toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Cantoro, M.; Klekachev, A.V.; Nourbakhsh, A.; Sorée, B.; Heyns, M.M.; de Gendt, S. doi  openurl
  Title Long-wavelength, confined optical phonons in InAs nanowires probed by Raman spectroscopy Type A1 Journal article
  Year 2011 Publication (up) European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume 79 Issue 4 Pages 423-428  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Strongly confined nano-systems, such as one-dimensional nanowires, feature deviations in their structural, electronic and optical properties from the corresponding bulk. In this work, we investigate the behavior of long-wavelength, optical phonons in vertical arrays of InAs nanowires by Raman spectroscopy. We attribute the main changes in the spectral features to thermal anharmonicity, due to temperature effects, and rule out the contribution of quantum confinement and Fano resonances. We also observe the appearance of surface optical modes, whose details allow for a quantitative, independent estimation of the nanowire diameter. The results shed light onto the mechanisms of lineshape change in low-dimensional InAs nanostructures, and are useful to help tailoring their electronic and vibrational properties for novel functionalities.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000288120600005 Publication Date 2011-02-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028;1434-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited 10 Open Access  
  Notes ; ; Approved Most recent IF: 1.461; 2011 IF: 1.534  
  Call Number UA @ lucian @ c:irua:89502 Serial 1841  
Permanent link to this record
 

 
Author Yang, W.; Nelissen, K.; Kong, M.H.; Li, Y.T.; Tian, Y.M. pdf  doi
openurl 
  Title Melting properties of two-dimensional multi-species colloidal systems in a parabolic trap Type A1 Journal article
  Year 2011 Publication (up) European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume 83 Issue 4 Pages 499-505  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The angular and radial melting properties of two-dimensional classical systems consisting of different types of particles confined in a parabolic trap are studied through modified Monte Carlo simulations. A universal behavior of the angular melting process is found, which occurs in multiple steps due to shell depended melting temperatures. The melting sequence of the different shells is determined by two major factors: (1) the confinement strength which each shell is subjected to, and (2) the specific structure of each shell. Further, a continuous radial disordering of the particle types forming a single circular shell is found and analyzed. This phenomenon has never been observed before in two-dimensional mono-dispersive systems. This continuous radial disordering results from the high energy barrier between different particle types in multi-species systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000296633700013 Publication Date 2011-10-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028;1434-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited 2 Open Access  
  Notes ; This work was supported by the National Natural Science Foundation of China under Grant No. 11047111, the Major State Basic Research Development Program of China (973) under Grant No. 2009CB724201, the Key Science and Technology Program of Shanxi Province of China under Grant No. 20090321085, the Doctors' Initial Foundation of Taiyuan University of Science and Technology under Grant No. 20092010, the Youth Foundation of Taiyuan University of Science and Technology under Grant No. 20113020, the FWO-Vl (Belgium) and CNPq (Brazil). Part of the calculations were carried out using the CalcUA core facility of Universiteit Antwerpen (Belgium), a division of Flemish Supercomputer Center VSC, and in the Center for Computational Science of CASHIPS (China). ; Approved Most recent IF: 1.461; 2011 IF: 1.534  
  Call Number UA @ lucian @ c:irua:93589 Serial 1989  
Permanent link to this record
 

 
Author Verberck, B.; Tarakina, N.V. pdf  doi
openurl 
  Title Tubular fullerenes inside carbon nanotubes : optimal molecular orientation versus tube radius Type A1 Journal article
  Year 2011 Publication (up) European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume 80 Issue 3 Pages 355-362  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract We present an investigation of the orientations and positions of tubular fullerene molecules (C90, ..., C200) encapsulated in single-walled carbon nanotubes (SWCNT), a series of so-called fullerene nanopeapods. We find that increasing the tube radius leads to the following succession of energetically stable regimes: (1) lying molecules positioned on the tube's long axis; (2) tilted molecules on the tube's long axis; and (3) lying molecules shifted away from the tube's long axis. As opposed to C70 and C80 molecules encapsulated in a SWCNT, standing orientations do not develop. Our results are relevant for the possible application of molecular-orientation-dependent electronic properties of fullerene nanopeapods, and also for the interpretation of future experiments on double-walled carbon nanotube formation by annealing fullerene peapod systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000289576200010 Publication Date 2011-03-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028;1434-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited 10 Open Access  
  Notes ; This work was financially supported by the Research Foundation – Flanders (FWO-VI). B.V. is a Postdoctoral Fellow of the Research Foundation – Flanders (FWO-VI). ; Approved Most recent IF: 1.461; 2011 IF: 1.534  
  Call Number UA @ lucian @ c:irua:89286 Serial 3738  
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 (up) Fusion engineering and design Abbreviated Journal Fusion Eng Des  
  Volume 86 Issue 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 Caratelli, D.; Gielis, J.; Natalini, P.; Ricci, P.E.; Tavkhelidze, I. pdf  doi
openurl 
  Title The Robin problem for the Helmholtz equation in a starlike planar domain Type A1 Journal article
  Year 2011 Publication (up) Georgian mathematical journal Abbreviated Journal  
  Volume 18 Issue 3 Pages 465-479  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract The interior and exterior Robin problems for the Helmholtz equation in starlike planar domains are addressed by using a suitable Fourier-like technique. Attention is in particular focused on normal-polar domains whose boundaries are defined by the so-called superformula introduced by J. Gielis. A dedicated numerical procedure based on the computer algebra system Mathematica© is developed in order to validate the proposed approach. In this way, highly accurate approximations of the solution, featuring properties similar to the classical ones, are obtained. The computed results are found to be in good agreement with the theoretical findings on Fourier series expansion presented by L. Carleson.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000296166100004 Publication Date 2021-02-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1072-947x 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:91086 Serial 8658  
Permanent link to this record
 

 
Author Jochems, P.; Satyawali, Y.; Diels, L.; Dejonghe, W. doi  openurl
  Title Enzyme immobilization on/in polymeric membranes : status, challenges and perspectives in biocatalytic membrane reactors (BMRs) Type A1 Journal article
  Year 2011 Publication (up) Green chemistry : cutting-edge research for a greener sustainable future Abbreviated Journal  
  Volume 13 Issue 7 Pages 1609-1623  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Immobilization of enzymes is beneficial in terms of improving the process economics by enabling enzyme re-use and enhancing overall productivity and robustness. Increasingly, membranes are thought to be good supports for enzyme immobilization. These resulting biocatalytic membranes are integrated in reactors known as biocatalytic membrane reactors (BMRs) which enable the integration of biocatalysis and separation. Often the available commercial membranes require modifications to make them suitable for enzyme immobilization. Different immobilization techniques can be used on such suitable membranes, but no general rules exist for making a choice between them. Despite the advantages of BMR application, there are some issues which need to be addressed in order to achieve up-scaling of such systems. In this review, the different aspects of enzyme immobilization on membranes are discussed to show the complexity of this interdisciplinary technology. In addition, the existing issues which require further investigation are highlighted.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000292450600002 Publication Date 2011-05-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9262; 1463-9270 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:89567 Serial 7930  
Permanent link to this record
 

 
Author Abreu, Y.; Cruz, C.M.; van Espen, P.; Piñera, I.; Leyva, A.; Cabal, A.E. openurl 
  Title Multiscale modeling of radiation damage and annealing in Si samples implanted with 57-Mn radioactive ions Type P1 Proceeding
  Year 2011 Publication (up) IEEE conference record T2 – IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th, International Workshop on Room-Temperature Semiconductor X-Ray and, Gamma-Ray Detectors, OCT 23-29, 2011, Valencia, SPAIN Abbreviated Journal  
  Volume Issue Pages 1754-1756  
  Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The radiation damage created in silicon materials by Mn-57 -> Fe-57 ion implantation has been studied and characterized by Mossbauer spectroscopy showing four main lines, assigned to: substitutional, interstitial and damaged configuration sites of the implanted ions. Nevertheless, the Mossbauer spectrum of Fe-57 in this materials remains with some ambiguous identification regarding the implantation configurations before and after annealing, specially the damaged configurations and its evolution. In the present work some possible implantation configurations are suggested and evaluated using a multiscale approach by Monte Carlo ion transport and electronic structure calculations within DFT. The proposed implantation environments were evaluated in terms of stability and the Fe-57 hyperfine parameters were calculated to establish the connections with the experimental observations. Good agreement was found between the experimental and the calculated hyperfine parameters for some configurations; suggesting which ones could be the implantation environments before and after sample annealing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304755601202 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 978-1-4673-0120-6 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:113073 Serial 8289  
Permanent link to this record
 

 
Author Piñera, I.; Abreu, Y.; van Espen, P.; Diaz, A.; Leyva, A.; Cruz, C.M. openurl 
  Title Radiation damage evaluation on LYSO and LuYAP materials through Dpa calculation assisted by Monte Carlo method Type P1 Proceeding
  Year 2011 Publication (up) IEEE conference record T2 – IEEE Nuclear Science Symposium/Medical Imaging Conference (NSS/MIC)/18th, International Workshop on Room-Temperature Semiconductor X-Ray and, Gamma-Ray Detectors, OCT 23-29, 2011, Valencia, SPAIN Abbreviated Journal  
  Volume Issue Pages 1609-1611  
  Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The aim of the present work is to study the radiation damage induced in LYSO and LuYAP crystals by the gamma radiation and the secondary electrons/positrons generated. The displacements per atom (dpa) distributions inside each material were calculated following the Monte Carlo assisted Classical Method (MCCM) introduced by the authors. As gamma sources were used Sc-44, Na-22 and V-48. Also the energy of gammas from the annihilation processes (511 keV) was included in the study. This procedure allowed studying the in-depth dpa distributions inside each crystal for all four sources. It was also possible to obtain the separate contribution from each atom to the total dpa. The LYSO crystals were found to receive more damage, mainly provoked by the displacements of silicon and oxygen atoms.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000304755601169 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 978-1-4673-0120-6 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:113072 Serial 8447  
Permanent link to this record
 

 
Author Katti, G.; Stucchi, M.; Velenis, D.; Sorée, B.; de Meyer, K.; Dehaene, W. doi  openurl
  Title Temperature-dependent modeling and characterization of through-silicon via capacitance Type A1 Journal article
  Year 2011 Publication (up) IEEE electron device letters Abbreviated Journal Ieee Electr Device L  
  Volume 32 Issue 4 Pages 563-565  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A semianalytical model of the through-silicon via (TSV) capacitance for elevated operating temperatures is derived and verified with electrical measurements. The effect of temperature on the increase in TSV capacitance over different technology parameters is explored, and it is shown that higher oxide thickness reduces the impact of temperature rise on TSV capacitance, while with low doped substrates, which are instrumental for reducing the TSV capacitance, the sensitivity of TSV capacitance to temperature is large and cannot be ignored.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000288664800045 Publication Date 2011-03-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0741-3106;1558-0563; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.048 Times cited 27 Open Access  
  Notes ; ; Approved Most recent IF: 3.048; 2011 IF: 2.849  
  Call Number UA @ lucian @ c:irua:89402 Serial 3498  
Permanent link to this record
 

 
Author King, G.; Abakumov, A.M.; Woodward, P.M.; Llobet, A.; Tsirlin, A.A.; Batuk, D.; Antipov, E.V. doi  openurl
  Title The high-temperature polymorphs of K3AlF6 Type A1 Journal article
  Year 2011 Publication (up) Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 50 Issue 16 Pages 7792-7801  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The crystal structures of the three high-temperature polymorphs of K3AlF6 have been solved from neutron powder diffraction, synchrotron X-ray powder diffraction, and electron diffraction data. The β-phase (stable between 132 and 153 °C) and γ-phase (stable between 153 to 306 °C) can be described as unusually complex superstructures of the double-perovskite structure (K2KAlF6) which result from noncooperative tilting of the AlF6 octahedra. The β-phase is tetragonal, space group I4/m, with lattice parameters of a = 13.3862(5) Å and c = 8.5617(3) Å (at 143 °C) and Z = 10. In this phase, one-fifth of the AlF6 octahedra are rotated about the c-axis by 45° while the other four-fifths remain untilted. The large 45° rotations result in edge sharing between these AlF6 octahedra and the neighboring K-centered polyhedra, resulting in pentagonal bipyramidal coordination for four-fifths of the K+ ions that reside on the B-sites of the perovskite structure. The remaining one-fifth of the K+ ions on the B-sites retain octahedral coordination. The γ-phase is orthorhombic, space group Fddd, with lattice parameters of a = 36.1276(4) Å, b = 17.1133(2) Å, and c = 12.0562(1) Å (at 225 °C) and Z = 48. In the γ-phase, one-sixth of the AlF6 octahedra are randomly rotated about one of two directions by 45° while the other five-sixths remain essentially untilted. These rotations result in two-thirds of the K+ ions on the B-site obtaining 7-fold coordination while the other one-third remain in octahedral coordination. The δ-phase adopts the ideal cubic double-perovskite structure, space group Fmm, with a = 8.5943(1) Å at 400 °C. However, pair distribution function analysis shows that locally the δ-phase is quite different from its long-range average crystal structure. The AlF6 octahedra undergo large-amplitude rotations which are accompanied by off-center displacements of the K+ ions that occupy the 12-coordinate A-sites.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Easton, Pa Editor  
  Language Wos 000293493100052 Publication Date 2011-07-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.857 Times cited 19 Open Access  
  Notes Approved Most recent IF: 4.857; 2011 IF: 4.601  
  Call Number UA @ lucian @ c:irua:91131 Serial 1468  
Permanent link to this record
 

 
Author Batuk, D.; Hadermann, J.; Abakumov, A.; Vranken, T.; Hardy, A.; van Bael, M.; Van Tendeloo, G. doi  openurl
  Title Layered perovskite-like Pb2Fe2O5 structure as a parent matrix for the nucleation and growth of crystallographic shear planes Type A1 Journal article
  Year 2011 Publication (up) Inorganic chemistry Abbreviated Journal Inorg Chem  
  Volume 50 Issue 11 Pages 4978-4986  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The Pb2Fe2O5 compound with a layered intergrowth structure has been prepared by a solid-state reaction at 700 °C. The incommensurate compound crystallizes in a tetragonal system with a = 3.9037(2) Å, c = 3.9996(4) Å, and q = 0.1186(4)c*, or when treated as a commensurate approximant, a = 3.9047(2) Å, c = 36.000(3) Å, space group I4/mmm. The crystal structure of Pb2Fe2O5 was resolved from transmission electron microscopy data. Atomic coordinates and occupancies of the cation positions were estimated from high-angle annular dark-field scanning transmission electron microscopy data. Direct visualization of the positions of the oxygen atoms was possible using annular bright-field scanning transmission electron microscopy. The structure can be represented as an intergrowth of perovskite blocks and partially disordered blocks with a structure similar to that of the Bi2O2 blocks in Aurivillius-type phases. The A-cation positions at the border of the perovskite block and the cation positions in the Aurivillius-type blocks are jointly occupied by Pb2+ and Fe3+ cations, resulting in a layer sequence along the c axis: PbOFeO2PbOFeO2Pb7/8Fe1/8O1xFe5/8Pb3/8O2Fe5/8Pb3/8. Upon heating, the layered Pb2Fe2O5 structure transforms into an anion-deficient perovskite modulated by periodically spaced crystallographic shear (CS) planes. Considering the layered Pb2Fe2O5 structure as a parent matrix for the nucleation and growth of CS planes allows an explanation of the specific microstructure observed for the CS structures in the PbFeO system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Easton, Pa Editor  
  Language Wos 000290978400038 Publication Date 2011-04-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.857 Times cited 16 Open Access  
  Notes Approved Most recent IF: 4.857; 2011 IF: 4.601  
  Call Number UA @ lucian @ c:irua:90141 Serial 1809  
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 (up) Inorganic materials Abbreviated Journal Inorg Mater+  
  Volume 47 Issue 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 Backer, L.; Vos, W.; Dieriks, B.; Daems, D.; Verhulst, S.; Vinchurkar, S.; Ides, K.; de Backer, J.; Germonpré, P.; de Backer, W. url  doi
openurl 
  Title The effects of long-term noninvasive ventilation in hypercapnic COPD patients : a randomized controlled pilot study Type A1 Journal article
  Year 2011 Publication (up) International journal of chronic obstructive pulmonary disease Abbreviated Journal Int J Chronic Obstr  
  Volume 6 Issue Pages 615-624  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract Introduction: Noninvasive ventilation (NIV) is a well-established treatment for acute-on-chronic respiratory failure in hypercapnic COPD patients. Less is known about the effects of a long-term treatment with NIV in hypercapnic COPD patients and about the factors that may predict response in terms of improved oxygenation and lowered CO2 retention.Methods: In this study, we randomized 15 patients to a routine pharmacological treatment (n = 5, age 66 [standard deviation ± 6] years, FEV1 30.5 [±5.1] %pred, PaO2 65 [±6] mmHg, PaCO2 52.4 [±6.0] mmHg) or to a routine treatment and NIV (using the Synchrony BiPAP device [Respironics, Inc, Murrsville, PA]) (n = 10, age 65 [±7] years, FEV1 29.5 [±9.0] %pred, PaO2 59 [±13] mmHg, PaCO2 55.4 [±7.7] mmHg) for 6 months. We looked at arterial blood gasses, lung function parameters and performed a low-dose computed tomography of the thorax, which was later used for segmentation (providing lobe and airway volumes, iVlobe and iVaw) and post-processing with computer methods (providing airway resistance, iRaw) giving overall a functional image of the separate airways and lobes.Results: In both groups there was a nonsignificant change in FEV1 (NIV group 29.5 [9.0] to 38.5 [14.6] %pred, control group 30.5 [5.1] to 36.8 [8.7] mmHg). PaCO2 dropped significantly only in the NIV group (NIV: 55.4 [7.7] → 44.5 [4.70], P = 0.0076; control: 52.4 [6.0] → 47.6 [8.2], NS). Patients actively treated with NIV developed a more inhomogeneous redistribution of mass flow than control patients. Subsequent analysis indicated that in NIV-treated patients that improve their blood gases, mass flow was also redistributed towards areas with higher vessel density and less emphysema, indicating that flow was redistributed towards areas with better perfusion. There was a highly significant correlation between the % increase in mass flow towards lobes with a blood vessel density of >9% and the increase in PaO2. Improved ventilation–perfusion match and recruitment of previously occluded small airways can explain the improvement in blood gases.Conclusion: We can conclude that in hypercapnic COPD patients treated with long-term NIV over 6 months, a mass flow redistribution occurs, providing a better ventilation–perfusion match and hence better blood gases and lung function. Control patients improve homogeneously in iVaw and iRaw, without improvement in gas exchange since there is no improved ventilation/perfusion ratio or increased alveolar ventilation. These differences in response can be detected through functional imaging, which gives a more detailed report on regional lung volumes and resistances than classical lung function tests do. Possibly only patients with localized small airway disease are good candidates for long-term NIV treatment. To confirm this and to see if better arterial blood gases also lead to better health related quality of life and longer survival, we have to study a larger population.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000208709800066 Publication Date 2011-11-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1178-2005; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.157 Times cited 28 Open Access  
  Notes ; ; Approved Most recent IF: 3.157; 2011 IF: NA  
  Call Number UA @ lucian @ c:irua:93164 Serial 866  
Permanent link to this record
 

 
Author De Backer, L.A.; Vos, W.G.; Salgado, R.; de Backer, J.W.; Devolder, A.; Verhulst, S.L.; Claes, R.; Germonpré, P.R.; de Backer, W.A. url  doi
openurl 
  Title Functional imaging using computer methods to compare the effect of salbutamol and ipratropium bromide in patient-specific airway models of COPD Type A1 Journal article
  Year 2011 Publication (up) International journal of chronic obstructive pulmonary disease Abbreviated Journal Int J Chronic Obstr  
  Volume 6 Issue Pages 637-646  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract Background: Salbutamol and ipratropium bromide improve lung function in patients with chronic obstructive pulmonary disease (COPD). However, their bronchodilating effect has not yet been compared in the central and distal airways. Functional imaging using computational fluid dynamics offers the possibility of making such a comparison. The objective of this study was to assess the effects of salbutamol and ipratropium bromide on the geometry and computational fluid dynamics-based resistance of the central and distal airways.Methods: Five patients with Global Initiative for Chronic Obstructive Lung Disease Stage III COPD were randomized to a single dose of salbutamol or ipratropium bromide in a crossover manner with a 1-week interval between treatments. Patients underwent lung function testing and a multislice computed tomography scan of the thorax that was used for functional imaging. Two hours after dosing, the patients again underwent lung function tests and repeat computed tomography.Results: Lung function parameters, including forced expiratory volume in 1 second, vital capacity, overall airway resistance, and specific airway resistance, changed significantly after administration of each product. On functional imaging, the bronchodilating effect was greater in the distal airways, with a corresponding drop in airway resistance, compared with the central airways. Salbutamol and ipratropium bromide were equally effective at first glance when looking at lung function tests, but when viewed in more detail with functional imaging, hyporesponsiveness could be shown for salbutamol in one patient. Salbutamol was more effective in the other patients.Conclusion: This pilot study gives an innovative insight into the modes of action of salbutamol and ipratropium bromide in patients with COPD, using the new techniques of functional imaging and computational fluid dynamics.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000208709800068 Publication Date 2011-11-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1178-2005; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.157 Times cited 25 Open Access  
  Notes ; ; Approved Most recent IF: 3.157; 2011 IF: NA  
  Call Number UA @ lucian @ c:irua:93165 Serial 1300  
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 (up) International journal of electrochemical science Abbreviated Journal Int J Electrochem Sc  
  Volume 6 Issue 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 Simon, Q.; Barreca, D.; Bekermann, D.; Gasparotto, A.; Maccato, C.; Comini, E.; Gombac, V.; Fornasiero, P.; Lebedev, O.I.; Turner, S.; Devi, A.; Fischer, R.A.; Van Tendeloo, G. pdf  doi
openurl 
  Title Plasma-assisted synthesis of Ag/ZnO nanocomposites : first example of photo-induced H2 production and sensing Type A1 Journal article
  Year 2011 Publication (up) International journal of hydrogen energy Abbreviated Journal Int J Hydrogen Energ  
  Volume 36 Issue 24 Pages 15527-15537  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Ag/ZnO nanocomposites were developed by a plasma-assisted approach. The adopted strategy exploits the advantages of Plasma Enhanced-Chemical Vapor Deposition (PE-CVD) for the growth of columnar ZnO arrays on Si(100) and Al2O3 substrates, in synergy with the infiltration power of the Radio Frequency (RF)-sputtering technique for the subsequent dispersion of different amounts of Ag nanoparticles (NPs). The resulting composites, both as-prepared and after annealing in air, were thoroughly characterized with particular attention on their morphological organization, structure and composition. For the first time, the above systems have been used as catalysts in the production of hydrogen by photo-reforming of alcoholic solutions, yielding a stable H2 evolution even by the sole use of simulated solar radiation. In addition, Ag/ZnO nanocomposites presented an excellent response in the gas-phase detection of H2, opening attractive perspectives for advanced technological applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000297089700006 Publication Date 2011-10-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0360-3199; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.582 Times cited 62 Open Access  
  Notes Esteem 026019; Fwo Approved Most recent IF: 3.582; 2011 IF: 4.054  
  Call Number UA @ lucian @ c:irua:91901 Serial 2627  
Permanent link to this record
 

 
Author Verberck, B. url  doi
openurl 
  Title Symmetry-adapted rotator functions for molecules in cylindrical confinement Type A1 Journal article
  Year 2011 Publication (up) International journal of molecular sciences Abbreviated Journal Int J Mol Sci  
  Volume 12 Issue 1 Pages 317-333  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We present a general description of the formalism of symmetry-adapted rotator functions (SARFs) for molecules in cylindrical confinement. Molecules are considered as clusters of interaction centers (ICs), can have any symmetry, and can display different types of ICs. Cylindrical confinement can be realized by encapsulation in a carbon nanotube (CNT). The potential energy of a molecule surrounded by a CNT can be calculated by evaluating a limited number of terms of an expansion into SARFs, which offers a significant reduction of the computation time. Optimal molecular orientations can be deduced from the resulting potential energy landscape. Examples, including the case of a molecule with cubic symmetry inside a CNT, are discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000286583400017 Publication Date 2011-01-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1422-0067; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.226 Times cited 1 Open Access  
  Notes ; ; Approved Most recent IF: 3.226; 2011 IF: NA  
  Call Number UA @ lucian @ c:irua:88048 Serial 3402  
Permanent link to this record
 

 
Author Delville, R.; Malard, B.; Pilch, J.; Sittner, P.; Schryvers, D. pdf  doi
openurl 
  Title Transmission electron microscopy investigation of dislocation slip during superelastic cycling of NiTi wires Type A1 Journal article
  Year 2011 Publication (up) International journal of plasticity Abbreviated Journal Int J Plasticity  
  Volume 27 Issue 2 Pages 282-297  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Superelastic deformation of thin NiTi wires containing various nanograined microstructures was investigated by tensile cyclic loading with in situ evaluation of electric resistivity. Defects created by the superelastic cycling in these wires were analyzed by transmission electron microscopy. The role of dislocation slip in superelastic deformation is discussed. NiTi wires having finest microstructures (grain diameter <100 nm) are highly resistant against dislocation slip, while those with fully recrystallized microstructure and grain size exceeding 200 nm are prone to dislocation slip. The density of the observed dislocation defects increases significantly with increasing grain size. The upper plateau stress of the superelastic stressstrain curves is largely grain size independent from 10 up to 1000 nm. It is hence claimed that the HallPetch relationship fails for the stress-induced martensitic transformation in this grain size range. It is proposed that dislocation slip taking place during superelastic cycling is responsible for the accumulated irreversible strains, cyclic instability and degradation of functional properties. No residual martensite phase was found in the microstructures of superelastically cycled wires by TEM and results of the in situ electric resistance measurements during straining also indirectly suggest that none or very little martensite phase remains in the studied cycled superelastic wires after unloading. The accumulation of dislocation defects, however, does not prevent the superelasticity. It only affects the shape of the stressstrain response, makes it unstable upon cycling and changes the deformation mode from localized to homogeneous. The activity of dislocation slip during superelastic deformation of NiTi increases with increasing test temperature and ultimately destroys the superelasticity as the plateau stress approaches the yield stress for slip. Deformation twins in the austenite phase ({1 1 4} compound twins) were frequently found in cycled wires having largest grain size. It is proposed that they formed in the highly deformed B19′ martensite phase during forward loading and are retained in austenite after unloading. Such twinning would represent an additional deformation mechanism of NiTi yielding residual irrecoverable strains.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000284921800007 Publication Date 2010-05-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0749-6419; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 5.702 Times cited 157 Open Access  
  Notes Fwo; Iap Approved Most recent IF: 5.702; 2011 IF: 4.603  
  Call Number UA @ lucian @ c:irua:84651 Serial 3709  
Permanent link to this record
 

 
Author Simon, P.; Bogaerts, A. doi  openurl
  Title Vibrational level population of nitrogen impurities in low-pressure argon glow discharges Type A1 Journal article
  Year 2011 Publication (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 4 Pages 804-810  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The vibrational level populations of the electronic ground state of the nitrogen molecule have been calculated for typical glow discharge conditions in argonnitrogen mixtures with nitrogen concentrations between 0.1 and 1%. Stationary solutions of the master equations of the vibrational levels have been obtained using numerical methods. The main mechanisms responsible for the population and depopulation of the vibrational levels, and for the overall shape of the vibrational distribution function are pointed out. It has been found that vibrationvibration collisions play only a minor role and therefore the population of the vibrational levels is basically determined by the electron temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000288703300012 Publication Date 2010-12-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0267-9477;1364-5544; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.379 Times cited 6 Open Access  
  Notes Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ lucian @ c:irua:87530 Serial 3842  
Permanent link to this record
 

 
Author Rouchon, V.; Pellizzi, E.; Duranton, M.; Vanmeert, F.; Janssens, K. doi  openurl
  Title Combining XANES, ICP-AES, and SEM/EDS for the study of phytate chelating treatments used on iron gall ink damaged manuscripts Type A1 Journal article
  Year 2011 Publication (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 12 Pages 2434-2441  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Many historical documents written with iron gall inks are endangered by the corrosive effects of these inks. In this work, a combination of complementary analytical methods was used for the first time in order to study the phytate process which is used in conservation studios to stabilize damaged manuscripts. This process consists of an antioxidant treatment performed by means of a calcium phytate (CP) solution, followed by a deacidification treatment performed with a calcium carbonate (CC) solution. The antioxidant treatment capitalizes on the properties of myo-inositol hexaphosphoric acid (phytic acid) that inhibits iron through chelation. In order to use relatively low acidic solutions, the pH of the CP solution is increased up to values between 5 and 6, which is in the range of the CP precipitation threshold. This study was performed on laboratory samples made of paper impregnated with iron gall ink and artificially aged in climatic chambers. It aims to investigate how the CP precipitate impacts the efficiency of the treatment. Side effects, such as elemental losses and deposits, were measured by means of several analytical techniques (FeK Edge XANES, SEM/EDS, and ICP-AES). These measurements were crosschecked with a ready to use colour spot test made of bathophenanthroline impregnated paper. It appeared that the CP treatment should necessarily be followed by the deacidification treatment in order to achieve long term stability. The precipitation of CP in the treating solution does finally not impact the efficiency of the treatment despite the fact that it should theoretically lower the availability of phytate to chelate iron. A scenario is proposed to explain this point.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000297030400008 Publication Date 2011-10-06  
  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 10 Open Access  
  Notes ; This research was funded by SOLEIL (proposals 20060396 and 20080761) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. We are thankful to the paper conservator students of the Institut National du Patrimoine who were involved in some of the sample preparations, and to Dr Dominique Thiaudiere and Dr Solenn Reguer for their assistance and help during the experiments performed at SOLEIL beamline “DIFFABS”. ; Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ admin @ c:irua:93845 Serial 5527  
Permanent link to this record
 

 
Author Cagno, S.; Nuyts, G.; Bugani, S.; De Vis, K.; Schalm, O.; Caen, J.; Helfen, L.; Cotte, M.; Reischig, P.; Janssens, K. doi  openurl
  Title Evaluation of manganese-bodies removal in historical stained glass windows via SR-\mu-XANES/XRF and SR-\mu-CT Type A1 Journal article
  Year 2011 Publication (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 12 Pages 2442-2451  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The speed and effectiveness of a conservation treatment used for stained glass windows have been investigated. Dark-coloured Mn-rich stains can be found in the alteration layer of ancient glass artefacts and cause the surface to turn brown/black: this phenomenon is known as Mn-browning or Mn-staining. While in glass manganese is present in the +II or +III oxidation states, in the Mn-rich bodies, manganese is in a higher oxidation state (+IV). In restoration practice, mildly reducing solutions are employed to eliminate the dark colour and restore the clear appearance of the glass. In this paper the effectiveness and side effects of the use of hydroxylamine hydrochloride for this purpose are assessed. Archaeological fragments of stained glass windows, dated to the 14th century and originating from Sidney Sussex College, Cambridge (UK), were examined by means of synchrotron radiation (SR) based microscopic X-ray Absorption Near-Edge Spectroscopy (μ-XANES) and microscopic X-Ray Fluorescence (μ-XRF) and with high resolution computed absorption tomography (μ-CT) before, during and after the treatment. The monitoring of the glass fragments during the treatment allows us to better understand the manner in which the process unfolds and its kinetics. The results obtained reveal that the hydroxylamine hydrochloride treatment is effective, but also that it has a number of unwanted side effects. These findings are useful for optimizing the time and other modalities of the Mn-reducing treatment as well as minimizing its unwanted results.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000297030400009 Publication Date 2011-10-11  
  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 3.379 Times cited 17 Open Access  
  Notes ; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. Special thanks to Ms Leonie Seliger, head of the stained-glass conservation studio (The Cathedral Studios-The Chapter of Canterbury Cathedral) for the supply of the archaeological samples. The authors gratefully acknowledge ESRF for granting beamtime (proposal EC-602). ; Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ admin @ c:irua:93848 Serial 5613  
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 (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 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 van der Snickt, G.; Miliani, C.; Janssens, K.; Brunetti, B.G.; Romani, A.; Rosi, F.; Walter, P.; Castaing, J.; de Nolf, W.; Klaassen, L.; Labarque, I.; Wittermann, R. doi  openurl
  Title Material analyses of “Christ with singing and music-making Angels”, a late 15th-C panel painting attributed to Hans Memling and assistants : part 1 : non-invasive in situ investigations Type A1 Journal article
  Year 2011 Publication (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 11 Pages 2216-2229  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract In cultural heritage science, compositional data is traditionally obtained from works of art through the analysis of samples by means of various bench-top instruments (scanning electron microscope, Raman spectrometer, etc.). Alternatively, the object can be transported to a laboratory where it may be examined, usually by spectroscopic methods working in reflection mode. However, this paper describes how a complementary set of mobile and portable instruments was deployed in situ to gain a comprehensive view on the materials and related ageing compounds of an (almost) unmovable 15th-C polyptych, prior to and in preparation of the extraction of a limited number of samples. In line with the methodological approach discussed, PXRF was first employed as an efficient screening tool. The ensuing elemental data was supplemented by more specific information on both organic as inorganic materials supplied by reflection near- and mid-FTIR spectroscopy and fluorimetry. In completion, a limited number of diffraction patterns were collected with a mobile XRD instrument in order to identify the constituent crystalline phases in pigments, grounding materials and degradation products. In this way, it could be demonstrated how a rich array of colours was obtained by means of a limited palette of pigments: lead white, lead tin yellow, azurite, natural ultramarine, bone black, vermillion, madder lake, and a green copper-organo complex were detected and situated on the panels. Remarkably, next to chalk also gypsum was found in the ground layer(s) of this Western European easel painting. The relatively large surface of the background was covered with gold leaf; the analyses seem to point towards the labour-intensive water gilding technique. The versatility of this combination of analytical techniques was further illustrated by the accurate characterisation of degradation products affecting the readability and conservation of the painting: the overall presence of a calcium oxalate-based film of variable thickness was established. Nevertheless, further analysis of cross-sectioned samples was considered desirable in order to study the stratigraphy, to gain direct access to altered and sub-imposed layers and to allow highly detailed analysis of micrometric degradation products by state-of-the art techniques (i.e. synchrotron radiation).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000296021800010 Publication Date 2011-09-23  
  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 32 Open Access  
  Notes ; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). 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. The staff of the Royal Museum of Fine Arts Antwerp is acknowledged for this pleasant cooperation and the authorisation for the publication of the images in this article. Therefore, a word of gratitude to Paul Huvenne, Yolande Deckers, Stef Antonissen and Gwen Borms. In addition, the authors would like to thank the MOLAB's team operators Chiari Anselmi and Federica Presciutti. MOLAB analyses have been carried out through the support of the EU within the 6th Framework Programme (Contract Eu-ARTECH, RII3-CT-2004-506171). ; Approved Most recent IF: 3.379; 2011 IF: 3.220  
  Call Number UA @ admin @ c:irua:93680 Serial 5705  
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 (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 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 Janssens, K. doi  openurl
  Title Synchrotron radiation in art and archaeology Type Editorial
  Year 2011 Publication (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 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 (up) Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom  
  Volume 26 Issue 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 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 (up) Journal of analytical atomic spectrometry Abbreviated Journal  
  Volume 26 Issue 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 Hezareh, T.; Razavi, F.S.; Kremer, R.K.; Habermeier, H.-U.; Lebedev, O.I.; Kirilenko, D.; Van Tendeloo, G. pdf  doi
openurl 
  Title Effect of PbZr0.52Ti0.48O3 thin layer on structure, electronic and magnetic properties of La0.65Sr0.35MnO3 and La0.65Ca0.30MnO3 thin-films Type A1 Journal article
  Year 2011 Publication (up) Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 109 Issue 11 Pages 113707,1-113707,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Epitaxial thin film heterostructures of high dielectric PbZr<sub>1-x</sub>Ti<sub>x</sub>O<sub>3</sub> (PZT) and La<sub>1-x</sub>A<sub>x</sub>MnO<sub>3</sub> (A-divalent alkaline earth metals such as Sr (LSMO) and Ca (LCMO)) were grown on SrTiO<sub>3</sub> substrates and their structure, temperature dependence of electrical resistivity, and magnetization were investigated as a function of the thickness of the LSMO(LCMO) layer. The microstructures of the samples were analyzed by TEM. By applying an electric field across the PZT layer, we applied a ferrodistortive pressure on the manganite layer and studied the correlations between lattice distortion and electric transport and magnetic properties of the CMR materials.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000292214700069 Publication Date 2011-06-06  
  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 4 Open Access  
  Notes Approved Most recent IF: 2.068; 2011 IF: 2.168  
  Call Number UA @ lucian @ c:irua:90964 Serial 843  
Permanent link to this record
 

 
Author Vandenberghe, W.; Sorée, B.; Magnus, W.; Fischetti, M.V. doi  openurl
  Title Generalized phonon-assisted Zener tunneling in indirect semiconductors with non-uniform electric fields : a rigorous approach Type A1 Journal article
  Year 2011 Publication (up) Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 109 Issue 12 Pages 124503-124503,12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A general framework to calculate the Zener current in an indirect semiconductor with an externally applied potential is provided. Assuming a parabolic valence and conduction band dispersion, the semiconductor is in equilibrium in the presence of the external field as long as the electron-phonon interaction is absent. The linear response to the electron-phonon interaction results in a non-equilibrium system. The Zener tunneling current is calculated from the number of electrons making the transition from valence to conduction band per unit time. A convenient expression based on the single particle spectral functions is provided, enabling the evaluation of the Zener tunneling current under any three-dimensional potential profile. For a one-dimensional potential profile an analytical expression is obtained for the current in a bulk semiconductor, a semiconductor under uniform field, and a semiconductor under a non-uniform field using the WKB (Wentzel-Kramers-Brillouin) approximation. The obtained results agree with the Kane result in the low field limit. A numerical example for abrupt p-n diodes with different doping concentrations is given, from which it can be seen that the uniform field model is a better approximation than the WKB model, but a direct numerical treatment is required for low bias conditions.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000292331200134 Publication Date 2011-06-21  
  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 41 Open Access  
  Notes ; William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ; Approved Most recent IF: 2.068; 2011 IF: 2.168  
  Call Number UA @ lucian @ c:irua:90808 Serial 1325  
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 (up) Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 110 Issue 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
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: