Records |
Author |
Cosyns, P.; Vanderhoeven, A.; Vynckier, G.; Janssens, K.; Schalm, O.; Vanderlinden, V. |
Title |
Two fragments of mold-blown glass beakers with Greek inscriptions from Tongeren (Belgium) |
Type |
A1 Journal article |
Year |
2005 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of glass studies |
Abbreviated Journal |
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Volume |
47 |
Issue |
|
Pages |
179-183 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
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Publication Date |
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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 |
0075-4250 |
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:56123 |
Serial |
5883 |
Permanent link to this record |
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Author |
Van Oijstaeijen, W.; Van Passel, S.; Cools, J.; Janssens de Bisthoven, L.; Huge, J.; Berihun, D.; Ejigu, N.; Nyssen, J. |
Title |
Farmers' preferences towards water hyacinth control : a contingent valuation study |
Type |
A1 Journal article |
Year |
2020 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal Of Great Lakes Research |
Abbreviated Journal |
J Great Lakes Res |
Volume |
46 |
Issue |
5 |
Pages |
1459-1468 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
Lake Tana is the most important freshwater lake in Ethiopia. Besides pressures on water quality resulting from urbanization and deforestation, the invasion of the exotic water hyacinth (Eichhornia crassipes) poses new threats to the ecosystem. Water hyacinth, endemic to South America, is widely considered as the world's worst aquatic invasive weed. In 2011, the weed appeared on the northern shores of Lake Tana, expanding in south-eastern direction. The lake area affected by water hyacinth was last estimated in 2015 at 34,500 ha, which equals 16% of the total lake surface. In this research, the benefits of water hyacinth control and eradication for the rural population inhabiting the northern and northeastern villages bordering Lake Tana, are investigated. In the area, the population largely depends on farming and fishing. An assessment of the total economic benefit of eradication was conducted. The stakeholder-centered approach led to measuring the willingness to contribute in labor and cash terms. Results showed smallholders in the study are willing to contribute over half-a-million euros annually. Costs of management actions can be weighed to the benefits, where further research is needed on the impact on other stakeholder groups. Moreover, wetland management should advance to explore multiple pathways in an integrated approach: water hyacinth control, water hyacinth utilization and sustainable waste water management. (C) 2020 International Association for Great Lakes Research. Published by Elsevier B.V. All rights reserved. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Wos |
000579717900036 |
Publication Date |
2020-06-27 |
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 |
|
ISSN |
0380-1330 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.2 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 2.2; 2020 IF: 1.958 |
Call Number |
UA @ admin @ c:irua:173644 |
Serial |
6925 |
Permanent link to this record |
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Author |
Esquivel, D.; Ouwehand, J.; Meledina, M.; Turner, S.; Tendeloo, G.V.; Romero-Salguero, F.J.; Clercq, J.D.; Voort, P.V.D. |
Title |
Thiol-ethylene bridged PMO: A high capacity regenerable mercury adsorbent via intrapore mercury thiolate crystal formation |
Type |
A1 Journal article |
Year |
2017 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
339 |
Issue |
339 |
Pages |
368-377 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Highly ordered thiol-ethylene bridged Periodic Mesoporous Organosilicas were synthesized directly from a homemade thiol-functionalized bis-silane precursor. These high surface area materials contain up to 4.3 mmol/g sulfur functions in the walls and can adsorb up to 1183 mg/g mercury ions. Raman spectroscopy reveals the existence of thiol and disulfide moieties. These groups have been evaluated by a combination of Raman spectroscopy, Ellman’s reagent and elemental analysis. The adsorption of mercury ions was evidenced by different techniques, including Raman, XPS and porosimetry, which indicate that thiol groups are highly accessible to mercury. Scanning transmission electron microscopy combined with EDX showed an even homogenous distribution of the sulfur atoms throughout the structure, and have revealed for the first time that a fraction of the adsorbed mercury is forming thiolate nanocrystals in the pores. The adsorbent is highly selective for mercury and can be regenerated and reused multiple times, maintaining its structure and functionalities and showing only a marginal loss of adsorption capacity after several runs. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000407188200040 |
Publication Date |
2017-06-22 |
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 |
|
ISSN |
0304-3894 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
12 |
Open Access |
OpenAccess |
Notes |
D.E. thanks the F.W.O. Flanders (Fund Scientific Research) for a postdoctoral grant (3E10813W). J.O. acknowledges also F.W.O. Flanders, research project G006813N, and the research Board of Ghent University, UGent GOA (Concerted Research Actions) (grant 01G00710) for financial support. F. J. R.-S. acknowledges funding of this research by the Spanish Ministry of Economy and Competitiveness (Project MAT2013-44463-R), Andalusian Regional Government (FQM-346 group), and Feder Funds. The Titan microscope used for this investigation was partially funded by the Hercules foundation of the Flemish government. This work was supported by the Belgian IAP-PAI network. |
Approved |
Most recent IF: 6.065 |
Call Number |
EMAT @ emat @ c:irua:144433 |
Serial |
4624 |
Permanent link to this record |
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Author |
De Decker, J.; Folens, K.; De Clercq, J.; Meledina, M.; Van Tendeloo, G.; Du Laing, G.; Van Der Voort, P. |
Title |
Ship-in-a-bottle CMPO in MIL-101(Cr) for selective uranium recovery from aqueous streams through adsorption |
Type |
A1 Journal article |
Year |
2017 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
335 |
Issue |
|
Pages |
1-9 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Mesoporous MIL-101(Cr) is used as host for a ship-in-a-bottle type adsorbent for selective U(VI) recovery from aqueous environments. The acid-resistant cage-type MOF is built in-situ around N,N-Diisobutyl-2-(octylphenylphosphoryl)acetamide (CMPO), a sterically demanding ligand with high U(VI) affinity. This one-step procedure yields an adsorbent which is an ideal compromise between homogeneous and heterogeneous systems, where the ligand can act freely within the pores of MIL-101, without leaching, while the adsorbent is easy separable and reusable. The adsorbent was characterized by XRD, FTIR spectroscopy, nitrogen adsorption, XRF, ADF-STEM and EDX, to confirm and quantify the successful encapsulation of the CMPO in MIL-101, and the preservation of the host. Adsorption experiments with a central focus on U(VI) recovery were performed. Very high selectivity for U(VI) was observed, while competitive metal adsorption (rare earths, transition metals...) was almost negligible. The adsorption capacity was calculated at 5.32 mg U/g (pH 3) and 27.99 mg U/g (pH 4), by fitting equilibrium data to the Langmuir model. Adsorption kinetics correlated to the pseudo-second-order model, where more than 95% of maximum uptake is achieved within 375 min. The adsorbed U(VI) is easily recovered by desorption in 0.1 M HNO3. Three adsorption/desorption cycles were performed. (C) 2017 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000402948600001 |
Publication Date |
2017-04-09 |
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 |
0304-3894 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
35 |
Open Access |
OpenAccess |
Notes |
; The authors acknowledge the AUGent/UGent for financial support, Grant Number DEF12/AOP/008 fund IV1. ; |
Approved |
Most recent IF: 6.065 |
Call Number |
UA @ lucian @ c:irua:144153 |
Serial |
4685 |
Permanent link to this record |
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Author |
Vanraes, P.; Wardenier, N.; Surmont, P.; Lynen, F.; Nikiforov, A.; Van Hulle, S.W.H.; Leys, C.; Bogaerts, A. |
Title |
Removal of alachlor, diuron and isoproturon in water in a falling film dielectric barrier discharge (DBD) reactor combined with adsorption on activated carbon textile: Reaction mechanisms and oxidation by-products |
Type |
A1 Journal article |
Year |
2018 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
354 |
Issue |
|
Pages |
180-190 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A falling film dielectric barrier discharge (DBD) plasma reactor combined with adsorption on activated carbon textile material was optimized to minimize the formation of hazardous oxidation by-products from the treatment of persistent pesticides (alachlor, diuron and isoproturon) in water. The formation of by-products and the reaction mechanism was investigated by HPLC-TOF-MS. The maximum concentration of each by-product was at least two orders of magnitude below the initial pesticide concentration, during the first 10 min of treatment. After 30 min of treatment, the individual by-product concentrations had decreased to values of at least three orders of magnitude below the initial pesticide concentration. The proposed oxidation pathways revealed five main oxidation steps: dechlorination, dealkylation, hydroxylation, addition of a double-bonded oxygen and nitrification. The latter is one of the main oxidation mechanisms of diuron and isoproturon for air plasma treatment. To our knowledge, this is the first time that the formation of nitrificated intermediates is reported for the plasma treatment of non-phenolic compounds. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000437814600021 |
Publication Date |
2018-05-03 |
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 |
|
ISSN |
0304-3894 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
4 |
Open Access |
Not_Open_Access: Available from 04.05.2020
|
Notes |
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors would like to thank Carbon Cloth Division for Zorflex® samples and personally thank Jack Taylor for fruitful discussion of active carbon water treatment processes |
Approved |
Most recent IF: 6.065 |
Call Number |
PLASMANT @ plasmant @c:irua:152179 |
Serial |
4989 |
Permanent link to this record |
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Author |
Leus, K.; Folens, K.; Nicomel, N.R.; Perez, J.P.H.; Filippousi, M.; Meledina, M.; Dirtu, M.M.; Turner, S.; Van Tendeloo, G.; Garcia, Y.; Du Laing, G.; Van Der Voort, P. |
Title |
Removal of arsenic and mercury species from water by covalent triazine framework encapsulated \gamma-Fe2O3 nanoparticles |
Type |
A1 Journal article |
Year |
2018 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
353 |
Issue |
353 |
Pages |
312-319 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The covalent triazine framework, CTF-1, served as host material for the in situ synthesis of Fe2O3 nanoparticles. The composite material consisted of 20 +/- 2 m% iron, mainly in gamma-Fe2O3 phase. The resulting gamma-Fe2O3@CTF-1 was examined for the adsorption of As-III, As-V and H-II from synthetic solutions and real surface-, ground- and wastewater. The material shows excellent removal efficiencies, independent from the presence of Ca2+, Mg2+ or natural organic matter and only limited dependency on the presence of phosphate ions. Its adsorption capacity towards arsenite (198.0 mg g(-1)), arsenate (102.3 mg g(-1)) and divalent mercury (165.8 mg g(-1)) belongs amongst the best-known adsorbents, including many other iron-based materials. Regeneration of the adsorbent can be achieved for use over multiple cycles without a decrease in performance by elution at 70 degrees C with 0.1 M NaOH, followed by a stirring step in a 5 m% H2O2 solution for As or 0.1 M thiourea and 0.001 M HCl for Hg. In highly contaminated water (100 mu gL(-1)), the adsorbent polishes the water quality to well below the current WHO limits. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000438002800035 |
Publication Date |
2018-04-16 |
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 |
|
ISSN |
0304-3894 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
22 |
Open Access |
OpenAccess |
Notes |
; Karen Leus acknowledges financial support from Ghent University. Nina Ricci Nicomel and Jeffrey Paulo H. Perez thank the funding of the VLIR-UOS. Marinela M. Dirtu acknowledges F.R.S.-FNRS for a Charge de recherches position. Stuart Turner gratefully acknowledges the FWO Vlaanderen for a post-doctoral scholarship. The Titan microscope used for this investigation was partially funded by the Hercules foundation of the Flemish government. This work was supported by the Belgian IAP-PAI network. ; |
Approved |
Most recent IF: 6.065 |
Call Number |
UA @ lucian @ c:irua:152430 |
Serial |
5124 |
Permanent link to this record |
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Author |
Wardenier, N.; Vanraes, P.; Nikiforov, A.; Van Hulle, S.W.H.; Leys, C. |
Title |
Removal of micropollutants from water in a continuous-flow electrical discharge reactor |
Type |
A1 Journal article |
Year |
2019 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
362 |
Issue |
362 |
Pages |
238-245 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The emergence of micropollutants into our aquatic resources is regarded as an issue of increasing environmental concern. To protect the aquatic environment against further contamination with micropollutants, treatment with advanced oxidation processes (AOPs) is put forward as a promising technique. In this work, an innovative AOP based on electrical discharges in a continuous-flow pulsed dielectric barrier discharge (DBD) reactor with falling water film over activated carbon textile is examined for its potential application in water treatment. The effect of various operational parameters including feed gas type, gas flow rate, water flow rate and power on removal and energy efficiency has been studied. To this end, a synthetic micropollutant mixture containing five pesticides (atrazine, alachlor, diuron, dichlorvos and pentachlorophenol), two pharmaceuticals (carbamazepine and 1,7-alpha-ethinylestradiol), and 1 plasticizer (bisphenol A) is used. While working under optimal conditions, energy consumption was situated in the range 2.42-4.25 kW h/m(3), which is about two times lower than the economically viable energy cost of AOPs (5 kW h/m(3)). Hence, the application of non-thermal plasma could be regarded as a promising alternative AOP for (industrial) wastewater remediation. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000449127500027 |
Publication Date |
2018-08-30 |
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 |
0304-3894 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
13 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 6.065 |
Call Number |
UA @ admin @ c:irua:155358 |
Serial |
5279 |
Permanent link to this record |
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Author |
Patiño, Y.; Pilehvar, S.; Díaz, E.; Ordóñez, S.; De Wael, K. |
Title |
Electrochemical reduction of nalidixic acid at glassy carbon electrodemodified with multi-walled carbon nanotubes |
Type |
A1 Journal article |
Year |
2017 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
323 |
Issue |
B |
Pages |
621-631 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The aqueous phase electrochemical degradation of nalidixic acid (NAL) is studied in this work, using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) as instrumental techniques. The promotional effect of multi-walled carbon nanotubes (MWCNT) on the the performance of glassy carbon electrodes is demonstrated, being observed that these materials catalyze the NAL reduction. The effect of surface functional groups on MWCNT −MWCNT-COOH and MWCNT-NH2was also studied. The modification of glassy carbon electrode (GCE) with MWCNT leads to an improved performance for NAL reduction following the order of MWCNT > MWCNT-NH2 > MWCNT-COOH. The best behavior at MWCNT-GCE is mainly due to both the increased electrode active area and the enhanced MWCNT adsorption properties. The NAL degradation was carried out under optimal conditions (pH = 5.0, deposition time = 20 s and volume of MWCNT = 10 μL) using MWCNT-GCE obtaining an irreversible reduction of NAL to less toxic products. Paramaters as the number of DPV cycles and the volume/area (V/A) ratio were optimized for maximize pollutant degradation. It was observed that after 15 DPV scans and V/A = 8, a complete reduction was obtained, obtaining two sub-products identified by liquid chromatography-mass spectrometry (LCMS). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000390513700004 |
Publication Date |
2016-10-16 |
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 |
0304-3894 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the Spanish Government (contract CTQ2011-29272-C04-02) and by the Government of the Principality of Asturias (contract FC-15-GRUPIN14-078). Y. Patifio thanks the Government of the Principality of Asturias for a Ph.D. fellowship (Severo Ochoa Program). S.P. and K.D.W. are thankful to UA for DOCPRO financial support. ; |
Approved |
Most recent IF: 6.065 |
Call Number |
UA @ admin @ c:irua:136108 |
Serial |
5594 |
Permanent link to this record |
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Author |
Pei, Z.-G.; Shan, X.-Q.; Zhang, S.-Z.; Kong, J.-J.; Wen, B.; Zhang, J.; Zheng, L.-R.; Xie, Y.-N.; Janssens, K. |
Title |
Insight to ternary complexes of co-adsorption of norfloxacin and Cu(II) onto montmorillonite at different pH using EXAFS |
Type |
A1 Journal article |
Year |
2011 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
J Hazard Mater |
Volume |
186 |
Issue |
1 |
Pages |
842-848 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Co-adsorption of norfloxacin (Nor) and Cu(II) on montmorillonite at pH 4.5, 7.0 and 9.0 was studied by integrated batch adsorption experiments and extended X-ray absorption fine structure (EXAFS) spectroscopy. Under such pH conditions the dominant species of Nor are cation (Nor+), zwitterion (Nor±), and anion (Nor−), respectively. Results indicated that Nor sorption decreased with an increase of solution pH. The presence of Cu(II) slightly suppressed the Nor+ sorption at pH 4.5, while increased Nor± and Nor−sorption on montmorillonite at pH 7.0 and 9.0, respectively. In contrast, Nor increased Cu(II) adsorption at pH 4.5, but had little effect on the adsorption of Cu(II) on montmorillonite at pH 7.0 and 9.0. Spectroscopic results showed that, at pH 4.5, Nor+ was sorbed on montmorillonite by the formation of outer-sphere montmorilloniteNorCu(II) ternary surface complex. At pH 7.0, montmorilloniteNorCu(II) and montmorilloniteCu(II)Nor ternary surface complexes co-exist. At pH 9.0, montmorilloniteCu(II)Nor ternary surface complex was likely formed, which was different to Cu(II)(Nor)2 precipitate of the solution. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000288102400107 |
Publication Date |
2010-11-26 |
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 |
0304-3894 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.065 |
Times cited |
25 |
Open Access |
|
Notes |
; This work was funded by the National Natural Science Foundation of China (grant numbers: 41071308, 20707037, 20737003 and 20877087) and the Youth Fund of State Key Laboratory of Environmental Chemistry and Ecotoxicology QN2009-07. ; |
Approved |
Most recent IF: 6.065; 2011 IF: 4.173 |
Call Number |
UA @ admin @ c:irua:88786 |
Serial |
5664 |
Permanent link to this record |
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Author |
Damla, N.; Čevik, U.; Kobya, A.I.; Celik, A.; Van Grieken, R.; Kobya, Y. |
Title |
Characterization of gas concrete materials used in buildings of Turkey |
Type |
A1 Journal article |
Year |
2009 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
|
Volume |
168 |
Issue |
2/3 |
Pages |
681-687 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The activity concentration of 226Ra, 232Th and 40K in gas concrete samples collected from different suppliers and some provinces in Turkey were measured using gamma-ray spectrometry. Knowledge of radioactivity in gas concrete used in building materials enables one to assess any possible radiological risks to human health. The mean activity concentrations observed in the gas concrete samples were 82.0, 28.2 and 383.9 Bq kg−1 for 226Ra, 232Th and 40K, respectively. The radium equivalent activity, external and internal hazard indices as well as terrestrial absorbed dose and annual effective dose rate was calculated. The results indicate that the radium equivalent activity values of gas concrete samples are lower than the limit of 370 Bq kg−1, equivalent to a gamma-dose of 1.5 mSv y−1. Moreover, mass attenuation coefficients were measured in some gas concrete samples. It was found that the mass attenuation coefficients decreased with increasing photon energies. Also, chemical compositions and structural analysis (XRD and SEM) of the gas concrete samples were investigated. |
Address |
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Corporate Author |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000268200700014 |
Publication Date |
2009-02-26 |
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 |
0304-3894 |
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:77256 |
Serial |
7621 |
Permanent link to this record |
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Author |
Stefaniak, E.A.; Alsecz, A.; Frost, R.; Máthé, Z.; Sajó, I.E.; Török, S.; Worobiec, A.; Van Grieken, R. |
Title |
Combined SEM/EDX and micro-Raman spectroscopy analysis of uranium minerals from a former uranium mine |
Type |
A1 Journal article |
Year |
2009 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
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Volume |
168 |
Issue |
1 |
Pages |
416-423 |
Keywords |
A1 Journal article; Laboratory Experimental Medicine and Pediatrics (LEMP); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Samples of the secondary uranium minerals collected in the abandoned uranium mine at Pecs (Hungary) were investigated by two micro-techniques: scanning electron microscopy (SEM/EDX) and micro-Raman spectroscopy (MRS). They were applied to locate U-rich particles and identify the chemical form and oxidation state of the uranium compounds. The most abundant mineral was a K and/or Na uranyl sulphate (zippeite group). U(VI) was also present in the form showing intensive Raman scattering at 860 cm−1 which can be attributed to uranium trioxide. This research has shown the successful application of micro-Raman spectroscopy for the identification of uranyl mineral species on the level of individual particles. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000267567600060 |
Publication Date |
2009-02-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3894 |
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:77032 |
Serial |
7681 |
Permanent link to this record |
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|
|
Author |
Velimirovic, M.; Carniato, L.; Simons, Q.; Schoups, G.; Seuntjens, P.; Bastiaens, L. |
Title |
Corrosion rate estimations of microscale zerovalent iron particles via direct hydrogen production measurements |
Type |
A1 Journal article |
Year |
2014 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
|
Volume |
270 |
Issue |
|
Pages |
18-26 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
In this study, the aging behavior of microscale zerovalent iron (mZVI) particles was investigated by quantifying the hydrogen gas generated by anaerobic mZVI corrosion in batch degradation experiments. Granular iron and nanoscale zerovalent iron (nZVI) particles were included in this study as controls. Firstly, experiments in liquid medium (without aquifer material) were performed and revealed that mZV1 particles have approximately a 10-30 times lower corrosion rate than nZVI particles. A good correlation was found between surface area normalized corrosion rate (R-SA) and reaction rate constants (K-SA) of PCE, TCE, cDCE and 1,1,1-TCA. Generally, particles with higher degradation rates also have faster corrosion rates, but exceptions do exists. In a second phase, the hydrogen evolution was also monitored during batch tests in the presence of aquifer material and real groundwater. A 4-9 times higher corrosion rate of mZV1 particles was observed under the natural environment in comparison with the aquifer free artificial condition, which can be attributed to the low pH of the aquifer and its buffer capacity. A corrosion model was calibrated on the batch experiments to take into account the inhibitory effects of the corrosion products (dissolved iron, hydrogen and OH-) on the iron corrosion rate. (C) 2014 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000335109200003 |
Publication Date |
2014-02-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3894 |
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:117179 |
Serial |
7738 |
Permanent link to this record |
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|
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Author |
Celik, N.; Čevik, U.; Celik, A.; Koz, B. |
Title |
Natural and artificial radioactivity measurements in Eastern Black Sea region of Turkey |
Type |
A1 Journal article |
Year |
2009 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
|
Volume |
162 |
Issue |
1 |
Pages |
146-153 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In the present work, naturally occurring radionuclides of (226)Ra, (232)Th and (40)K were measured in soil samples collected from the Eastern Black Sea region of Turkey. It was found that the activity concentrations ranged from 12 to 120 Bq kg(-1) for (226)Ra, from 13 to 121 Bq kg(-1) for (232)Th and from 204 to 1295 Bq kg(-1) for (40)K. Besides naturally occurring radionuclides, (137)Cs activity concentration was measured in soil, lichen and moss samples and it was found that (137)Cs activity concentration ranged from 27 to 775 Bq kg(-1) with for soil, from 29 to 879 Bq kg(-1) for lichen and from 67 to 1396 Bq kg(-1) for moss samples. Annual effective doses due to the naturally occurring radionuclides and (137)CS were estimated. Ecological half-lives of (137)CS in lichen and moss species were estimated. The decrease of the activity concentrations in the present measurements (2007) relative to those in 1993 indicated ecological half-lives between 1.36 and 2.96 years for lichen and between 1.35 and 2.85 years for moss species. (C) 2008 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000263149400019 |
Publication Date |
2008-05-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3894 |
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:94562 |
Serial |
8296 |
Permanent link to this record |
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|
|
Author |
Damla, N.; Čevik, U.; Kobya, A.I.; Celik, A.; Celik, N.; Van Grieken, R. |
Title |
Radiation dose estimation and mass attenuation coefficients of cement samples used in Turkey |
Type |
A1 Journal article |
Year |
2010 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
|
Volume |
176 |
Issue |
1/3 |
Pages |
644-649 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Different cement samples commonly used in building construction in Turkey have been analyzed for natural radioactivity using gamma-ray spectrometry. The mean activity concentrations observed in the cement samples were 52, 40 and 324 Bq kg−1 for 226Ra, 232Th and 40K, respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries and world average limits. The radiological hazard parameters such as radium equivalent activities (Raeq), gamma index (Iγ) and alpha index (Iα) indices as well as terrestrial absorbed dose and annual effective dose rate were calculated and compared with the international data. The Raeq values of cement are lower than the limit of 370 Bq kg−1, equivalent to a gamma dose of 1.5 mSv y−1. Moreover, the mass attenuation coefficients were determined experimentally and calculated theoretically using XCOM in some cement samples. Also, chemical compositions analyses of the cement samples were investigated. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000274839700087 |
Publication Date |
2009-11-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3894 |
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:80671 |
Serial |
8448 |
Permanent link to this record |
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|
|
Author |
Alvarado-Alvarado, A.A.; Smets, W.; Irga, P.; Denys, S. |
Title |
Engineering green wall botanical biofiltration to abate indoor volatile organic compounds : a review on mechanisms, phyllosphere bioaugmentation, and modeling |
Type |
A1 Journal article |
Year |
2024 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hazardous materials |
Abbreviated Journal |
|
Volume |
465 |
Issue |
|
Pages |
133491-16 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Indoor air pollution affects the global population, especially in developed countries where people spend around 90% of their time indoors. The recent pandemic exacerbated the exposure by relying on indoor spaces and a teleworking lifestyle. VOCs are a group of indoor air pollutants with harmful effects on human health at low concentrations. It is widespread that plants can remove indoor VOCs. To this day, research has combined principles of phytoremediation, biofiltration, and bioremediation into a holistic and sustainable technology called botanical biofiltration. Overall, it is sustained that its main advantage is the capacity to break down and biodegrade pollutants using low energy input. This differs from traditional systems that transfer VOCs to another phase. Furthermore, it offers additional benefits like decreased indoor air health costs, enhanced work productivity, and well-being. However, many disparities exist within the field regarding the role of plants, substrate, and phyllosphere bacteria. Yet their role has been theorized; its stability is poorly known for an engineering approach. Previous research has not addressed the bioaugmentation of the phyllosphere to increase the performance, which could boost the system. Moreover, most experiments have studied passive potted plant systems at a lab scale using small chambers, making it difficult to extrapolate findings into tangible parameters to engineer the technology. Active systems are believed to be more efficient yet require more maintenance and knowledge expertise; besides, the impact of the active flow on the long term is not fully understood. Besides, modeling the system has been oversimplified, limiting the understanding and optimization. This review sheds light on the field’s gains and gaps, like concepts, experiments, and modeling. We believe that embracing a multidisciplinary approach encompassing experiments, multiphysics modeling, microbial community analysis, and coworking with the indoor air sector will enable the optimization of the technology and facilitate its adoption. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Wos |
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Publication Date |
2024-01-11 |
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 |
|
ISSN |
0304-3894 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
13.6 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 13.6; 2024 IF: 6.065 |
Call Number |
UA @ admin @ c:irua:202311 |
Serial |
9030 |
Permanent link to this record |
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Author |
De Schepper, V.C.J.; Holvoet, K.M.A.; Benedetti, L.; Seuntjens, P.; Vanrolleghem, P.A. |
Title |
Extension of the river water quality model no. 1 with the fate of pesticides |
Type |
A1 Journal article |
Year |
2012 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hydroinformatics |
Abbreviated Journal |
|
Volume |
14 |
Issue |
1 |
Pages |
48-64 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The existing River Water Quality Model No. 1 (RWQM1) was extended with processes determining the fate of non-volatile pesticides in the water phase and sediments. The exchange of pesticides between the water column and the sediment is described by three transport processes: diffusion, sedimentation and resuspension. Burial of sediments is also included. The modified model was used to simulate the concentrations of diuron and chloridazon in the river Nil. A good agreement was found between the simulated pesticide concentrations and measured values resulting from a four-month intensive monitoring campaign. The simulation results indicate that pesticide concentrations in the bulk water are not sensitive to the selected biochemical model parameters. it seems that these concentrations are mainly determined by the imposed upstream concentrations, run-off and direct losses. The high concentrations in the bulk water were not observed in the sediment pore water due to a limited exchange between the water column and the sediment. According to a sensitivity analysis, the observed pesticide concentrations are highly sensitive to the diffusion and sorption coefficients. Therefore, model users should determine these parameters with accuracy in order to reduce the degree of uncertainty in their results. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000298618300004 |
Publication Date |
2011-10-25 |
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 |
|
ISSN |
1464-7141 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
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:96257 |
Serial |
7954 |
Permanent link to this record |
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Author |
Van Hoey, S.; Nopens, I.; van der Kwast, J.; Seuntjens, P. |
Title |
Dynamic identifiability analysis-based model structure evaluation considering rating curve uncertainty |
Type |
A1 Journal article |
Year |
2015 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hydrologic engineering |
Abbreviated Journal |
|
Volume |
20 |
Issue |
5 |
Pages |
04014072 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
When applying hydrological models, different sources of uncertainty are present, and evaluations of model performances should take these into account to assess model outcomes correctly. Furthermore, uncertainty in the discharge observations complicates the model identification, both in terms of model structure and parameterization. In this paper, the authors compare two different lumped model structures (PDM and NAM) considering uncertainty coming from the rating curve. Limits of acceptability for the model simulations were determined based on derived uncertainty bounds of the discharge observations. The authors applied the DYNamic Identifiability Approach (DYNIA) to identify structural failure of both models and to evaluate the configuration of their structures. In general, similar model performances are observed. However, the model structures tend to behave differently in the course of time, as revealed by the DYNIA approach. Based on the analyses performed, the probability based soil storage representation of the PDM model outperforms the NAM structure. The incorporation of the observation error did not prevent the DYNIA analysis to identify potential model structural deficiencies that are limiting the representation of the seasonal variation, primarily indicated by shifting regions of parameter identifiability. As such, the proposed approach is able to indicate where deficiencies are found and model improvement is needed. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000353995400002 |
Publication Date |
2014-03-06 |
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 |
|
ISSN |
1084-0699 |
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:126056 |
Serial |
7829 |
Permanent link to this record |
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Author |
Annys, S.; Adgo, E.; Ghebreyohannes, T.; Van Passel, S.; Dessein, J.; Nyssen, J. |
Title |
Impacts of the hydropower-controlled Tana-Beles interbasin water transfer on downstream rural livelihoods (northwest Ethiopia) |
Type |
A1 Journal article |
Year |
2019 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal Of Hydrology |
Abbreviated Journal |
J Hydrol |
Volume |
569 |
Issue |
569 |
Pages |
436-448 |
Keywords |
A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
Despite public awareness of unintended impacts (1980s) and well-developed international standards (2000s), downstream impacts of large hydropower projects still very often are not properly assessed. Impacts of (hydropower-regulated) interbasin water transfers (IBWTs) are considered self-evidently positive, although they can have far-reaching consequences for hydrogeomorphological systems and consequently river-dependent communities. In this study, the downstream direct and indirect impacts of the Ethiopian hydropower-regulated Tana-Beles IBWT are evaluated in an interdisciplinary way. The components of the framework of rural livelihoods are considered and changing contexts, resources availabilities and livelihood strategies are analysed. Mixed methods are applied, combining hydrogeomorphological field observations, GIS analyses, scientific literature, policy documents, and semi-structured interviews with local people and local to federal authorities. Results show that the IBWT drastically increased the Beles rivers discharge (with an average release of +92 m3 s−1 at the outlet; *2 in rainy season and *12 in dry season 100 km downstream of the water release) and introduced dangerous situations for local communities (over 250 people drowned in the river). River bank erosion resulted in the uncompensated loss of farmland (163 ha) and the establishment of large-scale commercial farms increased the pressure on land and led to the impoverishment of displaced communities (4310 households). The project was implemented top-down, without any transparency, benefit sharing or compensation for external costs. This stresses the importance of downstream interdisciplinary impact assessments and highlights the need for decent in-depth ex post-analyses of hydropower projects. Environmental impact assessments should be taken seriously and cannot be considered a formality. In Ethiopia and in many developing countries, the hydropower industry is booming. Although dams and IBWTs can be the best solution for water-related problems in specific contexts, national development goals (such as the expansion of the electricity network) should not be at the expense of rural livelihoods. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000457952900032 |
Publication Date |
2018-12-15 |
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 |
|
Edition |
|
ISSN |
0022-1694 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.483 |
Times cited |
2 |
Open Access |
|
Notes |
; This study was funded by the Flemish Research Foundation (FWO, Belgium), through project No. G022217N and a specific travel grant for a long stay abroad (No. V445417N). We acknowledge the cooperation with the Bahir Dar University VLIR-UOS IUC programme. All support given by Bahir Dar University has been greatly appreciated and many thanks go to Yonnas Shawul and Deribew Fenetie, for assisting and translating in the field. Staff of various ranks in administrative offices are thanked for their cooperation and mostly openness during interviews. Special thanks go to the local farmers and other rural dwellers, for their cooperation and contribution to this research. We thank the two anonymous reviewers for their constructive comments. ; |
Approved |
Most recent IF: 3.483 |
Call Number |
UA @ admin @ c:irua:156935 |
Serial |
6215 |
Permanent link to this record |
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Author |
Van Hoey, S.; Seuntjens, P.; van der Kwast, J.; Nopens, I. |
Title |
A qualitative model structure sensitivity analysis method to support model selection |
Type |
A1 Journal article |
Year |
2014 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hydrology |
Abbreviated Journal |
|
Volume |
519 |
Issue |
D |
Pages |
3426-3435 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The selection and identification of a suitable hydrological model structure is a more challenging task than fitting parameters of a fixed model structure to reproduce a measured hydrograph. The suitable model structure is highly dependent on various criteria, i.e. the modeling objective, the characteristics and the scale of the system under investigation and the available data. Flexible environments for model building are available, but need to be assisted by proper diagnostic tools for model structure selection. This paper introduces a qualitative method for model component sensitivity analysis. Traditionally, model sensitivity is evaluated for model parameters. In this paper, the concept is translated into an evaluation of model structure sensitivity. Similarly to the one-factor-at-a-time (OAT) methods for parameter sensitivity, this method varies the model structure components one at a time and evaluates the change in sensitivity towards the output variables. As such, the effect of model component variations can be evaluated towards different objective functions or output variables. The methodology is presented for a simple lumped hydrological model environment, introducing different possible model building variations. By comparing the effect of changes in model structure for different model objectives, model selection can be better evaluated. Based on the presented component sensitivity analysis of a case study, some suggestions with regard to model selection are formulated for the system under study: (1) a non-linear storage component is recommended, since it ensures more sensitive (identifiable) parameters for this component and less parameter interaction; (2) interflow is mainly important for the low flow criteria; (3) excess infiltration process is most influencing when focussing on the lower flows; (4) a more simple routing component is advisable; and (5) baseflow parameters have in general low sensitivity values, except for the low flow criteria. (C) 2014 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000347589600057 |
Publication Date |
2014-10-08 |
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 |
|
ISSN |
0022-1694 |
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:123809 |
Serial |
7395 |
Permanent link to this record |
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Author |
Rezaei, M.; Seuntjens, P.; Shahidi, R.; Joris, I.; Boenne, W.; Al-Barri, B.; Cornelis, W. |
Title |
The relevance of in-situ and laboratory characterization of sandy soil hydraulic properties for soil water simulations |
Type |
A1 Journal article |
Year |
2016 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of hydrology |
Abbreviated Journal |
|
Volume |
534 |
Issue |
|
Pages |
251-265 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Field water flow processes can be precisely delineated with proper sets of soil hydraulic properties derived from in situ and/or laboratory experiments. In this study we analyzed and compared soil hydraulic properties obtained by traditional laboratory experiments and inverse optimization tension infiltrometer data along the vertical direction within two typical Podzol profiles with sand texture in a potato field. The main goal was to identify proper sets of hydraulic parameters and to evaluate their relevance on hydrological model performance for irrigation management purposes. Tension disc infiltration experiments were carried out at four and five different depths for both profiles at consecutive negative pressure heads of 12, 6, 3 and 0.1 cm. At the same locations and depths undisturbed samples were taken to determine Mualem-van Genuchten (MVG) hydraulic parameters (theta(r), residual water content, theta(s), saturated water content, alpha and n, shape parameters and K-ls, saturated hydraulic conductivity) in the laboratory. Results demonstrated horizontal differences and vertical variability of hydraulic properties. The tension disc infiltration data fitted well in inverse modeling using Hydrus 2D/3D in combination with final water content at the end of the experiment, theta(f). Four MVG parameters (theta(s), alpha, n and field saturated hydraulic conductivity K-fs) were estimated (theta(r) set to zero), with estimated K-ls and alpha values being relatively similar to values from Wooding's solution which used as initial value and estimated theta(s) corresponded to (effective) field saturated water content, theta(f). The laboratory measurement of K-ls yielded 2-30 times higher values than the field method K-fs from top to subsoil layers, while there was a significant correlation between both K-s values (r = 0.75). We found significant differences of MVG parameters theta(s), n and alpha values between laboratory and field measurements, but again a significant correlation was observed between laboratory and field MVG parameters namely K-s, n, theta(s) (r >= 0.59). Assessment of the parameter relevance in 1-D model simulations, illustrated that the model over predicted and under predicted top soil-water content using laboratory and field experiments data sets respectively. The field MVG parameter data set resulted in better agreement to observed soil-water content as compared to the laboratory data set at nodes 10 and 20 cm. However, better simulation results were achieved using the laboratory data set at 30-60 cm depths. Results of our study do not confirm whether laboratory or field experiments data sets are most appropriate to predict soil water fluctuations in a complete soil profile, while field experiments are preferred in many studies. (C) 2016 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000371940900022 |
Publication Date |
2016-01-11 |
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 |
|
ISSN |
0022-1694 |
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:133161 |
Serial |
8657 |
Permanent link to this record |
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Author |
van Renterghem, W.; Schryvers, D.; van Landuyt, J.; van Roost, C.; de Keyzer, R. |
Title |
The influence of crystal thickness on the image tone |
Type |
A1 Journal article |
Year |
2003 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of imaging science |
Abbreviated Journal |
J Imaging Sci Techn |
Volume |
47 |
Issue |
2 |
Pages |
133-138 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
It is known that the neutral image tone of a developed photographic film becomes brownish when the thickness of the original silver halide tabular crystals is reduced. We investigate by electron microscopy to what extent the silver filament structure has changed and how it induces the shift in image tone. Therefore, two samples of AgBr {111} tabular crystals with average thicknesses of 160 nm and 90 nm respectively, are compared. It is shown that the dimensions and defect structure of the filaments are comparable, but that the 90 nm crystals result in a more widely spaced structure, which explains the shift in image tone on a qualitative level. The influence of the addition of an image toner, i.e., phenylmercaptotetrazole, on the filament structure is also investigated. An even more open filament structure of longer, but smaller filaments was observed. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Springfield, Va |
Editor |
|
Language |
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Wos |
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Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
8750-9237; 1062-3701 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.348 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:48384 |
Serial |
1619 |
Permanent link to this record |
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|
|
Author |
Charlier, E.; van Doorselaer, M.; Gijbels, R.; de Keyzer, R.; Geuens, I. |
Title |
Unveiling the composition of sulphur sensitization specks by their interactions with TAI |
Type |
A1 Journal article |
Year |
2000 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal Of Imaging Science And Technology |
Abbreviated Journal |
J Imaging Sci Techn |
Volume |
44 |
Issue |
3 |
Pages |
235-241 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A two-step process for the formation of sensitivity centers different from earlier described two-step processes was found for sulfur sensitized emulsions. After deposition of sulfur in the first step, it was found that the second step does not consist of rearrangement of sulfur over the surface, but of the supply of silver interstitial ions towards the deposited sulfur clusters. The two processes could be separated by adsorbing and desorbing TAI (4-hydroxy-1, 3,3a, 7-tetraazaindene) at/from the silver halide surface. When 1.5 mmol TAI/mol Ag is added before the sulfur reaction, the silver interstitials are immobilized but sulfur still can be deposited at the same level. By lowering the pH to 2.50 after this sulfur reaction, TAI is desorbed from the surface and the released interstitials then cause a restoration of the properties of a sulfur system without TAI. These effects could be demonstrated via diffuse reflectance spectroscopy (DRS), sensitometry and dielectric loss measurements. We could also confirm the isolation of silver sulfide clusters by TAI from other chemicals in the solution, by adsorption of TAI on the clusters. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Springfield, Va |
Editor |
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Language |
|
Wos |
000087651100010 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1062-3701 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.348 |
Times cited |
16 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.348; 2000 IF: NA |
Call Number |
UA @ lucian @ c:irua:34075 |
Serial |
3820 |
Permanent link to this record |
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|
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Author |
Cuypers, B.; Vermeylen, S.; Hammerschmid, D.; Trashin, S.; Rahemi, V.; Konijnenberg, A.; De Schutter, A.; Cheng, C.-H.C.; Giordano, D.; Verde, C.; De Wael, K.; Sobott, F.; Dewilde, S.; Van Doorslaer, S. |
Title |
Antarctic fish versus human cytoglobins : the same but yet so different |
Type |
A1 Journal article |
Year |
2017 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of inorganic biochemistry |
Abbreviated Journal |
J Inorg Biochem |
Volume |
173 |
Issue |
|
Pages |
66-78 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The cytoglobins of the Antarctic fish Chaenocephalus aceratus and Dissostichus mawsoni have many features in common with human cytoglobin. These cytoglobins are heme proteins in which the ferric and ferrous forms have a characteristic hexacoordination of the heme iron, i.e. axial ligation of two endogenous histidine residues, as confirmed by electron paramagnetic resonance, resonance Raman and optical absorption spectroscopy. The combined spectroscopic analysis revealed only small variations in the heme-pocket structure, in line with the small variations observed for the redox potential. Nevertheless, some striking differences were also discovered. Resonance Raman spectroscopy showed that the stabilization of an exogenous heme ligand, such as CO, occurs differently in human cytoglobin in comparison with Antarctic fish cytoglobins. Furthermore, while it has been extensively reported that human cytoglobin is essentially monomeric and can form an intramolecular disulfide bridge that can influence the ligand binding kinetics, 3D modeling of the Antarctic fish cytoglobins indicates that the cysteine residues are too far apart to form such an intramolecular bridge. Moreover, gel filtration and mass spectrometry reveal the occurrence of non-covalent multimers (up to pentamers) in the Antarctic fish cytoglobins that are formed at low concentrations. Stabilization of these oligomers by disulfide-bridge formation is possible, but not essential. If intermolecular disulfide bridges are formed, they influence the heme-pocket structure, as is shown by EPR measurements. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000405159600007 |
Publication Date |
2017-04-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0162-0134 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.348 |
Times cited |
7 |
Open Access |
|
Notes |
; The authors acknowledge the support of the University of Antwerp GOA-BOF funding (28312), FWO funding (G.0687.13) and the Hercules foundation for funding of the Synapt G2 instrument. This study was carried out in the framework of the SCAR program “Antarctic Thresholds – Ecosystem Resilience and Adaptation” (AnT-ERA). It was financially supported by the Italian National Program for Antarctic Research (PNRA). Research of A. De Schutter is funded by a PhD grant of the Agency for Innovation by Science and Technology (121339) (IWT, Belgium). C-H C. Cheng acknowledges funding support from US National Science Foundation Polar Programs (ANT-1142158). ; |
Approved |
Most recent IF: 3.348 |
Call Number |
UA @ admin @ c:irua:144826 |
Serial |
5474 |
Permanent link to this record |
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Author |
Gebrehiwot, N.T.; Azadi, H.; Taheri, F.; Van Passel, S. |
Title |
How participation in vegetables market affects livelihoods : empirical evidence from Northern Ethiopia |
Type |
A1 Journal article |
Year |
2018 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of international food and agribusiness marketing |
Abbreviated Journal |
|
Volume |
30 |
Issue |
2 |
Pages |
107-131 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
Vegetable farmers face a number of challenges in marketing. Having first-hand information about vegetable marketing is essential to devise appropriate strategies aimed at enhancing the value of the vegetable chain. It was in line with this view that the study was conducted to characterize vegetable markets in Northern Ethiopia. In an effort to identify the factors influencing vegetable marketing among farmers, data were collected from 283 farm households who were selected using stratified random sampling. Furthermore, the data were triangulated through focus group discussion (FGD) and key informant interviews. Descriptive statistics and the binary logistic regression model were used to identify the variables and test the probability of their influence in regard to farmers decisions in vegetable marketing. From the 13 explanatory variables included in the binary logistic regression model, six predictors were found to be statistically significant in determining the effects of participation decision on vegetable market. These variables are as follows: household family size, total land holding of the household, amount of vegetable produced and marketed, use of irrigation technologies, contact with extension agents, and access to market information. Relying on a survey result and observations, the findings of the study indicated that vegetable marketing is significantly improving the livelihood of smallholder producers. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
|
Publication Date |
2017-12-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4438 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:154141 |
Serial |
6210 |
Permanent link to this record |
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|
|
Author |
Khalil-Allafi, J.; Amin-Ahmadi, B. |
Title |
Effect of mold hardness on microstructure and contraction porosity in ductile cast iron |
Type |
A1 Journal article |
Year |
2011 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of iron and steel research international |
Abbreviated Journal |
J Iron Steel Res Int |
Volume |
18 |
Issue |
4 |
Pages |
44-47 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The effect of mold hardness on the microstructure of ductile iron and the contraction porosity was investigated. Molds with different hardnesses (0.41, 0.48, 0.55, 0.62 MPa) and a sand mold prepared by Co2 method were used. The influence of silicon content on the induced expansion pressure owing to the formation of graphite was also investigated. The contraction during solidification can be compensated by an induced expansion owing to the graphite relief when the hardness of mold increases; therefore, the possibility of achieving a sound product without using any riser increases. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2011-05-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1006-706X; |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
0.836 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.836; 2011 IF: 0.213 |
Call Number |
UA @ lucian @ c:irua:122044 |
Serial |
823 |
Permanent link to this record |
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|
|
Author |
Khalil-Allafi, J.; Amin-Ahmadi, B. |
Title |
Influence of mold preheating and silicon content on microstructure and casting properties of ductile iron in permanent mold |
Type |
A1 Journal article |
Year |
2011 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of iron and steel research international |
Abbreviated Journal |
J Iron Steel Res Int |
Volume |
18 |
Issue |
3 |
Pages |
34-39 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The effects of the mold preheating and the silicon content of ductile iron on the percentage of carbides, graphite nodule counts and shrinkage volume were investigated. The results showed that the percentage of carbides and the shrinkage volume decreased when the mold preheating increased. The ductile iron with the carbon equivalent of 4.45% and the silicon content of 2.5% without any porosity defects was achieved when the mold preheating was 450 °C. Increasing the silicon content in the range of 2.1%3.3% led to the increase in graphite nodule count and graphite size and the decrease in percentage of carbides. It is due to the increase in induced expansion pressure during the graphite formation with the increasing of silicon content. The suitable condition for casting a sound product of ductile iron without the riser at the mold preheating temperature of 300 °C is the silicon content of 3.3% and carbon equivalent of 4.7%. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2011-03-28 |
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 |
|
ISSN |
1006-706X; |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
0.836 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.836; 2011 IF: 0.213 |
Call Number |
UA @ lucian @ c:irua:122043 |
Serial |
1629 |
Permanent link to this record |
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|
Author |
Tytgat, T.; Hauchecorne, B.; Smits, M.; Verbruggen, S.; Lenaerts, S. |
Title |
Concept and validation of a fully automated photocatalytic test setup |
Type |
A1 Journal article |
Year |
2012 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of laboratory automation |
Abbreviated Journal |
Jala-J Lab Autom |
Volume |
17 |
Issue |
2 |
Pages |
134-143 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
Photocatalytic activity can be studied by several methods, each with its own strengths and weaknesses. To study photocatalytic activity in an easy, user-friendly, and realistic way, a completely new setup has been built. The setup is modularly constructed around Fourier transform infrared spectroscopy (FTIR) spectroscopy at the heart of it, resulting in great versatility. Complementary software has been written for automatic control of the setup and for processing the generated data. Two pollutants, oil and n-octane, are tested to validate the performance of the setup. These validation experiments confirm the usefulness and added value of the setup in general and of the FTIR detection methodology as well. It becomes clear that a system of online measurements with good repeatability, accuracy, and user-friendliness has been created. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000304775300006 |
Publication Date |
2014-07-23 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2211-0682 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.85 |
Times cited |
15 |
Open Access |
|
Notes |
; The authors disclosed receipt of the following financial support for the research and/or authorship of this article: This work was supported by a Ph.D. grant (T. Tytgat) funded by the Institute of Innovation by Science and Technology in Flanders (IWT) and by a Ph.D. grant (S. Verbruggen) from the Research Foundation of Flanders (FWO). Other funding was made possible by the University of Antwerp. ; |
Approved |
Most recent IF: 2.85; 2012 IF: 1.457 |
Call Number |
UA @ admin @ c:irua:96649 |
Serial |
5935 |
Permanent link to this record |
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Author |
Fitawok, M.B.; Derudder, B.; Minale, A.S.; Van Passel, S.; Adgo, E.; Nyssen, J. |
Title |
Stakeholder perspectives on farmers' resistance towards urban land-use changes in Bahir Dar, Ethiopia |
Type |
A1 Journal article |
Year |
2023 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of land use science |
Abbreviated Journal |
|
Volume |
18 |
Issue |
1 |
Pages |
25-38 |
Keywords |
A1 Journal article; Engineering Management (ENM) |
Abstract |
Owing to growing uncontrolled land-use change and urban expansion, farmers in urban fringes are struggling to sustain their livelihood. Farmers have been expressing their dissatisfaction at different times. This study analyzes the stakeholders' perspectives on the causes and outcomes of farmers' resistance to land-use change and urban expansion processes by zooming in on Bahir Dar, Ethiopia. The paper is based on focus group discussions with farmers in the neighboring villages, local agricultural extension experts, and, subsequently, key informant interviews of local government officials. Juxtaposing farmers' and local experts' positions reveals that inadequate compensations during land expropriation, lack of good governance in the urban expansion process, and inaccessibility of infrastructures are primary reasons for the farmers' struggle against urban expansion in the urban fringes. This study provides insights into the consequences of unplanned urban development challenges and may inform research and policymaking on sustainable urban development in the area and beyond. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000936397600001 |
Publication Date |
2023-02-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1747-423x; 1747-4248 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.2 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.2; 2023 IF: NA |
Call Number |
UA @ admin @ c:irua:195109 |
Serial |
7368 |
Permanent link to this record |
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Author |
Borkowski, R.; Straub, M.; Ou, Y.; Lefevre, Y.; Jelić, Ž.L.; Lanneer, W.; Kaneda, N.; Mahadevan, A.; Hueckstaedt, V.; van Veen, D.; Houtsma, V.; Coomans, W.; Bonk, R.; Maes, J. |
Title |
FLCS-PON : a 100 Gbit/s flexible passive optical network: concepts and field trial |
Type |
A1 Journal article |
Year |
2021 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal Of Lightwave Technology |
Abbreviated Journal |
J Lightwave Technol |
Volume |
39 |
Issue |
16 |
Pages |
5314-5324 |
Keywords |
A1 Journal article; Mass communications; Condensed Matter Theory (CMT) |
Abstract |
We demonstrate concepts and results of a field trial for a flexible-rate passive optical network (FLCS-PON), which delivers bitrates up to 100 Gbit/s and allows for adaptations in the transmission method to match the users' channel conditions and optimize throughput. FLCS-PON builds on top of the hardware ecosystem that will be developed for ITU-T 50 Gbit/s PON and employs three new ingredients: optical network unit (ONU) grouping, flexible modulation format, and flexible forward error correction (FEC) code rate. Together, these techniques take advantage of the optical distribution network (ODN) statistics to realize a system capable of more than twofold throughput increase compared to the upcoming 50 Gbit/s PON, but still able to support a full array of deployed fiber edge cases, which are problematic for legacy PONs. In this paper we explain the concepts behind enabling techniques of FLCS-PON. We then report on a field trial over a deployed fiber infrastructure, using a system consisting of one FLCS-PON OLT and two ONUs. We report both pre- and post-forward-error-correction (post-FEC) performance of our system, demonstrating achievable net bitrate over an operator's fiber infrastructure. We realize a downlink transmission at double the speed of ITU-T 50 Gbit/s PON for ONUs exhibiting lower optical path loss (OPL), while simultaneously continue to support ONUs at high OPLs. We additionally realize a record-high 31.5 dB loss budget for 100 Gbit/s transmission using a direct-detection ONU with an optical preamplifier. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000692209800017 |
Publication Date |
2021-08-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0733-8724 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.671 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 3.671 |
Call Number |
UA @ admin @ c:irua:181586 |
Serial |
6995 |
Permanent link to this record |
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Author |
Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerof, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.; Park, Y.W. |
Title |
The superconducting bismuth-based mixed oxides |
Type |
A1 Journal article |
Year |
2003 |
Publication ![sorted by Publication field, ascending order (up)](img/sort_asc.gif) |
Journal of low temperature physics
T2 – International Conference on Physics and Chemistry of Molecular and Oxide, Superconductors (MOS2002), AUG 13-18, 2002, HSINCHU, TAIWAN |
Abbreviated Journal |
J Low Temp Phys |
Volume |
131 |
Issue |
3-4 |
Pages |
575-587 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The present paper describes the synthesis, characterization of mixed-valence bismuthates with 3- or 2-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12K exists in the narrow range (x approximate to 0.5 – 0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the 3-dimensional octahedral framework has close to the ideal perovskite structure arrangement. At the same time compositions with close to optimal Bi-valence (x = 0.33 and 0.43) do not show any sign of superconductivity, probably, due to structural distortions. The layered type (BaK)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated Buckling of the (BiO2) layers in the structure of the n = 2 member was revealed The formation of the n=1 bismuthate was found by Electron Microscopy and X-ray powder diffraction studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
|
Language |
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Wos |
000181768000061 |
Publication Date |
2003-04-07 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-2291; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.3 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.3; 2003 IF: 1.171 |
Call Number |
UA @ lucian @ c:irua:102803 |
Serial |
3597 |
Permanent link to this record |