Records |
Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kuczumow, A.; Vekemans, B.; Schalm, O.; Vincze, L.; Dorriné, W.; Gysels, K.; Van Grieken, R. |
Title |
Some new applications of auxiliary signals in X-ray fluorescence and electron microprobe analysis |
Type |
P1 Proceeding |
Year |
1999 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
197-201
T2 - Proceedings of the European Conferenc |
Keywords |
P1 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Wos |
000081658400032 |
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Additional Links |
UA library record; WoS full record |
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Open Access |
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no |
Call Number |
UA @ admin @ c:irua:24716 |
Serial |
8553 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kulkarni, S.; Gonzalez-Quiroga, A.; Nuñez, M.; Schuerewegen, C.; Perreault, P.; Goel, C.; Heynderickx, G.J.; Van Geem, K.M.; Marin, G.B. |
Title |
An experimental and numerical study of the suppression of jets, counterflow, and backflow in vortex units |
Type |
A1 Journal article |
Year |
2019 |
Publication |
AIChE journal |
Abbreviated Journal |
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Volume |
65 |
Issue |
8 |
Pages |
e16614-13 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Vortex units are commonly considered for various single and multiphase applications due to their process intensification capabilities. The transition from gas‐only flow to gas–solid flow remains largely unexplored nonetheless. During this transition, primary flow phenomenon, jets, and secondary flow phenomena, counterflow and backflow, are substantially reduced, before a rotating solids bed is established. This transitional flow regime is referred to as the vortex suppression regime. In the present work, this flow transition is identified and validated through experimental and computational studies in two vortex units with a scale differing by a factor of 2, using spherical aluminum and alumina particles. This experimental data supports the proposed theoretical particle monolayer solids loading that allows estimation of vortex suppression regime solids capacity for any vortex unit. It is shown that the vortex suppression regime is established at a solids loading theoretically corresponding to a monolayer being formed in the unit for 1g‐Geldart D‐ and 1g‐Geldart B‐type particles. The model closely agrees with experimental vortex suppression range for both aluminum and alumina particles. The model, as well as the experimental data, shows that the flow suppression regime depends on unit dimensions, particle diameter, and particle density but is independent of gas flow rate. This combined study, based on experimental and computational data and on a theoretical model, reveals the vortex suppression to be one of the basic operational parameters to study flow in a vortex unit and that a simple monolayer model allows to estimate the needed solids loading for any vortex device to induce this flow transition. |
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Wos |
000474620800026 |
Publication Date |
2019-04-19 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0001-1541 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Open Access |
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no |
Call Number |
UA @ admin @ c:irua:162121 |
Serial |
7945 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kumar, M.; Sengupta, A.; Kummamuru, N.B. |
Title |
Molecular simulations for carbon dioxide capture in silica slit pores |
Type |
A3 Journal article |
Year |
2023 |
Publication |
Materials Today: Proceedings |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-9 |
Keywords |
A3 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
In present work, we have performed the Grand Canonical Monte Carlo (GCMC) simulations to quantify CO2 capture inside porous silica at high operating temperatures of 673.15 K and 873.15 K; and over a operating pressure range of 500 kPa – 4000 kPa that are methane steam reforming process parameters. Related chemical potential values at these thermodynamic conditions are obtained from the bulk phase simulations in the Canonical ensemble in conjunction with Widom’s insertion technique, where the CO2 has been accurately represented by TraPPE force field. Present structure of the porous silica is a single slit pore geometry of various heights (H = 20 Å, 31.6 Å, 63.2 Å and 126.5 Å), dimensions in which possible vapour-liquid equilibria for generic square well fluids has been reported in literature. Estimation of the pore-fluid interactions show a higher interaction between silica pore and adsorbed CO2 compared to the reported pore-fluid interactions between homogeneous carbon slit pore and adsorbed CO2; thus resulting in an enhancement of adsorption inside silica pores of H = 20 Å and H = 126.5 Å, which are respectively 3.5 times and 1.5 times higher than that in homogeneous carbon slit pores of same dimensions and at 673.15 K and 500 kPa. Estimated local density plots indicate the presence of structured layers due to more molecular packing, which confirms possible liquid-like and vapour-like phase coexistence of the supercritical bulk phase CO2 under confinement. |
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Publication Date |
2023-05-06 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2214-7853 |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:200944 |
Serial |
9058 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kummamuru, N.B. |
Title |
Methane and hydrogen storage in clathrate hydrates |
Type |
Doctoral thesis |
Year |
2024 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
XXV, 260 p. |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS) |
Abstract |
In a world increasingly reliant on alternative energy sources, the quest for efficient and secure storage solutions is paramount. This doctoral thesis explores the exciting potential of a familiar material – water – to act as a vault for next-generation energy sources like hydrogen (H2) and methane (CH4). Nature offers a solution in the form of clathrate hydrates, fascinating cage-like structures formed from water molecules that can trap these gas molecules within their framework. This research investigates on improving the formation kinetics and gas storage capabilities of clathrate hydrates utilizing porous materials and the interstitial space between non-porous materials to augment the contact between gas and water thereby catalysing the growth of hydrates and unlocking their full potential as efficient and secure energy storage reservoirs. A key outcome of this research is the formulation of an empirical correlation, offering predictive insights into CH4 hydrate phase equilibrium conditions. Innovative approaches utilizing thermally conductive beads have yielded substantial enhancements in CH4 uptake. Furthermore, the identification of optimal water content within porous materials showcases a pathway to maximize CH4 storage capacity and hydrate growth kinetics. In the domain of hydrogen storage, attention is also directed towards unstirred systems, where the integration of functionalized porous materials has demonstrated a significant improvement in the rate of hydrate formation and the overall H2 storage capacity. A noteworthy achievement of this research lies in the successful storage of H2 within confined CH4 hydrates through a gas exchange process and the preliminary results show the potential for safer and more sustainable method for H2 storage at mild thermodynamic conditions, offering promising prospects for future energy systems. |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:206258 |
Serial |
9160 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kummamuru, N.B.; Ciocarlan, R.-G.; Houlleberghs, M.; Martens, J.; Breynaert, E.; Verbruggen, S.W.; Cool, P.; Perreault, P. |
Title |
Surface modification of mesostructured cellular foam to enhance hydrogen storage in binary THF/H₂ clathrate hydrate |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Sustainable energy & fuels |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-15 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Laboratory of adsorption and catalysis (LADCA) |
Abstract |
This study introduces solid-state tuning of a mesostructured cellular foam (MCF) to enhance hydrogen (H-2) storage in clathrate hydrates. Grafting of promoter-like molecules (e.g., tetrahydrofuran) at the internal surface of the MCF resulted in a substantial improvement in the kinetics of formation of binary H-2-THF clathrate hydrate. Identification of the confined hydrate as sII clathrate hydrate and enclathration of H-2 in its small cages was performed using XRD and high-pressure H-1 NMR spectroscopy respectively. Experimental findings show that modified MCF materials exhibit a similar to 1.3 times higher H-2 storage capacity as compared to non-modified MCF under the same conditions (7 MPa, 265 K, 100% pore volume saturation with a 5.56 mol% THF solution). The enhancement in H-2 storage is attributed to the hydrophobicity originating from grafting organic molecules onto pristine MCF, thereby influencing water interactions and fostering an environment conducive to H-2 enclathration. Gas uptake curves indicate an optimal tuning point for higher H-2 storage, favoring a lower density of carbon per nm(2). Furthermore, a direct correlation emerges between higher driving forces and increased H-2 storage capacity, culminating at 0.52 wt% (46.77 mmoles of H-2 per mole of H2O and 39.78% water-to-hydrate conversions) at 262 K for the modified MCF material with fewer carbons per nm(2). Notably, the substantial H-2 storage capacity achieved without energy-intensive processes underscores solid-state tuning's potential for H-2 storage in the synthesized hydrates. This study evaluated two distinct kinetic models to describe hydrate growth in MCF. The multistage kinetic model showed better predictive capabilities for experimental data and maintained a low average absolute deviation. This research provides valuable insights into augmenting H-2 storage capabilities and holds promising implications for future advancements. |
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Wos |
001208396000001 |
Publication Date |
2024-04-15 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205764 |
Serial |
9232 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kuppens, T.; Van Dael, M.; Maggen, J.; Vanreppelen, K.; Yperman, J.; Carleer, R.; Elen, H.; Van Passel, S. |
Title |
Techno-economic assessment of different conversion pathways for pyrolysis char from pig manure |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
901-911 |
Keywords |
P1 Proceeding; Engineering sciences. Technology |
Abstract |
The amount of animal manure that can be brought back to agricultural land is limited by legislation. Because pig manure is available in too large quantities in some areas, we investigate the techno-economic feasibility of converting it into valuable products. First, slurry is separated in water, a thick fraction and a fertilizer concentrate poor in phosphate. Then, the thick fraction is dried and pyrolyzed. Our goal is to identify the optimal pyrolysis and activation conditions for the production of biochar or activated carbon. The latter has interesting adsorption characteristics due to the presence of nitrogen. It can also be used as a soil amendment as it improves biomass quantity and quality. On top, it immobilizes toxic elements and stores carbon in the soil. Char thus has many interesting characteristics and can be valued in different ways. The economic feasibility has been explored by a first techno-economic modelling iteration. The critical factors influencing the feasibility are identified by Monte Carlo simulations for further improvement of the process design. |
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Abbreviated Series Title |
22nd European Biomass Conference and Exhibition : Setting the Course for a Biobased Economy, 23-26 June 2014, Hamburg, Germany : conference proceedings |
Series Volume |
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Series Issue |
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Edition |
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ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:127546 |
Serial |
6263 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Kuppens, T.; Van Dael, M.; Vanreppelen, K.; Carleer, R.; Yperman, J.; Schreurs, S.; Van Passel, S. |
Title |
Techno-economic assessment of pyrolysis char production and application : a review |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
67-72 |
Keywords |
P1 Proceeding; Engineering sciences. Technology |
Abstract |
Many organic residue streams such as pig manure are not or inefficiently used, although they can be converted into valuable materials, as well as energy, using pyrolysis. The yield of the pyrolysis products (i.e. oil, gas and char) is dependent on the process conditions and the feedstock used. Char as a soil amendment or activated carbon are interesting options for valorization of biomass residues. Here, a review is presented of the techno-economic potential of both valorization options based on literature and own experiments with wood from phytoremediation, particle board and waste from beer production. The term “biochar” is specifically used to designate pyrolysis char that is intentionally applied to soil in order to enhance its structure and fertility. Biochar applications are often also motivated by the objective of climate change mitigation. Two main disadvantages for the economic feasibility of biochar applications have been discerned. Firstly, carbon sequestration in agricultural crops and soils is not yet eligible under the Clean Development Mechanism. Secondly, the impact of biochar on crop productivity is unclear. Activated carbon (AC) seems to have interesting adsorption characteristics resulting in potentially high sales prices. A preliminary techno-economic assessment showed that AC production is preferred above oil production for wood from phytoremediation as long as the market price of 2 kEUR.t(-1) for commercially available ACs can be attained. Whenever a feedstock with high nitrogen content is available (e.g. particle board with melamine urea formaldehyde resin), even higher market prices might be attained. This study shows that valorization of the pyrolysis char might be an answer to the slow adoption of pyrolysis in commercial applications. Focus in research and development, for instance in future research with regard to pig manure valorization, should therefore be on sustainable products with high economic value and direct utilization potential. |
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Wos |
000346540000012 |
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Series Title |
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Abbreviated Series Title |
International Conference on BioMass (iconBM 2014), 4-7 May 2014, Florence, Italy / Ranzi, Eliseo [edit.]; et al. |
Series Volume |
37 |
Series Issue |
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Edition |
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ISSN |
978-88-95608-28-0 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
8 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:127547 |
Serial |
6265 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Labey, E.; Fonteyn, F.; Wilmot, A.; El Amouri, S.; Gjurova, A.; De Cock, W.; De Wael, F. |
Title |
Shaping utopia through law: how the law does (not) provide an answer to societal challenges |
Type |
ME2 Book as editor or co-editor |
Year |
2023 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
210 p. |
Keywords |
ME2 Book as editor or co-editor; Law; Government and Law |
Abstract |
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Thesis |
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Wos |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
978-94-000-1654-5 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:198938 |
Serial |
9227 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
LaBrecque, J.J.; Beusen, J.M.; Van Grieken, R.E. |
Title |
Analysis of lateritic material from Cerro impacto by instrumental neutron activation employing a low-energy photon semiconductor and a high-energy Ge(Li) detector |
Type |
A1 Journal article |
Year |
1986 |
Publication |
Applied spectroscopy |
Abbreviated Journal |
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Volume |
40 |
Issue |
2 |
Pages |
140-144 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Nineteen elements were determined in four different grain size fractions of a bulk geological material from Cerro Impacto for a study of the physical (mechanical) concentration process of different elements based upon the hardness of the different minerals. The analysis was performed by excitation of the sample with a high, slow neutron flux followed by gamma-ray spectroscopy with both a conventional Ge(Li) high-energy detector and a low-energy photon detector (LEPD). The accuracy of this method was studied with the use of two standard reference materials, SY-2 and SY-3, which are similar to the real samples. The values determined were also compared with a secondary target x-ray fluorescence method for all the elements that were suitable to both methods. Actually, the x-ray fluorescence method was found to be more complementary than competitive. |
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Wos |
A1986A085900003 |
Publication Date |
2005-07-21 |
Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-7028 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116768 |
Serial |
7448 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Labrecque, J.J.; Beusen, J.M.; Van Grieken, R.E. |
Title |
Determination of barium, lanthanum, cerium and neodymium in lateritic materials by various energy-dispersive X-ray fluorescence techniques and neutron activation analysis |
Type |
A1 Journal article |
Year |
1986 |
Publication |
X-ray spectrometry |
Abbreviated Journal |
|
Volume |
15 |
Issue |
1 |
Pages |
13-18 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A comparison of four methods for the determination of barium, lanthanum, cerium and neodymium in lateritic materials from Brazil is presented. Three of the methods were based on x-ray fluorescence (XRF) spectroscopy: two by radioisotope excitation (Co-57 and Am-241) and one by secondary target XRF (a molybdenum target with a tungsten anode). The other method was based on neutron activation analysis employing both a Ge(Li) coaxial detector and a high-purity germanium detector. The results from these four methods were similar for lanthanum, cerium and neodymium, but for barium at low concentrations (<500 ppm) the neutron activation and the secondary target XRF methods were not suitable. Data on the precision and accuracy of these methods using a series of standard reference rocks are given. The advantages and limitations of each of these methods with respect to the analysis of lateritic materials are discussed. |
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Wos |
A1986AYN6000003 |
Publication Date |
2005-05-28 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0049-8246 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116487 |
Serial |
7774 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lachmann, T.; van der Snickt, G.; Haschke, M.; Mantouvalou, I. |
Title |
Combined 1D, 2D and 3D micro-XRF techniques for the analysis of illuminated manuscripts |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
|
Volume |
31 |
Issue |
10 |
Pages |
1989-1997 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The combination of several micro-XRF analysis modes is presented for the investigation of an illuminated parchment manuscript. With a commercial instrument, conventional micro-XRF spot analysis (0D) and mapping (2D) are performed, yielding detailed lateral elemental information. Depth resolution becomes accessible by mounting an additional polycapillary lens in front of an SDD detector. Quantitative confocal depth profiles (1D) are presented as well as the full separation of the front and the backside decorations with the help of fast 3D mappings of specific areas. Only through the use of these multidimensional modes can elemental information be assigned both to lateral and depth positions, making the analysis of such heterogeneous samples feasible. |
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Wos |
000385362200004 |
Publication Date |
2016-08-25 |
Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0267-9477 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:144755 |
Serial |
7679 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lamoen, D.; Michel, K.H. |
Title |
Crystal field and molecular structure of solid C60 |
Type |
A1 Journal article |
Year |
1993 |
Publication |
Zeitschrift für Physik : B : condensed matter |
Abbreviated Journal |
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Volume |
92 |
Issue |
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Pages |
323-330 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The crystal field in the orientationally disordered phase of C90-fullerite is derived from an intermolecular potential model, which takes into account the geometric difference between double bonds and single bonds. The molecules are modelled as rigid bodies, atoms and single bonds are treated as single interaction centers, while double bonds are described by a distribution of interaction centers along the bond. The crystal field is expanded in terms of cubic rotator functions. The calculated expansion coefficients are compared with empirical values derived from diffraction data. The angular dependence of the crystal field, resulting from an anticlockwise rotation of the molecule around the [111] axis, exhibits an absolute and a secondary minimum at angles of 98-degrees and 38-degrees respectively. The self interaction of the molecule in a deformable lattice is investigated. |
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Place of Publication |
Berlin |
Editor |
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Wos |
A1993MC88000005 |
Publication Date |
2005-03-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0722-3277;1434-6036; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
25 |
Open Access |
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Notes |
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Approved |
PHYSICS, CONDENSED MATTER 11/54 Q1 # |
Call Number |
UA @ lucian @ c:irua:5777 |
Serial |
553 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lamoen, D.; Michel, K.H. |
Title |
Molecular structure, crystal field and orientational order in solid C60 |
Type |
H1 Book chapter |
Year |
1994 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
183-202 |
Keywords |
H1 Book chapter; Condensed Matter Theory (CMT) |
Abstract |
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Place of Publication |
s.l. |
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Wos |
A1994BE86T00011 |
Publication Date |
0000-00-00 |
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Series Volume |
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Edition |
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ISSN |
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ISBN |
0-7923-3109-5 |
Additional Links |
UA library record; WoS full record; |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
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Call Number |
UA @ lucian @ c:irua:9355 |
Serial |
2186 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Larraín, M. |
Title |
Recycling of plastics : linking technical, economic and policy aspects of post-consumer plastic packaging |
Type |
Doctoral thesis |
Year |
2022 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
x, 165 p. |
Keywords |
Doctoral thesis; Engineering sciences. Technology; Engineering Management (ENM); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) |
Abstract |
The rise in plastic packaging production and disposal has encouraged the progress of recycling technologies and aroused policy discussion on how to increase recycling rates. However, the effect that these policy instruments will have on the development of the different recycling technologies has not been studied holistically yet. This dissertation explores how new and existing technologies will behave under the market and policy conditions observed at present and after the implementation of the policy instruments that are under discussion. The technologies that are analyzed in this thesis are mechanical recycling and thermochemical recycling of post-consumer polyolefin waste. Using a techno-economic assessment that takes into account the physical properties of the different plastic fractions and their contamination level, the study shows that both mechanical and thermochemical recycling can be profitable if oil prices remain steady or increase. Specifically, mechanical recycling will show better results than thermochemical recycling for plastic fractions with low contamination levels. On the contrary, thermochemical recycling is more profitable for fractions with a higher contamination level from which high-quality products cannot be obtained with mechanical recycling, such as PE films. Moreover, it demonstrates that besides the oil prices and sorted waste prices, waste purity and the plant capacity are the variables that influence more the net present value of thermochemical recycling and the labor cost and waste purity the ones of mechanical recycling. The thesis explores the dynamics between the stakeholders of the circular value chain and predicts the recycling rates under the implementation of several policy instruments. This is done with a supply chain equilibrium model, based on the extended producer responsibility scheme implemented in Flanders, that uses as an input the cost structures of mechanical and thermochemical recycling obtained from the techno-economic assessments. Direct interventions like recycled content standards, can decouple the recycling industry from the oil market, but in the long term, they may not present incentives to achieve recycling levels beyond the targeted amounts and thus limit technological innovation. On the contrary, economic interventions such as taxes, create economic incentives for recycling and allow fund collection from the government but leave the recycled levels dependent on external markets. Results also show that higher recycling rates does not necessarily mean better environmental performance. Therefore, when designing circular economy policies, policymakers should carefully analyze whether the intention is to increase circularity or improve the sustainability of the value chains. |
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ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:191730 |
Serial |
7366 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lavor, I.R.; da Costa, D.R.; Covaci, L.; Milošević, M.V.; Peeters, F.M.; Chaves, A. |
Title |
Zitterbewegung of moiré excitons in twisted MoS₂/WSe₂ heterobilayers |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical review letters |
Abbreviated Journal |
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Volume |
127 |
Issue |
10 |
Pages |
106801 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
The moire pattern observed in stacked noncommensurate crystal lattices, such as heterobilayers of transition metal dichalcogenides, produces a periodic modulation of their band gap. Excitons subjected to this potential landscape exhibit a band structure that gives rise to a quasiparticle dubbed the moire exciton. In the case of MoS2/WSe2 heterobilayers, the moire trapping potential has honeycomb symmetry and, consequently, the moire exciton band structure is the same as that of a Dirac-Weyl fermion, whose mass can be further tuned down to zero with a perpendicularly applied field. Here we show that, analogously to other Dirac-like particles, the moire exciton exhibits a trembling motion, also known as Zitterbewegung, whose long timescales are compatible with current experimental techniques for exciton dynamics. This promotes the study of the dynamics of moire excitons in van der Waals heterostructures as an advantageous solid-state platform to probe Zitterbewegung, broadly tunable by gating and interlayer twist angle. |
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Place of Publication |
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Wos |
000692200800020 |
Publication Date |
2021-08-31 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1079-7114 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
5 |
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:181599 |
Serial |
6896 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Le Compte, M.; Cardenas De La Hoz, E.; Peeters, S.; Rodrigues Fortes, F.; Hermans, C.; Domen, A.; Smits, E.; Lardon, F.; Vandamme, T.; Lin, A.; Vanlanduit, S.; Roeyen, G.; van Laere, S.; Prenen, H.; Peeters, M.; Deben, C. |
Title |
Single-organoid analysis reveals clinically relevant treatment-resistant and invasive subclones in pancreatic cancer |
Type |
A1 Journal article |
Year |
2023 |
Publication |
npj Precision Oncology |
Abbreviated Journal |
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Volume |
7 |
Issue |
1 |
Pages |
128-14 |
Keywords |
A1 Journal article; Center for Oncological Research (CORE); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC) |
Abstract |
Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal diseases, characterized by a treatment-resistant and invasive nature. In line with these inherent aggressive characteristics, only a subset of patients shows a clinical response to the standard of care therapies, thereby highlighting the need for a more personalized treatment approach. In this study, we comprehensively unraveled the intra-patient response heterogeneity and intrinsic aggressive nature of PDAC on bulk and single-organoid resolution. We leveraged a fully characterized PDAC organoid panel ( N = 8) and matched our artificial intelligence-driven, live-cell organoid image analysis with retrospective clinical patient response. In line with the clinical outcomes, we identified patient-specific sensitivities to the standard of care therapies (gemcitabine-paclitaxel and FOLFIRINOX) using a growth rate-based and normalized drug response metric. Moreover, the single-organoid analysis was able to detect resistant as well as invasive PDAC organoid clones, which was orchestrates on a patient, therapy, drug, concentration and time-specific level. Furthermore, our in vitro organoid analysis indicated a correlation with the matched patient progression-free survival (PFS) compared to the current, conventional drug response readouts. This work not only provides valuable insights on the response complexity in PDAC, but it also highlights the potential applications (extendable to other tumor types) and clinical translatability of our approach in drug discovery and the emerging era of personalized medicine. |
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Wos |
001118015800001 |
Publication Date |
2023-12-08 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2397-768x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:201455 |
Serial |
9091 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leenaerts, O.; Partoens, B.; Peeters, F.M.; Volodin, A.; van Haesendonck, C. |
Title |
The work function of few-layer graphene |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
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Volume |
29 |
Issue |
3 |
Pages |
035003 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A theoretical and experimental study of the work function of few-layer graphene is reported. The influence of the number of layers on the work function is investigated in the presence of a substrate, a molecular dipole layer, and combinations of the two. The work function of few-layer graphene is almost independent of the number of layers with only a difference between monolayer and multilayer graphene of about 60 meV. In the presence of a charge-donating substrate the charge distribution is found to decay exponentially away from the substrate and this is directly reflected in the work function of few-layer graphene. A dipole layer changes the work function only when placed in between the substrate and few-layer graphene through a change of the charge transfer between the two. |
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Wos |
000425250600002 |
Publication Date |
2016-11-16 |
Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
61 |
Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:164938 |
Serial |
8760 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Legrand, S. |
Title |
Advanced chemical imaging of artworks |
Type |
Doctoral thesis |
Year |
2021 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
315 p. |
Keywords |
Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Last century the field of heritage sciences expanded beyond imagination. The inventions of X-ray radiography and infrared reflectography allowed experts to investigate paintings below the surface as well. More recent developments led to the advent of the field of hyperspectral imaging, to which the advanced chemical imaging methods, used in this thesis work, belong. These techniques not only allow to identify the components present in artworks, but also to visualize their distribution over these objects. The resulting distribution maps permit a broader public to interpret the scientific data and to relate these results with the artwork itself. During this thesis work a range of flat artworks were investigated in a non-destructive manner using mainly two macroscopic imaging techniques: macroscopic X-ray fluorescence scanning and macroscopic Fourier transformed mid-infrared scanning in reflectance mode. The resulting images were sometimes supplemented with microscopic techniques on a minute selection of samples to fully understand the layer build-up, composition and distribution of these materials over the stratigraphy. Illuminated manuscripts pushed the interpretation of the macroscopic imaging techniques: due to the impossibility of sampling, all answers had to be obtained non-destructively. Documenting masterpieces such as the Ghent Altarpiece by means of chemical imaging techniques, helped the restoration team, assisted by the international commission to make the daring decision of manually removing the non-original paint layers. Scanning stained-glass windows allowed experts to document the panels, create situation reports, identify later infills and guide the restoration process in a more efficient manner. By initially applying non-destructive imaging techniques, many of the research/conservation questions could already be answered. Based on the resulting distribution maps, only a very limited amount of sampling was required to obtain a representative set to answer the remaining questions. In most cases the combination of multiple methods was necessary to fully understand the situation. A similar trend could be seen in the research field: the collaboration between divergent disciples was often required in order to explain all observations. In order to completely break through, the scanning speed of these techniques has to increase even more in order to cover an acceptable surface in one workday. Parallel with the operational speed, the (basic) data treatment should also be streamlined more in order to allow a broader user group to access the results. Once these two improvements are carried out, these techniques become accessible to a larger public. |
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UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:176342 |
Serial |
7420 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Legrand, S.; van der Snickt, G.; Cagno, S.; Caen, J.; Janssens, K. |
Title |
MA-XRF imaging as a tool to characterize the 16th century heraldic stained-glass panels in Ghent Saint Bavo Cathedral |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Journal of cultural heritage |
Abbreviated Journal |
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Volume |
40 |
Issue |
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Pages |
163-168 |
Keywords |
A1 Journal article; Art; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
Abstract |
MA-XRF is a novel macroscopic imaging technique originally developed for easel paintings and recently made available to glass conservators. This paper discusses the first real-life contribution of MA-XRF imaging to a conservation intervention of stained-glass panels. The six panels under study belong to the cathedral building since their creation in 1555-1559 AD. MA-XRF appeared an outstanding tool for first-line screening of stained-glass windows, providing readily interpretable information on glass type, coloring and alteration processes. In particular, the chemical imaging technique allowed distinguishing unambiguously the surviving original glass panes from later additions, thereby ensuring a correct historical understanding. From a more practical point of view, the experiments supplied accurate schemes that can be directly incorporated in condition reports and assist designing the ensuing conservation approach. (C0 2019 Elsevier Masson SAS. All rights reserved. |
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Place of Publication |
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Wos |
000491173800017 |
Publication Date |
2019-06-26 |
Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1296-2074 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:167564 |
Serial |
8191 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Legrand, S.; Vanmeert, F.; van der Snickt, G.; Alfeld, M.; de Nolf, W.; Dik, J.; Janssens, K. |
Title |
Examination of historical paintings by state-of-the-art hyperspectral imaging methods : from scanning infra-red spectroscopy to computed X-ray laminography |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Heritage science |
Abbreviated Journal |
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Volume |
2 |
Issue |
|
Pages |
13-11 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The development of advanced methods for non-destructive selective imaging of painted works of art at the macroscopic level based on radiation in the X-ray and infrared range of the electromagnetic spectrum are concisely reviewed. Such methods allow to either record depth-selective, element-selective or species-selective images of entire paintings. Camera-based full field methods (that record the image data in parallel) can be discerned next to scanning methods (that build up distributions in a sequential manner by scanning a beam of radiation over the surface of an artefact). Six methods are discussed: on the one hand, macroscopic X-ray fluorescence and X-ray diffraction imaging and X-ray laminography and on the other hand macroscopic Mid and Near Infrared hyper- and full spectral imaging and Optical Coherence Tomography. These methods can be considered to be improved versions of the well-established imaging methods employed worldwide for examination of paintings, i.e., X-ray radiography and Infrared reflectography. Possibilities and limitations of these new imaging techniques are outlined. |
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Publication Date |
2014-05-30 |
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Edition |
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ISSN |
2050-7445 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:124629 |
Serial |
5619 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
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 |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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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. |
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Abbreviated Series Title |
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Additional Links |
UA library record |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:206132 |
Serial |
9198 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lenaerts, S.; Honoré, M.; Huyberechts, G.; Roggen, J.; Maes, G. |
Title |
In situ infrared and electrical characterization of tin dioxide gas sensors in nitrogen/oxygen mixtures at temperatures up to 720 K |
Type |
A1 Journal article |
Year |
1994 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
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Volume |
19 |
Issue |
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Pages |
478-482 |
Keywords |
A1 Journal article |
Abstract |
FT-IR spectroscopy and impedance measurements of tin dioxide sensor materials at working temperatures up to 450 °C in atmospheres with varying O2/N2 ratio are used as an in situ probe to study the interactions at the surface of the semiconducting oxide. Every diminution in the oxygen content above the sample induces a broad IR absorption band (X-band) between 2300700 cm−1 with a few small peaks in the 1400850 cm−1 region of the spectrum superimposed on it. The X-band results from the enchanced electron concentration in the bulk of the tin dioxide domain. The fine structure is due to the absorption of several kinds of surface oxygen species associated vibration modes. The porous tin dioxide consists of domains were the outward shell is depleted of electrons by the formation of adsorbed O− species on oxygen surface sites, SO(O− species. In our proposed model for the impedance data this gives rise to a parallel RpCp circuit for the domain boundary characteristics and to an Rs parameter for the intradomain resistance. The evolution of these IR and impedance spectroscopic effects with temperature and oxygen content is used to set up, to confirm and refine a physicochemical operation model of tin dioxide gas sensor. This model consists of a sensitizing reaction sequence in the presence of oxygen and a gas-detection reaction sequence when a reducing gas is present. Based on this model, the principal disadvantages of this type of gas sensor become clear. Every factor that influences the concentration of SO(O−) species, causes a conductance modification. If we can control and direct the nature, the number and the arrangement of the tin dioxide domains, a directed development and improvement of the sensor characteristics is possible. |
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Wos |
A1994NN90000040 |
Publication Date |
2002-07-25 |
Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0925-4005 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:82014 |
Serial |
5962 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Lenaerts, S.; Roggen, J.; Maes, G. |
Title |
FT-IR characterization of tin dioxide gas sensor materials under working conditions |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Spectrochimica acta: part A: molecular and biomolecular spectroscopy |
Abbreviated Journal |
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Volume |
51 |
Issue |
5 |
Pages |
883-894 |
Keywords |
A1 Journal article |
Abstract |
In this work self-supporting tin dioxide disks are characterized using FT-IR spectroscopy in the presence of a reducing gas in air, and in different O2/N2 mixtures at temperatures varying from room temperature up to 450°C. Every factor inducing a change in the oxygen content of the gas atmosphere above the tin dioxide, as for instance a temperature change, a surface reaction or adsorption of another species, induces a broad, intense IR absorption band with discrete weak bands superimposed on it. This broad absorption is assigned to the electronic transition from a native donor level, the oxygen vacancy in the bulk of the domain, to the conduction band of the tin dioxide material. For the interpretation of the narrow, superimposed absorptions, two hypotheses remain. The results demonstrate that FT-IR spectroscopy is an extremely suitable technique for the characterization of semiconducting metal oxide sensors, since it allows to follow in situ the processes in the bulk, at the surface and in the surrounding gas atmosphere of the sensor material at working temperature as well as in the presence of reducing gases in air. |
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Wos |
A1995RJ99900014 |
Publication Date |
2003-04-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1386-1425 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:82015 |
Serial |
5954 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leysen, L.; Roekens, E.; Komy, Z.; Van Grieken, R. |
Title |
A study of the weathering of an historic building |
Type |
A1 Journal article |
Year |
1987 |
Publication |
Analytica chimica acta |
Abbreviated Journal |
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Volume |
195 |
Issue |
|
Pages |
247-255 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Various bulk and surface analytical techniques were used to study the chemical deterioration of the 13th-to-15th century limestone cathedral in Mechelen, Belgium. The weathering crust on the walls was found to be rich in sulfate, regardless of the geographic orientation. Nitrate and chloride were only detected in minor amounts in the crust and run-off samples. Attack by gaseous sulfur compounds seems to play a dominant role in the stone deterioration mechanism. Electron microprobe analysis showed predominantly bar-shaped gypsum crystals in the crust, and laser microprobe mass spectrometry showed that carbon seems to be responsible for the blackness of most crust samples. Automated electron microprobe analysis also indicated significant differences in the analytical composition of suspensions in run-off water and in rain-water. |
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Wos |
A1987K019500022 |
Publication Date |
2002-07-25 |
Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2670; 1873-4324 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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no |
Call Number |
UA @ admin @ c:irua:116446 |
Serial |
8608 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leysen, L.; Roekens, E.; Van Grieken, R. |
Title |
Air-pollution-induced chemical decay of a sandy-limestone cathedral in Belgium |
Type |
A1 Journal article |
Year |
1989 |
Publication |
The science of the total environment |
Abbreviated Journal |
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Volume |
78 |
Issue |
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Pages |
263-277 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Different trace- and microanalytical techniques were used in an extensive study to elucidate the chemical deterioration process of the sandy-limestone St Rombouts Cathedral in Mechelen, Belgium. Samples of stones, mortar joints, slates, atmospheric aerosols and gases, total and wet deposition, and water that had run down the cathedral walls, were all thoroughly characterized. At the east side, usually not exposed to precipitation, a 3001000-μm thick outer crust of microcrystalline gypsum was observed, while at the west side, this surface layer was mostly eroded away due to precipitation. At the north and south sides, the crust contains varying amounts of gypsum and calcite. The gypsum is mostly present in a bar-shaped morphology and carbonaceous fly-ash particles were rarely found in the weathering crust. Local stone characteristics seem to be extremely important in relation to the gypsum content of the crust; black samples always have a much higher sulphate content than the corresponding white samples, irrespective of the predominant direction of orientation. The relative contribution of nitrogen- and chlorine-containing pollutants to the total decay process is much smaller than that of sulphur-containing pollutants. Deposition samples collected at the site of the cathedral mostly had a pH of > 5.6, due to the neutralization of the rainwater by alkaline atmospheric constituents. Runoff water and washdown water were enriched in all ions, especially Ca2+ and SO42−, indicating that, indeed, gypsum is the most important weathering product. The suspension in deposition samples and black-well leaching water was highly enriched in silicon-containing particles, while runoff water and white-wall leaching water contained a predominant calcium-rich suspension. |
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Wos |
A1989R806400021 |
Publication Date |
2003-09-12 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0048-9697; 1879-1026 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116649 |
Serial |
7431 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leysen, L.; Roekens, E.; Van Grieken, R. |
Title |
Effecten van luchtverontreiniging op historische gebouwen |
Type |
P3 Proceeding |
Year |
1987 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
P3 Proceeding; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:117518 |
Serial |
7839 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leysen, L.A.; De Waele, J.K.; Roekens, E.J.; Van Grieken, R.E. |
Title |
Electron probe micro-analysis and laser microprobe mass analysis of material, leached from a limestone cathedral |
Type |
A1 Journal article |
Year |
1987 |
Publication |
Scanning microscopy |
Abbreviated Journal |
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Volume |
1 |
Issue |
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Pages |
1617-1630 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Publication Date |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0891-7035 |
ISBN |
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Additional Links |
UA library record |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116794 |
Serial |
7872 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leysen, L.A.; Roekens, E.J.; Storms, H.; Van Grieken, R.E. |
Title |
Classification of suspended particles in deposition samples and run-off water samples from a limestone cathedral |
Type |
A1 Journal article |
Year |
1987 |
Publication |
Atmospheric environment |
Abbreviated Journal |
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Volume |
21 |
Issue |
11 |
Pages |
2425-2433 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In a study on the mechanism of the air-pollution induced deterioration of the limestone St. Rombouts cathedral in Mechelen, Belgium, automated electron-probe X-ray micro-analysis combined with multivariate analysis was used to characterize the suspension particles in run-off water and in local wet and dry deposition samples. Altogether about 10,000 individual particles were sized, analyzed and classified, according to their chemical composition. It was found that the run-off water samples were highly enriched in CaCO3 particles, resulting from the stone-erosion by overflowing rainwater, while the Si-rich group was the most abundant one in the deposition samples. Several other particle types were found. Ion chromatography analysis of the run-off water showed 2001700mg l−1 of sulphate and 20110mg l−1 of nitrate. |
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Publication Date |
2003-08-06 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0004-6981 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116454 |
Serial |
7670 |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leysen, L.A.; Roekens, E.J.; Van Grieken, R.E.; De Geyter, G. |
Title |
Characterization of the weathering crust of various historical buildings in Belgium |
Type |
A1 Journal article |
Year |
1990 |
Publication |
The science of the total environment |
Abbreviated Journal |
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Volume |
90 |
Issue |
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Pages |
117-147 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
A variety of samples, collected from different historical buildings and monuments throughout Belgium, were thoroughly studied, using several trace- and micro-analysis techniques. Thin sections of stones and mortar joints were characterized by means of electron probe X-ray microanalysis (EPXMA). The morphological appearance of the surface weathering crust and the possible presence of non-innate particles in the crust were elucidated using petrographical and electron microscopy. Quantitative characterization of the total chemical composition of the crust surface layer and underlying layer was performed by energy-dispersive X-ray fluorescence, and by ion chromatography and atomic absorption spectrometry for the leachable components. Special attention was also paid to the chemical composition of rain and air at the particular sampling sites. The element distribution in the transition zone between the weathering crust and the original stone material was found to vary greatly amongst the different samples analyzed. Detailed EPXMA measurements on pieces of the weathering crust showed remarkable differences in morphology and composition between the surface and the underlying layer, and provided information about the presence of fly-ash and soil dust particles in the crust. Except for crusts from the city of Brussels, which were all very high in sulphate, the samples appeared to contain very variable sulphate contents; very local micro-climate and environmental conditions at a particular site are more important in determining the weathering condition of the building stones than the local air pollution situation. Bulk analytical characterization further showed, in all the crust samples studied, a very small contribution of nitrogen- and chlorine-containing weathering products, in contrast to sulphur-containing weathering salts. |
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Wos |
A1990CJ43500010 |
Publication Date |
2003-09-12 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0048-9697; 1879-1026 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:116650 |
Serial |
7636 |
Permanent link to this record |
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Author ![sorted by Author field, ascending order (up)](img/sort_asc.gif) |
Leyva Pernia, D.; Cabal Rodríguez, A.E.; Schalm, O.; van Espen, P.; Piñera Hernández, I.; Abreu Alfonso, Y. |
Title |
Study of the main physical processes contributing to image formation in emission radiography using mathematical modeling |
Type |
P3 Proceeding |
Year |
2013 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
P3 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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ISSN |
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ISBN |
978-959-7136-98-9 |
Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:135412 |
Serial |
8607 |
Permanent link to this record |