenite phase. Such dislocations can hinder the movement of stacking faults in the 18R martensite structure or twin boundaries between martensite variants.  
  Address  
  Corporate Author Thesis  
  Publisher Edp Place of Publication Coutaboeuf Editor  
  Language Wos 000274582300033 Publication Date (down) 2009-08-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 2 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:81952 Serial 2626  
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Author Launois, P.; Chorro, M.; Verberck, B.; Albouy, P.-A.; Rouzière, S.; Colson, D.; Forget, A.; Noé, L.; Kataura, H.; Monthioux, M.; Cambedouzou, J. pdf  doi
openurl 
  Title Transformation of C70 peapods into double walled carbon nanotubes Type A1 Journal article
  Year 2010 Publication Carbon Abbreviated Journal Carbon  
  Volume 48 Issue 1 Pages 89-98  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract X-ray diffraction studies comparing the transformation of C(60) and C(70) peapods into double walled carbon nanotubes are presented. The structures of the as-formed DWCNTs are strikingly similar, showing that they are not dependent on the nature of the fullerene precursor. High temperature X-ray diffraction measurements of C(70) peapods below the coalescence temperature show that confined C(70) molecules in large tubes undergo an orientational. transition to free rotations. Fast re-orientations of C(70) molecules allow cyclo-addition between adjacent fullerenes to form, in good agreement with the mechanism of coalescence proposed in the literature for C(60) molecules. (C) 2009 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000272018800012 Publication Date (down) 2009-08-30  
  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 27 Open Access  
  Notes ; ; Approved Most recent IF: 6.337; 2010 IF: 4.896  
  Call Number UA @ lucian @ c:irua:94389 Serial 3696  
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Author Zarenia, M.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. doi  openurl
  Title Electrostatically confined quantum rings in bilayer graphene Type A1 Journal article
  Year 2009 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 9 Issue 12 Pages 4088-4092  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We propose a new system where electron and hole states are electrostatically confined into a quantum ring in bilayer graphene. These structures can be created by tuning the gap of the graphene bilayer using nanostructured gates or by position-dependent doping. The energy levels have a magnetic field (B0) dependence that is strikingly distinct from that of usual semiconductor quantum rings. In particular, the eigenvalues are not invariant under a B0 ¨ −B0 transformation and, for a fixed total angular momentum index m, their field dependence is not parabolic, but displays two minima separated by a saddle point. The spectra also display several anticrossings, which arise due to the overlap of gate-confined and magnetically confined states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington Editor  
  Language Wos 000272395400023 Publication Date (down) 2009-08-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.712 Times cited 42 Open Access  
  Notes Approved Most recent IF: 12.712; 2009 IF: 9.991  
  Call Number UA @ lucian @ c:irua:80318 Serial 1024  
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Author Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. url  doi
openurl 
  Title Tunneling-lifetime model for metal-oxide-semiconductor structures Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 8 Pages 085315,1-085315,10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this paper we investigate the basic physics of charge carriers (electrons) leaking out of the inversion layer of a metal-oxide-semiconductor capacitor with a biased gate. In particular, we treat the gate leakage current as resulting from two combined processes: (1) the time-dependent decay of electron wave packets representing the inversion-layer charge and (2) the local generation of new electrons replacing those that have leaked away. As a result, the gate current simply emerges as the ratio of the total charge in the inversion layer to the tunneling lifetime. The latter is extracted from the quantum dynamics of the decaying wave packets, while the generation rate is incorporated as a phenomenological source term in the continuity equation. Not only do the gate currents calculated with this model agree very well with experiment, the model also provides an onset to solve the paradox of the current-free bound states representing the resonances of the Schrödinger equation that governs the fully coupled metal-oxide-semiconductor system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000269639300076 Publication Date (down) 2009-08-21  
  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 2 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:78294 Serial 3763  
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Author Dhong, H.M.; Zhang, J.; Peeters, F.M.; Xu, W. doi  openurl
  Title Optical conductance and transmission in bilayer graphene Type A1 Journal article
  Year 2009 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 106 Issue 4 Pages 043103,1-043103,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We present a theoretical study of the optoelectronic properties of bilayer graphene. The optical conductance and transmission coefficient are calculated using the energy-balance equation derived from a Boltzmann equation for an air/graphene/dielectric-wafer system. For short wavelengths (<0.2 µm), we obtain the universal optical conductance =e2/(2). Interestingly, there exists an optical absorption window in the wavelength range 10100 µm, which is induced by different transition energies required for inter- and intra-band optical absorptions in the presence of the MossBurstein effect. As a result, the position and width of this absorption window depend sensitively on temperature, carrier density, and sample mobility of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000270083800004 Publication Date (down) 2009-08-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 11 Open Access  
  Notes Approved Most recent IF: 2.068; 2009 IF: 2.072  
  Call Number UA @ lucian @ c:irua:79315 Serial 2472  
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Author Wang, M.; Chang, K.; Wang, L.G.; Dai, N.; Peeters, F.M. doi  openurl
  Title Crystallographic plane tuning of charge and spin transport in semiconductor quantum wires Type A1 Journal article
  Year 2009 Publication Nanotechnology Abbreviated Journal Nanotechnology  
  Volume 20 Issue 36 Pages 365202,1-365202,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate theoretically the charge and spin transport in quantum wires grown along different crystallographic planes in the presence of the Rashba spinorbit interaction (RSOI) and the Dresselhaus spinorbit interaction (DSOI). We find that changing the crystallographic planes leads to a variation of the anisotropy of the conductance due to a different interplay between the RSOI and DSOI, since the DSOI is induced by bulk inversion asymmetry, which is determined by crystallographic plane. This interplay depends sensitively on the crystallographic planes, and consequently leads to the anisotropic charge and spin transport in quantum wires embedded in different crystallographic planes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000269077000003 Publication Date (down) 2009-08-19  
  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 14 Open Access  
  Notes Approved Most recent IF: 3.44; 2009 IF: 3.137  
  Call Number UA @ lucian @ c:irua:78933 Serial 588  
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Author Berdiyorov, G.R.; Yu, S.H.; Xiao, Z.L.; Peeters, F.M.; Hua, J.; Imre, A.; Kwok, W.K. url  doi
openurl 
  Title Effect of sample geometry on the phase boundary of a mesoscopic superconducting loop Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 6 Pages 064511,1-064511,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We studied the effect of sample geometry on the evolution of the superconducting state in nanoscale Nb circular and square loops by transport measurements. A multistage resistive transition with temperature is found for both samples, which is related to the effect of contact leads made from the same superconducting material. The H-T phase diagrams close to Tc0 show clear periodic oscillations on top of a parabolic background, i.e., Little-Parks effect. However, the amplitude of the oscillations decreases faster in the circular loop compared to the one in the square sample. Numerical simulations are conducted within the nonlinear Ginzburg-Landau theory to show the effect of sample geometry on the nucleation of superconductivity in superconducting loop structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000269638800067 Publication Date (down) 2009-08-17  
  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 21 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:78292 Serial 833  
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Author van der Linden, V.; Schalm, O.; Houbraken, J.; Thomas, M.; Meesdom, E.; Devos, A.; van Dooren, R.; Nieuwdorp, H.; Janssen, E.; Janssens, K. doi  openurl
  Title Chemical analysis of 16th to 19th century Limoges School painted enamel objects in three museums of the Low Countries Type A1 Journal article
  Year 2010 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom  
  Volume 39 Issue 2 Pages 112-121  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract In this study, the results of analysing of a series of 16th-19th century painted enamel objects of the Limoges School currently in collections in three Dutch and Flemish museums by means of portable and micro x-ray fluorescence analysis (PXRF and µ-XRF) and electron probe micro analysis (EPMA) are presented. The aim of the investigation was the authentication of specific pieces. Therefore, the glass compositions as well as the (glass) colouring agents used by the Limoges' artists were studied as a function of the age of the objects. Due to the evolution of these properties, it is possible to approximately date these objects based on their chemical composition. The complete émail peint collection of the Museum Boijmans-Van Beuningen (Rotterdam, The Netherlands), consisting of 20 émail peint plaques, was analysed with µ-XRF. Quantitative information was obtained by EPMA analysis of 15 enamel fragments of objects from museum and private collections in the Low Countries. PXRF analyses were performed on the painted enamel collection of the Antwerp Vleeshuis Museum (13 objects) and the Mayer van den Bergh Museum (4 objects) and on a set of 18 plaques that were donated to the Boijmans-Van Beuningen Museum by a private collector. The results obtained by means of EPMA, µ-XRF and PXRF proved to be useful in the discrimination of 16th century painted enamel objects from those of the19th century. From a total of 70 objects examined, 2 objects (OM964A and OM993) featured a chemical signature that deviated from the published literature composition and pigment use consistent with its presumed period of manufacture.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000275959400007 Publication Date (down) 2009-08-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0049-8246 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.298 Times cited 8 Open Access  
  Notes ; ; Approved Most recent IF: 1.298; 2010 IF: 1.661  
  Call Number UA @ admin @ c:irua:82325 Serial 5509  
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Author Zhang, H.; Yang, J.-H.; Shpanchenko, R.V.; Abakumov, A.M.; Hadermann, J.; Clérac, R.; Dikarev, E.V. doi  openurl
  Title New class of single-source precursors for the synthesis of main group-transition metal oxides: heterobimetallic Pb-Mn \beta-diketonates Type A1 Journal article
  Year 2009 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 48 Issue 17 Pages 8480-8488  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Heterometallic lead−manganese â-diketonates have been isolated in pure form by several synthetic methods that include solid-state and solution techniques. Two compounds with different Pb/Mn ratios, PbMn2(hfac)6 (1) and PbMn(hfac)4 (2) (hfac = hexafluoroacetylacetonate), can be obtained in quantitative yield by using different starting materials. Single crystal X-ray investigation revealed that the solid-state structure of 1 contains trinuclear molecules in which lead metal center is sandwiched between two [Mn(hfac)3] units, while 2 consists of infinite chains of alternating [Pb(hfac)2] and [Mn(hfac)2] fragments. The heterometallic structures are held together by strong Lewis acid−base interactions between metal atoms and diketonate ligands acting in chelating-bridging fashion. Spectroscopic investigation confirmed the retention of heterometallic structures in solutions of non-coordinating solvents as well as upon sublimation-deposition procedure. Thermal decomposition of heterometallic diketonates has been systematically investigated in a wide range of temperatures and annealing times. For the first time, it has been shown that thermal decomposition of heterometallic diketonates results in mixed-metal oxides, while both the structure of precursors and the thermolysis conditions have a significant influence on the nature of the resulting oxides. Five different Pb−Mn oxides have been detected by X-ray powder diffraction when studying the decomposition of 1 and 2 in the temperature range 500−800 °C. The phase that has been previously reported as Pb0.43MnO2.18 was synthesized in the pure form by decomposition of 1, and crystallographically characterized. The orthorhombic unit cell parameters of this oxide, obtained by electron diffraction technique, have been subsequently refined using X-ray powder diffraction data. Besides that, a previously unknown lead−manganese oxide has been obtained at low temperature decomposition and short annealing times. The parameters of its monoclinically distorted unit cell have been determined. The EDX analysis revealed that this compound has a Pb/Mn ratio close to 1:4 and contains no appreciable amount of fluorine.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Easton, Pa Editor  
  Language Wos 000269313500056 Publication Date (down) 2009-08-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.857 Times cited 28 Open Access  
  Notes Approved Most recent IF: 4.857; 2009 IF: 4.657  
  Call Number UA @ lucian @ c:irua:78486 Serial 2308  
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Author Hao, Y.L.; Djotyan, A.P.; Avetisyan, A.A.; Peeters, F.M. url  doi
openurl 
  Title Shallow donor states near a semiconductor-insulator-metal interface Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 3 Pages 035329,1-035329,10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The lowest energy electronic states of a donor located near a semiconductor-insulator-metal interface are investigated within the effective mass approach. The effect of the finite thickness of the insulator between the semiconductor and the metallic gate on the energy levels is studied. The lowest energy states are obtained through a variational approach, which takes into account the influence of all image charges that arise due to the presence of the metallic and the dielectric interfaces. We compare our results with a numerical exact calculation using the finite element technique.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000268617800101 Publication Date (down) 2009-07-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 22 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77950 Serial 2989  
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Author Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. doi  isbn
openurl 
  Title Tuning the superconducting properties of nanomaterials Type H1 Book chapter
  Year 2009 Publication Abbreviated Journal  
  Volume Issue Pages 1-14  
  Keywords H1 Book chapter; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT)  
  Abstract Electron continement and its effect on the superconducting-to-normal phase transition driven by a magentic field and/or a current is studied in nanowires. Our investigation is based on a self-consistent numerical solution of the Bogoliubov-de Gennes equations. We find that in a parallel magneitc field and/or in the presence of a supercurrent the transition from the superconducting to the normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magentic field exhibits quantum-size oscillations with pronounced resonant enhancements as a function of the wire radius.  
  Address  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Dordrecht Editor  
  Language Wos 000274282900001 Publication Date (down) 2009-07-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1874-6500; ISBN 978-90-481-3118-1 Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:99226 Serial 3761  
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Author Lepoittevin, C.; Hadermann, J.; Malo, S.; Pérez, O.; Van Tendeloo, G.; Hervieu, M. pdf  doi
openurl 
  Title Two variants of the 1/2[110]p(203)p crystallographic shear structures: the phasoid Sr0.61Pb0.18(Fe0.75Mn0.25)O2.29 Type A1 Journal article
  Year 2009 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 48 Issue 17 Pages 8257-8262  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract For the composition (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29, a new modulated crystallographic shear structure, related to perovskite, has been synthesized and structurally characterized by transmission electron microscopy. The structure can be described using a monoclinic supercell with cell parameters am = 27.595(2) Å, bm = 3.8786(2) Å, cm = 13.3453(9) Å, and βm = 100.126(5)°, refined from powder X-ray diffraction data. The incommensurate crystallographic shear phases require an alternative approach using the superspace formalism. This allows a unified description of the incommensurate phases from a monoclinically distorted perovskite unit cell and a modulation wave vector. The structure deduced from the high-resolution transmission electron microscopy and high-angle annular dark-field−scanning transmission electron microscopy images is that of a 1/2[110]p(203)p crystallographic shear structure. The structure follows the concept of a phasoid, with two coexisting variants with the same unit cell. The difference is situated at the translational interface, with the local formation of double (phase 2) or single (phase 1) tunnels, where the Pb cations are likely located.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Easton, Pa Editor  
  Language Wos 000269313500032 Publication Date (down) 2009-07-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.857 Times cited 11 Open Access  
  Notes Esteem 026019 Approved Most recent IF: 4.857; 2009 IF: 4.657  
  Call Number UA @ lucian @ c:irua:78482 Serial 3786  
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Author Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. url  doi
openurl 
  Title Superconducting nanowires: interplay of discrete transverse modes with supercurrent Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 2 Pages 024513,1-024513,11  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract From a numerical solution of the Bogoliubov-de Gennes equations, we investigate an interplay of the transverse discrete modes with a longitudinal supercurrent in a metallic cylindrical superconducting nanowire. The superconductor-to-normal transition induced by a longitudinal superflow of electrons is found to occur as a cascade of jumps in the order parameter (supercurrent and superfluid density) as a function of the superfluid velocity for diameters d<1015 nm (for Al parameters) and sufficiently low temperatures T<0.30.4Tc, with Tc the critical temperature. When approaching Tc, the jumps are smoothed into steplike but continuous drops. A similar picture occurs for d>1520 nm. Only when the diameter exceeds 5070 nm the quantum-size cascades are fully washed out, and we arrive at the mesoscopic regime. Below this regime the critical current density jc exhibits the quantum-size oscillations with pronounced resonant enhancements: the smaller the diameter, the more significant is the enhancement. Thickness fluctuations of real samples will smooth out such oscillations into an overall growth of jc with decreasing nanowire diameter.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000268617500092 Publication Date (down) 2009-07-22  
  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 21 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77949 Serial 3358  
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Author Schweigert, V.A.; Peeters, F.M. pdf  doi
openurl 
  Title Dynamics of a finite classical two-dimensional system Type A1 Journal article
  Year 1994 Publication Superlattices and microstructures Abbreviated Journal Superlattice Microst  
  Volume 16 Issue 3 Pages 243-247  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The spectral properties of a classical two-dimensional (2D) cluster of charged particles which are confined by a quadratic potential are calculated. Using the method of Newton optimization we obtain the ground state and the metastable states. For a given configuration the eigenvectors and eigenfrequencies for the normal modes are obtained using the Householder diagonalization technique for the dynamical matrix whose elements are the second derivative of the potential energy. For small clusters the lowest excitation corresponds to an intershell rotation. Magic numbers are associated to clusters which are most stable against intershell rotation. For large clusters the lowest excitation is a vortex/anti-vortex pair.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos A1994QE75400007 Publication Date (down) 2009-07-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0749-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.097 Times cited 4 Open Access  
  Notes Approved no  
  Call Number UA @ lucian @ c:irua:99951 Serial 772  
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Author Hadermann, J.; Abakumov, A.M.; Adkin, J.J.; Hayward, M.A. doi  openurl
  Title Topotactic reduction as a route to new close-packed anion deficient perovskites: structure and magnetism of 4H-BaMnO2+x Type A1 Journal article
  Year 2009 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc  
  Volume 131 Issue 30 Pages 10598-10604  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The anion-deficient perovskite 4H-BaMnO2+x has been obtained by a topotactic reduction, with LiH, of the hexagonal perovskite 4H-BaMnO3−x. The crystal structure of 4H-BaMnO2+x was solved using electron diffraction and X-ray powder diffraction and further refined using neutron powder diffraction (S.G. Pnma, a = 10.375(2) Å, b = 9.466(2) Å, c = 11.276(3) Å, at 373 K). The orthorhombic superstructure arises from the ordering of oxygen vacancies within a 4H (chch) stacking of close packed c-type BaO2.5 and h-type BaO1.5 layers. The ordering of the oxygen vacancies transforms the Mn2O9 units of face-sharing MnO6 octahedra into Mn2O7 (two corner-sharing tetrahedra) and Mn2O6 (two edge-sharing tetrahedra) groups. The Mn2O7 and Mn2O6 groups are linked by corner-sharing into a three-dimensional framework. The structures of the BaO2.5 and BaO1.5 layers are different from those observed previously in anion-deficient perovskites providing a new type of order pattern of oxygen atoms and vacancies in close packed structures. Magnetization measurements and neutron diffraction data reveal 4H-BaMnO2+x adopts an antiferromagnetically ordered state below TN ≈ 350 K.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000268644400056 Publication Date (down) 2009-07-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-7863;1520-5126; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.858 Times cited 25 Open Access  
  Notes Approved Most recent IF: 13.858; 2009 IF: 8.580  
  Call Number UA @ lucian @ c:irua:77928 Serial 3681  
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Author Leenaerts, O.; Partoens, B.; Peeters, F.M. url  doi
openurl 
  Title Water on graphene: hydrophobicity and dipole moment using density functional theory Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 79 Issue 23 Pages 235440,1-235440,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We apply density-functional theory to study the adsorption of water clusters on the surface of a graphene sheet and find i) graphene is highly hydrophobic and ii) adsorbed water has very little effect on the electronic structure of graphene. A single water cluster on graphene has a very small average dipole moment which is in contrast with an ice layer that exhibits a strong dipole moment.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000267699500147 Publication Date (down) 2009-06-29  
  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 292 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77693 Serial 3904  
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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. pdf  doi
openurl 
  Title Enamels in stained glass windows: preparation, chemical composition, microstructure and causes of deterioration Type A1 Journal article
  Year 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 (down) 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 Abakumov, A.M.; Hadermann, J.; Tsirlin, A.A.; Tan, H.; Verbeeck, J.; Zhang, H.; Dikarev, E.V.; Shpanchenko, R.V.; Antipov, E.V. doi  openurl
  Title Original close-packed structure and magnetic properties of the Pb4Mn9O20 manganite Type A1 Journal article
  Year 2009 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 182 Issue 8 Pages 2231-2238  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The crystal structure of the Pb4Mn9O20 compound (previously known as Pb0.43MnO2.18) was solved from powder X-ray diffraction, electron diffraction, and high resolution electron microscopy data (S.G. Pnma, a=13.8888(2) Å, b=11.2665(2) Å, c=9.9867(1) Å, RI=0.016, RP=0.047). The structure is based on a 6H (cch)2 close packing of pure oxygen h-type (O16) layers alternating with mixed c-type (Pb4O12) layers. The Mn atoms occupy octahedral interstices formed by the oxygen atoms of the close-packed layers. The MnO6 octahedra share edges within the layers, whereas the octahedra in neighboring layers are linked through corner sharing. The relationship with the closely related Pb3Mn7O15 structure is discussed. Magnetization measurements reveal a peculiar magnetic behavior with a phase transition at 52 K, a small net magnetization below the transition temperature, and a tendency towards spin freezing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000269066400035 Publication Date (down) 2009-06-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.299 Times cited 5 Open Access  
  Notes The authors are grateful to Christoph Geibel for the help in magnetization measurements. A.Ts. acknowledges MPI CKS for hospitality and financial support during the stay. E.D. thanks the National Science Foundation (CHE-0718900) for financial support. This work was supported by the Russian Foundation of Basic Research (RFBR Grants 07-03-00664-a, 06-03-90168-a and 07-03-00890-a). The authors acknowledge financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. Approved Most recent IF: 2.299; 2009 IF: 2.340  
  Call Number UA @ lucian @ c:irua:78935UA @ admin @ c:irua:78935 Serial 2529  
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Author Matulis, A.; Peeters, F.M. doi  openurl
  Title Analogy between one-dimensional chain models and graphene Type A1 Journal article
  Year 2009 Publication American journal of physics Abbreviated Journal Am J Phys  
  Volume 77 Issue 7 Pages 595-601  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electron and hole spectrum in single and bilayer graphene is derived from known one-dimensional models, and the relation between the spectrum and symmetry of the lattice is shown.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000266976000003 Publication Date (down) 2009-06-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-9505; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.069 Times cited 11 Open Access  
  Notes Approved Most recent IF: 1.069; 2009 IF: 0.779  
  Call Number UA @ lucian @ c:irua:77381 Serial 97  
Permanent link to this record
 

 
Author Denecke, M.A.; Brendebach, B.; de Nolf, W.; Falkenberg, G.; Janssens, K.; Simon, R. doi  openurl
  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 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 (down) 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 Dominiczak, M.; Ruyter, A.; Limelette, P.; Monot-Laffez, I.; Giovannelli, F.; Rossell, M.D.; Van Tendeloo, G. pdf  doi
openurl 
  Title Effects of nanocracks on the magnetic and electrical properties of La0.8Sr0.2MnO3 single crystals Type A1 Journal article
  Year 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 (down) 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  
Permanent link to this record
 

 
Author Szafran, B.; Nowak, M.P.; Bednarek, S.; Chwiej, T.; Peeters, F.M. url  doi
openurl 
  Title Selective suppression of Dresselhaus or Rashba spin-orbit coupling effects by the Zeeman interaction in quantum dots Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 79 Issue 23 Pages 235303,1-235303,13  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study single- and two-electron parabolic quantum dots in the presence of linear Dresselhaus and Rashba spin-orbit interactions. Contributions of both types of spin-orbit coupling are investigated in the context of the spin polarization of the system at high magnetic fields. We demonstrate that for negative Landé factors the effect of the Dresselhaus coupling is suppressed at high magnetic field, which for structures without inversion asymmetry leads to a completely spin-polarized system and a strict antisymmetry of the wave functions with respect to the interchange of spatial-electron coordinates. For negative Landé factor the Rashba coupling is preserved at high field and consequently the spin polarization of the systems as well as the spatial antisymmetry of the two-electron wave function remain approximate.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000267699500073 Publication Date (down) 2009-06-02  
  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 13 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77691 Serial 2969  
Permanent link to this record
 

 
Author Van Aert, S.; Verbeeck, J.; Erni, R.; Bals, S.; Luysberg, M.; van Dyck, D.; Van Tendeloo, G. pdf  doi
openurl 
  Title Quantitative atomic resolution mapping using high-angle annular dark field scanning transmission electron microscopy Type A1 Journal article
  Year 2009 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 109 Issue 10 Pages 1236-1244  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract A model-based method is proposed to relatively quantify the chemical composition of atomic columns using high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. The method is based on a quantification of the total intensity of the scattered electrons for the individual atomic columns using statistical parameter estimation theory. In order to apply this theory, a model is required describing the image contrast of the HAADF STEM images. Therefore, a simple, effective incoherent model has been assumed which takes the probe intensity profile into account. The scattered intensities can then be estimated by fitting this model to an experimental HAADF STEM image. These estimates are used as a performance measure to distinguish between different atomic column types and to identify the nature of unknown columns with good accuracy and precision using statistical hypothesis testing. The reliability of the method is supported by means of simulated HAADF STEM images as well as a combination of experimental images and electron energy-loss spectra. It is experimentally shown that statistically meaningful information on the composition of individual columns can be obtained even if the difference in averaged atomic number Z is only 3. Using this method, quantitative mapping at atomic resolution using HAADF STEM images only has become possible without the need of simultaneously recorded electron energy loss spectra.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000270015200004 Publication Date (down) 2009-05-28  
  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 166 Open Access  
  Notes Fwo; Esteem 026019 Approved Most recent IF: 2.843; 2009 IF: 2.067  
  Call Number UA @ lucian @ c:irua:78585UA @ admin @ c:irua:78585 Serial 2748  
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