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Author Bittencourt, C.; Krüger, P.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Ewels, C.; Umek, P.; Guttmann, P.
Title Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations Type A1 Journal article
Year 2012 Publication Beilstein journal of nanotechnology Abbreviated Journal Beilstein J Nanotech
Volume 3 Issue Pages 789-797
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Recent advances in near-edge X-ray-absorption fine-structure spectroscopy coupled with transmission X-ray microscopy (NEXAFS-TXM) allow large-area mapping investigations of individual nano-objects with spectral resolution up to E/Delta E = 104 and spatial resolution approaching 10 nm. While the state-of-the-art spatial resolution of X-ray microscopy is limited by nanostructuring process constrains of the objective zone plate, we show here that it is possible to overcome this through close coupling with high-level theoretical modelling. Taking the example of isolated bundles of hydrothermally prepared sodium titanate nanotubes ((Na,H)TiNTs) we are able to unravel the complex nanoscale structure from the NEXAFS-TXM data using multichannel multiple-scattering calculations, to the extent of being able to associate specific spectral features in the O K-edge and Ti L-edge with oxygen atoms in distinct sites within the lattice. These can even be distinguished from the contribution of different hydroxyl groups to the electronic structure of the (Na,H)TiNTs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000311482400001 Publication Date 2012-11-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-4286; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.127 Times cited 13 Open Access
Notes Approved Most recent IF: 3.127; 2012 IF: 2.374
Call Number (down) UA @ lucian @ c:irua:105140 Serial 3684
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Author Beheshtian, J.; Sadeghi, A.; Neek-Amal, M.; Michel, K.H.; Peeters, F.M.
Title Induced polarization and electronic properties of carbon-doped boron nitride nanoribbons Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 19 Pages 195433-195438
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic properties of boron nitride nanoribbons (BNNRs) doped with a line of carbon atoms are investigated using density functional calculations. By replacing a line of alternating B and N atoms with carbons, three different configurations are possible depending on the type of the atoms which bond to the carbons. We found very different electronic properties for these configurations: (i) the NCB arrangement is strongly polarized with a large dipole moment having an unexpected direction, (ii) the BCB and NCN arrangements are nonpolar with zero dipole moment, (iii) the doping by a carbon line reduces the band gap regardless of the local arrangement of the borons and the nitrogens around the carbon line, and (iv) the polarization and energy gap of the carbon-doped BNNRs can be tuned by an electric field applied parallel to the carbon line. Similar effects were found when either an armchair or zigzag line of carbon was introduced.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000311694200006 Publication Date 2012-11-29
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 41 Open Access
Notes ; We would like to thank J. M. Pereira and S. Goedecker for helpful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CONGRAN. M. N.-A is supported by EU-Marie Curie IIF postdoc Fellowship/299522. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number (down) UA @ lucian @ c:irua:105136 Serial 1603
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Author Croitoru, M.D.; Vagov, A.; Shanenko, A.A.; Axt, V.M.
Title The Cooper problem in nanoscale : enhancement of the coupling due to confinement Type A1 Journal article
Year 2012 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 25 Issue 12 Pages 124001-124005
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In 1956 Cooper demonstrated (1956 Phys. Rev. 104 1189) that, no matter how weak the attraction is, two electrons in three-dimensional (3D) space just above the Fermi sea could be bound. In this work we investigate the influence of confinement on the binding energy of a Cooper pair. We show that confinement-induced modification of the Fermi sea results in a significant increase of the binding energy, when the bottom of an energy subband is very close to the Fermi surface.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000311418100004 Publication Date 2012-11-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 9 Open Access
Notes ; MDC acknowledges support by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; Approved Most recent IF: 2.878; 2012 IF: 2.758
Call Number (down) UA @ lucian @ c:irua:105121 Serial 3573
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Author Bogaerts, A.; Aerts, R.; Snoeckx, R.; Somers, W.; Van Gaens, W.; Yusupov, M.; Neyts, E.
Title Modeling of plasma and plasma-surface interactions for medical, environmental and nano applications Type A1 Journal article
Year 2012 Publication Journal of physics : conference series Abbreviated Journal
Volume 399 Issue Pages 012011
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this paper, an overview is given of modeling investigations carried out in our research group for a better understanding of plasmas used for medical, environmental and nano applications. The focus is both on modeling the plasma chemistry and the plasma-surface interactions. The plasma chemistry provides the densities and fluxes of the important plasma species. This information can be used as input when modeling the plasma-surface interactions. The combination of plasma simulations and plasma – surface interaction simulations provides a more comprehensive understanding of the underlying processes for these applications.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000312261700011 Publication Date 2012-11-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588;1742-6596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 7 Open Access
Notes Approved Most recent IF: NA
Call Number (down) UA @ lucian @ c:irua:104727 Serial 2130
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Author Krekels, T.; Zou, H.; Van Tendeloo, G.; Wagener, D.; Buchgeister, M.; Hosseini, S.M.; Herzog, P.
Title Ortho-II structure in ABa2Cu3O7-\delta compounds (A=Er, Nd, Pr, Sm, Yb) Type A1 Journal article
Year 1992 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 196 Issue 3-4 Pages 363-368
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Oxygen ordering has been investigated in superconducting ABa2Cu3O7-delta ceramic materials with A = Er, Nd, Sm and Yb, as well as in samples of this type with the rate earth A partially substituted by Pr. The critical temperature T(c) was determined as a function of the oxygen deficiency-delta of the compound and the corresponding microstructures were investigated by electron diffraction and electron microscopy. A distinct relationship exists between the width of the 60 K plateau and the ortho II ordering. Our results show that the ortho II ordered phase is the superconducting phase with a characteristic T(c) of 60 K.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1992JC73400021 Publication Date 2002-10-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.942 Times cited 52 Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number (down) UA @ lucian @ c:irua:104547 Serial 2531
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Author Vanhellemont, J.; Maes, H.E.; Schaekers, M.; Armigliato, A.; Cerva, H.; Cullis, A.; de Sande, J.; Dinges, H.; Hallais, J.; Nayar, V.; Pickering, C.; Stehlé, J.L.; Van Landuyt, J.; Walker, C.; Werner, H.; Salieri, P.;
Title Round-robin investigation of silicon-oxide on silicon reference materials for ellipsometry Type A1 Journal article
Year 1993 Publication Applied surface science T2 – SYMP ON DIAGNOSTIC TECHNIQUES FOR SEMICONDUCTOR MATERIALS ANALYSIS AND, FABRICATION PROCESS CONTROL, AT THE 1992 SPRING CONF OF THE EUROPEAN, MATERIALS RESEARCH SOC, JUN 02-05, 1992, STRASBOURG, FRANCE Abbreviated Journal Appl Surf Sci
Volume 63 Issue 1-4 Pages 45-51
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The main results and conclusions are presented of a round robin study of silicon oxide on silicon reference samples for ellipsometry. The oxide films with nominal thicknesses of 10, 50 and 120 nm are grown by thermal oxidation. The oxide film thicknesses have been determined by single wavelength ellipsometry (SWE), by spectroscopic ellipsometry (SE) and by cross-sectional conventional and high-resolution transmission electron microscopy (TEM and HREM) in different laboratories. The main conclusions are that special precautions have to be taken in order to use TEM as a reliable thickness measurement technique; that single wavelength ellipsometry can be used with great accuracy and reproducibility for the 50 and 120 nm film thicknesses but that it shows some inherent problems for the 10 nm films; and that spectroscopic ellipsometry showed for all film thicknesses an accuracy and reproducibility which is clearly superior to that of SWE.
Address
Corporate Author Thesis
Publisher Elsevier science bv Place of Publication Amsterdam Editor
Language Wos A1993KF03400009 Publication Date 2002-10-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-4332; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.711 Times cited 13 Open Access
Notes Approved
Call Number (down) UA @ lucian @ c:irua:104539 Serial 2932
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Author Martin, C.; Hervieu, M.; Huvé, M.; Michel, C.; Maignan, A.; Van Tendeloo, G.; Raveau, B.
Title Lead-mercury-based superconductors – the 1212-cuprate Pb0.7Hg0.3Sr2+xCa0.7Nd0.3-xCu2O7-\delta and the new oxycarbonate Pb0.7Hg0.3Sr4Cu2CO3O7 Type A1 Journal article
Year 1994 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 222 Issue 1-2 Pages 19-26
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new superconducting mercury oxycarbonate, Pb0.7Hg0.3Sr4Cu2CO3O7, has been synthesized. This tetragonal phase (a = 3.824 angstrom, c= 16.468 angstrom) consists of an intergrowth of two nonsuperconducting compounds, Sr2CuO2CO3 and Pb0.7Hg0.3Sr2CuO5. It exhibits after optimization a critical temperature of 70 K, with a sharp transition and a superconducting volume fraction of 50%. Its behavior can be compared to that of thallium oxycarbonates previously isolated. This study is completed by a reinvestigation of the 1212 cuprate of the system Hg-Pb-Sr-Ca-Nd-Cu. A superconducting phase with the 1212 structure, similar to that previously obtained but with a significantly different composition, Pb0.7Hg0.3Sr2+xCa0.7Nd0.3-xCu2O7, has been obtained, with a T(c onset) of 100 K. The behavior of the latter is compared with other lead-based 1212 cuprates.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos A1994NB49400004 Publication Date 2002-10-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.942 Times cited 49 Open Access
Notes Approved no
Call Number (down) UA @ lucian @ c:irua:104517 Serial 1813
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Author Raveau, B.; Michel, C.; Hervieu, M.; Van Tendeloo, G.; Maignan, A.
Title Stabilization of mercury-based superconductors by foreign cations Type A1 Journal article
Year 1994 Publication Annales de chimie (1914) T2 – 4th North-African Materials Science Symposium (JMSM 94), NOV 23-24, 1994, CASABLANCA, MOROCCO Abbreviated Journal 4th North-African Materials Science Symposium (JMSM 94), NOV 23-24, 1994, CASABLANCA, MOROCCO
Volume 19 Issue 7-8 Pages 487-492
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The recently discovered superconducting mercury-based cuprates HgBa2Can-1CunO2n+2+delta have proved difficult to synthesize as single phases and are sensitive to environment (CO2, moisture). The present paper gives an overview of new series mercury based superconductors, whose stabilisation is based on the fact that a foreign cation with a higher valency than Hg(II) must be introduced in the mercury layers, in order to fill up partially the oxygen vacancies of these layers. By this method, several new series of superconductors involving strontium instead of barium with critical temperatures ranging from 27 K to 95 K have been isolated : Hg0.5Bi0.5Sr2-xLaxCuO4+delta, Hg(0.5)Bi(0.5)Sr(2)Ca(1-x)R(x)Cu(2)O(6+delta) (R Y, Nd, Pr), Pb0.7Hg0.3Sr2-xLaxCuO4+delta, Pb(0.7)Hg(0.3)Sr(2)Ca(1-x)R(x)Cu(2)O(6+delta) (R = Y, Nd) Hg(1-x)Pr(x)Sr(2)A(1-x')Pr(x') Cu2O6+delta (A = Sr, Ca), Pb0.7Hg0.3Sr2Cu2CO3O7 and Hg1-xCrxSr2CuO4+delta. The behaviour of the praseodymium cuprates that exhibit a rather sharp transition and reach a Tc of 85 K is especially discussed. A method to synthesize new ''Ba-Hg'' superconducting cuprates with the 1212 structure at normal pressure with a Tc up to 110 K is also presented.
Address
Corporate Author Thesis
Publisher Place of Publication Paris Editor
Language Wos A1994RC75300027 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0151-9107 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number (down) UA @ lucian @ c:irua:104472 Serial 3137
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Author Huve, M.; Martin, C.; Maignan, A.; Michel, C.; Van Tendeloo, G.; Hervieu, M.; Raveau, B.
Title A new cuprate with mercury bilayers : the “2222” oxide Hg2-xMxBa2Pr2Cu2O10-\delta (M= Cu,Pr) Type A1 Journal article
Year 1995 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 114 Issue 1 Pages 230-235
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A ''2222'' cuprate with mercury bilayers (Hg1.5Cu0.2Pr0.3)Ba2Pr2Cu2O10-delta, has been synthesized for the first time. It crystallizes in the P4/nmm space group with a = 3.9072(1) Angstrom and c = 17.219(1) Angstrom. The powder XRD and HREM studies of this new cuprate show that its structure consists of an intergrowth of double pyramidal (oxygen-deficient perovskite) copper layers, with double fluorite-type layers and distorted triple rock salt layers (mercury bilayers). The structure of this phase can be deduced from that of the ''2212'' mercury cuprate (Hg1.5Cu0.2Pr0.3)Ba2PrCu2O8-delta by the introduction of one additional [PrO2]infinity fluorite layer. The regular stacking of the metallic layer and the uniform cationic distribution in the mercury bilayers are remarkable features of this cuprate. The stabilization of the mercury bilayers by praseodymium and the absence of superconductivity are discussed. (C) 1995 Academic Press, Inc.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1995QA17000033 Publication Date 2002-10-07
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 2.133 Times cited 6 Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number (down) UA @ lucian @ c:irua:104448 Serial 2310
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Author Radaelli, P.G.; Marezio, M.; Tholence, J.L.; Debrion, S.; Santoro, A.; Huang, Q.; Capponi, J.J.; Chaillout, C.; Krekels, T.; Van Tendeloo, G.
Title Crystal-structure of the double-hg-layer copper-oxide superconductor (Hg,Pr)2Ba2(Y,Ca)Cu2O8-\deltaas a function of doping Type A1 Journal article
Year 1995 Publication The journal of physics and chemistry of solids Abbreviated Journal J Phys Chem Solids
Volume 56 Issue 10 Pages 1471-1478
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of the newly discovered double-Hg-layer copper oxide superconductor (Hg, Pr)(2)Ba-2(Y, Ca)Cu2O8-delta was studied as a function of chemical doping using neutron and electron diffraction and high-resolution transmission electron microscopy (HREM). Rietveld refinements of the structural parameters from neutron powder diffraction data indicate that the oxygen site O3 on the mercury plane is highly defective, being both partially occupied and displaced from the high-symmetry position. The variable concentration of oxygen vacancies partially compensates for the cation doping and, together with the O3 displacement field, makes some of the Hg atoms acquire an unusual pyramidal coordination. HREM images confirm that the structure is of the '2212' type, with very few defects. In some grains, faint superstructure reflections were evidenced by electron diffraction, suggesting that both the oxygen vacancies and the O3 displacement field may order at least on a local scale.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos A1995RR95600025 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3697; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.853 Times cited 16 Open Access
Notes Approved no
Call Number (down) UA @ lucian @ c:irua:104423 Serial 574
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Author Shi, J.M.; Koenraad, P.M.; van de Stadt, A.F.W.; Peeters, F.M.; Devreese, J.T.; Wolter, J.H.
Title Electronic structure of a Si \delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier Type A1 Journal article
Year 1996 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 54 Issue 11 Pages 7996-8004
Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Abstract We present a theoretical study of the electronic structure of a heavily Si delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier. In this class of structures the effect of DX centers on the electronic properties can be tuned by changing the AlxGa1-xAs barrier width and/or the Al concentration, which leads to a lowering of the DX level with respect to the Fermi energy without disturbing the wave functions much. A self-consistent approach is developed in which the effective confinement potential and the Fermi energy of the system, the energies, the wave functions, and the electron densities of the discrete subbands have been obtained as a function of both the material parameters of the samples and the experimental conditions. The effect of DX centers on such structures at nonzero temperature and under an external pressure is investigated for three different models: (1) the DX(nc)(0) model with no correlation effects, (2) the d(+)/DX(0) model, and (3) the d(+)/DX(-) model with inclusion of correlation effects. In the actual calculation, influences of the background accepters, the discontinuity of the effective mass of the electrons at the interfaces of the different materials, band nonparabolicity, and the exchange-correlation energy of the electrons have been taken into account. We have found that (1) introducing a quantum barrier into delta-doped GaAs makes it possible to control the energy gaps between different electronic; subbands; (2) the electron wave functions are mon spread out when the repellent effect of the barriers is increased as compared to those in delta-doped GaAs; (3) increasing the quantum-barrier height and/or the application of hydrostatic pressure are helpful to experimentally observe the effect of the DX centers through a decrease of the total free-electron density; and (4) the correlation effects of the charged impurities are important for the systems under study.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1996VL14500066 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 11 Open Access
Notes Approved no
Call Number (down) UA @ lucian @ c:irua:104388 Serial 1012
Permanent link to this record
 

 
Author Verbist, K.; Tafuri, F.; Granozio, F.M.; Di Chiara, S.; Van Tendeloo, G.
Title Microstructure of artificial [100] 45 degrees twist grain boundaries in YBa2Cu3O7-delta Type P1 Proceeding
Year 1998 Publication Electron Microscopy 1998, Vol 2: Materials Science 1 Abbreviated Journal
Volume Issue Pages 593-594
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000077019900291 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0565-7 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (down) UA @ lucian @ c:irua:104356 Serial 2066
Permanent link to this record
 

 
Author Maignan, A.; Martin, C.; Van Tendeloo, G.; Hervieu, M.; Raveau, B.
Title Size mismatch : a crucial factor for generating a spin-glass insulator in manganites Type A1 Journal article
Year 1999 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 60 Issue 22 Pages 15214-15219
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Thr structural, electronic, and magnetic properties of the highly mismatched perovskite oxides, Th(0.35)A(0.65)MnO(3), where Ais for the alkaline earth divalent cations (Ca, Ba, Sr), which are all characterized by the same large tolerance factor (t=0.934), have been investigated by using electron microscopy, electrical resistivity, magnetic susceptibility, and magnetization. It is clearly established that a transition from ferromagnetic metallic towards spin-glass insulator samples is induced as the A-site cationic size mismatch is increased. Moreover, the magnetoresistance (MR) properties of these manganites are strongly reduced for the spin-glass insulators, demonstrating that the A-sire cationic disorder is detrimental for the colossal MR properties. Based on these results, a new electronic and magnetic diagram is established that shows that the A-site disorder, rather than the A-site average cationic size (or t) is the relevant factor for generating spin-glass insulating manganites. [S0163-1829(99)01746-4].
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000084631600039 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 75 Open Access
Notes Approved Most recent IF: 3.836; 1999 IF: NA
Call Number (down) UA @ lucian @ c:irua:104280 Serial 3038
Permanent link to this record
 

 
Author Charlier, E.; Gijbels, R.; Van Doorselaer, M.; De Keyzer, R.
Title Determination of the silver sulphide cluster size distribution via computer simulations Type H1 Book chapter
Year 2000 Publication Abbreviated Journal
Volume Issue Pages 85-89
Keywords H1 Book chapter; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Addition of a labile sulphur donor to light sensitive silver halide microcrystals results in the formation of a distribution of silver sulphide clusters on the crystal surface. These silver sulphide clusters enhance the efficiency of image formation during the photographic process. Their activity towards the capturing of light photons, however, is very critical to their size (aggregation number) and concentration. By incorporating gold ions into silver sulphide clusters it was possible to monitor the size distribution by measuring the amount of gold reacted. From these experiments, no evidence was found for aggregation of the reacted sulphur entities on the surface. The uptake of gold ions at different sulphur concentrations could well be fitted with a simulated size distribution when a catalyzed deposition of sulphur was assumed, with a reactivity of the surface equal to 1.0 % for the microcrystals studied. From a simulation of the silver sulphide cluster size distribution a correlation could also be found between increasing aggregation numbers and the absorption at increasing wavelengths in diffuse reflectance spectroscopy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000183315900021 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 0-89208-229-1 Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number (down) UA @ lucian @ c:irua:104275 Serial 679
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Author Schuddinck, W.; Van Tendeloo, G.; Barnabé, A.; Hervieu, M.; Raveau, B.
Title Relation between structure, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites Type A1 Journal article
Year 2000 Publication Journal of magnetism and magnetic materials T2 – Symposium G Material Physics Issues and Applications of Magnetic Oxides, at the E-MRS Spring Meeting, JUN 01-04, 1999, Strasbourg, France Abbreviated Journal J Magn Magn Mater
Volume 211 Issue 1-3 Pages 105-110
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The relationships between incommensurability, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites have been studied by electron diffraction and lattice imaging versus temperature with 0.02 less than or equal to x less than or equal to 0.07. All compositions show an incommensurate superstructure over the whole temperature domain, despite the fact that they are ferromagnetic and conductive below 140 K, The q-vector (1/2 – delta)a* decreases with increasing temperature for all compositions x. For a given temperature q also decreases with x. Lattice images obtained at low temperature give a clear view of the characteristics of the incommensurate structure. They also provide a better understanding of the charge ordering process. The low-temperature form of the Cr-doped manganites is not a perfectly doubled cell [[2a(p)root 2 x 2a(p) x a(p)root 2]], but defects inducing a tripled cell occur pseudo-periodically. (C) 2000 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000085772100017 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-8853; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.63 Times cited 16 Open Access
Notes Approved Most recent IF: 2.63; 2000 IF: 0.996
Call Number (down) UA @ lucian @ c:irua:104256 Serial 2858
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Author Dluzewski, P.; Pietraszko, A.; Kozlowski, M.; Szczepanska, A.; Gorecka, J.; Baran, M.; Leonyuk, L.; Babonas, G.J.; Lebedev, O.I.; Szymczak, R.
Title Electron microscopy and X-ray structural investigations of incommensurate spin-ladder Sr4.1Ca4.7Bi0.3Cu17O29 single crystals Type A1 Journal article
Year 2000 Publication Acta physica Polonica: A: general physics, solid state physics, applied physics Abbreviated Journal Acta Phys Pol A
Volume 98 Issue 6 Pages 729-737
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Transmission electron microscopy and X-ray diffraction proved chain/ladder incommensurate single crystal structure of investigated samples. The incommensurate ratio was determined from the X-ray and electron diffraction being equal to 0.704. Diffuse scattering intensities localised on the planes perpendicular to the c*-axis and passing through the spots originating from the periodicity of chain sublattice were detected. High-angle grain boundary or twinning formed by rotation of 33.3 degrees around [100] direction was observed. High-resolution electron microscopy images revealed the stacking faults in ac planes.
Address
Corporate Author Thesis
Publisher Place of Publication Warszawa Editor
Language Wos 000166377600007 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0587-4246 ISBN Additional Links UA library record; WoS full record;
Impact Factor 0.469 Times cited Open Access
Notes Approved Most recent IF: 0.469; 2000 IF: 0.409
Call Number (down) UA @ lucian @ c:irua:104226 Serial 951
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Author Lei, C.H.; Van Tendeloo, G.; Siegert, M.; Schubert, J.; Buchal, C.
Title Structural investigation of the epitaxial yittria-stabilized zirconia films deposited on (001) silicon by laser ablation Type A1 Journal article
Year 2001 Publication Journal of crystal growth Abbreviated Journal J Cryst Growth
Volume 222 Issue 3 Pages 558-564
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Yittria-stabilized zirconia (YSZ) films doped with 3 and 9 vol%. Y(2)O(3), respectively, are epitaxially deposited on (0 0 1) silicon substrates by means of pulsed laser deposition (PLD) technique. Transmission electron microscopy (TEM) and X-ray diffraction are mainly combined to study the film microstructure. It is: found that the film structure strongly depends on the amount of Y(2)O(3) dopant. 99/0 Y(2)O(3)-doped films display a near cubic structure; 45 degrees 1/2(1 1 0) dislocations are the main defects in the film and thermal cracks are formed during cooling. The 3% Y(2)O(3)-doped films are dominated by {1 1 0} twin-related tetragonal domains in which monoclinic phase is found. The films are free of thermal cracks even for films thicker than 2 mum. (C) 2001 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000166701500020 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-0248; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.751 Times cited 12 Open Access
Notes Approved Most recent IF: 1.751; 2001 IF: 1.283
Call Number (down) UA @ lucian @ c:irua:104211 Serial 3240
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Author Tokei, Z.; Lanckmans, F.; van den Bosch, G.; Van Hove, M.; Maex, K.; Bender, H.; Hens, S.; van Landuyt, J.
Title Reliability of copper dual damascene influenced by pre-clean Type P1 Proceeding
Year 2002 Publication Analysis Of Integrated Circuits Abbreviated Journal
Volume Issue Pages 118-123
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Ieee Place of Publication New york Editor
Language Wos 000177689400022 Publication Date 2003-06-25
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 5 Open Access
Notes Conference name: Approved Most recent IF: NA
Call Number (down) UA @ lucian @ c:irua:104170 Serial 2865
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Author Anisimovas, E.; Peeters, F.M.
Title Correlated few-particle states in artificial bipolar molecule Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue 23 Pages 233302-233304
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the ground and excited states of a bipolar artificial molecule composed of two vertically coupled quantum dots containing different type of carriers-electrons and holes-in equilibrium. The approach based on exact diagonalization is used and reveals an intricate pattern of ground-state angular momentum switching and a rearrangement of approximate single-particle levels as a function of the interdot coupling strength.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000176767900019 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 14 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number (down) UA @ lucian @ c:irua:104154 Serial 519
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Author Fleurov, V.; Ivanov, V.A.; Peeters, F.M.; Vagner, I.D.
Title Spin-engineered quantum dots Type A1 Journal article
Year 2002 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E
Volume 14 Issue 4 Pages 361-365
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Spatially nonhomogeneously spin polarized nuclei are proposed as a new mechanism to monitor electron states in a nanostructure, or as a means to create and, if necessary, reshape such nanostructures in the course of the experiment. We found that a polarization of nuclear spins may lift the spin polarization of the electron states in a nanostructure and, if sufficiently strong, leads to a polarization of the electron spins. Polarized nuclear spins may form an energy landscape capable of binding electrons with energy up to several meV and the localization radius > 100 Angstrom. (C) 2002 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000177511900003 Publication Date 2002-10-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.221 Times cited 12 Open Access
Notes Approved Most recent IF: 2.221; 2002 IF: 1.107
Call Number (down) UA @ lucian @ c:irua:104150 Serial 3088
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Author Vodolazov, D.Y.; Baelus, B.J.; Peeters, F.M.
Title Stationary-phase slip state in quasi-one-dimensional rings Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 66 Issue 5 Pages 054531-54536
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The nonuniform superconducting state in a ring in which the order parameter vanishing at one point is studied. This state is characterized by a jump of the phase by pi at the point where the order parameter becomes zero. In uniform rings such a state is a saddle-point state and consequently unstable. However, for nonuniform rings with, e.g., variations of geometrical or physical parameters or with attached wires this state can be stabilized and may be realized experimentally.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000177873000137 Publication Date 2002-10-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 29 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number (down) UA @ lucian @ c:irua:104147 Serial 3152
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Author Peeters, F.M.; Vasilopoulos, P.; Shi, J.
Title Density of states and Fermi level of a periodically modulated two-dimensional electron gas Type A1 Journal article
Year 2002 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 14 Issue 38 Pages 8803-8816
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Explicit analytic expressions are obtained for the density of states D(E) and Fermi energy E-F of a two-dimensional electron gas in the presence of a weak and periodic unidirectional electric or magnetic modulation and of a uniform perpendicular magnetic field B. The Landau levels broaden into bands and their width, proportional to the modulation strength, oscillates with B and gives rise to Weiss oscillations in D(E), E-F and the transport coefficients. When both electric and magnetic modulations are present the position of the resulting oscillations depends on the ratio delta between the two modulation strengths. When the modulations are out of phase there is no shift in the position of the oscillations when delta varies and for a particular value of delta the oscillations are suppressed.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000178678400008 Publication Date 2002-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 8 Open Access
Notes Approved Most recent IF: 2.649; 2002 IF: 1.775
Call Number (down) UA @ lucian @ c:irua:104140 Serial 640
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Author Bogaerts, A.; Grozeva, M.
Title Effect of helium/argon gas ratio in a He-Ar-Cu+ IR hollow-cathode discharge laser : modeling study and comparison with experiments Type A1 Journal article
Year 2003 Publication Applied physics B : lasers and optics Abbreviated Journal Appl Phys B-Lasers O
Volume 76 Issue 3 Pages 299-306
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The He-Ar-Cu+ IR laser operates in a hollow-cathode discharge, typically in a mixture of helium with a few-% Ar. The population inversion of the Cu+ ion levels, responsible for laser action, is attributed to asymmetric charge transfer between He+ ions and sputtered Cu atoms. The Ar gas is added to promote sputtering of the Cu cathode. In this paper, a hybrid modeling network consisting of several different models for the various plasma species present in a He-Ar-Cu hollow-cathode discharge is applied to investigate the effect of Ar concentration in the gas mixture on the discharge behavior, and to find the optimum He/Ar gas ratio for laser operation. It is found that the densities of electrons, Ar+ ions, Ar-m* metastable atoms, sputtered Cu atoms and Cu+ ions increase upon the addition of more Ar gas, whereas the densities of He+ ions, He-2(+) ions and He-m* metastable atoms drop considerably. The product of the calculated Cu atom and He+ ion densities, which determines the production rate of the upper laser levels, and hence probably also the laser output power, is found to reach a maximum around 1-5% Ar addition. This calculation result is compared to experimental measurements, and reasonable agreement has been reached.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000182758000017 Publication Date 2004-03-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0946-2171;1432-0649; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.696 Times cited 6 Open Access
Notes Approved Most recent IF: 1.696; 2003 IF: 2.012
Call Number (down) UA @ lucian @ c:irua:104125 Serial 812
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Author Ferreira, W.P.; Matulis, A.; Farias, G.A.; Peeters, F.M.
Title Structure and correlations in two-dimensional classical artificial atoms confined by a Coulomb potential Type A1 Journal article
Year 2003 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 67 Issue 4Part 2 Pages 046601-46608
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The ordering of N equally charged particles (-e) moving in two dimensions and confined by a Coulomb potential, resulting from a displaced positive charge Ze is discussed. This is a classical model system for atoms. We obtain the configurations of charged particles which, depending on the value of N and Z, may result in ring structures, hexagonal-type configurations, and for N/Z approximate to 1 in an inner structure of particles which is separated by an outer ring of particles. For N/Z << 1, the Hamiltonian of the parabolic confinement case is recovered. For N/Z approximate to 1, the configurations are very different from those found in the case of a parabolic confinement potential. A hydrodynamic analysis is presented in order to highlight the correlations effects.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000182825400087 Publication Date 2003-04-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-651X;1095-3787; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 14 Open Access
Notes Approved Most recent IF: 2.366; 2003 IF: 2.202
Call Number (down) UA @ lucian @ c:irua:104123 Serial 3273
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Author Vasilopoulos, P.; Wang, X.F.; Peeters, F.M.; Chowdhury, S.; Long, A.R.; Davies, J.H.
Title Magneto resistance oscillations in a modulated 2DEG periodic in the ratio h/e to flux per unit cell Type A1 Journal article
Year 2004 Publication Physica. E: Low-dimensional systems and nanostructures T2 – 15th International Conference on Electronic Properties of, Two-Dimensional Systems (EP2DS-15), JUL 14-18, 2003, Nara, JAPAN Abbreviated Journal Physica E
Volume 22 Issue 1-3 Pages 389-393
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Transport properties of the 2DEG are studied in the presence of a normal magnetic field B and of a weak, two-dimensional periodic potential modulation. A tight-binding treatment has shown that each Landau level splits into several subbands with exponentially small gaps between them. Assuming the latter are closed due to disorder gives analytical wave functions and simplifies the evaluation of the magnetoresistance tensor p(muv) The relative phase of the oscillations in p(xx) and p(yy) depends on the modulation strengths and periods. For short periods less than or equal to 100 nm, in addition to the Weiss oscillations, the collisional contribution to the conductivity and the corresponding resistivity contribution show prominent peaks when one flux quantum h/e passes through an integral number of unit cells in good agreement with experiments. For periods 300-400 nm long used in early experiments, these peaks occur at fields 10-25 times smaller than those of the Weiss oscillations and are not resolved. (C) 2003 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000221140800094 Publication Date 2004-02-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links UA library record; WoS full record
Impact Factor 2.221 Times cited Open Access
Notes Approved Most recent IF: 2.221; 2004 IF: 0.898
Call Number (down) UA @ lucian @ c:irua:104107 Serial 1911
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Author Krstajic, P.; Peeters, F.M.
Title Spin-dependent tunneling in diluted magnetic semiconductor trilayer structures Type A1 Journal article
Year 2005 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 72 Issue 12 Pages 125350-125356
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Tunneling of holes through a trilayer structure made of two diluted magnetic semiconductors, (Ga,Mn)As, separated by a thin layer of nonmagnetic AlAs is investigated. The problem is treated within the 6x6 Luttinger-Kohn model for valence bands with the split-off band included. The influence of the spin-orbit coupling is pronounced as the spin-splitting Delta(ex) is comparable with the split-off Delta(SO) splitting. It is assumed that direct tunneling is the dominant mechanism due to the high quality of the tunnel junctions. Our theoretical results predict the correct order of magnitude for the tunneling magnetoresistance ratio, but various other effects, such as scattering on impurities and defects, should be included in order to realize a quantitative agreement with experiment.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000232229400116 Publication Date 2005-09-30
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 8 Open Access
Notes Approved Most recent IF: 3.836; 2005 IF: 3.185
Call Number (down) UA @ lucian @ c:irua:104068 Serial 3086
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Author Ferreira, W.P.; Peeters, F.M.; Farias, G.A.
Title Melting and evaporation in classical two-dimensional clusters confined by a Coulomb potential Type A1 Journal article
Year 2005 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 72 Issue 4 Part 1 Pages 041502-41507
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The thermal properties of a two-dimensional classical cluster of negatively charged particles bound by a punctual positive charge are presented. The melting phenomenon is analyzed and the features which characterize such a solid-liquid transition are highlighted. We found that the presence of metastable states strongly modifies the melting scenario, and that the melting temperature of the system is determined by the height of the saddle point energy separating the ground state and the metastable state. Due to the particular type of confinement potential considered in this paper, we also found that, at sufficiently large temperature, the cluster can become thermally ionized.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000232930600030 Publication Date 2005-10-06
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 4 Open Access
Notes Approved Most recent IF: 2.366; 2005 IF: 2.418
Call Number (down) UA @ lucian @ c:irua:104067 Serial 1983
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Author Sreckovic, M.Z.; Tomic, E.; Ostojic, S.M.; Ilic, J.T.; Bundaleski, N.; Sekulic, R.S.; Mlinar, V.
Title The application of laser beam diffraction and scattering methods in the measurement of shape and determination of material parameters Type A1 Journal article
Year 2007 Publication Lasers in Engineering (Old City Publishing) Abbreviated Journal Laser Eng
Volume 17 Issue 3-4 Pages 179-196
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Lasers can be used for many applications including determination of size, in addition to the theory of diffraction and material dispersion phenomena. In this paper we calculated the corrections in angular intensity for the Gaussian and uniform particle distributions, the scattering intensity on cylindrical objects. We also evaluated the necessary mathematical summations. In addition, we analyse and Simulate the special positions of detectors using laser Doppler anemometric (LDA) methods, which can be used to determine the particle diameter. The dispersion measurements for actual fibres are given at the end. The geometric and material parameters of these fibres were taken before the evaluation of the angular scattering intensity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0898-1507 ISBN Additional Links UA library record; WoS full record;
Impact Factor 0.214 Times cited Open Access
Notes Approved Most recent IF: 0.214; 2007 IF: 0.188
Call Number (down) UA @ lucian @ c:irua:104050 Serial 3571
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Author Krsmanovic, R.; Morozov, V.A.; Lebedev, O.I.; Polizzi, S.; Speghini, A.; Bettinelli, M.; Van Tendeloo, G.
Title Structural and luminescence investigation on gadolinium gallium garnet nanocrystalline powders prepared by solution combustion synthesis Type A1 Journal article
Year 2007 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 18 Issue 32 Pages 325604-325609
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Nanocrystalline powders of undoped and lanthanide (Pr3+, Tm3+)- doped gadolinium gallium garnet, Gd3Ga5O12 (GGG), were prepared by propellant synthesis and studied by x-ray powder diffraction (XRD), electron diffraction (ED), high-resolution electron microscopy (HREM) and luminescence spectroscopy. The x-ray diffraction patterns of the GGG samples were analysed using the Rietveld method. The Rietveld refinement reveals the existence of two garnet-type phases: both are cubic (space group Ia $(3) over bar $d) with a slightly different lattice parameter and probably a slightly different composition. Electron diffraction and electron microscopy measurements confirm the x-ray diffraction results. EDX measurements for lanthanide-doped samples show that stable solid solutions with composition Gd(3-x)Ln(x)Ga(5)O(12), x approximate to 0.3 ( Ln = Pr; Tm) have been obtained. The luminescence properties of the Tm3+ -doped nanocrystalline GGG samples were measured and analysed.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000248231300010 Publication Date 2007-07-14
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 33 Open Access
Notes Iap5-01 Approved Most recent IF: 3.44; 2007 IF: 3.310
Call Number (down) UA @ lucian @ c:irua:104042 Serial 3195
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Author Dzhurakhalov, A.A.; Atanasov, I.; Hou, M.
Title Calculation of binary and ternary metallic immiscible clusters with icosahedral structures Type A1 Journal article
Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume Issue Pages 115415
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Recently, core-shell Ag-Co, Ag-Cu, and “onionlike” Cu-Co equilibrium configurations were predicted in the case of isolated face centered cubic (fcc) bimetallic clusters, and three shell onionlike configurations were predicted in the case of ternary metallic clusters with spherical and truncated octahedral morphologies. In the present paper, immiscible binary CuCo and ternary AgCuCo clusters with icosahedral structures are studied as functions of their size and composition. Clusters studied are formed by 13, 55, 147, 309, and 561 atoms corresponding to the five smallest possible closed shell icosahedral structures. An embedded atom model potential is used to describe their cohesion. Equilibrium configurations are investigated by means of Metropolis Monte Carlo free energy minimization in the (NPT) canonical ensemble. Most simulations are achieved at 10 and 300 K. The effect of temperature on segregation ordering is systematically investigated. Selected cases are used to identify the effect of size and composition on melting. In contrast with fcc clusters, homogeneous onionlike configurations of binary clusters are not predicted. When it is allowed by the composition, a complete outer shell is formed by Cu in binary Cu-Co clusters and by Ag in ternary Ag-Cu-Co clusters. Depending on temperature, Co may precipitate into decahedral groups under the Cu vertices of the icosahedra in binary clusters, while the Co-Cu configuration in ternary clusters drastically depends on the Ag coating. Despite the multicomponent character of the clusters and the immiscibility of the species forming them, for most compositions and sizes, equilibrium structures remain close to perfectly icosahedral at 10 K as well as at 300 K.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000254542800167 Publication Date 2008-03-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes Approved Most recent IF: 3.836; 2008 IF: 3.322
Call Number (down) UA @ lucian @ c:irua:104033 Serial 4517
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