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Author |
Rouchon, V.; Pellizzi, E.; Duranton, M.; Vanmeert, F.; Janssens, K. |
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Title |
Combining XANES, ICP-AES, and SEM/EDS for the study of phytate chelating treatments used on iron gall ink damaged manuscripts |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
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Volume |
26 |
Issue |
12 |
Pages |
2434-2441 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Many historical documents written with iron gall inks are endangered by the corrosive effects of these inks. In this work, a combination of complementary analytical methods was used for the first time in order to study the phytate process which is used in conservation studios to stabilize damaged manuscripts. This process consists of an antioxidant treatment performed by means of a calcium phytate (CP) solution, followed by a deacidification treatment performed with a calcium carbonate (CC) solution. The antioxidant treatment capitalizes on the properties of myo-inositol hexaphosphoric acid (phytic acid) that inhibits iron through chelation. In order to use relatively low acidic solutions, the pH of the CP solution is increased up to values between 5 and 6, which is in the range of the CP precipitation threshold. This study was performed on laboratory samples made of paper impregnated with iron gall ink and artificially aged in climatic chambers. It aims to investigate how the CP precipitate impacts the efficiency of the treatment. Side effects, such as elemental losses and deposits, were measured by means of several analytical techniques (FeK Edge XANES, SEM/EDS, and ICP-AES). These measurements were crosschecked with a ready to use colour spot test made of bathophenanthroline impregnated paper. It appeared that the CP treatment should necessarily be followed by the deacidification treatment in order to achieve long term stability. The precipitation of CP in the treating solution does finally not impact the efficiency of the treatment despite the fact that it should theoretically lower the availability of phytate to chelate iron. A scenario is proposed to explain this point. |
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Wos |
000297030400008 |
Publication Date |
2011-10-06 |
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Edition |
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ISSN |
0267-9477 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.379 |
Times cited |
10 |
Open Access |
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Notes |
; This research was funded by SOLEIL (proposals 20060396 and 20080761) 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) projects no. G.0704.08 and G.01769.09. We are thankful to the paper conservator students of the Institut National du Patrimoine who were involved in some of the sample preparations, and to Dr Dominique Thiaudiere and Dr Solenn Reguer for their assistance and help during the experiments performed at SOLEIL beamline “DIFFABS”. ; |
Approved |
Most recent IF: 3.379; 2011 IF: 3.220 |
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Call Number |
UA @ admin @ c:irua:93845 |
Serial |
5527 |
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Permanent link to this record |
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Author |
Cagno, S.; Nuyts, G.; Bugani, S.; De Vis, K.; Schalm, O.; Caen, J.; Helfen, L.; Cotte, M.; Reischig, P.; Janssens, K. |
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Title |
Evaluation of manganese-bodies removal in historical stained glass windows via SR-\mu-XANES/XRF and SR-\mu-CT |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of analytical atomic spectrometry |
Abbreviated Journal |
J Anal Atom Spectrom |
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Volume |
26 |
Issue |
12 |
Pages |
2442-2451 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The speed and effectiveness of a conservation treatment used for stained glass windows have been investigated. Dark-coloured Mn-rich stains can be found in the alteration layer of ancient glass artefacts and cause the surface to turn brown/black: this phenomenon is known as Mn-browning or Mn-staining. While in glass manganese is present in the +II or +III oxidation states, in the Mn-rich bodies, manganese is in a higher oxidation state (+IV). In restoration practice, mildly reducing solutions are employed to eliminate the dark colour and restore the clear appearance of the glass. In this paper the effectiveness and side effects of the use of hydroxylamine hydrochloride for this purpose are assessed. Archaeological fragments of stained glass windows, dated to the 14th century and originating from Sidney Sussex College, Cambridge (UK), were examined by means of synchrotron radiation (SR) based microscopic X-ray Absorption Near-Edge Spectroscopy (μ-XANES) and microscopic X-Ray Fluorescence (μ-XRF) and with high resolution computed absorption tomography (μ-CT) before, during and after the treatment. The monitoring of the glass fragments during the treatment allows us to better understand the manner in which the process unfolds and its kinetics. The results obtained reveal that the hydroxylamine hydrochloride treatment is effective, but also that it has a number of unwanted side effects. These findings are useful for optimizing the time and other modalities of the Mn-reducing treatment as well as minimizing its unwanted results. |
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Wos |
000297030400009 |
Publication Date |
2011-10-11 |
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Edition |
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ISSN |
0267-9477 |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.379 |
Times cited |
17 |
Open Access |
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Notes |
; This research was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) projects no. G.0704.08 and G.01769.09. Special thanks to Ms Leonie Seliger, head of the stained-glass conservation studio (The Cathedral Studios-The Chapter of Canterbury Cathedral) for the supply of the archaeological samples. The authors gratefully acknowledge ESRF for granting beamtime (proposal EC-602). ; |
Approved |
Most recent IF: 3.379; 2011 IF: 3.220 |
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Call Number |
UA @ admin @ c:irua:93848 |
Serial |
5613 |
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Permanent link to this record |
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Author |
Legrand, S.; Alfeld, M.; Vanmeert, F.; de Nolf, W.; Janssens, K. |
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Title |
Macroscopic Fourier transform infrared scanning in reflection mode (MA-rFTIR), a new tool for chemical imaging of cultural heritage artefacts in the mid-infrared range |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
The analyst |
Abbreviated Journal |
Analyst |
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Volume |
139 |
Issue |
10 |
Pages |
2489-2498 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
In this paper we demonstrate that by means of scanning reflection FTIR spectroscopy, it is possible to record highly specific distribution maps of organic and inorganic compounds from flat, macroscopic objects with cultural heritage value in a non-invasive manner. Our previous work involved the recording of macroscopic distributions of chemical elements or crystal phases from painted works of art based on respectively macroscopic X-ray fluorescence or X-ray powder diffraction analysis. The use of infrared radiation instead of X-rays has the advantage that more specific information about the nature and distribution of the chemical compounds present can be gathered. This higher imaging specificity represents a clear advantage for the characterization of painting and artist materials. It allows the distribution of metallo-organic compounds to be visualized and permits distinguishing between pigmented materials containing the same key metal. The prototype instrument allows the recording of hyperspectral datacubes by scanning the surface of the artefact in a contactless and sequential single-point measuring mode, while recording the spectrum of reflected infrared radiation. After the acquisition, spectral line intensities of individual bands and chemical distribution maps can be extracted from the datacube to identify the compounds present and/or to highlight their spatial distribution. Not only is information gained on the surface of the investigated artefacts, but also images of overpainted paint layers and, if present, the underdrawing may be revealed in this manner. A current major limitation is the long scanning times required to record these maps. |
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Wos |
000334734200028 |
Publication Date |
2014-02-19 |
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Edition |
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ISSN |
0003-2654 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.885 |
Times cited |
25 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.885; 2014 IF: 4.107 |
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Call Number |
UA @ admin @ c:irua:116595 |
Serial |
5699 |
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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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Wos |
000288887700028 |
Publication Date |
2011-03-04 |
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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 |
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Permanent link to this record |
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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 |
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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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Wos |
000264759400025 |
Publication Date |
2009-03-11 |
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Abbreviated Series Title |
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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 |
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Author |
Al-Emam, E.; Beltran, V.; De Meyer, S.; Nuyts, G.; Wetemans, V.; De Wael, K.; Caen, J.; Janssens, K. |
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Title |
Removal of a past varnish treatment from a 19th-century Belgian wall painting by means of a solvent-loaded double network hydrogel |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Polymers |
Abbreviated Journal |
Polymers-Basel |
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Volume |
13 |
Issue |
16 |
Pages |
2651-20 |
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Keywords |
A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
Polymeric materials have been used by painting conservator-restorers as consolidants and/or varnishes for wall paintings. The application of these materials is carried out when confronting loose paint layers or as a protective coating. However, these materials deteriorate and cause physiochemical alterations to the treated surface. In the past, the monumental neo-gothic wall painting 'The Last Judgment' in the chapel of Sint-Jan Berchmanscollege in Antwerp, Belgium was treated with a synthetic polymeric material. This varnish deteriorated significantly and turned brown, obscuring the paint layers. Given also that the varnish was applied to some parts of the wall painting and did not cover the entire surface, it was necessary to remove it in order to restore the original appearance of the wall painting. Previous attempts carried out by conservator-restorers made use of traditional cleaning methods, which led to damage of the fragile paint layers. Therefore, gel cleaning was proposed as a less invasive and more controllable method for gently softening and removing the varnish. The work started by identifying the paint stratigraphy and the deteriorated varnish via optical microscopy (OM), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. A polyvinyl alcohol-borax/agarose (PVA-B/AG) hydrogel loaded with a number of solvents/solvent mixtures was employed in a series of tests to select the most suitable hydrogel composite. By means of the hydrogel composite loaded with 10% propylene carbonate, it was possible to safely remove the brown varnish layer. The results were verified by visual examinations (under visible light 'VIS' and ultraviolet light 'UV') as well as OM and FTIR spectroscopy. |
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Wos |
000690248000001 |
Publication Date |
2021-08-10 |
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Abbreviated Series Title |
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Edition |
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ISSN |
2073-4360 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.364 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.364 |
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Call Number |
UA @ admin @ c:irua:181567 |
Serial |
8470 |
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Author |
Ceglia, A.; Nuyts, G.; Cagno, S.; Meulebroeck, W.; Baert, K.; Cosyns, P.; Nys, K.; Thienpont, H.; Janssens, K.; Terryn, H. |
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Title |
A XANES study of chromophores : the case of black glass |
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A1 Journal article |
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Year |
2014 |
Publication |
Analytical methods |
Abbreviated Journal |
Anal Methods-Uk |
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Volume |
6 |
Issue |
8 |
Pages |
2662-2671 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
We studied the Fe K-edge X-ray absorption near edge (XANES) spectra of several Roman black glass fragments in order to determine the Fe3+/ΣFe ratio of these materials. The selected archaeological glass samples cover the period 1st5th century AD in nine different sites of the North Western provinces of the Roman Empire. The fragments belong to two different compositional groups demonstrating a diachronic evolution: early Roman HMG (High Magnesia Glass) and Roman Imperial LMG (Low Magnesia Glass). The first group contains natural Fe levels (below 2 wt% as Fe2O3), while the LMG has concentrations above 5 wt%. This difference is also reflected by Fe3+/ΣFe values. Low iron glass was produced under strongly reducing conditions in order to obtain the black colour, with average Fe3+/ΣFe values ≈ 0.17. LMG glass is somewhat more oxidised (Fe3+/ΣFe ≈ 0.40.5). While HMG glass required active control of the furnace environment, LMG was made under ambient atmosphere and its higher oxidation degree is mainly determined by the chemistry of the raw glass. |
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Wos |
000333524200032 |
Publication Date |
2014-02-05 |
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Series Volume |
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Edition |
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ISSN |
1759-9660 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.9 |
Times cited |
14 |
Open Access |
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Notes |
; The authors are grateful to the staff of beamline L in HASYLAB for their helpful support. The research leading to these results has received funding from the European Union Seventh Framework Programme FP7/2007-2013 under grant agreement no. 265010. Support from the University of Antwerp Research Council through GOA Programme “XANES meets ELNES” is gratefully acknowledged. This work was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/F50. We would like to thank M. P. Riccardi and E. Basso of the University of Pavia and R. Falcone of the Stazione Sperimentale del Vetro who provided us with the reference glasses. ; |
Approved |
Most recent IF: 1.9; 2014 IF: 1.821 |
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Call Number |
UA @ admin @ c:irua:116596 |
Serial |
5919 |
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Author |
Terzano, R.; Santoro, A.; Spagnuolo, M.; Vekemans, B.; Medici, L.; Janssens, K.; Göttlicher, J.; Denecke, M.A.; Mangold, S.; Ruggiero, P. |
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Title |
Solving mercury (Hg) speciation in soil samples by synchrotron X-ray microspectroscopic techniques |
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A1 Journal article |
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Year |
2010 |
Publication |
Environmental pollution |
Abbreviated Journal |
Environ Pollut |
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Volume |
158 |
Issue |
8 |
Pages |
2702-2709 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg1. Hg chemical forms were identified and quantified by sequential extractions and bulkand micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as m-XRF, m-XRD and m-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 mm. The main Hg-species found in the soil samples were metacinnabar (b-HgS), cinnabar (a-HgS), corderoite (Hg3S2Cl2), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 mm. No interaction among Hg-species and soil components was observed. All the observed Hgspecies originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution. |
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Wos |
000280571500026 |
Publication Date |
2010-06-08 |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
0269-7491 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.099 |
Times cited |
30 |
Open Access |
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Notes |
; This research was partially financed by the MIUR (COFIN 2005) project “Innovative chemical, physical, and biological methods to characterize and remediate soils polluted by heavy metals (MICROS)”. Synchrotron experiments at HASYLAB were financially supported by the European Community-Research Infrastructure Action under the FP6 “Structuring the European Research Area” Program I(Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). This research was also performed as part of the “Interuniversity Attraction Poles” (IAP6) Program financed by the Belgian government. We thank Gerald Falkenberg and Karen Rickers-Appel for their scientific and technical support in obtaining the experimental data at Beam line L (HASYLAB, DESY, Hamburg, Germany). ; |
Approved |
Most recent IF: 5.099; 2010 IF: 3.395 |
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Call Number |
UA @ admin @ c:irua:84050 |
Serial |
5835 |
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Permanent link to this record |
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Author |
Simionovici, A.S.; Chukalina, M.; Schroer, C.; Drakopoulos, M.; Snigirev, A.; Snigireva, I.; Lengeler, B.; Janssens, K.; Adams, F. |
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Title |
High-resolution X-ray fluorescence microtomography of homogeneous samples |
Type |
A1 Journal article |
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Year |
2000 |
Publication |
IEEE transactions on nuclear science |
Abbreviated Journal |
Ieee T Nucl Sci |
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Volume |
47 |
Issue |
6 |
Pages |
2736-2740 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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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 |
000166992400006 |
Publication Date |
2002-08-24 |
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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 |
|
|
|
ISSN |
0018-9499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
1.171 |
Times cited |
|
Open Access |
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|
Notes |
|
Approved |
Most recent IF: 1.171; 2000 IF: 1.060 |
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Call Number |
UA @ admin @ c:irua:32403 |
Serial |
5644 |
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Permanent link to this record |
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Author |
Marchetti, A.; Saniz, R.; Krishnan, D.; Rabbachin, L.; Nuyts, G.; De Meyer, S.; Verbeeck, J.; Janssens, K.; Pelosi, C.; Lamoen, D.; Partoens, B.; De Wael, K. |
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Title |
Unraveling the Role of Lattice Substitutions on the Stabilization of the Intrinsically Unstable Pb2Sb2O7Pyrochlore: Explaining the Lightfastness of Lead Pyroantimonate Artists’ Pigments |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
|
|
Volume |
32 |
Issue |
7 |
Pages |
2863-2873 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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|
Abstract |
The pyroantimonate pigments Naples yellow and lead tin antimonate yellow are recognized as some of the most stable synthetic yellow pigments in the history of art. However, this exceptional lightfastness is in contrast with experimental evidence suggesting that this class of mixed oxides is of semiconducting nature. In this study the electronic structure and light-induced behavior of the lead pyroantimonate pigments were determined by means of a combined multifaceted analytical and computational approach (photoelectrochemical measurements, UV-vis diffuse reflectance spectroscopy, STEM-EDS, STEM-HAADF, and density functional theory calculations). The results demonstrate both the semiconducting nature and the lightfastness of these pigments. Poor optical absorption and minority carrier mobility are the main properties responsible for the observed stability. In addition, novel fundamental insights into the role played by Na atoms in the stabilization of the otherwise intrinsically unstable Pb2Sb2O7 pyrochlore were obtained. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000526394000016 |
Publication Date |
2020-04-14 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
8.6 |
Times cited |
8 |
Open Access |
OpenAccess |
|
|
Notes |
Universiteit Antwerpen; Belgian Federal Science Policy Office; |
Approved |
Most recent IF: 8.6; 2020 IF: 9.466 |
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Call Number |
EMAT @ emat @c:irua:168819 |
Serial |
6363 |
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Permanent link to this record |
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Author |
Cagno, S.; Mendera, M.; Jeffries, T.; Janssens, K. |
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Title |
Raw materials for medieval to post-medieval Tuscan glassmaking : new insight from LA-ICP-MS analyses |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Journal of archaeological science |
Abbreviated Journal |
J Archaeol Sci |
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|
Volume |
37 |
Issue |
12 |
Pages |
3030-3036 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
LA-ICP-MS analyses were performed on a set of Tuscan (post) medieval archaeological glass finds dated to the 1316th century in order to quantitatively determine the trace element contents. The results are used for defining and distinguishing several compositional groups. The trace element data are consistent with the distinctions obtained by considering the major element data determined via quantitative SEM-EDX, but allow to obtain new insights into the nature and quality of the silica sources employed and the presumed method of ash purification. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000283903500008 |
Publication Date |
2010-07-06 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0305-4403 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
2.602 |
Times cited |
38 |
Open Access |
|
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|
Notes |
; This research was supported by the Interuniversity Attraction Poles Program – Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “Atom” (Research Fund University of Antwerp, Belgium) and of FWO (Brussels, Belgium) projects no. G.0177.03, G.0103.04 and G.0689.06. ; |
Approved |
Most recent IF: 2.602; 2010 IF: 1.710 |
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Call Number |
UA @ admin @ c:irua:85814 |
Serial |
5802 |
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Permanent link to this record |
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Author |
Cagno, S.; van der Snickt, G.; Legrand, S.; Caen, J.; Patin, M.; Meulebroeck, W.; Dirkx, Y.; Hillen, M.; Steenackers, G.; Rousaki, A.; Vandenabeele, P.; Janssens, K. |
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Title |
Comparison of four mobile, non‐invasive diagnostic techniques for differentiating glass types in historical leaded windows : MA‐XRF , UV–Vis–NIR, Raman spectroscopy and IRT |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
X-Ray Spectrometry |
Abbreviated Journal |
X-Ray Spectrom |
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Volume |
|
Issue |
|
Pages |
xrs.3185-17 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
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Abstract |
This paper critically compares the performance of four non-invasive techniques that match the accuracy, flexibility, time-efficiency, and transportability required for in situ characterization of leaded glass windows: macroscopic X-ray fluorescence imaging (MA-XRF), UV-Vis-NIR, Raman spectroscopy, and infrared thermography (IRT). In order to compare the techniques on equal grounds, all techniques were tested independently of each other by separate research groups on the same historical leaded window tentatively dated to the 17th century, without prior knowledge. The aim was to assess the ability of these techniques to document the conservation history of the window by classifying and grouping the colorless glass panes, based on differences in composition. IRT, MA-XRF and UV-Vis-NIR spectroscopy positively distinguished at least two glass groups, with MA-XRF providing the most detailed chemical information. In particular, based on the ratio between the network modifier (K) and network stabilizer (Ca) and on the level of colorants and decolorizers (Fe, Mn, As), the number of plausible glass families could be strongly reduced. In addition, UV-Vis-NIR detected cobalt at ppm level and gave more specific information on the chromophore Fe2+/Fe(3+)ratio. Raman spectroscopy was hampered by fluorescence caused by the metal ions of the decolorizer in most of the panes, but nevertheless identified one group as HLLA. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000561869600001 |
Publication Date |
2020-08-24 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
|
|
ISSN |
0049-8246 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
1.2 |
Times cited |
|
Open Access |
|
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|
Notes |
; Belgian Federal Science Policy Office, Grant/Award Number: BR/175/A3/FENESTRA; Fonds Wetenschappelijk Onderzoek, Grant/Award Number: 12X1919N; Baillet-Latour Fund ; |
Approved |
Most recent IF: 1.2; 2020 IF: 1.298 |
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Call Number |
UA @ admin @ c:irua:170972 |
Serial |
6473 |
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Permanent link to this record |
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Author |
Terzano, R.; al Chami, Z.; Vekemans, B.; Janssens, K.; Miano, T.; Ruggiero, P. |
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Title |
Zinc distribution and speciation within rocket plants (Eruca vesicaria L. Cavalieri) grown on a polluted soil amended with compost as determined by XRF microtomography and Micro-Xanes |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Journal of agricultural and food chemistry |
Abbreviated Journal |
J Agr Food Chem |
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Volume |
56 |
Issue |
9 |
Pages |
3222-3231 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000255655600050 |
Publication Date |
2008-04-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
|
|
ISSN |
0021-8561 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.154 |
Times cited |
68 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.154; 2008 IF: 2.562 |
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Call Number |
UA @ admin @ c:irua:69147 |
Serial |
5925 |
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Permanent link to this record |
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Author |
Rahemi, V.; Sarmadian, N.; Anaf, W.; Janssens, K.; Lamoen, D.; Partoens, B.; De Wael, K. |
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Title |
Unique opto-electronic structure and photo reduction properties of sulfur doped lead chromates explaining their instability in paintings |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
89 |
Issue |
89 |
Pages |
3326-3334 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artists material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods. Pure PbCrO4 (crocoite in its natural form) has a deep yellow color and is relatively stable, while the co-precipitate with lead sulfate (PbCr1-xSxO4) has a paler shade and seems to degrade faster. This degradation is assumed to be related to the reduction of Cr(VI) to Cr(III). We show that on increasing the sulfur(S)-content in chrome yellow, the band gap increases. Typically, when increasing the band gap, one might assume that a decrease in photo activity is the result. However, the photo activity relative to the Cr content, and thus Cr reduction, of sulfur-rich PbCr1-xSxO4 is found to be much higher compared to the sulfur-poor or non-doped lead chromates. This discrepancy can be explained by the evolution of the crystal and electronic structure as function of the sulfur content: first-principles density functional theory calculations show that both the absorption coefficient and reflection coefficients of the lead chromates change as a result of the sulfate doping in such a way that the generation of electron-hole pairs under illumination relative to the total Cr content increases. These changes in the material properties explain why paler shade yellow colors of this pigment are more prone to discoloration. The electronic structure calculations also demonstrate that lead chromate and its co-precipitates are p-type semiconductors, which explains the observed reduction reaction. As understanding this phenomenon is valuable in the field of cultural heritage, this study is the first joint action of photo-electrochemical measurements and first-principles calculations to approve the higher tendency of sulfur-rich lead chromates to darken. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000397478300015 |
Publication Date |
2017-02-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
0003-2700 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
6.32 |
Times cited |
7 |
Open Access |
OpenAccess |
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|
Notes |
; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government, department EWI. The BOF-GOA action SOLARPAINT of the University of Antwerp Research Council is acknowledged for financial support. W.A. acknowledges support from BELSPO project S2-ART. Dr. L. Monico and Dr. C. Miliani (ISTM, Perugia) are gratefully acknowledged for helpful discussions and for providing some of the initial batches of the materials studied. ; |
Approved |
Most recent IF: 6.32 |
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Call Number |
UA @ lucian @ c:irua:140886 |
Serial |
4451 |
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Permanent link to this record |
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Author |
Terzano, R.; Alfeld, M.; Janssens, K.; Vekemans, B.; Schoonjans, T.; Vincze, L.; Tomasi, N.; Pinton, R.; Cesco, S. |
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Title |
Spatially resolved (semi)quantitative determination of iron (Fe) in plants by means of synchrotron micro X-ray fluorescence |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
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Volume |
405 |
Issue |
10 |
Pages |
3341-3350 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Iron (Fe) is an essential element for plant growth and development; hence determining Fe distribution and concentration inside plant organs at the microscopic level is of great relevance to better understand its metabolism and bioavailability through the food chain. Among the available microanalytical techniques, synchrotron mu-XRF methods can provide a powerful and versatile array of analytical tools to study Fe distribution within plant samples. In the last years, the implementation of new algorithms and detection technologies has opened the way to more accurate (semi)quantitative analyses of complex matrices like plant materials. In this paper, for the first time the distribution of Fe within tomato roots has been imaged and quantified by means of confocal mu-XRF and exploiting a recently developed fundamental parameter-based algorithm. With this approach, Fe concentrations ranging from few hundreds of ppb to several hundreds of ppm can be determined at the microscopic level without cutting sections. Furthermore, Fe (semi)quantitative distribution maps were obtained for the first time by using two opposing detectors to collect simultaneously the XRF radiation emerging from both sides of an intact cucumber leaf. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000316338700033 |
Publication Date |
2013-02-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.431 |
Times cited |
27 |
Open Access |
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|
Notes |
; Research was supported by grants from Italian MIUR (FIRB-Programma “Futuro in Ricerca”) and Free University of Bolzano (TN5046 and TN5056). Synchrotron experiments at HASY-LAB were financially supported by the European Community Research Infrastructure Action under the FP6 “Structuring the European Research Area” Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). Matthias Alfeld receives a Ph.D. fellowship of the Research Foundation-Flanders (FWO). We thank Karen Rickers-Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; |
Approved |
Most recent IF: 3.431; 2013 IF: 3.578 |
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Call Number |
UA @ admin @ c:irua:108261 |
Serial |
5838 |
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Permanent link to this record |
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Author |
van der Snickt, G.; Dooley, K.A.; Sanyova, J.; Dubois, H.; Delaney, J.K.; Gifford, E.M.; Legrand, S.; Laquiere, N.; Janssens, K. |
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Title |
Dual mode standoff imaging spectroscopy documents the painting process of the Lamb of God in the Ghent Altarpiece by J. and H. Van Eyck |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Science Advances |
Abbreviated Journal |
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Volume |
6 |
Issue |
31 |
Pages |
eabb3379 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
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Abstract |
The ongoing conservation treatment program of the Ghent Altarpiece by Hubert and Jan Van Eyck, one of the iconic paintings of the west, has revealed that the designs of the paintings were changed several times, first by the original artists, and then during later restorations. The central motif, The Lamb of God, representing Christ, plays an essential iconographic role, and its depiction is important. Because of the prevalence of lead white, it was not possible to visualize the Van Eycks' original underdrawing of the Lamb, their design changes, and the overpaint by later restorers with a single spectral imaging modality. However, by using elemental (x-ray fluorescence) and molecular (infrared reflectance) imaging spectroscopies, followed by analysis of the resulting data cubes, the necessary chemical contrast could be achieved. In this way, the two complementary modalities provided a more complete picture of the development and changes made to the Lamb. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000556543100033 |
Publication Date |
2020-07-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
2375-2548 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.6 |
Times cited |
|
Open Access |
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|
Notes |
; This research was part of the activities of the Chair on Advanced Imaging Techniques for the Arts, established by the Baillet Latour fund. In addition, it was supported by the Belgian Science Policy Office (Project MO/39/011) and the Gieskes-Strijbis fund. We are also indebted to the BOF-GOA SOLARPaint project of the University of Antwerp Research Council and to FWO (Brussels) projects G056619N and G054719N. J.K.D. and K.A.D. acknowledge support from the National Gallery of Art. ; |
Approved |
Most recent IF: 13.6; 2020 IF: NA |
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Call Number |
UA @ admin @ c:irua:171270 |
Serial |
6494 |
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Permanent link to this record |
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Author |
Vincze, L.; Janssens, K.; Adams, F.; Engström, P.; Rindby, A. |
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Title |
Interpretation of cappilary generated spatial and angular distribution of X-rays: theoretical modeling and experimental verification using the European Synchrotron Radiation Facility Optical Beamline |
Type |
A1 Journal article |
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Year |
1998 |
Publication |
The review of scientific instruments |
Abbreviated Journal |
Rev Sci Instrum |
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Volume |
69 |
Issue |
10 |
Pages |
3494-3503 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000076430000005 |
Publication Date |
2002-07-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0034-6748 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.515 |
Times cited |
|
Open Access |
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Notes |
|
Approved |
Most recent IF: 1.515; 1998 IF: 1.177 |
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Call Number |
UA @ admin @ c:irua:22764 |
Serial |
5669 |
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Permanent link to this record |
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Author |
Monico, L.; Cartechini, L.; Rosi, F.; Chieli, A.; Grazia, C.; De Meyer, S.; Nuyts, G.; Vanmeert, F.; Janssens, K.; Cotte, M.; De Nolf, W.; Falkenberg, G.; Sandu, I.C.A.; Tveit, E.S.; Mass, J.; De Freitas, R.P.; Romani, A.; Miliani, C. |
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Title |
Probing the chemistry of CdS paints in The Scream by in situ noninvasive spectroscopies and synchrotron radiation x-ray techniques |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Science Advances |
Abbreviated Journal |
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Volume |
6 |
Issue |
20 |
Pages |
eaay3514 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The degradation of cadmium sulfide (CdS)-based oil paints is a phenomenon potentially threatening the iconic painting The Scream (ca. 1910) by Edvard Munch (Munch Museum, Oslo) that is still poorly understood. Here, we provide evidence for the presence of cadmium sulfate and sulfites as alteration products of the original CdS-based paint and explore the external circumstances and internal factors causing this transformation. Macroscale in situ noninvasive spectroscopy studies of the painting in combination with synchrotron-radiation x-ray microspectroscopy investigations of a microsample and artificially aged mock-ups show that moisture and mobile chlorine compounds are key factors for promoting the oxidation of CdS, while light (photodegradation) plays a less important role. Furthermore, under exposure to humidity, parallel/secondary reactions involving dissolution, migration through the paint, and recrystallization of water-soluble phases of the paint are associated with the formation of cadmium sulfates. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000533573300009 |
Publication Date |
2020-05-16 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
2375-2548 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
13.6 |
Times cited |
4 |
Open Access |
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|
Notes |
; The research was financially supported by the European research project IPERION-CH, funded by the European Commission, H2020-INFRAIA-2014-2015 (grant agreement no. 654028); the project AMIS, within the program Dipartimenti di Eccellenza 2018-2022 (funded by MIUR and University of Perugia); and the program “Ricerca di Base 2017” (funded by University of Perugia). S.D.M. and K.J. acknowledge the GOA Project SolarPaint from the University of Antwerp Research Council and projects G056619N and G054719N from FWO (Brussels). F.V. and K.J. acknowledge support from Interreg Project Smart*Light and thank BELSPO (Brussels) for financial support via FED-tWIN mandate PRF055. L.M. acknowledges the Erasmus+ program (Staff Mobility for training, A. Y. 2018 to 2019) of the European Commission. In situ noninvasive analyses were performed using the European MOLAB platform, which is financially supported by the European project IPERION-CH. For the beamtime grants received, the authors thank the ESRF-ID21 beamline (experiment nos. HG32, HG64, and HG95), DESY-P06 beamline, a member of the Helmholtz Association HGF (experiment nos. I-20130221 EC and I-20160126 EC), and the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. ; |
Approved |
Most recent IF: 13.6; 2020 IF: NA |
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Call Number |
UA @ admin @ c:irua:169519 |
Serial |
6585 |
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Permanent link to this record |
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Author |
Vanmeert, F.; van der Snickt, G.; Janssens, K. |
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Title |
Plumbonacrite identified by X-ray powder diffraction tomography as a missing link during degradation of red lead in a Van Gogh painting |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
54 |
Issue |
12 |
Pages |
3607-3610 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Red lead, a semiconductor pigment used by artists since antiquity, is known to undergo several discoloration phenomena. These transformations are either described as darkening of the pigment caused by the formation of either plattnerite (β-PbO2) or galena (PbS) or as whitening by which red lead is converted into anglesite (PbSO4) or (hydro)cerussite (2 PbCO3⋅Pb(OH)2; PbCO3). X-ray powder diffraction tomography, a powerful analytical method that allows visualization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting. A very rare lead mineral, plumbonacrite (3 PbCO3⋅ Pb(OH)2⋅PbO), was revealed to be present. This is the first reported occurrence of this compound in a painting dating from before the mid 20th century. It constitutes the missing link between on the one hand the photoinduced reduction of red lead and on the other hand (hydro)cerussite, and thus sheds new light on the whitening of red lead. |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000351178300008 |
Publication Date |
2015-02-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
24 |
Open Access |
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Notes |
; The authors acknowledge L. Van der Loeff and M. Leeuwestein (Kroller-Muller Museum) for providing the paint sample. We thank Dr. J. Jaroszewicz (WUT) for performing the CT measurements. This research was carried out at the light source PETRA III at DESY, a member of the Helmholtz Association (HGF). We thank Dr. G. Falkenberg and the members of his team for their assistance in using beam line P06. We acknowledge financial support from the University of Antwerp GOA projects “XANES meets EELS” and “SOLARPaint”, as well as from BELSPO (Brussels) Project S2-ART and FWO (Brussels) project “ESRF-Dubble”. ; |
Approved |
Most recent IF: 11.994; 2015 IF: 11.261 |
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Call Number |
UA @ admin @ c:irua:124620 |
Serial |
5774 |
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Permanent link to this record |
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Author |
Benito, P.; de Nolf, W.; Nuyts, G.; Janssens, K.; et al. |
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Title |
Role of coating-metallic support interaction in the properties of electrosynthesized Rh-based structured catalysts |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
ACS catalysis |
Abbreviated Journal |
Acs Catal |
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Volume |
4 |
Issue |
10 |
Pages |
3779-3790 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Rh-structured catalysts for the catalytic partial oxidation of CH4 to syngas were prepared by electrosynthesis of Rh-containing hydrotalcite-type (HT) compounds on FeCrAlloy foams followed by calcination at 900 degrees C. During the calcination the simultaneous decomposition of the layered HT structure and formation of the protective FeCrAlloy outer shell in alumina occurred. Here, we studied the role of the coating-metallic support interaction in the properties of the catalysts after calcination, H-2 reduction, and catalytic tests, by a combination of electron (FEG-SEM/EDS) and synchrotron X-ray (XRF/XRPD and XRF/XANES) microscopic techniques. The characterization of crystalline phases in the metallic support and coating and distribution of Rh active species was carried out on several samples prepared by modifying the Rh content in the electrolytic solution (Rh/Mg/Al = 11.0/70.0/19.0, 5.0/70.0/25.0, 0/70.0/30.0 atomic ratio). A sample was also prepared with no aluminum in the electrolytic solution (Rh/Mg/Al = 13.6/86.4/0.0 atomic ratio) and calcined at 550 and 900 degrees C. The interaction between the elements of the metallic support and the catalytic coating increased the film adhesion during the thermal treatment and catalytic tests and modified the catalyst crystalline phases. A chemical reaction between Al corning from the foam and Mg in the coating occurred during calcination at high temperature leading to the formation of spinel phases in which rhodium is solved, together with some Rh2O3 and Rh. The metallic support was oxidized forming the corundum scale and chromium oxides, moreover t-Al2O3 was identified. For the Rh11.0Mg70.0Al19.0 catalyst the inclusion of Rh in the spinel phase decreased its reducibility in the H-2 pretreatment. The reduction continued during catalytic tests by feeding diluted CH4/O-2/He gas mixtures, evidenced by the catalyst activation. While under concentrated gas mixtures the deactivation occurred, probably by oxidation. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000345735200053 |
Publication Date |
2014-09-24 |
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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 |
2155-5435 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.614 |
Times cited |
13 |
Open Access |
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Notes |
; The authors thank the scientists who assisted during the conducted experiments: D. Grolimund and C. N. Borca for the mu XRF/XRPD experiments performed at MicroXAS Beamline of SLS, M. Janousch for the mu XRF/XANES experiments at Phoenix Beamline of the SLS, M. Salome for the mu XRE/XANES experiments at ID21 Beamline of the ESRF, and I. Guerra for the FEG-SEM/EDS experiments at Granada University. Thanks must go to Porvair for supplying FeCrAlloy foams. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, I) is gratefully acknowledged. ; |
Approved |
Most recent IF: 10.614; 2014 IF: 9.312 |
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Call Number |
UA @ admin @ c:irua:122215 |
Serial |
5820 |
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Permanent link to this record |
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Author |
Basile, F.; Benito, P.; Bugani, S.; de Nolf, W.; Fornasari, G.; Janssens, K.; Morselli, L.; Scavetta, E.; Tonelli, D.; Vaccari, A. |
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Title |
Combined use of synchrotron-radiation-based imaging techniques for the characterization of structured catalysts |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
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Volume |
20 |
Issue |
23 |
Pages |
4117-4126 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Active-phase-coated metallic supports as structured catalysts are gaining attention in endothermic and exothermic processes because they improve heat transfer. The deposition of a well-adhered and stable catalyst layer on the metallic support constitutes an important feature for the successful application of the final material. In this work, coating of FeCrAlY foams is performed by a one-step electrosynthesis-deposition of hydrotalcite-type compounds, precursors of catalysts active in endothermic steam methane reforming. The catalysts are studied at different length scales by using, for the first time, a combination of several techniques: SEM/EDS and X-ray fluorescence, X-ray powder diffraction and absorption-tomography experiments on the micro- and nanoscales at a synchrotron facility. The results show that the morphology of the coating depends on the synthesis conditions and that the catalyst may be described as Ni metal crystallites dispersed on γ-Al2O3, homogeneously coating the FeCrAlY foam. |
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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 |
000285392900010 |
Publication Date |
2010-09-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1616-301x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
12.124 |
Times cited |
24 |
Open Access |
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Notes |
; The authors give thanks to Dr. Cloetens, for helping during the absorption tomography experiments, performed at ID19 of the ESRF; and P. Blauet and R. Toucolou, for helping during the mu-XRF/XRPD and nano-XRF experiments at ID22 and ID22-NI of the ESRF. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, Italy) is gratefully acknowledged. ; |
Approved |
Most recent IF: 12.124; 2010 IF: 8.508 |
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Call Number |
UA @ admin @ c:irua:85834 |
Serial |
5525 |
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Permanent link to this record |
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Author |
Hillen, M.; Legrand, S.; Dirkx, Y.; Janssens, K.; van der Snickt, G.; Caen, J.; Steenackers, G. |
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Title |
Cluster analysis of IR thermography data for differentiating glass types in historical leaded-glass windows |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Applied Sciences-Basel |
Abbreviated Journal |
Appl Sci-Basel |
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Volume |
10 |
Issue |
12 |
Pages |
4255-13 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp Cultural Heritage Sciences (ARCHES); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Infrared thermography is a fast, non-destructive and contactless testing technique which is increasingly used in heritage science. The aim of this study was to assess the ability of infrared thermography, in combination with a data clustering approach, to differentiate between the different types of historical glass that were included in a colorless leaded-glass windows during previous restoration interventions. Inspection of the thermograms and the application of two data mining techniques on the thermal data, i.e., k-means clustering and hierarchical clustering, allowed identifying different groups of window panes that show a different thermal behavior. Both clustering approaches arrive at similar groupings of the glass with a clear separation of three types. However, the lead cames that hold the glass panes appear to have a substantial impact on the thermal behavior of the surrounding glass, thus preventing classification of the smallest glass panes. For the larger panes, this was not a critical issue as the center of the glass remained unaffected. Subtle visual color differences between panes, implying a variation in coloring metal ions, was not always distinguished by IRT. Nevertheless, data clustering assisted infrared thermography shows potential as an efficient and swift method for documenting the material intervention history of leaded-glass windows during or in preparation of conservation treatments. |
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Place of Publication |
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Wos |
000549351800001 |
Publication Date |
2020-06-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2076-3417 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.7 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 2.7; 2020 IF: 1.679 |
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Call Number |
UA @ admin @ c:irua:170012 |
Serial |
7674 |
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Permanent link to this record |
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Author |
Koirala, B.; Rasti, B.; Bnoulkacem, Z.; de Lima Ribeiro, A.; Madriz, Y.; Herrmann, E.; Gestels, A.; De Kerf, T.; Lorenz, S.; Fuchs, M.; Janssens, K.; Steenackers, G.; Gloaguen, R.; Scheunders, P. |
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Title |
A multisensor hyperspectral benchmark dataset for unmixing of intimate mixtures |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
IEEE sensors journal |
Abbreviated Journal |
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Volume |
24 |
Issue |
4 |
Pages |
4694-4710 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Vision lab; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
Optical hyperspectral cameras capture the spectral reflectance of materials. Since many materials behave as heterogeneous intimate mixtures with which each photon interacts differently, the relationship between spectral reflectance and material composition is very complex. Quantitative validation of spectral unmixing algorithms requires high-quality ground truth fractional abundance data, which are very difficult to obtain. In this work, we generated a comprehensive laboratory ground truth dataset of intimately mixed mineral powders. For this, five clay powders (Kaolin, Roof clay, Red clay, mixed clay, and Calcium hydroxide) were mixed homogeneously to prepare 325 samples of 60 binary, 150 ternary, 100 quaternary, and 15 quinary mixtures. Thirteen different hyperspectral sensors have been used to acquire the reflectance spectra of these mixtures in the visible, near, short, mid, and long-wavelength infrared regions (350-15385) nm. Overlaps in wavelength regions due to the operational ranges of each sensor and variations in acquisition conditions resulted in a large amount of spectral variability. Ground truth composition is given by construction, but to verify that the generated samples are sufficiently homogeneous, XRD and XRF elemental analysis is performed. We believe these data will be beneficial for validating advanced methods for nonlinear unmixing and material composition estimation, including studying spectral variability and training supervised unmixing approaches. The datasets can be downloaded from the following link: https://github.com/VisionlabHyperspectral/Multisensor_datasets. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
001173599400063 |
Publication Date |
2023-12-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1530-437x; 1558-1748 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4.3 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 4.3; 2024 IF: 2.512 |
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Call Number |
UA @ admin @ c:irua:203094 |
Serial |
9059 |
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Permanent link to this record |
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Author |
van der Snickt, G.; Dubois, H.; Sanyova, J.; Legrand, S.; Coudray, A.; Glaude, C.; Postec, M.; van Espen, P.; Janssens, K. |
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Title |
Large-area elemental imaging reveals Van Eyck's original paint layers on the Ghent altarpiece (1432), rescoping its conservation treatment |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
56 |
Issue |
17 |
Pages |
4797-4801 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A combination of large-scale and micro-scale elemental imaging, yielding elemental distribution maps obtained by, respectively non-invasive macroscopic X-ray fluorescence (MA-XRF) and by secondary electron microscopy/energy dispersive X-ray analysis (SEM-EDX) and synchrotron radiation-based micro-XRF (SR m-XRF) imaging was employed to reorient and optimize the conservation strategy of van Eyck's renowned Ghent Altarpiece. By exploiting the penetrative properties of X-rays together with the elemental specificity offered by XRF, it was possible to visualize the original paint layers by van Eyck hidden below the overpainted surface and to simultaneously assess their condition. The distribution of the high-energy Pb-L and Hg-L emission lines revealed the exact location of hidden paint losses, while Fe-K maps demonstrated how and where these lacunae were filled-up using an iron-containing material. The chemical maps nourished the scholarly debate on the overpaint removal with objective, chemical arguments, leading to the decision to remove all skillfully applied overpaints, hitherto interpreted as work by van Eyck. MA-XRF was also employed for monitoring the removal of the overpaint during the treatment phase. To gather complementary information on the in-depth layer build-up, SEM-EDX and SR mu-XRF imaging was used on paint cross sections to record microscale elemental maps. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Wos |
000398576000019 |
Publication Date |
2017-03-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
11 |
Open Access |
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Notes |
; This research was supported by the Baillet Latour fund, the Belgian Science Policy Office (Projects MO/39/011) and the Gieskes-Strijbis fund. The authors are also indebted to the BOF-GOA SOLAR Paint project of the University of Antwerp Research Council. The church wardens of the cathedral of St. Bavo and their chairman L. Collin are acknowledged for this agreeable collaboration. We also wish to thank conservators L. Depuydt, B. De Volder, F. Rosier, N. Laquiere and G. Steyaert as well as the members of the international committee. We are indebted to Prof. Em. A. Van Grevenstein-Kruse. ; |
Approved |
Most recent IF: 11.994 |
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Call Number |
UA @ admin @ c:irua:142376 |
Serial |
5688 |
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Permanent link to this record |
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Author |
Kempenaers, L.; Janssens, K.; Vincze, L.; Vekemans, B.; Somogyi, A.; Drakopoulos, M.; Simionovici, A.S.; Adams, F. |
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Title |
A Monte Carlo model for studying the microheterogeneity of trace elements in reference materials by means of synchrotron microscopic X-ray fluorescence |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
74 |
Issue |
19 |
Pages |
5017-5026 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
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Wos |
000178418100031 |
Publication Date |
2002-09-30 |
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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 |
21 |
Open Access |
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Notes |
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Approved |
Most recent IF: 6.32; 2002 IF: 5.094 |
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Call Number |
UA @ admin @ c:irua:39871 |
Serial |
5734 |
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Permanent link to this record |
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Author |
Rossbach, L.M.; Brede, D.A.; Nuyts, G.; Cagno, S.; Olsson, R.M.S.; Oughton, D.H.; Falkenberg, G.; Janssens, K.; Lind, O.C. |
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Title |
Synchrotron XRF analysis identifies cerium accumulation colocalized with pharyngeal deformities in CeO₂ NP-exposed caenorhabditis elegans |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Environmental science and technology |
Abbreviated Journal |
Environ Sci Technol |
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Volume |
56 |
Issue |
8 |
Pages |
5081-5089 |
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Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
A combination of synchrotron radiation-based elementalimaging, in vivo redox status analysis, histology, and toxic responses was usedto investigate the uptake, biodistribution, and adverse effects of Cenanoparticles (CeO2NP; 10 nm; 0.5-34.96 mg Ce L-1) or Ce(NO3)3(2.3-26 mg Ce L-1)inCaenorhabditis elegans. Elemental mapping of theexposed nematodes revealed Ce uptake in the alimentary canal prior todepuration. Retention of CeO2NPs was low compared to that of Ce(NO3)3in depurated individuals. X-rayfluorescence (XRF) mapping showed that Cetranslocation was confined to the pharyngeal valve and foregut. Ce(NO3)3exposure significantly decreased growth, fertility, and reproduction, causedslightly reduced fecundity. XRF mapping and histological analysis revealedsevere tissue deformities colocalized with retained Ce surrounding thepharyngeal valve. Both forms of Ce activated the sod-1 antioxidant defense,particularly in the pharynx, whereas no significant effects on the cellular redox balance were identified. The CeO2NP-induceddeformities did not appear to impair the pharyngeal function or feeding ability as growth effects were restricted to Ce(NO3)3exposure. The results demonstrate the utility of integrated submicron-resolution SR-based XRF elemental mapping of tissue-specificdistribution and adverse effect analysis to obtain robust toxicological evaluations of metal-containing contaminants. |
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Place of Publication |
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Wos |
000793137500039 |
Publication Date |
2022-04-04 |
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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 |
0013-936x; 1520-5851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 11.4 |
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Call Number |
UA @ admin @ c:irua:188662 |
Serial |
7216 |
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Permanent link to this record |
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Author |
Byrnes, I.; Rossbach, L.M.; Brede, D.A.; Grolimund, D.; Sanchez, D.F.; Nuyts, G.; Cuba, V.; Reinoso-Maset, E.; Salbu, B.; Janssens, K.; Oughton, D.; Scheibener, S.; Teien, H.-C.; Lind, O.C. |
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Title |
Synchrotron-based X-ray fluorescence imaging elucidates uranium toxicokinetics in Daphnia magna |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
ACS nano |
Abbreviated Journal |
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Volume |
17 |
Issue |
6 |
Pages |
5296-5305 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
A combination of synchrotron-based elemental anal-ysis and acute toxicity tests was used to investigate the biodistribution and adverse effects in Daphnia magna exposed to uranium nanoparticle (UNP, 3-5 nm) suspensions or to uranium reference (Uref) solutions. Speciation analysis revealed similar size distributions between exposures, and toxicity tests showed com-parable acute effects (UNP LC50: 402 mu g L-1 [336-484], Uref LC50: 268 mu g L-1 [229-315]). However, the uranium body burden was 3 -to 5-fold greater in UNP-exposed daphnids, and analysis of survival as a function of body burden revealed a similar to 5-fold higher specific toxicity from the Uref exposure. High-resolution X-ray fluorescence elemental maps of intact, whole daphnids from sublethal, acute exposures of both treatments revealed high uranium accumulation onto the gills (epipodites) as well as within the hepatic ceca and the intestinal lumen. Uranium uptake into the hemolymph circulatory system was inferred from signals observed in organs such as the heart and the maxillary gland. The substantial uptake in the maxillary gland and the associated nephridium suggests that these organs play a role in uranium removal from the hemolymph and subsequent excretion. Uranium was also observed associated with the embryos and the remnants of the chorion, suggesting uptake in the offspring. The identification of target organs and tissues is of major importance to the understanding of uranium and UNP toxicity and exposure characterization that should ultimately contribute to reducing uncertainties in related environmental impact and risk assessments. |
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Place of Publication |
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Wos |
000960129800001 |
Publication Date |
2023-03-15 |
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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 |
1936-0851 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
17.1 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 17.1; 2023 IF: 13.942 |
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Call Number |
UA @ admin @ c:irua:196061 |
Serial |
8631 |
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Permanent link to this record |
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Author |
Tadić, M.; Peeters, F.M.; Janssens, K.L.; Korkusinski, M.; Hawrylak, P. |
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Title |
Strain and band edges in single and coupled cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
92 |
Issue |
10 |
Pages |
5819-5829 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A comparative study is made of the strain distribution in cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots as obtained from isotropic elasticity theory, the anisotropic continuum mechanical model, and from atomistic calculations. For the isotropic case, the recently proposed approach [J. H. Davies, J. Appl. Phys. 84, 1358 (1998)] is used, while the finite-element method, the valence force field method, and Stillinger-Weber potentials are employed to calculate the strain in anisotropic structures. We found that all four methods result in strain distributions of similar shapes, but with notable quantitative differences inside the dot and near the disk-matrix boundary. The variations of the diagonal strains with the height of the quantum dot, with fixed radius, as calculated from all models, are almost linear. Furthermore, the energies of the band edges in the two types of quantum dots are extracted from the multiband effective-mass theory by inserting the strain distributions as obtained by the four models. We demonstrated that all strain models produce effective potentials for the heavy and light holes which agree very well inside the dot. A negligible anisotropy of all normal strains in the (x,y) plane is found, which, providing the axial symmetry of the kinetic part of the multiband effective-mass Hamiltonian, justifies the use of the axial approximation. Strain propagation along the vertical direction is also considered with the aim to study the influence of strain on the electron coupling in stacks of quantum dots. We found that the interaction between the strain fields of the individual quantum dots makes the effective quantum wells for the electrons in the conduction band shallower, thereby counteracting the quantum mechanical coupling. (C) 2002 American Institute of Physics. |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000178987200036 |
Publication Date |
2002-11-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
73 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 2002 IF: 2.281 |
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Call Number |
UA @ lucian @ c:irua:103327 |
Serial |
3164 |
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Permanent link to this record |
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Author |
Koirala, B.; Rasti, B.; Bnoulkacem, Z.; De Lima Ribeiro, A.; Madriz, Y.; Herrmann, E.; Gestels, A.; De Kerf, T.; Janssens, K.; Steenackers, G.; Gloaguen, R.; Scheunders, P. |
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Title |
An extensive multisensor hyperspectral benchmark datasets of intimate mixtures of mineral powders |
Type |
P1 Proceeding |
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Year |
2023 |
Publication |
IEEE International Geoscience and Remote Sensing Symposium proceedings
T2 – IGARSS 2023 – 2023 IEEE International Geoscience and Remote Sensing Symposium, 16-21 July 2023, Pasadena, CA, USA |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
5890-5893
T2 - IGARSS 2023 - 2023 IEEE Internation |
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Keywords |
P1 Proceeding; Economics; Vision lab; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
Since many materials behave as heterogeneous intimate mixtures with which each photon interacts differently, the relationship between spectral reflectance and material composition is very complex. Quantitative validation of spectral unmixing algorithms requires high-quality ground truth fractional abundance data, which are very difficult to obtain.In this work, we generated a comprehensive hyperspectral dataset of intimate mineral powder mixtures by homogeneously mixing five different clay powders (Kaolin, Roof clay, Red clay, mixed clay, and Calcium hydroxide). In total 325 samples were prepared. Among the 325 samples, 60 mixtures were binary, 150 were ternary, 100 were quaternary, and 15 were quinary. For each mixture (and pure clay powder), reflectance spectra are acquired by 13 different sensors, with a broad wavelength range between the visible and the long-wavelength infrared regions (i.e., between 350 nm and 15385 nm) and with a large variation in sensor types, platforms, and acquisition conditions. We will make this dataset public, to be used by the community for the validation of nonlinear unmixing methodologies (https://github.com/VisionlabUA/Multisensor_datasets) |
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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 |
001098971606002 |
Publication Date |
2023-10-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
979-83-503-2010-7 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:201596 |
Serial |
9035 |
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Permanent link to this record |
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Author |
Avranovich Clerici, E.; De Meyer, S.; Vanmeert, F.; Legrand, S.; Monico, L.; Miliani, C.; Janssens, K. |
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Title |
Multi-scale X-ray imaging of the pigment discoloration processes triggered by chlorine compounds in the Upper Basilica of Saint Francis of Assisi |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Molecules: a journal of synthetic chemistry and natural product chemistry |
Abbreviated Journal |
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Volume |
28 |
Issue |
16 |
Pages |
6106-6123 |
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Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
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Abstract |
In this paper, the chromatic alteration of various types of paints, present on mural painting fragments derived from the vaults of The Upper Basilica of Saint Francis of Assisi in Italy (12th-13th century), is studied using synchrotron radiation. Six painted mural fragments, several square centimeters in size, were available for analysis, originating from the ceiling paintings attributed to Cimabue and Giotto; they correspond to originally white, blue/green, and brown/yellow/orange areas showing discoloration. As well as collecting macroscopic X-ray fluorescence and diffraction maps from the entire fragments in the laboratory and at the SOLEIL synchrotron, corresponding paint cross-sections were also analyzed using microscopic X-ray fluorescence and powder diffraction mapping at the PETRA-III synchrotron. Numerous secondary products were observed on the painted surfaces, such as (a) copper tri-hydroxychloride in green/blue areas; (b) corderoite and calomel in vermillion red/cinnabar-rich paints; (c) plattnerite and/or scrutinyite assumed to be oxidation products of (hydro)cerussite (2PbCO(3)center dot Pb(OH)(2)) in the white areas, and (d) the calcium oxalates whewellite and weddellite. An extensive presence of chlorinated metal salts points to the central role of chlorine-containing compounds during the degradation of the 800-year-old paint, leading to, among other things, the formation of the rare mineral cumengeite (21PbCl(2)center dot 20Cu(OH) (2) center dot 6H(2)O). |
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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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Language |
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Wos |
001056388600001 |
Publication Date |
2023-08-17 |
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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 |
1420-3049 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
4.6 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 4.6; 2023 IF: 2.861 |
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Call Number |
UA @ admin @ c:irua:199265 |
Serial |
8902 |
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Permanent link to this record |