| Records |
| Author |
Ayalew, E.; Janssens, K.; De Wael, K. |
| Title |
Unraveling the reactivity of minium towards bicarbonate and the role of lead oxides therein |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Analytical chemistry |
Abbreviated Journal  |
Anal Chem |
| Volume |
88 |
Issue |
3 |
Pages |
1564-1569 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Understanding the reactivity of (semiconductor) pigments provides vital information on how to improve conservation strategies for works of art in order to avoid rapid degradation of the pigments. This study focuses on the photoactivity of minium (Pb3O4), a semiconductor pigment, that gives rise to strong discoloration phenomena upon exposure to various environmental conditions. To demonstrate its photoactivity, an electrochemical setup with minium-modified graphite electrode (C|Pb3O4) was used. It is confirmed that minium is a p-type semiconductor which is photoactive during illumination and becomes inactive in the dark. Raman measurements confirm the formation of the degradation products. The photoactivity of a semiconductor pigment is partly defined by the presence of lead oxide (PbO) impurities; these introduce new states in the original band gap. It will be experi-mentally evidenced that the presence of PbO particles in minium leads to an upward shift of the valence band that reduces the band gap. Thus, upon photoexcitation, the electron/hole separation is more easily initialized. The PbO/Pb3O4 composite electrodes demonstrate a higher reductive photocurrent compared to the photocurrent registered at pure PbO or Pb3O4 modified electrodes. Upon exposure to light with energy close to and above the band gap, electrons are excited from the valence band to the conduction band to initialize the reduction of Pb(IV) to Pb(II), resulting in the initial formation of PbO. However in the presence of bicarbonate ions, a significantly higher photoreduction current is recorded since the PbO reacts further to form hydrocerussite. Therefore the presence of bicarbonates in the environment stimulates the photodecomposition process of minium and plays an important role in the degradation process. |
| 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 |
000369471100014 |
Publication Date |
2015-12-31 |
| Series Editor |
|
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 |
9 |
Open Access |
|
| Notes |
; The authors acknowledge Sanne Aerts from the Laboratory of Adsorption and Catalysis (LADCA) of the University of Antwerp for her help with the UV-vis-DR. Financial support from the SOLARPAINT BOF-GOA project (University of Antwerp Research Council) is acknowledged. The authors are also indebted to F. Vanmeert for performing the XRD measurements. ; |
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:129963 |
Serial |
5888 |
| Permanent link to this record |
| |
|
| |
| Author |
De Wael, K.; Daems, D.; Van Camp, G.; Nagels, L.J. |
| Title |
The use of potentiometric sensors to study (bio)molecular interactions |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
84 |
Issue |
11 |
Pages |
4921-4927 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Potentiometric sensors were used to study molecular interactions in liquid environments, with sensorgram methodology. This is demonstrated with a lipophilic rubber-, and with a collagen based hydrogel sensor coating. The investigated molecules were promazine and tartaric acid respectively. The sensors were placed in a hydrodynamic wall jet system for the recording of sensorgrams. mV sensor responses were first converted to a signal, expressing the concentration of adsorbed organic ions. Using a linearization method, a pseudo first order kinetic model of adsorption was shown to fit the experimental results perfectly. Kass, kon and koff values were calculated.. The technique can be used over 4 decades of concentration, and it is very sensitive to low MW compounds as well as to multiply charged large biomolecules. This study is the first to demonstrate the application of potentiometric sensors as an alternative and complement to SPR methods. |
| 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 |
000304783100041 |
Publication Date |
2012-04-28 |
| Series Editor |
|
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 |
10 |
Open Access |
|
| Notes |
; Financial support for this work was provided by the University of Antwerp by granting D.D. a BOF interdisciplinary research project. We thank J. Everaert for his help in interpreting the results. K.D.W. and D.D. contributed equally to this work. ; |
Approved |
Most recent IF: 6.32; 2012 IF: 5.695 |
| Call Number |
UA @ admin @ c:irua:97520 |
Serial |
5898 |
| Permanent link to this record |
| |
|
| |
| Author |
Dik, J.; Janssens, K.; van der Snickt, G.; van der Loeff, L.; Rickers, K.; Cotte, M. |
| Title |
Visualization of a lost painting by Vincent van Gogh using synchrotron radiation based X-ray fluorescence elemental mapping |
Type |
A1 Journal article |
| Year |
2008 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
80 |
Issue |
16 |
Pages |
6436-6442 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Vincent van Gogh (1853−1890), one of the founding fathers of modern painting, is best known for his vivid colors, his vibrant painting style, and his short but highly productive career. His productivity is even higher than generally realized, as many of his known paintings cover a previous composition. This is thought to be the case in one-third of his early period paintings. Van Gogh would often reuse the canvas of an abandoned painting and paint a new or modified composition on top. These hidden paintings offer a unique and intimate insight into the genesis of his works. Yet, current museum-based imaging tools are unable to properly visualize many of these hidden images. We present the first-time use of synchrotron radiation based X-ray fluorescence mapping, applied to visualize a womans head hidden under the work Patch of Grass by Van Gogh. We recorded decimeter-scale, X-ray fluorescence intensity maps, reflecting the distribution of specific elements in the paint layers. In doing so we succeeded in visualizing the hidden face with unprecedented detail. In particular, the distribution of Hg and Sb in the red and light tones, respectively, enabled an approximate color reconstruction of the flesh tones. This reconstruction proved to be the missing link for the comparison of the hidden face with Van Goghs known paintings. Our approach literally opens up new vistas in the nondestructive study of hidden paint layers, which applies to the oeuvre of Van Gogh in particular and to old master paintings in general. |
| 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 |
000258448100039 |
Publication Date |
2008-07-29 |
| Series Editor |
|
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 |
178 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.32; 2008 IF: 5.712 |
| Call Number |
UA @ admin @ c:irua:74466 |
Serial |
5906 |
| Permanent link to this record |
| |
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| |
| Author |
Schram, J.; Parrilla, M.; Sleegers, N.; Samyn, N.; Bijvoets, S.M.; Heerschop, M.W.J.; van Nuijs, A.L.N.; De Wael, K. |
| Title |
Identifying Electrochemical Fingerprints of Ketamine with Voltammetry and Liquid Chromatography–Mass Spectrometry for Its Detection in Seized Samples |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
92 |
Issue |
19 |
Pages |
13485-13492 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
| Abstract |
Herein, a straightforward electrochemical approach for the determination of ketamine in street samples and seizures is presented by employing screen-printed electrodes (SPE). Square wave voltammetry (SWV) is used to study the electrochemical behavior of the illicit drug, thus profiling the different oxidation states of the substance at different pHs. Besides, the oxidation pathway of ketamine on SPE is investigated for the first time with liquid chromatography–high-resolution mass spectrometry. Under the optimized conditions, the calibration curve of ketamine at buffer solution (pH 12) exhibits a sensitivity of 8.2 μA μM–1, a linear relationship between 50 and 2500 μM with excellent reproducibility (RSD = 2.2%, at 500 μM, n = 7), and a limit of detection (LOD) of 11.7 μM. Subsequently, binary mixtures of ketamine with adulterants and illicit drugs are analyzed with SWV to investigate the electrochemical fingerprint. Moreover, the profile overlapping between different substances is addressed by the introduction of an electrode pretreatment and the integration of a tailor-made script for data treatment. Finally, the approach is tested on street samples from forensic seizures. Overall, this system allows for the on-site identification of ketamine by law enforcement agents in an easy-to-use and rapid manner on cargos and seizures, thereby disrupting the distribution channel and avoiding the illicit drug reaching the end-user. |
| 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 |
000580426800091 |
Publication Date |
2020-10-06 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
|
Edition |
|
| ISSN |
0003-2700 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
|
| Notes |
Universiteit Antwerpen; H2020 Societal Challenges, 833787 ; Fonds Wetenschappelijk Onderzoek, 1S3765817N 1SB8120N ; |
Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
| Call Number |
AXES @ axes @c:irua:170523 |
Serial |
6435 |
| Permanent link to this record |
| |
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| |
| Author |
Aghaei, M.; Bogaerts, A. |
| Title |
Flowing Atmospheric Pressure Afterglow for Ambient Ionization: Reaction Pathways Revealed by Modeling |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
93 |
Issue |
17 |
Pages |
6620-6628 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
We describe the plasma chemistry in a helium flowing atmospheric pressure afterglow (FAPA) used for analytical spectrometry, by means of a quasione-dimensional (1D) plasma chemical kinetics model. We study the effect of typical impurities present in the feed gas, as well as the afterglow in ambient humid air. The model provides the species density profiles in the discharge and afterglow regions and the chemical pathways. We demonstrate that H, N, and O atoms are formed in the discharge region, while the dominant reactive neutral species in the afterglow are O3 and NO. He* and He2* are responsible for Penning ionization of O2, N2, H2O, H2, and N, and especially O and H atoms. Besides, He2+ also contributes to ionization of N2, O2, H2O, and O through charge transfer reactions. From the pool of ions created in the discharge, NO+ and (H2O)3H+ are the dominant ions in the afterglow. Moreover, negatively charged clusters, such as NO3H2O− and NO2H2O−, are formed and their pathway is discussed as well. Our model predictions are in line with earlier observations in the literature about the important reagent ions and provide a comprehensive overview of the underlying pathways. The model explains in detail why helium provides a high analytical sensitivity because of high reagent ion formation by both Penning ionization and charge transfer. Such insights are very valuable for improving the analytical performance of this (and other) ambient desorption/ionization source(s). |
| 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 |
000648505900008 |
Publication Date |
2021-05-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-2700 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.32 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
Fonds Wetenschappelijk Onderzoek, 6713 ; The authors gratefully acknowledge financial support from the Fonds voor Wetenschappelijk Onderzoek (FWO) grant number 6713. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (Department EWI), and the UA. The authors also thank J. T. Shelley for providing experimental data for the gas velocity behind the anode disk and before the mass spectrometer interface, to validate our model. |
Approved |
Most recent IF: 6.32 |
| Call Number |
PLASMANT @ plasmant @c:irua:178126 |
Serial |
6762 |
| Permanent link to this record |
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| |
| Author |
Neven, L.; Barich, H.; Ching, H.Y.V.; Khan, S.U.; Colomier, C.; Patel, H.H.; Gorun, S.M.; Verbruggen, S.; Van Doorslaer, S.; De Wael, K. |
| Title |
Correlation between the fluorination degree of perfluorinated zinc phthalocyanines, their singlet oxygen generation ability, and their photoelectrochemical response for phenol sensing |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
94 |
Issue |
13 |
Pages |
5221-5230 |
| Keywords |
A1 Journal article; Organic synthesis (ORSY); Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
| Abstract |
Electron-withdrawing perfluoroalkyl peripheral groups grafted on phthalocyanine (Pc) macrocycles improve their single-site isolation, solubility, and resistance to self-oxidation, all beneficial features for catalytic applications. A high degree of fluorination also enhances the reducibility of Pcs and could alter their singlet oxygen (1O2) photoproduction. The ethanol/toluene 20:80 vol % solvent mixture was found to dissolve perfluorinated FnPcZn complexes, n = 16, 52, and 64, and minimize the aggregation of the sterically unencumbered F16PcZn. The 1O2 production ability of FnPcZn complexes was examined using 9,10-dimethylanthracene (DMA) and 2,2,6,6-tetramethylpiperidine (TEMP) in combination with UV–vis and electron paramagnetic resonance (EPR) spectroscopy, respectively. While the photoreduction of F52PcZn and F64PcZn in the presence of redox-active TEMP lowered 1O2 production, DMA was a suitable 1O2 trap for ranking the complexes. The solution reactivity was complemented by solid-state studies via the construction of photoelectrochemical sensors based on TiO2-supported FnPcZn, FnPcZn|TiO2. Phenol photo-oxidation by 1O2, followed by its electrochemical reduction, defines a redox cycle, the 1O2 production having been found to depend on the value of n and structural features of the supported complexes. Consistent with solution studies, F52PcZn was found to be the most efficient 1O2 generator. The insights on reactivity testing and structural–activity relationships obtained may be useful for designing efficient and robust sensors and for other 1O2-related applications of FnPcZn. |
| 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 |
000786254500002 |
Publication Date |
2022-03-22 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 7.4 |
| Call Number |
UA @ admin @ c:irua:187522 |
Serial |
7141 |
| Permanent link to this record |
| |
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| |
| Author |
Girard-Sahun, F.; Lefrancois, P.; Badets, V.; Arbault, S.; Clement, F. |
| Title |
Direct sensing of superoxide and its relatives reactive oxygen and nitrogen species in phosphate buffers during cold atmospheric plasmas exposures |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
94 |
Issue |
14 |
Pages |
5555-5565 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
This study aims at sensing in situ reactive oxygen and nitrogen species (RONS) and specifically superoxide anion (O-2(center dot-)) in aqueous buffer solutions exposed to cold atmospheric plasmas (CAPs). CAPs were generated by ionizing He gas shielded with variable N-2/O-2 mixtures. Thanks to ultramicroelectrodes protected against the high electric fields transported by the ionization waves of CAPs, the production of superoxide and several RONS was electrochemically directly detected in liquids during their plasma exposure. Complementarily, optical emissive spectroscopy (OES) was used to study the plasma phase composition and its correlation with the chemistry in the exposed liquid. The specific production of O-2(center dot-), a biologically reactive redox species, was analyzed by cyclic voltammetry (CV), in both alkaline (pH 11), where the species is fairly stable, and physiological (pH 7.4) conditions, where it is unstable. To understand its generation with respect to the plasma chemistry, we varied the shielding gas composition of CAPs to directly impact on the RONS composition at the plasma-liquid interface. We observed that the production and accumulation of RONS in liquids, including O(2)(center dot-)depends on the plasma composition, with N-2-based shieldings providing the highest superoxide concentrations (few 10s of micromolar at most) and of its derivatives (hundreds of micromolar). In situ spectroscopic and electrochemical analyses provide a high resolution kinetic and quantitative understanding of the interactions between CAPs and physiological solutions for biomedical applications. |
| 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 |
000805334400013 |
Publication Date |
2022-03-28 |
| 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 |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 7.4 |
| Call Number |
UA @ admin @ c:irua:189093 |
Serial |
7143 |
| Permanent link to this record |
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| Author |
Khan, S.U.; Trashin, S.; Beltran, V.; Korostei, Y.S.; Pelmus, M.; Gorun, S.M.; Dubinina, T., V.; Verbruggen, S.W.; De Wael, K. |
| Title |
Photoelectrochemical behavior of phthalocyanine-sensitized TiO₂ in the presence of electron-shuttling mediators |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
94 |
Issue |
37 |
Pages |
12723-12731 |
| Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
| Abstract |
Dye-sensitized TiO(2 )has found many applications for dye sensitized solar cells (DSSC), solar-to-chemical energy conversion, water/air purification systems, and (electro)chemical sensors. We report an electrochemical system for testing dye-sensitized materials that can be utilized in photoelectrochemical (PEC) sensors and energy conversion. Unlike related systems, the reported system does not require a direct electron transfer from semiconductors to electrodes. Rather, it relies on electron shuttling by redox mediators. A range of model photocatalytic materials were prepared using three different TiO2 materials (P25, P90, and PC500) and three sterically hindered phthalocyanines (Pcs) with electron-rich tert-butyl substituents (t-Bu4PcZn, t-Bu4PcAlCl, and t-Bu4PcH2). The materials were compared with previously developed TiO(2 )modified by electron-deficient, also sterically hindered fluorinated phthalocyanine F64PcZn, a singlet oxygen (O-1(2)) producer, as well as its metal-free derivative, F64PcH2. The PEC activity depended on the redox mediator, as well as the type of TiO2 and Pc. By comparing the responses of one-electron shuttles, such as K4Fe(CN)(4), and O-1(2)-reactive electron shuttles, such as phenol, it is possible to reveal the action mechanism of the supported photosensitizers, while the overall activity can be assessed using hydroquinone. t-Bu4PcAlCl showed significantly lower blank responses and higher specific responses toward chlorophenols compared to t-Bu4PcZn due to the electron-withdrawing effect of the Al3+ metal center. The combination of reactivity insights and the need for only microgram amounts of sensing materials renders the reported system advantageous for practical applications. |
| Address |
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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 |
000855284300001 |
Publication Date |
2022-09-12 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 7.4 |
| Call Number |
UA @ admin @ c:irua:190602 |
Serial |
7190 |
| Permanent link to this record |
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| |
| Author |
Monico, L.; Cotte, M.; Vanmeert, F.; Amidani, L.; Janssens, K.; Nuyts, G.; Garrevoet, J.; Falkenberg, G.; Glatzel, P.; Romani, A.; Miliani, C. |
| Title |
Damages induced by synchrotron radiation-based X-ray microanalysis in chrome yellow paints and related Cr-compounds : assessment, quantification, and mitigation strategies |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
92 |
Issue |
20 |
Pages |
14164-14173 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Synchrotron radiation (SR)-based X-ray methods are powerful analytical tools for several purposes. They are widely used to probe the degradation mechanisms of inorganic artists' pigments in paintings, including chrome yellows (PbCr1-xSxO4; 0 <= x <= 0.8), a class of compounds often found in Van Gogh masterpieces. However, the high intensity and brightness of SR beams raise important issues regarding the potential damage inflicted on the analyzed samples. A thorough knowledge of the SR X-ray sensitivity of each class of pigment in the painting matrix is therefore required to find analytical strategies that seek to minimize the damage for preserving the integrity of the analyzed samples and to avoid data misinterpretation. Here, we employ a combination of Cr K-edge X-ray absorption near-edge structure spectroscopy, Cr-K-beta X-ray emission spectroscopy, and X-ray diffraction to monitor and quantify the effects of SR X-rays on the stability of chrome yellows and related Cr compounds and to define mitigation strategies. We found that the SR X-ray beam exposure induces changes in the oxidation state and local coordination environment of Cr ions and leads to a loss of the compound's crystalline structure. The extent of X-ray damage depends on some intrinsic properties of the samples (chemical composition of the pigment and the presence/absence and nature of the binder). It can be minimized by optimizing the overall fluence/dose released to the samples and by working in vacuum and under cryogenic conditions. |
| 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 |
000584418100072 |
Publication Date |
2020-09-21 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:174363 |
Serial |
7754 |
| Permanent link to this record |
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| |
| Author |
Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K. |
| Title |
Electrochemistry of intact versus degraded cephalosporin antibiotics facilitated by LC–MS analysis |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
93 |
Issue |
4 |
Pages |
2394-2402 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre |
| Abstract |
The electrochemical detection of cephalosporins is a promising approach for the monitoring of cephalosporin levels in process waters. However, this class of antibiotics, like penicillins, is composed of chemically active molecules and susceptible to hydrolysis and aminolysis of the four membered β-lactam ring present. In order to develop a smart monitoring strategy for cephalosporins, the influence of degradation (hydrolysis and aminolysis) on the electrochemical fingerprint has to be taken into account. Therefore, an investigation was carried out to understand the changes of the voltammetric fingerprints upon acidic and alkaline degradation. Changes in fingerprints were correlated to the degradation pathways through the combination of square wave voltammetry and liquid chromatography quadrupole time-of-flight analysis. The characteristic electrochemical signals of the β-lactam ring disappeared upon hydrolysis. Additional oxidation signals that appeared after degradation were elucidated and linked to different degradation products, and therefore, enrich the voltammetric fingerprints with information of the state of the cephalosporins. The applicability of the electrochemical monitoring system was explored by the analysis of the intact and degraded industrial process waters containing the key intermediate 7-aminodeacetoxycephalosporanic acid (7-ADCA). Clearly, the intact process samples exhibited the expected core signals of 7-ADCA and could be quantified, while the degraded samples only showed the newly formed degradation products. |
| 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 |
000618089100063 |
Publication Date |
2021-01-04 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
|
| 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 |
|
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:176206 |
Serial |
7864 |
| Permanent link to this record |
| |
|
| |
| Author |
Wiorek, A.; Parrilla, M.; Cuartero, M.; Crespo, G.A. |
| Title |
Epidermal patch with glucose biosensor : pH and temperature correction toward more accurate sweat analysis during sport practice |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
92 |
Issue |
14 |
Pages |
10153-10161 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
We present an epidermal patch for glucose analysis in sweat incorporating for the first time pH and temperature correction according to local dynamic fluctuations in sweat during on-body tests. This sort of correction is indeed the main novelty of the paper, being crucial toward reliable measurements in every sensor based on an enzymatic element whose activity strongly depends on pH and temperature. The results herein reported for corrected glucose detection during on-body measurements are supported by a two-step validation protocol: with the biosensor operating off- and on-bodily, correlating the results with UV-vis spectrometry and/or ion chromatography. Importantly, the wearable device is a flexible skin patch that comprises a microfluidic cell designed with a sweat collection zone coupled to a fluidic channel in where the needed electrodes are placed: glucose biosensor, pH potentiometric electrode and a temperature sensor. The glucose biosensor presents a linear range of response within the expected physiological levels of glucose in sweat (10-200 mu M), and the calibration parameters are dynamically adjusted to any change in pH and temperature during the sport practice by means of a new “correction approach”. In addition, the sensor displays a fast response time, appropriate selectivity, and excellent reversibility. A total of 9 validated on-body tests are presented: the outcomes revealed a great potential of the wearable glucose sensor toward the provision of reliable physiological data linked to individuals during sport activity. In particular, the developed “correction approach” is expected to impact into the next generation of wearable devices that digitalize physiological activities through chemical information in a trustable manner for both sport and healthcare applications. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000554986200089 |
Publication Date |
2020-06-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:175265 |
Serial |
7931 |
| Permanent link to this record |
| |
|
| |
| Author |
Alvarez-Martin, A.; Newsome, G.A.; Janssens, K. |
| Title |
High-resolution mass spectrometry and nontraditional mass defect analysis of brominated historical pigments |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
93 |
Issue |
44 |
Pages |
14851-14858 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp X-ray Imaging and Spectroscopy (AXIS) |
| Abstract |
The implementation of high-resolution mass spectrometry systems offers new possibilities for the analysis of complex art samples such as historical oil paintings. However, these multicomponent systems generate large and complex data sets that require advanced visualization tools to aid interpretation, especially when no chromatographic separation is performed. In the context of this research, it was crucial to propose a data analysis tool to identify the products generated during the synthesis, drying, and aging of historical pigments. This study reports for the first time a nontraditional mass defect analysis of oil paint samples containing a fugitive brominated-organic pigment, eosin or geranium lake, by using direct infusion electrospray ionization in combination with a high-resolution Orbitrap mass spectrometer. The use of nontraditional Kendrick mass defect plots is presented in this study as a processing and visualization tool to recognize brominated species based on their specific mass defect and isotope pattern. The results demonstrate that this approach could provide valuable molecular compositional information on the degradation pathways of this pigment. We anticipate that mass defect analysis will become highly relevant in future degradation studies of many more historical organic pigments. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000718171600037 |
Publication Date |
2021-10-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| 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 |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:182347 |
Serial |
8038 |
| Permanent link to this record |
| |
|
| |
| Author |
Newsome, G.A.; Kavich, G.; Alvarez-Martin, A. |
| Title |
Interface for reproducible, multishot direct analysis of solid-phase microextraction samples |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
92 |
Issue |
6 |
Pages |
4182-4186 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
An enclosed interface that joins a direct analysis in real time (DART) probe, solid-phase microextraction (SPME) fiber, and the inlet of a high-resolution mass spectrometer is described. Unlike other systems to couple SPME sampling to ambient mass spectrometry, the interface is able to perform discrete analyses on different areas of a single SPME fiber device for up to three technical replicate measurements of one sampling event. Inlet flow speed and desorption temperature are optimized, and reproducibility is demonstrated between replicate analyses on the same derivatized SPME fiber and with sequential fiber sampling events, yielding analyte measurement center of variance (CV) from 3 to 6%. Conditioning is also performed with the enclosed DART. The interface is a straightforward addition to commercially available technologies, and machine diagrams for custom components operated with SPME/DART/MS equipment are included. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000526563900004 |
Publication Date |
2020-02-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:181926 |
Serial |
8113 |
| Permanent link to this record |
| |
|
| |
| Author |
Trashin, S.; Morales-Yánez, F.; Thiruvottriyur Shanmugam, S.; Paredis, L.; Carrión, E.N.; Sariego, I.; Muyldermans, S.; Polman, K.; Gorun, S.M.; De Wael, K. |
| Title |
Nanobody-based immunosensor detection enhanced by photocatalytic-electrochemical redox cycling |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
93 |
Issue |
40 |
Pages |
13606-13614 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
| Abstract |
Detection of antigenic biomarkers present in trace amounts is of crucial importance for medical diagnosis. A parasitic disease, human toxocariasis, lacks an adequate diagnostic method despite its worldwide occurrence. The currently used serology tests may stay positive even years after a possibly unnoticed infection, whereas the direct detection of a re-infection or a still active infection remains a diagnostic challenge due to the low concentration of circulating parasitic antigens. We report a time-efficient sandwich immunosensor using small recombinant single-domain antibodies (nanobodies) derived from camelid heavy-chain antibodies specific to Toxocara canis antigens. An enhanced sensitivity to pg/mL levels is achieved by using a redox cycle consisting of a photocatalytic oxidation and electrochemical reduction steps. The photocatalytic oxidation is achieved by a photosensitizer generating singlet oxygen (1O2) that, in turn, readily reacts with p-nitrophenol enzymatically produced under alkaline conditions. The photooxidation produces benzoquinone that is electrochemically reduced to hydroquinone, generating an amperometric response. The light-driven process could be easily separated from the background, thus making amperometric detection more reliable. The proposed method for detection of the toxocariasis antigen marker shows superior performances compared to other detection schemes with the same nanobodies and outperforms by at least two orders of magnitude the assays based on regular antibodies, thus suggesting new opportunities for electrochemical immunoassays of challenging low levels of antigens. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000708550500025 |
Publication Date |
2021-09-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| 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 |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:181795 |
Serial |
8290 |
| Permanent link to this record |
| |
|
| |
| Author |
Liu, Y.; Cánovas, R.; Crespo, G.A.; Cuartero, M. |
| Title |
Thin-layer potentiometry for creatinine detection in undiluted human urine using ion-exchange membranes as barriers for charged interferences |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
| Volume |
92 |
Issue |
4 |
Pages |
3315-3323 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Herein, thin-layer potentiometry combined with ion-exchange membranes as barriers for charged interferences is demonstrated for the analytical detection of creatinine (CRE) in undiluted human urine. Briefly, CRE diffuses through an anion-exchange membrane (AEM) from a sample contained in one fluidic compartment to a second reservoir, containing the enzyme CRE deiminase. There, CRE reacts with the enzyme, and the formation of ammonium is dynamically monitored by potentiometric ammonium-selective electrodes. This analytical concept is integrated into a lab-on-a-chip microfluidic cell that allows for a high sample throughput and the operation under stop-flow mode, which allows CRE to passively diffuse across the AEM. Conveniently, positively charged species (i.e., potassium, sodium, and ammonium, among others) are repelled by the AEM and never reach the ammonium-selective electrodes; thus, possible interference in the response can be avoided. As a result, the dynamic potential response of the electrodes is entirely ascribed to the stoichiometric formation of ammonium. The new CRE biosensor exhibits a Nernstian slope, within a linear range of response from 1 to 50 mM CRE concentration. As expected, the response time (15–60 min) primarily depends on the CRE diffusion across the AEM. CRE analysis in urine samples displayed excellent results, without requiring sample pretreatment (before the introduction of the sample in the microfluidic chip) and with high compatibility with development into a potential point-of-care clinical tool. In an attempt to decrease the analysis time, the presented analytical methodology for CRE detection is translated into an all-solid-state platform, in which the enzyme is immobilized on the surface of the ammonium-selective electrode and with the AEM on top. While more work is necessary in this direction, the CRE sensor appears to be promising for CRE analysis in both urine and blood. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
|
Publication Date |
2020-01-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
7.4 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
| Call Number |
UA @ admin @ c:irua:184380 |
Serial |
8667 |
| Permanent link to this record |
| |
|
| |
| Author |
Martens, T.; Bogaerts, A.; Brok, W.; van Dijk, J. |
| Title |
Computer simulations of a dielectric barrier discharge used for analytical spectrometry |
Type |
A1 Journal article |
| Year |
2007 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
388 |
Issue |
8 |
Pages |
1583-1594 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Berlin |
Editor |
|
| Language |
|
Wos |
000248373300005 |
Publication Date |
2007-04-18 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642;1618-2650; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
28 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.431; 2007 IF: 2.867 |
| Call Number |
UA @ lucian @ c:irua:65036 |
Serial |
466 |
| Permanent link to this record |
| |
|
| |
| Author |
Jaroszewicz, J.; de Nolf, W.; Janssens, K.; Michalski, A.; Falkenberg, G. |
| Title |
Advantages of combined mu-XRF and mu-XRD for phase characterization of Ti-B-C ceramics compared with conventional X-ray diffraction |
Type |
A1 Journal article |
| Year |
2008 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
391 |
Issue |
4 |
Pages |
1129-1133 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000256088700005 |
Publication Date |
2008-05-05 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
7 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.431; 2008 IF: 3.328 |
| Call Number |
UA @ admin @ c:irua:69317 |
Serial |
5459 |
| Permanent link to this record |
| |
|
| |
| Author |
Cagno, S.; Janssens, K.; Mendera, M. |
| Title |
Compositional analysis of Tuscan glass samples: in search of raw materials fingerprints |
Type |
A1 Journal article |
| Year |
2008 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
391 |
Issue |
4 |
Pages |
1389-1395 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000256088700035 |
Publication Date |
2008-02-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
26 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.431; 2008 IF: 3.328 |
| Call Number |
UA @ admin @ c:irua:69320 |
Serial |
5545 |
| Permanent link to this record |
| |
|
| |
| Author |
Bugani, S.; Camaiti, M.; Morselli, L.; Van de Casteele, E.; Janssens, K. |
| Title |
Investigating morphological changes in treated vs. untreated stone building materials by x-ray micro-CT |
Type |
A1 Journal article |
| Year |
2008 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
391 |
Issue |
4 |
Pages |
1343-1350 |
| Keywords |
A1 Journal article; Vision lab; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000256088700030 |
Publication Date |
2008-03-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
25 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.431; 2008 IF: 3.328 |
| Call Number |
UA @ admin @ c:irua:69319 |
Serial |
5673 |
| Permanent link to this record |
| |
|
| |
| Author |
Terzano, R.; Alfeld, M.; Janssens, K.; Vekemans, B.; Schoonjans, T.; Vincze, L.; Tomasi, N.; Pinton, R.; Cesco, S. |
| Title |
Spatially resolved (semi)quantitative determination of iron (Fe) in plants by means of synchrotron micro X-ray fluorescence |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
405 |
Issue |
10 |
Pages |
3341-3350 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Iron (Fe) is an essential element for plant growth and development; hence determining Fe distribution and concentration inside plant organs at the microscopic level is of great relevance to better understand its metabolism and bioavailability through the food chain. Among the available microanalytical techniques, synchrotron mu-XRF methods can provide a powerful and versatile array of analytical tools to study Fe distribution within plant samples. In the last years, the implementation of new algorithms and detection technologies has opened the way to more accurate (semi)quantitative analyses of complex matrices like plant materials. In this paper, for the first time the distribution of Fe within tomato roots has been imaged and quantified by means of confocal mu-XRF and exploiting a recently developed fundamental parameter-based algorithm. With this approach, Fe concentrations ranging from few hundreds of ppb to several hundreds of ppm can be determined at the microscopic level without cutting sections. Furthermore, Fe (semi)quantitative distribution maps were obtained for the first time by using two opposing detectors to collect simultaneously the XRF radiation emerging from both sides of an intact cucumber leaf. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000316338700033 |
Publication Date |
2013-02-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
27 |
Open Access |
|
| Notes |
; Research was supported by grants from Italian MIUR (FIRB-Programma “Futuro in Ricerca”) and Free University of Bolzano (TN5046 and TN5056). Synchrotron experiments at HASY-LAB were financially supported by the European Community Research Infrastructure Action under the FP6 “Structuring the European Research Area” Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). Matthias Alfeld receives a Ph.D. fellowship of the Research Foundation-Flanders (FWO). We thank Karen Rickers-Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; |
Approved |
Most recent IF: 3.431; 2013 IF: 3.578 |
| Call Number |
UA @ admin @ c:irua:108261 |
Serial |
5838 |
| Permanent link to this record |
| |
|
| |
| Author |
Bugani, S.; Modugno, F.; Lucejko, J.J.; Giachi, G.; Cagno, S.; Cloetens, P.; Janssens, K.; Morselli, L. |
| Title |
Study on the impregnation of archaeological waterlogged wood with consolidation treatments using synchrotron radiation microtomography |
Type |
A1 Journal article |
| Year |
2009 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
395 |
Issue |
7 |
Pages |
1977-1985 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
In favourable conditions of low temperature and low oxygen concentration, archaeological waterlogged wooden artefacts, such as shipwrecks, can survive with a good state of preservation. Nevertheless, anaerobic bacteria can considerably degrade waterlogged wooden objects with a significant loss in polysaccharidic components. Due to these decay processes, wood porosity and water content increase under ageing. In such conditions, the conservation treatments of archaeological wooden artefacts often involve the replacement of water with substances which fill the cavities and help to prevent collapse and stress during drying. The treatments are very often expensive and technically difficult, and their effectiveness very much depends on the chemical and physical characteristics of the substances used for impregnation. Also important are the degree of cavity-filling, penetration depth and distribution in the structure of the wood. In this study, the distribution in wood cavities of some mixtures based on polyethylene glycols and colophony, used for the conservation of waterlogged archaeological wood, was investigated using synchrotron radiation X-ray computed microtomography (SR-A mu CT). This non-destructive imaging technique was useful for the study of the degraded waterlogged wood and enabled us to visualise the morphology of the wood and the distribution of the materials used in the wood treatments. The study has shown how deposition is strictly related to the dimension of the wooden cavities. The work is currently proceeding with the comparison of synchrotron observations with the data of the solutions viscosity and with those of the properties imparted to the wood by the treatments. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000272017000005 |
Publication Date |
2009-09-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
30 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.431; 2009 IF: 3.480 |
| Call Number |
UA @ admin @ c:irua:94493 |
Serial |
5853 |
| Permanent link to this record |
| |
|
| |
| Author |
Bogaerts, A. |
| Title |
Modeling plasmas in analytical chemistry—an example of cross-fertilization |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Analytical And Bioanalytical Chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
412 |
Issue |
24 |
Pages |
6059-6083 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
This paper gives an overview of the modeling work developed in our group in the last 25 years for various plasmas used in analytical spectrochemistry, i.e., glow discharges (GDs), inductively coupled plasmas (ICPs), and laser ablation (LA) for sample introduction in the ICP and for laser-induced breakdown spectroscopy (LIBS). The modeling approaches are briefly presented, which are different for each case, and some characteristic results are illustrated. These plasmas are used not only in analytical chemistry but also in other applications, and the insights obtained in these other fields were quite helpful for us to develop models for the analytical plasmas. Likewise, there is now a huge interest in plasma–liquid interaction, atmospheric pressure glow discharges (APGDs), and dielectric barrier discharges (DBDs) for environmental, medical, and materials applications of plasmas. The insights obtained in these fields are also very relevant for ambient desorption/ionization sources and for liquid sampling, which are nowadays very popular in analytical chemistry, and they could be very helpful in developing models for these sources as well. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000522701700005 |
Publication Date |
2020-03-31 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.3 |
Times cited |
|
Open Access |
|
| Notes |
M. Aghaei, Z. Chen, D. Autrique, T. Martens, and P. Heirman are gratefully acknowledged for their valuable efforts in the model developments illustrated in this paper. |
Approved |
Most recent IF: 4.3; 2020 IF: 3.431 |
| Call Number |
PLASMANT @ plasmant @c:irua:168600 |
Serial |
6412 |
| Permanent link to this record |
| |
|
| |
| Author |
Moro, G.; Barich, H.; Driesen, K.; Montiel, N.F.; Neven, L.; Mendonca, C.D.; Thiruvottriyur Shanmugam, S.; Daems, E.; De Wael, K. |
| Title |
Unlocking the full power of electrochemical fingerprinting for on-site sensing applications |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Analytical And Bioanalytical Chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
|
Issue |
|
Pages |
1-14 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Electrochemical sensing for the semi-quantitative detection of biomarkers, drugs, environmental contaminants, food additives, etc. shows promising results in point-of-care diagnostics and on-site monitoring. More specifically, electrochemical fingerprint (EF)-based sensing strategies are considered an inviting approach for the on-site detection of low molecular weight molecules. The fast growth of electrochemical sensors requires defining the concept of direct electrochemical fingerprinting in sensing. The EF can be defined as the unique electrochemical signal or pattern, mostly recorded by voltammetric techniques, specific for a certain molecule that can be used for its quantitative or semi-quantitative identification in a given analytical context with specified circumstances. The performance of EF-based sensors can be enhanced by considering multiple features of the signal (i.e., oxidation or reduction patterns), in combination with statistical data analysis or sample pretreatments or by including electrode surface modifiers to enrich the EF. In this manuscript, some examples of EF-based sensors, strategies to improve their performances, and open challenges are discussed to unlock the full power of electrochemical fingerprinting for on-site sensing applications. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000523396300002 |
Publication Date |
2020-04-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.3 |
Times cited |
3 |
Open Access |
|
| Notes |
; The presented review is the result of a concerted effort and fruitful discussions among enthusiastic, young, and (for the occasion) female researchers of the AXES research group, each of them with specific expertise and background, under the guidance of the corresponding author. The authors acknowledge FWO-Flanders, BOF-UA, IOF-UA, FAPESP and EU for funding. ; |
Approved |
Most recent IF: 4.3; 2020 IF: 3.431 |
| Call Number |
UA @ admin @ c:irua:168563 |
Serial |
6647 |
| Permanent link to this record |
| |
|
| |
| Author |
Dillen, A.; Vandezande, W.; Daems, D.; Lammertyn, J. |
| Title |
Unraveling the effect of the aptamer complementary element on the performance of duplexed aptamers : a thermodynamic study |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Analytical And Bioanalytical Chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
413 |
Issue |
19 |
Pages |
4739-4750 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Duplexed aptamers (DAs) are widespread aptasensor formats that simultaneously recognize and signal the concentration of target molecules. They are composed of an aptamer and aptamer complementary element (ACE) which consists of a short oligonucleotide that partially inhibits the aptamer sequence. Although the design principles to engineer DAs are straightforward, the tailored development of DAs for a particular target is currently based on trial and error due to limited knowledge of how the ACE sequence affects the final performance of DA biosensors. Therefore, we have established a thermodynamic model describing the influence of the ACE on the performance of DAs applied in equilibrium assays and demonstrated that this relationship can be described by the binding strength between the aptamer and ACE. To validate our theoretical findings, the model was applied to the 29-mer anti-thrombin aptamer as a case study, and an experimental relation between the aptamer-ACE binding strength and performance of DAs was established. The obtained results indicated that our proposed model could accurately describe the effect of the ACE sequence on the performance of the established DAs for thrombin detection, applied for equilibrium assays. Furthermore, to characterize the binding strength between the aptamer and ACEs evaluated in this work, a set of fitting equations was derived which enables thermodynamic characterization of DNA-based interactions through thermal denaturation experiments, thereby overcoming the limitations of current predictive software and chemical denaturation experiments. Altogether, this work encourages the development, characterization, and use of DAs in the field of biosensing. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000659366300001 |
Publication Date |
2021-06-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1618-2642; 1618-2650 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
|
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 3.431 |
| Call Number |
UA @ admin @ c:irua:179163 |
Serial |
8713 |
| Permanent link to this record |
| |
|
| |
| Author |
Salje, E.K.H.; Buckley, A.; Van Tendeloo, G.; Ishibashi, Y.; Nord, G.L. |
| Title |
Needle twins and right-angled twins in minerals: comparison between experiment and theory |
Type |
A1 Journal article |
| Year |
1998 |
Publication |
The American mineralogist |
Abbreviated Journal |
Am Mineral |
| Volume |
83 |
Issue |
|
Pages |
811-822 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000074717900013 |
Publication Date |
0000-00-00 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-004x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.021 |
Times cited |
43 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.021; 1998 IF: 2.124 |
| Call Number |
UA @ lucian @ c:irua:25675 |
Serial |
2288 |
| Permanent link to this record |
| |
|
| |
| Author |
Groat, L.A.; Kek, S.; Bismayer, U.; Schmidt, C.; Krane, H.G.; Meyer, H.; Nistor, L.; Van Tendeloo, G. |
| Title |
A synchrotron radiation, HRTEM, X-ray powder diffraction, and Raman spectroscopic study of malayaite, CaSnSiO5 |
Type |
A1 Journal article |
| Year |
1996 |
Publication |
The American mineralogist |
Abbreviated Journal |
Am Mineral |
| Volume |
81 |
Issue |
5/6 |
Pages |
595-602 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Synchrotron radiation, high-resolution transmission electron microscopy (HRTEM), X-ray powder diffraction, and Raman spectroscopy were used to study the structure and thermal behavior of malayaite, CaSnSiO5. No indications of deviation from A2/a symmetry and no structural transitions were observed between 100 and 870 K. HRTEM revealed that the material is free of domains and antiphase boundaries. However, the lattice constants, cell volume, and Raman-active phonons show a thermal discontinuity near 500 K, which is possibly related to variation of the coordination sphere around the highly anisotropic Ca position. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
A1996UP41100006 |
Publication Date |
0000-00-00 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-004x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.964 |
Times cited |
19 |
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ lucian @ c:irua:16862 |
Serial |
3407 |
| Permanent link to this record |
| |
|
| |
| Author |
Pittarello, L.; Mckibbin, S.; Yamaguchi, A.; Ji, G.; Schryvers, D.; Debaille, V.; Claeys, P. |
| Title |
Two generations of exsolution lamellae in pyroxene from Asuka 09545 : Clues to the thermal evolution of silicates in mesosiderite |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
The American mineralogist |
Abbreviated Journal |
Am Mineral |
| Volume |
104 |
Issue |
11 |
Pages |
1663-1672 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Mesosiderite meteorites consist of a mixture of crustal basaltic or gabbroic material and metal. Their formation process is still debated due to their unexpected combination of crust and core materials, possibly derived from the same planetesimal parent body, and lacking an intervening mantle component. Mesosiderites have experienced an extremely slow cooling rate from ca. 550 degrees C, as recorded in the metal (0.25-0.5 degrees C/Ma). Here we present a detailed investigation of exsolution features in pyroxene from the Antarctic mesosiderite Asuka (A) 09545. Geothermobarometry calculations, lattice parameters, lamellae orientation, and the presence of clinoenstatite as the host were used in an attempt to constrain the evolution of pyroxene from 1150 to 570 degrees C and the formation of two generations of exsolution lamellae. After pigeonite crystallization at ca. 1150 degrees C, the first exsolution process generated the thick augite lamellae along (100) in the temperature interval 1000-900 degrees C. By further cooling, a second order of exsolution lamellae formed within augite along (001), consisting of monoclinic low-Ca pyroxene, equilibrated in the temperature range 900-800 degrees C. The last process, occurring in the 600-500 degrees C temperature range, was likely the inversion of high to low pigeonite in the host crystal, lacking evidence for nucleation of orthopyroxene. The formation of two generations of exsolution lamellae, as well as of likely metastable pigeonite, suggest non-equilibrium conditions. Cooling was sufficiently slow to allow the formation of the lamellae, their preservation, and the transition from high to low pigeonite. In addition, the preservation of such fine-grained lamellae limits long-lasting, impact reheating to a peak temperature lower than 570 degrees C. These features, including the presence of monoclinic low-Ca pyroxene as the host, are reported in only a few mesosiderites. This suggests a possibly different origin and thermal history from most mesosiderites and that the crystallography (i.e., space group) of low-Ca pyroxene could be used as parameter to distinguish mesosiderite populations based on their cooling history. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000494707400014 |
Publication Date |
2019-08-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-004x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.021 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.021 |
| Call Number |
UA @ admin @ c:irua:164645 |
Serial |
6331 |
| Permanent link to this record |
| |
|
| |
| Author |
Matulis, A.; Peeters, F.M. |
| Title |
Analogy between one-dimensional chain models and graphene |
Type |
A1 Journal article |
| Year |
2009 |
Publication |
American journal of physics |
Abbreviated Journal |
Am J Phys |
| Volume |
77 |
Issue |
7 |
Pages |
595-601 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The electron and hole spectrum in single and bilayer graphene is derived from known one-dimensional models, and the relation between the spectrum and symmetry of the lattice is shown. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000266976000003 |
Publication Date |
2009-06-11 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-9505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.069 |
Times cited |
11 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.069; 2009 IF: 0.779 |
| Call Number |
UA @ lucian @ c:irua:77381 |
Serial |
97 |
| Permanent link to this record |
| |
|
| |
| Author |
Ibrahim, I.S.; Peeters, F.M. |
| Title |
The magnetic Kronig-Penney model |
Type |
A1 Journal article |
| Year |
1995 |
Publication |
American journal of physics |
Abbreviated Journal |
Am J Phys |
| Volume |
63 |
Issue |
|
Pages |
171-173 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
A1995QC79100024 |
Publication Date |
2005-03-31 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-9505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
0.956 |
Times cited |
21 |
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ lucian @ c:irua:12200 |
Serial |
1883 |
| Permanent link to this record |
| |
|
| |
| Author |
Fret, J.; Roef, L.; Diels, L.; Tavernier, S.; Vyverman, W.; Michiels, M. |
| Title |
Combining medium recirculation with alternating the microalga production strain : a laboratory and pilot scale cultivation test |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Algal Research-Biomass Biofuels And Bioproducts |
Abbreviated Journal |
Algal Res |
| Volume |
46 |
Issue |
|
Pages |
101763 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Intelligence in PRocesses, Advanced Catalysts and Solvents (iPRACS) |
| Abstract |
Reuse of growth medium after biomass harvesting is a cost-saving approach to improve the economic feasibility of algae mass cultivation. Algal exudates, cell debris and varying amounts of residual nutrients, impose challenges to the recycling of spent medium. In this study, the potential of combining reused medium from different algae species for growing monocultures of other algal strains was evaluated by making use of three successive cultivation setups with increasing volume; 400 mL in turbidostat mode, 2.6 L and 220 L in semi-continuous mode. Cultivation on replenished medium derived from Nannochloropsis sp. and Tisochrysis lutea, had no adverse effect on the productivity of either of the strains, regardless of whether they were grown in their own recycled medium or that of the other alga. Microfiltration of the reused medium proved to be sufficient to avoid cross-contamination. Moreover, a substantial average reduction in water footprint (77%) and nutrient cost (68% or 9 (sic).kg(-1) dry biomass) was achieved. Extension and validation of the medium recycling approach to other economically interesting algae species can contribute to improving the economic feasibility of large scale microalgae production systems. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000512364900013 |
Publication Date |
2020-01-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2211-9264 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
5.1 |
Times cited |
4 |
Open Access |
|
| Notes |
; This work was financially supported by the Agency for Innovation by Science and Technology, Flanders (IWT Baekeland mandatory Jorien Fret, project no. 100678). We thank Kayawe Valentine Mubiana from the Systemic Physiological and Ecotoxicological Research group, University of Antwerp, for the assistance in the analysis of the trace elements. ; |
Approved |
Most recent IF: 5.1; 2020 IF: 3.994 |
| Call Number |
UA @ admin @ c:irua:167742 |
Serial |
6471 |
| Permanent link to this record |
