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Records |
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Author |
van der Snickt, G.; Dik, J.; Cotte, M.; Janssens, K.; Jaroszewicz, J.; de Nolf, W.; Groenewegen, J.; van der Loeff, L. |
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Title |
Characterization of a degraded cadmium yellow (CdS) pigment in an oil painting by means of synchrotron radiation based X-ray techniques |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
81 |
Issue |
7 |
Pages |
2600-2610 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
On several paintings of James Ensor (1860−1949), a gradual fading of originally bright yellow areas, painted with the pigment cadmium yellow (CdS), is observed. Additionally, in some areas exposed to light, the formation of small white-colored globules on top of the original paint surface is observed. In this paper the chemical transformation leading to the color change and to the formation of the globules is elucidated. Microscopic X-ray absorption near-edge spectroscopy (ì-XANES) experiments show that sulfur, originally present in sulfidic form (S2−), is oxidized during the transformation to the sulfate form (S6+). Upon formation (at or immediately below the surface), the highly soluble cadmium sulfate is assumed to be transported to the surface in solution and reprecipitates there, forming the whitish globules. The presence of cadmium sulfate (CdSO4·2H2O) and ammonium cadmium sulfate [(NH4)2Cd(SO4)2] at the surface is confirmed by microscopic X-ray diffraction measurements, where the latter salt is suspected to result from a secondary reaction of cadmium sulfate with ammonia. Measurements performed on cross sections reveal that the oxidation front has penetrated into the yellow paint down to ca. 1−2 ìm. The morphology and elemental distribution of the paint and degradation product were examined by means of scanning electron microscopy equipped with an energy-dispersive spectrometer (SEM-EDS) and synchrotron radiation based micro-X-ray fluorescence spectrometry (SR ì-XRF). In addition, ultraviolet-induced visible fluorescence photography (UIVFP) revealed itself to be a straightforward technique for documenting the occurrence of this specific kind of degradation on a macroscale by painting conservators. |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000264759400025 |
Publication Date |
2009-03-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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 |
91 |
Open Access |
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Notes |
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Approved  |
Most recent IF: 6.32; 2009 IF: 5.214 |
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Call Number |
UA @ admin @ c:irua:76415 |
Serial |
5501 |
| Permanent link to this record |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Verbeeck, J.; Tian, H.; Tan, H.; Dik, J.; Radepont, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| |
Volume |
83 |
Issue |
4 |
Pages |
1214-1223 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000287176900011 |
Publication Date |
2011-02-14 |
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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 |
0003-2700;1520-6882; |
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 |
113 |
Open Access |
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Notes |
Iuap; Fwo |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
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Call Number |
UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794 |
Serial |
632 |
| Permanent link to this record |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Dik, J.; Radepont, M.; Hendriks, E.; Geldof, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 2 : original paint layer samples |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
83 |
Issue |
4 |
Pages |
1224-1231 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The darkening of the original yellow areas painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is a phenomenon widely observed on several paintings by Vincent van Gogh, such as the famous different versions of Sunflowers. During our previous investigations on artificially aged model samples of lead chromate, we established for the first time that darkening of chrome yellow is caused by reduction of PbCrO4 to Cr2O3·2H2O (viridian green), likely accompanied by the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide]. In the second part of this work, in order to demonstrate that this reduction phenomenon effectively takes place in real paintings, we study original paint samples from two paintings of V. van Gogh. As with the model samples, in view of the thin superficial alteration layers that are present, high lateral resolution spectroscopic methods that make use of synchrotron radiation (SR), such as microscopic X-ray absorption near edge (μ-XANES) and X-ray fluorescence spectrometry (μ-XRF) were employed. Additionally, μ-Raman and mid-FTIR analyses were carried out to completely characterize the samples. On both paint microsamples, the local presence of reduced Cr was demonstrated by means of μ-XANES point measurements. The presence of Cr(III) was revealed in specific areas, in some cases correlated to the presence of Ba(sulfate) and/or to that of aluminum silicate compounds. |
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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 |
000287176900012 |
Publication Date |
2011-02-14 |
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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 |
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 |
84 |
Open Access |
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Notes |
; This research was funded by grants from ESRF (experiment EC-504) and by HASYLAB (experiments 11-20080130 EC and 11-20070157 EC) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Van Gogh Museum, Amsterdam, is acknowledged for their agreeable cooperation and for the authorization to publish the images of the paintings in this article. L.M. was financially supported by the Erasmus Placement in the framework of Lifelong Learning Programme (A.Y. 2009-2010). The EU Community's FP7 Research Infrastructures program under the CHARISMA Project (Grant Agreement 228330) is also acknowledged. ; |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
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Call Number |
UA @ admin @ c:irua:88795 |
Serial |
5571 |
| Permanent link to this record |
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Author |
Rouchon, V.; Duranton, M.; Burgaud, C.; Pellizzi, E.; Lavédrine, B.; Janssens, K.; de Nolf, W.; Nuyts, G.; Vanmeert, F.; Hellemans, K. |
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Title |
Room-temperature study of iron gall ink impregnated paper degradation under various oxygen and humidity conditions : time-dependent monitoring by viscosity and X-ray absorption near-edge spectrometry measurements |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
83 |
Issue |
7 |
Pages |
2589-2597 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Many western manuscripts were written using iron gall inks. These inks can damage the paper via two major mechanisms: (a) acid hydrolysis, enhanced by humidity, and (b) oxidative depolymerization provoked by the presence of oxygen and free iron(II) ions. The degradation of unsized Whatman paper impregnated with different combinations of iron sulfate, gallic acid, and gum arabic was studied at room temperature in order to assess the relative importance of each mechanism. The samples were stored in various environments including a dry and/or an oxygen-free atmosphere. The cellulose depolymerization was monitored by viscometry and related to changes in the oxidation state of iron, determined by X-ray absorption near-edge spectrometry. The results indicate that residual amounts of oxygen (less than 0.1%) promote cellulose depolymerization, whereas the level of relative humidity has no impact. The cellulose depolymerization also appears closely correlated to oxidative mechanisms. Regarding the oxidation of iron, it only occurs in the simultaneous presence of oxygen and moisture, suggesting the occurrence of rustlike oxidative mechanisms. Finally, the presence of gallic acid has a strong influence, which is only partially explained by its capacity to reduce iron(III) to iron(II). |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000288887700028 |
Publication Date |
2011-03-04 |
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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 |
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 |
28 |
Open Access |
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Notes |
; This research was supported by the French Ministry of Culture within the National Program of Research (“La conservation des manuscrits: etude du vieillissement naturel de papiers impregnes d'encres ferrogalliques”). It was funded by grants from HASYLAB (experiments I-20090280 EC and II-20060245 EC) and SOLEIL (proposals 20060396 and 20080761) and was supported by the Interuniversity Attraction Poles Programme Belgian Science Policy (1UAP V1/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects nos. G.0689.06, G.0704.08 and G017909N. We are thankful to Dr. Dominique Thaudiere, Dr. Solenn Reguer, Dr. Andrea Somogyi, Dr. Karen Appel, Dr. Manuela Borchert, and Dr. Gerald Falkenberg for their assistance and help during the experiments performed at SOLEIL beamline “DIFFABS” and at HASYLAB Beam line “L” respectively. ; |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
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Call Number |
UA @ admin @ c:irua:89593 |
Serial |
5822 |
| Permanent link to this record |
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Author |
van der Snickt, G.; Janssens, K.; Dik, J.; de Nolf, W.; Vanmeert, F.; Jaroszewicz, J.; Cotte, M.; Falkenberg, G.; Van der Loeff, L. |
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Title |
Combined use of synchrotron radiation based micro-X-ray fluorescence, micro-X-ray diffraction, micro-X-ray absorption near-edge, and micro-fourier transform infrared spectroscopies for revealing an alternative degradation pathway of the pigment cadmium yellow in a painting by Van Gogh |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
84 |
Issue |
23 |
Pages |
10221-10228 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Over the past years a number of studies have described the instability of the pigment cadmium yellow (CdS). In a previous paper we have shown how cadmium sulfide on paintings by James Ensor oxidizes to CdSO4 center dot H2O. The degradation process gives rise to the fading of the bright yellow color and the formation of disfiguring white crystals that are present on the paint surface in approximately 50 mu m sized globular agglomerations. Here, we study cadmium yellow in the painting “Flowers in a blue vase” by Vincent van Gogh. This painting differs from the Ensor case in the fact that (a) a varnish was superimposed onto the degraded paint surface and (b) the CdS paint area is entirely covered with an opaque crust. The latter obscures the yellow color completely and thus presents a seemingly more advanced state of degradation. Analysis of a cross-sectioned and a crushed sample by combining scanning microscopic X-ray diffraction (mu-XRD), microscopic X-ray absorption near-edge spectroscopy (mu-XANES), microscopic X-ray fluorescence (mu-XRF) based chemical state mapping and scanning microscopic Fourier transform infrared (mu-FT-IR) spectrometry allowed unravelling the complex alteration pathway. Although no crystalline CdSO4 compounds were identified on the Van Gogh paint samples, we conclude that the observed degradation was initially caused by oxidation of the original CdS pigment, similar as for the previous Ensor case. However, due to the presence of an overlying varnish containing lead-based driers and oxalate ions, secondary reactions took place. In particular, it appears that upon the photoinduced oxidation of its sulfidic counterion, the Cd2+ ions reprecipitated at the paint/varnish interface after having formed a complex with oxalate ions that themselves are considered to be degradation products of the resin and/or oil in the varnish. The SO42- anions, for their part, found a suitable reaction partner in Pb2+ ions stemming from a dissolved lead-based siccative that was added to the varnish to promote its drying. The resulting opaque anglesite compound in the varnish, in combination with the underlying CdC2O4 layer at the paint/varnish interface, account for the orange-gray crust that is disfiguring the painting on a macroscopic level. In this way, the results presented in this paper demonstrate how, through a judicious combined use of several microanalytical methods with speciation capabilities, many new insights can be obtained from two minute, but highly complex and heterogeneous paint samples. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000311815300013 |
Publication Date |
2012-08-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
59 |
Open Access |
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Notes |
; This research was supported by BELSPO via the Interuniversity Attraction Poles Programme (IUAP VI/16) and the S2-ART project (SD/RI/04A) and funded by Grants from the ESRF (EC-442) and PETRA-III (I-20120312 EC). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Kroller-Muller Museum and painting conservators Margje Leeuwestein and Esther Van Duijn are acknowledged for this pleasant cooperation and the authorization for the publication of the images in this article. ; |
Approved |
Most recent IF: 6.32; 2012 IF: 5.695 |
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Call Number |
UA @ admin @ c:irua:105971 |
Serial |
5526 |
| Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Miliani, C.; Brunetti, B.G.; Vagnini, M.; Vanmeert, F.; Falkenberg, G.; Abakumov, A.; Lu, Y.; Tian, H.; Verbeeck, J.; Radepont, M.; Cotte, M.; Hendriks, E.; Geldof, M.; van der Loeff, L.; Salvant, J.; Menu, M.; |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 3 : synthesis, characterization, and detection of different crystal forms of the chrome yellow pigment |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
85 |
Issue |
2 |
Pages |
860-867 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The painter, Vincent van Gogh, and some of his contemporaries frequently made use of the pigment chrome yellow that is known to show a tendency toward darkening. This pigment may correspond to various chemical compounds such as PbCrO4 and PbCr1-xSxO4, that may each be present in various crystallographic forms with different tendencies toward degradation. Investigations by X-ray diffraction (XRD), mid-Fourier Transform infrared (FTIR), and Raman instruments (benchtop and portable) and synchrotron radiation-based micro-XRD and X-ray absorption near edge structure spectroscopy performed on oil-paint models, prepared with in-house synthesized PbCrO4 and PbCr1-xSxO4, permitted us to characterize the spectroscopic features of the various forms. On the basis of these results, an extended study has been carried out on historic paint tubes and on embedded paint microsamples taken from yellow-orange/pale yellow areas of 12 Van Gogh paintings, demonstrating that Van Gogh effectively made use of different chrome yellow types. This conclusion was also confirmed by in situ mid-FTIR investigations on Van Goghs Portrait of Gauguin (Van Gogh Museum, Amsterdam). |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000313668400031 |
Publication Date |
2012-10-10 |
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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 |
0003-2700;1520-6882; |
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 |
79 |
Open Access |
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Notes |
Goa; Fwo |
Approved |
Most recent IF: 6.32; 2013 IF: 5.825 |
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Call Number |
UA @ lucian @ c:irua:108707UA @ admin @ c:irua:108707 |
Serial |
631 |
| Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Miliani, C.; van der Snickt, G.; Brunetti, B.G.; Guidi, M.C.; Radepont, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 4 : artificial aging of model samples of co-precipitates of lead chromate and lead sulfate |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
85 |
Issue |
2 |
Pages |
860-867 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Previous investigations about the darkening of chrome yellow pigments revealed that this form of alteration is attributable to a reduction of the original Cr(VI) to Cr(III), and that the presence of sulfur-containing compounds, most often sulfates, plays a key role during this process. We recently demonstrated that different crystal forms of chrome yellow pigments (PbCrO4 and PbCr1xSxO4) are present in paintings by Vincent van Gogh. In the present work, we show how both the chemical composition and the crystalline structure of lead chromate-based pigments influence their stability. For this purpose, oil model samples made with in-house synthesized powders of PbCrO4 and PbCr1xSxO4 were artificially aged and characterized. We observed a profound darkening only for those paint models made with PbCr1xSxO4, rich in SO42 (x ≥ 0.4), and orthorhombic phases (>30 wt %). Cr and S K-edge micro X-ray absorption near edge structure investigations revealed in an unequivocal manner the formation of up to about 60% of Cr(III)-species in the outer layer of the most altered samples; conversely, independent of the paint models chemical composition, no change in the S-oxidation state was observed. Analyses employing UVvisible diffuse reflectance and Fourier transform infrared spectroscopy were performed on unaged and aged model samples in order to obtain additional information on the physicochemical changes induced by the aging treatment. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000313668400032 |
Publication Date |
2012-10-10 |
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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 |
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 |
49 |
Open Access |
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Notes |
; This research was supported by grants from ESRF (experiment EC-799), the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16), and the BELSPO-SDD S2-ART (SD/RI/04) project. The text also presents results from GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects G.0704.08 and G.01769.09. The EU FP7 programme CHARISMA (Grant Agreement 228330) and MIUR (PRIN08, Materiali e sistemi innovativi per la conservazione dell'arte contemporanea 2008 FFXXN9) are also acknowledged. ; |
Approved |
Most recent IF: 6.32; 2013 IF: 5.825 |
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Call Number |
UA @ admin @ c:irua:110471 |
Serial |
5569 |
| Permanent link to this record |
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Author |
Monico, L.; Janssens, K.; Vanmeert, F.; Cotte, M.; Brunetti, B.G.; van der Snickt, G.; Leeuwestein, M.; Plisson, J.S.; Menu, M.; Miliani, C. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : part 5 : effects of nonoriginal surface coatings into the nature and distribution of chromium and sulfur species in chrome yellow paints |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
86 |
Issue |
21 |
Pages |
10804-10811 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The darkening of lead chromate yellow pigments, caused by a reduction of the chromate ions to Cr(III) compounds, is known to affect the appearance of several paintings by Vincent van Gogh. In previous papers of this series, we demonstrated that the darkening is activated by light and depends on the chemical composition and crystalline structure of the pigments. In this work, the results of Part 2 are extended and complemented with a new study aimed at deepening the knowledge of the nature and distribution of Cr and S species at the interface between the chrome yellow paint and the nonoriginal coating layer. For this purpose, three microsamples from two varnished paintings by Van Gogh and a waxed low relief by Gauguin (all originally uncoated) have been examined. Because nonoriginal coatings are often present in artwork by Van Gogh and contemporaries, the understanding of whether or not their application has influenced the morphological and/or physicochemical properties of the chrome yellow paint underneath is relevant in view of the conservation of these masterpieces. In all the samples studied, microscopic X-ray fluorescence (mu-XRF) and X-ray absorption near edge structure (mu-XANES) investigations showed that Cr(III)-based alteration products are present in the form of grains inside the coating (generally enriched of S species) and also homogeneously widespread at the paint surface. The distribution of Cr(III) species may be explained by the mechanical friction caused by the coating application by brush that picked up and redistributed the superficial Cr compounds, likely already present in the reduced state as result of the photodegradation process. The analysis of the XANES profiles allowed us to obtain new insights into the nature of the Cr(III) alteration products, that were identified as sulfate-, oxide-, organo-metal-, and chloride-based compounds. Building upon the knowledge acquired through the examination of original paint samples and from the investigation of aged model paints in the last Part 4 paper, in this study we aim to characterize a possible relation between the chemical composition of the coating and the chrome yellow degradation pathways by studying photochemically aged model samples covered with a dammar varnish contaminated with sulfide and sulfate salts. Cr speciation results did not show any evidence of the active role of the varnish and added S species on the reduction process of chrome yellows. |
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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 |
000344510200043 |
Publication Date |
2014-10-10 |
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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 |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.32 |
Times cited |
25 |
Open Access |
|
| |
Notes |
; This research was supported by the Italian projects PRIN (SICH) and PON (ITACHA). The text also presents results from Interuniversity Attraction Poles Programme Belgian Science Policy (S2-ART project S4DA), GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. ESRF is acknowledged for the grants received (experiments EC-799 and EC-1051). L.M. acknowledges the CNR for the financial support received in the framework of the Short Term Mobility Programme 2013. Thanks are expressed to Ella Hendriks (Van Gogh Museum, Amsterdam) and Muriel Geldof (Cultural Heritage Agency of The Netherlands) for selecting and sharing the information on the cross-section taken from Bank of the Seine. All the staff of the Van Gogh Museum, the Kroller-Muller Museum, and the Musee d'Orsay are acknowledged for the agreeable cooperation. ; |
Approved |
Most recent IF: 6.32; 2014 IF: 5.636 |
| |
Call Number |
UA @ admin @ c:irua:122100 |
Serial |
5570 |
| Permanent link to this record |
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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 |
| |
Year |
2015 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| |
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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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 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.32 |
Times cited |
36 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 6.32; 2015 IF: 5.636 |
| |
Call Number |
UA @ admin @ c:irua:126583 |
Serial |
5730 |
| Permanent link to this record |
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Author |
Li, L.; Kong, X.; Leenaerts, O.; Chen, X.; Sanyal, B.; Peeters, F.M. |
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Title |
Carbon-rich carbon nitride monolayers with Dirac cones : Dumbbell C4N |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
118 |
Issue |
118 |
Pages |
285-290 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Two-dimensional (2D) carbon nitride materials play an important role in energy-harvesting, energy-storage and environmental applications. Recently, a new carbon nitride, 2D polyaniline (C3N) was proposed [PNAS 113 (2016) 7414-7419]. Based on the structure model of this C3N monolayer, we propose two new carbon nitride monolayers, named dumbbell (DB) C4N-I and C4N-II. Using first-principles calculations, we systematically study the structure, stability, and band structure of these two materials. In contrast to other carbon nitride monolayers, the orbital hybridization of the C/N atoms in the DB C4N monolayers is sp(3). Remarkably, the band structures of the two DB C4N monolayers have a Dirac cone at the K point and their Fermi velocities (2.6/2.4 x 10(5) m/s) are comparable to that of graphene. This makes them promising materials for applications in high-speed electronic devices. Using a tight-binding model, we explain the origin of the Dirac cone. (C) 2017 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000401120800033 |
Publication Date |
2017-03-16 |
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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 |
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 |
36 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 6.337 |
| |
Call Number |
UA @ lucian @ c:irua:143726 |
Serial |
4588 |
| Permanent link to this record |
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Author |
Aussems, D.U.B.; Bal, K.M.; Morgan, T.W.; van de Sanden, M.C.M.; Neyts, E.C. |
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Title |
Mechanisms of elementary hydrogen ion-surface interactions during multilayer graphene etching at high surface temperature as a function of flux |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
137 |
Issue |
|
Pages |
527-532 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In order to optimize the plasma-synthesis and modification process of carbon nanomaterials for applications such as nanoelectronics and energy storage, a deeper understanding of fundamental hydrogengraphite/graphene interactions is required. Atomistic simulations by Molecular Dynamics have proven to be indispensable to illuminate these phenomena. However, severe time-scale limitations restrict them to very fast processes such as reflection, while slow thermal processes such as surface diffusion and molecular desorption are commonly inaccessible. In this work, we could however reach these thermal processes for the first time at time-scales and surface temperatures (1000 K) similar to high-flux plasma exposure experiments during the simulation of multilayer graphene etching by 5 eV H ions. This was achieved by applying the Collective Variable-Driven Hyperdynamics biasing technique, which extended the inter-impact time over a range of six orders of magnitude, down to a more realistic ion-flux of 1023m2s1. The results show that this not only causes a strong shift from predominant ion-to thermally induced interactions, but also significantly affects the hydrogen uptake and surface evolution. This study thus elucidates H ion-graphite/graphene interaction mechanisms and stresses the importance of including long time-scales in atomistic simulations at high surface temperatures to understand the dynamics of the ion-surface system. |
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Wos |
000440661700056 |
Publication Date |
2018-05-24 |
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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 |
4 |
Open Access |
Not_Open_Access: Available from 25.05.2020
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Notes |
DIFFER is part of the Netherlands Organisation for Scientific Research (NWO). K.M.B. is funded as PhD fellow (aspirant) of the FWO-Flanders (Fund for Scientific Research-Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government e department EWI. |
Approved |
Most recent IF: 6.337 |
| |
Call Number |
PLASMANT @ plasmant @c:irua:152172 |
Serial |
4993 |
| Permanent link to this record |
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Author |
De Backer, J.; Razzokov, J.; Hammerschmid, D.; Mensch, C.; Hafideddine, Z.; Kumar, N.; van Raemdonck, G.; Yusupov, M.; Van Doorslaer, S.; Johannessen, C.; Sobott, F.; Bogaerts, A.; Dewilde, S. |
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Title |
The effect of reactive oxygen and nitrogen species on the structure of cytoglobin: A potential tumor suppressor |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Redox Biology |
Abbreviated Journal |
Redox Biol |
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Volume |
19 |
Issue |
|
Pages |
1-10 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Molecular Spectroscopy (MolSpec) |
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Abstract |
Many current anti-cancer therapies rely on increasing the intracellular reactive oxygen and nitrogen species (RONS) contents with the aim to induce irreparable damage, which subsequently results in tumor cell death. A novel tool in cancer therapy is the use of cold atmospheric plasma (CAP), which has been found to be very effective in the treatment of many different cancer cell types in vitro as well as in vivo, mainly through the vast generation of RONS. One of the key determinants of the cell's fate will be the interaction of RONS, generated by CAP, with important proteins, i.e. redox-regulatory proteins. One such protein is cytoglobin (CYGB), a recently discovered globin proposed to be involved in the protection of the cell against oxidative stress. In this study, the effect of plasma-produced RONS on CYGB was investigated through the treatment of CYGB with CAP for different treatment times. Spectroscopic analysis of CYGB showed that although chemical modifications occur, its secondary structure remains intact. Mass spectrometry experiments identified these modifications as oxidations of mainly sulfur-containing and aromatic amino acids. With longer treatment time, the treatment was also found to induce nitration of the heme. Furthermore, the two surface-exposed cysteine residues of CYGB were oxidized upon treatment, leading to the formation of intermolecular disulfide bridges, and potentially also intramolecular disulfide bridges. In addition, molecular dynamics and docking simulations confirmed, and further show, that the formation of an intramolecular disulfide bond, due to oxidative conditions, affects the CYGB 3D structure, thereby opening the access to the heme group, through gate functioning of His117. Altogether, the results obtained in this study (1) show that plasma-produced RONS can extensively oxidize proteins and (2) that the oxidation status of two redox-active cysteines lead to different conformations of CYGB. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
000449722100002 |
Publication Date |
2018-07-24 |
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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 |
2213-2317 |
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 |
|
Open Access |
OpenAccess |
| |
Notes |
M.Y. and N.K. gratefully acknowledge financial support from the Research Foundation – Flanders (FWO), Grant nos. 1200216N and 12J5617N. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI). C.M acknowledges the financial support provided by the Flemish Community and the University of Antwerp (BOF-NOI) for the pre-doctoral scholarship is under grant number/project ID: 28465. S.V.D., S. D. and Z.H. acknowledge the FWO (Grant G.0687.13) and the GOA-BOF UA 2013–2016 (project-ID 28312) for funding. The computational resources and services used in this work were provided by the HPC core facility CalcUA of the Universiteit Antwerpen, and VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI. |
Approved |
Most recent IF: 6.337 |
| |
Call Number |
PLASMANT @ plasmant @c:irua:152818 |
Serial |
5006 |
| Permanent link to this record |
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Author |
Li, L.; Kong, X.; Peeters, F.M. |
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Title |
New nanoporous graphyne monolayer as nodal line semimetal : double Dirac points with an ultrahigh Fermi velocity |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
141 |
Issue |
141 |
Pages |
712-718 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Two-dimensional (2D) carbon materials play an important role in nanomaterials. We propose a new carbon monolayer, named hexagonal-4,4,4-graphyne (H-4,H-4,H-4-graphyne), which is a nanoporous structure composed of rectangular carbon rings and triple bonds of carbon. Using first-principles calculations, we systematically studied the structure, stability, and band structure of this new material. We found that its total energy is lower than that of experimentally synthesized beta-graphdiyne and it is stable at least up to 1500 K. In contrast to the single Dirac point band structure of other 2D carbon monolayers, the band structure of H-4,H-4,H-4-graphyne exhibits double Dirac points along the high-symmetry points and the corresponding Fermi velocities (1.04-1.27 x 10(6) m/s) are asymmetric and higher than that of graphene. The origin of these double Dirac points is traced back to the nodal line states, which can be well explained by a tight-binding model. The H-4,H-4,H-4-graphyne forms a moire superstructure when placed on top of a hexagonal boron nitride substrate. These properties make H-4,H-4,H-4-graphyne a promising semimetal material for applications in high-speed electronic devices. (C) 2018 Elsevier Ltd. All rights reserved. |
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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 |
000450312600072 |
Publication Date |
2018-10-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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 |
43 |
Open Access |
|
| |
Notes |
; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), and the FLAG-ERA project TRANS2DTMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government -department EWI. ; |
Approved |
Most recent IF: 6.337 |
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Call Number |
UA @ admin @ c:irua:155364 |
Serial |
5222 |
| Permanent link to this record |
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Author |
Fukuhara, S.; Bal, K.M.; Neyts, E.C.; Shibuta, Y. |
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Title |
Entropic and enthalpic factors determining the thermodynamics and kinetics of carbon segregation from transition metal nanoparticles |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
171 |
Issue |
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Pages |
806-813 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The free energy surface (FES) for carbon segregation from nickel nanoparticles is obtained from advanced molecular dynamics simulations. A suitable reaction coordinate is developed that can distinguish dissolved carbon atoms from segregated dimers, chains and junctions on the nanoparticle surface. Because of the typically long segregation time scale (up to ms), metadynamics simulations along the developed reaction coordinate are used to construct FES over a wide range of temperatures and carbon concentrations. The FES revealed the relative stability of different stages in the segregation process, and free energy barriers and rates of the individual steps could then be calculated and decomposed into enthalpic and entropic contributions. As the carbon concentration in the nickel nanoparticle increases, segregated carbon becomes more stable in terms of both enthalpy and entropy. The activation free energy of the reaction also decreases with the increase of carbon concentration, which can be mainly attributed to entropic effects. These insights and the methodology developed to obtain them improve our understanding of carbon segregation process across materials science in general, and the nucleation and growth of carbon nanotube in particular. |
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Wos |
000598371500084 |
Publication Date |
2020-09-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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 |
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Open Access |
OpenAccess |
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Notes |
Scientific Research, 19H02415 ; JSPS, 18J22727 ; Japan Society for the Promotion of Science; JSPS; JSPS; FWO; Research Foundation; Flanders, 12ZI420N ; This work was supported by Grant-in-Aid for Scientific Research (B) (No.19H02415) and Grant-in-Aid for JSPS Research Fellow (No.18J22727) from Japan Society for the Promotion of Science (JSPS), Japan. S.F. was supported by JSPS through the Program for 812 |
Approved |
Most recent IF: 6.337 |
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Call Number |
PLASMANT @ plasmant @c:irua:172452 |
Serial |
6421 |
| Permanent link to this record |
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Author |
Pandey, T.; Covaci, L.; Peeters, F.M. |
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Title |
Tuning flexoelectricty and electronic properties of zig-zag graphene nanoribbons by functionalization |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
171 |
Issue |
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Pages |
551-559 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
The flexoelectric and electronic properties of zig-zag graphene nanoribbons are explored under mechanical bending using state of the art first principles calculations. A linear dependence of the bending induced out of plane polarization on the applied strain gradient is found. The inferior flexoelectric properties of graphene nanoribbons can be improved by more than two orders of magnitude by hydrogen and fluorine functionalization (CH and CF nanoribbons). A large out of plane flexoelectric effect is predicted for CF nanoribbons. The origin of this enhancement lies in the electro-negativity difference between carbon and fluorine atoms, which breaks the out of plane charge symmetry even for a small strain gradient. The flexoelectric effect can be further improved by co-functionalization with hydrogen and fluorine (CHF Janus-type nanoribbon), where a spontaneous out of plane dipole moment is formed even for flat nanoribbons. We also find that bending can control the charge localization of valence band maxima and therefore enables the tuning of the hole effective masses and band gaps. These results present an important advance towards the understanding of flexoelectric and electronic properties of hydrogen and fluorine functionalized graphene nanoribbons, which can have important implications for flexible electronic applications. (C) 2020 Elsevier Ltd. All rights reserved. |
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Place of Publication |
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Wos |
000598371500058 |
Publication Date |
2020-09-17 |
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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 |
15 |
Open Access |
OpenAccess |
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Notes |
; The computational resources and services used for the first-principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Flemish Science Foundation (FWO-VI). T. P. is supported by a postdoctoral research fellowship from BOF-UAntwerpen. ; |
Approved |
Most recent IF: 6.337 |
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Call Number |
UA @ admin @ c:irua:175014 |
Serial |
6700 |
| Permanent link to this record |
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Author |
Yusupov, M.; Privat-Maldonado, A.; Cordeiro, R.M.; Verswyvel, H.; Shaw, P.; Razzokov, J.; Smits, E.; Bogaerts, A. |
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Title |
Oxidative damage to hyaluronan–CD44 interactions as an underlying mechanism of action of oxidative stress-inducing cancer therapy |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Redox Biology |
Abbreviated Journal |
Redox Biol |
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Volume |
43 |
Issue |
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Pages |
101968 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Center for Oncological Research (CORE) |
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Abstract |
Multiple cancer therapies nowadays rely on oxidative stress to damage cancer cells. Here we investigated the biological and molecular effect of oxidative stress on the interaction between CD44 and hyaluronan (HA), as interrupting their binding can hinder cancer progression. Our experiments demonstrated that the oxidation of HA decreased its recognition by CD44, which was further enhanced when both CD44 and HA were oxidized. The reduction of CD44–HA binding negatively affected the proliferative state of cancer cells. Our multi-level atomistic simulations revealed that the binding free energy of HA to CD44 decreased upon oxidation. The effect of HA and CD44 oxidation on CD44–HA binding was similar, but when both HA and CD44 were oxidized, the effect was much larger, in agreement with our experiments. Hence, our experiments and computations support our hypothesis on the role of oxidation in the disturbance of CD44–HA interaction, which can lead to the inhibition of proliferative signaling pathways inside the tumor cell to induce cell death. |
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Wos |
000657371800005 |
Publication Date |
2021-04-14 |
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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 |
2213-2317 |
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 |
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Open Access |
OpenAccess |
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Notes |
Fwo; The authors acknowledge the Turing HPC infrastructure at the CalcUA core facility of the University of Antwerp (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA, where all computational work was performed. |
Approved |
Most recent IF: 6.337 |
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Call Number |
PLASMANT @ plasmant @c:irua:177780 |
Serial |
6750 |
| Permanent link to this record |
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Author |
Dehdast, M.; Valiollahi, Z.; Neek-Amal, M.; Van Duppen, B.; Peeters, F.M.; Pourfath, M. |
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Title |
Tunable natural terahertz and mid-infrared hyperbolic plasmons in carbon phosphide |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
178 |
Issue |
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Pages |
625-631 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Hyperbolic polaritons in ultra thin materials such as few layers of van derWaals heterostructures provide a unique control over light-matter interaction at the nanoscale and with various applications in flat optics. Natural hyperbolic surface plasmons have been observed on thin films of WTe2 in the light wavelength range of 16-23 mu m (similar or equal to 13-18 THz) [Nat. Commun. 11, 1158 (2020)]. Using time-dependent density functional theory, it is found that carbon doped monolayer phosphorene (beta-allotrope of carbon phosphide monolayer) exhibits natural hyperbolic plasmons at frequencies above similar or equal to 5 THz which is not observed in its parent materials, i.e. monolayer of black phosphorous and graphene. Furthermore, we found that by electrostatic doping the plasmonic frequency range can be extended to the mid-infrared. (C) 2021 Elsevier Ltd. All rights reserved. |
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Wos |
000648729800057 |
Publication Date |
2021-03-26 |
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Abbreviated Series Title |
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Edition |
|
| |
ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
11 |
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 6.337 |
| |
Call Number |
UA @ admin @ c:irua:179033 |
Serial |
7039 |
| Permanent link to this record |
| |
|
| |
|
Author |
Pierard, N.; Fonseca, A.; Colomer, J.-F.; Bossuot, C.; Benoit, J.-M.; Van Tendeloo, G.; Pirard, J.-P.; Nagy, J.B. |
| |
Title |
Ball milling effect on the structure of single-wall carbon nanotubes |
Type |
A1 Journal article |
| |
Year |
2004 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
42 |
Issue |
8/9 |
Pages |
1691-1697 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
|
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000221948000035 |
Publication Date |
2004-04-09 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
133 |
Open Access |
|
| |
Notes |
Pai/Iuap P5/01 |
Approved |
Most recent IF: 6.337; 2004 IF: 3.331 |
| |
Call Number |
UA @ lucian @ c:irua:54866 |
Serial |
213 |
| Permanent link to this record |
| |
|
| |
|
Author |
Li, Y.; Zhang, X.B.; Tao, X.Y.; Xu, J.M.; Chen, F.; Shen, L.H.; Yang, X.F.; Liu, F.; Van Tendeloo, G.; Geise, H.J. |
| |
Title |
Single phase MgMoO4 as catalyst for the synthesis of bundled multi-wall carbon nanotubes by CVD |
Type |
L1 Letter to the editor |
| |
Year |
2005 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
43 |
Issue |
6 |
Pages |
1325-1328 |
| |
Keywords |
L1 Letter to the editor; Electron microscopy for materials research (EMAT) |
| |
Abstract |
|
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000228676400026 |
Publication Date |
2005-03-11 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
23 |
Open Access |
|
| |
Notes |
Iap V-1 |
Approved |
Most recent IF: 6.337; 2005 IF: 3.419 |
| |
Call Number |
UA @ lucian @ c:irua:59055 |
Serial |
3026 |
| Permanent link to this record |
| |
|
| |
|
Author |
Felten, A.; Ghijsen, J.; Pireaux, J.-J.; Whelan, C.M.; Liang, D.; Van Tendeloo, G.; Bittencourt, C. |
| |
Title |
Photoemission study of CF4 rf-plasma treated multi-wall carbon nanotubes |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
46 |
Issue |
10 |
Pages |
1271-1275 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Multi-wall carbon nanotubes (MWCNTs) were exposed to a CF4 rf-plasma. X-ray photoelectron spectroscopy analysis shows that the treatment effectively grafts fluorine atoms onto the MWCNTs. The fluorine atomic concentration and the nature of the CF bond (semi-ionic or covalent) can be tuned by varying the exposure time. Ultraviolet photoelectron spectroscopy analysis confirms that the valence electronic states are altered by the grafting of fluorine atoms. Characterization with high-resolution transmission electron microscopy reveals that while the plasma treatment does not induce significant etching impact on the CNT-surface, it does increase the number of active sites for gold cluster formation. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000258987500001 |
Publication Date |
2008-05-16 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
21 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 6.337; 2008 IF: 4.373 |
| |
Call Number |
UA @ lucian @ c:irua:76481 |
Serial |
2612 |
| Permanent link to this record |
| |
|
| |
|
Author |
Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A. |
| |
Title |
Density-functional theory calculations of the electron energy-loss near-edge structure of Li-intercalated graphite |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
47 |
Issue |
10 |
Pages |
2501-2510 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
We have studied the structural and electronic properties of lithium-intercalated graphite (LIG) for various Li content. Atomic relaxation shows that Li above the center of the carbon hexagon in a AAAA stacked graphite is the only stable Li configuration in stage 1 intercalated graphite. Lithium and Carbon 1s energy-loss near-edge structure (ELNES) calculations are performed on the Li-intercalated graphite using the core-excited density-functional theory formulation. Several features of the Li 1s ELNES are correlated with reported experimental features. The ELNES spectra of Li is found to be electron beam orientation sensitive and this property is used to assign the origin of the various Li 1s ELNES features. Information about core-hole screening by the valence electrons and charge transfer in the LIG systems is obtained from the C 1s ELNES and valence charge density difference calculations, respectively. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000268429000025 |
Publication Date |
2009-05-11 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
12 |
Open Access |
|
| |
Notes |
Fwo G.0425.05; Esteem 026019 |
Approved |
Most recent IF: 6.337; 2009 IF: 4.504 |
| |
Call Number |
UA @ lucian @ c:irua:77973 |
Serial |
638 |
| Permanent link to this record |
| |
|
| |
|
Author |
Afanasov, I.M.; Shornikova, O.N.; Avdeev, V.V.; Lebedev, O.I.; Van Tendeloo, G.; Matveev, A.T. |
| |
Title |
Expanded graphite as a support for Ni/carbon composites |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
47 |
Issue |
2 |
Pages |
513-518 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Expanded graphite decorated with nickel oxide particles (EGNiO) has been synthesized through electrochemical oxidation of natural graphite in an aqueous nickel nitrate solution followed by a heat treatment. EGNiO was used to prepare nickel/carbon composites using two techniques: (a) hydrogen reduction of nickel oxide particles loaded on the expanded graphite surface and (b) pyrolysis of coal tar pitch-impregnated EGNiO blocks. The EGNiO as well as the nickel/carbon composites have been characterized by X-ray diffraction, scanning and transmission electron microscopy, energy dispersive X-ray spectroscopy and selected area electron diffraction. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000262558300018 |
Publication Date |
2008-11-11 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
45 |
Open Access |
|
| |
Notes |
Iap-Vi |
Approved |
Most recent IF: 6.337; 2009 IF: 4.504 |
| |
Call Number |
UA @ lucian @ c:irua:76033 |
Serial |
1132 |
| Permanent link to this record |
| |
|
| |
|
Author |
Afanasov, I.M.; Morozov, V.A.; Kepman, A.V.; Ionov, S.G.; Seleznev, A.N.; Van Tendeloo, G.; Audeev, V.V. |
| |
Title |
Preparation, electrical and thermal properties of new exfoliated graphite-based composites |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
47 |
Issue |
1 |
Pages |
263-270 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Exfoliated graphite samples (EG) with different bulk densities were prepared by the exfoliation of expandable graphite under a thermal shock regime. As a conductive filler, EG has been incorporated successfully into the coal tar pitch matrix by mechanical mixing. The conducting behavior of the composite was interpreted based on the percolation theory. The percolation threshold of the EG/pitch conducting composites at room temperature was as low as 1.5 wt% and did not depend on the bulk density of the EG used. By means of thermogravimetry the improvement of thermal stability of the composites in comparison with pure pitches was detected. The phenomenon was ascribed to heat shielding effect of the EG particles evidenced by matrix-assisted laser desorption/ionization mass spectrometry. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000262143500032 |
Publication Date |
2008-10-14 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
42 |
Open Access |
|
| |
Notes |
Iap-Vi |
Approved |
Most recent IF: 6.337; 2009 IF: 4.504 |
| |
Call Number |
UA @ lucian @ c:irua:75767 |
Serial |
2701 |
| Permanent link to this record |
| |
|
| |
|
Author |
Afanasov, I.M.; Shornikova, O.N.; Kirilenko, D.A.; Vlasov, I.I.; Zhang, L.; Verbeeck, J.; Avdeev, V.V.; Van Tendeloo, G. |
| |
Title |
Graphite structural transformations during intercalation by HNO3 and exfoliation |
Type |
L1 Letter to the editor |
| |
Year |
2010 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
48 |
Issue |
6 |
Pages |
1862-1865 |
| |
Keywords |
L1 Letter to the editor; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Expandable graphite of two types was synthesized by (1) hydrolysis of graphite nitrate of II stage and (2) anodic polarization of graphite in 60% HNO3. Exfoliated graphite samples were produced by thermal shock of expandable graphite samples in air at 900 °C. A comparative study of microstructural distinctions of both expandable and exfoliated graphite samples was carried out using X-ray diffraction, Raman spectroscopy, electron energy loss spectroscopy and high resolution transmission electron microscopy. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000276132800021 |
Publication Date |
2010-02-02 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
43 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 6.337; 2010 IF: 4.896 |
| |
Call Number |
UA @ lucian @ c:irua:82315UA @ admin @ c:irua:82315 |
Serial |
1379 |
| Permanent link to this record |
| |
|
| |
|
Author |
Launois, P.; Chorro, M.; Verberck, B.; Albouy, P.-A.; Rouzière, S.; Colson, D.; Forget, A.; Noé, L.; Kataura, H.; Monthioux, M.; Cambedouzou, J. |
| |
Title |
Transformation of C70 peapods into double walled carbon nanotubes |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
48 |
Issue |
1 |
Pages |
89-98 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
X-ray diffraction studies comparing the transformation of C(60) and C(70) peapods into double walled carbon nanotubes are presented. The structures of the as-formed DWCNTs are strikingly similar, showing that they are not dependent on the nature of the fullerene precursor. High temperature X-ray diffraction measurements of C(70) peapods below the coalescence temperature show that confined C(70) molecules in large tubes undergo an orientational. transition to free rotations. Fast re-orientations of C(70) molecules allow cyclo-addition between adjacent fullerenes to form, in good agreement with the mechanism of coalescence proposed in the literature for C(60) molecules. (C) 2009 Elsevier Ltd. All rights reserved. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000272018800012 |
Publication Date |
2009-08-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
27 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 6.337; 2010 IF: 4.896 |
| |
Call Number |
UA @ lucian @ c:irua:94389 |
Serial |
3696 |
| Permanent link to this record |
| |
|
| |
|
Author |
Dzhurakhalov, A.A.; Peeters, F.M. |
| |
Title |
Structure and energetics of hydrogen chemisorbed on a single graphene layer to produce graphane |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
49 |
Issue |
10 |
Pages |
3258-3266 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Integrated Molecular Plant Physiology Research (IMPRES) |
| |
Abstract |
Chemisorption of hydrogen on graphene is studied using atomistic simulations with the second generation of reactive empirical bond order Brenner inter-atomic potential. The lowest energy adsorption sites and the most important metastable sites are determined. The H concentration is varied from a single H atom, to clusters of H atoms up to full coverage. We found that when two or more H atoms are present, the most stable configurations of H chemisorption on a single graphene layer are ortho hydrogen pairs adsorbed on one side or on both sides of the graphene sheet. The latter has the highest hydrogen binding energy. The next stable configuration is the orthopara pair combination, and then para hydrogen pairs. The structural changes of graphene caused by chemisorbed hydrogen are discussed and are compared with existing experimental data and other theoretical calculations. The obtained results will be useful for nanoengineering of graphene by hydrogenation and for hydrogen storage. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000291959300014 |
Publication Date |
2011-04-15 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
46 |
Open Access |
|
| |
Notes |
; A.D. thanks M.W. Zhao for a useful correspondence. This work was supported by the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 6.337; 2011 IF: 5.378 |
| |
Call Number |
UA @ lucian @ c:irua:90877 |
Serial |
3275 |
| Permanent link to this record |
| |
|
| |
|
Author |
Shariat, M.; Hosseini, S.I.; Shokri, B.; Neyts, E.C. |
| |
Title |
Plasma enhanced growth of single walled carbon nanotubes at low temperature : a reactive molecular dynamics simulation |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
65 |
Issue |
|
Pages |
269-276 |
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
Low-temperature growth of carbon nanotubes (CNTs) has been claimed to provide a route towards chiral-selective growth, enabling a host of applications. In this contribution, we employ reactive molecular dynamics simulations to demonstrate how plasma-based deposition allows such low-temperature growth. We first show how ion bombardment during the growth affects the carbon dissolution and precipitation process. We then continue to demonstrate how a narrow ion energy window allows CNT growth at 500 K. Finally, we also show how CNTs in contrast cannot be grown in thermal CVD at this low temperature, but only at high temperature, in agreement with experimental data. (C) 2013 Elsevier Ltd. All rights reserved. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000326773200031 |
Publication Date |
2013-08-23 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
21 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 6.337; 2013 IF: 6.160 |
| |
Call Number |
UA @ lucian @ c:irua:112697 |
Serial |
2635 |
| Permanent link to this record |
| |
|
| |
|
Author |
da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
| |
Title |
Analytical study of the energy levels in bilayer graphene quantum dots |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
78 |
Issue |
|
Pages |
392-400 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Using the four-band continuum model we derive a general expression for the infinite-mass boundary condition in bilayer graphene. Applying this new boundary condition we analytically calculate the confined states and the corresponding wave functions in a bilayer graphene quantum dot in the absence and presence of a perpendicular magnetic field. Our results for the energy spectrum show an energy gap between the electron and hole states at small magnetic fields. Furthermore the electron (e) and hole (h) energy levels corresponding to the K and K' valleys exhibit the E-K(e(h)) (m) = E-K'(e(h)) (m) symmetry, where m is the angular momentum quantum number. (C) 2014 Elsevier Ltd. All rights reserved. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000341463900042 |
Publication Date |
2014-07-16 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
35 |
Open Access |
|
| |
Notes |
; This work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the process number BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program Euro-GRAPHENE (project CONGRAN), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). We thank M. Ramezani Masir and M. Grujic for helpful comments and discussions. ; |
Approved |
Most recent IF: 6.337; 2014 IF: 6.196 |
| |
Call Number |
UA @ lucian @ c:irua:119280 |
Serial |
109 |
| Permanent link to this record |
| |
|
| |
|
Author |
Xu, P.; Qi, D.; Schoelz, J.K.; Thompson, J.; Thibado, P.M.; Wheeler, V.D.; Nyakiti, L.O.; Myers-Ward, R.L.; Eddy, C.R.; Gaskill, D.K.; Neek-Amal, M.; Peeters, F.M.; |
| |
Title |
Multilayer graphene, Moire patterns, grain boundaries and defects identified by scanning tunneling microscopy on the m-plane, non-polar surface of SiC |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| |
Volume |
80 |
Issue |
|
Pages |
75-81 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Epitaxial graphene is grown on a non-polar n(+) 6H-SiC m-plane substrate and studied using atomic scale scanning tunneling microscopy. Multilayer graphene is found throughout the surface and exhibits rotational disorder. Moire patterns of different spatial periodicities are found, and we found that as the wavelength increases, so does the amplitude of the modulations. This relationship reveals information about the interplay between the energy required to bend graphene and the interaction energy, i.e. van der Waals energy, with the graphene layer below. Our experiments are supported by theoretical calculations which predict that the membrane topographical amplitude scales with the Moire pattern wavelength, L as L-1 + alpha L-2. (C) 2014 Elsevier Ltd. All rights reserved. |
| |
Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000344132400009 |
Publication Date |
2014-08-19 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
6.337 |
Times cited |
14 |
Open Access |
|
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Notes |
; P.X. and P.M.T. gratefully acknowledge the financial support of ONR under grant N00014-10-1-0181 and NSF under grant DMR-0855358. L.O.N. acknowledges the support of American Society for Engineering Education and Naval Research Laboratory Postdoctoral Fellow Program. Work at the U.S. Naval Research Laboratory is supported by the Office of Naval Research. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem Foundation of the Flemish Government, and the EUROgraphene project CONGRAN. M.N.-A was supported by the EU-Marie Curie IIF postdoc Fellowship 299855. ; |
Approved |
Most recent IF: 6.337; 2014 IF: 6.196 |
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Call Number |
UA @ lucian @ c:irua:121194 |
Serial |
2221 |
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Author |
Nakhaee, M.; Ketabi, S.A.; Peeters, F.M. |
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Title |
Tight-binding studio : a technical software package to find the parameters of tight-binding Hamiltonian |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Computer Physics Communications |
Abbreviated Journal |
Comput Phys Commun |
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Volume |
254 |
Issue |
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Pages |
107379-10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We present the Tight-Binding Studio (TB Studio) software package that calculates the different parameters of a tight-binding Hamiltonian from a set of Bloch energy bands obtained from first principle theories such as density functional theory, Hartree-Fock calculations or semi-empirical band-structure theory. This will be helpful for scientists who are interested in studying electronic and optical properties of structures using Green's function theory within the tight-binding approximation. TB Studio is a cross-platform application written in C++ with a graphical user interface design that is user-friendly and easy to work with. This software is powered by Linear Algebra Package C interface library for solving the eigenvalue problems and the standard high performance OpenGL graphic library for real time plotting. TB Studio and its examples together with the tutorials are available for download from tight-binding.com. Program summary Program Title: Tight-Binding Studio Program Files doi:http://dx.doi.org/10.17632/j6x5mwzm2d.1 Licensing provisions: LGPL Programming language: C++ External routines: BLAS, LAPACK, LAPACKE, wxWidgets, OpenGL, MathGL Nature of problem: Obtaining Tight-Binding Hamiltonian from a set of Bloch energy bands obtained from first-principles calculations. Solution method: Starting from the simplified LCAO method, a tight-binding model in the two-center approximation is constructed. The Slater and Koster (SK) approach is used to calculate the parameters of the TB Hamiltonian. By using non-linear fitting approaches the optimal values of the SK parameters are obtained such that the TB energy eigenvalues are as close as possible to those from first-principles calculations. We obtain the expression for the Hamiltonian and the overlap matrix elements between the different orbitals of the different atoms in an orthogonal or non-orthogonal basis set. (C) 2020 Elsevier B.V. All rights reserved. |
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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 |
000541251200030 |
Publication Date |
2020-05-18 |
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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 |
0010-4655 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.3 |
Times cited |
27 |
Open Access |
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Notes |
; This work was supported by the Methusalem program of the Flemish government, Belgium and M. Nakhaee was supported by a BOF-fellowship (UAntwerpen), Belgium. ; |
Approved |
Most recent IF: 6.3; 2020 IF: 3.936 |
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Call Number |
UA @ admin @ c:irua:170149 |
Serial |
6630 |
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