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Author Wang, W.; Van Duppen, B.; Peeters, F.M.
Title Intense-terahertz-laser-modulated magnetopolaron effect on shallow-donor states in the presence of magnetic field in the Voigt configuration Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue (down) 1 Pages 014114
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The laser-modulated magnetopolaron effect on shallow donors in semiconductors is investigated in the presence of a magnetic field in the Voigt configuration. A nonperturbative approach is used to describe the electron-photon interaction by including the radiation field in an exact way via a laser-dressed interaction potential. Through a variational approach we evaluate the donor binding energy. We find that the interaction strength of the laser-dressed Coulomb potential in the z direction cannot only be enhanced but also weakened by the radiation field, while that in the x-y plane is only weakened. In this way, the binding energy of the states with odd z parity, like 2p(z) can be decreased or increased with respect to its static binding energy by the radiation field, while that of the other states can be only decreased. Furthermore, all binding energies become insensitive to the magnetic field if the radiation field is strong. The magnetopolaron effect on these energies is studied within second-order time-dependent perturbation theory. In the nonresonant region, a laser-modulated magnetopolaron correction, including the effect of single-photon processes, is observed. In the resonant region, a laser-modulated magnetopolaron effect, accompanied by the emission and absorption of a single photon, is found. Moreover, the 1s -> 2p(+) transition, accompanied by the emission of a single photon, is tuned by the radiation field into resonance with the longitudinal-optical phonon branch. This is electrically analogous to the magnetopolaron effect, and therefore we name it the dynamical magnetopolaron effect. Finally, by changing the frequency of the radiation field, these interesting effects can be tuned to be far away from the reststrahlen band and, therefore, can be detected experimentally. This in turn provides a direct measure of the electron-phonon interaction.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000457057500001 Publication Date 2019-01-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 7 Open Access
Notes ; This work was supported by National Natural Science Foundation of China (Grants No. 11404214, No. 11455015, and No. 61504016) and the China Scholarship Council (CSC), and Science and Technology Research Foundation of Jiangxi Provincial Education Department (Grants No. GJJ161062 and No. GJJ180868). B.V.D. was supported by the Research Foundation – Flanders (FWO-Vl) through a postdoctoral fellowship. ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:157555 Serial 5218
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Author Mohammed, M.; Verhulst, A.S.; Verreck, D.; Van de Put, M.L.; Magnus, W.; Sorée, B.; Groeseneken, G.
Title Phonon-assisted tunneling in direct-bandgap semiconductors Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 125 Issue (down) 1 Pages 015701
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In tunnel field-effect transistors, trap-assisted tunneling (TAT) is one of the probable causes for degraded subthreshold swing. The accurate quantum-mechanical (QM) assessment of TAT currents also requires a QM treatment of phonon-assisted tunneling (PAT) currents. Therefore, we present a multi-band PAT current formalism within the framework of the quantum transmitting boundary method. An envelope function approximation is used to construct the electron-phonon coupling terms corresponding to local Frohlich-based phonon-assisted inter-band tunneling in direct-bandgap III-V semiconductors. The PAT current density is studied in up to 100 nm long and 20 nm wide p-n diodes with the 2- and 15-band material description of our formalism. We observe an inefficient electron-phonon coupling across the tunneling junction. We further demonstrate the dependence of PAT currents on the device length, for our non-self-consistent formalism which neglects changes in the electron distribution function caused by the electron-phonon coupling. Finally, we discuss the differences in doping dependence between direct band-to-band tunneling and PAT current. Published under license by AIP Publishing.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000455350200021 Publication Date 2019-01-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 2 Open Access
Notes ; This work was supported by Imec's Industrial Affiliation Program. ; Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:156735 Serial 5224
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Author Rezvani, S.J.; Perali, A.; Fretto, M.; De Leo, N.; Flammia, L.; Milošević, M.; Nannarone, S.; Pinto, N.
Title Substrate-induced proximity effect in superconducting niobium nanofilms Type A1 Journal article
Year 2018 Publication Condensed Matter Abbreviated Journal
Volume 4 Issue (down) 1 Pages 4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Structural and superconducting properties of high-quality niobium nanofilms with different thicknesses are investigated on silicon oxide (SiO2) and sapphire substrates. The role played by the different substrates and the superconducting properties of the Nb films are discussed based on the defectivity of the films and on the presence of an interfacial oxide layer between the Nb film and the substrate. The X-ray absorption spectroscopy is employed to uncover the structure of the interfacial layer. We show that this interfacial layer leads to a strong proximity effect, especially in films deposited on a SiO2 substrate, altering the superconducting properties of the Nb films. Our results establish that the critical temperature is determined by an interplay between quantum-size effects, due to the reduction of the Nb film thicknesses, and proximity effects. The detailed investigation here provides reference characterizations and has direct and important implications for the fabrication of superconducting devices based on Nb nanofilms.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000464289300001 Publication Date 2018-12-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2410-3896 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes ; This project was financially supported by University of Camerino, FAR project CESEMN. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:159463 Serial 5233
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Author Li, H.; Zhang, L.; Li, L.; Wu, C.; Huo, Y.; Chen, Y.; Liu, X.; Ke, X.; Luo, J.; Van Tendeloo, G.
Title Two-in-one solution using insect wings to produce graphene-graphite films for efficient electrocatalysis Type A1 Journal article
Year 2019 Publication Nano Research Abbreviated Journal Nano Res
Volume 12 Issue (down) 1 Pages 33-39
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Natural organisms contain rich elements and naturally optimized smart structures, both of which have inspired various innovative concepts and designs in human society. In particular, several natural organisms have been used as element sources to synthesize low-cost and environmentally friendly electrocatalysts for the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries, which are clean energy devices. However, to date, no naturally optimized smart structures have been employed in the synthesis of ORR catalysts, including graphene-based materials. Here, we demonstrate a novel strategy to synthesize graphene-graphite films (GGFs) by heating butterfly wings coated with FeCl3 in N-2, in which the full power of natural organisms is utilized. The wings work not only as an element source for GGF generation but also as a porous supporting structure for effective nitrogen doping, two-dimensional spreading, and double-face exposure of the GGFs. These GGFs exhibit a half-wave potential of 0.942 V and a H2O2 yield of < 0.07% for ORR electrocatalysis; these values are comparable to those for the best commercial Pt/C and all previously reported ORR catalysts in alkaline media. This two-in-one strategy is also successful with cicada and dragonfly wings, indicating that it is a universal, green, and cost-effective method for developing high-performance graphene-based materials.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000453629900004 Publication Date 2018-08-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1998-0124 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.354 Times cited 7 Open Access Not_Open_Access
Notes ; The authors would like to thank Drs Qiang Wang and Wenjuan Yuan for useful discussions. This work was financially supported by the National Key R&D Program of China (No. 2017YFA0700104), the National Natural Science Foundation of China (Nos. 21601136 and 11404016), the National Program for Thousand Young Talents of China, Tianjin Municipal Education Commission, Tianjin Municipal Science and Technology Commission (No. 15JCYBJC52600), and the Fundamental Research Fund of Tianjin University of Technology. This work also made use of the resources of the National Center for Electron Microscopy in Beijing. ; Approved Most recent IF: 7.354
Call Number UA @ admin @ c:irua:156210 Serial 5265
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Author Michielsen, I.; Uytdenhouwen, Y.; Bogaerts, A.; Meynen, V.
Title Altering conversion and product selectivity of dry reforming of methane in a dielectric barrier discharge by changing the dielectric packing material Type A1 Journal article
Year 2019 Publication Catalysts Abbreviated Journal Catalysts
Volume 9 Issue (down) 1 Pages 51
Keywords A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We studied the influence of dense, spherical packing materials, with different chemical compositions, on the dry reforming of methane (DRM) in a dielectric barrier discharge (DBD) reactor. Although not catalytically activated, a vast effect on the conversion and product selectivity could already be observed, an influence which is often neglected when catalytically activated plasma packing materials are being studied. The alpha-Al2O3 packing material of 2.0-2.24 mm size yields the highest total conversion (28%), as well as CO2 (23%) and CH4 (33%) conversion and a high product fraction towards CO (similar to 70%) and ethane (similar to 14%), together with an enhanced CO/H-2 ratio of 9 in a 4.5 mm gap DBD at 60 W and 23 kHz. gamma-Al2O3 is only slightly less active in total conversion (22%) but is even more selective in products formed than alpha-Al2O3 BaTiO3 produces substantially more oxygenated products than the other packing materials but is the least selective in product fractions and has a clear negative impact on CO2 conversion upon addition of CH4. Interestingly, when comparing to pure CO2 splitting and when evaluating differences in products formed, significantly different trends are obtained for the packing materials, indicating a complex impact of the presence of CH4 and the specific nature of the packing materials on the DRM process.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000459732000051 Publication Date 2019-01-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2073-4344 ISBN Additional Links UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles
Impact Factor 3.082 Times cited 4 Open Access OpenAccess
Notes Approved Most recent IF: 3.082
Call Number UA @ admin @ c:irua:158666 Serial 5268
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Author Jia, W.-Z.; Zhang, Q.-Z.; Wang, X.-F.; Song, Y.-H.; Zhang, Y.-Y.; Wang, Y.-N.
Title Effect of dust particle size on the plasma characteristics in a radio frequency capacitively coupled silane plasma Type A1 Journal article
Year 2019 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 52 Issue (down) 1 Pages 015206
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Compared with dust-free plasmas, the existence of dust particles in plasmas may greatly influence the plasma properties. such as the plasma density, electron temperature, sheath properties, electron energy distribution function (EEDF) as well as the heating mechanism. In this work, a 1D hybrid fluid/MC model has been developed to investigate the interaction between dust and plasma in a low-pressure silane discharge sustained in a radio frequency capacitively coupled plasma, in which we assume spherical dust particles with a given radius are generated by taking the sum of the production rate of Si2H4- and Si2H5- as the nucleation rate. From our simulation, the plasma may experience definite perturbation by dust particles with a certain radius (more than 50nm) with an increase in electron temperature first, which further induces a rapid rise in the positive and negative ion densities. Then, the densities begin to decline due to the gradual lack of sufficient seed electrons. In addition, as the dust radius increases, the high energy tails of the EEDFs will be enhanced for discharge maintenance, accompanied by a decline in the population of low-energy electrons in comparison with those of pristine plasma. Furthermore, an obvious bulk heating is observed apart from the a-mode and local field reversal heating. This may contribute to the enhanced bulk electric field (also called the drift field) as a result of electron depletion via the dust. In addition, large-sized dust particles that accumulate near the sheaths tend to form two stable density peaks with their positions largely influenced by the time-averaged sheath thickness. A detailed study of the effects of the external parameters, including pressure, voltage and frequency, on the spatial distribution of dust particles is also conducted.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000448423800002 Publication Date 2018-10-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 2.588
Call Number UA @ admin @ c:irua:155361 Serial 5271
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Author Idrissi, H.; Ghidelli, M.; Béché, A.; Turner, S.; Gravier, S.; Blandin, J.-J.; Raskin, J.-P.; Schryvers, D.; Pardoen, T.
Title Atomic-scale viscoplasticity mechanisms revealed in high ductility metallic glass films Type A1 Journal article
Year 2019 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 9 Issue (down) 1 Pages 13426
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The fundamental plasticity mechanisms in thin freestanding Zr65Ni35 metallic glass films are investigated in order to unravel the origin of an outstanding strength/ductility balance. The deformation process is homogenous until fracture with no evidence of catastrophic shear banding. The creep/relaxation behaviour of the films was characterized by on-chip tensile testing, revealing an activation volume in the range 100–200 Å3. Advanced high-resolution transmission electron microscopy imaging and spectroscopy exhibit a very fine glassy nanostructure with well-defined dense Ni-rich clusters embedded in Zr-rich clusters of lower atomic density and a ~2–3 nm characteristic length scale. Nanobeam electron diffraction analysis reveals that the accumulation of plastic deformation at roomtemperature

correlates with monotonously increasing disruption of the local atomic order. These results provide experimental evidences of the dynamics of shear transformation zones activation in metallic glasses. The impact of the nanoscale structural heterogeneities on the mechanical properties including the rate dependent behaviour is discussed, shedding new light on the governing plasticity mechanisms in metallic glasses with initially heterogeneous atomic arrangement.
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Publisher Place of Publication Editor
Language Wos 000486139700008 Publication Date 2019-09-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited Open Access
Notes H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the FNRS under Grant PDR – T.0178.19. FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’) and Hercules fund ‘Direct electron detector for soft matter TEM’ from Flemish Government are acknowledged. Approved Most recent IF: 4.259
Call Number EMAT @ emat @c:irua:162786 Serial 5375
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Author Menezes, R.M.; Neto, J.F.S.; de Souza Silva, C.C.; Milošević, M.V.
Title Manipulation of magnetic skyrmions by superconducting vortices in ferromagnet-superconductor heterostructures Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 100 Issue (down) 1 Pages 014431
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Dynamics of magnetic skyrmions in hybrid ferromagnetic films harbors interesting physical phenomena and holds promise for technological applications. In this work, we discuss the behavior of magnetic skyrmions when coupled to superconducting vortices in a ferromagnet-superconductor heterostructure. We use numerical simulations and analytic arguments within London and Thiele formalisms to reveal broader possibilities for manipulating the skyrmion-vortex dynamic correlations in the hybrid system, that are not possible in its separated constituents. We explore the thresholds of particular dynamic phases, and quantify the phase diagram as a function of the relevant material parameters, applied current, and induced magnetic torques. Finally, we demonstrate the broad and precise tunability of the skyrmion Hall angle in the presence of vortices, with respect to currents applied to either or both the superconductor and the ferromagnet within the heterostructure.
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Publisher Place of Publication Editor
Language Wos 000477883500004 Publication Date 2019-07-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 17 Open Access
Notes ; This work was supported by the Research Foundation – Flanders (FWO-Vlaanderen) and Brazilian Agencies Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco (FACEPE, under Grant No. APQ-0198-1.05/14), Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq). ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:161890 Serial 5421
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Author Scot, V.; Fernandez, J.E.; Vincze, L.; Janssens, K.
Title 3D extension of the Monte Carlo code MCSHAPE for photon-matter interactions in the heterogeneous media Type A1 Journal article
Year 2007 Publication Nuclear instruments & methods in physics research section B-Beam interactions with materiala and atoms Abbreviated Journal
Volume 263 Issue (down) 1 Pages 204-208
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
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Publisher Place of Publication Editor
Language Wos 000250798000042 Publication Date 2007-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 15 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:66755 Serial 5448
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Author Krupińska, B.; Worobiec, A.; Rotondo, G.G.; Novaković, V.; Kontozova, V.; Ro, C.-U.; Van Grieken, R.; De Wael, K.
Title Assessment of the air quality (NO2, SO2, O3 and particulate matter) in the Plantin-Moretus Museum/Print Room in Antwerp, Belgium, in different seasons of the year Type A1 Journal article
Year 2012 Publication Microchemical journal Abbreviated Journal Microchem J
Volume 102 Issue (down) 1 Pages 49-53
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract The Plantin-Moretus Museum/Print Room in Antwerp, Belgium, gathers one of the most precious collections of typographical material and old printed books in the world. Rich decorations of this former printing-house and the history of the building itself underline its uniqueness. The cultural heritage (CH) objects collected in the museum, in particular books and manuscripts are vulnerable to the atmospheric pollution and can be irreversibly damaged. To assess the air quality inside the museum, four consecutive sampling campaigns were performed in each season of the year. The gas monitoring of nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3) was carried out outside the building, in galleries and in showcases by means of using diffusive samplers. The particulate matter (PM) was collected in bulk form and as single particles and then analysed with use of energy dispersive X-ray fluorescence (EDXRF) and electron probe micro-analyser (EPMA), respectively. The museum complex turned out to show good protection against gaseous pollutants, especially SO2 and O3. The concentrations of these pollutants were significantly reduced inside the building in comparison to the outdoor ones. Similar protective character of the museum complex was established in case of the coarse fraction of PM; however with some limitations. Single particle analysis showed that the relative abundance of carbon-rich particles inside the museum was greater than outside. Moreover, these particles contributed more to the fine fraction of PM than to the coarse fraction. Therefore, for better preservation of cultural heritage, special attention should be paid to the small particles and their distribution within the museum.
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Language Wos 000301559100007 Publication Date 2011-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.034 Times cited 25 Open Access
Notes ; The presented work was realised in the frame of the project Preventive conservation/preservation in the museum Plantin-Moretus/Prentenkabinet, Antwerp, financed by the Flemish Government. Special thanks are due to Mrs Hanne Moris and Mrs Elke van Herck and all the staff of the Museum Plantin-Moretus/Print Room in Antwerp for their sincere interest in this work and their eager assistance during all the sampling campaigns. Barbara Krupinska is supported as PhD student by the Flemish Fund for Scientific Research (FWO, Belgium). ; Approved Most recent IF: 3.034; 2012 IF: 2.879
Call Number UA @ admin @ c:irua:94466 Serial 5483
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Author van Espen, P.; Janssens, K.; Nobels, J.
Title AXIL-PC, software for the analysis of complex-x-ray spectra Type A1 Journal article
Year 1986 Publication Chemometrics and intelligent laboratory systems Abbreviated Journal
Volume 1 Issue (down) 1 Pages 109-114
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
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Publisher Place of Publication Editor
Language Wos A1986K579000015 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0169-7439 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:149781 Serial 5487
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Author Simoen, J.; De Meyer, S.; Vanmeert, F.; De Keyser, N.; Avranovich, E.; van der Snickt, G.; Van Loon, A.; Keune, K.; Janssens, K.
Title Combined Micro- and Macro scale X-ray powder diffraction mapping of degraded Orpiment paint in a 17th century still life painting by Martinus Nellius Type A1 Journal article
Year 2019 Publication Heritage science Abbreviated Journal
Volume 7 Issue (down) 1 Pages 83
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract The spontaneous chemical alteration of artists' pigment materials may be caused by several degradation processes. Some of these are well known while others are still in need of more detailed investigation and documentation. These changes often become apparent as color modifications, either caused by a change in the oxidation state in the original material or the formation of degradation products or salts, via simple or more complex, multistep reactions. Arsenic-based pigments such as orpiment (As2S3) or realgar (alpha-As4S4) are prone to such alterations and are often described as easily oxidizing upon exposure to light. Macroscopic X-ray powder diffraction (MA-XRPD) imaging on a sub area of a still life painting by the 17th century Dutch painter Martinus Nellius was employed in combination with microscopic (mu-) XRPD imaging of a paint cross section taken in the area imaged by MA-XRPD. In this way, the in situ formation of secondary metal arsenate and sulfate species and their migration through the paint layer stack they originate from could be visualized. In the areas originally painted with orpiment, it could be shown that several secondary minerals such as schultenite (PbHAsO4), mimetite (Pb-5(AsO4)(3)Cl), palmierite (K2Pb(SO4)(2)) and syngenite (K2Ca(SO4)(2)center dot H2O) have formed. Closer inspection of the cross-sectioned paint layer stack with mu-XRPD illustrates that the arsenate minerals schultenite and mimetite have precipitated at the interface between the orpiment layer and the layer below that is rich in lead white, i.e. close to the depth of formation of the arsenate ions. The sulfate palmierite has mostly precipitated at the surface and upper layers of the painting.
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Publisher Place of Publication Editor
Language Wos 000490592700001 Publication Date 2019-10-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes ; The authors acknowledge financial support from the NWO (The Hague) Science4Arts 'ReVisRembrandt' project (AvL, JD), the GOA Project Solarpaint (University of Antwerp Research Council) (SdM) and the METOX project (Belgian Federal Science Policy) (FvM). Special thanks go to the support received from FWO, Brussels via projects G056619 N and G054719 N (GvdS, KJ) and from NWO, The Hague via project NICAS/3D2P (KK, NdK). Parts of the MA-XRPD scanner could be purchased thanks to InterReg Project Smart*Light. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:163693 Serial 5521
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Author Bichlmeier, S.; Janssens, K.; Heckel, J.; Hoffmann, P.; Ortner, H.M.
Title Comparative material characterization of historical and industrial samples by using a compact micro-XRF spectrometer Type A1 Journal article
Year 2002 Publication X-ray spectrometry Abbreviated Journal X-Ray Spectrom
Volume 31 Issue (down) 1 Pages 87-91
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000173653400016 Publication Date 2002-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0049-8246 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.298 Times cited 12 Open Access
Notes Approved Most recent IF: 1.298; 2002 IF: 1.574
Call Number UA @ admin @ c:irua:36670 Serial 5529
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Author Hellar-Kihampa, H.; Potgieter-Vermaak, S.; De Wael, K.; Lugwisha, E.; van Espen, P.; Van Grieken, R.
Title Concentration profiles of metal contaminants in fluvial sediments of a rural-urban drainage basin in Tanzania Type A1 Journal article
Year 2014 Publication International journal of environmental analytical chemistry Abbreviated Journal Int J Environ An Ch
Volume 94 Issue (down) 1 Pages 77-98
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This study investigated concentration profiles of trace, rare earth and platinum group metals in fluvial sediments from the Pangani river basin (43,650 km2), one of the largest river basins in Tanzania, to assess its environmental quality. Sediment samples were collected in two distinct seasons from 12 representative sites of diverse land-use practices and characterised by ICP-MS after optimised microwave digestion. Ecological risks were assessed by evaluation of pollution index and comparison with legislated sediment quality guidelines (SQG). The results revealed contamination by some trace metals (e.g. Pb, V, Cu, Cr, Ni, Cd, As, Co, Mn and Zn) in concentrations ranging from 0.7 to 2940 mg kg−1, and four rare earth elements (Y, Ce, Nd, Yb) in concentrations ranging from 0.9 (Yb) to 500 mg kg−1 dry weight (Ce), which significantly exceeded the estimated background values at some stations. Palladium was the only platinum group element that was detected in quantifiable concentrations (0.33.5 mg kg−1). Concentrations of some trace metals exceeded the SQGs at some localised areas. Principal component analysis and multivariate correlations indicated geochemical characteristics of the area as the major control of metal concentrations and spatial variability. Organic matter and clay contents also played a significant role in metal distributions. Assessment of land-use practices upstream of the sampling locations was used to trace potential anthropogenic sources of metal enrichments, where highest levels were found in areas close to urban centres and agricultural activities. The study provides baseline data for future monitoring programs, and highlights the need for more comprehensive analysis involving a wider spatio-temporal scale and ecotoxicological risk assessment.
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Language Wos 000329774500007 Publication Date 2013-05-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0306-7319 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.208 Times cited 5 Open Access
Notes ; The participants of this research gratefully acknowledge the financial support of the Belgian Development Agency (BTC). The contribution of the Pangani Basin Water Board (PBWB), especially Ms Arafa Maggidi in provision of valuable information and assistance with the sampling campaigns is greatly appreciated. We sincerely acknowledge the assistance of Mr. Elisa Dunstan Kiwelu of Ardhi University, Dar es Salaam, Tanzania in mapping the study area; Mr Peter Machibya of the Department of Geology, University of Dar es Salaam, Tanzania in sediment characterisation; and Dr Valentine Kayawe Mubiana of the Department of Biology, University of Antwerp in ICP-MS analysis. The contributions of six anonymous reviewers, which greatly improved the manuscript for this paper, are highly appreciated. ; Approved Most recent IF: 1.208; 2014 IF: 1.295
Call Number UA @ admin @ c:irua:109234 Serial 5547
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Author Mudronja, D.; Vanmeert, F.; Hellemans, K.; Fazinic, S.; Janssens, K.; Tibljas, D.; Rogosic, M.; Jakovljevic, S.
Title Efficiency of applying ammonium oxalate for protection of monumental limestone by poultice, immersion and brushing methods Type A1 Journal article
Year 2013 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
Volume 111 Issue (down) 1 Pages 109-119
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Samples of cretaceous limestone have been treated with three application methods (poultice, immersion and brushing) using different concentrations of ammonium oxalate solution (AmOx) and varying treatment time in order to test the efficiency of surface and in-depth formation of a protective layer of calcium oxalate (CaOx). Synchrotron-based microanalytical techniques (SR-mu XRD with 12.5 mu mx7.5 mu m (HxV) probe size, SR-mu FTIR with 10 mu mx10 mu m and 8 mu mx20 mu m probe sizes) and laboratory mu FTIR, XRD and SEM have been employed for analysis of the treated samples. Synchrotron-based techniques showed variations in the CaOx distribution along the surface on a micrometer scale. All treatments resulted in the development of a CaOx layer with a maximum thickness of approximately 40 mu m. Application by the brushing method with 10 1-min applications with 5-min breaks during one hour showed a development of the calcium oxalate layer equivalent to the poultice treatment taking 10 h. This treatment could be preferred for large marble or limestone surfaces where poultice usage is economically not feasible.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000316075700014 Publication Date 2012-10-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.455 Times cited 13 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) project nos. G.0704.08 and G.01769.09. The research leading to these results has received financial support by the Access to Research Infrastructures activity in the 7th Framework Programme of the EU (CHARISMA Grant Agreement No. 228330). ; Approved Most recent IF: 1.455; 2013 IF: 1.694
Call Number UA @ admin @ c:irua:108262 Serial 5584
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Author Elia, A.; De Wael, K.; Dowsett, M.; Adriaens, A.
Title Electrochemical deposition of a copper carboxylate layer on copper as potential corrosion inhibitor Type A1 Journal article
Year 2011 Publication Journal of solid state electrochemistry Abbreviated Journal J Solid State Electr
Volume 16 Issue (down) 1 Pages 143-148
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Carboxylic acids and sodium carboxylates are used to protect metals against aqueous and atmospheric corrosion. In this paper, we describe the application of a layer of copper carboxylate on the surface of a copper electrode by means of cyclic voltammetry technique and tests which measure the corresponding resistance to aqueous corrosion. Unlike the soaking process, which also forms a film on the surface, the use of cyclic voltammetry allows one to follow the deposition process of the copper carboxylates onto the electrode. The modified electrodes have been characterised with infrared spectroscopy. In addition, the corrosion resistance of the film has been investigated using polarisation resistance and Tafel plot measurements.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000298651700018 Publication Date 2011-01-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1432-8488 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.316 Times cited 8 Open Access
Notes ; Authors would like to acknowledge the Research Foundation-Flanders (FWO) for funding assistance (A. Elia is a FWO aspirant) and V. Vermeersch and S. Van Vlierberghe (Ghent University, Polymer Chemistry and Biomaterials Research Group) for the FTIR-ATR measurements. ; Approved Most recent IF: 2.316; 2011 IF: 2.131
Call Number UA @ admin @ c:irua:89618 Serial 5588
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Author van der Snickt, G.; Martins, A.; Delaney, J.; Janssens, K.; Zeibel, J.; Duffy, M.; McGlinchey, C.; Van Driel, B.; Dik, J.
Title Exploring a hidden painting below the surface of Rene Magritte's Le Portrait Type A1 Journal article
Year 2016 Publication Applied spectroscopy Abbreviated Journal Appl Spectrosc
Volume 70 Issue (down) 1 Pages 57-67
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Two state-of-the-art methods for non-invasive visualization of subsurface (or overpainted) pictorial layers present in painted works of art are employed to study Le portrait, painted by Belgian artist Rene Magritte in 1935. X-ray radiography, a commonly used method for the nondestructive inspection of paintings, had revealed the presence of an underlying figurative composition, part of an earlier Magritte painting entitled La pose enchantee (1927) which originally depicted two full length nude female figures with exaggerated facial features. On the one hand, macroscopic X-ray fluorescence analysis (MA-XRF), a method capable of providing information on the distribution of the key chemical elements present in many artists' pigments, was employed. The ability of the X-rays to penetrate the upper layer of paint enabled the imaging of the facial features of the female figure and provided information on Magritte's palette for both surface and hidden composition. On the other hand, visible and near infrared hyperspectral imaging spectroscopies in transmission mode were also used, especially in the area of the table cloth in order to look through the upper representation and reveal the pictorial layer(s) below. MA-XRF provided elemental information on the pigment distributions in both the final painting and the prior whereas the transmission mode provided information related to preparatory sketches as well as revealing differences between the paints used in both compositions. These results illustrate very well the manner in which the two imaging methods complement each other, both in the sense of providing different types of information on the nature and presence of paint components/pigments and in the sense of being optimally suited to easily penetrate through different types of overpaint.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368604500007 Publication Date 2016-01-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-7028 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.529 Times cited 13 Open Access
Notes ; GvdS and KJ acknowledge the support of the Fund Inbev-Baillet Latour. JKD acknowledges support from the Andrew Mellon Foundation and the National Science Foundation. BvD and JD acknowledge support from The Netherlands Organisation for Scientific Research (NWO). ; Approved Most recent IF: 1.529
Call Number UA @ admin @ c:irua:131544 Serial 5620
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Author Falkenberg, G.; Fleissner, G.E.; Fleissner, G.U.E.; Schuchardt, K.; Kühbacher, M.; Chalmin, E.; Janssens, K.
Title High resolution micro-XRF maps of iron oxides inside sensory dendrites of putative avian magnetoreceptors Type A1 Journal article
Year 2009 Publication Journal of physics : conference series Abbreviated Journal
Volume 186 Issue (down) 1 Pages 012084-3
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Iron mineral containing sensory dendrites in the inner lining of the upper beak of homing pigeons [1] and various bird species [2] are the first candidate structures for an avian magnetic field receptor. A new concept of magnetoreception [3, 4] is based on detailed ultra-structural optical and electron microscopy analyses in combination with synchrotron radiation microscopic X-ray fluorescence analysis (micro-XRF) and microscopic X-ray absorption near edge structures (micro-XANES). Several behavioral experiments [5, 6] and first mathematical simulations [6] affirm our avian magnetoreceptor model. The iron minerals inside the dendrites are housed in three different subcellular compartments (bullets, platelets, vesicles), which could be clearly resolved and identified by electron microscopy on ultrathin sections [1, 3]. Micro-XRF and micro-XANES data obtained at HASYLAB beamline L added information about the elemental distribution and Fe speciation [3], but are averaged over the complete dendrite due to limited spatial resolution. Here we present recently performed micro-XRF maps with sub-micrometer resolution (ESRF ID21), which reveal for the first time subcellular structural information from almost bulk-like dendrite sample material. Due to the thickness of 30 μm the microarchitecture of the dendrites can be considered as undisturbed and artefacts introduced by sectioning might be widely reduced.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000282023900084 Publication Date 2009-09-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588; 1742-6596 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:111317 Serial 5642
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Author De Meyer, S.; Vanmeert, F.; Vertongen, R.; van Loon, A.; Gonzalez, V.; van der Snickt, G.; Vandivere, A.; Janssens, K.
Title Imaging secondary reaction products at the surface of Vermeer's Girl with the Pearl Earring by means of macroscopic X-ray powder diffraction scanning Type A1 Journal article
Year 2019 Publication Heritage science Abbreviated Journal
Volume 7 Issue (down) 1 Pages 67
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract The use of non-invasive macroscopic imaging techniques is becoming more prevalent in the field of cultural heritage, especially to avoid invasive procedures that damage valuable artworks. For this purpose, an X-ray powder diffraction scanner (MA-XRPD) capable of visualising crystalline compounds in a highly specific manner was recently developed. Many inorganic pigments present in paintings fall into this category of materials. In this study, the 17th century oil painting Girl with a Pearl Earring (c. 1665) by Johannes Vermeer was analysed with a combination of transmission and reflection mode MA-XRPD. By employing this scanner in reflection mode, the relative sensitivity for compounds that are present at the paint surface could be increased, establishing it as a highly relevant technique for investigating the degradation processes that are ongoing at paint surfaces. Many of the original pigments employed by Vermeer could be identified, along with four secondary alteration products: gypsum (CaSO4 center dot 2H(2)O), anglesite (PbSO4), palmierite (K2Pb(SO4)(2)) and weddellite (CaC2O4 center dot 2H(2)O). The formation of gypsum was linked to the presence of chalk in the upper glaze layer while the formation of palmierite and weddellite is driven by the presence of lake pigments (and their substrates). In this manner, MA-XRPD can also be used to pinpoint locations relevant for sampling and synchrotron mu-XRPD analysis, which provides information on the microscopic make-up of the paint. A paint cross-section taken from an area rich in palmierite was analysed with synchrotron mu-XRPD, which confirmed the presence of this secondary compound at the interface of the upper paint layer with the ground layer as well as the presence of anglesite in the ground layer. The capacity of MA-XRPD to identify and chart secondary alteration products in a non-invasive manner has only very recently been demonstrated and makes it a highly relevant technique for the assessment of the chemical condition of works of art.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000484938100001 Publication Date 2019-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access
Notes ; The authors would like to thank Interreg Vlaanderen-Nederland for funding to help develop the MA-rXRPD scanner. This project was made possible with support from the Johan Maurits Compagnie Foundation. This study was supported by Interreg and CALIPSOplus (Grant 730872). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:162801 Serial 5653
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Author Pei, Z.-G.; Shan, X.-Q.; Zhang, S.-Z.; Kong, J.-J.; Wen, B.; Zhang, J.; Zheng, L.-R.; Xie, Y.-N.; Janssens, K.
Title Insight to ternary complexes of co-adsorption of norfloxacin and Cu(II) onto montmorillonite at different pH using EXAFS Type A1 Journal article
Year 2011 Publication Journal of hazardous materials Abbreviated Journal J Hazard Mater
Volume 186 Issue (down) 1 Pages 842-848
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Co-adsorption of norfloxacin (Nor) and Cu(II) on montmorillonite at pH 4.5, 7.0 and 9.0 was studied by integrated batch adsorption experiments and extended X-ray absorption fine structure (EXAFS) spectroscopy. Under such pH conditions the dominant species of Nor are cation (Nor+), zwitterion (Nor±), and anion (Nor−), respectively. Results indicated that Nor sorption decreased with an increase of solution pH. The presence of Cu(II) slightly suppressed the Nor+ sorption at pH 4.5, while increased Nor± and Nor−sorption on montmorillonite at pH 7.0 and 9.0, respectively. In contrast, Nor increased Cu(II) adsorption at pH 4.5, but had little effect on the adsorption of Cu(II) on montmorillonite at pH 7.0 and 9.0. Spectroscopic results showed that, at pH 4.5, Nor+ was sorbed on montmorillonite by the formation of outer-sphere montmorilloniteNorCu(II) ternary surface complex. At pH 7.0, montmorilloniteNorCu(II) and montmorilloniteCu(II)Nor ternary surface complexes co-exist. At pH 9.0, montmorilloniteCu(II)Nor ternary surface complex was likely formed, which was different to Cu(II)(Nor)2 precipitate of the solution.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000288102400107 Publication Date 2010-11-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3894 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.065 Times cited 25 Open Access
Notes ; This work was funded by the National Natural Science Foundation of China (grant numbers: 41071308, 20707037, 20737003 and 20877087) and the Youth Fund of State Key Laboratory of Environmental Chemistry and Ecotoxicology QN2009-07. ; Approved Most recent IF: 6.065; 2011 IF: 4.173
Call Number UA @ admin @ c:irua:88786 Serial 5664
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Author Peeters, J.; Steenackers, G.; Sfarra, S.; Legrand, S.; Ibarra-Castanedo, C.; Janssens, K.; van der Snickt, G.
Title IR reflectography and active thermography on artworks : the added value of the 1.53 µm band Type A1 Journal article
Year 2018 Publication Applied Sciences Abbreviated Journal Appl Sci-Basel
Volume 8 Issue (down) 1 Pages 50
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Infrared Radiation (IR) artwork inspection is typically performed through active thermography and reflectography with different setups and cameras. While Infrared Radiation Reflectography (IRR) is an established technique in the museum field, exploiting mainly the IR-A (0.71.4 µm) band to probe for hidden layers and modifications within the paint stratigraphy system, active thermography operating in the IR-C range (35 μ m) is less frequently employed with the aim to visualize structural defects and features deeper inside the build-up. In this work, we assess to which extent the less investigated IR-B band (1.53 μ m) can combine the information obtained from both setups. The application of IR-B systems is relatively rare as there are only a limited amount of commercial systems available due to the technical complexity of the lens coating. This is mainly added as a so-called broadband option on regular Mid-wave infrared radiation (MWIR) (IR-C/35 μ m) cameras to increase sensitivity for high temperature applications in industry. In particular, four objects were studied in both reflectographic and thermographic mode in the IR-B spectral range and their results benchmarked with IR-A and IR-C images. For multispectral application, a single benchmark is made with macroscopic reflection mode Fourier transform infrared (MA-rFTIR) results. IR-B proved valuable for visualisation of underdrawings, pencil marks, canvas fibres and wooden grain structures and potential pathways for additional applications such as pigment identification in multispectral mode or characterization of the support (panels, canvas) are indicated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000424388800050 Publication Date 2018-01-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2076-3417 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.679 Times cited 4 Open Access
Notes ; This research has been funded by the University of Antwerp and the Institute for the Promotion of Innovation by Science and Technology in Flanders (VLAIO) by the support to the TETRA project 'SINT: Smart Integration of Numerical modelling and Thermal inspection' with project number HBC.2017.0032. Furthermore, the research leading to these results has received funding from the Research Foundation Flanders (FWO) travel grant V4.010.16N and the Stimpro stimuli of UAntwerpen under project ID 32864. We would like to end with a special thanks to the MiViM research chair of Prof. Xavier Maldague and the support of the full team in supporting the preliminary measurements of this research. ; Approved Most recent IF: 1.679
Call Number UA @ admin @ c:irua:149164 Serial 5677
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Author Zanin, L.; Tomasi, N.; Rizzardo, C.; Gottardi, S.; Terzano, R.; Alfeld, M.; Janssens, K.; De Nobili, M.; Mimmo, T.; Cesco, S.
Title Iron allocation in leaves of Fe-deficient cucumber plants fed with natural Fe complexes Type A1 Journal article
Year 2015 Publication Physiologia plantarum Abbreviated Journal Physiol Plantarum
Volume 154 Issue (down) 1 Pages 82-94
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Iron (Fe) sources available for plants in the rhizospheric solution are mainly a mixture of complexes between Fe and organic ligands, including phytosiderophores (PS) and water-extractable humic substances (WEHS). In comparison with the other Fe sources, Fe-WEHS are more efficiently used by plants, and experimental evidences show that Fe translocation contributes to this better response. On the other hand, very little is known on the mechanisms involved in Fe allocation in leaves. In this work, physiological and molecular processes involved in Fe distribution in leaves of Fe-deficient Cucumis sativus supplied with Fe-PS or Fe-WEHS up to 5days were studied combining different techniques, such as radiochemical experiments, synchrotron micro X-ray fluorescence, real-time reverse transcription polymerase chain reaction and in situ hybridization. In Fe-WEHS-fed plants, Fe was rapidly (1day) allocated into the leaf veins, and after 5days, Fe was completely transferred into interveinal cells; moreover, the amount of accumulated Fe was much higher than with Fe-PS. This redistribution in Fe-WEHS plants was associated with an upregulation of genes encoding a ferric(III)-chelate reductase (FRO), a Fe2+ transporter (IRT1) and a natural resistance-associated macrophage protein (NRAMP). The localization of FRO and IRT1 transcripts next to the midveins, beside that of NRAMP in the interveinal area, may suggest a rapid and efficient response induced by the presence of Fe-WEHS in the extra-radical solution for the allocation in leaves of high amounts of Fe. In conclusion, Fe is more efficiently used when chelated to WEHS than PS and seems to involve Fe distribution and gene regulation of Fe acquisition mechanisms operating in leaves.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000353067500007 Publication Date 2014-10-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-9317 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.33 Times cited 14 Open Access
Notes ; Research was supported by grants from Italian MIUR (FIRB-Programma 'Futuro in Ricerca') and Free University of Bolzano (TN5056). Synchrotron experiments at HASYLAB were financially supported by the European Community-Research Infrastructure Action under the FP6 'Structuring the European Research Area' Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). We thank Karen Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; Approved Most recent IF: 3.33; 2015 IF: 3.138
Call Number UA @ admin @ c:irua:132500 Serial 5678
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Author Trashin, S.; De Jong, M.; Breugelmans, T.; Pilehvar, S.; De Wael, K.
Title Label-free impedance aptasensor for major peanut allergen Ara h 1 Type A1 Journal article
Year 2015 Publication Electroanalysis Abbreviated Journal
Volume 27 Issue (down) 1 Pages 32-37
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Applied Electrochemistry & Catalysis (ELCAT)
Abstract The peanut allergen Ara h 1 belonging to the vicilin family of seed storage proteins is known to be a suitable marker for peanut detection in foods. In the present work, we suggest an electrochemical detection of Ara h 1 using a recently selected 80-base DNA aptamer. The detection strategy relies on insulation effect of a bulky protein captured by an immobilized aptamer. The electrodes were modified by the aptamer and characterized using electrochemical impedance spectroscopy (EIS). The aptamer surface density and analytical parameters of the calibration curves for Ara h 1 were compared with the system prepared with thrombin binding aptamer (TBA) and operated in the same conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000347838300004 Publication Date 2014-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 10 Open Access
Notes ; ST greatly appreciates the Research Council University of Antwerp (IWS BOF UA) for funding the post-doctoral fellowship. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:119442 Serial 5686
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Author Buczyńska, A.J.; Geypens, B.; Van Grieken, R.; De Wael, K.
Title Large-volume injection combined with gas chromatography/isotope ratio mass spectrometry for the analysis of polycyclic aromatic hydrocarbons Type A1 Journal article
Year 2014 Publication Rapid communications in mass spectrometry Abbreviated Journal Rapid Commun Mass Sp
Volume 28 Issue (down) 1 Pages 1-9
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract RATIONALE: Compound-specific stable isotope analyses of carbon require relatively large amounts of sample for reliable analyses. Commonly applied injections of 1 μL may thus be inefficient for samples with low concentrations of pollutants (e.g. air particulate matter) or when the amount of a sample is limited. METHODS: A Large-Volume Injection (LVI) method for carbon stable isotope ratio analysis of Polycyclic Aromatic Hydrocarbons (PAHs) was optimized in this study. Gas chromatography/combustion/isotope ratio mass spectrometry (GCCIRMS) and ion trap mass spectrometry (ITMS) were used for the determination of stable carbon isotope ratios and quantification of compounds, respectively. RESULTS: The optimized method resulted in very good reproducibility, even for the most volatile PAH, naphthalene, when a small amount of higher boiling co-solvent was used. No significant fractionation of isotope ratios could be seen and the recoveries of analytes were similar to or better than that of a splitless cold injection. CONCLUSIONS: Injection of 100 μL, instead of the commonly used 1 μL, increases the detection limit for PAHs significantly and/or simplifies the sample preparation step. Using our optimized method, stable carbon isotope ratios can be reliably measured in samples with concentrations of PAHs down to 0.050.1 ng μL1.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000328248300007 Publication Date 2013-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0951-4198 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.998 Times cited 5 Open Access
Notes ; ; Approved Most recent IF: 1.998; 2014 IF: 2.253
Call Number UA @ admin @ c:irua:111677 Serial 5689
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Author Cotte, M.; Checroun, E.; De Nolf, W.; Taniguchi, Y.; De Viguerie, L.; Burghammer, M.; Walter, P.; Rivard, C.; Salome, M.; Janssens, K.; Susini, J.
Title Lead soaps in paintings : friends or foes? Type A1 Journal article
Year 2017 Publication Studies in conservation Abbreviated Journal Stud Conserv
Volume 62 Issue (down) 1 Pages 2-23
Keywords A1 Journal article; Art; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The origin(s) and role(s) of metal soaps in paints are a worldwide concern today. These hybrid compounds, containing both fatty acid chains and metals associated with a carboxylate function, are increasingly identified in paints. As reviewed in the first part of this work, the presence of metal soaps in paints is differently interpreted in scientific publications: metal soaps are sometimes considered to play a positive role as anchor points, during paint drying processes; they can also be considered as responsible for many degradation processes (protrusions, efflorescences, darkening, etc.). Their origins are also interpreted in various ways. In some paintings (in particular from the twentieth century), they have sometimes introduced on purpose, as additives, to modify the physical properties of the painting materials. In older paintings, metal soaps are usually thought to result from an uncontrolled reaction of oil with lead-based pigments, in particular lead white, red lead, and lead tin yellow. In the second part of this work, the review of historical recipes of lead-based paint shows an important number of recipes based on controlled mixing of oil with lead driers. In the third part, the experimental reproduction of such traditional recipes using walnut oil and litharge (PbO) shows that lead soaps can be formed, both in about one hour at approximate to 100 degrees C, or in about one month at room temperature. It shows as well that after a few years, litharge is no longer detected in the paint medium, while different lead carbonates are. Finally, the micro-infrared spectroscopy and micro-X-ray diffraction re-analysis of protrusions from a nine-year model painting shows together with lead soaps, the presence of Pb-5(CO3)(3)(OH)(2)O ('synthetic plumbonacrite'), an unusual phase recently observed in a protrusion from a painting by Vincent Van Gogh. This work highlights (i) the multiple origins and roles of metal soaps in paints and (ii) the importance of combining the analysis of fragments from historical paintings with the analysis and reproduction of historical recipes. In particular, we show that the components detected today in historical paintings may severely differ from those originally used or prepared by the painter, complicating the assessment of the painter's intentions. More than the presence of metal soaps, the key questions to be tackled should be about their origins and (re)mobilization.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000393691200002 Publication Date 2016-10-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-3630; 2047-0584 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 0.578 Times cited 26 Open Access
Notes ; This work was supported by the European Synchrotron Radiation Facility. ; Approved Most recent IF: 0.578
Call Number UA @ admin @ c:irua:141976 Serial 5690
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Author van der Snickt, G.; de Nolf, W.; Vekemans, B.; Janssens, K.
Title μ-XRF/μ-RS vs. SR μ-XRD for pigment identification in illuminated manuscripts Type A1 Journal article
Year 2008 Publication Applied physics A : materials science & processing Abbreviated Journal Appl Phys A-Mater
Volume 92 Issue (down) 1 Pages 59-68
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract For the non-destructive identification of pigments and colorants in works of art, in archaeological and in forensic materials, a wide range of analytical techniques can be used. Bearing in mind that every method holds particular limitations, two complementary spectroscopic techniques, namely confocal ì-Raman spectroscopy (ì-RS) and ì-X-ray fluorescence spectroscopy (ì-XRF), were joined in one instrument. The combined ì-XRF and ì-RS device, called PRAXIS unites both complementary techniques in one mobile setup, which allows ì- and in situ analysis. ì-XRF allows one to collect elemental and spatially-resolved information in a non-destructive way on major and minor constituents of a variety of materials. However, the main disadvantages of ì-XRF are the penetration depth of the X-rays and the fact that only elements and not specific molecular combinations of elements can be detected. As a result ì-XRF is often not specific enough to identify the pigments within complex mixtures. Confocal Raman microscopy (ì-RS) can offer a surplus as molecular information can be obtained from single pigment grains. However, in some cases the presence of a strong fluorescence background limits the applicability. In this paper, the concrete analytical possibilities of the combined PRAXIS device are evaluated by comparing the results on an illuminated sheet of parchment with the analytical information supplied by synchrotron radiation ì-X-ray diffraction (SR ì-XRD), a highly specific technique.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000256426000008 Publication Date 2008-03-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.455 Times cited 56 Open Access
Notes Approved Most recent IF: 1.455; 2008 IF: 1.884
Call Number UA @ admin @ c:irua:74465 Serial 5695
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Author Schalm, O.; Proost, K.; De Vis, K.; Cagno, S.; Janssens, K.; Mees, F.; Jacobs, P.; Caen, J.
Title Manganese staining of archaeological glass : the characterization of Mn-rich inclusions in leached layers and a hypothesis of its formation Type A1 Journal article
Year 2011 Publication Archaeometry Abbreviated Journal Archaeometry
Volume 53 Issue (down) 1 Pages 103-122
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract During the study of a large number of archaeological glass fragments, manganese-rich inclusions in leached layers were observed in a limited number of cases. This phenomenon occurs only in black-coloured leached layers. Since the formation mechanism of such manganese-rich inclusions is still unclear, a combination of several analytical techniques was used in order to investigate this phenomenon and, more specifically, to obtain more information on (a) the composition and morphology of the inclusions, (b) the chemical state of Mn and (c) the 3D morphology of the inclusions. A mechanism that might explain the formation of these inclusions is proposed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000285418100006 Publication Date 2010-07-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-813x; 1475-4754 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.47 Times cited 24 Open Access
Notes ; ; Approved Most recent IF: 1.47; 2011 IF: 1.183
Call Number UA @ admin @ c:irua:88754 Serial 5704
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Author Jochum, K.P.; Dingwell, D.B.; Rocholl, A.; Janssens, K.; Vincze, L.; et al.
Title The preparation and preliminary characterisation of eight geological MPI-DING reference glasses for in-site microanalysis Type A1 Journal article
Year 2000 Publication Geostandards newsletter Abbreviated Journal
Volume 24 Issue (down) 1 Pages 87-133
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Eight silicate glasses were prepared by directly fusing and stirring 50-100 g each of basalt, andesite, komatiite, peridotite, rhyolite, and quartz-diorite. These are referred to as MPI-DING glasses and were made for the purpose of providing reference materials for geochemical, in-situ microanalytical work. Results from various analytical techniques indicate that individual glass fragments are well homogenised with respect to major and trace elements at the mu m to mm scale. Heterogeneities due to quench crystallisation of olivine have been observed in small and limited areas of the two komatiitic glasses. In order to obtain concentration values for as many elements as possible, the glasses were analysed by a variety of bulk and microanalytical methods in a number of laboratories. From the analytical data, preliminary reference values for more than sixty elements were calculated. The analytical uncertainties of most elements are estimated to be between 1% and 10%.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000088900000010 Publication Date 2007-05-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0150-5505 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:104244 Serial 5787
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Author Schepens, T.; Janssens, K.; Maes, S.; Wildemeersch, D.; Vellinga, J.; Jorens, P.G.; Saldien, V.
Title Respiratory muscle activity after spontaneous, neostigmine- or sugammadex-enhanced recovery of neuromuscular blockade : a double blind prospective randomized controlled trial Type A1 Journal article
Year 2019 Publication BMC anesthesiology Abbreviated Journal Bmc Anesthesiol
Volume 19 Issue (down) 1 Pages 187
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Background The use of neostigmine after neuromuscular blockade (NMB) has been associated with postoperative respiratory complications. In previous studies, we found lower diaphragmatic activity after neostigmine reversal of NMB, compared to sugammadex. It is still unclear whether the adequate use of neostigmine guarantees normal respiratory muscle function after NMB. In this study, we wanted to assess the effect of commonly used degrees of NMB and their possible reversal strategies on respiratory muscle activity after the return of normal neuromuscular transmission. Methods This is a randomized, controlled, parallel-group, single-centre, double-blind study in patients scheduled for intracranial surgery at a tertiary academic hospital in Belgium. All participants received target controlled propofol/remifentanil anesthesia and were randomized into one of five groups, receiving either a shallow NMB with no reversal (shallow/saline), a shallow NMB with sugammadex reversal (shallow/sugammadex), a moderate NMB with neostigmine reversal (moderate/neostigmine), a moderate NMB with sugammadex reversal (moderate/sugammadex), or a deep NMB with sugammadex reversal (deep/sugammadex). Primary and secondary outcome parameters were diaphragm and intercostal electromyographic (EMG) activity at the moment of resumed spontaneous breathing activity, defined as a maximal interval of 10 min after the first spontaneous breath. Results For the five groups, a total of 55 patients could be included in the final analysis. Median time of spontaneous breathing analyzed was 5 min (IQR 3-9.5 min). Both the moderate/sugammadex and the moderate/neostigmine groups had lower levels of diaphragm EMG compared to the shallow/sugammadex group. The moderate/neostigmine group had lower levels of intercostal EMG activity compared to the shallow/saline group. Conclusions In this study, the depth of neuromuscular blockade and type of reversal strategy impacts respiratory muscle activity at the moment of resumed spontaneous breathing and recovery of neuromuscular blockade. Both groups that received moderate NMB had lower levels of diaphragm EMG, compared to the shallow NMB group with sugammadex reversal. Compared to the shallow NMB group with no reversal, the moderate NMB with neostigmine reversal group had lower intercostal EMG activity.
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Publisher Place of Publication Editor
Language Wos 000490976800001 Publication Date 2019-10-19
Series Editor Series Title Abbreviated Series Title
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ISSN 1471-2253 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.525 Times cited Open Access
Notes ; This work was supported by an investigator-initiated project grant from Merck & Co (IISP 50678). Merck & Co had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. ; Approved Most recent IF: 1.525
Call Number UA @ admin @ c:irua:163713 Serial 5816
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Author Alfeld, M.; de Nolf, W.; Cagno, S.; Janssens, K.; et al.
Title Revealing hidden paint layers in oil paintings by means of scanning macro-XRF : a mock-up study based on Rembrandt's “An old man in military costume” Type A1 Journal article
Year 2013 Publication Journal of analytical atomic spectrometry Abbreviated Journal J Anal Atom Spectrom
Volume 28 Issue (down) 1 Pages 40-51
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Over the past several decades the oeuvre of Rembrandt has been the subject of extensive art historical and scientific investigations. One of the most striking features to emerge is his frequent re-use of canvases and panels. The painting An Old Man in Military Costume (78.PB.246), in the collection of the J. Paul Getty Museum, is an example of such a re-used panel. Conventional imaging techniques revealed the presence of a second portrait under the surface portrait, but the details of this hidden portrait have not yet been revealed. Vermilion (HgS) has been identified to have been used nearly exclusively in the flesh tones of the lower painting, suggesting that element-specific XRF imaging might successfully image the hidden portrait. To test this hypothesis, a full-scale mock-up of the painting was created, including a “free impression” of the hidden portrait, reproducing as closely as possible the pigments and paint stratigraphy of the original painting. XRF imaging of the mock-up painting was conducted using three different XRF imaging systems: a mobile X-ray tube based system and two synchrotron-based setups (one equipped with multiple SDDs and one equipped with a Maia detector). The sensitivity, limits of detection and imaging capabilities of each system under the chosen experimental conditions are evaluated and compared. The results indicate that an investigation of the original painting by this method would have an excellent chance of success.
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Publisher Place of Publication Editor
Language Wos 000314903400003 Publication Date 2012-11-22
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 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. Further, the research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement no 226716. M. Alfeld receives a Ph.D. fellowship of the Research Foundation – Flanders (FWO). The authors gratefully acknowledge Yvonne Szafran and the staff of the Paintings Conservation Department of the J. Paul Getty Museum for making available their infrared reflectography (IRR) and X-radiographic images of the painting, and also the neutron activation analysis (NAA) images acquired in 1996 at NIST by Dr Henry Prask in collaboration with Mark Leonard, former head of the J. Paul Getty Museum Paintings Conservation Department. We are also grateful to Peter Reischig, a graduate intern at the Getty Conservation Institute and a Ph.D. candidate at Delft University of Technology for his assistance. ; Approved Most recent IF: 3.379; 2013 IF: 3.396
Call Number UA @ admin @ c:irua:107704 Serial 5818
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