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Author |
Anaf, W.; Trashin, S.; Schalm, O.; van Dorp, D.; Janssens, K.; De Wael, K. |
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Title |
Electrochemical photodegradation study of semiconductor pigments : influence of environmental parameters |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume  |
86 |
Issue |
19 |
Pages |
9742-9748 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
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Abstract |
Chemical transformations in paintings often induce discolorations, disturbing the appearance of the image. For an appropriate conservation of such valuable and irreplaceable heritage objects, it is important to have a good know-how on the degradation processes of the (historical) materials: which pigments have been discolored, what are the responsible processes, and which (environmental) conditions have the highest impact on the pigment degradation and should be mitigated. Pigment degradation is already widely studied, either by analyzing historical samples or by accelerated weathering experiments on dummies. However, in historic samples several processes may have taken place, increasing the complexity of the current state, while aging experiments are time-consuming due to the often extended aging period. An alternative method is proposed for a fast monitoring of degradation processes of semiconductor pigments, using an electrochemical setup mimicking the real environment and allowing the identification of harmful environmental parameters for each pigment. Examples are given for the pigments cadmium yellow (CdS) and vermilion (α-HgS). |
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Wos |
000343017100058 |
Publication Date |
2014-08-27 |
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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 |
18 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 6.32; 2014 IF: 5.636 |
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Call Number |
UA @ admin @ c:irua:118834 |
Serial |
5593 |
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Author |
Kontozova-Deutsch, V.; Deutsch, F.; Bencs, L.; Krata, A.; Van Grieken, R.; De Wael, K. |
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Title |
Optimization of the ion chromatographic quantification of airborne fluoride, acetate and formate in the Metropolitan Museum of Art, New York |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
Talanta |
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Volume |
86 |
Issue |
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Pages |
372-376 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Ion chromatographic (IC) methods have been compared in order to achieve an optimal separation of fluoride, acetate and formate under various elution conditions on two formerly introduced analytical columns (i and ii) and a novel one (iii): (i) an IonPac AS14 (250 mm × 4 mm I.D.), (ii) Allsep A-2 (150 mm × 4.6 mm I.D.), and (iii) an IC SI-50 4E (250 mm (length) × 4 mm (internal diameter – I.D.)). The IC conditions for the separation of the anions concerned were optimized on the IC SI-50 4E column. A near baseline separation of these anions was attained on the IonPac AS14, whereas the peaks of fluoride and acetate could not be resolved on the Allsep A-2. A baseline separation for the three anions was achieved on the IC SI-50 4E column, when applying an eluent mixture of 3.2 mmol/L Na2CO3 and 1.0 mmol/L NaHCO3 with a flow rate of 1.0 mL/min. The highest precision of 1.7, 3.0 and 2.8% and the best limits of detection (LODs) of 0.014, 0.22 and 0.17 mg/L for fluoride, acetate and formate, respectively, were obtained with the IC SI-50 4E column. Hence, this column was applied for the determination of the acetic and formic acid contents of air samples taken by means of passive gaseous sampling at the Metropolitan Museum of Art in New York, USA. Atmospheric concentrations of acetic and formic acid up to 1050 and 450 μg/m3, respectively, were found in non-aerated showcases of the museum. In galleries and outdoors, rather low levels of acetic and formic acid were detected with average concentrations of 50 and 10 μg/m3, respectively. The LOD data of acetate and formate on the IC SI-50 4E column correspond to around 0.5 μg/m3 for both acetic and formic acid in air samples. |
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Wos |
000298126300048 |
Publication Date |
2011-09-24 |
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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 |
0039-9140; 1873-3573 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.162 |
Times cited |
19 |
Open Access |
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Notes |
; The authors gratefully acknowledge the support of Marco Leona and the staff of the Metropolitan Museum of Art in New York during the sampling campaigns. The technical assistance and advice by Dr. Takashi Kotsuka and Shodex Benelux are acknowledged as well. ; |
Approved |
Most recent IF: 4.162; 2011 IF: 3.794 |
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Call Number |
UA @ admin @ c:irua:92066 |
Serial |
5762 |
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Author |
Harlay, J.; Borges, A.V.; van der Zee, C.; Delille, B.; Godoi, R.H.M.; Schiettecatte, L.-S.; Roevros, N.; Aerts, K.; Lapernat, P.-E.; Rebreanu, L.; Groom, S.; Daro, M.-H.; Van Grieken, R.; Chou, L. |
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Title |
Biogeochemical study of a coccolithophore bloom in the northern Bay of Biscay (NE Atlantic Ocean) in June 2004 |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Progress in oceanography |
Abbreviated Journal |
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Volume |
86 |
Issue |
3/4 |
Pages |
317-336 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The present paper synthesizes data obtained during a multidisciplinary cruise carried out in June 2004 at the continental margin of the northern Bay of Biscay. The data-set allows to describe the different stages of a coccolithophore bloom dominated by Emiliania huxleyi. The cruise was carried out after the main spring phytoplankton bloom that started in mid-April and peaked in mid-May. Consequently, low phosphate (PO4 < 0.2 μM) and silicate (DSi < 2.0 μM) concentrations, low partial pressure of carbon dioxide (pCO2) and high calcite saturation degree in surface waters combined with thermal stratification, probably favoured the blooming of coccolithophores. During the period of the year our cruise was carried out, internal tides induce enhanced vertical mixing at the continental shelf break leading to the injection of inorganic nutrients to surface waters that probably trigger the bloom. The bloom developed as the water-column stratified and as the water mass was advected over the continental shelf, following the general residual circulation in the area. The most developed phase of the bloom was sampled in a remote sensed high reflectance (HR) patch over the continental shelf that was characterized by low chlorophyll-a (Chl-a) concentration in surface waters (<1.0 μg L−1), high particulate inorganic carbon (PIC) concentration (not, vert, similar8 μmol L−1) and coccolithophore abundance up to 57 × 106 cells L−1. Transparent exopolymer particles (TEP) concentrations ranged between 15 and 75 μg C L−1 and carbon content of TEP represented up to 26% of the particulate organic carbon (POC; maximum concentration of 15.5 μmol L−1 in the upper 40 m). Integrated primary production (PP) ranged between 210 and 680 mg C m−2 d−1 and integrated calcification (CAL) ranged between 14 and 140 mg C m−2 d−1, within the range of PP and CAL values previously reported during coccolithophore blooms in open and shelf waters of the North Atlantic Ocean. Bacterial protein production (BPP) measurements in surface waters (0.30.7 μg C L−1 h−1) were much higher than those reported during early phases of coccolithophore blooms in natural conditions, but similar to those during peak and declining coocolithophorid blooms reported in mesocosms. Total alkalinity anomalies with respect to conservative mixing (ΔTA) down to −49 μmol kg−1 are consistent with the occurrence of biogenic precipitation of calcite, while pCO2 remained 15107 μatm lower than atmospheric equilibrium (372 μatm). The correlation between ΔTA and pCO2 suggested that pCO2 increased in part due to calcification, but this increase was insufficient to overcome the background under-saturation of CO2. This is related to the biogeochemical history of the water masses due to net carbon fixation by the successive phytoplankton blooms in the area prior to the cruise, hence, the investigated area remained a sink for atmospheric CO2 despite calcification. |
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Wos |
000281937800001 |
Publication Date |
2010-04-20 |
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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 |
0079-6611 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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no |
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Call Number |
UA @ admin @ c:irua:84236 |
Serial |
7560 |
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Author |
Monico, L.; Janssens, K.; Miliani, C.; Brunetti, B.G.; Vagnini, M.; Vanmeert, F.; Falkenberg, G.; Abakumov, A.; Lu, Y.; Tian, H.; Verbeeck, J.; Radepont, M.; Cotte, M.; Hendriks, E.; Geldof, M.; van der Loeff, L.; Salvant, J.; Menu, M.; |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 3 : synthesis, characterization, and detection of different crystal forms of the chrome yellow pigment |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
85 |
Issue |
2 |
Pages |
860-867 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The painter, Vincent van Gogh, and some of his contemporaries frequently made use of the pigment chrome yellow that is known to show a tendency toward darkening. This pigment may correspond to various chemical compounds such as PbCrO4 and PbCr1-xSxO4, that may each be present in various crystallographic forms with different tendencies toward degradation. Investigations by X-ray diffraction (XRD), mid-Fourier Transform infrared (FTIR), and Raman instruments (benchtop and portable) and synchrotron radiation-based micro-XRD and X-ray absorption near edge structure spectroscopy performed on oil-paint models, prepared with in-house synthesized PbCrO4 and PbCr1-xSxO4, permitted us to characterize the spectroscopic features of the various forms. On the basis of these results, an extended study has been carried out on historic paint tubes and on embedded paint microsamples taken from yellow-orange/pale yellow areas of 12 Van Gogh paintings, demonstrating that Van Gogh effectively made use of different chrome yellow types. This conclusion was also confirmed by in situ mid-FTIR investigations on Van Goghs Portrait of Gauguin (Van Gogh Museum, Amsterdam). |
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Place of Publication |
Washington, D.C. |
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Wos |
000313668400031 |
Publication Date |
2012-10-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700;1520-6882; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
79 |
Open Access |
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Notes |
Goa; Fwo |
Approved |
Most recent IF: 6.32; 2013 IF: 5.825 |
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Call Number |
UA @ lucian @ c:irua:108707UA @ admin @ c:irua:108707 |
Serial |
631 |
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Author |
Monico, L.; Janssens, K.; Miliani, C.; van der Snickt, G.; Brunetti, B.G.; Guidi, M.C.; Radepont, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods : 4 : artificial aging of model samples of co-precipitates of lead chromate and lead sulfate |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
85 |
Issue |
2 |
Pages |
860-867 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Previous investigations about the darkening of chrome yellow pigments revealed that this form of alteration is attributable to a reduction of the original Cr(VI) to Cr(III), and that the presence of sulfur-containing compounds, most often sulfates, plays a key role during this process. We recently demonstrated that different crystal forms of chrome yellow pigments (PbCrO4 and PbCr1xSxO4) are present in paintings by Vincent van Gogh. In the present work, we show how both the chemical composition and the crystalline structure of lead chromate-based pigments influence their stability. For this purpose, oil model samples made with in-house synthesized powders of PbCrO4 and PbCr1xSxO4 were artificially aged and characterized. We observed a profound darkening only for those paint models made with PbCr1xSxO4, rich in SO42 (x ≥ 0.4), and orthorhombic phases (>30 wt %). Cr and S K-edge micro X-ray absorption near edge structure investigations revealed in an unequivocal manner the formation of up to about 60% of Cr(III)-species in the outer layer of the most altered samples; conversely, independent of the paint models chemical composition, no change in the S-oxidation state was observed. Analyses employing UVvisible diffuse reflectance and Fourier transform infrared spectroscopy were performed on unaged and aged model samples in order to obtain additional information on the physicochemical changes induced by the aging treatment. |
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Wos |
000313668400032 |
Publication Date |
2012-10-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
49 |
Open Access |
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Notes |
; This research was supported by grants from ESRF (experiment EC-799), the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16), and the BELSPO-SDD S2-ART (SD/RI/04) project. The text also presents results from GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and FWO (Brussels, Belgium) projects G.0704.08 and G.01769.09. The EU FP7 programme CHARISMA (Grant Agreement 228330) and MIUR (PRIN08, Materiali e sistemi innovativi per la conservazione dell'arte contemporanea 2008 FFXXN9) are also acknowledged. ; |
Approved |
Most recent IF: 6.32; 2013 IF: 5.825 |
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Call Number |
UA @ admin @ c:irua:110471 |
Serial |
5569 |
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Author |
György, K.; Ajtony, Z.; van Meel, K.; Van Grieken, R.; Czitrovszky, A.; Bencs, L. |
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Title |
Fast heating induced impulse halogenation of refractory sample components in electrothermal atomic absorption spectrometry by direct injection of a liquid halogenating agent |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
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Volume |
85 |
Issue |
3 |
Pages |
1253-1259 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A novel electrothermal atomic absorption spectrometry (ETAAS) method was developed for the halogenation of refractory sample components (Er, Nd and Nb) of lithium niobate (LiNbO3) and bismuth tellurite (Bi2TeO5) optical single crystals to overcome memory effects and carry-over. For this purpose, the cleaning step of a regular graphite furnace heating program was replaced with a halogenation cycle. In this cycle, after the graphite tube cooled to room temperature, a 20 μL aliquot of liquid carbon tetrachloride (CCl4) was dispensed with a conventional autosampler into the graphite tube. The CCl4 was partially dried at 80 °C under the mini-flow (40 cm3 min−1) condition of the Ar internal furnace gas (IFG), then the residue was decomposed (pyrolyzed) by fast furnace heating at 19002100 °C under interrupted flow of the IFG. This step was followed by a clean-out stage at 2100 °C under the maximum flow of the IFG. The advantage of the present method is that it does not require any alteration to the graphite furnace gas supply system in contrast to most of the formerly introduced halogenation techniques. The effectiveness of the halogenation method was verified with the determination of Er and Nd dopants in the optical crystals. In these analyses, a sensitivity decrease was observed, which was likely due to the enhanced deterioration of the graphite tube surface. Therefore, the application of mathematical correction (resloping) of the calibration was also required. The calibration curves were linear up to 1.5 and 10 μmol L−1 for Er and Nd, respectively. Characteristic masses of 18 and 241 pg and the limit of detection (LOD) values of 0.017 and 0.27 μmol L−1 were found for Er and Nd, respectively. These LOD data correspond to 0.68 μmol mol−1 Er and 11 μmol mol−1 Nd in solid bismuth tellurite samples. The analytical results were compared with those obtained by a conventional ETAAS method and validated with X-ray fluorescence spectrometry analysis. |
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Wos |
000294092800006 |
Publication Date |
2011-05-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0039-9140; 1873-3573 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:91721 |
Serial |
7960 |
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Author |
Semenov, M.Y.; Spolnik, Z.; Granina, L.; Van Grieken, R. |
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Title |
Ultra-thin window electron probe microanalysis of suspended particles in tributaries of Lake Baikal, Siberia |
Type |
A1 Journal article |
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Year |
2005 |
Publication |
International journal of environmental analytical chemistry |
Abbreviated Journal |
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Volume |
85 |
Issue |
6 |
Pages |
377-386 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Wos |
000229611800003 |
Publication Date |
2007-07-07 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
0306-7319 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:52360 |
Serial |
8701 |
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Author |
Kukhlevsky, S.V.; Mechler, M.; Samek, O.; Janssens, K. |
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Title |
Analytical model of the enhanced light transmission through subwavelength metal slits: Green's function formalism versus Rayleigh's expansion |
Type |
A1 Journal article |
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Year |
2006 |
Publication |
Applied physics B : lasers and optics |
Abbreviated Journal |
Appl Phys B-Lasers O |
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Volume |
84 |
Issue |
1/2 |
Pages |
19-24 |
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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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Place of Publication |
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Language |
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Wos |
000238828700004 |
Publication Date |
2006-05-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0946-2171 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.696 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.696; 2006 IF: 2.023 |
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Call Number |
UA @ admin @ c:irua:59635 |
Serial |
5472 |
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Author |
Pilehvar, S.; Mehta, J.; Dardenne, F.; Robbens, J.; Blust, R.; De Wael, K. |
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Title |
Aptasensing of chloramphenicol in the presence of its analogues : reaching the maximum residue limit |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
84 |
Issue |
15 |
Pages |
6753-6758 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A novel label-free folding induced aptamer-based electrochemical biosensor for the detection of chloramphenicol (CAP) in the presence of its analogues has been developed. CAP is a broad-spectrum antibiotic which has lost its favor due to its serious adverse toxic effects on human health. Aptamers are artificial nucleic acid ligands (ssDNA or RNA) able to specifically recognize a target such as CAP. In this article, the aptamers are fixed onto a gold electrode surface by a self-assembly approach. In the presence of CAP, the unfolded ssDNA on the electrode surface changes to a hairpin structure bringing the target molecules close to the surface and trigger electron transfer. Detection limits were determined to be 1.6×10-9 mol L-1. In addition, thiamphenicol (TAP) and florfenicol (FF), antibiotics with a similar structure to CAP, did not influence the performance of the aptasensor, suggesting a good selectivity of the CAP-aptasensor. Simplicity and lower detection limit (because of the home-selected aptamers) make that the electrochemical aptasensor is suitable for practical use in the detection of CAP in milk samples. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
000307159200069 |
Publication Date |
2012-06-20 |
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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 |
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 |
68 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 6.32; 2012 IF: 5.695 |
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Call Number |
UA @ admin @ c:irua:98816 |
Serial |
5477 |
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Author |
van der Snickt, G.; Janssens, K.; Dik, J.; de Nolf, W.; Vanmeert, F.; Jaroszewicz, J.; Cotte, M.; Falkenberg, G.; Van der Loeff, L. |
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Title |
Combined use of synchrotron radiation based micro-X-ray fluorescence, micro-X-ray diffraction, micro-X-ray absorption near-edge, and micro-fourier transform infrared spectroscopies for revealing an alternative degradation pathway of the pigment cadmium yellow in a painting by Van Gogh |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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| |
Volume |
84 |
Issue |
23 |
Pages |
10221-10228 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Over the past years a number of studies have described the instability of the pigment cadmium yellow (CdS). In a previous paper we have shown how cadmium sulfide on paintings by James Ensor oxidizes to CdSO4 center dot H2O. The degradation process gives rise to the fading of the bright yellow color and the formation of disfiguring white crystals that are present on the paint surface in approximately 50 mu m sized globular agglomerations. Here, we study cadmium yellow in the painting “Flowers in a blue vase” by Vincent van Gogh. This painting differs from the Ensor case in the fact that (a) a varnish was superimposed onto the degraded paint surface and (b) the CdS paint area is entirely covered with an opaque crust. The latter obscures the yellow color completely and thus presents a seemingly more advanced state of degradation. Analysis of a cross-sectioned and a crushed sample by combining scanning microscopic X-ray diffraction (mu-XRD), microscopic X-ray absorption near-edge spectroscopy (mu-XANES), microscopic X-ray fluorescence (mu-XRF) based chemical state mapping and scanning microscopic Fourier transform infrared (mu-FT-IR) spectrometry allowed unravelling the complex alteration pathway. Although no crystalline CdSO4 compounds were identified on the Van Gogh paint samples, we conclude that the observed degradation was initially caused by oxidation of the original CdS pigment, similar as for the previous Ensor case. However, due to the presence of an overlying varnish containing lead-based driers and oxalate ions, secondary reactions took place. In particular, it appears that upon the photoinduced oxidation of its sulfidic counterion, the Cd2+ ions reprecipitated at the paint/varnish interface after having formed a complex with oxalate ions that themselves are considered to be degradation products of the resin and/or oil in the varnish. The SO42- anions, for their part, found a suitable reaction partner in Pb2+ ions stemming from a dissolved lead-based siccative that was added to the varnish to promote its drying. The resulting opaque anglesite compound in the varnish, in combination with the underlying CdC2O4 layer at the paint/varnish interface, account for the orange-gray crust that is disfiguring the painting on a macroscopic level. In this way, the results presented in this paper demonstrate how, through a judicious combined use of several microanalytical methods with speciation capabilities, many new insights can be obtained from two minute, but highly complex and heterogeneous paint samples. |
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Wos |
000311815300013 |
Publication Date |
2012-08-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
59 |
Open Access |
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Notes |
; This research was supported by BELSPO via the Interuniversity Attraction Poles Programme (IUAP VI/16) and the S2-ART project (SD/RI/04A) and funded by Grants from the ESRF (EC-442) and PETRA-III (I-20120312 EC). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Kroller-Muller Museum and painting conservators Margje Leeuwestein and Esther Van Duijn are acknowledged for this pleasant cooperation and the authorization for the publication of the images in this article. ; |
Approved |
Most recent IF: 6.32; 2012 IF: 5.695 |
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Call Number |
UA @ admin @ c:irua:105971 |
Serial |
5526 |
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| Permanent link to this record |
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Author |
Cagno, S.; Cosyns, P.; Ceglia, A.; Nys, K.; Janssens, K. |
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Title |
The use of vitrum obsianum in the Roman Empire: some new insights and future prospects |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Periodico di mineralogia |
Abbreviated Journal |
Period Mineral |
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Volume |
84 |
Issue |
3a |
Pages |
465-482 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The research on the use of obsidian in the Mediterranean is extensive but concerns almost exclusively volcanic glass from prehistoric and Bronze Age contexts. The consumption of obsidian during the Roman imperial period, however, has only occasionally received attention. Never a comprehensive account on what the Romans made in vitrum obsianum has been set up, nor have the sources exploited by them been examined. This paper provides a concise overview of the current knowledge on obsidian during the Roman imperial period and offers an introductory outline on potential research. The ancient writers inform us about the use of volcanic glass to create exclusive vessels, gemstones, mirrors and sculpture, but also about the creation of black appearing man-made glass initiated as a cheap and easier workable substitute of obsidian. The archaeological data on the other hand propose a more complex story with the occurrence of obsidian chunks in early Roman secondary glass workshops, and the bulky use of obsidian in late Antiquity to produce tesserae for the creation of wall and vault mosaics. Because it is extremely difficult to visually distinguish natural obsidian from man-made glass imitations we present in this paper data collected by means of non-destructive chemico-physical analyses SEM-EDX, portable X-ray fluorescence (p-XRF) and Raman spectroscopy to easily distinguish man-made glass from natural obsidian. In particular the use of portable instruments makes possible in situ analysis of objects in archaeological depots or museum collections to help defining distribution networks to better understand the shifting consumption patterns in Antiquity. |
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Wos |
000365632500007 |
Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0369-8963 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
0.883 |
Times cited |
2 |
Open Access |
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Notes |
; Our sincere gratitude goes to Cecile Evers and Natacha Masar to have granted permission for studying and analysing various obsidian artefacts within the collections of the Royal Museums of Art and History, Brussels (Belgium). We are also very grateful to Roald Doctor, Daniele Foy and Laudine Robin, respectively for having provided the material from Carthage, for the Sidi Jdidi tessera and Lyon. Our appreciation also goes to Ian Freestone and Andrew Meek respectively for having worked out and provided the internal report on the horse foreleg in the British Museum. Finally we wish to thank Jennifer Price, Maria Grazia Diani respectively for the information on the Stanwick fragment and the piece in the Pogliaghi-Varesse collection. This research was supported by the Hercules Foundation (Brussels) with the grant AUHA09004 and FWO (Brussels, Belgium) projects no. G.0C12.13 and G.01769.09 and partly by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. ; |
Approved |
Most recent IF: 0.883; 2015 IF: 0.464 |
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Call Number |
UA @ admin @ c:irua:130244 |
Serial |
5876 |
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Author |
De Wael, K.; Daems, D.; Van Camp, G.; Nagels, L.J. |
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Title |
The use of potentiometric sensors to study (bio)molecular interactions |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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| |
Volume |
84 |
Issue |
11 |
Pages |
4921-4927 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Potentiometric sensors were used to study molecular interactions in liquid environments, with sensorgram methodology. This is demonstrated with a lipophilic rubber-, and with a collagen based hydrogel sensor coating. The investigated molecules were promazine and tartaric acid respectively. The sensors were placed in a hydrodynamic wall jet system for the recording of sensorgrams. mV sensor responses were first converted to a signal, expressing the concentration of adsorbed organic ions. Using a linearization method, a pseudo first order kinetic model of adsorption was shown to fit the experimental results perfectly. Kass, kon and koff values were calculated.. The technique can be used over 4 decades of concentration, and it is very sensitive to low MW compounds as well as to multiply charged large biomolecules. This study is the first to demonstrate the application of potentiometric sensors as an alternative and complement to SPR methods. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000304783100041 |
Publication Date |
2012-04-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 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 |
10 |
Open Access |
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Notes |
; Financial support for this work was provided by the University of Antwerp by granting D.D. a BOF interdisciplinary research project. We thank J. Everaert for his help in interpreting the results. K.D.W. and D.D. contributed equally to this work. ; |
Approved |
Most recent IF: 6.32; 2012 IF: 5.695 |
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Call Number |
UA @ admin @ c:irua:97520 |
Serial |
5898 |
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Author |
Potgieter-Vermaak, S.S.; Potgieter, J.H.; Kruger, R.A.; Spolnik, Z.; Van Grieken, R. |
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Title |
A characterisation of the surface properties of an ultra fine fly ash (UFFA) used in the polymer industry |
Type |
A1 Journal article |
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Year |
2005 |
Publication |
Fuel |
Abbreviated Journal |
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Volume |
84 |
Issue |
18 |
Pages |
2295-2300 |
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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 |
000233053100002 |
Publication Date |
2005-06-28 |
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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 |
0016-2361 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:54564 |
Serial |
7603 |
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Author |
Seftel, E.M.; Popovici, E.; Mertens, M.; Stefaniak, E.A.; Van Grieken, R.; Cool, P.; Vansant, E.F. |
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Title |
SnIV-containing layered double hydroxides as precursors for nano-sized ZnO/SnO2 photocatalysts |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
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Volume |
84 |
Issue |
3/4 |
Pages |
699-705 |
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Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Sn4+-containing LDH was prepared using the co-precipitation method at constant pH, and characterized using X-ray diffraction, UVvis diffuse reflectance spectroscopy and TG/DTG methods. The obtained product was further exposed to different thermal treatments in order to obtain nano-sized coupled ZnO/SnO2 systems with enhanced photocatalytic performances than the ones obtained by mixing the two semiconductor oxides. The formation of a well-defined ZnO/SnO2 system and the crystallite size, fully investigated using XRD, micro-Raman scattering and UVvis DR techniques, were found to be influenced by the nature of the precursors and the calcination temperature. The photocatalytic activity of the ZnO/SnO2 systems, evaluated for the photodegradation of methyl orange (MO) dye, was studied as a function of the initial pH, catalyst loading and the calcination temperature. The metal dispersion supplied by layered structures proved to be an advantage when preparing coupled ZnO/SnO2 systems, the photocatalytic activity being 2.3 times higher comparing with the physical mixtures performances. The maximum photocatalytic activity of the coupled ZnO/SnO2 system having a layered precursor was observed when using neutral pH, at a catalyst loading of 1 g/L calcined at 600 °C for 4 h. |
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Wos |
000261123600046 |
Publication Date |
2008-06-19 |
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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 |
0926-3373 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:72020 |
Serial |
8651 |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Verbeeck, J.; Tian, H.; Tan, H.; Dik, J.; Radepont, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 1 : artificially aged model samples |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
83 |
Issue |
4 |
Pages |
1214-1223 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1−3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr2O3·2H2O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide], is likely. |
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Place of Publication |
Washington, D.C. |
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Wos |
000287176900011 |
Publication Date |
2011-02-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700;1520-6882; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
113 |
Open Access |
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Notes |
Iuap; Fwo |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
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Call Number |
UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794 |
Serial |
632 |
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Author |
Monico, L.; van der Snickt, G.; Janssens, K.; de Nolf, W.; Miliani, C.; Dik, J.; Radepont, M.; Hendriks, E.; Geldof, M.; Cotte, M. |
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Title |
Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods : 2 : original paint layer samples |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
83 |
Issue |
4 |
Pages |
1224-1231 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The darkening of the original yellow areas painted with the chrome yellow pigment (PbCrO4, PbCrO4·xPbSO4, or PbCrO4·xPbO) is a phenomenon widely observed on several paintings by Vincent van Gogh, such as the famous different versions of Sunflowers. During our previous investigations on artificially aged model samples of lead chromate, we established for the first time that darkening of chrome yellow is caused by reduction of PbCrO4 to Cr2O3·2H2O (viridian green), likely accompanied by the presence of another Cr(III) compound, such as either Cr2(SO4)3·H2O or (CH3CO2)7Cr3(OH)2 [chromium(III) acetate hydroxide]. In the second part of this work, in order to demonstrate that this reduction phenomenon effectively takes place in real paintings, we study original paint samples from two paintings of V. van Gogh. As with the model samples, in view of the thin superficial alteration layers that are present, high lateral resolution spectroscopic methods that make use of synchrotron radiation (SR), such as microscopic X-ray absorption near edge (μ-XANES) and X-ray fluorescence spectrometry (μ-XRF) were employed. Additionally, μ-Raman and mid-FTIR analyses were carried out to completely characterize the samples. On both paint microsamples, the local presence of reduced Cr was demonstrated by means of μ-XANES point measurements. The presence of Cr(III) was revealed in specific areas, in some cases correlated to the presence of Ba(sulfate) and/or to that of aluminum silicate compounds. |
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Place of Publication |
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Wos |
000287176900012 |
Publication Date |
2011-02-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.32 |
Times cited |
84 |
Open Access |
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Notes |
; This research was funded by grants from ESRF (experiment EC-504) and by HASYLAB (experiments 11-20080130 EC and 11-20070157 EC) and was supported by the Interuniversity Attraction Poles Programme-Belgian Science Policy (IUAP VI/16). The text also presents results of GOA “XANES meets ELNES” (Research Fund University of Antwerp, Belgium) and from FWO (Brussels, Belgium) project nos. G.0103.04, G.0689.06, and G.0704.08. The staff of the Van Gogh Museum, Amsterdam, is acknowledged for their agreeable cooperation and for the authorization to publish the images of the paintings in this article. L.M. was financially supported by the Erasmus Placement in the framework of Lifelong Learning Programme (A.Y. 2009-2010). The EU Community's FP7 Research Infrastructures program under the CHARISMA Project (Grant Agreement 228330) is also acknowledged. ; |
Approved |
Most recent IF: 6.32; 2011 IF: 5.856 |
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Call Number |
UA @ admin @ c:irua:88795 |
Serial |
5571 |
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Author |
De Wael, K.; Bashir, Q.; van Vlierberghe, S.; Dubruel, P.; Heering, H.A.; Adriaens, A. |
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Title |
Electrochemical determination of hydrogen peroxide with cytochrome c peroxidase and horse heart cytochrome c entrapped in a gelatin hydrogel |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Bioelectrochemistry: an international journal devoted to electrochemical aspects of biology and biological aspects of electrochemistry |
Abbreviated Journal |
Bioelectrochemistry |
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Volume |
83 |
Issue |
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Pages |
15-18 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A novel and versatile method, based on a membrane-free enzyme electrode in which both the enzyme and a mediator protein are entrapped in a gelatine hydrogel was developed for the fabrication of biosensors. As a proof of principle, we prepared a hydrogen peroxide biosensor by successfully entrapping both horse heart cytochrome c (HHC) and Saccharomyces cerevisae cytochrome c peroxidase (CCP) in a gelatin matrix which is immobilized on a gold electrode. This electrode was first pretreated with 6-mercaptohexanol. The biosensor displayed a rapid response and an expanded linear response range from 0 to 0.3 mM (R = 0.987) with a detection limit of 1 × 10− 5 M in a HEPES buffer solution (pH 7.0). This method of encapsulation is now further investigated for industrial biosensor applications. |
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Wos |
000297962500003 |
Publication Date |
2011-08-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1567-5394 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.346 |
Times cited |
31 |
Open Access |
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Notes |
; Karolien De Wael is grateful to the Research Foundation-Flanders (FWO, Belgium) for her postdoctoral fellowship. ; |
Approved |
Most recent IF: 3.346; 2012 IF: 3.947 |
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Call Number |
UA @ admin @ c:irua:92067 |
Serial |
5589 |
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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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Place of Publication |
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Wos |
000288887700028 |
Publication Date |
2011-03-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0003-2700; 5206-882x |
ISBN |
|
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 |
Darchuk, L.; Gatto Rotondo, G.; Swaenen, M.; Worobiec, A.; Tsybrii, Z.; Makarovska, Y.; Van Grieken, R. |
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| |
Title |
Composition of prehistoric rock-painting pigments from Egypt (Gilf Kébir area) |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Spectrochimica acta: part A: molecular and biomolecular spectroscopy |
Abbreviated Journal |
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| |
Volume |
83 |
Issue |
1 |
Pages |
34-38 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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| |
Abstract |
The composition of rock-painting pigments from Egypt (Gilf Kebia area) has been analyzed by means of molecular spectroscopy such as Fourier transform infrared and micro-Raman spectroscopy and scanning electron microscopy coupled to an energy dispersive X-ray spectrometer and X-ray fluorescence analysis. Red and yellow pigments were recognized as red and yellow ochre with additional rutile. |
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Corporate Author |
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Place of Publication |
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Wos |
000296827600005 |
Publication Date |
2011-07-26 |
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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 |
1386-1425 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
|
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:92015 |
Serial |
7713 |
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| Permanent link to this record |
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Author |
Romero-Pastor, J.; Duran, A.; Rodríguez-Navarro, A.B.; Van Grieken, R.; Cardell, C. |
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| |
Title |
Compositional and quantitative microtextural characterization of historic paintings by micro-X-ray diffraction and Raman microscopy |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Analytical chemistry |
Abbreviated Journal |
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|
| |
Volume |
83 |
Issue |
22 |
Pages |
8420-8428 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
This work shows the benefits of characterizing historic paintings via compositional and microtextural data from micro-X-ray diffraction (μ-XRD) combined with molecular information acquired with Raman microscopy (RM) along depth profiles in paint stratigraphies. The novel approach was applied to identify inorganic and organic components from paintings placed at the 14th century Islamic UniversityMadrasah Yusufiyyain Granada (Spain), the only Islamic University still standing from the time of Al-Andalus (Islamic Spain). The use of μ-XRD to obtain quantitative microtextural information of crystalline phases provided by two-dimensional diffraction patterns to recognize pigments nature and manufacture, and decay processes in complex paint cross sections, has not been reported yet. A simple Nasrid (14th century) palette made of gypsum, vermilion, and azurite mixed with glue was identified in polychromed stuccos. Here also a Christian intervention was found via the use of smalt, barite, hematite, Brunswick green and gold; oil was the binding media employed. On mural paintings and wood ceilings, more complex palettes dated to the 19th century were found, made of gypsum, anhydrite, barite, dolomite, calcite, lead white, hematite, minium, synthetic ultramarine blue, and black carbon. The identified binders were glue, egg yolk, and oil. |
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Corporate Author |
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Place of Publication |
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Editor |
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Wos |
000296830200011 |
Publication Date |
2011-10-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
|
Open Access |
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| |
Notes |
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Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:92679 |
Serial |
7715 |
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| Permanent link to this record |
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Author |
Ameloot, P.C.; Vandeputte, D.F.; Van Grieken, R.E.; Coomans, D. |
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Title |
Localization of lead in cultured tooth germs by laser microprobe micro-analysis |
Type |
A3 Journal article |
| |
Year |
1987 |
Publication |
Proceedings of the Finnish Dental Society |
Abbreviated Journal |
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| |
Volume |
83 |
Issue |
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Pages |
225-236 |
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Keywords |
A3 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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Place of Publication |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0039-551x |
ISBN |
|
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:116799 |
Serial |
8183 |
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| Permanent link to this record |
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Author |
Eyckmans, K.; de Hoog, J.; van der Auwera, L.; Van Grieken, R. |
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Title |
Speciation of aerosols by combining bulk ion chromatography and thin-window electron probe micro analysis |
Type |
A1 Journal article |
| |
Year |
2003 |
Publication |
International journal of environmental analytical chemistry |
Abbreviated Journal |
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| |
Volume |
83 |
Issue |
9 |
Pages |
777-786 |
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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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Place of Publication |
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Editor |
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Wos |
000184457600006 |
Publication Date |
2004-05-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0306-7319 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:43556 |
Serial |
8571 |
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| Permanent link to this record |
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Author |
Jain, R.; Rather, J.A. |
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| |
Title |
Voltammetric determination of antibacterial drug gemifloxacin in solubilized systems at multi-walled carbon nanotubes modified glassy carbon electrode |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Colloids and surfaces: B : biointerfaces |
Abbreviated Journal |
|
|
| |
Volume |
83 |
Issue |
2 |
Pages |
340-346 |
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| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
| |
Abstract |
A sensitive electroanalytical method for determination of gemifloxacin in pharmaceutical formulation has been investigated on the basis of the enhanced electrochemical response at multi-walled carbon nanotubes modified glassy carbon electrode in the presence of CTAB. Solubilized system of different surfactants including SDS, Tween-20 and CTAB were taken for the study of electrochemical behaviour of gemifloxacin at modified electrode. The reduction peak current increases in the presence of CTAB while other surfactants show opposite effect. The modified electrode exhibits catalytic activity, high sensitivity, stability and is applicable over wide range of concentration for the determination of gemifloxacin. The mechanism of electrochemical reduction of gemifloxacin has been proposed on the basis of CV, SWV, DPV and coulometeric techniques. The proposed squarewave voltammetric method shows linearity over the concentration range 2.4715.5 μg/mL. The achieved limits of detection (LOD) and quantification (LOQ) are 0.90 ng/mL and 3.0 ng/mL respectively. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000287268000020 |
Publication Date |
2010-12-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0927-7765 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:98687 |
Serial |
8744 |
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| Permanent link to this record |
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Author |
Dekov, V.; Subramanian, V.; Van Grieken, R. |
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Title |
Chemical composition of riverine suspended matter and sediments from the Indian sub-continent |
Type |
A3 Journal article |
| |
Year |
1999 |
Publication |
Mitteilungen aus dem Geologisch-Paläontologischen Institut der Universität Hamburg |
Abbreviated Journal |
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Volume |
82 |
Issue |
|
Pages |
99-109 |
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Keywords |
A3 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 |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0072-1115 |
ISBN |
|
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:24722 |
Serial |
7655 |
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| Permanent link to this record |
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Author |
Jain, R.; Vikas; Rather, J.A. |
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Title |
Voltammetric behaviour of drotaverine hydrochloride in surfactant media and its enhancement determination in Tween-20 |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Colloids and surfaces: B : biointerfaces |
Abbreviated Journal |
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| |
Volume |
82 |
Issue |
2 |
Pages |
333-339 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
Simple, sensitive and rapid adsorptive voltammetric behaviour of drotaverine hydrochloride onto the HMDE has been explored and validated in surfactant media by using cyclic, differential pulse and square-wave voltammetry. Addition of Tween-20 to the drotaverine hydrochloride containing electrolyte enhances the reduction current signal. The voltammograms of the drug with Tween-20 in phosphate buffers of pH 2.511.0 exhibit a single well defined reduction peak which may be due to the reduction of Cdouble bond; length as m-dashC group. The cyclic voltammetric studies indicated the reduction of drotaverine hydrochloride at the electrode surface through two electron irreversible step and diffusion-controlled. The peak current showed a linear dependence with the drug concentration over the range 0.87.2 μg mL−1. The calculated LOD and LOQ are 1.8 and 6.0 ng mL−1 by SWCAdSV and 8.1 and 27.2 ng mL−1 by DPCAdSV, respectively. The procedure was applied to the assay of the drug in tablet form with mean percentage recoveries of 100.2% with SWCAdSV and 99.7% with DPCAdSV. The validity of the proposed methods was further assessed by applying a standard addition technique. |
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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 |
000285858200010 |
Publication Date |
2010-09-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
0927-7765 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
|
Times cited |
|
Open Access |
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| |
Notes |
|
Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:98686 |
Serial |
8742 |
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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 |
Type |
A1 Journal article |
| |
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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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 |
000264759400025 |
Publication Date |
2009-03-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0003-2700; 5206-882x |
ISBN |
|
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 |
|
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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| Permanent link to this record |
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Author |
Lind, O.C.; Salbu, B.; Janssens, K.; Proost, K.; Dahlgaard, H. |
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Title |
Characterization of uranium and plutonium containing particles originating from the nuclear weapons accident in Thule, Greenland, 1968 |
Type |
A1 Journal article |
| |
Year |
2005 |
Publication |
Journal of environmental radioactivity |
Abbreviated Journal |
J Environ Radioactiv |
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| |
Volume |
81 |
Issue |
|
Pages |
21-32 |
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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 |
000228714500003 |
Publication Date |
2005-03-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0265-931x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.31 |
Times cited |
37 |
Open Access |
|
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| |
Notes |
|
Approved |
Most recent IF: 2.31; 2005 IF: 1.243 |
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| |
Call Number |
UA @ admin @ c:irua:52231 |
Serial |
5507 |
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| Permanent link to this record |
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Author |
Johansson, T.B.; Van Grieken, R.E.; Winchester, J.W. |
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Title |
Elemental abundance variation with particle-size in north florida aerosols |
Type |
A1 Journal article |
| |
Year |
1976 |
Publication |
Journal of geophysical research |
Abbreviated Journal |
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| |
Volume |
81 |
Issue |
6 |
Pages |
1039-1046 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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| |
Abstract |
A nonurban base line has been established for nine trace element constituents of aerosol particles as a function of particle size at ground level sampling stations in north Florida up to 50 km from the Gulf of Mexico. The particle size range 0.25- to >4-μm aerodynamic diameter was investigated by cascade impactor sampling and elemental analysis by proton-induced X ray emission. By using a strategy of sampling at urban, forest, and coastal locations and by choosing approximately 48-hour sample averaging intervals the potential dependence of the base line levels both on local pollution and natural sources and on local particle size specific aerosol removal processes could be evaluated. It is found that elements contained in the largest particles, especially those of >4 μm, display the greatest degree of average concentration difference between sites, a result suggesting short atmospheric residence times and the importance of local dispersion sources and atmospheric cleansing processes in regulating the particle concentrations in air. Elements contained in particles of <2-μm diameter show little average concentration difference between sites unless they are influenced by local pollution sources, a finding suggesting that their concentrations in air are regulated by large-scale sources and transport processes. Sulfur in the smallest particles shows a marked constancy of concentration, but it may be modified in the largest particle size ranges in relation to proximity to the seacoast. No evidence is found for dependence of particulate sulfur concentrations on local pollution sources. K, Ca, Ti, Fe, and Zn appear to be regulated in the main by terrestrial source processes, and Cl by marine source processes, but Br and Pb appear to be accounted for adequately by assuming automotive fuel combustion as their major source. Limited data obtained for V indicate that it may vary considerably with fluctuations in aerosol transport from oil-fired electric power plant sources in the region. Limited additional data also suggest that Mn is derived from sources of natural terrestrial composition. In view of these findings, certain criteria may be set for the design of a meaningful nonurban aerosol monitoring network. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
A1976BG78300001 |
Publication Date |
2008-02-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0148-0227; 2156-2202; 0022-1406; 0196-6928; 0196-6936; 0885-3401; 8755-8556; 0196-2256; 0747-7309; 1 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
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Times cited |
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Open Access |
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| |
Notes |
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Approved |
no |
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| |
Call Number |
UA @ admin @ c:irua:113637 |
Serial |
7879 |
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| Permanent link to this record |
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Author |
Marguí, E.; van Meel, K.; Van Grieken, R.; Buendía, A.; Fontás, C.; Hidalgo, M.; Queralt, I. |
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| |
Title |
Method for the determination of Pd-catalyst residues in active pharmaceutical ingredients by means of high-energy polarized-beam energy dispersive X-ray fluorescence |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
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| |
Volume |
81 |
Issue |
4 |
Pages |
1404-1410 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
In medicinal chemistry, Pd is perhaps the most-widely utilized precious metal, as catalyst in reactions which represent key transformations toward the synthesis of new active pharmaceutical ingredients (APIs). The disadvantage of this metal-catalyzed chemistry is that expensive and toxic metal residues are invariably left bound to the desired product. Thus, stringent regulatory guidelines exist for the amount of residual Pd that a drug candidate is allowed to contain. In this work, a rapid and simple method for the determination of Pd in API samples by high-energy polarized-beam energy dispersive X-ray fluorescence spectrometry has been developed and validated according to the specification limits of current legislation (10 mg kg−1 Pd) and the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH guidelines). Sample and calibration standards preparation includes a first step of homogenization and then, in a second step, the pressing of the powdered material into pellets without any chemical treatment. The use of several synthetic calibration standards made of cellulose to simulate the API matrix appears to be an effective means to obtain reliable calibration curves with a good spread of data points over the working range. With the use of the best measuring conditions, the limit of detection (0.11 mg kg−1 Pd) as well as the limit of quantitation (0.37 mg kg−1 Pd) achieved meet rigorous requirements. The repeatability of the XRF measurement appeared to be less than 2%, while the precision of the whole method was around 7%. Trueness was evaluated by analyzing spiked API samples at the level of the specification limit and calculating the recovery factor, which was better than 95%. To study the applicability of the developed methodology for the intended purpose, three batches of the studied API were analyzed for their Pd content, and the attained results were comparable to those obtained by the daily routine method (acid digestion plus atomic spectroscopy) used in most pharmaceutical laboratories. |
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Wos |
000263319000015 |
Publication Date |
2009-01-22 |
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0003-2700; 5206-882x |
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UA library record; WoS full record; WoS citing articles |
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Call Number |
UA @ admin @ c:irua:74340 |
Serial |
8220 |
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Author |
Dik, J.; Janssens, K.; van der Snickt, G.; van der Loeff, L.; Rickers, K.; Cotte, M. |
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Title |
Visualization of a lost painting by Vincent van Gogh using synchrotron radiation based X-ray fluorescence elemental mapping |
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A1 Journal article |
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Year |
2008 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
80 |
Issue |
16 |
Pages |
6436-6442 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Vincent van Gogh (1853−1890), one of the founding fathers of modern painting, is best known for his vivid colors, his vibrant painting style, and his short but highly productive career. His productivity is even higher than generally realized, as many of his known paintings cover a previous composition. This is thought to be the case in one-third of his early period paintings. Van Gogh would often reuse the canvas of an abandoned painting and paint a new or modified composition on top. These hidden paintings offer a unique and intimate insight into the genesis of his works. Yet, current museum-based imaging tools are unable to properly visualize many of these hidden images. We present the first-time use of synchrotron radiation based X-ray fluorescence mapping, applied to visualize a womans head hidden under the work Patch of Grass by Van Gogh. We recorded decimeter-scale, X-ray fluorescence intensity maps, reflecting the distribution of specific elements in the paint layers. In doing so we succeeded in visualizing the hidden face with unprecedented detail. In particular, the distribution of Hg and Sb in the red and light tones, respectively, enabled an approximate color reconstruction of the flesh tones. This reconstruction proved to be the missing link for the comparison of the hidden face with Van Goghs known paintings. Our approach literally opens up new vistas in the nondestructive study of hidden paint layers, which applies to the oeuvre of Van Gogh in particular and to old master paintings in general. |
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000258448100039 |
Publication Date |
2008-07-29 |
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ISSN |
0003-2700; 5206-882x |
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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 |
178 |
Open Access |
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Most recent IF: 6.32; 2008 IF: 5.712 |
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Call Number |
UA @ admin @ c:irua:74466 |
Serial |
5906 |
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