TY - CONF A1 - Radtke, Martin A1 - Cakir, Cafer Tufan A1 - de Oliveira Guilherme Buzanich, Ana T1 - Getting more efficient – The use of Bayesian optimization and Gaussian processes at the BAMline N2 - For more than 20 years, BAM is operating the BAMline at the synchrotron BESSY II in Berlin Adlershof. During this time, the complexity of the setup and the amount of data generated have multiplied. To increase the effectiveness and in preparation for BESSY III, algorithms from the field of machine learning are increasingly used. After a short introduction to BO and GP, the first example is the automatic alignment of our double multilayer monochromator (DMM). The second example is the optimization of measurement time in XRF scanning. T2 - SNI2022 conference CY - Berlin, Germany DA - 05.09.2022 KW - Artificial Inelligence KW - Machine Learning KW - Bayesian Statistics KW - Gaussian process KW - X-ray fluorescence KW - BAMline PY - 2022 AN - OPUS4-56255 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Buzanich, Ana A1 - Cakir, C.T. T1 - Enhancing efficiency at bamline: employing data science and machine learning for x-ray research N2 - This talk discusses how data science and machine learning techniques are being applied at the BAM Federal Institute for Materials Research and Testing to enhance efficiency and automation at the BAMLine synchrotron facility. The methods presented include Gaussian processes and Bayesian optimization for beamline adjustment and optimization of X-ray measurements. These statistical techniques allow automated alignment of beamline components and active learning scanning to reduce measurement time. Additional machine learning methods covered are neural networks for quantification of X-ray fluorescence (XRF) data and decoding coded apertures. T2 - 17th International Work-Conference on Artificial Neural Networks (IWANN2023) CY - Ponta Delgada, Portugal DA - 19.06.2023 KW - Bayesian Optimization KW - Gaussian Process KW - BAMline PY - 2023 AN - OPUS4-58605 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Guilherme Buzanich, Ana A1 - Cakir, C.T. A1 - Yusenko, Kirill A1 - Emmerling, Franziska T1 - Insights into materials with hard x-rays: capabilities of the bamline N2 - This contribution provides an overview of the BAMline synchrotron radiation beamline, which specializes in hard X-ray spectroscopy techniques for materials research. The BAMline offers X-ray absorption spectroscopy (XAS), x-ray fluorescence spectroscopy (XRF), and tomography to study materials' electronic structure, chemical composition, and structure. Key capabilities include standard and dispersive XAS for electronic structure, micro-XRF for elemental mapping, coded aperture imaging, and depth-resolved grazing exit XAS. The BAMline enables in situ characterization during materials synthesis and functions for energy, catalysis, corrosion, biology, and cultural heritage applications. Ongoing developments like the implementation of machine learning techniques for experiment optimization and data analysis will be discussed. For instance, Bayesian optimization is being used to improve beamline alignment and scanning. An outlook to the future, where the BAMline will continue pioneering dynamic and multi-scale characterization, aided by advanced data science methods, to provide unique insights into materials research, will be given. T2 - μ-XRF at Elettra 2.0: challenges and opportunities CY - Trieste, Italy DA - 11.09.2023 KW - Synchrotron KW - XRF KW - XANES KW - Bayes PY - 2023 AN - OPUS4-58607 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - El-Hasan, T. A1 - Szczerba, Wojciech A1 - Buzanich, Günter A1 - Radtke, Martin A1 - Riesemeier, Heinrich A1 - Kersten, M. T1 - Cr(VI)/Cr(III) and As(V)/As(III) ratio assessments in Jordanian spent oil shale produced by aerobic combustion and anaerobic pyrolysis N2 - With the increase in the awareness of the public in the environmental impact of oil shale utilization, it is of interest to reveal the mobility of potentially toxic trace elements in spent oil shale. Therefore, the Cr and As oxidation state in a representative Jordanian oil shale sample from the El-Lajjoun area were investigated upon different lab-scale furnace treatments. The anaerobic pyrolysis was performed in a retort flushed by nitrogen gas at temperatures in between 600 and 800 °C (pyrolytic oil shale, POS). The aerobic combustion was simply performed in porcelain cups heated in a muffle furnace for 4 h at temperatures in between 700 and 1000 °C (burned oil shale, BOS). The high loss-on-ignition in the BOS samples of up to 370 g kg–1 results from both calcium carbonate and organic carbon degradation. The LOI leads to enrichment in the Cr concentrations from 480 mg kg–1 in the original oil shale up to 675 mg kg–1 in the ≥850 °C BOS samples. Arsenic concentrations were not much elevated beyond that in the average shale standard (13 mg kg–1). Synchrotron-based X-ray absorption near-edge structure (XANES) analysis revealed that within the original oil shale the oxidation states of Cr and As were lower than after its aerobic combustion. Cr(VI) increased from 0% in the untreated or pyrolyzed oil shale up to 60% in the BOS ash combusted at 850 °C, while As(V) increased from 64% in the original oil shale up to 100% in the BOS ash at 700 °C. No Cr was released from original oil shale and POS products by the European compliance leaching test CEN/TC 292 EN 12457-1 (1:2 solid/water ratio, 24 h shaking), whereas leachates from BOS samples showed Cr release in the order of one mmol L–1. The leachable Cr content is dominated by chromate as revealed by catalytic adsorptive stripping voltammetry (CAdSV) which could cause harmful contamination of surface and groundwater in the semiarid environment of Jordan. KW - Trace-elements KW - Fly-ash KW - Speciation KW - Chromium KW - Sediments KW - Behavior KW - Metals KW - Xanes KW - Cr KW - Transformation PY - 2011 DO - https://doi.org/10.1021/es200695e SN - 0013-936X SN - 1520-5851 VL - 45 IS - 22 SP - 9799 EP - 9805 PB - ACS Publ. CY - Washington, DC AN - OPUS4-25290 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 - Polte, Jörg A1 - Kraehnert, R. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Thünemann, Andreas A1 - Emmerling, Franziska T1 - New insights of the nucleation and growth process of gold nanoparticles via in situ coupling of SAXS and XANES N2 - Although metallic nanoparticles play an important role in the area of nanotechnology, a coherent mechanistic explanation for the evolution of the particles during their chemical synthesis has not yet been provided in many cases. To gain a profound understanding of the growth mechanism of colloidal nanoparticles, new approaches using Small Angle X-Ray Scattering (SAXS) combined with X-ray absorption near-edge structure (XANES) are presented. This combination allows for insights into two prominent syntheses routes of gold nanoparticles (GNP): The 'slow' reaction using sodium citrate (30-90 min) as a reducing agent and the 'fast' reaction employing NaBH4 (within few seconds). In the first case data derived with the coupled XANES and SAXS suggests a four-step particle formation mechanism. For the second system a time resolution in the order of 100-200 ms was achieved by coupling a common laboratory SAXS instrument with a microstructured mixer, which allows data acquisition in a continuous-flow mode. The results indicate a coalescence driven growth process. Based on the capabilities to deduce the size, number and polydispersity of the particles, the results of both methods enable the development of mechanistic schemes explaining the different phases of particle formation and growth, thus providing a basis for improved control over the synthesis processes. KW - SAXS KW - XANES KW - Nanoparticle formation PY - 2010 DO - https://doi.org/10.1088/1742-6596/247/1/012051 SN - 1742-6588 SN - 1742-6596 VL - 247 IS - 1 SP - 012051-1 - 012051-10 PB - IOP Publ. CY - Bristol, UK AN - OPUS4-22684 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Scharf, Oliver A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Buzanich, Günter A1 - Bjeoumikhov, A. A1 - Gubzhokov, Renat A1 - Wedell, R. A1 - Soltau, H. A1 - Ihle, S. A1 - Ordavo, I. A1 - Langhoff, N. T1 - The colour X-ray camera: Basics, Applications and Perspectives T2 - 21st International Congress on X-ray Optics and Microanalysis (ICXOM21) CY - Campinas, Brazil DA - 2011-09-05 PY - 2011 AN - OPUS4-24024 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Scharf, O. A1 - Bjeoumikova, S. A1 - Wedell, R. A1 - Soltau, H. A1 - Ordavo, I. A1 - Langhoff, N. A1 - Buzanich, Günter A1 - Reinholz, Uwe A1 - Gubzhokov, Renat A1 - Kuehbacher, M. A1 - Giere, P. A1 - Riesemeier, Heinrich T1 - Non-invasive spatial scanning for iron and calcium in the enamel of a red toothed shrew, Sorex araneus (Soricidae, Lipotyphla) T2 - 85th Annual Conference of the German Society of Mammalogy CY - Luxembourg City, Luxembourg DA - 2011-09-13 PY - 2011 AN - OPUS4-24025 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Scharf, Oliver A1 - Buzanich, Günter A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Arkadiev, V. A1 - Wedell, R. A1 - Bjeoumikhov, A. A1 - Langhoff, N. A1 - Ihle, S. A1 - Soltau, H. A1 - Ordavo, I. T1 - The Colour X-Ray Camera: Basics, Applications and Perspectives T2 - Third Joint BER II and Bessy II User`s Meeting CY - Berlin, Germany DA - 2011-11-30 PY - 2011 AN - OPUS4-25269 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - The Color X-Ray Camera: Basics, Applications and Perspectives T2 - Third Joint BER II and BESSY II Users´ Meeting CY - Berlin, Germany DA - 2011-11-30 PY - 2011 AN - OPUS4-25127 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Materialforschung an der BAMline T2 - DGM-Fachausschuss Werkstoffcharakterisierung mit Strahllinien CY - Berlin, Germany DA - 2011-05-27 PY - 2011 AN - OPUS4-24026 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Scharf, Oliver A1 - Reinholz, Uwe A1 - Buzanich, Günter A1 - Riesemeier, Heinrich A1 - Langhoff, N. A1 - Gubzhokov, R. A1 - Bjeoumikova, S. A1 - Wedell, R. A1 - Ihle, S. A1 - Soltau, H. T1 - X-ray camera with high energy and spital resolution: Sterography with a colour X-ray camera T2 - European Conference on X-ray Spectrometry CY - Figueira da Foz, Portugal DA - 2010-06-20 PY - 2010 AN - OPUS4-21205 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Cabral, A. R. A1 - Lehmann, B. A1 - Munnik, F. T1 - Spatially-resolved detection of iodine in natural plantinum-palladium nuggets: a comparison of PIXE and XRF T2 - European Conference on X-ray Spectrometry CY - Figueira da Foz, Portugal DA - 2010-06-20 PY - 2010 AN - OPUS4-21073 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Munnik, F. A1 - Lehmann, B. A1 - Cabral, A. R. T1 - Spatially-resolved detection of iodine in natural platinum-palladium nuggets: a comparison of PIXE and XRF T2 - European Conference on X-ray Spectrometry CY - Figueira da Foz, Portugal DA - 2010-06-20 PY - 2010 AN - OPUS4-21201 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich T1 - Synchrotron radiation induced X-ray fluorescence for the characterization of ancient gold objects KW - Gold KW - Hiddensee treasure KW - Nebra sky disc KW - Non-destructive testing KW - Silver point drawings KW - Synchrotron KW - X-ray fluorescence KW - Or KW - Trésor d´Hiddensee KW - Disque déleste de Nebra KW - Analyse non-destructive KW - Dessins à pointe d´argent KW - Synchrotron KW - Fluorescence à rayons X PY - 2009 SN - 0399-1237 VL - 33 SP - 39 EP - 44 PB - Groupe CY - Rennes AN - OPUS4-23219 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Polte, Jörg A1 - Emmerling, Franziska A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Thünemann, Andreas T1 - Real-time monitoring of copolymer stabilized growing gold nanoparticles N2 - A great challenge in the production of nanoparticles with defined sizes and properties is to control their growth in situ. We developed a dedicated combined small-angle X-ray scattering (SAXS) and X-ray absorption spectroscopy (XAS) setup to monitor nanoparticle formation in solution. The capabilities of simultaneously deriving particle sizes and oxidation states of atoms/ions are illustrated for the formation of spherical gold nanoparticles by the reduction of hydrogen tetrachloroaureate (HAuCl4). Particles with initial radii of 4.60 ± 0.10 nm and final radii of 5.67 ± 0.10 nm were produced in a levitated droplet with a volume of 4 µL. An ethylene oxide/propylene oxide triblock copolymer PEO-PPO-PEO (Pluronic F-127) functions as reducing agent and colloidal stabilizer. XANES shows in situ how the gold was reduced in the droplet from Au(III) to Au(0), and simultaneously SAXS recorded the size distribution of the formed nanoparticles. It is shown that the final particle number is reached quickly. Thereafter, only the particles’ sizes increase. Comparison of XANES and SAXS shows that the quantity of Au(0) is higher than the quantity of gold located in the nanoparticles while the particles are growing. Finally, all the Au(0) is found in the nanoparticles. We tentatively attribute this finding to the pseudo crown ether effect of the polymer surfactant that kinetically stabilizes gold atoms when formed from gold ions within their protecting cavity. A simple “burst” mechanism for the gold nanoparticle formation is the consequence. The possibility of an inhomogeneous particles structure with an enhanced density near the particle surface is discussed. PY - 2010 DO - https://doi.org/10.1021/la903829q SN - 0743-7463 SN - 1520-5827 VL - 26 IS - 8 SP - 5889 EP - 5894 PB - American Chemical Society CY - Washington, DC AN - OPUS4-21223 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich T1 - Characterization of precious metal objects with SRXRF at the Bamline T2 - Synchrotron Radiation in Art & Archaeology (SR2A-2010) CY - Amsterdam, Netherlands DA - 2010-11-07 PY - 2010 AN - OPUS4-21244 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Strub, E. A1 - Born, H. T1 - Neues vom Berliner Goldhut: Analyse mit Sy-RFA T2 - Deutsche Tagung für Forschung mit Synchrotronstrahlung, Neutronen und Ionenstrahlen, SNI 2010 CY - Berlin, Germany DA - 2010-02-24 PY - 2010 AN - OPUS4-20097 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Röntgenfluoreszenzanalyse mit Synchrotronstrahlung an der Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin T2 - Seminar: "Strahlenphysikalische Anwendungen in Technik und Medizin" CY - Vienna, Austria DA - 2011-01-19 PY - 2011 AN - OPUS4-23265 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Von der Bronzezeit ins 21. Jahrhundert - Materialcharakterisierung mit SyXRF an der BAMline T2 - 17. Sitzung des Fachausschusses Zerstörungsfreie Materialcharakterisierung, DGZFP CY - Berlin, Germany DA - 2009-11-10 PY - 2009 AN - OPUS4-20772 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -