|   | 
Details
   web
Records
Author Coulombier, M.; Baral, P.; Orekhov, A.; Dohmen, R.; Raskin, J.P.; Pardoen, T.; Cordier, P.; Idrissi, H.
Title On-chip very low strain rate rheology of amorphous olivine films Type A1 Journal article
Year 2024 Publication Acta materialia Abbreviated Journal
Volume 266 Issue Pages 119693-12
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Recent observations made by the authors revealed the activation of stress induced amorphization and sliding at grain boundary in olivine [1], a mechanism which is expected to play a pivotal role in the viscosity drop at the lithosphere-asthenosphere boundary and the brittle -ductile transition in the lithospheric mantle. However, there is a lack of information in the literature regarding the intrinsic mechanical properties and the elementary deformation mechanisms of this material, especially at time scales relevant for geodynamics. In the present work, amorphous olivine films were obtained by pulsed laser deposition (PLD). The mechanical response including the rate dependent behavior are investigated using a tension -on -chip (TOC) method developed at UCLouvain allowing to perform creep/relaxation tests on thin films at extremely low strain rates. In the present work, strain rate down to 10-12 s- 1 was reached which is unique. High strain rate sensitivity of 0.054 is observed together with the activation of relaxation at the very early stage of deformation. Furthermore, digital image correlation (DIC), used for the first time on films deformed by TOC, reveals local strain heterogeneities. The relationship between such heterogeneities, the high strain rate sensitivity and the effect of the electron beam in the scanning electron microscope is discussed and compared to the literature.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001170513400001 Publication Date 2024-01-17
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1359-6454 ISBN Additional Links UA library record; WoS full record
Impact Factor 9.4 Times cited Open Access
Notes Approved Most recent IF: 9.4; 2024 IF: 5.301
Call Number UA @ admin @ c:irua:204864 Serial 9163
Permanent link to this record
 

 
Author Joy, R.M.; Pobedinskas, P.; Bourgeois, E.; Chakraborty, T.; Goerlitz, J.; Herrmann, D.; Noel, C.; Heupel, J.; Jannis, D.; Gauquelin, N.; D'Haen, J.; Verbeeck, J.; Popov, C.; Houssiau, L.; Becher, C.; Nesladek, M.; Haenen, K.
Title Photoluminescence of germanium-vacancy centers in nanocrystalline diamond films : implications for quantum sensing applications Type A1 Journal article
Year 2024 Publication ACS applied nano materials Abbreviated Journal
Volume 7 Issue 4 Pages 3873-3884
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Point defects in diamond, promising candidates for nanoscale pressure- and temperature-sensing applications, are potentially scalable in polycrystalline diamond fabricated using the microwave plasma-enhanced chemical vapor deposition (MW PE CVD) technique. However, this approach introduces residual stress in the diamond films, leading to variations in the characteristic zero phonon line (ZPL) of the point defect in diamond. Here, we report the effect of residual stress on germanium-vacancy (GeV) centers in MW PE CVD nanocrystalline diamond (NCD) films fabricated using single crystal Ge as the substrate and solid dopant source. GeV ensemble formation indicated by the zero phonon line (ZPL) at similar to 602 nm is confirmed by room temperature (RT) photoluminescence (PL) measurements. PL mapping results show spatial nonuniformity in GeV formation along with other defects, including silicon-vacancy centers in the diamond films. The residual stress in NCD results in shifts in the PL peak positions. By estimating a stress shift coefficient of (2.9 +/- 0.9) nm/GPa, the GeV PL peak position in the NCD film is determined to be between 598.7 and 603.2 nm. A larger ground state splitting due to the strain on a GeV-incorporated NCD pillar at a low temperature (10 K) is also reported. We also report the observation of intense ZPLs at RT that in some cases could be related to low Ge concentration and the surrounding crystalline environment. In addition, we also observe thicker microcrystalline diamond (MCD) films delaminate from the Ge substrate due to film residual stress and graphitic phase at the diamond/Ge substrate interface (confirmed by electron energy loss spectroscopy). Using this approach, a free-standing color center incorporated MCD film with dimensions up to 1 x 1 cm(2) is fabricated. Qualitative analysis using time-of-flight secondary ion mass spectroscopy reveals the presence of impurities, including Ge and silicon, in the MCD film. Our experimental results will provide insights into the scalability of GeV fabrication using the MW PE CVD technique and effectively implement NCD-based nanoscale-sensing applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001164609600001 Publication Date 2024-02-15
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2574-0970 ISBN Additional Links UA library record; WoS full record
Impact Factor 5.9 Times cited Open Access
Notes Approved Most recent IF: 5.9; 2024 IF: NA
Call Number UA @ admin @ c:irua:204826 Serial 9164
Permanent link to this record
 

 
Author Fang, W.; Wang, X.; Li, S.; Hao, Y.; Yang, Y.; Zhao, W.; Liu, R.; Li, D.; Li, C.; Gao, X.; Wang, L.; Guo, H.; Yi, Y.
Title Plasma-catalytic one-step steam reforming of CH₄ to CH₃OH and H₂ promoted by oligomerized [Cu-O-Cu] species on zeolites Type A1 Journal article
Year 2024 Publication Green chemistry : cutting-edge research for a greener sustainable future Abbreviated Journal
Volume 26 Issue 9 Pages 5150-5154
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Oligomerized [Cu-O-Cu] species are reported to be efficient in promoting plasma catalytic one-step steam reforming of methane to methanol and hydrogen, achieving 6.8% CH4 conversion and 73.1% CH3OH selectivity without CO2.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001195192800001 Publication Date 2024-04-02
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9262; 1463-9270 ISBN Additional Links UA library record; WoS full record
Impact Factor 9.8 Times cited Open Access
Notes Approved Most recent IF: 9.8; 2024 IF: 9.125
Call Number UA @ admin @ c:irua:205514 Serial 9165
Permanent link to this record
 

 
Author Long, Y.; Wang, X.; Zhang, H.; Wang, K.; Ong, W.-L.; Bogaerts, A.; Li, K.; Lu, C.; Li, X.; Yan, J.; Tu, X.; Zhang, H.
Title Plasma chemical looping : unlocking high-efficiency CO₂ conversion to clean CO at mild temperatures Type A1 Journal article
Year 2024 Publication JACS Au Abbreviated Journal
Volume Issue Pages
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We propose a plasma chemical looping CO2 splitting (PCLCS) approach that enables highly efficient CO2 conversion into O-2-free CO at mild temperatures. PCLCS achieves an impressive 84% CO2 conversion and a 1.3 mmol g(-1) CO yield, with no O-2 detected. Crucially, this strategy significantly lowers the temperature required for conventional chemical looping processes from 650 to 1000 degrees C to only 320 degrees C, demonstrating a robust synergy between plasma and the Ce0.7Zr0.3O2 oxygen carrier (OC). Systematic experiments and density functional theory (DFT) calculations unveil the pivotal role of plasma in activating and partially decomposing CO2, yielding a mixture of CO, O-2/O, and electronically/vibrationally excited CO2*. Notably, these excited CO2* species then efficiently decompose over the oxygen vacancies of the OCs, with a substantially reduced activation barrier (0.86 eV) compared to ground-state CO2 (1.63 eV), contributing to the synergy. This work offers a promising and energy-efficient pathway for producing O-2-free CO from inert CO2 through the tailored interplay of plasma and OCs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001225139200001 Publication Date 2024-05-08
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:205970 Serial 9166
Permanent link to this record
 

 
Author Lu, Q.
Title Precipitation behavior and heat resistance properties of Al-Cu-Mg-Ag-(Si) alloy Type Doctoral thesis
Year 2024 Publication Abbreviated Journal
Volume Issue Pages VIII, 212 p.
Keywords Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract With the rapid increase in the speed of new-generation aerospace vehicles, conventional heat-resistant aluminum alloys cannot meet the long-term service of the equipment. Therefore, the development of new high-strength heat-resistant aluminum alloys is of great strategic for the sustainable and high-quality development of industries. Al-Cu-Mg-Ag alloy is an age-hardenable heat-resistant aluminum alloy and has high strength and heat resistance. The addition of alloying elements such as Si and Sc to Al-Cu-Mg-Ag alloy introduces a competitive relationship among the σ-Al5Cu6Mg2, θ′-Al2Cu, and Ω phases. Therefore, a systematic investigation of precipitation behavior and heat resistance of Al-Cu-Mg-Ag-(Si) is essential for guiding the design of high-strength heat-resistant aluminum alloys. Combined characterization testing methods such as scanning electron microscopy, transmission electron microscopy, atom probe tomography, microhardness testing, and tensile testing with simulation calculation methods such as calculation of phase diagram, first-principles calculations, and Ab initio molecular dynamics, the effects of heat treatment processes and element content on the precipitation behavior, mechanical properties, and heat resistance of Al-Cu-Mg-Ag-(Si) alloys were systematically investigated. Furthermore, a multiple interface segregation structure was constructed at the θ′/Al interface, and a new Al-Cu-Mg-Ag-Si-Sc alloy with synergistically improved strength and heat resistance was developed. The main conclusions are as follows: (1) Based on the Kampmann-Wagner-Numerical theory, the relationship between the coarsening rate of the Ω phase and the aging process was analyzed, revealing for the first time that the critical size of Ω phase ( ) under thermal exposure temperature was the key factor determining the coarsening rate of Ω phase during long time thermal exposure heat treatment. After artificial ageing, when the size of Ω phase was smaller than the critical size , the dissolution of smaller Ω phase leaded to a rapid decrease in the number density of Ω phases, thereby reducing the heat resistance of the alloy. When the size of Ω phase was greater than or equal to the critical size , the coarsening rate of Ω phase was consistent, but a larger initial size would result in a larger final size after long-term thermal exposure. Therefore, the closer the size of Ω phase in the alloy is to the critical size under heat exposure temperature, the better the heat resistance of the alloy. (2) A concept of constructing a multiple interface segregation structure at the precipitate/matrix interface was proposed, and based on this concept, a multiple interface segregation structure containing the C/L-AlMgSiCu interfacial phase, newly discovered χ-AgMg interfacial phase, and Sc segregation layer was successfully constructed at the θ′/Al interface. The existence of the multiple interface segregation structure ensured that the designed Al-Cu-Mg-Ag-Si-Sc alloy maintains a yield strength of 400 MPa after thermal exposure at 200 C for 100 h, with a strength retention rate of 97%, creating a new record for the synergistic improvement of strength and heat resistance in aluminum alloys. In addition, combining transmission electron microscopy ex-situ/in-situ characterization with first-principles calculations, it is shown that the χ-AgMg interface phase will be destroyed due to the diffusion of the outer Ag layer during thermal exposure, and gradually dissolve into the matrix, but it can still delay the coarsening behavior of θ′-Al2Cu phase. (3) The criteria for determining whether Ω phase can precipitate are updated in Al-Cu-Mg-Ag-Si alloys with low Mg/Si ratio based on phase diagram thermodynamic calculations and multi-scale structural characterization. When W(Mg)/W(Si) > 1.4 and X(Ag)/X(Mgexcess) > 1, Ω phase can precipitate in Al-Cu-Mg-Ag-Si alloys, where X(Mgexcess) represents the atomic percentage of residual Mg elements after the formation of the AlMgSiCu quaternary precipitate phase C/L phase in the supersaturated solid solution, and the W(Mg) is the mass fraction of Mg in the supersaturated solid solution before artificial ageing. (4) The effects of alloy element content on precipitation behavior and heat resistance of Al-Cu-Mg-Ag-Si alloys were systematically analyzed. Critical conditions for the precipitation of σ-Al5Cu6Mg2 and Ω phase in Al-Cu-Mg-Ag-Si alloys are revealed. Based on calculation of phase diagram results, the conditions for precipitating σ-Al5Cu6Mg2 phase in the alloy are: ① W(Mg)/W(Si) > 1.8; ② W(Cu) > 2.7W(Mg) – 5W(Si). When W(Mg)/W(Si) < 1.8, the alloy is mainly precipitated with C/L/Q′-AlMgSiCu. When W(Cu) < 2.7W(Mg) – 5W(Si), the alloy will generate GPB zone. In addition, W(Ag)/W(Si) > 4 is the critical condition which the Ω phase can the main precipitates in Al-Cu-Mg-Ag-Si alloys. Furthermore, the correlation between precipitate types and heat resistance was summarized, showing that Al-Cu-Mg-Ag-(Si) alloys with Ω phase as the main strengthening phase are more suitable for the preparation of structures with short service time but high temperature, while Al-Cu-Mg-Ag-(Si) alloys with low Mg content and multiple segregation structures are more suitable for structures requiring long-term service at medium to high temperatures. This study, for the first time, combines calculation of phase diagram with multi-scale microstructure characterization, systematically unraveling the effects of element content on precipitation behavior, strength, and heat resistance of Al-Cu-Mg-Ag-(Si) alloys. In addition, a concept of constructing a multiple interface segregation structure at the precipitate/matrix interface was proposed to synergistically improve alloy strength and heat resistance. This work provides theoretical guidance for optimizing the composition and processing of Al-Cu-Mg-Ag-(Si) alloy and regulating the microstructure. Furthermore, it also offers new ideas and theoretical guidance for the development of novel high-strength heat-resistant alloys in other systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:206180 Serial 9167
Permanent link to this record
 

 
Author Gogoi, A.; Neyts, E.C.; Peeters, F.M.
Title Reduction-enhanced water flux through layered graphene oxide (GO) membranes stabilized with H3O+ and OH- ions Type A1 Journal article
Year 2024 Publication Physical chemistry, chemical physics Abbreviated Journal
Volume 26 Issue 13 Pages 10265-10272
Keywords A1 Journal article; Condensed Matter Theory (CMT); Modelling and Simulation in Chemistry (MOSAIC)
Abstract Graphene oxide (GO) is one of the most promising candidates for next generation of atomically thin membranes. Nevertheless, one of the major issues for real world application of GO membranes is their undesirable swelling in an aqueous environment. Recently, we demonstrated that generation of H3O+ and OH- ions (e.g., with an external electric field) in the interlayer gallery could impart aqueous stability to the layered GO membranes (A. Gogoi, ACS Appl. Mater. Interfaces, 2022, 14, 34946). This, however, compromises the water flux through the membrane. In this study, we report on reducing the GO nanosheets as a solution to this issue. With the reduction of the GO nanosheets, the water flux through the layered GO membrane initially increases and then decreases again beyond a certain degree of reduction. Here, two key factors are at play. Firstly, the instability of the H-bond network between water molecules and the GO nanosheets, which increases the water flux. Secondly, the pore size reduction in the interlayer gallery of the membranes, which decreases the water flux. We also observe a significant improvement in the salt rejection of the membranes, due to the dissociation of water molecules in the interlayer gallery. In particular, for the case of 10% water dissociation, the water flux through the membranes can be enhanced without altering its selectivity. This is an encouraging observation as it breaks the traditional tradeoff between water flux and salt rejection of a membrane.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001186465400001 Publication Date 2024-03-15
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.3 Times cited Open Access
Notes Approved Most recent IF: 3.3; 2024 IF: 4.123
Call Number UA @ admin @ c:irua:204792 Serial 9168
Permanent link to this record
 

 
Author Tiwari, S.; Van de Put, M.; Sorée, B.; Hinkle, C.; Vandenberghe, W.G.
Title Reduction of magnetic interaction due to clustering in doped transition-metal dichalcogenides : a case study of Mn-, V-, and Fe-doped WSe₂ Type A1 Journal article
Year 2024 Publication ACS applied materials and interfaces Abbreviated Journal
Volume 16 Issue 4 Pages 4991-4998
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Using Hubbard-U-corrected density functional theory calculations, lattice Monte Carlo simulations, and spin Monte Carlo simulations, we investigate the impact of dopant clustering on the magnetic properties of WSe2 doped with period four transition metals. We use manganese (Mn) and iron (Fe) as candidate n-type dopants and vanadium (V) as the candidate p-type dopant, substituting the tungsten (W) atom in WSe2. Specifically, we determine the strength of the exchange interaction in Fe-, Mn-, and V-doped WSe2 in the presence of clustering. We show that the clusters of dopants are energetically more stable than discretely doped systems. Further, we show that in the presence of dopant clustering, the magnetic exchange interaction significantly reduces because the magnetic order in clustered WSe2 becomes more itinerant. Finally, we show that the clustering of the dopant atoms has a detrimental effect on the magnetic interaction, and to obtain an optimal Curie temperature, it is important to control the distribution of the dopant atoms.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001155511900001 Publication Date 2024-01-18
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1944-8244 ISBN Additional Links UA library record; WoS full record
Impact Factor 9.5 Times cited Open Access
Notes Approved Most recent IF: 9.5; 2024 IF: 7.504
Call Number UA @ admin @ c:irua:203830 Serial 9169
Permanent link to this record
 

 
Author Poppe, R.; Roth, N.; Neder, R.B.; Palatinus, L.; Iversen, B.B.; Hadermann, J.
Title Refining short-range order parameters from the three-dimensional diffuse scattering in single-crystal electron diffraction data Type A1 Journal article
Year 2024 Publication IUCrJ Abbreviated Journal
Volume 11 Issue 1 Pages 82-91
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Our study compares short-range order parameters refined from the diffuse scattering in single-crystal X-ray and single-crystal electron diffraction data. Nb0.84CoSb was chosen as a reference material. The correlations between neighbouring vacancies and the displacements of Sb and Co atoms were refined from the diffuse scattering using a Monte Carlo refinement in DISCUS. The difference between the Sb and Co displacements refined from the diffuse scattering and the Sb and Co displacements refined from the Bragg reflections in single-crystal X-ray diffraction data is 0.012 (7) angstrom for the refinement on diffuse scattering in single-crystal X-ray diffraction data and 0.03 (2) angstrom for the refinement on the diffuse scattering in single-crystal electron diffraction data. As electron diffraction requires much smaller crystals than X-ray diffraction, this opens up the possibility of refining short-range order parameters in many technologically relevant materials for which no crystals large enough for single-crystal X-ray diffraction are available.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001168018300012 Publication Date 2023-12-14
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2052-2525 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.9 Times cited Open Access
Notes Approved Most recent IF: 3.9; 2024 IF: 5.793
Call Number UA @ admin @ c:irua:205513 Serial 9170
Permanent link to this record
 

 
Author Sethu, K.K.V.; Yasin, F.; Swerts, J.; Sorée, B.; De Boeck, J.; Kar, G.S.; Garello, K.; Couet, S.
Title Spin-orbit torque vector quantification in nanoscale magnetic tunnel junctions Type A1 Journal article
Year 2024 Publication ACS nano Abbreviated Journal
Volume 18 Issue 21 Pages 13506-13516
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Spin-orbit torques (SOT) allow ultrafast, energy-efficient toggling of magnetization state by an in-plane charge current for applications such as magnetic random-access memory (SOT-MRAM). Tailoring the SOT vector comprising of antidamping (T-AD) and fieldlike (T-FL) torques could lead to faster, more reliable, and low-power SOT-MRAM. Here, we establish a method to quantify the longitudinal (T-AD) and transverse (T-FL) components of the SOT vector and its efficiency chi(AD) and chi(FL), respectively, in nanoscale three-terminal SOT magnetic tunnel junctions (SOT-MTJ). Modulation of nucleation or switching field (B-SF) for magnetization reversal by SOT effective fields (B-SOT) leads to the modification of SOT-MTJ hysteresis loop behavior from which chi(AD) and chi(FL) are quantified. Surprisingly, in nanoscale W/CoFeB SOT-MTJ, we find chi(FL) to be (i) twice as large as chi(AD) and (ii) 6 times as large as chi(FL) in micrometer-sized W/CoFeB Hall-bar devices. Our quantification is supported by micromagnetic and macrospin simulations which reproduce experimental SOT-MTJ Stoner-Wohlfarth astroid behavior only for chi(FL) > chi(AD). Additionally, from the threshold current for current-induced magnetization switching with a transverse magnetic field, we show that in SOT-MTJ, T-FL plays a more prominent role in magnetization dynamics than T-AD. Due to SOT-MRAM geometry and nanodimensionality, the potential role of nonlocal spin Hall spin current accumulated adjacent to the SOT-MTJ in the mediation of T-FL and chi(FL) amplification merits to be explored.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001226121700001 Publication Date 2024-05-15
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record
Impact Factor 17.1 Times cited Open Access
Notes Approved Most recent IF: 17.1; 2024 IF: 13.942
Call Number UA @ admin @ c:irua:205980 Serial 9173
Permanent link to this record
 

 
Author Manaigo, F.
Title Study of a gliding arc discharge for sustainable nitrogen fixation into NOx Type Doctoral thesis
Year 2024 Publication Abbreviated Journal
Volume Issue Pages xxiv, 114 p.
Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract With the growth of the world population, the agricultural sector is required to meet an increasing demand for nutrients and currently relies on industrially produced fertilizers. Among them, nitrogen-based fertilizers are the most common choice and require N2 to be converted into more reactive molecules in a process called “nitrogen fixation”. This is mainly performed through the Haber-Bosch process, which, is not ideal since it requires large-scale facilities to be economical and is associated with a high energy cost and high CO2 emissions, resulting in an environmental impact that is pushing for the study of greener alternatives. Among these, plasma-based nitrogen fixation into NOx is promising, and gliding arc plasma, specifically, proved to be suitable for nitrogen fixation. This thesis aims to study plasma-based nitrogen fixation focusing on an atmospheric pressure gliding arc plasma on three different levels. On a fundamental level, an approach dealing with laser-based excitation of separate rotational lines was successfully developed. This method can be implemented on atmospheric discharges that produce rather high NOx densities and, thus, can impose essential restrictions for the use of “classical” laser-induced fluorescence methods. The approach is then implemented, providing a discussion on the two-dimensional distributions of both the gas temperature and the NO ground state density. A clear correlation between these quantities is found and the effects of both the gas temperature and the plasma power on NO and NO2 concentrations are discussed, revealing how the NO oxidation is already significant in the plasma afterglow region and how the gas flow rate is a crucial parameter affecting the temperature gradients. >From a technological level, the conventional approach of introducing external resistors to stabilize the arc is challenged by studying both its performance and its stability replacing the external resistor with an inductor. We conclude that similar stabilization results can be obtained while significantly lowering the overall energy cost, which decreased from up to a maximum of 7.9 MJ/mol N to 3 MJ/mol N. Finally, we study whether a small-scale fertilizer production facility based on a gliding arc plasma can be a local competitive alternative. This is done by proposing a comparative model to understand how capital, operative expenditures and transport costs affect the production costs. The model highlights how, with the current best available technology, plasma-based nitrogen fixation, while being an interesting alternative for NOx synthesis, still requires a more efficient use of H2 for direct NH3 production.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:205259 Serial 9175
Permanent link to this record
 

 
Author Brognara, A.; Kashiwar, A.; Jung, C.; Zhang, X.; Ahmadian, A.; Gauquelin, N.; Verbeeck, J.; Djemia, P.; Faurie, D.; Dehm, G.; Idrissi, H.; Best, J.P.; Ghidelli, M.
Title Tailoring mechanical properties and shear band propagation in ZrCu metallic glass nanolaminates through chemical heterogeneities and interface density Type A1 Journal article
Year 2024 Publication Small Structures Abbreviated Journal
Volume Issue Pages 2400011-11
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The design of high‐performance structural thin films consistently seeks to achieve a delicate equilibrium by balancing outstanding mechanical properties like yield strength, ductility, and substrate adhesion, which are often mutually exclusive. Metallic glasses (MGs) with their amorphous structure have superior strength, but usually poor ductility with catastrophic failure induced by shear bands (SBs) formation. Herein, we introduce an innovative approach by synthesizing MGs characterized by large and tunable mechanical properties, pioneering a nanoengineering design based on the control of nanoscale chemical/structural heterogeneities. This is realized through a simplified model Zr 24 Cu 76 /Zr 61 Cu 39 , fully amorphous nanocomposite with controlled nanoscale periodicity ( Λ , from 400 down to 5 nm), local chemistry, and glass–glass interfaces, while focusing in‐depth on the SB nucleation/propagation processes. The nanolaminates enable a fine control of the mechanical properties, and an onset of crack formation/percolation (>1.9 and 3.3%, respectively) far above the monolithic counterparts. Moreover, we show that SB propagation induces large chemical intermixing, enabling a brittle‐to‐ductile transition when Λ  ≤ 50 nm, reaching remarkably large plastic deformation of 16% in compression and yield strength ≈2 GPa. Overall, the nanoengineered control of local heterogeneities leads to ultimate and tunable mechanical properties opening up a new approach for strong and ductile materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-05-20
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2688-4062 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:205798 Serial 9176
Permanent link to this record
 

 
Author Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V.
Title Tailoring weak and metallic phases in a strong topological insulator by strain and disorder : conductance fluctuations signatures Type A1 Journal article
Year 2024 Publication Physical review B Abbreviated Journal
Volume 109 Issue 4 Pages 045129-7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Transport measurements are readily used to probe different phases in disordered topological insulators (TIs), where determining topological invariants explicitly is challenging. On that note, universal conductance fluctuations (UCF) theory asserts the conductance G for an ensemble has a Gaussian distribution, and that standard deviation 8G depends solely on the symmetries and dimensions of the system. Using a real-space tight -binding Hamiltonian on a system with Anderson disorder, we explore conductance fluctuations in a thin Bi2Se3 film and demonstrate the agreement of their behavior with UCF hypotheses. We further show that magnetic field applied out-of-plane breaks the time -reversal symmetry and transforms the system's Wigner-Dyson class from root symplectic to unitary, increasing 8G by 2. Finally, we reveal that while Bi2Se3 is a strong TI, weak TI and metallic phases can be stabilized in presence of strain and disorder, and detected by monitoring the conductance fluctuations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001173938400008 Publication Date 2024-01-16
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited 1 Open Access
Notes Approved Most recent IF: 3.7; 2024 IF: 3.836
Call Number UA @ admin @ c:irua:204765 Serial 9177
Permanent link to this record
 

 
Author Xiao, H.; Wen, H.; Xu, W.; Cheng, Y.; Zhang, J.; Cheng, X.; Xiao, Y.; Ding, L.; Li, H.; He, B.; Peeters, F.M.
Title Terahertz magneto-optical properties of Nitrogen-doped diamond Type A1 Journal article
Year 2024 Publication Infrared physics and technology Abbreviated Journal
Volume 138 Issue Pages 105237-105239
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Nitrogen-doped diamond (N-D) is one of the most important carbon-based electronic and optical materials. Here we study the terahertz (THz) magneto-optical (MO) properties of N-D grown by microwave plasma-enhanced chemical vapor deposition. The optical microscope, SEM, XRD, Raman spectrum, FTIR spectroscopy and XPS are used for the characterization of N-D samples. Applying THz time-domain spectroscopy (TDS), in combination with the polarization test and the presence of magnetic field in Faraday geometry, THz MO transmissions through N-D are measured from 0 to 8 T at 80 K. The complex right- and left-handed circular transmission coefficients and MO conductivities for N-D are obtained accordingly. Through fitting the experimental results with theoretical formulas of the dielectric constant and MO conductivities for an electron gas, we are able to determine magneto-optically the key electronic parameters of N-D, such as the static dielectric constant epsilon b, the electron density ne, the electronic relaxation time tau, the electronic localization factor alpha and, particularly, the effective electron mass m* obtained under non-resonant condition. The dependence of these parameters upon magnetic field is examined and analyzed. We find that the MO conductivities of N-D can be described rightly by the MO Drude-Smith formulas developed by us previously. It is shown that N-doping and the presence of the magnetic field can lead towards the larger epsilon b and heavier m* in diamond, while ne/tau/alpha in N-D decreases/increases/decreases with increasing magnetic field. The results obtained from this work are benefit to us in gaining an in-depth understanding of the electronic and optoelectronic properties of N-D.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001200173100001 Publication Date 2024-02-15
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1350-4495 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.3 Times cited Open Access
Notes Approved Most recent IF: 3.3; 2024 IF: 1.713
Call Number UA @ admin @ c:irua:205523 Serial 9178
Permanent link to this record
 

 
Author Hassani, N.; Movafegh-Ghadirli, A.; Mahdavifar, Z.; Peeters, F.M.; Neek-Amal, M.
Title Two new members of the covalent organic frameworks family : crystalline 2D-oxocarbon and 3D-borocarbon structures Type A1 Journal article
Year 2024 Publication Computational materials science Abbreviated Journal
Volume 241 Issue Pages 1-9
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Oxocarbons, known for over two centuries, have recently revealed a long-awaited facet: two-dimensional crystalline structures. Employing an intelligent global optimization algorithm (IGOA) alongside densityfunctional calculations, we unearthed a quasi -flat oxocarbon (C 6 0 6 ), featuring an oxygen -decorated hole, and a novel 3D-borocarbon. Comparative analyses with recently synthesized isostructures, such as 2D -porous carbon nitride (C 6 N 6 ) and 2D -porous boroxine (B 6 0 6 ), highlight the unique attributes of these compounds. All structures share a common stoichiometry of X 6 Y 6 (which we call COF-66), where X = B, C, and Y = B, N, O (with X not equal Y), exhibiting a 2D -crystalline structure, except for borocarbon C 6 B 6 , which forms a 3D crystal. In our comprehensive study, we conducted a detailed exploration of the electronic structure of X 6 Y 6 compounds, scrutinizing their thermodynamic properties and systematically evaluating phonon stability criteria. With expansive surface areas, diverse pore sizes, biocompatibility, pi-conjugation, and distinctive photoelectric properties, these structures, belonging to the covalent organic framework (COF) family, present enticing prospects for fundamental research and hold potential for biosensing applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001215960700001 Publication Date 2024-04-23
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-0256 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.3 Times cited Open Access
Notes Approved Most recent IF: 3.3; 2024 IF: 2.292
Call Number UA @ admin @ c:irua:206005 Serial 9179
Permanent link to this record
 

 
Author Li, C.; Lyu, Y.-Y.; Yue, W.-C.; Huang, P.; Li, H.; Li, T.; Wang, C.-G.; Yuan, Z.; Dong, Y.; Ma, X.; Tu, X.; Tao, T.; Dong, S.; He, L.; Jia, X.; Sun, G.; Kang, L.; Wang, H.; Peeters, F.M.; Milošević, M.V.; Wu, P.; Wang, Y.-L.
Title Unconventional superconducting diode effects via antisymmetry and antisymmetry breaking Type A1 Journal article
Year 2024 Publication Nano letters Abbreviated Journal
Volume 24 Issue 14 Pages 4108-4116
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001193010700001 Publication Date 2024-03-27
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record
Impact Factor 10.8 Times cited Open Access
Notes Approved Most recent IF: 10.8; 2024 IF: 12.712
Call Number UA @ admin @ c:irua:205553 Serial 9180
Permanent link to this record
 

 
Author Chai, Z.-N.; Wang, X.-C.; Yusupov, M.; Zhang, Y.-T.
Title Unveiling the interaction mechanisms of cold atmospheric plasma and amino acids by machine learning Type A1 Journal article
Year 2024 Publication Plasma processes and polymers Abbreviated Journal
Volume Issue Pages 1-26
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma medicine has attracted tremendous interest in a variety of medical conditions, ranging from wound healing to antimicrobial applications, even in cancer treatment, through the interactions of cold atmospheric plasma (CAP) and various biological tissues directly or indirectly. The underlying mechanisms of CAP treatment are still poorly understood although the oxidative effects of CAP with amino acids, peptides, and proteins have been explored experimentally. In this study, machine learning (ML) technology is introduced to efficiently unveil the interaction mechanisms of amino acids and reactive oxygen species (ROS) in seconds based on the data obtained from the reactive molecular dynamics (MD) simulations, which are performed to probe the interaction of five types of amino acids with various ROS on the timescale of hundreds of picoseconds but with the huge computational load of several days. The oxidative reactions typically start with H-abstraction, and the details of the breaking and formation of chemical bonds are revealed; the modification types, such as nitrosylation, hydroxylation, and carbonylation, can be observed. The dose effects of ROS are also investigated by varying the number of ROS in the simulation box, indicating agreement with the experimental observation. To overcome the limits of timescales and the size of molecular systems in reactive MD simulations, a deep neural network (DNN) with five hidden layers is constructed according to the reaction data and employed to predict the type of oxidative modification and the probability of occurrence only in seconds as the dose of ROS varies. The well-trained DNN can effectively and accurately predict the oxidative processes and productions, which greatly improves the computational efficiency by almost ten orders of magnitude compared with the reactive MD simulation. This study shows the great potential of ML technology to efficiently unveil the underpinning mechanisms in plasma medicine based on the data from reactive MD simulations or experimental measurements. In this study, since reactive molecular dynamics simulation can currently only describe interactions between a few hundred atoms in a few hundred picoseconds, deep neural networks (DNN) are introduced to enhance the simulation results by predicting more data efficiently. image
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001202061200001 Publication Date 2024-04-15
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1612-8850 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.5 Times cited Open Access
Notes Approved Most recent IF: 3.5; 2024 IF: 2.846
Call Number UA @ admin @ c:irua:205512 Serial 9181
Permanent link to this record
 

 
Author O'Modhrain, C.; Trenchev, G.; Gorbanev, Y.; Bogaerts, A.
Title Upscaling plasma-based CO₂ conversion : case study of a multi-reactor gliding arc plasmatron Type A1 Journal article
Year 2024 Publication ACS Engineering Au Abbreviated Journal
Volume Issue Pages
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Atmospheric pressure plasmas have shifted in recent years from being a burgeoning research field in the academic setting to an actively investigated technology in the chemical, oil, and environmental industries. This is largely driven by the climate change mitigation efforts, as well as the evident pathways of value creation by converting greenhouse gases (such as CO2) into useful chemical feedstock. Currently, most high technology readiness level (TRL) plasma-based technologies are based on volumetric and power-based scaling of thermal plasma systems, which results in large capital investment and regular maintenance costs. This work investigates bringing a quasi-thermal (so-called “warm”) plasma setup, namely, a gliding arc plasmatron, from a lab-scale to a pilot-scale capacity with an increase in throughput capacity by a factor of 10. The method of scaling is the parallelization of plasmatron reactors within a single housing, with the aim of maintaining a warm plasma regime while simultaneously improving build cost and efficiency (compared to separate reactors operating in parallel). Special attention is also given to the safety and control features implemented in the setup, a key component required for integration into industrial systems. The performance of the multi-reactor gliding arc plasmatron (MRGAP) reactor is investigated, focusing on the influence of flow rate and the number of active reactors. The location of active reactors was deemed to have a negligible effect on the monitored metrics of conversion, energy efficiency, and energy cost. The optimum operating conditions were found to be with the most active reactors (five) at the highest investigated flow rate (80 L/min). Analysis of results suggests that an optimum conversion (9%) and plug power-based energy efficiency (19%) can be maintained at a specific energy input (SEI) around 5.3 kJ/L (or 1 eV/molecule). The concept of parallelization of plasmatron reactors within a singular housing was demonstrated to be a viable method for scaling up from a lab-scale to a prototype-scale device, with performance analysis suggesting that increasing the power (through adding more reactor channels) and total flow rate, while maintaining an SEI around 5.3 or 4.2 kJ/L, i.e., 1.3 or 1 eV/molecule (based on plug power and plasma-deposited power, respectively), can result in increased conversion rate without sacrificing absolute conversion or energy efficiency.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001166625200001 Publication Date 2024-02-14
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:204749 Serial 9182
Permanent link to this record
 

 
Author Teleshkan, E.; Van Schoubroeck, S.; Spiller, M.; Van Passel, S.
Title Assessing policy impacts on nutrient circularity : a comprehensive review Type A1 Journal article
Year 2024 Publication Nutrient cycling in agroecosystems Abbreviated Journal
Volume Issue Pages 1-15
Keywords A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM)
Abstract Nutrient circularity is an emerging concept that seeks to address the environmental problems and nutrient losses caused by agriculture and food consumption. The implementation of circular nutrient technologies and practices (CNTPs), that recover, reuse, and recycle nutrients from agricultural and urban waste is an important policy objective. Yet, which policies govern the adoption of CNTPs is not well defined. This study presents the first systematic review of impact evaluations of policy measures that aim to improve nutrient circularity regulating components of the biological cycle of the circular economy, particularly focusing on bioaccessible nutrients. The key CNTPs that were subject to existing impact evaluations were identified. CNTPs were categorized into nutrient circularity themes, with manure management emerging as a prominent focus. The reviewed studies implemented several methods to assess the impacts of policies on various dependent variables, associated with nutrient circularity. Economic simulation models and linear programming were the most prevalent methods for impact evaluation. Policy measures were labeled as either enabling or not-enabling nutrient circularity based on whether they sufficiently promoted nutrient circularity through facilitating the adoption of CNTPs, and controlling for soil, water and air health, preventing its contamination. It is concluded that incentive policies, harmonizing market support, tax incentives, and technological advancements, as well as coherence of local, national and cross-country legislation prove indispensable in steering the economic feasibility and sustainability of CNTPs, offering a promising avenue for progress and a transformative shift towards nutrient circularity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001175764500001 Publication Date 2024-02-29
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1385-1314; 1573-0867 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.1 Times cited Open Access
Notes Approved Most recent IF: 3.1; 2024 IF: 1.843
Call Number UA @ admin @ c:irua:204250 Serial 9185
Permanent link to this record
 

 
Author Reynaert, S.; D’Hose, T.; de Boeck, H.J.; Laorden, D.; Dult, L.; Verbruggen, E.; Nijs, I.
Title Can permanent grassland soils with elevated organic carbon buffer negative effects of more persistent precipitation regimes on forage grass performance? Type A1 Journal article
Year 2024 Publication The science of the total environment Abbreviated Journal
Volume 918 Issue Pages 170623-15
Keywords A1 Journal article; Plant and Ecosystems (PLECO) – Ecology in a time of change
Abstract Agricultural practices enhancing soil organic carbon (SOC) show potential to buffer negative effects of climate change on forage grass performance. We tested this by subjecting five forage grass varieties differing in fodder quality and drought/flooding resistance to increased persistence in summer precipitation regimes (PR) across sandy and sandy-loam soils from either permanent (high SOC) or temporary grasslands (low SOC) in adjacent parcels. Over the course of two consecutive summers, monoculture mesocosms were subjected to rainy/dry weather alternation either every 3 days or every 30 days, whilst keeping total precipitation equal. Increased PR persistence induced species-specific drought damage and productivity declines. Soils from permanent grasslands with elevated SOC buffered plant quality, but buffering effects of SOC on drought damage, nutrient availability and yield differed between texture classes. In the more persistent PR, Festuca arundinacea FERMINA was the most productive species but had the lowest quality under both ample water supply and mild soil drought, whilst under the most intense soil droughts, Festulolium FESTILO maintained the highest yields. The hybrid Lolium × boucheanum kunth MELCOMBI had intermediate productivity and both Lolium perenne varieties showed the lowest yields under soil drought, but the highest forage quality (especially the tetraploid variety MELFORCE). Performance varied with plant maturity stage and across seasons/years and was driven by altered water and nutrient availability and related nitrogen nutrition among species during drought and upon rewetting. Moreover, whilst permanent grassland soils showed the most consistent positive effects on plant performance, their available water capacity also declined under increased PR persistence. We conclude that permanent grassland soils with historically elevated SOC likely buffer negative effects of increasing summer weather persistence on forage grass performance, but may also be more sensitive to degradation under climate change.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001183615800001 Publication Date 2024-02-04
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0048-9697; 1879-1026 ISBN Additional Links UA library record; WoS full record
Impact Factor 9.8 Times cited Open Access
Notes Approved Most recent IF: 9.8; 2024 IF: 4.9
Call Number UA @ admin @ c:irua:204498 Serial 9191
Permanent link to this record
 

 
Author Van Hoecke, L.
Title CFD-Assisted design of fluidized reactors for H2 release from LOHC Type Doctoral thesis
Year 2024 Publication Abbreviated Journal
Volume Issue Pages XXXIII, 181 p.
Keywords Doctoral thesis; Engineering sciences. Technology
Abstract Hydrogen (H2) is expected to become a key molecule in the transition towards a society running on renewable energy. It can be used to store excess renewable energy at peak production moments and release this energy at a later stage when renewable energy production is less. However, storing H2 is challenging due to the low density of this gas. As a solution, Liquid Organic Hydrogen Carriers or LOHC molecules have been proposed in the passed to increase volumetric energy density of H2. LOHC are a class of molecules that have storage sites available, to which the H2 gas can be chemically bounded. The LOHC molecule under investigation was dibenzyltoluene (DBT), which is an oil like liquid, that is easy to transport and poses little fire or explosion risks. To release the H2 from the DBT carrier, via a so-called dehydrogenation reaction, efficient mass and heat transfer is required during the process, since a large volume increase is expected from H2 release and the reaction is endothermic, i.e., a self – cooling process that takes place at temperatures around 300 C. The heat has to be supplied specifically to the active sites of catalyst particles that are present inside the reactor and which enable the dehydrogenation to proceed. For heat transfer limited processes fluidized bed reactors are often used, which is a type of reactor where the particle phase is being agitated by the fluid flow. The research proposed in this work, was to explore via computational fluid dynamics (CFD) simulations the possibilities and challenges of using fluidized bed reactors for the dehydrogenation of LOHC. The model selection required for CFD simulations of a three-phase system was investigated in this work, with a main emphasis on the drag model selection. The CFD modelling study was focused on the use of swirling fluidized bed reactors, since it was hypothesised that the swirling effect could also aid in increased removal of the gas phase from the reaction medium to increase the efficiency of the process. Ultimately, it was shown that the main challenges in the design of fluidized bed reactors will be to create uniform particle distribution inside the reactor. A new design for a dehydrogenation reactor is proposed based on the insights gained in this thesis.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-06-14
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:205645 Serial 9192
Permanent link to this record
 

 
Author Deleu, N.; Hillen, M.; Steenackers, G.; Borms, G.; Janssens, K.; Van der Stighelen, K.; Van der Snickt, G.
Title Combined macro X-ray fluorescence (MA-XRF) and pulse phase thermography (PPT) imaging for the technical study of panel paintings Type A1 Journal article
Year 2024 Publication Talanta : the international journal of pure and applied analytical chemistry Abbreviated Journal
Volume 270 Issue Pages 125533-11
Keywords A1 Journal article; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Museum staff usually relies on a proven combination of X-ray radiography (XRR) and infrared reflectography (IRR) to study paintings in a non-destructive manner. In the last decades, however, the research toolbox of heritage scientists has expanded considerably, with a prime example being macro X-ray fluorescence (MA-XRF), producing element-specific images. The goal of this article is to illustrate the added value of augmenting MA-XRF with pulse phase thermography (PPT), a variant of active infrared thermographic imaging (IRT), which is an innovative diagnostic method that is able to reveal variations between or in materials, based on a different response to minor fluctuations in temperature when irradiated with optical radiation. By examining three 16thand 17th-century panel paintings we assess the extent in which combined MA-XRF and PPT contributes to a better understanding of two commonly encountered interventions to panel paintings: (a) Anstuckungen (enlargement of the panel) or (b) substitutions (replacement of part of the panel). Yielding information from different depths of the painting, these two techniques proved highly complementary with IRR and XRR, expanding the understanding of the build-up, genesis, and material history of the paintings. While MA-XRF documented the interventions to the wooden substrate indirectly by revealing variations in painting materials, paint handling and/ or layer sequence between the original part and the extended or replaced planks, PPT proved beneficial for the study of the wooden support itself, by providing a clear image of the wood structure quasi-free of distortion by the superimposed paint or cradling. XRR, on the other hand, revealed other features from the wood structure, not visible with PPT, and allowed looking through the wooden panels, revealing e.g. the dowels used for joining the planks. Additionally, IRR visualised dissimilarities in the underdrawings. In this way, the results indicate that PPT has the potential to become an acknowledged add-on to the expanding set of imaging methods for paintings, especially when used in combination with MA-XRF, IRR and XRR.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001144098200001 Publication Date 2023-12-09
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0039-9140; 1873-3573 ISBN Additional Links UA library record; WoS full record
Impact Factor 6.1 Times cited Open Access
Notes Approved Most recent IF: 6.1; 2024 IF: 4.162
Call Number UA @ admin @ c:irua:203764 Serial 9193
Permanent link to this record
 

 
Author Lugli, L.F.; Fuchslueger, L.; Vallicrosa, H.; Van Langenhove, L.; Ranits, C.; Garberi, P.R.F.; Verryckt, L.; Grau, O.; Brechet, L.; Peguero, G.; Llusia, J.; Ogaya, R.; Marquez, L.; Portillo-Estrada, M.; Ramirez-Rojas, I.; Courtois, E.; Stahl, C.; Sardans, J.; Penuelas, J.; Verbruggen, E.; Janssens, I.
Title Contrasting responses of fine root biomass and traits to large-scale nitrogen and phosphorus addition in tropical forests in the Guiana shield Type A1 Journal article
Year 2024 Publication Oikos: a journal of ecology Abbreviated Journal
Volume 2024 Issue 4 Pages e10412-14
Keywords A1 Journal article; Engineering sciences. Technology; Plant and Ecosystems (PLECO) – Ecology in a time of change
Abstract Fine roots mediate plant nutrient acquisition and growth. Depending on soil nutrient availability, plants can regulate fine root biomass and morphological traits to optimise nutrient acquisition. Little is known, however, about the importance of these parameters influencing forest functioning. In this study, we measured root responses to nutrient additions to gain a mechanistic understanding of plant adaptations to nutrient limitation in two tropical forests in French Guiana, differing twofold in their soil nutrient statuses. We analysed the responses of root biomass, mean root diameter (RD), specific root length (SRL), specific root area (SRA), root tissue density (RTD) and carbon (C), nitrogen (N) and phosphorus (P) concentrations in roots down to 15 cm soil depth after three years of N and P additions. At the lower-fertility site Paracou, no changes in root biomass or morphological traits were detected with either N or P addition, although P concentrations in roots increased with P addition. In the higher fertility site, Nouragues, root biomass and P concentrations in roots increased with P addition, with no changes in morphological traits. In contrast, N addition shifted root traits from acquisitive to more conservative by increasing RTD. A significant interaction between N and P in Nouragues pointed to stronger responses to P addition in the absence of N. Our results suggest that the magnitude and direction of root biomass and trait expression were regulated by soil fertility, corroborated by the response to N or P additions. At low fertility sites, we found lower plasticity in root trait expression compared to more fertile conditions, where N and P additions caused stronger and antagonistic responses. Identifying the exact role of mechanisms affecting root nutrient uptake in Amazon forests growing in different soils will be crucial to foresee if and how rapid global changes can affect their carbon allocation.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001142552200001 Publication Date 2024-01-16
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0030-1299 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.4 Times cited Open Access
Notes Approved Most recent IF: 3.4; 2024 IF: 4.03
Call Number UA @ admin @ c:irua:202834 Serial 9195
Permanent link to this record
 

 
Author Pastorelli, G.; Miranda, A.S.O.; Avranovich Clerici, E.; d'Imporzano, P.; Hansen, B.V.; Janssens, K.; Davies, G.R.; Borring, N.
Title Darkening of lead white in old master drawings and historic prints : a multi-analytical investigation Type A1 Journal article
Year 2024 Publication Microchemical journal Abbreviated Journal
Volume 199 Issue Pages 109912-10
Keywords A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract Old master drawings and historic prints often feature white highlights, which are typically painted using lead white, one of the most widely used historical white pigments. However, it has been observed that many of these highlights discolour over time, becoming dark brown or black due to unclear degradation processes. This phenomenon not only misrepresents the original artefacts, threatening their suitability for public display, but also diminishes their longevity. To ensure their preservation, it is essential to determine why some lead white highlights in these museum objects retain their light tones while others are prone to darkening. The objective of this study was to identify the relationships between the composition, provenance, and production methods of lead white pigments, and their role in the discolouration observed on drawings, lithographs and early photographs. Selected samples and artefacts were examined using a range of analytical techniques, namely X-ray fluorescence spectroscopy (XRF), X-ray powder diffraction (XRPD), and lead isotope analysis. While XRF analyses confirmed the presence of lead as the primary element in the majority of the highlights, XRPD measurements identified a variety of lead compounds such as the carbonates cerussite and hydrocerussite alongside galena-a black crystalline sulfide-and lead sulfates. Additionally, isotope analyses classified the lead raw materials into five main groups. Through these measurements, the examined lead white pigments were categorised based on their compositional properties in relation to the raw materials used, as well as their geographical and temporal origin. A significant finding is that lead white pigments from different production periods, spanning from older to more modern, may be characterised by varying proneness to discolouration irrespective of their provenance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001166502200001 Publication Date 2024-01-03
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0026-265x; 0026-265x ISBN Additional Links UA library record; WoS full record
Impact Factor 4.8 Times cited Open Access
Notes Approved Most recent IF: 4.8; 2024 IF: 3.034
Call Number UA @ admin @ c:irua:205450 Serial 9197
Permanent link to this record
 

 
Author Lembrechts, J.; Clavel, J.; Lenoir, J.; Haider, S.; McDougall, K.; Nunez, M.; Alexander, J.; Barros, A.; Milbau, A.; Seipel, T.; Verbruggen, E.; Nijs, I.
Title Dataset: Roadside disturbance promotes plant communities with arbuscular mycorrhizal associations in mountain regions worldwide Type Dataset
Year 2024 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; Plant and Ecosystems (PLECO) – Ecology in a time of change
Abstract Aim: We aimed to assess the impact of road disturbances on the dominant mycorrhizal types in ecosystems at the global level and how this mechanism can potentially lead to lasting plant community changes. Location: Globally distributed mountain regions Time Period: 2007-2018 Taxa studied: Plants (linked to their associated mycorrhizal fungi) Methods: We used a database of coordinated plant community surveys following mountain roads from 894 plots in 11 mountain regions across the globe in combination with an existing database of mycorrhizal-plant associations in order to approximate the relative abundance of mycorrhizal types in natural and disturbed environments. Results: Our findings show that roadside disturbance promotes the cover of plants associated with arbuscular mycorrhizal (AM) fungi. This effect is especially strong in colder mountain environments and in mountain regions where plant communities are dominated by ectomycorrhizal (EcM) or ericoid-mycorrhizal (ErM) associations. Furthermore, non-native plant species, which we confirmed to be mostly AM plants, are more successful in environments dominated by AM associations. Main Conclusions: These biogeographical patterns suggest that changes in mycorrhizal types could be a crucial factor in the worldwide impact of anthropogenic disturbances on mountain ecosystems. Indeed, roadsides foster AM-dominated systems, where AM-fungi might aid AM-associated plant species while potentially reducing the biotic resistance against invasive non-native species, often also associated with AM networks. Restoration efforts in mountain ecosystems will have to contend with changes in the fundamental make-up of EcM- and ErM plant communities induced by roadside disturbance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:206132 Serial 9198
Permanent link to this record
 

 
Author Larraín, M.; Billen, P.; Cifuentes, L.; Van Passel, S.
Title Economic and environmental implications of policy instruments for the circular economy : a case study for postconsumer polyethylene film recycling in Europe Type A1 Journal article
Year 2024 Publication Resources, conservation and recycling Abbreviated Journal
Volume 204 Issue Pages 107519-11
Keywords A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS)
Abstract The objective of this paper is to examine the recycling rates for mechanical and thermochemical recycling of postconsumer polyethylene flexible packaging after the implementation of different policy instruments. The study uses a supply chain equilibrium model that incorporates market data and techno-economic assessments to simulate market equilibrium. It combines this with a life cycle assessment to explore the environmental implications of implementing different policy instruments. The results show that instruments that do not target a specific technology are more likely to increase thermochemical recycling than mechanical recycling. Furthermore, a higher recycling rate is not equivalent to a better environmental outcome. An increased collection target that ensures a supply of plastic waste would increase the overall recycling rates the most. A recycled content standard for mechanical recycling would lead to the highest increase in mechanical recycling, with top results for environmental indicators, but low results for economic indicators.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-02-29
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-3449 ISBN Additional Links UA library record
Impact Factor 13.2 Times cited Open Access
Notes Approved Most recent IF: 13.2; 2024 IF: 3.313
Call Number UA @ admin @ c:irua:203485 Serial 9202
Permanent link to this record
 

 
Author Gebremariam, Y.A.; Dessein, J.; Wondimagegnhu, B.A.; Breusers, M.; Lenaerts, L.; Adgo, E.; Van Passel, S.; Minale, A.S.; Frankl, A.
Title Listen to the radio and go on field trips : a study on farmers' attributes to opt for extension methods in Northwest Ethiopia Type A1 Journal article
Year 2024 Publication AIMS Agriculture and Food Abbreviated Journal
Volume 9 Issue 1 Pages 3-29
Keywords A1 Journal article; Pharmacology. Therapy; Engineering Management (ENM)
Abstract Extension professionals are expected to help disseminate agricultural technologies, information, knowledge and skills to farmers. In order to develop valuable and long-lasting extension services, it is essential to understand the methods of extension that farmers find most beneficial. This understanding helps adopt improved practices, overcome barriers, provide targeted interventions and continuously improve agricultural extension programs. Thus, assessing factors affecting farmers' choice of agricultural extension methods is essential for developing extension methods that comply with farmers' needs and socio-economic conditions. Therefore, we analyzed the factors affecting farmers' preferences in extension methods, using cross-sectional data collected from 300 households in two sample districts and 16 Kebelles in Ethiopia between September 2019 and March 2020. Four extension methods, including training, demonstration, office visits and phone calls were considered as outcome variables. We fitted a multivariate probit model to estimate the factors that influence farmers' choice of extension methods. The results of the study showed that the number of dependents in the household head, formal education and membership of Idir (an informal insurance program a community or group runs to meet emergencies) were negatively associated with farmers' choices to participate in different extension methods compared to no extension. On the other hand, the sex of the household head, farm experience, participation in non-farm activities, monetary loan access, owning a mobile phone, radio access and membership of cooperatives were found to have a statistically significant positive impact on farmers' choices of extension methods. Based on these findings, the government and the concerned stakeholders should take farmers' socio-economic and institutional traits into account when selecting and commissioning agricultural extension methods. This could help to develop contextually relevant extension strategies that are more likely to be chosen and appreciated by farmers. Furthermore, such strategies can aid policymakers in designing extension programs that cater to farmers' needs and concerns. In conclusion, farmers' socio-economic and institutional affiliation should be taken into consideration when selecting agricultural extension methods.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001124466300001 Publication Date 2023-12-13
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2471-2086 ISBN Additional Links UA library record; WoS full record
Impact Factor 1.8 Times cited Open Access
Notes Approved Most recent IF: 1.8; 2024 IF: NA
Call Number UA @ admin @ c:irua:202154 Serial 9209
Permanent link to this record
 

 
Author Finizola e Silva, M.; Van Schoubroeck, S.; Cools, J.; Aboge, D.O.; Ouma, M.; Olweny, C.; Van Passel, S.
Title Local actors' perspectives on sustainable food value chains : evidence from a Q-methodology study in Kenya Type Administrative Services
Year 2024 Publication Journal of Environmental Studies and Sciences Abbreviated Journal
Volume 14 Issue 1 Pages 36-51
Keywords Administrative Services; A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM)
Abstract Governments and international organizations are increasingly determined to create more sustainable food value chains (SFVCs). However, only little empirical evidence is available on how SFVCs are understood. Enquiring African food value chain actors allows gathering valuable insights into their perception of sustainability, which characteristics of sustainable food value chains they prioritize, and which obstacles to a sustainable transformation they identify. By means of a Q-methodology involving interviews with 33 Kenyan respondents, four perspectives were distinguished. The first perspective, “economic productivity and growth,” prioritizes economic growth and has only limited attention to the social dimension of sustainability. The second perspective, “food security and food availability,” believes that ensuring food security should be the key goal of SFVCs. The third perspective, “environment first,” is dedicated to the environmental dimension of sustainability; the perspective implies that protecting natural resources is the primary way to sustain this level of production. The fourth perspective, “transformative knowledge,” entails that by innovating and sharing knowledge, food value chains can become more sustainable in different areas. Overall, this study provides reliable insights into how Kenyan food value chain actors perceive sustainability in their sector and which elements they believe should be prioritized when rethinking food systems. The study results are valuable for policy-making to further define an SFVC in Kenya and to pave the way for a sustainable transformation of the food sector in developing countries.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001063371200001 Publication Date 2023-09-11
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2190-6483 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:199200 Serial 9210
Permanent link to this record
 

 
Author De Keyzer, M.; Soens, T.; Verbruggen, C.
Title Mens en natuur : een geschiedenis Type MA2 Book as author
Year 2024 Publication Abbreviated Journal
Volume Issue Pages 313 p.
Keywords MA2 Book as author; History; Centre for Urban History
Abstract Onze relatie met de natuur om ons heen is, op zijn zachtst gezegd, ingewikkeld. Mensen gingen niet plots een bedreiging vormen voor het leven op aarde nadat ze er eeuwenlang mee in harmonie hadden geleefd. Verschillende ideeën over de omgang met de natuurlijke omgeving – sommige duurzaam, andere ronduit desastreus – hebben altijd naast elkaar bestaan. We waren er ons al verrassend vroeg van bewust dat ons handelen een nefaste impact kon hebben op de natuur. Maar die bezwaren werden geregeld aan de kant geschoven. Deze inleiding tot de milieugeschiedenis helpt de lezer te begrijpen hoe onze hedendaagse problematische omgang met de natuur en ons milieu tot stand is gekomen. Het is een introductie tot het recente onderzoek naar de relatie tussen mens en natuur doorheen de eeuwen, in de Lage Landen en ver daarbuiten.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN 978-94-014-0395-5 Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:205213 Serial 9212
Permanent link to this record
 

 
Author Smets, B.; Boschker, H.T.S.; Wetherington, M.T.; Lelong, G.; Hidalgo-Martinez, S.; Polerecky, L.; Nuyts, G.; De Wael, K.; Meysman, F.J.R.
Title Multi-wavelength Raman microscopy of nickel-based electron transport in cable bacteria Type A1 Journal article
Year 2024 Publication Frontiers in microbiology Abbreviated Journal
Volume 15 Issue Pages 1208033-16
Keywords A1 Journal article
Abstract Cable bacteria embed a network of conductive protein fibers in their cell envelope that efficiently guides electron transport over distances spanning up to several centimeters. This form of long-distance electron transport is unique in biology and is mediated by a metalloprotein with a sulfur-coordinated nickel (Ni) cofactor. However, the molecular structure of this cofactor remains presently unknown. Here, we applied multi-wavelength Raman microscopy to identify cell compounds linked to the unique cable bacterium physiology, combined with stable isotope labeling, and orientation-dependent and ultralow-frequency Raman microscopy to gain insight into the structure and organization of this novel Ni-cofactor. Raman spectra of native cable bacterium filaments reveal vibrational modes originating from cytochromes, polyphosphate granules, proteins, as well as the Ni-cofactor. After selective extraction of the conductive fiber network from the cell envelope, the Raman spectrum becomes simpler, and primarily retains vibrational modes associated with the Ni-cofactor. These Ni-cofactor modes exhibit intense Raman scattering as well as a strong orientation-dependent response. The signal intensity is particularly elevated when the polarization of incident laser light is parallel to the direction of the conductive fibers. This orientation dependence allows to selectively identify the modes that are associated with the Ni-cofactor. We identified 13 such modes, some of which display strong Raman signals across the entire range of applied wavelengths (405–1,064 nm). Assignment of vibrational modes, supported by stable isotope labeling, suggest that the structure of the Ni-cofactor shares a resemblance with that of nickel bis(1,2-dithiolene) complexes. Overall, our results indicate that cable bacteria have evolved a unique cofactor structure that does not resemble any of the known Ni-cofactors in biology.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001189511900001 Publication Date 2024-03-08
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1664-302x ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:205115 Serial 9214
Permanent link to this record
 

 
Author Pankratov, D.; Hidalgo Martinez, S.; Karman, C.; Gerzhik, A.; Gomila, G.; Trashin, S.; Boschker, H.T.S.; Geelhoed, J.S.; Mayer, D.; De Wael, K.; Meysman, F.J.R.
Title The organo-metal-like nature of long-range conduction in cable bacteria Type A1 Journal article
Year 2024 Publication Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry Abbreviated Journal
Volume 157 Issue Pages 108675-10
Keywords A1 Journal article
Abstract Cable bacteria are filamentous, multicellular microorganisms that display an exceptional form of biological electron transport across centimeter-scale distances. Currents are guided through a network of nickel-containing protein fibers within the cell envelope. Still, the mechanism of long-range conduction remains unresolved. Here, we characterize the conductance of the fiber network under dry and wet, physiologically relevant, conditions. Our data reveal that the fiber conductivity is high (median value: 27 S cm−1; range: 2 to 564 S cm−1), does not show any redox signature, has a low thermal activation energy (Ea = 69 ± 23 meV), and is not affected by humidity or the presence of ions. These features set the nickel-based conduction mechanism in cable bacteria apart from other known forms of biological electron transport. As such, conduction resembles that of an organic semi-metal with a high charge carrier density. Our observation that biochemistry can synthesize an organo-metal-like structure opens the way for novel bio-based electronic technologies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-02-25
Series Editor (up) Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1567-5394 ISBN Additional Links UA library record
Impact Factor 5 Times cited Open Access
Notes Approved Most recent IF: 5; 2024 IF: 3.346
Call Number UA @ admin @ c:irua:205117 Serial 9215
Permanent link to this record