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Author Neyts, E.C.; Ostrikov, K.K.; Sunkara, M.K.; Bogaerts, A.
Title Plasma Catalysis: Synergistic Effects at the Nanoscale Type A1 Journal article
Year 2015 Publication Chemical reviews Abbreviated Journal Chem Rev
Volume 115 Issue 115 Pages 13408-13446
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Thermal-catalytic gas processing is integral to many current industrial processes. Ever-increasing demands on conversion and energy efficiencies are a strong driving force for the development of alternative approaches. Similarly, synthesis of several functional materials (such as nanowires and nanotubes) demands special processing conditions. Plasma catalysis provides such an alternative, where the catalytic process is complemented by the use of plasmas that activate the source gas. This combination is often observed to result in a synergy between plasma and catalyst. This Review introduces the current state-of-the-art in plasma catalysis, including numerous examples where plasma catalysis has demonstrated its benefits or shows future potential, including CO2 conversion, hydrocarbon reforming, synthesis of nanomaterials, ammonia production, and abatement of toxic waste gases. The underlying mechanisms governing these applications, as resulting from the interaction between the plasma and the catalyst, render the process highly complex, and little is known about the factors leading to the often-observed synergy. This Review critically examines the catalytic mechanisms relevant to each specific application.
Address Department of Chemistry, Research Group PLASMANT, Universiteit Antwerpen , Universiteitsplein 1, 2610 Wilrijk-Antwerp, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos (up) 000367563000006 Publication Date 2015-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0009-2665 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 47.928 Times cited 204 Open Access
Notes ECN and AB gratefully acknowledge financial support from the Fund of Scientific Research Flanders (FWO), Belgium, Grant Number G.0217.14N. KO acknowledges partial support by the Australian Research Council and CSIRO’s OCE Science Leaders Program. MKS acknowledges partial support from US National Science Foundation through grants DMS 1125909 and EPSCoR 1355448 and also PhD students Babajide Ajayi, Apolo Nambo and Maria Carreon for their help. Approved Most recent IF: 47.928; 2015 IF: 46.568
Call Number c:irua:130001 Serial 3993
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Author Buh, J.; Kabanov, V.; Baranov, V.; Mrzel, A.; Kovic, A.; Mihailovic, D.
Title Control of switching between metastable superconducting states in delta-MoN nanowires Type A1 Journal article
Year 2015 Publication Nature communications Abbreviated Journal Nat Commun
Volume 6 Issue 6 Pages 10250
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The superconducting state in one-dimensional nanosystems is very delicate. While fluctuations of the phase of the superconducting wave function lead to the spontaneous decay of persistent supercurrents in thin superconducting wires and nanocircuits, discrete phase-slip fluctuations can also lead to more exotic phenomena, such as the appearance of metastable superconducting states in current-bearing wires. Here we show that switching between different metastable superconducting states in d-MoN nanowires can be very effectively manipulated by introducing small amplitude electrical noise. Furthermore, we show that deterministic switching between metastable superconducting states with different numbers of phase-slip centres can be achieved in both directions with small electrical current pulse perturbations of appropriate polarity. The observed current-controlled bi-stability is in remarkable agreement with theoretically predicted trajectories of the system switching between different limit cycle solutions of a model one-dimensional superconductor.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000367576600002 Publication Date 2015-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 8 Open Access
Notes ; ; Approved Most recent IF: 12.124; 2015 IF: 11.470
Call Number UA @ lucian @ c:irua:131108 Serial 4156
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Author De Henau, S.; Tilleman, L.; Vangheel, M.; Luyckx, E.; Trashin, S.; Pauwels, M.; Germani, F.; Vlaeminck, C.; Vanfleteren, J.R.; Bert, W.; Pesce, A.; Nardini, M.; Bolognesi, M.; De Wael, K.; Moens, L.; Dewilde, S.; Braeckman, B.P.
Title A redox signalling globin is essential for reproduction in Caenorhabditis elegans Type A1 Journal article
Year 2015 Publication Nature communications Abbreviated Journal Nat Commun
Volume 6 Issue Pages 8782
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Moderate levels of reactive oxygen species (ROS) are now recognized as redox signalling molecules. However, thus far, only mitochondria and NADPH oxidases have been identified as cellular sources of ROS in signalling. Here we identify a globin (GLB-12) that produces superoxide, a type of ROS, which serves as an essential signal for reproduction in C. elegans. We find that GLB-12 has an important role in the regulation of multiple aspects in germline development, including germ cell apoptosis. We further describe how GLB-12 displays specific molecular, biochemical and structural properties that allow this globin to act as a superoxide generator. In addition, both an intra- and extracellular superoxide dismutase act as key partners of GLB-12 to create a transmembrane redox signal. Our results show that a globin can function as a driving factor in redox signalling, and how this signal is regulated at the subcellular level by multiple control layers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000367577100002 Publication Date 2015-12-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 20 Open Access
Notes ; We thank Dr K. Matsumoto and Dr T. Mizuno for kindly providing the mek-1(ks54) sek-1(km4) double mutant, the antibody anti-PMK-1 and technical advice on antibody use; Dr D. Kim for kindly providing the pDK177 RNAi strain; Dr M. Ubbink and Dr Q. Bashir for providing CCP; Dr K. Oegema and the OD lab for sharing technical expertise; M. Couvreur for assistance in generating transgenic lines; and Dr T. Dansen for the final support. Some strains were provided by the CGC, which is funded by the NIH Office of Research Infrastructure Programs (P40 OD010440). S.D.H. and F.G. are PhD fellows of the Fund for Scientific Research (FWO). Financial support to S.D. and L.M. was provided by the University of Antwerp (BOF UA TOP 2006), to K.D.W., S.D. and S.T. by the University of Antwerp (BOF-GOA) and to S.D., L.M., B.P.B., by FWO project G.0247.09. ; Approved Most recent IF: 12.124; 2015 IF: 11.470
Call Number UA @ admin @ c:irua:129310 Serial 5809
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Author Khalilov, U.; Bogaerts, A.; Neyts, E.C.
Title Atomic scale simulation of carbon nanotube nucleation from hydrocarbon precursors Type A1 Journal article
Year 2015 Publication Nature communications Abbreviated Journal Nat Commun
Volume 6 Issue 6 Pages 10306
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Atomic scale simulations of the nucleation and growth of carbon nanotubes is essential for understanding their growth mechanism. In spite of over twenty years of simulation efforts in this area, limited progress has so far been made on addressing the role of the hydrocarbon growth precursor. Here we report on atomic scale simulations of cap nucleation of single-walled carbon nanotubes from hydrocarbon precursors. The presented mechanism emphasizes the important role of hydrogen in the nucleation process, and is discussed in relation to previously presented mechanisms. In particular, the role of hydrogen in the appearance of unstable carbon structures during in situ experimental observations as well as the initial stage of multi-walled carbon nanotube growth is discussed. The results are in good agreement with available experimental and quantum-mechanical results, and provide a basic understanding of the incubation and nucleation stages of hydrocarbon-based CNT growth at the atomic level.
Address PLASMANT research group, Department of Chemistry, University of Antwerp, Universiteitsplein 1, 2610 Antwerpen, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos (up) 000367584500001 Publication Date 2015-12-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 37 Open Access
Notes The authors gratefully acknowledge financial support from the Fund of Scientific Research Flanders (FWO), Belgium, grant number 12M1315N. The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Centre VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. We thank Professor Adri C. T. van Duin for sharing the ReaxFF code. Approved Most recent IF: 12.124; 2015 IF: 11.470
Call Number c:irua:129975 Serial 3990
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Author Paria Sena, R.; Babaryk, A.A.; Khainakov, S.; Garcia-Granda, S.; Slobodyanik, N.S.; Van Tendeloo, G.; Abakumov, A.M.; Hadermann, J.
Title A pseudo-tetragonal tungsten bronze superstructure: a combined solution of the crystal structure of K6.4(Nb,Ta)36.3O94 with advanced transmission electron microscopy and neutron diffraction Type A1 Journal article
Year 2016 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 45 Issue 45 Pages 973-979
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crystal structure of the K6.4Nb28.2Ta8.1O94 pseudo-tetragonal tungsten bronze-type oxide was determined using a combination of X-ray powder diffraction, neutron diffraction and transmission electron microscopy techniques, including electron diffraction, high angle annular dark field scanning transmission electron microscopy (HAADF-STEM), annular bright field STEM (ABF-STEM) and energy-dispersive X-ray compositional mapping (STEM-EDX). The compound crystallizes in the space group Pbam with unit cell parameters a = 37.468(9) A, b = 12.493(3) A, c = 3.95333(15) A. The structure consists of corner sharing (Nb,Ta)O6 octahedra forming trigonal, tetragonal and pentagonal tunnels. All tetragonal tunnels are occupied by K(+) ions, while 1/3 of the pentagonal tunnels are preferentially occupied by Nb(5+)/Ta(5+) and 2/3 are occupied by K(+) in a regular pattern. A fractional substitution of K(+) in the pentagonal tunnels by Nb(5+)/Ta(5+) is suggested by the analysis of the HAADF-STEM images. In contrast to similar structures, such as K2Nb8O21, also parts of the trigonal tunnels are fractionally occupied by K(+) cations.
Address Electron Microscopy for Materials Research (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020, Antwerp, Belgium. joke.hadermann@uantwerpen.be babaryk@univ.kiev.ua
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos (up) 000367614700018 Publication Date 2015-11-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1477-9226 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited 6 Open Access
Notes We thank Dr E. Suard and Dr O. Fabello for assistance in collecting the neutron diffraction data. R.P.S. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791-COUNTATOMS. The titan microscope was partly funded by the Hercules fund from the Flemish Government. The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483-ESTEEM2. AAB acknowledges the JSPDS ICDD Grant-in-Aid program (12-02).; esteem2jra1; esteem2jra2 Approved Most recent IF: 4.029
Call Number c:irua:130408 c:irua:130408 Serial 3998
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Author Rozova, M.G.; Grigoriev, V.V.; Bobrikov, I.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Tsirlin, A.A.; Abakumov, A.M.
Title Synthesis, structure and magnetic ordering of the mullite-type Bi2Fe4-xCrxO9 solid solutions with a frustrated pentagonal Cairo lattice Type A1 Journal article
Year 2016 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 45 Issue 45 Pages 1192-1200
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Highly homogeneous mullite-type solid solutions Bi2Fe4-xCrxO9 (x = 0.5, 1, 1.2) were synthesized using a soft chemistry technique followed by a solid-state reaction in Ar. The crystal structure of Bi2Fe3CrO9 was investigated using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy (S.G. Pbam, a = 7.95579(9) angstrom , b = 8.39145(9) angstrom, c = 5.98242(7) angstrom, R-F(X-ray) = 0.022, R-F(neutron) = 0.057). The ab planes in the structure are tessellated with distorted pentagonal loops built up by three tetrahedrally coordinated Fe sites and two octahedrally coordinated Fe/Cr sites, linked together in the ab plane by corner-sharing forming a pentagonal Cairo lattice. Magnetic susceptibility measurements and powder neutron diffraction show that the compounds order antiferromagnetically (AFM) with the Neel temperatures decreasing upon increasing the Cr content from T-N similar to 250 K for x = 0 to T-N similar to 155 K for x = 1.2. The magnetic structure of Bi2Fe3CrO9 at T = 30 K is characterized by a propagation vector k = (1/2,1/2,1/2). The tetrahedrally coordinated Fe cations form singlet pairs within dimers of corner-sharing tetrahedra, but spins on the neighboring dimers are nearly orthogonal. The octahedrally coordinated (Fe, Cr) cations form antiferromagnetic up-up-down-down chains along c, while the spin arrangement in the ab plane is nearly orthogonal between nearest neighbors and collinear between second neighbors. The resulting magnetic structure is remarkably different from the one in pure Bi2Fe4O9 and features several types of spin correlations even on crystallographically equivalent exchange that may be caused by the simultaneous presence of Fe and Cr on the octahedral site.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000367614700041 Publication Date 2015-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0300-9246; 1477-9226; 1472-7773 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:131095 Serial 4257
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Author Tahir, M.; Vasilopoulos, P.; Peeters, F.M.
Title Quantum magnetotransport properties of a MoS2 monolayer Type A1 Journal article
Year 2016 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 93 Issue 93 Pages 035406
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study transport properties of a MoS2 monolayer in the presence of a perpendicular magnetic field B. We derive and discuss its band structure and take into account spin and valley Zeeman effects. Compared to a conventional two-dimensional electron gas, these effects lead to new quantum Hall plateaus and new peaks in the longitudinal resistivity as functions of the magnetic field. The field B leads to a significant enhancement of the spin splitting in the conduction band, to a beating of the Shubnikov-de Haas (SdH) oscillations in the low-field regime, and to their splitting in the high-field regime. The Zeeman fields suppress significantly the beating of the SdH oscillations in the low-field regime and strongly enhance their splitting at high fields. The spin and valley polarizations show a similar beating pattern at low fields and are clearly separated at high fields in which they attain a value higher than 90%.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos (up) 000367663500003 Publication Date 2016-01-05
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 42 Open Access
Notes ; This work was supported by the Canadian NSERC Grant No. OGP0121756 (M.T., P.V.) and by the Flemish Science Foundation (FWO-Vl) (F.M.P.). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:131093 Serial 4233
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Author Monico, L.; Janssens, K.; Hendriks, E.; Vanmeert, F.; van der Snickt, G.; Cotte, M.; Falkenberg, G.; Brunetti, B.G.; Miliani, C.
Title Evidence for degradation of the chrome yellows in Van Gogh's sunflowers : a study using noninvasive in situ methods and synchrotron-radiation-based x-ray techniques Type A1 Journal article
Year 2015 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 54 Issue 47 Pages 13923-13927
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This paper presents firm evidence for the chemical alteration of chrome yellow pigments in Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam). Noninvasive in situ spectroscopic analysis at several spots on the painting, combined with synchrotron-radiation-based X-ray investigations of two microsamples, revealed the presence of different types of chrome yellow used by Van Gogh, including the lightfast PbCrO4 and the sulfur-rich PbCr1-xSxO4 (x approximate to 0.5) variety that is known for its high propensity to undergo photoinduced reduction. The products of this degradation process, i.e., Cr-III compounds, were found at the interface between the paint and the varnish. Selected locations of the painting with the highest risk of color modification by chemical deterioration of chrome yellow are identified, thus calling for careful monitoring in the future.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000367722500009 Publication Date 2015-10-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited 24 Open Access
Notes ; We acknowledge financial support from the Italian MIUR project SICH-PRIN (2010329WPF_001) and BELSPO (Brussels) Project S2-ART (SD04A), GOA “SOLARPAINT” (Research Fund Antwerp University, BOF-2015), and FWO (Brussels) projects G.0C12.13, G.0704.08, G.01769.09. We thank ESRF (EC-1051, HG-26) and DESY (I-20120312 EC) for beamtime grants received. Noninvasive analysis of Sunflowers were supported by the EU FP7 programme CHARISMA (Grant 228330) and the Fund Inbev-Baillet Latour (Brussels). L.M. acknowledges financial support from the CNR Short Term Mobility Programme-2013. We thank Muriel Geldof, Luc Megens, Suzan de Groot (The Netherlands Cultural Heritage Agency, RCE), Chiara Grazia, David Buti (CNR-ISTM and SMAArt Centre), and the staff of the Van Gogh Museum for their collaboration. ; Approved Most recent IF: 11.994; 2015 IF: 11.261
Call Number UA @ admin @ c:irua:131110 Serial 5617
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Author Batuk, D.; Batuk, M.; Tsirlin, A.A.; Hadermann, J.; Abakumov, A.M.
Title Trapping of Oxygen Vacancies at Crystallographic Shear Planes in Acceptor-Doped Pb-Based Ferroelectrics Type A1 Journal article
Year 2015 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 54 Issue 54 Pages 14787-14790
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The defect chemistry of the ferroelectric material PbTiO3 after doping with Fe(III) acceptor ions is reported. Using advanced transmission electron microscopy and powder X-ray and neutron diffraction, we demonstrate that even at concentrations as low as circa 1.7% (material composition approximately ABO2.95), the oxygen vacancies are trapped into extended planar defects, specifically crystallographic shear planes. We investigate the evolution of these defects upon doping and unravel their detailed atomic structure using the formalism of superspace crystallography, thus unveiling their role in nonstoichiometry in the Pb-based perovskites.
Address Chemistry Department, Moscow State University, 119991, Moscow (Russia). artem.abakumov@uantwerpen.be
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos (up) 000367723400031 Publication Date 2015-10-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited 3 Open Access
Notes A.M.A. is grateful to the Russian Science Foundation (grant 14-13-00680). AT was funded by the Mobilitas grant MTT77 of the ESF and by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of Alexander von Humboldt Foundation. Approved Most recent IF: 11.994; 2015 IF: 11.261
Call Number c:irua:131104 Serial 4080
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Author Monico, L.; Janssens, K.; Cotte, M.; Sorace, L.; Vanmeert, F.; Brunetti, B.G.; Miliani, C.
Title Chromium speciation methods and infrared spectroscopy for studying the chemical reactivity of lead chromate-based pigments in oil medium Type A1 Journal article
Year 2016 Publication Microchemical journal T2 – TECHNART Conference, APR 27-30, 2015, Catania, ITALY Abbreviated Journal Microchem J
Volume 124 Issue Pages 272-282
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Environmental factors, such as light, humidity and temperature are triggering agents for the alteration of organic and/or inorganic constituents of oil paintings. The oxidation of the organic material is favored by increasing of relative humidity and temperature, whereas processes involving changes of the oxidation states of a number of inorganic pigments (e.g., vermilion, cadmium yellows, zinc yellows, chrome yellows) are mainly activated by light-exposure. In view of the optimization of the long-term conservation and restoration strategies of paintings it is of relevant interest to establish the consequences of thermal parameters (temperature and relative humidity) on the chemical/photochemical-reactivity and the nature of the alteration products of light sensitive-pigments in oil medium. To this aim here we propose a multi-method analytical approach based on the combination of diffuse reflectance UV-Vis, FTIR, synchrotron radiation (SR)-based micro X-ray fluorescence (mu-XRF)/micro-X-ray absorption neat edge structure ()CANES) and electron paramagnetic resonance (EPR) spectroscopies for studying the effects of different relative humidity conditions before and after light exposure on the reactivity of a series of lead chromate-based pigments [such as PbCrO4 center dot PbO (monoclinic), PbCrO4 (monoclinic) and PbCr0.2S0.8O4 (orthorhombic)] in an oil medium. The investigation of paint models was also compared to that of a late 19th century historical orthorhombic PbCr0.4S0.6O4 oil paint. Diffuse reflectance UV-Vis and FTIR spectroscopies were used to obtain information associated with chromatic changes and the formation of organo-metal degradation products at the paint surface. SR-based Cr K-edge mu-XANES/mu-XRF mapping analysis and EPR spectroscopy were employed in a complementary fashion to determine the amount, nature and distribution of Cr(III) and Cr(V)-based alteration compounds within the paints with micrometric spatial resolution. Under the employed thermal aging conditions, lead(II)-carboxylates and reduced Cr-compounds (in abundance of up to about 35% at the surface) have been identified in the lead chromate-based paints. The tendency of chromates to become reduced increased with increasing moisture levels and was favored for the orthorhombic PbCr0.2S0.8O4 compounds. The redox process gave rise to the formation of Cr(V)-species in relative amount much higher than that was formed in the equivalent paint which was exposed only to light. After light-exposure of the thermally aged paints, compounds ascribable to the oxidation of the organic binder were detected for all the types of pigments. Nevertheless, the previous thermal treatment increased the tendency toward photo-reduction of only the PbCr0.2S0.8O4 pigment. For this light-sensitive compound, the thickness variation of the reduced Cr-rich (ca. 70%) photo-alteration layer with moisture levels could be ascribed to a surface passivation phenomenon that had already occurred before photochemical aging. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000367755600042 Publication Date 2015-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 23 Open Access
Notes ; ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:131099 Serial 5519
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Author van der Snickt, G.; Legrand, S.; Caen, J.; Vanmeert, F.; Alfeld, M.; Janssens, K.
Title Chemical imaging of stained-glass windows by means of macro X-ray fluorescence (MA-XRF) scanning Type A1 Journal article
Year 2016 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 124 Issue Pages 615-622
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Since the recent development of a mobile setup, MA-XRF scanning proved a valuable tool for the non-invasive, technical study of paintings. In this work, the applicability of MA-XRF scanning for investigating stained-glass windows inside a conservation studio is assessed by analysis of a high-profile, well-studied late-mediaeval panel. Although accurate quantification of components is not feasible with this analytical imaging technique, plotting the detected intensities of K versus Ca in a scatter plot allowed distinguishing glass fragments of different compositional types within the same panel. In particular, clusters in the Ca/K correlation plot revealed the presence of two subtypes of potash glass and three subtypes of high lime low alkali glass. MA-XRF results proved consistent with previous quantitative SEM-EDX analysis on two samples and analytical-based theories on glass production in the Low Countries formulated in literature. A bi-plot of the intensities of the more energetic Rb-K versus Sr-K emission lines yielded a similar glass type differentiation and is here presented as suitable alternative in case the Ca/K signal ratio is affected by superimposed weathering crusts. Apart from identification of the chromophores responsible for the green, blue and red glass colors, contrasting the associated elemental distribution maps obtained on the exterior and interior side of the glass permitted discriminating between colored pot metal glass and multi-layered flashed glass as well. Finally, the benefit of obtaining compositional information from the entire surface, as opposed to point analysis, was illustrated by the discovery of what appears to be a green cobalt glass a feature that was previously missed on this well-studied stained-glass window, both by connoisseurs and spectroscopic sample analysis. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000367755600074 Publication Date 2015-10-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 22 Open Access
Notes ; The staff of the Museums of the City of Bruges, i.e. Director Till-Holger Borchert and Deputy Curator Kristel Van Audenaeren, are acknowledged for this pleasant collaboration and the authorization for the publication of the images in this article. This research was supported by the InBev-Baillet Latour fund. ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:131100 Serial 5514
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Author Ricciardi, P.; Legrand, S.; Bertolotti, G.; Janssens, K.
Title Macro X-ray fluorescence (MA-XRF) scanning of illuminated manuscript fragments: potentialities and challenges Type A1 Journal article
Year 2016 Publication Microchemical journal T2 – TECHNART Conference, APR 27-30, 2015, Catania, ITALY Abbreviated Journal Microchem J
Volume 124 Issue Pages 785-791
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Macro X-ray fluorescence scanning (MA-XRF) is gradually becoming an established technique for the non-invasive analytical investigation of painted surfaces. This paper discusses some of the benefits and limitations of employing MA-XRF for the study of manuscript illuminations. Art historical research on this type of artefacts that is based on scientific measurements is often limited by the fact that usually no sampling can take place. Hence there is a need for non-invasive analytical tools that make it possible to conduct systematic investigations. As a representative example of this type of objects, a 15th century Italian manuscript fragment from the collection of the Fitzwilliam Museum in Cambridge (UK) is investigated. The aims of the study were to gain insight into the materials and techniques employed by Renaissance illuminators and to help answer specific questions regarding the fragment's authorship and geographic origin. The complementarity and advantages of MA-XRF mapping versus site-specific analyses are discussed. For this purpose, MA-XRF data are evaluated and compared with the results of other analytical techniques. The interpretation of the elemental maps is discussed along with the challenges faced during the analysis. (C) 2015 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000367755600096 Publication Date 2015-10-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 24 Open Access
Notes ; ; Approved Most recent IF: 3.034
Call Number UA @ admin @ c:irua:144767 Serial 5698
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Author Van de Walle, E.; Van Nieuwenhove, I.; Vanderleyden, E.; Declercq, H.; Gellynck, K.; Schaubroeck, D.; Ottevaere, H.; Thienpont, H.; De Vos, W.H.; Cornelissen, M.; Van Vlierberghe, S.; Dubruel, P.
Title Polydopamine-gelatin as universal cell-interactive coating for methacrylate-based medical device packaging materials : when surface chemistry overrules substrate bulk properties Type A1 Journal article
Year 2016 Publication Biomacromolecules Abbreviated Journal
Volume 17 Issue 1 Pages 56-68
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Despite its widespread application in the fields of ophthalmology, orthopedics and dentistry and the stringent need for polymer packagings that induce in vivo tissue integration, the full potential of poly(methyl methacrylate) (PMMA) and its derivatives as medical device packaging material has not been explored yet. We therefore elaborated on the development of a universal coating for methacrylate-based materials which ideally should reveal cell-interactivity irrespective of the polymer substrate bulk properties. Within this perspective, the present work reports on the UV-induced synthesis of PMMA and its more flexible poly(ethyleneglycol) (PEG)-based derivative (PMMAPEG) and its subsequent surface decoration using polydopamine (PDA) as well as PDA combined with gelatin B (Gel B). Successful application of both layers was confirmed by multiple surface characterization techniques. The cell interactivity of the materials was studied by performing live-dead assays and immunostainings of the cytoskeletal components of fibroblasts. It can be concluded that only the combination of PDA and Gel B yields materials posessing similar cell interactivities, irrespective of the physicochemical properties of the underlying substrate. The proposed coating outperforms both the PDA functionalized and the pristine polymer surfaces. A universal cell-interactive coating for methacrylate-based medical device packaging materials has thus been realized.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368047800007 Publication Date 2015-11-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1525-7797 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:129159 Serial 8393
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Author Brito, B.G.A.; Candido, L.; Hai, G.-Q.; Peeters, F.M.
Title Quantum effects in a free-standing graphene lattice : path-integral against classical Monte Carlo simulations Type A1 Journal article
Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 92 Issue 92 Pages 195416
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In order to study quantum effects in a two-dimensional crystal lattice of a free-standing monolayer graphene, we have performed both path-integral Monte Carlo (PIMC) and classical Monte Carlo (MC) simulations for temperatures up to 2000 K. The REBO potential is used for the interatomic interaction. The total energy, interatomic distance, root-mean-square displacement of the atom vibrations, and the free energy of the graphene layer are calculated. The obtained lattice vibrational energy per atom from the classical MC simulation is very close to the energy of a three-dimensional harmonic oscillator 3k(B)T. The PIMC simulation shows that quantum effects due to zero-point vibrations are significant for temperatures T < 1000 K. The quantum contribution to the lattice vibrational energy becomes larger than that of the classical lattice for T < 400 K. The lattice expansion due to the zero-point motion causes an increase of 0.53% in the lattice parameter. A minimum in the lattice parameter appears at T similar or equal to 500 K. Quantum effects on the atomic vibration amplitude of the graphene lattice and its free energy are investigated.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos (up) 000368095400004 Publication Date 2015-11-13
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 22 Open Access
Notes ; This research was supported by the Brazilian agencies FAPESP, FAPEG, and CNPq, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 3.836; 2015 IF: 3.736
Call Number UA @ lucian @ c:irua:131144 Serial 4232
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Author Bertoni, G.; Fabbri, F.; Villani, M.; Lazzarini, L.; Turner, S.; Van Tendeloo, G.; Calestani, D.; Gradečak, S.; Zappettini, A.; Salviati, G.
Title Nanoscale mapping of plasmon and exciton in ZnO tetrapods coupled with Au nanoparticles Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 19168
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Metallic nanoparticles can be used to enhance optical absorption or emission in semiconductors, thanks to a strong interaction of collective excitations of free charges (plasmons) with electromagnetic fields. Herein we present the direct imaging at the nanoscale of plasmon-exciton coupling in Au/ZnO nanostructures by combining scanning transmission electron energy loss and cathodoluminescence spectroscopy and mapping. The Au nanoparticles (~30 nm in diameter) are grown in-situ on ZnO nanotetrapods by means of a photochemical process without the need of binding agents or capping molecules. This results in clean interfaces, enabling to prove the occurrence of the plasmon-exciton coupling and the straightforward mapping of its spatial localization. Interestingly, the Au plasmon resonance is localized at the Au/vacuum interface, rather than presenting an isotropic distribution around the nanoparticle. On the contrary, a strong localization of the ZnO excitons, has been observed inside the Au nanoparticle, revealing the existence of the plasmon-exciton coupling, as also confirmed by numerical simulations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368111900001 Publication Date 2016-01-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 15 Open Access
Notes The research leading to these results has received funding from the European Union FP7 Grant Agreement n. 265073 ITN-Nanowiring, and FP7 Grant Agreement n. 312483 ESTEEM2 for Integrated Infrastructure Initiative – I3. S.T. gratefully acknowledges the FWO Vlaanderen. G.V.T. acknowledges the European Research Council (ERC grant N°246791 – COUNTATOMS). The authors thank Alessandra Catellani and Arrigo Calzolari for helpful discussions.; Esteem2_jra3 Approved Most recent IF: 4.259
Call Number c:irua:130406 c:irua:130406 Serial 3999
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Author Kolev, S.; Bogaerts, A.
Title Similarities and differences between gliding glow and gliding arc discharges Type A1 Journal article
Year 2015 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume 24 Issue 24 Pages 065023
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this work we have analyzed the properties of a gliding dc discharge in argon at atmospheric pressure. Despite the usual designation of these discharges as ‘gliding arc discharges’, it was found previously that they operate in two different regimes—glow and arc. Here we analyze the differences in both regimes by means of two dimensional fluid modeling. In order to address different aspects of the discharge operation, we use two models—Cartesian and axisymmetric in a cylindrical coordinate system. The obtained results show that the two types of discharges produce a similar plasma column for a similar discharge current. However, the different mechanisms of plasma channel attachment to the cathode could produce certain differences in the plasma parameters (i.e. arc elongation), and this can affect gas treatments applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368117100028 Publication Date 2015-11-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252;1361-6595; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 12 Open Access
Notes This work is financially supported by the Methusalem financing and by the IAP/7 (Inter-university Attraction Pole) program ‘Physical Chemistry of Plasma-Surface Interactions’ from the Belgian Federal Office for Science Policy (BELSPO). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen Approved Most recent IF: 3.302; 2015 IF: 3.591
Call Number c:irua:129214 Serial 3952
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Author Sentosun, K.; Sanz Ortiz, M.N.; Batenburg, K.J.; Liz-Marzán, L.M.; Bals, S.
Title Combination of HAADF-STEM and ADF-STEM Tomography for Core-Shell Hybrid Materials Type A1 Journal article
Year 2015 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char
Volume 32 Issue 32 Pages 1063-1067
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Vision lab
Abstract Characterization of core-shell type nanoparticles in 3D by transmission electron microscopy (TEM) can be very challenging. Especially when both heavy and light elements co-exist within the same nanostructure, artefacts in the 3D reconstruction are often present. A representative example would be a particle comprising an anisotropic metallic (Au) nanoparticle coated with a (mesoporous) silica shell. To obtain a reliable 3D characterization of such an object, we propose a dose-efficient strategy to simultaneously acquire high angle annular dark field scanning TEM and annular dark field tilt series for tomography. The 3D reconstruction is further improved by applying an advanced masking and interpolation approach to the acquired data. This new methodology enables us to obtain high quality reconstructions from which also quantitative information can be extracted. This approach is broadly applicable to investigate hybrid core-shell materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368446800003 Publication Date 2015-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0934-0866; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.474 Times cited 13 Open Access OpenAccess
Notes S.B. acknowledges financial support from European Research Council (ERC) (ERC Starting Grant #335078-COLOURATOM). L.M. acknowledges funding from the EU, Grant# 310651-2 Self-Assembly in Confined Space (SACS). K.J.B acknowledges financial support from the Netherlands Organisation for Scientific Research (NWO), project number 639.072.005 and NWO CW 700.57.026. Networking support was provided by COST Action MP1207. The authors acknowledge the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 for financial support.; esteem2jra4; ECASSara; (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); Approved Most recent IF: 4.474; 2015 IF: 3.081
Call Number c:irua:129590 c:irua:129590 Serial 3967
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Author Cabral, L.R.E.; de Aquino, B.R.C.H.T.; de Souza Silva, C.C.; Milošević, M.V.; Peeters, F.M.
Title Two-shell vortex and antivortex dynamics in a Corbino superconducting disk Type A1 Journal article
Year 2016 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 93 Issue 93 Pages 014515
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We examine theoretically the dynamics of two vortex shells in pinning-free superconducting thin disks in the Corbino geometry. In the first considered case, the inner shell is composed of vortices and the outer one of antivortices, corresponding to a state induced by the stray field of an off-plane magnetic dipole placed on top of the superconductor. In the second considered case, both shells comprise vortices induced by a homogeneous external field. We derive the equation of motion for each shell within the Bardeen-Stephen model and study the dynamics analytically by assuming both shells are rigid and commensurate. In both cases, two distinct regimes for vortex shell motion are identified: For low applied currents the entire configuration rotates rigidly, while above a threshold current the shells decouple from each other and rotate at different angular velocities. Analytical expressions for the decoupling current, the recombination time in the decoupled phases, as well as the voltage-current characteristics are presented. Our analytical results are in excellent agreement with numerical molecular dynamics simulations of the full many-vortex problem.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos (up) 000368481600003 Publication Date 2016-01-25
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 7 Open Access
Notes ; This work was supported by the Brazilian Science Agencies CAPES, CNPq, and FACEPE under Grants No. APQ-1381-1.05/12, No. APQ 2017-1.05/12, and No. APQ-0598/1.05-08 and by EU-COST Action No. MP1201 and the Research Foundation-Flanders (FWO). ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:131541 Serial 4270
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Author Khalilov, U.; Yusupov, M.; Bogaerts, A.; Neyts, E.C.
Title Selective Plasma Oxidation of Ultrasmall Si Nanowires Type A1 Journal article
Year 2016 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 120 Issue 120 Pages 472-477
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Device performance of Si|SiOx core-shell based nanowires critically depends on the exact control over the oxide thickness. Low-temperature plasma oxidation is a highly promising alternative to thermal oxidation allowing for improved control over the oxidation process, in particular for ultrasmall Si nanowires. We here elucidate the room temperature plasma oxidation mechanisms of ultrasmall Si nanowires using hybrid molecular dynamics / force-bias Monte Carlo simulations. We demonstrate how the oxidation and concurrent water formation mechanisms are a function of the oxidizing plasma species and we demonstrate how the resulting core-shell oxide thickness can be controlled through these species. A new mechanism of water formation is discussed in detail. The results provide a detailed atomic level explanation of the oxidation process of highly curved Si surfaces. These results point out a route toward plasma-based formation of ultrathin core-shell Si|SiOx nanowires at room temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368562200057 Publication Date 2015-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 3 Open Access
Notes U.K. and M.Y. gratefully acknowledge financial support from the Research Foundation – Flanders (FWO), Grants 12M1315N and 1200216N. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. We thank Prof. A. C. T. van Duin for sharing the ReaxFF code. Approved Most recent IF: 4.536
Call Number c:irua:130677 Serial 4002
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Author Van Aert, S.; De Backer, A.; Martinez, G.T.; den Dekker, A.J.; Van Dyck, D.; Bals, S.; Van Tendeloo, G.
Title Advanced electron crystallography through model-based imaging Type A1 Journal article
Year 2016 Publication IUCrJ Abbreviated Journal Iucrj
Volume 3 Issue 3 Pages 71-83
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab; Engineering Management (ENM)
Abstract The increasing need for precise determination of the atomic arrangement of non-periodic structures in materials design and the control of nanostructures explains the growing interest in quantitative transmission electron microscopy. The aim is to extract precise and accurate numbers for unknown structure parameters including atomic positions, chemical concentrations and atomic numbers. For this purpose, statistical parameter estimation theory has been shown to provide reliable results. In this theory, observations are considered purely as data planes, from which structure parameters have to be determined using a parametric model describing the images. As such, the positions of atom columns can be measured with a precision of the order of a few picometres, even though the resolution of the electron microscope is still one or two orders of magnitude larger. Moreover, small differences in average atomic number, which cannot be distinguished visually, can be quantified using high-angle annular dark-field scanning transmission electron microscopy images. In addition, this theory allows one to measure compositional changes at interfaces, to count atoms with single-atom sensitivity, and to reconstruct atomic structures in three dimensions. This feature article brings the reader up to date, summarizing the underlying theory and highlighting some of the recent applications of quantitative model-based transmisson electron microscopy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368590900010 Publication Date 2015-11-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2052-2525; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.793 Times cited 30 Open Access OpenAccess
Notes The authors gratefully acknowledge the Research Foundation Flanders (FWO, Belgium) for funding and for a PhD grant to ADB. The research leading to these results has received funding from the European Union 7th Framework Program (FP7/20072013) under grant agreement No. 312483 (ESTEEM2). SB and GVT acknowledge the European Research Council under the 7th Framework Program (FP7), ERC grant No. 335078 – COLOURATOMS and ERC grant No. 246791 – COUNTATOMS.; esteem2jra2; ECASSara; (ROMEO:green; preprint:; postprint:can ; pdfversion:can); Approved Most recent IF: 5.793
Call Number c:irua:129589 c:irua:129589 Serial 3965
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Author van der Snickt, G.; Martins, A.; Delaney, J.; Janssens, K.; Zeibel, J.; Duffy, M.; McGlinchey, C.; Van Driel, B.; Dik, J.
Title Exploring a hidden painting below the surface of Rene Magritte's Le Portrait Type A1 Journal article
Year 2016 Publication Applied spectroscopy Abbreviated Journal Appl Spectrosc
Volume 70 Issue 1 Pages 57-67
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Two state-of-the-art methods for non-invasive visualization of subsurface (or overpainted) pictorial layers present in painted works of art are employed to study Le portrait, painted by Belgian artist Rene Magritte in 1935. X-ray radiography, a commonly used method for the nondestructive inspection of paintings, had revealed the presence of an underlying figurative composition, part of an earlier Magritte painting entitled La pose enchantee (1927) which originally depicted two full length nude female figures with exaggerated facial features. On the one hand, macroscopic X-ray fluorescence analysis (MA-XRF), a method capable of providing information on the distribution of the key chemical elements present in many artists' pigments, was employed. The ability of the X-rays to penetrate the upper layer of paint enabled the imaging of the facial features of the female figure and provided information on Magritte's palette for both surface and hidden composition. On the other hand, visible and near infrared hyperspectral imaging spectroscopies in transmission mode were also used, especially in the area of the table cloth in order to look through the upper representation and reveal the pictorial layer(s) below. MA-XRF provided elemental information on the pigment distributions in both the final painting and the prior whereas the transmission mode provided information related to preparatory sketches as well as revealing differences between the paints used in both compositions. These results illustrate very well the manner in which the two imaging methods complement each other, both in the sense of providing different types of information on the nature and presence of paint components/pigments and in the sense of being optimally suited to easily penetrate through different types of overpaint.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368604500007 Publication Date 2016-01-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-7028 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.529 Times cited 13 Open Access
Notes ; GvdS and KJ acknowledge the support of the Fund Inbev-Baillet Latour. JKD acknowledges support from the Andrew Mellon Foundation and the National Science Foundation. BvD and JD acknowledge support from The Netherlands Organisation for Scientific Research (NWO). ; Approved Most recent IF: 1.529
Call Number UA @ admin @ c:irua:131544 Serial 5620
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Author Calizzi, M.; Venturi, F.; Ponthieu, M.; Cuevas, F.; Morandi, V.; Perkisas, T.; Bals, S.; Pasquini, L.
Title Gas-phase synthesis of Mg-Ti nanoparticles for solid-state hydrogen storage Type A1 Journal article
Year 2016 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 18 Issue 18 Pages 141-148
Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT)
Abstract Mg-Ti nanostructured samples with different Ti contents were prepared via compaction of nanoparticles grown by inert gas condensation with independent Mg and Ti vapour sources. The growth set-up offered the option to perform in situ hydrogen absorption before compaction. Structural and morphological characterisation was carried out by X-ray diffraction, energy dispersive spectroscopy and electron microscopy. The formation of an extended metastable solid solution of Ti in hcp Mg was detected up to 15 at% Ti in the as-grown nanoparticles, while after in situ hydrogen absorption, phase separation between MgH2 and TiH2 was observed. At a Ti content of 22 at%, a metastable Mg-Ti-H fcc phase was observed after in situ hydrogen absorption. The co-evaporation of Mg and Ti inhibited nanoparticle coalescence and crystallite growth in comparison with the evaporation of Mg only. In situ hydrogen absorption was beneficial to subsequent hydrogen behaviour, studied by high pressure differential scanning calorimetry and isothermal kinetics. A transformed fraction of 90% was reached within 100 s at 300 degrees C during both hydrogen absorption and desorption. The enthalpy of hydride formation was not observed to differ from bulk MgH2.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos (up) 000368755500014 Publication Date 2015-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 31 Open Access Not_Open_Access
Notes ; Part of this work was supported by the COST Action MP1103 “Nanostructured materials for solid-state hydrogen storage”. ; Approved Most recent IF: 4.123
Call Number UA @ lucian @ c:irua:131589 Serial 4184
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Author Moldovan, D.; Peeters, F.M.
Title Strain engineering of the electronic properties of bilayer graphene quantum dots: Strain engineering of the electronic properties of bilayer graphene quantum dots Type A1 Journal article
Year 2015 Publication Physica status solidi: rapid research letters Abbreviated Journal Phys Status Solidi-R
Volume 10 Issue 10 Pages 39-45
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the effect of mechanical deformations on the elec- tronic properties of hexagonal flakes of bilayer graphene. The behavior of electrons induced by triaxial strain can be de- scribed by an effective pseudo-magnetic field which is homo- geneous in the center of the flake. We find that in-plane strain, applied to both layers equally, can break the layer symmetry leading to different behavior in the top and bottom layers of graphene. At low energy, just one of the layers feels

the pseudo-magnetic field: the zero-energy pseudo-Landau level is missing in the second layer, thus creating a gap be- tween the lowest non-zero levels. While the layer asymmetry is most significant at zero energy, interaction with the edges of the flake extends the effect to higher pseudo-Landau lev- els. The behavior of the top and bottom layers may be re- versed by rotating the triaxial strain by 60°.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368814500005 Publication Date 2015-08-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6254; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.032 Times cited 9 Open Access
Notes This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. Approved Most recent IF: 3.032; 2015 IF: 2.142
Call Number c:irua:129592 Serial 3970
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Author Turner, S.; Idrissi, H.; Sartori, A.F.; Korneychuck, S.; Lu, Y.-G.; Verbeeck, J.; Schreck, M.; Van Tendeloo, G.
Title Direct imaging of boron segregation at dislocations in B:diamond heteroepitaxial films Type A1 Journal article
Year 2016 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 8 Issue 8 Pages 2212-2218
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A thin film of heavily B-doped diamond has been grown epitaxially by microwave plasma chemical vapor deposition on an undoped diamond layer, on top of a Ir/YSZ/Si(001) substrate stack, to study the boron segregation and boron environment at the dislocations present in the film. The density and nature of the dislocations were investigated by conventional and weak-beam dark-field transmission electron microscopy techniques, revealing the presence of two types of dislocations: edge and mixed-type 45 degrees dislocations. The presence and distribution of B in the sample was studied using annular dark-field scanning transmission electron microscopy and spatially resolved electron energy-loss spectroscopy. Using these techniques, a segregation of B at the dislocations in the film is evidenced, which is shown to be intermittent along the dislocation. A single edge-type dislocation was selected to study the distribution of the boron surrounding the dislocation core. By imaging this defect at atomic resolution, the boron is revealed to segregate towards the tensile strain field surrounding the edge-type dislocations. An investigation of the fine structure of the B-K edge at the dislocation core shows that the boron is partially substitutionally incorporated into the diamond lattice and partially present in a lower coordination (sp(2)-like hybridization).
Address EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. stuart.turner@uantwerpen.be
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos (up) 000368860900053 Publication Date 2015-12-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 15 Open Access
Notes S. T. acknowledges the fund for scien tific research Flanders (FWO) for a post-doctoral scholarship and under contract number G.0044.13N Approved Most recent IF: 7.367
Call Number c:irua:131597UA @ admin @ c:irua:131597 Serial 4121
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Author Cai, H.; Kang, J.; Sahin, H.; Chen, B.; Suslu, A.; Wu, K.; Peeters, F.; Meng, X.; Tongay, S.
Title Exciton pumping across type-I gallium chalcogenide heterojunctions Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume 27 Issue 27 Pages 065203
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Quasi-two-dimensional gallium chalcogenide heterostructures are created by transferring exfoliated few-layer GaSe onto bulk GaTe sheets. Luminescence spectroscopy measurements reveal that the light emission from underlying GaTe layers drastically increases on heterojunction regions where GaSe layers make contact with the GaTe. Density functional theory (DFT) and band offset calculations show that conduction band minimum (CBM) (valance band maximum (VBM)) values of GaSe are higher (lower) in energy compared to GaTe, forming type-I band alignment at the interface. Consequently, GaSe layers provide photo-excited electrons and holes to GaTe sheets through relatively large built-in potential at the interface, increasing overall exciton population and light emission from GaTe. Observed results are not specific to the GaSe/GaTe system but observed on GaS/GaSe heterolayers with type-I band alignment. Observed experimental findings and theoretical studies provide unique insights into interface effects across dissimilar gallium chalcogenides and offer new ways to boost optical performance by simple epitaxial coating.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos (up) 000368897100008 Publication Date 2016-01-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 15 Open Access
Notes ; This work was supported by the Arizona State University seeding program, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of the John M Cowley Center for High Resolution Electron Microscopy at Arizona State University. The authors thank Anupum Pant for useful discussions. We gratefully acknowledge the use of the facilities at the LeRoy Eyring Center for Solid State Science at Arizona State University. S Tongay acknowledges support from DMR-1552220. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:131570 Serial 4179
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Author Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Kaunisto, K.; Sada, C.; Turner, S.; Gönüllü, Y.; Ruoko, T.-P.; Borgese, L.; Bontempi, E.; Van Tendeloo, G.; Lemmetyinen, H.; Mathur, S.
Title Fe2O3-TiO2Nano-heterostructure Photoanodes for Highly Efficient Solar Water Oxidation Type A1 Journal article
Year 2015 Publication Advanced Materials Interfaces Abbreviated Journal Adv Mater Interfaces
Volume 2 Issue 2 Pages 1500313
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Harnessing solar energy for the production of clean hydrogen by photo­electrochemical water splitting represents a very attractive, but challenging approach for sustainable energy generation. In this regard, the fabrication of Fe2O3–TiO2 photoanodes is reported, showing attractive performances [≈2.0 mA cm−2 at 1.23 V vs. the reversible hydrogen electrode in 1 M NaOH] under simulated one-sun illumination. This goal, corresponding to a tenfold photoactivity enhancement with respect to bare Fe2O3, is achieved by atomic layer deposition of TiO2 over hematite (α-Fe2O3) nanostructures fabricated by plasma enhanced-chemical vapor deposition and final annealing at 650 °C. The adopted approach enables an intimate Fe2O3–TiO2 coupling, resulting in an electronic interplay at the Fe2O3/TiO2 interface. The reasons for the photocurrent enhancement determined by TiO2 overlayers with increasing thickness are unraveled by a detailed chemico-physical investigation, as well as by the study of photo­generated charge carrier dynamics. Transient absorption spectroscopy shows that the increased photoelectrochemical response of heterostructured photoanodes compared to bare hematite is due to an enhanced separation of photogenerated charge carriers and more favorable hole dynamics for water oxidation. The stable responses obtained even in simulated seawater provides a feasible route in view of the eventual large-scale generation of renewable energy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368914700011 Publication Date 2015-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2196-7350; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.279 Times cited 56 Open Access
Notes The authors kindly acknowledge the fi nancial support under the FP7 project “SOLAROGENIX” (NMP4-SL-2012-310333), as well as Padova University ex-60% 2012–2014 projects, Grant No. CPDR132937/13 (SOLLEONE), and Regione Lombardia-INSTM ATLANTE projects. S.T. acknowledges the FWO Flanders for a postdoctoral scholarship. Approved Most recent IF: 4.279; 2015 IF: NA
Call Number c:irua:129201 Serial 3957
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Author Ozaydin, H.D.; Sahin, H.; Kang, J.; Peeters, F.M.; Senger, R.T.
Title Electronic and magnetic properties of 1T-TiSe2 nanoribbons Type A1 Journal article
Year 2015 Publication 2D materials Abbreviated Journal 2D Mater
Volume 2 Issue 2 Pages 044002
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Motivated by the recent synthesis of single layer TiSe2, we used state-of-the-art density functional theory calculations, to investigate the structural and electronic properties of zigzag and armchair-edged nanoribbons (NRs) of this material. Our analysis reveals that, differing from ribbons of other ultra-thin materials such as graphene, TiSe2 NRs have some distinctive properties. The electronic band gap of the NRs decreases exponentially with the width and vanishes for ribbons wider than 20 angstrom. For ultranarrow zigzag-edged NRs we find odd-even oscillations in the band gap width, although their band structures show similar features. Moreover, our detailed magnetic-ground-state analysis reveals that zigzag and armchair edged ribbons have non-magnetic ground states. Passivating the dangling bonds with hydrogen at the edges of the structures influences the band dispersion. Our results shed light on the characteristic properties of T phase NRs of similar crystal structures.
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Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos (up) 000368936600005 Publication Date 2015-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.937 Times cited 20 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus Short Marie Curie Fellowship. HDO, HS and RTS acknowledge the support from TUBITAK through project 114F397. ; Approved Most recent IF: 6.937; 2015 IF: NA
Call Number UA @ lucian @ c:irua:131602 Serial 4169
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Author Bogaerts, A.; Khosravian, N.; Van der Paal, J.; Verlackt, C.C.W.; Yusupov, M.; Kamaraj, B.; Neyts, E.C.
Title Multi-level molecular modelling for plasma medicine Type A1 Journal article
Year 2016 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 49 Issue 49 Pages 054002
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Modelling at the molecular or atomic scale can be very useful for obtaining a better insight in plasma medicine. This paper gives an overview of different atomic/molecular scale modelling approaches that can be used to study the direct interaction of plasma species with biomolecules or the consequences of these interactions for the biomolecules on a somewhat longer time-scale. These approaches include density functional theory (DFT), density functional based tight binding (DFTB), classical reactive and non-reactive molecular dynamics (MD) and united-atom or coarse-grained MD, as well as hybrid quantum mechanics/molecular mechanics (QM/MM) methods. Specific examples will be given for three important types of biomolecules, present in human cells, i.e. proteins, DNA and phospholipids found in the cell membrane. The results show that each of these modelling approaches has its specific strengths and limitations, and is particularly useful for certain applications. A multi-level approach is therefore most suitable for obtaining a global picture of the plasma–biomolecule interactions.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368944100003 Publication Date 2015-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 11 Open Access
Notes This work is financially supported by the Fund for Scientific Research Flanders (FWO) and the Francqui Foundation. The calculations were carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. Approved Most recent IF: 2.588
Call Number c:irua:131571 Serial 3985
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Author Kozák, T.; Vlček, J.
Title A parametric model for reactive high-power impulse magnetron sputtering of films Type A1 Journal article
Year 2016 Publication Journal Of Physics D-Applied Physics Abbreviated Journal J Phys D Appl Phys
Volume 49 Issue 49 Pages 055202
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract We present a time-dependent parametric model for reactive HiPIMS deposition of films. Specific features of HiPIMS discharges and a possible increase in the density of the reactive gas in front of the reactive gas inlets placed between the target and the substrate are considered in the model. The model makes it possible to calculate the compound fractions in two target layers and in one substrate layer, and the deposition rate of films at fixed partial pressures of the reactive and inert gas. A simplified relation for the deposition rate of films prepared using a reactive HiPIMS is presented. We used the model to simulate controlled reactive HiPIMS depositions of stoichiometric ZrO2 films, which were recently carried out in our laboratories with two different configurations of the O2 inlets in front of the sputtered target. The repetition frequency was 500 Hz at the deposition-averaged target power densities of 5 Wcm−2 and 50 Wcm−2 with a pulse-averaged target power density up to 2 kWcm−2. The pulse durations were 50 μs and 200 μs. Our model calculations show that the to-substrate O2 inlet provides systematically lower compound fractions in the target surface layer and higher compound fractions in the substrate surface layer, compared with the to-target O2 inlet. The low compound fractions in the target surface layer (being approximately 10% at the depositionaveraged target power density of 50 Wcm−2 and the pulse duration of 200 μs) result in high deposition rates of the films produced, which are in agreement with experimental values.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368944100016 Publication Date 2015-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links
Impact Factor 2.588 Times cited 25 Open Access
Notes This work was supported by the Czech Science Foundation under Project No. GA14–03875S Approved Most recent IF: 2.588
Call Number PLASMANT @ plasmant @ Serial 3994
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Author Fedotov, S.S.; Khasanova, N.R.; Samarin, A.S.; Drozhzhin, O.A.; Batuk, D.; Karakulina, O.M.; Hadermann, J.; Abakumov, A.M.; Antipov, E.V.
Title AVPO4F (A = Li, K): A 4 V Cathode Material for High-Power Rechargeable Batteries Type A1 Journal article
Year 2016 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 28 Issue 28 Pages 411-415
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A novel potassium-based fluoride-phosphate, KVPO4F, with a KTiOPO4 (KTP) type structure is synthesized and characterized. About 85% of potassium has been electrochemically extracted on oxidation producing a cathode material with attractive performance for Li-ion batteries. The material operates at the electrode potential near 4V vs Li/Li+ exhibiting a sloping voltage profile, extremely low polarization, small volume change of about 2% and excellent rate capability, maintaining more than 75% of the initial capacity at 40C discharge rate without significant fading.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000368949900002 Publication Date 2016-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 46 Open Access
Notes The authors kindly thank Dr. S. N. Putilin for XRD measurements, Dr. O. A. Shlyakhtin for the assistance in cryochemical synthesis, Ph.D. students A. A. Sadovnikov and E. A. Karpukhina for SEM imaging and FTIR spectra respectively. The work was partly supported by Russian Science Foundation (grant 16-19-00190), Skoltech Center for Electrochemical Energy Storage and Moscow State University Devel-opment Program up to 2020. J. Hadermann, O.M. Karakulina and A.M. Abakumov acknowledge support from FWO under grant G040116N. Approved Most recent IF: 9.466
Call Number c:irua:131583 Serial 4001
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