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	Author	Hamelet, S.; Casas-Cabanas, M.; Dupont, L.; Davoisne, C.; Tarascon, J.M.; Masquelier, C.
	Title	Existence of superstructures due to large amounts of Fe vacancies in the LiFePO₄-type framework			Type	A1 Journal article
	Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	23	Issue	1	Pages	32-38
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	LiFePO4 has been under intense scrutiny over the past decade because it stands as an attractive positive electrode material for the next generation of Li-ion batteries to power electric vehicles and hybrid electric vehicles, hence the importance of its thermal behavior. The reactivity of LiFePO4 with air at moderate temperatures is shown to be dependent on its particle size. For nanosized materials, a progressive displacement of Fe from the core structure leading to a composite made of nanosize Fe2O3 and highly defective, oxidized LixFeyPO4 compositions, among which the “ideal” formula LiFe2/3PO4. Herein we report, from both temperature-controlled X-ray diffraction and electronic diffraction microscopy, that these off-stoichiometry olivine-type compounds show a defect ordering resulting in the formation of a superstructure. Such a finding shows striking similarities with the temperature-driven oxidation of fayalite Fe2SiO4 (another olivine) to structurally defective laihunite, reported in the literature three decades ago.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000285726900007	Publication Date	2010-12-14
	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	30	Open Access
	Notes				Approved	Most recent IF: 9.466; 2011 IF: 7.286
	Call Number	UA @ lucian @ c:irua:105605			Serial	1130
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	Author	Masir, M.R.; Vasilopoulos, P.; Peeters, F.M.
	Title	Graphene in inhomogeneous magnetic fields : bound, quasi-bound and scattering states			Type	A1 Journal article
	Year	2011	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	23	Issue	31	Pages	315301,1-315301,14
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electron states in graphene-based magnetic dot and magnetic ring structures and combinations of both are investigated. The corresponding spectra are studied as a function of the radii, the strengths of the inhomogeneous magnetic field and of a uniform background field, the strength of an electrostatic barrier and the angular momentum quantum number. In the absence of an external magnetic field we have only long-lived quasi-bound and scattering states and we assess their influence on the density of states. In addition, we consider elastic electron scattering by a magnetic dot, whose average B vanishes, and show that the Hall and longitudinal resistivities, as a function of the Fermi energy, exhibit a pronounced oscillatory structure due to the presence of quasi-bound states. Depending on the dot parameters this oscillatory structure differs substantially for energies below and above the first Landau level.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000293008900002	Publication Date	2011-07-16
	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	38	Open Access
	Notes	; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE, the Canadian NSERC grant no. OGP0121756 and the Belgian Science Policy (IAP). We acknowledge discussions and correspondence with Professor A Matulis. ;			Approved	Most recent IF: 2.649; 2011 IF: 2.546
	Call Number	UA @ lucian @ c:irua:91176			Serial	1372
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	Author	Varley, J.B.; Peelaers, H.; Janotti, A.; van de Walle, C.G.
	Title	Hydrogenated cation vacancies in semiconducting oxides			Type	A1 Journal article
	Year	2011	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	23	Issue	33	Pages	334212,1-334212,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using first-principles calculations we have studied the electronic and structural properties of cation vacancies and their complexes with hydrogen impurities in SnO2, In2O3 and β-Ga2O3. We find that cation vacancies have high formation energies in SnO2 and In2O3 even in the most favorable conditions. Their formation energies are significantly lower in β-Ga2O3. Cation vacancies, which are compensating acceptors, strongly interact with H impurities resulting in complexes with low formation energies and large binding energies, stable up to temperatures over 730 °C. Our results indicate that hydrogen has beneficial effects on the conductivity of transparent conducting oxides: it increases the carrier concentration by acting as a donor in the form of isolated interstitials, and by passivating compensating acceptors such as cation vacancies; in addition, it potentially enhances carrier mobility by reducing the charge of negatively charged scattering centers. We have also computed vibrational frequencies associated with the isolated and complexed hydrogen, to aid in the microscopic identification of centers observed by vibrational spectroscopy.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000294060600014	Publication Date	2011-08-04
	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	125	Open Access
	Notes	; We gratefully acknowledge useful discussions with M D Mc-Cluskey, O Bierwagen and J Speck. The work was supported by the NSF MRSEC Program (DMR05-20415), the Flemish Science Foundation (FWO-VI), the Belgian American Educational Foundation, and by Saint-Gobain Research, and made use of computing facilities at CNSI (NSF grant No. CHE-0321368), TeraGrid and TACC (NSF grant No. DMR070072N), and NERSC (DOE Office of Science Contract No. DE-AC02-05CH11231). ;			Approved	Most recent IF: 2.649; 2011 IF: 2.546
	Call Number	UA @ lucian @ c:irua:92415			Serial	1534
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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.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	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	Gélard, J.; Jehanathan, N.; Roussel, H.; Gariglio, S.; Lebedev, O.I.; Van Tendeloo, G.; Dubourdieu, C.
	Title	Off-stoichiometry effects on the crystalline and defect structure of hexagonal manganite REMnO₃ films (RE = Y, Er, Dy)			Type	A1 Journal article
	Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	23	Issue	5	Pages	1232-1238
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The crystalline and defect structure of epitaxial hexagonal RExMnyO3 (RE = Er, Dy) films with varying cationic composition was investigated by X-ray diffraction and transmission electron microscopy. The films are composed of a strained layer at the interface with the substrate and of a relaxed layer on top of it. The critical thickness is of 10 to 25 nm. For Mn-rich films (or RE deficient), an off-stoichiometric composition maintaining the hexagonal LuMnO3-type structure is stabilized over a large range of the RE/Mn ratio (0.72−1.00), with no Mn-rich secondary phases observed. A linear dependence of the out-of-plane lattice parameter with RE/Mn is observed in this range. Out-of-phase boundary (OPB) extended defects are observed in all films and exhibit a local change in stoichiometry. Such a large solubility limit in the RE deficient region points toward the formation of vacancies on the RE site (RExMnO3−δ, with 0.72 ≤ x < 1), a phenomenon that is encountered in perovskite manganites such as LaxMnO3−δ (x < 1) and that may strongly impact the physical properties of hexagonal manganites.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000287767200022	Publication Date	2011-02-03
	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	17	Open Access
	Notes				Approved	Most recent IF: 9.466; 2011 IF: 7.286
	Call Number	UA @ lucian @ c:irua:88649			Serial	2430
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	Author	Dachraoui, W.; Yang, T.; Liu, C.; Ling, G.; Hadermann, J.; Van Tendeloo, G.; Llobet, A.; Greenblatt, M.
	Title	Short-range layered A-site ordering in double perovskites NaLaBB'O₆ (B = Mn, Fe; B' = Nb, Ta)			Type	A1 Journal article
	Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	23	Issue	9	Pages	2398-2406
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The new compounds NaLaFeTaO6, NaLaFeNbO6, NaLaMnTaO6, and NaLaMnNbO6 have been synthesized and characterized with a combination of transmission electron microscopy, X-ray powder diffraction (XRPD), neutron powder diffraction (NPD), and magnetization measurements. Through electron microscopy study, a local layered order of the A-cations has been detected without the typical occurrence of rock salt order at the B-cation site. Satellite reflections in the electron diffraction related to the local layered order are not visible on the XRPD or NPD patterns. The occurrence of local layered order is supported by pair distribution function analysis, which also reveals the presence of uncorrelated displacements of the Nb and Ta cations. The octahedra are tilted according to the system a−b+a−, and the coordinates were refined from XRPD and NPD with a disordered cation distribution in the space group Pnma. The magnetic exchange interactions in NaLaFeTaO6 and NaLaFeNbO6 are antiferromagnetic, while they are ferromagnetic in NaLaMnTaO6 and NaLaMnNbO6. Long-range magnetic ordering is not observed down to 4 K for any of the compositions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000290063600016	Publication Date	2011-04-14
	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	14	Open Access
	Notes	Esteem 026019			Approved	Most recent IF: 9.466; 2011 IF: 7.286
	Call Number	UA @ lucian @ c:irua:89944			Serial	2996
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	Author	Hadermann, J.; Abakumov, A.M.; Turner, S.; Hafideddine, Z.; Khasanova, N.R.; Antipov, E.V.; Van Tendeloo, G.
	Title	Solving the structure of Li ion battery materials with precession electron diffraction : application to Li₂CoPo₄F			Type	A1 Journal article
	Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	23	Issue	15	Pages	3540-3545
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The crystal structure of the Li2CoPO4F high-voltage cathode for Li ion rechargeable batteries has been completely solved from precession electron diffraction (PED) data, including the location of the Li atoms. The crystal structure consists of infinite chains of CoO4F2 octahedra sharing common edges and linked into a 3D framework by PO4 tetrahedra. The chains and phosphate anions together delimit tunnels filled with the Li atoms. This investigation demonstrates that PED can be successfully applied for obtaining structural information on a variety of Li-containing electrode materials even from single micrometer-sized crystallites.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000293357100019	Publication Date	2011-07-11
	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	46	Open Access
	Notes	Fwo; Bof			Approved	Most recent IF: 9.466; 2011 IF: 7.286
	Call Number	UA @ lucian @ c:irua:90357			Serial	3053
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	Author	Rusakov, D.; Abakumov, A.M.; Yamaura, K.; Belik, A.A.; Van Tendeloo, G.; Takayama-Muromachi, E.
	Title	Structural evolution of the BiFeO₃-LaFeO₃ system			Type	A1 Journal article
	Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	23	Issue	2	Pages	285-292
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The (1 − x)BiFeO3−xLaFeO3 system has been investigated and characterized by room-temperature and high-temperature laboratory and synchrotron powder X-ray diffraction, electron diffraction, high-resolution transmission electron microscopy, differential scanning calorimetry, and magnetization measurements. At room temperature, the ferroelectric R3c phase is observed for 0.0 ≤ x ≤ 0.10. The PbZrO3-related √2ap × 2√2ap × 4ap superstructure (where ap is the parameter of the cubic perovskite subcell) is observed for Bi0.82La0.18FeO3, while an incommensurately modulated phase is formed for 0.19 ≤ x ≤ 0.30 with the √2ap × 2ap × √2ap basic unit cell. The GdFeO3-type phase with space group Pnma (√2ap × 2ap × √2ap) is stable at 0.50 ≤ x ≤ 1. Bi0.82La0.18FeO3 has no detectable homogeneity range (space group Pnam, a = 5.6004(1) Å, b = 11.2493(3) Å, c = 15.6179(3) Å). The incommensurately modulated Bi0.75La0.25FeO3 structure was solved from synchrotron X-ray powder diffraction data (Imma(00γ)s00 superspace group, a = 5.5956(1) Å, b = 7.8171(1) Å, c = 5.62055(8) Å, q = 0.4855(4)c*, RP = 0.023, RwP = 0.033). In this structure, cooperative displacements of the Bi and O atoms occur, which order within the (AO) (where A = Bi, La) layers, resulting in an antipolar structure. Local fluctuations of the intralayer antipolar ordering are compensated by an interaction with the neighboring (AO) layers. A coupling of the antipolar displacements with the cooperative tilting distortion of the perovskite octahedral framework is proposed as the origin of the incommensurability. All the phases transform to the GdFeO3-type structure at high temperatures. Bi0.82La0.18FeO3 shows an intermediate PbZrO3-type phase with √2ap × 2√2ap × 2ap (space group Pbam; a = 5.6154(2) Å, b = 11.2710(4) Å, and c = 7.8248(2) Å at 570 K). The compounds in the compositional range of 0.18 ≤ x ≤ 0.95 are canted antiferromagnets.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000286160800021	Publication Date	2010-12-23
	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	133	Open Access
	Notes				Approved	Most recent IF: 9.466; 2011 IF: 7.286
	Call Number	UA @ lucian @ c:irua:88650			Serial	3236
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	Author	Hao, Y.L.; Djotyan, A.P.; Avetisyan, A.A.; Peeters, F.M.
	Title	D^- shallow donor near a semiconductor-metal and a semiconductor-dielectric interface			Type	A1 Journal article
	Year	2011	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	23	Issue	11	Pages	115303,1-115313,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The ground state energy and the extent of the wavefunction of a negatively charged donor (D − ) located near a semiconductormetal or a semiconductordielectric interface are obtained. We apply the effective mass approximation and use a variational two-electron wavefunction that takes into account the influence of all image charges that arise due to the presence of the interface, as well as the correlation between the two electrons bound to the donor. For a semiconductormetal interface, the D − binding energy is enhanced for donor positions d > 1.5aB (aB is the effective Bohr radius) due to the additional attraction of the electrons with their images. When the donor approaches the interface (i.e. d < 1.5aB) the D − binding energy drops and eventually it becomes unbound. For a semiconductordielectric (or a semiconductorvacuum) interface the D − binding energy is reduced for any donor position as compared to the bulk case and the system becomes rapidly unbound when the donor approaches the interface.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000287969200013	Publication Date	2011-03-04
	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	5	Open Access
	Notes	; This work was supported by the Belgian Science Policy (IAP) and the Brazilian Science Foundation CNPq. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (IAP). ;			Approved	Most recent IF: 2.649; 2011 IF: 2.546
	Call Number	UA @ lucian @ c:irua:88828			Serial	3528
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	Author	Eckert, M.; Mortet, V.; Zhang, L.; Neyts, E.; Verbeeck, J.; Haenen, ken; Bogaerts, A.
	Title	Theoretical investigation of grain size tuning during prolonged bias-enhanced nucleation			Type	A1 Journal article
	Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	23	Issue	6	Pages	1414-1423
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	In this paper, the effects of prolonged bias-enhanced nucleation (prolonged BEN) on the growth mechanisms of diamond are investigated by molecular dynamics (MD) and combined MD-Metropolis Monte Carlo (MD-MMC) simulations. First, cumulative impacts of CxHy+ and Hx+ on an a-C:H/nanodiamond composite were simulated; second, nonconsecutive impacts of the dominant ions were simulated in order to understand the observed phenomena in more detail. As stated in the existing literature, the growth of diamond structures during prolonged BEN is a process that takes place below the surface of the growing film. The investigation of the penetration behavior of CxHy+ and Hx+ species shows that the carbon-containing ions remain trapped within this amorphous phase where they dominate mechanisms like precipitation of sp3 carbon clusters. The H+ ions, however, penetrate into the crystalline phase at high bias voltages (>100 V), destroying the perfect diamond structure. The experimentally measured reduction of grain sizes at high bias voltage, reported in the literature, might thus be related to penetrating H+ ions. Furthermore, the CxHy+ ions are found to be the most efficient sputtering agents, preventing the build up of defective material.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000288291400011	Publication Date	2011-02-23
	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	9	Open Access
	Notes	Iwt; Fwo; Esteem 026019; Iap			Approved	Most recent IF: 9.466; 2011 IF: 7.286
	Call Number	UA @ lucian @ c:irua:87642			Serial	3605
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	Author	Idrissi, H.; Wang, B.; Colla, M.S.; Raskin, J.P.; Schryvers, D.; Pardoen, T.
	Title	Ultrahigh strain hardening in thin palladium films with nanoscale twins			Type	A1 Journal article
	Year	2011	Publication	Advanced materials	Abbreviated Journal	Adv Mater
	Volume	23	Issue	18	Pages	2119-2122
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Nanocrystalline Pd thin films containing coherent growth twin boundaries are deformed using on-chip nanomechanical testing. A large work-hardening capacity is measured. The origin of the observed behavior is unraveled using transmission electron microscopy and shows specific dislocations and twin boundaries interactions. The results indicate the potential for large strength and ductility balance enhancement in Pd films, as needed in membranes for H technologies.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000291164200013	Publication Date	2011-04-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0935-9648;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	19.791	Times cited	57	Open Access
	Notes	Iap			Approved	Most recent IF: 19.791; 2011 IF: 13.877
	Call Number	UA @ lucian @ c:irua:90103			Serial	3794
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	Author	Kazakov, S.M.; Abakumov, A.M.; Perz-Mato, J.M.; Ovchinnikov, A.V.; Roslova, M.V.; Boltalin, A.I.; Morozov, I.V.; Antipov, E.V.; Van Tendeloo, G.
	Title	Uniform patterns of Fe-vacancy ordering in the K_x(Fe,Co)_2-ySe₂ superconductors			Type	A1 Journal article
	Year	2011	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	23	Issue	19	Pages	4311-4316
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The Fe-vacancy ordering patterns in the superconducting KxFe2ySe2 and nonsuperconducting Kx(Fe,Co)2ySe2 samples have been investigated by electron diffraction and high angle annular dark field scanning transmission electron microscopy. The Fe-vacancy ordering occurs in the ab plane of the parent ThCr2Si2-type structure, demonstrating two types of patterns. Superstructure I retains the tetragonal symmetry and can be described with the aI = bI = as√5 (as is the unit cell parameter of the parent ThCr2Si2-type structure) supercell and I4/m space group. Superstructure II reduces the symmetry to orthorhombic with the aII = as√2, bII = 2as√2 supercell and the Ibam space group. This type of superstructure is observed for the first time in KxFe2ySe2. The Fe-vacancy ordering is inhomogeneous: the disordered areas interleave with the superstructures I and II in the same crystallite. The observed superstructures represent the compositionally dependent uniform ordering patterns of two species (the Fe atoms and vacancies) on a square lattice. More complex uniform ordered configurations, including compositional stripes, can be predicted for different chemical compositions of the KxFe2ySe2 (0 < y < 0.5) solid solutions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000295487800005	Publication Date	2011-09-13
	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	20	Open Access
	Notes				Approved	Most recent IF: 9.466; 2011 IF: 7.286
	Call Number	UA @ lucian @ c:irua:92805			Serial	3810
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	Author	Rakhimov, K.Y.; Chaves, A.; Farias, G.A.; Peeters, F.M.
	Title	Wavepacket scattering of Dirac and Schrödinger particles on potential and magnetic barriers			Type	A1 Journal article
	Year	2011	Publication	Journal of physics : condensed matter	Abbreviated Journal	J Phys-Condens Mat
	Volume	23	Issue	27	Pages	275801,1-275801,16
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We investigate the dynamics of a charged particle moving in a graphene layer and in a two-dimensional electron gas, where it obeys the Dirac and the Schrödinger equations, respectively. The charge carriers are described as Gaussian wavepackets. The dynamics of the wavepackets is studied numerically by solving both quantum-mechanical and relativistic equations of motion. The scattering of such wavepackets by step-like magnetic and potential barriers is analysed for different values of wavepacket energy and width. We find: (1) that the average position of the wavepacket does not coincide with the classical trajectory, and (2) that, for slanted incidence, the path of the centre of mass of the wavepacket does not have to penetrate the barrier during the scattering process. Trembling motion of the charged particle in graphene is observed in the absence of an external magnetic field and can be enhanced by a substrate-induced mass term.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000291993600009	Publication Date	2011-06-18
	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	32	Open Access
	Notes	; Discussions with A Matulis are gratefully acknowledged. KR is beneficiary of a mobility grant from the Belgian Federal Science Policy Office, co-funded by the European Commission and was supported in part by a grant of the Third World Academy of Sciences (ref. 09-188 RG/PHYS/AS-I). In addition, this work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the joint project CNPq-FWO, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ;			Approved	Most recent IF: 2.649; 2011 IF: 2.546
	Call Number	UA @ lucian @ c:irua:90880			Serial	3908
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	Author	Karapetrov, G.; Belkin, A.; Iavarone, M.; Fedor, J.; Novosad, V.; Milošević, M.V.; Peeters, F.M.
	Title	Anisotropic superconductivity and vortex dynamics in magnetically coupled F/S and F/S/F hybrids			Type	A1 Journal article
	Year	2011	Publication	Journal of superconductivity and novel magnetism	Abbreviated Journal	J Supercond Nov Magn
	Volume	24	Issue	1/2	Pages	905-910
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Magnetically coupled superconductorferromagnet hybrids offer advanced routes for nanoscale control of superconductivity. Magnetotransport characteristics and scanning tunneling microscopy images of vortex structures in superconductorferromagnet hybrids reveal rich superconducting phase diagrams. Focusing on a particular combination of a ferromagnet with a well-ordered periodic magnetic domain structure with alternating out-of-plane component of magnetization, and a small coherence length superconductor, we find directed nucleation of superconductivity above the domain wall boundaries. We show that near the superconductor-normal state phase boundary the superconductivity is localized in narrow mesoscopic channels. In order to explore the Abrikosov flux line ordering in F/S hybrids, we use a combination of scanning tunneling microscopy and GinzburgLandau simulations. The magnetic stripe domain structure induces periodic local magnetic induction in the superconductor, creating a series of pinninganti-pinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-1D arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes nonlinear due to a change in both the number of vortices and the confining potential. In F/S/F hybrids we demonstrate the evolution of the anisotropic conductivity in the superconductor that is magnetically coupled with two adjacent ferromagnetic layers. Stripe magnetic domain structures in both F-layers are aligned under each other, resulting in a directional superconducting order parameter in the superconducting layer. The conductance anisotropy strongly depends on the period of the magnetic domains and the strength of the local magnetization. The anisotropic conductivity of up to three orders of magnitude can be achieved with a spatial critical temperature modulation of 5% of T c. Induced anisotropic properties in the F/S and F/S/F hybrids have a potential for future application in switching and nonvolatile memory elements operating at low temperatures.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000289855700150	Publication Date	2010-10-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1557-1939;1557-1947;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.18	Times cited	2	Open Access
	Notes	; This work as well as the use of the Center for Nanoscale Materials and the Electron Microscopy Center at Argonne National Laboratory were supported by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. This work was also supported by the Ministry of Education, Agency for Structural Funds of the European Union, Research and Development Program, under agreement 262 401 200 19. M.V.M. and F. M. P. acknowledge support from the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, the JSPS/ESF-NES program, the ESF-AQDJJ network, and the Vlaanderen-USA bilateral program. ;			Approved	Most recent IF: 1.18; 2011 IF: 0.650
	Call Number	UA @ lucian @ c:irua:89930			Serial	130
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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
	Corporate Author				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
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	Author	Kapra, A.V.; Misko, V.R.; Vodolazov, D.Y.; Peeters, F.M.
	Title	The guidance of vortex-antivortex pairs by in-plane magnetic dipoles in a superconducting finite-size film			Type	A1 Journal article
	Year	2011	Publication	Superconductor science and technology	Abbreviated Journal	Supercond Sci Tech
	Volume	24	Issue	2	Pages	024014-024014,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The possibility of manipulating vortex matter by using various artificial pinning arrays is of significant importance for possible applications in nano and micro fluxonics devices. By numerically solving the time-dependent GinzburgLandau equations, we study the vortexantivortex (vav) dynamics in a hybrid structure consisting of a finite-size superconductor with magnetic dipoles on top which generate vav pairs in the presence of an external current. The vav dynamics is analyzed for different arrangements and magnetic moments of the dipoles, as a function of angle α between the direction of the magnetic dipole and that of the Lorentz force produced by the applied current. The interplay of the attractive interaction between a vav pair and the Lorentz force leads either to the separation of (anti)vortices and their motion in opposite directions or to their annihilation. We found a critical angle αc, below which vortices and antivortices are repelled, while for larger angles they annihilate. In case of a single (few) magnetic dipole(s), this magnetic dipole induced vav guidance is influenced by the self-interaction of the vav pairs with their images in a finite-size sample, while for a periodic array of dipoles the guidance is determined by the interaction of a vav pair with other dipoles and vav pairs created by them. This effect is tunable through the external current and the magnetization and size of the magnetic dipoles.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000286379900015	Publication Date	2011-01-20
	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	28	Open Access
	Notes	; This work was supported by the 'Odysseus' program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-Vl. DYV acknowledges support from the Russian Fund for Basic Research and Russian Agency of Education under the Federal Programme 'Scientific and educational personnel of innovative Russia in 2009-2013'. ;			Approved	Most recent IF: 2.878; 2011 IF: 2.662
	Call Number	UA @ lucian @ c:irua:88732			Serial	1399
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	Author	Milošević, M.V.; Peeters, F.M.; Jankó, B.
	Title	Vortex manipulation in superconducting films with tunable magnetic topology			Type	A1 Journal article
	Year	2011	Publication	Superconductor science and technology	Abbreviated Journal	Supercond Sci Tech
	Volume	24	Issue	2	Pages	024001-024001,6
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using a combination of the phenomenological GinzburgLandau theory and micromagnetic simulations, we study properties of a superconducting film with an array of soft magnetic dots on top. An external in-plane magnetic field gradually drives the magnets from an out-of-plane or magnetic vortex state to an in-plane single-domain state, which changes spatially the distribution of the superconducting condensate. If induced by the magnets, the vortexantivortex molecules exhibit rich transitions as a function of the applied in-plane field. At the same time, we show how the magnetic dots act as very effective dynamic pinning centers for vortices in an applied perpendicular magnetic field.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000286379900002	Publication Date	2011-01-20
	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	8	Open Access
	Notes	; This research was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the JSPS/ESF-NES program, the bilateral project between Flanders and the USA, NSF NIRT, ECS-0609249, and the Institute for Theoretical Sciences. ;			Approved	Most recent IF: 2.878; 2011 IF: 2.662
	Call Number	UA @ lucian @ c:irua:88731			Serial	3870
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	Author	Düking, R.; Gielis, J.; Liese, W.
	Title	Carbon flux and carbon stock in a bamboo stand and their relevance for mitigating climate change			Type	A3 Journal article
	Year	2011	Publication	Bamboo Science & Culture	Abbreviated Journal
	Volume	24	Issue	1	Pages	1-6
	Keywords	A3 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	In this report we describe the basics of biological carbon fixation in bamboo forests. Confusing carbon stock with carbon flux has led to false expectations on the significance of bamboo forests as carbon sinks. Furthermore, misunderstandings about the growth of bamboo culms can lead to highly exaggerated expectations on the productivity of bamboo.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1535-7635	ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:91091			Serial	7578
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	Author	Čevik, U.; Damla, N.; Van Grieken, R.; Vefa Akpinar, M.
	Title	Chemical composition of building materials used in Turkey			Type	A1 Journal article
	Year	2011	Publication	Construction and building materials	Abbreviated Journal
	Volume	25	Issue	4	Pages	1546-1552
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The main goal of this work was to determine the chemical composition of building materials used in Turkey by utilizing energy dispersive X-ray fluorescence (EDXRF) spectrometry. Gas concrete, cement, sand, bricks, roofing tiles, marble, lime and gypsum materials were selected as building materials for this research. The chemical contents and their trace concentrations of the selected samples were determined. The most abundant oxides measured were generally SiO2, Al2O3, CaO, MgO, Fe2O3, K2O and SO3 for all samples. While the main chemical component of gas concrete, cement, sand and marble samples were SiO2 and CaO, brick and roofing tile mainly consisted of SiO2 and Al2O3. CaO and SO3 were major component of lime and gypsum samples, respectively. For U and Th concentrations in the samples, activities of 226Ra and 232Th were measured by utilizing gamma spectrometry. ANOVA and Pearson correlation analyses were performed on the studied data for statistical analysis.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000287379300007	Publication Date	2010-09-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0950-0618	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:86448			Serial	7653
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	Author	Afanasov, I.M.; Lebedev, O.I.; Kolozhvary, B.A.; Smirnov, A.V.,; Van Tendeloo, G.
	Title	Nickel/carbon composite materials based on expanded graphite			Type	A1 Journal article
	Year	2011	Publication	New carbon materials	Abbreviated Journal
	Volume	26	Issue	5	Pages	335-340
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Monolithic nickel/carbon (Ni/C) composites were prepared from coal tar pitch-impregnated compressed expanded graphite pre-decorated with NiO particles (EGNiO) by pyrolysis at 550 °C and subsequent steam activation at 800 °C. The microstructural arrangement of the Ni-comprising nanoparticles in the composites was investigated using transmission electron microscopy. The specific surface area and porosity of the composites were analyzed by nitrogen adsorption. The catalytic activity of the composites was compared with the material obtained by the conventional H2 treatment of EGNiO using hydrocracking of 2,2,3-trimethylpentane as a model reaction.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000296926500003	Publication Date	2011-11-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1872-5805;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	7	Open Access
	Notes	Iap			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:93633			Serial	2340
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	Author	Simon, P.; Bogaerts, A.
	Title	Vibrational level population of nitrogen impurities in low-pressure argon glow discharges			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	4	Pages	804-810
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	The vibrational level populations of the electronic ground state of the nitrogen molecule have been calculated for typical glow discharge conditions in argonnitrogen mixtures with nitrogen concentrations between 0.1 and 1%. Stationary solutions of the master equations of the vibrational levels have been obtained using numerical methods. The main mechanisms responsible for the population and depopulation of the vibrational levels, and for the overall shape of the vibrational distribution function are pointed out. It has been found that vibrationvibration collisions play only a minor role and therefore the population of the vibrational levels is basically determined by the electron temperature.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000288703300012	Publication Date	2010-12-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477;1364-5544;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	6	Open Access
	Notes				Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ lucian @ c:irua:87530			Serial	3842
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	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	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	Rouchon, V.; Pellizzi, E.; Duranton, M.; Vanmeert, F.; Janssens, K.
	Title	Combining XANES, ICP-AES, and SEM/EDS for the study of phytate chelating treatments used on iron gall ink damaged manuscripts			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	12	Pages	2434-2441
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Many historical documents written with iron gall inks are endangered by the corrosive effects of these inks. In this work, a combination of complementary analytical methods was used for the first time in order to study the phytate process which is used in conservation studios to stabilize damaged manuscripts. This process consists of an antioxidant treatment performed by means of a calcium phytate (CP) solution, followed by a deacidification treatment performed with a calcium carbonate (CC) solution. The antioxidant treatment capitalizes on the properties of myo-inositol hexaphosphoric acid (phytic acid) that inhibits iron through chelation. In order to use relatively low acidic solutions, the pH of the CP solution is increased up to values between 5 and 6, which is in the range of the CP precipitation threshold. This study was performed on laboratory samples made of paper impregnated with iron gall ink and artificially aged in climatic chambers. It aims to investigate how the CP precipitate impacts the efficiency of the treatment. Side effects, such as elemental losses and deposits, were measured by means of several analytical techniques (FeK Edge XANES, SEM/EDS, and ICP-AES). These measurements were crosschecked with a ready to use colour spot test made of bathophenanthroline impregnated paper. It appeared that the CP treatment should necessarily be followed by the deacidification treatment in order to achieve long term stability. The precipitation of CP in the treating solution does finally not impact the efficiency of the treatment despite the fact that it should theoretically lower the availability of phytate to chelate iron. A scenario is proposed to explain this point.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000297030400008	Publication Date	2011-10-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	10	Open Access
	Notes	; This research was funded by SOLEIL (proposals 20060396 and 20080761) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. We are thankful to the paper conservator students of the Institut National du Patrimoine who were involved in some of the sample preparations, and to Dr Dominique Thiaudiere and Dr Solenn Reguer for their assistance and help during the experiments performed at SOLEIL beamline “DIFFABS”. ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:93845			Serial	5527
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	Author	Cagno, S.; Nuyts, G.; Bugani, S.; De Vis, K.; Schalm, O.; Caen, J.; Helfen, L.; Cotte, M.; Reischig, P.; Janssens, K.
	Title	Evaluation of manganese-bodies removal in historical stained glass windows via SR-\mu-XANES/XRF and SR-\mu-CT			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	12	Pages	2442-2451
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	The speed and effectiveness of a conservation treatment used for stained glass windows have been investigated. Dark-coloured Mn-rich stains can be found in the alteration layer of ancient glass artefacts and cause the surface to turn brown/black: this phenomenon is known as Mn-browning or Mn-staining. While in glass manganese is present in the +II or +III oxidation states, in the Mn-rich bodies, manganese is in a higher oxidation state (+IV). In restoration practice, mildly reducing solutions are employed to eliminate the dark colour and restore the clear appearance of the glass. In this paper the effectiveness and side effects of the use of hydroxylamine hydrochloride for this purpose are assessed. Archaeological fragments of stained glass windows, dated to the 14th century and originating from Sidney Sussex College, Cambridge (UK), were examined by means of synchrotron radiation (SR) based microscopic X-ray Absorption Near-Edge Spectroscopy (μ-XANES) and microscopic X-Ray Fluorescence (μ-XRF) and with high resolution computed absorption tomography (μ-CT) before, during and after the treatment. The monitoring of the glass fragments during the treatment allows us to better understand the manner in which the process unfolds and its kinetics. The results obtained reveal that the hydroxylamine hydrochloride treatment is effective, but also that it has a number of unwanted side effects. These findings are useful for optimizing the time and other modalities of the Mn-reducing treatment as well as minimizing its unwanted results.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000297030400009	Publication Date	2011-10-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	17	Open Access
	Notes	; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. Special thanks to Ms Leonie Seliger, head of the stained-glass conservation studio (The Cathedral Studios-The Chapter of Canterbury Cathedral) for the supply of the archaeological samples. The authors gratefully acknowledge ESRF for granting beamtime (proposal EC-602). ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:93848			Serial	5613
Permanent link to this record



	Author	de Nolf, W.; Dik, J.; van der Snickt, G.; Wallert, A.; Janssens, K.
	Title	High energy X-ray powder diffraction for the imaging of (hidden) paintings			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	5	Pages	910-916
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Over the past few years a number of innovative imaging techniques have been introduced for the visualization of hidden paint layers in Old Master Paintings. These include X-ray fluorescence scanning, TeraHertz imaging, optical coherence tomography and other acoustics-based forms of visualization. All of these techniques are usually a trade-off between their penetrative capability on the one side and their analytical precision in terms of spatial resolution and material identification on the other. Here, we present the first-time use of High-Energy X-ray Powder Diffraction imaging (HE-XRPD) in the study of hidden layers in paintings. As an imaging tool, it combines high-depth sensitivity with fingerprint identification of most inorganic painting materials. The potential as well as some limitations of this technique are demonstrated using model paintings as well as an authentic 16th century painting.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000289731900005	Publication Date	2011-03-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	34	Open Access
	Notes	; ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:89922			Serial	5640
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	Author	van der Snickt, G.; Miliani, C.; Janssens, K.; Brunetti, B.G.; Romani, A.; Rosi, F.; Walter, P.; Castaing, J.; de Nolf, W.; Klaassen, L.; Labarque, I.; Wittermann, R.
	Title	Material analyses of “Christ with singing and music-making Angels”, a late 15th-C panel painting attributed to Hans Memling and assistants : part 1 : non-invasive in situ investigations			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	11	Pages	2216-2229
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In cultural heritage science, compositional data is traditionally obtained from works of art through the analysis of samples by means of various bench-top instruments (scanning electron microscope, Raman spectrometer, etc.). Alternatively, the object can be transported to a laboratory where it may be examined, usually by spectroscopic methods working in reflection mode. However, this paper describes how a complementary set of mobile and portable instruments was deployed in situ to gain a comprehensive view on the materials and related ageing compounds of an (almost) unmovable 15th-C polyptych, prior to and in preparation of the extraction of a limited number of samples. In line with the methodological approach discussed, PXRF was first employed as an efficient screening tool. The ensuing elemental data was supplemented by more specific information on both organic as inorganic materials supplied by reflection near- and mid-FTIR spectroscopy and fluorimetry. In completion, a limited number of diffraction patterns were collected with a mobile XRD instrument in order to identify the constituent crystalline phases in pigments, grounding materials and degradation products. In this way, it could be demonstrated how a rich array of colours was obtained by means of a limited palette of pigments: lead white, lead tin yellow, azurite, natural ultramarine, bone black, vermillion, madder lake, and a green copper-organo complex were detected and situated on the panels. Remarkably, next to chalk also gypsum was found in the ground layer(s) of this Western European easel painting. The relatively large surface of the background was covered with gold leaf; the analyses seem to point towards the labour-intensive water gilding technique. The versatility of this combination of analytical techniques was further illustrated by the accurate characterisation of degradation products affecting the readability and conservation of the painting: the overall presence of a calcium oxalate-based film of variable thickness was established. Nevertheless, further analysis of cross-sectioned samples was considered desirable in order to study the stratigraphy, to gain direct access to altered and sub-imposed layers and to allow highly detailed analysis of micrometric degradation products by state-of-the art techniques (i.e. synchrotron radiation).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000296021800010	Publication Date	2011-09-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	32	Open Access
	Notes	; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0103.04, G.0689.06 and G.0704.08. The staff of the Royal Museum of Fine Arts Antwerp is acknowledged for this pleasant cooperation and the authorisation for the publication of the images in this article. Therefore, a word of gratitude to Paul Huvenne, Yolande Deckers, Stef Antonissen and Gwen Borms. In addition, the authors would like to thank the MOLAB's team operators Chiari Anselmi and Federica Presciutti. MOLAB analyses have been carried out through the support of the EU within the 6th Framework Programme (Contract Eu-ARTECH, RII3-CT-2004-506171). ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:93680			Serial	5705
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	Author	Alfeld, M.; Janssens, K.; Dik, J.; de Nolf, W.; van der Snickt, G.
	Title	Optimization of mobile scanning macro-XRF systems for the in situ investigation of historical paintings			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	5	Pages	899-909
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Elemental distribution maps are of great interest in the study of historical paintings, as they allow to investigate the pigment use of the artist, to image changes made in the painting during or after its creation and in some cases to reveal discarded paintings that were later over painted. Yet a method that allows to record such maps of a broad range of elements in a fast, non-destructive and in situ manner is not yet commonly available; a dedicated mobile scanning XRF instrument might fill this gap. In this paper we present three self-built scanning macro-XRF instruments, each based on the experience gained with its precursor. These instruments are compared in terms of sensitivity and limits of detection, which includes a discussion of the use of polycapillary optics and pinhole collimators as beam defining devices. Furthermore, the imaging capabilities of the instruments are demonstrated in three exemplary cases: (parts of) historical paintings from the 15th to the 19th century are examined. These cases illustrate the value of element specific distribution maps in the study of historical paintings and allow in the case of Vincent van Gogh's Patch of Grass a direct comparison between in situ and synchrotron based scanning macro-XRF.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000289731900004	Publication Date	2011-03-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	107	Open Access
	Notes	; The investigation of the “Triptych of the Seven Sacraments'' was done in collaboration with Griet Steyaert, independent restorer, and Lizet Klaassen, Royal Museum of Fine Arts (Antwerp, Belgium). The investigation of ”Patch of Grass'' was realized in collaboration with Luuk van der Loeff, Kroller-Muller-Museum (Otterlo, The Netherlands). M. Alfeld is a PhD fellowship of the Research Foundation-Flanders (FWO). This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16) NACHO. The text also presents results of GOA "XANES meets ELNES'' (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0103.04, G.0689.06 and G.0704.08. Further, the work presented was sponsored by the Innovational Research Incentives Scheme of the Netherlands Organization for Scientific Research, NWO (proj. no. 016.118.303). ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:89919			Serial	5758
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	Author	Janssens, K.
	Title	Synchrotron radiation in art and archaeology			Type	Editorial
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	5	Pages	883-884
	Keywords	Editorial; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000289731900001	Publication Date	2011-04-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	5	Open Access
	Notes	; ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:89918			Serial	5864
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	Author	Radepont, M.; de Nolf, W.; Janssens, K.; van der Snickt, G.; Coquinot, Y.; Klaassen, L.; Cotte, M.
	Title	The use of microscopic X-ray diffraction for the study of HgS and its degradation products corderoite (\alpha-Hg₃S₂Cl₂), kenhsuite (\gamma-Hg₃S₂Cl₂) and calomel (Hg₂Cl₂) in historical paintings			Type	A1 Journal article
	Year	2011	Publication	Journal of analytical atomic spectrometry	Abbreviated Journal	J Anal Atom Spectrom
	Volume	26	Issue	5	Pages	959-968
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	Since antiquity, the red pigment mercury sulfide (α-HgS), called cinnabar in its natural form or vermilion red when synthetic, was very often used in frescoes and paintings, even if it was known to suffer occasionally from degradation. The paint hereby acquires a black or silver-grey aspect. The chemical characterization of these alteration products is rather challenging mainly because of the micrometric size and heterogeneity of the surface layers that develop and that are responsible for the color change. Methods such as electron microscopy, synchrotron-based microscopic X-ray fluorescence, microscopic X-ray absorption near edge spectroscopy, Raman microscopy and secondary ion microscopy have been previously employed to identify the (Hg- and S-) compounds present and to study their co-localization. Next to these, also microscopic X-ray diffraction (XRD) (either by making use of laboratory X-ray sources or when used at a synchrotron facility) allows the identification of the crystal phases that are present in degraded HgS paint layers. In this paper we employ these various forms of micro-XRD to analyze degraded red paint in different paintings and compare the results with other X-ray based methods. Whereas the elemental analyses of the degradation products revealed, next to mercury and sulfur, the presence of chlorine, X-ray diffraction allowed the identification, next to α-HgS, of the Hg and S-containing compound calomel (Hg2Cl2) but also of the Hg, S and Cl-containing minerals corderoite (α-Hg3S2Cl2) and kenhsuite (γ-Hg3S2Cl2). These observations are consistent with X-ray absorption spectroscopy measurements performed at the S- and Cl-edges.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000289731900011	Publication Date	2011-03-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0267-9477	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.379	Times cited	40	Open Access
	Notes	; The authors gratefully acknowledge GOA programme “XANES meets EELS'' (University of Antwerp Research Council), the IUAP VI/P16 programme ”Nacho'' (BELSPO, Brussels, Belgium) and FWO (Brussels, Belgium) projects no. G.0689.06, G.0704.08 and G017909N for financial support, the ESRF for granting beamtime under proposals no. EC442 and EC720, and Gema Martinez-Criado for practical help on ID18F. The KMSKA staff is also gratefully acknowledged for their help and interest. Javier Chillida is thanked for providing us with the Pedralbes samples. The authors are also indebted to the CHARISMA project (grant agreement 228330) for financial support. ;			Approved	Most recent IF: 3.379; 2011 IF: 3.220
	Call Number	UA @ admin @ c:irua:89927			Serial	5896
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	Author	Cools, J.; Broekx, S.; Vandenberghe, V.; Seuntjens, P.; e.a.
	Title	Coupling a hydrological water quality model and an economic optimization model to set up a cost-effective emission reduction scenario for nitrogen			Type	A1 Journal article
	Year	2011	Publication	Environmental modelling and software	Abbreviated Journal
	Volume	26	Issue	1	Pages	44-51
	Keywords	A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
	Abstract	A modelling approach is presented that determines the most cost-effective set of reduction measures to reach an in-stream concentration target. The framework is based on the coupling of two models: the hydrological water quality model SWAT and an economic optimization model (Environmental Costing Model, ECM). SWAT is used to determine the relationship between the modelled in-stream concentration at the river basin outlet and the associated emission reduction. The ECM is used to set up marginal abatement cost curves for nutrients and oxygen demanding substances. Results for nitrogen are presented for the Grote Nete river basin in Belgium for the year 2006. Results show that the good status for total nitrogen can be reached in the study area. The most cost-effective measures are more productive dairy cattle, implementing basic measures as defined in the WFD, winter cover crops, improved efficiency of WWTP, enhanced fodder efficiency for pigs, further treatment of industrial waste water and tuned fertilization. (C) 2010 Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000283891600007	Publication Date	2010-05-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1364-8152	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:95529			Serial	7740
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