NANOlab Center of Excellence literature database -- Query Results

	NANOlab Center of Excellence literature database Home \| Show All \| Simple Search \| Advanced Search	Login Quick Search: Field: contains: ...
	211–240 of 259 records found matching your query (RSS \| history):

Select All Deselect All

<< 1 2 3 4 5 6 7 8 9 >>

List View

Citations

Details

	Records
	Author	Werner, R.; Raisch, C.; Leca, V.; Ion, V.; Bals, S.; Van Tendeloo, G.; Chasse, T.; Kleiner, R.; Koelle, D.
	Title	Transport, magnetic, and structural properties of La_0.7Ce_0.3MnO₃ thin films: evidence for hole-doping			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	79	Issue	5	Pages	054416,1-054416,8
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Cerium-doped manganite thin films were grown epitaxially by pulsed laser deposition at 720 °C and oxygen pressure pO2=125 Pa and were subjected to different annealing steps. According to x-ray diffraction (XRD) data, the formation of CeO2 as a secondary phase could be avoided for pO28 Pa. However, transmission electron microscopy shows the presence of CeO2 nanoclusters even in those films which appear to be single phase in XRD. With O2 annealing, the metal-to-insulator transition temperature increases, while the saturation magnetization decreases and stays well below the theoretical value for electron-doped La0.7Ce0.3MnO3 with mixed Mn3+/Mn2+ valences. The same trend is observed with decreasing film thickness from 100 to 20 nm, indicating a higher oxygen content for thinner films. Hall measurements on a film which shows a metal-to-insulator transition clearly reveal holes as dominating charge carriers. Combining data from x-ray photoemission spectroscopy, for determination of the oxygen content, and x-ray absorption spectroscopy (XAS), for determination of the hole concentration and cation valences, we find that with increasing oxygen content the hole concentration increases and Mn valences are shifted from 2+ to 4+. The dominating Mn valences in the films are Mn3+ and Mn4+, and only a small amount of Mn2+ ions can be observed by XAS. Mn2+ and Ce4+ XAS signals obtained in surface-sensitive total electron yield mode are strongly reduced in the bulk-sensitive fluorescence mode, which indicates hole-doping in the bulk for those films which do show a metal-to-insulator transition.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000263815400057	Publication Date	2009-02-13
	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	25	Open Access
	Notes	Esteem 026019; Fwo			Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:76221			Serial	3725
Permanent link to this record



	Author	Bending, S.J.; Neal, J.S.; Milošević, M.V.; Potenza, A.; san Emeterio, L.; Marrows, C.H.
	Title	Vortex-antivortex 'molecular crystals' in hybrid ferromagnet/superconductor structures			Type	A1 Journal article
	Year	2009	Publication	Journal of physics : conference series	Abbreviated Journal
	Volume	150	Issue	5	Pages	052019
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We have used high resolution Hall probe microscopy to image vortex-antivortex (V-AV) 'molecules' induced in superconducting Pb films by the stray fields from square arrays of ferromagnetic Co/Pt dots. We have directly observed spontaneous V-AV pairs and studied how they interact with added 'free' (anti)fluxons in an applied magnetic field. We observe a rich variety of subtle phenomena arising from competing symmetries in our system which can either drive added antivortices to join AV shells around nanomagnets or stabilise the translationally symmetric AV lattice between the dots. Added vortices annihilate AV shells, leading eventually to a stable 'nulling' state with no free fluxons, which should exhibit a strongly (field-)enhanced critical current. At higher densities we actually observe vortex shells around the magnets, stabilised by the asymmetric anti-pinning potential. Our experimental findings are in good agreement with Ginzburg-Landau calculations.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos		Publication Date	2009-04-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1742-6588;1742-6596;	ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:106136			Serial	3855
Permanent link to this record



	Author	Connolly, M.R.; Milošević, M.V.; Bending, S.J.; Clem, J.R.; Tamegai, T.
	Title	Vortex 'puddles' and magic vortex numbers in mesoscopic superconducting disks			Type	A1 Journal article
	Year	2009	Publication	Journal of physics : conference series	Abbreviated Journal
	Volume	150	Issue	5	Pages	052039
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The magnetic properties of a superconducting disk change dramatically when its dimensions become mesoscopic. Unlike large disks, where the screening currents induced by an applied magnetic field are strong enough to force vortices to accumulate in a 'puddle' at the centre, in a mesoscopic disk the interaction between one of these vortices and the edge currents can be comparable to the intervortex repulsion, resulting in a destruction of the ordered triangular vortex lattice structure at the centre. Vortices instead form clusters which adopt polygonal and shell-like structures which exhibit magic number states similar to those of charged particles in a confining potential, and electrons in artificial atoms. We have fabricated mesoscopic high temperature superconducting Bi2Sr2CaCu2O8+δ disks and investigated their magnetic properties using magneto-optical imaging (MOI) and high resolution scanning Hall probe microscopy (SHPM). The temperature dependence of the vortex penetration field measured using MOI is in excellent agreement with models of the thermal excitation of pancake vortices over edge barriers. The growth of the central vortex puddle has been directly imaged using SHPM and magic vortex numbers showing higher stability have been correlated with abrupt jumps in the measured local magnetisation curves.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos		Publication Date	2009-04-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1742-6588;1742-6596;	ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:106137			Serial	3881
Permanent link to this record



	Author	van der Linden, V.; Cosyns, P.; Schalm, O.; Cagno, S.; Nys, K.; Janssens, K.; Nowak, A.; Wagner, B.; Bulska, E.
	Title	Deeply coloured and black glass in the Northern provinces of the Roman Empire : differences and similarities in chemical composition before and after AD 150			Type	A1 Journal article
	Year	2009	Publication	Archaeometry	Abbreviated Journal	Archaeometry
	Volume	51	Issue	5	Pages	822-844
	Keywords	A1 Journal article; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In this work we attempt to elucidate the chronological and geographical origin of deeply coloured and black glass dating between 100 bc and ad 300 on the basis of their major and trace element compositions. Samples from the western and eastern parts of the Roman Empire were analysed. Analytical data were obtained by means of a scanning electron microscope – energy-dispersive system (SEM-EDS, 63 samples analysed) and laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS, 41 samples analysed). Among the glass fragments analysed, dark brown, dark purple and dark green hues could be distinguished. Only among the dark green fragments could a clear compositional distinction be observed between fragments dated to the periods before and after ad 150. In the early samples (first century bc to first century ad), iron, responsible for the green hue, was introduced by using impure sand containing relatively high amounts of Ti. In contrast, a Ti-poor source of iron was employed, containing Sb, Co and Pb in trace quantities, in order to obtain the dark green colour in the later glass samples. The analytical results obtained by combining SEM-EDS and LA-ICP-MS are therefore consistent with a differentiation of glassmaking recipes, detectable in glass composition, occurring in the period around ad 150.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000269728600009	Publication Date	2008-11-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-813x; 1475-4754	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.47	Times cited	39	Open Access
	Notes				Approved	Most recent IF: 1.47; 2009 IF: 1.355
	Call Number	UA @ admin @ c:irua:94510			Serial	5568
Permanent link to this record



	Author	Avetisyan, A.A.; Ghazaryan, A.V.; Djotyan, A.P.; Kirakosyan, A.A.; Moulopoulos, K.
	Title	Magnetoexcitons in semiconductor quantum rings with complicated (Kane's) dispersion law			Type	A1 Journal article
	Year	2009	Publication	Acta physica Polonica: A: general physics, solid state physics, applied physics T2 – 4th Workshop on Quantum Chaos and Localisation Phenomena, MAY 22-24, 2009, Polish Acad Sci, Ctr Theoret Phys, Inst Phys, Polish Acad Sci, Ctr Theoret Phys, Inst Phys, War	Abbreviated Journal
	Volume	116	Issue	5	Pages	826-828
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The influence of the nonparabolicity of charge carriers dispersion law (Kane's dispersion) on a magnetoexciton energy spectrum in InSb quantum rings is theoretically investigated The analytical expression for the energy spectrum of exciton in a narrow-gap semiconductor nanoring in a magnetic field is obtained. The Aharonov – Bohm oscillations in the energy of excited states are studied.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000273091200015	Publication Date	2016-02-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0587-4246	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:172293			Serial	8193
Permanent link to this record



	Author	Baltas, H.; Čevik, U.
	Title	Variation of K X-ray fluorescence cross-sections of Cu, Y and Ba in YBa₂Cu₃O_7-\delta superconductor			Type	A1 Journal article
	Year	2009	Publication	Solid state communications	Abbreviated Journal
	Volume	149	Issue	5/6	Pages	231-235
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	K X-ray fluorescence cross-sections of Cu, Y and Ba elements were measured in CuO, Y(2)O(3), BaCO(3) Compounds and YBa(2)Cu(3)O(7-delta) superconductor samples (nonreacted agent, calcined and sintered states). A superconductor sample of YBa(2)Cu(3)O(7-delta) was prepared by using a solid-state reaction technique. The samples were excited by gamma rays of energy 59.5 keV from a (241)Am radioisotope source. The Cu, Y and Ba K X-ray intensities counted with a Si(Li) detector were measured in different solid-state conditions. The obtained values of K X-ray fluorescence cross-section were compared with the theoretical values of pure Cu, Y and Ba elements. We found that the K X-ray fluorescence cross-section of Cu, Y and Ba in YBa(2)Cu(3)O(7-delta) sample is changed in different solid-state conditions, depending on the mixture (nonreacted agent), calcined and sintered states. (c) 2008 Elsevier Ltd. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000262795900013	Publication Date	2008-11-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0038-1098	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:94568			Serial	8735
Permanent link to this record



	Author	Batenburg, K.J.; Bals, S.; Sijbers, J.; Kübel, C.; Midgley, P.A.; Hernandez, J.C.; Kaiser, U.; Encina, E.R.; Coronado, E.A.; Van Tendeloo, G.
	Title	3D imaging of nanomaterials by discrete tomography			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	6	Pages	730-740
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	The field of discrete tomography focuses on the reconstruction of samples that consist of only a few different materials. Ideally, a three-dimensional (3D) reconstruction of such a sample should contain only one grey level for each of the compositions in the sample. By exploiting this property in the reconstruction algorithm, either the quality of the reconstruction can be improved significantly, or the number of required projection images can be reduced. The discrete reconstruction typically contains fewer artifacts and does not have to be segmented, as it already contains one grey level for each composition. Recently, a new algorithm, called discrete algebraic reconstruction technique (DART), has been proposed that can be used effectively on experimental electron tomography datasets. In this paper, we propose discrete tomography as a general reconstruction method for electron tomography in materials science. We describe the basic principles of DART and show that it can be applied successfully to three different types of samples, consisting of embedded ErSi2 nanocrystals, a carbon nanotube grown from a catalyst particle and a single gold nanoparticle, respectively.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000265816400005	Publication Date	2009-02-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-3991;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.843	Times cited	220	Open Access
	Notes	Fwo; Esteem 026019			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:74665 c:irua:74665			Serial	12
Permanent link to this record



	Author	Doenen, M.; Zhang, L.; Erni, R.; Williams, O.A.; Hardy, A.; van Bael, M.K.; Wagner, P.; Haenen, K.; Nesladek, M.; Van Tendeloo, G.
	Title	Diamond nucleation by carbon transport from buried nanodiamond TiO₂ sol-gel composites			Type	A1 Journal article
	Year	2009	Publication	Advanced materials	Abbreviated Journal	Adv Mater
	Volume	21	Issue	6	Pages	670-673
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000263492000007	Publication Date	2008-12-02
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0935-9648;1521-4095;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	19.791	Times cited	20	Open Access
	Notes	Fwo; Iap-P6/42; Esteem 026019			Approved	Most recent IF: 19.791; 2009 IF: NA
	Call Number	UA @ lucian @ c:irua:76329			Serial	688
Permanent link to this record



	Author	Bach, D.; Schneider, R.; Gerthsen, D.; Verbeeck, J.; Sigle, W.
	Title	EELS of niobium and stoichiometric niobium-oxide phases: part 1: plasmon and Near-edges fine structure			Type	A1 Journal article
	Year	2009	Publication	Microscopy and microanalysis	Abbreviated Journal	Microsc Microanal
	Volume	15	Issue	6	Pages	505-523
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A comprehensive electron energy-loss spectroscopy study of niobium (Nb) and stable Nb-oxide phases (NbO, NbO2, Nb2O5) was carried out. In this work (Part I), the plasmons and energy-loss near-edge structures (ELNES) of all relevant Nb edges (Nb-N2,3, Nb-M4,5, Nb-M2,3, Nb-M1, and Nb-L2,3) up to energy losses of about 2600 eV and the O-K edge are analyzed with respect to achieving characteristic fingerprints of Nb in different formal oxidation states (0 for metallic Nb, +2 for NbO, +4 for NbO2, and +5 for Nb2O5). Chemical shifts of the Nb-N2,3, Nb-M4,5, Nb-M2,3, and Nb-L2,3 edges are extracted from the spectra that amount to about 4 eV as the oxidation state increases from 0 for Nb to +5 for Nb2O5. Four different microscopes, including a 200 keV ZEISS Libra with monochromator, were used. The corresponding wide range of experimental parameters with respect to the primary electron energy, convergence, and collection semi-angles as well as energy resolution allows an assessment of the influence of the experimental setup on the ELNES of the different edges. Finally, the intensity of the Nb-L2,3 white-line edges is correlated with niobium 4d-state occupancy in the different reference materials.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge, Mass.	Editor
	Language		Wos	000272433200005	Publication Date	2009-10-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1431-9276;1435-8115;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.891	Times cited	55	Open Access
	Notes				Approved	Most recent IF: 1.891; 2009 IF: 3.035
	Call Number	UA @ lucian @ c:irua:80320UA @ admin @ c:irua:80320			Serial	790
Permanent link to this record



	Author	Berdiyorov, G.R.; Yu, S.H.; Xiao, Z.L.; Peeters, F.M.; Hua, J.; Imre, A.; Kwok, W.K.
	Title	Effect of sample geometry on the phase boundary of a mesoscopic superconducting loop			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	80	Issue	6	Pages	064511,1-064511,6
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We studied the effect of sample geometry on the evolution of the superconducting state in nanoscale Nb circular and square loops by transport measurements. A multistage resistive transition with temperature is found for both samples, which is related to the effect of contact leads made from the same superconducting material. The H-T phase diagrams close to Tc0 show clear periodic oscillations on top of a parabolic background, i.e., Little-Parks effect. However, the amplitude of the oscillations decreases faster in the circular loop compared to the one in the square sample. Numerical simulations are conducted within the nonlinear Ginzburg-Landau theory to show the effect of sample geometry on the nucleation of superconductivity in superconducting loop structures.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000269638800067	Publication Date	2009-08-17
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	21	Open Access
	Notes				Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:78292			Serial	833
Permanent link to this record



	Author	Zha, G.-Q.; Chen, Y.; Peeters, F.M.; Zhou, S.-P.
	Title	Impurity-induced modulations of orders in d-wave superconductors			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	80	Issue	6	Pages	064518,1-064518,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	By using a model Hamiltonian with competing antiferromagnetic (AFM) and d-wave superconductivity orders, the impurity-induced structures of orders in d-wave superconductors is investigated. We find that the transition between one-dimensional stripe and two-dimensional checkerboardlike modulation around a single nonmagnetic impurity can take place as the strength of the AFM interaction U or the impurity scattering strength V0 is varied. It is also found that the impurity-induced stripe can first transit to checkerboardlike modulation and then disappears with increasing the next-nearest-neighbor hopping strength \|t\|. Phase diagrams of V0 versus U and \|t\| for various modulations of the spin order are presented. In addition, the quantum interference effect on the modulations of orders due to two strong nonmagnetic impurities is briefly examined, and the checkerboardlike and quasistripe patterns can occur depending on the sites where two impurities are placed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000269638800074	Publication Date	2009-09-01
	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	3	Open Access
	Notes				Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:78293			Serial	1572
Permanent link to this record



	Author	Kalina, R.; Szafran, B.; Bednarek, S.; Peeters, F.M.
	Title	Magnetic-field asymmetry of electron wave packet transmission in bent channels capacitively coupled to a metal gate			Type	A1 Journal article
	Year	2009	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	102	Issue	6	Pages	066807,1-066807,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study the electron wave packet moving through a bent channel. We demonstrate that the packet transmission probability becomes an asymmetric function of the magnetic field when the electron packet is capacitively coupled to a metal plate. The coupling occurs through a nonlinear potential which translates a different kinetics of the transport for opposite magnetic-field orientations into a different potential felt by the scattered electron.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000263389500056	Publication Date	2009-02-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007;1079-7114;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	14	Open Access
	Notes				Approved	Most recent IF: 8.462; 2009 IF: 7.328
	Call Number	UA @ lucian @ c:irua:76315			Serial	1867
Permanent link to this record



	Author	Ariskin, D.A.; Schweigert, I.V.; Alexandrov, A.L.; Bogaerts, A.; Peeters, F.M.
	Title	Modeling of chemical processes in the low pressure capacitive radio frequency discharges in a mixture of Ar/C₂H₂			Type	A1 Journal article
	Year	2009	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	105	Issue	6	Pages	063305,1-063305,9
	Keywords	A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We study the properties of a capacitive 13.56 MHz discharge with a mixture of Ar/C<sub>2</sub>H<sub>2</sub> taking into account the plasmochemistry and growth of heavy hydrocarbons. A hybrid model was developed to combine the kinetic description for electron motion and the fluid approach for negative and positive ion transports and plasmochemical processes. A significant change in plasma parameters related to injection of 5.8% portion of acetylene in argon was observed and analyzed. We found that the electronegativity of the mixture is about 30%. The densities of negatively and positively charged heavy hydrocarbons are sufficiently large to be precursors for the formation of nanoparticles in the discharge volume.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000264774000059	Publication Date	2009-03-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	21	Open Access
	Notes				Approved	Most recent IF: 2.068; 2009 IF: 2.072
	Call Number	UA @ lucian @ c:irua:74496			Serial	2121
Permanent link to this record



	Author	Caignaert, V.; Abakumov, A.M.; Pelloquin, D.; Pralong, V.; Maignan, A.; Van Tendeloo, G.; Raveau, B.
	Title	A new mixed-valence ferrite with a cubic structure, YBaFe₄O₇: spin-glass-like behavior			Type	A1 Journal article
	Year	2009	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	21	Issue	6	Pages	1116-1122
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A new mixed-valence ferrite, YBaFe4O7, has been synthesized. Its unique cubic structure, with a = 8.9595(2) Å, is closely related to that of the hexagonal 114 oxides YBaCo4O7 and CaBaFe4O7. It consists of corner-sharing FeO4 tetrahedra, forming triangular and kagome layers parallel to (111)C. In fact, the YBaFe4O7 and CaBaFe4O7 structures can be described as two different ccc and chch close packings of [BaO3]∞ and [O4]∞ layers, respectively, whose tetrahedral cavities are occupied by Fe2+/Fe3+ cations. The local structure of YBaFe4O7 is characterized by a large amount of stacking faults originating from the presence of hexagonal layers in the ccc cubic close-packed YBaFe4O7 structure. In this way, they belong to the large family of spinels and hexagonal ferrites studied for their magnetic properties. Differently from all the ferrites and especially from CaBaFe4O7, which are ferrimagnetic, YBaFe4O7 is an insulating spin glass with Tg = 50 K.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000264310900019	Publication Date	2009-02-25
	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	39	Open Access
	Notes	Esteem 026019			Approved	Most recent IF: 9.466; 2009 IF: 5.368
	Call Number	UA @ lucian @ c:irua:76432			Serial	2325
Permanent link to this record



	Author	Suarez-Martinez, I.; Bittencourt, C.; Ke, X.; Felten, A.; Pireaux, J.J.; Ghijsen, J.; Drube, W.; Van Tendeloo, G.; Ewels, C.P.
	Title	Probing the interaction between gold nanoparticles and oxygen functionalized carbon nanotubes			Type	A1 Journal article
	Year	2009	Publication	Carbon	Abbreviated Journal	Carbon
	Volume	47	Issue	6	Pages	1549-1554
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The interaction between evaporated gold and pristine or oxygen plasma treated multi-walled carbon nanotubes (MWCNTs) is investigated. Experimental and theoretical results indicate that gold nucleation occurs at defect sites, whether initially present or introduced by oxygen plasma treatment. Uniform gold cluster dispersion is observed on plasma treated carbon nanotubes (CNTs) and associated with the presence of uniformly dispersed oxidized vacancy centres on the CNT surface.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Oxford	Editor
	Language		Wos	000265518700018	Publication Date	2009-02-11
	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	38	Open Access
	Notes	Pai			Approved	Most recent IF: 6.337; 2009 IF: 4.504
	Call Number	UA @ lucian @ c:irua:77267			Serial	2717
Permanent link to this record



	Author	Bittencourt, C.; van Lier, G.; Ke, X.; Suarez-Martinez, I.; Felten, A.; Ghijsen, J.; Van Tendeloo, G.; Ewels, C.O.
	Title	Spectroscopy and defect identification for fluorinated carbon nanotubes			Type	A1 Journal article
	Year	2009	Publication	ChemPhysChem : a European journal of chemical physics and physical chemistry	Abbreviated Journal	Chemphyschem
	Volume	10	Issue	6	Pages	920-925
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Multi-wall carbon nanotubes (MWCNTs) were exposed to a CF4 radio-frequency (rf) plasma. High-resolution photoelectron spectroscopy shows that the treatment effectively grafts fluorine atoms onto the MWCNTs, altering the valence electronic states. Fluorine surface concentration can be tuned by varying the exposure time. Evaporation of gold onto MWCNTs is used to mark active site formation. High-resolution transmission electron microscopy coupled with density functional theory (DFT) modelling is used to characterise the surface defects formed, indicating that the plasma treatment does not etch the tube surface. We suggest that this combination of theory and microscopy of thermally evaporated gold atoms onto the CNT surface may be a powerful approach to characterise both surface defect density as well as defect type.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000265469200011	Publication Date	2009-03-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1439-4235;1439-7641;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.075	Times cited	14	Open Access
	Notes	Iuap; Fwo			Approved	Most recent IF: 3.075; 2009 IF: 3.453
	Call Number	UA @ lucian @ c:irua:77315			Serial	3073
Permanent link to this record



	Author	Georgieva, V.; Saraiva, M.; Jehanathan, N.; Lebelev, O.I.; Depla, D.; Bogaerts, A.
	Title	Sputter-deposited Mg-Al-O thin films: linking molecular dynamics simulations to experiments			Type	A1 Journal article
	Year	2009	Publication	Journal of physics: D: applied physics	Abbreviated Journal	J Phys D Appl Phys
	Volume	42	Issue	6	Pages	065107,1-065107,8
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Using a molecular dynamics model the crystallinity of MgxAlyOz thin films with a variation in the stoichiometry of the thin film is studied at operating conditions similar to the experimental operating conditions of a dual magnetron sputter deposition system. The films are deposited on a crystalline or amorphous substrate. The Mg metal content in the film ranged from 100% (i.e. MgO film) to 0% (i.e. Al2O3 film). The radial distribution function and density of the films are calculated. The results are compared with x-ray diffraction and transmission electron microscopy analyses of experimentally deposited thin films by the dual magnetron reactive sputtering process. Both simulation and experimental results show that the structure of the MgAlO film varies from crystalline to amorphous when the Mg concentration decreases. It seems that the crystalline MgAlO films have a MgO structure with Al atoms in between.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000263824200024	Publication Date	2009-03-03
	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	37	Open Access
	Notes	Iwt			Approved	Most recent IF: 2.588; 2009 IF: 2.083
	Call Number	UA @ lucian @ c:irua:73246			Serial	3110
Permanent link to this record



	Author	Matthai, C.C.; March, N.H.; Lamoen, D.
	Title	Supercooled molecular liquids and the glassy phases of chemically bonded N, P, As, Si and Ge			Type	A1 Journal article
	Year	2009	Publication	Physics and chemistry of liquids	Abbreviated Journal	Phys Chem Liq
	Volume	47	Issue	6	Pages	607-613
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Glassy phases which have insulating character exist for a variety of monatomic species. By contrast, until recently, it has been possible to make bulk metallic glasses (BMG) by vitrification only for multicomponent systems. After a relatively brief summary on supercooling of a few molecular liquids, we review some of the recently reported results on molecular assemblies of the series N, P, As and amorphous Si and Ge. Based on these results, we suggest that the transition metals with their directional bonding might be suitable candidates for the production of BMG by vitrification.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	London	Editor
	Language		Wos	000273047400003	Publication Date	2009-11-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9104;1029-0451;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.145	Times cited	1	Open Access
	Notes	BoF			Approved	Most recent IF: 1.145; 2009 IF: 0.580
	Call Number	UA @ lucian @ c:irua:80653			Serial	3376
Permanent link to this record



	Author	Matulis, A.; Peeters, F.M.
	Title	Analogy between one-dimensional chain models and graphene			Type	A1 Journal article
	Year	2009	Publication	American journal of physics	Abbreviated Journal	Am J Phys
	Volume	77	Issue	7	Pages	595-601
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electron and hole spectrum in single and bilayer graphene is derived from known one-dimensional models, and the relation between the spectrum and symmetry of the lattice is shown.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000266976000003	Publication Date	2009-06-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0002-9505;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.069	Times cited	11	Open Access
	Notes				Approved	Most recent IF: 1.069; 2009 IF: 0.779
	Call Number	UA @ lucian @ c:irua:77381			Serial	97
Permanent link to this record



	Author	Castelano, L.K.; Hai, G.Q.; Partoens, B.; Peeters, F.M.
	Title	Artificial molecular quantum rings under magnetic field influence			Type	A1 Journal article
	Year	2009	Publication	Journal of applied physics	Abbreviated Journal	J Appl Phys
	Volume	106	Issue	7	Pages	073702,1-073702,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The ground states of a few electrons confined in two vertically coupled quantum rings in the presence of an external magnetic field are studied systematically within the current spin-density functional theory. Electron-electron interactions combined with inter-ring tunneling affect the electronic structure and the persistent current. For small values of the external magnetic field, we recover the zero magnetic field molecular quantum ring ground state configurations. Increasing the magnetic field many angular momentum, spin, and isospin transitions are predicted to occur in the ground state. We show that these transitions follow certain rules, which are governed by the parity of the number of electrons, the single-particle picture, Hunds rules, and many-body effects.
	Address
	Corporate Author				Thesis
	Publisher	American Institute of Physics	Place of Publication	New York, N.Y.	Editor
	Language		Wos	000270915600047	Publication Date	2009-10-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0021-8979;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.068	Times cited	5	Open Access
	Notes				Approved	Most recent IF: 2.068; 2009 IF: 2.072
	Call Number	UA @ lucian @ c:irua:86926			Serial	155
Permanent link to this record



	Author	Brosens, F.; Magnus, W.
	Title	Carrier transport in nanodevices: revisiting the Boltzmann and Wigner distribution functions			Type	A1 Journal article
	Year	2009	Publication	Physica status solidi: B: basic research	Abbreviated Journal	Phys Status Solidi B
	Volume	246	Issue	7	Pages	1656-1661
	Keywords	A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
	Abstract	In principle, transport of charged carriers in nanometer sized solid-state devices can be fully characterized once the non-equilibrium distribution function describing the carrier ensemble is known. In this light, we have revisited the Boltzmann and the Wigner distribution functions and the framework in which they emerge from the classical respectively quantum mechanical Liouville equation. We have assessed the method of the characteristic curves as a potential workhorse to solve the time dependent Boltzmann equation for carriers propagating through spatially non-uniform systems, such as nanodevices. In order to validate the proposed solution strategy, we numerically solve the Boltzmann equation for a one-dimensional conductor mimicking the basic features of a biased low-dimensional transistor operating in the on-state. Finally, we propose a computational scheme capable of extending the benefits of the above mentioned solution strategy when it comes to solve the Wigner-Liouville equation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Berlin	Editor
	Language		Wos	000268659100033	Publication Date	2009-04-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0370-1972;1521-3951;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.674	Times cited	8	Open Access
	Notes				Approved	Most recent IF: 1.674; 2009 IF: 1.150
	Call Number	UA @ lucian @ c:irua:77953			Serial	284
Permanent link to this record



	Author	Xu, W.; Peeters, F.M.; Lu, T.C.
	Title	Dependence of resistivity on electron density and temperature in graphene			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	79	Issue	7	Pages	073403,1-073403,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	On the basis of the momentum-balance equation derived from the Boltzmann equation in which electron interactions with impurities and acoustic and optic phonons are included, we examine the dependence of the resistivity in graphene on temperature and electron density. Simple analytical expressions for the different contributions to the resistivity are obtained. Our results reproduce recent experimental findings and we are able to understand the different temperature dependence of the resistivity for low and high density samples.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000263815800013	Publication Date	2009-02-12
	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	31	Open Access
	Notes				Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:76222			Serial	642
Permanent link to this record



	Author	Vlasov, I.I.; Barnard, A.S.; Ralchenko, V.G.; Lebedev, O.I.; Kanzyuba, M.V.; Saveliev, A.V.; Konov, V.I.; Goovaerts, E.
	Title	Nanodiamond photoemitters based on strong narrow-band luminescence from silicon-vacancy defects			Type	A1 Journal article
	Year	2009	Publication	Advanced materials	Abbreviated Journal	Adv Mater
	Volume	21	Issue	7	Pages	808-812
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Nanostructured and organic optical and electronic materials (NANOrOPT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000263737800012	Publication Date	2008-12-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0935-9648;1521-4095;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	19.791	Times cited	98	Open Access
	Notes				Approved	Most recent IF: 19.791; 2009 IF: NA
	Call Number	UA @ lucian @ c:irua:74513			Serial	2253
Permanent link to this record



	Author	Neyts, E.C.; Bogaerts, A.
	Title	Numerical study of the size-dependent melting mechanisms of nickel nanoclusters			Type	A1 Journal article
	Year	2009	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	113	Issue	7	Pages	2771-2776
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Molecular dynamics simulations were used to investigate the size-dependent melting mechanism of nickel nanoclusters of various sizes. The melting process was monitored by the caloric curve, the overall cluster Lindemann index, and the atomic Lindemann index. Size-dependent melting temperatures were determined, and the correct linear dependence on inverse diameter was recovered. We found that the melting mechanism gradually changes from dynamic coexistence melting to surface melting with increasing cluster size. These findings are of importance in better understanding carbon nanotube growth by catalytic chemical vapor deposition as the phase state of the catalyst nanoparticle codetermines the growth mechanism.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos		Publication Date	0000-00-00
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited		Open Access
	Notes				Approved	Most recent IF: 4.536; 2009 IF: 4.224
	Call Number	UA @ lucian @ c:irua:76495			Serial	2410
Permanent link to this record



	Author	Lamoen, D.; March, N.H.
	Title	Orientational disorder in some molecular solids in relation to the boson peak in glasses			Type	A1 Journal article
	Year	2009	Publication	Physics letters : A	Abbreviated Journal	Phys Lett A
	Volume	373	Issue	7	Pages	799-800
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Orientational disorder in some molecular solids is discussed in relation to the emphasis placed on transverse vibrational modes in glasses as the origin of the observed boson peak in two very recent contributions in Nature Materials. In particular, facts are here presented for (i) CH4, (ii) C60 and (iii) ethanol in their solid phases for (a) specific heat and (b) neutron scattering. The results for ethanol in particular do not fit in with the interpretation of the boson peak in terms of transverse acoustic phonons in disordered systems. Glasses will therefore have to be separated into at least two classes where the physical interpretation of the boson peak is concerned.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000263515500020	Publication Date	2009-01-09
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0375-9601;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.772	Times cited	3	Open Access
	Notes	Bof			Approved	Most recent IF: 1.772; 2009 IF: 2.009
	Call Number	UA @ lucian @ c:irua:72917			Serial	2516
Permanent link to this record



	Author	Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Matsushita, N.; Yoshimura, M.; Guitian, F.
	Title	Rational synthesis of a nanocrystalline calcium phosphate cement exhibiting rapid conversion to hydroxyapatite			Type	A1 Journal article
	Year	2009	Publication	Materials science and engineering: part C: biomimetic materials	Abbreviated Journal	Mat Sci Eng C-Mater
	Volume	29	Issue	7	Pages	2124-2132
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The rational synthesis, comprehensive characterization, and mechanical and micromechanical properties of a calcium phosphate cement are presented. Hydroxyapatite cement biomaterial was synthesized from reactive sub-micrometer-sized dicalcium phosphate dihydrate and tetracalcium phosphate via a dissolution-precipitation reaction using water as the liquid phase. As a result nanostructured, Ca-deficient and carbonated B-type hydroxyapatite is formed. The cement shows good processibility, sets in 22 ± 2 min and entirely transforms to the end product after 6 h of setting reaction, one of the highest conversion rates among previously reported for calcium phosphate cements based on dicalcium and tetracalcium phosphates. The combination of all elucidated physical-chemical traits leads to an essential bioactivity and biocompatibility of the cement, as revealed by in vitro acellular simulated body fluid and cell culture studies. The compressive strength of the produced cement biomaterial was established to be 25 ± 3 MPa. Furthermore, nanoindentation tests were performed directly on the cement to probe its local elasticity and plasticity at sub-micrometer/micrometer level. The measured elastic modulus and hardness were established to be Es = 23 ± 3.5 and H = 0.7 ± 0.2 GPa, respectively. These values are in close agreement with those reported in literature for trabecular and cortical bones, reflecting good elastic and plastic coherence between synthesized cement biomaterial and human bones.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lausanne	Editor
	Language		Wos	000270159200008	Publication Date	2009-04-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0928-4931;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.164	Times cited	18	Open Access
	Notes	Esteem 026019			Approved	Most recent IF: 4.164; 2009 IF: NA
	Call Number	UA @ lucian @ c:irua:79312			Serial	2812
Permanent link to this record



	Author	Schattschneider, P.; Verbeeck, J.; Hamon, A.L.
	Title	Real space maps of atomic transitions			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	7	Pages	781-787
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Considering the rapid technical development of transmission electron microscopes, we investigate the possibility to map electronic transitions in real space on the atomic scale. To this purpose, we analyse the information carried by the scatterer's initial and final state wave functions and the role of the different atomic transition channels for the inelastic scattering cross section. It is shown that the change in the magnetic quantum number in the transition can be mapped. Two experimental set-ups are proposed, one blocking half the diffraction plane, the other one using a cylinder lens for imaging. Both methods break the conventional circular symmetry in the electron microscope making it possible to detect the handedness of electronic transitions as an asymmetry in the image intensity. This finding is of important for atomic resolution energy-loss magnetic chiral dichroism (EMCD), allowing to obtain the magnetic moments of single atoms.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000266787900002	Publication Date	2009-03-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-3991;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.843	Times cited	10	Open Access
	Notes	J.V. acknowledges the FWO-Vlaanderen for support (contract no. G.0147.06) and the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM.			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:77360UA @ admin @ c:irua:77360			Serial	2829
Permanent link to this record



	Author	Müller, K.; Schowalter, M.; Jansen, J.; Tsuda, K.; Titantah, J.; Lamoen, D.; Rosenauer, A.
	Title	Refinement of the 200 structure factor for GaAs using parallel and convergent beam electron nanodiffraction data			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	7	Pages	802-814
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We present a new method to measure structure factors from electron spot diffraction patterns recorded under almost parallel illumination in transmission electron microscopes. Bloch wave refinement routines have been developed to refine the crystal thickness, its orientation and structure factors by comparison of experimentally recorded and calculated intensities. Our method requires a modicum of computational effort, making it suitable for contemporary personal computers. Frozen lattice and Bloch wave simulations of GaAs diffraction patterns are used to derive optimised experimental conditions. Systematic errors are estimated from the application of the method to simulated diffraction patterns and rules for the recognition of physically reasonable initial refinement conditions are derived. The method is applied to the measurement of the 200 structure factor for GaAs. We found that the influence of inelastically scattered electrons is negligible. Additionally, we measured the 200 structure factor from zero loss filtered two-dimensional convergent beam electron diffraction patterns. The precision of both methods is found to be comparable and the results agree well with each other. A deviation of more than 20% from isolated atom scattering data is observed, whereas close agreement is found with structure factors obtained from density functional theory [A. Rosenauer, M. Schowalter, F. Glas, D. Lamoen, Phys. Rev. B 72 (2005), 085326-1], which account for the redistribution of electrons due to chemical bonding via modified atomic scattering amplitudes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000266787900005	Publication Date	2009-03-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-3991;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.843	Times cited	8	Open Access
	Notes	Fwo; G.0425.05; Esteem; Ant 200611271505			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:77361			Serial	2856
Permanent link to this record



	Author	van der Snickt, G.; Dik, J.; Cotte, M.; Janssens, K.; Jaroszewicz, J.; de Nolf, W.; Groenewegen, J.; van der Loeff, L.
	Title	Characterization of a degraded cadmium yellow (CdS) pigment in an oil painting by means of synchrotron radiation based X-ray techniques			Type	A1 Journal article
	Year	2009	Publication	Analytical chemistry	Abbreviated Journal	Anal Chem
	Volume	81	Issue	7	Pages	2600-2610
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	On several paintings of James Ensor (1860−1949), a gradual fading of originally bright yellow areas, painted with the pigment cadmium yellow (CdS), is observed. Additionally, in some areas exposed to light, the formation of small white-colored globules on top of the original paint surface is observed. In this paper the chemical transformation leading to the color change and to the formation of the globules is elucidated. Microscopic X-ray absorption near-edge spectroscopy (ì-XANES) experiments show that sulfur, originally present in sulfidic form (S2−), is oxidized during the transformation to the sulfate form (S6+). Upon formation (at or immediately below the surface), the highly soluble cadmium sulfate is assumed to be transported to the surface in solution and reprecipitates there, forming the whitish globules. The presence of cadmium sulfate (CdSO4·2H2O) and ammonium cadmium sulfate [(NH4)2Cd(SO4)2] at the surface is confirmed by microscopic X-ray diffraction measurements, where the latter salt is suspected to result from a secondary reaction of cadmium sulfate with ammonia. Measurements performed on cross sections reveal that the oxidation front has penetrated into the yellow paint down to ca. 1−2 ìm. The morphology and elemental distribution of the paint and degradation product were examined by means of scanning electron microscopy equipped with an energy-dispersive spectrometer (SEM-EDS) and synchrotron radiation based micro-X-ray fluorescence spectrometry (SR ì-XRF). In addition, ultraviolet-induced visible fluorescence photography (UIVFP) revealed itself to be a straightforward technique for documenting the occurrence of this specific kind of degradation on a macroscale by painting conservators.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000264759400025	Publication Date	2009-03-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0003-2700; 5206-882x	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.32	Times cited	91	Open Access
	Notes				Approved	Most recent IF: 6.32; 2009 IF: 5.214
	Call Number	UA @ admin @ c:irua:76415			Serial	5501
Permanent link to this record



	Author	Bugani, S.; Modugno, F.; Lucejko, J.J.; Giachi, G.; Cagno, S.; Cloetens, P.; Janssens, K.; Morselli, L.
	Title	Study on the impregnation of archaeological waterlogged wood with consolidation treatments using synchrotron radiation microtomography			Type	A1 Journal article
	Year	2009	Publication	Analytical and bioanalytical chemistry	Abbreviated Journal	Anal Bioanal Chem
	Volume	395	Issue	7	Pages	1977-1985
	Keywords	A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
	Abstract	In favourable conditions of low temperature and low oxygen concentration, archaeological waterlogged wooden artefacts, such as shipwrecks, can survive with a good state of preservation. Nevertheless, anaerobic bacteria can considerably degrade waterlogged wooden objects with a significant loss in polysaccharidic components. Due to these decay processes, wood porosity and water content increase under ageing. In such conditions, the conservation treatments of archaeological wooden artefacts often involve the replacement of water with substances which fill the cavities and help to prevent collapse and stress during drying. The treatments are very often expensive and technically difficult, and their effectiveness very much depends on the chemical and physical characteristics of the substances used for impregnation. Also important are the degree of cavity-filling, penetration depth and distribution in the structure of the wood. In this study, the distribution in wood cavities of some mixtures based on polyethylene glycols and colophony, used for the conservation of waterlogged archaeological wood, was investigated using synchrotron radiation X-ray computed microtomography (SR-A mu CT). This non-destructive imaging technique was useful for the study of the degraded waterlogged wood and enabled us to visualise the morphology of the wood and the distribution of the materials used in the wood treatments. The study has shown how deposition is strictly related to the dimension of the wooden cavities. The work is currently proceeding with the comparison of synchrotron observations with the data of the solutions viscosity and with those of the properties imparted to the wood by the treatments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000272017000005	Publication Date	2009-09-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1618-2642	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.431	Times cited	30	Open Access
	Notes				Approved	Most recent IF: 3.431; 2009 IF: 3.480
	Call Number	UA @ admin @ c:irua:94493			Serial	5853
Permanent link to this record