TY - JOUR A1 - Hildebrandt, Jana A1 - Taubert, Andreas A1 - Thünemann, Andreas T1 - Synthesis and Characterization of Ultra‐Small Gold Nanoparticles in the Ionic Liquid 1‐Ethyl‐3‐methylimidazolium Dicyanamide, [Emim][DCA] N2 - AbstractWe report on gold clusters with around 62 gold atoms and a diameter of 1.15±0.10 nm. Dispersions of the clusters are long‐term stable for two years at ambient conditions. The synthesis was performed by mixing tetrachloroauric acid (HAuCl4 ⋅ 3 H2O) with the ionic liquid 1‐ethyl‐3‐methylimidazolium dicyanamide ([Emim][DCA]) at temperatures of 20 to 80 °C. Characterization was performed with small‐angle X‐ray scattering (SAXS), UV‐Vis spectroscopy, and MALDI‐TOF mass spectrometry. A three‐stage model is proposed for the formation of the clusters, in which cluster growth from gold nuclei takes place according to the Lifshitz‐Slyozov‐Wagner (LSW) model followed by oriented attachment to form colloidal stable clusters. KW - Reference materials KW - SAXS KW - Gold KW - Nanoparticle KW - Small-angle X-ray scattering KW - Ionic liquid PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-588203 DO - https://doi.org/10.1002/open.202300106 SN - 2191-1363 VL - 44 SP - 1 EP - 19 PB - Wiley AN - OPUS4-58820 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hildebrandt, Jana A1 - Thünemann, Andreas T1 - Aqueous Dispersions of Polypropylene: Toward Reference Materials for Characterizing Nanoplastics N2 - Microplastics and nanoplastics pollute the natural environment all over the world, but the full extent of the hazards posed by this waste is unclear. While research on microplastics is well advanced, little work has been done on nanoplastics. This discrepancy is mainly due to the lacking ability to detect nanoplastics in biologically and environmentally relevant matrices. Nanoplastics reference materials can help the development of suitable methods for identifying and quantifying nanoplastics in nature. The aim is to synthesize nanoplastics made from one of the most commonly used plastics, namely polypropylene. An easy way to produce long-term stable aqueous dispersions of polypropylene nanoparticles (nano polypropylene) is reported. The nanoplastic particles, prepared by mechanical breakdown, show a mean hydrodynamic diameter of D h = 180.5 ± 5.8 nm and a polydispersity index of PDI = 0.084 ± 0.02. No surfactant is needed to obtain dispersion which is stable for more than 6 months. The colloidal stability of the surfactant-free nano polypropylene dispersions is explained by their low zeta potential of 𝜻 = −43 ± 2 mV. KW - Nanoparticles KW - Reference Material KW - Nanoplastics PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571799 DO - https://doi.org/10.1002/marc.202200874 SN - 1022-1336 VL - 44 IS - 6 SP - 1 EP - 15 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57179 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kinne, Marko A1 - Farhan, Muhammad A1 - Schneider, Ronald A1 - Thöns, Sebastian T1 - Influence of the structural integrity management on the levelized cost of energy of offshore wind: a parametric sensitivity analysis N2 - The levelized cost of energy (LCoE) is an important measure to quantify the macro-economic efficiency of an offshore wind farm and to enable a quantitative comparison with other types of energy production. The costs of the structural integrity management - which is required to ensure an adequate lifetime reliability of the turbine support structures - are part of the operational expenditures of an offshore wind farm. An optimization of the structural integrity management may reduce the operational expenditures and consequently the LCoE. However, the effect of the structural integrity management on the LCoE is hardly known. To investigate this effect, this paper presents a sensitivity analysis of the LCoE of a generic offshore wind farm. The probabilistic models of the parameters influencing the LCoE are based on a literature study including an explicit model for the structural integrity management. The analysis reveals that LCoE may potentially be reduced if an optimization of the structural integrity management enables a service life extension. T2 - International Probabilistic Workshop 2022 CY - Stellenbosch, South Africa DA - 08.09.2022 KW - Structural integrity management KW - Levelized cost of energy KW - Sensitivity analysis PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-572724 DO - https://doi.org/10.14311/APP.2022.36.0090 VL - 36 SP - 90 EP - 98 PB - Acta Polytechnica CTU Proceedings AN - OPUS4-57272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sauermoser-Yri, M. A1 - Veldurthi, N. A1 - Wölfle, C. H. A1 - Svartvatn, P. J. A1 - Flo Hoem, S. O. A1 - Lid, M. J. A1 - Bock, Robert A1 - Palko, J. A1 - Torgersen, J. T1 - On the porosity-dependent permeability and conductivity of triply periodic minimal surface based porous media N2 - With the fast development in the field of additive manufacturing, triply periodic minimal surface (TPMS) based porous media have recently found many uses in mechanical property tuning. However, there is still a lack of understanding in their porosity-dependent permeability and electrical as well as thermal conductivity. Here, we perform finite volume simulations on the solid and void domains of the Schoen gyroid (SG), Schwarz primitive (SP) and Schwarz primitive beam (SPB) TPMS with porosities between 63% and 88% in Ansys Fluent. A simple cubic lattice (CL) of equivalent porosity served as reference. The SPB and CL showed up to one order of magnitude higher permeabilities than the SG and SP. However, SG and SP have about 1.3 and 2.6 times the electrical and thermal conductivity of SPB and CL, respectively. Furthermore, the properties of SPB and CL are largely affected by the surface area density, whereas tortuosity variation does not impact permeability and conductivity to a major extent. Finally, empirical relations are adapted to describe the presented data and thus, they may enable future designers of TPMS based porous structures to fine-tune the geometries according to the requirements on permeability and electrical as well as thermal conductivity. KW - Metals and Alloys KW - Surfaces, Coatings and Films KW - Biomaterials KW - Ceramics and Composites PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-585250 DO - https://doi.org/10.1016/j.jmrt.2023.09.242 SN - 2238-7854 VL - 27 SP - 585 EP - 599 PB - Elsevier B.V. AN - OPUS4-58525 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hajhariri, Aliasghar A1 - Eberwein, Robert A1 - Perrone, Luca Pakj A1 - Cozzani, Valerio A1 - Otremba, Frank A1 - Seidlitz, Holger T1 - Study the impact of spacer at thermal degradation process of MLI-based insulation in fire condition N2 - To reduce CO2 emissions, energy carriers such as hydrogen are considered to be a solution. Consumption of hydrogen as a fuel meets several limitations such as its low volumetric energy density in gas phase. To tackle this problem, storage as well as transportation in liquified phase is recommended. To be able to handle this component in liquid phase, an efficient thermal insulation e.g., MLI insulation is required. Different studies have been addressed the vulnerability of such insulation against high thermal loads e.g., in an accident engaging fire. Some of research works have highlighted the importance of considering the MLI thermal degradation focusing on its reflective layer. However, limited number of studies addressed the thermal degradation of spacer material and its effect on the overall heat flux. In this study, through systematic experimental measurements, the effect of thermal loads on glass fleece, glass paper as well as polyester spacers are investigated. The results are reported in various temperature and heat flux profiles. Interpreting the temperature profiles revealed that, as the number of spacers in the medium increases, the peak temperature detectable by the temperature sensor on the measurement plate decreases. Each individual spacer contributes to mitigating the radiative energy received by the measurement plate. Stacks of 20–50 spacers (this is the number of layers in commercial MLI systems applied for liquid hydrogen applications) can potentially reduce the thermal radiation by 1–2 orders of magnitude. An empirical correlation to predict a heat flux attenuation factor is proposed, which is useful for further numerical and analytical studies in the temperature range from ambient to 300 ◦C. KW - Cryogenic KW - Liquid Hydrogen KW - Multi-Layer Insultation KW - Heat Transfer KW - Hydrogen Storage Safety PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-614919 DO - https://doi.org/10.1016/j.jlp.2024.105461 SN - 0950-4230 VL - 92 SP - 1 EP - 7 PB - Elsevier Ltd. AN - OPUS4-61491 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Camplese, Davide A1 - Scarponi, Giordano Emrys A1 - Chianese, Carmela A1 - Hajhariri, Aliasghar A1 - Eberwein, Robert A1 - Otremba, Frank A1 - Cozzani, Valerio T1 - Modeling the performance of multilayer insulation in cryogenic tanks undergoing external fire scenarios N2 - Multilayer Insulation (MLI) is frequently used in vacuum conditions for the thermal insulation of cryogenic storage tanks. The severe consequences of the degradation of such materials in engulfing fire scenarios were recently evidenced by several large-scale experimental tests. In the present study, an innovative modelling approach was developed to assess the performance of heat transfer in polyester-based MLI materials for cryogenic applications under fire conditions. A specific layer-by-layer approach was integrated with an apparent kinetic thermal degradation model based on thermogravimetric analysis results. The modeling results provided a realistic simulation of the experimental data obtained by High-Temperature Thermal Vacuum Chamber tests reproducing fire exposure conditions. The model was then applied to assess the behavior of MLI systems for liquid hydrogen tanks in realistic fire scenarios. The results show that in intense fire scenarios degradation occurs rapidly, compromising the thermal insulation performances of the system within a few minutes. KW - Multilayer Insulation KW - Cryogenic Vessels KW - Liquefied Hydrogen KW - Liquefied Natural Gas KW - Safety KW - Fire PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-599418 DO - https://doi.org/10.1016/j.psep.2024.04.061 SN - 0957-5820 VL - 186 SP - 1169 EP - 1182 PB - Elsevier B.V. AN - OPUS4-59941 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Theiler, Geraldine A1 - Gradt, Thomas T1 - Comparison of the sliding behavior of several polymers in gaseous and liquid hydrogen N2 - The development of hydrogen technologies entails high safety requirements in distribution and dispensing infrastructure. Therefore, it is necessary to pursue research on material compatibility in hydrogen, especially for critical parts with tribological issues. The focus of this study is to evaluate the influence of hydrogen on a wider range of commercially available polymer materials. Thereby, the friction and wear behavior of different grades of TPE, POM, PA66, PA12, PPA, PEEK, PPS, PTFE, PAI, PI and PBI were investigated against a rotating steel disk (AISI 304). Filled and unfilled polymers from different suppliers were evaluated at room temperature in air, vacuum and hydrogen gas (H2) as well as in liquid hydrogen at - 253°C (LH2). The sliding behavior of the polymer materials is discussed by means of surface analyses, whereby special attention is paid to the formation of a transfer film. According to the results at ambient temperature, the effect of hydrogen environment on the tribological behavior of neat polymers may be related to lack of moisture, but also to saturated hydrocarbons in gaseous hydrogen. In liquid hydrogen, the best tribological performances were achieved with neat PA polymers as well as PPS and PI composites. KW - Polymers KW - Composites KW - Sliding wear KW - Hydrogen KW - Cryogenic temperature PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597123 DO - https://doi.org/10.2474/trol.18.217 SN - 1881-2198 VL - 18 IS - 5 SP - 217 EP - 231 PB - Japanese Society of Tribologists AN - OPUS4-59712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Theiler, Geraldine A1 - Gradt, Thomas T1 - Influence of counterface and environment on the tribological behaviour of polymer materials N2 - This paper focuses on the influence of the counterface materials on the sliding behaviour of polymer materials in hydrogen. Polyimide (PI), polyetheretherketone (PEEK) and Polytetrafluoroethylene (PTFE) materials were investigated against hardened 52100 martensitic bearing steel and 304 austenitic stainless steel with similar roughness (Ra = 0.2 μm). Results indicate that the friction and wear of PI and PEEK materials depend on the counterface material. This effect wasn’t observed for PTFE composites. While the tribological performance of polyimide is better against 52100 in hydrogen, improved sliding behaviour of PEEK materials is observed with 304 counterface, particularly at higher sliding speed. Surface analyses of the transfer film reveal that the influence of the counterface is primarily related to the chemical nature of the steel for PI and to the thermal conductivity of the disc for PEEK materials. KW - Friction KW - Wear KW - Polymers KW - Hydrogen Transfer Film PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-515483 DO - https://doi.org/10.1016/j.polymertesting.2020.106912 VL - 93 SP - 106912 PB - Elsevier Ltd. AN - OPUS4-51548 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Giannakopoulos, Antonios E. A1 - Zisis, Athanasios A1 - Zervaki, Anna D. A1 - Dimopoulos, Christos D. A1 - Platypodis, Efstathios A1 - Eberwein, Robert T1 - Effective elastic moduli and failure mechanisms of a random assembly of thin walled glass microbubbles N2 - In this work a methodology is presented to estimate the elastic properties and failure mechanisms of an assembly of random, brittle microbubbles. The approach is based on the mechanics of frictionless micro-contact between hollow spherical shells by employing relations from classical shell theory and verified by two dimensional axisymmetric Finite Elements. The estimated values are in agreement with available experimental values. Moreover, a granular type analytical homogenization model provides an isotropic elastic constitutive law to be used for the macroscopic deformation of an assembly of glass micro-bubbles when it is compressed by external loads. In addition, approximate estimates are also proposed for two important micro-failure mechanisms of such assemblies that relate either to the splitting or to the buckling of a brittle spherical shell, prior its complete crushing. The results are novel and are expected to enhance the application of glass microbubbles directly in acute thermal insulation problems such as liquid hydrogen storage. KW - LH2 KW - Cryogenic Vessels KW - Insulation PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-634354 DO - https://doi.org/10.1016/j.ijsolstr.2025.113528 SN - 0020-7683 VL - 320 SP - 1 EP - 11 PB - Elsevier BV CY - Amsterdam AN - OPUS4-63435 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lumpe, H. A1 - Menke, A. A1 - Haisch, C. A1 - Mayer, P. A1 - Kabelitz, Anke A1 - Yusenko, Kirill A1 - de Oliveira Guilherme Buzanich, Ana A1 - Block, T. A1 - Pöttgen, R. A1 - Emmerling, Franziska A1 - Daumann, L. J. T1 - The Earlier the Better: Structural Analysis and Separation of Lanthanides with Pyrroloquinoline Quinone N2 - Lanthanides (Ln) are critical raw materials, however, their mining and purification have a considerable negative environmental impact and sustainable recycling and separation strategies for these elements are needed. In this study, the precipitation and solubility behavior of Ln complexes with pyrroloquinoline quinone (PQQ), the cofactor of recently discovered lanthanide (Ln) dependent methanol Dehydrogenase (MDH) enzymes, is presented. In this context, the molecular structure of a biorelevant europium PQQ complex was for the first time elucidated outside a protein environment. The complex crystallizes as an inversion symmetric dimer, Eu2PQQ2, with binding of Eu in the biologically relevant pocket of PQQ. LnPQQ and Ln1Ln2PQQ complexes were characterized by using inductively coupled Plasma mass spectrometry (ICP-MS), infrared (IR) spectroscopy, 151Eu-Mössbauer spectroscopy, X-ray total scattering, and Extended X-ray absorption fine structure (EXAFS). It is shown that a natural enzymatic cofactor is capable to achieve Separation by precipitation of the notoriously similar, and thus difficult to separate, lanthanides to some extent. KW - Lanthanides KW - Structural Analysis KW - Separation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510821 DO - https://doi.org/10.1002/chem.202002653 SN - 0947-6539 VL - 26 SP - 1 EP - 8 PB - WILEY-VCH Verlag GmbH & co. KGaA AN - OPUS4-51082 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Emmerling, Franziska ED - Rogge, Andreas ED - Meng, Birgit T1 - Exploring new materials for Green Intelligent Building - How can our BAMline help? N2 - In the scope of exploring and characterizing new materials related to Green Intelligent Building (GIB), we will provide an overview of the X-ray spectroscopy and diffraction analytical methods available at the BAMline /1/. and Myspot beamlines. These are two universal beamlines at the Berlin Synchrotron BESSY-II, where BAM has access and supervision role. Overarching electronic and structural properties at different time and length scales, such measurements enable a real-time characterization of materials properties. We will show-case in situ and ex situ deterioration and hydration studies on cement-based constructure materials. T2 - 11. Jahrestagung des DAfStb mit 63. Forschungskolloquium der BAM Green Intelligent Building CY - Berlin, Germany DA - 16.10.2024 KW - BAMline KW - Scope of exploring KW - Green intelligent building PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-612882 SN - 978-3-9818564-7-7 SP - 30 EP - 36 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-61288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wilke, Manuel A1 - Kabelitz, Anke A1 - Gorelik, T. E. A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe A1 - Kolb, U. A1 - Rademann, K. A1 - Emmerling, Franziska T1 - The crystallisation of copper(II) phenylphosphonates N2 - The crystal structures and syntheses of four different copper(II) phenylphosphonates, the monophenylphosphonates α-, β-, and γ-Cu(O3PC6H5)·H2O (α-CuPhPmH (1) β-CuPhPmH (2) and γ-CuPhPmH (3)), and the diphosphonate Cu(HO3PC6H5)2·H2O (CuPhP2mH (4)), are presented. The compounds were synthesized from solution at room temperature, at elevated temperature, under hydrothermal conditions, and mechanochemical conditions. The structures of α-CuPhPmH (1) and CuPhP2mH (4) were solved from powder X-ray diffraction data. The structure of β-CuPhPmH (2) was solved by single crystal X-ray analysis. The structures were validated by extended X-ray absorption fine structure (EXAFS) and DTA analyses. Disorder of the crystal structure was elucidated by electron diffraction. The relationship between the compounds and their reaction pathways were investigated by in situ synchrotron measurements. KW - Mechanochemistry KW - Metal phosphonate KW - In situ PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-384217 DO - https://doi.org/10.1039/C6DT02904C SN - 1477-9226 SN - 1477-9234 VL - 45 IS - 43 SP - 17453 EP - 17463 PB - The Royal Society of Chemistry AN - OPUS4-38421 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 - JOUR A1 - Kabelitz, Anke A1 - de Oliveira Guilherme Buzanich, Ana A1 - Joester, Maike A1 - Reinholz, Uwe A1 - Radtke, Martin A1 - Bienert, Ralf A1 - Schulz, K. A1 - Schmack, R. A1 - Kraehnert, R. A1 - Emmerling, Franziska T1 - Time-resolved in situ studies on the formation mechanism of iron oxide nanoparticles using combined fast-XANES and SAXS N2 - The reaction of iron chlorides with an alkaline reagent is one of the most prominent methods for the synthesis of iron oxide nanoparticles. We studied the particle formation mechanism using triethanolamine as reactant and stabilizing agent. In situ fast-X-ray absorption near edge spectroscopy and small-angle X-ray scattering provide information on the oxidation state and the structural information at the same time. In situ data were complemented by ex situ transmission electron microscopy, wide-angle X-ray scattering and Raman analysis of the formed nanoparticles. The formation of maghemite nanoparticles (γ-Fe2O3) from ferric and ferrous chloride was investigated. Prior to the formation of these nanoparticles, the formation and conversion of intermediate phases (akaganeite, iron(II, III) hydroxides) was observed which undergoes a morphological and structural collapse. The thus formed small magnetite nanoparticles (Fe3O4) grow further and convert to maghemite with increasing reaction time. KW - oxidation state KW - structural information KW - maghemite PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351376 DO - https://doi.org/10.1039/C5CE01585E SN - 1466-8033 VL - 17 IS - 44 SP - 8463 EP - 8470 CY - London, UK AN - OPUS4-35137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wilke, Manuel A1 - de Oliveira Guilherme Buzanich, Ana A1 - Reinholz, Uwe A1 - Rademann, Klaus A1 - Emmerling, Franziska T1 - The structure and in situ synthesis investigation of isomorphic mononuclear molecular metal phenylphosphonates N2 - We describe a fast and effective synthesis for molecular metal phosphonates. Isomorphic compounds [M(II)(HO₃PPh)₂(H₂O₃PPh)₂(H₂O)₂] (M = Mn (1), Co (2), Ni (3); Ph = C₆H₅) were obtained by grinding. The complexes are mononuclear compounds containing neutral and monodeprotonated phenylphosphonic acid and water as ligands. The crystal structures were determined using powder X-ray diffraction (PXRD) data and validated by extended X-ray absorption fine structure (EXAFS) data. Combined synchrotron XRD measurements and Raman spectroscopy were conducted for investigating the reactions in situ. Based on these data, the intermediates were characterized and the formation mechanism was derived. KW - Mechanochemistry KW - Metal phosphonate KW - In situ KW - XRD PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-363944 DO - https://doi.org/10.1039/c6dt00787b SN - 1477-9226 SN - 1477-9234 SN - 1364-5447 VL - 45 IS - 23 SP - 9460 EP - 9467 AN - OPUS4-36394 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nowak, S.H. A1 - Bjeoumikhov, A. A1 - Von Borany, J. A1 - Buchriegler, J. A1 - Munnik, F. A1 - Petric, M. A1 - Radtke, Martin A1 - Renno, A.D. A1 - Reinholz, Uwe A1 - Scharf, O. A1 - Wedell, R. T1 - Sub-pixel resolution with a color X-ray camera N2 - The color X-ray camera SLcam® is a full-field, single photon detector providing scanning-free, energy and spatially resolved X-ray imaging. Spatial resolution is achieved with the use of polycapillary optics guiding X-ray photons from small regions on a sample to distinct energy dispersive pixels on a charged-coupled device detector. Applying sub-pixel resolution, signals from individual capillary channels can be distinguished. Therefore, the SLcam® spatial resolution, which is normally limited to the pixel size of the charge-coupled device, can be improved to the size of individual polycapillary channels. In this work a new approach to a sub-pixel resolution algorithm comprising photon events also from the pixel centers is proposed. The details of the employed numerical method and several sub-pixel resolution examples are presented and discussed. KW - Color X-ray camera KW - Sub pixel analysis PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-334948 DO - https://doi.org/10.1039/c5ja00028a SN - 0267-9477 SN - 1364-5544 SP - 1890 EP - 1897 PB - Royal Society of Chemistry CY - London AN - OPUS4-33494 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Oliveira Guilherme Buzanich, Ana A1 - Radtke, Martin A1 - Reinholz, Uwe A1 - Riesemeier, Heinrich A1 - Emmerling, Franziska T1 - Time- & spatial-resolved X-ray absorption fine structure (XAFS) spectroscopy in a single-shot – new analytical possibilities for in situ material characterization N2 - A new concept that comprises both time- and lateral-resolved X-ray absorption fine-structure information simultaneously in a single shot is presented. This uncomplicated set-up was tested at the BAMline at BESSY-II (Berlin, Germany). The primary broadband beam was generated by a double multilayer monochromator. 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 either an energy-sensitive area detector, the so-called color X-ray camera, or by an area-sensitive detector based on a CCD camera, in θ-2θ geometry. The first tests were performed with thin metal foils and some iron oxide mixtures. A time resolution of lower than 1 s together with a spatial resolution in one dimension of at least 50 µm is achieved. KW - Time resolution KW - Single-shot XAFS PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-370892 DO - https://doi.org/10.1107/S1600577516003969 SN - 1600-5775 IS - 23 SP - 769 EP - 776 PB - International Union of Crystallography CY - Chester, UK AN - OPUS4-37089 LA - eng 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 - Mundra, S. A1 - Bernal, S. A. A1 - Criado, M. A1 - Hlaváček, Petr A1 - Ebell, Gino A1 - Reinemann, Steffi A1 - Gluth, Gregor A1 - Provis, J. L. T1 - Steel corrosion in reinforced alkali‐activated materials N2 - The development of alkali‐activated materials (AAMs) as an alternative to Portland cement (PC) has seen significant progress in the past decades. However, there still remains significant uncertainty regarding their long term performance when used in steel‐reinforced structures. The durability of AAMs in such applications depends strongly on the corrosion behaviour of the embedded steel reinforcement, and the experimental data in the literature are limited and in some cases inconsistent. This letter elucidates the role of the chemistry of AAMs on the mechanisms governing passivation and chloride‐induced corrosion of the steel reinforcement, to bring a better understanding of the durability of AAM structures exposed to chloride. The corrosion of the steel reinforcement in AAMs differs significantly from observations in PC; the onset of pitting (or the chloride ‘threshold’ value) depends strongly on the alkalinity, and the redox environment, of these binders. Classifications or standards used to assess the severity of steel corrosion in PC appear not to be directly applicable to AAMs due to important differences in pore solution chemistry and phase assemblage. KW - Corrosion KW - Alkali-activated PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-435162 DO - https://doi.org/10.21809/rilemtechlett.2017.39 SN - 2518-0231 VL - 2 SP - 33 EP - 39 PB - RILEM Publications SARL CY - Paris, France AN - OPUS4-43516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Guerra, M. F. A1 - Fischer, M. A1 - Radtke, Martin A1 - Reinholz, Uwe T1 - Inca figurines from the Ethnologisches Museum in Berlin: an analytical study of some typical and atypical productions N2 - Fourteen hollow and one cast anthropomorphic and zoomorphic figurines produced in Incan times for ritual offerings from the Ethnologisches Museum in Berlin were selected to investigate the technologies and alloys used for their fabrication with portable optical microscopy and non-destructive XRF elemental analysis. This group of gold and silver figurines includes typical specimens of the Inca production, such as the four silver figurines from the Island Coati in Lake Titicaca and the two gold figurines from Pachacamac, as well as specimens that are seldom present in collections, which makes them atypical. In addition to the tall figurines with atypical hair or standing pose, one bicolour figurine half silver, half gold) and another with coloured inlays were included in this study for comparison. The large majority of the silver specimens are made from very high quality alloys and the gold figurines are made from alloys containing low copper contents and silver ranging from 30wt% to 52wt%. KW - Gold KW - pXRF KW - Inca PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-436015 DO - https://doi.org/10.4000/bifea.8232 SN - 0303-7495 VL - 46 IS - 1 SP - 221 EP - 251 PB - Institut Français d'Études Andines AN - OPUS4-43601 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -