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Author Hoffman, B.M.; Lukoyanov, D.; Yang, Z.-Y.; Dean, D.R.; Seefeldt, L.C.
  Title Mechanism of Nitrogen Fixation by Nitrogenase: The Next Stage Type A1 Journal Article
  Year (down) 2014 Publication Chemical Reviews Abbreviated Journal Chem. Rev.
  Volume 114 Issue 8 Pages 4041-4062
  Keywords A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
  Abstract Ammonia is a crucial nutrient used for plant growth and as a building block in pharmaceutical and chemical industry, produced via nitrogen fixation of the ubiquitous atmospheric N2. Current industrial ammonia production relies heavily on fossil resources, but a lot of work is put into developing non-fossil based pathways. Among these is the use of nonequilibrium plasma. In this work, we investigated water vapor as H source for nitrogen fixation into NH3 by non-equilibrium plasma. The highest selectivity towards NH3 was observed with low amounts of added H2O vapor, but the highest production rate was reached at high H2O vapor.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos Publication Date 2014-04-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0009-2665 ISBN Additional Links
  Impact Factor Times cited Open Access
  Notes We would like to thank Sylvia Dewilde (Department of Biomedical Sciences) for providing analytical equipment. Approved no
  Call Number PLASMANT @ plasmant @ Serial 6337
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Author Godoi, R.H.M.; Lima Bittencourt, A.V.; Hirata, P.Y.; Jafelicci Junior, M.; dos Reis Neto, J.M.; Van Grieken, R.
  Title Characterization of the ionic and particulate systems in the reservoir Type H2 Book chapter
  Year (down) 2014 Publication Abbreviated Journal
  Volume Issue Pages 143-159 T2 - Reservoir eutrophication : preventive
  Keywords H2 Book chapter; 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 9781780406473 Additional Links UA library record
  Impact Factor Times cited Open Access
  Notes Approved no
  Call Number UA @ admin @ c:irua:119046 Serial 7634
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Author Velimirovic, M.; Carniato, L.; Simons, Q.; Schoups, G.; Seuntjens, P.; Bastiaens, L.
  Title Corrosion rate estimations of microscale zerovalent iron particles via direct hydrogen production measurements Type A1 Journal article
  Year (down) 2014 Publication Journal of hazardous materials Abbreviated Journal
  Volume 270 Issue Pages 18-26
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
  Abstract In this study, the aging behavior of microscale zerovalent iron (mZVI) particles was investigated by quantifying the hydrogen gas generated by anaerobic mZVI corrosion in batch degradation experiments. Granular iron and nanoscale zerovalent iron (nZVI) particles were included in this study as controls. Firstly, experiments in liquid medium (without aquifer material) were performed and revealed that mZV1 particles have approximately a 10-30 times lower corrosion rate than nZVI particles. A good correlation was found between surface area normalized corrosion rate (R-SA) and reaction rate constants (K-SA) of PCE, TCE, cDCE and 1,1,1-TCA. Generally, particles with higher degradation rates also have faster corrosion rates, but exceptions do exists. In a second phase, the hydrogen evolution was also monitored during batch tests in the presence of aquifer material and real groundwater. A 4-9 times higher corrosion rate of mZV1 particles was observed under the natural environment in comparison with the aquifer free artificial condition, which can be attributed to the low pH of the aquifer and its buffer capacity. A corrosion model was calibrated on the batch experiments to take into account the inhibitory effects of the corrosion products (dissolved iron, hydrogen and OH-) on the iron corrosion rate. (C) 2014 Elsevier B.V. All rights reserved.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000335109200003 Publication Date 2014-02-01
  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 Times cited Open Access
  Notes Approved no
  Call Number UA @ admin @ c:irua:117179 Serial 7738
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Author Abreu, Y.; Cruz, C.M.; Pinera, I.; Leyva, A.; Cabal, A.E.; van Espen, P.
  Title DFT study of the hyperfine parameters and magnetic properties of ZnO doped with 57Fe Type A1 Journal article
  Year (down) 2014 Publication Solid state communications Abbreviated Journal
  Volume 185 Issue Pages 25-29
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Magnetic state of Fe-57 implanted and doped ZnO samples have been reported and studied by Mossbauer spectroscopy at different temperatures. The Mossbauer spectra mainly showed four doublets and three sextets, but some ambiguous identification remains regarding the probe site location and influence of defects in the hyperfine and magnetic parameters. In the present work some possible implantation configurations are suggested and evaluated using Monte Carlo simulation and electronic structure calculations within the density functional theory. Various implantation environments were proposed and studied considering the presence of defects. The obtained Fe-57 hyperfine parameters show a good agreement with the reported experimental values for some of these configurations. The possibility of Fe pair formation, as well as a Zn site vacancy stabilization between he second and third neighborhood of the implantation site, is supported. (C) 2014 Elsevier Ltd. All rights reserved.
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  Corporate Author Thesis
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  Language Wos 000333751400007 Publication Date 2014-01-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0038-1098 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:116839 Serial 7806
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Author Janssens, K.; Alfeld, M.; Van der Snickt, G.; De Nolf, W.; Vanmeert, F.; Monico, L.; Legrand, S.; Dik, J.; Cotte, M.; Falkenberg, G.; van der Loeff, L.; Leeuwestein, M.; Hendriks, E.
  Title Examination of Vincent van Gogh's paintings and pigments by means of state-of-the-art analytical methods Type H2 Book chapter
  Year (down) 2014 Publication Abbreviated Journal
  Volume Issue Pages 373-403 T2 - Science and art : the painted surface
  Keywords H2 Book chapter; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Recent studies in which X-ray beams of macroscopic to (sub) microscopic dimensions were used for non-destructive analysis and characterization of pigments, paint micro samples and/or entire paintings by Vincent van Gogh are concisely reviewed. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Microscopic and macroscopic XRF are variants of the method that are well suited to visualize the elemental distribution of key elements, mostly metals, present in paint multi layers, either on the length scale from 1–100 μm inside micro samples taken from paintings or on the 1–100 cm length scale when the (subsurface) distribution of specific pigments in entire paintings is concerned. In the context of the characterization of van Gogh's pigments subject to natural degradation, the use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS and μ-XRD have proven themselves to be very suitable for such studies. Their use is often combined with microscopic Fourier transform infra-red (μ-FTIR) spectroscopy since this method delivers complementary information at more or less the same length scale as the X-ray microprobe techniques. Also in the context of macroscopic imaging of works of art, the complementary use of X-ray based and infra-red based imaging appears very promising; some recent developments are discussed.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos Publication Date 2020-02-24
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN 978-1-84973-818-7 Additional Links UA library record
  Impact Factor Times cited Open Access
  Notes Approved no
  Call Number UA @ admin @ c:irua:190782 Serial 7943
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Author Dekov, V.M.; Vanlierde, E.; Billström, K.; Gatto Rotondo, G.; van Meel, K.; Darchuk, L.; Van Grieken, R.; et al.
  Title Ferrihydrite precipitation in groundwater-fed river systems (Nete and Demer river basins, Belgium) : insights from a combined Fe-Zn-Sr-Nd-Pb-isotope study Type A1 Journal article
  Year (down) 2014 Publication Chemical geology Abbreviated Journal
  Volume 386 Issue Pages 1-15
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Two groundwater-fed river systems (Nete and Demer, Belgium) carry red suspended material that settles on the river bed forming red sediments. The local aquifer that feeds these river systems is a glauconite-rich sand, which provides most of the dissolved Fe to the rivers. The solid component of these systems, i.e., the red suspended material and sediments, has a simple mineralogy (predominantly ferrihydrite), but shows a complex geochemistry pointing out the different processes contributing to the river chemistry: (1) the red sediments have higher transition metal (excluding Cu) and detrital element (e.g., Si, Al, K, Rb, etc.) concentrations than the red suspended matter because of their longer residence time in the river and higher contribution of the background (aquifer) component, respectively; (2) the red suspended material and sediments have inherited their rare earth element (REE) patterns from the aquifer; (3) the origin of Sr present in the red suspended matter and red sediments is predominantly marine (i.e., Quaternary calcareous rocks), but a small amount is geogenic (i.e., from detrital rocks); (4) Pb in both solids originates mostly from anthropogenic and geogenic sources; (5) all of the anthropogenic Pb in the red suspended material and sediments is hosted by the ferrihydrite; (6) Nd budget of the red riverine samples is controlled by the geogenic source and shows little anthropogenic component; (7) the significant Fe- and Zn-isotope fractionations are in line with the previous studies. Their fractionation patterns do not correlate, suggesting that the processes controlling the isotope geochemistry of Fe and Zn are different: oxidation/reduction most likely governs the Fe-isotope fractionation, whereas adsorption/desorption or admixing of anthropogenic sources controls the isotope fractionation of Zn.
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  Language Wos 000345441000001 Publication Date 2014-08-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0009-2541 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:118323 Serial 7962
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Author Abreu, Y.; Cruz, C.M.; Pinera, I.; Leyva, A.; Cabal, A.E.; van Espen, P.; Van Remortel, N.
  Title Hyperfine electric parameters calculation in Si samples implanted with 57Mn\rightarrow57Fe Type A1 Journal article
  Year (down) 2014 Publication Physica: B : condensed matter Abbreviated Journal
  Volume 445 Issue Pages 1-4
  Keywords A1 Journal article; Particle Physics Group; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Nowadays the electronic structure calculations allow the study of complex systems determining the hyperfine parameters measured at a probe atom, including the presence of crystalline defects. The hyperfine electric parameters have been measured by Mossbauer spectroscopy in silicon materials implanted with Mn-57 ->,Fe-57 ions, observing four main contributions to the spectra. Nevertheless, some ambiguities still remain in the Fe-57 Mossbauer spectra interpretation in this case, regarding the damage configurations and its evolution with annealing. In the present work several implantation environments are evaluated and the Fe-57 hyperfine parameters are calculated. The observed correlation among the studied local environments and the experimental observations is presented, and a tentative microscopic description of the behavior and thermal evolution of the characteristic defects local environments of the probe atoms concerning the location of vacancies and interstitial Si in the neighborhood of Fe-57 ions in substitutional and interstitial sites is proposed. (C) 2014 Elsevier B.V. All rights reserved
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000336478700001 Publication Date 2014-03-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0921-4526; 1873-2135 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:117697 Serial 8046
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Author Pinera, I.; Cruz, C.M.; Leyva, A.; Abreu, Y.; Cabal, A.E.; van Espen, P.; Van Remortel, N.
  Title Improved calculation of displacements per atom cross section in solids by gamma and electron irradiation Type A1 Journal article
  Year (down) 2014 Publication Interactions With Materials And Atoms Abbreviated Journal
  Volume 339 Issue Pages 1-7
  Keywords A1 Journal article; Engineering sciences. Technology; Particle Physics Group; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Several authors had estimated the displacements per atom cross sections under different approximations and models, including most of the main gamma- and electron-material interaction processes. These previous works used numerical approximation formulas which are applicable for limited energy ranges. We proposed the Monte Carlo assisted Classical Method (MCCM), which relates the established theories about atom displacements to the electron and positron secondary fluence distributions calculated from the Monte Carlo simulation. In this study the MCCM procedure is adapted in order to estimate the displacements per atom cross sections for gamma and electron irradiation. The results obtained through this procedure are compared with previous theoretical calculations. An improvement in about 10-90% for the gamma irradiation induced dpa cross section is observed in our results on regard to the previous evaluations for the studied incident energies. On the other hand, the dpa cross section values produced by irradiation with electrons are improved by our calculations in about 5-50% when compared with the theoretical approximations. When thin samples are irradiated with electrons, more precise results are obtained through the MCCM (in about 20-70%) with respect to the previous studies. (C) 2014 Elsevier B.V. All rights reserved.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000343785500001 Publication Date 2014-09-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0168-583x 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:121161 Serial 8069
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Author Dirtu, A.C.; Buczyńska, A.J.; Godoi, A.F.L.; Favoreto, R.; Bencs, L.; Potgieter-Vermaak, S.S.; Godoi, R.H.M.; Van Grieken, R.; Van Vaeck, L.
  Title Methods, fluxes and sources of gas phase alkyl nitrates in the coastal air Type A1 Journal article
  Year (down) 2014 Publication Environmental monitoring and assessment Abbreviated Journal
  Volume 186 Issue 10 Pages 6445-6457
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre
  Abstract The daily and seasonal atmospheric concentrations, deposition fluxes and emission sources of a few C3C9 gaseous alkyl nitrates (ANs) at the Belgian coast (De Haan) on the Southern North Sea were determined. An adapted sampler design for low- and high-volume air-sampling, optimized sample extraction and clean-up, as well as identification and quantification of ANs in air samples by means of gas chromatography mass spectrometry, are reported. The total concentrations of ANs ranged from 0.03 to 85 pptv and consisted primarily of the nitro-butane and nitro-pentane isomers. Air mass backward trajectories were calculated by the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to determine the influence of main air masses on AN levels in the air. The shorter chain ANs have been the most abundant in the Atlantic/Channel/UK air masses, while longer chain ANs prevailed in continental air. The overall mean N fluxes of the ANs were slightly higher for summer than those for winter-spring, although their contributions to the total nitrogen flux were low. High correlations between AN and HNO2 levels were observed during winter/spring. During summer, the shorter chain ANs correlated well with precipitation. Source apportionment by means of principal component analysis indicated that most of the gas phase ANs could be attributed to traffic/combustion, secondary photochemical formation and biomass burning, although marine sources may also have been present and a contributing factor.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000341497800035 Publication Date 2014-06-21
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1420-2026; 1573-2967 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:118906 Serial 8224
Permanent link to this record
 

 
Author Arana, A.; Loureiro, A.L.; Barbosa, H.M.J.; Van Grieken, R.; Artaxo, P.
  Title Optimized energy dispersive X-ray fluorescence analysis of atmospheric aerosols collected at pristine and perturbed Amazon Basin sites Type A1 Journal article
  Year (down) 2014 Publication X-ray spectrometry Abbreviated Journal
  Volume 43 Issue 4 Pages 228-237
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract Elemental composition of aerosols is important to source apportionment studies and to understand atmospheric processes that influence aerosol composition. Energy dispersive X-ray fluorescence spectroscopy was applied for measuring the elemental composition of Amazonian atmospheric aerosols. The instrument used was a spectrometer Epsilon 5, PANalytical B. V., with tridimensional geometry that reduces the background signal with a polarized X-ray detection. The measurement conditions were optimized for low-Z elements, e. g. Mg, Al, Si, that are present at very low concentrations in the Amazon. From Na to K, our detection limits are about 50% to 75% lower than previously published results for similar instrument. Calibration was performed using Micromatter standards, except for P whose standard was produced by nebulization of an aqueous solution of KH2PO4 at our laboratory. The multi-element reference material National Institute of Standards and Technology-2783 (air particulate filter) was used for evaluating the accuracy of the calibration procedure of the 22 elements in our standard analysis routine, and the uncertainty associated with calibration procedures was evaluated. The overall performance of the instrument and validation of our measurements were assessed by comparison with results obtained from parallel analysis using particle-induced X-ray emission and another Epsilon 5 spectrometer. The elemental composition in 660 samples collected at a pristine site in the Amazon Basin and of 1416 samples collected at a site perturbed by land use change was determined. Our measurements show trace elements associated with biogenic aerosols, soil dust, biomass burning, and sea-salt, even for the very low concentrations as observed in Amazonia. Copyright (C) 2014 John Wiley & Sons, Ltd.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000337724600006 Publication Date 2014-06-09
  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 Times cited Open Access
  Notes Approved no
  Call Number UA @ admin @ c:irua:118419 Serial 8342
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Author Van de Voorde, L.; Vandevijvere, M.; Vekemans, B.; Van Pevenage, J.; Caen, J.; Vandenabeele, P.; van Espen, P.; Vincze, L.
  Title Study of a unique 16th century Antwerp majolica floor in the Rameyenhof castle's chapel by means of X-ray fluorescence and portable Raman analytical instrumentation Type A1 Journal article
  Year (down) 2014 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal
  Volume 102 Issue Pages 28-35
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
  Abstract The most unique and only known 16th century Antwerp majolica tile floor in Belgium is situated in a tower of the Rameyenhof castle (Gestel, Belgium). This exceptional work of art has recently been investigated in situ by using X-ray fluorescence (XRF) and Raman spectroscopy in order to study the material characteristics. This study reports on the result of the analyses based on the novel combination of non-destructive and portable instrumentation, including a handheld XRF spectrometer for obtaining elemental information and a mobile Raman spectrometer for retrieving structural and molecular information on the floor tiles in the Rameyenhof castle and on a second, similar medallion, which is stored in the Rubens House museum in Antwerp (Belgium). The investigated material, majolica, is a type of ceramic, which fascinated many people and potters throughout history by its beauty and colourful appearance. In this study the characteristic major/minor and trace element signature of 16th century Antwerp majolica is determined and the pigments used for the colourful paintings present on the floor are identified. Furthermore, based on the elemental fingerprint of the white glaze, and in particular on the presence of zinc in the tiles – an element that was not used for making 16th century majolica – valuable information about the originality of the chapel floor and the two central medallions is acquired. (C) 2014 Elsevier B.V. All rights reserved.
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  Publisher Place of Publication Editor
  Language Wos 000347604100005 Publication Date 2014-10-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0584-8547; 1873-3565 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:123850 Serial 8592
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Author Čukarić, N.A.; Tadić, M.Z.; Partoens, B.; Peeters, F.M.
  Title 30-band k\cdot p model of electron and hole states in silicon quantum wells Type A1 Journal article
  Year (down) 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 88 Issue 20 Pages 205306
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We modeled the electron and hole states in Si/SiO2 quantum wells within a basis of standing waves using the 30-band k . p theory. The hard-wall confinement potential is assumed, and the influence of the peculiar band structure of bulk silicon on the quantum-well sub-bands is explored. Numerous spurious solutions in the conduction-band and valence-band energy spectra are found and are identified to be of two types: (1) spurious states which have large contributions of the bulk solutions with large wave vectors (the high-k spurious solutions) and (2) states which originate mainly from the spurious valley outside the Brillouin zone (the extravalley spurious solutions). An algorithm to remove all those nonphysical solutions from the electron and hole energy spectra is proposed. Furthermore, slow and oscillatory convergence of the hole energy levels with the number of basis functions is found and is explained by the peculiar band mixing and the confinement in the considered quantum well. We discovered that assuming the hard-wall potential leads to numerical instability of the hole states computation. Nonetheless, allowing the envelope functions to exponentially decay in a barrier of finite height is found to improve the accuracy of the computed hole states.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000327161500007 Publication Date 2013-11-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 10 Open Access
  Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Belgian Science Policy (IAP), the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:112704 Serial 18
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Author Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M.
  Title Adsorption and absorption of boron, nitrogen, aluminum, and phosphorus on silicene : stability and electronic and phonon properties Type A1 Journal article
  Year (down) 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085444-85448
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Ab initio calculations within the density-functional theory formalism are performed to investigate the chemical functionalization of a graphene-like monolayer of siliconsilicenewith B, N, Al, or P atoms. The structural, electronic, magnetic, and vibrational properties are reported. The most preferable adsorption sites are found to be valley, bridge, valley and hill sites for B, N, Al, and P adatoms, respectively. All the relaxed systems with adsorbed/substituted atoms exhibit metallic behavior with strongly bonded B, N, Al, and P atoms accompanied by an appreciable electron transfer from silicene to the B, N, and P adatom/substituent. The Al atoms exhibit opposite charge transfer, with n-type doping of silicene and weaker bonding. The adatoms/substituents induce characteristic branches in the phonon spectrum of silicene, which can be probed by Raman measurements. Using molecular dynamics, we found that the systems under study are stable up to at least T=500 K. Our results demonstrate that silicene has a very reactive and functionalizable surface.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315482900007 Publication Date 2013-02-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 169 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107071 Serial 60
Permanent link to this record
 

 
Author Sahin, H.; Peeters, F.M.
  Title Adsorption of alkali, alkaline-earth, and 3d transition metal atoms on silicene Type A1 Journal article
  Year (down) 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085423-85429
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The adsorption characteristics of alkali, alkaline-earth, and transition metal adatoms on silicene, a graphene-like monolayer structure of silicon are analyzed by means of first-principles calculations. In contrast to graphene, interaction between the metal atoms and the silicene surface is quite strong due to its highly reactive buckled hexagonal structure. In addition to structural properties, we also calculate the electronic band dispersion, net magnetic moment, charge transfer, work function, and dipole moment of the metal adsorbed silicene sheets. Alkali metals, Li, Na, and K, adsorb to hollow sites without any lattice distortion. As a consequence of the significant charge transfer from alkalis to silicene, metalization of silicene takes place. Trends directly related to atomic size, adsorption height, work function, and dipole moment of the silicene/alkali adatom system are also revealed. We found that the adsorption of alkaline-earth metals on silicene is entirely different from their adsorption on graphene. The adsorption of Be, Mg, and Ca turns silicene into a narrow gap semiconductor. Adsorption characteristics of eight transition metals Ti, V, Cr, Mn, Fe, Co, Mo, and W are also investigated. As a result of their partially occupied d orbital, transition metals show diverse structural, electronic, and magnetic properties. Upon the adsorption of transition metals, depending on the adatom type and atomic radius, the system can exhibit metal, half-metal, and semiconducting behavior. For all metal adsorbates, the direction of the charge transfer is from adsorbate to silicene, because of its high surface reactivity. Our results indicate that the reactive crystal structure of silicene provides a rich playground for functionalization at nanoscale. DOI: 10.1103/PhysRevB.87.085423
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315146500008 Publication Date 2013-02-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 281 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWO Pegasus Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107663 Serial 62
Permanent link to this record
 

 
Author Houssa, M.; van den Broek, B.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
  Title An electric field tunable energy band gap at silicene/(0001) ZnS interfaces Type A1 Journal article
  Year (down) 2013 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 15 Issue 11 Pages 3702-3705
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract The interaction of silicene, the silicon counterpart of graphene, with (0001) ZnS surfaces is investigated theoretically, using first-principles simulations. The charge transfer occurring at the silicene/(0001) ZnS interface leads to the opening of an indirect energy band gap of about 0.7 eV in silicene. Remarkably, the nature (indirect or direct) and magnitude of the energy band gap of silicene can be controlled by an external electric field: the energy gap is predicted to become direct for electric fields larger than about 0.5 V angstrom(-1), and the direct energy gap decreases approximately linearly with the applied electric field. The predicted electric field tunable energy band gap of the silicene/(0001) ZnS interface is very promising for its potential use in nanoelectronic devices.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000315165100002 Publication Date 2013-01-29
  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 74 Open Access
  Notes Approved Most recent IF: 4.123; 2013 IF: 4.198
  Call Number UA @ lucian @ c:irua:107702 Serial 94
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Author Li, D.Y.; Zeng, Y.J.; Pereira, L.M.C.; Batuk, D.; Hadermann, J.; Zhang, Y.Z.; Ye, Z.Z.; Temst, K.; Vantomme, A.; Van Bael, M.J.; Van Haesendonck, C.;
  Title Anisotropic magnetism and spin-dependent transport in Co nanoparticle embedded ZnO thin films Type A1 Journal article
  Year (down) 2013 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 114 Issue 3 Pages 033909-6
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Oriented Co nanoparticles were obtained by Co ion implantation in crystalline ZnO thin films grown by pulsed laser deposition. Transmission electron microscopy revealed the presence of elliptically shaped Co precipitates with nanometer size, which are embedded in the ZnO thin films, resulting in anisotropic magnetic behavior. The low-temperature resistance of the Co-implanted ZnO thin films follows the Efros-Shklovskii type variable-range-hopping. Large negative magnetoresistance (MR) exceeding 10% is observed in a magnetic field of 1 T at 2.5K and the negative MR survives up to 250K (0.3%). The negative MR reveals hysteresis as well as anisotropy that correlate well with the magnetic properties, clearly demonstrating the presence of spin-dependent transport. (C) 2013 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000322202700071 Publication Date 2013-07-17
  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 10 Open Access
  Notes Approved Most recent IF: 2.068; 2013 IF: 2.185
  Call Number UA @ lucian @ c:irua:110765 Serial 126
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Author Sahin, H.; Tongay, S.; Horzum, S.; Fan, W.; Zhou, J.; Li, J.; Wu, J.; Peeters, F.M.
  Title Anomalous Raman spectra and thickness-dependent electronic properties of WSe2 Type A1 Journal article
  Year (down) 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 16 Pages 165409-6
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Typical Raman spectra of transition-metal dichalcogenides (TMDs) display two prominent peaks, E-2g and A(1g), that are well separated from each other. We find that these modes are degenerate in bulk WSe2 yielding one single Raman peak in contrast to other TMDs. As the dimensionality is lowered, the observed peak splits in two. In contrast, our ab initio calculations predict that the degeneracy is retained even for WSe2 monolayers. Interestingly, for minuscule biaxial strain, the degeneracy is preserved, but once the crystal symmetry is broken by a small uniaxial strain, the degeneracy is lifted. Our calculated phonon dispersion for uniaxially strained WSe2 shows a good match to the measured Raman spectrum, which suggests that uniaxial strain exists in WSe2 flakes, possibly induced during the sample preparation and/or as a result of the interaction between WSe2 and the substrate. Furthermore, we find that WSe2 undergoes an indirect-to-direct band-gap transition from bulk to monolayers, which is ubiquitous for semiconducting TMDs. These results not only allow us to understand the vibrational and electronic properties of WSe2, but also point to effects of the interaction between the monolayer TMDs and the substrate on the vibrational and electronic properties. DOI: 10.1103/PhysRevB.87.165409
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000317195400007 Publication Date 2013-04-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 365 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem programme of the Flemish government. Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H. S. is supported by the FWO Pegasus Marie Curie Long Fellowship program. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:108471 Serial 134
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Author Grujić, M.; Tadić, M.; Peeters, F.M.
  Title Antiferromagnetism in hexagonal graphene structures : rings versus dots Type A1 Journal article
  Year (down) 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 87 Issue 8 Pages 085434-85436
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Themean-field Hubbard model is used to investigate the formation of the antiferromagnetic phase in hexagonal graphene rings with inner zigzag edges. The outer edge of the ring was taken to be either zigzag or armchair, and we found that both types of structures can have a larger antiferromagnetic interaction as compared with hexagonal dots. This difference could be partially ascribed to the larger number of zigzag edges per unit area in rings than in dots. Furthermore, edge states localized on the inner ring edge are found to hybridize differently than the edge states of dots, which results in important differences in the magnetism of graphene rings and dots. The largest staggered magnetization is found when the outer edge has a zigzag shape. However, narrow rings with armchair outer edge are found to have larger staggered magnetization than zigzag hexagons. The edge defects are shown to have the least effect on magnetization when the outer ring edge is armchair shaped. DOI: 10.1103/PhysRevB.87.085434
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000315146600005 Publication Date 2013-02-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 29 Open Access
  Notes ; This work was supported by the EuroGRAPHENE programme of the ESF (project CONGRAN), the Serbian Ministry of Education, Science, and Technological Development, and the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:107661 Serial 137
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Author Phung, Q.M.; Vancoillie, S.; Pourtois, G.; Swerts, J.; Pierloot, K.; Delabie, A.
  Title Atomic layer deposition of ruthenium on a titanium nitride surface : a density functional theory study Type A1 Journal article
  Year (down) 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
  Volume 117 Issue 38 Pages 19442-19453
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Because of its excellent properties in nanotechnology applications, atomic layer deposition of ruthenium (Ru) has been the subject of numerous experimental studies. Recently, two different Ru precursors were compared for plasma-enhanced atomic layer deposition (PEALD) of Ru, and their reactivity was found to be different. Inhibition was observed for bis(ethylcyclopentadienyl)ruthenium (Ru(EtCp)(2)), while nearly linear growth behavior was observed for (methylcyclopentadienyl-pyrrolyl)ruthenium (Ru(MeCp)Py). To understand this difference in reactivity, we investigate the adsorption of RuCp, and RuCpPy (i.e., without substituents) on a TiN surface using calculations based on periodic boundary conditions density functional theory (DFT) combined with experiments based on Rutherford backscattering spectroscopy (RBS). The calculations demonstrate that the RuCpPy precursor chemisorbs on the TiN(100) surface while the RuCp2 precursor only physisorbs. We propose a reaction mechanism for the chemisorption of RuCpPy. The area density of the calculated RuCpPy surface species is compared with the experimental values from RBS. The impact of a H-plasma is also investigated. The DFT calculations and experimental results from RBS provide insight into the adsorption processes of the RuCpPy and RuCp2 precursors on the TiN(100) surface.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000330162500022 Publication Date 2013-08-28
  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 6 Open Access
  Notes Approved Most recent IF: 4.536; 2013 IF: 4.835
  Call Number UA @ lucian @ c:irua:114855 Serial 170
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Author Gómez-Graña, S.; Goris, B.; Altantzis, T.; Fernández-López, C.; Carbó-Argibay, E.; Guerrero-Martínez, A.; Almora-Barrios, N.; López, N.; Pastoriza-Santos, I.; Pérez-Juste, J.; Bals, S.; Van Tendeloo, G.; Liz-Marzán, L.M.;
  Title Au@Ag nanoparticles : halides stabilize {100} facets Type A1 Journal article
  Year (down) 2013 Publication The journal of physical chemistry letters Abbreviated Journal J Phys Chem Lett
  Volume 4 Issue 13 Pages 2209-2216
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Seed-mediated growth is the most efficient methodology to control the size and shape of colloidal metal nanoparticles. In this process, the final nanocrystal shape is defined by the crystalline structure of the initial seed as well as by the presence of ligands and other additives that help to stabilize certain crystallographic facets. We analyze here the growth mechanism in aqueous solution of silver shells on presynthesized gold nanoparticles displaying various well-defined crystalline structures and morphologies. A thorough three-dimensional electron microscopy characterization of the morphology and internal structure of the resulting core-shell nanocrystals indicates that {100} facets are preferred for the outer silver shell, regardless of the morphology and crystallinity of the gold cores. These results are in agreement with theoretical analysis based on the relative surface energies of the exposed facets in the presence of halide ions.
  Address
  Corporate Author Thesis
  Publisher American Chemical Society Place of Publication Washington, D.C Editor
  Language Wos 000321809500018 Publication Date 2013-06-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1948-7185; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 9.353 Times cited 131 Open Access
  Notes 267867 Plasmaquo; 246791 COUNTATOMS; 262348 ESMI; FWO Approved Most recent IF: 9.353; 2013 IF: 6.687
  Call Number UA @ lucian @ c:irua:109811 Serial 204
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Author Milovanovic, S.P.; Masir, M.R.; Peeters, F.M.
  Title Bilayer graphene Hall bar with a pn-junction Type A1 Journal article
  Year (down) 2013 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 114 Issue 11 Pages 113706
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We investigate the magnetic field dependence of the Hall and the bend resistances for a ballistic Hall bar structure containing a pn-junction sculptured from a bilayer of graphene. The electric response is obtained using the billiard model, and we investigate the cases of bilayer graphene with and without a band gap. Two different conduction regimes are possible: (i) both sides of the junction have the same carrier type and (ii) one side of the junction is n-type while the other one is p-type. The first case shows Hall plateau-like features in the Hall resistance that fade away as the band gap opens. The second case exhibits a bend resistance that is asymmetric in magnetic field as a consequence of snake states along the pn-interface, where the maximum is shifted away from zero magnetic field.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000324827200031 Publication Date 2013-09-17
  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 3 Open Access
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 2.068; 2013 IF: 2.185
  Call Number UA @ lucian @ c:irua:111169 Serial 234
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Author Neek-Amal, M.; Beheshtian, J.; Sadeghi, A.; Michel, K.H.; Peeters, F.M.
  Title Boron nitride mono layer : a strain-tunable nanosensor Type A1 Journal article
  Year (down) 2013 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
  Volume 117 Issue 25 Pages 13261-13267
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract The influence of triaxial in-plane strain on the electronic properties of a hexagonal boron-nitride sheet is investigated using density functional theory. Different from graphene, the triaxial strain localizes the molecular orbitals of the boron-nitride flake in its center depending on the direction of the applied strain. The proposed technique for localizing the molecular orbitals that are close to the Fermi level in the center of boron nitride flakes can be used to actualize engineered nanosensors, for instance, to selectively detect gas molecules. We show that the central part of the strained flake adsorbs polar molecules more strongly as compared with an unstrained sheet.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000321236400041 Publication Date 2013-06-03
  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 38 Open Access
  Notes ; This work was supported by the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Funding of the Flemish government. AS. would like to thank the Universiteit Antwerpen for its hospitality. ; Approved Most recent IF: 4.536; 2013 IF: 4.835
  Call Number UA @ lucian @ c:irua:109829 Serial 249
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Author de Sousa, A.A.; Chaves, A.; Farias, G.A.; Peeters, F.M.
  Title Braess paradox at the mesoscopic scale Type A1 Journal article
  Year (down) 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 88 Issue 24 Pages 245417-6
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We theoretically demonstrate that the transport inefficiency recently found experimentally for branched-out mesoscopic networks can also be observed in a quantum ring of finite width with an attached central horizontal branch. This is done by investigating the time evolution of an electron wave packet in such a system. Our numerical results show that the conductivity of the ring does not necessary improve if one adds an extra channel. This ensures that there exists a quantum analog of the Braess paradox, originating from quantum scattering and interference.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000328680500011 Publication Date 2013-12-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 17 Open Access
  Notes ; This work was financially supported by PRONEX/CNPq/FUNCAP and the bilateral project CNPq-FWO. Discussions with J. S. Andrade, Jr. are gratefully acknowledged. A. A. S. has been financially supported by CAPES, under PDSE Contract No. BEX 7177/13-5. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
  Call Number UA @ lucian @ c:irua:113705 Serial 253
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Author da Pieve, F.; Hogan, C.; Lamoen, D.; Verbeeck, J.; Vanmeert, F.; Radepont, M.; Cotte, M.; Janssens, K.; Gonze, X.; Van Tendeloo, G.
  Title Casting light on the darkening of colors in historical paintings Type A1 Journal article
  Year (down) 2013 Publication Physical review letters Abbreviated Journal Phys Rev Lett
  Volume 111 Issue 20 Pages 208302-208305
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract The degradation of colors in historical paintings affects our cultural heritage in both museums and archeological sites. Despite intensive experimental studies, the origin of darkening of one of the most ancient pigments known to humankind, vermilion (α-HgS), remains unexplained. Here, by combining many-body theoretical spectroscopy and high-resolution microscopic x-ray diffraction, we clarify the composition of the damaged paint work and demonstrate possible physicochemical processes, induced by illumination and exposure to humidity and air, that cause photoactivation of the original pigment and the degradation of the secondary minerals. The results suggest a new path for the darkening process which was never considered by previous studies and prompt a critical examination of their findings.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000327244500003 Publication Date 2013-11-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.462 Times cited 30 Open Access
  Notes Vortex; ERC FP7; COUNTATOMS; ECASJO_; Approved Most recent IF: 8.462; 2013 IF: 7.728
  Call Number UA @ lucian @ c:irua:111396UA @ admin @ c:irua:111396 Serial 287
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Author Kirsanova, M.A.; Mori, T.; Maruyama, S.; Abakumov, A.M.; Van Tendeloo, G.; Olenev, A.; Shevelkov, A.V.
  Title Cationic clathrate of type-III Ge172-xPxTey (y\approx21,5, x\approx2y) : synthesis, crystal structure and thermoelectric properties Type A1 Journal article
  Year (down) 2013 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
  Volume 52 Issue 14 Pages 8272-8279
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract A first germanium-based cationic clathrate of type-III, Ge129.3P42.7Te21.53, was synthesized and structurally characterized (space group P42/mnm, a = 19.948(3) Å, c = 10.440(2) Å, Z = 1). In its crystal structure, germanium and phosphorus atoms form three types of polyhedral cages centered with Te atoms. The polyhedra share pentagonal and hexagonal faces to form a 3D framework. Despite the complexity of the crystal structure, the Ge129.3P42.7Te21.53 composition corresponds to the Zintl counting scheme with a good accuracy. Ge129.3P42.7Te21.53 demonstrates semiconducting/insulating behavior of electric resistivity, high positive Seebeck coefficient (500 μV K1 at 300 K), and low thermal conductivity (<0.92 W m1 K1) within the measured temperature range.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Easton, Pa Editor
  Language Wos 000322087100052 Publication Date 2013-06-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.857 Times cited 3 Open Access
  Notes Countatoms Approved Most recent IF: 4.857; 2013 IF: 4.794
  Call Number UA @ lucian @ c:irua:109214 Serial 301
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Author Zhao, C.X.; Xu, W.; Peeters, F.M.
  Title Cerenkov emission of terahertz acoustic-phonons from graphene Type A1 Journal article
  Year (down) 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
  Volume 102 Issue 22 Pages 222101-222104
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We present a theoretical study of the electrical generation of acoustic-phonon emission from graphene at room temperature. The drift velocity (v(x)) and temperature of electrons driven by dc electric field (F-x) are determined by solving self-consistently the momentum-and energy-balance equations derived from the Boltzmann equation. We find that in the presence of impurity, acoustic-and optic-phonon scattering, v(x) can be much larger than the longitudinal (v(l)) and transverse (v(t)) sound velocities in graphene even within the linear response regime. As a result, although the acoustic Cerenkov effect cannot be obviously seen in the analytical formulas, the enhanced acoustic-phonon emission can be observed with increasing F-x when v(x) > v(l) and v > v(t). The frequency of acoustic-phonon emission from graphene can be above 10 THz, which is much higher than that generated from conventional semiconductor systems. This study is pertinent to the application of graphene as hypersonic devices such as terahertz sound sources. (C) 2013 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000320621600034 Publication Date 2013-06-03
  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 25 Open Access
  Notes ; This work was supported by the National Natural Science Foundation of China (Grant No. 10974206), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; Approved Most recent IF: 3.411; 2013 IF: 3.515
  Call Number UA @ lucian @ c:irua:109607 Serial 305
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Author Borgatti, F.; Park, C.; Herpers, A.; Offi, F.; Egoavil, R.; Yamashita, Y.; Yang, A.; Kobata, M.; Kobayashi, K.; Verbeeck, J.; Panaccione, G.; Dittmann, R.;
  Title Chemical insight into electroforming of resistive switching manganite heterostructures Type A1 Journal article
  Year (down) 2013 Publication Nanoscale Abbreviated Journal Nanoscale
  Volume 5 Issue 9 Pages 3954-3960
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract We have investigated the role of the electroforming process in the establishment of resistive switching behaviour for Pt/Ti/Pr0.5Ca0.5MnO3/SrRuO3 layered heterostructures (Pt/Ti/PCMO/SRO) acting as non-volatile Resistance Random Access Memories (RRAMs). Electron spectroscopy measurements demonstrate that the higher resistance state resulting from electroforming of as-prepared devices is strictly correlated with the oxidation of the top electrode Ti layer through field-induced electromigration of oxygen ions. Conversely, PCMO exhibits oxygen depletion and downward change of the chemical potential for both resistive states. Impedance spectroscopy analysis, supported by the detailed knowledge of these effects, provides an accurate model description of the device resistive behaviour. The main contributions to the change of resistance from the as-prepared (low resistance) to the electroformed (high resistance) states are respectively due to reduced PCMO at the boundary with the Ti electrode and to the formation of an anisotropic np junction between the Ti and the PCMO layers.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000317859400051 Publication Date 2013-03-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.367 Times cited 40 Open Access
  Notes Vortex; Countatoms ECASJO_; Approved Most recent IF: 7.367; 2013 IF: 6.739
  Call Number UA @ lucian @ c:irua:108710UA @ admin @ c:irua:108710 Serial 348
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Author Khan, A.W.; Jan, F.; Saeed, A.; Zaka-ul-Islam, M.; Abrar, M.; Khattak, N.A.D.; Zakaullah, M.
  Title Comparative study of electron temperature and excitation temperature in a magnetic pole enhanced-inductively coupled argon plasma Type A1 Journal article
  Year (down) 2013 Publication Current applied physics Abbreviated Journal Curr Appl Phys
  Volume 13 Issue 7 Pages 1241-1246
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Magnetic Pole Enhanced-Inductively Coupled Plasmas (MaPE-ICPs) in analogy to the conventional ICPs exhibit two modes of operation, depending on the power coupling mechanism, i.e., a low power mode with dominant capacitive coupling (E-mode) and a high power mode with dominant inductive coupling (H-mode). A comparative study of the electron temperature measured by a Langmuir probe (T-e(LP)) and the electron excitation temperature (T-exc(OES)) determined by Optical Emission Spectroscopy (OES) is reported in the two distinct modes of a MaPE-ICP operated in argon. The dependence of T-e(LP), T-exc(OES) and their ratio (T-e(LP)/T-exc(OES)) on applied power (5-50 W) and gas pressure (15-60 mTorr) is explored, and the validity of T-exc(OES) as an alternative diagnostic to T-e(LP) is tested in the two modes of MaPE-ICP. The OES based non-invasive measurement of the plasma parameters such as electron temperature is very useful for plasma processing applications in which probe measurements are limited. (C) 2013 Elsevier B. V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos 000322631400014 Publication Date 2013-04-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1567-1739; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.971 Times cited 13 Open Access
  Notes Approved Most recent IF: 1.971; 2013 IF: 2.026
  Call Number UA @ lucian @ c:irua:110718 Serial 421
Permanent link to this record
 

 
Author Petrovic, M.D.; Peeters, F.M.; Chaves, A.; Farias, G.A.
  Title Conductance maps of quantum rings due to a local potential perturbation Type A1 Journal article
  Year (down) 2013 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
  Volume 25 Issue 49 Pages 495301-495309
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We performed a numerical simulation of the dynamics of a Gaussian shaped wavepacket inside a small sized quantum ring, smoothly connected to two leads and exposed to a perturbing potential of a biased atomic force microscope tip. Using the Landauer formalism, we calculated conductance maps of this system in the case of single and two subband transport. We explain the main features in the conductance maps as due to the AFM tip influence on the wavepacket phase and amplitude. In the presence of an external magnetic field, the tip modifies the phi(0) periodic Aharonov-Bohm oscillation pattern into a phi(0)/2 periodic Al'tshuler-Aronov-Spivak oscillation pattern. Our results in the case of multiband transport suggest tip selectivity to higher subbands, making them more observable in the total
  Address
  Corporate Author Thesis
  Publisher Place of Publication London Editor
  Language Wos 000327181400002 Publication Date 2013-11-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.649 Times cited 12 Open Access
  Notes ; This work was supported by the Methusalem programme of the Flemish government, the CNPq-FWO bilateral programme and PNPD and FUNCAP/PRONEX grants. ; Approved Most recent IF: 2.649; 2013 IF: 2.223
  Call Number UA @ lucian @ c:irua:112694 Serial 478
Permanent link to this record
 

 
Author Zarenia, M.
  Title Confined states in mono- and bi-layer grapheme nanostructures Type Doctoral thesis
  Year (down) 2013 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:108668 Serial 485
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