Records |
Author |
Bittencourt, C.; Navio, C.; Nicolay, A.; Ruelle, B.; Godfroid, T.; Snyders, R.; Colomer, J.-F.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Suarez-Martinez, I.; Ewels, C.P. |
Title |
Atomic oxygen functionalization of vertically aligned carbon nanotubes |
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 |
42 |
Pages |
20412-20418 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Vertically aligned multiwalled carbon nanotubes (v-MWCNTs) are functionalized using atomic oxygen generated in a microwave plasma. X-ray photoelectron spectroscopy depth profile analysis shows that the plasma treatment effectively grafts oxygen exclusively at the v-MWCNT tips. Electron microscopy shows that neither the vertical alignment nor the structure of v-MWCNTs were affected by the plasma treatment. Density functional calculations suggest assignment of XPS C 1s peaks at 286.6 and 287.5 eV, to epoxy and carbonyl functional groups, respectively. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000296205600009 |
Publication Date |
2011-10-04 |
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 |
31 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: 4.536; 2011 IF: 4.805 |
Call Number |
UA @ lucian @ c:irua:91890 |
Serial |
174 |
Permanent link to this record |
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|
|
Author |
Müller, M.; Turner, S.; Lebedev, O.I.; Wang, Y.; Van Tendeloo, G.; Fischer, R.A. |
Title |
Au@MOF-5 and Au/Mox@MOF-5 (M = Zn, Ti; x = 1, 2) : preparation and microstructural characterisation |
Type |
A1 Journal article |
Year |
2011 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
Volume |
|
Issue |
12 |
Pages |
1876-1887 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The Zn-carboxylate-based porous coordination polymer MOF-5 [Zn4O(bdc)3] and the metal oxide loaded materials ZnO@MOF-5 and TiO2@MOF-5 were loaded in a second step with the precursor [ClAuCO] to yield intermediate materials denoted as [ClAuCO]@MOF-5, [ClAuCO]/ZnO@MOF-5 and [ClAuCO]/TiO2@MOF-5. These composites were decomposed to Au@MOF-5, Au/ZnO@MOF-5 and Au/TiO2@MOF-5 under hydrogen at 100 °C. The nanoparticle-loaded hybrid materials were characterised by powder X-ray diffraction (PXRD), IR spectroscopy, X-ray photoelectron spectroscopy (XPS) and N2 sorption measurements, which reveal an intact MOF-5 structure that maintains a high specific surface area. For Au@MOF-5, crystalline Au nanoparticles were distributed over the MOF matrix in a homogeneous fashion with a size of ca. 13 nm, evidenced by high resolution transmission electron microscopy. In the case of Au/ZnO@MOF-5, the Au and metal oxide particles of a few nm in size were coexistent in a given volume of the MOF-5 matrix and were not separated in different crystalline MOF particles. For the TiO2 loaded materials the oxide is preferentially located near the outer surface of the MOF particles, leading to an increase of larger exterior Au particles in comparison to very small interior Au particles as observed for the other materials. Au@MOF-5, Au/ZnO@MOF-5 and Au/TiO2@MOF-5 were tested in liquid-phase oxidation of alcohols. Preliminary results show a high activity for the Au loaded materials in this reaction. This observation is attributed to the microstructure of the composites with very small Au particles distributed homogeneously over the MOF matrix. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000289644300004 |
Publication Date |
2011-03-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-1948; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.444 |
Times cited |
75 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.444; 2011 IF: 3.049 |
Call Number |
UA @ lucian @ c:irua:88644 |
Serial |
205 |
Permanent link to this record |
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|
|
Author |
Molina, L.; Tan, H.; Biermans, E.; Batenburg, K.J.; Verbeeck, J.; Bals, S.; Van Tendeloo, G. |
Title |
Barrier efficiency of sponge-like La2Zr2O7 buffer layers for YBCO-coated conductors |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
24 |
Issue |
6 |
Pages |
065019-065019,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different film processing methods can yield similar microstructural features such as nanovoids and nanometer-sized La2Zr2O7 grains. Nanoporosity is a typical feature found in such films and the implications for the functionality of the films are investigated by a combination of scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) and quantitative electron tomography. Chemical solution based La2Zr2O7 films deposited on flexible Ni5 at.%W substrates with a {100}lang001rang biaxial texture were prepared for an in-depth characterization. A sponge-like structure composed of nanometer-sized voids is revealed by high-angle annular dark-field scanning transmission electron microscopy in combination with electron tomography. A three-dimensional quantification of nanovoids in the La2Zr2O7 film is obtained on a local scale. Mostly non-interconnected highly faceted nanovoids compromise more than one-fifth of the investigated sample volume. The diffusion barrier efficiency of a 170 nm thick La2Zr2O7 film is investigated by STEM-EELS, yielding a 1.8 ± 0.2 nm oxide layer beyond which no significant nickel diffusion can be detected and intermixing is observed. This is of particular significance for the functionality of YBa2Cu3O7 − δ coated conductor architectures based on solution derived La2Zr2O7 films as diffusion barriers. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000290472900021 |
Publication Date |
2011-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
31 |
Open Access |
|
Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 2.878; 2011 IF: 2.662 |
Call Number |
UA @ lucian @ c:irua:88639UA @ admin @ c:irua:88639 |
Serial |
221 |
Permanent link to this record |
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|
|
Author |
Yusupov, M.; Bultinck, E.; Depla, D.; Bogaerts, A. |
Title |
Behavior of electrons in a dual-magnetron sputter deposition system : a Monte Carlo model |
Type |
A1 Journal article |
Year |
2011 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
13 |
Issue |
|
Pages |
033018-033018,17 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A Monte Carlo model has been developed for investigating the electron behavior in a dual-magnetron sputter deposition system. To describe the three-dimensional (3D) geometry, different reference frames, i.e. a local and a global coordinate system, were used. In this study, the influence of both closed and mirror magnetic field configurations on the plasma properties is investigated. In the case of a closed magnetic field configuration, the calculated electron trajectories show that if an electron is emitted in (or near) the center of the cathode, where the influence of the magnetic field is low, it is able to travel from one magnetron to the other. On the other hand, when an electron is created at the race track area, it is more or less trapped in the strong magnetic field and cannot easily escape to the second magnetron region. In the case of a mirror magnetic field configuration, irrespective of where the electron is emitted from the cathode, it cannot travel from one magnetron to the other because the magnetic field lines guide the electron to the substrate. Moreover, the electron density and electron impact ionization rate have been calculated and studied in detail for both configurations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000289064600001 |
Publication Date |
2011-03-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2011 IF: 4.177 |
Call Number |
UA @ lucian @ c:irua:87544 |
Serial |
224 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Peeters, F.M. |
Title |
Binary dusty plasma Coulomb balls |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
83 |
Issue |
4 |
Pages |
041136,1-041136,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigated the mixing and segregation of a system consisting of two different species of particles, having different charges, interacting through a pure Coulomb potential, and confined in a three-dimensional parabolic trap. The structure of the cluster and its normal mode spectrum are analyzed as a function of the relative charge and the relative number of different types of particles. We found that (a) the system can be in a mixed or segregated state depending on the relative charge ratio parameter and (b) the segregation process is mediated by a first or second order structural phase transition which strongly influences the magic cluster properties of the system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000290154900004 |
Publication Date |
2011-04-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by FACEPE (Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.366; 2011 IF: 2.255 |
Call Number |
UA @ lucian @ c:irua:89716 |
Serial |
236 |
Permanent link to this record |
|
|
|
Author |
Neek-Amal, M.; Peeters, F.M. |
Title |
Buckled circular monolayer graphene : a graphene nano-bowl |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
23 |
Issue |
4 |
Pages |
045002-045002,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the stability of circular monolayer graphene subjected to a radial load using non-equilibrium molecular dynamics simulations. When monolayer graphene is radially stressed, after some small circular strain (~0.4%) it buckles and bends into a new bowl-like shape. Young's modulus is calculated from the linear relation between stress and strain before the buckling threshold, which is in agreement with experimental results. The prediction of elasticity theory for the buckling threshold of a radially stressed plate is presented and its results are compared to the one of our atomistic simulation. The Jarzynski equality is used to estimate the difference between the free energy of the non-compressed states and the buckled states. From a calculation of the free energy we obtain the optimum radius for which the system feels the minimum boundary stress. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000286142800003 |
Publication Date |
2010-12-16 |
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 |
27 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
Call Number |
UA @ lucian @ c:irua:88043 |
Serial |
259 |
Permanent link to this record |
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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. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
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 |
Permanent link to this record |
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|
|
Author |
Martens, J.A.; Thybaut, J.W.; Denayer, J.F.M.; Sree, S.P.; Aerts, A.; Reyniers, M.-F.; van Speybroeck, V.; Waroquier, M.; Buekenhoudt, A.; Vankelecom, I.; Buijs, W.; Persoons, J.; Baron, G.V.; Bals, S.; Van Tendeloo, G.; Marin, G.B.; Jacobs, P.A.; Kirschhock, C.E.A. |
Title |
Catalytic and molecular separation properties of Zeogrids and Zeotiles |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Catalysis today |
Abbreviated Journal |
Catal Today |
Volume |
168 |
Issue |
1 |
Pages |
17-27 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Zeogrids and Zeotiles are hierarchical materials built from assembled MFI zeolite precursor units. Permanent secondary porosity in these materials is obtained through self assembly of nanoparticles encountered in MFI zeolite synthesis in the presence of supramolecular templates. Hereon, the aggregated species are termed nanoslabs. Zeogrids are layered materials with lateral spacings between nanoslabs creating galleries qualifying as supermicropores. Zeotiles present a diversity of tridimensional nanoslab assemblies with mesopores. Zeotile-1, -4 and -6 are hexagonal mesostructures. Zeotile-1 has triangular and hexagonal channels; Zeotile-4 has hexagonal channels interconnected via slits. Zeotile-2 has a cubic structure with gyroid type mesoporosity. The behavior of Zeogrids and Zeotiles in adsorption, membrane and chromatographic separation and catalysis has been characterized and compared with zeolites and mesoporous materials derived from unstructured silica sources. Shape selectivity was detected via adsorption of n- and iso-alkanes. The mesoporosity of Zeotiles can be exploited in chromatographic separation of biomolecules. Zeotiles present attractive separation properties relevant to CO2 sequestration. Because of its facile synthesis procedure without hydrothermal steps Zeogrid is convenient for membrane synthesis. The performance of Zeogrid membrane in gas separation, nanofiltration and pervaporation is reported. In the Beckmann rearrangement of cyclohexanone oxime Zeogrids and Zeotiles display a catalytic activity characteristic of silicalite-1 zeolites. Introduction of acidity and redox catalytic activity can be achieved via incorporation of Al and Ti atoms in the nanoslabs during synthesis. Zeogrids are active in hydrocracking, catalytic cracking, alkylation and epoxidation reactions. Zeogrids and Zeotiles often behave differently from ordered mesoporous materials as well as from zeolites and present a valuable extension of the family of hierarchical silicate based materials. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000291033300003 |
Publication Date |
2011-03-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0920-5861; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.636 |
Times cited |
13 |
Open Access |
|
Notes |
Fwo; Iap
Sbo |
Approved |
Most recent IF: 4.636; 2011 IF: 3.407 |
Call Number |
UA @ lucian @ c:irua:88647 |
Serial |
290 |
Permanent link to this record |
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|
|
Author |
Yan, L.; Niu, H.J.; Duong, G.V.; Suchomel, M.R.; Bacsa, J.; Chalker, P.R.; Hadermann, J.; Van Tendeloo, G.; Rosseinsky, M.J. |
Title |
Cation ordering within the perovskite block of a six-layer Ruddlesden-Popper oxide from layer-by-layer growth artificial interfaces in complex unit cells |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Chemical science |
Abbreviated Journal |
Chem Sci |
Volume |
2 |
Issue |
2 |
Pages |
261-272 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The (AO)(ABO3)n Ruddlesden-Popper structure is an archetypal complex oxide consisting of two distinct structural units, an (AO) rock salt layer separating an n-octahedra thick perovskite block. Conventional high-temperature oxide synthesis methods cannot access members with n > 3, but low-temperature layer-by-layer thin film methods allow the preparation of materials with thicker perovskite blocks, exploiting high surface mobility and lattice matching with the substrate. This paper describes the growth of an n = 6 member CaO[(CSMO)2(LCMO)2 (CSMO)2] in which the six unit cell perovskite block is sub-divided into two central La0.67Ca0.33MnO3 (LCMO) and two terminal Ca0.85Sm0.15MnO3 (CSMO) layers to allow stabilization of the rock salt layer and variation of the transition metal charge. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Royal Society of Chemistry |
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000286327600010 |
Publication Date |
2010-11-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-6520;2041-6539; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.668 |
Times cited |
16 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.668; 2011 IF: 7.525 |
Call Number |
UA @ lucian @ c:irua:88652 |
Serial |
300 |
Permanent link to this record |
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|
|
Author |
Neyts, E.C.; van Duin, A.C.T.; Bogaerts, A. |
Title |
Changing chirality during single-walled carbon nanotube growth : a reactive molecular dynamics/Monte Carlo study |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
133 |
Issue |
43 |
Pages |
17225-17231 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The growth mechanism and chirality formation of a single-walled carbon nanotube (SWNT) on a surface-bound nickel nanocluster are investigated by hybrid reactive molecular dynamics/force-biased Monte Carlo simulations. The validity of the interatomic potential used, the so-called ReaxFF potential, for simulating catalytic SWNT growth is demonstrated. The SWNT growth process was found to be in agreement with previous studies and observed to proceed through a number of distinct steps, viz., the dissolution of carbon in the metallic particle, the surface segregation of carbon with the formation of aggregated carbon clusters on the surface, the formation of graphitic islands that grow into SWNT caps, and finally continued growth of the SWNT. Moreover, it is clearly illustrated in the present study that during the growth process, the carbon network is continuously restructured by a metal-mediated process, thereby healing many topological defects. It is also found that a cap can nucleate and disappear again, which was not observed in previous simulations. Encapsulation of the nanoparticle is observed to be prevented by the carbon network migrating as a whole over the cluster surface. Finally, for the first time, the chirality of the growing SWNT cap is observed to change from (11,0) over (9,3) to (7,7). It is demonstrated that this change in chirality is due to the metal-mediated restructuring process. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000297380900026 |
Publication Date |
2011-10-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
116 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 13.858; 2011 IF: 9.907 |
Call Number |
UA @ lucian @ c:irua:92043 |
Serial |
309 |
Permanent link to this record |
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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 |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
New York |
Editor |
|
Language |
|
Wos |
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 |
Permanent link to this record |
|
|
|
Author |
Bultinck, E.; Bogaerts, A. |
Title |
Characterization of an Ar/O2 magnetron plasma by a multi-species Monte Carlo model |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
4 |
Pages |
045013-045013,12 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A combined Monte Carlo (MC)/analytical surface model is developed to study the plasma processes occurring during the reactive sputter deposition of TiOx thin films. This model describes the important plasma species with a MC approach (i.e. electrons, Ar+ ions, {\rm O}_2 |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000295829800015 |
Publication Date |
2011-06-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:89732 |
Serial |
316 |
Permanent link to this record |
|
|
|
Author |
d' Hondt, H. |
Title |
Characterization of anion deficient perovskites |
Type |
Doctoral thesis |
Year |
2011 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
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:87905 |
Serial |
317 |
Permanent link to this record |
|
|
|
Author |
Tirumalasetty, G.K.; van Huis, M.A.; Fang, C.M.; Xu, Q.; Tichelaar, F.D.; Hanlon, D.N.; Sietsma, J.; Zandbergen, H.W. |
Title |
Characterization of NbC and (Nb, Ti)N nanoprecipitates in TRIP assisted multiphase steels |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
Volume |
59 |
Issue |
19 |
Pages |
7406-7415 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Multiphase steels utilising composite strengthening may be further strengthened via grain refinement or precipitation by the addition of microalloying elements. In this study a Nb microalloyed steel comprising martensite, bainite and retained austenite has been studied. By means of transmission electron microscopy (TEM) we have investigated the size distribution and the structural properties of (Nb, Ti)N and NbC precipitates, their occurrence in the various steel phases, and their relationship with the Fe matrix. (Nb, Ti)N precipitates were found in ferrite, martensite, and bainite, while NbC precipitates were found only in ferrite. All NbC precipitates were found to be small (520 nm in size) and to have a face centred cubic (fcc) crystal structure with lattice parameter a = 4.36 ± 0.05 Å. In contrast, the (Nb, Ti)N precipitates were found to have a broader size range (5150 nm) and to have a fcc crystal structure with lattice parameter a = 8.09 ± 0.05 Å. While the NbC precipitates were found to be randomly oriented, the (Nb, Ti)N precipitates have a well-defined NishiyamaWasserman orientation relationship with the ferrite matrix. An analysis of the lattice mismatch suggests that the latter precipitates have a high potential for effective strengthening. Density functional theory calculations were performed for various stoichiometries of NbCx and NbxTiyNz phases and the comparison with experimental data indicates that both the carbides and nitrides are deficient in C and N content. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000296405200026 |
Publication Date |
2011-09-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1359-6454; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.301 |
Times cited |
58 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 5.301; 2011 IF: 3.755 |
Call Number |
UA @ lucian @ c:irua:93297 |
Serial |
328 |
Permanent link to this record |
|
|
|
Author |
Tikhomirov, A.S.; Sorokina, N.E.; Shornikova, O.N.; Morozov, V.A.; Van Tendeloo, G.; Avdeev, V.V. |
Title |
The chemical vapor infiltration of exfoliated graphite to produce carbon/carbon composites |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
49 |
Issue |
1 |
Pages |
147-153 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Chemical vapor infiltration was used for the production of carbon/carbon composites based on exfoliated graphite and pyrolytic carbon Two different exfoliated graphites compacted to densities of 0 05-0 4 g/cm(3) were used as a preform The influence of the synthesis conditions (temperature, pressure, time etc) on the degree of infiltration, the pyrolytic carbon morphology and the C/C composite characteristics was examined using Raman spectroscopy, scanning electron microscopy and low-temperature nitrogen adsorption (C) 2010 Elsevier Ltd All rights reserved |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000284977500021 |
Publication Date |
2010-09-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
7 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: 6.337; 2011 IF: 5.378 |
Call Number |
UA @ lucian @ c:irua:99185 |
Serial |
354 |
Permanent link to this record |
|
|
|
Author |
Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. |
Title |
Chiral states in bilayer graphene : magnetic field dependence and gap opening |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
12 |
Pages |
125451-125451,13 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
At the interface of electrostatic potential kink profiles, one-dimensional chiral states are found in bilayer graphene (BLG). Such structures can be created by applying an asymmetric potential to the upper and the lower layers of BLG. We found the following: (i) due to the strong confinement by the single kink profile, the unidirectional states are only weakly affected by a magnetic field; (ii) increasing the smoothness of the kink potential results in additional bound states, which are topologically different from those chiral states; and (iii) in the presence of a kink-antikink potential, the overlap between the oppositely moving chiral states results in the appearance of crossing and anticrossing points in the energy spectrum. This leads to the opening of tunable minigaps in the spectrum of the unidirectional topological states. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000295484300016 |
Publication Date |
2011-09-30 |
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 |
50 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), the Brazilian agency CNPq (Pronex), and the bilateral projects between Flanders and Brazil and the collaboration project FWO-CNPq. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:92915 |
Serial |
358 |
Permanent link to this record |
|
|
|
Author |
Wang, Y.; Yu, M.Y.; Chen, Z.Y. |
Title |
Coherent relativistic wake wave of a charged object moving steadily in a plasma |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
Volume |
84 |
Issue |
2 |
Pages |
025501,1-025501,5 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Nonlinear electron plasma waves driven by a finite-charged particle pulse or rigid object moving at relativistic speeds are investigated. Quasi-stationary smooth and spiky wake waves comoving with the object are found. Localized soliton-like solutions are also shown to exist. Relativistic effects tend to prevent their formation because of the electron mass increase. The application of the very-large-amplitude wake density waves as a source of ultrahigh-energy cosmic-ray events is discussed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Stockholm |
Editor |
|
Language |
|
Wos |
000294727900017 |
Publication Date |
2011-07-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-8949;1402-4896; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.28 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.28; 2011 IF: 1.204 |
Call Number |
UA @ lucian @ c:irua:92435 |
Serial |
381 |
Permanent link to this record |
|
|
|
Author |
Pape, E.; Bezerra, T.N.; Vanneste, H.; Heeschen, K.; Moodley, L.; Leroux, F.; van Breugel, P.; Vanreusel, A. |
Title |
Community structure and feeding preference of nematodes associated with methane seepage at the Darwin mud volcano (Gulf of Cádiz) |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Marine ecology progress series |
Abbreviated Journal |
Mar Ecol Prog Ser |
Volume |
438 |
Issue |
|
Pages |
71-83 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We sampled the Darwin mud volcano (MV) for meiofaunal community and trophic structure in relation to pore-water geochemistry along a 10 m transect from a seep site on the rim of the crater towards the MV slope. Pore-water profiles indicated considerable variation in upward methane (CH4) flow among sediment cores taken along the transect, with highest flux in the seep sediment core, gradually decreasing along the transect, to no CH4 flux in the core taken at a 5 m distance. Low sulphate concentrations and high levels of total alkalinity and sulphide (H2S) suggested that anaerobic oxidation of methane (AOM) occurred close to the sediment surface in the seep sediment core. High H2S levels had a genus- and species-specific impact on meiofaunal densities. Nematode genus composition varied gradually between sediment cores, with the genus Sabatieria dominating almost all sediment cores. However, genus diversity increased with increasing distance from the seep site. These limited data suggest that the community structure of seep meiofauna is highly dependent on local (a)biotic habitat characteristics, and a typical seep meiofaunal community cannot be delineated. Stable isotope values suggested the nematode diet up to 10 m from the seep site included thiotrophic carbon. The thicker hemipelagic sediment layer (photosynthetic carbon), the increased trophic diversity, and the heavier nematode δ13C farther from the seep site suggest a decrease in thiotrophy and an increase in photosynthetic carbon in the nematode diet. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Inter-research |
Place of Publication |
Halstenbek |
Editor |
|
Language |
|
Wos |
000295616000006 |
Publication Date |
2011-07-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0171-8630;1616-1599; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.292 |
Times cited |
18 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.292; 2011 IF: 2.711 |
Call Number |
UA @ lucian @ c:irua:93682 |
Serial |
414 |
Permanent link to this record |
|
|
|
Author |
Pham, A.-T.; Zhao, Q.-T.; Jungemann, C.; Meinerzhagen, B.; Mantl, S.; Sorée, B.; Pourtois, G. |
Title |
Comparison of strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs : CV characteristics, mobility, and ON current |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Solid state electronics |
Abbreviated Journal |
Solid State Electron |
Volume |
65-66 |
Issue |
|
Pages |
64-71 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs are investigated including important aspects like CV characteristics, mobility, and ON current. The simulations are based on the self-consistent solution of 6 × 6 k · p Schrödinger Equation, multi subband Boltzmann Transport Equation and Poisson Equation, and capture size quantization, strain, crystallographic orientation, and SiGe alloy effects on a solid physical basis. The simulation results are validated by comparison with different experimental data sources. The simulation results show that the strained SiGe HOI PMOSFET with (1 1 0) surface orientation has a higher gate capacitance and a much higher mobility and ON current compared to a similar device with the traditional (0 0 1) surface orientation. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000297182700012 |
Publication Date |
2011-07-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0038-1101; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.58 |
Times cited |
2 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 1.58; 2011 IF: 1.397 |
Call Number |
UA @ lucian @ c:irua:92866 |
Serial |
433 |
Permanent link to this record |
|
|
|
Author |
Verleysen, E.; Bender, H.; Richard, O.; Schryvers, D.; Vandervorst, W. |
Title |
Compositional characterization of nickel silicides by HAADF-STEM imaging |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of materials science |
Abbreviated Journal |
J Mater Sci |
Volume |
46 |
Issue |
7 |
Pages |
2001-2008 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A methodology for the quantitative compositional characterization of nickel silicides by high angle annular dark field scanning transmission electron microscopy (HAADF-STEM) imaging is presented. HAADF-STEM images of a set of nickel silicide reference samples Ni3Si, Ni31Si12, Ni2Si, NiSi and NiSi2 are taken at identical experimental conditions. The correlation between sample thickness and HAADF-STEM intensity is discussed. In order to quantify the relationship between the experimental Z-contrast intensities and the composition of the analysed layers, the ratio of the HAADF-STEM intensity to the sample thickness or to the intensity of the silicon substrate is determined for each nickel silicide reference sample. Diffraction contrast is still detected on the HAADF-STEM images, even though the detector is set at the largest possible detection angle. The influence on the quantification results of intensity fluctuations caused by diffraction contrast and channelling is examined. The methodology is applied to FUSI gate devices and to horizontal TFET devices with different nickel silicides formed on source, gate and drain. It is shown that, if the elements which are present are known, this methodology allows a fast quantitative 2-dimensional compositional analysis. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000286633000002 |
Publication Date |
2011-01-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-2461;1573-4803; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.599 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.599; 2011 IF: 2.015 |
Call Number |
UA @ lucian @ c:irua:88950 |
Serial |
446 |
Permanent link to this record |
|
|
|
Author |
Parente, A.; Gorlé, C.; van Beeck, J.; Benocci, C. |
Title |
A comprehensive modelling approach for the neutral atmospheric boundary layer : consistent inflow conditions, wall function and turbulence model |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Boundary-layer meteorology |
Abbreviated Journal |
Bound-Lay Meteorol |
Volume |
140 |
Issue |
3 |
Pages |
411-428 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report on a novel approach for the Reynolds-averaged Navier-Stokes (RANS) modelling of the neutral atmospheric boundary layer (ABL), using the standard k− turbulence model. A new inlet condition for turbulent kinetic energy is analytically derived from the solution of the k− model transport equations, resulting in a consistent set of fully developed inlet conditions for the neutral ABL. A modification of the standard k− model is also employed to ensure consistency between the inlet conditions and the turbulence model. In particular, the turbulence model constant C μ is generalized as a location-dependent parameter, and a source term is introduced in the transport equation for the turbulent dissipation rate. The application of the proposed methodology to cases involving obstacles in the flow is made possible through the implementation of an algorithm, which automatically switches the turbulence model formulation when going from the region where the ABL is undisturbed to the region directly affected by the building. Finally, the model is completed with a slightly modified version of the Richards and Hoxey rough-wall boundary condition. The methodology is implemented and tested in the commercial code Ansys Fluent 12.1. Results are presented for a neutral boundary layer over flat terrain and for the flow around a single building immersed in an ABL. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Dordrecht |
Editor |
|
Language |
|
Wos |
000293923800004 |
Publication Date |
2011-05-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0006-8314;1573-1472; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.573 |
Times cited |
54 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.573; 2011 IF: 1.737 |
Call Number |
UA @ lucian @ c:irua:92341 |
Serial |
450 |
Permanent link to this record |
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|
|
Author |
Bogaerts, A.; Eckert, M.; Mao, M.; Neyts, E. |
Title |
Computer modelling of the plasma chemistry and plasma-based growth mechanisms for nanostructured materials |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
44 |
Issue |
17 |
Pages |
174030-174030,16 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this review paper, an overview is given of different modelling efforts for plasmas used for the formation and growth of nanostructured materials. This includes both the plasma chemistry, providing information on the precursors for nanostructure formation, as well as the growth processes itself. We limit ourselves to carbon (and silicon) nanostructures. Examples of the plasma modelling comprise nanoparticle formation in silane and hydrocarbon plasmas, as well as the plasma chemistry giving rise to carbon nanostructure formation, such as (ultra)nanocrystalline diamond ((U)NCD) and carbon nanotubes (CNTs). The second part of the paper deals with the simulation of the (plasma-based) growth mechanisms of the same carbon nanostructures, i.e. (U)NCD and CNTs, both by mechanistic modelling and detailed atomistic simulations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000289512700030 |
Publication Date |
2011-04-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
25 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.588; 2011 IF: 2.544 |
Call Number |
UA @ lucian @ c:irua:88364 |
Serial |
463 |
Permanent link to this record |
|
|
|
Author |
Tinck, S.; Bogaerts, A. |
Title |
Computer simulations of an oxygen inductively coupled plasma used for plasma-assisted atomic layer deposition |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
1 |
Pages |
015008-015008,10 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, an O2 inductively coupled plasma used for plasma enhanced atomic layer deposition of Al2O3 thin films is investigated by means of modeling. This work intends to provide more information about basic plasma properties such as species densities and species fluxes to the substrate as a function of power and pressure, which might be hard to measure experimentally. For this purpose, a hybrid model developed by Kushner et al is applied to calculate the plasma characteristics in the reactor volume for different chamber pressures ranging from 1 to 10 mTorr and different coil powers ranging from 50 to 500 W. Density profiles of the various oxygen containing plasma species are reported as well as fluxes to the substrate under various operating conditions. Furthermore, different orientations of the substrate, which can be placed vertically or horizontally in the reactor, are taken into account. In addition, special attention is paid to the recombination process of atomic oxygen on the different reactor walls under the stated operating conditions. From this work it can be concluded that the plasma properties change significantly in different locations of the reactor. The plasma density near the cylindrical coil is high, while it is almost negligible in the neighborhood of the substrate. Ion and excited species fluxes to the substrate are found to be very low and negligible. Finally, the orientation of the substrate has a minor effect on the flux of O2, while it has a significant effect on the flux of O. In the horizontal configuration, the flux of atomic oxygen can be up to one order of magnitude lower than in the vertical configuration. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000286592200009 |
Publication Date |
2011-01-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:85285 |
Serial |
467 |
Permanent link to this record |
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|
|
Author |
Chaves, A.; Komendová, L.; Milošević, M.V.; Andrade, J.S.; Farias, G.A.; Peeters, F.M. |
Title |
Conditions for nonmonotonic vortex interaction in two-band superconductors |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
21 |
Pages |
214523-214523,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We describe a semianalytic approach to the two-band Ginzburg-Landau theory, which predicts the behavior of vortices in two-band superconductors. We show that the character of the short-range vortex-vortex interaction is determined by the sign of the normal domain-superconductor interface energy, in analogy with the conventional differentiation between type I and type II superconductors. However, we also show that the long-range interaction is determined by a modified Ginzburg-Landau parameter κ*, different from the standard κ of a bulk superconductor. This opens the possibility for nonmonotonic vortex-vortex interaction, which is temperature dependent, and can be further tuned by alterations of the material on the microscopic scale. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000292252300009 |
Publication Date |
2011-06-30 |
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 |
46 |
Open Access |
|
Notes |
; Discussions with A. Moreira, A. Shanenko, R. Prozorov, and A. Golubov are gratefully acknowledged. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the bilateral project FWO-CNPq, CAPES, and PRONEX/CNPq/FUNCAP. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:90922 |
Serial |
477 |
Permanent link to this record |
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|
|
Author |
Peelaers, H.; Partoens, B.; Giantomassi, M.; Rangel, T.; Goossens, E.; Rignanese, G.-M.; Gonze, X.; Peeters, F.M. |
Title |
Convergence of quasiparticle band structures of Si and Ge nanowires in the GW approximation and the validity of scissor shifts |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
4 |
Pages |
045306-045306,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from fully converged density-functional theory calculations, the quasiparticle corrections are calculated for different sized Si and Ge nanowires using the GW approximation. The effectiveness of recently developed techniques in speeding up the convergence of the quasiparticle calculations is demonstrated. The complete quasiparticle band structures are also obtained using an interpolation technique based on maximallylocalized Wannier functions. From the quasiparticle results, we assess the correctness of the commonly applied scissor-shift correction. Dispersion changes are observed, which are also reflected in changes in the effective band masses calculated taking into account quasiparticle corrections. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000286771400004 |
Publication Date |
2011-01-21 |
Series Editor |
|
Series Title |
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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 |
18 |
Open Access |
|
Notes |
; We are grateful to Yann Pouillon for valuable technical support with the build system of ABINIT, related to the WANNIER90 library. This work was supported by the Flemish Science Foundation (FWO-Vl) and by the Interuniversity Attraction Poles Program (P6/42)-Belgian State-Belgian Science Policy. X. G. and G.-M. R. acknowledge funding from the EU's 7th Framework Programme through the ETSF I3 e-Infrastructure project (Grant No. 211956), the Communaute francaise de Belgique through the Action de Recherche Concertee 07/12-003 “Nanosystemes hybrides metal-organiques,” and the Wallon Region Project No. 816849 “ European Theoretical Spectroscopy Facility” (WALL ETSF). M. G. acknowledges funding from the FRFC Project No. 2.4.589.09.F. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:86905 |
Serial |
510 |
Permanent link to this record |
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|
Author |
Klimczuk, T.; Wang, C.H.; Lawrence, J.M.; Xu, Q.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Trouw, F.; Kurita, N.; Tokiwa, Y.; Lee, H.o.; Booth, C.H.; Gardner, J.S.; Bauer, E.D.; Joyce, J.J.; Zandbergen, H.W.; Movshovich, R.; Cava, R.J.; Thompson, J.D.; |
Title |
Crystal fields, disorder, and antiferromagnetic short-range order in Yb0.24Sn0.76Ru |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
7 |
Pages |
075152-075152,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report extensive measurements on a new compound (Yb0.24Sn0.76)Ru that crystallizes in the cubic CsCl structure. Valence-band photoemission (PES) and L3 x-ray absorption show no divalent component in the 4f configuration of Yb. Inelastic neutron scattering (INS) indicates that the eight-fold degenerate J-multiplet of Yb3+ is split by the crystalline electric field (CEF) into a Γ7-doublet ground state and a Γ8 quartet at an excitation energy 20 meV. The magnetic susceptibility can be fit very well by this CEF scheme under the assumption that a Γ6-excited state resides at 32 meV; however, the Γ8/Γ6 transition expected at 12 meV was not observed in the INS. The resistivity follows a Bloch-Grüneisen law shunted by a parallel resistor, as is typical of systems subject to phonon scattering with no apparent magnetic scattering. All of these properties can be understood as representing simple local moment behavior of the trivalent Yb ion. At 1 K there is a peak in specific heat that is too broad to represent a magnetic-phase transition, consistent with absence of magnetic reflections in neutron diffraction. On the other hand this peak also is too narrow to represent the Kondo effect in the Γ7-doublet ground state. On the basis of the field dependence of the specific heat, we argue that antiferromagnetic (AF) short-range order (SRO) (possibly coexisting with Kondo physics) occurs at low temperatures. The long-range magnetic order is suppressed because the Yb site occupancy is below the percolation threshold for this disordered compound. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000293830800003 |
Publication Date |
2011-08-15 |
Series Editor |
|
Series Title |
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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 |
8 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:92427 |
Serial |
555 |
Permanent link to this record |
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Author |
Klimczuk, T.; Wang, C.H.; Xu, Q.; Lawrence, J.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Bauer, E.D.; Griveau, J.-C.; Sadowski, W.; Zandbergen, H.W.; Thompson, J.D.; Cava, R.J. |
Title |
Crystal growth of CsCl-type Yb0.24Sn0.76Ru |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of crystal growth |
Abbreviated Journal |
J Cryst Growth |
Volume |
318 |
Issue |
1 |
Pages |
1005-1008 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The YbRuSn ternary system was investigated and a new material, Yb0.24Sn0.76Ru, with a simple cubic crystal structure, was discovered. Yb0.24Sn0.76Ru has a smaller lattice parameter a=3.217(4) Å, than its isostructural YbRu analogue (a=3.360 Å). Both X-ray diffraction and electron microscopy techniques were used to refine the crystal structure of Yb0.24Sn0.76Ru. It was found that a new compound forms in the CsCl structure, with Ru on the 1a site and a (Yb, Sn) mixture on site 1b. The XRD Rietveld analysis provides the occupation of Yb equal to 0.24, in agreement with the single crystal nano-electron diffraction refinement, which gives the occupation 0.21. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000289653900220 |
Publication Date |
2010-10-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-0248; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.751 |
Times cited |
1 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 1.751; 2011 IF: 1.726 |
Call Number |
UA @ lucian @ c:irua:89966 |
Serial |
556 |
Permanent link to this record |
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Author |
Sullivan, E.; Hadermann, J.; Greaves, C. |
Title |
Crystallographic and magnetic characterisation of the brownmillerite Sr2Co2O5 |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
Volume |
184 |
Issue |
3 |
Pages |
649-654 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Sr2Co2O5 with the perovskite-related brownmillerite structure has been synthesised via quenching, with the orthorhombic unit cell parameters a=5.4639(3) Å, b=15.6486(8) Å and c=5.5667(3) Å based on refinement of neutron powder diffraction data collected at 4 K. Electron microscopy revealed LRLR-intralayer ordering of chain orientations, which require a doubling of the unit cell along the c-parameter, consistent with the assignment of the space group Pcmb. However, on the length scale pertinent to NPD, no long-range order is observed and the disordered space group Imma appears more appropriate. The magnetic structure corresponds to G-type order with a moment of 3.00(4) μB directed along [1 0 0]. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000288587800026 |
Publication Date |
2011-01-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.299 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.299; 2011 IF: 2.159 |
Call Number |
UA @ lucian @ c:irua:89650 |
Serial |
584 |
Permanent link to this record |
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Author |
Corthals, S.; van Noyen, J.; Liang, D.; Ke, X.; Van Tendeloo, G.; Jacobs, P.; Sels, B. |
Title |
A cyclic catalyst pretreatment in CO2 for high yield production of Carbon nanofibers with narrow diameter distribution |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Catalysis letters |
Abbreviated Journal |
Catal Lett |
Volume |
141 |
Issue |
11 |
Pages |
1621-1624 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This paper presents a cyclic catalyst pretreatment process to improve the CNF yield with narrow size distribution by sequentially feeding the CVD reactor with CH4/CO2 mixtures (carbon deposition) and CO2 (carbon removal) prior to the actual growth process. A mechanism based on a break-up of large Ni particles tentatively explains the beneficial effect of the cyclic carbon deposition/removal CVD procedure. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Basel |
Editor |
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Language |
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Wos |
000296471400006 |
Publication Date |
2011-09-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
1011-372X;1572-879X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.799 |
Times cited |
1 |
Open Access |
|
Notes |
Iwt; Iap |
Approved |
Most recent IF: 2.799; 2011 IF: 2.242 |
Call Number |
UA @ lucian @ c:irua:91888 |
Serial |
598 |
Permanent link to this record |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Verbeeck, J.; Tian, H.; Tan, H.; Dik, J.; Radepont, M.; Cotte, M. |
Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
83 |
Issue |
4 |
Pages |
1214-1223 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000287176900011 |
Publication Date |
2011-02-14 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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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 |
113 |
Open Access |
|
Notes |
Iuap; Fwo |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
Call Number |
UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794 |
Serial |
632 |
Permanent link to this record |