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“Tailored vapor-phase growth of CuxO-TiO2(x=1,2) nanomaterials decorated with Au particles”. Barreca D, Carraro G, Gasparotto A, Maccato C, Lebedev OI, Parfenova A, Turner S, Tondello E, Van Tendeloo G, Langmuir: the ACS journal of surfaces and colloids 27, 6409 (2011). http://doi.org/10.1021/la200698t
Abstract: We report on the fabrication of CuxOTiO2 (x = 1, 2) nanomaterials by an unprecedented vapor-phase approach. The adopted strategy involves the growth of porous CuxO matrices by means of chemical vapor deposition (CVD), followed by the controlled dispersion of TiO2 nanoparticles. The syntheses are performed on Si(100) substrates at temperatures of 400550 °C under wet oxygen atmospheres, adopting Cu(hfa)2·TMEDA (hfa =1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine) and Ti(O-iPr)2(dpm)2 (O-iPr = isopropoxy; dpm = 2,2,6,6-tetramethyl-3,5-heptanedionate) as copper and titanium precursors, respectively. Subsequently, finely dispersed gold nanoparticles are introduced in the as-prepared systems via radio frequency (RF)-sputtering under mild conditions. The synthesis process results in the formation of systems with chemical composition and nano-organization strongly dependent on the nature of the initial CuxO matrix and on the deposited TiO2 amount. The decoration with low-size gold clusters paves the way to the engineering of hierarchically organized nanomaterials.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.833
Times cited: 36
DOI: 10.1021/la200698t
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“Vapor Phase Fabrication of Nanoheterostructures Based on ZnO for Photoelectrochemical Water Splitting”. Barreca D, Carraro G, Gasparotto A, Maccato C, Altantzis T, Sada C, Kaunisto K, Ruoko T-P, Bals S, Advanced Materials Interfaces 4, 1700161 (2017). http://doi.org/10.1002/admi.201700161
Abstract: Nanoheterostructures based on metal oxide semiconductors have emerged
as promising materials for the conversion of sunlight into chemical energy.
In the present study, ZnO-based nanocomposites have been developed by
a hybrid vapor phase route, consisting in the chemical vapor deposition
of ZnO systems on fluorine-doped tin oxide substrates, followed by the
functionalization with Fe2O3 or WO3 via radio frequency-sputtering. The
target systems are subjected to thermal treatment in air both prior and after
sputtering, and their properties, including structure, chemical composition,
morphology, and optical absorption, are investigated by a variety of characterization
methods. The obtained results evidence the formation of highly
porous ZnO nanocrystal arrays, conformally covered by an ultrathin Fe2O3
or WO3 overlayer. Photocurrent density measurements for solar-triggered
water splitting reveal in both cases a performance improvement with respect
to bare zinc oxide, that is mainly traced back to an enhanced separation of
photogenerated charge carriers thanks to the intimate contact between the
two oxides. This achievement can be regarded as a valuable result in view of
future optimization of similar nanoheterostructured photoanodes.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.279
Times cited: 30
DOI: 10.1002/admi.201700161
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“Optically detected magnetophonon resonance in GaAs-GaAlAs heterojunctions”. Barnes DJ, Nicholas RJ, Watts M, Peeters FM, Wu XG, Devreese JT, Langerak CJ, Singleton J, Harris JJ, Foxon CT, (1991)
Keywords: P3 Proceeding; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
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“The observation and theory of optically detected magnetophonon resonance”. Barnes DJ, Nicholas RJ, Peeters FM, Wu XG, Devreese JT, Singleton J, Langerak CJGM, Harris JJ, Foxon CT, Physical review letters 66, 794 (1991)
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 7.512
Times cited: 38
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“Barium-based manganites Ln1-xBaxMnO3 with Ln = {Pr, La}: phase transitions and magnetoresistance properties”. Barnabé, A, Millange F, Maignan A, Hervieu M, Raveau B, Van Tendeloo G, Laffez P, Chem. mater. 10, 252 (1998). http://doi.org/10.1021/cm9704084
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 48
DOI: 10.1021/cm9704084
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“Electrochemical identification of hazardous phenols and their complex mixtures in real samples using unmodified screen-printed electrodes”. Barich H, Cánovas R, De Wael K, Journal of electroanalytical chemistry : an international journal devoted to all aspects of electrode kynetics, interfacial structure, properties of electrolytes, colloid and biological electrochemistry. 904, 115878 (2022). http://doi.org/10.1016/J.JELECHEM.2021.115878
Abstract: The electrochemical behavior of some of the most relevant endocrine-disrupting phenols using unmodified carbon screen-printed electrodes (SPEs) is described for the first time. Experiments were made to assess the electrochemical behavior of phenol (PHOH), pentachlorophenol (PCP), 4-tert octylphenol (OP) and bisphenol A (BPA) and their determination in the most favorable conditions, using voltammetric methods such as cyclic voltammetry (CV), linear sweep voltammetry (LSV) and square wave voltammetry (SWV) in Britton Robinson (BR) buffer. Further, the usefulness of the electrochemical approach was validated with real samples from a local river and was compared to commercial phenols test kit, which is commonly used for on-site screening in industrial streams and wastewaters. Finally, the approach was compared with a lab-bench standard method using real samples, i.e., high-performance liquid chromatography with a photodiode array detector (HPLC-DAD).
Keywords: A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Impact Factor: 4.5
DOI: 10.1016/J.JELECHEM.2021.115878
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“Sol-gel hot injection synthesis of ZnO nanoparticles into a porous silica matrix and reaction mechanism”. Barhoum A, Van Assche G, Rahier H, Fleisch M, Bals S, Delplancked M-P, Leroux F, Bahnemann D, Materials &, design 119, 270 (2017). http://doi.org/10.1016/J.MATDES.2017.01.059
Abstract: Despite the enormous interest in the properties and applications of porous silica matrix, only a few attempts have been reported to deposit metal and metal oxide nanoparticles (NPs) inside the porous silica matrix. We report a simple approach (i.e. sol-gel hot injection) for insitu synthesis of ZnO NPs inside a porous silica matrix. Control of the Zn:Si molar ratio, reaction temperature, pH value, and annealing temperature permits formation of ZnO NPs (<= 10 nm) inside a porous silica particles, without additives or organic solvents. Results revealed that a solid state reaction inside the ZnO/SiO2 nanocomposites occurs with increasing the annealing temperature. The reaction of ZnO NPs with SiO2 matrix was insignificant up to approximately 500 degrees C. However, ZnO NPs react strongly with the silica matrix when the nanocomposites are annealed at temperatures above 700 degrees C. Extensive annealing of the ZnO/SiO2 nanocomposite at 900 degrees C yields 3D structures made of 500 nm rod-like, 5-7 pm tube-like and 35 pm needle-like Zn2SiO4 crystals. A possible mechanism for forming ZnO NPs inside porous silica matrix and phase transformation of the ZnO/SiO2 nanocomposites into 3D architectures of Zn2SiO4 are carefully discussed. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.364
Times cited: 43
DOI: 10.1016/J.MATDES.2017.01.059
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“Band structure, density of states, and transmission in graphene bilayer superlattices”. Barbier M, Vasilopoulos P, Peeters FM, Pereira JM, AIP conference proceedings 1199, 547 (2009). http://doi.org/10.1063/1.3295550
Abstract: The energy spectrum and density of states of graphene bilayer superlattices (SLs) are evaluated. We take into account doping and/or gating of the layers as well as tunnel coupling between them. In addition, we evaluate the transmission through such SLs and through single or double barriers. The transmission exhibits a strong dependence on the direction of the incident wave vector.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
DOI: 10.1063/1.3295550
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“Bilayer graphene with single and multiple electrostatic barriers: band structure and transmission”. Barbier M, Vasilopoulos P, Peeters FM, Pereira JM, Physical review : B : solid state 79, 155402 (2009). http://doi.org/10.1103/PhysRevB.79.155402
Abstract: We evaluate the electronic transmission and conductance in bilayer graphene through a finite number of potential barriers. Further, we evaluate the dispersion relation in a bilayer graphene superlattice with a periodic potential applied to both layers. As a model we use the tight-binding Hamiltonian in the continuum approximation. For zero bias the dispersion relation shows a finite gap for carriers with zero momentum in the direction parallel to the barriers. This is in contrast to single-layer graphene where no such gap was found. A gap also appears for a finite bias. Numerical results for the energy spectrum, conductance, and the density of states are presented and contrasted with those pertaining to single-layer graphene.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 74
DOI: 10.1103/PhysRevB.79.155402
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“Dirac electrons in a Kronig-Penney potential: dispersion relation and transmission periodic in the strength of the barriers”. Barbier M, Vasilopoulos P, Peeters FM, Physical review : B : solid state 80, 205415 (2009). http://doi.org/10.1103/PhysRevB.80.205415
Abstract: The transmission T and conductance G through one or multiple one-dimensional, ä-function barriers of two-dimensional fermions with a linear energy spectrum are studied. T and G are periodic functions of the strength P of the ä-function barrier V(x,y)/ℏvF=Pä(x). The dispersion relation of a Kronig-Penney (KP) model of a superlattice is also a periodic function of P and causes collimation of an incident electron beam for P=2ðn and n integer. For a KP superlattice with alternating sign of the height of the barriers the Dirac point becomes a Dirac line for P=(n+1/2)ð.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 93
DOI: 10.1103/PhysRevB.80.205415
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“Extra Dirac points in the energy spectrum for superlattices on single-layer graphene”. Barbier M, Vasilopoulos P, Peeters FM, Physical review : B : condensed matter and materials physics 81, 075438 (2010). http://doi.org/10.1103/PhysRevB.81.075438
Abstract: We investigate the emergence of extra Dirac points in the electronic structure of a periodically spaced barrier system, i.e., a superlattice, on single-layer graphene, using a Dirac-type Hamiltonian. Using square barriers allows us to find analytic expressions for the occurrence and location of these new Dirac points in k space and for the renormalization of the electron velocity near them in the low-energy range. In the general case of unequal barrier and well widths the new Dirac points move away from the Fermi level and for given heights of the potential barriers there is a minimum and maximum barrier width outside of which the new Dirac points disappear. The effect of these extra Dirac points on the density of states and on the conductivity is investigated.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 211
DOI: 10.1103/PhysRevB.81.075438
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“Kronig-Penney model on bilayer graphene : spectrum and transmission periodic in the strength of the barriers”. Barbier M, Vasilopoulos P, Peeters FM, Physical review : B : condensed matter and materials physics 82, 235408 (2010). http://doi.org/10.1103/PhysRevB.82.235408
Abstract: We show that the transmission through single and double δ-function potential barriers of strength P=VWb/ℏvF in bilayer graphene is periodic in P with period π. For a certain range of P values we find states that are bound to the potential barrier and that run along the potential barrier. Similar periodic behavior is found for the conductance. The spectrum of a periodic succession of δ-function barriers (Kronig-Penney model) in bilayer graphene is periodic in P with period 2π. For P smaller than a critical value Pc, the spectrum exhibits two Dirac points while for P larger than Pc an energy gap opens. These results are extended to the case of a superlattice of δ-function barriers with P alternating in sign between successive barriers; the corresponding spectrum is periodic in P with period π.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 34
DOI: 10.1103/PhysRevB.82.235408
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“Single-layer and bilayer graphene superlattices: collimation, additional Dirac points and Dirac lines”. Barbier M, Vasilopoulos P, Peeters FM, Philosophical transactions of the Royal Society : mathematical, physical and engineering sciences 368, 5499 (2010). http://doi.org/10.1098/rsta.2010.0218
Abstract: We review the energy spectrum and transport properties of several types of one-dimensional superlattices (SLs) on single-layer and bilayer graphene. In single-layer graphene, for certain SL parameters an electron beam incident on an SL is highly collimated. On the other hand, there are extra Dirac points generated for other SL parameters. Using rectangular barriers allows us to find analytical expressions for the location of new Dirac points in the spectrum and for the renormalization of the electron velocities. The influence of these extra Dirac points on the conductivity is investigated. In the limit of δ-function barriers, the transmission T through and conductance G of a finite number of barriers as well as the energy spectra of SLs are periodic functions of the dimensionless strength P of the barriers, Graphic, with vF the Fermi velocity. For a KronigPenney SL with alternating sign of the height of the barriers, the Dirac point becomes a Dirac line for P = π/2+nπ with n an integer. In bilayer graphene, with an appropriate bias applied to the barriers and wells, we show that several new types of SLs are produced and two of them are similar to type I and type II semiconductor SLs. Similar to single-layer graphene SLs, extra Dirac points are found in bilayer graphene SLs. Non-ballistic transport is also considered.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.97
Times cited: 64
DOI: 10.1098/rsta.2010.0218
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“Dirac and Klein-Gordon particles in one-dimensional periodic potentials”. Barbier M, Peeters FM, Vasilopoulos P, Milton Pereira J, Physical review : B : condensed matter and materials physics 77, 115446 (2008). http://doi.org/10.1103/PhysRevB.77.115446
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 191
DOI: 10.1103/PhysRevB.77.115446
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“Snake states and Klein tunneling in a graphene Hall bar with a pn-junction”. Barbier M, Papp G, Peeters FM, Applied physics letters 100, 163121 (2012). http://doi.org/10.1063/1.4704667
Abstract: The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667]
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 20
DOI: 10.1063/1.4704667
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Barbier M (2012) Transport properties of nanostructures and superlattices on single-layer and bilayer graphene. Antwerpen
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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“Study of rechargeable batteries using advanced spectroscopic and computational techniques”. Barbiellini B, Kuriplach J, Saniz R, Condensed Matter 6, 26 (2021). http://doi.org/10.3390/CONDMAT6030026
Abstract: Improving the efficiency and longevity of energy storage systems based on Li- and Na-ion rechargeable batteries presents a major challenge. The main problems are essentially capacity loss and limited cyclability. These effects are due to a hierarchy of factors spanning various length and time scales, interconnected in a complex manner. As a consequence, and in spite of several decades of research, a proper understanding of the ageing process has remained somewhat elusive. In recent years, however, combinations of advanced spectroscopy techniques and first-principles simulations have been applied with success to tackle this problem. In this Special Issue, we are pleased to present a selection of articles that, by precisely applying these methods, unravel key aspects of the reduction-oxidation reaction and intercalation processes. Furthermore, the approaches presented provide improvements to standard diagnostic and characterisation techniques, enabling the detection of possible Li-ion flow bottlenecks causing the degradation of capacity and cyclability.
Keywords: Editorial; Electron microscopy for materials research (EMAT)
DOI: 10.3390/CONDMAT6030026
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“Non-conventional vortex configurations in a mesoscopic flat disk”. Barba-Ortega J, Sardella E, Aguiar JA, Peeters FM, Physica: C : superconductivity 487, 47 (2013). http://doi.org/10.1016/j.physc.2013.01.021
Abstract: The influence of superficial defects on the vortex configurations of a thin superconducting disk is investigated within the time dependent Ginzburg-Landau formalism. The free energy, magnetization, vorticity, and the Cooper pair density are calculated for both metastable and stable vortex configurations and different number of defects on its surface in the presence of an external magnetic field applied perpendicular to the disk area. We show that the competition between the confinement geometry and the geometric position of the defects leads to non-conventional vortex configurations which are not compatible with the symmetry of the sample geometry. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.404
Times cited: 17
DOI: 10.1016/j.physc.2013.01.021
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“Rheology of amorphous olivine thin films characterized by nanoindentation”. Baral P, Orekhov A, Dohmen R, Coulombier M, Raskin JP, Cordier P, Idrissi H, Pardoen T, Acta Materialia 219, 117257 (2021). http://doi.org/10.1016/J.ACTAMAT.2021.117257
Abstract: The rheological properties of amorphous olivine thin films deposited by pulsed laser deposition have been studied based on ambient temperature nanoindentation under constant strain-rate as well as re-laxation conditions. The amorphous olivine films exhibit a viscoelastic-viscoplastic behavior with a significant rate dependency. The strain-rate sensitivity m is equal to similar to 0 . 05 which is very high for silicates, indicating a complex out-of-equilibrium structure. The minimum apparent activation volume determined from nanoindentation experiments corresponds to Mg and Fe atomic metallic sites in the (Mg,Fe)(2)SiO4 crystalline lattice. The ambient temperature creep behavior of the amorphous olivine films differs very much from the one of single crystal olivine. This behavior directly connects to the recent demonstration of the activation of grain boundary sliding in polycrystalline olivine following grain boundary amorphization under high-stress. (C) 2021 The Authors. Published by Elsevier Ltd on behalf of Acta Materialia Inc.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 5.301
DOI: 10.1016/J.ACTAMAT.2021.117257
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“Pressure-Collapsed Amorphous Mg(BH4)(2): An Ultradense Complex Hydride Showing a Reversible Transition to the Porous Framework”. Ban V, Soloninin AV, Skripov AV, Hadermann J, Abakumov A, Filinchuk Y, The journal of physical chemistry: C : nanomaterials and interfaces 118, 23402 (2014). http://doi.org/10.1021/jp507286m
Abstract: Hydrogen-storage properties of complex hydrides depend of their form, such as a polymorphic form or an eutectic mixture. This Paper reports on an easy and reproducible way to synthesize a new stable form of magnesium borohydride by pressure-induced collapse of the porous gamma-Mg(BH4)(2). This amorphous complex hydride was investigated by temperature-programmed synchrotron X-ray diffraction (SXRD), transmission electron microscopy (TEM), thermogravimetric analysis, differential scanning calorimetry analysis, and Raman spectroscopy, and the dynamics of the BH4 reorientation was studied by spinlattice relaxation NMR spectroscopy. No long-range order is observed in the lattice region by Raman spectroscopy, while the internal vibration modes of the BH4 groups are the same as in the crystalline state. A hump at 4.9 angstrom in the SXRD pattern suggests the presence of nearly linear MgBH4 Mg fragments constituting all the known crystalline polymorphs of Mg(BH4)(2), which are essentially frameworks built of tetrahedral Mg nodes and linear BH4 linkers. TEM shows that the pressure-collapsed phase is amorphous down to the nanoscale, but surprisingly, SXRD reveals a transition at similar to 90 degrees C from the dense amorphous state (density of 0.98 g/cm(3)) back to the porous ? phase having only 0.55 g/cm(3) crystal density. The crystallization is slightly exothermic, with the enthalpy of -4.3 kJ/mol. The volumetric hydrogen density of the amorphous form is 145 g/L, one of the highest among hydrides. Remarkably, this form of Mg(BH4)2 has different reactivity compared to the crystalline forms. The parameters of the reorientational motion of BH4 groups in the amorphous Mg(BH4)(2) found from NMR measurements differ significantly from those in the known crystalline forms. The behavior of the nuclear spinlattice relaxation rates can be described in terms of a Gaussian distribution of the activation energies centered on 234 +/- 9 meV with the dispersion of 100 +/- 10 meV.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 4.536
Times cited: 23
DOI: 10.1021/jp507286m
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“Importance of design and operating parameters in a sonication system for viscous solutions : effects of input power, horn tip diameter and reactor capacity”. Bampouli A, Goris Q, Hussain MN, Louisnard O, Stefanidis GD, Van Gerven T, Chemical engineering and processing 198, 109715 (2024). http://doi.org/10.1016/J.CEP.2024.109715
Abstract: This study investigates the distribution of ultrasound (US) energy in a batch system for solutions with viscosity ranging from 1 to approximately 3000 mPas. Sonication was performed using horn type configurations operating at 20-30 kHz and rated power capacity of 50 or 200 W. Two different tip diameters (3 or 7 mm) and two insertion depths (35 or 25 mm) within vessels of different sizes ( approximate to 60 or 130 ml) were utilized. Additionally, a special conical tip design was employed. For each experimental setup, the calorimetric efficiency was estimated, the cavitationally active regions were visualized using the sonochemiluminescence (SCL) method and bubble cluster formation inside the vessel was macroscopically observed using a high speed camera (HSC). In the viscosity range tested, the calorimetry results showed that the efficiency and continuous operation of the device depend on both the rated power and the horn tip diameter. The ratio between electrical and calorimetric power input remained consistently around 40 to 50% across the different configurations for water, but for the 123.2 mPas solution exhibited significant variation ranging from 40 to 85%. Moreover, the power density in the smaller reactor was found to be nearly double compared to the larger one. The SCL analysis showed multiple cavitationally active zones in all setups, and the zones intensity decreased considerably with increase of the solutions viscosity. The results for the cone tip were not conclusive, but can be used as the basis for further investigation. The current research highlights the importance of thoroughly understanding the impact of each design parameter, and of establishing characterization methodologies to assist in the future development of scaled-up, commercial applications.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 4.3
DOI: 10.1016/J.CEP.2024.109715
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“On the relationship between morphology, composition and structure of Al-Cu-Fe crystals and quasicrystals”. Balzuweit K, Meekes H, Van Tendeloo G, de Boer JL, Philosophical magazine: B: physics of condensed matter: electronic, optical and magnetic properties 67, 513 (1993). http://doi.org/10.1080/13642819308207689
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 10
DOI: 10.1080/13642819308207689
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“Modeling the charge deposition in quartz grains during natural irradiation and its influence on the optically stimulated luminescence signal”. Baly L, Quesada I, Murray AS, Martin G, van Espen P, Arteche R, Jain M, Radiation Measurements 142, 106564 (2021). http://doi.org/10.1016/J.RADMEAS.2021.106564
Abstract: The rate of charge deposition in quartz grains irradiated in natural conditions is computed by radiation transport modeling. Quartz luminescence models are modified with the addition of the resulting charge deposition term, and the influence of this process on the optically stimulated luminescence (OSL) signal is analyzed. The results indicate that the charge deposition occurring in the quartz grain during the time of residence within rock could lead to the depletion of trapped holes in the recombination centres. For the two different quartz models investigated here, complete depletion is expected to occur for rock ages between 500 Ma and 1100 Ma. It is predicted that for sedimentary quartz derived from such rocks, the OSL signal is dominated by the slow component. It was also found that the shape and saturation level of the natural sensitivity-corrected dose response curve (DRC) of quartz is affected by the charge deposition; specifically, a linear reduction of the saturation level with the age of the rock is observed.
Keywords: A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 1.442
DOI: 10.1016/J.RADMEAS.2021.106564
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“Variation of K X-ray fluorescence cross-sections of Cu, Y and Ba in YBa2Cu3O7-\delta superconductor”. Baltas H, Čevik U, Solid state communications 149, 231 (2009). http://doi.org/10.1016/J.SSC.2008.11.010
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.
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
DOI: 10.1016/J.SSC.2008.11.010
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“Quantitative electron microscopy of (Bi,Pb)2Sr2Ca2Cu3O10+\delta/Ag multifilament tapes during initial stages of annealing”. Bals S, Verbeeck J, Van Tendeloo G, Liu Y-L, Grivel J-C, Journal of the American Ceramic Society 88, 431 (2005). http://doi.org/10.1111/j.1551-2916.2005.00094.x
Abstract: The microstructural and compositional evolution during initial annealing of a superconducting (Bi,Pb)(2)Sr2Ca2Cu3O10+delta/Ag tape is studied using quantitative transmission electron microscopy. Special attention is devoted to the occurrence of Pb-rich liquids, which are crucial for the Bi2Sr2CaCu2O8+delta to (Bi,Pb)(2)Sr2Ca2Cu3O10+delta transformation. Ca and/or Pb-rich (Bi,Pb)(2)Sr2CaCu2O8+delta grains dissolve into a liquid, which reacts with Ca-rich phases to increase the liquid's Ca-content. This leads to (Bi,Pb)(2)Sr2Ca2Cu3O10+delta formation. Apparently, a Ca/Sr ratio of around I is sufficient to keep (Bi,Pb)(2)Sr2Ca2Cu3O10+delta nucleation going. It is confirmed that Ag particles are transported from the Ag-sheath into the oxide core by the liquid and not by mechanical treatment of the tape.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.841
Times cited: 1
DOI: 10.1111/j.1551-2916.2005.00094.x
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“Why are sputter deposited Nd1+xBa2-xCu3O7-\delta thin films flatter than NdBa2Cu3O7-\delta films?”.Bals S, Van Tendeloo G, Salluzzo M, Maggio-Aprile I, Applied physics letters 79, 3660 (2001). http://doi.org/10.1063/1.1421622
Abstract: High-resolution electron microscopy and scanning tunneling microscopy have been used to compare the microstructure of NdBa2Cu3O7-delta and Nd1+xBa2-xCu3O7-delta thin films. Both films contain comparable amounts of Nd2CuO4 inclusions. Antiphase boundaries are induced by unit cell high steps at the substrate or by a different interface stacking. In Nd1+xBa2-xCu3O7-delta the antiphase boundaries tend to annihilate by the insertion of extra Nd layers. Stacking faults, which can be characterized as local Nd2Ba2Cu4O9 inclusions, also absorb the excess Nd. A correlation is made between the excess Nd and the absence of growth spirals at the surface of the Nd-rich films. (C) 2001 American Institute of Physics.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 13
DOI: 10.1063/1.1421622
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“Transmission electron microscopy on interface engineered superconducting thin films”. Bals S, Van Tendeloo G, Rijnders G, Huijben M, Leca V, Blank DHA, IEEE transactions on applied superconductivity 13, 2834 (2003). http://doi.org/10.1109/TASC.2003.812023
Abstract: Transmission electron microscopy is used to evaluate different deposition techniques, which optimize the microstructure and physical properties of superconducting thin films. High-resolution electron microscopy proves that the use of an YBa2Cu2Ox buffer layer can avoid a variable interface configuration in YBa2Cu3O7-delta thin films grown on SrTiO3. The growth can also be controlled at an atomic level by, using sub-unit cell layer epitaxy, which results in films with high quality and few structural defects. Epitaxial strain in Sr0.85La0.15CuO2 infinite layer thin films influences the critical temperature of these films, as well as the microstructure. Compressive stress is released by a modulated or a twinned microstructure, which eliminates superconductivity. On the other hand, also tensile strain seems to lower the critical temperature of the infinite layer.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 13
DOI: 10.1109/TASC.2003.812023
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“Optimisation of superconducting thin films by TEM”. Bals S, Van Tendeloo G, Rijnders G, Blank DHA, Leca V, Salluzzo M, Physica: C : superconductivity 372/376, 711 (2002). http://doi.org/10.1016/S0921-4534(02)00838-9
Abstract: High-resolution electron microscopy is used to study the initial growth of different REBa2CU3O7-5 thin films. In DyBa2CU3O7-5 ultra-thin films, deposited on TiO2 terminated SrTiO3, two different types of interface arrangements occur: bulk-SrO-TiO2-BaO-CuO-BaO-CuO2-Dy-CuO2-BaO-bulk and bulk-SrO-TiO2-BaO-CuO2-Dy-CuO2-BaO-CuO-BaO-bulk. This variable growth sequence is the origin of the presence of antiphase boundaries. In Nd1+xBa2-xCu3O7-5 thin films, antiphase boundaries tend to annihilate by the insertion of extra Nd-layers. This annihilation is correlated with the flat morphology of the film and the absence of growth spirals at the surface of the Nd-rich films. (C) 2002 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.404
Times cited: 6
DOI: 10.1016/S0921-4534(02)00838-9
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“A new approach for electron tomography: annular dark-field transmission electron microscopy”. Bals S, Van Tendeloo G, Kisielowski C, Advanced materials 18, 892 (2006). http://doi.org/10.1002/adma.200502201
Abstract: Annular dark-field transmission electron microscopy uses an annular objective aperture that blocks the central beam and all electrons scattered up to a certain serniangle. A contrast suitable for electron tomography is generated and 3D reconstructions of CdTe tetrapods and C nanotubes (see figure) are successfully obtained. With short exposure times and high contrast, the technique could be useful not only for materials science, but also for biological applications.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 19.791
Times cited: 53
DOI: 10.1002/adma.200502201
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“Structural, chemical and electronic characterization of ceramic materials using quantitative (scanning) transmission electron microscopy”. Bals S, Van Aert S, Verbeeck J, Van Tendeloo G, Microscopy and microanalysis 13, 332 (2007). http://doi.org/10.1017/S1431927607081664
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.891
DOI: 10.1017/S1431927607081664
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