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Author (up) Schütte, K.; Doddi, A.; Kroll, C.; Meyer, H.; Wiktor, C.; Gemel, C.; Van Tendeloo, G.; Fischer, R.A.; Janiak, C.
Title Colloidal nickel/gallium nanoalloys obtained from organometallic precursors in conventional organic solvents and in ionic liquids : noble-metal-free alkyne semihydrogenation catalysts Type A1 Journal article
Year 2014 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 6 Issue 10 Pages 5532-5544
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Efforts to replace noble-metal catalysts by low-cost alternatives are of constant interest. The organometallic, non-aqueous wet-chemical synthesis of various hitherto unknown nanocrystalline Ni/Ga intermetallic materials and the use of NiGa for the selective semihydrogenation of alkynes to alkenes are reported. Thermal co-hydrogenolysis of the all-hydrocarbon precursors [Ni(COD)(2)] (COD = 1,5-cyclooctadiene) and GaCp* (Cp* = pentamethylcyclopentadienyl) in high-boiling organic solvents mesitylene and n-decane in molar ratios of 1 : 1, 2 : 3 and 3 : 1 yields the nano-crystalline powder materials of the over-all compositions NiGa, Ni2Ga3 and Ni3Ga, respectively. Microwave induced co-pyrolysis of the same precursors without additional hydrogen in the ionic liquid [BMIm][BF4] (BMIm = 1-butyl-3-methyl-imidazolium) selectively yields the intermetallic phases NiGa and Ni3Ga from the respective 1 : 1 and 3 : 1 molar ratios of the precursors. The obtained materials are characterized by transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), IR, powder X-ray diffraction (PXRD) and atomic absorption spectroscopy (AAS). The single-source precursor [Ni(GaCp*)(PMe3)(3)] with a fixed Ni : Ga stoichiometry of 1 : 1 was employed as well. In comparison with the co-hydrogenolytic dual precursor source approach it turned out to be less practical due to inefficient nickel incorporation caused by the parasitic formation of stable [Ni(PMe3)(4)]. The use of ionic liquid [BMIm][BF4] as a non-conventional solvent to control the reaction and stabilize the nanoparticles proved to be particularly advantageous and stable colloids of the nanoalloys NiGa and Ni3Ga were obtained. A phase-selective Ni/Ga colloid synthesis in conventional solvents and in the presence of surfactants such as hexadecylamine (HDA) was not feasible due to the undesired reactivity of HDA with GaCp* leading to inefficient gallium incorporation. Recyclable NiGa nanoparticles selectively semihydrogenate 1-octyne and diphenylacetylene (tolan) to 1-octene and diphenylethylene, respectively, with a yield of about 90% and selectivities of up to 94 and 87%. Ni-NPs yield alkanes with a selectivity of 97 or 78%, respectively, under the same conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000335148800069 Publication Date 2014-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 40 Open Access
Notes Approved Most recent IF: 7.367; 2014 IF: 7.394
Call Number UA @ lucian @ c:irua:117251 Serial 390
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Author (up) Schutyser, W.; Van den Bosch, S.; Dijkmans, J.; Turner, S.; Meledina, M.; Van Tendeloo, G.; Debecker, D.P.; Sels, B.F.
Title Selective nickel-catalyzed conversion of model and lignin-derived phenolic compounds to cyclohexanone-based polymer building blocks Type A1 Journal article
Year 2015 Publication Chemsuschem Abbreviated Journal Chemsuschem
Volume 8 Issue 8 Pages 1805-1818
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Valorization of lignin is essential for the economics of future lignocellulosic biorefineries. Lignin is converted into novel polymer building blocks through four steps: catalytic hydroprocessing of softwood to form 4-alkylguaiacols, their conversion into 4-alkylcyclohexanols, followed by dehydrogenation to form cyclohexanones, and Baeyer-Villiger oxidation to give caprolactones. The formation of alkylated cyclohexanols is one of the most difficult steps in the series. A liquid-phase process in the presence of nickel on CeO2 or ZrO2 catalysts is demonstrated herein to give the highest cyclohexanol yields. The catalytic reaction with 4-alkylguaiacols follows two parallel pathways with comparable rates: 1) ring hydrogenation with the formation of the corresponding alkylated 2-methoxycyclohexanol, and 2) demethoxylation to form 4-alkylphenol. Although subsequent phenol to cyclohexanol conversion is fast, the rate is limited for the removal of the methoxy group from 2-methoxycyclohexanol. Overall, this last reaction is the rate-limiting step and requires a sufficient temperature (> 250 degrees C) to overcome the energy barrier. Substrate reactivity (with respect to the type of alkyl chain) and details of the catalyst properties (nickel loading and nickel particle size) on the reaction rates are reported in detail for the Ni/CeO2 catalyst. The best Ni/CeO2 catalyst reaches 4-alkylcyclohexanol yields over 80 %, is even able to convert real softwood-derived guaiacol mixtures and can be reused in subsequent experiments. A proof of principle of the projected cascade conversion of lignocellulose feedstock entirely into caprolactone is demonstrated by using Cu/ZrO2 for the dehydrogenation step to produce the resultant cyclohexanones (approximate to 80%) and tin-containing beta zeolite to form 4-alkyl-e-caprolactones in high yields, according to a Baeyer-Villiger-type oxidation with H2O2.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000355220300020 Publication Date 2015-04-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1864-5631; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.226 Times cited 71 Open Access
Notes Fwo Approved Most recent IF: 7.226; 2015 IF: 7.657
Call Number c:irua:126406 Serial 2967
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Author (up) Schweigert, I.V.; Alexandrov, A.L.; Ariskin, D.A.; Peeters, F.M.; Stefanović, I.; Kovačević, E.; Berndt, J.; Winter, J.
Title Effect of transport of growing nanoparticles on capacitively coupled rf discharge dynamics Type A1 Journal article
Year 2008 Publication Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics Abbreviated Journal Phys Rev E
Volume 78 Issue 2 Pages 026410,1-026410,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present experimental and numerical studies of the properties of a capacitively coupled 13.56 MHz discharge in a mixture of Ar and C2H2 with growing nanosize particles. It is found that at the initial stage of the growth, nanoparticles are accumulated near the sheath-plasma boundaries, where the ionization by electrons is maximal. The nanoparticles suppress the ionization due to the absorbing fast electrons and stimulate a quick change of the plasma parameters followed by a transition between different modes of discharge operation. At that moment the peaked distribution of the dust particles transforms into a flat one.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000259263700071 Publication Date 2008-08-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 36 Open Access
Notes Approved Most recent IF: 2.366; 2008 IF: 2.508
Call Number UA @ lucian @ c:irua:76552 Serial 851
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Author (up) Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M.
Title Enhanced stability of the square lattice of a classical bilayer Wigner crystal Type A1 Journal article
Year 1999 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 60 Issue Pages 14665-14674
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000084141700045 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 31 Open Access
Notes Approved Most recent IF: 3.836; 1999 IF: NA
Call Number UA @ lucian @ c:irua:27004 Serial 1057
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Author (up) Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M.
Title Influence of the lattice symmetry on melting of the bilayer Wigner crystal Type A1 Journal article
Year 2000 Publication Journal de physique: 4 T2 – International Conference on Strongly Coupled Coulomb Systems, SEP 04-10, 1999, ST MALO, FRANCE Abbreviated Journal J Phys Iv
Volume 10 Issue P5 Pages 117-120
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The melting transition of the five different lattices of a bilayer crystal is studied using the Monte-Carlo (MC) technique. We found the surprising result that the square lattice has a substantial larger melting temperature as compared to the other lattice structures, which is a consequence of the specific topology of the temperature induced defects. A new melting criterion is formulated which we show to be universal for bilayers as well as for single layer crystals.
Address
Corporate Author Thesis
Publisher Place of Publication Les Ulis Editor
Language Wos 000087026300016 Publication Date 2007-07-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1155-4339; ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103954 Serial 1647
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Author (up) Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M.
Title Melting of the classical bilayer Wigner crystal: influence of the lattice symmetry Type A1 Journal article
Year 1999 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 82 Issue Pages 5293-5296
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract http://anet.uantwerpen.be/docman/irua/f3d874/7910.pdf
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000081152700029 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 64 Open Access
Notes Approved Most recent IF: 8.462; 1999 IF: 6.095
Call Number UA @ lucian @ c:irua:24151 Serial 1988
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Author (up) Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M.
Title Perturbation of collisional plasma flow around a charged dust particle: kinetic analysis Type A1 Journal article
Year 2005 Publication Physics of plasmas Abbreviated Journal Phys Plasmas
Volume 12 Issue 11 Pages 113501,1-9
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Woodbury, N.Y. Editor
Language Wos 000233569600046 Publication Date 2005-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1070-664X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.115 Times cited 15 Open Access
Notes Approved Most recent IF: 2.115; 2005 IF: 2.182
Call Number UA @ lucian @ c:irua:56048 Serial 2575
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Author (up) Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M.
Title Properties of two-dimensional Coulomb clusters confined in a ring Type A1 Journal article
Year 1996 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 54 Issue Pages 10827-10834
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1996VT67400087 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 27 Open Access
Notes Approved CHEMISTRY, PHYSICAL 77/144 Q3 # MATHEMATICS, INTERDISCIPLINARY 19/101 Q1 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 17/35 Q2 #
Call Number UA @ lucian @ c:irua:15791 Serial 2730
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Author (up) Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M.
Title Radial fluctuations induced stabilization of the ordered state in two-dimensional classical clusters Type A1 Journal article
Year 2000 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 84 Issue Pages 4381-4384
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000086941600032 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 69 Open Access
Notes Approved Most recent IF: 8.462; 2000 IF: 6.462
Call Number UA @ lucian @ c:irua:28518 Serial 2807
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Author (up) Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M.
Title Reply to Rinn and Maass Type A1 Journal article
Year 2001 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 86 Issue 20 Pages 4712
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000168623500075 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 5 Open Access
Notes Approved Most recent IF: 8.462; 2001 IF: 6.668
Call Number UA @ lucian @ c:irua:37308 Serial 2877
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Dynamics of a finite classical two-dimensional system Type A1 Journal article
Year 1994 Publication Superlattices and microstructures Abbreviated Journal Superlattice Microst
Volume 16 Issue 3 Pages 243-247
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The spectral properties of a classical two-dimensional (2D) cluster of charged particles which are confined by a quadratic potential are calculated. Using the method of Newton optimization we obtain the ground state and the metastable states. For a given configuration the eigenvectors and eigenfrequencies for the normal modes are obtained using the Householder diagonalization technique for the dynamical matrix whose elements are the second derivative of the potential energy. For small clusters the lowest excitation corresponds to an intershell rotation. Magic numbers are associated to clusters which are most stable against intershell rotation. For large clusters the lowest excitation is a vortex/anti-vortex pair.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos A1994QE75400007 Publication Date 2009-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0749-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.097 Times cited 4 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:99951 Serial 772
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Filed-cooled vortex states in mesoscopic superconducting samples Type A1 Journal article
Year 2000 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 180 Issue Pages 426-431
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000087245200080 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 17 Open Access
Notes Approved Most recent IF: 1.404; 2000 IF: 1.489
Call Number UA @ lucian @ c:irua:28523 Serial 1193
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Flux penetration and expulsion in thin superconducting disks Type A1 Journal article
Year 1999 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 83 Issue Pages 2409-2412
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000082661100033 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 104 Open Access
Notes Approved Most recent IF: 8.462; 1999 IF: 6.095
Call Number UA @ lucian @ c:irua:26998 Serial 1241
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Influence of the confinement geometry on surface superconductivity Type A1 Journal article
Year 1999 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 60 Issue Pages 3084-3087
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000081986300033 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 88 Open Access
Notes Approved Most recent IF: 3.836; 1999 IF: NA
Call Number UA @ lucian @ c:irua:27015 Serial 1646
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Phase transitions in thin mesoscopic superconducting disks Type A1 Journal article
Year 1998 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 57 Issue Pages 13817-13832
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000074061700068 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 200 Open Access
Notes Approved Most recent IF: 3.836; 1998 IF: NA
Call Number UA @ lucian @ c:irua:24167 Serial 2598
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Spectral properties of classical two-dimensional clusters Type A1 Journal article
Year 1995 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 51 Issue Pages 7700-7713
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1995QQ59800034 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 237 Open Access
Notes Approved CHEMISTRY, PHYSICAL 77/144 Q3 # MATHEMATICS, INTERDISCIPLINARY 19/101 Q1 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 17/35 Q2 #
Call Number UA @ lucian @ c:irua:12198 Serial 3072
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Time dependent properties of classical artificial atoms Type A1 Journal article
Year 1998 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 10 Issue Pages 2417-2435
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000072951000006 Publication Date 2002-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 18 Open Access
Notes Approved Most recent IF: 2.649; 1998 IF: 1.645
Call Number UA @ lucian @ c:irua:24175 Serial 3665
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Author (up) Schweigert, V.A.; Peeters, F.M.
Title Transitions between different superconducting states in mesoscopic disks Type A1 Journal article
Year 2000 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 144 Issue Pages 266-271
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000087245200047 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 24 Open Access
Notes Approved Most recent IF: 1.404; 2000 IF: 1.489
Call Number UA @ lucian @ c:irua:28521 Serial 3701
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Author (up) Schweigert, V.A.; Peeters, F.M.; Deo, P.S.
Title Vortex phase diagram for mesoscopic superconducting disks Type A1 Journal article
Year 1998 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 81 Issue Pages 2783-2786
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000076133300041 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.462 Times cited 327 Open Access
Notes Approved Most recent IF: 8.462; 1998 IF: 6.017
Call Number UA @ lucian @ c:irua:24154 Serial 3879
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Author (up) Scipioni, R.; Matsubara, M.; Ruiz, E.; Massobrio, C.; Boero, M.
Title Thermal behavior of Si-doped fullerenes vs their structural stability at T = 0 K : a density functional study Type A1 Journal article
Year 2011 Publication Chemical physics letters Abbreviated Journal Chem Phys Lett
Volume 510 Issue 1/3 Pages 14-17
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We establish the topological conditions underlying the thermal stability of C30Si30 clusters. Two topologies have been considered: a segregated one, where Si and C atoms lie on neighboring and yet, separated parts of the cage, and a non-segregated one, where the number of SiC bonds is maximized. The segregated network is energetically favored against the non-segregated one, both structures being fully relaxed at T = 0 K. Conversely, the non-segregated structure is the only one stable at finite temperatures, regardless of the nature of the local states (d or p) included in the KleynmanBylander construction.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000291478400002 Publication Date 2011-05-20
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 14 Open Access
Notes Approved Most recent IF: 1.815; 2011 IF: 2.337
Call Number UA @ lucian @ c:irua:90453 Serial 3625
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Author (up) Sciutto, G.; Legrand, S.; Catelli, E.; Prati, S.; Malegori, C.; Oliveri, P.; Janssens, K.; Mazzeo, R.
Title Macroscopic mid-FTIR mapping and clustering-based automated data-reduction : an advanced diagnostic tool for in situ investigations of artworks Type A1 Journal article
Year 2020 Publication Talanta Abbreviated Journal Talanta
Volume 209 Issue Pages 120575-120577
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The present study describes a multivariate strategy that can be used for automatic on-site processing of reflection mode macro FTIR mapping (MA-rFTIR) data obtained during investigation of artworks. The chemometric strategy is based on the integration of principal component analysis (PCA) with a clustering approach in the space subtended by the three lowest-order principal components and allows to automatically identify the regions of interest (ROIs) of the area scanned and to extract the average FTIR spectra related to each ROI. Thanks to the automatic data management, in-field HSI (hyperspectral imaging)-based analyses may be performed even by staff lacking specific advanced chemometric expertise, as it is sometimes the case for conservation scientists or conservators with a scientific background. MA-rFTIR was only recently introduced in the conservation field and, in this work the technique was employed to characterize the surface of metallic artefacts. The analytical protocol was employed as part of a rapid procedure to evaluate the conservation state and the performance of cleaning methods on bronze objects. Both activities are commonly part of restoration campaigns of bronzes and require an on-site analytical procedure for efficient and effective diagnosis. The performance of the method was first evaluated on aged standard samples (bronzes with a layer of green basic copper hydroxysulphate, treated with different organic coatings) and then scrutinized in situ on areas of the 16th century Neptune fountain statue (Piazza del Nettuno, Bologna, Italy) by Gianbologna.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000509632900088 Publication Date 2019-11-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-9140; 1873-3573 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.1 Times cited Open Access
Notes ; ; Approved Most recent IF: 6.1; 2020 IF: 4.162
Call Number UA @ admin @ c:irua:166476 Serial 6557
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Author (up) Scolfaro, D.; Finamor, M.; Trinchao, L.O.; Rosa, B.L.T.; Chaves, A.; Santos, P., V.; Iikawa, F.; Couto, O.D.D., Jr.
Title Acoustically driven stark effect in transition metal dichalcogenide monolayers Type A1 Journal article
Year 2021 Publication Acs Nano Abbreviated Journal Acs Nano
Volume 15 Issue 9 Pages 15371-15380
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The Stark effect is one of the most efficient mechanisms to manipulate many-body states in nanostructured systems. In mono- and few-layer transition metal dichalcogenides, it has been successfully induced by optical and electric field means. Here, we tune the optical emission energies and dissociate excitonic states in MoSe2 monolayers employing the 220 MHz in-plane piezoelectric field carried by surface acoustic waves. We transfer the monolayers to high dielectric constant piezoelectric substrates, where the neutral exciton binding energy is reduced, allowing us to efficiently quench (above 90%) and red-shift the excitonic optical emissions. A model for the acoustically induced Stark effect yields neutral exciton and trion in-plane polarizabilities of 530 and 630 x 10(-5) meV/(kV/cm)(2), respectively, which are considerably larger than those reported for monolayers encapsulated in hexagonal boron nitride. Large in-plane polarizabilities are an attractive ingredient to manipulate and modulate multiexciton interactions in two-dimensional semiconductor nanostructures for optoelectronic applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000703553600129 Publication Date 2021-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 13.942
Call Number UA @ admin @ c:irua:182545 Serial 7415
Permanent link to this record
 

 
Author (up) Scot, V.; Fernandez, J.E.; Vincze, L.; Janssens, K.
Title 3D extension of the Monte Carlo code MCSHAPE for photon-matter interactions in the heterogeneous media Type A1 Journal article
Year 2007 Publication Nuclear instruments & methods in physics research section B-Beam interactions with materiala and atoms Abbreviated Journal
Volume 263 Issue 1 Pages 204-208
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000250798000042 Publication Date 2007-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 15 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:66755 Serial 5448
Permanent link to this record
 

 
Author (up) Scotti di Uccio, U.; Miletto Granozio, F.; di Chiara, A.; Tafuri, F.; Lebedev, O.I.; Verbist, K.; Van Tendeloo, G.
Title Phase competition between Y2BaCuO5 and Y2O3 precipitates in Y-rich YBCO thin films Type A1 Journal article
Year 1999 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 321 Issue Pages 162-176
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000083004400004 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 17 Open Access
Notes Approved Most recent IF: 1.404; 1999 IF: 1.114
Call Number UA @ lucian @ c:irua:29725 Serial 2579
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Author (up) Scuracchio, P.; Costamagna; Peeters, F.M.; Dobry, A.
Title Role of atomic vacancies and boundary conditions on ballistic thermal transport in graphene nanoribbons Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 90 Issue 3 Pages 035429
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Quantum thermal transport in armchair and zigzag graphene nanoribbons is investigated in the presence of single atomic vacancies and subject to different boundary conditions. We start with a full comparison of the phonon polarizations and energy dispersions as given by a fifth-nearest-neighbor force-constant model (5NNFCM) and by elasticity theory of continuum membranes (ETCM). For free-edge ribbons, we discuss the behavior of an additional acoustic edge-localized flexural mode, known as fourth acoustic branch (4ZA), which has a small gap when it is obtained by the 5NNFCM. Then, we show that ribbons with supported edges have a sample-size dependent energy gap in the phonon spectrum which is particularly large for in-plane modes. Irrespective to the calculation method and the boundary condition, the dependence of the energy gap for the low-energy optical phonon modes against the ribbon width W is found to be proportional to 1/W for in-plane, and 1/W-2 for out-of-plane phonon modes. Using the 5NNFCM, the ballistic thermal conductance and its contributions from every single phonon mode are then obtained by the nonequilibrium Green's function technique. We found that, while edge and central localized single atomic vacancies do not affect the low-energy transmission function of in-plane phonon modes, they reduce considerably the contributions of the flexural modes. On the other hand, in-plane modes contributions are strongly dependent on the boundary conditions and at low temperatures can be highly reduced in supported-edge samples. These findings could open a route to engineer graphene based devices where it is possible to discriminate the relative contribution of polarized phonons and to tune the thermal transport on the nanoscale.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000339443800009 Publication Date 2014-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 20 Open Access
Notes ; Discussions with S. D. Dalosto and K. H. Michel are gratefully acknowledged. This work was partially supported by PIP 11220090100392 of CONICET (Argentina) and the Flemish Science Foundation (FWO-VI). We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:118698 Serial 2911
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Author (up) Scuracchio, P.; Dobry, A.; Costamagna, S.; Peeters, F.M.
Title Tuning the polarized quantum phonon transmission in graphene nanoribbons Type A1 Journal article
Year 2015 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 26 Issue 26 Pages 305401
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We propose systems that allow a tuning of the phonon transmission function T(omega) in graphene nanoribbons by using C-13 isotope barriers, antidot structures, and distinct boundary conditions. Phonon modes are obtained by an interatomic fifth-nearest neighbor force-constant model (5NNFCM) and T(omega) is calculated using the non-equilibrium Green's function formalism. We show that by imposing partial fixed boundary conditions it is possible to restrict contributions of the in-plane phonon modes to T(omega) at low energy. On the contrary, the transmission functions of out-of-plane phonon modes can be diminished by proper antidot or isotope arrangements. In particular, we show that a periodic array of them leads to sharp dips in the transmission function at certain frequencies omega(nu) which can be pre-defined as desired by controlling their relative distance and size. With this, we demonstrated that by adequate engineering it is possible to govern the magnitude of the ballistic transmission functions T(omega) in graphene nanoribbons. We discuss the implications of these results in the design of controlled thermal transport at the nanoscale as well as in the enhancement of thermo-electric features of graphene-based materials.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000358675900010 Publication Date 2015-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484;1361-6528; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 5 Open Access
Notes ; Discussions with C E Repetto, C R Stia and K H Michel are gratefully acknowledged. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and PIP 11220090100392 of CONICET (Argentina). We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. ; Approved Most recent IF: 3.44; 2015 IF: 3.821
Call Number c:irua:127186 Serial 3759
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Author (up) Scuracchio, P.; Michel, K.H.; Peeters, F.M.
Title Phonon hydrodynamics, thermal conductivity, and second sound in two-dimensional crystals Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue 14 Pages 144303
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Starting from our previous work in which we obtained a system of coupled integrodifferential equations for acoustic sound waves and phonon density fluctuations in two-dimensional (2D) crystals, we derive here the corresponding hydrodynamic equations, and we study their consequences as a function of temperature and frequency. These phenomena encompass propagation and damping of acoustic sound waves, diffusive heat conduction, second sound, and Poiseuille heat flow, all of which are characterized by specific transport coefficients. We calculate these coefficients by means of correlation functions without using the concept of relaxation time. Numerical calculations are performed as well in order to show the temperature dependence of the transport coefficients and of the thermal conductivity. As a consequence of thermal tension, mechanical and thermal phenomena are coupled. We calculate the dynamic susceptibilities for displacement and temperature fluctuations and study their resonances. Due to the thermomechanical coupling, the thermal resonances such as the Landau-Placzek peak and the second-sound doublet appear in the displacement susceptibility, and conversely the acoustic sound wave doublet appears in the temperature susceptibility, Our analytical results not only apply to graphene, but they are also valid for arbitrary 2D crystals with hexagonal symmetry, such as 2D hexagonal boron nitride, 2H-transition-metal dichalcogenides, and oxides.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000464717300006 Publication Date 2019-04-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 13 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:159346 Serial 5225
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Author (up) Sebhatu, K.T.; Gezahegn, T.W.; Berhanu, T.; Maertens, M.; Van Passel, S.; D'Haese, M.
Title Exploring variability across cooperatives : economic performance of agricultural cooperatives in northern Ethiopia Type A1 Journal article
Year 2021 Publication The international food and agribusiness management review Abbreviated Journal
Volume 24 Issue 3 Pages 397-419
Keywords A1 Journal article; Engineering Management (ENM)
Abstract The number of agricultural cooperatives increased quickly in Ethiopia since the 1990s. While many papers studied the impact of membership of Ethiopian cooperatives, not much is known on their performance. This study takes a cooperative-level perspective which is unique in an African context. It compares the economic performance proxied by sales revenue and profit of a wide range of agricultural cooperatives in northern Ethiopia. Data were collected from 511 agricultural cooperatives in 12 districts of Tigray. The contributing factors of the performance are analyzed with Ordinary Least Squares regression (OLS) and Heckman selection models. Our results underscore the importance of membership size, total assets, presence of conflict among members, and union membership. Chairperson characteristics and the internal organization of a cooperative seem to be less correlated to performance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000645416400002 Publication Date 2021-03-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1096-7508; 1559-2448 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:179025 Serial 6923
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Author (up) Sebhatu, K.T.; Gezahegn, T.W.; Berhanu, T.; Maertens, M.; Van Passel, S.; D’Haese, M.
Title Conflict, fraud, and distrust in Ethiopian agricultural cooperatives Type A1 Journal Article
Year 2020 Publication Journal of Co-operative Organization and Management Abbreviated Journal Journal of Co-operative Organization and Management
Volume 8 Issue 1 Pages 100106
Keywords A1 Journal Article; Agricultural cooperatives; Cooperative size; Conflict; Fraud; Distrust; Ethiopia; Engineering Management (ENM) ;
Abstract Agricultural cooperatives are seen as an efficient way for smallholder farmers to create bargaining power in order to achieve poverty reduction and food security. However, the success of these cooperatives depends on their ability to maintain their social capital, which is at the core of collective action. A few studies have addressed issues of member participation, commitment, and trust, yet less is known about rural cooperatives in developing countries as a social organization. It is also unclear whether a relationship exists between cooperative size and the incidence of conflict, fraud, and distrust. Using unique data collected from 511 agricultural cooperatives in 12 districts of Tigray region in northern Ethiopia, this paper examines the effects of cooperative size on conflict, fraud, and distrust. We used instrumental variables (IV) probit estimation techniques, accounting for endogeneity of membership size, to confirm that cooperative size does affect the occurrence of conflict, fraud, and trust. The results also indicate that other influencing factors include: cooperative age, number of employees, payment of dividends based on transaction volume, and heterogeneity of member goals.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000536594400001 Publication Date 2020-04-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2213297X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes The authors would like to thank the office of the twelve districts, facilitators and Cooperative Promotion Agency staff for their collaboration in facilitating the field survey, most of all the chair- and vice-chairpersons of the study Agricultural Cooperatives who had to respond to all our questions with seriousness and patience. Approved Most recent IF: NA
Call Number ENM @ enm @c:irua:170073 Serial 6379
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Author (up) Sebhatu, K.T.; Taheri, F.; Berhanu, T.; Maertens, M.; Van Passel, S.; D'Haese, M.
Title Beyond focus : exploring variability of service provision of agricultural cooperatives Type A1 Journal article
Year 2021 Publication Annals of public and cooperative economics Abbreviated Journal
Volume 92 Issue 2 Pages 207-231
Keywords A1 Journal article; Economics; Engineering Management (ENM)
Abstract The wide array of services provided by agricultural cooperatives for their members is often not considered in academic studies. Addressing this gap in the literature, our paper explores the wide array of services provided by agricultural cooperatives and how these extend beyond those they were initially intended to provide. We study the extent and characteristics of service portfolios from 511 agricultural cooperatives in the Tigray region of Ethiopia. Results from two-limit Tobit models confirm that government and NGO-initiated cooperatives have a wide service portfolio compared to member-initiated cooperatives. In many of the studied cooperatives, the services they provide and their portfolios are more diverse than expected. Cooperatives seem to go beyond their focal areas of intervention. Also, those cooperatives that are more outward-oriented and where the chair has contact with other cooperatives or businesses, have a wider service portfolio. These results may help to explain the mixed findings on the impact of cooperative membership.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000583855500001 Publication Date 2020-10-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1370-4788; 1467-8292 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:173574 Serial 6916
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