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Author Li, B.; Magnus, W.; Peeters, F.M. url  doi
openurl 
  Title Tunable exciton Aharonov-Bohm effect in a quantum ring Type A1 Journal article
  Year 2010 Publication Journal of physics : conference series T2 – Proceedings of the 11th International Conference on Optics of Excitons in Confined Systems, September 7-11, 2009, Spain / Vina, L. [edit.]; et al. [edit.] Abbreviated Journal  
  Volume 210 Issue 1 Pages 012030,1-01203,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We studied the optical Aharonov-Bohm effect for an exciton in a semiconductor quantum ring. A perpendicular electric field applied to a quantum ring with large height, is able to tune the exciton ground state energy such that it exhibits a weak observable Aharonov-Bohm oscillations. This Aharonov-Bohm effect is tunable in strength and period.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Bristol Editor  
  Language Wos 000289715800242 Publication Date 2010-03-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6596; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 3 Open Access  
  Notes ; ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:89950 Serial 3741  
Permanent link to this record
 

 
Author Goffin, A.-L.; Duquesne, E.; Raquez, J.-M.; Miltner, H.E.; Ke, X.; Alexandre, M.; Van Tendeloo, G.; van Mele, B.; Dubois, P. pdf  doi
openurl 
  Title From polyester grafting onto POSS nanocage by ring-opening polymerization to high performance polyester/POSS nanocomposites Type A1 Journal article
  Year 2010 Publication Journal of materials chemistry Abbreviated Journal J Mater Chem  
  Volume 20 Issue 42 Pages 9415-9422  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Polyester-grafted polyhedral oligomeric silsesquioxane (POSS) nanohybrids selectively produced by ring-opening polymerization of ε-caprolactone and L,L-lactide (A.-L. Goffin, E. Duquesne, S. Moins, M. Alexandre, Ph. Dubois, Eur. Polym. Journal, 2007, 43, 4103) were studied as masterbatches by melt-blending within their corresponding commercial polymeric matrices, i.e., poly(ε-caprolactone) (PCL) and poly(L,L-lactide) (PLA). For the sake of comparison, neat POSS nanoparticles were also dispersed in PCL and PLA. The objective was to prepare aliphatic polyester-based nanocomposites with enhanced crystallization behavior, and therefore, enhanced thermo-mechanical properties. Wide-angle X-ray scattering and transmission electron microscopy attested for the dispersion of individualized POSS nanoparticles in the resulting nanocomposite materials only when the polyester-grafted POSS nanohybrid was used as a masterbatch. The large impact of such finely dispersed (grafted) nanoparticles on the crystallization behavior for the corresponding polyester matrices was noticed, as evidenced by differential scanning calorimetry analysis. Indeed, well-dispersed POSS nanoparticles acted as efficient nucleating sites, significantly increasing the crystallinity degree of both PCL and PLA matrices. As a result, a positive impact on thermo-mechanical properties was highlighted by dynamic mechanical thermal analysis.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Cambridge Editor  
  Language Wos 000283264500017 Publication Date 2010-06-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0959-9428;1364-5501; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 42 Open Access  
  Notes Fwo; Iap-6 Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:85784 Serial 1284  
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Author Yang, T.; Abakumov, A.M.; Hadermann, J.; Van Tendeloo, G.; Nowik, I.; Stephens, P.W.; Hamberger, J.; Tsirlin, A.A.; Ramanujachary, K.V.; Lofland, S.; Croft, M.; Ignatov, A.; Sun, J.; Greenblatt, M. pdf  doi
openurl 
  Title _BiMnFe2O6, a polysynthetically twinned hcp MO structure Type A1 Journal article
  Year 2010 Publication Chemical science Abbreviated Journal Chem Sci  
  Volume 1 Issue 6 Pages 751-762  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The most efficient use of spatial volume and the lowest potential energies in the metal oxide structures are based on cubic close packing (ccp) or hexagonal close packing (hcp) of anions with cations occupying the interstices. A promising way to tune the composition of close packed oxides and design new compounds is related to fragmenting the parent structure into modules by periodically spaced planar interfaces, such as twin planes at the unit cell scale. The unique crystal chemistry properties of cations with a lone electron pair, such as Bi3+ or Pb2+, when located at interfaces, enables them to act as chemical scissors, to help relieve configurational strain. With this approach, we synthesized a new oxide, BiMnFe2O6, where fragments of the hypothetical hcp oxygen-based MO structure (the NiAs structure type), for the first time, serve as the building modules in a complex transition metal oxide. Mn3+ and Fe3+ ions are randomly distributed in two crystallographically independent sites (M1 and M2). The structure consists of quasi two-dimensional blocks of the 2H hexagonal close packed MO structure cut along the (114) crystal plane of the hcp lattice and stacked along the c axis. The blocks are related by a mirror operation that allows BiMnFe2O6 to be considered as a polysynthetically twinned 2H hcp MO structure. The transition to an AFM state with an incommensurate spin configuration at [similar] 212 K is established by 57Fe Mössbauer spectroscopy, magnetic susceptibility, specific heat and low temperature powder neutron diffraction.  
  Address  
  Corporate Author Thesis  
  Publisher Royal Society of Chemistry Place of Publication (up) Cambridge Editor  
  Language Wos 000283939200013 Publication Date 2010-10-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-6520;2041-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.668 Times cited 12 Open Access  
  Notes Approved Most recent IF: 8.668; 2010 IF: NA  
  Call Number UA @ lucian @ c:irua:85823 Serial 3517  
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Author Verbeeck, J.; Van Aert, S.; Zhang, L.; Haiyan, T.; Schattschneider, P.; Rosenauer, A. url  doi
openurl 
  Title Computational aspects in quantitative EELS Type A1 Journal article
  Year 2010 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 16 Issue S:2 Pages 240-241  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Cambridge, Mass. Editor  
  Language Wos Publication Date 2010-08-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record  
  Impact Factor 1.891 Times cited Open Access  
  Notes Approved Most recent IF: 1.891; 2010 IF: 3.259  
  Call Number UA @ lucian @ c:irua:96556UA @ admin @ c:irua:96556 Serial 454  
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Author Ke, X.; Bals, S.; Cott, D.; Hantschel, T.; Bender, H.; Van Tendeloo, G. doi  openurl
  Title Three-dimensional analysis of carbon nanotube networks in interconnects by electron tomography without missing wedge artifacts Type A1 Journal article
  Year 2010 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 16 Issue 2 Pages 210-217  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The three-dimensional (3D) distribution of carbon nanotubes (CNTs) grown inside semiconductor contact holes is studied by electron tomography. The use of a specialized tomography holder results in an angular tilt range of ±90°, which means that the so-called missing wedge is absent. The transmission electron microscopy (TEM) sample for this purpose consists of a micropillar that is prepared by a dedicated procedure using the focused ion beam (FIB) but keeping the CNTs intact. The 3D results are combined with energy dispersive X-ray spectroscopy (EDS) to study the relation between the CNTs and the catalyst particles used during their growth. The reconstruction, based on the full range of tilt angles, is compared with a reconstruction where a missing wedge is present. This clearly illustates that the missing wedge will lead to an unreliable interpretation and will limit quantitative studies  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Cambridge, Mass. Editor  
  Language Wos 000276137200011 Publication Date 2010-02-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.891 Times cited 42 Open Access  
  Notes Esteem 026019; Fwo; Iap-Vi Approved Most recent IF: 1.891; 2010 IF: 3.259  
  Call Number UA @ lucian @ c:irua:82279 Serial 3642  
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Author Zelaya, E.; Schryvers, D.; Tolley, A.; Fitchner, P.F.P. pdf  doi
openurl 
  Title Cavity nucleation and growth in Cu-Zn-Al irradiated with Cu+ ions at different temperatures Type A1 Journal article
  Year 2010 Publication Intermetallics Abbreviated Journal Intermetallics  
  Volume 18 Issue 4 Pages 493-498  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The effects of high dose ion irradiation in β CuZnAl were investigated between room temperature and 150 °C. Single crystal samples with surface normal close to [001]β were irradiated with 300 keV Cu+ ions. Microstructural changes were characterized using transmission electron microscopy. Irradiation induced cavities located on the surface exposed to the irradiation were observed. The morphology, size and density distribution of these cavities were analyzed as a function of different irradiation conditions. The shape and location of the cavities with respect to the irradiation surface were not affected by irradiation temperature or irradiation dose. Instead, the cavity size distribution showed a bi-modal shape for a dose of 15 dpa, regardless of irradiation temperature. For a dose of 30 dpa the bi-modal distribution was only observed after room temperature irradiation. The diffusion effects of vacancies produced by irradiation are analyzed in shape memory CuZnAl alloys, which main characteristic is the diffusionless martensitic transformation. Particularly, the cavity size distributions were analyzed in terms of nucleation, growth and coalescence.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Chicago, Ill. Editor  
  Language Wos 000276058200014 Publication Date 2009-10-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0966-9795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.14 Times cited 1 Open Access  
  Notes Iaea Approved Most recent IF: 3.14; 2010 IF: 2.335  
  Call Number UA @ lucian @ c:irua:80924 Serial 302  
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Author Delville, R.; Schryvers, D. pdf  doi
openurl 
  Title Transmission electron microscopy study of combined precipitation of Ti2Ni(Pd) and Ti2Pd(Ni) in a Ti50Ni30Pd20 alloy Type A1 Journal article
  Year 2010 Publication Intermetallics Abbreviated Journal Intermetallics  
  Volume 18 Issue 12 Pages 2353-2360  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We report a new mode of precipitation in a B19 martensitic Ti50Ni30Pd20 shape memory alloy consisting of a central Ti2Ni(Pd) precipitate surrounded by an austenite area containing Ti2Pd(Ni) precipitates. The morphology and crystallography of the precipitation area is investigated using conventional and high resolution electron microscopy. In particular, the orientation relationship and the coherency strain between the Ti2Pd(Ni) precipitate and the surrounding retained B2 matrix are discussed. A study of local composition in relation with a ternary phase diagram using X-ray energy dispersive spectroscopy with a nanoprobe gives evidences of the formation mechanism.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Chicago, Ill. Editor  
  Language Wos 000284447500014 Publication Date 2010-09-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0966-9795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.14 Times cited 9 Open Access  
  Notes Multimat; Iap Approved Most recent IF: 3.14; 2010 IF: 2.335  
  Call Number UA @ lucian @ c:irua:84473 Serial 3714  
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Author Gorlé, C.; van Beeck, J.; Rambaud, P. url  doi
openurl 
  Title Dispersion in the wake of a rectangular building : validation of two Reynolds-averaged Navier-Stokes modelling approaches Type A1 Journal article
  Year 2010 Publication Boundary-layer meteorology Abbreviated Journal Bound-Lay Meteorol  
  Volume 137 Issue 1 Pages 115-133  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract When modelling the turbulent dispersion of a passive tracer using Reynolds-averaged Navier-Stokes (RANS) simulations, two different approaches can be used. The first consists of solving a transport equation for a scalar, where the governing parameters are the mean velocity field and the turbulent diffusion coefficient, given by the ratio of the turbulent viscosity and the turbulent Schmidt number Sc (t) . The second approach uses a Lagrangian particle tracking algorithm, where the governing parameters are the mean velocity and the fluctuating velocity field, which is determined from the turbulence kinetic energy and the Lagrangian time T (L) . A comparison between the two approaches and wind-tunnel data for the dispersion in the wake of a rectangular building immersed in a neutral atmospheric boundary layer (ABL) is presented. Particular attention was paid to the influence of turbulence model parameters on the flow and concentration field. In addition, an approach to estimate Sc (t) and T (L) based on the calculated flow field is proposed. The results show that applying modified turbulence model constants to enable correct modelling of the ABL improves the prediction for the velocity and concentration fields when the modification is restricted to the region for which it was derived. The difference between simulated and measured concentrations is smaller than 25% or the uncertainty of the data on 76% of the points when solving the transport equation for a scalar with the proposed formulation for Sc (t) , and on 69% of the points when using the Lagrangian particle tracking with the proposed formulation for T (L) .  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Dordrecht Editor  
  Language Wos 000281712500006 Publication Date 2010-06-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0006-8314;1573-1472; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.573 Times cited 16 Open Access  
  Notes Approved Most recent IF: 2.573; 2010 IF: 1.879  
  Call Number UA @ lucian @ c:irua:95570 Serial 736  
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Author Amin-Ahmadi, B.; Aashuri, H. doi  openurl
  Title Globular structure of M2 high speed steel by thermomechanical treatment in the semisolid state Type A1 Journal article
  Year 2010 Publication Steel research international Abbreviated Journal Steel Res Int  
  Volume 81 Issue 5 Pages 381-386  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The globular structure of M2 high speed steel in the rolled – annealed and as cast conditions was investigated in the semisolid state. Metallographic observations resulted in globular austenite particles that were surrounded by a liquid phase. Dissolution of various carbides in the austenite phase at semisolid temperatures led to grain boundary liquation and formation of near-spherical solid grains in a liquid matrix. Therefore, at the semisolid state, the solid particles were free from carbides. MC- type and M6C- type eutectic carbides re- precipitated at the grain boundaries during cooling of the samples from the semisolid temperature. The variation of shape factor versus holding time and holding temperature was examined. A transition value for shape factor changes in high speed steels was achieved. The growth rate constants of the Ostwald ripening and the coalescence mechanisms were calculated by using the experimentally determined rate constant. It was observed that less liquid droplets were enclosed inside the solid particles compared with non-ferrous alloys. Besides, it has been shown that at high solid fraction, the Ostwald ripening mechanism plays a prominent role in the coarsening phenomenon in comparison with the coalescence mechanism. Grains can rotate and arrange low misorientation with each other at high liquid contents, therefore low energetic grain boundaries form between these grains. These grain boundaries play an important role in the coalescence mechanism.  
  Address  
  Corporate Author Thesis  
  Publisher Verlag Stahleisen Place of Publication (up) Düsseldorf Editor  
  Language Wos 000278292200007 Publication Date 2010-05-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1611-3683;1869-344X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.235 Times cited 1 Open Access  
  Notes Approved Most recent IF: 1.235; 2010 IF: 0.455  
  Call Number UA @ lucian @ c:irua:122047 Serial 1347  
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Author King, G.; Abakumov, A.M.; Hadermann, J.; Alekseeva, A.M.; Rozova, M.G.; Perkisas, T.; Woodward, P.M.; Van Tendeloo, G.; Antipov, E.V. doi  openurl
  Title Crystal structure and phase transitions in Sr3WO6 Type A1 Journal article
  Year 2010 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 49 Issue 13 Pages 6058-6065  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The crystal structures of the beta and gamma polymorphs of Sr3WO6 and the gamma <->beta phase transition have been investigated using electron diffraction, synchrotron X-ray powder diffraction, and neutron powder diffraction. The gamma-Sr3WO6 polymorph is stable above T-c approximate to 470 K and adopts a monoclinically distorted double perovskite A(2)BB'O-6= Sr2SrWO6 structure (space group Cc, a = 10.2363(1)angstrom, b= 17.9007(1)angstrom, c= 11.9717(1)angstrom, beta=125.585(1)degrees at T= 1373 K, Z=12, corresponding to a = a(p)+1/2b(p) – 1/2c(p), b =3/2b(p) + 3/2c(p), c =-b(p) + c(p), a(p),b(p), c(p), lattice vectors of the parent Fm (3) over barm double perovskite structure). Upon cooling it undergoes a continuous phase transition into the triclinically distorted beta-Sr3WO6 phase (space group Cl, a = 10.09497(3)angstrom, b = 17.64748(5)angstrom, c = 11.81400(3)angstrom, alpha = 89.5470(2)degrees, beta= 125.4529(2)degrees, gamma =90.2889(2)degrees at T= 300 K). Both crystal structures of Sr3WO6 belong to a family of double perovskites with broken corner sharing connectivity of the octahedral framework. A remarkable feature of the gamma-Sr3WO6 structure is a non-cooperative rotation of the WO6 octahedra. One third of the WO6 octahedra are rotated by 45 about either the bp or the cp axis of the parent double perovskite structure. As a result, the WO6 octahedra do not share corners but instead share edges with the coordination polyhedra of the Sr cations at the B positions increasing their coordination number from 6 to 7 or 8. The crystal structure of the beta-phase is very close to the structure of the gamma-phase; decreasing symmetry upon the gamma ->beta transformation occurs because of unequal octahedral rotation angles about the bp and cp axes and increasing distortions of the WO6 octahedra.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Easton, Pa Editor  
  Language Wos 000279211500036 Publication Date 2010-06-09  
  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 18 Open Access  
  Notes Approved Most recent IF: 4.857; 2010 IF: 4.326  
  Call Number UA @ lucian @ c:irua:83877 Serial 562  
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Author Panin, R.V.; Khasanova, N.R.; Bougerol, C.; Schnelle, W.; Van Tendeloo, G.; Antipov, E.V. pdf  doi
openurl 
  Title Ordering of Pd2+ and Pd4+ in the mixed-valent palladate KPd2O3 Type A1 Journal article
  Year 2010 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 49 Issue 4 Pages 1295-1297  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A new potassium palladate KPd2O3 was synthesized by the reaction of KO2 and PdO at elevated oxygen pressure. Its crystal structure was solved from powder X-ray diffraction data in the space group Rm (a = 6.0730(1) Å, c = 18.7770(7) Å, and Z = 6). KPd2O3 represents a new structure type, consisting of an alternating sequence of K+ and Pd2O3− layers with ordered Pd2+ and Pd4+ ions. The presence of palladium ions in di- and tetravalent low-spin states was confirmed by magnetic susceptibility measurements.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Easton, Pa Editor  
  Language Wos 000274240700009 Publication Date 2010-01-12  
  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 9 Open Access  
  Notes Iap Iv Approved Most recent IF: 4.857; 2010 IF: 4.326  
  Call Number UA @ lucian @ c:irua:80990 Serial 2507  
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Author Abakumov, A.M.; Hadermann, J.; Batuk, M.; d' Hondt, H.; Tyablikov, O.A.; Rozova, M.G.; Pokholok, K.V.; Filimonov, D.S.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V. pdf  doi
openurl 
  Title Slicing the Perovskite structure with crystallographic shear planes : the AnBnO3n-2 homologous series Type A1 Journal article
  Year 2010 Publication Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 49 Issue 20 Pages 9508-9516  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract A new AnBnO3n−2 homologous series of anion-deficient perovskites has been evidenced by preparation of the members with n = 5 (Pb2.9Ba2.1Fe4TiO13) and n = 6 (Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16) in a single phase form. The crystal structures of these compounds were determined using a combination of transmission electron microscopy and X-ray and neutron powder diffraction (S.G. Ammm, a = 5.74313(7), b = 3.98402(4), c = 26.8378(4) Å, RI = 0.035, RP = 0.042 for Pb2.9Ba2.1Fe4TiO13 and S.G. Imma, a = 5.7199(1), b = 3.97066(7), c = 32.5245(8) Å, RI = 0.032, RP = 0.037 for Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16). The crystal structures of the AnBnO3n−2 homologues are formed by slicing the perovskite structure with (01)p crystallographic shear (CS) planes. The shear planes remove a layer of oxygen atoms and displace the perovskite blocks with respect to each other by the 1/2[110]p vector. The CS planes introduce edge-sharing connections of the transition metal−oxygen polyhedra at the interface between the perovskite blocks. This results in intrinsically frustrated magnetic couplings between the perovskite blocks due to a competition of the exchange interactions between the edge- and the corner-sharing metal−oxygen polyhedra. Despite the magnetic frustration, neutron powder diffraction and Mssbauer spectroscopy reveal that Pb2.9Ba2.1Fe4TiO13 and Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16 are antiferromagnetically ordered below TN = 407 and 343 K, respectively. The Pb2.9Ba2.1Fe4TiO13 and Pb3.8Bi0.2Ba2Fe4.2Ti1.8O16 compounds are in a paraelectric state in the 5−300 K temperature range.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Easton, Pa Editor  
  Language Wos 000282783400051 Publication Date 2010-09-24  
  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 23 Open Access  
  Notes Esteem 026019; Fwo Approved Most recent IF: 4.857; 2010 IF: 4.326  
  Call Number UA @ lucian @ c:irua:84963 Serial 3041  
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Author de Backer, J.W.; Vos, W.G.; Vinchurkar, S.C.; Claes, R.; Drollmann, A.; Wulfrank, D.; Parizel, P.M.; Germonpré, P.; de Backer, W. pdf  doi
openurl 
  Title Validation of computational fluid dynamics in CT-based airway models with SPECT/CT1 Type A1 Journal article
  Year 2010 Publication Radiology Abbreviated Journal Radiology  
  Volume 257 Issue 3 Pages 854-862  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract Purpose: To compare the results obtained by using numerical flow simulations with the results of combined single photon emission computed tomography (SPECT) and computed tomography (CT) and to demonstrate the importance of correct boundary conditions for the numerical methods to account for the large amount of interpatient variability in airway geometry. Materials and Methods: This study was approved by all relevant institutional review boards. All patients gave their signed informed consent. In this study, six patients with mild asthma (three men; three women; overall mean age, 46 years ± 17 [standard deviation]) underwent CT at functional residual capacity and total lung capacity, as well as SPECT/CT. CT data were used for segmentation and computational fluid dynamics (CFD) simulations. A comparison was made between airflow distribution, as derived with (a) SPECT/CT through tracer concentration analysis, (b) CT through lobar expansion measurement, and (c) CFD through flow computer simulation. Also, the heterogeneity of the ventilation was examined. Results: Good agreement was found between SPECT/CT, CT, and CFD in terms of airflow distribution and hot spot detection. The average difference for the internal airflow distribution was less than 3% for CFD and CT versus SPECT/CT. Heterogeneity in ventilation patterns could be detected with SPECT/CT and CFD. Conclusion: This results of this study show that patient-specific computer simulations with appropriate boundary conditions yield information that is similar to that obtained with functional imaging tools, such as SPECT/CT.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Easton, Pa Editor  
  Language Wos 000284469300031 Publication Date 2010-11-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0033-8419;1527-1315; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 7.296 Times cited 100 Open Access  
  Notes ; Supported by Novartis. ; Approved Most recent IF: 7.296; 2010 IF: 6.069  
  Call Number UA @ lucian @ c:irua:85379 Serial 3831  
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Author Piacente, G.; Hai, G.Q.; Peeters, F.M. url  doi
openurl 
  Title Continuous structural transitions in quasi-one-dimensional classical Wigner crystals Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 2 Pages  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study the structural phase transitions in confined systems of strongly interacting particles. We consider infinite quasi-one-dimensional systems with different pairwise repulsive interactions in the presence of an external confinement following a power law. Within the framework of Landaus theory, we find the necessary conditions to observe continuous transitions and demonstrate that the only allowed continuous transition is between the single- and the double-chain configurations and that it only takes place when the confinement is parabolic. We determine analytically the behavior of the system at the transition point and calculate the critical exponents. Furthermore, we perform Monte Carlo simulations and find a perfect agreement between theory and numerics.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lancaster, Pa Editor  
  Language Wos 000274002100035 Publication Date 2010-01-19  
  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 37 Open Access  
  Notes ; The authors acknowledge FAPESP and CNPq (Brazil), the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl) (Belgium) for financial support. ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:81243 Serial 493  
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Author Tkachenko, D.V.; Misko, V.R.; Peeters, F.M. doi  openurl
  Title Effect of correlated noise on quasi-one-dimensional diffusion Type A1 Journal article
  Year 2010 Publication Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E  
  Volume 82 Issue 5 Pages 051102-051102,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Single-file diffusion (SFD) of an infinite one-dimensional chain of interacting particles has a long-time mean-square displacement ∝t1/2, independent of the type of interparticle repulsive interaction. This behavior is also observed in finite-size chains, although only for certain intervals of time t depending on the chain length L, followed by the ∝t for t→∞, as we demonstrate for a closed circular chain of diffusing interacting particles. Here, we show that spatial correlation of noise slows down SFD and can result, depending on the amount of correlated noise, in either subdiffusive behavior ∝tα, where 0<α<1/2, or even in a total suppression of diffusion (in the limit N→∞). Spatial correlation can explain the subdiffusive behavior in recent SFD experiments in circular channels.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lancaster, Pa Editor  
  Language Wos 000283710100001 Publication Date 2010-11-02  
  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 ; We acknowledge discussions with M. Saint-Jean. This work was supported by the “Odysseus” program of the Flemish Government and the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 2.366; 2010 IF: 2.352  
  Call Number UA @ lucian @ c:irua:85799 Serial 806  
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Author Chen, Y.; Shanenko, A.A.; Peeters, F.M. url  doi
openurl 
  Title Hollow nanocylinder: multisubband superconductivity induced by quantum confinement Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 13 Pages 134523-134523:11  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Quantization of the transverse electron motion in high-quality superconducting metallic nanowires and nanofilms results in the formation of well-distinguished single-electron subbands. They shift in energy with changing thickness, which is known to cause quantum-size superconducting oscillations. The formation of multiple subbands results in a multigap structure induced by the interplay between quantum confinement and Andreev mechanism. We investigate multisubband superconductivity in a hollow nanocylinder by numerically solving the Bogoliubov-de Gennes equations. When changing the inner radius and thickness of the hollow nanocylinder, we find a crossover from an irregular pattern of quantum-size superconducting oscillations, typical of nanowires, to an almost regular regime, specific for superconducting nanofilms. At this crossover the multigap structure becomes degenerate. The ratio of the critical temperature to the energy gap increases and approaches its bulk value while being reduced by 20-30% due to Andreev-type states driven by quantum confinement in the irregular regime.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lancaster, Pa Editor  
  Language Wos 000277207900098 Publication Date 2010-04-26  
  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 ; This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles Programme, Belgian States, Belgian Science Policy (IAP) and the ESF-AQDJJ network. ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:95623 Serial 1481  
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Author Pogosov, W.V.; Zhao, H.J.; Misko, V.R.; Peeters, F.M. url  doi
openurl 
  Title Kink-antikink vortex transfer in periodic-plus-random pinning potential : theoretical analysis and numerical experiments Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 2 Pages  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The influence of random pinning on the vortex dynamics in a periodic square potential under an external drive is investigated. Using numerical experiments and theoretical approach, we found several dynamical regimes of vortex motion that are different from the ones for a regular pinning potential. Vortex transfer is controlled by kinks and antikinks, which either pre-exist in the system or appear spontaneously in pairs and then propagate. When kinks and antikinks collide, they annihilate. We provide clear physical interpretations of the observed features.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lancaster, Pa Editor  
  Language Wos 000274002100087 Publication Date 2010-01-19  
  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 10 Open Access  
  Notes ; This work was supported by the “Odysseus” Program of the Flemish government, FWO-Vl, and IAP. W.V.P. acknowledges support from RFBR (Contract No. 09-02-00248). ; Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:81251 Serial 1761  
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Author Zhang, L.; Turner, S.; Brosens, F.; Verbeeck, J. url  doi
openurl 
  Title Model-based determination of dielectric function by STEM low-loss EELS Type A1 Journal article
  Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 81 Issue 3 Pages 035102  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Theory of quantum systems and complex systems  
  Abstract Dielectric properties of materials are crucial in describing the electromagnetic response of materials. As devices are becoming considerably smaller than the optical wavelength, the conventional measuring methods based on optical response are limited by their spatial resolution. Electron energy loss spectroscopy performed in a scanning transmission electron microscope is a good alternative to obtain the dielectric properties with excellent spatial resolution. Due to the overlap of diffraction discs in scanning transmission electron microscopy, it is difficult to apply conventional experimental settings to suppress retardation losses. In this contribution, a relativistic dielectric model for the loss function is presented which is used in a model based optimization scheme to estimate the complex dielectric function of a material. The method is applied to experiments on bulk diamond and SrTiO3 and shows a good agreement with optical reference data when retardation effects are included. Application of this technique to nanoparticles is possible but several theoretical assumptions made in the model of the loss function are violated and interpretation becomes problematic.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lancaster, Pa Editor  
  Language Wos 000274002300027 Publication Date 2010-01-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 9 Open Access  
  Notes Esteem – 026019; Fwo Approved Most recent IF: 3.836; 2010 IF: 3.774  
  Call Number UA @ lucian @ c:irua:81258UA @ admin @ c:irua:81258 Serial 2098  
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Author Khalil-Allafi, J.; Amin-Ahmadi, B.; Zare, M. pdf  doi
openurl 
  Title Biocompatibility and corrosion behavior of the shape memory NiTi alloy in the physiological environments simulated with body fluids for medical applications Type A1 Journal article
  Year 2010 Publication Materials science and engineering: part C: biomimetic materials Abbreviated Journal Mat Sci Eng C-Mater  
  Volume 30 Issue 8 Pages 1112-1117  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Due to unique properties of NiTi shape memory alloys such as high corrosion resistance, biocompatibility, super elasticity and shape memory behavior, NiTi shape memory alloys are suitable materials for medical applications. Although TiO2 passive layer in these alloys can prevent releasing of nickel to the environment, high nickel content and stability of passive layer in these alloys are very debatable subjects. In this study a NiTi shape memory alloy with nominal composition of 50.7 atom% Ni was investigated by corrosion tests. Electrochemical tests were performed in two physiological environments of Ringer solution and NaCl 0.9% solution. Results indicate that the breakdown potential of the NiTi alloy in NaCl 0.9% solution is higher than that in Ringer solution. The results of Scanning Electron Microscope (SEM) reveal that low pitting corrosion occurred in Ringer solution compared with NaCl solution at potentiostatic tests. The pH value of the solutions increases after the electrochemical tests. The existence of hydride products in the X-ray diffraction analysis confirms the decrease of the concentration of hydrogen ion in solutions. Topographical evaluations show that corrosion products are nearly same in all samples. The biocompatibility tests were performed by reaction of mouse fibroblast cells (L929). The growth and development of cells for different times were measured by numbering the cells or statistics investigations. The figures of cells for different times showed natural growth of cells. The different of the cell numbers between the test specimen and control specimen was negligible; therefore it may be concluded that the NiTi shape memory alloy is not toxic in the physiological environments simulated with body fluids.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lausanne Editor  
  Language Wos 000282905600006 Publication Date 2010-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0928-4931; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.164 Times cited 34 Open Access  
  Notes Approved Most recent IF: 4.164; 2010 IF: 2.180  
  Call Number UA @ lucian @ c:irua:122039 Serial 242  
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Author Tirry, W.; Coghe, F.; Bouvier, S.; Gasperini, M.; Rabet, L.; Schryvers, D. pdf  doi
openurl 
  Title A multi-scale characterization of deformation twins in Ti6Al4V sheet material deformed by simple shear Type A1 Journal article
  Year 2010 Publication Materials science and engineering: part A: structural materials: properties, microstructure and processing Abbreviated Journal Mat Sci Eng A-Struct  
  Volume 527 Issue 16/17 Pages 4136-4145  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Ti6Al4V sheet material is subjected to simple shear deformation with strain ratio's of 10%, 30% and 50%. Optical microscopy, transmission electron microscopy and electron backscatter diffraction techniques are applied to study the presence and morphology of deformation twins. Only the View the MathML source type of twins seems to be present with a volume fraction below 1%. These View the MathML source twins show a high density of basal stacking faults of the ABABACAC type identified using atomic resolution transmission electron microscopy. A resolved shear stress analysis shows that twins most often occur on those planes with the highest resolved shear stresses, but that the starting texture is not beneficial for the occurrence of twins. It is further suggested that a transitory strain hardening regime observed around 530 MPa might be related with the onset of twinning.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lausanne Editor  
  Language Wos 000278766800068 Publication Date 2010-03-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0921-5093; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.094 Times cited 20 Open Access  
  Notes Iap Approved Most recent IF: 3.094; 2010 IF: 2.101  
  Call Number UA @ lucian @ c:irua:82291 Serial 2212  
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Author Lorenz, H.; Zhao, Q.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Klötzer, B.; Rameshan, C.; Penner, S. pdf  doi
openurl 
  Title Preparation and structural characterization of SnO2 and GeO2 methanol steam reforming thin film model catalysts by (HR)TEM Type A1 Journal article
  Year 2010 Publication Materials chemistry and physics Abbreviated Journal Mater Chem Phys  
  Volume 122 Issue 2/3 Pages 623-629  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Structure, morphology and composition of different tin oxide and germanium oxide thin film catalysts for the methanol steam reforming (MSR) reaction have been studied by a combination of (high-resolution) transmission electron microscopy, selected area electron diffraction, dark-field imaging and electron energy-loss spectroscopy. Deposition of the thin films on NaCl(0 0 1) cleavage faces has been carried out by thermal evaporation of the respective SnO2 and GeO2 powders in varying oxygen partial pressures and at different substrate temperatures. Preparation of tin oxide films in high oxygen pressures (10−1 Pa) exclusively resulted in SnO phases, at and above 473 K substrate temperature epitaxial growth of SnO on NaCl(0 0 1) leads to well-ordered films. For lower oxygen partial pressures (10−3 to 10−2 Pa), mixtures of SnO and β-Sn are obtained. Well-ordered SnO2 films, as verified by electron diffraction patterns and energy-loss spectra, are only obtained after post-oxidation of SnO films at temperatures T ≥ 673 K in 105 Pa O2. Preparation of GeOx films inevitably results in amorphous films with a composition close to GeO2, which cannot be crystallized by annealing treatments in oxygen or hydrogen at temperatures comparable to SnO/SnO2. Similarities and differences to neighbouring oxides relevant for selective MSR in the third group of the periodic system (In2O3 and Ga2O3) are also discussed with the aim of cross-correlation in formation of nanomaterials, and ultimately, also catalytic properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) Lausanne Editor  
  Language Wos 000278637900054 Publication Date 2010-04-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0254-0584; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.084 Times cited 15 Open Access  
  Notes Esteem 026019 Approved Most recent IF: 2.084; 2010 IF: 2.356  
  Call Number UA @ lucian @ c:irua:83099 Serial 2699  
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Author Yang, T.; Perkisas, T.; Hadermann, J.; Croft, M.; Ignatov, A.; Greenblatt, M. pdf  doi
openurl 
  Title B-site ordered perovskite LaSrMnNbO6 : synthesis, structure and antiferromagnetism Type A1 Journal article
  Year 2010 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 183 Issue 11 Pages 2689-2694  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract LaSrMnNbO6 has been synthesized by high temperature solid state reaction under 1% H2/Ar dynamic flow. The structure is determined by Rietveld refinement of the powder X-ray diffraction data. It crystallizes in the monoclinic space group P21/n with the unit cell parameters: a=5.69187(12), b=5.74732(10), c=8.07018(15) Å and β=90.0504(29)°, which were also confirmed by electron diffraction. The Mn2+ and Nb5+ ions, whose valence states are confirmed by X-ray absorption near-edge spectroscopy, are almost completely ordered over the B-site (<1% inversion) of the perovskite structure due to the large differences of both cationic size (0.19 Å) and charge. The octahedral framework displays significant tilting distortion according to Glazers tilt system a−b−c+. Upon heating, LaSrMnNbO6 decomposes at 690 °C under O2 flow or at 775 °C in air. The magnetic susceptibility data indicate the presence of long-range antiferromagnetic ordering at TN=8 K; the experimentally observed effective paramagnetic moment, μeff=5.76 μB for high spin Mn2+ (3d5, S=5/2) is in good agreement with the calculated value (μcalcd=5.92 μB).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000284179800028 Publication Date 2010-09-13  
  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 13 Open Access  
  Notes Esteem 026019 Approved Most recent IF: 2.299; 2010 IF: 2.261  
  Call Number UA @ lucian @ c:irua:85805 Serial 212  
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Author Abakumov, A.M.; d' Hondt, H.; Rossell, M.D.; Tsirlin, A.A.; Gutnikova, O.; Filimonov, D.S.; Schnelle, W.; Rosner, H.; Hadermann, J.; Van Tendeloo, G.; Antipov, E.V. doi  openurl
  Title Coupled anion and cation ordering in Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficientperovskites Type A1 Journal article
  Year 2010 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 183 Issue 12 Pages 2845-2854  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The Sr3RFe4O10.5 (R=Y, Ho, Dy) anion-deficient perovskites were prepared using a solid-state reaction in evacuated sealed silica tubes. Transmission electron microscopy and 57Fe Mössbauer spectroscopy evidenced a complete A-cations and oxygen vacancies ordering. The structure model was further refined by ab initio structure relaxation, based on density functional theory calculations. The compounds crystallize in a tetragonal a≈2√2ap≈11.3 Å, с≈4сp≈16 Å unit cell (ap: parameter of the perovskite subcell) with the P42/mnm space group. Oxygen vacancies reside in the (FeO5/4□3/4) layers, comprising corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids, which are sandwiched between the layers of the FeO6 octahedra. Smaller R atoms occupy the 9-fold coordinated position, whereas the 10-fold coordinated positions are occupied by larger Sr atoms. The Fe sublattice is ordered aniferromagnetically up to at least 500 K, while the rare-earth sublattice remains disordered down to 2 K.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000285431100014 Publication Date 2010-10-02  
  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 8 Open Access  
  Notes Approved Most recent IF: 2.299; 2010 IF: 2.261  
  Call Number UA @ lucian @ c:irua:88071 Serial 533  
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Author Čukarić, N.; Tadić, M.; Peeters, F.M. doi  openurl
  Title Electron and hole states in a quantum ring grown by droplet epitaxy. Influence of the layer inside the ring opening Type A1 Journal article
  Year 2010 Publication Superlattices and microstructures Abbreviated Journal Superlattice Microst  
  Volume 48 Issue 5 Pages 491-501  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic structure of the conduction and valence bands of a quantum ring containing a layer inside the ring opening is modeled This structure (nanocup) consists of a GaAs nanodisk (the cup s bottom) and a GaAs nanoring (the cup s rim) which encircles the disk The whole system is embedded in an (Al Ga)As matrix and its shape resembles realistic ring structures grown by the droplet epitaxy technique The conduction-band states in the structure are modeled by the single-band effective-mass theory while the 4-band Luttinger-Kohn model is adopted to compute the valence-band states We analyze how the electronic structure of the nanocup evolves from the one of a quantum ring when the size of either the nanodisk or the nanoring is changed For that purpose (1) the width of the ring (2) the disk radius and (3) the disk height are separately varied For dimensions typical for experimentally realized structures we find that the electron wavefunctions are mainly localized inside the ring even when the thickness of the Inner layer is 90% of the ring thickness These calculations indicate that topological phenomena like the excitonic Aharonov-Bohm effect are negligibly affected by the presence of the layer inside the ring (C) 2010 Elsevier Ltd All rights reserved  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000284521400005 Publication Date 2010-09-22  
  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 2.123 Times cited 9 Open Access  
  Notes ; The authors would like to thank Prof B Partoens for useful discussions This work was supported by the EU NoE SANDiE the Ministry of Science of Serbia the Flemish Science Foundation (FWO-VI) and the Belgian Science Policy (IAP) ; Approved Most recent IF: 2.123; 2010 IF: 1.096  
  Call Number UA @ lucian @ c:irua:95551 Serial 906  
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Author Mao, M.; Bogaerts, A. doi  openurl
  Title Investigating the plasma chemistry for the synthesis of carbon nanotubes/nanofibres in an inductively coupled plasma enhanced CVD system : the effect of different gas mixtures Type A1 Journal article
  Year 2010 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys  
  Volume 43 Issue 20 Pages 205201,1-205201,20  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract A hybrid model, called the hybrid plasma equipment model (HPEM), was used to study an inductively coupled plasma in gas mixtures of H2 or NH3 with CH4 or C2H2 used for the synthesis of carbon nanotubes or carbon nanofibres (CNTs/CNFs). The plasma properties are discussed for different gas mixtures at low and moderate pressures, and the growth precursors for CNTs/CNFs are analysed. It is found that C2H2, C2H4 and C2H6 are the predominant molecules in CH4 containing plasmas besides the feedstock gas, and serve as carbon sources for CNT/CNF formation. On the other hand, long-chain hydrocarbons are observed in C2H2-containing plasmas. Furthermore, the background gases CH4 and C2H2 show a different decomposition rate with H2 or NH3 addition at moderate pressures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000277373400009 Publication Date 2010-05-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.588 Times cited 52 Open Access  
  Notes Approved Most recent IF: 2.588; 2010 IF: 2.109  
  Call Number UA @ lucian @ c:irua:82067 Serial 1723  
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Author Mao, M.; Bogaerts, A. doi  openurl
  Title Investigating the plasma chemistry for the synthesis of carbon nanotubes/nanofibres in an inductively coupled plasma-enhanced CVD system : the effect of processing parameters Type A1 Journal article
  Year 2010 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys  
  Volume 43 Issue 31 Pages 315203-315203,15  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract A parameter study is carried out for an inductively coupled plasma used for the synthesis of carbon nanotubes or carbon nanofibres (CNTs/CNFs), by means of the Hybrid Plasma Equipment Model. The influence of processing parameters including gas ratio for four different gas mixtures typically used for CNT/CNF growth (i.e. CH4/H2, CH4/NH3, C2H2/H2 and C2H2/NH3), inductively coupled plasma (ICP) power (501000 W), operating pressure (10 mTorr1 Torr), bias power (01000 W) and temperature of the substrate (01000 °C) on the plasma chemistry is investigated and the optimized conditions for CNT/CNF growth are analysed. Summarized, our calculations suggest that a lower fraction of hydrocarbon gases (CH4 or C2H2, i.e. below 20%) and hence a higher fraction of etchant gases (H2 or NH3) in the gas mixture result in more 'clean' conditions for controlled CNT/CNF growth. The same applies to a higher ICP power, a moderate ICP gas pressure above 100 mTorr (at least for single-walled carbon nanotubes), a high bias power (for aligned CNTs) and an intermediate substrate temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000280275200007 Publication Date 2010-07-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.588 Times cited 17 Open Access  
  Notes Approved Most recent IF: 2.588; 2010 IF: 2.109  
  Call Number UA @ lucian @ c:irua:88365 Serial 1724  
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Author Pereira, J.M.; Peeters, F.M.; Chaves, A.; Farias, G.A. pdf  doi
openurl 
  Title Klein tunneling in single and multiple barriers in graphene Type A1 Journal article
  Year 2010 Publication Semiconductor science and technology Abbreviated Journal Semicond Sci Tech  
  Volume 25 Issue 3 Pages 033002,1-033002,9  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We review the transmission properties of carriers interacting with potential barriers in graphene. The tunneling of electrons and holes in quantum structures in graphene is found to display features that are in marked contrast with those of other systems. In particular, the interaction between the carriers with electrostatic potential barriers can be related to the propagation of electromagnetic waves in media with negative refraction indices, also known as metamaterials. This behavior becomes evident as one calculates the time evolution of wavepackets propagating across the barrier interface. In addition, we discuss the effect of trigonal warping on the tunneling through potential barriers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000274318300004 Publication Date 2010-02-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0268-1242;1361-6641; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.305 Times cited 83 Open Access  
  Notes ; We want to acknowledge our collaborators in this work: P Vasilopoulos and M Barbier. This work was supported by the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved Most recent IF: 2.305; 2010 IF: 1.333  
  Call Number UA @ lucian @ c:irua:80961 Serial 1764  
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Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. pdf  doi
openurl 
  Title Kronig-Penney model of scalar and vector potentials in graphene Type A1 Journal article
  Year 2010 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 22 Issue 46 Pages 465302,1-465302,10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We consider a one-dimensional (1D) superlattice (SL) on graphene consisting of very high and very thin (δ-function) magnetic and potential barriers with zero average potential and zero magnetic field. We calculate the energy spectrum analytically, study it in different limiting cases, and determine the condition under which an electron beam incident on an SL is highly collimated along its direction. In the absence of the magnetic SL the collimation is very sensitive to the value of W/Ws and is optimal for W/Ws = 1, where W is the distance between the positive and negative barriers and L = W + Ws is the size of the unit cell. In the presence of only the magnetic SL the collimation decreases and the symmetry of the spectrum around ky is broken for W/Ws\neq 1 . In addition, a gap opens which depends on the strength of the magnetic field. We also investigate the effect of spatially separated potential and magnetic δ-function barriers and predict a better collimation in specific cases.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000283838800004 Publication Date 2010-11-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 41 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 2.649; 2010 IF: 2.332  
  Call Number UA @ lucian @ c:irua:85807 Serial 1767  
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Author Bezjak, J.; Abakumov, A.M.; Recnik, A.; Krzmanc, M.M.; Jancar, B.; Suvorov, D. doi  openurl
  Title The local structure and composition of Ba4Nb2O9-based oxycarbonates Type A1 Journal article
  Year 2010 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem  
  Volume 183 Issue 8 Pages 1823-1828  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract X-ray powder-diffraction(XRD),high-resolutiontransmissionelectronmicroscopy(HRTEM),electron diffraction(ED),infraredspectroscopy(IR),thermogravimetry(TG)andmassspectroscopy(MS)were performedtoinvestigatethecompositionandthecrystalstructureoftetra-bariumdi-niobate(V) Ba4Nb2O9. TheTG,MSandIRstudiesrevealedthatthecompoundisahydratedoxycarbonate.Assuming that thecarbonatestoichiometricallyreplacesoxygen,thecompositionofthelow-temperature a-modification,obtainedbyslowcoolingfrom1100 1C, correspondstoBa4Nb2O8.8(CO3)0.2 0.1H2O, while thequenchedhigh-temperature g-modificationhastheBa4Nb2O8.42(CO3)0.58 0.38H2O composi- tion. The a-phase hasacompositeincommensuratelymodulatedstructureconsistingoftwomutually interacting[Ba]N and the[(Nb,)O3]N subsystems.Thecompositemodulatedcrystalstructureofthe a-phase canbedescribedwiththelatticeparameters a¼10.2688(1) A˚ , c¼2.82426(8) A˚ , q¼0.66774(2)c* and asuperspacegroup R3m(00g)0s. TheHRTEManalysisdemonstratesthenanoscale twinningofthetrigonaldomainsparalleltothe{100}crystallographicplanes.Thetwinningintroduces a one-dimensionaldisorderintothe[(Nb,)O3]N subsystem,whichresultsinanaverage P62c crystal structureofthe a-phase. Possibleplacesforthecarbonategroupinthestructurearediscussedusinga comparisonwithotherhexagonalperovskite-basedoxycarbonates.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000280620300013 Publication Date 2010-06-14  
  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 10 Open Access  
  Notes Approved Most recent IF: 2.299; 2010 IF: 2.261  
  Call Number UA @ lucian @ c:irua:84046 Serial 1830  
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Author Bogaerts, A.; De Bie, C.; Eckert, M.; Georgieva, V.; Martens, T.; Neyts, E.; Tinck, S. pdf  doi
openurl 
  Title Modeling of the plasma chemistry and plasmasurface interactions in reactive plasmas Type A1 Journal article
  Year 2010 Publication Pure and applied chemistry Abbreviated Journal Pure Appl Chem  
  Volume 82 Issue 6 Pages 1283-1299  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this paper, an overview is given of modeling activities going on in our research group, for describing the plasma chemistry and plasmasurface interactions in reactive plasmas. The plasma chemistry is calculated by a fluid approach or by hybrid Monte Carlo (MC)fluid modeling. An example of both is illustrated in the first part of the paper. The example of fluid modeling is given for a dielectric barrier discharge (DBD) in CH4/O2, to describe the partial oxidation of CH4 into value-added chemicals. The example of hybrid MCfluid modeling concerns an inductively coupled plasma (ICP) etch reactor in Ar/Cl2/O2, including also the description of the etch process. The second part of the paper deals with the treatment of plasmasurface interactions on the atomic level, with molecular dynamics (MD) simulations or a combination of MD and MC simulations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication (up) London Editor  
  Language Wos 000279063900010 Publication Date 2010-04-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1365-3075;0033-4545; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.626 Times cited 13 Open Access  
  Notes Approved Most recent IF: 2.626; 2010 IF: 2.134  
  Call Number UA @ lucian @ c:irua:82108 Serial 2134  
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