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Records |
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Author |
Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K. |
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Title |
Cephalosporin antibiotics : electrochemical fingerprints and core structure reactions investigated by LC-MSMS |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
91 |
Issue |
3 |
Pages |
2035-2041 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
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Abstract |
Electrochemistry and exploiting electrochemical fingerprints is a potent approach to address newly emerging surveillance needs, for instance for antibiotics. However, a comprehensive insight in the electrochemical oxidation behaviour and mechanism is re-quired for this sensing strategy. To address the lack in knowledge of the voltammetric behaviour of the cephalosporins antibiotics, a selection of cephalosporin antibiotics and two main intermediates were subjected to an electrochemical study of their redox behaviour by means of pulsed voltammetric techniques and small-scale electrolysis combined with HPLC-MS/MS analyses. Sur-prisingly, the detected oxidation products did not fit the earlier suggested oxidation of the sulfur group to the corresponding sul-foxide. The influence of different side chains, both at the three and the seven position of the β-lactam core structure on the elec-trochemical fingerprint were investigated. Additional oxidation signals at lower potentials were elucidated and linked to different side chains. These signals were further exploited to allow simultaneous detection of different cephalosporins in one voltammetric sweep. These fundamental insights can become the building blocks for an new on-site screening method. |
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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 |
000458220300055 |
Publication Date |
2019-01-03 |
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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 |
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 |
6 |
Open Access |
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Notes |
; The authors acknowledge financial support from the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; |
Approved |
Most recent IF: 6.32 |
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Call Number |
UA @ admin @ c:irua:156046 |
Serial |
5497 |
Permanent link to this record |
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Author |
Rahemi, V.; Trashin, S.; Hafideddine, Z.; Meynen, V.; Van Doorslaer, S.; De Wael, K. |
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Title |
Enzymatic sensor for phenols based on titanium dioxide generating surface confined ROS after treatment with H2O2 |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
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Volume |
283 |
Issue |
283 |
Pages |
343-348 |
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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 |
Titanium dioxide (TiO2) is a popular material as host matrix for enzymes. We now evidence that TiO2 can accumulate and retain reactive oxygen species after treatment by hydrogen peroxide (H2O2) and support redox cycling of a phenolic analyte between horseradish peroxidase (HRP) and an electrode. The proposed detection scheme is identical to that of second generation biosensors, but the measuring solution requires no dissolved H2O2. This significantly simplifies the analysis and overcomes issues related to H2O2 being present (or generated) in the solution. The modified electrodes showed rapid stabilization of the baseline, a low noise level, fast realization of a steady-state current response, and, in addition, improved sensitivity and limit of detection compared to the conventional approach, i.e. in the presence of H2O2 in the measuring solution. Hydroquinone, 4-aminophenol, and other phenolic compounds were successfully detected at sub-μM concentrations. Particularly, a linear response in the concentration range between 0.025 and 2 μM and LOD of 24 nM was demonstrated for 4-aminophenol. The proposed sensor design goes beyond the traditional concept with three sensors generations offering a new possibility for the development of enzymatic sensors based on peroxidases and the formation of ROS on titania after treatment with H2O2. |
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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 |
000455854000043 |
Publication Date |
2018-12-10 |
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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 |
0925-4005 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.401 |
Times cited |
1 |
Open Access |
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Notes |
; The authors thank the University of Antwerp for GOA funding and the Scientific Research-Flanders (FWO) (grant 12T4219N). V. Rahemi is financially supported through a postdoctoral fellowship of the Research Foundation-Flanders (FWO). ; |
Approved |
Most recent IF: 5.401 |
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Call Number |
UA @ admin @ c:irua:155665 |
Serial |
5605 |
Permanent link to this record |
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Author |
van Walsem, J.; Roegiers, J.; Modde, B.; Lenaerts, S.; Denys, S. |
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Title |
Determination of intrinsic kinetic parameters in photocatalytic multi-tube reactors by combining the NTUm-method with radiation field modelling |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemical engineering journal |
Abbreviated Journal |
Chem Eng J |
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Volume |
354 |
Issue |
354 |
Pages |
1042-1049 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
In this work, we propose an adapted Number of Transfer Units (NTUm)-method as an effective tool to determine the Langmuir-Hinshelwood kinetic parameters for a photocatalytic multi-tube reactor. The Langmuir-Hinshelwood rate constant kLH and the Langmuir adsorption constant KL were determined from several experiments under different UV-irradiance conditions, resulting in irradiance depending values for kLH. In order to determine a unique, intrinsic empirical constant k0, valid for all irradiation conditions, we coupled the adapted NTUm-method with a radiation field model to predict UV-irradiance distribution inside the reactor. The final set of kinetic parameters were derived using a Generalized Reduced Gradient (GRG) nonlinear solving method in Matlab which minimizes the differences between model and experimental reactor outlet concentrations of acetaldehyde for various photocatalytic experiments under varying operating conditions, including inlet concentration, flow rate and UV-irradiance. An excellent agreement of the intrinsic empirical constant k0, derived from the coupled NTUm-radiation field model and an earlier published CFD approach was found, emphasizing its validity and reliability. |
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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 |
000445413900099 |
Publication Date |
2018-08-03 |
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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 |
1385-8947; 1873-3212 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.216 |
Times cited |
2 |
Open Access |
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Notes |
; J.V.W. acknowledges the Agentschap Innoveren & Ondernemen for a PhD fellowship. ; |
Approved |
Most recent IF: 6.216 |
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Call Number |
UA @ admin @ c:irua:154845 |
Serial |
5940 |
Permanent link to this record |
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Author |
Van Winckel, T.; Liu, X.; Vlaeminck, S.E.; Takács, I.; Al-Omari, A.; Sturm, B.; Kjellerup, B.V.; Murthy, S.N.; De Clippeleir, H. |
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Title |
Overcoming floc formation limitations in high-rate activated sludge systems |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Chemosphere |
Abbreviated Journal |
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Volume |
215 |
Issue |
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Pages |
342-352 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
High-rate activated sludge (HRAS) is an essential cornerstone of the pursuit towards energy positive sewage treatment through maximizing capture of organics. The capture efficiency heavily relies on the degree of solid separation achieved in the clarifiers. Limitations in the floc formation process commonly emerge in HRAS systems, with detrimental consequences for the capture of organics. This study pinpointed and overcame floc formation limitations present in full-scale HRAS reactors. Orthokinetic flocculation tests were performed with varying shear, sludge concentration, and coagulant or flocculant addition. These were analyzed with traditional and novel settling parameters and extracellular polymeric substances (EPS) measurements. HRAS was limited by insufficient collision efficiency and occurred because the solids retention time (SRT) was short and colloid loading was high. The limitation was predominantly caused by impaired flocculation rather than coagulation. In addition, the collision efficiency limitation was driven by EPS composition (low protein over polysaccharide ratio) instead of total EPS amount. Collision efficiency limitation was successfully overcome by bio-augmenting sludge from a biological nutrient removal reactor operating at long SRT which did not show any floc formation limitations. However, this action brought up a floc strength limitation. The latter was not correlated with EPS composition, but rather EPS amount and hindered settling parameters, which determined floc morphology. With this, an analysis toolkit was proposed that will enable design engineers and operators to tackle activated solid separation challenges found in HRAS systems and maximize the recovery potential of the process. (C) 2018 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000450383400038 |
Publication Date |
2018-10-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0045-6535; 1879-1298 |
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:153978 |
Serial |
8350 |
Permanent link to this record |
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Author |
Bottari, F.; Blust, R.; De Wael, K. |
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Title |
Bio(inspired) strategies for the electro-sensing of β-lactam antibiotics |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Current opinion in electrochemistry |
Abbreviated Journal |
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Volume |
10 |
Issue |
10 |
Pages |
143-148 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The dire previsions of the WHO on the so-called “post-antibiotic era” and the continuous and global rise of anti-microbial resistance, spurs our research community to find better ways to fight these threats. In light of this severe threat to human health many attempts have been made to develop efficient methods to detect antibiotic residues in different streams. The use of electrochemistry seems an inviting approach for on-site and fast monitoring. In this critical review, recent developments in the field of (bio) electro-sensing of 19-lactam antibiotics will be presented, with a focus on aptamers and molecularly imprinted polymers, the two main promises of a new generation of biosensors, yet to be fulfilled. |
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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 |
000442800000022 |
Publication Date |
2018-05-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2451-9103; 2451-9111 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
15 |
Open Access |
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Notes |
; This work was financially supported by the University of Antwerp (BOF) and the Research Foundation – Flanders (FWO). ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:153744 |
Serial |
5488 |
Permanent link to this record |
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Author |
Monico, L.; Chieli, A.; De Meyer, S.; Cotte, M.; de Nolf, W.; Falkenberg, G.; Janssens, K.; Romani, A.; Miliani, C. |
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Title |
Role of the relative humidity and the Cd/Zn stoichiometry in the photooxidation process of cadmium yellows (CdS/Cd1-xZnxS) in oil paintings |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemistry: a European journal |
Abbreviated Journal |
Chem-Eur J |
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Volume |
24 |
Issue |
45 |
Pages |
11584-11593 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Cadmium yellows (CdYs) refer to a family of cadmium sulfide pigments, which have been widely used by artists since the late 19th century. Despite being considered stable, they are suffering from discoloration in iconic paintings, such as Joy of Life by Matisse, Flowers in a blue vase by Van Gogh, and The Scream by Munch, most likely due to the formation of CdSO4 center dot nH(2)O. The driving factors of the CdYs degradation and how these affect the overall process are still unknown. Here, we study a series of oil mock-up paints made of CdYs of different stoichiometry (CdS/Cd0.76Zn0.24S) and crystalline structure (hexagonal/ cubic) before and after aging at variable relative humidity under exposure to light and in darkness. Synchrotron radiation-based X-ray methods combined with UV-Vis and FTIR spectroscopy show that: 1) Cd0.76Zn0.24S is more susceptible to photooxidation than CdS; both compounds can act as photocatalysts for the oil oxidation. 2) The photooxidation of CdS/Cd0.76Zn0.24S to CdSO4 center dot nH(2)O is triggered by moisture. 3) The nature of alteration products depends on the aging conditions and the Cd/Zn stoichiometry. Based on our findings, we propose a scheme for the mechanism of the photocorrosion process and the photocatalytic activity of CdY pigments in the oil binder. Overall, our results form a reliable basis for understanding the degradation of CdS-based paints in artworks and contribute towards developing better ways of preserving them for future generations. |
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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 |
000441126900012 |
Publication Date |
2018-06-06 |
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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 |
0947-6539 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.317 |
Times cited |
5 |
Open Access |
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Notes |
; The research was financially supported by the European research project IPERION-CH, funded by the European Commission, H2020-INFRAIA-2014-2015 (Grant agreement n. 654028) and by the BOF-GOA Project SOLARPaint (University of Antwerp Research Council). For the beamtime grants received, we thank the ESRF (experiments n. HG64, HG95 and in-house beamtimes) and PETRA III-DESY (experiments: I-20130221 EC, I-20160126 EC). We are also grateful to Dr. Jan Garrevoet for his contribution to set up the P06-beamline at PETRA III-DESY. ; |
Approved |
Most recent IF: 5.317 |
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Call Number |
UA @ admin @ c:irua:153733 |
Serial |
5821 |
Permanent link to this record |
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Author |
Castanheiro, A.; Joos, P.; Wuyts, K.; De Wael, K.; Samson, R. |
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Title |
Leaf-deposited semi-volatile organic compounds (SVOCs) : an exploratory study using GCxGC-TOFMS on leaf washing solutions |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Chemosphere |
Abbreviated Journal |
Chemosphere |
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Volume |
214 |
Issue |
214 |
Pages |
103-110 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Airborne particulate matter (PM) includes semi-volatile organic compounds (SVOCs), which can be deposited on vegetation matrices such as plant leaves. In alternative to air-point measurements or artificial passive substrates, leaf monitoring offers a cost-effective, time-integrating means of assessing local air quality. In this study, leaf washing solutions from ivy (Hedera hibernica) leaves exposed during one-month at different land use classes were explored via comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOFMS). The composition of leaf-deposited SVOCs, corrected for those of unexposed leaves, was compared against routinely monitored pollutants concentrations (PM10, PM2.5, O3, NO2, SO2) measured at co-located air monitoring stations. The first study on leaf-deposited SVOCs retrieved from washing solutions, herein reported, delivered a total of 911 detected compounds. While no significant land use (rural, urban, industrial, traffic, mixed) effects were observed, increasing exposure time (from one to 28 days) resulted in a higher number and diversity of SVOCs, suggesting cumulative time-integration to be more relevant than local source variations between sites. After one day, leaf-deposited SVOCs were mainly due to alcohols, N-containing compounds, carboxylic acids, esters and lactones, while ketones, diketones and hydrocarbons compounds gained relevance after one week, and phenol compounds after one month. As leaf-deposited SVOCs became overall more oxidized throughout exposure time, SVOCs transformation or degradation at the leaf surface is suggested to be an important phenomenon. This study confirmed the applicability of GCxGC-TOFMS to analyze SVOCs from leaf washing solutions, further research should include validation of the methodology and comparison with atmospheric organic pollutants. |
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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 |
000449891300013 |
Publication Date |
2018-09-13 |
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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 |
0045-6535; 1879-1298 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.208 |
Times cited |
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Open Access |
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Notes |
; The authors thank the Flemish Environment Agency (VMM) for their collaboration and air quality data; Sam Dekkers and Jonathan Van Waeyenbergh for their help with sample collection. The study was performed using a study set-up funded by the Special Research Fund of the University of Antwerp (KPBOF 2014, no. FFB 140090 'Tree leaf surface properties as dynamic drivers of particulate matter-leaf interaction and phyllosphere microbial communities'). A.C. acknowledges the Research Foundation Flanders (FWO) for her SB PhD fellowship. ; |
Approved |
Most recent IF: 4.208 |
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Call Number |
UA @ admin @ c:irua:153509 |
Serial |
5692 |
Permanent link to this record |
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Author |
Vanmeert, F.; Hendriks, E.; van der Snickt, G.; Monico, L.; Dik, J.; Janssens, K. |
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Title |
Chemical Mapping by Macroscopic X-ray Powder Diffraction (MA-XRPD) of Van Gogh's Sunflowers : identification of areas with higher degradation risk |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
57 |
Issue |
25 |
Pages |
7418-7422 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The discoloration rate of chrome yellow (CY), a class of synthetic inorganic pigments (PbCr1-xSxO4) frequently used by Van Gogh and his contemporaries, strongly depends on its sulfate content and on its crystalline structure (either monoclinic or orthorhombic). Macroscopic X-Ray powder diffraction imaging of selected areas on Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam) revealed the presence of two subtypes of CY: the light-fast monoclinic PbCrO4 (LF-CY) and the light-sensitive monoclinic PbCr1-xSxO4 (x approximate to 0.5; LS-CY). The latter was encountered in large parts of the painting (e.g., in the pale-yellow background and the bright-yellow petals, but also in the green stems and flower hearts), thus indicating their higher risk for past or future darkening. Overall, it is present in more than 50% of the CY regions. Preferred orientation of LS-CY allows observation of a significant ordering of the elongated crystallites along the direction of Van Gogh's brush strokes. |
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Place of Publication |
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Wos |
000434949200023 |
Publication Date |
2018-03-02 |
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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 |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
10 |
Open Access |
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Notes |
; The authors acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, the GOA Project Solarpaint (University of Antwerp Research Council), and the Interreg Smart*Light project. Raman analyses were performed using the European MOLAB platform, which is financially supported by the Horizon 2020 Programme (IPERION CH Grant 654028). The authors thank the staff of the Van Gogh Museum for their collaboration. ; |
Approved |
Most recent IF: 11.994 |
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Call Number |
UA @ admin @ c:irua:153185 |
Serial |
5517 |
Permanent link to this record |
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Author |
Miliani, C.; Monico, L.; Melo, M.J.; Fantacci, S.; Angelin, E.M.; Romani, A.; Janssens, K. |
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Title |
Photochemistry of Artists' Dyes and Pigments : towards better understanding and prevention of colour change in works of art |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
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Volume |
57 |
Issue |
25 |
Pages |
7324-7334 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The absorption of light gives a pigment its colour and its reason for being, but it also creates excited states, that is, new molecules with an energy excess that can be dissipated through degradation pathways. Photodegradation processes provoke long-term, cumulative and irreversible colour changes (fading, darkening, blanching) of which the prediction and prevention are challenging tasks. Of all the environmental risks that affect heritage materials, light exposure is the only one that cannot be controlled without any impact on the optimal display of the exhibit. Light-induced alterations are not only associated with the pigment itself but also with its interactions with support/binder and, in turn, are further complicated by the nature of the environmental conditions. In this Minireview we investigate how chemistry, encompassing multi-scale analytical investigations of works of art, computational modelling and physical and chemical studies contributes to improve our prediction of artwork appearance before degradation and to establish effective preventive conservation strategies. |
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Place of Publication |
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Editor |
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Wos |
000434949200006 |
Publication Date |
2018-04-26 |
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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 |
1433-7851; 0570-0833 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.994 |
Times cited |
10 |
Open Access |
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Notes |
; We acknowledge: ACS and APS for the permission to adapt Figure 1c,d; RSC to adapt Figures 1e, 3c,d and 4a; Wiley and IUCr to adapt Figures 3b and 4b-d; for the detail of a Andean textile in Figure 5, Museum of Fine Arts, Boston, USA; for the illuminated initial in Figure 6, Torre do Tombo (ANTT). Financial support from the H2020 project IPERION-CH (GA. 654028) is gratefully acknowledged. ; |
Approved |
Most recent IF: 11.994 |
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Call Number |
UA @ admin @ c:irua:153184 |
Serial |
5769 |
Permanent link to this record |
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Author |
Alvarez-Martin, A.; Janssens, K. |
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Title |
Protecting and stimulating effect on the degradation of eosin lakes. Part 1 : lead white and cobalt blue |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
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Volume |
141 |
Issue |
141 |
Pages |
51-63 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
An important problem encountered during the preservation of paintings and other artworks is the fading of the original colors due to exposure of the colorants to light. This fact is clearly evidenced in some of Vincent Van Gogh's paintings in which an organic red, eosin or geranium lake, is present. The identification of eosin and the characterization of its degradation products in paintings represents a challenge because of (i) the generally low concentration of the pigment remaining after an aging period of ca 100 years, (ii) the scarcity of the paint micro samples available for analysis and the difficulty of obtaining additional ones and (iii) the complexity of the degradation behavior of eosin when it is mixed with organic or inorganic pigments, binding media or varnish. This study presents an accelerated aging experiment of eosin paint models in order to understand better the discoloration process; more specifically the influence of different metals with which eosin forms complexes and of the presence of admixture pigments such as lead white and cobalt blue on the lightfastness of eosin is evaluated. Paint model samples were prepared using eosin, lead white, and cobalt blue in different mixing ratios and were characterized with several techniques before and after aging. The possible formation of intermediate molecular forms during the aging experiment and the influence of pigment ratios on the discoloration process were monitored at periodic intervals using a combination of LTV Visible and attenuated total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopies. Raman spectroscopy, scanning electron microscopy coupled to energy-dispersive X-ray analysis (SEM-EDX) and optical microscopy (OM) analyses were performed to gain information about the discoloration processes taking place within the paint models. Eosin precipitated on lead, aluminum and potassium/aluminum salts was used. These three lakes showed similar discoloration rates under light exposure. In contrast, the presence and relative abundance of the admixture pigments lead white and cobalt blue had a significant influence on the (speed of the) eosin discoloration process. The presence of lead white and cobalt blue appears to stimulate the eosin degradation. However, the cobalt blue shows less influence in the discoloration process, showing a protective effect during the first stages of the aging. This may be qualitatively explained in terms of the ability of lead white to scatter light towards eosin molecules and the absorption characteristics of cobalt blue in the green range of the electromagnetic spectrum, shielding eosin from incoming light. The color changes observed in the paint reconstructions are similar to discoloration phenomena visible in some Van Gogh paintings and can offer an explanation of the gradual discoloration process that took place over the years. These insights will be helpful to estimate the original hues color used/intended by the artist. |
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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 |
000439678200006 |
Publication Date |
2018-05-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.034 |
Times cited |
3 |
Open Access |
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|
Notes |
; The authors sincerely acknowledged Dr. Costanza Miliani for sharing information about the synthesis of geranium lake. The authors also acknowledged Dr. Geert van der Snickt and Gert Nuyts for the help with the aging experiments and for carrying out the SEM-EDX measurements respectively. The authors would like to acknowledge the SolarPaint project (GOA programme, Antwerp University Research Council) for financial support. ; |
Approved |
Most recent IF: 3.034 |
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Call Number |
UA @ admin @ c:irua:153087 |
Serial |
5788 |
Permanent link to this record |
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Author |
Alfeld, M.; Wahabzada, M.; Bauckhage, C.; Kersting, K.; van der Snickt, G.; Noble, P.; Janssens, K.; Wellenreuther, G.; Falkenberg, G. |
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Title |
Simplex Volume Maximization (SiVM): a matrix factorization algorithm with non-negative constrains and low computing demands for the interpretation of full spectral X-ray fluorescence imaging data |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
|
Volume |
132 |
Issue |
|
Pages |
179-184 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Technological progress allows for an ever-faster acquisition of hyperspectral data, challenging the users to keep up with interpreting the recorded data. Matrix factorization, the representation of data sets by bases (or loads) and coefficient (or score) images is long used to support the interpretation of complex data sets. We propose in this publication Simplex Volume Maximization (SiVM) for the analysis of X-ray fluorescence (XRF) imaging data sets. SiVM selects archetypical data points that represents the data set and thus provides easily understandable bases, preserves the non-negative character of XRF data sets and has low demands concerning computing resources. We apply SiVM on an XRF data set of Hans Memling's Portrait of a man from the Lespinette family from the collection of the Mauritshuis (The Hague, NL) and discuss capabilities and shortcomings of SiVM. (C) 2017 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000399845700026 |
Publication Date |
2017-02-04 |
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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 |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.034 |
Times cited |
8 |
Open Access |
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|
Notes |
; The German Federal Ministry of Education and Research (BMBF) is acknowledged for the financial support (Verbundprojekt 05K2012 POISSON: Fortschrittliche Faktorenanalyse ffir Poisson-verteilte Daten). ; |
Approved |
Most recent IF: 3.034 |
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Call Number |
UA @ admin @ c:irua:152647 |
Serial |
5830 |
Permanent link to this record |
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Author |
Florea, A.; De Jong, M.; De Wael, K. |
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Title |
Electrochemical strategies for the detection of forensic drugs |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Current opinion in electrochemistry |
Abbreviated Journal |
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Volume |
11 |
Issue |
11 |
Pages |
34-40 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Illicit drugs consumption and trafficking is spread worldwide and remains an increasing challenge for local authorities. Forensic drugs and their metabolites are released into wastewaters due to human excretion after illegal consumption of drugs and occasionally due to disposal of clandestine laboratory wastes into sewage systems, being recently classified as the latest group of emerging pollutants. Hence, it is essential to have efficient and accurate methods to detect these type of compounds in seized street samples, biological fluids and wastewaters in order to reduce and prevent trafficking and consumption and negative effects on aquatic systems. Electrochemical strategies offer a fast, portable, low-cost and accurate alternative to chromatographic and spectrometric methods, for the analysis of forensic drugs and metabolites in different matrices. Recent electrochemical strategies applied to the detection of illicit drugs in wastewaters, biological fluids and street samples are presented in this review, together with the impact of drug consumption on the environment. |
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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 |
000453710900007 |
Publication Date |
2018-07-21 |
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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 |
2451-9103; 2451-9111 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
7 |
Open Access |
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Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. The authors also acknowledge financial support from BELSPO, IOF-SBO and UAntwerp. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:152366 |
Serial |
5597 |
Permanent link to this record |
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Author |
Vanmeert, F.; de Nolf, W.; Dik, J.; Janssens, K. |
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Title |
Macroscopic X-ray powder diffraction scanning : possibilities for quantitative and depth-selective parchment analysis |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
90 |
Issue |
11 |
Pages |
6445-6452 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
At or below the surface of painted works of art, valuable information is present that provides insights into an objects past, such as the artists technique and the creative process that was followed or its conservation history but also on its current state of preservation. Various noninvasive techniques have been developed over the past 2 decades that can probe this information either locally (via point analysis) or on a macroscopic scale (e.g., full-field imaging and raster scanning). Recently macroscopic X-ray powder diffraction (MA-XRPD) mapping using laboratory X-ray sources was developed. This method can visualize highly specific chemical distributions at the macroscale (dm(2)). In this work we demonstrate the synergy between the quantitative aspects of powder diffraction and the noninvasive scanning capability of MA-XRPD highlighting the potential of the method to reveal new types of information. Quantitative data derived from a 15th/16th century illuminated sheet of parchment revealed three lead white pigments with different hydrocerussite-cerussite compositions in specific pictorial elements, while quantification analysis of impurities in the blue azurite pigment revealed two distinct azurite types: one rich in barite and one in quartz. Furthermore, on the same artifact, the depth-selective possibilities of the method that stem from an exploitation of the shift of the measured diffraction peaks with respect to reference data are highlighted. The influence of different experimental parameters on the depth-selective analysis results is briefly discussed. Promising stratigraphic information could be obtained, even though the analysis is hampered by not completely understood variations in the unit cell dimensions of the crystalline pigment phases. |
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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 |
000434893200020 |
Publication Date |
2018-04-06 |
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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 |
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 |
6 |
Open Access |
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|
Notes |
; The authors thank Incoatec GmbH for giving us the opportunity to test the I mu S Cu X-ray source. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ; |
Approved |
Most recent IF: 6.32 |
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Call Number |
UA @ admin @ c:irua:151994 |
Serial |
5702 |
Permanent link to this record |
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Author |
Vanmeert, F.; de Nolf, W.; De Meyer, S.; Dik, J.; Janssens, K. |
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Title |
Macroscopic X-ray powder diffraction scanning, a new method for highly selective chemical imaging of works of art : instrument optimization |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
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Volume |
90 |
Issue |
11 |
Pages |
6436-6444 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
In the past decade macroscopic X-ray fluorescence imaging (MA-XRF) has become established as a method for the noninvasive investigation of flat painted surfaces, yielding large scale elemental maps. MA-XRF is limited by a lack of specificity, only allowing for indirect pigment identification based on the simultaneous presence of chemical elements. The high specificity of X-ray powder diffraction (XRPD) mapping is already being exploited at synchrotron facilities for investigations at the (sub)microscopic scale, but the technique has not yet been employed using lab sources. In this paper we present the development of a novel MA-XRPD/XRF instrument based on a laboratory X-ray source. Several combinations of X-ray sources and area detectors are evaluated in terms of their spatial and angular resolution and their sensitivity. The highly specific imaging capability of the combined MA-XRPD/XRF instrument is demonstrated on a 15th/16th century illuminated manuscript directly revealing the distribution of a large number of inorganic pigments, including the uncommon yellow pigment massicot (o-PbO). The case study illustrates the wealth of new mapping information that can be obtained in a noninvasive manner using the laboratory MA-XRPD/XRF instrument. |
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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 |
000434893200019 |
Publication Date |
2018-04-06 |
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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 |
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 |
11 |
Open Access |
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Notes |
; The authors thank the persons involved at Incoatec GmbH, imXPAD SAS and Dectris Ltd. for loaning us some of their products over the past years. We acknowledge financial support from BELSPO (Brussels) S2-ART, the NWO (The Hague) Science4Arts “ReVisRembrandt” Project and GOA Project Solarpaint (University of Antwerp Research Council). Photo Copyright Geert Van der Snickt, 2008 for the photograph of the illuminated manuscript in the TOC graphic. ; |
Approved |
Most recent IF: 6.32 |
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Call Number |
UA @ admin @ c:irua:151993 |
Serial |
5701 |
Permanent link to this record |
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Author |
Dong, Y.; Chen, S.-Y.; Lu, Y.; Xiao, Y.-X.; Hu, J.; Wu, S.-M.; Deng, Z.; Tian, G.; Chang, G.-G.; Li, J.; Lenaerts, S.; Janiak, C.; Yang, X.-Y.; Su, B.-L. |
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Title |
Hierarchical MoS2@TiO2 heterojunctions for enhanced photocatalytic performance and electrocatalytic hydrogen evolution |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemistry: an Asian journal |
Abbreviated Journal |
Chem-Asian J |
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Volume |
13 |
Issue |
12 |
Pages |
1609-1615 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Hierarchical MoS2@TiO2 heterojunctions were synthesized through a one-step hydrothermal method by using protonic titanate nanosheets as the precursor. The TiO2 nanosheets prevent the aggregation of MoS2 and promote the carrier transfer efficiency, and thus enhance the photocatalytic and electrocatalytic activity of the nanostructured MoS2. The obtained MoS2@TiO2 has significantly enhanced photocatalytic activity in the degradation of rhodamineB (over 5.2times compared with pure MoS2) and acetone (over 2.8times compared with pure MoS2). MoS2@TiO2 is also beneficial for electrocatalytic hydrogen evolution (26times compared with pure MoS2, based on the cathodic current density). This work offers a promising way to prevent the self-aggregation of MoS2 and provides a new insight for the design of heterojunctions for materials with lattice mismatches. |
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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 |
000435773300011 |
Publication Date |
2018-04-10 |
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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 |
1861-4728; 1861-471x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.083 |
Times cited |
22 |
Open Access |
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Notes |
; This work was supported by the National Key R&D Program of China (2017YFC1103800), PCSIRT (IRT15R52), NSFC (U1662134, U1663225, 51472190, 51611530672, 51503166, 21706199, 21711530705), ISTCP (2015DFE52870), HPNSF (2016CFA033, 2017CFB487), and SKLPPC (PPC2016007). ; |
Approved |
Most recent IF: 4.083 |
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Call Number |
UA @ admin @ c:irua:151971 |
Serial |
5956 |
Permanent link to this record |
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Author |
Xiao, S.; Lu, Y.; Xiao, B.-Y.; Wu, L.; Song, J.-P.; Xiao, Y.-X.; Wu, S.-M.; Hu, J.; Wang, Y.; Chang, G.-G.; Tian, G.; Lenaerts, S.; Janiak, C.; Yang, X.-Y.; Su, B.-L. |
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Title |
Hierarchically dual-mesoporous TiO2 microspheres for enhanced photocatalytic properties and lithium storage |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemistry: a European journal |
Abbreviated Journal |
Chem-Eur J |
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Volume |
24 |
Issue |
50 |
Pages |
13246-13252 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Hierarchically dual‐mesoporous TiO2 microspheres have been synthesized via a solvothermal process in the presence of 1‐butyl‐3‐methylmidazolium tetrafluoroborate ([BMIm][BF4]) and diethylenetriamine (DETA) as co‐templates. Secondary mesostructured defects in the hierarchical TiO2 microspheres produce the oxygen vacancies, which not only significantly enhance the photocatalytic activity on degrading methyl blue (over 1.7 times to P25) and acetone (over 2.9 times of P25), but which also are beneficial for lithium storage. Moreover, we propose a mechanism to obtain a better understanding of the role of dual mesoporosity of TiO2 microspheres for enhancing the molecular diffusion, ion transportation and electron transformation. |
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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 |
000443804100025 |
Publication Date |
2018-06-21 |
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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 |
0947-6539 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.317 |
Times cited |
6 |
Open Access |
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Notes |
; This work is supported by the National Key R&D Program of China (2017YFC1103800), the Program for Changjiang Scholars and Innovative Research Team in University (IRT 15R52), the National Natural Science Foundation of China (U1662134, U1663225, 51472190, 51611530672, 51503166, 21706199, 21711530705), the International Science & Technology Cooperation Program of China (2015DFE52870), the Natural Science Foundation of Hubei Province (2016CFA033, 2017CFB487), the Open Project Program of State Key Laboratory of Petroleum Pollution Control (PPC2016007), and the CNPC Research Institute of Safety and Environmental Technology. ; |
Approved |
Most recent IF: 5.317 |
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Call Number |
UA @ admin @ c:irua:151812 |
Serial |
5957 |
Permanent link to this record |
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Author |
Kuckova, S.; Hamidi-Asl, E.; Matulkova, I.; Hynek, R.; De Wael, K.; Sanyova, J.; Janssens, K. |
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Title |
Technoques and applications of Surface-Enhanced Raman Scattering Spectroscopy (SERSS) focused on cultural heritage |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemické listy |
Abbreviated Journal |
Chem Listy |
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Volume |
112 |
Issue |
5 |
Pages |
312-316 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
The review is devoted to a modern method of vibrational spectroscopy – surface enhanced Raman spectroscopy Its principle and some of its special variants (imunnoSERS and TERS (Tip-Enhanced Raman Spectroscopy)) are described m a simpinified manner Wide application possibilities are demonstrated on selected examples from its application m culturinl heritage. |
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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 |
0009-2770; 1213-7103 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
0.387 |
Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 0.387 |
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Call Number |
UA @ admin @ c:irua:151616 |
Serial |
5869 |
Permanent link to this record |
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Author |
Hirayama, A.; Abe, Y.; van Loon, A.; De Keyser, N.; Noble, P.; Vanmeert, F.; Janssens, K.; Tantrakarn, K.; Taniguchi, K.; Nakai, I. |
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Title |
Development of a new portable X-ray powder diffractometer and its demonstration to on-site analysis of two selected old master paintings from the Rijksmuseum |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
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Volume |
138 |
Issue |
138 |
Pages |
266-272 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
A portable X-ray powder diffractometer (p-XRD) PT-APXRD III has been developed for onsite analysis of paintings and archaeological samples. By using a Cu anode X-ray tube and a silicon drift diode (SDD) detector, diffraction patterns with a high signalnoise (S/N) ratio can be recorded. The X-ray tube can be operated at a maximum voltage of 60 kV, which makes it possible to simultaneously record X-ray fluorescence spectra up to the high-energy region. The total weight of this instrument is 16 kg, which can be carried anywhere and the goniometer unit (5.6 kg) can be placed on a tripod for analysis of mural paintings. We brought the instrument to the Rijksmuseum in the Netherlands to examine its applicability for the analysis of oil paintings. We successfully analyzed two seventeenthcentury oil paintings by Johannes Vermeer and Jan Davidsz de Heem (copy after). Ultramarine blue, leadtin yellow type I, and Naples yellow were identified from the diffraction patterns, demonstrating the high practicality of this instrument. Furthermore, it was found from the SEM-EDX analysis of a paint cross section that the yellow pigment was applied in separate layers rather than being mixed. This diffractometer will be commercially available in the near future and will have many applications in the field of material analysis. (C) 2018 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000428103000030 |
Publication Date |
2018-01-04 |
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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 |
0026-265x; 0026-265x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.034 |
Times cited |
2 |
Open Access |
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Notes |
; This research was conducted with the support of the JSPS (Tokyo, Japan)-FWO (Brussels, Belgium) bilateral exchange project. ; |
Approved |
Most recent IF: 3.034 |
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Call Number |
UA @ admin @ c:irua:151565 |
Serial |
5575 |
Permanent link to this record |
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Author |
van der Snickt, G.; Legrand, S.; Slama, I.; Van Zuien, E.; Gruber, G.; Van der Stighelen, K.; Klaassen, L.; Oberthaler, E.; Janssens, K. |
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Title |
In situ macro X-ray fluorescence (MA-XRF) scanning as a non-invasive tool to probe for subsurface modifications in paintings by PP Rubens |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
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Volume |
138 |
Issue |
138 |
Pages |
238-245 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
Within the last decade, the established synchrotron- and laboratory-based micro-XRF scanning technology inspired the development of mobile instruments that allow performing in situ experiments on paintings on a macro scale. Since the development of the first mobile scanner at the start of this decade, this chemical imaging technique has brought new insights with respect to several iconic paintings, especially in cases when standard imaging techniques such as X-Ray Radiography (XRR) or Infrared Refiectography (IRR) yielded ambiguous results. The ability of scanning MA-XRF to visualise the distribution of elements detected at and below the paint surface renders this spectrometric method particularly helpful for studying painting techniques and revealing materials that remain hidden below the paint surface. The latter aspect is especially relevant for the technical study of works by Pieter Paul Rubens (1577-1640) as this highly productive seventeenth century master is particularly renowned for the continuous application of modifications during (and even after) the entire course of the creative process. In this work, the added value of MA-XRF scanning experiments for visualising these subsurface features is exemplified by interpreting the chemical images obtained on three of Rubens' key works. Special attention is given to three types of adjustments that are particularly relevant for the technical study of Rubens' oeuvre: (1) compositional changes ('pentimenti'), exemplified by results obtained on The Portrait of Helene Fourment (ca. 1638), (2) extensions to the support ('Anstlickungen.), illustrated by imaging experiments performed on the Venus Frigida (1614) and (3) Rubens' intriguing halos around flesh tones, as found amongst others in The Incredulity of Saint Thomas (1613). The ensuing insights in the paint stratigraphy and the underlying supporting structure illustrate the potential of MA-XRF scanning for the non-invasive, comparative study of Rubens' oeuvre. The results do not only augment the understanding of the complex genesis of Rubens' works of art and his efficient painting technique, but prove valuable during conservation treatments as well, as addressed in this paper. (C) 2018 Elsevier B.V. All rights reserved. |
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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 |
000428103000027 |
Publication Date |
2018-01-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
|
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.034 |
Times cited |
5 |
Open Access |
|
|
Notes |
; ; |
Approved |
Most recent IF: 3.034 |
|
Call Number |
UA @ admin @ c:irua:151564 |
Serial |
5657 |
Permanent link to this record |
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Author |
Legrand, S.; Ricciardi, P.; Nodari, L.; Janssens, K. |
|
Title |
Non-invasive analysis of a 15th century illuminated manuscript fragment: point-based vs imaging spectroscopy |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
|
Volume |
138 |
Issue |
138 |
Pages |
162-172 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
Illuminated manuscript fragments are some of the best preserved objects of Western cultural heritage. Therefore, scholars are limited to non-invasive – often point-based – methods, to answer questions on material usage, technique, origin and previous treatments. These powerful methods yield specific information; however, the information is limited to the number of points analyzed. Imaging spectroscopies such as MA-XRF and MA-rFTIR combine specificity with the power of imaging, resulting in distribution images that are interpretable by non-spectroscopists and the public at large. In this paper the possible added value of using imaging spectroscopy is discussed. Do these methods yield the same results as an extensive point-based spectroscopic campaign and can they bring novel information? As a case study, a 15th century illuminated manuscript fragment is employed in order to explore the differences between these approaches and present an inventory of their advantages and limitations. (C) 2018 Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000428103000019 |
Publication Date |
2018-01-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.034 |
Times cited |
12 |
Open Access |
|
|
Notes |
; The authors wish to thank Dr. Stella Panayotova, Keeper of Manuscripts and Printed Books at the Fitzwilliam Museum, for allowing technical analysis of the manuscript fragment, and Dr. Suzanne Reynolds, Assistant Keeper of Manuscripts and Printed Books, for crucial help in identifying the text on the reverse of the fragment and its significance. We also wish to thank Prof. Andrew Beeby and Dr. Catherine Nicholson for their complementary Raman analyses. The warm hospitality of the Hamilton Kerr Institute is also gratefully acknowledged. The Esmee Fairbairn Collections Fund and Cambridge University's Returning Carers Scheme provided funding for part of this research. SL and KJ acknowledge support from project METOX (contract BR/165/A6/MetOx), BELSPO, Brussels. ; |
Approved |
Most recent IF: 3.034 |
|
Call Number |
UA @ admin @ c:irua:151563 |
Serial |
5749 |
Permanent link to this record |
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Author |
De Jong, M.; Florea, A.; Eliaerts, J.; Van Durme, F.; Samyn, N.; De Wael, K. |
|
Title |
Tackling poor specificity of cocaine color tests by electrochemical strategies |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
Volume |
90 |
Issue |
11 |
Pages |
6811-6819 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
This paper presents electrochemical strategies for the fast screening of cocaine and most common cutting agents found in seized drug samples. First, a study on the performance of Scott color tests on cocaine and a wide range of cutting agents is described. The cutting agents causing false positive or false negative results when in mixture with cocaine are identified. To overcome the lack of specificity of color tests, we further propose a fast screening strategy by means of square wave voltammetry on disposable graphite screen printed electrodes, which reveals the unique fingerprint of cocaine and cutting agents. By employing a forward and backward scan and by a dual pH strategy, we enrich the electrochemical fingerprint and enable the simultaneous detection of cocaine and cutting agents. The effectiveness of the developed strategies was tested for the detection of cocaine in seized cocaine samples and compared with the color tests. Moreover, we prove the usefulness of square wave voltammetry for predicting possible interfering agents in color tests, based on the reduction peak of cobalt thiocyanate. The developed electrochemical strategies allow for a quick screening of seized cocaine samples resulting in a selective identification of drugs and cutting agents. |
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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 |
000434893200066 |
Publication Date |
2018-05-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
6.32 |
Times cited |
7 |
Open Access |
|
|
Notes |
; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by Grants BR/314 /PI/APTADRU and IOF-SBO. ; |
Approved |
Most recent IF: 6.32 |
|
Call Number |
UA @ admin @ c:irua:151316 |
Serial |
5867 |
Permanent link to this record |
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Author |
Tarakanov, P.A.; Tarakanova, E.N.; Dorovatovskii, P.V.; Zubavichus, Y.V.; Khrustalev, V.N.; Trashin, S.A.; De Wael, K.; Neganova, M.E.; Mischenko, D.V.; Sessler, J.L.; Stuzhin, P.A.; Pushkarev, V.E.; Tomilova, L.G. |
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Title |
Optical readout of controlled monomer-dimer self-assembly |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
|
|
Volume |
47 |
Issue |
40 |
Pages |
14169-14173 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
5,7-Substituted 1,4-diazepinoporphyrazine magnesium(II) complexes were synthesized via Mg(II)-alkoxide templated macrocyclization. A single crystal growth synchrotron diffraction analysis permitted what is to our knowledge the first structural characterization of a 1,4-diazepinoporphyrazine. It exists as a dimer in the solid state. In silico calculations supported by solution phase spectral studies involving a series of representative derivatives, provided insights into the factors governing dimerization of 1,4-diazepinoporphyrazines. The present 1,4-diazepinoporphyrazines serve as useful probes for understanding the determinants that guide dimermonomer equilibria and the self-assembly of phthalocyanine derivatives. |
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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 |
000447708900005 |
Publication Date |
2018-04-10 |
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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 |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
4 |
Open Access |
|
|
Notes |
; We thank Dr Alexander V. Chernyak for recording the NMR spectra. Synthetic and optical spectroscopic studies in this work were supported by the RSF (Grant 17-73-10413). NMR studies were supported by the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grant MD-2991.2017.3). SR-XRD studies were supported by the RUDN University Program “5-100”. We also acknowledge support of electrochemical, in vitro and in vivo studies by the State Assignment (Theme 45.5 Creation of compounds with given physicochemical properties) and the facilities provided by the Center of Collective Use of IPAC RAS (Chernogolovka, Russia). Single-crystal X-ray measurements have been performed at the unique scientific facility Kurchatov Synchrotron Radiation Source supported by the Ministry of Education and Science of the Russian Federation (project code RFMEFI61917X0007). ; |
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:151294 |
Serial |
5755 |
Permanent link to this record |
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Author |
Florea, A.; Cowen, T.; Piletsky, S.; De Wael, K. |
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Title |
Polymer platforms for selective detection of cocaine in street samples adulterated with levamisole |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Talanta : the international journal of pure and applied analytical chemistry |
Abbreviated Journal |
Talanta |
|
Volume |
186 |
Issue |
186 |
Pages |
362-367 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
Accurate drug detection is of utmost importance for fighting against drug abuse. With a high number of cutting agents and adulterants being added to cut or mask drugs in street powders the number of false results is increasing. We demonstrate for the first time the usefulness of employing polymers readily synthesized by electrodeposition to selectively detect cocaine in the presence of the commonly used adulterant levamisole. The polymers were selected by computational modelling to exhibit high binding affinity towards cocaine and deposited directly on the surface of graphene-modified electrodes via electropolymerization. The resulting platforms allowed a distinct electrochemical signal for cocaine, which is otherwise suppressed by levamisole. Square wave voltammetry was used to quantify cocaine alone and in the presence of levamisole. The usefulness of the platforms was demonstrated in the screening of real street samples. |
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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 |
000435048800049 |
Publication Date |
2018-04-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0039-9140; 1873-3573 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.162 |
Times cited |
9 |
Open Access |
|
|
Notes |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement no. 753223 Narcoreader. This work was also supported by IOF-SBO (UAntwerp). The authors thank Gert Nuyts for the help with SEM analyses. ; |
Approved |
Most recent IF: 4.162 |
|
Call Number |
UA @ admin @ c:irua:151250 |
Serial |
5777 |
Permanent link to this record |
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Author |
Vermeulen, M.; Janssens, K.; Sanyova, J.; Rahemi, V.; McGlinchey, C.; De Wael, K. |
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Title |
Assessing the stability of arsenic sulfide pigments and influence of the binding media on their degradation by means of spectroscopic and electrochemical techniques |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Microchemical journal |
Abbreviated Journal |
Microchem J |
|
Volume |
138 |
Issue |
138 |
Pages |
82-91 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
In this paper, we used the semiconducting and lightfastness properties of synthetic and mineral arsenic sulfide pigments to study their stability by means of electrochemical and microfadometric techniques. A combination of these techniques shows that in the early stage of the degradation process, amorphous arsenic sulfides are more stable than both crystalline forms, while upon longer exposure time, amorphous pigments will fade more than both mineral pigments, making it less suitable. While the stability study was carried out on unbound pigments, the influence of the organic binder on the relative degradation of the arsenic sulfide pigments was investigated through a multi-analytical approach on pigment/binder mock-up paint samples. For this purpose, the formation of arsenic trioxide was assessed by micro Fourier transform infrared (μ-FTIR) spectroscopy while the influence of the binder on the formation of sulfates was studied by means of synchrotron radiation X-ray near edge structure (μ-XANES). Both techniques elucidate a higher stability of all pigments in gum arabic while the use of egg yolk as binder leads to the most degradation, most likely due to its sulfur-rich composition. In the context of the degradation of arsenic sulfide pigments, other binders such as animal glue, egg white or linseed oil show an intermediate impact. |
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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 |
000428103000010 |
Publication Date |
2018-01-06 |
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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 |
0026-265x; 0026-265x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.034 |
Times cited |
4 |
Open Access |
|
|
Notes |
; This research is made possible with the support of the Belgian Science Policy Office (BELSPO, Brussels) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (grant number SD/RI/04A). We gratefully acknowledge Megane Willems (Institut Paul-Lambin) for her help with mu-FFIR analyses and realization of the mock-up paint samples. We acknowledge the Paul Scherrer Institut, Villigen, Switzerland for provision of synchrotron radiation beamtime at beamline Phoenix of the SLS. ; |
Approved |
Most recent IF: 3.034 |
|
Call Number |
UA @ admin @ c:irua:150149 |
Serial |
5482 |
Permanent link to this record |
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Author |
Peng, L.; Dai, X.; Liu, Y.; Sun, J.; Song, S.; Ni, B.-J. |
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Title |
Model-based assessment of estrogen removal by nitrifying activated sludge |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Chemosphere |
Abbreviated Journal |
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Volume |
197 |
Issue |
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Pages |
430-437 |
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Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Complete removal of estrogens such as estrone (E1), estradiol (E2), estriol (E3) and ethinylestradiol (EE2) in wastewater treatment is essential since their release and accumulation in natural water bodies are giving rise to environment and health issues. To improve our understanding towards the estrogen bioremediation process, a mathematical model was proposed for describing estrogen removal by nitrifying activated sludge. Four pathways were involved in the developed model: i) biosorption by activated sludge flocs; ii) cometabolic biodegradation linked to ammonia oxidizing bacteria (AOB) growth; iii) non growth biodegradation by AOB; and iv) biodegradation by heterotrophic bacteria (HB). The degradation kinetics was implemented into activated sludge model (ASM) framework with consideration of interactions between substrate update and microorganism growth as well as endogenous respiration. The model was calibrated and validated by fitting model predictions against two sets of batch experimental data under different conditions. The model could satisfactorily capture all the dynamics of nitrogen, organic matters (COD), and estrogens. Modeling results suggest that for El, E2 and EE2, AOB-linked biodegradation is dominant over biodegradation by HB at all investigated COD dosing levels. However, for E3, the increase of COD dosage triggers a shift of dominant pathway from AOB biodegradation to HB biodegradation. Adsorption becomes the main contributor to estrogen removal at high biomass concentrations. (C) 2018 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000426231900049 |
Publication Date |
2018-01-10 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0045-6535; 1879-1298 |
ISBN |
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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:149842 |
Serial |
8259 |
Permanent link to this record |
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Author |
van Espen, P.; Janssens, K.; Nobels, J. |
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Title |
AXIL-PC, software for the analysis of complex-x-ray spectra |
Type |
A1 Journal article |
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Year |
1986 |
Publication |
Chemometrics and intelligent laboratory systems |
Abbreviated Journal |
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Volume |
1 |
Issue |
1 |
Pages |
109-114 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3) |
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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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Language |
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Wos |
A1986K579000015 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0169-7439 |
ISBN |
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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:149781 |
Serial |
5487 |
Permanent link to this record |
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Author |
Janssens, K.; van Espen, P. |
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Title |
A general-purpose interface between fortran and the low-level functions of the ibm-pc |
Type |
A1 Journal article |
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Year |
1988 |
Publication |
Trends in analytical chemistry |
Abbreviated Journal |
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Volume |
7 |
Issue |
4 |
Pages |
128-130 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3) |
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Abstract |
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Address |
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Corporate Author |
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Publisher |
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Place of Publication |
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Wos |
A1988M999800003 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0165-9936 |
ISBN |
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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:149778 |
Serial |
5450 |
Permanent link to this record |
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Author |
Janssens, K.; Nobels, J.; van Espen, P. |
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Title |
PC-MCA : a software package for the acquisition and processing of spectral data |
Type |
A1 Journal article |
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Year |
1988 |
Publication |
Chemometrics and intelligent laboratory systems |
Abbreviated Journal |
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Volume |
3 |
Issue |
4 |
Pages |
335-341 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3) |
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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 |
A1988P260100012 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
0169-7439 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:149776 |
Serial |
5768 |
Permanent link to this record |
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Author |
Janssens, K.; Dorrine, W.; van Espen, P. |
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Title |
The development process of an expert system for the automated interpretation of large epma data sets |
Type |
A1 Journal article |
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Year |
1988 |
Publication |
Chemometrics and intelligent laboratory systems |
Abbreviated Journal |
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Volume |
4 |
Issue |
2 |
Pages |
147-161 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3) |
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Abstract |
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Address |
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Corporate Author |
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Publisher |
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Place of Publication |
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Language |
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Wos |
A1988Q148500007 |
Publication Date |
2002-07-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0169-7439 |
ISBN |
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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:149775 |
Serial |
5872 |
Permanent link to this record |
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Author |
De Jong, M.; Florea, A.; de Vries, A.-M.; van Nuijs, A.L.N.; Covaci, A.; Van Durme, F.; Martins, J.C.; Samyn, N.; De Wael, K. |
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Title |
Levamisole : a common adulterant in cocaine street samples hindering electrochemical detection of cocaine |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
|
Volume |
90 |
Issue |
8 |
Pages |
5290-5297 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
|
Abstract |
The present work investigates the electrochemical determination of cocaine in the presence of levamisole, one of the most common adulterants found in cocaine street samples. Levamisole misleads cocaine color tests, giving a blue color (positive test) even in the absence of cocaine. Moreover, the electrochemical detection of cocaine is also affected by the presence of levamisole, with a suppression of the oxidation signal of cocaine. When levamisole is present in the sample in ratios higher than 1:1, the cocaine signal is no longer detected, thus leading to false negative results. Mass spectrometry and nuclear magnetic resonance were used to investigate if the signal suppression is due to the formation of a complex between cocaine and levamisole in bulk solution. Strategies to eliminate this suppressing effect are further suggested in this manuscript. In a first approach, the increase of the pH of the sample solution from pH 7 to pH 12 allowed the voltammetric determination of cocaine in the presence of levamisole in a concentration range from 10 to 5000 μM at nonmodified graphite disposable electrodes with a detection limit of 5 μM. In a second approach, the graphite electrode was cathodically pretreated, resulting in the presence of oxidation peaks of both cocaine and levamisole, with a detection limit for cocaine of 3 μM over the linear range of concentrations from 10 to 2500 μM. Both these strategies have been successfully applied for the simultaneous detection of cocaine and levamisole in three street samples on unmodified graphite disposable electrodes. |
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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 |
000430512200049 |
Publication Date |
2018-02-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
6.32 |
Times cited |
8 |
Open Access |
|
|
Notes |
; This project has received funding from the European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement No. 753223 Narcoreader. This work was also supported by BR/314/PI/ APTADRU Project and IOF-SBO (UAntwerp). Alexander van Nuijs acknowledges the Research Foundation-Flanders (FWO) for his postdoctoral fellowship. ; |
Approved |
Most recent IF: 6.32 |
|
Call Number |
UA @ admin @ c:irua:149528 |
Serial |
5693 |
Permanent link to this record |