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Records |
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Author |
van der Snickt, G.; Janssens, K.; Dik, J.; de Nolf, W.; Vanmeert, F.; Jaroszewicz, J.; Cotte, M.; Falkenberg, G.; Van der Loeff, L. |
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Title |
Combined use of synchrotron radiation based micro-X-ray fluorescence, micro-X-ray diffraction, micro-X-ray absorption near-edge, and micro-fourier transform infrared spectroscopies for revealing an alternative degradation pathway of the pigment cadmium yellow in a painting by Van Gogh |
Type |
A1 Journal article |
| |
Year  |
2012 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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| |
Volume |
84 |
Issue |
23 |
Pages |
10221-10228 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
Over the past years a number of studies have described the instability of the pigment cadmium yellow (CdS). In a previous paper we have shown how cadmium sulfide on paintings by James Ensor oxidizes to CdSO4 center dot H2O. The degradation process gives rise to the fading of the bright yellow color and the formation of disfiguring white crystals that are present on the paint surface in approximately 50 mu m sized globular agglomerations. Here, we study cadmium yellow in the painting “Flowers in a blue vase” by Vincent van Gogh. This painting differs from the Ensor case in the fact that (a) a varnish was superimposed onto the degraded paint surface and (b) the CdS paint area is entirely covered with an opaque crust. The latter obscures the yellow color completely and thus presents a seemingly more advanced state of degradation. Analysis of a cross-sectioned and a crushed sample by combining scanning microscopic X-ray diffraction (mu-XRD), microscopic X-ray absorption near-edge spectroscopy (mu-XANES), microscopic X-ray fluorescence (mu-XRF) based chemical state mapping and scanning microscopic Fourier transform infrared (mu-FT-IR) spectrometry allowed unravelling the complex alteration pathway. Although no crystalline CdSO4 compounds were identified on the Van Gogh paint samples, we conclude that the observed degradation was initially caused by oxidation of the original CdS pigment, similar as for the previous Ensor case. However, due to the presence of an overlying varnish containing lead-based driers and oxalate ions, secondary reactions took place. In particular, it appears that upon the photoinduced oxidation of its sulfidic counterion, the Cd2+ ions reprecipitated at the paint/varnish interface after having formed a complex with oxalate ions that themselves are considered to be degradation products of the resin and/or oil in the varnish. The SO42- anions, for their part, found a suitable reaction partner in Pb2+ ions stemming from a dissolved lead-based siccative that was added to the varnish to promote its drying. The resulting opaque anglesite compound in the varnish, in combination with the underlying CdC2O4 layer at the paint/varnish interface, account for the orange-gray crust that is disfiguring the painting on a macroscopic level. In this way, the results presented in this paper demonstrate how, through a judicious combined use of several microanalytical methods with speciation capabilities, many new insights can be obtained from two minute, but highly complex and heterogeneous paint samples. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000311815300013 |
Publication Date |
2012-08-30 |
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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 |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
59 |
Open Access |
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Notes |
; This research was supported by BELSPO via the Interuniversity Attraction Poles Programme (IUAP VI/16) and the S2-ART project (SD/RI/04A) and funded by Grants from the ESRF (EC-442) and PETRA-III (I-20120312 EC). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Kroller-Muller Museum and painting conservators Margje Leeuwestein and Esther Van Duijn are acknowledged for this pleasant cooperation and the authorization for the publication of the images in this article. ; |
Approved |
Most recent IF: 6.32; 2012 IF: 5.695 |
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| |
Call Number |
UA @ admin @ c:irua:105971 |
Serial |
5526 |
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| Permanent link to this record |
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Author |
Bertrand, L.; Robinet, L.; Thoury, M.; Janssens, K.; Cohen, S.X.; Schöder, S. |
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Title |
Cultural heritage and archaeology materials studied by synchrotron spectroscopy and imaging |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
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| |
Volume |
106 |
Issue |
2 |
Pages |
377-396 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The use of synchrotron radiation techniques to study cultural heritage and archaeological materials has undergone a steep increase over the past 10-15 years. The range of materials studied is very broad and encompasses painting materials, stone, glass, ceramics, metals, cellulosic and wooden materials, and a cluster of organic-based materials, in phase with the diversity observed at archaeological sites, museums, historical buildings, etc. Main areas of investigation are: (1) the study of the alteration and corrosion processes, for which the unique non-destructive speciation capabilities of X-ray absorption have proved very beneficial, (2) the understanding of the technologies and identification of the raw materials used to produce archaeological artefacts and art objects and, to a lesser extent, (3) the investigation of current or novel stabilisation, conservation and restoration practices. In terms of the synchrotron methods used, the main focus so far has been on X-ray techniques, primarily X-ray fluorescence, absorption and diffraction, and Fourier-transform infrared spectroscopy. We review here the use of these techniques from recent works published in the field demonstrating the breadth of applications and future potential offered by third generation synchrotron techniques. New developments in imaging and advanced spectroscopy, included in the UV/visible and IR ranges, could even broaden the variety of materials studied, in particular by fostering more studies on organic and complex organic-inorganic mixtures, while new support activities at synchrotron facilities might facilitate transfer of knowledge between synchrotron specialists and users from archaeology and cultural heritage sciences. |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000299749000009 |
Publication Date |
2011-11-25 |
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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 |
0947-8396 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.455 |
Times cited |
55 |
Open Access |
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Notes |
; The authors acknowledge the critical reading by B. Berrie (National Gallery of Art, Washington DC, USA). We thank J. Mass (Conservation Department, Winterthur Museum and Country Estate, Winterthur, DE, USA), H. Roemich (Institute of Fine Arts, New York University, USA), J. Hiller (Non-Crystalline Diffraction Beamline, Diamond Light Source, Didcot, UK) and J.-P. Echard (Laboratoire de recherche et de restauration, Musee de la musique, Paris, France) for their comments on the presentation of their work in the manuscript. The IPANEMA platform is jointly developed by CNRS, MNHN, the French Ministry of Culture and Communication and SOLEIL, and benefits from a CPER grant (MESR, Region Ile-de-France). Support by the Access to Research Infrastructures activity in the 7th Framework Programme of the EU (CHARISMA Grant Agreement n. 228330) and the NWO Science4Arts programme are acknowledged. ; |
Approved |
Most recent IF: 1.455; 2012 IF: 1.545 |
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Call Number |
UA @ admin @ c:irua:99166 |
Serial |
5561 |
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| Permanent link to this record |
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Author |
Smits, M.; Vanpachtenbeke, F.; Horemans, B.; De Wael, K.; Hauchecorne, B.; Van Langenhove, H.; Demeestere, K.; Lenaerts, S. |
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Title |
Effect of operating and sampling conditions on the exhaust gas composition of small-scale power generators |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
PLoS ONE |
Abbreviated Journal |
Plos One |
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Volume |
7 |
Issue |
3 |
Pages |
e32825-e32825,10 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These generators are used in different operating conditions than road-transport vehicles, resulting in different emission characteristics. Experimental data were obtained for gaseous volatile organic compounds (VOC) and PM mass concentration, elemental composition and nitrate content. The exhaust composition depends on load condition because of its effect on fuel consumption, engine wear and combustion temperature. Higher load conditions result in lower PM concentration and sharper edged particles with larger aerodynamic diameters. A positive correlation with load condition was found for K, Ca, Sr, Mn, Cu, Zn and Pb adsorbed on PM, elements that originate from lubricating oil or engine corrosion. The nitrate concentration decreases at higher load conditions, due to enhanced nitrate dissociation to gaseous NO at higher engine temperatures. Dilution on the other hand decreases PM and nitrate concentration and increases gaseous VOC and adsorbed metal content. In conclusion, these data show that operating and sampling conditions have a major effect on the exhaust gas composition of small-scale diesel generators. Therefore, care must be taken when designing new experiments or comparing literature results. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000303836500012 |
Publication Date |
2012-03-19 |
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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 |
1932-6203 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.806 |
Times cited |
5 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.806; 2012 IF: 3.730 |
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Call Number |
UA @ admin @ c:irua:96545 |
Serial |
5581 |
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Author |
Cagno, S.; Favaretto, L.; Mendera, M.; Izmer, A.; Vanhaecke, F.; Janssens, K. |
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Title |
Evidence of early medieval soda ash glass in the archaeological site of San Genesio (Tuscany) |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of archaeological science |
Abbreviated Journal |
J Archaeol Sci |
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Volume |
39 |
Issue |
5 |
Pages |
1540-1552 |
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Keywords |
A1 Journal article; Philosophy; History; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The early medieval period marks an important turning point in the history of glassmaking, since it comprises the transition period between the mineral-based silica-soda-lime glass of the Roman tradition and the plant ash-based glass. With the aim of expanding the knowledge on the glass recipes and technologies of this period, 37 glass samples were analyzed, originating from the archaeological excavations of San Genesio (Tuscany) and dated from the fourth to the eleventh century. The major and minor element concentrations were measured with SEM-EDX, while the trace elements were quantified with LA-ICP-MS. The results were compared with published compositions of glass samples of similar age in order to highlight differences and similarities. The results offer a very interesting view on the glass circulation in the religious/residential/manufacturing center of San Genesio in the early medieval period. Most of the glass has a typical late-Roman composition, but some glass fragments are identified as soda ash glass. These are among the earliest medieval ash-fluxed glasses ever found in the Italian peninsula. (C) 2011 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000301620900034 |
Publication Date |
2012-01-02 |
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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 |
0305-4403 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.602 |
Times cited |
24 |
Open Access |
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Notes |
; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ; |
Approved |
Most recent IF: 2.602; 2012 IF: 1.889 |
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Call Number |
UA @ admin @ c:irua:98251 |
Serial |
5618 |
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| Permanent link to this record |
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Author |
Bruijnen, Y.; Caen, J.M.A.; Cagno, S.; Janssens, K.; et al. |
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Title |
Getekend Jan R. : Jan Rombouts, een renaissancemeester herontdekt |
Type |
ME2 Book as editor or co-editor |
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Year |
2012 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
207 p. |
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Keywords |
ME2 Book as editor or co-editor; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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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 |
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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 |
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ISBN |
978-90-6153-780-9 |
Additional Links |
UA library record |
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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 |
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Call Number |
UA @ admin @ c:irua:115160 |
Serial |
5633 |
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Author |
Tilleman, L.; De Henau, S.; Pauwels, M.; Nagy, N.; Pintelon, I.; Braeckman, B.P.; De Wael, K.; Van Doorslaer, S.; Adriaensen, D.; Timmermans, J.-P.; Moens, L.; Dewilde, S. |
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Title |
An N-myristoylated globin with a redox-sensing function that regulates the defecation cycle in Caenorhabditis elegans |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
PLoS ONE |
Abbreviated Journal |
Plos One |
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Volume |
7 |
Issue |
12 |
Pages |
e48768-9 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Globins occur in all kingdoms of life where they fulfill a wide variety of functions. In the past they used to be primarily characterized as oxygen transport/storage proteins, but since the discovery of new members of the globin family like neuroglobin and cytoglobin, more diverse and complex functions have been assigned to this heterogeneous family. Here we propose a function for a membrane-bound globin of C. elegans, GLB-26. This globin was predicted to be myristoylated at its N-terminus, a post-translational modification only recently described in the globin family. In vivo, this globin is found in the membrane of the head mesodermal cell and in the tail stomato-intestinal and anal depressor muscle cells. Since GLB-26 is almost directly oxidized when exposed to oxygen, we postulate a possible function as electron transfer protein. Phenotypical studies show that GLB-26 takes part in regulating the length of the defecation cycle in C. elegans under oxidative stress conditions. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000313236200008 |
Publication Date |
2012-12-12 |
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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 |
1932-6203 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.806 |
Times cited |
6 |
Open Access |
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Notes |
; SDH is a Ph.D. fellow of the Fund for Scientific Research (FWO). Financial support to SD and LM was provided by the University of Antwerp (BOF UA TOP 2006) and to SD, LM, BPB, by FWO project G.0247.09. The UltraVIEW VoX spinning disk confocal microscope was purchased with support of the Hercules Foundation (Hercules Type 1: AUHA 09/001). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; |
Approved |
Most recent IF: 2.806; 2012 IF: 3.730 |
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Call Number |
UA @ admin @ c:irua:102591 |
Serial |
5741 |
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| Permanent link to this record |
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Author |
Cagno, S.; Badano, M.B.; Mathis, F.; Strivay, D.; Janssens, K. |
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Title |
Study of medieval glass fragments from Savona (Italy) and their relation with the glass produced in Altare |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of archaeological science |
Abbreviated Journal |
J Archaeol Sci |
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Volume |
39 |
Issue |
7 |
Pages |
2191-2197 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Altare was in the medieval and post-medieval period an important glassmaking center in the Liguria region in Northern Italy. The first historical evidence of glassmaking in Altare is dated to the twelfth century. In spite of that, due to the continuity of glassmaking up to the present time and the contemporaneous intensive urbanization of the territory, no medieval glass from Altare or its immediate vicinity has been analyzed up to now. In this work, glass from archaeological excavations in the center of Savona, city with close ties with the glassmaking center, was studied. Glass fragments, dated from the tenth to the sixteenth century were selected from the collections of the Archaeological Museum in Savona and non-destructively analyzed with quantitative PIXE-PIGE. The resulting compositions, compared with known glass productions of the same time and evaluated on the basis of historical documents, offer an interesting panorama on the variety of glass circulation in Liguria. (C) 2012 Elsevier Ltd. 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 |
000305849400027 |
Publication Date |
2012-03-29 |
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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 |
0305-4403 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.602 |
Times cited |
21 |
Open Access |
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Notes |
; This research was supported by the Interuniversity Attraction Poles Programme – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. The authors gratefully acknowledge Prof. Carlo Varaldo for allowing the study of the glass preserved in the Archaeological Museum of Savona. ; |
Approved |
Most recent IF: 2.602; 2012 IF: 1.889 |
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Call Number |
UA @ admin @ c:irua:100332 |
Serial |
5849 |
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Author |
De Keersmaecker, M.; De Wael, K.; Adriaens, A. |
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Title |
The use of lead dodecanoate as an environmentally friendly coating to inhibit the corrosion of lead objects : comparison of three different deposition methods |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Progress in organic coatings |
Abbreviated Journal |
Prog Org Coat |
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Volume |
74 |
Issue |
1 |
Pages |
1-7 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
An aqueous sodium dodecanoate solution has been used for the formation of a protective coating for lead. Three deposition methods have been compared: immobilization using cyclic voltammetry, immersion and amperometry. Apart from this, we tested a reduction pretreatment of the lead surface (−1.5 V during 600 s) in order to obtain a more reproducible coating, resulting in a better corrosion protection behavior. The corrosion inhibition properties were examined using potentiodynamic polarization curves and electrochemical impedance measurements in a standard corrosive environment. |
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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 |
000302585300001 |
Publication Date |
2012-02-16 |
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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 |
0300-9440; 0033-0655 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.858 |
Times cited |
8 |
Open Access |
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Notes |
; The Research Foundation – Flanders (FWO) and Ghent University are acknowledged for funding this work. The authors would like to thank Pieter Van Hoe for the production of the embedded lead electrodes. They also acknowledge Pieter Arickx and Jonas Van Damme for their contribution. ; |
Approved |
Most recent IF: 2.858; 2012 IF: 1.848 |
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Call Number |
UA @ admin @ c:irua:96354 |
Serial |
5894 |
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| Permanent link to this record |
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Author |
Tytgat, T.; Hauchecorne, B.; Smits, M.; Verbruggen, S.; Lenaerts, S. |
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Title |
Concept and validation of a fully automated photocatalytic test setup |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of laboratory automation |
Abbreviated Journal |
Jala-J Lab Autom |
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Volume |
17 |
Issue |
2 |
Pages |
134-143 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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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. |
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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 |
000304775300006 |
Publication Date |
2014-07-23 |
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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 |
2211-0682 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.85 |
Times cited |
15 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:96649 |
Serial |
5935 |
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| Permanent link to this record |
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Author |
Smits, M.; Tytgat, T.; Hauchecorne, B.; Lenaerts, S. |
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| |
Title |
Development and validation of optical detection methods to screen photocatalytic materials for soot oxidation |
Type |
P3 Proceeding |
| |
Year |
2012 |
Publication |
|
Abbreviated Journal |
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| |
Volume |
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Issue |
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Pages |
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Keywords |
P3 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
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Address |
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Corporate Author |
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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 |
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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 |
|
|
| |
ISSN |
|
ISBN |
978-989-97667-4-7 |
Additional Links |
UA library record |
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| |
Impact Factor |
|
Times cited |
|
Open Access |
|
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| |
Notes |
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Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ admin @ c:irua:98814 |
Serial |
5941 |
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| Permanent link to this record |
| |
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| |
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Author |
Smits, M.; Vanpachtenbeke, F.; Hauchecorne, B.; van Langenhove, H.; Demeestere, K.; Lenaerts, S. |
|
| |
Title |
Exhaust composition of a small diesel engine |
Type |
A2 Journal article |
| |
Year |
2012 |
Publication |
Communications in agricultural and applied biological sciences |
Abbreviated Journal |
|
|
| |
Volume |
77 |
Issue |
1 |
Pages |
85-88 |
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| |
Keywords |
A2 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
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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 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
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Edition |
|
|
| |
ISSN |
1379-1176 |
ISBN |
|
Additional Links |
UA library record |
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| |
Impact Factor |
|
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: NA |
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| |
Call Number |
UA @ admin @ c:irua:94166 |
Serial |
5949 |
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| Permanent link to this record |
| |
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| |
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Author |
Smits, M.; Ling, Y.; Lenaerts, S.; Van Doorslaer, S. |
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| |
Title |
Photocatalytic removal of soot : unravelling of the reaction mechanism by EPR and in situ FTIR spectroscopy |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
ChemPhysChem : a European journal of chemical physics and physical chemistry |
Abbreviated Journal |
Chemphyschem |
|
| |
Volume |
13 |
Issue |
18 |
Pages |
4251-4257 |
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| |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
|
| |
Abstract |
Photocatalytic soot oxidation is studied on P25 TiO2 as an important model reaction for self-cleaning processes by means of electron paramagnetic resonance (EPR) and Fourier transform infrared (FTIR) spectroscopy. Contacting of carbon black with P25 leads on the one hand to a reduction of the local dioxygen concentration in the powder. On the other hand, the weakly adsorbed radicals on the carbon particles are likely to act as alternative traps for the photogenerated conduction-band electrons. We find furthermore that the presence of dioxygen and oxygen-related radicals is vital for the photocatalytic soot degradation. The complete oxidation of soot to CO2 is evidenced by in situ FTIR spectroscopy, no intermediate CO is detected during the photocatalytic process. |
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| |
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 |
000313692600026 |
Publication Date |
2012-11-13 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1439-4235 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.075 |
Times cited |
9 |
Open Access |
|
|
| |
Notes |
; This work was supported by the University of Antwerp (PhD grants of M. S. and Y.L.). We would like to thank Birger Hauchecorne for the scientific discussion. ; |
Approved |
Most recent IF: 3.075; 2012 IF: 3.349 |
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| |
Call Number |
UA @ admin @ c:irua:104568 |
Serial |
5980 |
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| Permanent link to this record |
| |
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| |
|
Author |
Van Passel, S.; Meul, M. |
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| |
Title |
Multilevel and multi-user sustainability assessment of farming systems |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Environmental Impact Assessment Review |
Abbreviated Journal |
Environ Impact Asses |
|
| |
Volume |
32 |
Issue |
1 |
Pages |
170-180 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology |
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| |
Abstract |
Sustainability assessment is needed to build sustainable farming systems. A broad range of sustainability concepts, methodologies and applications already exists. They differ in level, focus, orientation, measurement, scale, presentation and intended end-users. In this paper we illustrate that a smart combination of existing methods with different levels of application can make sustainability assessment more profound, and that it can broaden the insights of different end-user groups. An overview of sustainability assessment tools on different levels and for different end-users shows the complementarities and the opportunities of using different methods. In a case-study, a combination of the sustainable value approach (SVA) and MOTIFS is used to perform a sustainability evaluation of farming systems in Flanders. SVA is used to evaluate sustainability at sector level, and is especially useful to support policy makers, while MOTIFS is used to support and guide farmers towards sustainability at farm level. The combined use of the two methods with complementary goals can widen the insights of both farmers and policy makers, without losing the particularities of the different approaches. To stimulate and support further research and applications, we propose guidelines for multilevel and multi-user sustainability assessments. |
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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 |
000297874000020 |
Publication Date |
2011-09-21 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0195-9255 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.094 |
Times cited |
49 |
Open Access |
|
|
| |
Notes |
; ; |
Approved |
Most recent IF: 3.094; 2012 IF: 1.851 |
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| |
Call Number |
UA @ admin @ c:irua:94186 |
Serial |
6231 |
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| Permanent link to this record |
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| |
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Author |
Meul, M.; Van Passel, S.; Fremaut, D.; Haesaert, G. |
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| |
Title |
Higher sustainability performance of intensive grazing versus zero-grazing dairy systems |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Agronomy For Sustainable Development |
Abbreviated Journal |
Agron Sustain Dev |
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| |
Volume |
32 |
Issue |
3 |
Pages |
629-638 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
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| |
Abstract |
Although grazing of dairy cows is an integral part of dairy farming in many European countries, farmers today more often choose for zero-grazing systems, where cows are housed throughout the year. Some studies already compared grazing and zero-grazing systems for specific issues such as labor efficiency, environmental impact, or animal welfare. In our study, we perform a more integrated evaluation, considering relevant ecological, economic, and social aspects. This allows for a balanced and more complete comparison of the sustainability performance of the two production methods. We evaluated ten intensive grazing and ten zero-grazing specialized Flemish dairy farms on the use of nutrients and energy, productivity and profitability, labor input, and animal welfare. In addition, we put special effort in formulating useful management advice for farmers. Therefore, we combined a detailed analysis of the sustainability indicators with an intensive interaction and discussion with farmers and farm advisors. Results show that, on average, the zero-grazing farms performed significantly worse from an ecological and economic point of view. This fact is explained mainly due to a less efficient use of concentrates and byproducts. Social sustainability performance did not differ significantly between the two groups. As a result, the integrated sustainability performance was significantly lower for the zero-grazing group. This finding shows that a further shift from intensive grazing to zero-grazing can move dairy farming in Flanders further away from sustainability. An important advice to improve the ecological and economic performance of zero-grazing farms is to optimize cows' rations to include more forages and optimize forage production and use. More detailed site- and case-specific management advice for farmers of both groups was provided during a discussion meeting. We consider this an essential additional step to any sustainability evaluation, since progress can only be made when monitoring results are translated into practical measures. |
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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 |
000306061800003 |
Publication Date |
2012-01-11 |
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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 |
1774-0746 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.101 |
Times cited |
26 |
Open Access |
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| |
Notes |
; ; |
Approved |
Most recent IF: 4.101; 2012 IF: 3.573 |
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| |
Call Number |
UA @ admin @ c:irua:127557 |
Serial |
6209 |
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| Permanent link to this record |
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Author |
Van Dael, M.; Van Passel, S.; Pelkmans, L.; Guisson, R.; Swinnen, G.; Schreurs, E. |
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| |
Title |
Determining potential locations for biomass valorization using a macro screening approach |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Biomass & Bioenergy |
Abbreviated Journal |
Biomass Bioenerg |
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Volume |
45 |
Issue |
|
Pages |
175-186 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
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Abstract |
European policy states that by 2020 at least 20% of final energy consumption should come from renewable energy sources. Biomass as a renewable energy source cannot be disregarded in order to attain this target. In this study a macro screening approach is developed to determine potential locations for biomass valorization in a specified region. The approach consists of five steps: (1) criteria determination, (2) data gathering, (3) weight assignment, (4) final score, (5) spatial representation. The resulting outcome provides a first well balanced scan of the possibilities for energy production using regional biomass. This way policy makers and investors can be supported and motivated to study the possibilities of building energy production plants at specific locations in more detail, which can be described as a 'micro-screening'. In our case study the approach is applied to determine the potentially interesting locations to establish a biomass project. The region has been limited to the forty-four communities in the province of Limburg (Belgium). The macro screening approach has shown to be very effective since the amount of interesting locations has been reduced drastically. (c) 2012 Elsevier Ltd. All rights reserved. |
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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 |
000308384500019 |
Publication Date |
2012-06-30 |
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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 |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0961-9534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.219 |
Times cited |
23 |
Open Access |
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Notes |
; The authors gratefully acknowledge the financial support from INTERREG and the province of Limburg. Special thanks to our colleague Thomas Voets for his effort in making the GIS maps. Moreover, the authors would like to thank the two anonymous reviewers for their valuable comments. ; |
Approved |
Most recent IF: 3.219; 2012 IF: 2.975 |
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Call Number |
UA @ admin @ c:irua:127554 |
Serial |
6178 |
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| Permanent link to this record |
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Author |
Margui, E.; Hidalgo, M.; Queralt, I.; van Meel, K.; Fontas, C. |
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Title |
Analytical capabilities of laboratory, benchtop and handheld X-ray fluorescence systems for detection of metals in aqueous samples pre-concentrated with solid-phase extraction disks |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
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Volume |
67 |
Issue |
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Pages |
17-23 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
We aimed to achieve improved instrumental sensitivity and detection limits for the analysis of several elements (Cu, Ni, Zn, Pb and Cd) in aqueous samples with energy dispersive X-ray fluorescence spectrometry (EDXRF). The metals were pre-concentrated from aqueous solutions using commercially available organic-based solid-phase extraction (SPE) disks functionalized with iminodiacetate groups. These thin-layer organic materials provide an ideal support for XRF analysis. The elements were collected on the SPE extraction disks using a simple filtration procedure (starting with 1 L of aqueous sample) that allows direct XRF measurements to be performed in the field (in situ). We evaluated the analytical possibilities and drawbacks of using this pre-concentration procedure in combination with the following XRF configurations: a handheld unit, a benchtop EDXRF system and a high-energy polarized-beam EDXRF instrument (HE-P-EDXRF). Using the HE-P-EDXRF system, the detection limits for all metals were more than one order of magnitude lower than those attained using handheld and benchtop EDXRF instrumentation. For the detection of metal concentrations higher than similar to 20 mu g/L, however, handheld or benchtop systems remain a very good option due to their extreme simplicity of operation and low-cost, compact design. We demonstrate the application of these methodologies, using the three equipment systems, to the analysis of trace concentrations of metals in different types of aqueous samples, including tap water and waste water. (C) 2011 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 |
000302757200003 |
Publication Date |
2011-12-19 |
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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 |
|
Series Issue |
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Edition |
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ISSN |
0584-8547; 1873-3565 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:98338 |
Serial |
7454 |
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| Permanent link to this record |
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Author |
Fenu, A.; De Wilde, W.; Gaertner, M.; Weemaes, M.; de Gueldre, G.; van de Steene, B. |
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Title |
Elaborating the membrane life concept in a full scale hollow-fibers MBR |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of membrane science |
Abbreviated Journal |
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| |
Volume |
421 |
Issue |
|
Pages |
349-354 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
The membrane life-time has a strong impact on competitivity and viability of MBRs. This study critically analyzes the membrane life-time concept, approaching it through different assessment methods. A full scale MBR's membrane life-time was assessed on the following: (i) maintaining the permeate flow throughput to the MBR; (ii) the permeability decline; (iii) oxidative aging; (iv) the increase in energy costs; and (v) mechanical aging. The method based on permeability decline provides a membrane life-time estimate up to a theoretical end. It was further elaborated inherently to operations with no long-term flux decline. The increase in operating pressure remains the main end-of-life trigger for deciding when to replace membrane modules. On the contrary, mechanical and permeate flow throughput analysis of the data are not able to provide a clear estimate of the membrane life-time. As for the membrane life-time estimation based on chlorine contact, it was found to be too optimistic. Complete irreversible fouling occurs before maximum contact time with chlorine is reached. At end-of-life operating conditions, the energy consumption raised of 170% due to the reduced flow rate. The cost raise appears high but still affordable. Earlier membrane replacement thus can never be counterbalanced by energy costs saving. (C) 2012 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 |
000308741100039 |
Publication Date |
2012-08-07 |
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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 |
|
Series Issue |
|
Edition |
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ISSN |
0376-7388 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:101790 |
Serial |
7856 |
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| Permanent link to this record |
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Author |
Abreu, Y.; Cruz, C.M.; van Espen, P.; Pérez, C.; Piñera, I.; Leyva, A.; Cabal, A.E. |
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Title |
Electric field gradient calculations in ZnO samples implanted with 111In(111Cd) |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Solid state communications |
Abbreviated Journal |
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| |
Volume |
152 |
Issue |
5 |
Pages |
399-402 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A first-principles study of the electric field gradient (EFG) calculated for ideal and In-111(Cd-111) implanted ZnO samples is reported in the present work. The study was made for ZnO ideal hexagonal structures and supercells were introduced in order to consider the possible implantation environments. The calculation was done using the “WIEN2k” code within the density functional theory, the exchange and correlation effects were determined by the GGA approximation. Three possible In-111(Cd-111) implantation configurations were studied, one substitutional incorporation at cation site and two interstitials. The obtained EFG values for the ideal structure and the substitutional site are in good agreement with the experimental reports measured by perturbed angular correlation (PAC) and high precision nuclear magnetic resonance (NMR). Thus, the ascription of substitutional incorporation of In-111(Cd-111) probe atom at the ZnO cation site after annealing was confirmed. (C) 2011 Elsevier Ltd. All rights reserved. |
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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 |
000301329200016 |
Publication Date |
2011-12-09 |
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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 |
|
Series Issue |
|
Edition |
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ISSN |
0038-1098 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
|
Approved |
no |
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Call Number |
UA @ admin @ c:irua:97821 |
Serial |
7857 |
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| Permanent link to this record |
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Author |
Hellar-Kihampa, H.; Potgieter-Vermaak, S.; van Meel, K.; Gatto Rotondo, G.; Kishimba, M.; Van Grieken, R. |
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Title |
Elemental composition of bottom-sediments from Pangani river basin, Tanzania : lithogenic and anthropogenic sources |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Toxicological and environmental chemistry |
Abbreviated Journal |
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| |
Volume |
94 |
Issue |
3 |
Pages |
525-544 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
River-bed sediments from the Pangani basin, Tanzania, were characterized for elemental compositions, following contamination risks from rapid expansions of human activities in the area. Samples were collected during two individual seasons and analyzed by high-polarizing beam energy dispersive X-ray fluorescence (EDXRF) for eight major and 14 trace elements. Evaluation of enrichment factors (EFs) was used to investigate the elemental flux and assess the contributions of natural and anthropogenic influences. The abundances of the major elements followed the order Si > Al > Fe > Ca > K > Ti > Mn > P, similar to that of the upper earth's crust, and were generally from the weathering of the bed-rock. The high concentrations of typical anthropogenic trace-elements (Cr < 160 mg kg−1, V < 85 mg kg−1, Ni < 60 mg kg−1, Cu < 87 mg kg−1, La < 90 mg kg−1) coupled with high EFs (>2) in some locations indicated contamination associated with agricultural and industrial activities. Factor analysis extracted five principal components that contributed to 96.0% of the total observed variance. The results indicated that river-bed sediments of the Pangani basin were influenced to a larger extent by lithogenic sources than anthropogenic impacts. |
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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 |
000304276100007 |
Publication Date |
2012-01-16 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
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| |
ISSN |
0277-2248 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
|
Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:97080 |
Serial |
7889 |
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| 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. |
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Title |
Extension of the river water quality model no. 1 with the fate of pesticides |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of hydroinformatics |
Abbreviated Journal |
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| |
Volume |
14 |
Issue |
1 |
Pages |
48-64 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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| |
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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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 |
000298618300004 |
Publication Date |
2011-10-25 |
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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 |
1464-7141 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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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 |
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Call Number |
UA @ admin @ c:irua:96257 |
Serial |
7954 |
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| Permanent link to this record |
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Author |
Godoi, R.H.M.; Hirata, P.Y.; Bitterncourt, A.V.L.; Godoi, A.F.L.; Potgieter-Vermaak, S.; Gatto Rotondo, G.; Van Grieken, R.; et al. |
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Title |
Geochemical assessment of a subtropical reservoir : a case study in Curitiba, Southern Brazil |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Clean : soil, air, water |
Abbreviated Journal |
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| |
Volume |
40 |
Issue |
4 |
Pages |
364-372 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
Suspended particles and dissolved substances in water provide reactive surfaces, influence metabolic activity and contribute to the net sediment deposition. It therefore plays an important part in the ecology and quality of the water mass. The water quality in reservoirs is crucial and it is naturally maintained by flushing and sedimentation, which continuously remove phosphorus from the water. In some reservoirs, however, these removal processes are countered by recycling of ions which could play a key role to start and/or maintain the eutrophic state. The combination of macro-, trace- and microanalysis techniques can be useful to trace pollution sources through a chemical fingerprint, whether be during an acute environmental disaster or a long-term release of pollutants. The water quality and total metal content of reservoir sediments were assessed in a reservoir, situated in the capital of the Paraná State, in the South-Eastern part of Brazil. The goal of this paper was to determine the metal presence in the sediment and metal and ionic speciation in the Green River reservoir water. Water and bed sediment samples, collected from various sites during 2008 and 2009, were investigated using XRF, ICP-OES, ICP-MS, XRD and zeta potential measurements. Based on the results, the heavy metal concentration and chemical composition of the suspended matter in the water samples, as well as the sediment's chemical composition will be discussed. |
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Wos |
000302607800005 |
Publication Date |
2012-01-05 |
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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 |
1863-0650 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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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 |
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Call Number |
UA @ admin @ c:irua:96973 |
Serial |
7993 |
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| Permanent link to this record |
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Author |
Gatto Rotondo, G.; Darchuk, L.; Swaenen, M.; Van Grieken, R. |
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Title |
Micro-Raman and SEM analysis of minerals from the Darhib mine, Egypt |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of analytical sciences, methods and instrumentation |
Abbreviated Journal |
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| |
Volume |
2 |
Issue |
1 |
Pages |
42-47 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The Darhib mine is one of the several talc deposits in the Hamata area of southeastern Egypt. Several specimens of minerals coming from this mine were subjected to complementary investigation by micro-Raman spectrometry and scanning electron microscopy. The difficulty in their identification is the appearance of most of them: they are all very small and only visible under the mineral binocular microscope(×10 – ×40). They appear as small crystals in fissures and holes and a visual determination on colour and crystal gives only a guess of what kind of mineral it could be. Therefore, only after analyzing them by micro-Raman and scanning electron microscopy it was possible to identify their structure and they can be divided in three main groups: one is quite generic and several minerals of different species were identified, such as quartz, talc, mottramite and chrysocolla, very common in the talc mine (these ones are Si-based minerals); the other one is constituted by four samples which are Zn and/or Cu rich, which means minerals of the rosasite or aurichalcite groups; the last group is constituted by two samples containing mainly Pb.. |
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Place of Publication |
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Wos |
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Publication Date |
2012-03-31 |
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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 |
2164-2745; 2164-2753 |
ISBN |
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Additional Links |
UA library record |
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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 |
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Call Number |
UA @ admin @ c:irua:102567 |
Serial |
8232 |
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| Permanent link to this record |
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Author |
Cataldo,.; Evangelista, H.; Simões, J.C.; Godoi, R.H.M.; Simmonds, I.; Hollanda, M.H.; Wainer, I.; Aquino, F.E.; Van Grieken, R. |
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Title |
Mineral dust variability in central West Antarctica associated with ozone depletion |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Atmospheric chemistry and physics discussions |
Abbreviated Journal |
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| |
Volume |
12 |
Issue |
5 |
Pages |
12685-12714 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Here we show that mineral dust retrieved from an ice core in the central West Antarctic sector, spanning the last five decades, provides evidence that northerly air mass incursions into Antarctica, tracked by dust microparticles, have slightly declined. This result contrasts with dust in ice core records reported in West/coastal Antarctica, which show significant increases to the present day. We attribute that difference, in part, to changes in the regional climate regime triggered by the ozone depletion and its consequences for the polar vortex intensity. The vortex maintains the Antarctic central region relatively isolated from mid-latitude air mass incursions with implications to the intensification of the Westerlies and to a persistent positive phase of the Southern Annular Mode. We also show that variability of the diameter of insoluble microparticles in central West Antarctica can be modeled by linear/quadratic functions of both cyclone depth (energy) and wind intensity around Antarctica. |
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Corporate Author |
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Thesis |
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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 |
2012-05-21 |
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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 |
1680-7367 |
ISBN |
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Additional Links |
UA library record |
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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 |
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| |
Call Number |
UA @ admin @ c:irua:102568 |
Serial |
8251 |
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| Permanent link to this record |
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Author |
Cabal Rodríguez, A.E.; Leyva Pernia, D.; Schalm, O.; van Espen, P.J.M. |
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Title |
Possibilities of energy-resolved X-ray radiography for the investigation of paintings |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
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| |
Volume |
402 |
Issue |
4 |
Pages |
1471-1480 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
X-ray radiographic images of paintings often show little or no contrast. In order to increase the contrast in radiographic images we measured the X-ray spectrum of a low power X-ray tube, after passing through the painting, with a high energy-resolution SDD detector. To obtain images, the detector is collimated with a 400 mu m diameter pinhole and the painting was moved through the beam in the x and y-direction using a dwell time of a few seconds per pixel. The data obtained consists of a data cube of, typically, 200 x 200 pixels and a 512-channel X-ray spectrum for each pixel, spanning the energy range from 0 to 40 keV. Having the absorbance spectrum available for each pixel, we are able, a posteriori, to produce images by edge subtraction for any given element. In this way high contrast, element-specific, images can be obtained. Because of the high energy-resolution a much simpler edge subtraction algorithm can be applied. We also used principal-component imaging to obtain, in a more automated way, images with high contrast. Some of these images can easily be attributed to specific elements. It turns out that preprocessing of the spectral data is crucial for the success of the multivariate image processing. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
000299842000008 |
Publication Date |
2011-07-14 |
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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 |
1618-2642; 1618-2650 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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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 |
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| |
Call Number |
UA @ admin @ c:irua:96200 |
Serial |
8394 |
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| Permanent link to this record |
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Author |
Oprya, M.; Kiro, S.; Worobiec, A.; Horemans, B.; Darchuk, L.; Novakovic, V.; Ennan, A.; Van Grieken, R. |
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Title |
Size distribution and chemical properties of welding fumes of inhalable particles |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of aerosol science |
Abbreviated Journal |
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| |
Volume |
45 |
Issue |
1 |
Pages |
50-57 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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Abstract |
The goal of the present study was to analyze the relationship between the fume formation rate, welding conditions, chemical composition of welding fume particles and their size. In the range from 0.25 to 16 μm aerodynamic diameter, three distinct types of welding fume particles were identified in the welder's breathing zone. The elemental composition of each type depended completely on the used welding materials, and reflects their mechanism of formation. Their relative abundance in the welding fume appeared to be dependent on the electrode coating, as well as the heat input during welding. |
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Corporate Author |
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Place of Publication |
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Wos |
000300140000005 |
Publication Date |
2011-10-26 |
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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 |
0021-8502; 1879-1964 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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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 |
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Call Number |
UA @ admin @ c:irua:93184 |
Serial |
8544 |
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| Permanent link to this record |
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Author |
Piñera, I.; Cruz, C.M.; van Espen, P.; Abreu, Y.; Leyva, A. |
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Title |
Study of dpa distributions in electron irradiated YBCO slabs through MCCM algorithm |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Nuclear instruments and methods in physics research: B: beam interactions with materials and atoms |
Abbreviated Journal |
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Volume |
274 |
Issue |
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Pages |
191-194 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The Monte Carlo assisted Classical Method (MCCM) consists on a calculation procedure for determining the displacements per atom (dpa) distribution in solid materials. This algorithm allows studying the gamma and electron irradiation damage in different materials. It is based on the electrons elastic scattering classic theories and the use of Monte Carlo simulation for the physical processes involved. The present study deals with the Monte Carlo simulation of electron irradiation effects on YBa2Cu3O7-x (YBCO) slabs using the MCNPX code system. Displacements per atom distributions are obtained through the MCCM for electron irradiation up to 10 MeV. In-depth dpa profiles for electrons and positrons are obtained and analysed. Also, dpa contributions from each atomic specie in the material are calculated. It was found that the dpa distribution is more homogeneous in the material volume when increasing energy of incident electrons. Also, the dpa produced by positrons has no relevance when irradiating with electrons, in contrast with previous similar gamma irradiation studies. All the results are presented and discussed in this contribution. (C) 2011 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Language |
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Wos |
000301611900031 |
Publication Date |
2011-12-05 |
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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 |
0168-583x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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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 |
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| |
Call Number |
UA @ admin @ c:irua:97819 |
Serial |
8595 |
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| Permanent link to this record |
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Author |
Mishra, V.K.; Kumar, P.; Van Poppel, M.; Bleux, N.; Frijns, E.; Reggente, M.; Berghmans, P.; Int Panis, L.; Samson, R. |
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Title |
Wintertime spatio-temporal variation of ultrafine particles in a Belgian city |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
The science of the total environment |
Abbreviated Journal |
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Volume |
431 |
Issue |
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Pages |
307-313 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Simultaneous measurements of ultrafine particles (UFPs) were carried out at four sampling locations situated within a 1 km(2) grid area in a Belgian city, Borgerhout (Antwerp). All sampling sites had different orientation and height of buildings and dissimilar levels of anthropogenic activities (mainly traffic volume). The aims were to investigate: (i) the spatio-temporal variation of UFP within the area, (ii) the effect of wind direction with respect to the volume of traffic on UFP levels, and (iii) the spatial representativeness of the official monitoring station situated in the study area. All sampling sites followed similar diurnal patterns of UFP variation, but effects of local traffic emissions were evident. Wind direction also had a profound influence on UFP concentrations at certain sites. The results indicated a clear influence of local weather conditions and the more dominant effect of traffic volumes. Our analysis indicated that the regional air quality monitoring station represented the other sampling sites in the study area reasonably well; temporal patterns were found to be comparable though the absolute average concentrations showed differences of up to 35%. (C) 2012 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 |
000306887900037 |
Publication Date |
2012-06-14 |
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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 |
0048-9697; 1879-1026 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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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 |
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| |
Call Number |
UA @ admin @ c:irua:101123 |
Serial |
8759 |
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| Permanent link to this record |
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Author |
van Holsbeke, C.; de Backer, J.; Vos, W.; Verdonck, P.; van Ransbeeck, P.; Claessens, T.; Braem, M.; Vanderveken, O.; de Backer, W. |
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Title |
Anatomical and functional changes in the upper airways of sleep apnea patients due to mandibular repositioning: a large scale study |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of biomechanics |
Abbreviated Journal |
J Biomech |
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Volume |
44 |
Issue |
3 |
Pages |
442-449 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) |
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Abstract |
The obstructive sleep apnea-hypopnea syndrome (OSAHS) is a sleep related breathing disorder. A popular treatment is the use of a mandibular repositioning appliance (MRA) which advances the mandibula during the sleep and decreases the collapsibility of the upper airway. The success rate of such a device is, however, limited and very variable within a population of patients. Previous studies using computational fluid dynamics have shown that there is a decrease in upper airway resistance in patients who improve clinically due to an MRA. In this article, correlations between patient-specific anatomical and functional parameters are studied to examine how MRA induced biomechanical changes will have an impact on the upper airway resistance. Low-dose computed tomography (CT) scans are made from 143 patients suffering from OSAHS. A baseline scan and a scan after mandibular repositioning (MR) are performed in order to study variations in parameters. It is found that MR using a simulation bite is able to induce resistance changes by changing the pharyngeal lumen. The change in minimal cross-sectional area is the best parameter to predict the change in upper airway resistance. Looking at baseline values, the ideal patients for MR induced resistance decrease seem to be women with short airways, high initial resistance and no baseline occlusion. |
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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, N.Y. |
Editor |
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Language |
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Wos |
000287551000014 |
Publication Date |
2010-10-23 |
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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 |
0021-9290; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.664 |
Times cited |
23 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.664; 2011 IF: 2.434 |
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Call Number |
UA @ lucian @ c:irua:85305 |
Serial |
112 |
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| Permanent link to this record |
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Author |
Karapetrov, G.; Belkin, A.; Iavarone, M.; Fedor, J.; Novosad, V.; Milošević, M.V.; Peeters, F.M. |
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Title |
Anisotropic superconductivity and vortex dynamics in magnetically coupled F/S and F/S/F hybrids |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
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Volume |
24 |
Issue |
1/2 |
Pages |
905-910 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Magnetically coupled superconductorferromagnet hybrids offer advanced routes for nanoscale control of superconductivity. Magnetotransport characteristics and scanning tunneling microscopy images of vortex structures in superconductorferromagnet hybrids reveal rich superconducting phase diagrams. Focusing on a particular combination of a ferromagnet with a well-ordered periodic magnetic domain structure with alternating out-of-plane component of magnetization, and a small coherence length superconductor, we find directed nucleation of superconductivity above the domain wall boundaries. We show that near the superconductor-normal state phase boundary the superconductivity is localized in narrow mesoscopic channels. In order to explore the Abrikosov flux line ordering in F/S hybrids, we use a combination of scanning tunneling microscopy and GinzburgLandau simulations. The magnetic stripe domain structure induces periodic local magnetic induction in the superconductor, creating a series of pinninganti-pinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-1D arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes nonlinear due to a change in both the number of vortices and the confining potential. In F/S/F hybrids we demonstrate the evolution of the anisotropic conductivity in the superconductor that is magnetically coupled with two adjacent ferromagnetic layers. Stripe magnetic domain structures in both F-layers are aligned under each other, resulting in a directional superconducting order parameter in the superconducting layer. The conductance anisotropy strongly depends on the period of the magnetic domains and the strength of the local magnetization. The anisotropic conductivity of up to three orders of magnitude can be achieved with a spatial critical temperature modulation of 5% of T c. Induced anisotropic properties in the F/S and F/S/F hybrids have a potential for future application in switching and nonvolatile memory elements operating at low temperatures. |
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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, N.Y. |
Editor |
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Language |
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Wos |
000289855700150 |
Publication Date |
2010-10-01 |
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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 |
1557-1939;1557-1947; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.18 |
Times cited |
2 |
Open Access |
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Notes |
; This work as well as the use of the Center for Nanoscale Materials and the Electron Microscopy Center at Argonne National Laboratory were supported by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. This work was also supported by the Ministry of Education, Agency for Structural Funds of the European Union, Research and Development Program, under agreement 262 401 200 19. M.V.M. and F. M. P. acknowledge support from the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, the JSPS/ESF-NES program, the ESF-AQDJJ network, and the Vlaanderen-USA bilateral program. ; |
Approved |
Most recent IF: 1.18; 2011 IF: 0.650 |
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Call Number |
UA @ lucian @ c:irua:89930 |
Serial |
130 |
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| Permanent link to this record |
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Author |
Abakumov, A.M.; Batuk, D.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Waschowski, F.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V. |
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Title |
Antiferroelectric (Pb,Bi)1-xFe1+xO3-y perovskites modulated by crystallographic shear planes |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
23 |
Issue |
2 |
Pages |
255-265 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We demonstrate for the first time a possibility to vary the anion content in perovskites over a wide range through a long-range-ordered arrangement of crystallographic shear (CS) planes. Anion-deficient perovskites (Pb,Bi)1−xFe1+xO3−y with incommensurately modulated structures were prepared as single phases in the compositional range from Pb0.857Bi0.094Fe1.049O2.572 to Pb0.409Bi0.567Fe1.025O2.796. Using a combination of electron diffraction and high-resolution scanning transmission electron microscopy, we constructed a superspace model describing a periodic arrangement of the CS planes. The model was verified by refinement of the Pb0.64Bi0.32Fe1.04O2.675 crystal structure from neutron powder diffraction data ((3 + 1)D S.G. X2/m(α0γ), X = [1/2,1/2,1/2,1/2], a = 3.9082(1) Å, b = 3.90333(8) Å, c = 4.0900(1) Å, β = 91.936(2)°, q = 0.05013(4)a* + 0.09170(3)c* at T = 700 K, RP = 0.036, RwP = 0.048). The (Pb,Bi)1−xFe1+xO3−y structures consist of perovskite blocks separated by CS planes confined to nearly the (509)p perovskite plane. Along the CS planes, the perovskite blocks are shifted with respect to each other over the 1/2[110]p vector that transforms the corner-sharing connectivity of the FeO6 octahedra in the perovskite framework to an edge-sharing connectivity of the FeO5 pyramids at the CS plane, thus reducing the oxygen content. Variation of the chemical composition in the (Pb,Bi)1−xFe1+xO3−y series occurs mainly because of a changing thickness of the perovskite block between the interfaces, that can be expressed through the components of the q vector as Pb6γ+2αBi1−7γ−αFe1+γ−αO3−3γ−α. The Pb, Bi, and Fe atoms are subjected to strong displacements occurring in antiparallel directions on both sides of the perovskite blocks, resulting in an antiferroelectric-type structure. This is corroborated by the temperature-, frequency-, and field-dependent complex permittivity measurements. Pb0.64Bi0.32Fe1.04O2.675 demonstrates a remarkably high resistivity >0.1 T Ω cm at room temperature and orders antiferromagnetically below TN = 608(10) K. |
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Washington, D.C. |
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Wos |
000286160800018 |
Publication Date |
2010-12-23 |
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ISSN |
0897-4756;1520-5002; |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.466 |
Times cited |
29 |
Open Access |
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Approved |
Most recent IF: 9.466; 2011 IF: 7.286 |
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Call Number |
UA @ lucian @ c:irua:88651 |
Serial |
136 |
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