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Author de Paula Miranda, L. url  openurl
  Title Electronic transport in two dimensional systems with defects Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume Issue Pages 104 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract (down) The pursuit for the next generation of nanodevices made scientists focus the attention to two dimensional materials. Experimental works of two dimensional materials are hardly free of structural defects, which, in turn, modify drastically the physical properties of its defect-free counterpart. In this work the presence of structural defects is study in two different materials. First, the dependence of the Hall, bend and longitudinal resistances to a perpendicular magnetic field and to vacancy defects in a four-terminal phosphorene single layer Hall bar is investigated. A tight-binding model in combination with the Landauer-Büttiker formalism is used to calculate the energy spectrum, the lead-to-lead transmissions, and the Hall and bend resistances of the system. It is shown that the terminals with zigzag edge orientation are responsible for the absence of quantized plateaus in the Hall resistance and peaks in the longitudinal resistance. A negative bend resistance in the ballistic regime is found due to the presence of high- and low- energy transport modes in the armchair and zigzag terminals, respectively. The system density of states, with single vacancy defects, shows that the presence of in-gap states is proportional to the number of vacancies. Quantized plateaus in the Hall resistance are only formed in a sufficiently clean system. The effects of different kinds of vacancies in the regime where the quantized plateaus are destroyed and a diffusive regime appears in the bend resistance are investigated. Next, we explore effects due to point defect clustering on the electronic and transport properties of bilayer graphene nanoribbons, for AA and AB stacking and zigzag and armchair boundaries, by means of the tight-binding approach and scattering matrix formalism. Evidence of vacancy concentration signatures exhibiting a maximum amplitude and an universality regardless of the system size, stacking and boundary types, in the density of states around the zero-energy level are observed. Our results are explained via the coalescence analysis of the strong sizeable vacancy clustering effect in the system and the breaking of inversion symmetry at high vacancy densities, demonstrating a similar density of states for two equivalent degrees of concentration disorder, below and above the maximum value.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:191340 Serial 7151  
Permanent link to this record
 

 
Author Godoi, R.H.M.; Avigo, D.; Campos, V.D.; Tavares, T.M.; de Marchi, M.R.R.; Van Grieken, R.; Godoi, A.F.L. doi  openurl
  Title Indoor air quality assessment of elementary schools in Curitiba, Brazil Type A3 Journal article
  Year 2009 Publication Water, air, and soil pollution : focus Abbreviated Journal  
  Volume 9 Issue 3/4 Pages 171-177  
  Keywords A3 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The promotion of good indoor air quality in schools is of particular public concern for two main reasons: (1) school-age children spend at least 30% of their time inside classrooms and (2) indoor air quality in urban areas is substantially influenced by the outdoor pollutants, exposing tenants to potentially toxic substances. Two schools in Curitiba, Brazil, were selected to characterize the gaseous compounds indoor and outdoor of the classrooms. The concentrations of benzene, toluene, ethylbenzene, and the isomers xylenes (BTEX); NO2; SO2; O3; acetic acid (HAc); and formic acid (HFor) were assessed using passive diffusion tubes. BTEX were analyzed by gas chromatographyion trap mass spectrometry and other collected gasses by ion chromatography. The concentration of NO2 varied between 9.5 and 23 µg m−3, whereas SO2 showed an interval from 0.1 to 4.8 µg m−3. Within the schools, BTEX concentrations were predominant. Formic and acetic acids inside the classrooms revealed intermediate concentrations of 1.5 µg m−3 and 1.2 µg m−3, respectively.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2009-09-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1567-7230 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:80494 Serial 8081  
Permanent link to this record
 

 
Author Vandewalle, L.A.; Gonzalez-Quiroga, A.; Perreault, P.; Van Geem, K.M.; Marin, G.B. pdf  doi
openurl 
  Title Process intensification in a gas–solid vortex unit : computational fluid dynamics model based analysis and design Type A1 Journal article
  Year 2019 Publication Industrial and engineering chemistry research Abbreviated Journal  
  Volume 58 Issue 28 Pages 12751-12765  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (down) The process intensification abilities of gas–solid vortex units (GSVU) are very promising for gas–solid processes. By working in a centrifugal force field, much higher gas–solid slip velocities can be obtained compared to gravitational fluidized beds, resulting in a significant increase in heat and mass transfer rates. In this work, local azimuthal and radial particle velocities for an experimental GSVU are simulated using the Euler–Euler framework in OpenFOAM and compared with particle image velocimetry measurements. With the validated model, the effect of the particle diameter, number of inlet slots and reactor length on the bed hydrodynamics is assessed. Starting from 1g-Geldart-B type particles, increasing the particle diameter or density, increasing the number of inlet slots or increasing the gas injection velocity leads to an increased bed stability and uniformity. However, a trade-off has to be made since increased bed stability and uniformity lead to higher shear stresses and attrition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000476686000027 Publication Date 2019-06-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0888-5885; 1520-5045 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:162122 Serial 8416  
Permanent link to this record
 

 
Author Lin, S.; Shao, L.; Hui, C.; Song, Y.; Reddy, G.V.P.; Gielis, J.; Li, F.; Ding, Y.; Wei, Q.; Shi, P.; Reddy, G.V.P. url  doi
openurl 
  Title Why does not the leaf weight-area allometry of bamboos follow the 3/2-power law? Type A1 Journal article
  Year 2018 Publication Frontiers in plant science Abbreviated Journal  
  Volume 9 Issue Pages 583  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (down) The principle of similarity (Thompson, 1917) states that the weight of an organism follows the 3/2-power law of its surface area and is proportional to its volume on the condition that the density is constant. However, the allometric relationship between leaf weight and leaf area has been reported to greatly deviate from the 3/2-power law, with the irregularity of leaf density largely ignored for explaining this deviation. Here, we choose 11 bamboo species to explore the allometric relationships among leaf area (A), density (ρ), length (L), thickness (T), and weight (W). Because the edge of a bamboo leaf follows a simplified two-parameter Gielis equation, we could show that A ∝ L2 and that A ∝ T2. This then allowed us to derive the density-thickness allometry ρ ∝ Tb and the weight-area allometry W ∝ A(b+3)/2 ≈ A9/8, where b approximates −3/4. Leaf density is strikingly negatively associated with leaf thickness, and it is this inverse relationship that results in the weight-area allometry to deviate from the 3/2-power law. In conclusion, although plants are prone to invest less dry mass and thus produce thinner leaves when the leaf area is sufficient for photosynthesis, such leaf thinning needs to be accompanied with elevated density to ensure structural stability. The findings provide the insights on the evolutionary clue about the biomass investment and output of photosynthetic organs of plants. Because of the importance of leaves, plants could have enhanced the ratio of dry material per unit area of leaf in order to increase the efficiency of photosynthesis, relative the other parts of plants. Although the conclusion is drawn only based on 11 bamboo species, it should also be applicable to the other plants, especially considering previous works on the exponent of the weight-area relationship being less than 3/2 in plants.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000431415100001 Publication Date 2018-05-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1664-462x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:150948 Serial 8758  
Permanent link to this record
 

 
Author Delabie, L.; Honoré, M.; Lenaerts, S.; Huyberechts, G.; Roggen, J.; Maes, G. doi  openurl
  Title The effect of sintering and Pd-doping on the conversion of CO to CO2 on SnO2 gas sensor materials Type A1 Journal article
  Year 1997 Publication Sensors And Actuators B-Chemical Abbreviated Journal Sensor Actuat B-Chem  
  Volume 44 Issue Pages 446-451  
  Keywords A1 Journal article  
  Abstract (down) The principal aim of this work is to study the effect of the processes of sintering and Pd doping of SnO2 gas sensor materials on the conversion of CO to CO2. For this purpose, the gas phase above screen printed sensor material is investigated using FTIR spectroscopy, while surface area, porosity and particle size measurements are performed on the SnO2 powders. During sintering, larger agglomerates of primary particles are formed, which results in a larger conversion degree of CO. The effect of Pd doping of the tin dioxide film on the CO conversion is more pronounced. The transformation of CO starts at a lower temperature and the conversion degree increases remarkably.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000071717900035 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0925-4005 ISBN Additional Links UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles  
  Impact Factor 5.401 Times cited Open Access  
  Notes Approved Most recent IF: 5.401; 1997 IF: 0.858  
  Call Number UA @ admin @ c:irua:82017 Serial 5947  
Permanent link to this record
 

 
Author Van Vlierberghe, S. pdf  doi
openurl 
  Title Crosslinking strategies for porous gelatin scaffolds Type A1 Journal article
  Year 2016 Publication Journal of materials science Abbreviated Journal  
  Volume 51 Issue 9 Pages 4349-4357  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The present work reports on the application and the evaluation of a multitude of crosslinking approaches including high-energy irradiation, redox-initiating systems and conventional carbodiimide-coupling chemistry for frozen and/or freeze-dried porous gelatin scaffolds. The latter is particularly relevant for a plethora of biomedical applications such as tissue engineering supports, wound dressings, adhesive and absorbent pads for surgery, etc. Moreover, the results obtained for gelatin can be considered a proof-of-concept to be extrapolated to other polymer systems containing double bonds and/or amines and carboxylic acids to also realize scaffold crosslinking in dry or frozen state. The results showed that high-energy irradiation at -5 A degrees C enabled sufficient segmental mobility to induce chemical crosslinking after performing a cryogenic treatment of methacrylamide-modified gelatin scaffolds. Alternatively, although several redox-initiating systems were unable to chemically crosslink functionalized gelatin, the combination of ammonium persulphate and TEMED resulted in the formation of scaffolds with a reasonable gel fraction. Interestingly, carbodiimide-coupling was found suitable to crosslink freeze-dried gelatin matrices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000370342100016 Publication Date 2016-01-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-2461 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:132277 Serial 7742  
Permanent link to this record
 

 
Author Saha, S.; Badhe, N.; Seuntjens, D.; Vlaeminck, S.E.; Biswas, R.; Nandy, T. doi  openurl
  Title Effective carbon and nutrient treatment solutions for mixed domestic-industrial wastewater in India Type A1 Journal article
  Year 2015 Publication Water science and technology Abbreviated Journal  
  Volume 72 Issue 4 Pages 651-657  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (down) The present study evaluates effectiveness of up-flow anaerobic sludge blanket (UASB) reactor followed by two post-anaerobic treatment options, namely free-surface, up-flow constructed wetland (FUP-CW) and oxygen-limited anaerobic nitrification/denitrification (OLAND) processes in treating sewage from the peri-urban areas in India receiving illegal industrial infiltrations. The UASB studies yielded robust results towards fluctuating strength of sewage and consistently removed 87-98% chemical oxygen demand (COD) at a hydraulic retention time of 1.5-2 d. The FUP-CW removed 68.5 +/- 13% COD, 68 +/- 3% NH4+-N, 38 +/- 5% PO43--P, 97.6 +/- 5% suspended particles and 97 +/- 13% fecal coliforms. Nutrient removal was found to be limiting in FUP-CW, especially in winter. Nitrogen removal in the OLAND process were 100 times higher than the FUP-CW process. Results show that UASB followed by FUP-CW can be an excellent, decentralized sewage treatment option, except during winter when nutrient removal is limited in FUP-CW. Hence, the study proposes bio-augmentation of FUP-CW with OLAND biomass for overall improvement in the performance of UASB followed by FUP-CW process.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000359387200019 Publication Date 2015-08-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0273-1223; 1996-9732 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:127775 Serial 7840  
Permanent link to this record
 

 
Author Sakarika, M.; Kornaros, M. pdf  url
doi  openurl
  Title Kinetics of growth and lipids accumulation in Chlorella vulgaris during batch heterotrophic cultivation : effect of different nutrient limitation strategies Type A1 Journal article
  Year 2017 Publication Bioresource technology Abbreviated Journal  
  Volume 243 Issue Pages 356-365  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (down) The present study aimed at: (1) determining the effect of sulfur addition on biomass growth and (2) assessing the effect of sulfur, phosphorus and nitrogen limitation on lipid accumulation by C. vulgaris SAG 211-11b. The sulfur cellular content was more than two-fold higher under nitrogen and phosphorus limitation (0.52% and 0.54% w w(-1), respectively) compared to sulfur requirements (0.20% w w(-1)) under sulfur limiting conditions. The nitrogen needs are significantly lower (2.81-3.35% w w(-1)) when compared to other microalgae and become 23% lower under nitrogen or phosphorus limitation. The microalga exhibited substrate inhibition above 30 g L-1 initial glucose concentration. Sulfur limitation had the most significant effect on lipid accumulation, resulting in maximum total lipid content of 53.43 +/- 3.93% g g(DW)(1). In addition to enhancing lipid productivity, adopting the optimal nutrient limitation strategy can result in cost savings by avoiding unnecessary nutrient additions and eliminate the environmental burden due to wasted resources. (C) 2017 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000411239300042 Publication Date 2017-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0960-8524 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:146663 Serial 8139  
Permanent link to this record
 

 
Author Sóti, V. url  openurl
  Title Catalytic detoxification of lignocellulose hydrolyzate Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages XXVII, 243 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Biochemical Wastewater Valorization & Engineering (BioWaVE)  
  Abstract (down) The present PhD research investigated the possibility of catalytic detoxification of poplar wood based and steam exploded lignocellulosic hydrolyzate with different types of laccase enzymes, with special focus on ethanol and lactic acid products at industrially relevant parameters: high final product concentration, high initial substrate loading and integrated processes. The simultaneous saccharification and fermentation (SSF) process was taken as a base case and five types of laccases were thoroughly investigated on their utilization potential. Phenolic removal from the liquid xylose rich fraction (XRF) was higher with fungal laccases (65-90 %) compared to approximately 30 % removal with bacterial laccase. Moreover, the optimal pH of fungal laccases was close to pH 4.5, the optimum for cellulase, while the bacterial laccase worked at basic pH. Integrating laccase treatment and hydrolysis together showed that fungal laccases have negative impact on final sugar concentration, while bacterial laccase had a strong positive effect. Although bacterial laccase removed less phenol and although its optimal conditions are difficult to integrate with hydrolysis, its enhancing effect on cellulase activity makes it a better candidate for application. The presence of the solid fraction (SF) alters the phenolic concentration evolution significantly, thus screening experiments with the liquid fraction alone do not provide sufficient information for the combined process. Magnetic Cross-Linked Enzyme Aggregates (m-CLEAs) immobilization was assessed for bacterial laccase. m-CLEAs decreased phenolic concentration faster at every pH compared to free bacterial laccase; however, the removal was caused by adsorption rather than by enzyme activity. Although the size of m-CLEAs particles are in the µm range, around 90 % of the initial catalyst mass was recycled from a dense (15 % substrate loading) mixture via magnetic separation. The high recycling rate is promising; m-CLEAs immobilization method can have industrial utilization potential. Minimum sugar revenue (MSR) estimations show that currently hardwood based MSR is 70 % more expensive than corn grain based MSR. About 7-10 fold cellulase activity increase will be needed until MSR will be competitive with corn grain MSR. However, m-CLEAs cellulase can already be competitive if the corn prices are in the higher regime of last year’s prices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:180125 Serial 7584  
Permanent link to this record
 

 
Author Harlay, J.; Borges, A.V.; van der Zee, C.; Delille, B.; Godoi, R.H.M.; Schiettecatte, L.-S.; Roevros, N.; Aerts, K.; Lapernat, P.-E.; Rebreanu, L.; Groom, S.; Daro, M.-H.; Van Grieken, R.; Chou, L. doi  openurl
  Title Biogeochemical study of a coccolithophore bloom in the northern Bay of Biscay (NE Atlantic Ocean) in June 2004 Type A1 Journal article
  Year 2010 Publication Progress in oceanography Abbreviated Journal  
  Volume 86 Issue 3/4 Pages 317-336  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The present paper synthesizes data obtained during a multidisciplinary cruise carried out in June 2004 at the continental margin of the northern Bay of Biscay. The data-set allows to describe the different stages of a coccolithophore bloom dominated by Emiliania huxleyi. The cruise was carried out after the main spring phytoplankton bloom that started in mid-April and peaked in mid-May. Consequently, low phosphate (PO4 < 0.2 μM) and silicate (DSi < 2.0 μM) concentrations, low partial pressure of carbon dioxide (pCO2) and high calcite saturation degree in surface waters combined with thermal stratification, probably favoured the blooming of coccolithophores. During the period of the year our cruise was carried out, internal tides induce enhanced vertical mixing at the continental shelf break leading to the injection of inorganic nutrients to surface waters that probably trigger the bloom. The bloom developed as the water-column stratified and as the water mass was advected over the continental shelf, following the general residual circulation in the area. The most developed phase of the bloom was sampled in a remote sensed high reflectance (HR) patch over the continental shelf that was characterized by low chlorophyll-a (Chl-a) concentration in surface waters (<1.0 μg L−1), high particulate inorganic carbon (PIC) concentration (not, vert, similar8 μmol L−1) and coccolithophore abundance up to 57 × 106 cells L−1. Transparent exopolymer particles (TEP) concentrations ranged between 15 and 75 μg C L−1 and carbon content of TEP represented up to 26% of the particulate organic carbon (POC; maximum concentration of 15.5 μmol L−1 in the upper 40 m). Integrated primary production (PP) ranged between 210 and 680 mg C m−2 d−1 and integrated calcification (CAL) ranged between 14 and 140 mg C m−2 d−1, within the range of PP and CAL values previously reported during coccolithophore blooms in open and shelf waters of the North Atlantic Ocean. Bacterial protein production (BPP) measurements in surface waters (0.30.7 μg C L−1 h−1) were much higher than those reported during early phases of coccolithophore blooms in natural conditions, but similar to those during peak and declining coocolithophorid blooms reported in mesocosms. Total alkalinity anomalies with respect to conservative mixing (ΔTA) down to −49 μmol kg−1 are consistent with the occurrence of biogenic precipitation of calcite, while pCO2 remained 15107 μatm lower than atmospheric equilibrium (372 μatm). The correlation between ΔTA and pCO2 suggested that pCO2 increased in part due to calcification, but this increase was insufficient to overcome the background under-saturation of CO2. This is related to the biogeochemical history of the water masses due to net carbon fixation by the successive phytoplankton blooms in the area prior to the cruise, hence, the investigated area remained a sink for atmospheric CO2 despite calcification.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000281937800001 Publication Date 2010-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0079-6611 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:84236 Serial 7560  
Permanent link to this record
 

 
Author Van Grieken, R.; Speecke, A.; Hoste, J. pdf  doi
openurl 
  Title On the precision of oxygen determinations in steel by 14-MeVv neutron activation Type A1 Journal article
  Year 1970 Publication Analytica chimica acta Abbreviated Journal  
  Volume 52 Issue 2 Pages 275-280  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The precision of the 14-MeV neutron activation determination of oxygen in steel has been examined as a function of the oxygen content for a large number of steel and cast iron samples. The experimental and the statistically expected standard deviations have been compared. In the conditions used, 2.5 counts from 16N were registered for each p.p.m. of oxygen in the samples. The neutron flux was monitored by a simultaneously irradiated oxygen standard.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116362 Serial 8332  
Permanent link to this record
 

 
Author Maciel de Menezes, R. url  openurl
  Title Skyrmionics and magnonics in chiral ferromagnets : from micromagnetic to atomistic control Type Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 222 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract (down) The precise control of skyrmionics and magnonics in magnetic materials is key to the development of novel spin-based technology and information transport applications. Essentially, the inherent stability of magnetic skyrmions (provided by their topological charge) together with their extremely small size (down to a few nanometers) and the ultralow threshold current necessary to move them in nanostructures are the main advantages of skyrmionics. Not least, magnonics offers lower power consumption compared to electronics and the excitation of high frequency (sub-100~nm wavelength) magnons makes it possible for the creation of nanometric devices for ultrafast information transport. Even though extensive research has been carried out in recent years, the precise manipulation of skyrmions and spin waves (magnons) in nanostructures is not fully mastered and needs to be addressed before making functional skyrmionic and magnonic devices. In this thesis, we reveal multiple alternatives for the manipulation of skyrmions and spin-waves in different materials, such as bulk chiral magnets, heterochiral structures, magnet-supperconductor hybrids and two-dimentional magnetic materials. We make use of a multiscale model to numerically simulate the magnetic states at each considered material, from micromagnetic to atomistic control. We first explore the different nucleation mechanisms, activation energy, and the time evolution of the skyrmion formation in chiral magnetic films, crucial for the realization of skyrmion-based devices. We show that the skyrmion lattice is formed from the conical phase progressively, most probably by the formation of chiral bobbres, followed by the cylindrical growth of individual skyrmions from the film surface. That reflects a rod-like (one-dimensional) nucleation of the skyrmion phase, with an activation barrier of several electronvolts per skyrmion for the case of MnSi (Manganese monosilicide). In addition, we reveal the interesting blinking (creation-annihilation) behavior of skyrmions close to the phase boundary between the conical and skyrmion phases, where we recall that such switching between topologically distinct states has been proposed as a bit operation for information storage. Next, we discuss the motion of ferromagnetic and antiferromagnetic skyrmions in heterochiral magnets. We report the characteristic deflection of ferromagnetic skyrmions when moving across a heterochiral interface, where the extent of such deflection is tuned by the applied spin-polarized current and the magnitude of Dzyaloshinskii-Moriya interaction. Following, we show that the antiferromagnetic skyrmion achieves much higher velocities than its ferromagnetic counterpart, yet experiences far stronger confinement in nanoengineered heterochiral tracks, which reinforces antiferromagnetic skyrmions as a favorable choice for skyrmion-based devices. After that, we study the interesting coupling of magnetic skyrmions and superconducting vortices in magnet-superconductor heterostructures. We perform numerical simulations, based on experimental observations, to demonstrate that the stray field of magnetic skyrmions can nucleate antivortices in an adjacent superconducting film, giving rise to a hybrid topological object, the skyrmion-vortex pair, which harbor promising features for skyrmionics and quantum computing applications. We then explore the manipulation of a single skyrmion-vortex pair when currents are applied into both superconducting and magnetic parts of the heterostructure, which is of importance for the facilitated skyrmion guidance in racetrack applications. Afterwards, we make use of the high tunability of magnetic parameters in two-dimensional magnetic materials to reveal the rich phase diagram of exotic magnetic configurations in magnetic monolayers with suppressed nearest-neighbour exchange, where we show that several unique cycloidal, checkerboard, row-wise and spin-ice states are stabilized by the competition between the second-nearest-neighbor exchange, Dzyaloshinskii-Moriya, and dipolar interactions. Additionally, we show the coexistence of ferromagnetic and antiferromagnetic spin-cycloids, as well as novel types of skyrmions and chiral domain walls. Finally, in the last part of the thesis, we present the spin wave properties in the two-dimensional magnetic materials CrBr$3$ and CrI$3$. Using spin-dynamics simulations parametrized from first principles, we reveal that the spin wave dispersion in such materials can be tuned in a broad range of frequencies by strain-engineering, and that a designed pattern of strain, as well as structural defects (halide vacancies) can be turned useful in the design of spin-wave guides. Lastly, we discuss the realization of magnonic crystals by moiré-periodic modulation of magnetic parameters in van der Waals heterostructures, where we show that the several nanometer small periodicities in such samples are ideal for the interference of terahertz spin waves. Recalling the wide range of possibilities for manipulating spin waves in such two-dimensional materials, we therefore suggest these systems as a front-runner for prospective terahertz magnonic applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:184244 Serial 7019  
Permanent link to this record
 

 
Author Verbueken, A.H.; van de Vijver, F.L.; Visser, W.J.; Roels, F.; Van Grieken, R.; de Broe, M.E. doi  openurl
  Title Use of laser microprobe mass analysis (LAMMA) for localizing multiple elements in soft and hard tissues Type A1 Journal article
  Year 1987 Publication Biological trace element research Abbreviated Journal  
  Volume 13 Issue Pages 397-416  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract (down) The potential of laser microprobe mass analysis (LAMMA) as a sensitive microanalytical technique was explored in applications relevant to nephrology. Aluminum and associated elements, such as iron, were localized in fresh tissue biopsies obtained from uremic patients treatment by chronic hemodialysis. The LAMMA was applied to serum, liver, bone, and parathyroid glands of such patients. In addition, we used LAMMA to evaluate the specificity and sensitivity of routine histochemistry, in particular on human bone sections stained by the aluminon method. The high, multielemental sensitivity and molecular microprobe potential of LAMMA established important advantages over other microchemical methods forin situ analysis at the micron level in histological sections.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1987L016000036 Publication Date 2007-12-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-4984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116796 Serial 8721  
Permanent link to this record
 

 
Author Claes, M.; van Dyck, K.; Deelstra, H.; Van Grieken, R. doi  openurl
  Title Determination of silicon in organic matrices with grazing-emission X-ray fluorescence spectrometry Type A1 Journal article
  Year 1999 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal  
  Volume 54 Issue 10 Pages 1517-1524  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The potential of a prototype grazing-emission X-ray fluorescence spectrometer for reliable analysis of sample solutions, obtained by pressurized microwave oven digestion of Si-spiked organic and biological materials, was investigated as part of an inter-laboratory study. The fact that this grazing-emission technique is based on the total reflection phenomenon and wavelength-dispersive detection, gives it the benefit to determine light elements in a sensitive way. Results of the determination of silicon in pork liver, cellulose, urine, serum, spinach, beer, mineral water and horsetail (dry plant extract) samples are presented. Some of the results are compared with those obtained with other analytical techniques. The study proved that determination of silicon traces in biological matrices represents an extremely difficult task, however, measurements of silicon are achieved with acceptable precision. The most important problems still arise when sample pre-treatment is needed prior to analysis. (C) 1999 Elsevier Science B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000083433600018 Publication Date 2002-08-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0584-8547; 1873-3565 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:25943 Serial 7789  
Permanent link to this record
 

 
Author Thomassen, G.; Van Passel, S.; Alaerts, L.; Dewulf, J. pdf  doi
openurl 
  Title Retrospective and prospective material flow analysis of the post-consumer plastic packaging waste management system in Flanders Type A1 Journal article
  Year 2022 Publication Waste Management Abbreviated Journal Waste Manage  
  Volume 147 Issue Pages 10-21  
  Keywords A1 Journal article; Engineering Management (ENM)  
  Abstract (down) The post-consumer plastic packaging waste management in Flanders was analyzed by performing a retrospective material flow analysis, covering an extensive period from 1985 to 2019. In addition, a prospective material flow analysis of 32 improvement scenarios was performed, based on expected changes in the waste management system. Mass recovery rates were calculated based on different interpretations of the calculation rules. Moreover, various cascading levels were identified to differentiate between the quality level of the secondary applications. The mass recovery rate including only recycling evolved from a value of 0% in 1985 to 31% in 2019 and could be increased to 36-62% depending on the improvement scenario selected. However, the different interpretations of the calculation rules led to a variation of up to 20 and 41% on this mass recovery rates for the retrospective and prospective analysis, respectively. The introduction of monostream recycling for additional post-consumer plastic packaging flows, such as low-density polyethylene, did not lead to increasing mass recovery rates, if no differentiation for the cascading levels was made. The Belgian recycling target of 65% for 2023 will be challenging if the strictest calculation method needs to be followed or if the improvements in the Flemish postconsumer plastic packaging waste system do not follow the best-case collection scenarios under the given assumptions. To harmonize the calculation and monitoring of these targets, clear calculation rules need to be accompanied with a harmonized monitoring system over the entire waste management system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000802961100002 Publication Date 2022-05-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0956-053x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.1 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 8.1  
  Call Number UA @ admin @ c:irua:188651 Serial 7367  
Permanent link to this record
 

 
Author Wang, J. url  openurl
  Title Plasma catalysis : study of CO2 reforming of CH4 in a DBD reactor Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume Issue Pages XVI, 232 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (down) The plasma-based dry reforming in a dielectric barrier discharge (DBD) reactor is important to achieve sustainable goals, but many challenges remain. For example, the conversion and energy yield of DBD reactors are relatively low, and the catalysts or packing materials used in existing studies cannot improve them, possibly due to the unsuitable properties and structures of catalysts or packing materials for plasma processes. In order to study the effect of catalyst structure on plasma-based dry reforming, a controllable synthesis of the catalyst supports or templates was explored. In Chapter 2, an initially immiscible synthesis method was proposed to synthesize uniform silica spheres, which can replace the organic solvent-based Stöber method to successfully synthesize silica particles with the same size ranges as the original Stöber process without addition of organic solvents. Using the silica spheres as templates, 3D porous Cu and CuO catalysts with different pore sizes were synthesized in Chapter 3 to study the effect of catalyst pore size on the plasma-catalytic dry reforming. In most cases, the smaller the pore size, the higher the conversion of CH4 and CO2 due to the reaction of radicals and ions formed in the plasma. An exception are the samples synthesized from 1 μm silica, which show better performance due to the electric field enhancement for pore sizes close to the Debye length. Besides the pore size, the particle diameter of the catalyst or packing is also one of the important factors affecting the interaction between plasma and catalyst. In Chapter 4, SiO2 spheres (with or without supported metal) were used to study the effect of different support particle sizes on plasma-based dry reforming. We found that a uniform SiO2 packing improves the conversion of plasma-based dry reforming. The conversion of plasma-based dry reforming first increases and then decreases with increasing particle size, due to the balance between the promoting and hindering effect of the particle filling on the plasma discharge. Chapter 5 is to improve the design of the DBD reactor itself, in order to try to increase its low energy yield. Some stainless steel rings were put over the inner electrode rod of the DBD reactor. The presence of rings increases the local electric field, the displaced charges and the discharge fraction, and also makes the discharge more stable and with more uniform intensity. The placement of the rings improves the performance of the reactor at 30 W supplied power.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:194045 Serial 7273  
Permanent link to this record
 

 
Author Rojas, C.M.; Goossens, D.; Van Grieken, R. pdf  doi
openurl 
  Title Penetration of atmospheric aerosols during collection in cellulose filters, studied by secondary ion mass spectrometry Type A1 Journal article
  Year 1989 Publication Journal of aerosol science Abbreviated Journal  
  Volume 20 Issue 5 Pages 569-574  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The penetration of aerosol particles in a Whatman-41 cellulose filter has been studied via the depth profiles of different elements present in the aerosol. Depth profiles were obtained by analyzing both fine and coarse fractions from a dichotomous sampler by secondary ion mass spectrometry. The fine particles had an aerodynamic diameter dae of less than 2.5 μm, whereas the coarse fraction had 2.5 ≤ dae ≤ 15 μm. Elements such as Al, Si, Ca, Ti and Fe were associated with coarse airborne particles, while S, Cl, Zn, and Br were more abundant in the fine fraction. Results showed that particle size plays an important role in the distribution of particulate matter throughout the filter. SiTi-containing particles were mostly deposited near the surface of the filter, and their profiles can be estimated using a polynomial function, whereas the profile of AlCaFe-containing particles can be approached by an exponential decay function. Elements associated with fine fraction aerosols mainly originating from combustion processes, can penetrate up to about 25% of the total filter thickness, and their profiles are better represented by a diffusion function.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1989AN60500007 Publication Date 2003-08-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8502; 1879-1964 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116822 Serial 8368  
Permanent link to this record
 

 
Author Sargin, G.O.; Sarikurt, S.; Sevincli, H.; Sevik, C. pdf  url
doi  openurl
  Title The peculiar potential of transition metal dichalcogenides for thermoelectric applications : a perspective on future computational research Type A1 Journal article
  Year 2023 Publication Journal of applied physics Abbreviated Journal  
  Volume 133 Issue 15 Pages 150902-150937  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (down) The peculiar potential transition metal dichalcogenides in regard to sensor and device applications have been exhibited by both experimental and theoretical studies. The use of these materials, thermodynamically stable even at elevated temperatures, particularly in nano- and optoelectronic technology, is about to come true. On the other hand, the distinct electronic and thermal transport properties possessing unique coherency, which may result in higher thermoelectric efficiency, have also been reported. However, exploiting this potential in terms of power generation and cooling applications requires a deeper understanding of these materials in this regard. This perspective study, concentrated with this intention, summarizes thermoelectric research based on transition metal dichalcogenides from a broad perspective and also provides a general evaluation of future theoretical investigations inevitable to shed more light on the physics of electronic and thermal transport in these materials and to lead future experimental research.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001079329000001 Publication Date 2023-04-27  
  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 3.2 Times cited Open Access  
  Notes Approved Most recent IF: 3.2; 2023 IF: 2.068  
  Call Number UA @ admin @ c:irua:200351 Serial 9105  
Permanent link to this record
 

 
Author Van Grieken, R.; Jaenicke, R.; Koutsenogii, K.P.; Khodzher, T.V.; Kulipanov, G.N. openurl 
  Title Atmospheric aerosols in the Asian part of the former Soviet Union Type P1 Proceeding
  Year 2000 Publication AIP conference proceedings T2 – 15th International Conference on Nucleation and Atmospheric Aerosols, (ICNAA), August 06-11, 2000, Univ. Missouri Rolla, Rolla, MO Abbreviated Journal  
  Volume 534 Issue Pages 740-743  
  Keywords P1 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The paper presents the results of the study of atmospheric aerosols in the Siberian region. This research was focused on studying the chemical and biological characteristics of both natural and pollution aerosols in this vast territory of the Asian part of the former Soviet Union (FSU). The data received within the frame of this project formed the basis for the evaluation of the impact of these aerosols on the Arctic region and the global climate. The Asian part of FSU is of scientific interest in the context of environmental chemistry, air pollution and study of atmospheric aerosols, The specific relevance of aerosol research in Siberia is as follows. There are areas that are very remote from industrial or densely populated centres, In these circumstances, aerosol characterization contributes to the definition of global continental “background”) or “baseline” aerosol, i.e, the aerosol which should occur in natural circumstances and on which all pollution is superimposed. Recently, in the context of global and long-term climatic changes, baseline aerosols and long-range transport of particulate air pollutants have become a topic of much debate, This is because it has been thought that aerosols might compensate for the well-known greenhouse effect to a significant. In this context, more and more attention is being paid to long-range effects of continental aerosols on the polar regions. Research in Norway and Alaska showed that Western or Central Siberia may be a very important source of pollutants affecting the air composition in the Arctic region. Cities and regions in south Siberia are enormously polluted by heavy metals, the level of pollution being many times higher than in the Western world, thus the health of local population is seriously affected. In most cases, gigantic point sources are in the area, which is simple from the viewpoint of environmental chemistry and unambiguous results should be obtained easily. Atmospheric deposition is a possible cause of the existence of heavy metals in the southern part of Lake Baikal. in the northern part of the lake, the environment is unpolluted. However in the southern part of the lake is considerably threatened by pollution from Baikalsk wood-pulp mill and industrial enterprises of Irkutsk, Angarsk,  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000089526000168 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1-56396-958-0 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:95766 Serial 7516  
Permanent link to this record
 

 
Author Tummers, A.; Wallert, A.; De Keyser, N. openurl 
  Title Supplementing the eye : the technical analysis of Frans Hals's paintings – ii Type A1 Journal article
  Year 2019 Publication The Burlington magazine Abbreviated Journal  
  Volume 161 Issue 1401 Pages 996-1003  
  Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The painting 'Two fisherboys' has long caused confusion among experts. A close comparison of the painting with a forgery by Han van Meegeren and Frans Hals's `Fisherboy' solves the conundrum and provides valuable insights into the merits and drawbacks of modern analytical techniques.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000500540400006 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0007-6287; 2044-9925 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:165106 Serial 8624  
Permanent link to this record
 

 
Author Sun, C.; Liao, X.; Peng, H.; Zhang, C.; Van Tendeloo, G.; Zhao, Y.; Wu, J. url  doi
openurl 
  Title Interfacial gliding-driven lattice oxygen release in layered cathodes Type A1 Journal article
  Year 2022 Publication Cell reports physical science Abbreviated Journal  
  Volume 3 Issue 1 Pages  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract (down) The oxygen release of layered cathodes causes many battery failures, but the underlying mechanism in an actual working cathode is still elusive as it involves secondary agglomerates that introduce complicated boundary structures. Here, we report a general structure instability on the mismatch boundaries driven by interfacial gliding-it introduces a shear stress causing a distortion of the metal-oxygen octahedra framework that reduces its kinetic stability. The migration of cations and diffusion of oxygen vacancies continue to degrade the whole particle from the boundary to the interior, followed by the formation of nano-sized cracks on the fast-degrading interfaces. This work reveals a robust chemical and mechanical interplay on the oxygen release inherent to the intergranular boundaries of layered cathodes. It also suggests that radially patterned columnar grains with low-angle planar boundaries would be an efficient approach to mitigate the boundary oxygen release.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000745659500012 Publication Date 2021-12-20  
  Series Editor 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 OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:186420 Serial 6961  
Permanent link to this record
 

 
Author Rezaei, M.; Ghasemitarei, M.; Razzokov, J.; Yusupov, M.; Ghorbanalilu, M.; Ejtehadi, M.R. pdf  doi
openurl 
  Title In silico study of the impact of oxidation on pyruvate transmission across the hVDAC1 protein channel Type A1 Journal article
  Year 2024 Publication Archives of biochemistry and biophysics Abbreviated Journal  
  Volume 751 Issue Pages 109835-109837  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (down) The overexpression of voltage dependent anion channels (VDACs), particularly VDAC1, in cancer cells compared to normal cells, plays a crucial role in cancer cell metabolism, apoptosis regulation, and energy homeostasis. In this study, we used molecular dynamics (MD) simulations to investigate the effect of a low level of VDAC1 oxidation (induced e.g., by cold atmospheric plasma (CAP)) on the pyruvate (Pyr) uptake by VDAC1. Inhibiting Pyr uptake through VDAC1 can suppress cancer cell proliferation. Our primary target was to study the translocation of Pyr across the native and oxidized forms of hVDAC1, the human VDAC1. Specifically, we employed MD simulations to analyze the hVDAC1 structure by modifying certain cysteine residues to cysteic acids and methionine residues to methionine sulfoxides, which allowed us to investigate the effect of oxidation. Our results showed that the free energy barrier for Pyr translocation through the native and oxidized channel was approximately 4.3 +/- 0.7 kJ mol-1 and 10.8 +/- 1.8 kJ mol-1, respectively. An increase in barrier results in a decrease in rate of Pyr permeation through the oxidized channel. Thus, our results indicate that low levels of CAP oxidation reduce Pyr translocation, resulting in decreased cancer cell proliferation. Therefore, low levels of oxidation are likely sufficient to treat cancer cells given the inhibition of Pyr uptake.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001127850500001 Publication Date 2023-11-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-9861; 1096-0384 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 3.9 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.9; 2024 IF: 3.165  
  Call Number UA @ admin @ c:irua:202185 Serial 9046  
Permanent link to this record
 

 
Author Gielis, J.; Tavkhelidze, I. url  doi
openurl 
  Title The general case of cutting of Generalized Möbius-Listing surfaces and bodies Type A1 Journal article
  Year 2020 Publication 4Open Abbreviated Journal  
  Volume 3 Issue Pages 7-48  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (down) The original motivation to study Generalized Möbius-Listing GML surfaces and bodies was the observation that the solution of boundary value problems greatly depends on the domains. Since around 2010 GML’s were merged with (continuous) Gielis Transformations, which provide a unifying description of geometrical shapes, as a generalization of the Pythagorean Theorem. The resulting geometrical objects can be used for modeling a wide range of natural shapes and phenomena. The cutting of GML bodies and surfaces, with the Möbius strip as one special case, is related to the field of knots and links, and classifications were obtained for GML with cross sectional symmetry of 2, 3, 4, 5 and 6. The general case of cutting GML bodies and surfaces, in particular the number of ways of cutting, could be solved by reducing the 3D problem to planar geometry. This also unveiled a range of connections with topology, combinatorics, elasticity theory and theoretical physics.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2020-08-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2557-0250 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:174471 Serial 7992  
Permanent link to this record
 

 
Author Gonzalez-Nelson, A.; Mula, S.; Simenas, M.; Balciunas, S.; Altenhof, A.R.; Vojvodin, C.S.; Canossa, S.; Banys, J.; Schurko, R.W.; Coudert, F.-X.; van der Veen, M.A. url  doi
openurl 
  Title Emergence of coupled rotor dynamics in metal-organic frameworks via tuned steric interactions Type A1 Journal article
  Year 2021 Publication Journal Of The American Chemical Society Abbreviated Journal J Am Chem Soc  
  Volume 143 Issue 31 Pages 12053-12062  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract (down) The organic components in metal-organic frameworks (MOFs) are unique: they are embedded in a crystalline lattice, yet, as they are separated from each other by tunable free space, a large variety of dynamic behavior can emerge. These rotational dynamics of the organic linkers are especially important due to their influence over properties such as gas adsorption and kinetics of guest release. To fully exploit linker rotation, such as in the form of molecular machines, it is necessary to engineer correlated linker dynamics to achieve their cooperative functional motion. Here, we show that for MIL-53, a topology with closely spaced rotors, the phenylene functionalization allows researchers to tune the rotors' steric environment, shifting linker rotation from completely static to rapid motions at frequencies above 100 MHz. For steric interactions that start to inhibit independent rotor motion, we identify for the first time the emergence of coupled rotation modes in linker dynamics. These findings pave the way for function-specific engineering of gear-like cooperative motion in MOFs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000684581100022 Publication Date 2021-07-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0002-7863 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.858 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 13.858  
  Call Number UA @ admin @ c:irua:180504 Serial 6867  
Permanent link to this record
 

 
Author Hellar-Kihampa, H.; De Wael, K.; Lugwisha, E.; Van Grieken, R. pdf  doi
openurl 
  Title Water quality assessment in Pangani river basin, Tanzania : natural and anthropogenic influences on concentrations of nutrients and inorganic ions Type A1 Journal article
  Year 2013 Publication International journal of river basin management Abbreviated Journal  
  Volume 11 Issue 1 Pages 55-75  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract (down) The ongoing rapid expansions of human activities and population dynamics have potential impact on the environmental quality of the Pangani river basin, one of the largest water resources in Tanzania, including possible loadings of different kinds of micro-contaminants. However, specific extents of the impacts are rather not well investigated. In this work, we assessed the environmental quality of the basin, based on seasonal characterisation of physicochemical water and sediments parameters, dissolved inorganic ions and nutrient loads. The contributions of geochemical processes and land-use practices were evaluated by multivariate correlations and principal component analysis (PCA). Hierarchical cluster analysis was used to classify similar water quality stations and identify the most and least enriched ones. Surface waters were slightly alkaline, characterised by low total dissolved solids (48652 mg/L). Extremely low oxygen concentration (2.0 mg/L) was also a cause of concern at one station. The Na+ and HCO3 − ions provided the dominant cation and anion, respectively. PCA identified weathering of carbonate and Na+ bearing rocks, gypsum dissolution and atmospheric deposition of sea-salt as the major factors controlling the ionic composition, contributing more than 60% of the spatial variance. Concentration profiles of the chemical species showed a generally low level of anthropogenic inputs, except at a few locations where nitrate and nitrite were significantly enriched above the limits of safe exposure, with patterns indicating influences of farming and livestock keeping. A seasonal difference was observed, with lower ion concentrations during the rainy season, likely due to the dilution effect of increased water discharge. The study provides new insights into the environmental quality of the basin, and indicates the need for continuous monitoring and assessment of the chemical species in the area.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2013-01-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1571-5124 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:104621 Serial 5909  
Permanent link to this record
 

 
Author Larraín, M.; Billen, P.; Cifuentes, L.; Van Passel, S. pdf  doi
openurl 
  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 (down) 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 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 Sebhatu, K.T.; Gezahegn, T.W.; Berhanu, T.; Maertens, M.; Van Passel, S.; D'Haese, M. url  doi
openurl 
  Title Exploring variability across cooperatives : economic performance of agricultural cooperatives in northern Ethiopia Type A1 Journal article
  Year 2021 Publication The international food and agribusiness management review Abbreviated Journal  
  Volume 24 Issue 3 Pages 397-419  
  Keywords A1 Journal article; Engineering Management (ENM)  
  Abstract (down) The number of agricultural cooperatives increased quickly in Ethiopia since the 1990s. While many papers studied the impact of membership of Ethiopian cooperatives, not much is known on their performance. This study takes a cooperative-level perspective which is unique in an African context. It compares the economic performance proxied by sales revenue and profit of a wide range of agricultural cooperatives in northern Ethiopia. Data were collected from 511 agricultural cooperatives in 12 districts of Tigray. The contributing factors of the performance are analyzed with Ordinary Least Squares regression (OLS) and Heckman selection models. Our results underscore the importance of membership size, total assets, presence of conflict among members, and union membership. Chairperson characteristics and the internal organization of a cooperative seem to be less correlated to performance.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000645416400002 Publication Date 2021-03-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1096-7508; 1559-2448 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:179025 Serial 6923  
Permanent link to this record
 

 
Author Zhang, L.; Quinn, B.K.; Hui, C.; Lian, M.; Gielis, J.; Gao, J.; Shi, P. url  doi
openurl 
  Title New indices to balance α-diversity against tree size inequality Type A1 Journal article
  Year 2024 Publication Journal of forestry research Abbreviated Journal  
  Volume 35 Issue 1 Pages 31-39  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (down) The number and composition of species in a community can be quantified with alpha-diversity indices, including species richness (R), Simpson's index (D), and the Shannon-Wiener index (HGREEK TONOS). In forest communities, there are large variations in tree size among species and individuals of the same species, which result in differences in ecological processes and ecosystem functions. However, tree size inequality (TSI) has been largely neglected in studies using the available diversity indices. The TSI in the diameter at breast height (DBH) data for each of 999 20 m x 20 m forest census quadrats was quantified using the Gini index (GI), a measure of the inequality of size distribution. The generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per quadrat. We also examined the relationships of alpha-diversity indices with the GI using correlation tests. The generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions, with most root-mean-square errors (990 out of 999 quadrats) being < 0.0030. There were significant positive correlations between each of three alpha-diversity indices (i.e., R, D, and H') and the GI. Nevertheless, the total abundance of trees in each quadrat did not significantly influence the GI. This means that the TSI increased with increasing species diversity. Thus, two new indices are proposed that can balance alpha-diversity against the extent of TSI in the community: (1 – GI) x D, and (1 – GI) x H'. These new indices were significantly correlated with the original D and HGREEK TONOS, and did not increase the extent of variation within each group of indices. This study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities, especially in the face of cumulative species loss under global climate change.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001131698000001 Publication Date 2023-12-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1007-662x; 1993-0607 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 3 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3; 2024 IF: 0.774  
  Call Number UA @ admin @ c:irua:201972 Serial 9061  
Permanent link to this record
 

 
Author Jiang, J. file  openurl
  Title Ginzburg-Landau dynamical simulations on the nonreciprocal transport properties of two-dimensional superconductors Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume Issue Pages XII, 79 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract (down) The nonreciprocal charge transport property which depends on the polarity of the applied current, such as the diode effect and the rectification effect, is of great importance for both theoretical research and engineering application. The nonreciprocal transport property in superconductors generally requires to break both the spatial inversion symmetry and the time-reversal symmetry, and therefore becomes one of the fundamental issues in superconductivity. Of particular interest, the superconducting diode effect, which exhibits one-way superconductivity, can potentially be applied to dissipationless diode devices, as a consequence has received extensive attention in recent years. In this Ph. D thesis, we simulate vortex dynamics with heat dissipation by numerically solving time-dependent Ginzburg-Landau equations and heat transfer equation. The nonreciprocal transport properties of the following three superconducting systems are studied. We study a superconducting film patterned with a conformal pinning array and find a giant rectification effect which is consistent with the experimental observation. In presence of the funneling effect due to the geometry of the conformal pinning array, Joule heating of the accumulating vortices creates hot spots and drives the sample to the normal state. Meanwhile, the density gradient of vortex does not match the gradient of pinning. The two mechanisms together lead to the giant rectification effect. We study the nonreciprocal charge transport property in a pinning-free superconducting nano-ring. We systematically calculate the response of the ratchet signal to various parameters in both D.C. and A.C. currents. By analyzing the vortex potential, we find that the nonreciprocal transport property is caused by the asymmetry potential barriers for vortex entry and exit. We study a superconductor/nanoscale-magnetic-dot hybrid structure. It takes advantage of the external current to control the nucleation of vortex-antivortex pairs, and can produce superconducting diode effect without applied magnetic fields. Our vortex dynamics simulation details the progress of the superconducting-normal phase transition due to motion of vortex pairs and heat dissipation. The nonreciprocal transport properties of the above three systems are all based on the broken symmetry of spatial inversion, which is caused by the anisotropic pinning array, the asymmetric geometry, and the nonuniform distribution of the magnetic field, respectively. The mechanisms we discuss in this thesis do not require special property of the materials and thus can be applied to any kinds of conventional superconductors. The present studies would provide solid theoretical basis for the future design and application of the dissipationless superconducting devices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:188525 Serial 7168  
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Author Gonzalez, V.; Fazlic, I.; Cotte, M.; Vanmeert, F.; Gestels, A.; De Meyer, S.; Broers, F.; Hermans, J.; van Loon, A.; Janssens, K.; Noble, P.; Keune, K. url  doi
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  Title Lead(II) formate in Rembrandt's Night Watch : detection and distribution from the macro- to the micro-scale Type A1 Journal article
  Year 2023 Publication Angewandte Chemie: international edition in English Abbreviated Journal  
  Volume Issue Pages 1-9  
  Keywords A1 Journal article; Art; Antwerp X-ray Imaging and Spectroscopy (AXIS)  
  Abstract (down) The Night Watch, painted in 1642 and on view in the Rijksmuseum in Amsterdam, is considered Rembrandt's most famous work. X-ray powder diffraction (XRPD) mapping at multiple length scales revealed the unusual presence of lead(II) formate, Pb(HCOO)(2), in several areas of the painting. Until now, this compound was never reported in historical oil paints. In order to get insights into this phenomenon, one possible chemical pathway was explored thanks to the preparation and micro-analysis of model oil paint media prepared by heating linseed oil and lead(II) oxide (PbO) drier as described in 17(th) century recipes. Synchrotron radiation based micro-XRPD (SR-mu-XRPD) and infrared microscopy were combined to identify and map at the micro-scale various neo-formed lead-based compounds in these model samples. Both lead(II) formate and lead(II) formate hydroxide Pb(HCOO)(OH) were detected and mapped, providing new clues regarding the reactivity of lead driers in oil matrices in historical paintings.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000920584500001 Publication Date 2023-01-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1433-7851; 0570-0833 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 16.6 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 16.6; 2023 IF: 11.994  
  Call Number UA @ admin @ c:irua:194279 Serial 7318  
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