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Author Batuk, M.; Batuk, D.; Tsirlin, A.A.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.
Title Homologous series of layered perovskites An+1BnO3n-1Cl : crystal and magnetic structure of a new oxychloride Pb4BiFe4O11Cl Type A1 Journal article
Year 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 52 Issue 4 Pages 2208-2218
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The nuclear and magnetic structure of a novel oxychloride Pb4BiFe4O11Cl has been studied over the temperature range 1.5700 K using a combination of transmission electron microscopy and synchrotron and neutron powder diffraction [space group P4/mbm, a = 5.5311(1) Å, c = 19.586(1) Å, T = 300 K]. Pb4BiFe4O11Cl is built of truncated (Pb,Bi)3Fe4O11 quadruple perovskite blocks separated by CsCl-type (Pb,Bi)2Cl slabs. The perovskite blocks consist of two layers of FeO6 octahedra located between two layers of FeO5 tetragonal pyramids. The FeO6 octahedra rotate about the c axis, resulting in a √2ap × √2ap × c superstructure. Below TN = 595(17) K, Pb4BiFe4O11Cl adopts a G-type antiferromagnetic structure with the iron magnetic moments confined to the ab plane. The ordered magnetic moments at 1.5 K are 3.93(3) and 3.62(4) μB on the octahedral and square-pyramidal iron sites, respectively. Pb4BiFe4O11Cl can be considered a member of the perovskite-based An+1BnO3n1Cl homologous series (A = Pb/Bi; B = Fe) with n = 4. The formation of a subsequent member of the series with n = 5 is also demonstrated.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000315255200067 Publication Date 2013-02-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 6 Open Access
Notes Countatoms Approved Most recent IF: 4.857; 2013 IF: 4.794
Call Number (down) UA @ lucian @ c:irua:106185 Serial 1486
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Author He, Z.B.; Deng, G.; Tian, H.; Xu, Q.; Van Tendeloo, G.
Title 90° Rotation of orbital stripes in bilayer manganite PrCa2Mn2O7 studied by in situ transmission electron microscopy Type A1 Journal article
Year 2013 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 200 Issue Pages 287-293
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We present an in situ transmission electron microscopy study on the half-doped bilayer manganite PrCa2Mn2O7 to reveal the rotation process of the orbital stripes. Between the reported initial and final ordering phases, we identified an intermediate state with two sets of satellite spots to bridge the 90° rotation of the orbital stripes. Furthermore, we determined that the rotation of the orbital stripes does not always occur. Some restricted conditions for the orbital rotation to occur were found and reasons are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000317158000043 Publication Date 2013-02-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 5 Open Access
Notes Countatoms Approved Most recent IF: 2.299; 2013 IF: 2.200
Call Number (down) UA @ lucian @ c:irua:106183 Serial 20
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Author Marikutsa, A.; Krivetskiy, V.; Yashina, L.; Rumyantseva, M.; Konstantinova, E.; Ponzoni, A.; Comini, E.; Abakumov, A.; Gaskov, A.
Title Catalytic impact of RuOx clusters to high ammonia sensitivity of tin dioxide Type A1 Journal article
Year 2012 Publication Sensors and actuators : B : chemical T2 – 25th Eurosensors Conference, SEP 04-07, 2011, Athens, GREECE Abbreviated Journal Sensor Actuat B-Chem
Volume 175 Issue Pages 186-193
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A comparative study of NH3-sensing performance of blank and modified nanocrystal line SnO2 was performed. Tin dioxide modified by ruthenium displayed the highest ammonia sensitivity with a maximum signal at 200 degrees C. The modifier was shown by XPS and EPR to occur in a mixed valence state of oxidized ruthenium distributed between the surface and bulk of tin dioxide nanocrystals. RuOx clustering on SnO2 surface was detected by means of electron microscopy assisted EDX-mapping. The effect of RuOx on tin dioxide interaction with ammonia was studied by temperature-programmed NH3 desorption, simultaneous Kelvin probe and DC-resistance measurements, EPR spectroscopy and analyses of the gas-solid interaction products. The modifier was shown to promote the materials reactivity to NH3 due to the catalytic activity of RuOx. The interaction with ammonia resulted in dipoles formation on the oxide surface along with reducing the grains net surface charge, established from the electron affinity increase and resistance decrease during NH3 exposure. The RuOx-catalyzed gas-solid interaction was deduced to proceed deeper than in the case of non-modified SnO2 and to yield nitrogen oxides (e.g. NO2), as was suggested by the oxidative character of gaseous products of NH3 interaction with RuOx-modified tin dioxide at 200 degrees C. (C) 2012 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000312358700033 Publication Date 2012-06-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-4005; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.401 Times cited 20 Open Access
Notes Approved Most recent IF: 5.401; 2012 IF: 3.535
Call Number (down) UA @ lucian @ c:irua:105985 Serial 293
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Author Kalidindi, S.B.; Wiktor, C.; Ramakrishnan, A.; Weßing, J.; Schneemann, A.; Van Tendeloo, G.; Fischer, R.A.
Title Lewis base mediated efficient synthesis and solvation-like host-guest chemistry of covalent organic framework-1 Type A1 Journal article
Year 2013 Publication Chemical communications Abbreviated Journal Chem Commun
Volume 49 Issue 5 Pages 463-465
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract N-Lewis base mediated room temperature synthesis of covalent organic frameworks (COFs) starting from a solution of building blocks instead of partially soluble building blocks was developed. This protocol shifts COF synthetic chemistry from sealed tubes to open beakers. Non-conventional inclusion compounds of COF-1 were obtained by vapor phase infiltration of ferrocene and azobenzene, and solvation like effects were established.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000312193100007 Publication Date 2012-11-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-7345;1364-548X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited 17 Open Access
Notes 262348 Esmi Approved Most recent IF: 6.319; 2013 IF: 6.718
Call Number (down) UA @ lucian @ c:irua:105953 Serial 1815
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Author Hamelet, S.; Casas-Cabanas, M.; Dupont, L.; Davoisne, C.; Tarascon, J.M.; Masquelier, C.
Title Existence of superstructures due to large amounts of Fe vacancies in the LiFePO4-type framework Type A1 Journal article
Year 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 23 Issue 1 Pages 32-38
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract LiFePO4 has been under intense scrutiny over the past decade because it stands as an attractive positive electrode material for the next generation of Li-ion batteries to power electric vehicles and hybrid electric vehicles, hence the importance of its thermal behavior. The reactivity of LiFePO4 with air at moderate temperatures is shown to be dependent on its particle size. For nanosized materials, a progressive displacement of Fe from the core structure leading to a composite made of nanosize Fe2O3 and highly defective, oxidized LixFeyPO4 compositions, among which the “ideal” formula LiFe2/3PO4. Herein we report, from both temperature-controlled X-ray diffraction and electronic diffraction microscopy, that these off-stoichiometry olivine-type compounds show a defect ordering resulting in the formation of a superstructure. Such a finding shows striking similarities with the temperature-driven oxidation of fayalite Fe2SiO4 (another olivine) to structurally defective laihunite, reported in the literature three decades ago.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000285726900007 Publication Date 2010-12-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 30 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number (down) UA @ lucian @ c:irua:105605 Serial 1130
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Author Quintana, M.; Grzelczak, M.; Spyrou, K.; Kooi, B.; Bals, S.; Van Tendeloo, G.; Rudolf, P.; Prato, M.
Title Production of large graphene sheets by exfoliation of graphite under high power ultrasound in the presence of tiopronin Type A1 Journal article
Year 2012 Publication Chemical communications Abbreviated Journal Chem Commun
Volume 48 Issue 100 Pages 12159-12161
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Under ultrasonication, the production of high quality graphene layers by exfoliation of graphite was achieved via addition of tiopronin as an antioxidant.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000311411100003 Publication Date 2012-10-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-7345;1364-548X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.319 Times cited 39 Open Access
Notes This work was financially supported by the University of Trieste, INSTM, Italian Ministry of Education MIUR (cofin Prot. 20085M27SS) and by the "Graphene-based electronics'' research program of the Foundation for Fundamental Research on Matter (FOM). Part of this work was supported by funding from the ERC grant No 246791COUNTATOMS. MQ acknowledges the financial support from CONACyT CB-2011-01-166914 and FAI-UASLP. Approved Most recent IF: 6.319; 2012 IF: 6.378
Call Number (down) UA @ lucian @ c:irua:105230 Serial 2724
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Author Tytgat, T.; Hauchecorne, B.; Abakumov, A.M.; Smits, M.; Verbruggen, S.W.; Lenaerts, S.
Title Photocatalytic process optimisation for ethylene oxidation Type A1 Journal article
Year 2012 Publication Chemical engineering journal Abbreviated Journal Chem Eng J
Volume 209 Issue Pages 494-500
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract When studying photocatalysis it is important to consider, beside the chemical approach, the engineering part related to process optimisation. To achieve this a fixed bed photocatalytic set-up consisting of different catalyst placings, in order to vary catalyst distribution, is studied. The use of a fixed quantity of catalyst placed packed or randomly distributed in the reactor, results in an almost double degradation for the distributed catalyst. Applying this knowledge leads to an improved performance with limited use of catalyst. A reactor only half filled with catalyst leads to higher degradation performance compared to a completely filled reactor. Taking into account this simple process optimisation by better distributing the catalyst a more sustainable photocatalytic air purification process is achieved. (C) 2012 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000311190500058 Publication Date 2012-08-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.216 Times cited 12 Open Access
Notes ; We are grateful for the delivered photocatalyst by Evonik as well as for the PhD grant (T. Tytgat) given by the Institute of Innovation by Science and Technology in Flanders (IWT). ; Approved Most recent IF: 6.216; 2012 IF: 3.473
Call Number (down) UA @ lucian @ c:irua:105185 Serial 2609
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Author Ati, M.; Sathiya, M.; Boulineau, S.; Reynaud, M.; Abakumov, A.; Rousse, G.; Melot, B.; Van Tendeloo, G.; Tarascon, J.-M.
Title Understanding and promoting the rapid preparation of the triplite-phase of LiFeSO4F for use as a large-potential Fe cathode Type A1 Journal article
Year 2012 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
Volume 134 Issue 44 Pages 18380-18387
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The development of new electrode materials, which are composed of Earth-abundant elements and that can be made via eco-efficient processes, is becoming absolutely necessary for reasons of sustainable production. The 3.9 V triplite-phase of LiFeSO4F, compared to the 3.6 V tavorite-phase, could satisfy this requirement provided the currently complex synthetic pathway can be simplified. Here, we present our work aiming at better understanding the reaction mechanism that govern its formation as a way to optimize its preparation. We first demonstrate, using complementary X-ray diffraction and transmission electron microscopy studies, that triplite-LiFeSO4F can nucleate from tavorite-LiFeSO4F via a reconstructive process whose kinetics are significantly influenced by moisture and particle morphology. Perhaps the most spectacular finding is that it is possible to prepare electrochemically active triplite-LiFeSO4F from anhydrous precursors using either reactive spark plasma sintering (SPS) synthesis in a mere 20 min at 320 degrees C or room temperature ball milling for 3 h. These new pathways appear to be strongly driven by the easy formation of a disordered phase with higher entropy, as both techniques trigger disorder via rapid annealing steps or defect creation. Although a huge number of phases adopts the tavorite structure-type, this new finding offers both a potential way to prepare new compositions in the triplite structure and a wealth of opportunities for the synthesis of new materials which could benefit many domains beyond energy storage.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000310720900041 Publication Date 2012-10-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0002-7863;1520-5126; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.858 Times cited 36 Open Access
Notes Approved Most recent IF: 13.858; 2012 IF: 10.677
Call Number (down) UA @ lucian @ c:irua:105147 Serial 3802
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Author Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Hadermann, J.; Hodges, J.P.; Herber, R.H.; Nowik, I.; Greenblatt, M.;
Title Magnetic and structural studies of the multifunctional material SrFe0.75Mo0.25O3-\text{\textgreek{d}} Type A1 Journal article
Year 2012 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
Volume 51 Issue 22 Pages 12273-12280
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract SrFe0.75Mo0.25O3-delta has been recently discovered as an extremely efficient electrode for intermediate temperature solid oxide fuel cells (IT-SOFCs). We have performed structural and magnetic studies to fully characterize this multifunctional material. We have observed by powder neutron diffraction (PND) and transmission electron microscopy (TEM) that its crystal symmetry is better explained with a tetragonal symmetry (I4/mcm space group) than with the previously reported orthorhombic symmetry (Pnma space group). The temperature dependent magnetic properties indicate an exceptionally high magnetic ordering temperature (T-N similar to 750 K), well above room temperature. The ordered magnetic structure at low temperature was determined by PND to be an antiferromagnetic coupling of the Fe cations. Mossbauer spectroscopy corroborated the PND results. A detailed study, with X-ray absorption spectroscopy (XAS), in agreement with the Mossbauer results, confirmed the formal oxidation states of the cations to be mixed valence Fe3+/4+ and Mo6+.
Address
Corporate Author Thesis
Publisher Place of Publication Easton, Pa Editor
Language Wos 000311173700024 Publication Date 2012-10-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.857 Times cited 12 Open Access
Notes Approved Most recent IF: 4.857; 2012 IF: 4.593
Call Number (down) UA @ lucian @ c:irua:105142 Serial 1862
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Author Neyts, E.C.; Bogaerts, A.
Title Combining molecular dynamics with Monte Carlo simulations : implementations and applications Type A1 Journal article
Year 2013 Publication Theoretical chemistry accounts : theory, computation, and modeling Abbreviated Journal Theor Chem Acc
Volume 132 Issue 2 Pages 1320-12
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this contribution, we present an overview of the various techniques for combining atomistic molecular dynamics with Monte Carlo simulations, mainly in the context of condensed matter systems, as well as a brief summary of the main accelerated dynamics techniques. Special attention is given to the force bias Monte Carlo technique and its combination with molecular dynamics, in view of promising recent developments, including a definable timescale. Various examples of the application of combined molecular dynamics / Monte Carlo simulations are given, in order to demonstrate the enhanced simulation efficiency with respect to either pure molecular dynamics or Monte Carlo.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000318294700010 Publication Date 2012-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1432-881X;1432-2234; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.89 Times cited 27 Open Access
Notes Approved Most recent IF: 1.89; 2013 IF: 2.143
Call Number (down) UA @ lucian @ c:irua:104725 Serial 404
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Author Bings, N.H.; Bogaerts, A.; Broekaert, J.A.C.
Title Atomic spectroscopy Type A1 Journal article
Year 2013 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 85 Issue 2 Pages 670-704
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000313668400013 Publication Date 2012-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 29 Open Access
Notes Approved Most recent IF: 6.32; 2013 IF: 5.825
Call Number (down) UA @ lucian @ c:irua:104719 Serial 190
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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 Luhrs, C.C.; Molins, E.; Van Tendeloo, G.; Beltran-Porter, D.; Fuertes, A.
Title Crystal structure of Bi6Sr8-xCa3+xO22(-0.5\leq x\leq1.7): a mixed valence bismuth oxide related to perovskite Type A1 Journal article
Year 1998 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 10 Issue 7 Pages 1875-1881
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of BiSr8-xCa3+xO22 has been determined by single-crystal X-ray diffraction. This phase is the same as Bi9Sr11Ca5Oy that was previously studied by several authors as a secondary phase in the Bi-Sr-Ca-Cu-O system and coexists in thermodynamic equilibrium with the superconductors Bi2Sr2CuO6 and Bi2Sr2CaCu2O8 It crystallizes in the monoclinic space group P2(1)/c, with cell parameters a 11.037(3) Angstrom, b = 5.971(2) Angstrom, c = 19.703(7) Angstrom, beta = 101.46(3)degrees Z = 2. The structure was solved by direct methods and full-matrix least-squares refinement. It is built up by perovskite-related blocks of composition [Sr8-xBi2Ca3+xO16] that intergrow with double rows [Bi4O6] running along b. The perovskite blocks are formed by groups of five octahedra that are shifted from each other 3/2 root 2a(p) along [110](p) (a(p) being the parameter of the cubic perovskite subcell) in a zigzag configuration and are aligned with this direction parallel to the one forming an angle of 25" with the c axis. In turn, the perovskite blocks [Sr8-xBi2Ca3+xO16] are shifted from each other 1/2 of both a(p) and root 2a(p) along [100](p) and [110](p), respectively. In the double rows, two trivalent bismuth atoms are placed, forming dimeric anion complexes [Bi2O6].(6-).6- The oxygen atoms around bismuth in these dimers are placed in the vertexes of a distorted trigonal bipyramid, with one vacant position that would be occupied by the lone pairs characteristic for the electronic configuration of Bi(III). The B sites in the perovskite blocks are occupied by pentavalent bismuth atoms and calcium atoms; the remaining Sr and Ca ions occupy the A sites of the perovskite blocks with coordination numbers with oxygen ranging from 10 to 12. The mean valence for Bi is +3.67 [33.3% of Bi(V) and 66.7% of Bi(III)]. The oxygen vacancies are located in the boundaries between domains having the two possible configurations of the perovskite subcell as in the anionic superconductor Bi3BaO5.5. The oxidation of Bi6Sr8-xCa3+xO22 at 650 degrees C allows the complete filling of the oxygen vacancies to form the double perovskite (Sr2-xCax)Bi1.4Ca0.6O6 that shows 92.5% of bismuth in +5 oxidation state. The experimental high-resolution electon microscopy image and the electron diffraction pattern of powder samples along the [010]* zone axis are in good agreement with those calculated from the structural model obtained by single-crystal X-ray diffraction. The material is almost free of defects and the occurrence of planar defects is very exceptional.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000075019300023 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 6 Open Access
Notes Approved Most recent IF: 9.466; 1998 IF: 3.359
Call Number (down) UA @ lucian @ c:irua:104328 Serial 570
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Author Nikolaev, A.V.; Michel, K.H.
Title Many electron- and hole terms of molecular ions C60n\pm Type A1 Journal article
Year 2003 Publication Coupling In Chemistry And Physics Abbreviated Journal Adv Quantum Chem
Volume 44 Issue Pages 305-312
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000188940800019 Publication Date 2004-05-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0065-3276; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.196 Times cited 1 Open Access
Notes Approved Most recent IF: 1.196; 2003 IF: 0.375
Call Number (down) UA @ lucian @ c:irua:104131 Serial 1942
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Author Colomer, J.F.; Stephan, C.; Lefrant, S.; Van Tendeloo, G.; Willems, I.; Konya, Z.; Fonseca, A.; Laurent, C.; Nagy, J.B.
Title Large-scale synthesis of single-wall carbon nanotubes by catalytic chemical vapor deposition (CCVD) method Type A1 Journal article
Year 2000 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 317 Issue 1-2 Pages 83-89
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The large-scale production of single-wall carbon nanotubes (SWNTs) is reported. Large quantities of SWNTs can be synthesised by catalytic decomposition of methane over well-dispersed metal particles supported on MgO at 1000 degrees C. The thus produced SWNTs can be separated easily from the support by a simple acidic treatment to obtain a product with high yields (70-80%) of SWNTs. Because the typical synthesis time is 10 min, 1 g of SWNTs can be synthesised per day by this method. The SWNTs are characterized by high-resolution transmission electron microscopy and by Raman spectroscopy, showing the quality and the quantity of products. (C) 2000 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000085128300015 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 344 Open Access
Notes Approved Most recent IF: 1.815; 2000 IF: 2.364
Call Number (down) UA @ lucian @ c:irua:103957 Serial 1782
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Author Willems, I.; Konya, Z.; Colomer, J.F.; Van Tendeloo, G.; Nagaraju, N.; Fonseca, A.; Nagy, J.B.
Title Control of the outer diameter of thin carbon nanotubes synthesized by catalytic decomposition of hydrocarbons Type A1 Journal article
Year 2000 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 317 Issue 1-2 Pages 71-76
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Multi-wall carbon nanotubes have been produced by the catalytic decomposition of acetylene. Go-Mo, Co-V and Co-Fe mixtures supported either on zeolite or corundum alumina were used as catalysts. When Fe or V is added to Co, the carbon deposit increases. The nanotubes were characterized by both low and high resolution TEM. From histograms representing the outer diameter distributions, it is clear that the outer diameter of the nanotubes can be controlled by choosing the appropriate catalyst. (C) 2000 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000085128300013 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 130 Open Access
Notes Approved Most recent IF: 1.815; 2000 IF: 2.364
Call Number (down) UA @ lucian @ c:irua:103956 Serial 499
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Author Titantah, J.T.; Pierleoni, C.; Ryckaert, J.-P.
Title Single chain elasticity and thermoelasticity of polyethylene Type A1 Journal article
Year 2002 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 117 Issue 19 Pages 9028-9036
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Single-chain elasticity of polyethylene at theta point up to 90% of stretching with respect to its contour length is computed by Monte Carlo simulation of an atomistic model in continuous space. The elasticity law together with the free-energy and the internal energy variations with stretching are found to be very well represented by the wormlike chain model up to 65% of the chain elongation, provided the persistence length is treated as a temperature-dependent parameter. Beyond this value of elongation simple ideal chain models are not able to describe the Monte Carlo data in a thermodynamic consistent way. This study reinforces the use of the wormlike chain model to interpret experimental data on the elasticity of synthetic polymers in the finite extensibility regime, provided the chain is not yet in its fully stretched regime. Specific solvent effects on the elasticity law and the partition between energetic and entropic contributions to single chain elasticity are investigated. (C) 2002 American Institute of Physics.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000178934700046 Publication Date 2002-10-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 5 Open Access
Notes Approved Most recent IF: 2.965; 2002 IF: 2.998
Call Number (down) UA @ lucian @ c:irua:103862 Serial 3018
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Author de Gryse, O.; Clauws, P.; Vanhellemont, J.; Lebedev, O.I.; van Landuyt, J.; Simoen, E.; Claeys, C.
Title Characterization of oxide precipitates in heavily B-doped silicon by infrared spectroscopy Type A1 Journal article
Year 2004 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 151 Issue 9 Pages G598-G605
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Infrared absorption spectra of oxygen precipitates in boron-doped silicon with a boron concentration between 10(17) and 10(19) cm(-3) are analyzed, applying the spectral function representation of composite materials. The aspect ratio of the platelet precipitates is determined by transmission electron microscopy measurements. The analysis shows that in samples with moderate doping levels (<10(18) B cm(-3)) SiOγ precipitates are formed with the same composition as in the lightly doped case. In the heavily boron-doped (>10(18) cm(-3)) samples, however, the measured spectra of the precipitates are consistent with a mixture of SiO2 and B2O3, with a volume fraction of B2O3 as high as 0.41 in the most heavily doped case. (C) 2004 The Electrochemical Society.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000223622000072 Publication Date 2004-08-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited 13 Open Access
Notes Fwo; Iuap P5/01 Approved Most recent IF: 3.259; 2004 IF: 2.356
Call Number (down) UA @ lucian @ c:irua:103760 Serial 330
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Author Li, Y.; Zhang, X.; Shen, L.; Luo, J.; Tao, X.; Liu, F.; Xu, G.; Wang, Y.; Geise, H.J.; Van Tendeloo, G.
Title Controlling the diameters in large-scale synthesis of single-walled carbon nanotubes by catalytic decomposition of CH4 Type A1 Journal article
Year 2004 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 398 Issue 1-3 Pages 276-282
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High-quality single-walled carbon nanotubes (SWNTs) are synthesized in gram amount on Fe-Mo/MgO catalysts by catalytic decomposition of CH4 in H-2 or N-2. Raman data reveal that the as-prepared SATNTs have a diameter of about 0.74-1.29 nm. It is found that the diameter of the as-prepared SWNTs can be controlled mainly by adjusting the molar ratio of Fe-Mo versus the MgO support. Several other factors that potentially influence the growth of SWNTs have been studied in detail. The experimental results show that the nature of the catalyst determines the diameter of the as-prepared SWNTs. (C) 2004 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000224720300050 Publication Date 2004-10-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2614; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.815 Times cited 45 Open Access
Notes Approved Most recent IF: 1.815; 2004 IF: 2.438
Call Number (down) UA @ lucian @ c:irua:103720 Serial 507
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Author Bussmann-Holder, A.; Dalal, N.; Michel, K.H.
Title Polarizability induced cooperative proton ordering, coexistence of order/disorder and displacive dynamics and isotope effects in hydrogen-bonded systems Type A1 Journal article
Year 2000 Publication The journal of physics and chemistry of solids T2 – Williamsburg Workshop on Ferroelectrics 99, JAN 31-FEB 03, 1999, WILLIAMSBURG, VIRGINIA Abbreviated Journal J Phys Chem Solids
Volume 61 Issue 2 Pages 271-274
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Despite the general belief that hydrogen-bonded ferro- and antiferroelectrics undergo a pure order/disorder transition at the structural instability, new NMR data and a new theoretical concept yield convincing evidence that a pronounced displacive component is present in these systems, which modifies substantially the temperature dependencies of the tunnel and lattice mode frequencies. The experiments and their interpretation are presented. (C) 1999 Elsevier Science Ltd. All rights reserved.
Address
Corporate Author Thesis
Publisher Pergamon-elsevier science ltd Place of Publication Oxford Editor
Language Wos 000084147000020 Publication Date 2002-07-25
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 2.059 Times cited 8 Open Access
Notes Approved Most recent IF: 2.059; 2000 IF: 1.003
Call Number (down) UA @ lucian @ c:irua:103469 Serial 2660
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Author Hervieu, M.; Martin, C.; Maignan, A.; Van Tendeloo, G.; Jirak, Z.; Hejtmanek, J.; Barnabe, A.; Thopart, D.; Raveau, B.
Title Structural and magnetotransport transitions in the electron-doped Pr1-xSrxMnO3(0.85\leq x\leq1) manganites Type A1 Journal article
Year 2000 Publication Chemistry and materials Abbreviated Journal Chem Mater
Volume 12 Issue 5 Pages 1456-1462
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The exploration of the Mn4+-rich side of the Pr1-xSrxMnO3 system has allowed the extension of the domain of the cubic perovskite, by using a two-step process, combining synthesis under Ar flow at high temperature and O-2 pressure annealing at lower temperature. We show that these Pr-doped cubic perovskites exhibit a coupled structural (cubic-tetragonal) and magnetic (para-antiferro) transition connected with a resistivity jump at the same temperature. The strong interplay between lattice, charges, and spins for these oxides results from the appearance at low temperature of the distorted C-type antiferromagnetic structure. The Pr1-xSrxMnO3 magnetic phase diagram shows, for 0.9 less than or equal to x less than or equal to 1 (i.e., on the Mn4+-rich side), the existence at low temperature of C- and G-type antiferromagnetism. The absence of ferromagnetic-antiferromagnetic competition explains that magnetoresistante properties are not observed in this system, in contrast to Mn4+-rich Ln(1-x)Ca(x)MnO(3) systems.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000087136800039 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 24 Open Access
Notes Approved Most recent IF: 9.466; 2000 IF: 3.580
Call Number (down) UA @ lucian @ c:irua:103454 Serial 3198
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Author Van Tendeloo, G.; Garlea, O.; Darie, C.; Bougerol-Chaillout, C.; Bordet, P.
Title The fine structure of YCuO2+x delafossite determined by synchrotron powder diffraction and electron microscopy Type A1 Journal article
Year 2001 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 156 Issue 2 Pages 428-436
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract YCuO2 delafossite crystallizes into two stacking variants; hexagonal 2H or rhombohedral 3R, depending on the preparation conditions. The structure of the fully oxygenated material YCuO2.50 has been determined as orthorhombic (a(O) = 6.1961 Angstrom; b(O) = 11.2158 Angstrom; c(O) = 7.1505 Angstrom; space group Pnma). The structure is based on the hexagonal 2H structure (a(O) = a(H)root3; b(O) = c(H); c(O) = 2a(H)). Upon incomplete oxidation, a different YCuOZ phase with ideal composition YCuO2.33 and lattice parameters a(H root)3, a(H)root3, c(H) is also formed. Diffraction patterns are often very complex because of the presence of planar defects and intergrowth of both phases. Under electron beam irradiation, oxygen is released from the structure and one phase gradually transforms into the other. (C) 2001 Academic Press.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000167252000025 Publication Date 2002-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 33 Open Access
Notes Approved Most recent IF: 2.299; 2001 IF: 1.614
Call Number (down) UA @ lucian @ c:irua:103425 Serial 3581
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Author Stuer, C.; van Landuyt, J.; Bender, H.; de Wolf, I.; Rooyackers, R.; Badenes, G.
Title Investigation by convergent beam electron diffraction of the stress around shallow trench isolation structures Type A1 Journal article
Year 2001 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 148 Issue 11 Pages G597-G601
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Convergent beam electron diffraction (CBED) is used in this study to investigate the stress distribution around shallow trench isolation (STI) structures. Attention is given to the influence of the different processing parameters and the width and spacing of the structures. The use of a wet or a dry pregate oxidation is found to have a strong influence on the stress behavior. Isolated lines show more stress, leading to the formation of defects in the silicon substrate if a wet pregate oxidation is used. The CBED analyses are compared with micro-Raman and bright-field transmission electron microscopy measurements. (C) 2001 The Electrochemical Society.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000171653100038 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited 13 Open Access
Notes Approved Most recent IF: 3.259; 2001 IF: 2.033
Call Number (down) UA @ lucian @ c:irua:103394 Serial 1725
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Author Verberck, B.; Michel, K.H.; Nikolaev, A.V.
Title Crystal structures of polymerized fullerides AC60, A=K, Rb, Cs, and alkali-mediated interactions Type A1 Journal article
Year 2002 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 116 Issue 23 Pages 10462-10474
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Starting from a model of rigid interacting C-60 polymer chains on an orthorhombic lattice, we study the mutual orientation of the chains and the stability of the crystalline structures Pmnn and I2/m. We take into account (i) van der Waals interactions and electric quadrupole interactions between C-60 monomers on different chains as well as (ii) interactions of the monomers with the surrounding alkali atoms. The direct interactions (i) always lead to an antiferrorotational structure Pmnn with alternate orientation of the C-60 chains in planes (001). The interactions (ii) with the alkalis consist of two parts: translation-rotation (TR) coupling where the orientations of the chains interact with displacements of the alkalis, and quadrupolar electronic polarizability (ep) coupling, where the electric quadrupoles on the C-60 monomers interact with induced quadrupoles due to excited electronic d-states of the alkalis. Both interactions (ii) lead to an effective orientation-orientation interaction between the C-60 chains and always favor the ferrorotational structure I2/m, where C-60 chains have a same orientation. The structures Pmnn for KC60 and I2/m for Rb- and CsC60 are the result of a competition between the direct interaction (i) and the alkali-mediated interactions (ii). In Rb- and CsC60 the latter are found to be dominant, the preponderant role being played by the quadrupolar electronic polarizability of the alkali ions. (C) 2002 American Institute of Physics.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000175905800044 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 12 Open Access
Notes Approved Most recent IF: 2.965; 2002 IF: 2.998
Call Number (down) UA @ lucian @ c:irua:103350 Serial 578
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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 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 (down) UA @ lucian @ c:irua:103300 Serial 24
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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 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 (down) UA @ lucian @ c:irua:103284 Serial 1179
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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 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 (down) UA @ lucian @ c:irua:103265 Serial 2618
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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 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 (down) UA @ lucian @ c:irua:103253 Serial 2457
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Author Recham, N.; Casas-Cabanas, M.; Cabana, J.; Grey, C.P.; Jumas, J.-C.; Dupont, L.; Armand, M.; Tarascon, J.-M.
Title Formation of a complete solid solution between the triphylite and fayalite olivine structures Type A1 Journal article
Year 2008 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 20 Issue 21 Pages 6798-6809
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The recent infatuation for LiFePO4 as positive electrode material in Li-ion batteries has prompted a renewed interest in olivine-type structures, with a view to enhance their conduction proper-ties. We show that the dual substitution of Li for Fe and of P for Si in the olivine LiFePO4 phase leads to a complete solid solution Li1-xFe1+xP1-xSixO4 as deduced from combined X-ray diffraction, Mossbauer, and NMR experiments. Our findings challenge the common belief that the anionic network cannot be substituted. Moreover. it is found that such a substitution promotes Li intersite mixing between the olivine M1 and M2 sites. Such mixing, together with the worsening of the conducting properties of the dually substituted samples, is believed to be responsible for the poor electrochemical performances of the member's series. Beyond x = 0.20, the samples were electrochemically inactive. While the current materials are disappointing application-wise, such a study provides clues to the rich chemistry remaining to be unveiled with olivine-type structures in particular and polyanionic compounds in general.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000260658100036 Publication Date 2008-10-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 35 Open Access
Notes Approved Most recent IF: 9.466; 2008 IF: 5.046
Call Number (down) UA @ lucian @ c:irua:103082 Serial 1255
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