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Author Ivanov, V.A.; Krstajic, P.M.; Peeters, F.M.; Fleurov, V.; Kikoin, K.
Title On the nature of ferromagnetism in dilute magnetic semiconductors : GaAs:Mn and GaP:Mn Type A1 Journal article
Year 2003 Publication Journal of magnetism and magnetic materials T2 – 2nd Moscow International Symposium on Magnetism (MISM 2001), JUN 20-24, 2001, MOSCOW STATE UNIV, MOSCOW, RUSSIA Abbreviated Journal J Magn Magn Mater
Volume 258 Issue Pages 237-240
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract On the basis of a simplified Hamiltonian for transition metal impurities in diluted magnetic semiconductors (DMS), the nature of ferromagnetism in p-type III-V DMS are investigated. Ferromagnetism is governed by the Anderson-Hubbard parameter for 3d electrons of Mn2+ and their strong hybridization with the hole carriers in the semiconducting medium. The origin of ferromagnetism in these materials has similarity with the Zener mechanism. From the energetically preferable parallel orientation of Mn spins the Curie temperature is calculated for GaAs:Mn. (C) 2002 Published by Elsevier Science B.V.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000181702000062 Publication Date 2003-03-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-8853; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.63 Times cited 10 Open Access
Notes Approved Most recent IF: 2.63; 2003 IF: 0.910
Call Number UA @ lucian @ c:irua:103311 Serial 2442
Permanent link to this record
 
 
Author Chang, K.; Xia, J.B.; Peeters, F.M.
Title Magnetic field tuning of the effective g factor in a diluted magnetic semiconductor quantum dot Type A1 Journal article
Year 2003 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 82 Issue 16 Pages 2661-2663
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The spin interaction and the effective g factor of a magnetic exciton (ME) are investigated theoretically in a diluted magnetic semiconductor (DMS) quantum dot (QD), including the Coulomb interaction and the sp-d exchange interaction. At low magnetic field, the ME energy decreases rapidly with increasing magnetic field and saturates at high magnetic field for high Mn concentration. The ground state of the ME exhibits an interesting crossing behavior between sigma(+)-ME and sigma(-)-ME for low Mn concentration. The g(ex) factor of the ME in a DMS QD displays a monotonic decrease with increasing magnetic field and can be tuned to zero by an external magnetic field. (C) 2003 American Institute of Physics.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000182258800037 Publication Date 2003-04-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 56 Open Access
Notes Approved Most recent IF: 3.411; 2003 IF: 4.049
Call Number UA @ lucian @ c:irua:103301 Serial 1878
Permanent link to this record
 
 
Author Cassiers, K.; van der Voort, P.; Linssen, T.; Vansant, E.F.; Lebedev, O.; van Landuyt, J.
Title A counterion-catalyzed (S0H+)(X-I+) pathway toward heat- and steam-stable mesostructured silica assembled from amines in acidic conditions Type A1 Journal article
Year 2003 Publication The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical Abbreviated Journal J Phys Chem B
Volume 107 Issue 16 Pages 3690-3696
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract An alternative pathway to assemble mesoporous molecular sieve silicas is developed using nonionic alkylamines and N,N-dimethylalkylamines (SO) as structure-directing agents in acidic conditions. The synthesized mesostructures possess wormhole-like frameworks with pore sizes and pore volumes in the range of 20-90 Angstrom and 0.5-1.3 cm(3)/g, respectively. The formation of the mesophase is controlled by a counterion-mediated mechanism of the type (S(0)H(+))(X(-)I(+)), where S(0)H(+) are protonated water molecules that are hydrogen bonded to the lone electron pairs on the amine surfactant headgroups (S(0)H(+)), X(-) is the counteranion originating from the acid, and I(+) are the positively charged (protonated) silicate species. We found that the stronger the ion X(-) is bonded to S(0)H(+), the more it catalyzes the silica condensation into (S(0)H(+))(X(-)I(+)). Br(-) is shown to be a strong binding anion and therefore a fast silica polymerization promoter compared to Cl(-) resulting in the formation of a higher quality mesophase for the Br(-) syntheses. We also showed that the polymerization rate of the silica, dictated by the counterion, controls the morphology of the mesostructures from nonuniform agglomerated blocks in the case of Br(-) syntheses to spherical particles for the Cl(-) syntheses. Next to many benefits such as low temperature, short synthesis time, and the use of inexpensive, nontoxic, and easily extractable amine templates, the developed materials have a remarkable higher thermal and hydrothermal stability compared to hexagonal mesoporous silica, which is also prepared with nonionic amines but formed through the S(0)I(0) mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000182350200005 Publication Date 2003-04-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1520-6106;1520-5207; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.177 Times cited 9 Open Access
Notes Approved Most recent IF: 3.177; 2003 IF: 3.679
Call Number UA @ lucian @ c:irua:103300 Serial 24
Permanent link to this record
 
 
Author Papp, G.; Peeters, F.M.
Title Strong wave-vector filtering and nearly 100% spin polarization through resonant tunneling antisymmetrical magnetic structure (vol 81, pg 691, 2002) Type L1 Letter to the editor
Year 2003 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 82 Issue 20 Pages 3570-3570
Keywords L1 Letter to the editor; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000182823300065 Publication Date 2003-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 21 Open Access
Notes Approved Most recent IF: 3.411; 2003 IF: 4.049
Call Number UA @ lucian @ c:irua:103295 Serial 3185
Permanent link to this record
 
 
Author Yu, M.Y.; Yu, W.; Chen, Z.Y.; Zhang, J.; Yin, Y.; Cao, L.H.; Lu, P.X.; Xu, Z.Z.
Title Electron acceleration by an intense short-pulse laser in underdense plasma Type A1 Journal article
Year 2003 Publication Physics of plasmas Abbreviated Journal Phys Plasmas
Volume 10 Issue 6 Pages 2468-2474
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Electron acceleration from the interaction of an intense short-pulse laser with low density plasma is considered. The relation between direct electron acceleration within the laser pulse and that in the wake is investigated analytically. The magnitude and location of the ponderomotive-force-caused charge separation field with respect to that of the pulse determine the relative effectiveness of the two acceleration mechanisms. It is shown that there is an optimum condition for acceleration in the wake. Electron acceleration within the pulse dominates as the pulse becomes sufficiently short, and the latter directly drives and even traps the electrons. The latter can reach ultrahigh energies and can be extracted by impinging the pulse on a solid target. (C) 2003 American Institute of Physics.
Address
Corporate Author Thesis
Publisher Place of Publication Woodbury, N.Y. Editor
Language Wos 000183316500031 Publication Date 2003-05-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1070-664X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.115 Times cited 41 Open Access
Notes Approved Most recent IF: 2.115; 2003 IF: 2.146
Call Number UA @ lucian @ c:irua:103293 Serial 904
Permanent link to this record
 
 
Author Bals, S.; Van Tendeloo, G.; Rijnders, G.; Huijben, M.; Leca, V.; Blank, D.H.A.
Title Transmission electron microscopy on interface engineered superconducting thin films Type A1 Journal article
Year 2003 Publication IEEE transactions on applied superconductivity Abbreviated Journal Ieee T Appl Supercon
Volume 13 Issue 2:3 Pages 2834-2837
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Transmission electron microscopy is used to evaluate different deposition techniques, which optimize the microstructure and physical properties of superconducting thin films. High-resolution electron microscopy proves that the use of an YBa2Cu2Ox buffer layer can avoid a variable interface configuration in YBa2Cu3O7-delta thin films grown on SrTiO3. The growth can also be controlled at an atomic level by, using sub-unit cell layer epitaxy, which results in films with high quality and few structural defects. Epitaxial strain in Sr0.85La0.15CuO2 infinite layer thin films influences the critical temperature of these films, as well as the microstructure. Compressive stress is released by a modulated or a twinned microstructure, which eliminates superconductivity. On the other hand, also tensile strain seems to lower the critical temperature of the infinite layer.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000184242400101 Publication Date 2003-07-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 13 Open Access
Notes Iuap V-1; Fwo Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103292 Serial 3712
Permanent link to this record
 
 
Author Lazoryak, B.I.; Baryshnikova, O.V.; Stefanovich, S.Y.; Malakho, A.P.; Morozov, V.A.; Belik, A.A.; Leonidov, I.A.; Leonidova, O.N.; Van Tendeloo, G.
Title Ferroelectric and ionic-conductive properties of nonlinear-optical vanadate, Ca9Bi(VO4)7 Type A1 Journal article
Year 2003 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 15 Issue 15 Pages 3003-3010
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Structural, chemical, and physical properties of whitlockite-type Ca9Bi(VO4)(7) were studied by X-ray powder diffraction (XRD), electron diffraction (ED), second-harmonic generation (SHG), thermogravimetry, differential scanning calorimetry, dielectric, and electrical-conductivity measurements. A new phase-transition of the ferroelectric type was found in Ca9Bi(VO4)(7) with a transition temperature, T-c of 1053 +/- 3 K. The polar phase, beta-Ca9Bi(VO4)(7), is stable below T-c down to at least 160 K. The centrosymmetric beta'-phase is stable above T-c up to 1273 +/- 5 K. Above 1273 K, it decomposes to give BiVO4 and whitlockite-type solid solutions of Ca9+1.5xBi1-x(VO4)(7). The beta<---->beta' phase transition is reversible and of second order. Electrical conductivity of beta'-Ca9Bi(VO4)(7) is rather high (sigma = 0.6 x 10(-3) S/cm at 1200 K) and obeys the Arrhenius law with an activation energy of 1.0 eV. Structure parameters of Ca9Bi(VO4)(7) are refined by the Rietveld method from XRD data measured at room temperature (space group R3c; Z = 6; a = 10.8992(1) Angstrom, c = 38.1192(4) Angstrom, and V = 3921.6(1) Angstrom(3); R-wp = 3.06% and R-p = 2.36%). Bi3+ ions together with Ca2+ ions are statistically distributed among the M1, M2, M3, and M5 sites. Ca9Bi(VO4)(7) has a SHG efficiency of about 140 times that of quartz. Through the powder SHG measurements, we estimated the nonlinear optical susceptibility, Digital, at about 6.1-7.2 pm/V. This value for Ca9Bi(VO4)(7) is comparable with that for known nonlinear optical materials such as LiNbO3 and LiTaO3.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000184379900024 Publication Date 2003-07-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 51 Open Access
Notes Iup V-1; Dwtc Approved Most recent IF: 9.466; 2003 IF: 4.374
Call Number UA @ lucian @ c:irua:103284 Serial 1179
Permanent link to this record
 
 
Author Ball, J.M.; Schryvers, D.
Title The analysis of macrotwins in NiAl martensite Type A1 Journal article
Year 2003 Publication Journal de physique: 4 T2 – 10th International Conference on Martensitic Transformations, JUN 10-14, 2002, ESPOO, FINLAND Abbreviated Journal J Phys Iv
Volume 112 Issue Part 1 Pages 159-162
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We present a theoretical study of macrotwins arising in cubic to tetragonal martensitic transformations. The results help to explain some features of such macrotwins observed in Ni65Al35.
Address
Corporate Author Thesis
Publisher Place of Publication Les Ulis Editor
Language Wos 000186503200024 Publication Date 2008-08-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1155-4339; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 11 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103275 Serial 3569
Permanent link to this record
 
 
Author Linssen, T.; Cassiers, K.; Cool, P.; Lebedev, O.; Whittaker, A.; Vansant, E.F.
Title Physicochemical and structural characterization of mesoporous aluminosilicates synthesized from leached saponite with additional aluminum incorporation Type A1 Journal article
Year 2003 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 15 Issue 25 Pages 4863-4873
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Abstract A thorough investigation was performed on the physical (mechanical, thermal, and hydrothermal stability) and chemical (ion exchange capacity and silanol number) characteristics of aluminosilicate FSMs, synthesized via a new successful short-time synthesis route using leached saponite and a low concentration of CTAB. Moreover, the influence of an additional Al incorporation, utilizing different aluminum sources, on the structure of the FSM derived from saponite is studied. A mesoporous aluminosilicate with a low Si/Al ratio of 12.8 is synthesized, and still has a very large surface area of 1130 m(2)/g and pore volume of 0.92 cm(3)/g. The aluminum-containing samples all have a high cation exchange capacity of around 1 mmol/9 while they still have a silanol number of about 0.9 OH/nm(2); both characteristics being interesting for high-yield postsynthesis modification reactions. Finally, a study is performed on the transformation of the aluminosilicates into their Bronsted acid form via the exchange with ammonium ions and a consecutive heat treatment.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000187250800026 Publication Date 2003-12-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 11 Open Access
Notes Approved Most recent IF: 9.466; 2003 IF: 4.374
Call Number UA @ lucian @ c:irua:103265 Serial 2618
Permanent link to this record
 
 
Author Verberck, B.; Nikolaev, A.V.; Michel, K.H.
Title Theoretical model for the structural phase transition and the metal-insulator transition in polymerized KC60 Type A1 Journal article
Year 2004 Publication Fullerenes, nanotubes, and carbon nanostructures T2 – 6th Biennial International Workshop on Fullerenes and Atomic Clusters, JUN 30-JUL 04, 2003, St Petersburg, RUSSIA Abbreviated Journal Fuller Nanotub Car N
Volume 12 Issue 1-2 Pages 243-252
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The recently discovered structural phase transition in Polymerized KC60 at about 50K leads to a doubling of the unit cell volume and is accompanied by a metal-insulator transition. Here, we show that the ((a) over right arrow + (c) over right arrow, (b) over right arrow, (a) over right arrow – (c) over right arrow) superstructure results from orientational charge density waves along the polymer chains and correlated displacements of the K+ ions. The presented model can also account for the metal-insulator transition. The effect is specific for the space group Pmnn of KC60 and is absent in both Rb- and CsC60 (space group 12/m), in agreement with the present experimental knowledge of these compounds.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000220551600040 Publication Date 2004-03-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1536-383X;1536-4046; ISBN Additional Links (down) UA library record; WoS full record
Impact Factor 1.35 Times cited Open Access
Notes Approved Most recent IF: 1.35; 2004 IF: 1.117
Call Number UA @ lucian @ c:irua:103259 Serial 3607
Permanent link to this record
 
 
Author Papp, G.; Peeters, F.M.
Title Comment on “Tunable spin-injection and magnetoconductance in a novel 2DEG-ferromagnet structure” [phys. stat. sol. (b) 235, No. 1, 157-161 (2003)] Type A1 Journal article
Year 2004 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B
Volume 241 Issue 1 Pages 222-223
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We point out that the predicted strong spin-injection effect by Jiang and Jalil [phys. stat. sol. (b) 235, 157 (2003)] for a double magnetic barrier structure is based on a wrong calculation of the transmission probability. We corrected the result and found no significant spin-injection.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000188585200028 Publication Date 2003-12-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1972;1521-3951; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.674 Times cited 11 Open Access
Notes Approved Most recent IF: 1.674; 2004 IF: 0.982
Call Number UA @ lucian @ c:irua:103257 Serial 413
Permanent link to this record
 
 
Author Laffez, P.; Lebedev, O.I.; Ruello, P.; Desfeux, R.; Banerjee, G.; Capon, F.
Title Evidence of strain induced structural change in hetero-epitaxial NdNiO3 thin films with metal-insulator transition Type A1 Journal article
Year 2004 Publication European physical journal: applied physics Abbreviated Journal Eur Phys J-Appl Phys
Volume 25 Issue 1 Pages 25-31
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Neodymium nickelate thin films have been prepared on NdGaO3 substrates by RF magnetron sputtering and post-annealing treatment under oxygen pressure. Transport properties are found to depend strongly on film thickness. Thick films show transport properties close to bulk ceramics, while very thin films exhibit a large transition from metal to insulator which occurs over a wide temperature range with high resistivity. Structure and surface morphology of the films have been investigated by Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). Thin films (approximate to17 nm) grow heteroepitaxially, while thicker films (approximate to73 nm) show a granular structure. The thinnest sample suggests a symmetry change induced by the epitaxial strain of the substrate. This paper discusses the relationship between microstructure and transport properties.
Address
Corporate Author Thesis
Publisher Place of Publication Paris Editor
Language Wos 000187286000003 Publication Date 2003-12-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1286-0042;1286-0050; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 0.684 Times cited 12 Open Access
Notes Approved Most recent IF: 0.684; 2004 IF: 0.745
Call Number UA @ lucian @ c:irua:103256 Serial 1096
Permanent link to this record
 
 
Author Kirschhock, C.E.A.; Liang, D.; Aerts, A.; Aerts, C.A.; Kremer, S.P.B.; Jacobs, P.A.; Van Tendeloo, G.; Martens, J.A.
Title On the TEM and AFM evidence of zeosil nanoslabs present during the synthesis of silicalite-1 : reply Type L1 Letter to the editor
Year 2004 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 43 Issue 35 Pages 4562-4564
Keywords L1 Letter to the editor; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000224008400003 Publication Date 2004-08-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851;1521-3773; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited Open Access
Notes Fwo; Iap-Pai Approved Most recent IF: 11.994; 2004 IF: 9.161
Call Number UA @ lucian @ c:irua:103253 Serial 2457
Permanent link to this record
 
 
Author Szafran, B.; Bednarek, S.; Adamowski, J.; Tavernier, M.B.; Anisimovas, E.; Peeters, F.M.
Title Accuracy of the Hartree-Fock method for Wigner molecules at high magnetic fields Type A1 Journal article
Year 2004 Publication European physical journal : D : atomic, molecular and optical physics Abbreviated Journal Eur Phys J D
Volume 28 Issue 3 Pages 373-380
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Few-electron systems confined in two-dimensional parabolic quantum dots at high magnetic fields are studied by the Hartree-Fock (HF) and exact diagoiialization methods. A generalized multicenter Gaussian basis is proposed in the HF method. A comparison of the HF and exact, results allows as to discuss the relevance of the symmetry of the charge density distribution for the accuracy of the HF method. It is shown that the energy estimates obtained with the broken-symmetry HF wave functions become exact in the infinite magnetic-field limit. In this limit the charge density of the broken-symmetry solution call be identified with the classical charge distribution.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000220378400008 Publication Date 2004-03-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6060;1434-6079; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.288 Times cited 14 Open Access
Notes Approved Most recent IF: 1.288; 2004 IF: 1.692
Call Number UA @ lucian @ c:irua:103246 Serial 43
Permanent link to this record
 
 
Author Shanenko, A.A.; Ivanov, V.A.
Title Effects of confining interaction in meso-superconductors Type A1 Journal article
Year 2004 Publication Physics letters : A Abbreviated Journal Phys Lett A
Volume 322 Issue 5-6 Pages 384-389
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract This Letter presents a generalized Ginzburg-Landau equation for the superconducting order parameter which includes the terms resulting from the confining interaction associated with the specimen boundary. While the original Ginzburg-Landau theory had been developed for a bulk superconductor, this generalization is meant for study of a meso-superconductor. (C) 2004 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000220123600018 Publication Date 2004-02-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0375-9601; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.772 Times cited 1 Open Access
Notes Approved Most recent IF: 1.772; 2004 IF: 1.454
Call Number UA @ lucian @ c:irua:103244 Serial 859
Permanent link to this record
 
 
Author Fleurov, V.; Kikoin, K.; Ivanov, V.A.; Krstajic, P.M.; Peeters, F.M.
Title Mechanisms of double magnetic exchange in dilute magnetic semiconductors Type A1 Journal article
Year 2004 Publication Journal of magnetism and magnetic materials T2 – International Conference on Magnetism (ICM 2003), JUL 27-AUG 01, 2003, Rome, ITALY Abbreviated Journal J Magn Magn Mater
Volume 272 Issue Part 3 Pages 1967-1968
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A microscopic Hamiltonian for interacting manganese impurities in dilute magnetic semiconductors (DMS) is derived. It is shown that in p-type III-V DMS, the indirect exchange between Mn impurities has similarities with the Zener mechanism in transition metal oxides. Here the mobile and localized holes near the top of the valence band play the role of unoccupied p-orbitals which induce ferromagnetism. T-C estimated from the proposed kinematic exchange agrees with experiments on (Ga,Mn)As. The model is also applicable to the p-doped (Ga,Mn)P system. The magnetic ordering in n-type (Ga,Mn)N is due to exchange between the electrons localized on the levels lying deep in the forbidden energy gap. This mechanism is even closer to the original Zener mechanism. (C) 2003 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000222236800142 Publication Date 2004-01-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-8853; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.63 Times cited 12 Open Access
Notes Approved Most recent IF: 2.63; 2004 IF: 1.031
Call Number UA @ lucian @ c:irua:103233 Serial 1981
Permanent link to this record
 
 
Author Filinov, A.V.; Peeters, F.M.; Riva, C.; Lozovik, Y.E.; Bonitz, M.
Title Exciton molecules in quantum wells : influence of the well width fluctuations Type A1 Journal article
Year 2004 Publication Few-body systems T2 – 3rd International Workshop on Dynamics and Structure of Critically, Stable Quantum Few-Body Systems, SEP 01-05, 2003, Trento, ITALY Abbreviated Journal Few-Body Syst
Volume 34 Issue 1-3 Pages 149-154
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The influence of the well width fluctuations on the dependence of the binding energy of excitonic complexes in quantum wells is studied by using the path-integral Monte-Carlo technique. The results are compared with available experimental data and a good agreement is found.
Address
Corporate Author Thesis
Publisher Place of Publication Wien Editor
Language Wos 000222009500025 Publication Date 2004-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0177-7963;1432-5411; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 0.877 Times cited 2 Open Access
Notes Approved Most recent IF: 0.877; 2004 IF: 1.948
Call Number UA @ lucian @ c:irua:103232 Serial 1113
Permanent link to this record
 
 
Author Szafran, B.; Peeters, F.M.
Title Re-entrant pinning of Wigner molecules in a magnetic field due to a Coulomb impurity Type A1 Journal article
Year 2004 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett
Volume 66 Issue 5 Pages 701-707
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Pinning of magnetic-field-induced Wigner molecules (WMs) confined in parabolic two-dimensional quantum dots by a charged defect is studied by an exact diagonalization approach. We found a re-entrant pinning of the WMs as a function of the magnetic field, a magnetic-field-induced re-orientation of the WMs and a qualitatively different pinning behaviour in the presence of a positive and negative Coulomb impurity.
Address
Corporate Author Thesis
Publisher Place of Publication Paris Editor
Language Wos 000223064900014 Publication Date 2004-05-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0295-5075;1286-4854; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.957 Times cited 11 Open Access
Notes Approved Most recent IF: 1.957; 2004 IF: 2.120
Call Number UA @ lucian @ c:irua:103226 Serial 2816
Permanent link to this record
 
 
Author Wang, X.F.; Vasilopoulos, P.; Peeters, F.M.
Title Influence of spin-orbit interaction on the magnetotransport of a periodically modulated two-dimensional electron gas Type A1 Journal article
Year 2004 Publication International journal of modern physics: B: condensed matter physics, statistical physics, applied physics T2 – 16th International Conference on High Magnetic Fields in Semiconductor, Physics, AUG 02-06, 2004, Florida State Univ, NHMFL, Tallahassee, FL Abbreviated Journal Int J Mod Phys B
Volume 18 Issue 27-29 Pages 3653-3656
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Transport properties of a two-dimensional electron gas (2DEG) are studied in the presence of a normal magnetic field B, of a weak one-dimensional (1D) periodic potential modulation V(x) = V(0)cos(Kx), and of the Rashba spin-orbit interaction (SOI) of strength a. For V(x) = 0 the SOI mixes the up and down spin states of neighboring Landau levels into two, unequally spaced energy branches. For V(x) not equal 0 these levels broaden into bands and their bandwidths oscillate with B. The n-th level bandwidth of each series vanishes at different values of B. Relative to the ID-modulated 2DEG without SOI and one flat-band condition, there are two flat-band conditions that depend on a and the transport coefficients can change considerably. For weak a the Weiss oscillations show beating patterns while for strong a the Shubnikov-de Haas ones axe split in two.
Address
Corporate Author Thesis
Publisher Place of Publication Singapore Editor
Language Wos 000227140200040 Publication Date 2005-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0217-9792;1793-6578; ISBN Additional Links (down) UA library record; WoS full record
Impact Factor 0.736 Times cited Open Access
Notes Approved Most recent IF: 0.736; 2004 IF: 0.361
Call Number UA @ lucian @ c:irua:103199 Serial 1633
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Author Shanenko, A.A.
Title Imperfect fermi gas : kinetic and interaction energies Type A1 Journal article
Year 2004 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
Volume 70 Issue 6 Pages 063618-13
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A uniform ground-state three-dimensional Fermi gas with short-range repulsive pairwise interaction is under consideration. Its kinetic and interaction energies are calculated up to the second order of the expansion in the gas parameter. Similar to recent results for an interacting Bose gas, the quantities in question are found to depend on the pairwise interaction through two characteristic lengths: the former, a, is the s-wave scattering length, and the latter, b, is related to a by b=a-m(partial derivativea/partial derivativem), where m stands for the fermion mass. To control the results, we proceed in two independent ways. The first involves the Hellmann-Feynman theorem applied to derive the kinetic and interaction energies from the total-energy expansion in the gas parameter first found by Huang and Yang. The second way operates with in-medium pair wave functions and allows one to calculate the quantities of interest “from scratch.” The results of the present investigation, taken together with those of the recent consideration of a dilute Bose gas, make it possible to conclude that the pairwise interaction in a quantum gas has an essential and nontrivial effect on the kinetic energy, which is not the case for a classical many-particle system.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000226418900116 Publication Date 2004-12-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1050-2947;1094-1622; ISBN Additional Links (down) UA library record; WoS full record
Impact Factor 2.925 Times cited Open Access
Notes Approved Most recent IF: 2.925; 2004 IF: 2.902
Call Number UA @ lucian @ c:irua:103196 Serial 1562
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Author Szafran, B.; Peeters, F.M.; Bednarek, S.; Adamowski, J.
Title Exact broken-symmetry states and Hartree-Fock solutions for quantum dots at high magnetic fields Type A1 Journal article
Year 2005 Publication Physica. E: Low-dimensional systems and nanostructures T2 – 3rd International Conference on Quantum Dots (QD 2004), MAY 10-13, 2004, Max Bell Bldg Banff Ctr, Banff, Canada Abbreviated Journal Physica E
Volume 26 Issue 1-4 Pages 252-256
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Wigner molecules formed at high magnetic fields in circular and elliptic quantum dots are studied by exact diagonalization (ED) and unrestricted Hartree-Fock (UHF) methods with multicenter basis of displaced lowest Landau level wave functions. The broken symmetry states with semi-classical charge density constructed from superpositions of the ED solutions are compared to the UHF results. UHF overlooks the dependence of the few-electron wave functions on the actual relative positions of electrons localized in different charge puddles and partially compensates for this neglect by an exaggerated separation of charge islands which are more strongly localized than in the exact broken-symmetry states. (C) 2004 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000227249000053 Publication Date 2004-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.221 Times cited 2 Open Access
Notes Approved Most recent IF: 2.221; 2005 IF: 0.946
Call Number UA @ lucian @ c:irua:103181 Serial 1105
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Author Tadić, M.; Mlinar, V.; Peeters, F.M.
Title Multiband k\cdot p calculation of exciton diamagnetic shift in InP/InGaP self-assembled quantum dots Type A1 Journal article
Year 2005 Publication Physica. E: Low-dimensional systems and nanostructures T2 – 3rd International Conference on Quantum Dots (QD 2004), MAY 10-13, 2004, Max Bell Bldg Banff Ctr, Banff, Canada Abbreviated Journal Physica E
Volume 26 Issue 1-4 Pages 212-216
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Exciton states in self-assembled InP/In0.49Ga0.51P quantum dots subject to magnetic fields up to 50T are calculated. Strain and band mixing are explicitly taken into account in the single-particle models of the electronic structure, while an exact diagonalization approach is adopted to compute the exciton states. Reasonably good agreement with magneto-photoluminescence measurements on InP self-assembled quantum dots is found. As a result of the polarization and angular momentum sensitive selection rules, the exciton ground state is dark. For in-plane polarized light, the magnetic field barely affects the exciton spatial localization, and consequently the exciton oscillator strength for recombination increases only slightly with increasing field. For z polarized light, a sharp increase of the oscillator strength beyond 30 T is found which is attributed to the enhanced s character of the relevant portion of the exciton wave function. (C) 2004 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000227249000045 Publication Date 2004-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.221 Times cited 4 Open Access
Notes Approved Most recent IF: 2.221; 2005 IF: 0.946
Call Number UA @ lucian @ c:irua:103180 Serial 2215
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Author Yang, W.; Chang, K.; Peeters, F.M.
Title Spin-polarized transport of two-dimensional electron gas embedded in a diluted magnetic semiconductor Type A1 Journal article
Year 2005 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 86 Issue 19 Pages 192107-3
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The spin-polarized transport property of a diluted magnetic semiconductor two-dimensional electron gas is investigated theoretically at low temperature. A large current polarization can be found in this system even at small magnetic fields and oscillates with increasing magnetic field while the carrier polarization is vanishingly small. The magnitude as well as the sign of the current polarization can be tuned by varying magnetic field, the electron density and the Mn concentration. (c) 2005 American Institute of Physics.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000229397900042 Publication Date 2005-05-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 10 Open Access
Notes Approved Most recent IF: 3.411; 2005 IF: 4.127
Call Number UA @ lucian @ c:irua:103163 Serial 3097
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Author Fang, P.a.; Gu, H.; Wang, P.l.; Van Landuyt, J.; Vleugels, J.; Van der Biest, O.;
Title Effect of powder coating on stabilizer distribution in CeO2-stabilized ZrO2 ceramics Type A1 Journal article
Year 2005 Publication Journal of the American Ceramic Society Abbreviated Journal J Am Ceram Soc
Volume 88 Issue 7 Pages 1929-1934
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The phase and microstructure relationship of 12 mol% CeO2-stabilized ZrO2 ceramics prepared from coated powder was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersed Xray spectroscopy (EDS). As compared with the sample prepared with co-precipitated method, which exhibited a similar grain size distribution, the EDS analysis revealed that the powder coating induced a wide distribution of CeO2 solubility, which decreases monotonically with the increase of grain size. This variation of stabilizer content from grain to grain rendered many large grains in the monoclinic phase. Stronger cerium segregation to grain boundaries was observed between large grains, which often form thin amorphous films there. The inhomogeneous; CeO2 distribution keeps more tetragonal ZrO2 grains close to the phase boundary to facilitate the transforming toughness. Addition of an Al2O3 precursor in coated powders effectively raises the overall CeO2 stabilizer content in the grains and preserves more transformable tetragonal phase in the microstructure, which further enhanced the fracture toughness. The dependence of CeO2 solubility on grain size may be explained in a simple coating-controlled diffusion and growth process that deserves further investigation.
Address
Corporate Author Thesis
Publisher Place of Publication Columbus, Ohio Editor
Language Wos 000230128100040 Publication Date 2005-06-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7820;1551-2916; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.841 Times cited 11 Open Access
Notes Approved Most recent IF: 2.841; 2005 IF: 1.586
Call Number UA @ lucian @ c:irua:103156 Serial 830
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Author Ferreira, W.P.; Munarin, F.F.; Nelissen, K.; Costa, R.N.; Peeters, F.M.; Farias, G.A.
Title Structure, normal mode spectra, and mixing of a binary system of charged particles confined in a parabolic trap Type A1 Journal article
Year 2005 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 72 Issue 2 Part 1 Pages 021406-21413
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the mixing of two different kinds of particles, having different charge and/or mass, interacting through a pure Coulomb potential, and confined in a parabolic trap. The structure of the cluster and its normal mode spectrum are analyzed as a function of the ratio of the charges (mass ratio) of the two types of particles. We show that particles are not always arranged in a shell structure. Mixing of the particles goes hand in hand with a large number of metastable states. The normal modes of the system are obtained, and we find that some of the special modes can be tuned by varying the ratio between the charges (masses) of the two species. The degree of mixing of the two type of particles is summarized in a phase diagram, and an order parameter that describes quantitatively the mixing between particles is defined.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000231564000031 Publication Date 2005-08-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 25 Open Access
Notes Approved Most recent IF: 2.366; 2005 IF: 2.418
Call Number UA @ lucian @ c:irua:103149 Serial 3306
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Author Berdiyorov, G.R.; Cabral, L.R.E.; Peeters, F.M.
Title Surface barrier for flux entry and exit in mesoscopic superconducting systems Type A1 Journal article
Year 2005 Publication Journal of mathematical physics Abbreviated Journal J Math Phys
Volume 46 Issue 9 Pages 095105
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The energy barrier which has to be overcome for a single vortex to enter or exit the sample is studied for thin superconducting disks, rings, and squares using the nonlinear Ginzburg-Landau theory. The shape and the height of the nucleation barrier is investigated for different sample radii and thicknesses and for different values of the Ginzburg-Landau parameter kappa. It is shown that the London theory considerably overestimates (underestimates) the energy barrier for vortex expulsion (penetration). (c) 2005 American Institute of Physics.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000232206700005 Publication Date 2005-09-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2488; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.077 Times cited 18 Open Access
Notes Approved Most recent IF: 1.077; 2005 IF: 1.192
Call Number UA @ lucian @ c:irua:103142 Serial 3393
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Author Axt, V.M.; Kuhn, T.; Vagov, A.; Peeters, F.M.
Title Phonon-induced pure dephasing in exciton-biexciton quantum dot systems driven by ultrafast laser pulse sequences 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 125309-125315
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A semiconductor quantum dot model accounting for single exciton as well as biexciton states coupled to phonons and laser light is investigated in the limit of strong electronic confinement. For an arbitrary sequence of excitations with ultrafast pulses analytical solutions are obtained for all density-matrix elements. The results are nonperturbative with respect to both the carrier-phonon and the carrier-light coupling. Numerical results for a single pulse excitation are presented illustrating spectral features of our solution as well as pulse area and temperature dependences.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000232229400075 Publication Date 2005-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 48 Open Access
Notes Approved Most recent IF: 3.836; 2005 IF: 3.185
Call Number UA @ lucian @ c:irua:103139 Serial 2604
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Author Mueller, G.; Stahnke, F.; Bleiner, D.
Title Fast steel-cleanness characterization by means of laser-assisted plasma spectrometric methods Type A1 Journal article
Year 2006 Publication Talanta : the international journal of pure and applied analytical chemistry T2 – 34th Colloquium Spectroscopicum Internationale, SEP 04-09, 2005, Univ Antwerp, Antwerp, BELGIUM Abbreviated Journal Talanta
Volume Issue Pages
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Laser-assisted plasma spectrometry is a palette of analytical techniques (L-OES, LA-ICP-MS) capable of fast spatially-resolved elemental analysis in the micrometer range. For fast estimation of the occurrence in steel samples of non-metallic inclusions, which degrade the material's technical properties, simultaneous OES detection and sequential ICP-MS detection were compared. Histograms were obtained for the intensity distribution of the acquired signals (laser pulse statistics). The skewness coefficient of the histograms for Al (indicator of non-metallic inclusions) was found to be clearly dependent on the fraction of non-metallic inclusions in the case of scanning L-OES. For LA-ICP-MS less clear dependence was observed, which was influenced by the acquisition characteristics. In fact, less measurement throughput limited for LA-ICP-MS the counting statistics to an extent that overrides the benefit of higher detection power as compared to L-OES. (c) 2006 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Pergamon Place of Publication Oxford Editor
Language Wos 000242871900015 Publication Date 2006-07-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-9140; 1873-3573 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 4.162 Times cited 12 Open Access
Notes Approved Most recent IF: 4.162; 2006 IF: 2.810
Call Number UA @ lucian @ c:irua:103122 Serial 4518
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Author Bencs, L.
Title Calculation of the spectral line profile broadening parameter in graphite furnace atomic absorption spectrometry Type A1 Journal article
Year 2008 Publication Canadian Journal Of Analytical Sciences And Spectroscopy Abbreviated Journal
Volume 53 Issue 2 Pages 52-58
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract A polynomial approach is applied for a number of data from the Posener-tables to calculate the values of the intensity distribution function of atomic absorption lines – H(a, 0.726a) – at the tabulated damping-parameter values with an error not worse than 0.044 %. For the resultant H(a, 0.726a) data, the ninth and sixth order polynomials can be fitted according to the damping parameter range of 0-2, and 2-10, respectively, which results in a minimal error of approximation. The derived functions are simply applicable to the calculation of any H(a, 0.726a) value belonging to a damping-parameter of any arbitrarily selected spectral line, implying the influence of Doppler- and Lorentz-broadening. The overall error of the described method is lower than 0.4 %.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000260130600002 Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1205-6685 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:103094 Serial 7571
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Author Lin, K.; Pescarmona, P.P.; Vandepitte, H.; Liang, D.; Van Tendeloo, G.; Jacobs, P.A.
Title Synthesis and catalytic activity of Ti-MCM-41 nanoparticles with highly active titanium sites Type A1 Journal article
Year 2008 Publication Journal of catalysis Abbreviated Journal J Catal
Volume 254 Issue 1 Pages 64-70
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ti-MCM-41 nanoparticles 80-160 nm in diameter (Ti-MCM-41 NP) were successfully prepared by a dilute solution route in sodium hydroxide medium at ambient temperature. Ti-MCM-41 NP were characterized by X-ray diffraction, nitrogen adsorption/desorption isotherms, SEM, TEM. FT-IR, and UV-vis spectroscopy. The characterization results showed the existence of highly ordered hexagonal mesoporous structure and tetrahedral Ti species in Ti-MCM-41 NP. In the epoxidation of cyclohexene with aqueous H2O2, Ti-MCM-41 NP displayed higher conversion and initial reaction rate than a Ti-MCM-41 sample with normal particle size (Ti-MCM-41 LP). Diffusion of the reactants was accelerated and the accessibility to the catalytic Ti species was enhanced in the shorter channels in Ti-MCM-41 NP samples. Ti-MCM-41 NP showed much higher selectivity for cyclohexene oxide compared with Ti-MCM-41 LP, suggesting reduced hydrolysis of cyclohexene oxide with water in the former case. The increased selectivity for cyclohexene oxide can be attributed to the lower concentration of residual surface silanols in Ti-MCM-41 NP and the shorter residence time of epoxide in the shorter mesoporous channels. Ti-MCM-41 NP also appears to be a suitable catalyst in the epoxidation of a bulky substrate, like cholesterol, with tert-butyl hydroperoxide. (c) 2007 Elsevier Inc. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication San Diego, Calif. Editor
Language Wos 000253646100006 Publication Date 2008-01-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9517; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 6.844 Times cited 52 Open Access
Notes Approved Most recent IF: 6.844; 2008 IF: 5.167
Call Number UA @ lucian @ c:irua:103092 Serial 3409
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