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Author Heyne, M.H. url  openurl
  Title Chemistry and plasma physics challenges for 2D materials technology Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 167 p.  
  Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Transition-metal dichalcogenides such as MoS2 or WS2 are semiconducting materials with a layered structure. One single layer consists of a plane of metal atoms terminated on the top and bottom by the chalcogen atoms sulfur, selenium, or tellurium. These layers show strong in-plane covalent bonding, whereas the Van-der-Waals bonds in between adjacent layers are weak. Those weak bonds allow the microcleavage and extraction of a monolayer. Transistors built on such monolayer nanosheets are promising due to high electrostatic controllability in comparison to a bulk semiconductor. This is important for fast switching speed and low-power consumption in the OFF-state. Nonetheless, prototypes of such nanosheet transistors show non-idealities due to the fabrication process. Closed films on a large area cannot be obtained by mechanical exfoliation from mm-sized crystals. For wafer-level processing, synthetic growth methods are needed. It is a challenge to obtain a few layer thick crystals with large lateral grains or even without grain boundaries with synthetic growth techniques. This requires pre-conditioned monocrystalline substrates, high-temperature deposition, and polymer-assisted transfer to other target substrates after the growth. Such transfer is a source of cracks in the film and degrades the layers' promising properties by residual polymer from the bond material. Apart from transfer, patterning of the stacked 2D layers is necessary to build devices. The patterning of a 2D material itself or another material on top of it is challenging. The integration of the nanosheets into miniaturized devices cannot be done by conventional continuous-wave dry etching techniques due to the absence of etch stop layers and the vulnerability of these thin layers. To eliminate these issues in growth and integration, we explored the deposition methods on wafer-level and low-damage integration schemes. To this end, we studied the growth of MoS2 by a hybrid physical-chemical vapor deposition for which metal layers were deposited and subsequently sulfurized in H2S to obtain large area 2D layers. The impact of sulfurization temperature, time, partial H2S pressure, and H2 addition on the stoichiometry, crystallinity, and roughness were explored. Furthermore, a selective low-temperature deposition and conversion process at 450 °C for WS2 by the precursors WF6, H2S, and Si was considered. Si was used as a reducing agent for WF6 to deposit thin W films and H2S sulfurized this film in situ. The impact of the reducing agent amount, its surface condition, the temperature window, and the necessary time for the conversion of Si into W and W into WS2 were studied. Further quality improvement strategies on the WS2 were implemented by using extra capping layers in combination with annealing. Capping layers such as Ni and Co for metal-induced crystallization were compared to dielectric capping layers. The impact of the metal capping layer and its thickness on the recrystallization was evaluated. The dielectric capping layer's property to suppress sulfur loss under high temperature was explored. The annealings, which were done by rapid thermal annealing and nanosecond laser annealing, were discussed. Eventually, the fabrication of a heterostack with a MoS2 base layer and selectively grown WS2 was studied. Atomic layer etching was identified as attractive technique to remove the solid precursor Si from MoS2 in a layer-by-layer fashion. The in-situ removal of native SiO2 and the impact towards MoS2 was determined. The created patterned Si on MoS2 was then converted into patterned WS2 on MoS2 by the selective WF6/H2S process developed earlier. This procedure offers an attractive, scalable way to enable the fabrication of 2D devices with CMOS-compatible processes and contributes essential progress in the field 2D materials technology.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:162027 Serial 7662  
Permanent link to this record
 

 
Author Hendriks, E.; Geldof, M.; van den Berg, K.J.; Monico, L.; Miliani, C.; Moretti, P.; Iwanicka, M.; Targowski, P.; Megens, L.; de Groot, S.; van Keulen, H.; Janssens, K.; Vanmeert, F.; van der Snickt, G. doi  isbn
openurl 
  Title Conservation of the Amsterdam sunflowers : from past to future Type H1 Book chapter
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 175-205 T2 - Van Gogh’s Sunflowers illuminated – a  
  Keywords H1 Book chapter; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)  
  Abstract This chapter lays out a conservation timeline, from past to future, for the Amsterdam version of Van Gogh's Sunflowers. It starts by considering the restoration history of the painting in order to assess its current physical state, and looks ahead to formulate an appropriate strategy for future conservation treatment and display. Due attention is paid to the two recorded episodes of restoration performed in 1927 and 1961 by the Dutch restorer, Jan Cornelis Traas. Based on physical and chemical investigation of Sunflowers we attempt to reconstruct what these former treatments (which are barely documented) entailed and consider the repercussions for the present condition of the painting. The former interventions by Traas also serve as a benchmark to reflect on current choices made, highlighting the extent to which ideas and methodologies have continued to evolve over the past century as conservation has moved further away from being a singularly craft-based activity to become an established historical and scientific discipline underpinned by ethical guidelines. Jan Cornelis Traas (1898–1984) As mentioned, the two main recorded interventions to the Amsterdam Sunflowers may be associated with the Dutch restorer, Jan Cornelis Traas, who treated the picture in 1927, close to the start of his career, and again in 1961, shortly before he retired. Traas was the first restorer to be appointed at the Mauritshuis in The Hague where he worked from 1931 to 1962 and treated hundreds of paintings, including iconic masterpieces such as Girl with a Pearl Earring by Johannes Vermeer. Yet despite the magnitude and importance of his restoration oeuvre, J.C. Traas (as he is usually referred to in surviving documents), has remained somewhat obscure. He is shown here in the only known surviving photograph of him at work, shortly before he retired (fig. 7.1). Unlike his illustrious contemporaries, A. Martin de Wild (1899–1969) and Helmut Ruhemann (1891–1973), for example, Traas did not publish anything, he appears to have kept no records of his work and no personal archive is known. However, the study of some newly discovered historical documents, combined with physical examination of Sunflowers and a large number of other works he treated, allows us to recover an idea of his working practices and approaches viewed within the context of his day.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2020-11-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN 978-94-6372-532-3 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:190780 Serial 7727  
Permanent link to this record
 

 
Author van Walsem, J. pdf  openurl
  Title Design and optimization of a photocatalytic reactor for air purification in ventilation systems Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 158 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Photocatalysis has been labeled for decades as a promising technique for air purification. The principle seems straightforward and requires a photocatalyst that is immobilized on a substrate, and one or more UV sources to activate the photocatalyst. No waste products are produced, the reactions occur in mild conditions and the supplies are relatively cheap. Yet it seems that the commercialization of photocatalytic systems does not break through on the global market. The aim of this thesis is to identify and tackle the bottlenecks that impede commercialization from an application-oriented approach. The problem of indoor air pollution is enhanced by the fact that people spend more and more time indoors and that ventilation is kept to a minimum as an energy-saving measure. This inevitably leads to an accumulation of volatile organic compounds (VOCs) that are emitted by e.g. building materials, paint and furniture. Human exposure to VOCs is directly related to the sick building syndrome leading to complaints such as headache, fatigue, dizziness and lack of concentration. In addition, exposure to VOCs is related to serious long-term health effects such as cancer or respiratory diseases. Therefore, significant research efforts are focused on advanced indoor air purification methods. Integration or retrofitting of a photocatalytic (PCO) air purifying unit into heating, ventilation and air conditioning (HVAC) equipment has been chosen as an interesting approach. As a starting point of this thesis, the operational conditions of a ventilation system were mapped. These systems are characterized by high flow rates and the necessity of minimal pressure losses. Pressure losses increase the energy demand and can lead to failure of the ventilation fan and thereby undermine the proper functioning of the ventilation system. A suitable substrate must allow the contaminated air to pass through with a minimal pressure drop, allow sufficient contact time between VOC and photocatalyst, have a large surface area available for coating with excellent adhesion, and be transparent to UV light. Therefore, the permeability and the available exposed surface were selected as main selection criteria. After a thorough quantitative analysis of potential substrates, borosilicate glass tubes were selected. Glass tubes can easily be stacked to constitute a transparent monolithic multi-tube reactor, with their length parallel to the air flow in order to minimize the pressure drop. Moreover, borosilicate glass is relatively inexpensive and has excellent UV-A light transmitting properties. Based on a literature study, a sol-gel coating procedure was selected that is extremely suitable for coating glass substrates. The next step was to optimize the amount of P25 (commercial titanium dioxide) in the photocatalytic sol-gel coating for its application. More P25 in the sol-gel coating results in a higher adsorption capacity and consequently a higher photocatalytic activity, but greatly reduces the transparency of the coating. After an in-depth study, the concentration of 10 g L-1 P25 was selected as the most feasible for multi-tube reactors. Since the operation of photocatalytic reactors is based on a complex interaction of physical and chemical processes, mathematical models were developed, supported by experimental data, that include all these phenomena as a tool for reactor design and optimization. By making use of such models, time-consuming and expensive experimental research can be minimized. However, the experimental validation of models is of utmost importance to prove its reliability and accuracy. Intrinsic kinetic parameters provide the fundamentals for these models as they describe the photocatalytic reaction rate, independent of fluid dynamics, reactor geometry and radiation field. In this work they were estimated by means of a Computational Fluid Dynamics (CFD) study, based on FTIR (Fourier-transform infrared spectroscopy) experiments with a lab scale multi-tube reactor. The kinetic parameters were validated by an alternative analytic approach, emphasizing the accuracy and reliability of the simulations. Finally, the aforementioned CFD approach, based on the simultaneously modelling of airflow, mass transfer, UV light irradiation and photocatalytic reactions, was used to obtain insights for the light source configuration in upscaled multi-tube reactors. After taking all these insights and some practical implications into account, a final upscaled multi-tube reactor design was proposed and converted into a first built prototype. Subsequently, it was evaluated according the CEN-EN-16486-1 standard for VOC removal by the external scientific research center ‘CERTECH’. The scientific results, regarding the mineralization of the VOCs and photocatalytic efficiency of the reactor, demonstrated the feasibility for indoor air purification by the upscaled multi-tube reactor and the possible implementation in ventilation systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:160205 Serial 7763  
Permanent link to this record
 

 
Author Rutten, I.; Safdar, S.; Ven, K.; Daems, D.; Spasic, D.; Lammertyn, J. pdf  openurl
  Title A DNA nanotechnology toolbox for mix-and-match biosensor design Type P3 Proceeding
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords P3 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:166107 Serial 7819  
Permanent link to this record
 

 
Author Vanmeert, F. url  openurl
  Title Highly specific X-ray powder diffraction imaging at the macroscopic and microscopic scale Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract At or below the surface of painted works of art, valuable information is present that provides insights into an object’s past, such as the artist’s technique and the creative process that was followed or its conservation history, but also on its current state of preservation. Typically, a (very) limited set of small paint samples is taken which provide direct access to the individual paint layers. The chemical build-up of these layers can then be investigated in great detail using various microscopic analytical methods. However, in recent years a new trend towards both elemental and chemical imaging techniques has been set which are capable of visualizing the (often) heterogeneous composition of painted objects on a macroscopic scale. In this dissertation, various forms of specificity attainable with X‑ray powder diffraction (XRPD) imaging are explored: at the chemical, material and spatial level. This high specificity is illustrated throughout several applications stemming from the field of cultural heritage, both at the macroscopic (MA) and microscopic (µ) scale. As a first step, XRPD imaging was transformed to a transportable instrument that can be employed for the in situ investigation of artworks, e.g., inside museums and conservation workshops. With this unique instrument large‑scale maps (cm2 – dm2) reflecting the distribution of crystalline phases on/below the surface of flat painted artefacts can be visualized in a noninvasive manner. In this way compound-specific information was attained which can be related to original pigments or materials that have been added in a later stage and even degradation/secondary products that have formed spontaneously inside the paint layers. Additionally, with MA‑XRPD imaging it was possible to link quantitative information of pigment compositions and preferred orientation effects to the 2D compound‑specific distribution images, allowing for a further distinction between very similar artists’ materials. Furthermore, promising results for the limited depth-selectivity of this technique, obtained by exploiting the small shift in the position of the diffraction signals originating from the layered sequence of the pigments, are shown. Finally, a minute paint sample from Wheat stack under a cloudy sky by Van Gogh was investigated at a synchrotron radiation facility with tomographic µ‑XRPD imaging at the microscopic scale. The high chemical and spatial specificity of this imaging method was exploited to further elucidate the degradation pathway of the red lead pigment.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:159805 Serial 8043  
Permanent link to this record
 

 
Author Salvadó, N.; Butí, S.; Pradell, T.; Beltran, V.; Cinque, G.; Juanhuix, J. doi  isbn
openurl 
  Title Identification and distribution of metal soaps and oxalates in oil and tempera paint layers in fifteenth-century altarpieces using synchrotron radiation Techniques Type H1 Book chapter
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 195-210 T2 - Metal soaps in art : conservation and  
  Keywords H1 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The formation and distribution of metal soaps produced as a result of the reactivity and aging of the materials in a fifteenth-century egg tempera and oil paintings on wood are presented. The painting technique involves the application of several paint layers over a ground using, sometimes in the same paint layer sequence, drying oil and egg yolk binders. We show, with a selection of examples, how the use of thin sections and a combination of various micro-sensitive analytical techniques is adequate to obtain the high-quality data necessary for the unambiguous identification of metal soaps and metal oxalates as well as their distribution in the paint layers. The techniques include micro infrared spectroscopy (μSR-FTIR) and micro X-ray diffraction (μSR-XRD) with synchrotron radiation, optical microscopy (OM), and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). The data obtained sheds light about the underlying reaction and aging mechanisms happening in each paint layer and among them. This helps to define the state of conservation of the artworks.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2019-03-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN 978-3-319-90616-4; 2366-6226; 978-3-319-90617-1 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:172891 Serial 8051  
Permanent link to this record
 

 
Author Hellemans, K. url  openurl
  Title Laser ablation ICP-MS as a tool for surface analysis in comparison to other elemental analysis methods Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 229 p.  
  Keywords Doctoral thesis; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Dit onderzoek presenteert een overzicht van de mogelijkheden van LA-ICP-MS als een techniek voor kwantitatieve analyse, bepalen van isotoopverhoudingen en elementaire beeldvorming. Hiervoor wordt de techniek zelf voorgesteld en worden de belangrijkste parameters die een invloed hebben op de kwaliteit van een LA-ICP-MS meting beschreven. Voor kwantitieve analyse worden de huidige calibratiestrategieën voor LA-ICP-MS toegelicht, zowel op het vlak van selectie en bereiding van standaarden als op het vlak van dataverwerking. Daarnaast werd een nieuwe calibratiestrategie voorgesteld, gebaseerd op een lineaire combinatie van standaarden. Een case study met de traditionele calibratiestrategie uit de literatuur werd uitgevoerd en vergeleken met data van SEM-EDX om een referentiekader te schetsen voor de performantie van de techniek. In een tweede case study werd onze nieuwe calibratiestrategie toegepast en werd er uitsluitend gebruik gemaakt van LA-ICP-MS, wat uitstekende resultaten opleverde. Met het oog op het bepalen van isotoopverhoudingen, werd er onderzocht wat de limieten zijn van het gebruik van een lage resolutie quadrupool massaspectrometer voor deze bepaling. Dit stelde ons in staat om de te verwachten accuraatheid en precisie in te schatten. De performantie bleek goed genoeg te zijn om weapon-grade plutonium te onderscheiden van global fall-out, zoals het werd aangetoond in de case study omtrent dit onderwerp. Uiteindelijk hebben we ook LA-ICP-MS geëvalueerd als een techniek voor elementaire beeldvorming, waarbij we tevens de meest courante multivariate data analyse hebben beschreven. Om de techniek te plaatsen tegenover andere elementaire technieken, werd een historisch verffragment geanalyseerd dat in het verleden reeds geanalyseerd was met SEM-EDX and μ-XRD. Op die manier konden we de resultaten accuraat vergelijken met de andere technieken.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:160063 Serial 8152  
Permanent link to this record
 

 
Author Geldof, M.; Monico, L.; Johnson, D.H.; Miliani, C.; Romani, A.; Grazia, C.; Buti, D.; Brunetti, B.G.; Janssens, K.; Van der Snickt, G.; Vanmeert, F. doi  isbn
openurl 
  Title Methods and materials of the Amsterdam sunflowers Type H1 Book chapter
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 85-123 T2 - Van Gogh’s Sunflowers illuminated – ar  
  Keywords H1 Book chapter; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)  
  Abstract This chapter explains the materials and techniques employed in the Amsterdam Sunflowers, enabling a comparison with the London version described in chapter 3. Building upon the 2016 article published in the National Gallery Technical Bulletin, it incorporates the latest findings gained by computer-assisted methods used to characterize the canvas support, as well as in-situ campaigns of non-invasive investigation together with further analysis of microscopic paint samples. The chapter sequence follows the steps in Van Gogh's working practice. Starting with the canvas, automated analysis of the weave enables the provenance of the canvas to be traced back to a particular roll of linen ordered by Van Gogh. Combining technical evidence with knowledge of historical manufacturing techniques further allows us to reconstruct the way in which Van Gogh divided his canvas roll into pieces used for Sunflowers and other paintings. We go on to consider how, with the original painting at hand, he used charcoal to transfer the motif of the London Sunflowers onto his blank canvas. Despite careful planning of the composition, an adjustment was required late in the working process, when Van Gogh added a painted wooden strip to extend the background above the flower at the top edge of the canvas. The artist's process of working up the composition in paint is described, paying special attention to his use of colour. The pigments and pigment mixtures used in the Amsterdam Sunflowers have been comprehensively mapped and are compared with the London picture, with discussion of some similarities and differences that account for the distinctive colour scheme of each painting. This understanding of colour application in the Amsterdam Sunflowers lays the foundation for subsequent chapters that will go on to consider the impact of light-induced colour changes that have taken place over time, and the related need to define appropriate lighting guidelines for the future safe preservation of this painting and others made with similar materials (chapters 5 and 7).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2020-11-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN 978-94-6372-532-3 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:190781 Serial 8223  
Permanent link to this record
 

 
Author Muys, M. openurl 
  Title Microbial protein as sustainable feed and food ingredient : production and nutritional quality of phototrophs and aerobic heterotrophs Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 262 p.  
  Keywords Doctoral thesis; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract In iets meer dan 30 jaar moeten we tot 50% meer eiwit produceren, terwijl onze conventionele lineaire voedselproductieketen reeds de grenzen van duurzaamheid overschrijdt. Microbieel eiwit (MP), de eiwitrijke biomassa van micro-organismen, werd onderzocht als nieuw voeder en voedselingrediënt in een circulaire eiwitproductieketen. MP-productie kan gebaseerd zijn op primaire grondstoffen om zo de inefficiënte stappen in de huidige eiwitproductie over te slaan, of de productie kan gebaseerd zijn op secundaire grondstoffen afkomstig van de verliezen in de conventionele productieketen (bijvoorbeeld afvalwater). Zowel indirecte als directe strategiën voor nutriëntenherwinning kunnen geïdentificeerd worden. Indirecte nutriëntenherwinning werd onderzocht door struviet toe te passen als fosfor- en stikstofbron voor MP-productie. Struviet, een herwinningsproduct in de afvalwaterzuivering, bleek een hoge zuiverheidsgraad te hebben waardoor het een uitstekende selectieve barrière vormt tussen afvalstroom en MP productie. Oplossingssnelheden en MP groei-experimenten toonden aan dat struviet gemakkelijk gedoseerd kan worden in functie van de microbiële nutriëntenbehoeftes, waarnaast problemen vermeden worden gerelateerd aan de turbiditeit van nevenstromen, wat de productie van fototrofe MP mogelijk maakt. Daarnaast werd ook directe nutriëntenherwinning onderzocht. Hierbij werden de voedingswaarde en veiligheid geanalyseerd van biomassa bestaande uit aerobe heterotrofe bacteriën (AHB) afkomstig van effluentzuivering van 25 bedrijven in de voedings- en drankensector. Verder werd ook de temporele variabiliteit in kaart gebracht. Er werd een veelbelovend eiwitgehalte geobserveerd waarvan de variabiliteit aanzienlijke was. Verder werd aangetoond dat het eiwitgehalte positief gecorreleerd was met stikstofbelasting en negatief met slibverblijftijd, wat een indicatie is dat de implementatie van een geoptimaliseerd productieproces, de biomassakwaliteit gevoelig kan verhogen. Bovendien was de veiligheid als veevoeder gegarandeerd op vlak van de meeste contaminanten. In het daarop volgende hoofdstuk werd de variabiliteit in voedingswaarde en veiligheid bestudeerd van commerciële fototrofe MP (de microalgen Chlorella en Spirulina), gekweekt op primaire grondstoffen. De waargenomen variabiliteit in voedingswaarde vereist verdere optimalisatie van het productieproces. Er werd ook waargenomen dat een hoog eiwitgehalte geen hoge totale voedingswaarde impliceert, omdat de verteerbaarheid en de eiwitkwaliteit nog steeds ongunstig kunnen zijn. Op basis van gemeten contaminanten geeft een veilige consumptiedosis aan dat microalgen perfect kunnen worden geconsumeerd als volwaardige eiwitbron in plaats van als supplement, hun huidige hoofdtoepassing. In een laatste experimenteel hoofdstuk werd onderzocht hoe de variabiliteit in biomassakwaliteit van microalgen kan worden gereduceerd en hoe een stabiele, hoogwaardige biomassaproductie kan worden bekomen. De invloed van oogsttijd, operationele modus en fotoperiode werd bepaald op de productiviteit van biomassa, eiwit en essentiële aminozuren en er werden optimale productieparameters geïdentificeerd. Samengevat is MP-productie op basis van indirecte en directe nutriëntenherwinning veelbelovend. Verdere technologische ontwikkelingen en het verhogen van bewustwording en sociale acceptatie, moeten een verdere introductie van MP in de voeder- en voedingsmarkt faciliteren. Hier kan MP een belangrijke oplossing vertegenwoordigen om de exponentieel groeiende wereldbevolking op een duurzame manier te voeden.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:160717 Serial 8244  
Permanent link to this record
 

 
Author Peeters, B.; Safdar, S.; Carlier, B.; Spasic, D.; Daems, D.; Lammertyn, J. pdf  openurl
  Title PCR amplified DNAzyme-amplicons for generic solid-phase antimicrobial resistance screening Type P1 Proceeding
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 971-974 T2 - Transducers 2019 : Eurosensors XXXIII  
  Keywords P1 Proceeding; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Fiber optic surface plasmon resonance (FO-SPR) has shown its potential for the detection of nucleic acids and more recently the technology has been combined with catalytic active strands such as DNAzymes. In this work, an innovative, generic solid-phase DNA sensor concept is presented, based on FO-SPR and PCR amplified DNAzyme activity. Improved levels of specificity and sensitivity were obtained down to picomolar concentrations. Moreover, the FO-SPR sensor concept enables AuNP amplified DNA target detection, independent of the target sequence length. The FO-SPR sensor was demonstrated for the screening of the mobile colistin resistance (MCR-2) gene, a gene important for the antimicrobial resistance in Gram-negative species such as E. Coli.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000539487000245 Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:166108 Serial 8367  
Permanent link to this record
 

 
Author Blommaerts, N. url  openurl
  Title Plasmonic core shell nanoparticles : from synthesis to photocatalytic applications Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 153 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Het gebruik van plasmon-actieve nanodeeltjes heeft de laatste 10 jaar zeer veel interesse gewekt bij onderzoekers in verschillende toepassingsdomeinen zoals fotokatalyse of oppervlakte versterkte Raman spectroscopie. Er is echter een grote limiterende factor bij het gebruik van edelmetaal nanodeeltjes zoals goud en zilver en dat is de stabiliteit. Deze oxideren en aggregeren snel, zeker in oxidatieve omgeving zoals in lucht. Een interessante aanpak om plasmon-actieve nanodeeltjes te stabiliseren, is om ze te omgeven in een schil, met andere woorden om een kern-schil nanodeeltje te vormen. Er zijn een heel aantal verschillende manieren waarop kern-schil nanodeeltjes gesynthetiseerd kunnen worden. In eerste instantie werden metaal nanodeeltjes omgeven door een (dunne) TiO2 laag. Afhankelijk van de hoeveelheid TiO2 precursor kon de dikte van de laag gecontroleerd worden tot enkele nanometers dik. De stalen werden getest voor de fotokatalytische afbraak van een vaste laag stearinezuur waarbij toevoeging van 2 wt% metaal@TiO2 op P25 leidde tot een significante verbetering in afbraakefficiëntie in vergelijking met zuiver P25. Een andere manier voor het stabiliseren van metaal nanodeeltjes is door ze te omgeven met een polymeerschil. Op deze manier kon de laagdikte gecontroleerd worden met sub-nanometer controle wat een zeer belangrijke factor is voor de hoeveelheid near-field versterking dat buiten de polymeer schil kan gaan. Een XTT test werd uitgevoerd om te bepalen wat de zuurstofactivatie snelheid was van goud en zilver (en goud-zilver bimetallische) nanodeeltjes, al dan niet omgeven door een (niet-)geleidende polymeer laag. Wanneer de stalen gecoat werden met vier niet-geleidende polymeerlagen zakte de zuurstofactivatie nagenoeg tot nul. Aan de andere kant, als goud nanodeeltjes werden omgeven door een geleidende schil was er nog steeds zuurstofactivatie, hoewel lager dan in het geval van goud zonder laag. Het laatste deel van deze thesis focuste meer op mogelijke toepassingen in luchtzuivering. In dit werk werd een glazen buis, gecoat aan de binnenkant met (Ag@polymer gemodificeerd) TiO2, als een spiraal rond een UVA lamp gewikkeld. De geoptimaliseerde spiraalreactor werd dan vergeleken met een conventionele cilindervormige fotoreactor, met dezelfde dimensies en totale katalysatorbelading, over een grote range aan experimentele condities. Uit de resultaten bleek dat de spiraalreactor significant betere afbraakefficiënties vertoonde in vergelijking met de conventionele cilindervormige reactor over een grote range aan debieten. Een adsorptiestap in combinatie met de geoptimaliseerde spiraalreactor zou kunnen leiden tot een zeer krachtige luchtzuiveringstechnologie.  
  Address  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:164835 Serial 8389  
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Author Sui, Y. url  isbn
openurl 
  Title Producing nutritional protein with Dunaliella microalgae : technological and economic optimization Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 140 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract ​In this thesis, microalga Dunaliella salina is highlighted as a novel source of protein to sustain the human needs. As demonstrated in this thesis, the biochemical composition of D. salina is not fixed, and can be substantially influenced by internal and external conditions. In order to comply with the human requirement of protein, various important factors affecting the protein quantity and quality of D. salina have been evaluated in this thesis for an optimized production strategy. All tested parameters, namely salinity, pH, light regimes (continuous light and light/dark cycle), light intensity, nutrient levels and growth phases can contribute to significant variations of protein content and essential amino acid (EAA) level in D. salina. Ultimately, D. salina is capable of producing high amount of superior quality protein, complying with the FAO reference for human consumption. Even better, such protein of superior quality can be accompanied by unique β-carotene accumulation in D. salina, a pigment with anti-oxidant pro-vitamin A effect. In the end, according to the techno-economic analysis (TEA), it is economically feasible to produce D. salina biomass for human nutrition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN 978-90-5728-630-8 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:164002 Serial 8420  
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Author Alloul, A. isbn  openurl
  Title Purple bacteria as microbial protein source : technology development, community control, economic optimization and biomass valorization Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 212 p.  
  Keywords Doctoral thesis; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract ​Food production is a cornerstone in contemporary industrial societies. Its production requires land, water and enormous amounts of fertilizers. These precious fertilizers enter the linear food chain and suffer from a cascade of inefficiencies, resulting in detrimental effects to the environment. A radical transforming of the current food production chain is, therefore, essential to guarantee a sustainable future for humanity. ​This thesis has studied the production of microbial protein (i.e. single-cell protein), which is the use of microorganisms such as yeast, fungi, algae and bacteria as protein ingredient for animal feed. The type of microorganisms targeted in this thesis were purple non-sulfur bacteria (PNSB). These bacteria are an extremely heterogenic group that contain photosynthetic pigments and are able to perform anoxygenic photosynthesis. The core focus of the thesis was technology development for the production of PNSB as a source of microbial protein on wastewater and fresh fertilizers. In the final stage of this research, it was the objective to explore the potential of PNSB as a nutritious feed ingredient for shrimp. ​Overall, this work has provided the building blocks to transform the conventional food production chain. The findings show that PNSB production and biomass valorization is within reach. Further pilot implementation and cost reduction will facilitate the introduction of PNSB production in future’s wastewater treatment plants and the valorization of the biomass as nutritious animal feed ingredient.​  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN 978-90-5728-636-0 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:164820 Serial 8430  
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Author Tavkhelidze, I.; Gielis, J. openurl 
  Title Structure of the dm knives and process of cutting of GML(man) or GRT(man) bodies Type A3 Journal article
  Year 2019 Publication Sn – 1512-0066 Abbreviated Journal  
  Volume 33 Issue Pages  
  Keywords A3 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:164897 Serial 8588  
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Author Ghasemitarei, M. url  openurl
  Title Study of the interaction of plasma radicals with malignant tumor cells by means of Molecular Dynamics simulation Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 117 p.  
  Keywords Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract abstract not available  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:164763 Serial 8606  
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Author Taghizadeh Sisakht, E. file  openurl
  Title Tight-binding investigation of the electronic properties of phosphorene and phosphorene nanoribbons Type Doctoral thesis
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 150 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract abstract not available  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:166195 Serial 8670  
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Author Vanmeert, F.; Van der Snickt, G.; Legrand, S.; Janssens, K. isbn  openurl
  Title Velázquez? A portrait of Pope Innocent X : an X-ray imaging investigation (II) Type H3 Book chapter
  Year 2019 Publication Abbreviated Journal  
  Volume Issue Pages 132-141 T2 - Velázquez : Anregungen, Vorschläge, L  
  Keywords H3 Book chapter; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Encompassing a broad spectrum of methodological approaches and aims, the scholars contributing to this volume offer renewed perspectives on the multifaceted oeuvre of Diego Velázquez. The seventeenth-century artist’s exceptional religious works as well as his numerous portraits are examined within the social and historical context of Velázquez’s milieu which included both the Spanish court as well as circles comprising important intellectual figures of his time. Following a close investigation of his works, which also includes the results of recent technological examinations on his paintings, the contributors to this volume offer new, exciting findings and discussions on the inspirations, sources and possible intentions of Velázquez.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN 978-3-99020-155-8 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:190783 Serial 8736  
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Author Daems, N.; De Mot, B.; Choukroun, D.; Van Daele, K.; Li, C.; Hubin, A.; Bals, S.; Hereijgers, J.; Breugelmans, T. url  doi
openurl 
  Title Nickel-containing N-doped carbon as effective electrocatalysts for the reduction of CO2 to CO in a continuous-flow electrolyzer Type A1 Journal article
  Year 2019 Publication Sustainable energy & fuels Abbreviated Journal  
  Volume 4 Issue 4 Pages 1296-1311  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)  
  Abstract Nickel-containing N-doped carbons were synthesized for the electrochemical reduction of CO2 to CO, which is a promising approach to reduce the atmospheric CO2 levels and its negative impact on the environment. Unfortunately, poor performance (activity, selectivity and/or stability) is still a major hurdle for the economical implementation of this type of materials. The electrocatalysts were prepared through an easily up-scalable and easily tunable method based on the pyrolysis of Ni-containing N-doped carbons. Ni–N–AC–B1 synthesized with a high relative amount of nitrogen and nickel with respect to carbon, was identified as the most promising candidate for this reaction based on its partial CO current density (4.2 mA cm−2), its overpotential (0.57 V) and its faradaic efficiency to CO (>99%). This results in unprecedented values for the current density per g active sites (690 A g−1 active sites). Combined with its decent stability and its high performance in an actual electrolyzer setup, this makes it a promising candidate for the electrochemical reduction of CO2 to CO on a larger scale. Finally, the evaluation of this kind of material in a flow-cell setup has been limited and to the best of our knowledge never included an evaluation of several crucial parameters (e.g. electrolyte type, anode composition and membrane type) and is an essential investigation in the move towards up-scaling and ultimately industrial application of this technique. This study resulted in an optimal cell configuration, consisting of Pt as an anode, Fumatech® as the membrane and 1 M KHCO3 and 2 M KOH as catholyte and anolyte, respectively. In conclusion, this research offers a unique combination of electrocatalyst development and reactor optimization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000518690900030 Publication Date 2019-12-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 14 Open Access OpenAccess  
  Notes ; The authors acknowledge sponsoring from the research foundation of Flanders (FWO) in the frame of a post-doctoral grant (12Y3919N – ND). J. Hereijgers was supported through a postdoctoral fellowship (28761) of the Research Foundation Flanders (FWO). This project was co-funded by the Interreg 2 Seas-Program 2014-2020, co-.nanced by the European Fund for Regional Development in the frame of subsidiary contract nr 2S03-019. This work was further performed in the framework of the Catalisti cluster SBO project CO2PERATE (“All renewable CCU based on formic acid integrated in an industrial microgrid”), with the.nancial support of VLAIO (Flemish Agency for Innovation and Entrepreneurship). This project.nally received funding from the European Research Council (ERC Consolidator Grant 815128, REALNANO). We thank Karen Leyssens for helping with the N<INF>2</INF> physisorption measurements and Kitty Baert (VUB) for analyzing the samples with XPS and Raman. ; sygma Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:165482 Serial 6311  
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Author Kulkarni, S.; Gonzalez-Quiroga, A.; Nuñez, M.; Schuerewegen, C.; Perreault, P.; Goel, C.; Heynderickx, G.J.; Van Geem, K.M.; Marin, G.B. pdf  doi
openurl 
  Title An experimental and numerical study of the suppression of jets, counterflow, and backflow in vortex units Type A1 Journal article
  Year 2019 Publication AIChE journal Abbreviated Journal  
  Volume 65 Issue 8 Pages e16614-13  
  Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract Vortex units are commonly considered for various single and multiphase applications due to their process intensification capabilities. The transition from gas‐only flow to gas–solid flow remains largely unexplored nonetheless. During this transition, primary flow phenomenon, jets, and secondary flow phenomena, counterflow and backflow, are substantially reduced, before a rotating solids bed is established. This transitional flow regime is referred to as the vortex suppression regime. In the present work, this flow transition is identified and validated through experimental and computational studies in two vortex units with a scale differing by a factor of 2, using spherical aluminum and alumina particles. This experimental data supports the proposed theoretical particle monolayer solids loading that allows estimation of vortex suppression regime solids capacity for any vortex unit. It is shown that the vortex suppression regime is established at a solids loading theoretically corresponding to a monolayer being formed in the unit for 1g‐Geldart D‐ and 1g‐Geldart B‐type particles. The model closely agrees with experimental vortex suppression range for both aluminum and alumina particles. The model, as well as the experimental data, shows that the flow suppression regime depends on unit dimensions, particle diameter, and particle density but is independent of gas flow rate. This combined study, based on experimental and computational data and on a theoretical model, reveals the vortex suppression to be one of the basic operational parameters to study flow in a vortex unit and that a simple monolayer model allows to estimate the needed solids loading for any vortex device to induce this flow transition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000474620800026 Publication Date 2019-04-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0001-1541 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:162121 Serial 7945  
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Author Pittarello, L.; Mckibbin, S.; Yamaguchi, A.; Ji, G.; Schryvers, D.; Debaille, V.; Claeys, P. pdf  doi
openurl 
  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 (up) 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  
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Author Florea, A.; Cowen, T.; Piletsky, S.; De Wael, K. url  doi
openurl 
  Title Electrochemical analysis of cocaine in real samples based on electrodeposited biomimetic affinity ligands Type A1 Journal article
  Year 2019 Publication The analyst Abbreviated Journal Analyst  
  Volume 144 Issue 15 Pages 4639-4646  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract A selective electrochemical sensor for direct detection of cocaine was developed based on molecularly imprinted polymers electropolymerized onto graphene-modified electrodes. Palladium nanoparticles were integrated in the sensing layer for the benefit of enhancing the communication between imprinted sites and electrode and improving their homogenous distribution. The molecularly imprinted polymer was synthesized by cyclic voltammetry using p-aminobenzoic acid as high affinity monomer selected by computational modeling, and cocaine as template molecule. Experimental parameters related to the electrochemical deposition of palladium nanoparticles, pH, composition of electropolymerization mixture, extraction and rebinding condition were studied and optimized. Under optimized conditions the oxidation peak current varied linearly with cocaine concentration in the range of 100-500 µM, with a detection limit of 50 µM (RSD 0.71%, n=3). The molecularly imprinted sensor was able to detect cocaine in saliva and river water with good recoveries after sample pretreatment and was successfully applied for screening real street samples for cocaine.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000476812000021 Publication Date 2019-06-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2654 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.885 Times cited 3 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. ; Approved Most recent IF: 3.885  
  Call Number UA @ admin @ c:irua:160062 Serial 5586  
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Author Sleegers, N.; van Nuijs, A.L.N.; van den Berg, M.; De Wael, K. url  doi
openurl 
  Title Cephalosporin antibiotics : electrochemical fingerprints and core structure reactions investigated by LC-MSMS Type A1 Journal article
  Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 91 Issue 3 Pages 2035-2041  
  Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre  
  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.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000458220300055 Publication Date 2019-01-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 6 Open Access  
  Notes ; The authors acknowledge financial support from the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; Approved Most recent IF: 6.32  
  Call Number UA @ admin @ c:irua:156046 Serial 5497  
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Author Florea, A.; Schram, J.; De Jong, M.; Eliaerts, J.; Van Durme, F.; Kaur, B.; Samyn, N.; De Wael, K. url  doi
openurl 
  Title Electrochemical strategies for adulterated heroin samples Type A1 Journal article
  Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 91 Issue 12 Pages 7920-7928  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Electrochemical strategies to selectively detect heroin in street samples without the use of complicated electrode modifications were developed for the first time. For this purpose, heroin, mixing agents (adulterants, cutting agent, and impurities), and their binary mixtures were subjected to square wave voltammetry measurements at bare graphite electrodes at pH 7.0 and pH 12.0, in order to elucidate the unique electrochemical fingerprint of heroin and mixing agents as well as possible interferences or reciprocal influences. Adjusting the pH from pH 7.0 to pH 12.0 allowed a more accurate detection of heroin in the presence of most common mixing agents. Furthermore, the benefit of introducing a preconditioning step prior to running square wave voltammetry on the electrochemical fingerprint enrichment was explored. Mixtures of heroin with other drugs (cocaine, 3,4-methylenedioxymethamphetamine, and morphine) were also tested to explore the possibility of their discrimination and simultaneous detection. The feasibility of the proposed electrochemical strategies was tested on realistic heroin street samples from forensic cases, showing promising results for fast, on-site detection tools of drugs of abuse.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000472682000056 Publication Date 2019-05-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 2 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. The authors also acknowledge IOF (UAntwerp) and Belspo for financial support. ; Approved Most recent IF: 6.32  
  Call Number UA @ admin @ c:irua:160061 Serial 5596  
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Author Morales-Yanez, F.; Trashin, S.; Hermy, M.; Sariego, I.; Polman, K.; Muyldermans, S.; De Wael, K. url  doi
openurl 
  Title Fast one-step ultrasensitive detection of toxocara canis antigens by a nanobody-based electrochemical magnetosensor Type A1 Journal article
  Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 91 Issue 18 Pages 11582-11588  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Human toxocariasis (HT) is a cosmopolitan zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis. Current HT diagnostic methods do not discriminate between active and past infections. Here, we present a method to quantify Toxocara excretory/secretory antigen, aiming to identify active cases of HT. High specificity is achieved by employing nanobodies (Nbs), single domain antigen binding fragments from camelid heavy chain-only antibodies. High sensitivity is obtained by the design of an electrochemical magnetosensor with an amperometric read-out. Reliable detection of TES antigen at 10 and 30 pg/mL level was demonstrated in phosphate buffered saline and serum, respectively. Moreover, the assay showed no cross-reactivity with other nematode antigens. To our knowledge, this is the most sensitive method to quantify the TES antigen so far. It also has great potential to develop point of care diagnostic systems in other conditions where high sensitivity and specificity are required.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000487156900016 Publication Date 2019-08-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 2 Open Access  
  Notes ; This project was funded by the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO-Flanders, Project G.0189.13N) and BOF UAntwerp. The authors acknowledge Prof. Pierre Dorny (Institute of Tropical Medicine Antwerp) and Dr. Beatrice Nickel (Swiss Institute of Tropical Medicine) for providing the antigens needed for the cross-reactivity experiments. ; Approved Most recent IF: 6.32  
  Call Number UA @ admin @ c:irua:163784 Serial 5621  
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Author Neven, L.; Thiruvottriyur Shanmugam, S.; Rahemi, V.; Trashin, S.; Sleegers, N.; Carrion, E.N.; Gorun, S.M.; De Wael, K. pdf  url
doi  openurl
  Title Optimized photoelectrochemical detection of essential drugs bearing phenolic groups Type A1 Journal article
  Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 91 Issue 15 Pages 9962-9969  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The World Health Organization (WHO) model “List of Essential Medicines” includes among indispensable medicines antibacterials and pain and migraine relievers. Monitoring their concentration in the environment, while challenging, is important in the context of antibiotic resistance as well as their production of highly toxic compounds via hydrolysis. Traditional detection methods such as high-performance liquid chromatography (HPLC) or LC combined with tandem mass spectrometry or UV-vis spectroscopy are time-consuming, have a high cost, require skilled operators and are difficult to adapt for field operations. In contrast, (electrochemical) sensors have elicited interest because of their rapid response, high selectivity, and sensitivity as well as potential for on-site detection. Previously, we reported a novel sensor system based on a type II photosensitizer, which combines the advantages of enzymatic sensors (high sensitivity) and photoelectrochemical sensors (easy baseline subtraction). Under red-light illumination, the photosensitizer produces singlet oxygen which oxidizes phenolic compounds present in the sample. The subsequent reduction of the oxidized phenolic compounds at the electrode surface gives rise to a quantifiable photocurrent and leads to the generation of a redox cycle. Herein we report the optimization in terms of pH and applied potential of the photoelectrochemical detection of the hydrolysis product of paracetamol, i.e., 4-aminophenol (4-AP), and two antibacterials, namely, cefadroxil (CFD, beta-lactam antibiotic) and doxycycline (DXC, tetracycline antibiotic). The optimized conditions resulted in a detection limit of 0.2 mu mol L-1 for DXC, but in a 10 times higher sensitivity, 20 nmol L-1, for CFD. An even higher sensitivity, 7 nmol L-1, was noted for 4-AP.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000480499200086 Publication Date 2019-06-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 2 Open Access  
  Notes ; FWO and UA-BOF are acknowledged for financial support. The Center for Functional Materials of Seton Hall University is thanked for support (S.M.G. and E.N.C.). Joren Van Loon is thanked for the graphical abstract. This research was supported by the medium scale research infrastructure funding Hercules funding (SEM). ; Approved Most recent IF: 6.32  
  Call Number UA @ admin @ c:irua:161831 Serial 5763  
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Author Alvarez-Martin, A.; Cleland, T.P.; Kavich, G.M.; Janssens, K.; Newsome, G.A. pdf  doi
openurl 
  Title Rapid evaluation of the debromination mechanism of eosin in oil paint by direct analysis in real time and direct infusion-electrospray ionization mass spectrometry Type A1 Journal article
  Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 91 Issue 16 Pages 10856-10863  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract Eosin is a synthetic organic colorant prone to fading under the influence of light. On the basis of the growing interest in the understanding of the discoloration mechanism of eosin-based lakes, this study compares the ability of two ultrafast and ultrasensitive mass spectrometry techniques to detect eosin derivatives in complex matrices, such as oil media without the use of conventional separation columns or additional sample preparation protocols. Direct analysis in real time mass spectrometry (DART-MS) and direct infusion electrospray ionization mass spectrometry (DI-ESI-MS) were used to characterize the degradation pathway of eosin in oil media. The analysis protocols developed in this study are applied to discern the degradation mechanism of the lake pigment eosin (comprising the molecule per se complexed to an inorganic substrate) dispersed in linseed oil to create an oil paint. The analysis of oil paints by high resolution MS without an extraction methodology that modifies the system chemistry allowed us to identify the degradation forms without causing any additional fragmentation. Both techniques revealed the primary photodegradation pathway of eosin in linseed oil, and DI-ESI-MS provided additional information on the native conformation of the lake.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000482545300069 Publication Date 2019-07-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 3 Open Access  
  Notes ; The authors would like to acknowledge the SolarPaint project (GOA program, Antwerp University Research Council) and Smithsonian Institution for financial support. ; Approved Most recent IF: 6.32  
  Call Number UA @ admin @ c:irua:162879 Serial 5800  
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Author Vanmeert, F.; De Keyser, N.; van Loon, A.; Klaassen, L.; Noble, P.; Janssens, K. url  doi
openurl 
  Title Transmission and reflection mode macroscopic x-ray powder diffraction imaging for the noninvasive visualization of paint degradation in still life paintings by Jan Davidsz. de Heem Type A1 Journal article
  Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 91 Issue 11 Pages 7153-7161  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)  
  Abstract The use of noninvasive chemical imaging techniques is becoming more widespread for the study of cultural heritage artifacts. Recently a mobile instrument for macroscopic X-ray powder diffraction (MA-XRPD) scanning was developed, which is capable of visualizing the distribution of crystalline (pigment) phases in quasi-flat-painted artifacts. In this study, MA-XRPD is used in both transmission and reflection mode for the analysis of three 17th century still life paintings, two paintings by Jan Davidsz. de Heem (1606-1684) and one copy painting after De Heem by an unknown artist. MA-XRPD allowed to reveal and map the presence of in situ-formed alteration products. In the works examined, two rare lead arsenate minerals, schultenite (PbHAsO4) and mimetite (Pb-5(AsO4)(3)Cl), were encountered, both at and below the paint surface; they are considered to be degradation products of the pigments realgar (alpha-As4S4) and orpiment (As2S3). In transmission mode, the depletion of lead white, present in the (second) ground layer, could be seen, illustrating the intrusive nature of this degradation process. In reflection mode, several sulfate salts, palmierite (K2Pb(SO4)(2)), syngenite (K2Ca(SO4)(2)center dot H2O), and gypsum (CaSO4 center dot 2H(2)O), could be detected, in particular, at the (top) surface of the copy painting. Estimates for the information depth and sensitivity of both transmission and reflection mode MA-XRPD for various pigments have been made. The possibility of MA-XRPD to allow for noninvasive identification and visualization of alteration products is considered a significant advantage and unique feature of this method. MA-XRPD can thus provide highly relevant information for assessing the conservation state of artworks and could guide possible future restoration treatments.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000470793800031 Publication Date 2019-05-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited 5 Open Access  
  Notes ; The authors acknowledge financial support from BELSPO (Brussels) S2-ART and METOX projects, the NWO (The Hague) Science4Arts “ReVisRembrandt” project, and the GOA Project Solarpaint (University of Antwerp Research Council). The authors thank the Rijksmuseum, the Royal Museum of Fine Arts Antwerp, and their staff for the collaborations. ; Approved Most recent IF: 6.32  
  Call Number UA @ admin @ c:irua:160245 Serial 5882  
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Author De Jong, M.; Sleegers, N.; Florea, A.; Van Loon, J.; van Nuijs, A.L.N.; Samyn, N.; De Wael, K. url  doi
openurl 
  Title Unraveling the mechanisms behind the complete suppression of cocaine electrochemical signals by chlorpromazine, promethazine, procaine, and dextromethorphan Type A1 Journal article
  Year 2019 Publication Analytical chemistry Abbreviated Journal Anal Chem  
  Volume 91 Issue 24 Pages 15453-15460  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Toxicological Centre; Product development  
  Abstract The present work investigates the challenges accompanied by the electrochemical cocaine detection in physiological conditions (pH 7) in the presence of chlorpromazine, promethazine, procaine, and dextromethorphan, frequently used cutting agents in cocaine street samples. The problem translates into the absence of the cocaine oxidation signal (signal suppression) when in a mixture with one of these compounds, leading to false negative results. Although a solution to this problem was provided through earlier experiments of our group, the mechanisms behind the suppression are now fundamentally investigated via electrochemical and liquid chromatography quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) strategies. The latter was used to confirm the passivation of the electrodes due to their interaction with promethazine and chlorpromazine. Electron transfer mechanisms were further identified via linear sweep voltammetry. Next, adsorption experiments were performed on the graphite screen printed electrodes both with and without potential assistance in order to confirm if the suppression of the cocaine signals is due to passivation induced by the cutting agents or their oxidized products. The proposed strategies allowed us to identify the mechanisms of cocaine suppression for each cutting agent mentioned. Suppression due to procaine and dextromethorphan is caused by fouling of the electrode surface by their oxidized forms, while for chlorpromazine and promethazine the suppression of the cocaine signal is related to the strong adsorption of these (nonoxidized) cutting agents onto the graphite electrode surface. These findings provide fundamental insights in possible suppression and other interfering mechanisms using electrochemistry in general not only in the drug detection sector.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000503910600018 Publication Date 2019-11-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.32 Times cited Open Access  
  Notes ; The authors acknowledge financial support from IOF-SBO/POC (UAntwerp) and the Fund for Scientific Research (FWO) Flanders, Grant 1S 37658 17N. ; Approved Most recent IF: 6.32  
  Call Number UA @ admin @ c:irua:165727 Serial 5887  
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Author Ghimire, B.; Szili, E.J.; Lamichhane, P.; Short, R.D.; Lim, J.S.; Attri, P.; Masur, K.; Weltmann, K.-D.; Hong, S.-H.; Choi, E.H. pdf  url
doi  openurl
  Title The role of UV photolysis and molecular transport in the generation of reactive species in a tissue model with a cold atmospheric pressure plasma jet Type A1 Journal article
  Year 2019 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 114 Issue 9 Pages 093701  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Cold atmospheric pressure plasma jets (plasma) operated in ambient air provide a rich source of reactive oxygen and nitrogen species (RONS), which are known to influence biological processes important in disease. In the plasma treatment of diseased tissue such as subcutaneous cancer tumors, plasma RONS need to first traverse an interface between the plasma-skin surface and second be transported to millimeter depths in order to reach deep-seated diseased cells. However, the mechanisms in the plasma generation of RONS within soft tissues are not understood. In this study, we track the plasma jet delivery of RONS into a tissue model target and we delineate two processes: through target delivery of RONS generated (primarily) in the plasma jet and in situ RONS generation by UV photolysis within the target. We demonstrate that UV photolysis promotes the rapid generation of RONS in the tissue model target’s surface after which the RONS are transported to millimeter depths via a slower molecular process. Our results imply that the flux of UV photons from plasma jets is important for delivering RONS through seemingly impenetrable barriers such as skin. The findings have implications not only in treatments of living tissues but also in the functionalization of soft hydrated biomaterials such as hydrogels and extracellular matrix derived tissue scaffolds.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000460820600048 Publication Date 2019-03-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 12 Open Access Not_Open_Access  
  Notes National Research Foundation of Korea, NRF-2016K1A4A3914113 ; Australian Research Council, DP16010498 ; This work was supported by the National Research Foundation of Korea (NRF) Grant No. NRF-2016K1A4A3914113 and in part by Kwangwoon University 2018, Korea. E.J.S., S.-H.H., and R.D.S. wish to thank the Australian Research Council for partially supporting this research through Discovery Project No. DP16010498 and UniSA through the Vice Chancellor Development Fund. Approved Most recent IF: 3.411  
  Call Number PLASMANT @ plasmant @UA @ admin @ c:irua:158111 Serial 5159  
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Author Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. pdf  url
doi  openurl
  Title Spectroscopic coincidence experiments in transmission electron microscopy Type A1 Journal article
  Year 2019 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 114 Issue 14 Pages 143101  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We demonstrate the feasibility of coincidence measurements on a conventional transmission electron microscope, revealing the temporal

correlation between electron energy loss spectroscopy (EELS) and energy dispersive X-ray (EDX) spectroscopy events. We make use of a

delay line detector with ps-range time resolution attached to a modified EELS spectrometer. We demonstrate that coincidence between both

events, related to the excitation and deexcitation of atoms in a crystal, provides added information not present in the individual EELS or

EDX spectra. In particular, the method provides EELS with a significantly suppressed or even removed background, overcoming the many

difficulties with conventional parametric background fitting as it uses no assumptions on the shape of the background, requires no user input

and does not suffer from counting noise originating from the background signal. This is highly attractive, especially when low concentrations

of elements need to be detected in a matrix of other elements.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000464450200022 Publication Date 2019-04-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN (up) 0003-6951 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 18 Open Access OpenAccess  
  Notes Fonds Wetenschappelijk Onderzoek, G093417 ; Horizon 2020 Framework Programme, 823717 ESTEEM3 ; Helmholtz Association, VH-NG-1327 ; Approved Most recent IF: 3.411  
  Call Number EMAT @ emat @UA @ admin @ c:irua:159155 Serial 5168  
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