TY - JOUR A1 - Müller, M. A1 - Kaiser, Martin A1 - Stachowski, G.M. A1 - Resch-Genger, Ute A1 - Gaponik, N. A1 - Eychmüller, A. T1 - Photoluminescence quantum yield and matrix-induced luminescence enhancement of colloidal quantum dots embedded in ionic crystals N2 - The incorporation of colloidal quantum dots (QDs) into solid matrices, especially ionic salts, holds several advantages for industrial applications. Here, we demonstrated via absolute measurements of photoluminescence quantum yields (PL-QY) that the photoluminescence of aqueous CdTe QDs can be considerably increased upon incorporation into a salt matrix with a simple crystallization procedure. Enhancement factors of up to 2.8 and a PL-QY of 50 to 80%, both in NaCl crystals and incorporated in silicone matrices, were reached. The fact that the achievable PL enhancement factors depend strongly on PL-QY of the parent QDs can be described by the change of the dielectric surrounding and the passivation of the QD surface, modifying radiative and nonradiative rate constants. Time-resolved PL measurements revealed noncorrelating PL lifetimes and PL-QY, suggesting that weakly emissive QDs of the ensemble are more affected by the enhancement mechanism, thereby influencing PL-QY and PL lifetime in a different manner. PY - 2014 DO - https://doi.org/10.1021/cm5009043 SN - 0897-4756 SN - 1520-5002 VL - 26 IS - 10 SP - 3231 EP - 3237 PB - American Chemical Society CY - Washington, DC AN - OPUS4-31074 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mitova, M. A1 - Iliev, M. A1 - Nováková, A. A1 - Gorbushina, Anna A1 - Groudeva, V.I. A1 - Martin-Sanchez, Pedro Maria T1 - Diversity and biocide susceptibility of fungal assemblages dwelling in the Art Gallery of Magura Cave, Bulgaria N2 - Magura Cave, north-western Bulgaria, possesses valuable rock-art paintings made with bat guano and dated from the period between the Eneolithic and Bronze Ages. Since 2008, the Art Gallery is closed to the general public in order to protect the paintings from vandalism, microclimatic changes caused by visitors and artificial illumination, and the consequent growth of fungi and phototrophs. Nevertheless, some tourist visits are allowed under the supervision of cave managers. This study provides the first scientific report on cultivable fungal assemblages dwelling different substrata in the Art Gallery. A total of 78 strains, belonging to 37 OTUs (Ascomycota 81%, Zygomycota 13%, Basidiomycota 5%), were isolated in the study. This fungal diversity was clearly dominated by Penicillium (50% of strains) and Aspergillus (13%). The most relevant visible fungal colonies were detected in sediments rich in bat guano, where, besides Penicillium, other guanophilic fungi such as Mucor, Mortierella, Trichosporon and Trichoderma were dominant. Conversely, scarce fungi were detected on rock surface of painted walls. Based on the biocide susceptibility assay, octylisothiazolinone (OIT) and benzalkonium chloride (BAC) were effective inhibiting the in vitro growth of dominant fungal species in Magura Cave, when applied at concentrations ranged from 100 to 1,000 mg/L. These data provide a valuable knowledge about Magura fungi, and exemplify a type of preliminary test that may be conducted before planning any biocide treatment. However, considering the irreversible effects of biocides on the ecological balance in caves, and the low fungal contamination in painted walls of Magura Cave, there is no reason to use conventional biocides in this cave. Further studies, monitoring microbial communities and microclimatic parameters, should be conducted to improve the knowledge on microbial ecology in Magura Cave and possible human impacts, as well as to allow the early detection of potential microbial outbreaks. KW - Fungi KW - Rock-art caves KW - Biocides PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-397436 DO - https://doi.org/10.5038/1827-806X.46.1.2061 SN - 0392-6672 VL - 46 IS - 1 SP - 67 EP - 80 PB - Scholar Commons CY - Tampa, FL, USA AN - OPUS4-39743 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Wiesler, F. A1 - Hund-Rinke, K. A1 - George, E. A1 - Greef, J.-M. A1 - Holz, F. A1 - Hölze, L.E. A1 - Hülsbergen, K.-J. A1 - Martin, S. A1 - Severin, K. A1 - Spielvogel, S. A1 - Geiger, P. A1 - Nawotke, C. A1 - Kehlenbeck, H. A1 - Schenkel, H. A1 - Adam, Christian A1 - Bloem, E. A1 - Frank, D. A1 - Goldbach, H.E. A1 - Heene, M. A1 - Kratz, S. A1 - Kruse, A. A1 - Möller, K. A1 - Pinnekamp, J. A1 - Schoumans, O.F. A1 - Vogel, Christian A1 - Wulf, S. T1 - Recyclingphosphate in der Düngung – Nutzen und Grenzen N2 - Weltweit werden etwa 80–85 % aller abgebauten Rohphosphate für die Produktion von Düngemitteln verwendet. Bei noch steigendem Bedarf an Phosphor (P) geht man derzeit davon aus, dass die weltweiten P-Reserven noch über 200 Jahre ausreichen. Um den P-Vorrat langfristig abzusichern, sollte der in Reststoffen enthaltene Phosphor möglichst umfänglich genutzt werden. Dieser Forderung trägt das von der Bundesregierung 2012 erstmals beschlossene Deutsche Ressourceneffizienzprogramm ProgRess Rechnung. Rohphosphat wird auch seitens der Europäischen Kommission aufgrundseiner ökonomischen Bedeutung und des unsicheren Angebots als „kritischer Rohstoff“ eingestuft. Vor diesem Hintergrund hat die Bundesregierung in der Verordnung zur Neuordnung der Klärschlammverwertung vom 27. September 2017 in Deutschland eine verpflichtende technische Rückgewinnung von Phosphor für Abwasserbehandlungsanlagen ab einer Ausbaugröße von 100.000 Einwohnerwerten (12 Jahre nach Inkrafttreten der Verordnung) bzw. ab einer Ausbaugröße von über 50.000 Einwohnerwerten (15 Jahre nach Inkrafttreten der Verordnung) vorgeschrieben. Die Verordnung enthält keine Vorgaben hinsichtlich der anzuwendenden Technologie bei der Phosphorrückgewinnung. Ausgenommen von der Rückgewinnungspflicht sind Klärschlämme mit niedrigen Phosphorgehalten (weniger als 20 Gramm Phosphor je Kilogramm Klärschlamm-Trockenmasse). Auch die im Jahre 2017 verabschiedeten neuen Rechtsvorschriften für die Düngung verlangen zukünftig einen nachhaltigen und ressourceneffizienten Umgang mit Nährstoffen bei der landwirtschaftlichen Erzeugung und schränken die P-Zufuhr insbesondere auf hoch versorgten Böden ein (Düngeverordnung vom 26. Mai 2017). Dies wird zu einem mehr am Pflanzenbedarf orientierten und ggf. vermehrt überbetrieblichen Einsatz von wirtschaftseigenen Düngern führen. Um den politischen und gesetzlichen Anforderungen gerecht zu werden, müssen einerseits wirksame und kosteneffiziente technische Verfahren zum P-Recycling (weiter)entwickelt werden. Andererseits müssen die Recyclingprodukte die Anforderungen für eine direkte Verwendung in der Landwirtschaft oder als Rohstoff für die Herstellung von Düngemitteln erfüllen. In dem vorliegenden Standpunkt wird zunächst der potenzielle Beitrag von Reststoffen zur Deckung des P-Bedarfs in der deutschen Pflanzenproduktion geschätzt. Für die wichtigsten Reststoffe werden technische Verfahren zur P-Rückgewinnung bzw. Aufarbeitung skizziert. Auf Basis der Anforderungen der Landwirtschaft bzw. der Düngemittelindustrie an die P-Recyclingprodukte werden deren Herstellungsverfahren bewertet. Schließlich wird der Regelungs- und Forschungsbedarf formuliert. KW - Phosphor KW - Düngemittel KW - Diffusive Gradients in thin films (DGT) PY - 2020 SP - 1 EP - 19 PB - Bundesministerium für Ernährung und Landwirtschaft (BMEL) CY - Berlin AN - OPUS4-51011 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Babutzka, Martin A1 - Burkert, Andreas A1 - Heise, Svenja A1 - Heyn, A. T1 - Korrosionsuntersuchungen mit gelartigen Elektrolyten an Zink - Eine innovative Prüfmethodik N2 - Ein neuer Ansatz bei elektrochemischen Korrosionsuntersuchungen kann durch den Einsatz von gelartigen Elektrolyten als Alternative zu wässrigen Prüfelektrolyten beschritten werden. Gelartige Elektrolyte ermöglichen minimalinvasive Untersuchungen an natürlich gebildeten Zinkdeckschichten. Dadurch können korrosionsrelevante Kennwerte ermittelt werden, die Aussagen zur Deckschichtbildung und zur Stabilität von atmosphärisch gebildeten Deckschichten erlauben. In diesem Beitrag wird anhand verschiedener Untersuchungen an Reinzink der Mehrwert von gelartigen Elektrolyten für die Korrosionsforschung und -prüfung verdeutlicht. Darüber hinaus werden neue Erkenntnisse zur Deckschichtbildung von Zink unter atmosphärischen Bedingungen vorgestellt. T2 - GfKORR-Jahrestagung 2019 CY - Frankfurt a. M. DA - 12.11.2019 KW - Zink KW - Gelartige Elektrolyte KW - Korrosionsuntersuchungen KW - Deckschichtbildung PY - 2019 SN - 978-3-935406-71-0 SP - 53 EP - 64 AN - OPUS4-49642 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin A1 - Schilling, O. A1 - Kuschke, Christian A1 - Darnstädt, A. A1 - Schubert, Sven A1 - Günther, U. A1 - Wille, Frank T1 - Requirements for management systems for manufacturing of transport packages: the new revision of BAM-GGR 011 guideline N2 - In accordance with IAEA SSR-6 para 306 a management system shall be established and implemented to ensure compliance with the relevant provisions of the IAEA regulations. BAM has issued an update of the guideline: the BAM-GGR 011. The new revision describes necessary quality assurance measures for design, manufacture, testing, documentation, use, maintenance and inspection of packagings for package designs requiring competent authority approval for the transport of radioactive material. The measures can be categorised as system-related and design-related. They are independently approved and monitored by the German competent authority BAM and its authorised expert (BAM/T). The qualification of the organisation applying for the design approval certificate is reviewed in the context of the design approval procedure. The quality assurance measures for manufacture consist of three main steps. Pre-assessment of manufacturing documents such as quality plans, specifications etc., Manufacturing inspections according the pre-assessed documents and inspection before commissioning including documentation review. Periodic inspections during operation as well as relevant specifications for use and maintenance ensure that the properties specified in the approval certificate are preserved over the package life time. Special provisions for the return on experience regarding operational feedback for design, manufacture, use, maintenance and inspection are given. Special focus shall be given here to the rearranged and meanwhile established system of manufacturing inspections. This includes more transparent roles for a) the Producers authorised inspection 11282 representative, b) the independent inspection expert (S), acting on behalf of the manufacturer with acceptance of BAM, and c) BAM or its authorised expert (BAM/T). Additional attention shall be drawn to the management of deviations during manufacturing and provisions for maintenance and periodic inspections. T2 - 19th International Symposium on the Packaging and Transportation of Radioactive Materials PATRAM 2019 CY - New Orleans, LA, USA DA - 04.08.2019 KW - Quality assurance KW - Transport KW - Manufacturing KW - Surveillance KW - Radioactive material PY - 2019 SP - Paper 1128, 1 AN - OPUS4-49059 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Hüllmann, Dino A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Dzierliński, M. A1 - Lilienthal, A. J. A1 - Bartholmai, Matthias T1 - Aerial-based gas tomography – from single beams to complex gas distributions N2 - In this paper, we present and validate the concept of an autonomous aerial robot to reconstruct tomographic 2D slices of gas plumes in outdoor environments. Our platform, the so-called Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), combines a lightweight Tunable Diode Laser Absorption Spectroscopy (TDLAS) gas sensor with a 3-axis aerial stabilization gimbal for aiming at a versatile octocopter. While the TDLAS sensor provides integral gas concentration measurements, it does not measure the distance traveled by the laser diode’s beam nor the distribution of gas along the optical path. Thus, we complement the set-up with a laser rangefinder and apply principles of Computed Tomography (CT) to create a model of the spatial gas distribution from a set of integral concentration measurements. To allow for a fundamental ground truth evaluation of the applied gas tomography algorithm, we set up a unique outdoor test environment based on two 3D ultrasonic anemometers and a distributed array of 10 infrared gas transmitters. We present results showing its performance characteristics and 2D plume reconstruction capabilities under realistic conditions. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). KW - Aerial robot olfaction KW - Mobile robot olfaction KW - Gas tomography KW - TDLAS KW - Plume PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487843 DO - https://doi.org/10.1080/22797254.2019.1640078 SP - 1 EP - 16 PB - Taylor & Francis CY - London AN - OPUS4-48784 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Musil, B. A1 - Böhning, Martin A1 - Johlitz, M. A1 - Lion, A. T1 - On the inhomogenous chemo-mechanical ageing behaviour of nitrile rubber: experimental investigations, modelling and parameter identification N2 - Elastomers are used in almost all areas of industrial applications, such as tires, engine mounts, bridge bearings, seals or coatings. During their use in operation, they are exposed to different environmental influences. These include, in particular, climatic factors such as air oxygen, high temperatures, light (UV radiation) and the influence of media (e.g. oils, fuels). A very important result of these factors is the chemical ageing of elastomers. In this case, the elastomer degenerates and changes its chemical structure in the aged regions, which leads to an irreversible change in the material properties in connection with the reduction in its usability. In this paper, chemical ageing of nitrile butadiene rubber (NBR) is investigated. Especially in case of thermo-oxidative ageing at elevated operating temperatures, the ageing processes run inhomogeneously. These effects are known as diffusion-limited oxidation (DLO) and are associated with the diffusion–reaction behaviour of atmospheric oxygen with the elastomer network. For these reasons, NBR samples are artificially aged in air and subjected to different experimental methods, which are presented and discussed. Additional results from inhomogeneous mechanical tests and permeation tests indicate the causes of the DLO-effect, show the influence of chemical ageing and are subsequently used for parameter identification in relation to the diffusion–reaction equation. A continuum-mechanical modelling approach is also presented here, which describes the finite hyperelasticity, diffusion–reaction processes as well as chemical degradation and reformation of the elastomer network. This multifield problem leads to a system of partial and ordinary differential equations and constitutive equations and is solved within the finite element method. KW - Rubber KW - Ageing KW - Gas permeability KW - DLO KW - NBR PY - 2019 DO - https://doi.org/10.1007/s00161-019-00791-1 SN - 0935-1175 SN - 1432-0959 VL - 32 IS - 1 SP - 127 EP - 146 PB - Springer CY - Heidelberg AN - OPUS4-48560 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zakel, S. A1 - Schröder, Volkmar A1 - Askar, Enis A1 - Gabel, D. A1 - Hirsch, W. A1 - Kleinert, J. A1 - Krause, U. A1 - Krietsch, Arne A1 - Meistes, J. A1 - Sachtleben, A. A1 - Schmidt, Martin T1 - Sicherheitstechnische Kenngrößen des Explosionsschutzes von hybriden Stoffgemischen - Normungsfähige Bestimmungsverfahren N2 - In diesem Verbundvorhaben werden standardisierte Messverfahren für hybride Gemische erarbeitet, die der Bestimmung sicherheitstechnischer Kenngrößen des Explosionsschutzes dienen. Unter einem hybriden Gemisch wird dabei ein mehrphasiges System aus Brenngas oder brennbarem Dampf, sowie Luft und brennbarem Staub verstanden. Die Veröffentlichung der Ergebnisse erfolgt in einem Abschlussbericht und als DIN-Spezifikation (DIN SPEC). Diese DIN SPEC versetzt Prüfinstitute und Industrie in die Lage, Explosionsgefahren beim Betrieb technischer Anlagen mit hybriden Gemischen einzuschätzen und damit Prozesse sowohl sicherer als auch effizienter zu steuern. Dieses Projekt wird im Rahmen des WIPANOProgramms (Wissens- und Technologietransfer durch Patente und Normen) vom BMWi gefördert. T2 - 14. Fachtagung Anlagen-, Arbeits- und Umweltsicherheit CY - Köthen, Germany DA - 07.11.2019 KW - Explosionsschutz KW - Sicherheitstechnische Kenngrößen KW - Hybride Gemische KW - Normung PY - 2019 SN - 978-3-89746-220-5 SP - 73 CY - Frankfurt am Main AN - OPUS4-49954 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schumm, A. A1 - Martin, E. A1 - Beaumont, M. A1 - Ewert, Uwe A1 - Kolkoori, Sanjeevareddy A1 - Zscherpel, Uwe A1 - Wrobel, Norma A1 - Redmer, Bernhard T1 - A comparative study on the performance of digital detector systems for high energy applications N2 - For cast components reaching or exceeding total material thicknesses of 150mm, high energy sources such as linear accelerators or Betatrons are required in order to obtain reasonable exposure times. In this study, the performance of digital detector systems, involving imaging plates (IP) and digital detector arrays (DDA), was evaluated with respect to the testing class B requirements as formulated in the standard EN ISO 17636-2. As a reference, traditional radiographic film and a Cobalt-60 source was used. With film exposures, testing class B was achieved with Co-60 and Betatron (7.5 MV) at longer exposure times. The preliminary results show that the testing class B was not obtained with the examined digital detector arrays (DDA) and the high resolution imaging plates (IP) , even at 40, 60 and 80 minutes exposure time with a 7.5 MV Betatron. Class A was achieved using high resolution imaging plates with optimized metal filters between object and IPs and a high resolution DDA with intermediate Cu filters. Class A was also achieved applying a DDA with lower basic spatial resolution than required by Table B.13 of EN ISO 17636-2, but using the compensation principle as described in this standard. The next generation of digital detector arrays might potentially be able to obtain class B performance with the expected spatial resolution and sensitivity improvements. T2 - ECNDT 2014 - 11th European conference on non-destructive testing CY - Prague, Czech Republic DA - 06.10.2014 KW - Radiography KW - Image quality KW - Betatron KW - Digital detector array (DDA) KW - Casting KW - Standards KW - High energy radiography KW - Comparison of detectors KW - Steel weldment PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-323075 UR - https://www.ndt.net/?id=16394 SN - 1435-4934 VL - 19 IS - 12 SP - 1 EP - 6 PB - NDT.net CY - Kirchwald AN - OPUS4-32307 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Guilherme, A. A1 - Buzanich, Günter A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Coroado, J. A1 - Dos Santos, J.M.F. A1 - Carvalho, M.L. T1 - Synchrotron micro-XRF with compound refractive lenses (CRLs) for tracing key elements on Portuguese glazed ceramics N2 - Several glazed ceramic fragments (XVIth to XVIIIth centuries) from two production centers in Portugal (Coimbra and Lisbon) were the object of this study. The ones from Coimbra comprise two sets of samples: faiences and tiles. The ones from Lisbon are only tiles (azulejos, in Portuguese). The three main divisions of such pieces are the ceramic support (body), glaze and surface decoration. The system decoration/glaze is not easy to investigate, due to the high heterogeneity resulting from the mixing procedures and firing temperatures used. Moreover, the ability of the pigment to diffuse into the base glaze varies depending on the composition of both the pigment and the glaze in terms of fusibility. In order to raster these effects, high resolution techniques are required. In this work, synchrotron micro-X-ray fluorescence (µ-XRF) analysis was performed to monitor the profiles of the characteristic elements from the colors used and the glaze in well prepared cross-sections of the samples. Key elements are: Co for blue, Mn for purple, Cu for green, Sb for yellow, Pb for the glaze and Fe for the body. The major difference observed is that faiences have glaze thicknesses between 150 and 200 µm and tiles have glaze thicknesses between 350 and 400 µm. Furthermore, in faiences all the pigments except the yellow ones are well dispersed into the glassy matrix, while in tiles, all of them are just partially diffused throughout the glaze. However, differences between the tiles from Coimbra and Lisbon were observed. In the samples from Lisbon, a higher intake from the pigment throughout the glaze is observed. KW - Synchrotron micro-XRF KW - Compound refractive lenses (CRLs) KW - Portuguese glazed ceramics PY - 2012 DO - https://doi.org/10.1039/c2ja30030c SN - 0267-9477 SN - 1364-5544 VL - 27 IS - 6 SP - 966 EP - 974 PB - Royal Society of Chemistry CY - London AN - OPUS4-26789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bjeoumikhov, A. A1 - Bjeoumikhova, Zemfira A1 - Riesemeier, Heinrich A1 - Radtke, Martin A1 - Wedell, R. T1 - Propagation of synchrotron radiation through nanocapillary structures N2 - The propagation of synchrotron radiation through nanocapillary structures with channel sizes of 200 nm and periods in the micrometer size has been studied experimentally. It was shown that the propagation through individual capillary channels has a mode formation character. Furthermore it was shown that during the propagation through capillary channels the coherence of synchrotron radiation is partially conserved. Interference of beams propagating through different capillary channels is observed which leads to a periodically modulated distribution of the radiation intensity in a plane far from the exit of the structure. These investigations are of high relevance for the understanding of X-ray transmission through nanocapillaries and the appearance of wave properties at this size scale. KW - Polycapillary structure KW - Nanocapillary KW - X-ray optics KW - Wave properties KW - Synchrotron radiation KW - X-ray diffraction PY - 2007 DO - https://doi.org/10.1016/j.physleta.2007.01.092 SN - 0031-9163 SN - 0375-9601 VL - 366 IS - 4-5 SP - 283 EP - 288 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-20580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tissot, I. A1 - Troalen, L.G. A1 - Manso, M. A1 - Ponting, M. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Barreiros, M. A. A1 - Shaw, I. A1 - Carvalho, M.L. A1 - Guerra, M.F. T1 - A multi-analytical approach to gold in Ancient Egypt: Studies on provenance and corrosion N2 - Recent results from a three-year multi-disciplinary project on Ancient Egyptian gold jewellery revealed that items of jewellery from the Middle Kingdom to the New Kingdom were manufactured using a variety of alluvial gold alloys. These alloys cover a wide range of colours and the majority contain Platinum Group Elements inclusions. However, in all the gold foils analysed, these inclusions were found to be absent. In this work a selection of gilded wood and leather items and gold foil fragments, all from the excavations by John Garstang at Abydos (primarily from Middle Kingdom graves), were examined using Scanning Electron Microscopy-Energy Disperse Spectroscopy (SEM-EDS), X-Ray Fluorescence (µXRF), Particle Induced X-Ray Emission (µPIXE) and Double Dispersive X-Ray Fluorescence (D²XRF). The work allowed us to characterise the composition of the base-alloys and also to reveal the presence of Pt at trace levels, confirming the use of alluvial gold deposits. Corrosion products were also investigated in the foils where surface tarnish was visually observed. Results showed that the differences in the colour of corrosion observed for the foils are related not only to the thickness of the corrosion layer but also to a multi-layer structure containing the various corrosion products. KW - Gold KW - Egypt KW - PGE KW - Provenance KW - Corrosion KW - muXRF KW - muPIXE KW - D2XRF KW - SEM-EDS PY - 2015 DO - https://doi.org/10.1016/j.sab.2015.03.012 SN - 0584-8547 SN - 0038-6987 VL - 108 SP - 75 EP - 82 PB - Elsevier CY - Amsterdam AN - OPUS4-33155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lutz, C. A1 - Hampel, S. A1 - Beuermann, S. A1 - Turek, T. A1 - Kunz, U. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Fittschen, U. E. A. T1 - Investigation on Vanadium Species Distribution in Nafion™ 117 after Cyclization in a Vanadium Redox Flow Battery N2 - The vanadium redox flow battery (VRFB) is currently a potential candidate for stationary energy storage. A major challenge is the unintended vanadium transport through the separator, which results in a fade of capacity. To overcome this issue, it is necessary to understand the transport processes in the membrane on a more fundamental level. In this work, the vanadium species distribution in Nafion™ 117 after cyclization was investigated. Two membranes, one from a charged VRFB and another from a discharged VRFB, were analyzed using ultraviolet–visible spectroscopy (UV/VIS) and X-ray absorption near edge structure spectroscopy (XANES). Little difference between the two membranes was recognizable according to the UV/VIS results. In comparison, the XANES results showed that the membrane from the charged VRFB contains more V3+ than VO2+, whereas for the discharged case, more VO2+ is present in the membrane. KW - Synchrotron KW - BAMline KW - XANES KW - Vanadium redox flow battery PY - 2021 VL - 64 SP - 1 EP - 8 AN - OPUS4-54144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Simons, C. A1 - Mans, C. A1 - Hanning, S. A1 - Janßen, A. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Ostermann, Markus A1 - Michaelis, Matthias A1 - Wienold, Julia A1 - Alber, D. A1 - Kreyenschmidt, M. T1 - Study on microscopic homogeneity of polymeric candidate reference materials BAM H001-BAM H010 by means of synchrotron µ-XRF and LA-ICP-MS N2 - In this study the microscopic homogeneity of the newly developed plastic reference materials BAM H001-BAM H010 was investigated. The materials consist of an acrylonitryle-butadien-styrene terpolymer, doped with different amounts of the elements Br, Cd, Cr, Hg and Pb. For the quantitative determination of the degree of homogeneity, a procedure proposed by Kempenaers et al. (Fresenius J. Anal. Chem., 2001, 369, 733-737) was used. On every sample an extensive number of different points were analyzed and standard deviation for every element mentioned above was used to calculate a minimal sampling mass that is necessary to reach a certain level of uncertainty caused by inhomogeneity (mmin,5%). The experiments were taken out with synchrotron µ-XRF (SR µ-XRF) at BESSYII in Berlin and by laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS). The calculated values for mmin,5% of both techniques showed comparable results for all elements. It could be shown that the materials are suitable for calibration of micro analytic techniques if at least 64 µg are used. KW - XRF KW - LA-ICP-MS KW - RoHS KW - CRM PY - 2010 DO - https://doi.org/10.1039/b917008a SN - 0267-9477 SN - 1364-5544 VL - 25 SP - 40 EP - 43 PB - Royal Society of Chemistry CY - London AN - OPUS4-20938 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kühbacher, M. A1 - Weseloh, G. A1 - Bertelsmann, H. A1 - Özaslan, M. A1 - Radtke, Martin A1 - Riesemeier, Heinrich A1 - Kyriakopoulos, A. A1 - Behne, D. T1 - Analysis of metal- and metalloid-containing proteins by SRXRF at the BAMline N2 - Pilot studies have been carried out at the BAMline at BESSY II in collaboration with the Bundesanstalt für Materialforschung und -prüfung (BAM) on metal- and metalloid-containing compounds in biological samples after electrophoretic protein separation. After sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) and transfer onto a blotting membrane the distribution of selenium among the proteins of testis homogenate of a rat and a wallaby was determined. The comparison with the autoradiogram of 75Se-labeled proteins separated in the same way showed that of nine seleniumcontaining proteins found in rat testis homogenate by autoradiography four could be detected by synchrotron radiation X-ray fluorescence analysis (SRXRF). PY - 2003 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/berichte/bessy/annualreport2002.pdf#page=333 SN - 0179-4159 SP - 333 EP - 335 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-2495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reiche, I. A1 - Berger, Achim A1 - Duval, A. A1 - Guicharnaud, H. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Schäfer, D. A1 - Simon, R. T1 - SY-XRF study of Hans Baldung Grien silverpoint drawings and the silver stylus from the 'Karlsruhe sketchbook' N2 - We performed spatially resolved synchrotron-induced x-ray fluorescence analyses (SY-XRF) of five silverpoint drawings from the famous `Karlsruhe sketchbook´ and a silverpoint, which is assumed to be an original one used by the Renaissance artist Hans Baldung Grien (1484-1545) himself. The silverpoint, one out of a very small number of ancient styli conserved nowadays, is fixed on the so-called `Karlsruhe sketchbook´. Measurements were executed at the FLUO-TOPO beamline at the electron storage ring ANKA. It has been shown, that SY-XRF at this beamline is nondestructive and sensitive enough for the analysis of minor and major elements in the silver strokes. This study provides new insights into this graphical technique and ancient drawing instruments: results are that three drawings have been created with a common type of silverpoint containing about (10.4 ± 0.7) wt% of Cu. In all the cases, Hg at a 10% level by weight was identified in the strokes. Presence of Hg is not due to the original silver alloy, but is a result of a general alteration phenomenon of silverpoint drawings. This fact is confirmed by the analysis of the original silverpoint, which contains only small traces of Hg. The result for the copper content of the silverpoint (10.4 ± 1.7) wt% is in good agreement with that of these three drawings. It is supposable that the silverpoint found attached today served for the creation of the corresponding drawings. Moreover, the graphical technique of Baldung is found to be continual over three decades. Only one very late drawing dated to 1543 was probably realized with another silverpoint, containing about 3 wt% of Cu. This difference in the chemical composition of drawings from the late period might be used as a more precise dating indicator of Baldung drawings that are not clearly attributed to a certain period. KW - Synchrotron KW - XRF analysis KW - Drawings KW - Silver stylus PY - 2007 DO - https://doi.org/10.1002/xrs.963 SN - 0049-8246 VL - 36 IS - 3 SP - 173 EP - 177 PB - Wiley CY - Chichester AN - OPUS4-16150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vasilescu, A. A1 - Constantinescu, B. A1 - Stan, D. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Buzanich, Günter A1 - Ceccato, D. T1 - Studies on ancient silver metallurgy using SR XRF and micro-PIXE N2 - This work presents a complex evaluation of a series of Geto-Thracian silver adornments found on Romanian territory, part of the 4th century BC Agighiol (Northern Dobruja) hoard and of an ingot from the 1st century BC Geto-Dacian Surcea (Transylvania) hoard, using Synchrotron Radiation X-Ray Fluorescence and micro- Proton Induced X-ray Emission analysis and mapping in order to investigate aspects related to the elemental composition of the metal and the metallurgy implied in their manufacture. One of the samples can be linked to Laurion as the source of metal, and several items contain silver probably originated in Macedonia. The set of silver items was found to be heteregenous as composition and microstructure, and corrosion-related elements could be also identified in the X-Ray maps. KW - Synchrotron radiation XRF KW - Micro-PIXE KW - Archaeological silver PY - 2015 DO - https://doi.org/10.1016/j.radphyschem.2015.07.008 SN - 0969-806X SN - 0020-7055 SN - 0146-5724 VL - 117 SP - 26 EP - 34 PB - Pergamon Press CY - Oxford [u.a.] ; Frankfurt, M. AN - OPUS4-33809 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Denker, A. A1 - Hahn, Oliver A1 - Kanngießer, B. A1 - Malzer, W. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Röhrs, S. A1 - Reiche, I. A1 - Stege, H. T1 - Chemie der Kunst - Zerstörungsfreie Analyse von Kunst- und Kulturgütern N2 - Naturwissenschaftliche Informationen, insbesondere die chemische Zusammensetzung der Objekte, können Hinweise auf die Hintergründe der Objektherstellung liefern, die der alleinigen kunsthistorischen Begutachtung verborgen blieben. Es können nicht nur Fragen nach dem Prozess, Zeitpunkt und Ort der Herstellung beantwortet werden. Die chemische Analyse gibt auch Hinweise auf Ereignisse und Veränderungen, die erst nach der Fertigstellung des Objektes erfolgten. So werden Alterungsphänomene oder historische Überarbeitungen und Restaurierungen aufgedeckt, aber auch Konservierungsstrategien zur Erhaltung der Kunstwerke unterstützt. Durch den technologischen Fortschritt im Bereich der röntgenanalytischen Methoden, die berührungsfrei, ohne Probennahme und ohne Schädigung für das Untersuchungsobjekt arbeiten, erschließen sich dem Analytiker erstmalig Möglichkeiten, auch sehr wertvolle und fragile Objekte zerstörungsfrei zu untersuchen. PY - 2003 DO - https://doi.org/10.1515/mt-2003-0003 SN - 0025-5300 VL - 45 IS - 11-12 SP - 485 EP - 503 PB - Carl Hanser Verlag CY - München AN - OPUS4-2745 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Qureshi, Navid A1 - Morrow, Ryan A1 - Eltoukhy, Samar A1 - Grinenko, Vadim A1 - de Oliveira Guilherme Buzanich, Ana A1 - Onykiienko, Yevhen A. A1 - Kulbakov, Anton A1 - Inosov, Dmytro S. A1 - Adler, Peter A1 - Valldor, Martin T1 - Noncollinear Magnetic Structures in the Chiral Antiperovskite β-Fe2SeO N2 - We present the magnetic properties of the chiral, polar, andpossibly magnetoelectric antiperovskite β-Fe2SeO as derived from magnet-ization and specific-heat measurements as well as from powder neutrondiffraction and Mössbauer experiments. Our macroscopic data unambig-uously reveal two magnetic phase transitions at TN1 ≈ 103 K and TN2 ≈ 78K, while Rietveld analysis of neutron powder diffraction data reveals anoncollinear antiferromagnetic structure featuring magnetic moments inthe a−b plane of the trigonal structure and a ferromagnetic moment alongc. The latter is allowed by symmetry between TN1 and TN2, weakly visible inthe magnetization data yet unresolvable microscopically. While theintermediate phase can be expressed in the trigonal magnetic spacegroup P31, the magnetic ground state is modulated by a propagation vectorq = (1/2 1/2 0) resulting in triclinic symmetry and an even more complexlow-temperature spin arrangement which is also reflected in the Mö ssbauer hyperfine patterns indicating additional splitting of Fesites below TN2. The complex noncollinear spin arrangements suggest interesting magnetoelectric properties of this polar magnet. KW - EXAFS KW - Antiperovskite KW - Magnetic structure PY - 2024 DO - https://doi.org/10.1021/acs.inorgchem.4c02916 SN - 0020-1669 VL - 63 IS - 48 SP - 22712 EP - 22720 PB - American Chemical Society (ACS) AN - OPUS4-63116 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Curado, Jessica A1 - Radtke, Martin A1 - Buzanich, Günter A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Guttler, R.A.S. A1 - Rizzutto, M.A. T1 - μ-SRXRF characterization of Brazilian emeralds N2 - The aim of the present study is to characterize emeralds from different mines of Brazil by using Synchrotron Radiation X-ray Fluorescence Microanalysis (µ-SRXRF). The advantage of this technique is that we can analyze a homogeneous, inclusion free area of the stone with the microbeam to distinguish the elemental fingerprint according to the provenance of the emerald. A total of 47 samples belonging to 5 different Brazilian mines were studied in this work and 28 elements were identified. By means of Principal Component Analysis (PCA) it is possible to build different groups according to the provenance of the stones, which allows to assign samples of unknown origin to the according mine. T2 - 22nd International congress on X-ray optics and microanalysis CY - Hamburg, Germany DA - 02.09.2013 KW - µ-SRXRF KW - BAMline KW - Emeralds KW - Geoscience PY - 2014 DO - https://doi.org/10.1088/1742-6596/499/1/012016 SN - 1742-6588 SN - 1742-6596 VL - 499 SP - 012016-1 EP - 012016-5 PB - IOP Publ. CY - Bristol, UK AN - OPUS4-30541 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Heyn, A. T1 - Corrosion investigations by using gel-type electrolytes N2 - Limitations are encountered regarding the electrolyte when studying atmospheric corrosion reactions on materials that form protective layers on their surface or tend to passivate. For example, the reconstruction of a thin wet film, as well as the interpretation of electrochemical measurements in so-called bulk solutions (a "mass" of electrolyte), often proves to be difficult in view of corrosion behavior under atmospheric conditions. A new approach to this problem in corrosion research includes the use of gel-type electrolytes as an alternative to bulk electrolytes. Gel-type electrolytes form a thin wet film on the surface of the material, whereby the naturally formed protective layer is affected similar to atmospheric conditions and can be examined in an almost non-destructive way. Through electrochemical instrumentation specific values such as polarization resistances and corrosion currents can be determined providing information on kinetics of surface layer formation and stability of surface layers formed under the influence of a thin wet film. Thus, new test methods can be developed that supply a better understanding of corrosion processes in specific atmospheres. In this article different zinc coatings and aluminium alloys were investigated, their naturally formed protective layers were electrochemically characterized and corrosion relevant values were determined by using a gel pad based on polysaccharide. Corrosion relevant values allowed the differentiation of various coating systems and could describe the current protective effect provided by the coating. It is shown that gel-type electrolytes influence protective layers and coatings considerably less than corresponding bulk electrolytes and that an atmospheric wet film is approached by these test conditions. From the results it is evident that gel-type electrolytes represent a viable and promising field in corrosion research. T2 - 18th Chemnitz Seminar on Materials Engineering – 18. Werkstofftechnisches Kolloquium CY - Chemnitz, Germany KW - Corrosion investigations KW - Gel-type electrolytes KW - Zinc coatings PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-366680 DO - https://doi.org/10.1088/1757-899X/118/1/011002 VL - 118 SP - 17 PB - IOP Publishing CY - Bristol, UK AN - OPUS4-36668 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Merchel, Silke A1 - Berger, Achim A1 - Görner, Wolf A1 - Radtke, Martin A1 - Riesemeier, Heinrich A1 - Reiche, I. A1 - Riederer, J. A1 - Duval, A. A1 - Guicharnaud, H. T1 - Non-Destructive Investigations of Dürer's Silver Point Drawings by Pixe and SY-XRF T2 - 7th International Conference on Non-destructive testing and Microanalysis for the Diagnostics and Conservation of the Cultural and Environmental Heritage ; art 2002 CY - Antwerp, Belgium DA - 2002-06-02 PY - 2002 UR - http://srs.dl.ac.uk/arch/publications/reiche/reiche_fullcorr.pdf SP - 82 AN - OPUS4-1400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Reiche, I. A1 - Berger, Achim A1 - Duval, A. A1 - Görner, Wolf A1 - Guicharnaud, H. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Riederer, J. A1 - Riesemeier, Heinrich T1 - Traces of Albrecht Dürer: Non-destructive analyses of Renaissance silverpoint drawings KW - Nuclear industry KW - Nuclear medicine PY - 2004 SN - 92-0-114703-1 SN - 0074-1876 IS - 1181 SP - 138 EP - 142 PB - IAEA CY - Vienna AN - OPUS4-5548 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Reiche, I. A1 - Berger, Achim A1 - Duval, A. A1 - Görner, Wolf A1 - Guicharnaud, H. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Riederer, J. A1 - Riesemeier, Heinrich A1 - Roth, M. ED - Röhrs, S. T1 - Auf den Spuren Albrecht Dürers - Zerstörungsfreie Untersuchung von Silberstiftzeichnungen mittels Mikro-PIXE und Synchrotron-induzierter Mikro-RFA T2 - Jahrestagung 2003 im Ethnologischen Museum Berlin-Dahlem CY - Berlin, Deutschland DA - 2003-03-12 PY - 2003 SN - 3-00-014223-1 SN - 0949-4057 SP - 118 EP - 120 CY - [Frankfurt am Main] AN - OPUS4-2356 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Merchel, Silke A1 - Berger, Achim A1 - Görner, Wolf A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Vogl, Jochen A1 - Frisch, A. A1 - Reiche, I. T1 - Kunst- und Kulturgüter unter "Beschuss" T2 - GDCh-Jahrestagung Chemie 2003 ; Jahrestagung der Fachgruppe Nuklearchemie ; 19. Seminar Aktivierungsanalyse CY - München, Deutschland DA - 2003-10-06 PY - 2003 SN - 3-936028-14-1 N1 - Serientitel: Kurzreferate / GDCh-Jahrestagung Chemie 2003 – Series title: Kurzreferate / GDCh-Jahrestagung Chemie 2003 IS - 5 SP - 68 PB - Gesellschaft Deutscher Chemiker CY - Frankfurt am Main AN - OPUS4-2686 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Frisch, A. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Vogl, Jochen ED - Röhrs, S. T1 - Synchrotron-XRF und PIXE Untersuchungen an bronzezeitlichen Fussringen T2 - Jahrestagung 2003 im Ethnologischen Museum Berlin-Dahlem CY - Berlin, Deutschland DA - 2003-03-12 PY - 2003 SN - 3-00-014223-1 SN - 0949-4057 SP - 101 EP - 103 CY - [Frankfurt am Main] AN - OPUS4-2355 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reiche, I. A1 - Berger, Achim A1 - Duval, A. A1 - Görner, Wolf A1 - Guicharnaud, H. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Riederer, J. A1 - Riesemeier, Heinrich A1 - Roth, M. ED - Marabelli, M. ED - Tabaso, M. T1 - Spatially resolved SR-XRF analyses of complex drawings of the Holbein family T2 - 8th International Conference on "Non-Destructive Investigations and Microanalysis for the Diagnostics and Conservation of the Cultural and Environmental Heritage" CY - Lecce, Italy DA - 2005-05-15 KW - X-ray spectrometry KW - XRF KW - Röntgenfluoreszenzanalyse KW - RFA KW - Silverpoint drawing KW - Silberstiftzeichnung PY - 2005 SP - 7 pages PB - Italian Society of Non Destructive Testing CY - Lecce AN - OPUS4-7677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Berger, Achim A1 - Calligaro, T. A1 - Duval, A. A1 - Görner, Wolf A1 - Guerra, M.-F. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Reiche, I. A1 - Riesemeier, Heinrich A1 - Roth, M. T1 - Study of Ag and Au based historical and archaeological objects by high energy Sy-XRF KW - Synchrotron KW - XRF analysis KW - Drawings KW - Archaeometry KW - Gold KW - Röntgenfluoreszenzanalyse KW - RFA KW - Zeichnungen KW - Archäometrie KW - Albrecht Dürer KW - gold PY - 2004 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/berichte/bessy/annualreport2003.pdf#page=544 SN - 0179-4159 SP - 544 EP - 546 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-3507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Reiche, I. A1 - Berger, Achim A1 - Bevers, H. A1 - Dupuis, G. A1 - Duval, A. A1 - Görner, Wolf A1 - Guicharnaud, H. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Riederer, J. A1 - Riesemeier, Heinrich A1 - Roth, M. T1 - Spatially resolved SR-XRF analyses of complex drawings by the Holbein family and silverpoint drawings by Rembrandt KW - X-ray spectrometry KW - XRF KW - Röntgenfluoreszenzanalyse KW - RFA KW - Silverpoint drawing KW - Silberstiftzeichnung PY - 2005 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/berichte/bessy/annualreport2004.pdf#page=491 SN - 0179-4159 SP - 491 EP - 493 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-7380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Armbruster, B. A1 - Eilbracht, H. A1 - Grüger, A. A1 - Radtke, Martin A1 - Riesemeier, Heinrich A1 - Reiche, I. T1 - The Vikings in Berlin: SR-XRF analyses of the Hiddensee gold jewellery PY - 2005 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/infos/bessy/highlights2004.pdf#page=32 SN - 1611-6127 SP - 32 EP - 33 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-7386 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kanngießer, B. A1 - Malzer, W. A1 - Fuentes Rodriguez, A. A1 - Reiche, I. A1 - Voigt, F. A1 - Radtke, Martin T1 - 3D micro X-ray fluorescence spectroscopy - combining elemental analysis with chemical speciation PY - 2004 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/berichte/bessy/annualreport2003.pdf#page=495 SN - 0179-4159 SP - 495 EP - 497 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-3513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reiche, I. A1 - Berger, Achim A1 - Duval, A. A1 - Görner, Wolf A1 - Merchel, Silke A1 - Radtke, Martin A1 - Riederer, J. A1 - Riesemeier, Heinrich T1 - Metallstiftzeichnungen Albrecht Dürers KW - Synchrotron KW - XRF analysis KW - Drawings KW - Archaeometry KW - Röntgenfluoreszenzanalyse (RFA) KW - Zeichnungen KW - Archäometrie KW - Albrecht Dürer PY - 2004 SN - 1563-2628 VL - 5 IS - 2 SP - 30 EP - 38 PB - Foto Text Verl. CY - Stuttgart AN - OPUS4-3570 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Denker, A. A1 - Hahn, Oliver A1 - Merchel, Silke A1 - Radtke, Martin A1 - Kanngießer, B. A1 - Malzer, W. A1 - Röhrs, S. A1 - Reiche, I. A1 - Stege, H. T1 - Röntgenanalytik für Kunstwerke und Kulturgüter N2 - Naturwissenschaftler arbeiten mit Archäologen, Kunsthistorikern und Restauratoren zusammen, um Materialinformationen über Kunstwerke mit den Erkenntnissen aus Altertumsforschung, Kunstgeschichte und Denkmalpflege zu verbinden. Röntgenfluoreszenz und Röntgenemission sind die Methoden der Wahl, wenn wertvolle und fragile Objekte zerstörungsfrei zu untersuchen sind. KW - Synchrotron KW - XRF analysis KW - Drawings KW - Paintings KW - Ink KW - Art objects KW - Archaeometry KW - Röntgenfluoreszenzanalyse (RFA) KW - Zeichnungen KW - Gemälde KW - Tinten KW - Kunstobjekte KW - Archäometrie PY - 2005 SN - 1439-9598 SN - 1521-3854 VL - 53 IS - 2 SP - 118 EP - 123 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-6898 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Reiche, I. A1 - Berger, Achim A1 - Duval, A. A1 - Görner, Wolf A1 - Guicharnaud, H. A1 - Merchel, Silke A1 - Radtke, Martin A1 - Riederer, J. A1 - Riesemeier, Heinrich A1 - Roth, M. ED - Denker, A. ED - Adriaens, A. ED - Dowsett, M. ED - Giumlia-Mair, A. T1 - Synchrotron radiation and protons on the traces of famous artists - Non-destructive analyses of silverpoint drawings by Albrecht Dürer KW - X-ray spectrometry KW - XRF KW - Röntgenfluoreszenzanalyse KW - RFA KW - Silverpoint drawing KW - Silberstiftzeichnung PY - 2006 SN - 3-8167-7178-5 SP - 91 EP - 101 PB - Fraunhofer-IRB-Verl. CY - Stuttgart AN - OPUS4-14190 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wolff, Timo A1 - Hahn, Oliver A1 - Merchel, Silke A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Denker, A. T1 - Four non-destructive X-Ray methods analyzing corroded coins: A self-critical comparison T2 - Workshop Synchrotron Radiation in Art and Archaeology 2006 CY - Berlin, Germany DA - 2006-09-27 PY - 2006 AN - OPUS4-14229 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - von Bohlen, A. A1 - Hergenröder, R. A1 - Sternemann, C. A1 - Paulus, M. A1 - Radtke, Martin A1 - Riesemeier, Heinrich T1 - Wavelenght Dispersive Synchrotron Microprobe Used for Material Analysis N2 - Synchrotron radiation (SR) has been used in recent years as an excellent excitation source for X-ray fluorescence spectrometry. SR offers, in contrast to conventional X-ray sources, highly brilliant polychromatic, polarized radiation with which micro-domain X-ray fluorescence spectrometry becomes possible. A feasibility study of utility, conducted at BESSY (Berlin) and at DELTA (Dortmund), both synchrotron facilities of the third generation, to evaluate the use of wavelength dispersive X-ray fluorescence spectrometry in combination with synchrotron radiation is presented. First results for material analysis, obtained by combining the synchrotron radiation and a commercially available spectrometer commonly attached to a scanning electron microscope, are presented. The spectrometer, of the linear type, uses curved focusing Bragg-crystals of the Johann type which leads to a high spectral resolution up to 3 eV. Examples of micro-domain analyses are presented and compared with those obtained by synchrotron radiation induced energy dispersive X-ray fluorescence. KW - Synchrotron radiation KW - WDXRF KW - EDXRF KW - Micro analysis KW - Material analysis PY - 2005 DO - https://doi.org/10.1081/CI-200048048 SN - 1073-9149 SN - 1525-6030 VL - 33 IS - 2 SP - 137 EP - 150 PB - Dekker CY - New York, NY AN - OPUS4-14235 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reifschneider, O. A1 - Vennemann, A. A1 - Buzanich, Günter A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Hogeback, J A1 - Köppen, C. A1 - Großgarten, M. A1 - Sperling, M. A1 - Wiemann, M. A1 - Karst, U. T1 - Revealing Silver Nanoparticle Uptake by Macrophages Using SR-μXRF and LA-ICP-MS N2 - To better study the impact of nanoparticles on both in vitro and in vivo models, tissue distribution and cellular doses need to be described more closely. Here silver nanoparticles were visualized in alveolar macrophages by means of synchrotron radiation micro X-ray fluorescence spectroscopy (SR-μXRF) with high spatial resolution of 3 × 3 μm2. For the spatial allocation of silver signals to cells and tissue structures, additional elemental labeling was carried out by staining with eosin, which binds to protein and can be detected as bromine signal with SR-μXRF. The method was compatible with immunostaining of macrophage antigens. We found that the silver distribution obtained with SR-μXRF was largely congruent with distribution maps from a subsequent laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) of the same tissue sites. The study shows a predominant, though not exclusive uptake of silver into alveolar macrophages in the rat lung, which can be modeled by a similar uptake in cultured alveolar macrophages. Advantages and limitations of the different strategies for measuring nanoparticle uptake at the single cell level are discussed. KW - Synchrotron KW - BAMline KW - XRF KW - Nanoparticle KW - Macrophagen PY - 2020 DO - https://doi.org/10.1021/acs.chemrestox.9b00507 VL - 33 IS - 5 SP - 1250 EP - 1255 PB - American Chemical Society AN - OPUS4-50855 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vasilescu, A. A1 - Constantinescu, B. A1 - Bugoi, R. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Simon, R. ED - Denecke, M. ED - Walker, C. T1 - Gold provenance studies for Romanian archaeological objects using micro-SR-XRF N2 - Studies by Synchrotron Radiation-X-Ray Fluorescence (SR-XRF) for the search of the presence of trace elements like Sb, Sn, Te and Pb in archaeological metallic objects found on the territory of Romania-old coins and Bronze Age jewelry, aimed to determine the provenance of the gold used in their manufacture. The results are compared with the detailed elemental composition of alluvial or primary gold samples, obtained by the same technique. This work attempted to establish the origin of the gold used for the mint of two different types of koson coins. We found that the kosons with monogram are made of refined gold, while the one used for the kosons without monogram is mainly alluvial. The gold used in the manufacture of the Calarasi Vulchitrun-type disk and the Tauteu hair ring is also of alluvial origin. T2 - 20th International congress on X-ray optics and microanalysis CY - Karlsruhe, Germany DA - 2009-09-14 KW - Provenance KW - Gold KW - SR-XRF KW - Trace elements PY - 2010 UR - http://link.aip.org/link/?APCPCS/1221/139/1 SN - 978-0-7354-0764-0 DO - https://doi.org/10.1063/1.3399240 SN - 0094-243X SP - 139 EP - 143 PB - American Institute of Physics AN - OPUS4-21182 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Constantinescu, B. A1 - Vasilescu, A. A1 - Radtke, Martin A1 - Reinholz, Uwe T1 - A study on gold and copper provenance for Romanian prehistoric objects using micro-SR XRF N2 - This study intends to clarify the metal provenance of gold archaeological items using the variation of the Au–Ag ratio and the presence of trace elements as Sn, Sb, Te, and Pb, concentrating on gold Dacian Koson coins, recovered recently. It also extends the area of our investigations to the copper provenance of Bronze Age artifacts—axes, sickles, and celts—found on Romanian territory. The experiments were performed by micro-SR XRF at BESSY Berlin, at the BAM-line facility. Two types of coins (Koson, with and without monogram) were analysed. The conclusions we reached were that most of the monogram coins are made from refined gold (3–5% Ag, less than 0.5% Cu), while the without monogram coins are made from native Transylvanian gold (9–20% Ag, 0.5–2% Cu), of alluvial origin, proved by the presence of Sn, Sb and Te embedded in the gold. The problem of provenance for prehistoric Romanian copper and bronze objects consists in linking their elemental compositional patterns to the ones of the Bronze Age regional mines from Bulgaria, Serbia or Transylvania, most likely used as ore sources for their manufacture. The studied samples present relevant traces of As, Ag, Sb, and Co, suggesting the most probable use of copper from Serbia or northern Bulgaria for their manufacture. KW - X-ray fluorescence KW - Synchrotron radiation KW - Proton induced X-ray emission KW - Archaeometry KW - Gold PY - 2011 DO - https://doi.org/10.1039/c0ja00215a SN - 0267-9477 SN - 1364-5544 VL - 26 IS - 5 SP - 917 EP - 921 PB - Royal Society of Chemistry CY - London AN - OPUS4-23191 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brücher, M. A1 - von Bohlen, A. A1 - Jacob, P. A1 - Franzke, J. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Müller, Bernd R. A1 - Scharf, Oliver A1 - Hergenröder, R. T1 - The charge of solid-liquid interfaces measured by X-ray standing waves and streaming current N2 - Measurements of ion distributions at a charged solid–liquid interface using X-ray standing waves (XSW) are presented. High energy synchrotron radiation (17.48 keV) is used to produce an XSW pattern inside a thin water film on a silicon wafer. The liquid phase is an aqueous solution containing Br and Rb ions. The surface charge is adjusted by titration. Measurements are performed over a pH range from 2.2–9, using the native Si oxide layer and functional (amine) groups as surface charge. The Debye length, indicating the extension of the diffuse layer, could be measured with values varying between 1–4 nm. For functionalized wafers, the pH dependent change from attraction to repulsion of an ion species could be detected, indicating the isoelectric point. In combination with the measurement of the streaming current, the surface charge of the sample could be quantified. KW - Interfacial charge KW - Solid/liquid interfaces KW - Surface analysis KW - Surface functionalization KW - X-ray spectrometry KW - X-ray KW - Standing waves KW - XSW KW - Streaming current KW - Synchrotron radiation PY - 2010 DO - https://doi.org/10.1002/cphc.201000166 SN - 1439-4235 SN - 1439-7641 VL - 11 IS - 10 SP - 2118 EP - 2123 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-22057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Constantinescu, B. A1 - Vasilescu, A. A1 - Stan, D. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Buzanich, Günter A1 - Ceccato, D. A1 - Oberländer-Târnoveanu, E. T1 - Studies on archaeological gold items found in Romanian territory using X-ray-based analytical spectrometry N2 - This paper is an overview of the work developed by our group in the investigations of museum objects and alluvial gold, reflected in a series of studies published between 2000–2011, supplemented with new results, unpublished up-to-date. The X-ray based spectrometric techniques employed range from various X-Ray Fluorescence (XRF) investigations to ion beam analysis, including synchrotron radiation XRF and micro-Particle Induced X-ray Emission. The gold objects discussed are mainly part of the Sarmizegetusa Dacian hoards—spiraled bracelets (armbands) and coins. After obtaining in 2011 the permission of the Romanian authorities to take very small (1–2 mg) samples from the most 'unimportant' areas of the Dacian bracelets and several Koson staters, to analyze them by micro-SR-XRF at BESSY, in February 2012, the investigation of several micro-areas of 17 stater and 28 bracelet samples revealed important micro-structural inhomogeneity, especially in Sn and Cu. The same inhomogeneous micro-structure has been seen in Transylvanian alluvial gold. The analyses revealed details on the fingerprint of geological gold deposits and also the main characteristics of ancient gold metallurgy procedures used by the Dacians: a relatively low temperature (lower than Au melting point) and hammering during heating to obtain an ingot through sintering. The use of the sintering procedure was proved for the spiraled bracelets and the Koson without monogram coins, a tradition starting in the Bronze Age in Transylvanian gold processing. The existence of micro-inclusions of Ta-minerals in alluvial gold was also detected, explaining Ta trace presence in the artifacts from the Pietroasa hoard. KW - Micro-SR-XRF KW - Micro-PIXE KW - Archaeometry KW - Gold KW - Romania PY - 2012 DO - https://doi.org/10.1039/c2ja30158j SN - 0267-9477 SN - 1364-5544 VL - 27 IS - 12 SP - 2076 EP - 2081 PB - Royal Society of Chemistry CY - London AN - OPUS4-26991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Niemeyer, B. A1 - Schwarzmaier, A. A1 - Radtke, Martin A1 - Hahn, Oliver T1 - Archaische Goldarbeiten aus Kleinasien in der Berliner Antikensammlung – Herstellungstechnik, Materialanalytik und der Fundkomplex »aus Ephesos« N2 - Ein Konvolut einzelner Schmuckstücke und die Goldbeigaben eines angeblichen Grabfundes wurden technologisch und analytisch untersucht. Die meisten Objekte sind Blecharbeiten, die aus einer Vielzahl von Einzelteilen mit metallischem Goldlot zusammengefügt und mit Granulation oder granulations-imitierendem Perl- oder Kerbdraht verziert wurden. Nur vier kleine Ohrringe sind massiv gegossen. Zwei Zierbleche dürften über Patrizen (Positivmodeln), die Deckel der Astragale in Matrizen (Negativmodeln) geformt worden sein. Alle Objekte wurden mit Synchrotron- und atmosphärischer Röntgenfluoreszenz analysiert. Die Daten zeigen das breite Spektrum an Goldlegierungen, die im 7./6. Jahrhundert v. Chr. in Kleinasien verarbeitet wurden: vom natürlichen Seifengold (Elektrum) bis zu geläutertem, fast reinem Gold. Eine Korrelation zwischen Goldqualität und Verarbeitungsmethode konnte nicht festgestellt werden. Sowohl hochreines als auch mit viel Silber und Kupfer legiertes Gold wurde zum Schmieden von Blecharbeiten, aber auch zum Massivguss verwendet. Aus der Goldfarbe kann wegen des Phänomens der oberflächlichen Goldanreicherung nicht auf eine Legierungszusammensetzung geschlossen werden. Der 1963 angekaufte Fundkomplex aus lydischen Metallarbeiten und ostionischen Salbgefäßen aus Ton dürfte einen Grabfund des frühen 6. Jahrhunderts v. Chr. darstellen, dessen Herkunft aus Ephesos jedoch nicht zu sichern ist. KW - Gold KW - Synchrotron KW - XRF PY - 2017 SN - 1866-7007 VL - 9 SP - 57 EP - 83 PB - RGZM. Archäologische Staatssammmlung München CY - München AN - OPUS4-42986 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Constantinescu, B. A1 - Vasilescu, A. A1 - Radtke, Martin A1 - Reinholz, Uwe T1 - Micro-SR-XRF studies for archaeological gold identification - the case of carpathian gold and romanian museal objects N2 - In the determination of the provenance of gold in archaeological artifacts, trace elements are more significant than the main components. Several minute fragments of natural Carpathian gold-placer and primary-and some very small (a few milligrams) fragments of archaeological items were studied using micro Synchrotron Radiation X-Ray Fluorescence (micro SR-XRF) at the BESSY Synchrotron Facility in Berlin, Germany. The goal of the study was to identify the trace elements characterizing Carpathian gold, looking especially at Sn, Sb, Pb and Te, and to determine if the gold in the archaeological items is native or refined. Applications to the authentication and provenance of nine Dacian gold bracelets, koson coins and two Bronze Age items are presented. KW - Gold KW - Provenance KW - Archeometry KW - Sy-XRF PY - 2010 DO - https://doi.org/10.1007/s00339-010-5624-1 SN - 0947-8396 VL - 99 IS - 2 SP - 383 EP - 389 PB - Springer CY - Berlin AN - OPUS4-21395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Constantinescu, B. A1 - Vasilescu, A. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Pacheco, C. A1 - Pichon, L. A1 - Oberländer-Târnoveanu, E. T1 - SR XRF and micro-PIXE studies on ancient metallurgy of thirteen Dacian gold bracelets N2 - A thorough microscopic investigation by SR XRF and micro-PIXE brings insight into the probable techniques used in the manufacture of thirteen Dacian gold bracelets, one of the most spectacular archaeological finds ever on the territory of Romania. KW - Micro-SR-XRF KW - Micro-PIXE KW - Archaeometry KW - Gold KW - Romania PY - 2012 DO - https://doi.org/10.1007/s00339-012-7306-7 SN - 0947-8396 VL - 109 IS - 2 SP - 395 EP - 402 PB - Springer CY - Berlin AN - OPUS4-26902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Heyn, A. T1 - Dynamic tafel factor adaption for the evaluation of instantaneous corrosion rates on zinc by using gel-type electrolytes N2 - The paper presents a new method for the determination and evaluation of tafel factors using gel-type electrolytes and electrochemical frequency modulation technique (EFM). This relatively new electrochemical method offers the possibility to determine both polarization resistances and tafel factors within one measurement and in short measuring intervals. Starting from a comprehensive parameter study it is shown that a direct relationship between the two values exists that can be described mathematically. This contribution presents the determined tafel factors for the system gel-type electrolyte/zinc and discusses their applicability and their limits. T2 - 19th Chemnitz Seminar on Materials Engineering – 19. Werkstofftechnisches Kolloquium CY - Chemnitz, Germany DA - 16.03.2017 KW - Gel-type electrolytes KW - Gelartige Elektrolyte KW - Zinc KW - Zink KW - Stern Geary constant KW - Stern-Geary-Konstante PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-394324 UR - http://iopscience.iop.org/article/10.1088/1757-899X/181/1/012021/pdf DO - https://doi.org/10.1088/1757-899X/181/1/012021 SN - 1757-899X SN - 1757-8981 VL - 181 IS - Conference 1 SP - Article UNSP 012021, 1 EP - 11 PB - IOP Publishing CY - Bristol, UK AN - OPUS4-39432 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Menzel, M. A1 - Scharf, O. A1 - Novak, S. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Hischenhuber, P. A1 - Buzanich, Günter A1 - Meyer, A. A1 - Lopez, V. A1 - McIntosh, K. A1 - Streli, C. A1 - Havrilla, G. A1 - Fittschen, U. T1 - Shading in TXRF: calculations and experimental validation using a color X-ray camera N2 - Absorption effects in total reflection X-ray fluorescence (TXRF) analysis are important to consider, especially if external calibration is to be applied. With a color X-ray camera (CXC), that enables spatially and energy resolved XRF analysis, the absorption of the primary beam was directly visualized for mL-droplets and an array of pL-droplets printed on a Si-wafer with drop-on-demand technology. As expected, deposits that are hit by the primary beam first shade subsequent droplets, leading to a diminished XRF signal. This shading effect was quantified with enhanced precision making use of sub-pixel analysis that improves the spatial resolution of the camera. The measured absorption was compared to simulated results using three different model calculations. It was found they match very well (average deviation < 10%). Thus errors in quantification due to absorption effects can be accounted for in a more accurate manner. KW - absorption KW - X-ray Fluorescence analysis PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-359000 DO - https://doi.org/10.1039/C5JA00127G IS - 10 SP - 2184 EP - 2193 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-35900 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hahn, Oliver A1 - Denker, A. A1 - Merchel, S. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Wolff, T. ED - Armbruster, B. ED - Eilbracht, H. ED - Hahn, Oliver ED - Heinrich-Tamaska, O. T1 - Zerstörungsfreie Analyse von Metallartefakten - Eine Fallstudie N2 - Die naturwissenschaftliche Analyse historischer Materialen ermöglicht die Beantwortung kulturhistorischer Fragestellungen, die mit kunsthistorischen oder archäologischen Ansätzen allein nicht zu leisten sind. In dieser Studie wurden sechs römische Münzen mit unterschiedlich stark ausgeprägten Korrosionsschichten an unbehandelten und polierten Stellen mit vier zerstörungsfreien analytischen Methoden untersucht: Hoch- und Niederenergie Protonen Induzierter Röntgenemission (HE-/PIXE), Synchrotronstrahlungsinduzierte-Röntgenfluoreszenzanalyse (SY-RFA) und Mikro-Röntgenfluoreszenzanalyse (Mikro-RFA) mit einem mobilen Gerät. Aufgrund von Unterschieden in den Messbedingungen und dem Einfluss der Patina-Schichten auf diese ergaben sich nur für wenige Elemente Übereinstimmungen in den quantitativen Daten. Zur Validierung zukünftiger Messkampagnen mit verschiedenen Methoden sind daher Vergleichstudien unerlässlich. N2 - Investigations of physical properties and chemical composition of ancient materials generate important data for answering culture-historical questions that cannot be solved by art historical and archaeological methods alone. This contribution reports on the analysis of six Roman coins, with different degrees of corrosion layers in parts that were not handled or polished, using four non-destructive methods: low-energy particle-induced X-ray emission (PIXE, 2 MeV), high-energy PIXE (68 MeV), μ-X-ray fluorescence (XRF) spectrometry with a portable device and synchrotron-radiation induced XRF. Because of differences in the conditions needed for measurement and the influence of the layers of patina on these measurements, there were few elements where the quantitative data were in agreement. Thus comparative analyses are essential to validate future measurement projects using different methods. KW - Zerstörungsfreie Prüfung KW - Protoneninduzierte Röntgenemission KW - Röntgenfluoreszenzanalyse KW - Non-destructive testing KW - Particle-induced X-ray emission KW - X-ray fluorescence analysis PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-385702 SN - 978-3-9816751-5-3 VL - Berlin studies of the ancient world, Band 35 SP - 117 EP - 137 PB - Edition Topoi CY - Berlin AN - OPUS4-38570 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hachmöller, O. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Aichler, M. A1 - Radtke, Martin A1 - Dietrich, D. A1 - Schwamborn, K. A1 - Lutz, L. A1 - Werner, M. A1 - Sperling, M. A1 - Walch, A. A1 - Karst, U. T1 - Elemental bioimaging and speciation analysis for the investigation of Wilsons disease using μXRF and XANES N2 - A liver biopsy specimen from a Wilson’s disease (WD) patient was analyzed by means of micro-X-ray fluorescence (mXRF) spectroscopy to determine the elemental distribution. First, bench-top mXRF was utilized for a coarse scan of the sample under laboratory conditions. The resulting distribution maps of copper and iron enabled the determination of a region of interest (ROI) for further analysis. In order to obtain more detailed elemental information, this ROI was analyzed by synchrotron radiation (SR)-based mXRF with a beam size of 4 mm offering a resolution at the cellular level. Distribution maps of additional elements to copper and iron like zinc and manganese were obtained due to a higher sensitivity of SR-mXRF. In addition to this, X-ray absorption near edge structure spectroscopy (XANES) was performed to identify the oxidation states of copper in WD. This speciation analysis indicated a mixture of copper(I) and copper(II) within the WD liver tissue. KW - progressive hepatolenticular degeneration KW - mXRF Micro-X-ray fluorescence spectroscopy KW - XANES X-ray absorption near edge structure spectroscopy PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-360811 DO - https://doi.org/10.1039/C6MT00001K SN - 1756-5901 SN - 1756-591X PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-36081 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de O. Primo, J. A1 - Horsth, D.F. A1 - de S. Correa, J. A1 - Das, A. A1 - Bittencourt, C. A1 - Umek, P. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Yusenko, Kirill A1 - Zanetta, C. A1 - Anaissi, F.J. T1 - Synthesis and Characterization of Ag/ZnO Nanoparticles for Bacteria Disinfection in Water N2 - n this study, two green synthesis routes were used for the synthesis of Ag/ZnO nanoparticles, using cassava starch as a simple and low-cost effective fuel and Aloe vera as a reducing and stabilizing agent. The Ag/ZnO nanoparticles were characterized and used for bacterial dis- infection of lake water contaminated with Escherichia coli (E. coli). Characterization indicated the formation of a face-centered cubic structure of metallic silver nanoparticles with no insertion of Ag into the ZnO hexagonal wurtzite structure. Physicochemical and bacteriological analyses described in “Standard Methods for the Examination of Water and Wastewater” were used to evaluate the efficiency of the treatment. In comparison to pure ZnO, the synthesized Ag/ZnO nanoparticles showed high efficiencies against Escherichia coli (E. coli) and general coliforms present in the lake water. These pathogens were absent after treatment using Ag/ZnO nanoparticles. The results indicate that Ag/ZnO nanoparticles synthesized via green chemistry are a promising candidate for the treatment of wastewaters contaminated by bacteria, due to their facile preparation, low-cost synthesis,and disinfection efficiency. KW - Synchrotron KW - BAMline PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-562440 DO - https://doi.org/10.3390/nano12101764 SN - 2079-4991 VL - 12 IS - 10 SP - 1 EP - 18 PB - MDPI CY - Basel AN - OPUS4-56244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grengg, C. A1 - Gluth, Gregor A1 - Mittermayr, F. A1 - Ukrainczyk, N. A1 - Bertmer, M. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Leis, A. A1 - Dietzel, M. T1 - Deterioration mechanism of alkali-activated materials in sulfuric acid and the influence of Cu: A micro-to-nano structural, elemental and stable isotopic multi-proxy study N2 - In this study, a multi-proxy approach combining 29Si, 27Al and 1H MAS-NMR, FEG-EPMA, XANES at the Cu K-edge and XRD analytics with hydrochemical tools such as ICP-OES analyses, oxygen-isotope signatures, and thermodynamic modelling was applied to K-silicate-activated metakaolin specimens - with and without CuSO4·5H2O addition - exposed to sulfuric acid at pH = 2 for 35 days. The results revealed a multistage deterioration mechanism governed by (i) acid diffusion, (ii) leaching of K-A-S-H, (iii) microstructural damage related to precipitation of expansive (K,Ca,Al)-sulfate-hydrate phases (iv) complete dissolution of the K-A-S-H framework, (v) and formation of silica gel in the outermost corroded regions. Copper ions were mainly located in layered spertiniite-chrysocolla-like phases in the as-cured materials. The results demonstrate an overall negative effect of Cu addition on chemical material durability, implying that the reported higher durability of Cu-doped AAM in biocorrosion environments can be best explained by bacteriostatic effects. KW - Alkali-activated materials KW - Acid resistance KW - Microbially induced corrosion KW - MIC PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520567 DO - https://doi.org/10.1016/j.cemconres.2021.106373 SN - 0008-8846 VL - 142 SP - 1 EP - 15 PB - Elsevier CY - Oxford AN - OPUS4-52056 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Fittschen, U. E. A. T1 - Shading Effects in SR-TXRF: Calculations and Experimental Visualization using a Color X-ray Camera T2 - Denver X-ray Conference CY - BIG SKY RESORT, BIG SKY, MONTANA, USA DA - 2014-07-28 PY - 2014 AN - OPUS4-32371 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lutz, C. A1 - Breuckmann, M. A1 - Hampel, S. A1 - Kreyenschmidt, M. A1 - Ke, X. A1 - Beuermann, S. A1 - Schafner, K. A1 - Turek, T. A1 - Kunz, U. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Fittschen, U. E. A. T1 - Characterization of Dimeric Vanadium Uptake and Species in Nafion™ and Novel Membranes from Vanadium Redox Flow Batteries Electrolytes N2 - A core component of energy storage systems like vanadium redox flow batteries (VRFB) is the polymer electrolyte membrane (PEM). In this work, the frequently used perfluorosulfonic-acid (PFSA) membrane Nafion™ 117 and a novel poly (vinylidene difluoride) (PVDF)-based Membrane are investigated. A well-known problem in VRFBs is the vanadium permeation through the membrane. The consequence of this so-called vanadium crossover is a severe loss of capacity. For a better understanding of vanadium transport in membranes, the uptake of vanadium ions from electrolytes containing Vdimer(IV–V) and for comparison also V(II), V(III), V(IV), and V(V) by both membranes was studied. UV/VIS spectroscopy, X-ray absorption near edge structure spectroscopy (XANES), total reflection X-ray fluorescence spectroscopy (TXRF), inductively coupled plasma optical emission spectrometry (ICP-OES), and micro X-ray fluorescence spectroscopy (microXRF) were used to determine the vanadium concentrations and the species inside the membrane. The results strongly support that Vdimer(IV–V), a dimer formed from V(IV) and V(V), enters the nanoscopic water-body of Nafion™ 117 as such. This is interesting, because as of now, only the individual ions V(IV) and V(V) were considered to be transported through the membrane. Additionally, it was found that the Vdimer(IV–V) dimer partly dissociates to the individual ions in the novel PVDF-based membrane. The Vdimer(IV–V) dimer concentration in Nafion™ was determined and compared to those of the other species. After three days of equilibration time, the concentration of the dimer is the lowest compared to the monomeric vanadium species. The concentration of vanadium in terms of the relative uptake λ = n(V)/n(SO3 ) are as follows: V(II) [λ = 0.155] > V(III) [λ = 0.137] > V(IV) [λ = 0.124] > V(V) [λ = 0.053] > Vdimer(IV–V) [λ = 0.039]. The results show that the Vdimer(IV–V) dimer Needs to be considered in addition to the other monomeric species to properly describe the transport of vanadium through Nafion™ in VRFBs. KW - MicroXRF KW - VRFB KW - PVDF-based membrane KW - UV/VIS KW - XANES KW - TXRF KW - ICP-OES PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530676 DO - https://doi.org/10.3390/membranes11080576 VL - 11 IS - 8 SP - 576 PB - MDPI AN - OPUS4-53067 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - C. Pardo Pérez, L. A1 - Arndt, A. A1 - Stojkovikj, S. A1 - Y. Ahmet, I. A1 - T. Arens,, J. A1 - Dattila, F. A1 - Wendt, R. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Davies, V. A1 - Höflich, K. A1 - Köhnen, E. A1 - Tockhorn, P. A1 - Golnak, R. A1 - Xiao, J. A1 - Schuck, G. A1 - Wollgarten, M. A1 - López, N. A1 - T. Mayer, M. T1 - Determining Structure-Activity Relationships in Oxide Derived CuSn Catalysts During CO2 Electroreduction Using X-Ray Spectroscopy N2 - The development of earth-abundant catalysts for selective electrochemical CO2 conversion is a central challenge. Cu-Sn bimetallic catalysts can yield selective CO2 reduction toward either CO or formate. This study presents oxide-derived Cu-Sn catalysts tunable for either product and seeks to understand the synergetic effects between Cu and Sn causing these selectivity trends. The materials undergo significant transformations under CO2 reduction conditions, and their dynamic bulk and surface structures are revealed by correlating observations from multiple methods—X-ray absorption spectroscopy for in situ study, and quasi in situ X-ray photoelectron spectroscopy for surface sensitivity. For both types of catalysts, Cu transforms to metallic Cu0 under reaction conditions. However, the Sn speciation and content differ significantly between the catalyst types: the CO-selective catalysts exhibit a surface Sn content of 13 at. % predominantly present as oxidized Sn, while the formate-selective catalysts display an Sn content of ≈70 at. % consisting of both metallic Sn0 and Sn oxide species. Density functional theory simulations suggest that Snδ+ sites weaken CO adsorption, thereby enhancing CO selectivity, while Sn0 sites hinder H adsorption and promote formate production. This study reveals the complex dependence of catalyst structure, composition, and speciation with electrochemical bias in bimetallic Cu catalysts. KW - Electrochemical CO2 conversion KW - Cu catalysts KW - X-ray absorption spectroscopy PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547116 DO - https://doi.org/10.1002/aenm.202103328 SN - 1614-6832 VL - 12 IS - 5 SP - 2103328 PB - Wiley-VCH GmbH AN - OPUS4-54711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radtke, Martin A1 - Rakotondrajoa, A. T1 - Machine learning based quantification of synchrotron radiation-induced X-ray fluorescence measurements - a case study N2 - In this work, we describe the use of artificial neural networks for the quantification of X-ray fluorescence measurements. The training data were generated using Monte Carlo simulation, which avoided the use of adapted reference materials. The extension of the available data set by means of an ANN to generate additional data was demonstrated. Particular emphasis was put on the comparability of simulated and experimental data and how the influence of deviations can be reduced. The search for the optimal hyperparameter, manual and automatic, is also described. For the presented case, we were able to train a network with a mean absolute error of 0.1 weight percent for the synthetic data and 0.7 weight percent for a set of experimental data obtained with certified reference materials. KW - Machine learning KW - BAMline KW - XRF KW - Synchrotron KW - Neural network PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-519008 DO - https://doi.org/10.1088/2632-2153/abc9fb SP - 1 EP - 16 PB - IOP Publishing AN - OPUS4-51900 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ha, Q. L. M. A1 - Armbruster, U. A1 - Atia, Hanan A1 - Lund, H. A1 - Agostini, G. A1 - Radnik, Jörg A1 - Vuong, H. T. A1 - Martin, A. T1 - Development of active and stable low nickel content catalysts for dry reforming of methane N2 - Methane dry reforming (DRM) was investigated over highly active Ni catalysts with low metal content (2.5wt%) supported on Mg-Al mixed oxide. The aim was to minimize carbon Deposition and metal sites agglomeration on the working catalyst which are known to cause catalyst deactivation. The solids were characterized using N2 adsorption, X-ray diffraction, temperature-programmed reduction, X-ray photoelectron spectroscopy, and UV-Vis diffuse reflectance spectroscopy. The results showed that MgO-Al2O3 solid solution phases are obtained when calcining Mg-Al hydrotalcite precursor in the temperature range of 550–800 °C. Such phases contribute to the high activity of catalysts with low Ni content even at low temperature (500 °C). Modifying the catalyst preparation with citric acid significantly slows the coking rate and reduces the size of large octahedrally coordinated NiO-like domains, which may easily agglomerate on the surface during DRM. The most effective Ni catalyst shows a stable DRM course over 60 h at high weight hourly space velocity with very low coke deposition. This is a promising result for considering such catalyst systems for further development of an industrial DRM technology. KW - Dry reforming of methane KW - Carbon dioxide KW - Ni PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-402904 DO - https://doi.org/10.3390/catal7050157 SN - 2073-4344 VL - 7 IS - 5 SP - 157, 1 EP - 157, 17 PB - MDPI AN - OPUS4-40290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steglich, P. A1 - Rabus, D. G. A1 - Sada, C. A1 - Paul, Martin A1 - Weller, Michael G. A1 - Mai, C. A1 - Mai, A. T1 - Silicon Photonic Micro-Ring Resonators for Chemical and Biological Sensing: A Tutorial N2 - Silicon photonic micro-ring resonators (MRR) developed on the silicon-on-insulator (SOI) platform, owing to their high sensitivity and small footprint, show great potential for many chemical and biological sensing applications such as label-free detection in environmental monitoring, biomedical engineering, and food analysis. In this tutorial,we provide the theoretical background and give design guidelines for SOI-based MRR as well as examples of surface functionalization procedures for label-free detection of molecules. After introducing the advantages and perspectives of MRR, fundamentals of MRR are described in detail, followed by an introduction to the fabrication methods, which are based on a complementary metal-oxide semiconductor (CMOS) technology. Optimization of MRR for chemical and biological sensing is provided, with special emphasis on the optimization of waveguide geometry. At this point, the difference between chemical bulk sensing and label-free surface sensing is explained, and definitions like waveguide sensitivity, ring sensitivity, overall sensitivity as well as the limit of detection (LoD) of MRR are introduced. Further, we show and explain chemical bulk sensing of sodium chloride (NaCl) in water and provide a recipe for label-free surface sensing. KW - Biosensors KW - Biophotonics KW - Chemosensor KW - Biosensor KW - Microresonator KW - Nanophotonics KW - Optical sensors KW - Photonic sensors KW - Optoelectronic KW - Ring resonator KW - Silicon photonics KW - Miniaturization KW - Lab-on-a-chip KW - Lab-on-chip KW - Waveguide KW - Surface chemistry KW - Silanization KW - Glutaraldehyde KW - Affinity immobilization KW - Antibody KW - Oriented immobilization KW - Real-time measurement PY - 2022 DO - https://doi.org/10.1109/JSEN.2021.3119547 SN - 1530-437X VL - 22 IS - 11 SP - 10089 EP - 10105 PB - IEEE AN - OPUS4-55147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bornemann-Pfeiffer, Martin A1 - Wolf, Jakob A1 - Meyer, Klas A1 - Kern, S. A1 - Angelone, D. A1 - Leonov, A. A1 - Cronin, L. A1 - Emmerling, Franziska T1 - Standardization and control of Grignard reactions in a universal chemical synthesis machine using online NMR T1 - Standardisierung und Kontrolle von Grignard-Reaktionen mittels Online-NMR in einer universellen chemischen Syntheseplattform N2 - A big problem with the chemistry literature is that it is not standardized with respect to precise operational parameters, and real time corrections are hard to make without expert knowledge. This lack of context means difficult reproducibility because many steps are ambiguous, and hence depend on tacit knowledge. Here we present the integration of online NMR into an automated chemical synthesis machine (CSM aka. “Chemputer” which is capable of small-molecule synthesis using a universal programming language) to allow automated analysis and adjustment of reactions on the fly. The system was validated and benchmarked by using Grignard reactions which were chosen due to their importance in synthesis. The system was monitored in real time using online-NMR, and spectra were measured continuously during the reactions. This shows that the synthesis being done in the Chemputer can be dynamically controlled in response to feedback optimizing the reaction conditions according to the user requirements. N2 - Ein Problem der chemischen Literatur ist die fehlende Standardisierung bezüglich genauer Bedingungen, auch Echtzeit-Korrekturen sind ohne Expertenwissen nur schwer möglich. Dieser Mangel an Details erschwert experimentelle Reproduzierbarkeit, da Schritte oft mehrdeutig sind und daher von implizitem Wissen abhängen. Hier präsentieren wir die Integration von Online-NMR Spektroskopie in eine automatisierte chemische Syntheseplattform (CSM aka. “Chemputer”, unter Verwendung einer universellen Programmiersprache zur Synthese kleiner Moleküle fähig), um eine automatisierte Analyse und Anpassung von Reaktionen im laufenden Betrieb zu ermöglichen. Das System wurde anhand von Grignard-Reaktionen, die aufgrund ihrer Bedeutung für die Synthese ausgewählt wurden, validiert und einem Härtetest unterzogen. Synthesen wurden in Echtzeit mit Online-NMR überwacht, und die Spektren wurden während der Reaktionen kontinuierlich aufgenommen und analysiert. Dies zeigt, dass der Chemputer dynamisch mittels einer Regelung kontrolliert werden kann, um die Reaktionsbedingungen entsprechend den Anforderungen des Benutzers zu optimieren. KW - Grignard reaction KW - NMR spectroscopy KW - Process analytical technology KW - Process control KW - Grignard-Reaktion KW - NMR-Spektroskopie KW - Prozessanalytik KW - Prozesskontrolle PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-531260 DO - https://doi.org/10.1002/anie.202106323 SN - 1521-3773 SN - 1433-7851 N1 - Bibliografische Angaben für die deutsche Version: Angewandte Chemie 2021, Jg. 133, S. 1–7, ISSN 0044-8249, ISSN 1521-3757, https://doi.org/10.1002/ange.202106323 - Bibliographic information for the German version: Angewandte Chemie 2021, vol. 133, p. 1–7, ISSN 0044-8249, ISSN 1521-3757, https://doi.org/10.1002/ange.202106323 VL - 60 IS - 43 SP - 1 EP - 6 PB - Wiley-VCH CY - Weinheim AN - OPUS4-53126 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steglich, P. A1 - Bondarenko, S. A1 - Mai, C. A1 - Paul, Martin A1 - Weller, Michael G. A1 - Mai, A. T1 - CMOS-Compatible Silicon Photonic Sensor for Refractive Index Sensing Using Local Back-Side Release N2 - Silicon photonic sensors are promising candidates for lab-on-a-chip solutions with versatile applications and scalable production prospects using complementary metal-oxide semiconductor (CMOS) fabrication methods. However, the widespread use has been hindered because the sensing area adjoins optical and electrical components making packaging and sensor handling challenging. In this work, a local back-side release of the photonic sensor is employed, enabling a separation of the sensing area from the rest of the chip. This approach allows preserving the compatibility of photonic integrated circuits in the front-end of line and metal interconnects in the back-end of line. The sensor is based on a micro-ring resonator and is fabricated on wafer-level using a CMOS technology. We revealed a ring resonator sensitivity for homogeneous sensing of 106 nm/RIU. KW - Photonic biosensor KW - Lab-on-a-chip KW - Ring resonator KW - Resonance wavelength shift KW - PIC technology KW - Back-side integration PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517139 DO - https://doi.org/10.1109/LPT.2020.3019114 VL - 32 IS - 19 SP - 1241 EP - 1244 PB - IEEE AN - OPUS4-51713 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steglich, P. A1 - Mai, C. A1 - Bondarenko, S. A1 - Paul, Martin A1 - Weller, Michael G. A1 - Schrader, S. A1 - Mai, A. T1 - BioPIC - Integration of Biosensors based on Photonic Integrated Circuits by Local-Backside Etching N2 - Silicon photonic sensors are promising candidates for lab-on-a-chip solutions with versatile applications and scalable production prospects using complementary metal-oxide semiconductor (CMOS) fabrication methods. However, the widespread use has been hindered because the sensing area adjoins optical and electrical components making packaging and sensor handling challenging. In this work, a local back-side release of the photonic sensor is employed, enabling a separation of the sensing area from the rest of the chip. This approach allows preserving the compatibility of photonic integrated circuits in the front-end of line and metal interconnects in the back-end of line. T2 - ATTRACT online Conference CY - Online meeting DA - 22.09.2020 KW - Silicon Photonics KW - Photonic Sensor KW - Photonic Integrated Circuits KW - Point-Of-Care-Diagnostics KW - CMOS KW - Microfluidics KW - Lab-on-a-chip KW - Ring resonator PY - 2020 UR - https://attract-eu.com/showroom/project/integration-of-biosensors-based-on-photonic-integrated-circuits-by-local-backside-etching-biopic/ SP - 1 EP - 5 AN - OPUS4-51735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Senges, Gene A1 - de Oliveira Guilherme Buzanich, Ana A1 - Lindič, Tilen A1 - Gully, Tyler A. A1 - Winter, Marlon A1 - Radtke, Martin A1 - Röder, Bettina A1 - Steinhauer, Simon A1 - Paulus, Beate A1 - Emmerling, Franziska A1 - Riedel, Sebastian T1 - Unravelling highly oxidized nickel centers in the anodic black film formed during the Simons process by in situ X-ray absorption near edge structure spectroscopy N2 - The electrofluorination after Simons has been used for the last century to produce everyday life materials. An in situ XANES investigation of the controversially debated black film apparent in the Simons process revealed high-valent nickel centers. KW - Synchrotron KW - BAMline KW - XANES PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-608366 DO - https://doi.org/10.1039/d3sc06081k SN - 2041-6520 VL - 15 IS - 12 SP - 4504 EP - 4509 PB - Royal Society of Chemistry (RSC) AN - OPUS4-60836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Steglich, P. A1 - Rabus, D. G. A1 - Sada, C. A1 - Paul, Martin A1 - Weller, Michael G. A1 - Mai, C. A1 - Mai, A. T1 - Silicon Photonic Micro-Ring Resonators for Chemical and Biological Sensing: A Tutorial N2 - Silicon photonic micro-ring resonators (MRR) developed on the silicon-on-insulator (SOI) platform, owing to their high sensitivity and small footprint, show great potential for many chemical and biological sensing applications such as label-free detection in environmental monitoring, biomedical engineering, and food analysis. In this tutorial, we provide the theoretical background and give design guidelines for SOI-based MRR as well as examples of surface functionalization procedures for label-free detection of molecules. After introducing the advantages and perspectives of MRR, fundamentals of MRR are described in detail, followed by an introduction to the fabrication methods, which are based on a complementary metal-oxide semiconductor (CMOS) technology. Optimization of MRR for chemical and biological sensing is provided, with special emphasis on the optimization of waveguide geometry. At this point, the difference between chemical bulk sensing and label-free surface sensing is explained, and definitions like waveguide sensitivity, ring sensitivity, overall sensitivity as well as the limit of detection (LoD) of MRR are introduced. Further, we show and explain chemical bulk sensing of sodium chloride (NaCl) in water and provide a recipe for label-free surface sensing. KW - Lab on a chip KW - Biosensor KW - Cmos KW - Silanization KW - Surface derivatization KW - Evanescent wave PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-529360 DO - https://doi.org/10.36227/techrxiv.14909901.v1 SP - 1 EP - 18 PB - IEEE CY - Piscataway Township AN - OPUS4-52936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cakir, Cafer Tufan A1 - Piotrowiak, T. A1 - Reinholz, Uwe A1 - Ludwig, A. A1 - Emmerling, Franziska A1 - Streli, C. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin T1 - Exploring the Depths of Corrosion: A Novel GE-XANES Technique for Investigating Compositionally Complex Alloys N2 - In this study, we propose the use of nondestructive, depth-resolved, element-specific characterization using grazing exit X-ray absorption near-edge structure spectroscopy (GE-XANES) to investigate the corrosion process in compositionally complex alloys (CCAs). By combining grazing exit X-ray fluorescence spectroscopy (GE-XRF) geometry and a pnCCD detector, we provide a scanning-free, nondestructive, depth-resolved analysis in a sub-micrometer depth range, which is especially relevant for layered materials, such as corroded CCAs. Our setup allows for spatial and energy-resolved measurements and directly extracts the desired fluorescence line, free from scattering events and other overlapping lines. We demonstrate the potential of our approach on a compositionally complex CrCoNi alloy and a layered reference sample with known composition and specific layer thickness. Our findings indicate that this new GE-XANES approach has exciting opportunities for studying surface catalysis and corrosion processes in real-world materials. KW - Degradation mechanisms KW - Grazin exit XANES KW - Depth resolved XANES KW - Compositional complex alloys KW - Corrosion PY - 2023 DO - https://doi.org/10.1021/acs.analchem.3c00404 VL - 95 SP - 4810 EP - 4818 PB - ACS Publications AN - OPUS4-57823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Polte, Jörg A1 - Herder, Martin A1 - Erler, Robert A1 - Rolf, Simone A1 - Fischer, A. A1 - Würth, Christian A1 - Thünemann, Andreas A1 - Kraehnert, R. A1 - Emmerling, Franziska T1 - Mechanistic insights into seeded growth processes of gold nanoparticles N2 - A facile approach for the synthesis of monodisperse gold nanoparticles with radii in the range of 7 to 20 nm is presented. Starting from monodisperse seeds with radii of 7 nm, produced in the first step, the addition of a defined amount of additional precursor material permits distinct size regulation and the realization of predicted nanoparticle sizes. These information were derived from ex- and in situ investigations by comprehensive small angle X-ray scattering (SAXS), X-ray absorption near edge structure (XANES) and UV-Vis data to obtain information on the physicochemical mechanisms. The obtained mechanisms can be transferred to other seeded growth processes. Compared to similar approaches, the presented synthesis route circumvents the use of different reducing or stabilizing agents. The size of resulting nanoparticles can be varied over a large size range presented for the first time without a measurable change in the shape, polydispersity or surface chemistry. Thus, the resulting nanoparticles are ideal candidates for size dependence investigations. KW - Gold nanoparticles KW - SAXS KW - XANES KW - Growth mechanism PY - 2010 DO - https://doi.org/10.1039/c0nr00541j SN - 2040-3364 SN - 2040-3372 VL - 2 IS - 11 SP - 2463 EP - 2469 PB - RSC Publ. CY - Cambridge AN - OPUS4-22346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kuhne, Maren A1 - Dippong, Martin A1 - Flemig, Sabine A1 - Hoffmann, Katrin A1 - Petsch, K. A1 - Schenk, J.A. A1 - Kunte, Hans-Jörg A1 - Schneider, Rudolf T1 - Comparative characterization of mAb producing hapten-specific hybridoma cells by flow cytometric analysis and ELISA N2 - A novel method that optimizes the screening for antibody-secreting hapten-specific hybridoma cells by using flow cytometry is described. Cell clones specific for five different haptens were analyzed. We selectively double stained and analyzed fixed hybridoma cells with fluorophore-labeled haptens to demonstrate the target-selectivity, and with a fluorophore-labeled anti-mouse IgG antibody to characterize the level of surface expression of membrane-bound IgGs. ELISA measurements with the supernatants of the individual hybridoma clones revealed that antibodies from those cells, which showed the highest fluorescence intensities in the flow cytometric analysis, also displayed the highest affinities for the target antigens. The fluorescence intensity of antibody-producing cells corresponded well with the produced antibodies' affinities toward their respective antigens. Immunohistochemical staining verified the successful double labeling of the cells. Our method makes it possible to perform a high-throughput screening for hybridoma cells, which have both an adequate IgG production rate and a high target affinity. KW - Immunization KW - Hapten KW - Monoclonal antibodies KW - Hybridoma KW - Flow cytometry KW - ELISA KW - Estradiol KW - Estrone KW - Digoxigenin KW - Zearalenone KW - Aflatoxin KW - CLSM PY - 2014 DO - https://doi.org/10.1016/j.jim.2014.07.004 SN - 0022-1759 SN - 1872-7905 VL - 413 SP - 45 EP - 56 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-32322 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiggenhauser, Herbert A1 - Samokrutov, A A1 - Mayer, K A1 - Krause, Martin A1 - Alekhin, S. G. A1 - Elkin, V T1 - Large aperture ultrasonic system for testing thick concrete structures N2 - A Large Aperture UltraSonic system (LAUS) has been designed and built for testing thick concrete structures. The scalable system consists of twelve ultrasonic units, each hosting 32 individual shear wave transducers with mechanical dry point contact (DPC) to the concrete surface. The twelve units are attached to the concrete surface using a vacuum case which holds them in place during operation. Each LAUS unit can be placed individually on the surface to achieve optimal ultrasonic condition, e.g. to avoid rebars. For the generation of vacuum, air pressure is supplied to each unit through an air hose. The twelve units define an aperture which is necessary for fast reconstruction of the subsurface structure. The well-known SAFT (Synthetic Aperture Focusing Technique) algorithm has been adopted to this situation, where the individual LAUS units form a linear aperture with not necessarily equidistant spacing between the units. The exact geometrical position of the units, which are individually marked with retroreflective labels, is determined using photographs and image processing. All transducers are synchronized and work either as transmitter or receiver. A full scan consists of 12 * 11 recordings, where each unit acts as transmitter once and all others as receivers. An electronic sub-unit on the back of the ultrasonic device holds the battery and handles data acquisition, synchronization and data communication. A computer is used as base unit which communicates with each LAUS unit for control and data acquisition, the synchronization is performed by a radio modem that uses a special algorithm similar to a digital PLL (phase locked loop). No wire connections are necessary between the units and the base system. The LAUS system is designed to investigate concrete structures with thicknesses in excess of 2 m, depending on the acoustic condition of the object under investigation. Highly reinforced concrete may have less penetration depth. The LAUS provides quasi real time imaging, once the transducers are put in place and the data has been acquired. First measurements on a foundation slab confirm, that the system can register ultrasonic echoes from the back wall at 4 m distance. KW - Ultrasound "Large Aperture" NDT Concrete PY - 2017 DO - https://doi.org/10.1061/(ASCE)IS.1943-555X.0000314 SN - 1076-0342 SN - 1943-555X VL - 23 IS - 1 SP - B4016004-1 EP - B4016004-9 PB - American Society of Civil Engineers (ASCE) CY - Reston, VA 20191-4400 USA AN - OPUS4-39372 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stadthaus, Meinhard A1 - Thomas, Hans-Martin A1 - Migoun, N.P. A1 - Gnusin, A.B. A1 - Baugatz, J. A1 - König, W. T1 - Sensitivity of penetrant and magnetic particle testing - Performance testing of detection media for penetrant and magnetic particle testing (PT and MT) N2 - Die Empfindlichkeit von Eindring- und Magnetpulverprüfungen (PT, MT) hängt unter anderem von der Eignung und der Qualität der Prüfmittel ab (für PT bezeichnet als Eindringsystem). Die Ermittlung der Empfindlichkeit erfolgt an Kontrollkörpern mit natürlichen und künstlichen Inhomogenitäten durch Ermittlung der Anzeigenerkennbarkeit als Maß für die Eignung. Die europäischen Normen spezifizieren die Anforderungen an die Prüfmittel für Typen-, Chargen- und Betriebsprüfungen nach pr EN ISO 3452-2 für PT und EN ISO 9934-2 für MT. Dieser Beitrag beschreibt die Ermittlung der Empfindlichkeit von Prüfmitteln sowie deren Qualifizierung bei der Typenprüfung. Die vorgeschlagenen Verfahren wurden durch experimentelle Untersuchungen validiert, bei denen ein Bildverarbeitungssystem zur Ermittlung der Anzeigenerkennbarkeit verwendet wurde. Im Hinblick auf die Qualifizierung der Prüfmittel wird die Zuverlässigkeit der Verfahren diskutiert. PY - 2004 DO - https://doi.org/10.3139/120.100591 SN - 0025-5300 VL - 46 IS - 6 SP - 320 EP - 326 PB - Carl Hanser Verlag CY - München AN - OPUS4-3574 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Kohlhoff, Harald A1 - Hüllmann, Dino A1 - Lilienthal, A.J. A1 - Kluge, Martin T1 - Bringing Mobile Robot Olfaction to the Next Dimension – UAV-based Remote Sensing of Gas Clouds and Source Localization N2 - This paper introduces a novel robotic platform for aerial remote gas sensing. Spectroscopic measurement methods for remote sensing of selected gases lend themselves for use on mini-copters, which offer a number of advantages for inspection and surveillance. No direct contact with the target gas is needed and thus the influence of the aerial platform on the measured gas plume can be kept to a minimum. This allows to overcome one of the major issues with gas-sensitive mini-copters. On the other hand, remote gas sensors, most prominently Tunable Diode Laser Absorption Spectroscopy (TDLAS) sensors have been too bulky given the payload and energy restrictions of mini-copters. Here, we introduce and present the Unmanned Aerial Vehicle for Remote Gas Sensing (UAV-REGAS), which combines a novel lightweight TDLAS sensor with a 3-axis aerial stabilization gimbal for aiming on a versatile hexacopter. The proposed system can be deployed in scenarios that cannot be addressed by currently available robots and thus constitutes a significant step forward for the field of Mobile Robot Olfaction (MRO). It enables tomographic reconstruction of gas plumes and a localization of gas sources. We also present first results showing the gas sensing and aiming capabilities under realistic conditions. T2 - IEEE International Conference on Robotics and Automation (ICRA) CY - Singapore DA - 29.05.2017 KW - Tunable Diode Laser Absorption Spectroscopy (TDLAS) KW - 3-axis gimbal KW - Mobile Robot Olfaction KW - Tomographic reconstruction of gas plumes KW - Localization of gas sources KW - Aerial platform PY - 2017 SN - 978-1-5090-4632-4 SP - 3910 EP - 3916 PB - IEEE AN - OPUS4-40545 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fittschen, U.E.A. A1 - Menzel, M. A1 - Scharf, O. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Buzanich, Günter A1 - Lopez, V.M. A1 - McIntosh, K. A1 - Streli, C. A1 - Havrilla, G.J. T1 - Observation of X-ray shadings in synchrotron radiation-total reflection X-ray fluorescence using a color X-ray camera N2 - Absorption effects and the impact of specimen shape on TXRF analysis has been discussed intensively. Model calculations indicated that ring shaped specimens should give better results in terms of higher counts per mass signals than filled rectangle or circle shaped specimens. One major reason for the difference in signal is shading effects. Full field micro-XRF with a color X-ray camera (CXC) was used to investigate shading, which occurs when working with small angles of excitation as in TXRF. The device allows monitoring the illuminated parts of the sample and the shaded parts at the same time. It is expected that sample material hit first by the primary beam shade material behind it. Using the CXC shading could be directly visualized for the high concentration specimens. In order to compare the experimental results with calculation of the shading effect the generation of controlled specimens is crucial. This was achieved by 'drop on demand' technology. It allows generating uniform, microscopic deposits of elements. The experimentally measured shadings match well with those expected from calculation. KW - TXRF KW - Full field micro-XRF KW - Color X-ray camera PY - 2014 DO - https://doi.org/10.1016/j.sab.2014.06.025 SN - 0584-8547 SN - 0038-6987 VL - 99 SP - 179 EP - 184 PB - Elsevier CY - Amsterdam AN - OPUS4-31180 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cabral, A.R. A1 - Radtke, Martin A1 - Munnik, F. A1 - Lehmann, B. A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Tupinambá, M. A1 - Kwitko-Ribeiro, R. T1 - Iodine in alluvial platinum-palladium nuggets: evidence for biogenic precious-metal fixation N2 - Synchrotron radiation-induced X-ray fluorescence (SR-XRF) spectrometry was applied to determine iodine concentrations in alluvial Pt–Pd aggregates with delicate morphological features from Córrego Bom Sucesso, Minas Gerais, Brazil. The millimetre-sized botryoidal and rod-shaped grains of alluvial Pt–Pd–Hg intermetallic compounds have surprisingly high concentrations of iodine, in the range from 10 to ~ 120 μg/g. Because iodine is a strongly biophile element, known to be enriched in peatlands and plant remains in soils by microbial activity, its concentration in the Pt–Pd nuggets suggests biogenic precious-metal fixation in the aqueous alluvial milieu. Biogenic and inorganic processes, such as bioreduction and electrochemical metal accretion, could mutually have contributed to the growth of nanoparticles, formed on organic templates, to millimetric Pt–Pd nuggets. KW - Lodine KW - Pt-Pd nuggets KW - Córrego Bom Sucesso KW - Minas Gerais KW - Brazil PY - 2011 DO - https://doi.org/10.1016/j.chemgeo.2010.12.003 SN - 0009-2541 SN - 1872-6836 VL - 281 IS - 1-2 SP - 125 EP - 132 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-23174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lahiri, D. A1 - Sharma, S.M. A1 - Verma, A.K. A1 - Vishwanadh, B. A1 - Dey, G.K. A1 - Schumacher, G. A1 - Scherb, T. A1 - Riesemeier, Heinrich A1 - Reinholz, Uwe A1 - Radtke, Martin A1 - Banerjee, S. T1 - Investigation of short-range structural order in Zr69.5Cu12Ni11Al7.5 and Zr41.5Ti41.5Ni17 glasses, using X-ray absorption spectroscopy and ab initio molecular dynamics simulations N2 - Short-range order has been investigated in Zr69.5Cu12Ni11Al7.5 and Zr41.5Ti41.5Ni17 metallic glasses using X-ray absorption spectroscopy and ab initio molecular dynamics simulations. While both of these alloys are good glass formers, there is a difference in their glass-forming abilities (Zr41.5Ti41.5Ni17 > Zr69.5Cu12Ni11Al7.5). This difference is explained by inciting the relative importance of strong chemical order, icosahedral content, cluster symmetry and configuration diversity. KW - Multi-component alloy KW - Glass-forming ability KW - XAFS KW - Local structure KW - AIMD simulation PY - 2014 DO - https://doi.org/10.1107/S1600577514017792 SN - 0909-0495 SN - 1600-5775 VL - 21 IS - 6 SP - 1296 EP - 1304 PB - Blackwell Publishing CY - Oxford AN - OPUS4-31837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kulow, Anicó A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe A1 - Emmerling, Franziska A1 - Hampel, S. A1 - Fittschen, U.E.A. A1 - Streli, C. A1 - Radtke, Martin T1 - Comparison of three reconstruction methods based on deconvolution, iterative algorithm and neural network for X-ray fluorescence imaging with coded apertures N2 - X-ray imaging methods are used in many fields of research, as they allow a non-destructive Investigation of the elemental content of various samples. As for every imaging method, for X-ray imaging the optics are of crucial importance. However, these optics can be very expensive and laborious to build, as the requirements on surface roughness and precision are extremely high. Angles of reflection and refraction are often in the range of a few mrad, making a compact design hard to achieve. In this work we present a possibility to simplify X-ray imaging. We have adapted the coded aperture method, a high energy radiation imaging method that has its origins in astrophysics, to full field X-ray fluorescence imaging. In coded aperture imaging, an object is projected through a known mask, the coded aperture, onto an area sensitive detector. The resulting image consists of overlapping projections of the object and a reconstruction step is necessary to obtain the information from the recorded image. We recorded fluorescence images of different samples with an energy-dispersive 2D detector (pnCCD) and investigated different reconstruction methods. With a small coded aperture with 12 holes we could significantly increase the count rate compared to measurements with a straight polycapillary optic. We show that the reconstruction of two different samples is possible with a deconvolution approach, an iterative algorithm and a neural network. These results demonstrate that X-ray fluorescence imaging with coded apertures has the potential to deliver good results without scanning and with an improved count rate, so that measurement times can be shortened compared to established methods. KW - X-ray fluorescence imaging KW - Coded apertures KW - Imaging KW - Elemental mapping KW - Image reconstruction PY - 2020 DO - https://doi.org/10.1039/d0ja00146e VL - 35 IS - 7 SP - 1423 EP - 1434 PB - Royal Society of Chemistry CY - United Kingdom AN - OPUS4-51518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -