toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Gélard, J.; Jehanathan, N.; Roussel, H.; Gariglio, S.; Lebedev, O.I.; Van Tendeloo, G.; Dubourdieu, C. pdf  doi
openurl 
  Title Off-stoichiometry effects on the crystalline and defect structure of hexagonal manganite REMnO3 films (RE = Y, Er, Dy) Type A1 Journal article
  Year 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 23 Issue (up) 5 Pages 1232-1238  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The crystalline and defect structure of epitaxial hexagonal RExMnyO3 (RE = Er, Dy) films with varying cationic composition was investigated by X-ray diffraction and transmission electron microscopy. The films are composed of a strained layer at the interface with the substrate and of a relaxed layer on top of it. The critical thickness is of 10 to 25 nm. For Mn-rich films (or RE deficient), an off-stoichiometric composition maintaining the hexagonal LuMnO3-type structure is stabilized over a large range of the RE/Mn ratio (0.72−1.00), with no Mn-rich secondary phases observed. A linear dependence of the out-of-plane lattice parameter with RE/Mn is observed in this range. Out-of-phase boundary (OPB) extended defects are observed in all films and exhibit a local change in stoichiometry. Such a large solubility limit in the RE deficient region points toward the formation of vacancies on the RE site (RExMnO3−δ, with 0.72 ≤ x < 1), a phenomenon that is encountered in perovskite manganites such as LaxMnO3−δ (x < 1) and that may strongly impact the physical properties of hexagonal manganites.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000287767200022 Publication Date 2011-02-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 17 Open Access  
  Notes Approved Most recent IF: 9.466; 2011 IF: 7.286  
  Call Number UA @ lucian @ c:irua:88649 Serial 2430  
Permanent link to this record
 

 
Author Heidari Mezerji, H.; van den Broek, W.; Bals, S. pdf  doi
openurl 
  Title A practical method to determine the effective resolution in incoherent experimental electron tomography Type A1 Journal article
  Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy  
  Volume 111 Issue (up) 5 Pages 330-336  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract It is not straightforward to determine resolution for a 3D reconstruction when performing an electron tomography experiment. Different contributions such as missing wedge and misalignment add up and often influence the final resolution in an anisotropic manner. The conventional resolution measures can not be used for all of the reconstruction techniques, especially for iterative techniques which are more commonly used for electron tomography in materials science. Here we define a quantitative resolution measure that determines the resolution in three orthogonal directions of the reconstruction. As an application we use this measure to determine the optimum number of simultaneous iterative reconstruction technique (SIRT) iterations to reconstruct the gold nanoparticles, based on a high angle annular dark field STEM (HAADF-STEM) tilt series.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000289396900005 Publication Date 2011-01-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.843 Times cited 26 Open Access  
  Notes Esteem 026019; Fwo Approved Most recent IF: 2.843; 2011 IF: 2.471  
  Call Number UA @ lucian @ c:irua:87606 Serial 2688  
Permanent link to this record
 

 
Author Peelaers, H.; Hernández-Nieves, A.D.; Leenaerts, O.; Partoens, B.; Peeters, F.M. doi  openurl
  Title Vibrational properties of graphene fluoride and graphane Type A1 Journal article
  Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 98 Issue (up) 5 Pages 051914  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The vibrational properties of graphene fluoride and graphane are studied using ab initio calculations. We find that both sp(3) bonded derivatives of graphene have different phonon dispersion relations and phonon densities of states as expected from the different masses associated with the attached atoms of fluorine and hydrogen, respectively. These differences manifest themselves in the predicted temperature behavior of the constant-volume specific heat of both compounds. (C) 2011 American Institute of Physics. [doi:10.1063/1.3551712]  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000286988400027 Publication Date 2011-02-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 66 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-V1), the Belgian Science Policy (IAP), and the collaborative project FWO-MINCyT (Contract No. FW /08/01). A.D.H.-N. is also supported by ANPCyT (under Grant No. PICT2008-2236) ; Approved Most recent IF: 3.411; 2011 IF: 3.844  
  Call Number UA @ lucian @ c:irua:105604 Serial 3844  
Permanent link to this record
 

 
Author Chaves, A.; Peeters, F.M.; Farias, G.A.; Milošević, M.V. url  doi
openurl 
  Title Vortex-vortex interaction in bulk superconductors : Ginzburg-Landau theory Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 83 Issue (up) 5 Pages 054516-054516,14  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The vortex-vortex interaction potential in bulk superconductors is calculated within the Ginzburg-Landau (GL) theory and is obtained from a numerical solution of a set of two coupled nonlinear GL differential equations for the vector potential and the superconducting order parameter, where the merger of vortices into a giant vortex is allowed. Further, the interaction potentials between a vortex and a giant vortex and between a vortex and an antivortex are obtained for both type-I and type-II superconductors. Our numerical results agree asymptotically with the analytical expressions for large intervortex separations that are available in the literature. We propose empirical expressions valid over the full interaction range, which are fitted to our numerical data for different values of the GL parameter.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000287712100009 Publication Date 2011-02-25  
  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 31 Open Access  
  Notes ; Discussions with J. S. Andrade Jr. and A. A. Moreira are gratefully acknowledged. This work was financially supported by CNPq, under Contract No. NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the collaborative project CNPq-FWO-Vl, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:88805 Serial 3899  
Permanent link to this record
 

 
Author de Nolf, W.; Dik, J.; van der Snickt, G.; Wallert, A.; Janssens, K. doi  openurl
  Title High energy X-ray powder diffraction for the imaging of (hidden) paintings Type A1 Journal article
  Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue (up) 5 Pages 910-916  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Over the past few years a number of innovative imaging techniques have been introduced for the visualization of hidden paint layers in Old Master Paintings. These include X-ray fluorescence scanning, TeraHertz imaging, optical coherence tomography and other acoustics-based forms of visualization. All of these techniques are usually a trade-off between their penetrative capability on the one side and their analytical precision in terms of spatial resolution and material identification on the other. Here, we present the first-time use of High-Energy X-ray Powder Diffraction imaging (HE-XRPD) in the study of hidden layers in paintings. As an imaging tool, it combines high-depth sensitivity with fingerprint identification of most inorganic painting materials. The potential as well as some limitations of this technique are demonstrated using model paintings as well as an authentic 16th century painting.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000289731900005 Publication Date 2011-03-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 34 Open Access  
  Notes ; ; Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ admin @ c:irua:89922 Serial 5640  
Permanent link to this record
 

 
Author Alfeld, M.; Janssens, K.; Dik, J.; de Nolf, W.; van der Snickt, G. doi  openurl
  Title Optimization of mobile scanning macro-XRF systems for the in situ investigation of historical paintings Type A1 Journal article
  Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue (up) 5 Pages 899-909  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Elemental distribution maps are of great interest in the study of historical paintings, as they allow to investigate the pigment use of the artist, to image changes made in the painting during or after its creation and in some cases to reveal discarded paintings that were later over painted. Yet a method that allows to record such maps of a broad range of elements in a fast, non-destructive and in situ manner is not yet commonly available; a dedicated mobile scanning XRF instrument might fill this gap. In this paper we present three self-built scanning macro-XRF instruments, each based on the experience gained with its precursor. These instruments are compared in terms of sensitivity and limits of detection, which includes a discussion of the use of polycapillary optics and pinhole collimators as beam defining devices. Furthermore, the imaging capabilities of the instruments are demonstrated in three exemplary cases: (parts of) historical paintings from the 15th to the 19th century are examined. These cases illustrate the value of element specific distribution maps in the study of historical paintings and allow in the case of Vincent van Gogh's Patch of Grass a direct comparison between in situ and synchrotron based scanning macro-XRF.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000289731900004 Publication Date 2011-03-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 107 Open Access  
  Notes ; The investigation of the “Triptych of the Seven Sacraments'' was done in collaboration with Griet Steyaert, independent restorer, and Lizet Klaassen, Royal Museum of Fine Arts (Antwerp, Belgium). The investigation of ”Patch of Grass'' was realized in collaboration with Luuk van der Loeff, Kroller-Muller-Museum (Otterlo, The Netherlands). M. Alfeld is a PhD fellowship of the Research Foundation-Flanders (FWO). This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16) NACHO. The text also presents results of GOA "XANES meets ELNES'' (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0103.04, G.0689.06 and G.0704.08. Further, the work presented was sponsored by the Innovational Research Incentives Scheme of the Netherlands Organization for Scientific Research, NWO (proj. no. 016.118.303). ; Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ admin @ c:irua:89919 Serial 5758  
Permanent link to this record
 

 
Author van der Linden, V.; Meesdom, E.; Devos, A.; van Dooren, R.; Nieuwdorp, H.; Janssen, E.; Balace, S.; Vekemans, B.; Vincze, L.; Janssens, K. doi  openurl
  Title PXRF, \mu-XRF, vacuum \mu-XRF, and EPMA analysis of Email Champlevé objects present in Belgian museums Type A1 Journal article
  Year 2011 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 17 Issue (up) 5 Pages 674-685  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The enamel of 20 Email Champlevé objects dating between the 12th and 19th centuries was investigated by means of microscopic and portable X-ray fluorescence analysis (μ-XRF and PXRF). Seven of these objects were microsampled and the fragments were analyzed with electron probe microanalysis (EPMA) and vacuum μ-XRF to obtain quantitative data about the composition of the glass used to produce these enameled objects. As a result of the evolution of the raw materials employed to produce the base glass, three different compositional groups could be discriminated. The first group consisted of soda-lime-silica glass with a sodium source of mineral origin (with low K content) that was opacified by addition of calcium antimonate crystals. This type of glass was only used in objects made in the 12th century. Email Champlevé objects from the beginning of the 13th century onward were enameled with soda-lime-silica glass with a sodium source of vegetal origin. This type of glass, which has a higher potassium content, was opacified with SnO2 crystals. The glass used for 19th century Email Champlevé artifacts was produced with synthetic and purified components resulting in a different chemical composition compared to the other groups. Although the four analytical techniques employed in this study have their own specific characteristics, they were all found to be suitable for classifying the objects into the different chronological categories.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000295609100005 Publication Date 2011-09-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.891 Times cited 9 Open Access  
  Notes ; ; Approved Most recent IF: 1.891; 2011 IF: 3.007  
  Call Number UA @ admin @ c:irua:92827 Serial 5791  
Permanent link to this record
 

 
Author Janssens, K. doi  openurl
  Title Synchrotron radiation in art and archaeology Type Editorial
  Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue (up) 5 Pages 883-884  
  Keywords Editorial; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000289731900001 Publication Date 2011-04-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 5 Open Access  
  Notes ; ; Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ admin @ c:irua:89918 Serial 5864  
Permanent link to this record
 

 
Author Radepont, M.; de Nolf, W.; Janssens, K.; van der Snickt, G.; Coquinot, Y.; Klaassen, L.; Cotte, M. doi  openurl
  Title The use of microscopic X-ray diffraction for the study of HgS and its degradation products corderoite (\alpha-Hg3S2Cl2), kenhsuite (\gamma-Hg3S2Cl2) and calomel (Hg2Cl2) in historical paintings Type A1 Journal article
  Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue (up) 5 Pages 959-968  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Since antiquity, the red pigment mercury sulfide (α-HgS), called cinnabar in its natural form or vermilion red when synthetic, was very often used in frescoes and paintings, even if it was known to suffer occasionally from degradation. The paint hereby acquires a black or silver-grey aspect. The chemical characterization of these alteration products is rather challenging mainly because of the micrometric size and heterogeneity of the surface layers that develop and that are responsible for the color change. Methods such as electron microscopy, synchrotron-based microscopic X-ray fluorescence, microscopic X-ray absorption near edge spectroscopy, Raman microscopy and secondary ion microscopy have been previously employed to identify the (Hg- and S-) compounds present and to study their co-localization. Next to these, also microscopic X-ray diffraction (XRD) (either by making use of laboratory X-ray sources or when used at a synchrotron facility) allows the identification of the crystal phases that are present in degraded HgS paint layers. In this paper we employ these various forms of micro-XRD to analyze degraded red paint in different paintings and compare the results with other X-ray based methods. Whereas the elemental analyses of the degradation products revealed, next to mercury and sulfur, the presence of chlorine, X-ray diffraction allowed the identification, next to α-HgS, of the Hg and S-containing compound calomel (Hg2Cl2) but also of the Hg, S and Cl-containing minerals corderoite (α-Hg3S2Cl2) and kenhsuite (γ-Hg3S2Cl2). These observations are consistent with X-ray absorption spectroscopy measurements performed at the S- and Cl-edges.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000289731900011 Publication Date 2011-03-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 40 Open Access  
  Notes ; The authors gratefully acknowledge GOA programme “XANES meets EELS'' (University of Antwerp Research Council), the IUAP VI/P16 programme ”Nacho'' (BELSPO, Brussels, Belgium) and FWO (Brussels, Belgium) projects no. G.0689.06, G.0704.08 and G017909N for financial support, the ESRF for granting beamtime under proposals no. EC442 and EC720, and Gema Martinez-Criado for practical help on ID18F. The KMSKA staff is also gratefully acknowledged for their help and interest. Javier Chillida is thanked for providing us with the Pedralbes samples. The authors are also indebted to the CHARISMA project (grant agreement 228330) for financial support. ; Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ admin @ c:irua:89927 Serial 5896  
Permanent link to this record
 

 
Author Potgieter-Vermaak, S.S.; Mmari, A.; Van Grieken, R.; McCrindle, R.I.; Potgieter, J.H. doi  openurl
  Title Degradation of galvanised iron roofing material in Tanzania by atmospheric corrosion Type A1 Journal article
  Year 2011 Publication Corrosion engineering science and technology Abbreviated Journal  
  Volume 46 Issue (up) 5 Pages 642-650  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Galvanised iron is popular in many applications, particular as a roofing material. However, just like other materials, especially metallic ones, it is prone to degradation by corrosion. In this particular study, the degradation of galvanised roof sheets was investigated at a coastal, urban and rural site in Tanzania, Africa. Samples were exposed to various outdoor environments over a period of 3 years. In addition, some accelerated laboratory investigations were conducted in different simulated air pollution environments in an artificial corrosion chamber constructed for this purpose to supplement the outdoor exposure tests. It was found that the combination of the tropical climate and increasing air pollution due to industrial development in the capital Dar-es-Salaam resulted in substantial atmospheric corrosion of the roof sheets, which eventually leads to failure and the necessity for replacement. The rural site had the lowest degree of atmospheric corrosion as expected. A combination of different corrosion products was identified as a result of the atmospheric corrosion by Raman and EDX analyses. The information gained from this investigation could be utilised to construct more durable structures requiring less frequent replacement and maintenance in future.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000294421100008 Publication Date 2010-04-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1478-422x 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:92094 Serial 7758  
Permanent link to this record
 

 
Author Schalm, O.; Cabal, A.; van Espen, P.; Laquière, N.; Storme, P. pdf  doi
openurl 
  Title Improved radiographic methods for the investigation of paintings using laboratory and synchrotron X-ray sources Type A1 Journal article
  Year 2011 Publication Journal of analytical atomic spectrometry Abbreviated Journal  
  Volume 26 Issue (up) 5 Pages 1068-1077  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract It is generally known that radiographic inspection of 1517th century paintings can easily be done with a polychromatic X-ray source using a voltage between 20 kV and 40 kV in combination with classic X-ray films. Unfortunately, the spatial structure of numerous 19th and early 20th century paintings cannot be visualized with conventional radiography due to several reasons such as the use of lead white grounds or low absorbing pigments. Radiographic images are blurred or worse, they do not contain the picture of the painting. During the last decades, many technological innovations have been introduced in the field of radiography but their possibilities in cultural heritage have not been explored in full detail. In our investigation we used phosphor imaging plates, energy dispersive detectors and CCD-cameras in combination with synchrotron radiation and conventional X-ray tubes in order to improve the quality of radiographic images. Several promising techniques that could improve the quality of radiographs of paintings were identified.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000289731900023 Publication Date 2011-04-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477 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:89928 Serial 8070  
Permanent link to this record
 

 
Author Khalilov, U.; Neyts, E.C.; Pourtois, G.; van Duin, A.C.T. doi  openurl
  Title Can we control the thickness of ultrathin silica layers by hyperthermal silicon oxidation at room temperature? Type A1 Journal article
  Year 2011 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 115 Issue (up) 50 Pages 24839-24848  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Using reactive molecular dynamics simulations by means of the ReaxFF potential, we studied the growth mechanism of ultrathin silica (SiO2) layers during hyperthermal oxidation at room temperature. Oxidation of Si(100){2 × 1} surfaces by both atomic and molecular oxygen was investigated in the energy range 15 eV. The oxidation mechanism, which differs from thermal oxidation, is discussed. In the case of oxidation by molecular O2, silica is quickly formed and the thickness of the formed layers remains limited compared to oxidation by atomic oxygen. The Si/SiO2 interfaces are analyzed in terms of partial charges and angle distributions. The obtained structures of the ultrathin SiO2 films are amorphous, including some intrinsic defects. This study is important for the fabrication of silica-based devices in the micro- and nanoelectronics industry, and more specifically for the fabrication of metal oxide semiconductor devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000297947700050 Publication Date 2011-11-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 36 Open Access  
  Notes Approved Most recent IF: 4.536; 2011 IF: 4.805  
  Call Number UA @ lucian @ c:irua:94303 Serial 273  
Permanent link to this record
 

 
Author Yang, X.-Y.; Tian, G.; Chen, L.-H.; Li, Y.; Rooke, J.C.; Wei, Y.-X.; Liu, Z.-M.; Deng, Z.; Van Tendeloo, G.; Su, B.-L. pdf  doi
openurl 
  Title Well-organized zeolite nanocrystal aggregates with interconnected hierarchically micro-meso-macropore systems showing enhanced catalytic performance Type A1 Journal article
  Year 2011 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J  
  Volume 17 Issue (up) 52 Pages 14987-14995  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Preparation and characterization of well-organized zeolitic nanocrystal aggregates with an interconnected hierarchically micromesomacro porous system are described. Amorphous nanoparticles in bimodal aluminosilicates were directly transformed into highly crystalline nanosized zeolites, as well as acting as scaffold template. All pores on three length scales incorporated in one solid body are interconnected with each other. These zeolitic nanocrystal aggregates with hierarchically micromesomacroporous structure were thoroughly characterized. TEM images and 29Si NMR spectra showed that the amorphous phase of the initial material had been completely replaced by nanocrystals to give a micromesomacroporous crystalline zeolitic structure. Catalytic testing demonstrated their superiority due to the highly active sites and the presence of interconnected micromesomacroporosity in the cracking of bulky 1,3,5-triisopropylbenzene (TIPB) compared to traditional zeolite catalysts. This synthesis strategy was extended to prepare various zeolitic nanocrystal aggregates (ZSM-5, Beta, TS-1, etc.) with well-organized hierarchical micromesomacroporous structures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000298547300035 Publication Date 2011-11-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0947-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.317 Times cited 61 Open Access  
  Notes Approved Most recent IF: 5.317; 2011 IF: 5.925  
  Call Number UA @ lucian @ c:irua:96274 Serial 3913  
Permanent link to this record
 

 
Author Molina, L.; Tan, H.; Biermans, E.; Batenburg, K.J.; Verbeeck, J.; Bals, S.; Van Tendeloo, G. pdf  doi
openurl 
  Title Barrier efficiency of sponge-like La2Zr2O7 buffer layers for YBCO-coated conductors Type A1 Journal article
  Year 2011 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 24 Issue (up) 6 Pages 065019-065019,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab  
  Abstract Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different film processing methods can yield similar microstructural features such as nanovoids and nanometer-sized La2Zr2O7 grains. Nanoporosity is a typical feature found in such films and the implications for the functionality of the films are investigated by a combination of scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) and quantitative electron tomography. Chemical solution based La2Zr2O7 films deposited on flexible Ni5 at.%W substrates with a {100}lang001rang biaxial texture were prepared for an in-depth characterization. A sponge-like structure composed of nanometer-sized voids is revealed by high-angle annular dark-field scanning transmission electron microscopy in combination with electron tomography. A three-dimensional quantification of nanovoids in the La2Zr2O7 film is obtained on a local scale. Mostly non-interconnected highly faceted nanovoids compromise more than one-fifth of the investigated sample volume. The diffusion barrier efficiency of a 170 nm thick La2Zr2O7 film is investigated by STEM-EELS, yielding a 1.8 ± 0.2 nm oxide layer beyond which no significant nickel diffusion can be detected and intermixing is observed. This is of particular significance for the functionality of YBa2Cu3O7 − δ coated conductor architectures based on solution derived La2Zr2O7 films as diffusion barriers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000290472900021 Publication Date 2011-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 31 Open Access  
  Notes Esteem 026019; Fwo Approved Most recent IF: 2.878; 2011 IF: 2.662  
  Call Number UA @ lucian @ c:irua:88639UA @ admin @ c:irua:88639 Serial 221  
Permanent link to this record
 

 
Author Philippaerts, A.; Goossens, S.; Vermandel, W.; Tromp, M.; Turner, S.; Geboers, J.; Van Tendeloo, G.; Jacobs, P.A.; Sels, B.F. pdf  doi
openurl 
  Title Design of Ru-zeolites for hydrogen-free production of conjugated linoleic acid Type A1 Journal article
  Year 2011 Publication Chemsuschem Abbreviated Journal Chemsuschem  
  Volume 4 Issue (up) 6 Pages 757-767  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract While conjugated vegetable oils are currently used as additives in the drying agents of oils and paints, they are also attractive molecules for making bio-plastics. Moreover, conjugated oils will soon be accepted as nutritional additives for functional food products. While current manufacture of conjugated vegetable oils or conjugated linoleic acids (CLAs) uses a homogeneous base as isomerisation catalyst, a heterogeneous alternative is not available today. This contribution presents the direct production of CLAs over Ru supported on different zeolites, varying in topology (ZSM-5, BETA, Y), Si/Al ratio and countercation (H+, Na+, Cs+). Ru/Cs-USY, with a Si/Al ratio of 40, was identified as the most active and selective catalyst for isomerisation of methyl linoleate (cis-9,cis-12 (C18:2)) to CLA at 165 °C. Interestingly, no hydrogen pre-treatment of the catalyst or addition of hydrogen donors is required to achieve industrially relevant isomerisation productivities, namely, 0.7 g of CLA per litre of solvent per minute. Moreover, the biologically most active CLA isomers, namely, cis-9,trans-11, trans-10,cis-12 and trans-9,trans-11, were the main products, especially at low catalyst concentrations. Ex situ physicochemical characterisation with CO chemisorption, extended X-ray absorption fine structure measurements, transmission electron microscopy analysis, and temperature-programmed oxidation reveals the presence of highly dispersed RuO2 species in Ru/Cs-USY(40).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000292214000009 Publication Date 2011-04-20  
  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 24 Open Access  
  Notes Fwo Approved Most recent IF: 7.226; 2011 IF: 6.827  
  Call Number UA @ lucian @ c:irua:90352 Serial 660  
Permanent link to this record
 

 
Author Komendová, L.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M. url  doi
openurl 
  Title Different length scales for order parameters in two-gap superconductors : extended Ginzburg-Landau theory Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 84 Issue (up) 6 Pages 064522-064522,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using the Ginzburg-Landau theory extended to the next-to-leading order, we determine numerically the healing lengths of the two order parameters at the two-gap superconductor/normal metal interface. We demonstrate on several examples that those can be different even in the strict domain of applicability of the Ginzburg-Landau theory. This justifies the use of this theory to describe relevant physics of two-gap superconductors, distinguishing them from their single-gap counterparts. The calculational degree of complexity increases only slightly with respect to the conventional Ginzburg-Landau expansion, thus the extended Ginzburg-Landau model remains numerically far less demanding compared to the full microscopic approaches.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000294226000013 Publication Date 2011-08-25  
  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 56 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:92414 Serial 695  
Permanent link to this record
 

 
Author Dixit, H.; Tandon, N.; Cottenier, S.; Saniz, R.; Lamoen, D.; Partoens, B.; van Speybroeck, V.; Waroquier, M. pdf  url
doi  openurl
  Title Electronic structure and band gap of zinc spinel oxides beyond LDA : ZnAl2O4, ZnGa2O4 and ZnIn2O4 Type A1 Journal article
  Year 2011 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 13 Issue (up) 6 Pages 063002-063002,11  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract We examine the electronic structure of the family of ternary zinc spinel oxides ZnX2O4 (X=Al, Ga and In). The band gap of ZnAl2O4 calculated using density functional theory (DFT) is 4.25 eV and is overestimated compared with the experimental value of 3.83.9 eV. The DFT band gap of ZnGa2O4 is 2.82 eV and is underestimated compared with the experimental value of 4.45.0 eV. Since DFT typically underestimates the band gap in the oxide system, the experimental measurements for ZnAl2O4 probably require a correction. We use two first-principles techniques capable of describing accurately the excited states of semiconductors, namely the GW approximation and the modified BeckeJohnson (MBJ) potential approximation, to calculate the band gap of ZnX2O4. The GW and MBJ band gaps are in good agreement with each other. In the case of ZnAl2O4, the predicted band gap values are >6 eV, i.e. ~2 eV larger than the only reported experimental value. We expect future experimental work to confirm our results. Our calculations of the electron effective masses and the second band gap indicate that these compounds are very good candidates to act as transparent conducting host materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000292137500002 Publication Date 2011-06-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1367-2630; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.786 Times cited 98 Open Access  
  Notes Iwt; Fwo; Bof-Noi Approved Most recent IF: 3.786; 2011 IF: 4.177  
  Call Number UA @ lucian @ c:irua:89555 Serial 1008  
Permanent link to this record
 

 
Author Dong, H.M.; Xu, W.; Peeters, F.M. doi  openurl
  Title High-field transport properties of graphene Type A1 Journal article
  Year 2011 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 110 Issue (up) 6 Pages 063704,1-063704,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We present a theoretical investigation on the transport properties of graphene in the presence of high dc driving fields. Considering electron interactions with impurities and acoustic and optical phonons in graphene, we employ the momentum- and energy-balance equations derived from the Boltzmann equation to self-consistently evaluate the drift velocity and temperature of electrons in graphene in the linear and nonlinear response regimes. We find that the current-voltage relation exhibits distinctly nonlinear behavior, especially in the high electric field regime. Under the action of high-fields the large source-drain (sd) current density can be achieved and the current saturation in graphene is incomplete with increasing the sd voltage Vsd up to 3 V. Moreover, for high fields, Vsd>0.1 V, the heating of electrons in graphene occurs. It is shown that the sd current and electron temperature are sensitive to electron density and lattice temperature in the graphene device. This study is relevant to the application of graphene as high-field nano-electronic devices such as graphene field-effect transistors.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000295619300059 Publication Date 2011-09-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 17 Open Access  
  Notes ; This work was supported by the National Natural Science Foundation of China (Grant No. 10974206) and the Department of Science and Technology of Yunnan Province. ; Approved Most recent IF: 2.068; 2011 IF: 2.168  
  Call Number UA @ lucian @ c:irua:93614 Serial 1433  
Permanent link to this record
 

 
Author Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. doi  openurl
  Title Hydrogen impurities and native defects in CdO Type A1 Journal article
  Year 2011 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 110 Issue (up) 6 Pages 063521,1-063521,7  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract We have used first-principles calculations based on density functional theory to study point defects in CdO within the local density approximation and beyond (LDA+U). Hydrogen interstitials and oxygen vacancies are found to act as shallow donors and can be interpreted as the cause of conductivity in CdO. Hydrogen can also occupy an oxygen vacancy in its substitutional form and also acts as a shallow donor. Similar to what was found for ZnO and MgO, hydrogen creates a multicenter bond with its six oxygen neighbors in CdO. The charge neutrality level for native defects and hydrogen impurities has been calculated. It is shown that in the case of native defects, it is not uniquely defined. Indeed, this level depends highly on the chemical potentials of the species and one can obtain different values for different end states in the experiment. Therefore, a comparison with experiment can only be made if the chemical potentials of the species in the experiment are well defined. However, for the hydrogen interstitial defect, since this level is independent of the chemical potential of hydrogen, one can obtain a unique value for the charge neutrality level. We find that the Fermi level stabilizes at 0.43 eV above the conduction band minimum in the case of the hydrogen interstitial defect, which is in good agreement with the experimentally reported value of 0.4 eV.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000295619300041 Publication Date 2011-09-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 13 Open Access  
  Notes ; The authors gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project, the FWO-Vlaanderen through Project G.0191.08 and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC. ; Approved Most recent IF: 2.068; 2011 IF: 2.168  
  Call Number UA @ lucian @ c:irua:93613 Serial 1533  
Permanent link to this record
 

 
Author Verberck, B.; Cambedouzou, J.; Vliegenthart, G.A.; Gompper, G.; Launois, P. doi  openurl
  Title A Monte Carlo study of C70 molecular motion in C70@SWCNT peapods Type A1 Journal article
  Year 2011 Publication Carbon Abbreviated Journal Carbon  
  Volume 49 Issue (up) 6 Pages 2007-2021  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We present Monte Carlo simulations of chains of C70 molecules encapsulated in a single-walled carbon nanotube (SWCNT). For various tube radii R (6.5 Å less-than-or-equals, slant R less-than-or-equals, slant 7.5 Å), we analyze rotational and translational motion of the C70 molecules, as a function of temperature. Apart from reproducing the experimentally well-established lying and standing molecular orientations for small and large tube radii, respectively, we observe, depending on the tube diameter, a variety of molecular motions, orientational flipping of lying molecules, and the migration of molecules resulting in a continual rearrangement of the C70 molecules in clusters of varying lengths. With increasing temperature, the evolution of the pair correlation functions reveals a transition from linear harmonic chain behavior to a hard-sphere liquid, making C70@SWCNT peapods tunable physical realizations of two well-known one-dimensional model systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000288689900025 Publication Date 2011-01-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.337 Times cited 10 Open Access  
  Notes ; Helpful discussions with K.H. Michel, P.-A. Albouy and C. Bousige are greatly acknowledged. This work was financially supported by the Research Foundation – Flanders (FWO-Vl). B.V. is a Postdoctoral Fellow of the Research Foundation Flanders (FWO-VI). ; Approved Most recent IF: 6.337; 2011 IF: 5.378  
  Call Number UA @ lucian @ c:irua:89660 Serial 2201  
Permanent link to this record
 

 
Author Lindner, H.; Bogaerts, A. doi  openurl
  Title Multi-element model for the simulation of inductively coupled plasmas : effects of helium addition to the central gas stream Type A1 Journal article
  Year 2011 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B  
  Volume 66 Issue (up) 6 Pages 421-431  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract A model for an atmospheric pressure inductively coupled plasma (ICP) is developed which allows rather easy extension to a variable number of species and ionisation degrees. This encompasses an easy calculation of transport parameters for mixtures, ionisation and heat capacity. The ICP is modeled in an axisymmetric geometry, taking into account the gas streaming into a flowing ambient gas. A mixture of argon and helium is applied in the injector gas stream as it is often done in laser ablation ICP spectrometry. The results show a strong influence of the added helium on the center of the ICP, which is important for chemical analysis. The length of the central channel is significantly increased and the temperature inside is significantly higher than in the case of pure argon. This means that higher gas volume flow rates can be applied by addition of helium compared to the use of pure argon. This has the advantage that the gas velocity in the transport system towards the ICP can be increased, which allows shorter washout-times. Consequently, shorter measurement times can be achieved, e.g. for spatial mapping analyses in laser ablation ICP spectrometry. Furthermore, the higher temperature and the longer effective plasma length will increase the maximum size of droplets or particles injected into the ICP that are completely evaporated at the detection site. Thus, we expect an increase of the analytical performance of the ICP by helium addition to the injector gas.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000293488700003 Publication Date 2011-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0584-8547; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.241 Times cited 28 Open Access  
  Notes Approved Most recent IF: 3.241; 2011 IF: 2.876  
  Call Number UA @ lucian @ c:irua:90190 Serial 2209  
Permanent link to this record
 

 
Author Idrissi, H.; Turner, S.; Mitsuhara, M.; Wang, B.; Hata, S.; Coulombier, M.; Raskin, J.-P.; Pardoen, T.; Van Tendeloo, G.; Schryvers, D. doi  openurl
  Title Point defect clusters and dislocations in FIB irradiated nanocrystalline aluminum films : an electron tomography and aberration-corrected high-resolution ADF-STEM study Type A1 Journal article
  Year 2011 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal  
  Volume 17 Issue (up) 6 Pages 983-990  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Focused ion beam (FIB) induced damage in nanocrystalline Al thin films has been characterized using advanced transmission electron microscopy techniques. Electron tomography was used to analyze the three-dimensional distribution of point defect clusters induced by FIB milling, as well as their interaction with preexisting dislocations generated by internal stresses in the Al films. The atomic structure of interstitial Frank loops induced by irradiation, as well as the core structure of Frank dislocations, has been resolved with aberration-corrected high-resolution annular dark-field scanning TEM. The combination of both techniques constitutes a powerful tool for the study of the intrinsic structural properties of point defect clusters as well as the interaction of these defects with preexisting or deformation dislocations in irradiated bulk or nanostructured materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge, Mass. Editor  
  Language Wos 000297832300018 Publication Date 2011-10-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.891 Times cited 25 Open Access  
  Notes Iap; Fwo Approved Most recent IF: 1.891; 2011 IF: 3.007  
  Call Number UA @ lucian @ c:irua:93627 Serial 2653  
Permanent link to this record
 

 
Author Tinck, S.; Bogaerts, A.; Shamiryan, D. doi  openurl
  Title Simultaneous etching and deposition processes during the etching of silicon with a Cl2/O2/Ar inductively coupled plasma Type A1 Journal article
  Year 2011 Publication Plasma processes and polymers Abbreviated Journal Plasma Process Polym  
  Volume 8 Issue (up) 6 Pages 490-499  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this article, surface processes occurring during the etching of Si with a Cl2/O2/Ar plasma are investigated by means of experiments and modeling. Cl2-based plasmas are commonly used to etch silicon, while a small fraction of O2 is added to protect the sidewalls from lateral etching during the shallow trench isolation process. When the oxygen fraction exceeds a critical value, the wafer surface process changes from an etching regime to a deposition regime, drastically reducing the etch rate. This effect is commonly referred to as the etch stop phenomenon. To gain better understanding of this mechanism, the oxygen fraction is varied in the gas mixture and special attention is paid to the effects of oxygen and of the redeposition of non-volatile etched species on the overall etch/deposition process. It is found that, when the O2 flow is increased, the etch process changes from successful etching to the formation of a rough surface, and eventually to the actual growth of an oxide layer which completely blocks the etching of the underlying Si. The size of this etch stop island was found to increase as a function of oxygen flow, while its thickness was dependent on the amount of Si etched. This suggests that the growth of the oxide layer mainly depends on the redeposition of non-volatile etch products. The abrupt change in the etch rate as a function of oxygen fraction was not found back in the oxygen content of the plasma, suggesting the competitive nature between oxidation and chlorination at the wafer. Finally, the wafer and reactor wall compositions were investigated by modeling and it was found that the surface rapidly consisted mainly of SiO2 when the O2 flow was increased above about 15 sccm.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Weinheim Editor  
  Language Wos 000292116800003 Publication Date 2011-03-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1612-8850; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.846 Times cited 5 Open Access  
  Notes Approved Most recent IF: 2.846; 2011 IF: 2.468  
  Call Number UA @ lucian @ c:irua:90926 Serial 3014  
Permanent link to this record
 

 
Author Vansweevelt, R.; Mortet, V.; D' Haen, J.; Ruttens, bart; van Haesendonck, C.; Partoens, B.; Peeters, F.M.; Wagner, P. doi  openurl
  Title Study on the giant positive magnetoresistance and Hall effect in ultrathin graphite flakes Type A1 Journal article
  Year 2011 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A  
  Volume 208 Issue (up) 6 Pages 1252-1258  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this paper, we report on the electronic transport properties of mesoscopic, ultrathin graphite flakes with a thickness corresponding to a stack of 150 graphene layers. The graphite flakes show an unexpectedly strong positive magnetoresistance (PMR) already at room temperature, which scales in good approximation with the square of the magnetic field. Furthermore, we show that the resistivity is unaffected by magnetic fields oriented in plane with the graphene layers. Hall effect measurements indicate that the charge carriers are p-type and their concentration increases with increasing temperature while the mobility is decreasing. The Hall voltage is non-linear in higher magnetic fields. Possible origins of the observed effects are discussed. Ball and stick model of the two topmost carbon layers of the hexagonal graphite structure.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000292945800008 Publication Date 2011-02-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1862-6300; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.775 Times cited 8 Open Access  
  Notes ; The authors gratefully acknowledge the support by FWO – Research Foundation Flanders (project G.0159.07 “Structural and electronic properties of biologically modified, graphene-based layers”), by the Federal Belgian Interuniversity Attraction Poles Programme BELSPO (project TAP VI P6/42 “Quantum effects in clusters and nanowires”) and by the Methusalem network “NANO – Antwerp-Hasselt,” funded by the Flemish Community. Technical assistance by Stoffel D. Janssens (magnet calibration and software development), Dr. Hong Yin (AFM-based thickness studies), Dr. Ronald Thoelen (data analysis), and Prof. Hans-Gerd Boyen (XPS spectroscopy) is greatly appreciated. ; Approved Most recent IF: 1.775; 2011 IF: 1.463  
  Call Number UA @ lucian @ c:irua:91941 Serial 3343  
Permanent link to this record
 

 
Author Eckert, M.; Mortet, V.; Zhang, L.; Neyts, E.; Verbeeck, J.; Haenen, ken; Bogaerts, A. pdf  doi
openurl 
  Title Theoretical investigation of grain size tuning during prolonged bias-enhanced nucleation Type A1 Journal article
  Year 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 23 Issue (up) 6 Pages 1414-1423  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this paper, the effects of prolonged bias-enhanced nucleation (prolonged BEN) on the growth mechanisms of diamond are investigated by molecular dynamics (MD) and combined MD-Metropolis Monte Carlo (MD-MMC) simulations. First, cumulative impacts of CxHy+ and Hx+ on an a-C:H/nanodiamond composite were simulated; second, nonconsecutive impacts of the dominant ions were simulated in order to understand the observed phenomena in more detail. As stated in the existing literature, the growth of diamond structures during prolonged BEN is a process that takes place below the surface of the growing film. The investigation of the penetration behavior of CxHy+ and Hx+ species shows that the carbon-containing ions remain trapped within this amorphous phase where they dominate mechanisms like precipitation of sp3 carbon clusters. The H+ ions, however, penetrate into the crystalline phase at high bias voltages (>100 V), destroying the perfect diamond structure. The experimentally measured reduction of grain sizes at high bias voltage, reported in the literature, might thus be related to penetrating H+ ions. Furthermore, the CxHy+ ions are found to be the most efficient sputtering agents, preventing the build up of defective material.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000288291400011 Publication Date 2011-02-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 9 Open Access  
  Notes Iwt; Fwo; Esteem 026019; Iap Approved Most recent IF: 9.466; 2011 IF: 7.286  
  Call Number UA @ lucian @ c:irua:87642 Serial 3605  
Permanent link to this record
 

 
Author Georgieva, V.; Voter, A.F.; Bogaerts, A. doi  openurl
  Title Understanding the surface diffusion processes during magnetron sputter-deposition of complex oxide Mg-Al-O thin films Type A1 Journal article
  Year 2011 Publication Crystal growth & design Abbreviated Journal Cryst Growth Des  
  Volume 11 Issue (up) 6 Pages 2553-2558  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract It is known that film structure may change dramatically with the extent of surface diffusion during the film growth process. In the present work, surface diffusion, induced thermally or activated by energetic impacts, is investigated theoretically under conditions appropriate for magnetron sputter-deposition of MgAlO thin films with varying stoichiometry. The distribution of surface diffusion energy barriers available to the system was determined for each stoichiometry, which allowed assessing in a qualitative way how much surface diffusion will take place on the time scale available between deposition events. The activation energy barriers increase with the Al concentration in the film, and therefore, the surface diffusion rates in the time frame of typical deposition rates drop, which can explain the decrease in crystallinity in the film structure and the transition to amorphous structure. The deposition process and the immediate surface diffusion enhanced by the energetic adatoms are simulated by means of a molecular dynamics model. The longer-time thermal surface diffusion and the energy landscape are studied by the temperature accelerated dynamics method, applied in an approximate way. The surface diffusion enhanced by the energetic impacts appears to be very important for the film structure in the low-temperature deposition regime.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000291074600068 Publication Date 2011-04-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1528-7483;1528-7505; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.055 Times cited 14 Open Access  
  Notes Approved Most recent IF: 4.055; 2011 IF: 4.720  
  Call Number UA @ lucian @ c:irua:89566 Serial 3806  
Permanent link to this record
 

 
Author Afanasov, I.M.; Van Tendeloo, G. doi  openurl
  Title Zirconia-modified exfoliated graphite Type A1 Journal article
  Year 2011 Publication Inorganic materials Abbreviated Journal Inorg Mater+  
  Volume 47 Issue (up) 6 Pages 603-608  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Zirconia has been incorporated into exfoliated graphite (EG) through the anodic polarization in the natural graphite-ZrO(NO3)2-HNO3-H2O system, followed by flash heating. The thermal properties of the oxidized graphites employed as precursors to EG have been studied by thermogravimetry in combination with differential scanning calorimetry, and the distribution of ZrO2 particles in the EG has been assessed by scanning and transmission electron microscopy. Conditions are described for the preparation of EG with bulk densities in the range 1.34.7 g/l and ZrO2 contents in the range 434 wt %.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000291698100008 Publication Date 2011-05-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1685;1608-3172; ISBN Additional Links UA library record; WoS full record  
  Impact Factor 0.62 Times cited Open Access  
  Notes Approved Most recent IF: 0.62; 2011 IF: 0.414  
  Call Number UA @ lucian @ c:irua:90447 Serial 3933  
Permanent link to this record
 

 
Author De Wael, K.; Verstraete, A.; van Vlierberghe, S.; Dejonghe, W.; Dubruel, P.; Adriaens, A. url  openurl
  Title The electrochemistry of a gelatin modified gold electrode Type A1 Journal article
  Year 2011 Publication International journal of electrochemical science Abbreviated Journal Int J Electrochem Sc  
  Volume 6 Issue (up) 6 Pages 1810-1819  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract This paper discusses the electrochemical behaviour of gelatin coated gold electrodes in physiological pH conditions in a potential window −1.5 till 1.0 V vs SCE by performing cyclic voltammetry. A comparison is made between gelatin A and gelatin B, which have respectively a positive and a negative net charge at physiological pH. The deposition of gelatin onto the gold surface is confirmed by means of attenuated total reflection-infrared (ATR-IR) spectroscopic analyses.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1452-3981 ISBN Additional Links UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles  
  Impact Factor 1.469 Times cited Open Access  
  Notes ; The authors would like to acknowledge the Flemish Institute for Technological Research (VITO, Belgium) and the Research Foundation-Flanders (FWO, Belgium) for the Ph.D. funding granted to Annelies Verstraete. Karolien De Wael and Sandra Van Vlierberghe are also grateful to the Research Foundation-Flanders (FWO, Belgium) for their postdoctoral fellowship. ; Approved Most recent IF: 1.469; 2011 IF: 3.729  
  Call Number UA @ admin @ c:irua:89617 Serial 5598  
Permanent link to this record
 

 
Author Razdobarin, A.G.; Mukhin, E.E.; Semenov, V.V.; Tolstyakov, S.Y.; Kochergin, M.M.; Kurskiev, G.S.; Podushnikova, K.A.; Kirilenko, D.A.; Sitnikova, A.A.; Konovalov, V.G.; Solodovchenko, S.I.; Nekhaieva, O.M.; Skorik, O.A.; Bondarenko, V.N.; Voitsenya, V.S.; pdf  doi
openurl 
  Title Diagnostic mirrors with transparent protection layer for ITER Type A1 Journal article
  Year 2011 Publication Fusion engineering and design Abbreviated Journal Fusion Eng Des  
  Volume 86 Issue (up) 6-8 Pages 1341-1344  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract Fast degradation of in-vessel optics is one of the most serious problems for all optical diagnostics in ITER. To provide the resistance to mechanical and thermal stresses along with a high stability of optical characteristics under deposition-dominated conditions we suggest using high-reflective metallic (Ag or Al) film mirrors coated on silicon substrate and protected with thin oxide film in the divertor Thomson Scattering (TS) diagnostics. The mirrors coated with Al2O3 and ZrO2 films were tested under irradiation by deuterium ions. The experimental results on the oxide films sputtering are discussed in the context of their applicability for the first mirror protection in ITER.  
  Address  
  Corporate Author Thesis  
  Publisher Elsevier science sa Place of Publication Amsterdam Editor  
  Language Wos 000297426500203 Publication Date 2011-03-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0920-3796; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.319 Times cited 6 Open Access  
  Notes Approved Most recent IF: 1.319; 2011 IF: 1.490  
  Call Number UA @ lucian @ c:irua:93631 Serial 686  
Permanent link to this record
 

 
Author Jochems, P.; Satyawali, Y.; van Roy, S.; Doyen, W.; Diels, L.; Dejonghe, W. pdf  doi
openurl 
  Title Characterization and optimization of \beta-galactosidase immobilization process on a mixed-matrix membrane Type A1 Journal article
  Year 2011 Publication Enzyme and microbial technology Abbreviated Journal  
  Volume 49 Issue (up) 6/7 Pages 580-588  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract β-Galactosidase is an important enzyme catalyzing not only the hydrolysis of lactose to the monosaccharides glucose and galactose but also the transgalactosylation reaction to produce galacto-oligosaccharides (GOS). In this study, β-galactosidase was immobilized by adsorption on a mixed-matrix membrane containing zirconium dioxide. The maximum β-galactosidase adsorbed on these membranes was 1.6 g/m2, however, maximal activity was achieved at an enzyme concentration of around 0.5 g/m2. The tests conducted to investigate the optimal immobilization parameters suggested that higher immobilization can be achieved under extreme parameters (pH and temperature) but the activity was not retained at such extreme operational parameters. The investigations on immobilized enzymes indicated that no real shift occurred in its optimal temperature after immobilization though the activity in case of immobilized enzyme was better retained at lower temperature (5 °C). A shift of 0.5 unit was observed in optimal pH after immobilization (pH 6.5 to 7). Perhaps the most striking results are the kinetic parameters of the immobilized enzyme; while the Michaelis constant (Km) value increased almost eight times compared to the free enzyme, the maximum enzyme velocity (Vmax) remained almost constant.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000298529600015 Publication Date 2011-06-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0141-0229 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:90060 Serial 7608  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: