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Author (up) Amin-Ahmadi, B.; Aashuri, H.
Title Semisolid structure for M2 high speed steel prepared by cooling slope Type A1 Journal article
Year 2010 Publication Journal of materials processing technology Abbreviated Journal J Mater Process Tech
Volume 210 Issue 12 Pages 1632-1635
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Effects of cooling slope angle and the temperature of molten metal on the globular structure of M2 high speed steel after holding at the semisolid state have been investigated. The globular structure was achieved by pouring the molten metal at 1595 °C on the ceramic cooling slope with the length of 200 mm and the angle of 25°. The globular structure of M2 high speed steel in the form of rolledannealed and as cast condition after holding at semisolid state has been achieved. The size of globular grains of cooling slope sample was smaller than that of the rolledannealed and as cast samples. Solid particles of rolledannealed sample after holding at semisolid state had better roundness compared with cooling slope sample. Dissolution of carbides in the austenite phase at grain boundaries leads to formation of globular particles in the semisolid state. MC-type and M6C-type eutectic carbides reprecipitate during cooling cycle along grain boundaries.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000280498200011 Publication Date 2010-06-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0924-0136; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.147 Times cited 12 Open Access
Notes Approved Most recent IF: 3.147; 2010 IF: 1.570
Call Number UA @ lucian @ c:irua:122042 Serial 2983
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Author (up) Amin-Ahmadi, B.; Connétable, D.; Fivel, M.; Tanguy, D.; Delmelle, R.; Turner, S.; Malet, L.; Godet, S.; Pardoen, T.; Proost, J.; Schryvers, D.; Idrissi, H.
Title Dislocation/hydrogen interaction mechanisms in hydrided nanocrystalline palladium films Type A1 Journal article
Year 2016 Publication Acta materialia Abbreviated Journal Acta Mater
Volume 111 Issue 111 Pages 253-261
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The nanoscale plasticity mechanisms activated during hydriding cycles in sputtered nanocrystalline Pd films have been investigated ex-situ using advanced transmission electron microscopy techniques. The internal stress developing within the films during hydriding has been monitored in-situ. Results showed that in Pd films hydrided to β-phase, local plasticity was mainly controlled by dislocation activity in spite of the small grain size. Changes of the grain size distribution and the crystallographic texture have not been observed. In contrast, significant microstructural changes were not observed in Pd films hydrided to α-phase. Moreover, the effect of hydrogen loading on the nature and density of dislocations has been investigated using aberration-corrected TEM. Surprisingly, a high density of shear type stacking faults has been observed after dehydriding, indicating a significant effect of hydrogen on the nucleation energy barriers of Shockley partial dislocations. Ab-initio calculations of the effect of hydrogen on the intrinsic stable and unstable stacking fault energies of palladium confirm the experimental observations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000375812100027 Publication Date 2016-04-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.301 Times cited 14 Open Access
Notes This work was carried out in the framework of the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs, under Contract No. P7/21. The support of the FWO research project G012012N “Understanding nanocrystalline mechanical behaviour from structural investigations” for B. Amin-Ahmadi is also gratefully acknowledged. This work was granted access to the HPC resources of CALMIP (CICT Toulouse, France) under the allocations 2014-p0912 and 2014-p0749. Approved Most recent IF: 5.301
Call Number c:irua:132678 Serial 4054
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Author (up) Amin-Ahmadi, B.; Idrissi, H.; Delmelle, R.; Pardoen, T.; Proost, J.; Schryvers, D.
Title High resolution transmission electron microscopy characterization of fcc -> 9R transformation in nanocrystalline palladium films due to hydriding Type A1 Journal article
Year 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 102 Issue 7 Pages 071911-71914
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Sputtered nanocrystalline palladium thin films with nanoscale growth twins have been subjected to hydriding cycles. The evolution of the twin boundaries has been investigated using high resolution transmission electron microscopy. Surprisingly, the Sigma 3{112} incoherent twin boundaries dissociate after hydriding into two phase boundaries bounding a 9R phase. This phase which corresponds to single stacking faults located every three {111} planes in the fcc Pd structure was not expected because of the high stacking fault energy of Pd. This observation is connected to the influence of the Hydrogen on the stacking fault energy of palladium and the high compressive stresses building up during hydriding. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4793512]
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000315596700023 Publication Date 2013-02-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 14 Open Access
Notes Iap Approved Most recent IF: 3.411; 2013 IF: 3.515
Call Number UA @ lucian @ c:irua:108303 Serial 1462
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Author (up) Amin-Ahmadi, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D.
Title Effect of deposition rate on the microstructure of electron beam evaporated nanocrystalline palladium thin films Type A1 Journal article
Year 2013 Publication Thin solid films : an international journal on the science and technology of thin and thick films Abbreviated Journal Thin Solid Films
Volume 539 Issue Pages 145-150
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The influence of the deposition rate on the formation of growth twins in nanocrystalline Pd films deposited by electron beam evaporation is investigated using transmission electron microscopy. Statistical measurements prove that twin boundary (TB) density and volume fraction of grains containing twins increase with increasing deposition rate. A clear increase of the dislocation density was observed for the highest deposition rate of 5 Å/s, caused by the increase of the internal stress building up during deposition. Based on crystallographic orientation indexation using transmission electron microscopy, it can be concluded that a {111} crystallographic texture increases with increasing deposition rate even though the {101} crystallographic texture remains dominant. Most of the TBs are fully coherent without any residual dislocations. However, for the highest deposition rate (5 Å/s), the coherency of the TBs decreases significantly as a result of the interaction of lattice dislocations emitted during deposition with the growth TBs. The analysis of the grain boundary character of different Pd films shows that an increasing fraction of high angle grain boundaries with misorientation angles around 5565° leads to a higher potential for twin formation.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000321111100025 Publication Date 2013-05-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0040-6090; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.879 Times cited 13 Open Access
Notes Fwo Approved Most recent IF: 1.879; 2013 IF: 1.867
Call Number UA @ lucian @ c:irua:109268 Serial 807
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Author (up) Amini, M.
Title First-principles study of defects in transparent conducting oxide materials Type Doctoral thesis
Year 2014 Publication Abbreviated Journal
Volume Issue Pages
Keywords Doctoral thesis; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Antwerpen Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113390 Serial 1216
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Author (up) Amini, M.N.; Altantzis, T.; Lobato, I.; Grzelczak, M.; Sánchez-Iglesias, A.; Van Aert, S.; Liz-Marzán, L.M.; Partoens, B.; Bals, S.; Neyts, E.C.
Title Understanding the Effect of Iodide Ions on the Morphology of Gold Nanorods Type A1 Journal article
Year 2018 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char
Volume 35 Issue 35 Pages 1800051
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The presence of iodide ions during the growth of gold nanorods strongly affects the shape of the final products, which is proposed to be due to selective iodide adsorption on certain crystallographic facets. Therefore, a detailed structural and morphological characterization of the starting rods is crucial toward understanding this effect. Electron tomography is used to determine the crystallographic indices of the lateral facets of gold nanorods, as well as those present at the tips. Based on this information, density functional theory calculations are used to determine the surface and interface energies of the observed facets and provide insight into the relationship between the amount of iodide ions in the growth solution and the final morphology of anisotropic gold nanoparticles.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000441893400002 Publication Date 2018-06-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0934-0866 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.474 Times cited 6 Open Access OpenAccess
Notes This work was supported by the European Research Council (grant 335078 COLOURATOM to S.B.). T.A., S.V.A. S.B. and E.C.N., acknowledge funding from the Research Foundation Flanders (FWO, Belgium), through project funding (G.0218.14N and G.0369.15N) and a postdoctoral grant to T.A. L.M.L.-M. and M.G. acknowledge funding from the Spanish Ministerio de Economía y Competitividad (grant MAT2013-46101-R). Mozhgan N. Amini and Thomas Altantzis contributed equally to this work. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ecas_sara Approved Most recent IF: 4.474
Call Number EMAT @ emat @c:irua:152998UA @ admin @ c:irua:152998 Serial 5010
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Author (up) Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B.
Title The origin of p-type conductivity in ZnM2O4 (M = Co, Rh, Ir) spinels Type A1 Journal article
Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 16 Issue 6 Pages 2588-2596
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000329926700040 Publication Date 2013-12-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 47 Open Access
Notes Fwo; Goa; Hercules Approved Most recent IF: 4.123; 2014 IF: 4.493
Call Number UA @ lucian @ c:irua:114829 Serial 2525
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Author (up) Amini, M.N.; Leenaerts, O.; Partoens, B.; Lamoen, D.
Title Graphane- and fluorographene-based quantum dots Type A1 Journal article
Year 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 117 Issue 31 Pages 16242-16247
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract With the help of first-principles calculations, we investigate graphane/fluorographene heterostructures with special attention for graphane and fluorographene-based quantum dots. Graphane and fluorographene have large electronic band gaps, and we show that their band structures exhibit a strong type-II alignment. In this way, it is possible to obtain confined electron states in fluorographene nanostructures by embedding them in a graphane crystal. Bound hole states can be created in graphane domains embedded in a fluorographene environment. For circular graphane/fluorographene quantum dots, localized states can be observed in the band gap if the size of the radii is larger than approximately 4 to 5 Å.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000323082300046 Publication Date 2013-07-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 14 Open Access
Notes FWO; GOW; Hercules Approved Most recent IF: 4.536; 2013 IF: 4.835
Call Number UA @ lucian @ c:irua:109457 Serial 1367
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Author (up) Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title Hydrogen impurities and native defects in CdO Type A1 Journal article
Year 2011 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 110 Issue 6 Pages 063521,1-063521,7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract We have used first-principles calculations based on density functional theory to study point defects in CdO within the local density approximation and beyond (LDA+U). Hydrogen interstitials and oxygen vacancies are found to act as shallow donors and can be interpreted as the cause of conductivity in CdO. Hydrogen can also occupy an oxygen vacancy in its substitutional form and also acts as a shallow donor. Similar to what was found for ZnO and MgO, hydrogen creates a multicenter bond with its six oxygen neighbors in CdO. The charge neutrality level for native defects and hydrogen impurities has been calculated. It is shown that in the case of native defects, it is not uniquely defined. Indeed, this level depends highly on the chemical potentials of the species and one can obtain different values for different end states in the experiment. Therefore, a comparison with experiment can only be made if the chemical potentials of the species in the experiment are well defined. However, for the hydrogen interstitial defect, since this level is independent of the chemical potential of hydrogen, one can obtain a unique value for the charge neutrality level. We find that the Fermi level stabilizes at 0.43 eV above the conduction band minimum in the case of the hydrogen interstitial defect, which is in good agreement with the experimentally reported value of 0.4 eV.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000295619300041 Publication Date 2011-09-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 13 Open Access
Notes ; The authors gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project, the FWO-Vlaanderen through Project G.0191.08 and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC. ; Approved Most recent IF: 2.068; 2011 IF: 2.168
Call Number UA @ lucian @ c:irua:93613 Serial 1533
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Author (up) Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title The role of the VZn-NO-H complex in the p-type conductivity in ZnO Type A1 Journal article
Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 17 Issue 17 Pages 5485-5489
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000349616400080 Publication Date 2015-01-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 20 Open Access
Notes FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules Approved Most recent IF: 4.123; 2015 IF: 4.493
Call Number c:irua:123218 Serial 3592
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Author (up) Amiri-Aref, M.
Title Utilization of magnetic nanoparticles and carbon nanotubes to fabrication electrochemical sensors for determination of some important biological and pharmaceutical compounds Type Doctoral thesis
Year 2015 Publication Abbreviated Journal
Volume Issue Pages 137 p.
Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
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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 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:128299 Serial 8727
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Author (up) Amiri-Aref, M.; Raoof, J.B.; Kiekens, F.; De Wael, K.
Title Mixed hemi/ad-micelles coated magnetic nanoparticles for the entrapment of hemoglobin at the surface of a screen-printed carbon electrode and its direct electrochemistry and electrocatalysis Type A1 Journal article
Year 2015 Publication Biosensors and bioelectronics Abbreviated Journal Biosens Bioelectron
Volume 74 Issue Pages 518-525
Keywords A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract An efficient procedure for the physical entrapment of proteins within a biocompatible matrix and their immobilization on electrode surfaces is of utmost importance in the fabrication of biosensors. In this work, the magnetic entrapment of hemoglobin (Hb) at the surface of a screen-printed carbon electrode (SPCE), through mixed hemi/ad-micelles (MHAM) array of positively charged surfactant supported iron oxide magnetic nanoparticles (Mag-NPs), is reported. The Hb/MHAM@Mag-NPs biocomposite is captured at SPCE by a super magnet (Hb/MHAM@Mag-NPs/SPCE). To gain insight in the configuration of the mixed hemi/ad-micelles of CTAB at Mag-NPs, zeta-potential measurements were performed. The entrapment of Hb at MHAM@Mag-NPs was confirmed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR). Direct electron transfer of the Hb intercalated into the composite film showed a pair of well-defined quasi-reversible redox peak at formal potential of −0.255 V vs. Ag/AgCl corresponding to heme Fe(III)/Fe(II) redox couple. It shows that the MHAM@Mag-NPs composite could increase the adsorption ability for Hb, thus provides a facile direct electron transfer between the Hb and the substrate. The proposed biosensor showed excellent electrocatalytic activity to the H2O2 reduction in the wide concentration range from 5.0 to 300.0 µM obtained by amperometric measurement. The MichaelisMenten constant (Km) value of Hb at the modified electrode is 55.4 µM, showing its high affinity. Magnetic entrapment offers a promising design for fast, convenient and effective immobilization of protein within a few minutes for determination of the target molecule in low sample volume at disposable cost-effective SPCE.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000360772800071 Publication Date 2015-07-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0956-5663 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.78 Times cited 14 Open Access
Notes ; We are thankful for the BOF financial support from the University of Antwerp and Hercules financial support (SEM). ; Approved Most recent IF: 7.78; 2015 IF: 6.409
Call Number UA @ admin @ c:irua:126535 Serial 5731
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Author (up) Åmit, Å.; Janssens, K.; Schalm, O.; Kos, M.
Title Spread of façon-de-Venise glassmaking through central and western Europe Type A1 Journal article
Year 2004 Publication Nuclear instruments and methods in physics research B Abbreviated Journal
Volume 213 Issue Pages 717-722
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000187020700143 Publication Date
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 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:45376 Serial 5843
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Author (up) Anaf, W.
Title The influence of particulate matter on cultural heritage : chemical characterisation of the interaction between the atmospheric environment and pigments Type Doctoral thesis
Year 2014 Publication Abbreviated Journal
Volume Issue Pages 319 p.
Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract
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 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:119329 Serial 8095
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Author (up) Anaf, W.; Bencs, L.; Van Grieken, R.; Janssens, K.; De Wael, K.
Title Indoor particulate matter in four Belgian heritage sites : case studies on the deposition of dark-colored and hygroscopic particles Type A1 Journal article
Year 2015 Publication The science of the total environment Abbreviated Journal Sci Total Environ
Volume 506 Issue Pages 361-368
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Atmospheric total suspended particulate (TSP) was passively sampled by means of deployed horizontal and vertical filters in various rooms of four Belgian cultural heritage buildings, installed with various heating/ventilation systems. Soiling/blackening and deposition of inorganic, water-soluble aerosol components were considered. The extent of soiling was determined by means of two independent methods: (1) in terms of the covering rate of the samplers by optical reflection microscopy and (2) the reduction in lightness of the samplers using the CIE L*a*b* color space by spectrophotometry. A fairly good correlation was found between both methods. The inorganic composition of the deposited water-soluble TSP was quantified by means of ion chromatography. Compared to controlled environments, uncontrolled environments showed increased water-soluble aerosol content of the total deposited mass. Higher chloride deposition was observed on horizontal surfaces, compared to vertical surfaces.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000347576800039 Publication Date 2014-11-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.9 Times cited 12 Open Access
Notes ; ; Approved Most recent IF: 4.9; 2015 IF: 4.099
Call Number UA @ admin @ c:irua:120640 Serial 5662
Permanent link to this record
 

 
Author (up) Anaf, W.; Cabal, A.; Robbe, M.; Schalm, O.
Title Real-time wood behaviour : the use of strain gauges for preventive conservation applications Type A1 Journal article
Year 2020 Publication Sensors Abbreviated Journal
Volume 20 Issue 1 Pages 305
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Within the heritage field, the application of strain gauges on wood surfaces is a little-explored but inexpensive and effective method to analyse the environmental appropriateness of rooms for the wooden heritage collections they contain. This contribution proposes a wood sensor connected to a data logger to identify short moments with an elevated risk of harm. Two experiments were performed to obtain insights pertaining to the applicability of wood sensors to evaluate preservation conditions. (1) The representativeness of strain gauges on dummies was tested for their use in evaluating the preservation conditions of a range of wooden objects exposed to the same environment. For this, three situations were mimicked: a bare wood surface, a wood surface covered with a preparation layer, and a wood surface covered with a preparation and varnish layer. (2) The usability of strain gauges to monitor the wood behaviour in real-time measurements was tested with a monitoring campaign of almost two years in a church where a new heating system was installed. The results of both experiments are promising, and the authors encourage a broader application of strain gauges in the heritage field.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000510493100305 Publication Date 2020-01-06
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 Open Access
Notes ; This research was funded by the Belgian Federal Public Planning Service Science Policy (BELSPO) under project number BR/132/A6/AIRCHECQ. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:166595 Serial 6592
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Author (up) Anaf, W.; Horemans, B.; Madeira, T.I.; Carvalho, M.L.; De Wael, K.; Van Grieken, R.
Title Effects of a constructional intervention on airborne and deposited particulate matter in the Portuguese National Tile Museum, Lisbon Type A1 Journal article
Year 2013 Publication Environmental Science and Pollution Research Abbreviated Journal Environ Sci Pollut R
Volume 20 Issue 3 Pages 1849-1857
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In the 1970s, a large ambulatory of the National Tile Museum, Lisbon, was closed with glass panes on both ground and first floor. Although this design was meant to protect the museum collection from ambient air pollutants, small openings between the glass panes remain, creating a semi-enclosed corridor. The effects of the glass panes on the indoor air quality were evaluated in a comparative study by monitoring the airborne particle concentration and the extent of particle deposition at the enclosed corridor as well as inside the museum building. Comparison of the indoor/outdoor ratio of airborne particle concentration demonstrated a high natural ventilation rate in the enclosed corridor as well as inside the museum building. PM10 deposition velocities on vertical surfaces were estimated in the order of 3 × 10−4 m s−1 for both indoor locations. Also, the deposition rates of dark-coloured and black particles in specific were very similar at both indoor locations, causing visual degradation. The effectiveness of the glass panes in protecting the museum collection is discussed.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000315442500061 Publication Date 2012-07-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0944-1344; 1614-7499 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.741 Times cited 15 Open Access
Notes ; ; Approved Most recent IF: 2.741; 2013 IF: 2.757
Call Number UA @ admin @ c:irua:100214 Serial 5583
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Author (up) Anaf, W.; Horemans, B.; Van Grieken, R.; De Wael, K.
Title Chemical boundary conditions for the classification of aerosol particles using computer controlled electron probe microanalysis Type A1 Journal article
Year 2012 Publication Talanta : the international journal of pure and applied analytical chemistry Abbreviated Journal Talanta
Volume 101 Issue Pages 420-427
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract A method for the classification of individual aerosol particles using computer controlled electron probe microanalysis is presented. It is based on chemical boundary conditions (CBC) and enables quick and easy processing of a large set of elemental concentration data (mass%), derived from the X-ray spectra of individual particles. The particles are first classified into five major classes (sea salt related, secondary inorganic, minerals, iron-rich and carbonaceous), after which advanced data mining can be performed by examining the elemental composition of particles within each class into more detail (e.g., by ternary diagrams). The CBC method is validated and evaluated by comparing its results with the output obtained with hierarchical cluster analysis (HCA) for well-known standard particles as well as real aerosol particles collected with a cascade impactor. The CBC method gives reliable results and has a major advantage compared to HCA. CBC is based on boundary conditions that are derived from chemical logical thinking and does not require a translation of a mathematical algorithm output as does HCA. Therefore, the CBC method is more objective and enables comparison between samples without intermediate steps.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000313084400061 Publication Date 2012-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-9140; 1873-3573 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.162 Times cited 3 Open Access
Notes ; ; Approved Most recent IF: 4.162; 2012 IF: 3.498
Call Number UA @ admin @ c:irua:101336 Serial 5511
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Author (up) Anaf, W.; Janssens, K.; De Wael, K.
Title Formation of metallic mercury during photodegradation/photodarkening of \alpha-HgS : electrochemical evidence Type A1 Journal article
Year 2013 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
Volume 52 Issue 48 Pages 12568-12571
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Das rote Pigment α-HgS neigt in Gegenwart von Licht und Chloridionen zur Schwärzung. Als Grund für die Zersetzung und Entfärbung werden die Bildung von (schwarzem) β-HgS oder Quecksilbermetall vermutet, doch diese Substanzen wurden noch nicht auf natürlich oder künstlich zersetzter HgS-Farbe nachgewiesen. Elektrochemische Experimente belegen nun die Bildung von Quecksilbermetall in Gegenwart von Licht und Chloridionen.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000327582900015 Publication Date 2013-10-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.994 Times cited 19 Open Access
Notes ; The authors acknowledge L. Klaassen for valuable discussions and providing samples. We acknowledge financial support from the SDD programme (S2-ART project) of the Belgian Federal Goverment. ; Approved Most recent IF: 11.994; 2013 IF: 11.336
Call Number UA @ admin @ c:irua:111265 Serial 5626
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Author (up) Anaf, W.; Leyva Pernia, D.; Schalm, O.
Title Standardized indoor air quality assessments as a tool to prepare heritage guardians for changing preservation conditions due to climate change Type A1 Journal article
Year 2018 Publication Geosciences Abbreviated Journal
Volume 8 Issue 8 Pages Unsp 276-14
Keywords A1 Journal article; Engineering sciences. Technology; Antwerp Systems and software Modelling (AnSyMo); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Climate change will affect the preservation conditions of our cultural heritage. Therefore, well-considered mitigation actions should be implemented to safeguard our heritage for future generations. Environmental monitoring is essential to follow up the change in preservation conditions and to evaluate the effectiveness of performed mitigation actions. To support heritage guardians in the processing and evaluation of monitored data, an indoor air quality (IAQ) index for heritage applications is introduced. The index is calculated for each measured point in time and is visualized in a user-friendly and intuitive way. The current paper describes the backbone of the IAQ-calculating algorithm. The algorithm is subsequently applied on a case study in which a mitigation action is implemented in a church.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000443254500006 Publication Date 2018-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2076-3263 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:152329 Serial 8578
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Author (up) Anaf, W.; Schalm, O.
Title Climatic quality evaluation by peak analysis and segregation of low-, mid-, and high-frequency fluctuations, applied on a historic chapel Type A1 Journal article
Year 2019 Publication Building and environment Abbreviated Journal
Volume 148 Issue Pages 286-293
Keywords A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Heritage-related guidelines and standards recommend stable climatic conditions, since these contribute to the extension of heritage collections life. As a result, numerous museums and other heritage institutions implement (expensive) mitigation measures to achieve stable conditions. Nevertheless, temperature and relative humidity fluctuations are often still observed. This contribution demonstrates that the analysis of temperature and humidity peaks and drops helps to identify hazards which cause fluctuations in different frequency ranges. This hazard identification provides information on the type of mitigation actions that are required in the near future and in which order they need to be implemented. The approach is illustrated with a case study. A 22 month monitoring campaign was performed in a chapel in the center of Antwerp (Belgium) where the climatic conditions are controlled with a heating, ventilation and air conditioning (HVAC) system. Low-, mid- and high-frequency fluctuations were separated and discussed for their hazards.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000457116500024 Publication Date 2018-11-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0360-1323 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:157569 Serial 7672
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Author (up) Anaf, W.; Schalm, O.; Janssens, K.; De Wael, K.
Title Understanding the (in)stability of semiconductor pigments by a thermodynamic approach Type A1 Journal article
Year 2015 Publication Dyes and pigments Abbreviated Journal Dyes Pigments
Volume 113 Issue Pages 409-415
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Several artists pigments are semiconductors. Some of these materials appear stable over time, whereas others already show remarkable signs of degradation after limited time periods. The (in)stability of these pigments can be understood using a thermodynamic approach. For several pigment-related materials, the thermodynamic oxidation and reduction potential (ϕox and ϕred) were determined and evaluated considering the absolute energy positions of the valence and conduction band edges and the water redox potentials. The positions of ϕox and ϕred can be used in a fast screening of the stability of semiconductor pigments towards photoinduced corrosion in an aqueous/humid environment. This theoretical approach corresponds well with experimental data on pigment permanence and degradation phenomena found in literature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000346543200052 Publication Date 2014-09-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0143-7208 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.473 Times cited 14 Open Access
Notes ; The authors acknowledge the funding from the Belspo S2-ART project (Belgian Federal Government) SD/RI/04A. ; Approved Most recent IF: 3.473; 2015 IF: 3.966
Call Number UA @ admin @ c:irua:118875 Serial 5885
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Author (up) Anaf, W.; Trashin, S.; Schalm, O.; van Dorp, D.; Janssens, K.; De Wael, K.
Title Electrochemical photodegradation study of semiconductor pigments : influence of environmental parameters Type A1 Journal article
Year 2014 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 86 Issue 19 Pages 9742-9748
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract Chemical transformations in paintings often induce discolorations, disturbing the appearance of the image. For an appropriate conservation of such valuable and irreplaceable heritage objects, it is important to have a good know-how on the degradation processes of the (historical) materials: which pigments have been discolored, what are the responsible processes, and which (environmental) conditions have the highest impact on the pigment degradation and should be mitigated. Pigment degradation is already widely studied, either by analyzing historical samples or by accelerated weathering experiments on dummies. However, in historic samples several processes may have taken place, increasing the complexity of the current state, while aging experiments are time-consuming due to the often extended aging period. An alternative method is proposed for a fast monitoring of degradation processes of semiconductor pigments, using an electrochemical setup mimicking the real environment and allowing the identification of harmful environmental parameters for each pigment. Examples are given for the pigments cadmium yellow (CdS) and vermilion (α-HgS).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000343017100058 Publication Date 2014-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 18 Open Access
Notes ; ; Approved Most recent IF: 6.32; 2014 IF: 5.636
Call Number UA @ admin @ c:irua:118834 Serial 5593
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Author (up) Anastasiou, I.; Van Velthoven, N.; Tomarelli, E.; Lombi, A.; Lanari, D.; Liu, P.; Bals, S.; De Vos, D.E.; Vaccaro, L.
Title C2-H arylation of indoles catalyzed by palladium-containing metal-organic-framework in γ-valerolactone Type A1 Journal article
Year 2020 Publication Chemsuschem Abbreviated Journal Chemsuschem
Volume 13 Issue 10 Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract An efficient and selective procedure was developed for the direct C2-H arylation of indoles using a Pd-loaded metal-organic framework (MOF) as a heterogeneous catalyst and the nontoxic biomass-derived solvent gamma-valerolactone (GVL) as a reaction medium. The developed method allows for excellent yields and C-2 selectivity to be achieved and tolerates various substituents on the indole scaffold. The established conditions ensure the stability of the catalyst as well as recoverability, reusability, and low metal leaching into the solution.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000520285700001 Publication Date 2020-02-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1864-5631 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.4 Times cited 22 Open Access Not_Open_Access
Notes ; The research leading to these results has received funding from the NMBP-01-2016 Programme of the European Union's Horizon 2020 Framework Programme H2020/2014-2020/under grant agreement no [720996]. The Universit degli Studi di Perugia and MIUR are acknowledged for financial support to the project AMIS, through the program “Dipartimenti di Eccellenza -2018-2022”. The XAS experiments were performed on beamline BM26A at the European Synchrotron Radiation Facility (ESRF), Grenoble (France). We are grateful to D. Banerjee at the ESRF for providing assistance in using beamline BM26A. Niels Van Velthoven and Dirk E. De Vos also thank FWO for funding. ; Approved Most recent IF: 8.4; 2020 IF: 7.226
Call Number UA @ admin @ c:irua:167678 Serial 6465
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Author (up) Andelkovic, M.; Covaci, L.; Peeters, F.M.
Title DC conductivity of twisted bilayer graphene: Angle-dependent transport properties and effects of disorder Type A1 Journal article
Year 2018 Publication Physical review materials Abbreviated Journal
Volume 2 Issue 3 Pages 034004
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The in-plane dc conductivity of twisted bilayer graphene is calculated using an expansion of the real-space Kubo-Bastin conductivity in terms of Chebyshev polynomials. We investigate within a tight-binding approach the transport properties as a function of rotation angle, applied perpendicular electric field, and vacancy disorder. We find that for high-angle twists, the two layers are effectively decoupled, and the minimum conductivity at the Dirac point corresponds to double the value observed in monolayer graphene. This remains valid even in the presence of vacancies, hinting that chiral symmetry is still preserved. On the contrary, for low twist angles, the conductivity at the Dirac point depends on the twist angle and is not protected in the presence of disorder. Furthermore, for low angles and in the presence of an applied electric field, we find that the chiral boundary states emerging between AB and BA regions contribute to the dc conductivity, despite the appearance of localized states in the AA regions. The results agree qualitatively with recent transport experiments in low-angle twisted bilayer graphene.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000427822700002 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 27 Open Access
Notes ; We acknowledge financial support from the graphene FLAG-ERA project TRANS2DTMD. ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:150838UA @ admin @ c:irua:150838 Serial 4964
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Author (up) Andelkovic, M.; Milovanović, S.P.; Covaci, L.; Peeters, F.M.
Title Double moiré with a twist : supermoiré in encapsulated graphene Type A1 Journal article
Year 2020 Publication Nano Letters Abbreviated Journal Nano Lett
Volume 20 Issue 2 Pages 979
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract A periodic spatial modulation, as created by a moire pattern, has been extensively studied with the view to engineer and tune the properties of graphene. Graphene encapsulated by hexagonal boron nitride (hBN) when slightly misaligned with the top and bottom hBN layers experiences two interfering moire patterns, resulting in a so-called supermoire (SM). This leads to a lattice and electronic spectrum reconstruction. A geometrical construction of the nonrelaxed SM patterns allows us to indicate qualitatively the induced changes in the electronic properties and to locate the SM features in the density of states and in the conductivity. To emphasize the effect of lattice relaxation, we report band gaps at all Dirac-like points in the hole doped part of the reconstructed spectrum, which are expected to be enhanced when including interaction effects. Our result is able to distinguish effects due to lattice relaxation and due to the interfering SM and provides a clear picture on the origin of recently experimentally observed effects in such trilayer heterostuctures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000514255400021 Publication Date 2020-01-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 10.8 Times cited 33 Open Access OpenAccess
Notes ; This work was funded by FLAGERA project TRANS2DTMD and the Flemish Science Foundation (FWO-Vl) through a postdoc fellowship for S.P.M. The authors acknowledge useful discussions with W. Zihao and K. Novoselov. ; Approved Most recent IF: 10.8; 2020 IF: 12.712
Call Number UA @ admin @ c:irua:168685 Serial 6490
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Author (up) Andelkovic, M.; Rakhimov, K.Y.; Chaves, A.; Berdiyorov, G.R.; Milošević, M.V.
Title Wave-packet propagation in a graphene geometric diode Type A1 Journal article
Year 2023 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal
Volume 147 Issue Pages 115607-4
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Dynamics of electron wave-packets is studied using the continuum Dirac model in a graphene geometric diode where the propagation of the wave packet is favored in certain direction due to the presence of geometric constraints. Clear rectification is obtained in the THz frequency range with the maximum rectification level of 3.25, which is in good agreement with recent experiments on graphene ballistic diodes. The rectification levels are considerably higher for systems with narrower channels. In this case, the wave packet transmission probabilities and rectification rate also strongly depend on the energy of the incident wave packet, as a result of the quantum nature of energy levels along such channels. These findings can be useful for fundamental understanding of the charge carrier dynamics in graphene geometry diodes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000903737000003 Publication Date 2022-12-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.3 Times cited 1 Open Access OpenAccess
Notes Approved Most recent IF: 3.3; 2023 IF: 2.221
Call Number UA @ admin @ c:irua:193497 Serial 7351
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Author (up) Andersen, J.A.; Christensen, J.M.; Østberg, M.; Bogaerts, A.; Jensen, A.D.
Title Plasma-catalytic ammonia decomposition using a packed-bed dielectric barrier discharge reactor Type A1 Journal article
Year 2022 Publication International Journal Of Hydrogen Energy Abbreviated Journal Int J Hydrogen Energ
Volume 47 Issue 75 Pages 32081-32091
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma-catalytic ammonia decomposition as a method for producing hydrogen was studied in a packed-bed dielectric barrier discharge (DBD) reactor at ambient pressure and a fixed plasma power. The influence of packing the plasma zone with various dielectric materials, typically used as catalyst supports, was examined. At conditions (21 W, 75 Nml/min NH3) where an NH3 conversion of 5% was achieved with plasma alone, an improved decomposition was found when introducing dielectric materials with dielectric constants between 4 and 30. Of the tested materials, MgAl2O4 yielded the highest conversion (15.1%). The particle size (0.3-1.4 mm) of the MgAl2O4 packing was found to have a modest influence on the conversion, which dropped from 15.1% to 12.6% with increasing particle size. Impregnation of MgAl2O4 with different metals was found to decrease the NH3 conversion, with the Ni impregnation still showing an improved conversion (7%) compared to plasma-only. The plasma-assisted ammonia decomposition occurs in the gas phase due to micro-discharges, as evident from a linear correlation between the conversion and the frequency of micro-discharges for both plasma alone and with the various solid packing materials. The primary function of the solid is thus to facilitate the gas phase reaction by assisting the creation of micro-discharges. Lastly, insulation of the reactor to raise the temperature to 230 degrees C in the plasma zone was found to have a negative effect on the conversion, as a change from volume discharges to surface discharges occurred. The study shows that NH3 can be decomposed to provide hydrogen by exposure to a non-thermal plasma, but further developments are needed for it to become an energy efficient technology. (C)2022 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000865421200012 Publication Date 2022-08-17
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 7.2 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 7.2
Call Number UA @ admin @ c:irua:191512 Serial 7191
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Author (up) Andersen, Ja.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad.
Title Plasma-catalytic dry reforming of methane: Screening of catalytic materials in a coaxial packed-bed DBD reactor Type A1 Journal article
Year 2020 Publication Chemical Engineering Journal Abbreviated Journal Chem Eng J
Volume 397 Issue Pages 125519
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The combination of catalysis with non-thermal plasma is a promising alternative to thermal catalysis. A dielectric-barrier discharge reactor was used to study plasma-catalytic dry reforming of methane at ambient pressure and temperature and a fixed plasma power of 45 W. The effect of different catalytic packing materials was evaluated in terms of conversion, product selectivity, and energy efficiency. The conversion of CO2 (~22%) and CH4 (~33%) were found to be similar in plasma-only and when introducing packing materials in plasma. The main reason is the shorter residence time of the gas due to packing geometry, when compared at identical flow rates. H2, CO, C2-C4 hydrocarbons, and oxygenates were identified in the product gas. High selectivity towards H2 and CO were found for all catalysts and plasma-only, with a H2/CO molar ratio of ~0.9. The lowest syngas selectivity was obtained with Cu/Al2O3 (~66%), which instead, had the highest alcohol selectivity (~3.6%).
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000542296100011 Publication Date 2020-05-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 15.1 Times cited Open Access
Notes Department of Chemical and Biochemical Engineering, Technical University of Denmark; We thank Haldor Topsoe A/S for providing all the catalytic materials used and the Department of Chemical and Biochemical Engineering, Technical University of Denmark, for funding this project. Approved Most recent IF: 15.1; 2020 IF: 6.216
Call Number PLASMANT @ plasmant @c:irua:170613 Serial 6406
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Author (up) Andersen, Ja.; Holm, Mc.; van 't Veer, K.; Christensen, Jm.; Østberg, M.; Bogaerts, A.; Jensen, Ad.
Title Plasma-catalytic ammonia synthesis in a dielectric barrier discharge reactor: A combined experimental study and kinetic modeling Type A1 Journal Article
Year 2023 Publication Chemical engineering journal Abbreviated Journal
Volume 457 Issue Pages 141294
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma-catalytic ammonia synthesis in a dielectric barrier discharge reactor has emerged as a possible route for electrification of nitrogen fixation. In this study, we use a combination of experiments and a plasma kinetic model to investigate the ammonia synthesis from N2 and H2, both with and without a solid packing material in the plasma zone. The effect of plasma power, feed flow rate, N2:H2 feed ratio, gas residence time, temperature, and packing material (MgAl2O4 alone or impregnated with Co or Ru) on the ammonia synthesis rate were examined in the experiments. The kinetic model was employed to improve our understanding of the ammonia formation pathways and identify possible changes in these pathways when altering the N2:H2 feed ratio. A higher NH3 synthesis rate was achieved when increasing the feed flow rate, as well as when increasing the gas tem-perature from 100 to 200 ◦C when a packing material was present in the plasma. At the elevated temperature of 200 ◦C, an optimum in the NH3 synthesis rate was observed at an equimolar feed ratio (N2:H2 =1:1) for the plasma alone and MgAl2O4, while a N2-rich feed was favored for Ru/MgAl2O4 and Co/MgAl2O4. The optimum in the synthesis rate with the N2-rich feed, where high energy electrons are more likely to collide with N2, suggests that the rate-limiting step is the dissociation of N2 in the gas phase. This is supported by the kinetic model when packing material was used. However, for the plasma alone, the model found that the N2 dissociation is only rate limiting in H2-rich feeds, whereas the limited access to H in N2-rich feeds makes the hydrogenation of N species limiting.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001058978000001 Publication Date 2023-01-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-8947 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 15.1 Times cited Open Access OpenAccess
Notes We thank Topsoe A/S for providing the catalytic materials used in the study, the research group PLASMANT (University of Antwerp) for sharing their plasma kinetic model and allocating time on their cluster for the calculations, and the Department of Chemical and Biochemical Engineering (Technical University of Denmark) for funding the project. Approved Most recent IF: 15.1; 2023 IF: 6.216
Call Number PLASMANT @ plasmant @c:irua:195877 Serial 7234
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