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Author | Grubova, I.Y.; Surmeneva, M.A.; Huygh, S.; Surmenev, R.A.; Neyts, E.C. | ||||
Title | Effects of silicon doping on strengthening adhesion at the interface of the hydroxyapatite-titanium biocomposite : a first-principles study | Type | A1 Journal article | ||
Year | 2019 | Publication | Computational materials science | Abbreviated Journal | Comp Mater Sci |
Volume | 159 | Issue | 159 | Pages | 228-234 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | In this paper we employ first-principles calculations to investigate the effect of substitutional Si doping in the amorphous calcium-phosphate (a-HAP) structure on the work of adhesion, integral charge transfer, charge density difference and theoretical tensile strengths between an a-HAP coating and amorphous titanium dioxide (a-TiO2) substrate systemically. Our calculations demonstrate that substitution of a P atom by a Si atom in a-HAP (a-Si-HAP) with the creation of OH-vacancies as charge compensation results in a significant increase of the bonding strength of the coating to the substrate. The work of adhesion of the optimized Si-doped interfaces reaches a value of up to -2.52 J m(-2), which is significantly higher than for the stoichiometric a-HAP/a-TiO2. Charge density difference analysis indicates that the dominant interactions at the interface have significant covalent character, and in particular two Ti-O and three Ca-O bonds are formed for a-Si-HAP/a-TiO2 and one Ti-O and three Ca-O bonds for a-HAP/a-TiO2. From the stress-strain curve, the Young's modulus of a-Si-HAP/a-TiO2 is calculated to be about 25% higher than that of the a-HAP/a-TiO2, and the yielding stress is about 2 times greater than that of the undoped model. Our calculations therefore demonstrate that the presence of Si in the a-HAP structure strongly alters not only the bioactivity and resorption rates, but also the mechanical properties of the a-HAP/a-TiO2 interface. The results presented here provide an important theoretical insight into the nature of the chemical bonding at the a-HAP/a-TiO2 interface, and are particularly significant for the practical medical applications of HAP-based biomaterials. | ||||
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Language | Wos | 000457856900023 | Publication Date | 2018-12-18 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0927-0256 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.292 | Times cited | 1 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 2.292 | |||
Call Number | UA @ admin @ c:irua:157480 | Serial | 5272 | ||
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Author | Saviuc, I.; Peremans, H.; Van Passel, S.; Milis, K. | ||||
Title | Economic performance of using batteries in European residential microgrids under the net-metering scheme | Type | A1 Journal article | ||
Year | 2019 | Publication | Energies | Abbreviated Journal | Energies |
Volume | 12 | Issue | 1 | Pages | 165-28 |
Keywords | A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) | ||||
Abstract | Decentralized energy production offers an increased share of renewable energy and autonomy compared to the conventional, grid-only solution. However, under the net-metering scheme, the energy losses in batteries translate into financial losses to an investor seeking to move away from grid-only electricity and set up a residential PV+Battery microgrid. Our paper examines a hypothetical support scheme for such a project, designed to balance the economic disadvantage through partially supporting the acquisition of batteries, and thus ensure that the microgrid solution is more attractive than no investment. For this we develop four case studies based on experiments carried out in Greece, Italy, Denmark and Finland. Using the minimization of the Net Present Cost for each project, we compare the PV+Battery solution to the grid-only scenario over 25 years, for a range of electricity prices. The results illustrate first how the success of this project depends on the price of electricity. Second, we find that under current conditions in the respective countries the need for battery support varies between zero in Denmark and 86% in Italy, which reflects how the disadvantages of net metering can only be counterbalanced by either very high electricity price or very high solar resource. Our paper contributes thus to the discussion about the favourable environment for batteries in residential microgrids. | ||||
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Language | Wos | Publication Date | 2019-01-04 | ||
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ISSN | 1996-1073 | ISBN | Additional Links | UA library record | |
Impact Factor | 2.262 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 2.262 | |||
Call Number | UA @ admin @ c:irua:156009 | Serial | 6189 | ||
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Author | Magnus, W.; Brosens, F. | ||||
Title | Occupation numbers in a quantum canonical ensemble : a projection operator approach | Type | A1 Journal article | ||
Year | 2019 | Publication | Physica: A : theoretical and statistical physics | Abbreviated Journal | Physica A |
Volume | 518 | Issue | 518 | Pages | 253-264 |
Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) | ||||
Abstract | Recently, we have used a projection operator to fix the number of particles in a second quantization approach in order to deal with the canonical ensemble. Having been applied earlier to handle various problems in nuclear physics that involve fixed particle numbers, the projector formalism was extended to grant access as well to quantum-statistical averages in condensed matter physics, such as particle densities and correlation functions. In this light, the occupation numbers of the subsequent single-particle energy eigenstates are key quantities to be examined. The goal of this paper is (1) to provide a sound extension of the projector formalism directly addressing the occupation numbers as well as the chemical potential, and (2) to demonstrate how the emerging problems related to numerical instability for fermions can be resolved to obtain the canonical statistical quantities for both fermions and bosons. (C) 2018 Elsevier B.V. All rights reserved. | ||||
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Language | Wos | 000456359200021 | Publication Date | 2018-11-28 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0378-4371 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.243 | Times cited | 1 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.243 | ||
Call Number | UA @ admin @ c:irua:157468 | Serial | 5223 | ||
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Author | de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; de Farias, G.A.; Peeters, F.M. | ||||
Title | Wave packet propagation through branched quantum rings under applied magnetic fields | Type | A1 Journal article | ||
Year | 2019 | Publication | Physica. E: Low-dimensional systems and nanostructures | Abbreviated Journal | Physica E |
Volume | 114 | Issue | 114 | Pages | 113598 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the effect of opening and closing pathways on the dynamics of electron wave packets in semiconductor quantum rings with different geometries. Our analysis is based on the time evolution of an electron wave packet, within the effective-mass approximation. We demonstrate that opening an extra channel in the quantum ring does not necessarily improve the electron transmission and, depending on the extra channel width, may even reduce it, either due to enhancement of quantum scattering or due to interference. In the latter case, transmission reduction can be controlled through the Aharonov-Bohm phase of the wave function, via an applied magnetic field. It is also shown that, closing one of the channels of the quantum ring, system improves the transmission probability under specific conditions, an effect which is a quantum analog of the Braess paradox. | ||||
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Language | Wos | 000482637000039 | Publication Date | 2019-06-13 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1386-9477 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.221 | Times cited | Open Access | ||
Notes | ; This work was financially supported by PRONEX/CNPq/FUNCAP, Science Without Boards (Ciencias Sem Fronteiras) and the bilateral project CNPq-FWO. A. A. Sousa was financially supported by CAPES, under the PDSE contract BEX 7177/ 13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/ 2009 and by CAPES under process BEX 3299/13-9. ; | Approved | Most recent IF: 2.221 | ||
Call Number | UA @ admin @ c:irua:162777 | Serial | 5432 | ||
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Author | Janssens de Bisthoven, L.; Rochette, A.-J.; Verheyen, E.; Akpona, T.J.-D.; Verbist, B.; Vanderhaegen, K.; Naturinda, Z.; Van Passel, S.; Berihun, D.; Munishi, L.; Hugé, J. | ||||
Title | Conserving African biosphere reserves : a workshop on the valuation of ecosystem services in Man and the Biosphere Reserves | Type | A1 Journal article | ||
Year | 2019 | Publication | Oryx | Abbreviated Journal | Oryx |
Volume | 53 | Issue | 4 | Pages | 609 |
Keywords | A1 Journal article; Engineering Management (ENM); Evolutionary ecology group (EVECO) | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2019-10-01 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0030-6053; 1365-3008 | ISBN | Additional Links | UA library record | |
Impact Factor | 2.191 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 2.191 | |||
Call Number | UA @ admin @ c:irua:163043 | Serial | 6172 | ||
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Author | Sun, J.-Y.; Wen, D.-Q.; Zhang, Q.-Z.; Liu, Y.-X.; Wang, Y.-N. | ||||
Title | The effects of electron surface interactions in geometrically symmetric capacitive RF plasmas in the presence of different electrode surface materials | Type | A1 Journal article | ||
Year | 2019 | Publication | Physics of plasmas | Abbreviated Journal | Phys Plasmas |
Volume | 26 | Issue | 6 | Pages | 063505 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Particle-in-cell/Monte Carlo collision (PIC/MCC) simulations are performed to investigate the asymmetric secondary electron emission (SEE) effects when electrons strike two different material electrodes in low pressure capacitively coupled plasmas (CCPs). To describe the electron-surface interactions, a realistic model, considering the primary electron impact energy and angle, as well as the corresponding surface property-dependent secondary electron yields, is employed in PIC/MCC simulations. In this model, three kinds of electrons emitted from the surface are considered: (i) elastically reflected electrons, (ii) inelastically backscattered electrons, and (iii) electron induced secondary electrons (SEs, i.e., delta-electrons). Here, we examined the effects of electron-surface interactions on the ionization dynamics and plasma characteristics of an argon discharge. The discharge is driven by a voltage source of 13.56MHz with amplitudes in the range of 200-2000V. The grounded electrode material is copper (Cu) for all cases, while the powered electrode material is either Cu or silicon dioxide (SiO2). The simulations reveal that the electron impact-induced SEE is an essential process at low pressures, especially at high voltages. Different electrode materials result in an asymmetric response of SEE. Depending on the instantaneous local sheath potential and the phase of the SEE, these SEs either are reflected by the opposite sheath or strike the electrode surface, where they can induce delta-electrons upon their residual energies. It is shown that highly energetic delta-electrons contribute significantly to the ionization rate and a self-bias forms when the powered electrode material is assumed to be made of SiO2. Complex dynamics is observed due to the multiple electron-surface interaction processes and asymmetric yields of SEs in CCPs. | ||||
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Language | Wos | 000474440600043 | Publication Date | 2019-06-06 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1070-664x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.115 | Times cited | 1 | Open Access | |
Notes | Approved | Most recent IF: 2.115 | |||
Call Number | UA @ admin @ c:irua:161353 | Serial | 6327 | ||
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Author | Mohammed, M.; Verhulst, A.S.; Verreck, D.; Van de Put, M.L.; Magnus, W.; Sorée, B.; Groeseneken, G. | ||||
Title | Phonon-assisted tunneling in direct-bandgap semiconductors | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 1 | Pages | 015701 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | In tunnel field-effect transistors, trap-assisted tunneling (TAT) is one of the probable causes for degraded subthreshold swing. The accurate quantum-mechanical (QM) assessment of TAT currents also requires a QM treatment of phonon-assisted tunneling (PAT) currents. Therefore, we present a multi-band PAT current formalism within the framework of the quantum transmitting boundary method. An envelope function approximation is used to construct the electron-phonon coupling terms corresponding to local Frohlich-based phonon-assisted inter-band tunneling in direct-bandgap III-V semiconductors. The PAT current density is studied in up to 100 nm long and 20 nm wide p-n diodes with the 2- and 15-band material description of our formalism. We observe an inefficient electron-phonon coupling across the tunneling junction. We further demonstrate the dependence of PAT currents on the device length, for our non-self-consistent formalism which neglects changes in the electron distribution function caused by the electron-phonon coupling. Finally, we discuss the differences in doping dependence between direct band-to-band tunneling and PAT current. Published under license by AIP Publishing. | ||||
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Language | Wos | 000455350200021 | Publication Date | 2019-01-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 2 | Open Access | |
Notes | ; This work was supported by Imec's Industrial Affiliation Program. ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:156735 | Serial | 5224 | ||
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Author | Milovanović, S.P.; Covaci, L.; Peeters, F.M. | ||||
Title | Strain fields in graphene induced by nanopillar mesh | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 8 | Pages | 082534 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The mechanical and electronic properties of a graphene membrane placed on top of a triangular superlattice of nanopillars are investigated. We use molecular dynamics simulations to access the deformation fields and the tight-binding approaches to calculate the electronic properties. Ripples form in the graphene layer that span across the unit cell, connecting neighboring pillars, in agreement with recent experiments. We find that the resulting pseudo-magnetic field (PMF) varies strongly across the unit cell. We investigate the dependence of PMF on unit cell boundary conditions, height of the pillars, and the strength of the van der Waals interaction between graphene and the substrate. We find direct correspondence with typical experiments on pillars, showing intrinsic “slack” in the graphene membrane. PMF values are confirmed by the local density of states calculations performed at different positions of the unit cell showing pseudo-Landau levels with varying spacings. Our findings regarding the relaxed membrane configuration and the induced strains are transferable to other flexible 2D membranes. | ||||
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Language | Wos | 000460033800038 | Publication Date | 2019-01-16 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 9 | Open Access | |
Notes | ; S.P.M. is supported by the Flemish Science Foundation (FWO). ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:158605 | Serial | 5231 | ||
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Author | Gu, J.-G.; Zhang, Y.; Gao, M.-X.; Wang, H.-Y.; Zhang, Q.-Z.; Yi, L.; Jiang, W. | ||||
Title | Enhancement of surface discharge in catalyst pores in dielectric barrier discharges | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 15 | Pages | 153303 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The generation of high-density plasmas on the surface of porous catalysts is very important for plasma catalysis, as it determines the active surface of the catalyst that is available for the reaction. In this work, we investigate the mechanism of surface and volume plasma streamer formation and propagation near micro-sized pores in dielectric barrier discharges operating in air at atmospheric pressure. A two-dimensional particle-in-cell/ Monte Carlo collision model is used to model the individual kinetic behavior of plasma species. Our calculations indicate that the surface discharge is enhanced on the surface of the catalyst pores compared with the microdischarge inside the catalyst pores. The reason is that the surface ionization wave induces surface charging along the catalyst pore sidewalls, leading to a strong electric field along the pore sidewalls, which in turn further enhances the surface discharge. Therefore, highly concentrated reactive species occur on the surfaces of the catalyst pores, indicating high-density plasmas on the surface of porous catalysts. Indeed, the maximum electron impact excitation and ionization rates occur on the pore surface, indicating the more pronounced production of excited state and electron-ion pairs on the pore surface than inside the pore, which may profoundly affect the plasma catalytic process. Published under license by AIP Publishing. | ||||
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Language | Wos | 000465441200022 | Publication Date | 2019-04-15 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 4 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:160397 | Serial | 5273 | ||
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Author | Vohra, A.; Khanam, A.; Slotte, J.; Makkonen, I.; Pourtois, G.; Loo, R.; Vandervorst, W. | ||||
Title | Evolution of phosphorus-vacancy clusters in epitaxial germanium | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 2 | Pages | 025701 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | The E centers (dopant-vacancy pairs) play a significant role in dopant deactivation in semiconductors. In order to gain insight into dopant-defect interactions during epitaxial growth of in situ phosphorus doped Ge, positron annihilation spectroscopy, which is sensitive to open-volume defects, was performed on Ge layers grown by chemical vapor deposition with different concentrations of phosphorus (similar to 1 x 10(18)-1 x 10(20) cm(-3)). Experimental results supported by first-principles calculations based on the two component density-functional theory gave evidence for the existence of mono-vacancies decorated by several phosphorus atoms as the dominant defect type in the epitaxial Ge. The concentration of vacancies increases with the amount of P-doping. The number of P atoms around the vacancy also increases, depending on the P concentration. The evolution of P-n-V clusters in Ge contributes significantly to the dopant deactivation. Published under license by AIP Publishing. | ||||
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Language | Wos | 000455922100057 | Publication Date | 2019-01-08 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 5 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:156722 | Serial | 5274 | ||
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Author | Piorra, A.; Hrkac, V.; Wolff, N.; Zamponi, C.; Duppel, V.; Hadermann, J.; Kienle, L.; Quandt, E. | ||||
Title | (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 thin films prepared by PLD : relaxor properties and complex microstructure | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 24 | Pages | 244103 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Ferroelectric lead-free thin films of the composition (Ba0.85Ca0.15)(Ti0.9Zr0.1)O-3 (BCZT) were deposited by pulsed laser deposition on Pt/TiO2/SiO2/Si substrates using a ceramic BCZT target prepared by a conventional solid state reaction. The target material itself shows a piezoelectric coefficient of d(33)=640pm/V. The (111) textured thin films possess a thickness of up to 1.1 mu m and exhibit a clamped piezoelectric response f of up to 190pm/V, a dielectric coefficient of (r)=2000 at room temperature, and a pronounced relaxor behavior. As indicated by transmission electron microscopy, the thin films are composed of longitudinal micrometersized columns with similar to 100nm lateral dimension that are separated at twin- and antiphase boundaries. The superposition phenomena according to this columnar growth were simulated based on suitable supercells. The major structural component is described as a tetragonal distorted variant of the perovskite parent type; however, frequently coherently intergrown nanodomains were observed indicating a much more complex structure that is characterized by a 7-layer modulation along the growth direction of the films. | ||||
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Language | Wos | 000474439600002 | Publication Date | 2019-06-25 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | Open Access | ||
Notes | ; The authors want to thank Dr. Martina Luysberg and Dr. Lothar Houben from the Ernst Ruska Centre in Julich for discussion and CS-corrected microscopy. Funding of this work via the DFG (No. CRC1261) “Magnetoelectric Sensors: From Composite Materials to Biomagnetic Diagnostics” and the PAK902 is gratefully acknowledged. ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:161310 | Serial | 5399 | ||
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Author | Chen, Q.; Li, L.L.; Peeters, F.M. | ||||
Title | Inner and outer ring states of MoS2 quantum rings : energy spectrum, charge and spin currents | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 24 | Pages | 244303 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the energy levels and persistent currents of MoS2 quantum rings having different shapes and edge types in the presence of a perpendicular magnetic field by means of the tight-binding approach. We find states localized at the inner and outer boundaries of the ring. These energy levels exhibit different magnetic field dependences for the inner and outer ring states due to their different localization properties. They both exhibit the usual Aharanov-Bohm oscillations but with different oscillation periods. In the presence of spin-orbit coupling, we show distinct spin and charge persistent currents for inner and outer ring states. We find well-defined spin currents with negligibly small charge currents. This is because the local currents of spin-up and -down states flow in opposite directions. | ||||
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Language | Wos | 000474439600026 | Publication Date | 2019-06-25 | |
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ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 11 | Open Access | |
Notes | ; This work was supported by the Hunan Provincial Natural Science Foundation of China (Nos. 2015JJ2040, 2018JJ2080, and 2018JJ4047), the National Natural Science Foundation of China (NNSFC) (No. 51502087), the Scientific Research Fund of Hunan Provincial Education Department (Nos. 15A042, 15B056, and 17B060), and the Flemish Science Foundation (FWO-VI). ; | Approved | Most recent IF: 2.068 | ||
Call Number | UA @ admin @ c:irua:161309 | Serial | 5417 | ||
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Author | Vohra, A.; Khanam, A.; Slotte, J.; Makkonen, I.; Pourtois, G.; Porret, C.; Loo, R.; Vandervorst, W. | ||||
Title | Heavily phosphorus doped germanium : strong interaction of phosphorus with vacancies and impact of tin alloying on doping activation | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 125 | Issue | 22 | Pages | 225703 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We examined the vacancy trapping proficiency of Sn and P atoms in germanium using positron annihilation spectroscopy measurements, sensitive to the open-volume defects. Epitaxial Ge1 xSnx films were grown by chemical vapor deposition with different P concentrations in the 3: 0 1019-1: 5 1020 cm 3 range. We corroborate our findings with first principles simulations. Codoping of Ge with a Sn concentration of up to 9% is not an efficient method to suppress the free vacancy concentration and the formation of larger phosphorus-vacancy complexes. Experimental results confirm an increase in the number of P atoms around the monovacancy with P-doping, leading to dopant deactivation in epitaxial germanium-tin layers with similar Sn content. Vice versa, no impact on the improvement of maximum achieved P activation in Ge with increasing Sn-doping has been observed. Theoretical calculations also confirm that Pn-V (vacancy) complexes are energetically more stable than the corresponding SnmPn-V and Snm-V defect structures with the same number of alien atoms (Sn or P) around the monovacancy. he strong attraction of vacancies to the phosphorus atoms remains the dominant dopant deactivation mechanism in Ge as well as in Ge1 xSnx. Published under license by AIP Publishing. | ||||
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Language | Wos | 000471698600044 | Publication Date | 2019-06-10 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 1 | Open Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:161333 | Serial | 6300 | ||
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Author | Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M. | ||||
Title | Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 126 | Issue | 14 | Pages | 144304 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using first-principles calculations, we study the structural, electronic, and optical properties of pristine BC3. Our results show that BC3 is a semiconductor which can be useful in optoelectronic device applications. Furthermore, we found that the electronic properties of BC3 can be modified by strain and the type of edge states. With increasing thickness, the indirect bandgap decreases from 0.7 eV (monolayer) to 0.27 eV (bulk). Upon uniaxial tensile strain along the armchair and zigzag directions, the bandgap slightly decreases, and with increasing uniaxial strain, the bandgap decreases, and when reaching -8%, a semiconductor-to-metal transition occurs. By contrast, under biaxial strain, the bandgap increases to 1.2 eV in +8% and decreases to zero in -8%. BC3 nanoribbons with different widths exhibit magnetism at the zigzag edges, while, at the armchair edges, they become semiconductor, and the bandgap is in the range of 1.0-1.2 eV. Moreover, we systematically investigated the effects of adatoms/molecule adsorption and defects on the structural, electronic, and magnetic properties of BC3. The adsorption of various adatoms and molecules as well as topological defects (vacancies and Stone-Wales defects) can modify the electronic properties. Using these methods, one can tune BC3 into a metal, half-metal, ferromagnetic-metal, and dilute-magnetic semiconductor or preserve its semiconducting character. Published under license by AIP Publishing. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000503995300019 | Publication Date | 2019-10-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 56 | Open Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:165160 | Serial | 6328 | ||
Permanent link to this record | |||||
Author | Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. | ||||
Title | Two-dimensional carbon nitride (2DCN) nanosheets : tuning of novel electronic and magnetic properties by hydrogenation, atom substitution and defect engineering | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 126 | Issue | 21 | Pages | 215104 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | By employing first-principles calculations within the framework of density functional theory, we investigated the structural, electronic, and magnetic properties of graphene and various two-dimensional carbon-nitride (2DNC) nanosheets. The different 2DCN gives rise to diverse electronic properties such as metals (C3N2), semimetals (C4N and C9N4), half-metals (C4N3), ferromagnetic-metals (C9N7), semiconductors (C2N, C3N, C3N4, C6N6, and C6N8), spin-glass semiconductors (C10N9 and C14N12), and insulators (C2N2). Furthermore, the effects of adsorption and substitution of hydrogen atoms as well as N-vacancy defects on the electronic and magnetic properties are systematically studied. The introduction of point defects, including N vacancies, interstitial H impurity into graphene and different 2DCN crystals, results in very different band structures. Defect engineering leads to the discovery of potentially exotic properties that make 2DCN interesting for future investigations and emerging technological applications with precisely tailored properties. These properties can be useful for applications in various fields such as catalysis, energy storage, nanoelectronic devices, spintronics, optoelectronics, and nanosensors. Published under license by AIP Publishing. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000504007300023 | Publication Date | 2019-12-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 70 | Open Access | |
Notes | Approved | Most recent IF: 2.068 | |||
Call Number | UA @ admin @ c:irua:165733 | Serial | 6329 | ||
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Author | Saniz, R.; Sarmadian, N.; Partoens, B.; Batuk, M.; Hadermann, J.; Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Lamoen, D. | ||||
Title | First-principles study of CO and OH adsorption on in-doped ZnO surfaces | Type | A1 Journal article | ||
Year | 2019 | Publication | The journal of physics and chemistry of solids | Abbreviated Journal | J Phys Chem Solids |
Volume | 132 | Issue | Pages | 172-181 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We present a first-principles computational study of CO and OH adsorption on non-polar ZnO (10¯10) surfaces doped with indium. The calculations were performed using a model ZnO slab. The position of the In dopants was varied from deep bulk-like layers to the surface layers. It was established that the preferential location of the In atoms is at the surface by examining the dependence of the defect formation energy as well as the surface energy on In location. The adsorption sites on the surface of ZnO and the energy of adsorption of CO molecules and OH-species were determined in connection to In doping. It was found that OH has higher bonding energy to the surface than CO. The presence of In atoms at the surface of ZnO is favorable for CO adsorption, resulting in an elongation of the C-O bond and in charge transfer to the surface. The effect of CO and OH adsorption on the electronic and conduction properties of surfaces was assessed. We conclude that In-doped ZnO surfaces should present a higher electronic response upon adsorption of CO. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000472124700023 | Publication Date | 2019-04-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3697 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.059 | Times cited | 7 | Open Access | Not_Open_Access: Available from 26.04.2021 |
Notes | FWO-Vlaanderen, G0D6515N ; ERA.Net RUS Plus, 096 ; VSC; HPC infrastructure of the University of Antwerp; FWO-Vlaanderen; Flemish Government-department EWI; | Approved | Most recent IF: 2.059 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159656 | Serial | 5170 | ||
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Author | De Beule, C.; Saniz, R.; Partoens, B. | ||||
Title | Crystalline topological states at a topological insulator junction | Type | A1 Journal article | ||
Year | 2019 | Publication | The journal of physics and chemistry of solids | Abbreviated Journal | J Phys Chem Solids |
Volume | 128 | Issue | 128 | Pages | 144-151 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We consider an interface between two strong time-reversal invariant topological insulators having surface states with opposite spin chirality, or equivalently, opposite mirror Chern number. We show that such an interface supports gapless modes that are protected by mirror symmetry. The interface states are investigated with a continuum model for the Bi2Se3 class of topological insulators that takes into account terms up to third order in the crystal momentum, which ensures that the model has the correct symmetry. The model parameters are obtained from ab initio calculations. Finally, we consider the effect of rotational mismatch at the interface, which breaks the mirror symmetry and opens a gap in the interface spectrum. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000472693100013 | Publication Date | 2018-01-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3697 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 2.059 | Times cited | Open Access | ||
Notes | ; ; | Approved | Most recent IF: 2.059 | ||
Call Number | UA @ admin @ c:irua:161391 | Serial | 5385 | ||
Permanent link to this record | |||||
Author | Callaert, C.; Bercx, M.; Lamoen, D.; Hadermann, J. | ||||
Title | Interstitial defects in the van der Waals gap of Bi2Se3 | Type | A1 Journal article | ||
Year | 2019 | Publication | Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials (Online) | Abbreviated Journal | Acta Crystallogr B |
Volume | 75 | Issue | 4 | Pages | 717-732 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Bi<sub>2</sub>Se<sub>3</sub>is a thermoelectric material and a topological insulator. It is slightly conducting in its bulk due to the presence of defects and by controlling the defects different physical properties can be fine tuned. However, studies of the defects in this material are often contradicting or inconclusive. Here, the defect structure of Bi<sub>2</sub>Se<sub>3</sub>is studied with a combination of techniques: high-resolution scanning transmission electron microscopy (HR-STEM), high-resolution energy-dispersive X-ray (HR-EDX) spectroscopy, precession electron diffraction tomography (PEDT), X-ray diffraction (XRD) and first-principles calculations using density functional theory (DFT). Based on these results, not only the observed defects are discussed, but also the discrepancies in results or possibilities across the techniques. STEM and EDX revealed interstitial defects with mainly Bi character in an octahedral coordination in the van der Waals gap, independent of the applied sample preparation method (focused ion beam milling or cryo-crushing). The inherent character of these defects is supported by their observation in the structure refinement of the EDT data. Moreover, the occupancy probability of the defects determined by EDT is inversely proportional to their corresponding DFT calculated formation energies. STEM also showed the migration of some atoms across and along the van der Waals gap. The kinetic barriers calculated using DFT suggest that some paths are possible at room temperature, while others are most probably beam induced. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000480512600024 | Publication Date | 2019-08-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2052-5206 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.032 | Times cited | Open Access | ||
Notes | University of Antwerp, 31445 ; Acknowledgements We thank Artem M. Abakumov for providing the original Bi2Se3 sample and are also very grateful to Christophe Vandevelde for trying repeatedly to get good single crystal X-ray diffraction data out of each of our failed attempts at making an undeformed single crystal. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 2.032 | ||
Call Number | EMAT @ emat @c:irua:161847 | Serial | 5295 | ||
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Author | Pittarello, L.; Mckibbin, S.; Yamaguchi, A.; Ji, G.; Schryvers, D.; Debaille, V.; Claeys, P. | ||||
Title | Two generations of exsolution lamellae in pyroxene from Asuka 09545 : Clues to the thermal evolution of silicates in mesosiderite | Type | A1 Journal article | ||
Year | 2019 | Publication | The American mineralogist | Abbreviated Journal | Am Mineral |
Volume | 104 | Issue | 11 | Pages | 1663-1672 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Mesosiderite meteorites consist of a mixture of crustal basaltic or gabbroic material and metal. Their formation process is still debated due to their unexpected combination of crust and core materials, possibly derived from the same planetesimal parent body, and lacking an intervening mantle component. Mesosiderites have experienced an extremely slow cooling rate from ca. 550 degrees C, as recorded in the metal (0.25-0.5 degrees C/Ma). Here we present a detailed investigation of exsolution features in pyroxene from the Antarctic mesosiderite Asuka (A) 09545. Geothermobarometry calculations, lattice parameters, lamellae orientation, and the presence of clinoenstatite as the host were used in an attempt to constrain the evolution of pyroxene from 1150 to 570 degrees C and the formation of two generations of exsolution lamellae. After pigeonite crystallization at ca. 1150 degrees C, the first exsolution process generated the thick augite lamellae along (100) in the temperature interval 1000-900 degrees C. By further cooling, a second order of exsolution lamellae formed within augite along (001), consisting of monoclinic low-Ca pyroxene, equilibrated in the temperature range 900-800 degrees C. The last process, occurring in the 600-500 degrees C temperature range, was likely the inversion of high to low pigeonite in the host crystal, lacking evidence for nucleation of orthopyroxene. The formation of two generations of exsolution lamellae, as well as of likely metastable pigeonite, suggest non-equilibrium conditions. Cooling was sufficiently slow to allow the formation of the lamellae, their preservation, and the transition from high to low pigeonite. In addition, the preservation of such fine-grained lamellae limits long-lasting, impact reheating to a peak temperature lower than 570 degrees C. These features, including the presence of monoclinic low-Ca pyroxene as the host, are reported in only a few mesosiderites. This suggests a possibly different origin and thermal history from most mesosiderites and that the crystallography (i.e., space group) of low-Ca pyroxene could be used as parameter to distinguish mesosiderite populations based on their cooling history. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000494707400014 | Publication Date | 2019-08-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-004x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.021 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 2.021 | |||
Call Number | UA @ admin @ c:irua:164645 | Serial | 6331 | ||
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Author | Nord, M.; Verbeeck, J. | ||||
Title | Towards Reproducible and Transparent Science of (Big) Electron Microscopy Data Using Version Control | Type | P1 Proceeding | ||
Year | 2019 | Publication | Microscopy and microanalysis T2 – Microscopy & Microanalysis 2019, 4-8 August, 2019, Portland, Oregon | Abbreviated Journal | Microsc Microanal |
Volume | 25 | Issue | S2 | Pages | 232-233 |
Keywords | P1 Proceeding; Electron microscopy for materials research (EMAT) | ||||
Abstract | |||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2019-08-05 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1431-9276 | ISBN | Additional Links | UA library record | |
Impact Factor | 1.891 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 1.891 | |||
Call Number | EMAT @ emat @c:irua:164058 | Serial | 5377 | ||
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Author | Nord, M.; Verbeeck, J. | ||||
Title | Open Source Development Tools for Robust and Reproducible Electron Microscopy Data Analysis | Type | P3 | ||
Year | 2019 | Publication | Microscopy And Microanalysis | Abbreviated Journal | Microsc Microanal |
Volume | 25 | Issue | S2 | Pages | 138-139 |
Keywords | P3; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | |||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | Publication Date | 2019-08-05 | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1431-9276 | ISBN | Additional Links | ||
Impact Factor | 1.891 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 1.891 | |||
Call Number | EMAT @ emat @ | Serial | 5378 | ||
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Author | Clima, S.; Garbin, D.; Devulder, W.; Keukelier, J.; Opsomer, K.; Goux, L.; Kar, G.S.; Pourtois, G. | ||||
Title | Material relaxation in chalcogenide OTS SELECTOR materials | Type | A1 Journal article | ||
Year | 2019 | Publication | Microelectronic engineering | Abbreviated Journal | Microelectron Eng |
Volume | 215 | Issue | 215 | Pages | 110996 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Nature of the mobility-gap states in amorphous Ge-rich Ge50Se50 was found to be related to homopolar Ge bonds in the chains/clusters of Ge atoms. Threshold switching material suffers Ge-Ge bond concentration drift during material ageing, which can explain the observed reliability of the aGe(50)Se(50) selector devices. Strong Ge-N bonds were introduced to alleviate the observed instability. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000480665600008 | Publication Date | 2019-05-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0167-9317 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.806 | Times cited | 1 | Open Access | |
Notes | Approved | Most recent IF: 1.806 | |||
Call Number | UA @ admin @ c:irua:161905 | Serial | 6308 | ||
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Author | Buyle, M.; Audenaert, A.; Billen, P.; Boonen, K.; Van Passel, S. | ||||
Title | The future of Ex-Ante LCA? Lessons learned and practical recommendations | Type | A1 Journal article | ||
Year | 2019 | Publication | Sustainability | Abbreviated Journal | Sustainability-Basel |
Volume | 11 | Issue | 19 | Pages | 5456 |
Keywords | A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM); Biochemical Wastewater Valorization & Engineering (BioWaVE); Energy and Materials in Infrastructure and Buildings (EMIB) | ||||
Abstract | Every decision-oriented life cycle assessment (LCAs) entails, at least to some extent, a future-oriented feature. However, apart from the ex-ante LCAs, the majority of LCA studies are retrospective in nature and do not explicitly account for possible future effects. In this review a generic theoretical framework is proposed as a guideline for ex-ante LCA. This framework includes the entire technology life cycle, from the early design phase up to continuous improvements of mature technologies, including their market penetration. The compatibility with commonly applied system models yields an additional aspect of the framework. Practical methods and procedures are categorised, based on how they incorporate future-oriented features in LCA. The results indicate that most of the ex-ante LCAs focus on emerging technologies that have already gone through some research cycles within narrowly defined system boundaries. There is a lack of attention given to technologies that are at a very early development stage, when all options are still open and can be explored at a low cost. It is also acknowledged that technological learning impacts the financial and environmental performance of mature production systems. Once technologies are entering the market, shifts in market composition can lead to substantial changes in environmental performance. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000493525500315 | Publication Date | 2019-10-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2071-1050 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles | |
Impact Factor | 1.789 | Times cited | 4 | Open Access | |
Notes | ; Thanks to Koen Breemersch for providing insightful and useful comments on draft versions of this manuscript. This work was supported by the University of Antwerp and the Flemish Institute for Technological Research (VITO). The authors also acknowledge anonymous reviewers for the constructive suggestions and the stimulating discussion. ; | Approved | Most recent IF: 1.789 | ||
Call Number | UA @ admin @ c:irua:162571 | Serial | 6205 | ||
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Author | Dhayalan, S.K.; Nuytten, T.; Pourtois, G.; Simoen, E.; Pezzoli, F.; Cinquanta, E.; Bonera, E.; Loo, R.; Rosseel, E.; Hikavyy, A.; Shimura, Y.; Vandervorst, W. | ||||
Title | Insights into the C Distribution in Si:C/Si:C:P and the Annealing Behavior of Si:C Layers | Type | A1 Journal article | ||
Year | 2019 | Publication | ECS journal of solid state science and technology | Abbreviated Journal | Ecs J Solid State Sc |
Volume | 8 | Issue | 4 | Pages | P209-P216 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Si:C and Si:C:P alloys are potential candidates for source-drain stressor applications in n-type Fin Field Effect Transistors (FinFETs). Increasing the C content to achieve high strain results in the arrangement of C atoms as third nearest neighbors (3nn) in the Si: C lattice. During thermal annealing, the presence of C atoms as 3nn may promote clustering at the interstitial sites, causing loss of stress. The concentration of C atoms as 3nn is reduced by the incorporation of a small amount of Ge atoms during the growth, whereas in-situ P doping does not influence this 3nn distribution [J Solid State Sci. Technol vol 6, p 755, 2017]. Small amounts of Ge are provided during low temperature selective epitaxial growth scheme, which are based on cyclic deposition and etching (CDE). In this work, we aim to provide physical insights into the aforementioned phenomena, to understand the behavior of 3nn C atoms and the types of defects that are formed in the annealed Si: C films. Using ab-initio simulations, the Ge-C interaction in the Si matrix is investigated and this insight is used to explain how the Ge incorporation leads to a reduced 3nn distribution of the C atoms. The interaction between C and P in the Si: C: P films is also investigated to explain why the P incorporation has not led to a reduction in the 3nn distribution. We then report on the Raman characterization of Si: C layers subjected to post epi annealing. As the penetration depth of the laser is dependent on the wavelength, Raman measurements at two different wavelengths enable us to probe the depth distribution of 3nn C atoms after applying different annealing conditions. We observed a homogeneous loss in 3nn C throughout the layer. Whereas in the kinematic modeling of high resolution X-ray diffraction spectra, a gradient in the substitutional C loss was observed close to the epitaxial layer/substrate interface. This gradient can be due to the out diffusion of C atoms into the Si substrate or to the formation of interstitial C clusters, which cannot be distinguished in HR-XRD. Deep Level Transient Spectroscopy indicated that the prominent out-diffusing species was interstitial CO complex while the interstitial C defects were also prevalent in the epi layer. (c) 2019 The Electrochemical Society. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000465069200001 | Publication Date | 2019-04-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2162-8769; 2162-8777 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 1.787 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 1.787 | |||
Call Number | UA @ admin @ c:irua:160399 | Serial | 5275 | ||
Permanent link to this record | |||||
Author | Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F.; Peeters, F.M. | ||||
Title | Adsorption of molecules on C3N nanosheet : a first-principles calculations | Type | A1 Journal article | ||
Year | 2019 | Publication | Chemical physics | Abbreviated Journal | Chem Phys |
Volume | 526 | Issue | 526 | Pages | 110442 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using first-principles calculations we investigate the interaction of various molecules, including H-2, N-2, CO, CO2, H2O, H2S, NH3, CH4 with a C3N nanosheet. Due to the weaker interaction between H-2, N-2, CO, CO2, H2O, H2S, NH3, and CH4 molecules with C3N, the adsorption energy is small and does not yield any significant distortion of the C3N lattice and the molecules are physisorbed. Calculated charge transfer shows that these molecules act as weak donors. However, adsorption of O-2, NO, NO2 and SO2 molecules are chemisorbed, they receive electrons from C3N and act as a strong acceptor. They interact strongly through hybridizing its frontier orbitals with the p-orbital of C3N, modifying the electronic structure of C3N. Our theoretical studies indicate that C3N-based sensor has a high potential for O-2, NO, NO2 and SO2 molecules detection. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000481606000006 | Publication Date | 2019-07-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0301-0104 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.767 | Times cited | 52 | Open Access | |
Notes | ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). In addition, this work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 1.767 | ||
Call Number | UA @ admin @ c:irua:161779 | Serial | 5405 | ||
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Author | Gezahegn, T.W.; Van Passel, S.; Berhanu, T.; D'Haese, M.; Maertens, M. | ||||
Title | Big is efficient : evidence from agricultural cooperatives in Ethiopia | Type | A1 Journal article | ||
Year | 2019 | Publication | Agricultural Economics | Abbreviated Journal | Agr Econ-Blackwell |
Volume | 50 | Issue | 50 | Pages | 555-566 |
Keywords | A1 Journal article; Economics; Engineering Management (ENM) | ||||
Abstract | In Ethiopia, there is a renewed interest in agricultural cooperatives as an institutional tool to improve the welfare of smallholder farmers. One of the pathways through which cooperatives benefit their members is scale economies. However, the establishment of cooperatives in Ethiopia seems to pay little attention to the size of the organizations. This article aims at investigating the effect of size on cost efficiency of agricultural cooperatives. More specifically, the purpose is to examine whether a single cooperative can serve a given number of farmers at a lower cost than two or more smaller cooperatives could. We employ the concept of cost subadditivity to compare the cost efficiency of large versus small cooperatives, and by extension unilateral actions. We estimate a flexible production technology using cross-sectional cooperative-level data. Findings show that costs would drop by 78% to 181% if farmers join hands in relatively large rather than small cooperatives. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000480797700001 | Publication Date | 2019-08-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0169-5150 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 1.758 | Times cited | Open Access | ||
Notes | ; VLIR-UOS-ZEIN2015PR406 (13V95615T) PROGRAMME(TEAM), Belgium ; | Approved | Most recent IF: 1.758 | ||
Call Number | UA @ admin @ c:irua:161812 | Serial | 6161 | ||
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Author | Guzzinati, G.; Béché, A.; McGrouther, D.; Verbeeck, J. | ||||
Title | Prospects for out-of-plane magnetic field measurements through interference of electron vortex modes in the TEM | Type | A1 Journal article | ||
Year | 2019 | Publication | Journal of optics | Abbreviated Journal | J Optics-Uk |
Volume | 21 | Issue | 12 | Pages | 124002 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Magnetic field mapping in transmission electron microscopy is commonplace, but all conventional methods provide only a projection of the components of the magnetic induction perpendicular to the electron trajectory. Recent experimental advances with electron vortices have shown that it is possible to map the out of plane magnetic induction in a TEM setup via interferometry with a specifically prepared electron vortex state carrying high orbital angular momentum (OAM). The method relies on the Aharonov?Bohm phase shift that the electron undergoes when going through a longitudinal field. Here we show how the same effect naturally occurs for any electron wave function, which can always be described as a superposition of OAM modes. This leads to a clear connection between the occurrence of high-OAM partial waves and the amount of azimuthal rotation in the far field angular distribution of the beam. We show that out of plane magnetic field measurement can thus be obtained with a much simpler setup consisting of a ring-like aperture with azimuthal spokes. We demonstrate the experimental setup and explore the achievable sensitivity of the magnetic field measurement. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000499367800001 | Publication Date | 2019-10-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-8978 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.741 | Times cited | 3 | Open Access | |
Notes | The authors thank V Grillo and T Harvey for interesting and fruitful discussion. GG acknowledges support from a postdoctoral fellow-ship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. AB acknowledges funding from FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy'). DM gratefully acknowledges funding of the FEBID capability through joint funding by University of Glasgow & EPSRC through a Strategic Equipment Grant (EP/P001483/1). | Approved | Most recent IF: 1.741 | ||
Call Number | UA @ admin @ c:irua:165116 | Serial | 6319 | ||
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Author | Bogaerts, A.; Yusupov, M.; Razzokov, J.; Van der Paal, J. | ||||
Title | Plasma for cancer treatment: How can RONS penetrate through the cell membrane? Answers from computer modeling | Type | A1 Journal article | ||
Year | 2019 | Publication | Frontiers of Chemical Science and Engineering | Abbreviated Journal | Front Chem Sci Eng |
Volume | Issue | Pages | |||
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Plasma is gaining increasing interest for cancer treatment, but the underlying mechanisms are not yet fully understood. Using computer simulations at the molecular level, we try to gain better insight in how plasma-generated reactive oxygen and nitrogen species (RONS) can penetrate through the cell membrane. Specifically, we compare the permeability of various (hydrophilic and hydrophobic) RONS across both oxidized and nonoxidized cell membranes. We also study pore formation, and how it is hampered by higher concentrations of cholesterol in the cell membrane, and we illustrate the much higher permeability of H2O2 through aquaporin channels. Both mechanisms may explain the selective cytotoxic effect of plasma towards cancer cells. Finally, we also discuss the synergistic effect of plasma-induced oxidation and electric fields towards pore formation. Keywords plasma medicine, cancer treatment, computer modelling, cell membrane, reactive oxygen and nitrogen species |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000468848400004 | Publication Date | 2019-03-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2095-0179 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.712 | Times cited | 5 | Open Access | Not_Open_Access: Available from 23.05.2020 |
Notes | We acknowledge financial support from the Research Foundation–Flanders (FWO; Grant Nos. 1200216N and 11U5416N). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. We are also very thankful to R. Cordeiro for the very interesting discussions. | Approved | Most recent IF: 1.712 | ||
Call Number | PLASMANT @ plasmant @UA @ admin @ c:irua:159977 | Serial | 5172 | ||
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Author | Brault, P.; Chamorro-Coral, W.; Chuon, S.; Caillard, A.; Bauchire, J.-M.; Baranton, S.; Coutanceau, C.; Neyts, E. | ||||
Title | Molecular dynamics simulations of initial Pd and PdO nanocluster growth in a magnetron gas aggregation source | Type | A1 Journal article | ||
Year | 2019 | Publication | Frontiers of Chemical Science and Engineering | Abbreviated Journal | Front Chem Sci Eng |
Volume | 13 | Issue | 2 | Pages | 324-329 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Molecular dynamics simulations are carried out for describing growth of Pd and PdO nanoclusters using the ReaxFF force field. The resulting nanocluster structures are successfully compared to those of nanoclusters experimentally grown in a gas aggregation source. The PdO structure is quasi-crystalline as revealed by high resolution transmission microscope analysis for experimental PdO nanoclusters. The role of the nanocluster temperature in the molecular dynamics simulated growth is highlighted. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000468848400009 | Publication Date | 2019-03-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2095-0179 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.712 | Times cited | 3 | Open Access | Not_Open_Access |
Notes | Approved | Most recent IF: 1.712 | |||
Call Number | UA @ admin @ c:irua:160278 | Serial | 5276 | ||
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Author | Neyts, E.C. | ||||
Title | Special Issue on future directions in plasma nanoscience | Type | Editorial | ||
Year | 2019 | Publication | Frontiers of Chemical Science and Engineering | Abbreviated Journal | Front Chem Sci Eng |
Volume | 13 | Issue | 2 | Pages | 199-200 |
Keywords | Editorial; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | |||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000468848400001 | Publication Date | 2019-05-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2095-0179 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.712 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 1.712 | |||
Call Number | UA @ admin @ c:irua:160277 | Serial | 5280 | ||
Permanent link to this record |