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Records |
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Author |
Monico, L.; Janssens, K.; Hendriks, E.; Vanmeert, F.; van der Snickt, G.; Cotte, M.; Falkenberg, G.; Brunetti, B.G.; Miliani, C. |
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Title |
Evidence for degradation of the chrome yellows in Van Gogh's sunflowers : a study using noninvasive in situ methods and synchrotron-radiation-based x-ray techniques |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
| |
Volume  |
54 |
Issue |
47 |
Pages |
13923-13927 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
This paper presents firm evidence for the chemical alteration of chrome yellow pigments in Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam). Noninvasive in situ spectroscopic analysis at several spots on the painting, combined with synchrotron-radiation-based X-ray investigations of two microsamples, revealed the presence of different types of chrome yellow used by Van Gogh, including the lightfast PbCrO4 and the sulfur-rich PbCr1-xSxO4 (x approximate to 0.5) variety that is known for its high propensity to undergo photoinduced reduction. The products of this degradation process, i.e., Cr-III compounds, were found at the interface between the paint and the varnish. Selected locations of the painting with the highest risk of color modification by chemical deterioration of chrome yellow are identified, thus calling for careful monitoring in the future. |
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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 |
000367722500009 |
Publication Date |
2015-10-20 |
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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 |
1433-7851; 0570-0833 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
24 |
Open Access |
|
| |
Notes |
; We acknowledge financial support from the Italian MIUR project SICH-PRIN (2010329WPF_001) and BELSPO (Brussels) Project S2-ART (SD04A), GOA “SOLARPAINT” (Research Fund Antwerp University, BOF-2015), and FWO (Brussels) projects G.0C12.13, G.0704.08, G.01769.09. We thank ESRF (EC-1051, HG-26) and DESY (I-20120312 EC) for beamtime grants received. Noninvasive analysis of Sunflowers were supported by the EU FP7 programme CHARISMA (Grant 228330) and the Fund Inbev-Baillet Latour (Brussels). L.M. acknowledges financial support from the CNR Short Term Mobility Programme-2013. We thank Muriel Geldof, Luc Megens, Suzan de Groot (The Netherlands Cultural Heritage Agency, RCE), Chiara Grazia, David Buti (CNR-ISTM and SMAArt Centre), and the staff of the Van Gogh Museum for their collaboration. ; |
Approved |
Most recent IF: 11.994; 2015 IF: 11.261 |
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Call Number |
UA @ admin @ c:irua:131110 |
Serial |
5617 |
| Permanent link to this record |
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Author |
Vanmeert, F.; van der Snickt, G.; Janssens, K. |
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Title |
Plumbonacrite identified by X-ray powder diffraction tomography as a missing link during degradation of red lead in a Van Gogh painting |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
54 |
Issue |
12 |
Pages |
3607-3610 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Red lead, a semiconductor pigment used by artists since antiquity, is known to undergo several discoloration phenomena. These transformations are either described as darkening of the pigment caused by the formation of either plattnerite (β-PbO2) or galena (PbS) or as whitening by which red lead is converted into anglesite (PbSO4) or (hydro)cerussite (2 PbCO3⋅Pb(OH)2; PbCO3). X-ray powder diffraction tomography, a powerful analytical method that allows visualization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting. A very rare lead mineral, plumbonacrite (3 PbCO3⋅ Pb(OH)2⋅PbO), was revealed to be present. This is the first reported occurrence of this compound in a painting dating from before the mid 20th century. It constitutes the missing link between on the one hand the photoinduced reduction of red lead and on the other hand (hydro)cerussite, and thus sheds new light on the whitening of red lead. |
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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 |
000351178300008 |
Publication Date |
2015-02-20 |
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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 |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
24 |
Open Access |
|
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Notes |
; The authors acknowledge L. Van der Loeff and M. Leeuwestein (Kroller-Muller Museum) for providing the paint sample. We thank Dr. J. Jaroszewicz (WUT) for performing the CT measurements. This research was carried out at the light source PETRA III at DESY, a member of the Helmholtz Association (HGF). We thank Dr. G. Falkenberg and the members of his team for their assistance in using beam line P06. We acknowledge financial support from the University of Antwerp GOA projects “XANES meets EELS” and “SOLARPaint”, as well as from BELSPO (Brussels) Project S2-ART and FWO (Brussels) project “ESRF-Dubble”. ; |
Approved |
Most recent IF: 11.994; 2015 IF: 11.261 |
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Call Number |
UA @ admin @ c:irua:124620 |
Serial |
5774 |
| Permanent link to this record |
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Author |
Caretti, I.; Keulemans, M.; Verbruggen, S.W.; Lenaerts, S.; Van Doorslaer, S. |
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Title |
Light-induced processes in plasmonic Gold/TiO2 photocatalysts studied by electron paramagnetic resonance |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Topics in catalysis |
Abbreviated Journal |
Top Catal |
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Volume |
58 |
Issue |
12 |
Pages |
776-782 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
X-band and W-band continuous-wave (CW) electron paramagnetic resonance (EPR) was used to study in situ light-induced (LI) mechanisms in commercial P90 titania (90 % anatase/10 % rutile) compared to plasmon-enhanced Au-P90 photocatalyst. These materials were excited using UV and 532 nm visible light to generate different excitation states and distinguish pure charge separation from plasmon-assisted resonance processes. Up to nine different photoinduced species of trapped electrons and holes were identified. LI CW EPR of P90 is presented for the first time, showing a UV excitation response similar to the well-known mixed-phase P25 titania. It is shown that incorporation of Au nanoparticles in Au-P90 and formation of a Schottky junction affects the charge separation state of the catalyst under UV light. Moreover, Au impregnation activated P90 through plasmon hot electron injection under visible light excitation (plasmonic sensitization effect). In general, EPR proved to be crucial to determine the different photoexciation paths and reactions that regulate plasmonic photocatalysis. |
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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 |
000360011200008 |
Publication Date |
2015-08-03 |
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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 |
1022-5528 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.486 |
Times cited |
22 |
Open Access |
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Notes |
; IC and SVD acknowledge the Research Foundation-Flanders (FWO) for financial support (Grant G.0687.13). SV thanks FWO for financial support through a postdoctoral fellowship and MK acknowledges the agency for Innovation by Science and Technology in Flanders (IWT) for financial support (Ph.D. Grant). ; |
Approved |
Most recent IF: 2.486; 2015 IF: 2.365 |
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Call Number |
UA @ admin @ c:irua:127413 |
Serial |
5968 |
| Permanent link to this record |
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Author |
Ayalew, E.; Gebre, Y.; De Wael, K. |
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Title |
A survey of occupational exposure to inhalable wood dust among workers in small- and medium-scale wood-processing enterprises in Ethiopia |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
The annals of occupational hygiene |
Abbreviated Journal |
Ann Occup Hyg |
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Volume |
59 |
Issue |
2 |
Pages |
253-257 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A study of wood dust exposure in 20 small- and medium-scale wood-processing enterprises was performed in Ethiopia. Sampling was conducted daily from January to June, 2013 and a total of 360 samples from 113 workers were collected with Institute of Occupational Medicine (IOM) personal samplers. Eight-hour time-weighted average exposure to wood dust ranged from 0.24 to 23.3mg m−3 with a geometric mean (GM) of 6.82mg m−3 and a geometric standard deviation of 1.82. Although Ethiopia did not have any defined standard of Occupational Exposure Limit for wood dust exposure, 71% of the measurements exceeded the limit of 5mg m−3 set by the European Union (EU). Higher than the EU exposure limit was measured while workers perform sanding and sawing activities with a GM of 9.72 and 7.60mg m−3, respectively. In conclusion, wood workers in the small- and medium-scale enterprises are at a higher risk of developing different respiratory health problems with continuous exposure trends. |
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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 |
000352158700011 |
Publication Date |
2014-10-28 |
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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 |
0003-4878 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.71 |
Times cited |
4 |
Open Access |
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Notes |
; Eyasu Ayalew thanks the Addis Ababa University (Center for Environmental Sciences) for the personal grant for independent study. ; |
Approved |
Most recent IF: 1.71; 2015 IF: 2.101 |
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Call Number |
UA @ admin @ c:irua:119739 |
Serial |
5857 |
| Permanent link to this record |
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Author |
Bertrand, L.; Schoeeder, S.; Anglos, D.; Breese, M.B.H.; Janssens, K.; Moini, M.; Simon, A. |
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Title |
Mitigation strategies for radiation damage in the analysis of ancient materials |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Trends in analytical chemistry |
Abbreviated Journal |
Trac-Trend Anal Chem |
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Volume |
66 |
Issue |
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Pages |
128-145 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The study of materials in cultural heritage artifacts and micro-samples benefits from diagnostic techniques based on intense radiation sources, such as synchrotrons, ion-beam accelerators and lasers. While most of the corresponding techniques are classified as non-destructive, investigation with photons or charged particles entails a number of fundamental processes that may induce changes in materials. These changes depend on irradiation parameters, properties of materials and environmental factors. In some cases, radiation-induced damage may be detected by visual inspection. When it is not, irradiation may still lead to atomic and molecular changes resulting in immediate or delayed alteration and bias of future analyses. Here we review the effects of radiation reported on a variety of cultural heritage materials and describe the usual practice for assessing short-term and long-term effects. This review aims to raise awareness and encourage subsequent research activities to limit radiation side effects. |
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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 |
000352248200020 |
Publication Date |
2014-12-22 |
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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 |
0165-9936 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.442 |
Times cited |
35 |
Open Access |
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Notes |
; We wish to acknowledge the support of this initiative by the International Atomic Energy Agency. We gratefully thank Professor Manfred Schreiner of the Institute of Natural Sciences and Technology in the Arts (Akademie den bildenden Kunst, Vienna, Austria) for helpful discussions and insights on this work. We thank all colleagues who accepted to have their work reproduced in this review. IPANEMA at Synchrotron SOLEIL, the Hungarian Academy of Science and IESL-FORTH were supported within the Research Infrastructure program CHARISMA of the 7th Framework Programme of the EU (Grant Agreement no. 228330). MM's contribution is based upon work supported by the National Science Foundation under Grant numbers CHE 1241672 and CHE 1440849. We thank Chris McGlinchey and Lauren Klein (Museum of Modern Art, New York, USA) for their critical rereading of the manuscript. ; |
Approved |
Most recent IF: 8.442; 2015 IF: 6.472 |
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Call Number |
UA @ admin @ c:irua:124627 |
Serial |
5729 |
| Permanent link to this record |
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Author |
Van De Vijver, E.; Van Meirvenne, M.; Saey, T.; Delefortrie, S.; De Smedt, P.; De Pue, J.; Seuntjens, P. |
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Title |
Combining multi-receiver electromagnetic induction and stepped frequency ground penetrating radar for industrial site investigation |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
European journal of soil science |
Abbreviated Journal |
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Volume |
66 |
Issue |
4 |
Pages |
688-698 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
The soil at industrial sites is frequently characterized by very heterogeneous properties, which are often related to physical disturbance and contamination. A conventional approach to characterize the soil, with only a limited number of invasive observations, fails to capture the full extent of soil heterogeneity. Proximal soil sensing provides efficient tools to record spatially dense soil information. Nevertheless, because the output of most sensors is affected by more than one soil property, the simultaneous characterization of different soil properties requires the use of multiple sensors. Here, we apply multi-receiver electromagnetic induction (EMI) and stepped frequency ground penetrating radar (GPR) to survey a former gasworks site in a seaport area of Belgium. We used the EMI and GPR sensors in a motorized system to obtain densely sampled measurements of apparent electrical conductivity, apparent magnetic susceptibility and contrasts in relative dielectric permittivity. Our study shows that the sensors give detailed information on the variation in these electromagnetic soil properties. Interpretation of the variation in terms of the stratification of the soil was hampered by localized anthropogenic disturbances. However, the sensors provided complementary information that enabled the identification, discrimination and accurate location of several of these localized disturbances, including underground utility services such as electric cables, buried structures such as the remains of foundations and contamination by salts. Because these represent typical targets in industrial site investigation, we conclude that multi-receiver EMI and stepped frequency GPR provide a useful set of tools to expedite the investigation of industrial sites. |
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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 |
000357341900008 |
Publication Date |
2015-02-27 |
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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 |
1351-0754 |
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:127112 |
Serial |
7684 |
| Permanent link to this record |
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Author |
van Dyck, D.; Lobato, I.; Chen, F.-R.; Kisielowski, C. |
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Title |
Do you believe that atoms stay in place when you observe them in HREM? |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Micron |
Abbreviated Journal |
Micron |
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Volume |
68 |
Issue |
68 |
Pages |
158-163 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Recent advancements in aberration-corrected electron microscopy allow for an evaluation of unexpectedly large atom displacements beyond a resolution limit of similar to 0.5 angstrom, which are found to be dose-rate dependent in high resolution images. In this paper we outline a consistent description of the electron scattering process, which explains these unexpected phenomena. Our approach links thermal diffuse scattering to electron beam-induced object excitation and relaxation processes, which strongly contribute to the image formation process. The effect can provide an explanation for the well-known contrast mismatch (“Stobbs factor”) between image calculations and experiments. (C) 2014 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 |
Oxford |
Editor |
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Language |
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Wos |
000348016500023 |
Publication Date |
2014-09-16 |
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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 |
0968-4328; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.98 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.98; 2015 IF: 1.988 |
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Call Number |
c:irua:123802 |
Serial |
745 |
| Permanent link to this record |
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Author |
Kirilenko, D.A.; Dideykin, A.T.; Aleksenskiy, A.E.; Sitnikova, A.A.; Konnikov, S.G.; Vul', A.Y. |
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Title |
One-step synthesis of a suspended ultrathin graphene oxide film: Application in transmission electron microscopy |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Micron |
Abbreviated Journal |
Micron |
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Volume |
68 |
Issue |
68 |
Pages |
23-26 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Ultrathin graphene films find their use as advantageous support for nano- and biomaterials investigations. Thin film causes a very slight deterioration to measured signals, thus providing more details of the object's structure at nanoscale. The ultimate thinness of graphene works in the best way for this purpose. However, obtaining suspended thin film of a large-area, which is convenient for applications, is often a relatively complicated and time-consuming task. Here we present a one-step 1-min technique for synthesis of an extremely thin (about 1-2 nm) continuous film suspended over cells of a conventional copper grid (50-400 mu m mesh). This technique enables us to acquire a large-area film which is water-resistant, stable in organic solvents and can act as a support when studying nanoparticles or biomaterials. Moreover, the very mechanism of the film formation can be interesting from the point of view of other applications of ultrathin graphene oxide papers. (C) 2014 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 |
Oxford |
Editor |
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Language |
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Wos |
000348016500004 |
Publication Date |
2014-08-30 |
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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 |
0968-4328; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.98 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.98; 2015 IF: 1.988 |
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Call Number |
c:irua:123800 |
Serial |
2467 |
| Permanent link to this record |
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Author |
Adam, N.; Leroux, F.; Knapen, D.; Bals, S.; Blust, R. |
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Title |
The uptake and elimination of ZnO and CuO nanoparticles in Daphnia magna under chronic exposure scenarios |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Water research |
Abbreviated Journal |
Water Res |
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Volume |
68 |
Issue |
68 |
Pages |
249-261 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Veterinary physiology and biochemistry |
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Abstract |
In this study, the uptake and elimination of ZnO and CuO nanoparticles in Daphnia magna was tested. Daphnids were exposed during 10 days to sublethal concentrations of ZnO and CuO nanoparticles and corresponding metal salts (ZnCl2 and CuCl2.2H2O), after which they were transferred to unexposed medium for another 10 days. At different times during the exposure and none-exposure, the total and internal zinc or copper concentration of the daphnids was determined and the nanoparticles were localized in the organism using electron microscopy. The exposure concentrations were characterized by measuring the dissolved, nanoparticle and aggregated fraction in the medium. The results showed that the ZnO nanoparticles quickly dissolved after addition to the medium. Contrarily, only a small fraction (corresponding to the dissolved metal salt) of the CuO nanoparticles dissolved, while most of these nanoparticles formed large aggregates. Despite an initial increase in zinc and copper concentration during the first 48 hour to 5 day exposure, the body concentration reached a plateau level that was comparable for the ZnO nanoparticles and ZnCl2, but much higher for the CuO nanoparticles (with visible aggregates accumulating in the gut) than CuCl2.2H2O. During the remaining exposure and subsequent none-exposure phase, the zinc and copper concentration decreased fast to concentrations comparable with the unexposed daphnids. The results indicate that D. magna can regulate its internal zinc and copper concentration after exposure to ZnO and CuO nanoparticles, similar as after exposure to metal salts. The combined dissolution, accumulation and toxicity results confirm that the toxicity of ZnO and CuO nanoparticles is caused by the dissolved fraction. Keywords nano; zinc; copper; dissolution; aggregation; electron microscopy |
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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 |
Oxford |
Editor |
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Language |
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Wos |
000347756900022 |
Publication Date |
2014-10-14 |
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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 |
0043-1354; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.942 |
Times cited |
51 |
Open Access |
OpenAccess |
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Notes |
; The authors would like to thank Valentine Mubiana and Steven Joosen (Sphere, UA) for performing the ICP-MS and ICP-OES measurements and Prof. Dr. Gustaaf Van Tendeloo for making the collaboration between the EMAT and Sphere group possible. This study is part of the ENNSATOX-project, which was funded by the EU (NMP4-SL-2009-229244). The authors report no conflicts of interest. ; |
Approved |
Most recent IF: 6.942; 2015 IF: 5.528 |
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Call Number |
c:irua:119366 c:irua:119366 |
Serial |
3822 |
| Permanent link to this record |
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Author |
Batuk, D.; Batuk, M.; Abakumov, A.M.; Hadermann, J. |
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Title |
Synergy between transmission electron microscopy and powder diffraction : application to modulated structures |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Acta crystallographica: section B: structural science |
Abbreviated Journal |
Acta Crystallogr B |
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Volume |
71 |
Issue |
71 |
Pages |
127-143 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The crystal structure solution of modulated compounds is often very challenging, even using the well established methodology of single-crystal X-ray crystallography. This task becomes even more difficult for materials that cannot be prepared in a single-crystal form, so that only polycrystalline powders are available. This paper illustrates that the combined application of transmission electron microscopy (TEM) and powder diffraction is a possible solution to the problem. Using examples of anion-deficient perovskites modulated by periodic crystallographic shear planes, it is demonstrated what kind of local structural information can be obtained using various TEM techniques and how this information can be implemented in the crystal structure refinement against the powder diffraction data. The following TEM methods are discussed: electron diffraction (selected area electron diffraction, precession electron diffraction), imaging (conventional high-resolution TEM imaging, high-angle annular dark-field and annular bright-field scanning transmission electron microscopy) and state-of-the-art spectroscopic techniques (atomic resolution mapping using energy-dispersive X-ray analysis and electron energy loss spectroscopy). |
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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 |
Copenhagen |
Editor |
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Language |
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Wos |
000352166500002 |
Publication Date |
2015-04-01 |
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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 |
|
| |
ISSN |
2052-5206; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.032 |
Times cited |
11 |
Open Access |
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Notes |
Fwo G039211n |
Approved |
Most recent IF: 2.032; 2015 IF: NA |
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Call Number |
c:irua:124411 |
Serial |
3408 |
| Permanent link to this record |
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Author |
Saha, S.; Badhe, N.; Seuntjens, D.; Vlaeminck, S.E.; Biswas, R.; Nandy, T. |
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Title |
Effective carbon and nutrient treatment solutions for mixed domestic-industrial wastewater in India |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Water science and technology |
Abbreviated Journal |
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Volume |
72 |
Issue |
4 |
Pages |
651-657 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
The present study evaluates effectiveness of up-flow anaerobic sludge blanket (UASB) reactor followed by two post-anaerobic treatment options, namely free-surface, up-flow constructed wetland (FUP-CW) and oxygen-limited anaerobic nitrification/denitrification (OLAND) processes in treating sewage from the peri-urban areas in India receiving illegal industrial infiltrations. The UASB studies yielded robust results towards fluctuating strength of sewage and consistently removed 87-98% chemical oxygen demand (COD) at a hydraulic retention time of 1.5-2 d. The FUP-CW removed 68.5 +/- 13% COD, 68 +/- 3% NH4+-N, 38 +/- 5% PO43--P, 97.6 +/- 5% suspended particles and 97 +/- 13% fecal coliforms. Nutrient removal was found to be limiting in FUP-CW, especially in winter. Nitrogen removal in the OLAND process were 100 times higher than the FUP-CW process. Results show that UASB followed by FUP-CW can be an excellent, decentralized sewage treatment option, except during winter when nutrient removal is limited in FUP-CW. Hence, the study proposes bio-augmentation of FUP-CW with OLAND biomass for overall improvement in the performance of UASB followed by FUP-CW process. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000359387200019 |
Publication Date |
2015-08-06 |
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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 |
0273-1223; 1996-9732 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
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:127775 |
Serial |
7840 |
| Permanent link to this record |
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Author |
Amiri-Aref, M.; Raoof, J.B.; Kiekens, F.; De Wael, K. |
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Title |
Mixed hemi/ad-micelles coated magnetic nanoparticles for the entrapment of hemoglobin at the surface of a screen-printed carbon electrode and its direct electrochemistry and electrocatalysis |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Biosensors and bioelectronics |
Abbreviated Journal |
Biosens Bioelectron |
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Volume |
74 |
Issue |
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Pages |
518-525 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
An efficient procedure for the physical entrapment of proteins within a biocompatible matrix and their immobilization on electrode surfaces is of utmost importance in the fabrication of biosensors. In this work, the magnetic entrapment of hemoglobin (Hb) at the surface of a screen-printed carbon electrode (SPCE), through mixed hemi/ad-micelles (MHAM) array of positively charged surfactant supported iron oxide magnetic nanoparticles (Mag-NPs), is reported. The Hb/MHAM@Mag-NPs biocomposite is captured at SPCE by a super magnet (Hb/MHAM@Mag-NPs/SPCE). To gain insight in the configuration of the mixed hemi/ad-micelles of CTAB at Mag-NPs, zeta-potential measurements were performed. The entrapment of Hb at MHAM@Mag-NPs was confirmed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR). Direct electron transfer of the Hb intercalated into the composite film showed a pair of well-defined quasi-reversible redox peak at formal potential of −0.255 V vs. Ag/AgCl corresponding to heme Fe(III)/Fe(II) redox couple. It shows that the MHAM@Mag-NPs composite could increase the adsorption ability for Hb, thus provides a facile direct electron transfer between the Hb and the substrate. The proposed biosensor showed excellent electrocatalytic activity to the H2O2 reduction in the wide concentration range from 5.0 to 300.0 µM obtained by amperometric measurement. The MichaelisMenten constant (Km) value of Hb at the modified electrode is 55.4 µM, showing its high affinity. Magnetic entrapment offers a promising design for fast, convenient and effective immobilization of protein within a few minutes for determination of the target molecule in low sample volume at disposable cost-effective SPCE. |
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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 |
000360772800071 |
Publication Date |
2015-07-05 |
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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 |
0956-5663 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
7.78 |
Times cited |
14 |
Open Access |
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Notes |
; We are thankful for the BOF financial support from the University of Antwerp and Hercules financial support (SEM). ; |
Approved |
Most recent IF: 7.78; 2015 IF: 6.409 |
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Call Number |
UA @ admin @ c:irua:126535 |
Serial |
5731 |
| Permanent link to this record |
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Author |
Béché, A.; Winkler, R.; Plank, H.; Hofer, F.; Verbeeck, J. |
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Title |
Focused electron beam induced deposition as a tool to create electron vortices |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Micron |
Abbreviated Journal |
Micron |
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Volume |
80 |
Issue |
80 |
Pages |
34-38 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Focused electron beam induced deposition (FEBID) is a microscopic technique that allows geometrically controlled material deposition with very high spatial resolution. This technique was used to create a spiral aperture capable of generating electron vortex beams in a transmission electron microscope (TEM). The vortex was then fully characterized using different TEM techniques, estimating the average orbital angular momentum to be approximately 0.8variant Planck's over 2pi per electron with almost 60% of the beam ending up in the l=1 state. |
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Address |
EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium |
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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 |
English |
Wos |
000366770100006 |
Publication Date |
2015-09-12 |
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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 |
0968-4328; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.98 |
Times cited |
21 |
Open Access |
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Notes |
A.B and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX. J.V., R.W., H.P. and F.H. acknowledge financial support from the European Union under the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). R.W and H.P also acknowledge financial support by the COST action CELINA (Nr. CM1301) and the EUROSTARS project TRIPLE-S (Nr. E!8213). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government.; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 1.98; 2015 IF: 1.988 |
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Call Number |
c:irua:129203 c:irua:129203UA @ admin @ c:irua:129203 |
Serial |
3946 |
| Permanent link to this record |
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Author |
Wang, X.; Kustov, S.; Li, K.; Schryvers, D.; Verlinden, B.; Van Humbeeck, J. |
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Title |
Effect of nanoprecipitates on the transformation behavior and functional properties of a Ti50.8 at.% Ni alloy with micron-sized grains |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
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Volume |
82 |
Issue |
82 |
Pages |
224-233 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
In order to take advantage of both grain refinement and precipitation hardening effects, nanoscaled Ni4Ti3 precipitates are introduced in a Ti50.8 at.% Ni alloy with micron-sized grains (average grain size of 1.7 μm). Calorimetry, electrical resistance studies and thermomechanical tests were employed to study the transformation behavior and functional properties in relation to the obtained microstructure. A significant suppression of martensite transformation by the obtained microstructure is observed. The thermomechanical tests show that the advantageous properties of both grain refinement and precipitation hardening are combined in the developed materials, resulting in superior shape memory characteristics and stability of pseudoelasticity. It is concluded that introducing nanoscaled Ni4Ti3 precipitates into small grains is a new approach to improve the functional properties of NiTi shape memory alloys. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000347017800021 |
Publication Date |
2014-10-04 |
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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 |
1359-6454; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.301 |
Times cited |
51 |
Open Access |
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Notes |
Fwo |
Approved |
Most recent IF: 5.301; 2015 IF: 4.465 |
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Call Number |
c:irua:120469 |
Serial |
824 |
| Permanent link to this record |
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Author |
Cagno, S.; Cosyns, P.; Ceglia, A.; Nys, K.; Janssens, K. |
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Title |
The use of vitrum obsianum in the Roman Empire: some new insights and future prospects |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Periodico di mineralogia |
Abbreviated Journal |
Period Mineral |
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Volume |
84 |
Issue |
3a |
Pages |
465-482 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The research on the use of obsidian in the Mediterranean is extensive but concerns almost exclusively volcanic glass from prehistoric and Bronze Age contexts. The consumption of obsidian during the Roman imperial period, however, has only occasionally received attention. Never a comprehensive account on what the Romans made in vitrum obsianum has been set up, nor have the sources exploited by them been examined. This paper provides a concise overview of the current knowledge on obsidian during the Roman imperial period and offers an introductory outline on potential research. The ancient writers inform us about the use of volcanic glass to create exclusive vessels, gemstones, mirrors and sculpture, but also about the creation of black appearing man-made glass initiated as a cheap and easier workable substitute of obsidian. The archaeological data on the other hand propose a more complex story with the occurrence of obsidian chunks in early Roman secondary glass workshops, and the bulky use of obsidian in late Antiquity to produce tesserae for the creation of wall and vault mosaics. Because it is extremely difficult to visually distinguish natural obsidian from man-made glass imitations we present in this paper data collected by means of non-destructive chemico-physical analyses SEM-EDX, portable X-ray fluorescence (p-XRF) and Raman spectroscopy to easily distinguish man-made glass from natural obsidian. In particular the use of portable instruments makes possible in situ analysis of objects in archaeological depots or museum collections to help defining distribution networks to better understand the shifting consumption patterns in Antiquity. |
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Place of Publication |
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Wos |
000365632500007 |
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 |
0369-8963 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
0.883 |
Times cited |
2 |
Open Access |
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Notes |
; Our sincere gratitude goes to Cecile Evers and Natacha Masar to have granted permission for studying and analysing various obsidian artefacts within the collections of the Royal Museums of Art and History, Brussels (Belgium). We are also very grateful to Roald Doctor, Daniele Foy and Laudine Robin, respectively for having provided the material from Carthage, for the Sidi Jdidi tessera and Lyon. Our appreciation also goes to Ian Freestone and Andrew Meek respectively for having worked out and provided the internal report on the horse foreleg in the British Museum. Finally we wish to thank Jennifer Price, Maria Grazia Diani respectively for the information on the Stanwick fragment and the piece in the Pogliaghi-Varesse collection. This research was supported by the Hercules Foundation (Brussels) with the grant AUHA09004 and FWO (Brussels, Belgium) projects no. G.0C12.13 and G.01769.09 and partly by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. ; |
Approved |
Most recent IF: 0.883; 2015 IF: 0.464 |
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Call Number |
UA @ admin @ c:irua:130244 |
Serial |
5876 |
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Author |
Lu, Y.-G.; Turner, S.; Ekimov, E.A.; Verbeeck, J.; Van Tendeloo, G. |
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Title |
Boron-rich inclusions and boron distribution in HPHT polycrystalline superconducting diamond |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
86 |
Issue |
86 |
Pages |
156-162 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Polycrystalline boron-doped superconducting diamond, synthesized at high pressure and high temperature (HPHT) via a reaction of a single piece of crystalline boron with monolithic graphite, has been investigated by analytical transmission electron microscopy. The local boron distribution and boron environment have been studied by a combination of (scanning) transmission electron microscopy ((S)TEM) and spatially resolved electron energy-loss spectroscopy (EELS). High resolution TEM imaging and EELS elemental mapping have established, for the first time, the presence of largely crystalline diamond-diamond grain boundaries within the material and have evidenced the presence of substitutional boron dopants within individual diamond grains. Confirmation of the presence of substitutional B dopants has been obtained through comparison of acquired boron K-edge EELS fine structures with known references. This confirmation is important to understand the origin of superconductivity in polycrystalline B-doped diamond. In addition to the substitutional boron doping, boron-rich inclusions and triple-points, both amorphous and crystalline, with chemical compositions close to boron carbide B4C, are evidenced. (C) 2015 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 |
Oxford |
Editor |
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Language |
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Wos |
000352922700019 |
Publication Date |
2015-01-22 |
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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 |
0008-6223; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.337 |
Times cited |
20 |
Open Access |
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Notes |
FWO; 246791 COUNTATOMS; 278510 VORTEX; Hercules ECASJO_; |
Approved |
Most recent IF: 6.337; 2015 IF: 6.196 |
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Call Number |
c:irua:125994UA @ admin @ c:irua:125994 |
Serial |
250 |
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Author |
Ranjbari, E.; Hadjmohammadi, M.R.; Kiekens, F.; De Wael, K. |
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Title |
Mixed hemi/ad-micelle sodium dodecyl sulfate-coated magnetic iron oxide nanoparticles for the efficient removal and trace determination of rhodamine-B and rhodamine-6G |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
87 |
Issue |
15 |
Pages |
7894-7901 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Mixed hemi/ad-micelle sodium dodecyl sulfate (SDS)-coated magnetic iron oxide nanoparticles (MHAMS-MIONPs) were used as an efficient adsorbent for both removal and preconcentration of two important carcinogenic xanthine dyes named rhodamine-B (RB) and rhodamine-6G (RG). To gain insight in the configuration of SDS molecules on the surface of MIONPs, zeta potential measurements were performed in different [SDS]/[MIONP] ratios. Zeta potential data indicated that mixed hemi/ad-micelle MHAM was formed in [SDS]/[MIONP] ratios over the range of 1.1 to 7.3. Parameters affecting the adsorption of dyes were optimized as removal efficiency by one variable at-a-time and response surface methodology; the obtained removal efficiencies were ∼100%. Adsorption kinetic and equilibrium studies, under the optimum condition (pH = 2; amount of MIONPs = 87.15 mg; [SDS]/[MIONP] ratio = 2.9), showed that adsorption of both dyes are based on the pseudo-second-order and the Langmuir isotherm models, respectively. The maximum adsorption capacities for RB and RG were 385 and 323 mg g1, respectively. MHAMS-MIONPs were also applied for extraction of RB and RG. Under optimum conditions (pH = 2; amount of damped MHAMS-MIONPs = 90 mg; eluent solvent volume = 2.6 mL of 3% acetic acid in acetonitrile), extraction recoveries for 0.5 mg L1 of RB and RG were 98% and 99%, with preconcentration factors of 327 and 330, respectively. Limit of detection obtained for rhodamine dyes were <0.7 ng mL1. Finally, MHAMS-MIONPs were successfully applied for both removal and trace determination of RB and RG in environmental and wastewater samples. |
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Wos |
000359277900056 |
Publication Date |
2015-07-08 |
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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 |
36 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 6.32; 2015 IF: 5.636 |
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Call Number |
UA @ admin @ c:irua:126583 |
Serial |
5730 |
| Permanent link to this record |
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Author |
Hai, G.-Q.; Peeters, F.M. |
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Title |
Hamiltonian of a many-electron system with single-electron and electron-pair states in a two-dimensional periodic potential |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
88 |
Issue |
88 |
Pages |
20 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Based on the metastable electron-pair energy band in a two-dimensional (2D) periodic potential obtained previously by Hai and Castelano [J. Phys.: Condens. Matter 26, 115502 (2014)], we present in this work a Hamiltonian of many electrons consisting of single electrons and electron pairs in the 2D system. The electron-pair states are metastable of energies higher than those of the single-electron states at low electron density. We assume two different scenarios for the single-electron band. When it is considered as the lowest conduction band of a crystal, we compare the obtained Hamiltonian with the phenomenological model Hamiltonian of a boson-fermion mixture proposed by Friedberg and Lee [Phys. Rev. B 40, 6745 (1989)]. Single-electron-electron-pair and electron-pair-electron-pair interaction terms appear in our Hamiltonian and the interaction potentials can be determined from the electron-electron Coulomb interactions. When we consider the single-electron band as the highest valence band of a crystal, we show that holes in this valence band are important for stabilization of the electron-pair states in the system. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000347776800005 |
Publication Date |
2015-01-10 |
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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 |
1434-6028;1434-6036; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.461 |
Times cited |
2 |
Open Access |
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Notes |
; This work was supported by FAPESP and CNPq (Brazil). ; |
Approved |
Most recent IF: 1.461; 2015 IF: 1.345 |
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Call Number |
c:irua:125317 |
Serial |
1406 |
| Permanent link to this record |
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Author |
Vasylenko, A.A.; Misko, V.R. |
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Title |
Nonlinear transport of the Wigner crystal in symmetric and asymmetric FET-like structures : nonlinear transport of the Wigner crystal on superfluid He-4 in quasi-one-dimensional channels with symmetric and asymmetric constrictions |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
88 |
Issue |
88 |
Pages |
105 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
When floating on a two-dimensional surface of superfluid He-4, electrons arrange themselves in two-dimensional crystalline structure known as Wigner crystal. In channels, the boundaries interfere the crystalline order and in case of very narrow channels one observes a quasi-one-dimensional (quasi-1D) Wigner crystal formed by just a few rows of electrons and, ultimately, one row in the “quantum wire” regime. Recently, the “quantum wire” regime was accessed experimentally [D.G. Rees, H. Totsuji, K. Kono, Phys. Rev. Lett. 108, 176801 (2012)] resulting in unusual transport phenomena such as, e.g., oscillations in the electron conductance. Using molecular dynamics simulations, we study the nonlinear transport of electrons in channels with various types of constrictions: single and multiple symmetric and asymmetric geometrical constrictions with varying width and length, and saddle-point-type potentials with varying gate voltage. In particular, we analyze the average particle velocity of the particles and the corresponding electron current versus the driving force or the gate voltage. We have revealed a significant difference in the dynamics for long and short constrictions: The oscillations of the average velocity of the particles for the systems with short constrictions exhibit a clear correlation with the transitions between the states with different numbers of rows of particles; on the other hand, for the systems with longer constrictions these oscillations are suppressed. The obtained results qualitatively agree with the experimental observations. Next, we propose a FET-like structure that consists of a channel with asymmetric constrictions. We show that applying a transverse bias results either in increase of the average particle velocity or in its suppression thus allowing a flexible control tool over the electron transport. The advantage of the asymmetric FET is that it does not have a gate and it allows an easy control of relatively large electron flow. Furthermore, the asymmetric device can be used for rectification of an ac-driven electron flow. Our results bring important insights into the dynamics of electrons floating on the surface of superfluid He-4 in channels with constrictions and allow the effective control over the electron transport. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000353065100002 |
Publication Date |
2015-04-16 |
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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 |
1434-6028;1434-6036; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.461 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 1.461; 2015 IF: 1.345 |
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Call Number |
c:irua:125997 |
Serial |
2359 |
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Author |
Berdiyorov, G.R.; Savel'ev, S.; Kusmartsev, F.V.; Peeters, F.M. |
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Title |
Effect of ordered array of magnetic dots on the dynamics of Josephson vortices in stacked SNS Josephson junctions under DC and AC current |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
88 |
Issue |
88 |
Pages |
286 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We use the anisotropic time-dependent Ginzburg-Landau theory to investigate the effect of a square array of out-of-plane magnetic dots on the dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting (SNS) Josephson junctions in the presence of external DC and AC currents. Periodic pinning due to the magnetic dots distorts the triangular lattice of fluxons and results in the appearance of commensurability features in the current-voltage characteristics of the system. For the larger values of the magnetization, additional peaks appear in the voltage-time characteristics of the system due to the creation and annihilation of vortex-antivortex pairs. Peculiar changes in the response of the system to the applied current is found resulting in a “superradiant” vortex-flow state at large current values, where a rectangular lattice of moving vortices is formed. Synchronizing the motion of fluxons by adding a small ac component to the biasing dc current is realized. However, we found that synchronization becomes difficult for large magnetization of the dots due to the formation of vortex-antivortex pairs. |
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Address |
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
| |
Language |
|
Wos |
000363960900002 |
Publication Date |
2015-10-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1434-6028 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.461 |
Times cited |
1 |
Open Access |
|
| |
Notes |
; This work was supported by EU Marie Curie (Project No. 253057). ; |
Approved |
Most recent IF: 1.461; 2015 IF: 1.345 |
| |
Call Number |
UA @ lucian @ c:irua:129509 |
Serial |
4166 |
| Permanent link to this record |
| |
|
| |
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Author |
Kuppens, T.; Van Dael, M.; Vanreppelen, K.; Thewys, T.; Yperman, J.; Carleer, R.; Schreurs, S.; Van Passel, S. |
| |
Title |
Techno-economic assessment of fast pyrolysis for the valorization of short rotation coppice cultivated for phytoextraction |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal Of Cleaner Production |
Abbreviated Journal |
J Clean Prod |
| |
Volume |
88 |
Issue |
|
Pages |
336-344 |
| |
Keywords |
A1 Journal article; Engineering Management (ENM) |
| |
Abstract |
The main barrier in the commercialization of phytoextraction as a sustainable alternative for remediating metal contaminated soils is its long time period, which can be countered by biomass valorization. From an environmental point of view, fast pyrolysis of the biomass is promising because its lower process temperature prevents metal volatilization. The remaining question is whether fast pyrolysis is also preferred from an economic point of view. Therefore, a techno-economic assessment of fast pyrolysis has been performed for a case study in the Campine region in Belgium. For this region, willow trees cultivated in short rotation have the right characteristics to serve as a phytoextracting crop. A techno-economic assessment requires by definition a multidisciplinary approach. The problem statement urges for a focus on the economic profitability from the viewpoint of an investor, including economic risk analysis. Fast pyrolysis seems more profitable than gasification. The profit is dependent on the scale of operation, the policy support (subsidies) and the oil yield. The economic risk can be reduced by increasing the scale of operation by means of complementing feedstocks, and by valorization of the char byproduct by subsequent processing to activated carbon. (C) 2014 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 |
|
Wos |
000347771100036 |
Publication Date |
2014-07-19 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0959-6526 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.715 |
Times cited |
36 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 5.715; 2015 IF: 3.844 |
| |
Call Number |
UA @ admin @ c:irua:127539 |
Serial |
6264 |
| Permanent link to this record |
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|
| |
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Author |
Maes, D.; Van Dael, M.; Vanheusden, B.; Goovaerts, L.; Reumerman, P.; Luzardo, N.M.; Van Passel, S. |
| |
Title |
Assessment of the sustainability guidelines of EU Renewable Energy Directive : the case of biorefineries |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Journal Of Cleaner Production |
Abbreviated Journal |
J Clean Prod |
| |
Volume |
88 |
Issue |
|
Pages |
61-70 |
| |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
| |
Abstract |
Sustainability guidelines can help to safeguard the sustainable use of biological materials. When these guidelines are legally prescribed, their influence on the economic viability of bioenergy, biofuel and bioliquid projects is increased substantially, through their impact on national subsidy regimes and international trade. One of the key examples is the European directive 2009/28/EC, or the Renewable Energy Directive (RED), and the related COM/2010/11 that integrate guidelines for calculating greenhouse gas impact for various bioenergy pathways. This paper looks further into the sustainability results when influenced by principal decisions that are legally open for debate. Therefore, a concise review is conducted of the legal state-of-the-art on whether a product is waste or not. The review pinpoints uncertainty, leading to four potential legal scenarios. The sustainability of a complex biorefinery is analysed for each scenario. The results show (i) a high sensitivity to the principal decisions on the nature of waste materials in the scenarios, and (ii) to the definition of boundaries between the processes. More detailed rules for the application of the RED guidelines are needed, and should be complemented with methods specifically targeting all relevant sustainability aspects, thereby enhancing the overall understanding of the sustainability of the process. (C) 2014 Elsevier Ltd. All rights reserved. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000347771100007 |
Publication Date |
2014-04-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0959-6526 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.715 |
Times cited |
25 |
Open Access |
|
| |
Notes |
; We would like to thank the editor and the anonymous referees for their helpful suggestions and insightful comments that have significantly improved the paper. The 'Energy Conversion Parks' (ECP) project is funded as Project nr IVA-VLANED-2.39 by the Interreg IVa-Flanders-Netherlands program from the European Fund for Regional Development that stimulates cross border projects. Also the Dutch Ministry of Economic Affairs, the Flemish Government, the Provinces of Noord-Brabant (NL), Zeeland (NL), Limburg (BE) and the partners (VITO, Avans University of Applied Sciences, Wageningen University and Research, Hasselt University, and Zeeland University of Applied Sciences) themselves are co-financing the project. Finally, we would like to express our gratitude towards the organization of the eighth Conference on Sustainable Development of Energy, Water and Environment systems in Dubrovnik (Croatia) for giving us the opportunity to present and thereby fine-tune our work. ; |
Approved |
Most recent IF: 5.715; 2015 IF: 3.844 |
| |
Call Number |
UA @ admin @ c:irua:127538 |
Serial |
6157 |
| Permanent link to this record |
| |
|
| |
|
Author |
Dantas, D.S.; Lima, A.R.P.; Chaves, A.; Almeida, C.A.S.; Farias, G.A.; Milošević, M.V. |
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Title |
Bound vortex states and exotic lattices in multicomponent Bose-Einstein condensates : the role of vortex-vortex interaction |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
| |
Volume |
91 |
Issue |
91 |
Pages |
023630 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We numerically study the vortex-vortex interaction in multicomponent homogeneous Bose-Einstein condensates within the realm of the Gross-Pitaevskii theory. We provide strong evidence that pairwise vortex interaction captures the underlying mechanisms which determine the geometric configuration of the vortices, such as different lattices in many-vortex states, as well as the bound vortex states with two (dimer) or three (trimer) vortices. Specifically, we discuss and apply our theoretical approach to investigate intra- and intercomponent vortex-vortex interactions in two- and three-component Bose-Einstein condensates, thereby shedding light on the formation of the exotic vortex configurations. These results correlate with current experimental efforts in multicomponent Bose-Einstein condensates and the understanding of the role of vortex interactions in multiband superconductors. |
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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 |
Lancaster, Pa |
Editor |
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| |
Language |
|
Wos |
000350255200014 |
Publication Date |
2015-02-27 |
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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 |
|
| |
ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.925 |
Times cited |
12 |
Open Access |
|
| |
Notes |
; This work was supported by the National Council for Scientific and Technological Development (CNPq-Brazil), the Coordination for the Improvement of Higher Education Personnel (CAPES-Brazil), Research Foundation Flanders (FWO), and the bilateral FWO-CNPq program between Flanders and Brazil. M.V.M. acknowledges support from the CAPES-PVE program (Grant No. BEX1392/11-5). ; |
Approved |
Most recent IF: 2.925; 2015 IF: 2.808 |
| |
Call Number |
c:irua:124907 |
Serial |
252 |
| Permanent link to this record |
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Author |
Grujić, M.M.; Tadic, M.Z.; Peeters, F.M. |
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Title |
Chiral properties of topological-state loops |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
91 |
Issue |
91 |
Pages |
245432 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The angular momentum quantization of chiral gapless modes confined to a circularly shaped interface between two different topological phases is investigated. By examining several different setups, we show analytically that the angular momentum of the topological modes exhibits a highly chiral behavior, and can be coupled to spin and/or valley degrees of freedom, reflecting the nature of the interface states. A simple general one-dimensional model, valid for arbitrarily shaped loops, is shown to predict the corresponding energies and the magnetic moments. These loops can be viewed as building blocks for artificial magnets with tunable and highly diverse properties. |
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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 |
Lancaster, Pa |
Editor |
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| |
Language |
|
Wos |
000356928200005 |
Publication Date |
2015-06-27 |
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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 |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
| |
Notes |
; This work was supported by the Ministry of Education, Science and Technological Development (Serbia), and the Fonds Wetenschappelijk Onderzoek (Belgium). ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
| |
Call Number |
c:irua:127039 |
Serial |
357 |
| Permanent link to this record |
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Author |
Shylau, A.A.; Badalyan, S.M.; Peeters, F.M.; Jauho, A.P. |
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Title |
Electron polarization function and plasmons in metallic armchair graphene nanoribbons |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
91 |
Issue |
91 |
Pages |
205444 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Plasmon excitations in metallic armchair graphene nanoribbons are investigated using the random phase approximation. An exact analytical expression for the polarization function of Dirac fermions is obtained, valid for arbitrary temperature and doping. We find that at finite temperatures, due to the phase space redistribution among inter-band and intra-band electronic transitions in the conduction and valence bands, the full polarization function becomes independent of temperature and position of the chemical potential. It is shown that for a given width of nanoribbon there exists a single plasmon mode whose energy dispersion is determined by the graphene's fine structure constant. In the case of two Coulomb-coupled nanoribbons, this plasmon splits into in-phase and out-of-phase plasmon modes with splitting energy determined by the inter-ribbon spacing. |
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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 |
000355315400007 |
Publication Date |
2015-05-29 |
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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 |
|
| |
ISSN |
1098-0121 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
| |
Notes |
; The Center for Nanostructured Graphene (CNG) is sponsored by the Danish National Research Foundation (DNRF58). The work at the University of Antwerp was supported by the Flemisch Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. S.M.B. gratefully acknowledges hospitality and support from the Department of Physics at the University of Missouri. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
| |
Call Number |
c:irua:126403 |
Serial |
984 |
| Permanent link to this record |
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Author |
Petrovic, M.D.; Peeters, F.M. |
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Title |
Fano resonances in the conductance of graphene nanoribbons with side gates |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
91 |
Issue |
91 |
Pages |
035444 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The control of side gates on the quantum electron transport in narrow graphene ribbons of different widths and edge types (armchair and zigzag) is investigated. The conductance exhibits Fano resonances with varying side gate potential. Resonant and antiresonant peaks in the conductance can be associated with the eigenstates of a closed system, and these peaks can be accurately fitted with a Fano line shape. The local density of states (LDOS) and the electron current show a specific behavior at these resonances, which depends on the ribbon edge type. In zigzag ribbons, transport is dominated by intervalley scattering, which is reflected in the transmission functions of individual modes. The side gates induce p-n interfaces near the edges at which the LDOS exhibits peaks. Near the resonance points, the electron current flows uniformly through the constriction, while near the antiresonances it creates vortices. In the armchair ribbons the LDOS spreads in areas of high potential, with current flowing near the edges. |
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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 |
|
Editor |
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Language |
|
Wos |
000351217900005 |
Publication Date |
2015-01-30 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
| |
Notes |
; This work was supported by the Methusalem programme of the Flemish government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
| |
Call Number |
c:irua:125422 |
Serial |
1172 |
| Permanent link to this record |
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Author |
Schoelz, J.K.; Xu, P.; Meunier, V.; Kumar, P.; Neek-Amal, M.; Thibado, P.M.; Peeters, F.M. |
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Title |
Graphene ripples as a realization of a two-dimensional Ising model : a scanning tunneling microscope study |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review: B: condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
91 |
Issue |
91 |
Pages |
045413 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Ripples in pristine freestanding graphene naturally orient themselves in an array that is alternately curved-up and curved-down; maintaining an average height of zero. Using scanning tunneling microscopy (STM) to apply a local force, the graphene sheet will reversibly rise and fall in height until the height reaches 60%-70% of its maximum at which point a sudden, permanent jump occurs. We successfully model the ripples as a spin-half Ising magnetic system, where the height of the graphene plays the role of the spin. The permanent jump in height, controlled by the tunneling current, is found to be equivalent to an antiferromagnetic-to-ferromagnetic phase transition. The thermal load underneath the STM tip alters the local tension and is identified as the responsible mechanism for the phase transition. Four universal critical exponents are measured from our STM data, and the model provides insight into the statistical role of graphene's unusual negative thermal expansion coefficient. |
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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 |
Lancaster, Pa |
Editor |
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| |
Language |
|
Wos |
000348762200011 |
Publication Date |
2015-01-12 |
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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 |
|
Series Issue |
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Edition |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
| |
Notes |
; This work was supported in part by Office of Naval Research (USA) under Grant No. N00014-10-1-0181 and National Science Foundation (USA) under Grant No. DMR-0855358. F. M. Peeters and M. Neek-Amal were supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
| |
Call Number |
c:irua:123866 |
Serial |
1377 |
| Permanent link to this record |
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Author |
Kuopanportti, P.; Orlova, N.V.; Milošević, M.V. |
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Title |
Ground-state multiquantum vortices in rotating two-species superfluids |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
| |
Volume |
91 |
Issue |
91 |
Pages |
043605 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We show numerically that a rotating, harmonically trapped mixture of two Bose-Einstein-condensed superfluids cancontrary to its single-species counterpartcontain a multiply quantized vortex in the ground state of the system. This giant vortex can occur without any accompanying single-quantum vortices, may either be coreless or have an empty core, and can be realized in a Rb87−K41 Bose-Einstein condensate. Our results not only provide a rare example of a stable, solitary multiquantum vortex but also reveal exotic physics stemming from the coexistence of multiple, compositionally distinct condensates in one system. |
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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 |
Lancaster, Pa |
Editor |
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| |
Language |
|
Wos |
000352255200005 |
Publication Date |
2015-04-07 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.925 |
Times cited |
25 |
Open Access |
|
| |
Notes |
; This work was supported by the Finnish Cultural Foundation, the Research Foundation – Flanders (FWO), and the Magnus Ehrnrooth Foundation. We thank E. Ruokokoski and T. P. Simula for valuable comments and discussions. ; |
Approved |
Most recent IF: 2.925; 2015 IF: 2.808 |
| |
Call Number |
c:irua:124906 |
Serial |
1388 |
| Permanent link to this record |
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Author |
Bacaksiz, C.; Sahin, H.; Ozaydin, H.D.; Horzum, S.; Senger, R.T.; Peeters, F.M. |
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Title |
Hexagonal A1N : dimensional-crossover-driven band-gap transition |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
91 |
Issue |
91 |
Pages |
085430 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Motivated by a recent experiment that reported the successful synthesis of hexagonal (h) AlN [Tsipas et al., Appl. Phys. Lett. 103, 251605 (2013)], we investigate structural, electronic, and vibrational properties of bulk, bilayer, and monolayer structures of h-AlN by using first-principles calculations. We show that the hexagonal phase of the bulk h-AlN is a stable direct-band-gap semiconductor. The calculated phonon spectrum displays a rigid-layer shear mode at 274 cm(-1) and an E-g mode at 703 cm(-1), which are observable by Raman measurements. In addition, single-layer h-AlN is an indirect-band-gap semiconductor with a nonmagnetic ground state. For the bilayer structure, AA'-type stacking is found to be the most favorable one, and interlayer interaction is strong. While N-layered h-AlN is an indirect-band-gap semiconductor for N = 1 – 9, we predict that thicker structures (N >= 10) have a direct band gap at the Gamma point. The number-of-layer-dependent band-gap transitions in h-AlN is interesting in that it is significantly different from the indirect-to-direct crossover obtained in the transition-metal dichalcogenides. |
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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 |
000350319200020 |
Publication Date |
2015-02-27 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
99 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). C.B. and R.T.S. acknowledge the support from TUBITAK Project No 114F397. H.S. is supported by a FWO Pegasus Long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
| |
Call Number |
c:irua:125416 |
Serial |
1421 |
| Permanent link to this record |
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Author |
Van Boxem, R.; Partoens, B.; Verbeeck, J. |
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Title |
Inelastic electron-vortex-beam scattering |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
| |
Volume |
91 |
Issue |
91 |
Pages |
032703 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| |
Abstract |
Recent theoretical and experimental developments in the field of electron-vortex-beam physics have raised questions about what exactly this novelty in the field of electron microscopy (and other fields, such as particle physics) really provides. An important part of the answer to these questions lies in scattering theory. The present investigation explores various aspects of inelastic quantum scattering theory for cylindrically symmetric beams with orbital angular momentum. The model system of Coulomb scattering on a hydrogen atom provides the setting to address various open questions: How is momentum transferred? Do vortex beams selectively excite atoms, and how can one employ vortex beams to detect magnetic transitions? The analytical approach presented here provides answers to these questions. OAM transfer is possible, but not through selective excitation; rather, by pre- and postselection one can filter out the relevant contributions to a specific signal. |
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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 |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000351035000004 |
Publication Date |
2015-03-16 |
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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 |
1050-2947;1094-1622; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.925 |
Times cited |
31 |
Open Access |
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Notes |
Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 2.925; 2015 IF: 2.808 |
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Call Number |
c:irua:123925 c:irua:123925UA @ admin @ c:irua:123925 |
Serial |
1607 |
| Permanent link to this record |
