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Author Lindner, H.; Murtazin, A.; Groh, S.; Niemax, K.; Bogaerts, A.
Title Simulation and experimental studies on plasma temperature, flow velocity, and injector diameter effects for an inductively coupled plasma Type A1 Journal article
Year 2011 Publication Analytical chemistry Abbreviated Journal Anal Chem
Volume 83 Issue 24 Pages 9260-9266
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract An inductively coupled plasma (ICP) is analyzed by means of experiments and numerical simulation. Important plasma properties are analyzed, namely, the effective temperature inside the central channel and the mean flow velocity inside the plasma. Furthermore, the effect of torches with different injector diameters is studied by the model. The temperature inside the central channel is determined from the end-on collected line-to-background ratio in dependence of the injector gas flow rates. Within the limits of 3% deviation, the results of the simulation and the experiments are in good agreement in the range of flow rates relevant for the analysis of relatively large droplets, i.e., 50 μm. The deviation increases for higher gas flow rates but stays below 6% for all flow rates studied. The velocity of the gas inside the coil region was determined by side-on analyte emission measurements with single monodisperse droplet introduction and by the analysis of the injector gas path lines in the simulation. In the downstream region significantly higher velocities were found than in the upstream region in both the simulation and the experiment. The quantitative values show good agreement in the downstream region. In the upstream region, deviations were found in the absolute values which can be attributed to the flow conditions in that region and because the methods used for velocity determination are not fully consistent. Eddy structures are found in the simulated flow lines. These affect strongly the way taken by the path lines of the injector gas and they can explain the very long analytical signals found in the experiments at low flow rates. Simulations were performed for different injector diameters in order to find conditions where good analyte transport and optimum signals can be expected. The results clearly show the existence of a transition flow rate which marks the lower limit for effective analyte transport conditions through the plasma. A rule-of-thumb equation was extracted from the results from which the transition flow rate can be estimated for different injector diameters and different injector gas compositions.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000297946900013 Publication Date 2011-07-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.32 Times cited 34 Open Access
Notes Approved Most recent IF: 6.32; 2011 IF: 5.856
Call Number UA @ lucian @ c:irua:94001 Serial 3009
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Author Khalilov, U.; Neyts, E.C.; Pourtois, G.; van Duin, A.C.T.
Title Can we control the thickness of ultrathin silica layers by hyperthermal silicon oxidation at room temperature? Type A1 Journal article
Year 2011 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C
Volume 115 Issue 50 Pages 24839-24848
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Using reactive molecular dynamics simulations by means of the ReaxFF potential, we studied the growth mechanism of ultrathin silica (SiO2) layers during hyperthermal oxidation at room temperature. Oxidation of Si(100){2 × 1} surfaces by both atomic and molecular oxygen was investigated in the energy range 15 eV. The oxidation mechanism, which differs from thermal oxidation, is discussed. In the case of oxidation by molecular O2, silica is quickly formed and the thickness of the formed layers remains limited compared to oxidation by atomic oxygen. The Si/SiO2 interfaces are analyzed in terms of partial charges and angle distributions. The obtained structures of the ultrathin SiO2 films are amorphous, including some intrinsic defects. This study is important for the fabrication of silica-based devices in the micro- and nanoelectronics industry, and more specifically for the fabrication of metal oxide semiconductor devices.
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Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000297947700050 Publication Date 2011-11-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 36 Open Access
Notes Approved Most recent IF: 4.536; 2011 IF: 4.805
Call Number UA @ lucian @ c:irua:94303 Serial 273
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Author Sorée, B.; Magnus, W.; Vandenberghe, W.
Title Low-field mobility in ultrathin silicon nanowire junctionless transistors Type A1 Journal article
Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 99 Issue 23 Pages 233509-233509,3
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We theoretically investigate the phonon, surface roughness and ionized impurity limited low-field mobility of ultrathin silicon n-type nanowire junctionless transistors in the long channel approximation with wire radii ranging from 2 to 5 nm, as function of gate voltage. We show that surface roughness scattering is negligible as long as the wire radius is not too small and ionized impurity scattering is the dominant scattering mechanism. We also show that there exists an optimal radius where the ionized impurity limited mobility exhibits a maximum.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000298006100095 Publication Date 2011-12-09
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 20 Open Access
Notes ; This work is supported by the EU project SQWIRE (FP7-ICT-STREP nr. 257111). William Vandenberghe gratefully acknowledges the Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ; Approved Most recent IF: 3.411; 2011 IF: 3.844
Call Number UA @ lucian @ c:irua:92865 Serial 1850
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Author Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M.; Axt, V.M.
Title Parity-fluctuation induced enlargement of the ratio \DeltaE/kBTc in metallic grains Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 21 Pages 214518-214518,12
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate how the interplay of quantum confinement and particle number-parity fluctuations affects superconducting correlations in ultra-small metallic grains. Using the number-parity projected BCS formalism we calculate the critical temperature and the excitation gap as a function of the grain size for grains with even and odd number of confined carriers. We show that the experimentally observed anomalous increase of the coupling ratio ΔE/kBTc with decreasing superconducting grain size can be attributed to an enhancement of the number-parity fluctuations in ultra-small grains.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000298114100003 Publication Date 2011-12-16
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 14 Open Access
Notes ; This work was supported by the European Community under a Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flamish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). M. D. C. thanks A. S. Mel'nikov and N. B. Kopnin for fruitful discussions. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:94373 Serial 2555
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Author Kontozova-Deutsch, V.; Deutsch, F.; Bencs, L.; Krata, A.; Van Grieken, R.; De Wael, K.
Title Optimization of the ion chromatographic quantification of airborne fluoride, acetate and formate in the Metropolitan Museum of Art, New York Type A1 Journal article
Year 2011 Publication Talanta : the international journal of pure and applied analytical chemistry Abbreviated Journal Talanta
Volume 86 Issue Pages 372-376
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Ion chromatographic (IC) methods have been compared in order to achieve an optimal separation of fluoride, acetate and formate under various elution conditions on two formerly introduced analytical columns (i and ii) and a novel one (iii): (i) an IonPac AS14 (250 mm × 4 mm I.D.), (ii) Allsep A-2 (150 mm × 4.6 mm I.D.), and (iii) an IC SI-50 4E (250 mm (length) × 4 mm (internal diameter – I.D.)). The IC conditions for the separation of the anions concerned were optimized on the IC SI-50 4E column. A near baseline separation of these anions was attained on the IonPac AS14, whereas the peaks of fluoride and acetate could not be resolved on the Allsep A-2. A baseline separation for the three anions was achieved on the IC SI-50 4E column, when applying an eluent mixture of 3.2 mmol/L Na2CO3 and 1.0 mmol/L NaHCO3 with a flow rate of 1.0 mL/min. The highest precision of 1.7, 3.0 and 2.8% and the best limits of detection (LODs) of 0.014, 0.22 and 0.17 mg/L for fluoride, acetate and formate, respectively, were obtained with the IC SI-50 4E column. Hence, this column was applied for the determination of the acetic and formic acid contents of air samples taken by means of passive gaseous sampling at the Metropolitan Museum of Art in New York, USA. Atmospheric concentrations of acetic and formic acid up to 1050 and 450 μg/m3, respectively, were found in non-aerated showcases of the museum. In galleries and outdoors, rather low levels of acetic and formic acid were detected with average concentrations of 50 and 10 μg/m3, respectively. The LOD data of acetate and formate on the IC SI-50 4E column correspond to around 0.5 μg/m3 for both acetic and formic acid in air samples.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000298126300048 Publication Date 2011-09-24
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 19 Open Access
Notes ; The authors gratefully acknowledge the support of Marco Leona and the staff of the Metropolitan Museum of Art in New York during the sampling campaigns. The technical assistance and advice by Dr. Takashi Kotsuka and Shodex Benelux are acknowledged as well. ; Approved Most recent IF: 4.162; 2011 IF: 3.794
Call Number UA @ admin @ c:irua:92066 Serial 5762
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Author He, Z.; Maurice, J.-L.; Gohier, A.; Lee, C.S.; Pribat, D.; Cojocaru, C.S.
Title Iron catalysts for the growth of carbon nanofibers : Fe, Fe3C or both? Type A1 Journal article
Year 2011 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 23 Issue 24 Pages 5379-5387
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Iron is a widely used catalyst for the growth of carbon nanotubes (CNTs) or carbon nanofibers (CNFs) by catalytic chemical vapor deposition. However, both Fe and FeC compounds (generally, Fe3C) have been found to catalyze the growth of CNTs/CNFs, and a comparison study of their respective catalytic activities is still missing. Furthermore, the control of the crystal structure of iron-based catalysts, that is α-Fe or Fe3C, is still a challenge, which not only obscures our understanding of the growth mechanisms of CNTs/CNFs, but also complicates subsequent procedures, such as the removal of catalysts for better industrial applications. Here, we show a partial control of the phase of iron catalysts (α-Fe or Fe3C), obtained by varying the growth temperatures during the synthesis of carbon-based nanofibers/nanotubes in a plasma-enhanced chemical vapor deposition reactor. We also show that the structure of CNFs originating from Fe3C is bamboo-type, while that of CNFs originating from Fe is not. Moreover, we directly compare the growth rates of carbon-based nanofibers/nanotubes during the same experiments and find that CNFs/CNTs grown by α-Fe nanoparticles are longer than CNFs grown from Fe3C nanoparticles. The influence of the type of catalyst on the growth of CNFs is analyzed and the corresponding possible growth mechanisms, based on the different phases of the catalysts, are discussed.
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Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos (up) 000298197300014 Publication Date 2011-11-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 91 Open Access
Notes Approved Most recent IF: 9.466; 2011 IF: 7.286
Call Number UA @ lucian @ c:irua:94297 Serial 1748
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Author Grodzińska, D.; Evers, W.H.; Dorland, R.; van Rijssel, J.; van Huis, M.A.; Meijerink, A.; de Mello Donegá, C.; Vanmaekelbergh, D.
Title Two-fold emission from the S-shell of PbSe/CdSe core/shell quantum dots Type A1 Journal article
Year 2011 Publication Small Abbreviated Journal Small
Volume 7 Issue 24 Pages 3493-3501
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The optical properties of PbSe/CdSe core/shell quantum dots with core sizes smaller than 4 nm in the 5300 K range are reported. The photoluminescence spectra show two peaks, which become increasingly separated in energy as the core diameter is reduced below 4 nm. It is shown that these peaks are due to intrinsic exciton transitions in each quantum dot, rather than emission from different quantum dot sub-ensembles. Most likely, the energy separation between the peaks is due to inter-valley coupling between the L-points of PbSe. The temperature dependence of the relative intensities of the peaks implies that the two emitting states are not in thermal equilibrium and that dark exciton states must play an important role.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos (up) 000298298300012 Publication Date 2011-10-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1613-6810; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 8.643 Times cited 23 Open Access
Notes Approved Most recent IF: 8.643; 2011 IF: 8.349
Call Number UA @ lucian @ c:irua:94371 Serial 3781
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Author Jochems, P.; Satyawali, Y.; van Roy, S.; Doyen, W.; Diels, L.; Dejonghe, W.
Title Characterization and optimization of \beta-galactosidase immobilization process on a mixed-matrix membrane Type A1 Journal article
Year 2011 Publication Enzyme and microbial technology Abbreviated Journal
Volume 49 Issue 6/7 Pages 580-588
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract β-Galactosidase is an important enzyme catalyzing not only the hydrolysis of lactose to the monosaccharides glucose and galactose but also the transgalactosylation reaction to produce galacto-oligosaccharides (GOS). In this study, β-galactosidase was immobilized by adsorption on a mixed-matrix membrane containing zirconium dioxide. The maximum β-galactosidase adsorbed on these membranes was 1.6 g/m2, however, maximal activity was achieved at an enzyme concentration of around 0.5 g/m2. The tests conducted to investigate the optimal immobilization parameters suggested that higher immobilization can be achieved under extreme parameters (pH and temperature) but the activity was not retained at such extreme operational parameters. The investigations on immobilized enzymes indicated that no real shift occurred in its optimal temperature after immobilization though the activity in case of immobilized enzyme was better retained at lower temperature (5 °C). A shift of 0.5 unit was observed in optimal pH after immobilization (pH 6.5 to 7). Perhaps the most striking results are the kinetic parameters of the immobilized enzyme; while the Michaelis constant (Km) value increased almost eight times compared to the free enzyme, the maximum enzyme velocity (Vmax) remained almost constant.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000298529600015 Publication Date 2011-06-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0141-0229 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:90060 Serial 7608
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Author Nikolova, I.; Janssen, S.; Vos, P.; Vrancken, K.; Mishra, V.; Berghmans, P.
Title Dispersion modelling of traffic induced ultrafine particles in a street canyon in Antwerp, Belgium and comparison with observations Type A1 Journal article
Year 2011 Publication The science of the total environment Abbreviated Journal
Volume 412 Issue Pages 336-343
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The aim of this study is to investigate the dispersion of ultrafine particles and its spatial distribution in a street canyon and its neighbourhood with the 3D CFD model ENVI-met®. The performance of the model at street scale is evaluated and the importance of the boundary conditions like wind field and traffic emissions on the UFP concentration is demonstrated. To support and validate the modelled results, a short-term measurement campaign was conducted in a street canyon in Antwerp, Belgium. The UFP concentration was measured simultaneously with P-TRACK (TSI Model 8525) at four different locations in the canyon. The modelled UFP concentrations compare well with the measured data (correlation coefficient R from 0.44 to 0.93) within the standard deviation of the measurements. Despite the moderate traffic flow in the street canyon, UFP concentrations in the canyon are in general double of the background concentrations, indicating the high local contribution for this particle number concentration. Some of the observed concentration profiles are not resembled by the model simulations. For these specific anomalies, further analysis is performed and plausible explanations are put forward. The role of wind direction and traffic emissions is investigated. The performance evaluation of ENVI-met® shows that in general the model qualitatively and quantitatively describes the dispersion of UFP in the street canyon study.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000298534300038 Publication Date 2011-10-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697; 1879-1026 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:94377 Serial 7815
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Author Yang, X.-Y.; Tian, G.; Chen, L.-H.; Li, Y.; Rooke, J.C.; Wei, Y.-X.; Liu, Z.-M.; Deng, Z.; Van Tendeloo, G.; Su, B.-L.
Title Well-organized zeolite nanocrystal aggregates with interconnected hierarchically micro-meso-macropore systems showing enhanced catalytic performance Type A1 Journal article
Year 2011 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J
Volume 17 Issue 52 Pages 14987-14995
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Preparation and characterization of well-organized zeolitic nanocrystal aggregates with an interconnected hierarchically micromesomacro porous system are described. Amorphous nanoparticles in bimodal aluminosilicates were directly transformed into highly crystalline nanosized zeolites, as well as acting as scaffold template. All pores on three length scales incorporated in one solid body are interconnected with each other. These zeolitic nanocrystal aggregates with hierarchically micromesomacroporous structure were thoroughly characterized. TEM images and 29Si NMR spectra showed that the amorphous phase of the initial material had been completely replaced by nanocrystals to give a micromesomacroporous crystalline zeolitic structure. Catalytic testing demonstrated their superiority due to the highly active sites and the presence of interconnected micromesomacroporosity in the cracking of bulky 1,3,5-triisopropylbenzene (TIPB) compared to traditional zeolite catalysts. This synthesis strategy was extended to prepare various zeolitic nanocrystal aggregates (ZSM-5, Beta, TS-1, etc.) with well-organized hierarchical micromesomacroporous structures.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos (up) 000298547300035 Publication Date 2011-11-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0947-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.317 Times cited 61 Open Access
Notes Approved Most recent IF: 5.317; 2011 IF: 5.925
Call Number UA @ lucian @ c:irua:96274 Serial 3913
Permanent link to this record
 
 
Author Nowak, M.P.; Szafran, B.; Peeters, F.M.
Title Fano resonances and electron spin transport through a two-dimensional spin-orbit-coupled quantum ring Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 23 Pages 235319-235319,8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Electron transport through a spin-orbit-coupled quantum ring is investigated within linear response theory. We show that the finite width of the ring results in the appearance of Fano resonances in the conductance. This turns out to be a consequence of the spin-orbit interaction that leads to a breaking of the parity of the states localized in the ring. The resonances appear when the system is close to maxima of Aharonov-Casher conductance oscillations where spin transfer is heavily modified. When the spin-orbit coupling strength is detuned from the Aharonov-Casher maxima the resonances are broadened resulting in a dependence of the spin transport on the electron Fermi energy in contrast to predictions from one-dimensional models.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000298605700002 Publication Date 2011-12-29
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 19 Open Access
Notes ; This work was supported by the “Krakow Interdisciplinary PhD Project in Nanoscience and Advanced Nanostructures” operated within the Foundation for Polish Science MPD Programme cofinanced by the EU European Regional Development Fund, Project No. N N202103938 supported by the Ministry of Science and Higher Education (MNiSW) for 2010-2013, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1). This research was supported in part by PL-Grid Infrastructure. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:94292 Serial 1171
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Author Cooper, D.; Rouvière, J.-L.; Béché, A.; Kadkhodazadeh, S.; Semenova, E.S.; Dunin-Borkowsk, R.
Title Quantitative strain mapping of InAs/InP quantum dots with 1 nm spatial resolution using dark field electron holography Type A1 Journal article
Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 99 Issue Pages 261911-261913
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The optical properties of semiconductor quantum dots are greatly influenced by their strain state. Dark field electron holography has been used to measure the strain in InAsquantum dotsgrown in InP with a spatial resolution of 1 nm. A strain value of 5.4% ± 0.1% has been determined which is consistent with both measurements made by geometrical phase analysis of high angle annular dark field scanning transmission electron microscopy images and with simulations.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000298638500027 Publication Date 2012-01-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; 1077-3118 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 26 Open Access
Notes Approved Most recent IF: 3.411; 2011 IF: 3.844
Call Number UA @ lucian @ c:irua:136428 Serial 4507
Permanent link to this record
 
 
Author Elia, A.; De Wael, K.; Dowsett, M.; Adriaens, A.
Title Electrochemical deposition of a copper carboxylate layer on copper as potential corrosion inhibitor Type A1 Journal article
Year 2011 Publication Journal of solid state electrochemistry Abbreviated Journal J Solid State Electr
Volume 16 Issue 1 Pages 143-148
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Carboxylic acids and sodium carboxylates are used to protect metals against aqueous and atmospheric corrosion. In this paper, we describe the application of a layer of copper carboxylate on the surface of a copper electrode by means of cyclic voltammetry technique and tests which measure the corresponding resistance to aqueous corrosion. Unlike the soaking process, which also forms a film on the surface, the use of cyclic voltammetry allows one to follow the deposition process of the copper carboxylates onto the electrode. The modified electrodes have been characterised with infrared spectroscopy. In addition, the corrosion resistance of the film has been investigated using polarisation resistance and Tafel plot measurements.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000298651700018 Publication Date 2011-01-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1432-8488 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.316 Times cited 8 Open Access
Notes ; Authors would like to acknowledge the Research Foundation-Flanders (FWO) for funding assistance (A. Elia is a FWO aspirant) and V. Vermeersch and S. Van Vlierberghe (Ghent University, Polymer Chemistry and Biomaterials Research Group) for the FTIR-ATR measurements. ; Approved Most recent IF: 2.316; 2011 IF: 2.131
Call Number UA @ admin @ c:irua:89618 Serial 5588
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Author Guttmann, P.; Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Umek, P.; Arcon, D.; Ewels, C.P.; Rehbein, S.; Heim, S.; Schneider, G.
Title TXM-NEXAFS of TiO2-based nanostructures Type P1 Proceeding
Year 2011 Publication AIP conference proceedings Abbreviated Journal
Volume 1365 Issue Pages 437-440
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract In this work, electronic properties of individual TiOx-pristine nanoribbons (NR) prepared by hydrothermal treatment of anatase TiO(2) micro-particles were studied using the HZB transmission x-ray microscope (TXM) at the BESSY II undulator beamline U41-FSGM. NEXAFS is ideally suited to study TiO(2)-based materials because both the O K-edge and Ti L-edge features are very sensitive to the local bonding environment, providing diagnostic information about the crystal structures and oxidation states of various forms of titanium oxides and sub-oxides. TXM-NEXAFS combines full-field x-ray microscopy with spectroscopy, allowing the study of the electronic structure of individual nanostructures with spatial resolution better than 25 nm and a spectral resolution of up to E/Delta E = 10000. The typical image field in TXM-NEXAFS measurements is about 10 mu m. 10 mu m, which is large compared to the individual nanoparticle. Therefore, one image stack already contains statistically significant data. In addition, the directional electric field vector ((E) over bar) of the x-rays can be used as a “search tool” for the direction of chemical bonds of the atom selected by its absorption edge.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos (up) 000298672400103 Publication Date 2011-09-19
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 2 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113071 Serial 3789
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Author Buytaert, V.; Muys, B.; Devriendt, N.; Pelkmans, L.; Kretzschmar, J.G.; Samson, R.
Title Towards integrated sustainability assessment for energetic use of biomass : a state of the art evaluation of assessment tools Type A1 Journal article
Year 2011 Publication Renewable and sustainable energy reviews Abbreviated Journal
Volume 15 Issue 8 Pages 3918-3933
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Biomass is expected to play an increasingly significant role in the greening of energy supply. Nevertheless, concerns are rising about the sustainability of large-scale energy crop production. Impacts must be assessed carefully before deciding whether and how this industry should be developed, and what technologies, policies and investment strategies should be pursued. There is need for a comprehensive and reliable sustainability assessment tool to evaluate the environmental, social and economic performance of biomass energy production. This paper paves the way for such a tool by analysing and comparing the performance and applicability of a selection of existing tools that are potentially useful for sustainability assessment of bioenergy systems. The selected tools are: Criteria And Indicators (C&I), Life Cycle Assessment (LCA), Environmental Impact Assessment (EIA), Cost Benefit Analysis (CBA), Exergy Analysis (EA) and System Perturbation Analysis (SPA). To evaluate the tools, a framework was constructed that consists of four evaluation levels: sustainability issues, tool attributes, model structure, area of application. The tools were then evaluated using literature data and with the help of a Delphi panel of experts. Finally, a statistical analysis was performed on the resulting data matrix to detect significant differences between tools. It becomes clear that none of the selected tools is able to perform a comprehensive sustainability assessment of bioenergy systems. Every tool has its particular advantages and disadvantages, which means that trade-offs are inevitable and a balance must be found between scientific accuracy and pragmatic decision making. A good definition of the assessment objective is therefore crucial. It seems an interesting option to create a toolbox that combines procedural parts of C&I and EIA, supplemented with calculation algorithms of LCA and CBA for respectively environmental and economic sustainability indicators. Nevertheless, this would require a more comprehensive interdisciplinary approach to align the different tool characteristics and focuses.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000298764100043 Publication Date 2011-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1364-0321; 1879-0690 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:96444 Serial 8682
Permanent link to this record
 
 
Author Denneulin, T.; Rouvière, J.L.; Béché, A.; Py, M.; Barnes, J.P.; Rochat, N.; Hartmann, J.M.; Cooper, D.
Title The reduction of the substitutional C content in annealed Si/SiGeC superlattices studied by dark-field electron holography Type A1 Journal article
Year 2011 Publication Semiconductor science and technology Abbreviated Journal Semicond Sci Tech
Volume 26 Issue 12 Pages 1-10
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Si/Si(1 − x − y)GexCy superlattices are used in the construction of new microelectronic architectures such as multichannel transistors. The introduction of carbon in SiGe allows for compensation of the strain and to avoid plastic relaxation. However, the formation of incoherent β-SiC clusters during annealing limits the processability of SiGeC. This precipitation leads to a modification of the strain in the alloy due to the reduction of the substitutional carbon content. Here, we investigated the strain in annealed Si/Si0.744Ge0.244C0.012 superlattices grown by reduced pressure chemical vapour deposition using dark-field electron holography. The variation of the substitutional C content was calculated by correlating the results with finite-element simulations. The obtained values were then compared with Fourier-transformed infrared spectrometry measurements. It was shown that after annealing for 2 min at 1050 °C carbon no longer has any influence on strain in the superlattice, which behaves like pure SiGe. However, a significant proportion of substitutional C atoms remain in a third-nearest neighbour (3nn) configuration. It was deduced that the influence of 3nn C on strain is negligible and that only isolated atoms have a significant contribution. It was also proposed that the 3nn configuration is an intermediary step during the formation of SiC clusters.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000300151300010 Publication Date 2011-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0268-1242 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.305 Times cited Open Access
Notes Approved Most recent IF: 2.305; 2011 IF: 1.723
Call Number UA @ lucian @ c:irua:136427 Serial 4508
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Author Peirs, J.; Verleysen, P.; Tirry, W.; Rabet, L.; Schryvers, D.; Degrieck, J.
Title Dynamic shear localization in Ti6Al4V Type P1 Proceeding
Year 2011 Publication Procedia Engineering T2 – 11th International Conference on the Mechanical Behavior of Materials, (ICM), 2011, Como, ITALY (ICM11) Abbreviated Journal
Volume Issue Pages 1-6
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract The alloy Ti6Al4V is known to be prone to the formation of adiabatic shear bands when dynamically loaded in shear. This causes a catastrophic decrease of the load carrying capacity and is usually followed by fracture. Although, the main mechanism is recognized to be the competition between strain hardening and thermal softening, a detailed understanding of the role of microstructural plasticity mechanisms and macroscopic loading conditions does not exist yet. To study strain localization and shear fracture, different high strain rate shear tests have been carried out: compression of hat-shaped specimens, torsion of thin walled tubular specimens and in-plane shear tests. The value of the three techniques in studying shear localization is evaluated. Post-mortem analysis of the fracture surface and the materials' microstructure is performed with optical and electron microscopy. In all cases a ductile fracture is observed. SEM and TEM techniques are used to study the local microstructure and composition in the shear band and as such the driving mechanism for the ASB formation. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of ICM11
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000300451302060 Publication Date 2011-06-20
Series Editor Series Title Abbreviated Series Title
Series Volume 10 Series Issue Edition
ISSN 1877-7058; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 4 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113069 Serial 767
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Author Verbeeck, J.; Bertoni, G.; Lichte, H.
Title A holographic biprism as a perfect energy filter? Type A1 Journal article
Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 111 Issue 7 Pages 887-893
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It has often been stated that a holographic biprism represents a near perfect energy filter and only elastically scattered electrons can participate in the interference fringes. This is based on the assumption that the reference wave does not contain inelastically scattered electrons. In this letter we show that this is not exactly true because of the delocalised inelastic interaction of the reference wave with the sample. We experimentally and theoretically show that inelastic scattering plays a role in the fringe formation, but it is shown that this contribution is small and can usually be neglected in practice. (C) 2011 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000300461000021 Publication Date 2011-02-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 13 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 2.843; 2011 IF: 2.471
Call Number UA @ lucian @ c:irua:97250UA @ admin @ c:irua:97250 Serial 1482
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Author Xu, Q.; Zandbergen, H.W.; van Dyck, D.
Title Applying an information transmission approach to extract valence electron information from reconstructed exit waves Type A1 Journal article
Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 111 Issue 7 Pages 912-919
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract The knowledge of the valence electron distribution is essential for understanding the properties of materials. However this information is difficult to obtain from HREM images because it is easily obscured by the large scattering contribution of core electrons and by the strong dynamical scattering process. In order to develop a sensitive method to extract the information of valence electrons, we have used an information transmission approach to describe the electron interaction with the object. The scattered electron wave is decomposed in a set of basic functions, which are the eigen functions of the Hamiltonian of the projected electrostatic object potential. Each basic function behaves as a communication channel that transfers the information of the object with its own transmission characteristic. By properly combining the components of the different channels, it is possible to design a scheme to extract the information of valence electron distribution from a series of exit waves. The method is described theoretically and demonstrated by means of computer simulations.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000300461000024 Publication Date 2011-02-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 1 Open Access
Notes Fwo Approved Most recent IF: 2.843; 2011 IF: 2.471
Call Number UA @ lucian @ c:irua:93623 Serial 146
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Author van den Broek, W.; Van Aert, S.; Goos, P.; van Dyck, D.
Title Throughput maximization of particle radius measurements by balancing size and current of the electron probe Type A1 Journal article
Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 111 Issue 7 Pages 940-947
Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab
Abstract In thispaperweinvestigatewhichprobesizemaximizesthethroughputwhenmeasuringtheradiusof nanoparticlesinhighangleannulardarkfieldscanningtransmissionelectronmicroscopy(HAADFSTEM). The sizeandthecorrespondingcurrentoftheelectronprobedeterminetheprecisionoftheestimateofa particlesradius.Maximizingthroughputmeansthatamaximumnumberofparticlesshouldbeimaged withinagiventimeframe,sothataprespecifiedprecisionisattained.WeshowthatBayesianstatistical experimentaldesignisaveryusefulapproachtodeterminetheoptimalprobesizeusingacertainamount of priorknowledgeaboutthesample.Thedependenceoftheoptimalprobesizeonthedetectorgeometry and thediameter,variabilityandatomicnumberoftheparticlesisinvestigated.Anexpressionforthe optimalprobesizeintheabsenceofanykindofpriorknowledgeaboutthespecimenisderivedaswell.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000300461000026 Publication Date 2010-11-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 7 Open Access
Notes Approved Most recent IF: 2.843; 2011 IF: 2.471
Call Number UA @ lucian @ c:irua:89657 Serial 3659
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Author Goris, B.; Bals, S.; van den Broek, W.; Verbeeck, J.; Van Tendeloo, G.
Title Exploring different inelastic projection mechanisms for electron tomography Type A1 Journal article
Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 111 Issue 8 Pages 1262-1267
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Several different projection mechanisms that all make use of inelastically scattered electrons are used for electron tomography. The advantages and the disadvantages of these methods are compared to HAADFSTEM tomography, which is considered as the standard electron tomography technique in materials science. The different inelastic setups used are energy filtered transmission electron microscopy (EFTEM), thickness mapping based on the log-ratio method and bulk plasmon mapping. We present a comparison that can be used to select the best inelastic signal for tomography, depending on different parameters such as the beam stability and nature of the sample. The appropriate signal will obviously also depend on the exact information which is requested.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000300461100039 Publication Date 2011-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 21 Open Access
Notes Fwo; Iap; Esteem 026019 Approved Most recent IF: 2.843; 2011 IF: 2.471
Call Number UA @ lucian @ c:irua:91260UA @ admin @ c:irua:91260 Serial 1151
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Author Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D.
Title A method to determine the local surface profile from reconstructed exit waves Type A1 Journal article
Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 111 Issue 8 Pages 1352-1359
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Reconstructed exit waves are useful to quantify unknown structure parameters such as the position and composition of the atom columns at atomic scale. Existing techniques provide a complex wave in a flat plane which is close to the plane where the electrons leave the atom columns. However, due to local deviation in the flatness of the exit surface, there will be an offset between the plane of reconstruction and the actual exit of a specific atom column. Using the channelling theory, it has been shown that this defocus offset can in principle be determined atom column-by-atom column. As such, the surface roughness could be quantified at atomic scale. However, the outcome strongly depends on the initial plane of reconstruction especially in a crystalline structure. If this plane is further away from the true exit, the waves of the atom columns become delocalized and interfere mutually which strongly complicates the interpretation of the exit wave in terms of the local structure. In this paper, we will study the delocalization with defocus using the channelling theory in a more systematic way.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000300461100049 Publication Date 2011-05-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 3 Open Access
Notes Fwo Approved Most recent IF: 2.843; 2011 IF: 2.471
Call Number UA @ lucian @ c:irua:88941 Serial 2017
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Author Schattschneider, P.; Verbeeck, J.
Title Theory of free electron vortices Type A1 Journal article
Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 111 Issue 9/10 Pages 1461-1468
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The recent creation of electron vortex beams and their first practical application motivates a better understanding of their properties. Here, we develop the theory of free electron vortices with quantized angular momentum, based on solutions of the Schrödinger equation for cylindrical boundary conditions. The principle of transformation of a plane wave into vortices with quantized angular momentum, their paraxial propagation through round magnetic lenses, and the effect of partial coherence are discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000300461200002 Publication Date 2011-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 57 Open Access
Notes Esteem 026019 Approved Most recent IF: 2.843; 2011 IF: 2.471
Call Number UA @ lucian @ c:irua:91882 Serial 3617
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Author de Backer, A.; Van Aert, S.; van Dyck, D.
Title High precision measurements of atom column positions using model-based exit wave reconstruction Type A1 Journal article
Year 2011 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 111 Issue 9/10 Pages 1475-1482
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract In this paper, it has been investigated how to measure atom column positions as accurately and precisely as possible using a focal series of images. In theory, it is expected that the precision would considerably improve using a maximum likelihood estimator based on the full series of focal images. As such, the theoretical lower bound on the variances of the unknown atom column positions can be attained. However, this approach is numerically demanding. Therefore, maximum likelihood estimation has been compared with the results obtained by fitting a model to a reconstructed exit wave rather than to the full series of focal images. Hence, a real space model-based exit wave reconstruction technique based on the channelling theory is introduced. Simulations show that the reconstructed complex exit wave contains the same amount of information concerning the atom column positions as the full series of focal images. Only for thin samples, which act as weak phase objects, this information can be retrieved from the phase of the reconstructed complex exit wave.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000300461200004 Publication Date 2011-07-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 8 Open Access
Notes Fwo Approved Most recent IF: 2.843; 2011 IF: 2.471
Call Number UA @ lucian @ c:irua:91879 Serial 1438
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Author Sels, D.; Sorée, B.; Groeseneken, G.
Title Quantum ballistic transport in the junctionless nanowire pinch-off field effect transistor Type A1 Journal article
Year 2011 Publication Journal of computational electronics Abbreviated Journal J Comput Electron
Volume 10 Issue 1 Pages 216-221
Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)
Abstract In this work we investigate quantum ballistic transport in ultrasmall junctionless and inversion mode semiconducting nanowire transistors within the framework of the self-consistent Schrödinger-Poisson problem. The quantum transmitting boundary method is used to generate open boundary conditions between the active region and the electron reservoirs. We adopt a subband decomposition approach to make the problem numerically tractable and make a comparison of four different numerical approaches to solve the self-consistent Schrödinger-Poisson problem. Finally we discuss the IV-characteristics for small (r≤5 nm) GaAs nanowire transistors. The novel junctionless pinch-off FET or junctionless nanowire transistor is extensively compared with the gate-all-around (GAA) nanowire MOSFET.
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos (up) 000300735800021 Publication Date 2011-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1569-8025;1572-8137; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.526 Times cited 12 Open Access
Notes ; ; Approved Most recent IF: 1.526; 2011 IF: 1.211
Call Number UA @ lucian @ c:irua:89501 Serial 2772
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Author Austing, D.G.; Payette, C.; Yu, G.; Gupta, J.A.; Aers, G.C.; Nair, S.V.; Partoens, B.; Amaha, S.; Tarucha, S.
Title Characterization and modeling of single-particle energy levels and resonant currents in a coherent quantum dot mixer Type P1 Proceeding
Year 2011 Publication AIP conference proceedings T2 – 30th International Conference on the Physics of Semiconductors (ICPS-30), JUL 25-30, 2010, Seoul, SOUTH KOREA Abbreviated Journal
Volume Issue Pages 1-2
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract We characterize and model the single-particle energy level position and resonant current strength at a three-level crossing in a coherent mixer composed of two weakly coupled vertical quantum dots. In addition to clear anticrossing behavior, an otherwise strong resonance is completely extinguished at the center of the crossing. Despite the strong variation in energy level position and resonant current strength throughout the crossing region, the resonance widths and the sum of the branch currents are found to be approximately constant.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos (up) 000301053000453 Publication Date 2011-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume 1399 Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113070 Serial 314
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Author Delville, R.; Shi, H.; James, R.D.; Schryvers, D.
Title Special microstructures and twin features in Ti50Ni50-x(Pd,Au)x at small hysteresis Type A1 Journal article
Year 2011 Publication Diffusion and defect data : solid state data : part B : solid state phenomena Abbreviated Journal
Volume 172/174 Issue Pages 105-110
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The breaking of symmetry due to atomic displacements in the austenite-martensite phase transformation generally leads to their crystallographic incompatibility. Energy minimizing accommodation mechanisms such as martensite twinning have been recently shown to be a source of hysteresis and irreversible plastic deformation. Compatibility between the two phases can however be achieved by carefully tuning lattice parameters through composition change. A dramatic drop in hysteresis and novel microstructures such as a lowering of the amount of twin lamella are then observed. Related theoretical and simulation works also support the existence of such microstructures including peculiar self-accommodating configurations at near-compatibility. We present the transmission electron microscopy (TEM) study of these novel microstructures for the alloy systems Ti50Ni50-xPdx and Ti50Ni50-xAux where the composition was systemically tuned to approach perfect compatibility. High resolution imaging of the interface between austenite and martensite supplies evidences of compatibility at the atomic level.
Address
Corporate Author Thesis
Publisher Place of Publication Vaduz Editor
Language Wos (up) 000303359700016 Publication Date 2011-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9779; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:90155 Serial 3069
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Author Schryvers, D.; Tirry, W.; Cao, S.
Title Advanced TEM and SEM methods applied to 3D nano- and microstructural investigations of Ni4Ti3 precipitates in Ni-Ti (SMA) Type A1 Journal article
Year 2011 Publication Diffusion and defect data : solid state data : part B : solid state phenomena Abbreviated Journal
Volume 172/174 Issue Pages 229-235
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Two different kinds of experimental approaches yielding three-dimensional structural information on metastable semi-coherent precipitates are demonstrated. By combining high-resolution images from two independent viewing directions a full description of the strain field surrounding a nano-sized Ni4Ti3 precipitate in Ni-Ti can be obtained. The principal axes and strains correlate well with the transformation strain of the observed R-phase transformation close to the precipitate. Using a slice-and-view procedure in a FIB/SEM dual-beam instrument, a three-dimensional voxel dataset is produced from which morphological and distributional information on the same precipitates can be obtained yielding new insight into the particular transformation paths of these alloys, relevant for their functional behaviour.
Address
Corporate Author Thesis
Publisher Place of Publication Vaduz Editor
Language Wos (up) 000303359700036 Publication Date 2011-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9779; 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 @ lucian @ c:irua:90153 Serial 73
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Author Delville, R.; Malard, B.; Pilch, J.; Sittner, P.; Schryvers, D.
Title Transmission electron microscopy study of microstructural evolution in nanograined Ni-Ti microwires heat treated by electric pulse Type A1 Journal article
Year 2011 Publication Diffusion and defect data : solid state data : part B : solid state phenomena Abbreviated Journal
Volume 172/174 Issue Pages 682-687
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Transmission electron microscopy and mechanical testing were employed to investigate the evolution of microstructure and functional superelastic properties of 0.1mm diameter as-drawn Ni-Ti wires subjected to a non-conventional heat treatment by controlled electric pulse current. This method enables a finer control of the recovery and recrystallisation processes taking place during the heat treatment and accordingly a better control on the final microstructure. The best functional properties were obtained for heat-treated Ni-Ti wires having a nanograined microstructure (20-50 nm) partially recovered through polygonization and partially recrystallized. Such microstructure is highly resistant against dislocation slip upon cycling, while microstructures annealed for longer time and showing mostly recrystallized grains were prone to dislocation slip, particularly as the grain size exceeds 100 nm. The density of dislocation defects increased significantly with increasing grain size of the microstructure. The activity of three <100>/{011} slip systems was identified in the largest grains of 500-1200 nm. An additional mode of plastic deformation, {114} compound austenite twinning, was observed in the largest grains of fully recrystallized microstructures. It is proposed that dislocation slip (and possibly deformation twinning) occurring in superelastic cycling is coupled with the stress-induced martensitic transformation.
Address
Corporate Author Thesis
Publisher Place of Publication Vaduz Editor
Language Wos (up) 000303359700105 Publication Date 2011-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9779; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:90154 Serial 3717
Permanent link to this record
 
 
Author Cao, S.; Nishida, M.; Schryvers, D.
Title FIB/SEM applied to quantitative 3D analysis of precipitates in Ni-Ti Type A1 Journal article
Year 2011 Publication Diffusion and defect data : solid state data : part B : solid state phenomena Abbreviated Journal
Volume 172/174 Issue Pages 1284-1289
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ni4Ti3 precipitates with a heterogeneous distribution growing in a polycrystalline Ni50.8Ti49.2 alloy have been investigated in a Dual-Beam FIB/SEM system. The volume ratio, mean volume, central plane diameter, thickness, aspect ratio and sphericity of the precipitates in the grain interior as well as near to the grain boundary were measured or calculated. The morphology of the precipitates was classified according to the Zingg scheme. The multistage martensitic transformation occurring in these kinds of samples is interpreted in view of the data of this heterogeneous microstructure of matrix and precipitates.
Address
Corporate Author Thesis
Publisher Place of Publication Vaduz Editor
Language Wos (up) 000303359700199 Publication Date 2011-07-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1662-9779; ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:90152 Serial 1188
Permanent link to this record