TY - JOUR A1 - Guerra, M. F. A1 - Calligaro, T. A1 - Radtke, Martin A1 - Reiche, I. A1 - Riesemeier, Heinrich T1 - Fingerprinting ancient gold by measuring Pt with spatially resolved high energy Sy-XRF N2 - Trace elements of ancient gold such as Pt, give fundamental information on the circulation of the metal in the past. In the case of objects from the cultural heritage, the determination of trace elements requires non-destructive point analysis in general. These conditions and the need of good detection limits restrain the number of applicable analytical techniques. After the development of a PIXE set-up with a selective Cu or Zn filter of 75 µm and of a PIXE-XRF set-up using a primary target of As, we tested the possibilities of spatially resolved Sy-XRF to determine Pt in gold alloys. With a Zn filter, PIXE showed a detection limit of 1000 ppm in gold while PIXE-XRF lowers this detection limit down to 80 ppm. This last value being constrained by the resonant Raman effect produced on gold. In order to improve the detection limit of Pt keeping the non-destructiveness and access to point analysis, we developed an analytical protocol for XRF with synchrotron radiation at BESSY II, using the BAMline set-up. The L-lines of Pt were excited by a beam of energy above and below 11.564 keV and measured using a Si(Li) detector with a 50 µm Cu filter. A µ-beam of 100–250 µm2 was used according to the size of the sample. The determination of the Pt content in the samples was carried out by Monte-Carlo simulation and subtraction of Au and Pt spectra obtained on pure standards. The limit of detection for Pt of 20 ppm was determined by using certified standards. The detection limits of a small set of other characteristic elements of gold were also measured using an incident energy of 33 keV. KW - PIXE-XRF KW - Sy-XRF KW - Pt KW - Ancient gold KW - Fingerprinting PY - 2005 DO - https://doi.org/10.1016/j.nimb.2005.06.150 SN - 0168-583X SN - 1872-9584 VL - 240 IS - 1-2 SP - 505 EP - 511 PB - Elsevier CY - Amsterdam AN - OPUS4-14236 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 - JOUR A1 - Scharf, Oliver A1 - Ihle, S. A1 - Ordavo, I. A1 - Arkadiev, V. A1 - Bjeoumikhov, A. A1 - Bjeoumikhova, S. A1 - Buzanich, Günter A1 - Gubzhokov, R. A1 - Günther, A. A1 - Hartmann, R. A1 - Kühbacher, M. A1 - Lang, M. A1 - Langhoff, N. A1 - Liebel, A. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Soltau, H. A1 - Strüder, L. A1 - Thünemann, Andreas A1 - Wedell, R. T1 - Compact pnCCD-based X-ray camera with high spatial and energy resolution: a color X-ray camera N2 - For many applications there is a requirement for nondestructive analytical investigation of the elemental distribution in a sample. With the improvement of X-ray optics and spectroscopic X-ray imagers, full field X-ray fluorescence (FF-XRF) methods are feasible. A new device for high-resolution X-ray imaging, an energy and spatial resolving X-ray camera, is presented. The basic idea behind this so-called 'color X-ray camera' (CXC) is to combine an energy dispersive array detector for X-rays, in this case a pnCCD, with polycapillary optics. Imaging is achieved using multiframe recording of the energy and the point of impact of single photons. The camera was tested using a laboratory 30 µm microfocus X-ray tube and synchrotron radiation from BESSY II at the BAMline facility. These experiments demonstrate the suitability of the camera for X-ray fluorescence analytics. The camera simultaneously records 69696 spectra with an energy resolution of 152 eV for manganese Kα with a spatial resolution of 50 µm over an imaging area of 12.7 × 12.7 mm². It is sensitive to photons in the energy region between 3 and 40 keV, limited by a 50 µm beryllium window, and the sensitive thickness of 450 µm of the chip. Online preview of the sample is possible as the software updates the sums of the counts for certain energy channel ranges during the measurement and displays 2-D false-color maps as well as spectra of selected regions. The complete data cube of 264 × 264 spectra is saved for further qualitative and quantitative processing. KW - Color X-ray camera KW - X-ray fluorescence KW - pnCCD KW - Polycapillary optic KW - Synchrotron radiation PY - 2011 DO - https://doi.org/10.1021/ac102811p SN - 0003-2700 SN - 1520-6882 VL - 83 IS - 7 SP - 2532 EP - 2538 PB - American Chemical Society CY - Washington, DC AN - OPUS4-23948 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 - CONF A1 - Radtke, Martin T1 - Artificial intelligence for spectroscopy examples from BAMline N2 - Various applications for artificial intelligence in the context of spectroscopy will be presented. in particular, examples from bamline will be featured. After a short introduction to synchrotron radiation, artificial intelligence algorithms for the quantification of X-ray fluorescence measurement are discussed. In the second example, information retrieval by natural language processing is reviewed. As a last example the reconstruction of measurements with the X-ray color camera and coded apertures is presented. T2 - Seminar Strahlenphysikalische Anwendungen in Technik und Medizin CY - ATi Wien, Austria DA - 22.01.2020 KW - Machine learning KW - Natural language processing KW - Neural networks KW - Synchrotron KW - BAMline PY - 2020 AN - OPUS4-51891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aldrabee, A. A1 - Wriekat, A. A1 - Abu Saleem, K. A1 - Radtke, Martin T1 - Non-destructive SR-XRF analysis of ancient Mamluk-Ayyubid glazed pottery fragments from Karak Castle, Jordan N2 - Sixteen Ayyubid-Mamluk glazed pottery sherds were analyzed in order to identify and characterize the elemental composition to determine their provenance. The tested sherds were collected from the historical site of Karak Castle, southern Jordan. Chemical analysis for the sixteen samples has been carried out using Synchrotron Radiation X-ray Fluorescence Spectrometry (SR-XRF) Technique. Furthermore, the semiquantitative analysis of the elements Fe – Cu – Zn – Br – Rb – Sr – Y – Zr – Nb – Mo – Pd – Ag – Cd and Pb has been performed for the samples based on Principal Component Analysis (PCA) and hierarchical Cluster Analysis with Bray-Curtis in order to define grouping of different glazed pottery by obtaining information on their similarity and clustering. The results of chemical analysis provided persuasive evidence that the Karak Castle pottery sherds have at least three different sources of provenance. KW - BAMline KW - Karak Castle KW - Synchrotron KW - XRF PY - 2015 VL - 8 IS - 3 SP - 157 EP - 163 AN - OPUS4-43489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Getting more efficient – The use of Bayesian optimization and Gaussian processes at the BAMline N2 - The BAMline, a beamline for material science research at BESSY II, has been operated by the Bundesanstalt für Materialforschung und -prüfung for over two decades. In the last few years, Bayesian optimization (BO) with Gaussian processes (GP) has been introduced as a transformative method in this setting. This contribution highlights the integration and impact of BO and GP in refining BAMline operations. We will explore the impact of integrating Bayesian methods, especially when combined with Gaussian processes, on the operational efficiency of the BAMline. Our discussion commences with an overview of the fundamental concepts of active learning and optimization. This is followed by an in-depth analysis of specific case studies, drawing on our direct experience with these innovative methods. For this our focus is on three key applications: Alignment of Optical Elements (DCM and DMM): The implementation of Bayesian optimization using Gaussian processes has revolutionized the alignment process for the Double Crystal Monochromator (DCM) and the Double Multilayer Monochromator (DMM). This approach greatly reduced manual effort and enhanced the efficiency and effectiveness of the alignment procedure. Optimal Spot Selection for Spatial Mapping in XRF Studies: In X-ray fluorescence (XRF) experiments, determining the most informative sampling spots is crucial. The introduction of BO, informed by GP, has significantly improved the selection process, especially in large or heterogeneous samples. This methodology ensures maximum information gain, optimizing the balance between comprehensive mapping and resource management. Selection of Optimal Energies for XANES Measurements in GEXANES Geometry: In the specific context of X-ray Absorption Near Edge Structure (XANES) studies using Grazing Exit (GEXANES) geometry, the Bayesian approach with Gaussian processes is now utilized to identify the most effective energy settings. This results in detailed spectral data acquired in a much shorter time. We also address challenges and limitations encountered during implementation. Additionally, the versatility of this approach in addressing a range of different research questions will be demonstrated. T2 - Machine Learning Conference for X-Ray and Neutron-Based Experiments CY - Garching bei München, Germany DA - 08.04.2024 KW - BAMline KW - Synchrotron KW - XRF KW - Bayes PY - 2024 AN - OPUS4-61703 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Micro-SR-XRF and Micro-PIXE studies for archaeological gold identification - The case of Carpathian (Transylvanian) gold and of Dacian bracelets T2 - Ecaart 9 CY - Florence, Italy DA - 2007-09-03 PY - 2007 AN - OPUS4-17862 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - SR-XRF analysis of trace amounts of Pt in gold alloys T2 - European Conference on X-ray Spectrometry CY - Dubrovnik, Croatia DA - 2008-06-16 PY - 2008 AN - OPUS4-17845 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - BAMline@BESSY2 - Advanced Techniques and Applications N2 - Synchrotron radiation sources offer a wide range of possibilities in materials research due to their unique properties in terms of intensity, polarization and adjustability. A basic introduction about the creation and special properties of synchrotron radiation will be given. Examples of current work at BAMline, the high-energy measuring facility of the Federal Institute for Materials Research and Testing at the synchrotron BESSY, are used to illustrate the possibilities and limitations of existing measuring methods.” T2 - GDCH Kolloquium CY - Clausthal-Zellerfeld, Germany DA - 17.11.2022 KW - Synchrotron KW - BAMline KW - XRF KW - XANES PY - 2022 AN - OPUS4-61706 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Trace element analysis with synchrotron radiation N2 - Trace elements are chemical elements whose concentration in a material is very low. The exact definition depends on the application and varies for example between 100 micrograms per gram in analytical chemistry and 1000 micrograms per gram in geology. The ability to detect trace elements fast and quantitatively is of great importance in many areas of science and technology. With its high brilliance and flexibility in the excitation conditions, synchrotron radiation is an ideal tool for detecting traces even in small sample quantities. In this contribution I will report about the use of X-ray fluorescence(XRF)for qualitative and quantitative element sensitiveanalysis. In addition to the fundamentals of XRF and its quantification methods, the advantages and problems of different geometries like e.g. microXRF, Total Reflection X-ray Fluorescence (TXRF)or Double Dispersive XRF (D²XRF) will be discussed. Practical examples from BAMline from the research fields of medicine, geology and archaeometry will complete the lecture. T2 - Denver X-Ray Conference CY - Online meeting DA - 03.08.2020 KW - Synchrotron KW - BAMline KW - XRF PY - 2020 AN - OPUS4-51890 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Radtke, Martin A1 - Vincze, L. A1 - Görner, Wolf T1 - Quantification of energy dispersive SRXRF for the certification of reference materials at BAMline N2 - The certification of reference materials (CRMs) is one of the main tasks of the BAM Federal Institute for Materials Research and Testing. In this context CRMs for analytical chemistry play the dominant role. Traditionally, energy dispersive X-ray fluorescence (EDXRF) has been excluded from the final certification scheme. It has lacked the proof to be reliable enough due to peak overlapping and risks of incorrect background subtraction leading to unacceptable uncertainty and bias of the results. The development described aims at enabling ED-SRXRF to really contribute to certification by the aid of synchrotron radiation. This has been partly shown for macrocontents and has been successfully demonstrated for trace elements and thin layers. The method is based on a combination of measurements of pure elements or stoichiometric compounds as comparator materials and Monte Carlo simulations. Measurements have been performed at the BAMline, the hard X-ray beam line of the BAM at the synchrotron BESSY II in Berlin. KW - SyXRF Quantifizierung KW - Monte Carlo Simulation KW - Referenzmaterialien PY - 2010 DO - https://doi.org/10.1039/b926596a SN - 0267-9477 SN - 1364-5544 VL - 25 IS - 5 SP - 631 EP - 634 PB - Royal Society of Chemistry CY - London AN - OPUS4-22895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Guerra, M. F. A1 - Radtke, Martin A1 - Reiche, I. A1 - Riesemeier, Heinrich A1 - Strub, Erik T1 - Analysis of trace elements in gold alloys by SR-XRF at high energy at the BAMline N2 - Measuring in a non-destructive way the characteristic trace elements of the metal allows following the circulation of gold in the past. The aim of this work is to probe the possibilities of X-ray fluorescence with high energy synchrotron radiation (SR-XRF) at the BAMline at BESSY II to determine the concentration of Pt in ancient gold alloys. A HP-Ge detector was used to measure the Pt K-lines excited with an incident energy of 79.5 keV. Data processing was done by subtraction of a Pt free gold standard spectrum from the spectrum of the sample. Depending on the sample composition, the MDL ranges between 40 and 90 ppm. The first results obtained for a small set of gold alloys of different thickness, size and composition showed that high energy SR-XRF is a significant method for the non-destructive determination of Pt in gold. KW - SR-XRF KW - Gold KW - Provenancing KW - Trace elements PY - 2008 DO - https://doi.org/10.1016/j.nimb.2008.03.008 SN - 0168-583X SN - 1872-9584 VL - 266 IS - 10 SP - 2334 EP - 2338 PB - Elsevier CY - Amsterdam AN - OPUS4-17735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Machine learning - Examples from BAM Line N2 - This talk explores applications of artificial intelligence in the field of spectroscopy, with a special focus on research conducted at BAMline. We begin with an overview of synchrotron radiation and its unique capabilities in material analysis. The first part of the talk will cover the integration of AI algorithms in quantifying X-ray fluorescence measurements, providing enhanced precision and efficiency in data analysis. Following this, we will examine the role of language models in spectroscopic research, showcasing how these tools can facilitate the control of complex experimental set-ups T2 - Analytical Academy CY - Berlin, Germany DA - 12.11.2024 KW - ChatGPT KW - Neural networks KW - XRF KW - Synchrotron KW - BAMline PY - 2024 AN - OPUS4-61698 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin 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 T1 - From Egypt to Hiddensee – Analysis of Gold with Synchrotron Radiation IV N2 - Gold is one of the seven metals already known in antiquity and was used from time immemorial as a medium of exchange and for the production of jewelry because of its luster and rarity. In addition, it is easy to work and largely resistant to chemical influences. Investigations of gold using synchrotron radiation excited X-ray fluorescence analysis are non-destructive and provide information about the chemical elements present in the sample under investigation. The investigations presented here at BAMline focus on questions such as the origin, manufacturing process, and association of gold findings. The different questions are explained by a number of examples ranging from the Viking treasure from Hiddensee to the Nebra Sky Disk and finds from Egypt. The find from Bernstorf is discussed in detail. A Bayesian treatment of the authenticity is shown. T2 - Ringvorlesung Einführung in die Archäometrie CY - Berlin, Germany DA - 04.11.2022 KW - Synchrotron KW - BAMline KW - Bayesian Statistics KW - Gold KW - Röntgenfluoreszenz PY - 2022 AN - OPUS4-56252 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 - CONF A1 - Radtke, Martin T1 - Detection of platinum in gold with D2XRF T2 - SR2A 2014 CY - Paris (Frankreich) DA - 2014-09-09 PY - 2014 AN - OPUS4-32369 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 - 2011-11-23 PY - 2011 AN - OPUS4-26926 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Von Ägypten bis Hiddensee – Analyse von Gold mit Synchrotronstrahlung N2 - Gold ist eines der sieben schon im Altertum bekannten Metalle und wurde wg. seines Glanzes und seiner Seltenheit von alters her als Tauschmittel und zur Herstellung von Schmuck benutzt. Außerdem ist es einfach bearbeitbar und weitestgehend gegen chemische Einflüsse resistent. Die Untersuchungen von Gold mit synchrotronstrahlungsangeregter Röntgenfluoreszenzanalyse sind zerstörungsfrei und geben Auskunft über die in der untersuchten Probe vorhandenen chemischen Elemente. Bei den hier vorgestellten Untersuchungen an der BAMline stehen Fragestellungen wie Herkunft, Herstellungsverfahren und Zusammengehörigkeit von Goldfunden im Vordergrund. Die verschiedenen Fragestellungen werden an einer Reihe von Beispielen erläutert die vom Wikingerschatz aus Hiddensee über die Himmelsscheibe von Nebra bis hin zu Funden aus Ägypten langen. Zusätzlich werden die modernen Messmethoden vorgestellt, die am Synchrotron heutzutage zur Verfügung stehen. T2 - Vorlesung FU Berlin Einführung in die Archäometrie CY - Berlin, Germany DA - 04.11.2016 KW - Synchrotron KW - BAMline KW - Gold KW - XRF PY - 2016 AN - OPUS4-38810 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - The Colour X-ray Camera – Basics and Applications of a 2D X-ray Detector N2 - The Color X-ray Camera CXC or SLcam® is an energy-resolving X-ray camera capable of energy- and space-resolved measurements. It consists of a high-speed CCD detector coupled to a polycapil-lary optic that conducts the X-ray photons from the probe to distinct pixels onto the detector. The camera is capable of fast acquisition of spatially and energy resolved fluorescence images. A dedicated software enables the acquisition and the online processing of the spectral data for all 69696 pixels, leading to a real-time visualization of the elements distribution in a sample. It was developed in a joint project with BAM, IFG Berlin and PN Sensors. In this contribution we will mainly discuss the use of the CXC at our beamline, the BAMline at BESSY II and imaging applications of the CXC from different areas, like biology and archaeometry. Additionally new developments for the use of the detector without optics, like wavelength dispersive detection or 1shot-XANES, will be presented. T2 - Seminar Strahlenphysikalische Anwendungen in Technik und Medizin CY - Wien, Austria DA - 20.01.2016 KW - Synchrotron KW - BAMline KW - XRF PY - 2016 AN - OPUS4-38811 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Es ist nicht alles Gold was glänzt - Die Analyse von Gold mit Synchrotronstrahlung N2 - Gold ist eines der sieben schon im Altertum bekannten Metalle und wurde wg. seines Glanzes und seiner Seltenheit von alters her als Tauschmittel und zur Herstellung von Schmuck benutzt. Außerdem ist es einfach bearbeitbar und weitestgehend gegen chemische Einflüsse resistent. Die Untersuchungen von Gold mit synchrotronstrahlungsangeregter Röntgenfluoreszenzanalyse sind zerstörungsfrei und geben Auskunft über die in der untersuchten Probe vorhandenen chemischen Elemente. Bei den hier vorgestellten Untersuchungen an der BAMline stehen Fragestellungen wie Herkunft, Herstellungsverfahren und Zusammengehörigkeit von Goldfunden im Vordergrund. Die verschiedenen Fragestellungen werden an einer Reihe von Beispielen erläutert die vom Wikingerschatz aus Hiddensee über die Himmelsscheibe von Nebra bis hin zu Funden aus Ägypten langen. Zusätzlich werden die modernen Messmethoden vorgestellt, die am Synchrotron heutzutage zur Verfügung stehen. T2 - Vortragsreihe „Naturwissenschaftliche Einsichten in Kunst- und Kulturgut" CY - Dresden, Germany DA - 13.10.2016 KW - Synchrotron KW - BAMline KW - Gold KW - XRF PY - 2016 AN - OPUS4-38809 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - First in situ measurements with a newly developed SR-based ‘Single-shot‘ EXAFS set-up N2 - The newly developed EXAFS set-up comprises both time- and spatially-resolved EXAFS information simultaneously in a single-shot. This facile, stable and scanningless set-up was tested at the BAMline @ BESSY-II (Berlin, Germany). The primary broadband beam is generated by a filter/X-ray-mirror combination (bandpass). The transmitted beam through the sample is diffracted by a convexly bent Si (111) crystal, producing a divergent beam. This, in turn, is collected by an area sensitive detector based on a CCD camera, in a theta - 2 theta geometry. The first in situ measurements were successfully carried out and hereby presented. The case-study involved a well known reaction, in which structural changes are induced over time, and continuously measured. We were able to track structural changes within a 1s time resolution. T2 - European Conference on X-Ray Spectrometry (EXRS) CY - Gothenburg, Sweden DA - 19.06.2016 KW - Synchrotron KW - BAMline KW - EXAFS PY - 2016 AN - OPUS4-38807 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nikolic, Nela A1 - Dal Co, Alma A1 - Kiviet, Daniel J. A1 - Bergmiller, Tobias A1 - Littmann, Sten A1 - Kuypers, Marcel M. M. A1 - Ackermann, Martin A1 - Schreiber, Frank T1 - Cell-to-cell variation and specialization in sugar metabolism in clonal bacterial populations N2 - While we have good understanding of bacterial metabolism at the population level, we know little about the metabolic behavior of individual cells: do single cells in clonal populations sometimes specialize on different metabolic pathways? Such metabolic specialization could be driven by stochastic gene expression and could provide individual cells with growth benefits of specialization. We measured the degree of phenotypic specialization in two parallel metabolic pathways, the assimilation of glucose and arabinose. We grew Escherichia coli in chemostats, and used isotope-labeled sugars in combination with nanometer-scale secondary ion mass spectrometry and mathematical modeling to quantify sugar assimilation at the single-cell level. We found large variation in metabolic activities between single cells, both in absolute assimilation and in the degree to which individual cells specialize in the assimilation of different sugars. Analysis of transcriptional reporters indicated that this variation was at least partially based on cell-to-cell variation in gene expression. Metabolic differences between cells in clonal populations could potentially reduce metabolic incompatibilities between different pathways, and increase the rate at which parallel reactions can be performed. KW - Metabolism KW - Escherichia coli KW - Phenotypic diversity KW - Phenotypic heterogeneity PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-438873 UR - http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1007122 DO - https://doi.org/10.1371/journal.pgen.1007122 SN - 1553-7404 VL - 13 IS - 12 SP - e1007122, 1 EP - e1007122, 24 PB - Public Library of Science CY - Cambridge, United Kingdom AN - OPUS4-43887 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 - Tschirschwitz, Rico A1 - Krentel, Daniel A1 - Kluge, Martin A1 - Askar, Enis A1 - Habib, Abdel Karim A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. A1 - Storm, Sven-Uwe A1 - Rudolph, Michael A1 - Schoppa, André A1 - Sczepaniak, Mariusz T1 - Mobile gas cylinders in fire: Consequences in case of failure N2 - Commercial, off-the shelf propane cylinders are subjected to high safety regulations. Furthermore, those cylinders are equipped with safety devices like pressure relief valves (PRV). Despite these regulations and safety measures, a failure of the container is possible if exposed to an intense fire. The result of this is severe hazard for users, rescue forces and infrastructure. Within the framework of a destructive test series, 15 identical propane cylinders, without pressure relief devices, were exposed to an intensive fire in horizontal position until failure. Each cylinder was filled with a mass of m =11 kg of liquid propane. Three different fire sources were used (wood, petrol, propane). The experiments revealed the failure of all cylinders in a time period t < 155 s. The failure lead to a fragmentation into several major parts with throwing distances of up to l =262 m. In all trials, the temperature of the cylinder wall (top, side, bottom), of the liquid phase inside and of the surrounding fire (top, side, bottom) was recorded. In addition, the inner cylinder pressure and the induced overpressure of the blast wave after the failure were recorded. Overpressures of up to p=0.27 bar were recorded close to the cylinder (l =5 m). All tests were documented by video from several positions (general view, close-up, high-speed 5000 fps). This test series creates the basis for further experimental studies in the field of alternative fuels for vehicles. The aim of this test series is to assess and analyse the consequences of the failure of gas vessels (for LPG, CNG, CGH2) in the aftermath of severe incidents. KW - Explosion KW - Gas cylinders KW - Consequences PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S037971121730098X DO - https://doi.org/10.1016/j.firesaf.2017.05.006 SN - 0379-7112 SN - 1873-7226 VL - 91 SP - 989 EP - 996 PB - Elsevier AN - OPUS4-40550 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Werrel, Martin T1 - Oxygen-reduced Cone Calorimeter - Characteristic effects on the calculation of the heat release rate T2 - ISO-Meeting CY - Brussels, Belgium DA - 2011-11-02 PY - 2011 AN - OPUS4-24710 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - SRXRF - measurements at non planar objects: Automatic determination of the angle of inicidence of the exciting X-ray T2 - Synchroton Radiation in Art & Avhaelogy (SR2A-2010) CY - Amsterdam, Netherlands DA - 2010-11-07 PY - 2010 AN - OPUS4-21378 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rodrigues, M. A1 - Schreiner, M. A1 - Mäder, M. A1 - Melcher, M. A1 - Guerra, M. A1 - Salomon, J. A1 - Radtke, Martin A1 - Alram, M. A1 - Schindel, N. T1 - The hoard of Becin - non-destructive analysis of the silver coins N2 - We report the results of an analytical investigation on 416 silver-copper coins stemming from the Ottoman Empire (end of 16th and beginning of 17th centuries), using synchrotron micro X-ray fluorescence analysis (SRXRF). In the past, analyses had already been conducted with energy dispersive X-ray fluorescence analysis (EDXRF), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM/EDX) and proton induced X-ray emission spectroscopy (PIXE).With this combination of techniques it was possible to confirm the fineness of the coinage as well as to study the provenance of the alloy used for the coins. For the interpretation of the data statistical analysis (principal component analysis—PCA) has been performed. A definite local assignment was explored and significant clustering was obtained regarding the minor and trace elements composing the coin alloys. KW - SRXRF KW - Silber KW - Archaeometrie PY - 2010 DO - https://doi.org/10.1007/s00339-010-5627-y SN - 0947-8396 VL - 99 IS - 2 SP - 351 EP - 356 PB - Springer CY - Berlin AN - OPUS4-23170 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Constantinescu, B. A1 - Oberländer-Târnoveanu, E. A1 - Bugoi, R. A1 - Cojocaru, V. A1 - Radtke, Martin T1 - The Sarmizegetusa bracelets N2 - We present the authentication and analysis of these beautiful Dacian bracelets of the first century BC, originally pillaged by treasure hunters and recovered thanks to an international crime chase. They were originally fashioned from gold panned from the rivers or dug from the mines of Transylvania and hammered into the form of coiled snakes. The lack of context is the greatest loss, but a votive purpose is likely given their proximity to the great sacred centre at Sarmizegetusa Regia. KW - Romania KW - Sarmizegetusa KW - Dacian KW - First century BC KW - Gold KW - Bracelets KW - Hoard KW - Sacred centre KW - World heritage site PY - 2010 UR - http://antiquity.ac.uk/ant/084/ant0841028.htm SN - 0003-598x VL - 84 SP - 1028 EP - 1042 PB - Univ. Press CY - Oxford AN - OPUS4-23169 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - First images of a colour X-ray camera, a detector with high resolution in energy and space T2 - Technart 2011 CY - Berlin, Germany DA - 2011-04-26 PY - 2011 AN - OPUS4-23082 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Röntgenfluoreszenzanalyse mit Synchrotronstrahlung an derr Bundesanstalt für Materialforschung und -prüfung (BAM), Berlin T2 - Seminar: Strahlenphysikalische Anwendungen in Technik und Medizin CY - Vienna, Austria DA - 2010-01-13 PY - 2010 AN - OPUS4-23261 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 - Synchrotronstrahlung für die Untersuchung von Kunstobjekten T2 - DGZfP Arbeitskreis Dresden CY - Dresden, Germany DA - 2010-12-09 PY - 2010 AN - OPUS4-23264 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - XRF using synchrotron radiation T2 - Vienna summer school 2010 "Radiation physics in cultural heritage studies" CY - Vienna, Austria DA - 2010-09-21 PY - 2010 AN - OPUS4-23263 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Materialforschung an der BAMline T2 - Seminar Strahlenphysikalische Anwendungen in Technik und Medizin CY - Vienna, Austria DA - 2010-01-13 PY - 2010 AN - OPUS4-23605 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin 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 T1 - X-ray Fluorescence analysis using synchrotron radiation excitation T2 - 75. Jahrestagung der DPG und DPG Frühjahrstagung CY - Dresden, Germany DA - 2011-03-13 PY - 2011 AN - OPUS4-24023 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 - JOUR A1 - Gauert, C. A1 - Schannor, M. A1 - Hecht, L. A1 - Radtke, Martin A1 - Reinholz, Uwe T1 - A comparison of in situ analytical methods for trace element measurement in gold samples from various South African gold deposits N2 - Trace element concentrations in gold grains from various geological units in South Africa were measured in situ by field emission-electron probe microanalysis (FE-EPMA), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and synchrotron micro X-ray fluorescence spectroscopy (SR-µ-XRF). This study assesses the accuracy, precision and detection limits of these mostly non-destructive analytical methods using certified reference materials and discusses their application in natural sample measurement. FE-EPMA point analyses yielded reproducible and discernible concentrations for Au and trace concentrations of S, Cu, Ti, Hg, Fe and Ni, with detection limits well below the actual concentrations in the gold. LA-ICP-MS analyses required larger gold particles (> 60 µm) to avoid contamination during measurement. Elements that measured above detection limits included Ag, Cu, Ti, Fe, Pt, Pd, Mn, Cr, Ni, Sn, Hg, Pb, As and Te, which can be used for geochemical characterisation and gold fingerprinting. Although LA-ICP-MS measurements had lower detection limits, precision was lower than FE-EPMA and SR-µ-XRF. The higher variability in absolute values measured by LA-ICP-MS, possibly due to micro-inclusions, had to be critically assessed. Non-destructive point analyses of gold alloys by SR-µ-XRF revealed Ag, Fe, Cu, Ni, Pb, Ti, Sb, U, Cr, Co, As, Y and Zr in the various gold samples. Detection limits were mostly lower than those for elements measured by FE-EPMA, but higher than those for elements measured by LA-ICP-MS. N2 - Les concentrations en éléments traces de grains d'or provenant de différentes unités géologiques d'Afrique du Sud ont été mesurées in situ par microsonde électronique à émission de champ (FE-EPMA), spectrométrie de masse couplée à une source plasma et un système d'ablation laser (LA-ICP-MS) et micro spectroscopie de fluorescence des rayons X au Synchrotron (SR-µ-XRF). Cette étude évalue l'exactitude, la précision et les limites de détection de ces méthodes d'analyse pour la plupart non-destructives en utilisant des matériaux de référence certifiés, et discute de leur application dans les mesures sur échantillon naturel. Les points d'analyses FE-EPMA ont fournis des concentrations reproductibles et discernables pour l'Au et des concentrations en traces de S, Cu, Ti, Hg, Fe et Ni, avec des limites de détection bien inférieures aux concentrations réelles dans l'or. Les analyses LA-ICP-MS ont nécessitées des particules d'or de plus grande taille (> 60 µm) pour éviter toute contamination pendant la mesure. Les éléments mesurés au-dessus des limites de détection inclus Ag, Cu, Ti, Fe, Pt, Pd, Mn, Cr, Ni, Sn, Hg, Pb, A et Te, qui peuvent être utilisés pour les caractérisations géochimique et le «fingerprinting» de l'or. Bien que les mesures LA-ICP-MS aient des limites de détection plus basses, la précision est inférieure par rapport à celles de la microsonde FE et de la SR-µ-XRF. La plus grande variabilité des valeurs absolues mesurées par LA-ICP-MS, probablement reliée à la présence de micro-inclusions, a du être évaluée de manière critique. Les points d'analyse non-destructifs des alliages d'or par SR-µ-XRF ont révélés la présence de Ag, Fe, Cu, Ni, Pb, Ti, Sb, U, Cr, Co, As, Y et Zr dans les différents échantillons. Les limites de détection ont été pour la plupart inférieures à celles des éléments mesurés par FE-EPMA, mais supérieures à celles des éléments mesurés par LA-ICP-MS. KW - Trace elements KW - Gold KW - FE-EPMA KW - LA-ICP-MS KW - SR-µ-XRF KW - Precision KW - Précision KW - Comparison of techniques KW - Éléments traces PY - 2016 DO - https://doi.org/10.1111/j.1751-908X.2015.00362.x SN - 1639-4488 SN - 1751-908X VL - 40 IS - 2 SP - 267 EP - 289 PB - Blackwell CY - Oxford AN - OPUS4-34882 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - First experiences with the combination of polycapillary optics and an energy dispersive pn- CCD detector at BAMline at Bessy T2 - X-ray micro-fluorescence spectroscopy at the PETRA III extension: second user workshop CY - Hamburg, Germany DA - 2011-09-27 PY - 2011 AN - OPUS4-26924 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Materialforschung an der BAMline T2 - Seminar Strahlenphysikalische Anwendungen in Technik und Medizin CY - Vienna, Austria DA - 2009-01-28 PY - 2009 AN - OPUS4-19183 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin A1 - Stalinski, T. T1 - Adaptive Kanalreduktion eines hyperspektralen Bilddatensatzes kombiniert mit k-mean Clustering T2 - Workshop Farbbildverarbeitung - Wuppertal 2014 CY - Wuppertal DA - 2014-09-25 PY - 2014 AN - OPUS4-32365 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Das goldene Zeitalter war damals Analyse von Gold mit Synchrotronstrahlung N2 - Gold ist eines der sieben bereits in der Antike bekannten Metalle und wurde wegen seines Glanzes und seiner Seltenheit seit jeher als Tauschmittel und zur Herstellung von Schmuck verwendet. Außerdem ist es leicht zu bearbeiten und weitgehend resistent gegen chemische Einflüsse. Die Analyse von Gold mit der durch Synchrotronstrahlung angeregten Röntgenfluoreszenzanalyse ist zerstörungsfrei und liefert Informationen über die in der untersuchten Probe vorhandenen chemischen Elemente. Im Mittelpunkt der hier vorgestellten Untersuchungen an der BAMline stehen Fragen nach der Herkunft, dem Herstellungsprozess und der Zugehörigkeit von Goldfunden. Die verschiedenen Fragestellungen werden anhand einer Reihe von Beispielen erläutert, die vom Wikingerschatz von Hiddensee über die Himmelsscheibe von Nebra bis hin zu Funden aus Ägypten reichen. Darüber hinaus werden die heute am Synchrotron verfügbaren modernen Messmethoden vorgestellt. T2 - WISSENSCHAFT MIT WIRKUNG: Workshop Kulturguterhaltung – vom Dampfkessel zu Nanomaterialien CY - Berlin, Germany DA - 17.11.2021 KW - Gold KW - Synchrotron KW - Bernstorf KW - Nebra KW - XRF PY - 2021 AN - OPUS4-54139 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rodrigues, M. A1 - Cappa, F. A1 - Schreiner, M. A1 - Ferloni, P. A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Woytek, B. A1 - Alram, M. T1 - Further metallurgical analyses on silver coins of Trajan (AD 98-117) N2 - Within an interdisciplinary project, preliminary results of which were published in 2007, a group of 65 silver coins (denarii) of Trajan, evenly distributed over the entire span of his reign (2nd to 6th consulate), as well as 3 coins from the reign of his predecessor, the emperor Nerva (AD 96–98), had been acquired on the coin market. These pieces could be cross-sectioned in order to carry out analyses. Measurements were performed with µ-XRF and µ-SRXRF to check the fineness of the denarius alloy as well as to investigate if the coins of the different consulates showed distinct traits concerning the main impurities which could suggest a change of ore sources. Furthermore, it was examined whether the influx of precious metals into the Roman treasury after Trajan's Dacian campaigns (AD 101/102 and 105/106) could have had any repercussions on the composition of the denarius alloy; comparative data was provided by the analysis of nine imitations of Roman Republican denarii presumably struck in Dacia. Documentation of the cross-sections was performed with SEM/EDX in order to clarify details concerning the specific microstructure of the coins. An enrichment of Ag of approx. 100 to 200 µm in the near surface regions of most of the coins could be observed, which is due to corrosion effects. Previous metallographic analyses done by several scholars had been inadequate to clarify the central numismatic and economic questions. With the presented analyses, it was possible to correct the results of the earlier research and to provide, for the first time, a secure basis of data for the investigation of the development of the silver alloy used for denarii in Trajan's reign. PY - 2011 DO - https://doi.org/10.1039/c0ja00252f SN - 0267-9477 SN - 1364-5544 VL - 26 IS - 5 SP - 873 EP - 1100 PB - Royal Society of Chemistry CY - London AN - OPUS4-23623 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - Machine learning for direct quantification of XRF measurements N2 - In this talk I’ll describe the use of artificial neural networks (ANN) for quantifying X-ray fluorescence (XRF) measurements. The main idea of this talk is to give an overview of the process needed to generate a model that can then be applied to a specific problem. In XRF, a sample is excited with X-rays and the resulting characteristic radiation is detected to determine elements quantitatively and qualitatively. This is traditionally done in several time-consuming steps. I’ll show the possibilities and problems of using a neural network to realise a "one-click" quantification. This includes generating training data using Monte Carlo simulation and augmenting the existing data set with an ANN to generate more data. The search for the optimal hyperparameters, manually and automatically, is also described. For the case presented, we were able to train a network with a mean absolute error of 0.1% by weight for the synthetic data and 0.7% by weight for a set of experimental data obtained with certified reference materials. T2 - Seminar series: Artificial Intelligence applied to X-ray / synchrotron techniques CY - Online meeting DA - 24.06.2021 KW - Artificial intelligence KW - Machine learning KW - Synchrotron KW - XRF PY - 2021 AN - OPUS4-54140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Radtke, Martin T1 - 3D and Beyond - Basics and Applications of the Color X-ray Camera T2 - Denver X-ray Conference CY - BIG SKY RESORT, BIG SKY, MONTana, USA DA - 2014-07-28 PY - 2014 AN - OPUS4-32366 LA - deu 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 -