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Author Smits, J.; Van Grieken, R. pdf  doi
openurl 
  Title Enrichment of trace anions from water with 2,2'-diaminodiethylamine cellulose filters Type A1 Journal article
  Year 1981 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 123 Issue Pages 9-17  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Cellulose filters with immobilized 2,2'-diaminodiethylamine (DEN) functional groups are studied for trace anion preconcentration from aqueous solution, with subsequent x-ray fluorescence measurements. For most oxoanions with a central metal atom, nearly quantitative collection can be achieved by 10-cm2 DEN filters under the following optimized conditions: pH 36, filtration rate up to 0.5 ml cm-2 min-1, and sample volume up to 100 ml cm-2. The collection yield is independent of the trace oxoanion concentration up to at least 1.5 μmol cm-2. Although the DEN filter exhibits some selectivity towards oxoanions with a central metal atom, ionic strength affects the results; the collection efficiency is strongly depressed with salt (e.g. NaCl) concentrations above 0.01 M. The applicability of the DEN filter in anion collection is therefore limited to dilute solutions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1981LA22400002 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116437 Serial 7922  
Permanent link to this record
 

 
Author Robberecht, H.; Van Grieken, R.; Shani, J.; Barak, S. pdf  doi
openurl 
  Title Evaluation of multi-element analysis of blood serum by energy-dispersive x-ray spectrometry Type A1 Journal article
  Year 1982 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 136 Issue Pages 285-292  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Conventional energy-dispersive x-ray fluorescence is applied in the analysis of blood serum to give the concentrations of 710 elements simultaneously with minimal manipulation of the samples. Simple spotting onto a Mylar carrier of 250 μl of serum, doped with two internal standards, was chosen as the sample preparation step. Some 200 serum samples, analyzed in replicate (n = 26), were used to evaluate this procedure. The detection limits are 4 μg ml-1 for K and Ca, 0.50.2 μg ml-1 for Fe, Cu, Pb and Zn, and less than 0.1 μg ml-1 for Se, Rb and Sr. Well above these limits, the standard deviation is around 10%. Comparison with the results of other measurements on the same samples indicates an accuracy of that order. The simplicity and high throughput, and the possibility of automating the x.r.f. measurements, make the proposed procedure suitable for screening large numbers of sera.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1982NL48600032 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116440 Serial 7940  
Permanent link to this record
 

 
Author Verbueken, A.H.; Van Grieken, R.E.; de Broe, M.E.; Wedeen, R.P. pdf  doi
openurl 
  Title Identification of inorganic and organic microliths in kidney sections by laser microprobe mass spectrometry Type A1 Journal article
  Year 1987 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 195 Issue Pages 97-115  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract Laser microprobe mass spectrometry is used to identify intrarenal microliths; they appear to consist of either oxalate, urate or phosphate. Crystalline and amorphous deposits in rat and human kidney are pin-pointed by the laser beam and their chemical composition determined by mass spectrometry. The method has the potential for wide application in the identification of single organic, inorganic or combination crystals in histological sections.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1987K019500009 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116448 Serial 8055  
Permanent link to this record
 

 
Author Vos, L.; Robberecht, H.; Van Dyck, P.; Van Grieken, R. pdf  doi
openurl 
  Title Multi-element analysis of urine by energy-dispersive x-ray fluorescence spectrometry Type A1 Journal article
  Year 1981 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 130 Issue 1 Pages 167-175  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract For multi-element analysis of human urine, 25-ml samples doped with yttrium as internal standard are evaporated gently and then ashed up to 460°C overnight. The residue is pelletized and analysed by energy-dispersive x-ray fluorescence. Acid addition to facilitate the digestion is not mandatory. Recoveries are nearly quantitative for traces of Fe, Ni, Cu, Zn and Sr, to a lesser extent for lead, but not for arsenic or selenium. The standard deviation per measurement is typically around 6%. The detection limits are such that some 10 elements can be determined simultaneously in normal urine, and possibly more in cases of importance to toxicology or industrial hygiene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1981ME98900017 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116439 Serial 8285  
Permanent link to this record
 

 
Author Van Grieken, R.; Speecke, A.; Hoste, J. pdf  doi
openurl 
  Title On the precision of oxygen determinations in steel by 14-MeVv neutron activation Type A1 Journal article
  Year 1970 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 52 Issue 2 Pages 275-280  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The precision of the 14-MeV neutron activation determination of oxygen in steel has been examined as a function of the oxygen content for a large number of steel and cast iron samples. The experimental and the statistically expected standard deviations have been compared. In the conditions used, 2.5 counts from 16N were registered for each p.p.m. of oxygen in the samples. The neutron flux was monitored by a simultaneously irradiated oxygen standard.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116362 Serial 8332  
Permanent link to this record
 

 
Author Smits, J.; Van Grieken, R. pdf  doi
openurl 
  Title Optimization of a simple spotting procedure for x-ray fluorescence analysis of waters Type A1 Journal article
  Year 1977 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 88 Issue 1 Pages 97-107  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Several sample preparation methods for waters for energy-dispersive x.r.f. were examined, as well as the influence of sample size on the analytical characteristics. The most satisfactory simple, rapid method proved to be spotting of 1.5 ml of water sample on a Whatman-41 cellulose filter paper provided with a wax ring of 29-mm diameter and evaporating the water with an unheated air stream from underneath. Sensitivities are below 100 p.p.b. for most elements and often below 50 p.p.b. when the optimal secondary fluorescer is used. Accuracy and precision are usually in the 1520 % range. The method is applicable to many dilute aqueous solutions as is illustrated by analysis of industrial water samples and ashed biological material.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1977CQ82600011 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116367 Serial 8337  
Permanent link to this record
 

 
Author Van Grieken, R. pdf  doi
openurl 
  Title Preconcentration methods for the analysis of water by X-ray spectrometric techniques Type A1 Journal article
  Year 1982 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 143 Issue Pages 3-34  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract All published procedures for multi-element preconcentration of trace elements, prior to x-ray fluorescence analysis of water, are reviewed and critically evaluated. Most preconcentration methods applied to the determination of single elements in water are also listed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1982PT27300002 Publication Date 2002-10-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116441 Serial 8401  
Permanent link to this record
 

 
Author Vos, L.; Van Grieken, R. pdf  doi
openurl 
  Title Preparation of conducting electrodes from biological samples for multi-element trace analysis by spark-source mass spectrometry or emission spectrometry Type A1 Journal article
  Year 1984 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 164 Issue Pages 83-90  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Four decomposition procedures frequently used for biological material (dry ashing, open wet digestion, wet digestion in a teflon bomb and low-temperature ashing) are optimized for the conversion of biological samples to conducting electrodes suitable for multi-element trace determinations by spark-source mass spectrometry or emission spectrometry. The optimized procedures are evaluated with respect to contamination, retention and preconcentration of the trace elements, homogeneity of the electrodes and precision of the final results. Both dry-ashing methods are prone to losses by volatilization; simple dry ashing suffers from contamination problems during electrode preparation. Wet digestion gives better precision; digestion with nitric/sulfuric acids in an open flask is the method of choice for most elements being simpler and giving lower blanks than the bomb method.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1984ABC2700007 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116443 Serial 8411  
Permanent link to this record
 

 
Author Lins Galdino, S.M.; Costa Dantas, C.; Van Grieken, R. pdf  doi
openurl 
  Title Radio-isotope neutron activation analysis for vanadium, manganese and tungsten in alloy steels Type A1 Journal article
  Year 1987 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 196 Issue Pages 337-343  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract An instrumental neutron activation method for V, Mn and W in alloy steels with a 241 Am/Be isotopic neutron source is described. The samples were irradiated to induce the nuclear reactions 51V(n, γ) 52V, 55Mn(n, γ)56Mn, and 186W(n, γ)187W. The activities were measured with a NaI(TI) detector. Interferences on the measured photopeaks were shown to be negligible by measuring the half-lives of 62V, 56Mn and 187W.These thre elementes were determined in the range 1.512.9% in special steels; manganese in the range 0.51.6% was measured in cast irons. Calibration was done by comparison with results from wet chemistry and x-ray fluorescence spectrometry. The processing times for the vanadium, manganese and tungsten determinations were 11 min, 3 h and 26.3 h, respectively, but these were reduced greatly by intoruding a scheme wherein six samples were simultaneously irradiated and the 56Mn and 187W nuclides were measured sequentially for a series of 66 samples. The average processing time was reduced to 45 min for tungsten with a precision of 4.0% and accuracy of 3.4% and 22.8 min for manganese with a precision of 3.8% and accuracy of 3.1%.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1987K058900044 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116445 Serial 8449  
Permanent link to this record
 

 
Author Vanderborght, B.; Van Grieken, R. pdf  doi
openurl 
  Title Reduction of trace metal levels in analytical-grade activated carbon Type A1 Journal article
  Year 1977 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 89 Issue 2 Pages 399-402  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1977DB52500022 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116368 Serial 8466  
Permanent link to this record
 

 
Author Van Grieken, R.; Van de Velde, R.; Robberecht, H. pdf  doi
openurl 
  Title Sample contamination from a commercial grinding unit Type A1 Journal article
  Year 1980 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 118 Issue 1 Pages 137-143  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The contamination of ground samples by a commercially available Lovibond McCrone Micronizing Mill is discussed. Tracer and weighing experiments showed that abrasion of corundum grinding elements was important, introducing 620 mg of abrasion products per minute of wet grinding. Agate grinding elements were abraded at ⩽6 mg min-1. The abrasion products and grinding elements were analyzed by x-ray fluorescence, spark-source mass spectrometry and neutron activation analysis. Contamination in trace element analysis of geological materials is likely to be negligible for agate grinding elements and, except for a few transition metals, also for corundum grinding elements. Contamination of typical biological samples is significant for a few elements even when agate elements are used, and is absolutely prohibitive for trace analysis when corundum elements are used.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1980JZ95100016 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116436 Serial 8492  
Permanent link to this record
 

 
Author Vandecasteele, C.; Van Grieken, R.; Hoste, J. pdf  doi
openurl 
  Title Simultaneous determination of chromium and silicon in steel by 14-mev neutron activation analysis Type A1 Journal article
  Year 1974 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 72 Issue 1 Pages 31-36  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Chromium and silicon are determined simultaneously in steel by 14-MeV neutron activation analysis. The activities of 52V(Eγ=1.43 MeV,TView the MathML source=3.76 min) from 52Cr(n,p)52V and 28Al (Eγ=1.78 MeV; TView the MathML source=2.24 min) from 28Si(n,p)28Al are evaluated by mixed γ-ray spectrometry. The influence of manganese and phosphorus, the main interfering elements, is negligible for most stainless steels. The count rate should be limited, to avoid 52V pulse pile-up effects interfering in the 28Al energy region. Precisions in the 2-10% range are reached, depending on the concentrations, for a 10-min analysis time. Results for a series of steel samples are compared with industrial analyses.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1974U036600002 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116366 Serial 8527  
Permanent link to this record
 

 
Author Van Grieken, R.; Van 't dack, L.; Costa Dantas, C.; Da Silveira Dantas, H. pdf  doi
openurl 
  Title Soil analysis by thin-film energy-dispersive X-ray fluorescence Type A1 Journal article
  Year 1979 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 108 Issue Pages 93-101  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Energy-dispersive x-ray fluorescence is advantageous for trace analysis of soils present as thin films. A target thickness of about 2 mg cm-2 provides a compromise between optimal sensitivity and minimal absorption effect or optimal accuracy. Sample preparation involves only suspending the finely ground soil in water and drying this suspension on a thin mylar foil glued on a ring that fits into the x.r.f. spectrometer. The effective sample weight present in the exciting beam area is computed from the scatter peaks, a method that cancels out target heterogeneity problems. High accuracy is demonstrated for many elements in reference soil and rock materials; a precision around 5% and a detection limit around 10 ppm can be achieved. As an illustration, results for 16 trace elements and preliminary interpretation are given for a series of pedologically important soil samples from Brasil.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1979HL44100012 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:111402 Serial 8549  
Permanent link to this record
 

 
Author Otten, P.; Bruynseels, F.; Van Grieken, R. pdf  doi
openurl 
  Title Study of inorganic ammonium compounds in individual marine aerosol particles by laser microprobe mass spectrometry Type A1 Journal article
  Year 1987 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 195 Issue Pages 117-124  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Ammonia is important in the atmosphere because it neutralizes acidic species. The relative importance of different inorganic ammonium compounds (chloride, nitrate and sulfate) in marine air chemistry was studied by single-particle characterization with the laser microprobe mass analyser. Standard aerosols were generated as a reference for compound identification, based on the fingerprint spectra obtained, and calculation of the relative sensitivity achieved for different ions in a marine aerosol matrix. The relative sensitivity for ammonium was low. Aerosol samples were collected in the Southern Bight of the North Sea under different meteorological conditions and examined for their ammonium compounds. Samples collected during an inversion period with continental influences showed a much higher content in all particles than samples collected under different meteorological conditions, where ammonium was mostly detected in the submicrometer particle-size range.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1987K019500010 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116447 Serial 8601  
Permanent link to this record
 

 
Author Leysen, L.; Roekens, E.; Komy, Z.; Van Grieken, R. pdf  doi
openurl 
  Title A study of the weathering of an historic building Type A1 Journal article
  Year 1987 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 195 Issue Pages 247-255  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Various bulk and surface analytical techniques were used to study the chemical deterioration of the 13th-to-15th century limestone cathedral in Mechelen, Belgium. The weathering crust on the walls was found to be rich in sulfate, regardless of the geographic orientation. Nitrate and chloride were only detected in minor amounts in the crust and run-off samples. Attack by gaseous sulfur compounds seems to play a dominant role in the stone deterioration mechanism. Electron microprobe analysis showed predominantly bar-shaped gypsum crystals in the crust, and laser microprobe mass spectrometry showed that carbon seems to be responsible for the blackness of most crust samples. Automated electron microprobe analysis also indicated significant differences in the analytical composition of suspensions in run-off water and in rain-water.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1987K019500022 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:116446 Serial 8608  
Permanent link to this record
 

 
Author Treiger, B.; van Malderen, H.; Bondarenko, I.; van Espen, P.; Van Grieken, R. doi  openurl
  Title Studying aerosol samples by non-linear mapping of electron probe microanalysis data Type A1 Journal article
  Year 1993 Publication (up) Analytica chimica acta Abbreviated Journal  
  Volume 284 Issue Pages 119-124  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos A1993MR27600014 Publication Date 2002-07-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2670; 1873-4324 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:6224 Serial 8610  
Permanent link to this record
 

 
Author Jaroszewicz, J.; de Nolf, W.; Janssens, K.; Michalski, A.; Falkenberg, G. doi  openurl
  Title Advantages of combined mu-XRF and mu-XRD for phase characterization of Ti-B-C ceramics compared with conventional X-ray diffraction Type A1 Journal article
  Year 2008 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 391 Issue 4 Pages 1129-1133  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000256088700005 Publication Date 2008-05-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.431 Times cited 7 Open Access  
  Notes Approved Most recent IF: 3.431; 2008 IF: 3.328  
  Call Number UA @ admin @ c:irua:69317 Serial 5459  
Permanent link to this record
 

 
Author Cagno, S.; Janssens, K.; Mendera, M. doi  openurl
  Title Compositional analysis of Tuscan glass samples: in search of raw materials fingerprints Type A1 Journal article
  Year 2008 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 391 Issue 4 Pages 1389-1395  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000256088700035 Publication Date 2008-02-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.431 Times cited 26 Open Access  
  Notes Approved Most recent IF: 3.431; 2008 IF: 3.328  
  Call Number UA @ admin @ c:irua:69320 Serial 5545  
Permanent link to this record
 

 
Author Janssens, K.; van Espen, P.; Van 't dack, L. doi  openurl
  Title Euroanalysis 14: the European Conference on Analytical Chemistry Type Editorial
  Year 2008 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 391 Issue 4 Pages 1107-1108  
  Keywords Editorial; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000256088700001 Publication Date 2008-05-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 3.431 Times cited Open Access  
  Notes Approved Most recent IF: 3.431; 2008 IF: 3.328  
  Call Number UA @ admin @ c:irua:69316 Serial 5608  
Permanent link to this record
 

 
Author Bugani, S.; Camaiti, M.; Morselli, L.; Van de Casteele, E.; Janssens, K. doi  openurl
  Title Investigating morphological changes in treated vs. untreated stone building materials by x-ray micro-CT Type A1 Journal article
  Year 2008 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 391 Issue 4 Pages 1343-1350  
  Keywords A1 Journal article; Vision lab; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000256088700030 Publication Date 2008-03-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.431 Times cited 25 Open Access  
  Notes Approved Most recent IF: 3.431; 2008 IF: 3.328  
  Call Number UA @ admin @ c:irua:69319 Serial 5673  
Permanent link to this record
 

 
Author Terzano, R.; Alfeld, M.; Janssens, K.; Vekemans, B.; Schoonjans, T.; Vincze, L.; Tomasi, N.; Pinton, R.; Cesco, S. pdf  doi
openurl 
  Title Spatially resolved (semi)quantitative determination of iron (Fe) in plants by means of synchrotron micro X-ray fluorescence Type A1 Journal article
  Year 2013 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 405 Issue 10 Pages 3341-3350  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Iron (Fe) is an essential element for plant growth and development; hence determining Fe distribution and concentration inside plant organs at the microscopic level is of great relevance to better understand its metabolism and bioavailability through the food chain. Among the available microanalytical techniques, synchrotron mu-XRF methods can provide a powerful and versatile array of analytical tools to study Fe distribution within plant samples. In the last years, the implementation of new algorithms and detection technologies has opened the way to more accurate (semi)quantitative analyses of complex matrices like plant materials. In this paper, for the first time the distribution of Fe within tomato roots has been imaged and quantified by means of confocal mu-XRF and exploiting a recently developed fundamental parameter-based algorithm. With this approach, Fe concentrations ranging from few hundreds of ppb to several hundreds of ppm can be determined at the microscopic level without cutting sections. Furthermore, Fe (semi)quantitative distribution maps were obtained for the first time by using two opposing detectors to collect simultaneously the XRF radiation emerging from both sides of an intact cucumber leaf.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000316338700033 Publication Date 2013-02-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.431 Times cited 27 Open Access  
  Notes ; Research was supported by grants from Italian MIUR (FIRB-Programma “Futuro in Ricerca”) and Free University of Bolzano (TN5046 and TN5056). Synchrotron experiments at HASY-LAB were financially supported by the European Community Research Infrastructure Action under the FP6 “Structuring the European Research Area” Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). Matthias Alfeld receives a Ph.D. fellowship of the Research Foundation-Flanders (FWO). We thank Karen Rickers-Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; Approved Most recent IF: 3.431; 2013 IF: 3.578  
  Call Number UA @ admin @ c:irua:108261 Serial 5838  
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Author Bugani, S.; Modugno, F.; Lucejko, J.J.; Giachi, G.; Cagno, S.; Cloetens, P.; Janssens, K.; Morselli, L. pdf  doi
openurl 
  Title Study on the impregnation of archaeological waterlogged wood with consolidation treatments using synchrotron radiation microtomography Type A1 Journal article
  Year 2009 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 395 Issue 7 Pages 1977-1985  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract In favourable conditions of low temperature and low oxygen concentration, archaeological waterlogged wooden artefacts, such as shipwrecks, can survive with a good state of preservation. Nevertheless, anaerobic bacteria can considerably degrade waterlogged wooden objects with a significant loss in polysaccharidic components. Due to these decay processes, wood porosity and water content increase under ageing. In such conditions, the conservation treatments of archaeological wooden artefacts often involve the replacement of water with substances which fill the cavities and help to prevent collapse and stress during drying. The treatments are very often expensive and technically difficult, and their effectiveness very much depends on the chemical and physical characteristics of the substances used for impregnation. Also important are the degree of cavity-filling, penetration depth and distribution in the structure of the wood. In this study, the distribution in wood cavities of some mixtures based on polyethylene glycols and colophony, used for the conservation of waterlogged archaeological wood, was investigated using synchrotron radiation X-ray computed microtomography (SR-A mu CT). This non-destructive imaging technique was useful for the study of the degraded waterlogged wood and enabled us to visualise the morphology of the wood and the distribution of the materials used in the wood treatments. The study has shown how deposition is strictly related to the dimension of the wooden cavities. The work is currently proceeding with the comparison of synchrotron observations with the data of the solutions viscosity and with those of the properties imparted to the wood by the treatments.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000272017000005 Publication Date 2009-09-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.431 Times cited 30 Open Access  
  Notes Approved Most recent IF: 3.431; 2009 IF: 3.480  
  Call Number UA @ admin @ c:irua:94493 Serial 5853  
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Author Moro, G.; Barich, H.; Driesen, K.; Montiel, N.F.; Neven, L.; Mendonca, C.D.; Thiruvottriyur Shanmugam, S.; Daems, E.; De Wael, K. pdf  doi
openurl 
  Title Unlocking the full power of electrochemical fingerprinting for on-site sensing applications Type A1 Journal article
  Year 2020 Publication (up) Analytical And Bioanalytical Chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume Issue Pages 1-14  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Electrochemical sensing for the semi-quantitative detection of biomarkers, drugs, environmental contaminants, food additives, etc. shows promising results in point-of-care diagnostics and on-site monitoring. More specifically, electrochemical fingerprint (EF)-based sensing strategies are considered an inviting approach for the on-site detection of low molecular weight molecules. The fast growth of electrochemical sensors requires defining the concept of direct electrochemical fingerprinting in sensing. The EF can be defined as the unique electrochemical signal or pattern, mostly recorded by voltammetric techniques, specific for a certain molecule that can be used for its quantitative or semi-quantitative identification in a given analytical context with specified circumstances. The performance of EF-based sensors can be enhanced by considering multiple features of the signal (i.e., oxidation or reduction patterns), in combination with statistical data analysis or sample pretreatments or by including electrode surface modifiers to enrich the EF. In this manuscript, some examples of EF-based sensors, strategies to improve their performances, and open challenges are discussed to unlock the full power of electrochemical fingerprinting for on-site sensing applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000523396300002 Publication Date 2020-04-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.3 Times cited 3 Open Access  
  Notes ; The presented review is the result of a concerted effort and fruitful discussions among enthusiastic, young, and (for the occasion) female researchers of the AXES research group, each of them with specific expertise and background, under the guidance of the corresponding author. The authors acknowledge FWO-Flanders, BOF-UA, IOF-UA, FAPESP and EU for funding. ; Approved Most recent IF: 4.3; 2020 IF: 3.431  
  Call Number UA @ admin @ c:irua:168563 Serial 6647  
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Author Swaenen, M.; Stefaniak, E.A.; Frost, R.; Worobiec, A.; Van Grieken, R. doi  openurl
  Title Investigation of inclusions trapped inside Libyan desert glass by Raman microscopy Type A1 Journal article
  Year 2010 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal  
  Volume 397 Issue 7 Pages 2659-2665  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract Several specimens of Libyan desert glass (LDG), an enigmatic natural glass from Egypt, were subjected to investigation by micro-Raman spectroscopy. The spectra of inclusions inside the LDG samples were successfully measured through the layers of glass and the mineral species were identified on this basis. The presence of cristobalite as typical for high-temperature melt products was confirmed, together with co-existing quartz. TiO2 was determined in two polymorphic species rutile and anatase. Micro-Raman spectroscopy proved also the presence of minerals unusual for high-temperature glasses such as anhydrite and aragonite.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000280122100004 Publication Date 2010-01-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642; 1618-2650 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:83276 Serial 8125  
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Author Avigo, D.; Godoi, A.F.L.; Janissek, P.R.; Makarovska, Y.; Krata, A.; Potgieter-Vermaak, S.; Alfoldy, B.; Van Grieken, R.; Godoi, R.H.M. doi  openurl
  Title Particulate matter analysis at elementary schools in Curitiba, Brazil Type A1 Journal article
  Year 2008 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal  
  Volume 391 Issue 4 Pages 1459-1468  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000256088700043 Publication Date 2008-03-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642; 1618-2650 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:68797 Serial 8360  
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Author Cabal Rodríguez, A.E.; Leyva Pernia, D.; Schalm, O.; van Espen, P.J.M. pdf  doi
openurl 
  Title Possibilities of energy-resolved X-ray radiography for the investigation of paintings Type A1 Journal article
  Year 2012 Publication (up) Analytical and bioanalytical chemistry Abbreviated Journal  
  Volume 402 Issue 4 Pages 1471-1480  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract X-ray radiographic images of paintings often show little or no contrast. In order to increase the contrast in radiographic images we measured the X-ray spectrum of a low power X-ray tube, after passing through the painting, with a high energy-resolution SDD detector. To obtain images, the detector is collimated with a 400 mu m diameter pinhole and the painting was moved through the beam in the x and y-direction using a dwell time of a few seconds per pixel. The data obtained consists of a data cube of, typically, 200 x 200 pixels and a 512-channel X-ray spectrum for each pixel, spanning the energy range from 0 to 40 keV. Having the absorbance spectrum available for each pixel, we are able, a posteriori, to produce images by edge subtraction for any given element. In this way high contrast, element-specific, images can be obtained. Because of the high energy-resolution a much simpler edge subtraction algorithm can be applied. We also used principal-component imaging to obtain, in a more automated way, images with high contrast. Some of these images can easily be attributed to specific elements. It turns out that preprocessing of the spectral data is crucial for the success of the multivariate image processing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000299842000008 Publication Date 2011-07-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642; 1618-2650 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:96200 Serial 8394  
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Author Dillen, A.; Vandezande, W.; Daems, D.; Lammertyn, J. pdf  doi
openurl 
  Title Unraveling the effect of the aptamer complementary element on the performance of duplexed aptamers : a thermodynamic study Type A1 Journal article
  Year 2021 Publication (up) Analytical And Bioanalytical Chemistry Abbreviated Journal Anal Bioanal Chem  
  Volume 413 Issue 19 Pages 4739-4750  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Duplexed aptamers (DAs) are widespread aptasensor formats that simultaneously recognize and signal the concentration of target molecules. They are composed of an aptamer and aptamer complementary element (ACE) which consists of a short oligonucleotide that partially inhibits the aptamer sequence. Although the design principles to engineer DAs are straightforward, the tailored development of DAs for a particular target is currently based on trial and error due to limited knowledge of how the ACE sequence affects the final performance of DA biosensors. Therefore, we have established a thermodynamic model describing the influence of the ACE on the performance of DAs applied in equilibrium assays and demonstrated that this relationship can be described by the binding strength between the aptamer and ACE. To validate our theoretical findings, the model was applied to the 29-mer anti-thrombin aptamer as a case study, and an experimental relation between the aptamer-ACE binding strength and performance of DAs was established. The obtained results indicated that our proposed model could accurately describe the effect of the ACE sequence on the performance of the established DAs for thrombin detection, applied for equilibrium assays. Furthermore, to characterize the binding strength between the aptamer and ACEs evaluated in this work, a set of fitting equations was derived which enables thermodynamic characterization of DNA-based interactions through thermal denaturation experiments, thereby overcoming the limitations of current predictive software and chemical denaturation experiments. Altogether, this work encourages the development, characterization, and use of DAs in the field of biosensing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000659366300001 Publication Date 2021-06-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1618-2642; 1618-2650 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.431 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 3.431  
  Call Number UA @ admin @ c:irua:179163 Serial 8713  
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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.; pdf  doi
openurl 
  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
  Year 2013 Publication (up) Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 85 Issue 2 Pages 860-867  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  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).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000313668400031 Publication Date 2012-10-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 79 Open Access  
  Notes Goa; Fwo Approved Most recent IF: 6.32; 2013 IF: 5.825  
  Call Number UA @ lucian @ c:irua:108707UA @ admin @ c:irua:108707 Serial 631  
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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. pdf  doi
openurl 
  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
  Year 2011 Publication (up) Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 83 Issue 4 Pages 1214-1223  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  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.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000287176900011 Publication Date 2011-02-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2700;1520-6882; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 113 Open Access  
  Notes Iuap; Fwo Approved Most recent IF: 6.32; 2011 IF: 5.856  
  Call Number UA @ lucian @ c:irua:88794UA @ admin @ c:irua:88794 Serial 632  
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Author Rahemi, V.; Sarmadian, N.; Anaf, W.; Janssens, K.; Lamoen, D.; Partoens, B.; De Wael, K. pdf  url
doi  openurl
  Title Unique opto-electronic structure and photo reduction properties of sulfur doped lead chromates explaining their instability in paintings Type A1 Journal article
  Year 2017 Publication (up) Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 89 Issue 89 Pages 3326-3334  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Chrome yellow refers to a group of synthetic inorganic pigments that became popular as an artists material from the second quarter of the 19th century. The color of the pigment, in which the chromate ion acts as a chromophore, is related to its chemical composition (PbCr1-xSxO4, with 0≤x≤0.8) and crystalline structure (monoclinic/orthorhombic). Their shades range from the yellow-orange to the paler yellow tones with increasing sulfate amount. These pigments show remarkable signs of degradation after limited time periods. Pure PbCrO4 (crocoite in its natural form) has a deep yellow color and is relatively stable, while the co-precipitate with lead sulfate (PbCr1-xSxO4) has a paler shade and seems to degrade faster. This degradation is assumed to be related to the reduction of Cr(VI) to Cr(III). We show that on increasing the sulfur(S)-content in chrome yellow, the band gap increases. Typically, when increasing the band gap, one might assume that a decrease in photo activity is the result. However, the photo activity relative to the Cr content, and thus Cr reduction, of sulfur-rich PbCr1-xSxO4 is found to be much higher compared to the sulfur-poor or non-doped lead chromates. This discrepancy can be explained by the evolution of the crystal and electronic structure as function of the sulfur content: first-principles density functional theory calculations show that both the absorption coefficient and reflection coefficients of the lead chromates change as a result of the sulfate doping in such a way that the generation of electron-hole pairs under illumination relative to the total Cr content increases. These changes in the material properties explain why paler shade yellow colors of this pigment are more prone to discoloration. The electronic structure calculations also demonstrate that lead chromate and its co-precipitates are p-type semiconductors, which explains the observed reduction reaction. As understanding this phenomenon is valuable in the field of cultural heritage, this study is the first joint action of photo-electrochemical measurements and first-principles calculations to approve the higher tendency of sulfur-rich lead chromates to darken.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000397478300015 Publication Date 2017-02-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-2700 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 7 Open Access OpenAccess  
  Notes ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government, department EWI. The BOF-GOA action SOLARPAINT of the University of Antwerp Research Council is acknowledged for financial support. W.A. acknowledges support from BELSPO project S2-ART. Dr. L. Monico and Dr. C. Miliani (ISTM, Perugia) are gratefully acknowledged for helpful discussions and for providing some of the initial batches of the materials studied. ; Approved Most recent IF: 6.32  
  Call Number UA @ lucian @ c:irua:140886 Serial 4451  
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