TY - JOUR A1 - Brzeska, J. A1 - Elert, Anna Maria A1 - Morawska, M. A1 - Sikorska, W. A1 - Kowalczuk, M. A1 - Rutkowska, M. T1 - Branched Polyurethanes Based on Synthetic Polyhydroxybutyrate with Tunable Structure and Properties N2 - Branched, aliphatic polyurethanes (PURs) were synthesized and compared to linear analogues. The influence of polycaprolactonetriol and synthetic poly([R,S]-3-hydroxybutyrate) (R,S-PHB) in soft segments on structure, thermal and sorptive properties of PURs was determined. Using FTIR and Raman spectroscopies it was found that increasing the R,S-PHB amount in the structure of branched PURs reduced a tendency of urethane groups to hydrogen bonding. Melting enthalpies (on DSC thermograms) of both soft and hard segments of linear PURs were higher than branched PURs, suggesting that linear PURs were more crystalline. Oil sorption by samples of linear and branched PURs, containing only polycaprolactone chains in soft segments, was higher than in the case of samples with R,S-PHB in their structure. Branched PUR without R,S-PHB absorbed the highest amount of oil. Introducing R,S-PHB into the PUR structure increased water sorption. Thus, by operating the number of branching and the amount of poly([R,S]-3-hydroxybutyrate) in soft segments thermal and sorptive properties of aliphatic PURs could be controlled. KW - IR KW - Polyurethane KW - PUR KW - RAMAN PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457087 DO - https://doi.org/10.3390/polym10080826 VL - 10 IS - 8 SP - 826, 1 EP - 12 PB - MDPI AN - OPUS4-45708 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chandra, K. A1 - Kranzmann, Axel T1 - High temperature oxidation of 9–12% Cr ferritic/martensitic steels under dual-environment conditions N2 - In normal operations, the opposite surfaces of the power plant components are exposed to two different environments, i.e. air/flue gas on the one side and steam on the other side. Exposure under such dual-environment can lead to accelerated corrosion of the components on the air side. The oxidation behaviour of ferritic/martensitic steel T92 was investigated under dual-environment in a specially designed test equipment. The samples were exposed to dry oxyfuel flue gas (CO2–27%N2–2%O2–1%SO2) on one side and to steam on the other side up to 1000 h at 650°C. The formation of oxide scales was characterised by optical microscopy and scanning electron microscopy with attached energy-dispersive spectroscopy. Oxidation rate of specimens under dual-Environment condition was almost three times higher than that in single-environment condition. This is explained based on hydrogen transport through the bulk alloy from the steam side to the flue gas side. KW - Oxidation KW - Dual-environment KW - Oxyfuel KW - Ferritic/martensitic steel KW - Steam PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457101 DO - https://doi.org/10.1080/1478422X.2017.1374049 VL - 53 IS - 31 SP - 27 EP - 33 PB - Taylor & Francis AN - OPUS4-45710 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heyn, A. A1 - Müller, Thoralf A1 - Balzer, M. A1 - Fenker, M. A1 - Kappl, H. T1 - Corrosion protection mechanisms of TiMgN hard coatings on steel N2 - Hard coated steel components are used in a wide application range, mostly for protective, wear resistant and decorative purposes. Despite of these coatings being regarded as relatively dense, there is always a high risk of localized corrosion when a coated low alloyed steel component encounters a surrounding high humidity atmosphere or even an aqueous medium. An approach to enhance the corrosion properties is the addition of magnesium to physical vapor deposited hard coatings, like TiN. It has been found that there is a remarkable increase in corrosion resistance in dependence of magnesium content of the TiMgN coating and its surface properties. In this work the authors will explain the underlying corrosion protection mechanisms by means of electrochemical and analytical studies. The positive impact of magnesium in the coating relates on its preferred dissolution vs. steel. This causes the potential to shift to more negative direction with respect to the steel substrate and additionally leads to a temporarily passivation of the steel due to alkalization of the surrounding electrolyte by formation of magnesium hydroxide. T2 - 20. Werkstofftechnisches Kolloquium CY - Chemnitz, Germany DA - 14.03.2018 KW - Corrosion KW - Titanium nitride KW - PVD hard coating KW - magnesium PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457117 DO - https://doi.org/10.1088/1757-899X/373/1/012009 SN - 1757-8981 VL - 373 IS - 1 SP - 012009, 1 EP - 10 PB - IOP Publishing Ltd AN - OPUS4-45711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schreier, Andy A1 - Wosniok, Aleksander A1 - Liehr, Sascha A1 - Krebber, Katerina T1 - Humidity-induced Brillouin frequency shift in perfluorinated polymer optical fibers N2 - We report, to our knowledge, for the first time on humidity-induced Brillouin frequency shifts in perfluorinated graded index polymer optical fibers. A linear relation between Brillouin frequency shift and humidity was observed. Furthermore, the humidity coefficient of the Brillouin frequency shift is demonstrated to be a function of temperature (-107 to -64 kHz/%r.h. or -426 to -49 kHz m3/g in the range of 20 to 60 °C). An analytical description proves temperature and humidity as two mutually independent effects on the Brillouin frequency shift. KW - Brillouin KW - Polymer optical fibre KW - Humidity PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-457165 DO - https://doi.org/10.1364/OE.26.022307 SN - 1094-4087 VL - 26 IS - 17 SP - 22307 EP - 22314 PB - Optical Society of America AN - OPUS4-45716 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 - JOUR A1 - Mech, A. A1 - Wohlleben, W. A1 - Ghanem, A. A1 - Hodoroaba, Vasile-Dan A1 - Weigel, S. A1 - Babick, F. A1 - Brüngel, R. A1 - Friedrich, C. M. A1 - Rasmussen, K. A1 - Rauscher, H. T1 - Nano or Not Nano? A Structured Approach for Identifying Nanomaterials According to the European Commission’s Definition N2 - Identifying nanomaterials (NMs) according to European Union Legislation is challenging, as there is an enormous variety of materials, with different physico-chemical properties. The NanoDefiner Framework and its Decision Support Flow Scheme (DSFS) allow choosing the optimal method to measure the particle size distribution by matching the material properties and the performance of the particular measurement techniques. The DSFS leads to a reliable and economic decision whether a material is an NM or not based on scientific criteria and respecting regulatory requirements. The DSFS starts beyond regulatory requirements by identifying non-NMs by a proxy Approach based on their volume-specific surface area. In a second step, it identifies NMs. The DSFS is tested on real-world materials and is implemented in an e-tool. The DSFS is compared with a decision flowchart of the European Commission’s (EC) Joint Research Centre (JRC), which rigorously follows the explicit criteria of the EC NM definition with the focus on identifying NMs, and non-NMs are identified by exclusion. The two approaches build on the same scientific basis and measurement methods, but start from opposite ends: the JRC Flowchart starts by identifying NMs, whereas the NanoDefiner Framework first identifies non-NMs. KW - Classification KW - Definition KW - Identification KW - Nanomaterials KW - Particle size KW - Regulation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510917 DO - https://doi.org/10.1002/smll.202002228 SN - 1613-6829 SP - 2002228-1 EP - 2002228-16 PB - Wiley-VCH CY - Weinheim AN - OPUS4-51091 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Anja A1 - Possling, A. A1 - Malysheva, N. A1 - Yousef, K. P. A1 - Herbst, S. A1 - von Kleist, M. A1 - Hengge, R. T1 - Local c-di-GMP signaling in the control of synthesis of the E. coli biofilm exopolysaccharide pEtN-cellulose N2 - In many bacteria, the biofilm-promoting second messenger c-di-GMP is produced and degraded by multiple diguanylate cyclases (DGC) and phosphodiesterases (PDE), respectively. High target specificity of some of these enzymes has led to theoretical concepts of "local" c-di-GMP signaling. In Escherichia coli K-12, which has 12 DGCs and 13 PDEs, a single DGC, DgcC, is specifically required for the biosynthesis of the biofilm exopolysaccharide pEtN-cellulose without affecting the cellular c-di-GMP pool, but the mechanistic basis of this target specificity has remained obscure. DGC activity of membrane-associated DgcC, which is demonstrated in vitro in nanodiscs, is shown to be necessary and sufficient to specifically activate cellulose biosynthesis in vivo. DgcC and a particular PDE, PdeK (encoded right next to the cellulose operon), directly interact with cellulose synthase subunit BcsB and with each other, thus establishing physical proximity between cellulose synthase and a local source and sink of c-di-GMP. This arrangement provides a localized, yet open source of c-di-GMP right next to cellulose synthase subunit BcsA, which needs allosteric activation by c-di-GMP. Through mathematical modeling and simulation, we demonstrate that BcsA binding from the low cytosolic c-di-GMP pool in E. coli is negligible, whereas a single c-di-GMP molecule that is produced and released in direct proximity to cellulose synthase increases the probability of c-di-GMP binding to BcsA several hundred-fold. This local c-di-GMP signaling could provide a blueprint for target-specific second messenger signaling also in other bacteria where multiple second messenger producing and degrading enzymes exist. KW - Biofilm KW - Cellulose synthase KW - Bacterial second messenger KW - C-di-GMP PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511214 DO - https://doi.org/10.1016/j.jmb.2020.06.006 SN - 0022-2836 VL - 432 IS - 16 SP - 4576 EP - 4595 PB - Elsevir Ltd. AN - OPUS4-51121 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Artzt, K. A1 - Mishurova, Tatiana A1 - Bauer, P.-P. A1 - Gussone, J. A1 - Barriobero-Vila, P. A1 - Evsevleev, Sergei A1 - Bruno, Giovanni A1 - Requena, G. A1 - Haubrich, J. T1 - Pandora’s Box–Influence of Contour Parameters on Roughness and Subsurface Residual Stresses in Laser Powder Bed Fusion of Ti-6Al-4V N2 - The contour scan strategies in laser powder bed fusion (LPBF) of Ti-6Al-4V were studied at the coupon level. These scan strategies determined the surface qualities and subsurface residual stresses. The correlations to these properties were identified for an optimization of the LPBF processing. The surface roughness and the residual stresses in build direction were linked: combining high laser power and high scan velocities with at least two contour lines substantially reduced the surface roughness, expressed by the arithmetic mean height, from values as high as 30 μm to 13 μm, while the residual stresses rose from ~340 to about 800 MPa. At this stress level, manufactured rocket fuel injector components evidenced macroscopic cracking. A scan strategy completing the contour region at 100 W and 1050 mm/s is recommended as a compromise between residual stresses (625 MPa) and surface quality (14.2 μm). The LPBF builds were monitored with an in-line twin-photodiode-based melt pool monitoring (MPM) system, which revealed a correlation between the intensity quotient I2/I1, the surface roughness, and the residual stresses. Thus, this MPM system can provide a predictive estimate of the surface quality of the samples and resulting residual stresses in the material generated during LPBF. KW - Additive manufacturing KW - Ti-6Al-4V KW - Contour scan strategy KW - Surface roughness KW - Melt pool monitoring KW - Residual stress KW - Synchrotron X-ray diffraction PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510585 DO - https://doi.org/10.3390/ma13153348 VL - 13 IS - 15 SP - 3348 AN - OPUS4-51058 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero-Navarrete, José A. A1 - Otremba, Frank T1 - A method to assess the gravity response efficiency of a truck N2 - In spite that transport activities do not represent the biggest contributor of pollutants emissions, their reduction has been a priority as some other externalities are associated to such emissions and to the transport itself. A crucial element to characterize the behavior of the vehicles against the environment are the losses that such vehicles exhibit in a passive way, that is, without any involvement of power conditions. The energy loses due to the rolling, the drag and to the friction in mechanical components, have been assessed so far in terms of the stopping acceleration when the vehicle idles on a ramp. However, such a testing procedure produces some uncertainties due to the dynamic conditions that are considered. To avoid such critical limitations, in this paper a testing procedure and facility are proposed, which are based on static conditions of the vehicle at the initiation and at the ending of the test, which are assumed to provide a better reliability to the testing. Some preliminary theoretical analysis should be made in order to validate the operational principles proposed herein for such testing facility. KW - Road tankers KW - Energy efficiency KW - Environmental assessment KW - Gravity response KW - Transportation energy KW - Rolling resistance KW - Drag resistance PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511530 UR - https://www.iaras.org/iaras/home/caijes/a-method-to-assess-the-gravity-response-efficiency-of-a-truck SN - 2367-8941 VL - 5 SP - 213 EP - 219 PB - IARAS CY - Sofia AN - OPUS4-51153 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Romero-Navarrete, José A. A1 - Otremba, Frank A1 - Lozano Guzman, A. A. T1 - Estimation of the effect of the driving style on pollutants emission by heavy trucks N2 - Different approaches have been attempted so far to reduce fuel consumption and linked pollutants, including vehicle equipment and design, with rational driving style being recognized as a potential source of fuel savings. However, no specific methodology had been suggested so far to assess fuel economy of driving other than the fuel consumed itself. In this paper, the Standard deviation of driving acceleration has been found to be directly associated to fuel consumption, so that the less dispersion of the driving acceleration, produces the lower fuel consumptions and emissions. Such metric could be thus used to assess driving style. KW - Driving style KW - Fuel consumption KW - Stored energy KW - GPS data KW - Simulation KW - Particle emissions PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511540 UR - https://www.iaras.org/iaras/home/caijes/estimation-of-the-effect-of-the-driving-style-on-pollutants-emission-by-heavy-trucks SN - 2367-8941 VL - 5 SP - 220 EP - 226 PB - IARAS CY - Sofia AN - OPUS4-51154 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hildebrandt, L. A1 - von der Au, Marcus A1 - Zimmermann, T. A1 - Reese, A. A1 - Ludwig, J. A1 - Pröfrock, D. T1 - A metrologically traceable protocol for the quantification of trace metals in different types of microplastic N2 - The presence of microplastic (MP) particles in aquatic environments raised concern About possible enrichment of organic and inorganic pollutants due to their specific surface and chemical properties. In particular the role of metals within this context is still poorly understood. Therefore, the aim of this work was to develop a fully validated acid digestion protocol for metal analysis in different polymers, which is a prerequisite to study such interactions. The proposed digestion protocol was validated using six different certified reference materials in the microplastic size range consisting of polyethylene, polypropylene, acrylonitrile butadiene styrene and polyvinyl chloride. As ICP-MS/MS enabled time-efficient, sensitive and robust analysis of 56 metals in one measurement, the method was suitable to provide mass fractions for a multitude of other elements beside the certified ones (As, Cd, Cr, Hg, Pb, Sb, Sn and Zn). Three different microwaves, different acid mixtures as well as different temperatures in combination with different hold times were tested for optimization purposes. With the exception of Cr in acrylonitrile butadiene styrene, recovery rates obtained using the optimized protocol for all six certified reference materials fell within a range from 95.9% ± 2.7% to 112% ± 7%. Subsequent optimization further enhanced both precision and recoveries ranging from 103% ± 5% to 107 ± 4% (U; k = 2 (n = 3)) for all certified metals (incl. Cr) in acrylonitrile butadiene styrene. The results clearly show the analytical challenges that come along with metal analysis in chemically resistant plastics. Addressing specific analysis Tools for different sorption scenarios and processes as well as the underlying kinetics was beyond this study’s scope. However, the future application of the two recommended thoroughly validated total acid digestion protocols as a first step in the direction of harmonization of metal analysis in/on MP will enhance the significance and comparability of the generated data. It will contribute to a better understanding of the role of MP as vector for trace metals in the environment. KW - Microplatic KW - Digestion KW - Analytical Chemistry PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510727 DO - https://doi.org/10.1371/journal.pone.0236120 VL - 15 IS - 7 SP - e0236120 AN - OPUS4-51072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Khrapov, D. A1 - Surmeneva, M. A1 - Koptioug, A. A1 - Evsevleev, Sergei A1 - Léonard, Fabien A1 - Bruno, Giovanni A1 - Surmenev, R. T1 - X-ray computed tomography of multiple-layered scaffolds with controlled gradient cell lattice structures fabricated via additive manufacturing N2 - In this paper we report on the characterization by X-ray computed tomography of calcium phosphate (CaP) and polycaprolactone (PCL) coatings on Ti-6Al-4V alloy scaffolds used as a material for medical implants. The cylindrical scaffold has greater porosity of the inner part than the external part, thus, mimicking trabecular and cortical bone, respectively. The prismatic scaffolds have uniform porosity. Surface of the scaffolds was modified with calcium phosphate (CaP) and polycaprolactone (PCL) by dip-coating to improve biocompatibility and mechanical properties. Computed tomography performed with X-ray and synchrotron radiation revealed the defects of structure and morphology of CaP and PCL coatings showing small platelet-like and spider-web-like structures, respectively.  KW - Mechanical Engineering KW - Maskinteknik PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510763 DO - https://doi.org/10.1088/1742-6596/1145/1/012044 SN - 17426588 VL - 1145 SP - 012044 PB - IOP AN - OPUS4-51076 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholtz, G. A1 - Staude, Andreas A1 - Dunlop, J.A. T1 - Trilobite compound eyes with crystalline cones and rhabdoms show mandibulate affinities N2 - Most knowledge about the structure, function, and evolution of early compound eyes is based on investigations in trilobites. However, these studies dealt mainly with the cuticular lenses and little was known about internal anatomy. Only recently some data on crystalline cones and retinula cells were reported for a Cambrian trilobite species. Here, we describe internal eye structures of two other trilobite genera. The Ordovician Asaphus sp. reveals preserved crystalline cones situated underneath the cuticular lenses. The same is true for the Devonian species Archegonus (Waribole) warsteinensis, which in addition shows the fine structure of the rhabdom in the retinula cells. These results suggest that an apposition eye with a crystalline cone is ancestral for Trilobita. The overall similarity of trilobite eyes to those of myriapods, crustaceans, and hexapods corroborates views of a phylogenetic position of trilobites in the stem lineage of Mandibulata. KW - Trilobite compound eyes KW - Computed Tomography PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510784 DO - https://doi.org/10.1038/s41467-019-10459-8 SN - 2041-1723 VL - 10 SP - 2503 PB - Nature AN - OPUS4-51078 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Biegler, M. A1 - Wang, J. A1 - Kaiser, L. A1 - Rethmeier, Michael T1 - Automated Tool-Path Generation for Rapid Manufacturing of Additive Manufacturing Directed Energy Deposition Geometries N2 - In additive manufacturing (AM) directed energy deposition (DED), parts are built by welding layers of powder or wire feedstock onto a substrate with applications for steel powders in the fields of forging tools, spare parts, and structural components for various industries. For large and bulky parts, the choice of toolpaths influences the build rate, the mechanical performance, and the distortions in a highly geometry-dependent manner. With weld-path lengths in the range of hundreds of meters, a reliable, automated tool-path generation is essential for the usability of DED processes. This contribution presents automated tool-path generation approaches and discusses the results for arbitrary geometries. Socalled “zig-zag” and “contour-parallel” processing strategies are investigated and the tool-paths are automatically formatted into machine-readable g-code for experimental validation to build sample geometries. The results are discussed in regard to volume-fill, microstructure, and porosity in dependence of the path planning according to photographs and metallographic cross-sections. KW - Porosity KW - Path planning KW - Mechanical properties KW - Laser metal deposition KW - Additive manufacturing PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510454 DO - https://doi.org/10.1002/srin.202000017 VL - 91 IS - 11 SP - 2000017 PB - WILEY-VCH Verlag GmbH & co. KGaA CY - Weinheim AN - OPUS4-51045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zimmermann, T. A1 - von der Au, Marcus A1 - Reese, A. A1 - Klein, O. A1 - Hildebrandt, L. A1 - Pröfrock, D. T1 - Substituting HF by HBF4 – an optimized digestion method for multi-elemental sediment analysis via ICP-MS/MS N2 - Determination of elemental mass fractions in sediments plays a major role in evaluating the environmental status of aquatic ecosystems. Herewith, the optimization of a new total digestion protocol and the subsequent analysis of 48 elements in different sediment reference materials (NIST SRM 2702, GBW 07313, GBW 07311 and JMC-2) based on ICP-MS/MS detection is presented. The developed method applies microwave acid digestion and utilizes HBF4 as fluoride source for silicate decomposition. Similar to established protocols based on HF, HBF4 ensures the dissolution of the silicate matrix, as well as other refractory oxides. As HBF4 is not acutely toxic; no special precautions have to be made and digests can be directly measured via ICP-MS without specific sample inlet systems, evaporation steps or the addition of e.g. H3BO3, in order to mask excess HF. Different acid mixtures with and without HBF4 were evaluated in terms of digestion efficiency based on the trace metal recovery. The optimized protocol (5 mL HNO3, 2 mL HCL, 1 mL HBF4) allows a complete dissolution of the analyzed reference materials, as well as quantitative recoveries for a wide variety of certified analytes. Low recoveries for e.g. Sr, Ba and rare earth elements due to fluoride precipitation of HF-based digestions protocols, can be avoided by the usage of HBF4 instead. Based on the usage of high purity HBF4 all relevant trace, as well as matrix elements can be analyzed with sufficiently low LOQs (0.002 μg L−1 for U up to 6.7 μg L−1 for Al). In total, 34 elements were within a recovery range of 80%–120% for all three analyzed reference materials GBW 07313, GBW 07311 and JMC-2. 14 elements were outside a recovery range of 80%–120% for at least one of the analyzed reference materials. KW - Reference Materials KW - Sediment KW - HF free Digestion PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510480 DO - https://doi.org/10.1039/D0AY01049A SP - 1 EP - 10 PB - Royal Society of Chemistry AN - OPUS4-51048 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yusenko, Kirill A1 - Khandarkhaeva, S. A1 - Bykov, M. A1 - Fedotenko, T. A1 - Hanfland, M. A1 - Sukhikh, A. A1 - Gromilov, S. A1 - Dubrovinsky, L. T1 - Face-centered cubic refractory alloys prepared from single-source precursors N2 - Three binary fcc-structured alloys (fcc–Ir0.50Pt0.50, fcc Rh0.66Pt0.33 and fcc–Rh0.50Pd0.50) were 14 prepared from [Ir(NH3)5Cl][PtCl6], [Ir(NH3)5Cl][PtBr6], [Rh(NH3)5Cl]2[PtCl6]Cl2 and 15 [Rh(NH3)5Cl][PdCl4]·H2O, respectively, as single-source precursors. All alloys were prepared by 16 thermal decomposition in gaseous hydrogen flow below 800 °C. Fcc–Ir0.50Pt0.50 and fcc–Rh0.50Pd0.50 17 correspond to miscibility gaps on binary metallic phase diagrams and can be considered as 18 metastable alloys. Detailed comparison of [Ir(NH3)5Cl][PtCl6] and [Ir(NH3)5Cl][PtBr6] crystal 19 structures suggests that two isoformular salts are not isostructural. In [Ir(NH3)5Cl][PtBr6], specific 20 Br…Br interactions are responsible for crystal structure arrangement. Room temperature 21 compressibility of fcc–Ir0.50Pt0.50, fcc–Rh0.66Pt0.33 and fcc–Rh0.50Pd0.50 has been investigated up to 50 GPa 22 in diamond anvil cells. All investigated fcc-structured binary alloys are stable under compression. 23 Atomic volumes and bulk moduli show good agreement with ideal solutions model. For fcc–24 Ir0.50Pt0.50, V0/Z = 14.597(6) Å3·atom-1, B0 = 321(6) GPa, B0' = 6(1); for fcc–Rh0.66Pt0.33, V0/Z = 14.211(3) 25 Å3·atom-1, B0 =259(1) GPa, B0' = 6.66(9); for fcc–Rh0.50Pd0.50, V0/Z = 14.18(2) Å3·atom-1, B0 =223(4) GPa, 26 B0' = 5.0(3). KW - High-pressure KW - Refractory alloys KW - Platinum group metals KW - Single-source precursors PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508176 DO - https://doi.org/10.3390/ma13061418 VL - 13 IS - 6 SP - 1418 PB - MDPI CY - Basel AN - OPUS4-50817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yusenko, Kirill A1 - Domonov, D. A1 - Pechenyuk, S. A1 - Belyevskii, A. T1 - Formation of Nanostructured Carbon from [Ni(NH3)6]3[Fe(CN)6]2 N2 - The products of thermal decomposition in an argon atmosphere of [Ni(NH3)6]3[Fe(CN)6]2 as a precursor has been studied. Decomposition products were studied up to 800◦C. Above 600◦C, all coordination bonds in the residues are broken with a formation of Ni3Fe, Fe, and free carbon with a small admixture of nitrogen. Elementary carbon can be easily separated from metals by treatment with a water solution of hydrochloric acid. Only carbon is responsible for the specific surface of the composite products. The released carbon has a high degree of graphitization and begins to oxidize in air above 500°C and is completely oxidized above 700°C. KW - Carbon materials KW - Double complex compound KW - Thermal decomposition PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508188 DO - https://doi.org/10.3390/nano10020389 VL - 10 IS - 2 SP - 389 PB - MDPI CY - Basel AN - OPUS4-50818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yusenko, Kirill A1 - Sukhikh, A. A1 - Kraus, Werner A1 - Gromilov, S. T1 - Synthesis and Crystal Chemistry of Octahedral Rhodium(III) Chloroamines N2 - Rhodium(III) octahedral complexes with amine and chloride ligands are the most common starting compounds for preparing catalytically active rhodium(I) and rhodium(III) species. Despite intensive study during the last 100 years, synthesis and crystal structures of rhodium(III) complexes were described only briefly. Some [RhClx(NH3)6-x] compounds are still unknown. In this study, available information about synthetic protocols and the crystal structures of possible [RhClx(NH3)6−x] octahedral species are summarized and critically analyzed. Unknown crystal structuresof(NH4)2[Rh(NH3)Cl5],trans–[Rh(NH3)4Cl2]Cl·H2O,andcis–[Rh(NH3)4Cl2]Clarereported based on high quality single crystal X-ray diffraction data. The crystal structure of [Rh(NH3)5Cl]Cl2 was redetermined. All available crystal structures with octahedral complexes [RhClx(NH3)6-x] were analyzed in terms of their packings and pseudo-translational sublattices. Pseudo-translation lattices suggest face-centered cubic and hexagonal closed-packed sub-cells, where Rh atoms occupy nearly ideal lattices. KW - Pseudo-translationalsublattices KW - Rhodiumcomplexes KW - Ligandsubstitution KW - Crystalstructure PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508194 DO - https://doi.org/10.3390/molecules25040768 VL - 25 IS - 4 SP - 768 PB - MDPI CY - Basel AN - OPUS4-50819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishurova, Tatiana A1 - Sydow, B. A1 - Thiede, Tobias A1 - Sizova, I. A1 - Ulbricht, Alexander A1 - Bambach, M. A1 - Bruno, Giovanni T1 - Residual Stress and Microstructure of a Ti-6Al-4V Wire Arc Additive Manufacturing Hybrid Demonstrator N2 - Wire Arc Additive Manufacturing (WAAM) features high deposition rates and, thus, allows production of large components that are relevant for aerospace applications. However, a lot of aerospace parts are currently produced by forging or machining alone to ensure fast production and to obtain good mechanical properties; the use of these conventional process routes causes high tooling and material costs. A hybrid approach (a combination of forging and WAAM) allows making production more efficient. In this fashion, further structural or functional features can be built in any direction without using additional tools for every part. By using a combination of forging basic geometries with one tool set and adding the functional features by means of WAAM, the tool costs and material waste can be reduced compared to either completely forged or machined parts. One of the factors influencing the structural integrity of additively manufactured parts are (high) residual stresses, generated during the build process. In this study, the triaxial residual stress profiles in a hybrid WAAM part are reported, as determined by neutron diffraction. The analysis is complemented by microstructural investigations, showing a gradient of microstructure (shape and size of grains) along the part height. The highest residual stresses were found in the transition Zone (between WAAM and forged part). The total stress range showed to be lower than expected for WAAM components. This could be explained by the thermal history of the component. KW - Additive manufacturing KW - Neutron diffraction KW - Residual stress KW - Hybrid manufacturing KW - WAAM KW - Ti-6Al-4V PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508245 DO - https://doi.org/10.3390/met10060701 VL - 10 IS - 6 SP - 701 PB - MDPI AN - OPUS4-50824 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Taparli, Ugur Alp A1 - Kannengießer, Thomas A1 - Griesche, Axel T1 - Tungsten inert gas bead-on-plate weld chemical composition analysis by laser-induced breakdown spectroscopy N2 - Chemical compositions of a weld can be varying locally as a result of the welding process. These local variations can be due to the vaporization of individual alloying elements. In this work, tungsten inert gas (TIG) bead-on-plate stainless steel welds of EN grade 1.4404 and 1.4435 were investigated using laser-induced breakdown spectroscopy (LIBS) on the completed welds. This study aims to reveal the welding parameters’ influence on the resulting local chemical compositions of the stainless steel welds. We demonstrated Mn vaporize before Cr due to its lower latent enthalpy of vaporization. Hence, Mn accumulates on the heat-affected zone (HAZ) both sides across the weld bead by being swept away through the circulation flow of the welding plasma. Additionally, increasing the heat input tends to enhance the accumulated Mn content on the HAZ as well as increasing the shielding gas flow rate. The results are in good agreement with the literature and proved that LIBS is an effective method to inspect completed welds. T2 - Symposium on Materials and Joining Technology CY - Magdeburg, Germany DA - 07.09.2020 KW - LIBS TIG welding KW - Austenitic stainless steels KW - Chemical composition KW - In situ measurement PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511595 DO - https://doi.org/10.1088/1757-899X/882/1/012023 SN - 1757-8981 SN - 1757-899X VL - 882 IS - 012023 SP - 1 EP - 8 PB - IOP Publishing CY - Bristol AN - OPUS4-51159 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Wetzel, Annica A1 - Oczan, Ozlem A1 - Nietzke, Jonathan A1 - Richter, Tim A1 - Schröpfer, Dirk T1 - Hydrogen diffusion and local Volta potential in high- and medium-entropy alloys N2 - High-entropy alloys (HEAs) are characterized by a solid solution of minimum five and medium-entropy alloys (MEAs) of minimum three principal alloying elements in equiatomic proportions. They show exceptional application properties, such as high-strength and ductility or corrosion resistance. Future HEA/MEA-components could be exposed to hydrogen containing environments like vessels for cryogenic or high-pressure storage where the hydrogen absorption and diffusion in these materials is of interest. In our study, we investigated the HEA Co20Cr20Fe20Mn20Ni20 and the MEA Co33.3Cr33.3Ni33.3. For hydrogen ingress, cathodic charging was applied and diffusion kinetic was measured by high-resolution thermal desorption spectros-copy using different heating rates up to 0.250 K/s. Peak deconvolution resulted in high-temperature desorption peaks and hydrogen trapping above 280 °C. A total hydrogen concentration > 40 ppm was identified for the MEA and > 100 ppm for HEA. This indicates two important effects: (1) delayed hydrogen diffusion and (2) considerable amount of trapped hydrogen that must be anticipated for hydrogen assisted cracking phenomenon. Local electrochemical Volta potential maps had been measured for the hydrogen free condition by means of high-resolution Scanning Kelvin Probe Force Microscopy (SKPFM). T2 - Symposium on Materials and Joining Technology CY - Online meeting DA - 07.09.2020 KW - Hydrogen KW - High-entropy alloy KW - Diffusion KW - Scanning kelvin probe force microscopy KW - Corrosion PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511684 DO - https://doi.org/10.1088/1757-899X/882/1/012015 VL - 882 SP - 1 EP - 15 PB - IOP Publishing CY - Bristol AN - OPUS4-51168 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schaupp, Thomas A1 - Ernst, W. A1 - Spindler, H. A1 - Kannengießer, Thomas T1 - Hydrogen-assisted cracking of GMA welded 960 MPa grade high-strength steels N2 - High-strength steels with yield strength of 960 MPa are susceptible to hydrogen-assisted cracking (HAC) during welding processing. In the present paper, the implant test is used to study HAC in a quenched and tempered steel S960QL and a high-strength steel produced by thermo-mechanical controlled process S960MC. Welding is performed using the gas metal arc welding process. Furthermore, diffusible hydrogen concentration (HD) in arc weld metal is determined. Based on the implant test results, lower critical stress (LCS) for complete fracture, critical implant stress for crack initiation, and embrittlement index (EI) are determined. At HD of 1.66 ml/100 g, LCS is 605 MPa and 817 MPa for S960QL and S960MC, respectively. EI is 0.30 and 0.46 for S960QL and S960MC, respectively. Fracture surfaces of S960QL show higher degradation with reduced deformation. Both, higher EI of S960MC and fractography show better resistance to HAC in the HAZ of S960MC compared to S960QL. KW - High-strength steel KW - Welding KW - Diffusible hydrogen KW - Hydrogen-assisted cracking KW - Heat-affected zone KW - Implant test PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510307 DO - https://doi.org/10.1016/j.ijhydene.2020.05.077 SN - 0360-3199 VL - 45 IS - 38 SP - 20080 EP - 20093 PB - Elsevier Ltd CY - Amsterdam, NL AN - OPUS4-51030 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen T1 - The Ring-Opening Polymerisation-Polycondensation (ROPPOC) Approach to cyclic Polymers N2 - A new concept called “Ring-Opening Polymerization (ROP) combined with simultaneous POlyCondensation” (ROPPOC) is presented and discussed. This synthetic strategy is based on the intermediate formation of chains having two end groups that can react with each other. The ROPPOC syntheses are subdivided into three groups according to the nature of the chain ends: two ionic end groups, one ionic and one covalent chain end and a combination of two reactive covalent end groups may be involved, depending on the catalyst. The usefulness for the preparation of cyclic polymers is discussed with a review of numerous previously published examples. These examples concern to following classes of cyclic polymers: polypeptides, polyamides, polyesters, including polycarbonates, and cyclic polysiloxanes. It is demonstrated, that the results of certain ROPPOC syntheses are in contradiction to the Jacobson-Stockmayer theory. Finally, the usefulness of ROPPOCs for the detection of polydisperse catenanes is discussed. KW - Ring-opening Polymerisation KW - MALDI-TOF MS KW - ROPPOC KW - Cyclic PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508509 DO - https://doi.org/10.1002/marc.202000152 SP - 2000152 PB - Wiley AN - OPUS4-50850 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Moll, J. A1 - Wang, Cui A1 - Päpcke, A. A1 - Förster, C. A1 - Resch-Genger, Ute A1 - Lochbrunner, S. A1 - Heinze, K. T1 - Green Light Activation of Push-Pull Ruthenium(II) Complexes N2 - Synthesis, characterization, electrochemistry, and photophysics of novel homo- and heteroleptic ruthenium(II) complexes [Ru(cpmp)2] 2+ (22+) and [Ru(cpmp)(ddpd)]2+ (32+) bearing the tridentate ligands 6,2’’-carboxypyridyl-2,2’-methylamine-pyridylpyridine (cpmp) and N,N’-dimethyl-N,N’-dipyridin-2-ylpyridine-2,6-diamine (ddpd) are reported. The complexes possess one (32+) or two (22+) electron-deficient dipyridyl ketone fragments as electron accepting sites enabling intraligand charge transfer (ILCT), ligand-toligand charge transfer (LL’CT) and low-energy metal-to-ligand charge transfer (MLCT) absorptions. The latter peak around 544 nm (green light). 22+ shows 3MLCT phosphorescence in the red to near-infrared spectral region at room temperature in deaerated acetonitrile solution with an emission quantum yield of 1.3 % and a 3MLCT lifetime of 477 ns, while 3 2+ is much less luminescent. This different behaviour is ascribed to the energy gap law and the shape of the parasitic excited 3MC state potential energy surface. This study highlights the importance of the excited state energies and geometries for the actual excited state dynamics. Aromatic and aliphatic amines reductively quench the excited state of 22+ paving the way to photocatalytic applications using low-energy green light as exemplified with the green-light sensitized thiol-ene click reaction. KW - Green light excitation KW - Ruthenium(II) complexes KW - Phosphorescence KW - MLCT KW - Photoinduced electron transfer PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506759 DO - https://doi.org/10.1002/chem.202000871 SP - 1 EP - 13 PB - Wiley-VCH Verlag AN - OPUS4-50675 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Babutzka, Martin A1 - Müller, Thoralf A1 - Mietz, Jürgen A1 - Burkert, Andreas T1 - Investigation of the influence of iron‐containing abrasives on the corrosion behaviour of the aluminium alloy AlSi1.2Mg0.4 N2 - The corrosion resistance of aluminium surfaces is closely linked to the surfacecstate after a grinding process. For years, iron‐containing abrasive materials were suspected to lead to increased corrosion susceptibility after processing of aluminium surfaces. To prove a possible correlation between the iron content of an abrasive and the corrosion behaviour of aluminium components, scientific investigations and experimentally practical corrosion tests are necessary. For the current investigation, specimens of a technical Al‐Si alloy from the same batch were used. The test specimens were mechanically ground with various resin‐bonded model abrasives containing different iron contents. The performed corrosion tests did not reveal a negative influence of the different iron‐containing abrasives on the corrosion behaviour of the Al–Si alloy. However, the most sensitive measuring method (electrochemical noise) showed differences in the surface activity depending on the type of abrasive. KW - Aluminium KW - Corrosion KW - Corrosion testing KW - Grinding PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506762 DO - https://doi.org/10.1002/maco.202011657 SN - 0947-5117 SN - 1521-4176 VL - 71 IS - 10 SP - 1667 EP - 1679 PB - Wiley‐VCH Verlag GmbH & Co. KGaA CY - Weinheim AN - OPUS4-50676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Waurischk, Tina A1 - Müller, Ralf A1 - Reinsch, Stefan A1 - Kiefer, P. A1 - Deubener, J. A1 - Balzer, R. A1 - Behrens, H. T1 - Crack Growth in Hydrous Soda-Lime Silicate Glass N2 - Stable crack growth was measured for nominal dry and water-bearing (6 wt%) soda-lime silicate glasses in double cantilever beam geometry and combined with DMA studies on the effects of dissolved water on internal friction and glass transition, respectively. In vacuum, a decreased slope of logarithmic crack growth velocity versus stress intensity factor is evident for the hydrous glass in line with an increase of b-relaxation intensity indicating more energy Dissipation during fracture. Further, inert crack growth in hydrous glass is found to be divided into sections of different slope, which indicates different water related crack propagation mechanism. In ambient air, a largely extended region II is observed for the hydrous glass, which indicates that crack growth is more sensitive to ambient water. KW - Internal friction KW - Soda-lime silicate glass KW - Water content KW - Stable crack growth KW - DCB geometry KW - Stress intensity factor PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506829 DO - https://doi.org/10.3389/fmats.2020.00066 VL - 7 SP - Articel 66 AN - OPUS4-50682 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hu, W.-H. A1 - Xu, Z.-M. A1 - Liu, M.-Y. A1 - Tang, D.-H. A1 - Lu, W. A1 - Li, Z.-H. A1 - Teng, J. A1 - Han, X.-H. A1 - Said, Samir A1 - Rohrmann, R. G. T1 - Estimation of the Lateral Dynamic Displacement of High-Rise Buildings underWind Load Based on Fusion of a Remote Sensing Vibrometer and an Inclinometer N2 - This paper proposes a novel method to estimate the lateral displacement of high-rise structures under wind loads. The coefficient β(x) is firstly derived, reflecting the relation between the structural lateral dynamic displacement and the inclination angle at the height x of a structure. If the angle is small, it is the ratio between the structural fundamental mode shape and its first-order derivative without influence of external loads. Several dynamic experiments of structures are performed based on a laser remote sensing vibrometer and an inclinometer, which shows that the fundamental mode is dominated in the structural displacement response under different types of excitations. Once the coefficient β(x) is curve-fitted by measuring both the structural lateral dynamic displacement and the inclination angle synchronously, the real-time structural lateral displacement under operational conditions is estimated by multiplying the coefficient β(x) with the inclination angle. The advantage of the proposed method is that the coefficient β(x) can be identified by lateral dynamic displacement measured in high resolution by the remote sensing vibrometer, which is useful to reconstruct the displacement accurately by the inclination angle under operational conditions KW - Inclination angle KW - High-rise building KW - Lateral dynamic displacement KW - Remote sensing vibrometer PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506833 DO - https://doi.org/10.3390/rs12071120 VL - 12 IS - 7 SP - 1120 PB - MDPI CY - 4052 Basel, Schweiz AN - OPUS4-50683 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Söftje, M. A1 - Acker, S. A1 - Plarre, Rüdiger A1 - Namyslo, J. C. A1 - Kaufmann, D. E. T1 - Novel nicotinoid structures for covalent modification of wood: an environmentally friendly way for its protection against insects N2 - Timber is constantly exposed to environmental influences under outdoor conditions which limits its Lifetime and usability. In order to counteract the damaging processes caused by insects, we have developed a novel and more environmentally friendly method to protect wood materials via covalent modification by organic insecticides. Starting with an important class of synthetic insecticides which are derived from the natural insecticide nicotine, various new carboxylic acid derivatives of imidacloprid were made accessible. These activated neonicotinoids were utilized for the chemical modification of wood hydroxy groups. In contrast to conventional wood preservation methods in which biocides are only physically bound to the surface for a limited time, the covalent fixation of the preservative guarantees a permanent effect against wood pests, demonstrated in standardized biological tests. Additionally, the environmental interaction caused by non-bound neonicotinoids is significantly reduced, since both, a smaller application rate is required and leaching of the active ingredient is prevented. By minimizing the pest infestation, the lifetime of the material increases while preserving the natural appearance of the material. KW - Environment KW - Wood Protection KW - Efficacy KW - Insecticide PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506856 DO - https://doi.org/10.1039/d0ra02071k VL - 10 SP - 15726 EP - 15733 AN - OPUS4-50685 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chinellato, Fabio A1 - Wilbig, Janka A1 - Al-Sabbagh, Dominik A1 - Colombo, P. A1 - Günster, Jens T1 - Gas flow assisted powder deposition for enhanced flowability of fine powders: 3D printing of alpha-tricalcium phosphate N2 - The possibility of creating patient-specific individual implants makes Additive Manufacturing technologies of special interest for the medical sector. For substitution of bone defects, powder based Additive Manufacturing by Binder Jetting is a suitable method to produce complex scaffold-like structures made of bioceramics with easily adapted geometries and controlled porosity. The process inherent residual porosity in the printed part, even though desired as it supports bone ingrowth, also leads to limited mechanical strength. Currently, bioceramic scaffolds made by Binder Jetting feature suitable biocompatible and biodegradable properties, while a sufficient mechanical stability is rather challenging. The purpose of this work is to apply the gas flow assisted powder deposition introduced in 2014 by Zocca et al., to the powder bed during printing of bioceramic tablets and scaffolds using α-TCP powder as feedstock. This enables exploiting the advantages of an increased powder bed density, thereby improving the mechanical properties of the printed parts. KW - Additive Manufacturing KW - Binder Jetting KW - Gas flow assisted powder deposition KW - Alpha-tricalcium phosphate KW - Scaffold PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510138 DO - https://doi.org/10.1016/j.oceram.2020.100003 SN - 2666-5395 VL - 1 SP - 100003 PB - Elsevier Ltd. AN - OPUS4-51013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Laquai, René A1 - Müller, Bernd R. A1 - Schneider, J. A1 - Kupsch, Andreas A1 - Bruno, Giovanni T1 - Using SXRR to Probe the Nature of Discontinuities in SLM Additive Manufactured Inconel 718 Specimens N2 - The utilization of additive manufacturing (AM) to fabricate robust structural components relies on understanding the nature of internal anomalies or discontinuities, which can compromise the structural integrity. While some discontinuities in AM microstructures stem from similar mechanisms as observed in more traditional processes such as casting, others are unique to the AM process. Discontinuities in AM are challenging to detect, due to their submicron size and orientation dependency. Toward the goal of improving structural integrity, minimizing discontinuities in an AM build requires an understanding of the mechanisms of formation to mitigate their occurrence. This study utilizes various techniques to evaluate the shape, size, nature and distribution of discontinuities in AM Inconel 718, in a non-hot isostatic pressed (HIPed) as-built, non-HIPed and direct age, and HIPed with two step age samples. Non-destructive synchrotron radiation refraction and transmission radiography (SXRR) provides additional information beyond that obtained with destructive optical microscopy. SXRR was able to distinguish between voids, cracks and lack of melt in, due to its sensitivity to the orientation of the discontinuity. KW - Additive manufacturing KW - X-ray refraction radiography KW - INCONEL 718 KW - Selective laser melting PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509836 DO - https://doi.org/10.1007/s11661-020-05847-5 SN - 1543-1940 VL - 51 IS - 8 SP - 4146 EP - 4157 PB - Springer AN - OPUS4-50983 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fahrbach, M. A1 - Friedrich, Sebastian A1 - Cappella, Brunero A1 - Peiner, Erwin T1 - Calibrating a high-speed contact-resonance profilometer N2 - A European EMPIR project, which aims to use large-scale piezoresistive microprobes for contact resonance applications, a well-established measurement mode of atomic force microscopes (AFMs), is being funded. As the probes used in this project are much larger in size than typical AFM probes some of the simplifications and assumptions made for AFM probes are not applicable. This study presents a guide on how to systematically create a model that replicates the dynamic behavior of microprobes, including air damping, nonlinear sensitivities, and frequency dependencies. The model is then verified by analyzing a series of measurements. KW - Piezoresistive cantilever KW - AFM KW - contact resonance PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-509899 DO - https://doi.org/10.5194/jsss-9-179-2020 VL - 9 SP - 179 EP - 187 PB - Copernicus Publications AN - OPUS4-50989 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erdmann, Maren A1 - Kleinbub, Sherin A1 - Wachtendorf, Volker A1 - Schütter, Jan David A1 - Niebergall, Ute A1 - Böhning, Martin A1 - Koerdt, Andrea T1 - Photo-oxidation of PE-HD affecting polymer/fuel interaction and bacterial attachment N2 - In the present study, a simple approach was used to investigate the effect of UV-exposure on two high density Polyethylene materials (PE-HD), commonly used for storage tanks, on fuel sorption behavior and colonization by microorganisms. The aim was to investigate whether the sorption behavior of the fuels (diesel/biodiesel) and the colonization by microorganisms, frequently occurring in the fuel, is affected and may lead to undesirable or safety-relevant material changes. We showed that the UV-irradiation leads to significant changes of the sorption behavior due to chemi-crystallization and crosslinking. The fuel Sorption is affected by the UV-induced formation of polar carbonyl and hydroxyl groups predominantly occurring at the surface. With respect to microbial colonization behavior for Bacillus subtilis and Pseudomonas aeruginosa, isolated from a contaminated diesel sample, differences of the initial adhesion could be shown depending on the initial type of polyethylene as well as on the degree of UV-induced degradation. KW - High density polyethylene KW - Bacterial attachment KW - UV-irradiation KW - Fuel sorption PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510001 DO - https://doi.org/10.1038/s41529-020-0122-1 VL - 4 IS - 1 SP - Article number: 18 PB - Nature Partner Journals AN - OPUS4-51000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Melo Bernardino, Raphael A1 - Valentino, S. A1 - Franchin, G. A1 - Günster, Jens A1 - Zocca, Andrea T1 - Manufacturing of ceramic components with internal channels by a novel additive/subtractive hybridizazion process N2 - A new approach for fabrication of ceramic components with inner channels is proposed, as a result of the combination of two additive and one subtractive manufacturing processes. In this project, porcelain parts are manufactured by the Layerwise Slurry Deposition (LSD) process, meanwhile end milling and Direct Ink Writing (DIW) are applied to create channels on the surface of the deposited ceramic. Unique to the LSD process is the Formation of a freestanding powder bed with a mechanical strength comparable to conventional slip casted ceramic green bodies. Combining these three processes allows the manufacturing of ceramic objects containing an internal path of ink, which in this case was a graphite-based ink that can be further eliminated by heat treatment to obtain a porcelain object embedded with channels. The results show the capabilities of this method and its potential to fabricate not only parts with inner channels, but also multi-material and multi-functional components (such as integrated electronic circuits). KW - Additive Manufacturing KW - Layerwise Slurry Deposition KW - Hybrid Manufacturing PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510012 UR - https://www.sciencedirect.com/science/article/pii/S2666539520300109?via%3Dihub DO - https://doi.org/10.1016/j.oceram.2020.100010 VL - 2 SP - 100010 PB - Elsevier Ltd. AN - OPUS4-51001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tantardini, C. A1 - Michalchuk, Adam A1 - Samtsevich, A. A1 - Rota, C. A1 - Kvashnin, A. G. T1 - The Volumetric Source Function: Looking Inside van der Waals Interactions N2 - The study of van der Waals interactions plays a central role in the understanding of bonding across a range of biological, chemical and physical phenomena. The presence of van der Waals interactions can be identified through analysis of the reduced density gradient, a fundamental parameter at the core of Density Functional Theory. An extension of Bader’s Quantum Theory of Atoms in Molecules is developed here through combination with the analysis of the reduced density gradient. Through this development, a new quantum chemical topological tool is presented: the volumetric source function. This technique allows insight into the atomic composition of van der Waals interactions, offering the first route towards applying the highly successful source function to these disperse interactions. A new algorithm has been implemented in the open-source code, CRITIC2, and tested on acetone, adipic and maleic acids molecular crystals, each stabilized by van der Waals interactions. This novel technique for studying van der Waals interactions at an atomic level offers unprecedented opportunities in the fundamental study of intermolecular interactions and molecular design for crystal engineering, drug design and bio-macromolecular processes. KW - Noncovalent interactions PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507911 DO - https://doi.org/10.1038/s41598-020-64261-4 VL - 10 IS - 1 SP - 7816 AN - OPUS4-50791 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Borghetti, P. A1 - Ortel, Erik A1 - Wirth, Thomas A1 - Garcia, S. A1 - Gómez, E. A1 - Blanco, M. A1 - Alberto, G. A1 - Martra, G. T1 - Organic surface modification and analysis of titania nanoparticles for self‐assembly in multiple layers N2 - The characteristics of TiO2 coatings can greatly influence their final performance in large‐scale applications. In the present study, self‐assembly of TiO2 nanoparticles (NPs) in multiple layers was selected as a deposition procedure on various substrates. For this, the main prerequisite constitutes the surface modification of both NPs and substrate with, for example, silane coupling agents. A set of functionalized TiO2 NPs has been produced by reaction with either (3‐aminopropyl)triethoxysilane (APTES) or (3‐aminopropyl)phosphonic acid (APPA) to functionalize the NP surface with free amino‐groups. Then, the complementary functionalized NP set can be obtained from an aliquot of the first one, through the conversion of free surface amino groups to aldehydes by reaction with glutaraldehyde (GA). Several types of TiO2 NPs differing in size, shape, and specific surface area have been functionalized. Fourier‐transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), SEM/ energy‐dispersive X‐ray spectroscopy (EDS), XPS, Auger electron spectroscopy (AES), and Time‐of‐Flight (ToF)‐SIMS analyses have been carried out to evaluate the degree of functionalization, all the analytical methods employed demonstrating successful functionalization of TiO2 NP surface with APTES or APPA and GA. KW - TiO2 KW - Nanoparticles KW - Surface functionalization KW - Layer-by-layer deposition KW - Surface chemical analysis PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508601 DO - https://doi.org/10.1002/sia.6842 SN - 1096-9918 VL - 52 IS - 12 SP - 829 EP - 834 PB - John Wiley & Sons Ltd AN - OPUS4-50860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krahl, T. A1 - Beer, F. A1 - Relling, A. A1 - Gawlitza, Kornelia A1 - Rurack, Knut A1 - Kemnitz, E. T1 - Toward Luminescent Composites by Phase Transfer of SrF2 :Eu3+ Nanoparticles Capped with Hydrophobic Antenna Ligands N2 - Transparent dispersions of hydrophobic SrF2 :Eu3+ nanoparticles in cyclohexane with up to 20% europium were obtained by fluorolytic sol-gel synthesis followed by Phase transfer into cyclohexane through capping with sodium dodecylbenzenesulfonate (SDBS). The particles were characterized by TEM, XRD and DLS as spherical objects with a diameter between 6 and 11 nm in dry state. 1H-13CP MAS NMR experiments revealed the binding of the anionic sulfonate head group to the particle surface. The particles show bright red luminescence upon excitation of the aromatic capping agents, acting as antennas for an Energy transfer from the benzenesulfonate unit to the Eu3+ centers in the particles. This synthesis method overcomes the current obstacle of the fluorolytic sol-gel synthesis that transparent dispersions can be obtained directly only in hydrophilic solvents. To demonstrate the potential of such hydrophobized alkaline-earth fluoride particles, transparent luminescent organic-inorganic composites with 10% SrF2 :Eu3+ embedded into polyTEGDMA, polyBMA, poly-BDDMA and polyD3MA, respectively, were prepared, endowing the polymers with the luminescence features of the nanoparticles. KW - Nanoparticles KW - Fluorides KW - Sol-gel process KW - Organic-inorganic hybrid composites PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508668 DO - https://doi.org/10.1002/cnma.202000058 SP - 1 EP - 11 PB - Wiley AN - OPUS4-50866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Long, Lijia A1 - Döhler, M. A1 - Thöns, Sebastian T1 - Determination of structural and damage detection system influencing parameters on the value of information N2 - A method to determine the influencing parameters of a structural and damage detection system is proposed based on the value of Information analysis. The value of information analysis utilizes the Bayesian pre-posterior decision theory to quantify the value of damage detection system for the structural integrity management during service life. First, the influencing parameters of the structural system, such as deterioration type and rate are introduced for the performance of the prior probabilistic system model. Then the influencing parameters on the damage detection system performance, including number of sensors, sensor locations, measurement noise, and the Type-I error are investigated. The preposterior probabilistic model is computed utilizing the Bayes’ theorem to update the prior system model with the damage indication information. Finally, the value of damage detection system is quantified as the difference between the maximum utility obtained in pre-posterior and prior analysis based on the decision tree analysis, comprising structural probabilistic models, consequences, as well as benefit and costs analysis associated with and without monitoring. With the developed approach, a case study on a statically determinate Pratt truss bridge girder is carried out to validate the method. The analysis shows that the deterioration rate is the most sensitive parameter on the effect of relative value of information over the whole service life. Furthermore, it shows that more sensors do not necessarily lead to a higher relative value of information; only specific sensor locations near the highest utilized components lead to a high relative value of information; measurement noise and the Type-I error should be controlled and be as small as possible. An optimal sensor employment with highest relative value of information is found. Moreover, it is found that the proposed method can be a powerful tool to develop optimal service life maintenance strategies—before implementation—for similar bridges and to optimize the damage detection system settings and sensor configuration for minimum expected Costs and risks. KW - Damage detection systems KW - Value of information KW - Deteriorating structures KW - Probability of damage indication KW - Decision theory PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508083 DO - https://doi.org/10.1177/1475921719900918 SN - 1475-9217 SN - 1741-3168 VL - 21 IS - 1 SP - 19 EP - 36 PB - Sage Publications CY - Thousand Oaks, Calif. AN - OPUS4-50808 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hoffmann, Katrin A1 - Nirmalananthan-Budau, Nithiya A1 - Resch-Genger, Ute T1 - Fluorescence calibration standards made from broadband emitters encapsulated in polymer beads for fluorescence microscopy and flow cytometry N2 - We present here the design and characterization of a set of spectral calibration beads. These calibration beads are intended for the determination and regular control of the spectral characteristics of fluorescence microscopes and other fluorescence measuring devices for the readout of bead-based assays. This set consists of micrometer-sized polymer beads loaded with dyes from the liquid Calibration Kit Spectral Fluorescence Standards developed and certified by BAM for the wavelength-dependent Determination of the spectral responsivity of fluorescencemeasuring devices like spectrofluorometers. To cover the wavelength Region from 400 to 800 nm, two new near-infrared emissive dyes were included, which were spectroscopically characterized in solution and encapsulated in the beads. The resulting set of beads presents the first step towards a new platform of spectral calibration beads for the determination of the spectral characteristics of fluorescence instruments like fluorescence microscopes, FCM setups, and microtiter plate readers, thereby meeting the increasing demand for reliable and comparable fluorescence data especially in strongly regulated areas, e.g., medical diagnostics. This will eventually provide the basis for standardized calibration procedures for imaging systems as an alternative to microchannel slides containing dye solutions previously reported by us. KW - Fluorescence standard KW - Fluorescence KW - Dye KW - Microscopy KW - Bead KW - Particle KW - NIR KW - calibration KW - Quality assurance KW - Traceability PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508117 DO - https://doi.org/10.1007/s00216-020-02664-y SN - 1618-2642 VL - 412 IS - 24 SP - 6499 EP - 6507 PB - Springer AN - OPUS4-50811 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kervarec, M.-C. A1 - Kemnitz, E. A1 - Scholz, G. A1 - Rudic, S. A1 - Jäger, Christian A1 - Braun, T. A1 - Michalchuk, Adam A1 - Emmerling, Franziska T1 - A HF Loaded Lewis-Acidic Aluminium Chlorofluoride for Hydrofluorination Reactions N2 - The very strong Lewis acid aluminium chlorofluo-ride (ACF) was loaded with anhydrous HF. The interactionbetween the surface of the catalyst and HF was investigatedusing a variety of characterization methods, which revealed he formation of polyfluorides. Moreover, the reactivity ofthe HF-loaded ACF towards the hydrofluorination of alkyneswas studied. KW - Aluminium KW - HF KW - Hydrofluorination KW - Metal fluorides PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508360 DO - https://doi.org/10.1002/chem.202001627 VL - 26 SP - 1 PB - Wiley Online Libary AN - OPUS4-50836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Usmani, Shirin M. A1 - Plarre, Rüdiger A1 - Hübert, Thomas A1 - Kemnitz, E. T1 - Termite resistance of pine wood treated with nano metal fluorides N2 - Fluorides are well-known as wood preservatives. One of the limitations of fluoride-based wood preservatives is their high leachability. Alternative to current fluoride salts such as NaF used in wood protection are low water-soluble fluorides. However, impregnation of low water-soluble fluorides into wood poses a challenge. To address this challenge, low water-soluble fluorides like calcium fluoride (CaF2) and magnesium fluoride (MgF2) were synthesized as nanoparticles via the fluorolytic sol−gel synthesis and then impregnated into wood specimens. In this study, the toxicity of nano metal fluorides was assessed by termite mortality, mass loss and visual analysis of treated specimens after eight weeks of exposure to termites, Coptotermes formosanus. Nano metal fluorides with sol concentrations of 0.5 M and higher were found to be effective against termites resulting in 100% termite mortality and significantly inhibited termite feeding. Among the formulations tested, the least damage was found for specimens treated with combinations of CaF2 and MgF2 with an average mass loss less than 1% and visual rating of “1”. These results demonstrate the efficacy of low water-soluble nano metal fluorides to protect Wood from termite attack. KW - Wood Protection KW - Nano Particles KW - Termites PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508377 DO - https://doi.org/10.1007/s00107-020-01522-z VL - 78 SP - 493 EP - 499 PB - Springer AN - OPUS4-50837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reichelt, Manuel A1 - Cappella, Brunero T1 - Comparative analysis of error sources in the determination of wear volumes of oscillating ball-on-plane tests N2 - The accurate determination of wear volumes is a prerequisite for the study of numerous tribological phenomena. Wear volumes can be measured with different techniques or else be calculated starting from some quantities measured from the wear scar. Advantages and drawbacks of the measuring techniques are shown by means of wear scars and calottes resulting from ball-on-plane tests with 100Cr6 specimens. When measuring wear volumes, white light interferometry results to be one of the most suitable techniques. When wear volumes are calculated, errors result mainly from two sources: (1) the arbitrary choice of one or few line profiles for the determination of the width and of the planimetric wear, and (2) approximations in the calculation, which are even necessary when values of the wear volumes of the single tribological partners and not only the total volume are of interest. The effect of both error sources on the accuracy in the determination of wear volumes is characterized and elucidated by examples. It is found that errors due to approximations are negligible when compared to errors due to the arbitrary choice of one line profile. KW - Error sources analysis KW - White light interferometry KW - Statistical analysis KW - AFM KW - Wear KW - Oscillating ball-on-disc test PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-508407 DO - https://doi.org/10.3389/fmech.2020.00025 VL - 6 SP - Article 25 AN - OPUS4-50840 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dittmann, Daniel A1 - Eisentraut, Paul A1 - Goedecke, Caroline A1 - Wiesner, Yosri A1 - Jekel, M A1 - Ruhl, A S A1 - Braun, Ulrike T1 - Specific adsorption sites and conditions derived by thermal decomposition of activated carbons and adsorbed carbamazepine N2 - The adsorption of organic micropollutants onto activated carbon is a favourable solution for the treatment of drinking water and wastewater. However, these adsorption processes are not sufficiently understood to allow for the appropriate prediction of removal processes. In this study, thermogravimetric analysis, alongside evolved gas analysis, is proposed for the characterisation of micropollutants adsorbed on activated carbon. Varying amounts of carbamazepine were adsorbed onto three different activated carbons, which were subsequently dried, and their thermal decomposition mechanisms examined. The discovery of 55 different pyrolysis products allowed differentiations to be made between specific adsorption sites and conditions. However, the same adsorption mechanisms were found for all samples, which were enhanced by inorganic constituents and oxygen containing surface groups. Furthermore, increasing the loadings led to the evolution of more hydrated decomposition products, whilst parts of the carbamazepine molecules were also integrated into the carbon structure. It was also found that the chemical composition, especially the degree of dehydration of the activated carbon, plays an important role in the adsorption of carbamazepine. Hence, it is thought that the adsorption sites may have a higher adsorption energy for specific adsorbates, when the activated carbon can then potentially increase its degree of graphitisation. KW - Aktivkohle KW - TED-GC/MS KW - Adsorption KW - Thermoanalytik PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506946 DO - https://doi.org/10.1038/s41598-020-63481-y VL - 10 IS - 1 SP - 6695 PB - Nature Publishing Group AN - OPUS4-50694 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kanwal, S. A1 - Ali, Naveed Zafar A1 - Hussain, R. A1 - Shah, F.U. A1 - Akhter, Z. T1 - Poly-thiourea formaldehyde based anticorrosion marine coatings on Type 304 stainless steel N2 - In the present study, hexamethylene diisocyanate (HMDI) encapsulated poly-thiourea formaldehyde (PTF) (10 wt%) coating was developed in an epoxy-polyamine matrix and their anticorrosion studies on Type SS304 stainless steel substrate have been conducted using electrochemistry techniques. The compact and hydrophobic shell wall of PTF proved to be a potent shell wall material for HMDI encapsulation. The effect of temperature and pH values was found to be decisive factor in the synthesis of microcapsules. The PTF microcapsules were synthesized in acidic condition with a pH value of 3. Over 90% of the core fraction is retained in water after 21 days immersion. However, core content decreased with increasing temperature. The capsules were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Electrochemical Impedance spectroscopy (EIS). Scanning electron microscopic analysis depicts the uniform morphology of coating with a particle size in the range of 1.08 µm–22.06 µm. The vibrational band at 2271 cm−1 attributed to NCO signal further endorses the successful encapsulation of HMDI into the PTF capsules. Electrochemical testing on steel specifies the appreciable anticorrosion performance of the synthesized poly thiourea formaldehyde (PTF) coating against artificial sea water. KW - In-situ polymerization KW - Encapsulation KW - Thiourea-formaldehyde KW - Marine corrosion PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507932 DO - https://doi.org/10.1016/j.jmrt.2019.12.045 VL - 9 IS - 2 SP - 2146 EP - 2153 PB - Elsevier B.V. AN - OPUS4-50793 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Birgit Angelika A1 - Ziemann, M. A A1 - Pentzien, Simone A1 - Gabsch, T. A1 - Koch, W. A1 - Krüger, Jörg T1 - Technical analysis of a Central Asian wall painting detached from a Buddhist cave temple on the northern Silk Road N2 - A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhöhle). Its original painted surface is soot blackened and largely illegible. Grünwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified. KW - Wall paintings KW - Central Asia KW - Silk Road KW - Pigments KW - Microscopy PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-357297 DO - https://doi.org/10.1179/2047058414Y.0000000152 VL - 61 IS - 2 SP - 113 EP - 122 PB - Routledge Taylor & Francis Group CY - London AN - OPUS4-35729 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hosseini, Seyed M.H. A1 - Ségur, D. A1 - Boehm, Rainer A1 - Gohlke, Dirk A1 - Heckel, Thomas A1 - Riemer, S. A1 - Brackrock, Daniel A1 - Gaal, Mate T1 - Characterization and optimization of ultrasonic tests for inspection of fiber-reinforced plastic composites in energy related applications N2 - Applications of fibre reinforced plastic (FRP) composites in modern industries are increasing due to their considerable advantages such as light weight and excellent mechanical properties. Accordingly, importance of operational safety of modern structures made of advanced composites by ensuring the material quality has led to increasing demands for development of non-destructive evaluation (NDE) systems. In the context of a European project entitled “Validated Inspection Techniques for Composites in Energy Applications” (VITCEA), the aim is to develop and validate traceable procedures for novel NDE techniques with contrasting damage detection capabilities in energy related applications such as wind and marine turbine blades, nacelles, oil and gas flexible risers. Accordingly, VITCEA focuses on optimization of ultrasonic tests (UTs) for quantitative defect detection and quality characterization of FRP structures. In this context, the present study describes the ultrasound field in heterogeneous composite materials. The theoretical predictions are compared with simulation results obtained from CIVA a software package dedicated to NDT simulations based on the asymptotic ray theory. T2 - WCNDT 2016 - - 19th World Conference on Non-Destructive Testing CY - München DA - 13.06.2016 KW - Ultrasonic tests KW - Composite KW - Wave propagation KW - Analytical approach PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-356398 SP - We.4.D.5, 1 EP - 8 AN - OPUS4-35639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Konersmann, Rainer T1 - Überdeckungshöhen von Pipelines - Wie tief ist tief genug? N2 - Ein wesentliches Grundbedürfnis ist die Sicherheit, d. h. die Gewissheit, in einer sicheren Umgebung zu leben und zu arbeiten. Die existenzielle Sicherheit ist eine notwendige Voraussetzung zur Befriedigung aller weiteren notwendigen Bedürfnisse. Auch die Technik ist ohne Sicherheit nicht denkbar. Trotz aller Bemühungen kommt es aber immer wieder zu Unfällen, aus welchen Gründen auch immer. Eine Strategie, Unfälle zu verhindern bzw. deren Eintrittswahrscheinlichkeit zu minimieren ist es, zwischen einem Objekt mit einem hohen Gefährdungspotenzial und seiner Nachbarschaft, Barrieren zu errichten, z. B. durch eine schützende Isolierung, Sicherheitsabstände oder durch eine Erdüberdeckung. Die erdgedeckte Verlegung von Pipelines ist Stand der Technik. Über die Überdeckungshöhen scheint es jedoch verschiedene Auffassungen zu geben. Im folgenden Beitrag werden dazu einige Beispiele vorgestellt. KW - Rohrleitungen KW - optimale Überdeckungshöhe KW - Verkehrslasten PY - 2016 SN - 2191-0073 VL - 36 IS - 3 SP - 44 EP - 48 PB - Springer-VDI-Verl. CY - Düsseldorf AN - OPUS4-35681 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Andres, S. A1 - Hansen, Ulf A1 - Niemann, B. A1 - Palavinskas, R. A1 - Lampen, A. T1 - Determination of the isoflavone composition and estrogenic activity of commercial dietary supplements based on soy or red clover N2 - Dietary supplements high in isolated isoflavones are commercially available for human consumption primarily to alleviate menopausal symptoms in women. The isoflavone composition, quantity and importantly their estrogenic potency are poorly standardised and can vary considerably between different products. The aim of this study was to analyse the isoflavone composition of 11 dietary supplements based on soy or red clover using the HPLC/MS/MS technique. Furthermore, we investigated the transactivational potential of the supplements on the estrogen receptors (ER), ERα and ERβ, performing luciferase reporter gene assays. As expected, we found that the isoflavone composition varies between different products. The measured total isoflavone contents in various supplements were mostly comparable to those claimed by the manufacturers in their product information. However expressing the isoflavone content as isoflavone aglycone equivalents, soy-based supplements had a clearly lower quantity compared to the manufacturer information. All supplements transactivated more or less ERα and ERβ with a preference for ERβ. The transactivational efficiency exceeded partly the maximal 17β-estradiol induced ER activation. While the different soy-based supplements revealed similar transactivation potential to both ERs, red clover-based supplements differed considerably. We conclude that different commercial dietary supplements based on soy or red clover vary in their isoflavone composition and quantity. They are estrogenically active, although especially the red clover-based supplements show considerable differences in their estrogenic potential to ERα and ERβ. Thus, different isoflavone-rich products cannot be necessarily compared regarding possible biological effects. KW - estrogenic activity KW - HPLC/MS/MS technique KW - Estrogen receptor (ER) KW - nutritional supplements PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-357093 DO - https://doi.org/10.1039/C5FO00308C IS - 6 SP - 2017 EP - 2025 PB - The Royal Soc. of Chemistry CY - Cambridge AN - OPUS4-35709 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Armatys, Kamila A1 - Miller, M. T1 - Knudsen effusion mass spectrometry studies on metal halides performed in 1990-2014 N2 - Abstract Investigations on metal halide systems carried out by Knudsen effusion mass spectrometry in the period 1990-2014 are reviewed in the present paper.163 original papers were published focused on metal halides showing still considerable activity in this area. The fundamentals of the Knudsen effusion mass spectrometry method and thermodynamic background of the investigation are briefly reported. Data to the system studied, temperature ranges, Knudsen cell materials, vapor species identified in the equilibrium vapors and the thermodynamic properties obtained in the study are presented. The important issues of metal halide vaporization studies are briefly discussed and commented. The studies of the vaporization of metal halogens by Knudsen effusion mass spectrometry aimed firstly atthe determination of gaseous complexes species in the vapor and determination of its thermodynamic data like sublimation enthalpy etc. and secondly at the determination of negative ions formation and various ion-molecule equilibria reactions of metal halide systems. Many of the studied materials have a crucial role for modern technologies, for example metal halide lamps, hot corrosion caused by halide salts, phosphorus recovery technologies or gas assisted separation of lanthanides. The investigation of such systems gives information on mechanisms of vaporization, volatility of the systems under various conditions (temperature, pressure etc.), reactivity, thermal stability, resistance etc. that could be further applied for various calculations and to predict the behavior of various components under various technological aspects. KW - Metal halides KW - Knudsen Effusion Mass Spectrometry (KEMS) KW - HTMS KW - Thermochemistry KW - High temperature KW - Vaporization PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-357126 SN - 2349-7092 VL - 3 IS - 1 SP - 68 EP - 93 PB - The Pharmaceutical and Chemical Journal CY - Kundlawala, India AN - OPUS4-35712 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schadow, Florian A1 - Gaal, Mate A1 - Bartusch, Jürgen A1 - Dohse, E. A1 - Köppe, Enrico T1 - Focusing air-coupled ultrasonic transducers based on ferroelectrets N2 - Rising importance of composite lightweight structures in aircraft and automobile industries increases the demand on reliable non-destructive testing methods for these structures. Air-coupled ultrasonic testing emerged to suit these requirements as it does not require any liquid coupling medium. In conventional air-coupled ultrasonic transducers, matching layers are used in order to decrease the impedance mismatch between transducer and air. Matching layers can be omitted by using ferroelectrets, which are charged cellular polymers having ferroelectric and piezoelectric properties. Especially a low Young’s modulus, low density and low sound velocity of cellular polypropylene (cPP) are properties being required for well-matched air-coupled ultrasonic transducers. In our contribution we show recent enhancements of cPP transducers resulting in focused sound fields and thus improved lateral sensitivity. The influence of different transmitter apertures was evaluated using measurements of the emitted sound field. Further we show a transmission of a test specimen of carbon-fiber-reinforced plastic (CFRP) containing artificial damages. Results of focused transducers were compared to planar ferroelectret transducers, as well as to conventional air-coupled transducers. T2 - 19th World Conference on Non-Destructive Testing 2016 CY - München, Germany DA - 13.06.2016 KW - Air-coupled ultrasonic testing KW - Ferroelectrets KW - Cellular polypropylene KW - Focused sound fields KW - Focused transducers PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355116 UR - http://www.ndt.net/search/docs.php3?showForm=off&id=19453 SP - 1 EP - 8 AN - OPUS4-35511 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wilke, Manuel A1 - Klimakow, Maria A1 - Rademann, K. A1 - Emmerling, Franziska T1 - Fast and efficient synthesis of a host guest system: a mechanochemical approach N2 - An unusually fast and effective synthesis procedure for a host guest system consisting of a metal organic framework (MOF) and a polyoxometalate (POM) is described. The material was synthesised mechanochemically and the evolution of the structure was monitored ex and in situ using synchrotron X-ray diffraction (XRD). KW - Mechanochemistry KW - MOF KW - in situ PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-354910 UR - http://pubs.rsc.org/en/Content/ArticleLanding/2016/CE/C5CE01868D#!divAbstract DO - https://doi.org/10.1039/C5CE01868D VL - 18 IS - 7 SP - 1096 EP - 1100 AN - OPUS4-35491 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fasano, A. A1 - Woyessa, G. A1 - Stajanca, Pavol A1 - Markos, C. A1 - Stefani, A. A1 - Nielsen, K. A1 - Rasmussen, H. K. A1 - Krebber, Katerina A1 - Bang, O. T1 - Fabrication and characterization of polycarbonate microstructured polymer optical fibers for high-temperature-resistant fiber Bragg grating strain sensors N2 - Here we present the fabrication of a solid-core microstructured polymer optical fiber (mPOF) made of polycarbonate (PC), and report the first experimental demonstration of a fiber Bragg grating (FBG) written in a PC optical fiber. The PC used in this work has a glass transition temperature of 145°C. We also characterize the mPOF optically and mechanically, and further test the sensitivity of the PC FBG to strain and temperature. We demonstrate that the PC FBG can bear temperatures as high as 125°C without malfunctioning. In contrast, polymethyl methacrylate-based FBG technology is generally limited to temperatures below 90°C. KW - Fiber optics sensors KW - Fiber Bragg gratings KW - Microstructured fibers KW - Fiber characterization KW - Polymers PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355591 DO - https://doi.org/10.1364/OME.6.000649 SN - 2159-3930 VL - 6 IS - 2 SP - 649 EP - 659 PB - OSA Publishig AN - OPUS4-35559 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Rades, Steffi A1 - Salge, T. A1 - Mielke, Johannes A1 - Ortel, Erik A1 - Schmidt, R. T1 - Characterisation of nanoparticles by means of high-resolution SEM/EDS in transmission mode N2 - Advances in scanning electron microscopy (SEM) enable the high-resolution imaging of single nanoparticles (NPs) with sizes well below 10 nm. The SEM analysis in transmission mode (T-SEM) of NPs on thin film supports has many benefits when compared to the analysis of NPs on bulk substrates. The enhanced material (mass – thickness) contrast of the T-SEM imaging mode is well suited for in-depth and, particularly valuable, to very accurate, traceable, lateral dimensional measurements of NPs. Compared to samples prepared on bulk substrates, T-SEM with energy dispersive X-ray spectroscopy (EDS) achieves a drastically improved spatial resolution of the emitted X-rays. The poor signal-to-noise ratio of the X-ray spectra emitted by a single nanoparticle (NP) can be improved by the use of high-sensitivity (high collection solid angle) silicon drift (SDD), energy-dispersive X-ray spectrometers (EDS). The EDS spectral imaging of a single NP with a spatial resolution below 10 nm has become possible. This is demonstrated by means of various examples of nanostructures. Advanced data processing of T-SEM/EDS results sets the stage for the automated classification of NPs by feature analysis. This method combines the detection of morphological structures of interest by image processing of T-SEM micrographs with the chemical classification by EDS. T2 - European Microbeam Analysis Society’s 14th European Workshop on Modern Developments and Applications in Microbeam Analysis (EMAS 2015) CY - Portorož, Slovenia DA - 03.05.2015 KW - High-resolution KW - SEM KW - T-SEM KW - EDX KW - Nanoparticles PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355628 UR - http://iopscience.iop.org/article/10.1088/1757-899X/109/1/012006 DO - https://doi.org/10.1088/1757-899X/109/1/012006 SN - 1757-899X VL - 109 SP - 012006-1 EP - 012006-12 PB - IOP Publishing Ltd CY - Bristol, UK AN - OPUS4-35562 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dmitriev, A. I. A1 - Österle, Werner ED - Österle, Werner ED - Zhang, G. T1 - The role of solid lubricants for brake friction materials N2 - This review article comprises of three parts. Firstly, reports of brake manufacturers on the beneficial impact of solid lubricants for pad formulations are surveyed. Secondly, since tribofilms were identified to play a crucial role in friction stabilization and wear reduction, the knowledge about tribofilm structures formed during automotive braking was reviewed comprehensively. Finally, a model for simulating the sliding behavior of tribofilms is suggested and a review on modelling efforts with different model structures related to real tribofilms will be presented. Although the variety of friction composites involved in commercial brake systems is very broad, striking similarities were observed in respect to tribofilm nanostructures. Thus a generalization of the tribofilm nanostructure is suggested and prerequisites for smooth sliding performance and minimal wear rates have been identified. A minimum of 13 vol.% of soft inclusions embedded in an iron oxide based tribofilm is crucial for obtaining the desired properties. As long as the solid lubricants or their reaction products are softer than magnetite, the main constituent of the tribofilm, the model predicts smooth sliding and a minimum of wear. KW - Solid lubricant KW - Friction KW - Automotive braking KW - Tribofilm KW - Sliding simulation KW - MCA-modeling PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355973 UR - www.mdpi.com/journal/lubricants DO - https://doi.org/10.3390/lubricants4010005 SN - 2075-4442 VL - 4 IS - 1 SP - 5 EP - 26 PB - MDPI CY - Basel, Switzerland AN - OPUS4-35597 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lehmann, Jens A1 - Burkert, Andreas T1 - KorroPad - Beurteilung der Korrosionsbeständigkeit von Oberflächen nichtrostender Stähle N2 - Mit dem KorroPad Verfahren ist es dem Anwender möglich den Zustand der Passivschicht nichtrostender Stähle auf sehr einfache und schnelle Weise einschätzen zu können. Das Verfahren eignet sich dazu, den Grad der Passivität in Abhängigkeit der Umgebungsbedingungen und der Zeit nachzuvollziehen. Dies ermöglicht dem Anwender und Verarbeiter von nichtrostenden Stählen, die Lagerungsbedingungen und –zeiten einer frisch bearbeiteten Stahloberfläche zu ermitteln, welche für die Ausbildung einer stabilen Passivschicht notwendig sind, bevor diese risikoarm eingesetzt werden kann. Wie die hier dargestellten Beispiele und auch weitere zahlreiche praktische Anwendungen gezeigt haben, eignet sich das KorroPad ebenfalls für die Identifikation kritischer Prozessparameter bei der Verarbeitung nichtrostender Stähle. Mit dem Verfahren lassen sich viele prozessbedingte Einflussfaktoren auf die Oberflächengüte wie auch auf den Werkstoff charakterisieren. Aufgrund der schnellen und einfachen Auswertung der Prüfergebnisse können positive wie auch negative Veränderungen hinsichtlich der Passivschichtstabilität zügig erkannt werden. Dies ermöglicht es dem Anwender schnell zu reagieren, um kritische Einflüsse zu korrigieren und um eine Optimierung von Inhouse-Prozessen durchzuführen. Weitere Einsatzgebiete sind im Bereich der Wareneingangs- und/oder Warenausgangskontrolle denkbar, überall wo es um die Frage der Passivschichtstabilität einer nichtrostenden Stahloberfläche geht. T2 - Fachtagung Bauwerksdiagnose - Praktische Anwendungen Zerstörungsfreier Prüfungen und Zukunftsaufgaben CY - Berlin, Germany DA - 25.02.2016 KW - Korrosionsschnelltest, Nichtrostender Stahl, Passivschicht, KorroPad PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355146 SN - 978-3-940283-77-1 VL - 157 SP - 1 EP - 7 PB - Deutsche Gesellschaft für zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-35514 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steinkönig, J. A1 - Bloesser, F. R. A1 - Huber, B. A1 - Welle, A. A1 - Trouillet, V. A1 - Weidner, Steffen A1 - Barner, L. A1 - Roesky, P. W. A1 - Yuan, J. A1 - Goldmann, A. S. A1 - Barner-Kowollik, C. T1 - Controlled radical polymerization and in-depth mass-spectrometric characterization of poly(ionic liquid)s and their photopatterning on surfaces N2 - The preparation and characterization of poly(ionic liquid)s (PILs) bearing a polystyrene backbone via reversible addition fragmentation chain transfer (RAFT) polymerization and their photolithographic patterning on silicon wafers is reported. The controlled radical polymerization of the styrenic ionic liquid (IL) monomers ([BVBIM]X, X = Cl− or Tf2N−) by RAFT polymerization is investigated in detail. We provide a general synthetic tool to access this class of PILs with controlled molecular weight and relatively narrow molecular weight distribution (2000 g mol−1 ≤ Mn ≤ 10 000 g mol−1 with dispersities between 1.4 and 1.3 for p([BVBIM]Cl); 2100 g mol−1 ≤ MP ≤ 14 000 g mol−1 for p([BVBIM]Tf2N)). More importantly, we provide an in-depth characterization of the PILs and demonstrate a detailed mass spectrometric analysis via matrix-assisted laser desorption ionization (MALDI) as well as – for the first time for PILs – electrospray ionization mass spectrometry (ESI-MS). Importantly, p([BVBIM]Cl) and p([DMVBIM]Tf2N) were photochemically patterned on silicon wafers. Therefore, a RAFT agent carrying a photoactive group based on ortho-quinodimethane chemistry – more precisely photoenol chemistry – was photochemically linked for subsequent controlled radical polymerization of [BVBIM]Cl and [DMVBIM]Tf2N. The successful spatially-resolved photografting is evidenced by surface-sensitive characterization methods such as X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). The presented method allows for the functionalization of diverse surfaces with poly(ionic liquid)s. KW - reversible addition fragmentation chain transfer (RAFT) polymerization KW - polyionic liquids KW - mass spectrometry KW - surface modification PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-355202 DO - https://doi.org/10.1039/C5PY01320H VL - 7 SP - 451 EP - 461 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-35520 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tamschick, S. A1 - Rozenblut-Kościsty, B. A1 - Ogielska, M. A1 - Lehmann, Andreas A1 - Lymberakis, P. A1 - Hoffmann, F. A1 - Lutz, I. A1 - Kloas, W. A1 - Stöck, M. T1 - Sex reversal assessments reveal different vulnerability to endocrine disruption between deeply diverged anuran lineages N2 - Multiple anthropogenic stressors cause worldwide amphibian declines. Among several poorly investigated causes is global pollution of aquatic ecosystems with endocrine disrupting compounds (EDCs). These substances interfere with the endocrine system and can affect the sexual development of vertebrates including amphibians. We test the susceptibility to an environmentally relevant contraceptive, the artificial estrogen 17α-ethinylestradiol (EE2), simultaneously in three deeply divergent systematic anuran families, a model-species, Xenopus laevis (Pipidae), and two non-models, Hyla arborea (Hylidae) and Bufo viridis (Bufonidae). Our new approach combines synchronized tadpole exposure to three EE2-concentrations (50, 500, 5,000 ng/L) in a flow-through-system and pioneers genetic and histological sexing of metamorphs in non-model anurans for EDC-studies. This novel methodology reveals striking quantitative differences in genetic-male-to-phenotypic-female sex reversal in non-model vs. model species. Our findings qualify molecular sexing in EDC-analyses as requirement to identify sex reversals and state-of-the-art approaches as mandatory to detect speciesspecific vulnerabilities to EDCs in amphibians. KW - Endocrine disruption KW - 17α-ethinylestradiol (EE2) KW - Mass spectrometry KW - Sex reversal PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-357797 DO - https://doi.org/10.1038/srep23825 SN - 2045-2322 VL - 6 SP - Article No. 23825, 1 EP - 8 PB - Nature publishing group AN - OPUS4-35779 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ye, S. A1 - Loll, B. A1 - Berger, A. A1 - Mülow, Ulrike A1 - Alings, C. A1 - Wahl, M. A1 - Koksch, B. T1 - Fluorine teams up with water to restore inhibitor activity to mutant BPTI N2 - Introducing fluorine into molecules has a wide range of effects on their physicochemical properties, often desirable but in most cases unpredictable. The fluorine atom imparts the C–F bond with low polarizability and high polarity, and significantly affects the behavior of neighboring functional groups, in a covalent or noncovalent manner. Here, we report that fluorine, present in the form of a single fluoroalkyl amino acid side chain in the P1 position of the well-characterized serine-protease inhibitor BPTI, can fully restore inhibitor activity to a mutant that contains the corresponding hydrocarbon side chain at the same site. High resolution crystal structures were obtained for four BPTI variants in complex with bovine b-trypsin, revealing changes in the stoichiometry and dynamics of water molecules in the S1 subsite. These results demonstrate that the introduction of fluorine into a protein environment can result in “chemical complementation” that has a significantly favorable impact on protein–protein interactions. KW - serine-protease inhibitor KW - crystal structures KW - Peptide synthesis PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-358987 DO - https://doi.org/10.1039/C4SC03227F IS - 9 SP - 5246 EP - 5254 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-35898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Matkovic, A. A1 - Vasic, B. A1 - Pesic, J. A1 - Prinz, J. A1 - Bald, Ilko A1 - Milosavljevic, A. R. A1 - Gajic, R. T1 - Enhanced structural stability of DNA origami nanostructures by graphene encapsulation N2 - Wedemonstrate that a single-layer graphene replicates the shape ofDNAorigami nanostructures very well. It can be employed as a protective layer for the enhancement of structural stability of DNA origami nanostructures. Using the AFM based manipulation, we show that the normal force required to damage graphene encapsulated DNA origami nanostructures is over an order of magnitude greater than for the unprotected ones. In addition, we show that graphene encapsulation offers protection to the DNA origami nanostructures against prolonged exposure to deionized water, and multiple immersions. Through these results we demonstrate that graphene encapsulated DNA origami nanostructures are strong enough to sustain various solution phase processing, lithography and transfer steps, thus extending the limits of DNA-mediated bottom-up fabrication. KW - atomic force microscopy KW - graphene KW - DNA origami nanostructures PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-358741 UR - http://iopscience.iop.org/article/10.1088/1367-2630/18/2/025016 DO - https://doi.org/10.1088/1367-2630/18/2/025016 SN - 1367-2630 VL - 18 SP - 025016 PB - IOP PUBLISHING LTD CY - Bristol, UK AN - OPUS4-35874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Prinz, J. A1 - Heck, Christian A1 - Ellerik, L. A1 - Merk, V. A1 - Bald, Ilko T1 - DNA origami based Au–Ag-core–shell nanoparticle dimers with single-molecule SERS sensitivity N2 - DNA origami nanostructures are a versatile tool to arrange metal nanostructures and other chemical entities with nanometer precision. In this way gold nanoparticle dimers with defined distance can be constructed, which can be exploited as novel substrates for surface enhanced Raman scattering (SERS). We have optimized the size, composition and arrangement of Au/Ag nanoparticles to create intense SERS hot spots, with Raman enhancement up to 10^10, which is sufficient to detect single molecules by Raman scattering. This is demonstrated using single dye molecules (TAMRA and Cy3) placed into the center of the nanoparticle dimers. In conjunction with the DNA origami nanostructures novel SERS substrates are created, which can in the future be applied to the SERS analysis of more complex biomolecular targets, whose position and conformation within the SERS hot spot can be precisely controlled. KW - single molecule spectroscopy KW - DNA origami KW - SERS KW - gold nanoparticles KW - silver nanoparticles PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-358761 UR - http://pubs.rsc.org/en/content/articlelanding/2016/nr/c5nr08674d#!divAbstract DO - https://doi.org/10.1039/C5NR08674D SP - 5612 EP - 5620 PB - Royal Society of Chemistry CY - Cambridge, England AN - OPUS4-35876 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mielke, Johannes A1 - Hanke, F. A1 - Peters, M.V. A1 - Hecht, S. A1 - Persson, M. A1 - Grill, L. T1 - Adatoms underneath single porphyrin molecules on Au(111) N2 - The adsorption of porphyrin derivatives on a Au(111) surface was studied by scanning tunneling microscopy and spectroscopy at low temperatures in combination with density functional theory calculations. Different molecular appearances were found and could be assigned to the presence of single gold adatoms bonded by a coordination bond underneath the molecular monolayer, causing a characteristic change of the electronic structure of the molecules. Moreover, this interpretation could be confirmed by manipulation experiments of individual molecules on and off a single gold atom. This study provides a detailed understanding of the role of metal adatoms in surface–molecule bonding and anchoring and of the appearance of single molecules, and it should prove relevant for the imaging of related molecule–metal systems. PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-324144 UR - http://pubs.acs.org/doi/pdf/10.1021/ja510528x DO - https://doi.org/10.1021/ja510528x SN - 0002-7863 SN - 1520-5126 VL - 137 IS - 5 SP - 1844 EP - 1849 PB - American Chemical Society CY - Washington, DC AN - OPUS4-32414 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wiggenhauser, Herbert A1 - Naus, D.J. T1 - NDE of thick and highly reinforced concrete structures: state of the art N2 - The objective of the report is to present the state-of-the art of non-destructive testing methods and technologies for the inspection of thick, heavily-reinforced structures, (e.g. found in nuclear power plants). Wall thicknesses can be in excess of one meter and the structures often have increased steel reinforcement density. The accessibility for any testing method may be limited due to the presence of liners and other components such as cast-in-place items. Testing methods have to provide solutions for tasks such as locating failure (inclusions, corrosion, voids, delaminations) in the structures or the assessment of the condition of the structure in general. KW - Non-destructuive testing KW - Inspection KW - Nuclear power plant KW - State-of-the-art KW - Highly reinforced concrete KW - NDE KW - Engineering PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-329674 DO - https://doi.org/10.1016/j.proeng.2014.11.055 SN - 1877-7058 VL - 86 SP - 420 EP - 426 PB - Elsevier CY - Amsterdam [u.a.] AN - OPUS4-32967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Köppe, Enrico A1 - Augustin, D. A1 - Bartholmai, Matthias A1 - Daum, Werner T1 - Air-based multi-hop sensor network for the localization of persons N2 - In this work an air-based sensor network for the localization of persons at extensive areas is presented. The developed network consists of a localization device which the person is wearing (BodyGuard-System), a mobile relay station in the air, and a base station. All three parts communicate with the same radio chip. The BodyGuard-System is an inertial navigation system which was developed for localization in difficult environments with high accuracy and low measurement uncertainty. To increase the range of the system, a multi-hop network was built up. The measured data of the BodyGuard-System and the mobile relay station is visualized on a PC in the base station. This multi-hop network is necessary for example for fire department missions. T2 - EuroSensors 2014, 28th European Conference on Solid-State Transducers CY - Brescia, Italy DA - 07.09.2014 KW - WSN KW - Mesh routing KW - Air-based KW - Multi-hop KW - Localization PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-324294 DO - https://doi.org/10.1016/j.proeng.2014.11.540 SN - 1877-7058 VL - 87 SP - 528 EP - 531 PB - Elsevier CY - Amsterdam [u.a.] AN - OPUS4-32429 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cordeiro, F. A1 - Llorente-Mirandes, T. A1 - López-Sánchez, J.F. A1 - Rubio, R. A1 - Sánchez-Agullo, A. A1 - Raber, G. A1 - Scharf, Holger A1 - Vélez, D. A1 - Devesa, V. A1 - Fiamegos, Y. A1 - Emteborg, H. A1 - Seghers, J. A1 - Robouch, P. A1 - De la Calle, M.B. T1 - Determination of total cadmium, lead, arsenic, mercury and inorganic arsenic in mushrooms: outcome of IMEP-116 and IMEP-39 N2 - The Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre (JRC), a Directorate General of the European Commission, operates the International Measurement Evaluation Program (IMEP). IMEP organises inter-laboratory comparisons in support of European Union policies. This paper presents the results of two proficiency tests (PTs): IMEP-116 and IMEP-39, organised for the determination of total Cd, Pb, As, Hg and inorganic As (iAs) in mushrooms. Participation in IMEP-116 was restricted to National Reference Laboratories (NRLs) officially appointed by national authorities in European Union member states. IMEP-39 was open to all other laboratories wishing to participate. Thirty-seven participants from 25 countries reported results in IMEP-116, and 62 laboratories from 36 countries reported for the IMEP-39 study. Both PTs were organised in support to Regulation (EC) No. 1881/2006, which sets the maximum levels for certain contaminants in food. The test item used in both PTs was a blend of mushrooms of the variety shiitake (Lentinula edodes). Five laboratories, with demonstrated measurement capability in the field, provided results to establish the assigned values (Xref). The standard uncertainties associated to the assigned values (uref) were calculated by combining the uncertainty of the characterisation (uchar) with a contribution for homogeneity (ubb) and for stability (ust), whilst uchar was calculated following ISO 13528. Laboratory results were rated with z- and zeta (ζ)-scores in accordance with ISO 13528. The standard deviation for proficiency assessment, σp, ranged from 10% to 20% depending on the analyte. The percentage of satisfactory z-scores ranged from 81% (iAs) to 97% (total Cd) in IMEP-116 and from 64% (iAs) to 84% (total Hg) in IMEP-39. KW - Inorganic arsenic KW - Trace elements KW - Mushrooms KW - Proficiency test PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-326092 DO - https://doi.org/10.1080/19440049.2014.966336 SN - 1944-0057 SN - 1944-0049 VL - 32 IS - 1 SP - 54 EP - 67 PB - Taylor & Francis CY - London [u.a.] AN - OPUS4-32609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kraehnert, R. A1 - Ortel, Erik A1 - Paul, B. A1 - Eckhardt, B. A1 - Kanis, M. A1 - Liu, R. A1 - Antoniou, A. T1 - Electrochemically dealloyed platinum with hierarchical pore structure as highly active catalytic coating N2 - Micro structured reactors are attractive candidates for further process intensification in heterogeneous catalysis. However, they require catalytic coatings with significantly improved space-time yields compared to traditional supported catalysts. We report the facile synthesis of homogeneous nanocrystalline Pt coatings with hierarchical pore structure by electrochemical dealloying of amorphous sputter-deposited platinum silicide layers. Thickness, porosity and surface composition of the catalysts can be controlled by the dealloying procedure. XPS analysis indicates that the catalyst surface is primarily composed of metallic Pt. Catalytic tests in gas-phase hydrogenation of butadiene reveal the typical activity, selectivity and activation energy of nanocrystalline platinum. However, space time yields are about 13 to 200 times higher than values reported for Pt-based catalysts in literature. The highly open metallic pore structure prevents heat and mass transport limitations allowing for very fast reactions and reasonable stability at elevated temperatures. KW - Pt catalysts KW - Pt–Si layers KW - Scanning Electron Microscopy (SEM) KW - Transmission Electron Microscopy (TEM) KW - pore structure KW - electrochemical dealloying PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351393 DO - https://doi.org/10.1039/C4CY00851K SN - 2044-4753 SN - 2044-4761 VL - 5 IS - 1 SP - 206 EP - 216 PB - RSC Publ. CY - Cambridge AN - OPUS4-35139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abbott, A. P. A1 - Abolibda, T. Z. A1 - Davis, S.J. A1 - Emmerling, Franziska A1 - Lourdin, D. A1 - Leroy, E. A1 - Wise, W. R. T1 - Glycol based plasticisers for salt modified starch N2 - Starch is one of the most common and easily obtained natural polymers, making it attractive as a potential bio-based alternative to synthetic polymers. This study shows that a simple quaternary ammonium salt combined with urea or glycols forms effective modifiers that produce flexible plastics with good mechanical properties that are comparable to some polyolefin plastics. The processing conditions are shown to significantly affect the structure of the polymer which has a concomitant effect upon the mechanical and physical properties of the resulting plastic. Using a glycerol based modifier results in a totally sustainable and biodegradable material which can be injection moulded. KW - biodegradable material KW - flexible plastics KW - injection moulded PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351426 DO - https://doi.org/10.1039/C4RA06220E SN - 2046-2069 VL - 4 IS - 76 SP - 40421 EP - 40427 PB - RSC Publishing CY - London AN - OPUS4-35142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hemmann, Felix A1 - Agirrezabal-Telleria, Iker A1 - Jäger, Christian A1 - Kemnitz, E. T1 - Quantification of acidic sites of nanoscopic hydroxylated magnesium fluorides by FTIR and 15N MAS NMR spectroscopy N2 - Lewis and Brønsted sites were quantified in a series of weak acidic hydroxylated magnesium fluorides by Fourier transform infrared spectroscopy (FTIR) and solid state nuclear magnetic resonance spectroscopy (NMR) with pyridine as probe molecule. Molar extinction coefficients, which are necessary for quantitative FTIR measurements, were calculated by an easy approach. It utilizes the fact that both signals, used for the quantification by FTIR, are caused by the same deformation vibration mode of pyridine. Comparison of quantitative FTIR experiments and quantification by NMR shows that concentrations of acidic sites determined by FTIR spectroscopy have to be interpreted with caution. Furthermore, it is shown that the transfer of molar extinction coefficients from one catalyst to another may lead to wrong results. Molar extinction coefficients and concentrations of acidic sites determined by FTIR spectroscopy are affected by grinding and probably the particle size of the sample. High temperature during FTIR experiments has further impact on the quantification results. KW - Acidity KW - Fluoride catalyst KW - Infrared spectroscopy KW - Adsorption of pyridine KW - Molar extinction coefficient determination PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351448 DO - https://doi.org/10.1039/C5RA15116C SN - 2046-2069 VL - 5 IS - 109 SP - 89659 EP - 89668 PB - RSC Publishing CY - London AN - OPUS4-35144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schoknecht, Ute A1 - Mathies, Helena A1 - Wegner, R. T1 - Biocide leaching during field experiments on treated articles N2 - Background: Biocidal products can be sources of active substances in surface waters caused by weathering of treated articles. Marketing and use of biocidal products can be limited according to the European Biocidal Products Regulation if unacceptable risks to the environment are expected. Leaching of active substances from treated articles was observed in field experiments to obtain information on leaching processes and investigate the suitability of a proposed test method. Results: Leaching under weathering conditions proceeds discontinuously and tends to decrease with duration of exposure. It mainly depends on the availability of water, but is also controlled by transport processes within the materials and stability of the observed substances. Runoff amount proved to be a suitable basis to compare results from different experiments. Concentrations of substances are higher in runoff collected from vertical surfaces compared to horizontal ones, whereas the leached amounts per surface area are higher from horizontal surfaces. Gaps in mass balances indicate that additional processes such as degradation and evaporation may be relevant to the fate of active substances in treated articles. Leached amounts of substances were considerably higher when the materials were exposed to intermittent water contact under laboratory conditions as compared to weathering of vertically exposed surfaces. Conclusions: Experiences from the field experiments were used to define parameters of a procedure that is now provided to fulfil requirements of the Biocidal Products Regulation. The experiments confirmed that the amount of water which is in contact with exposed surfaces is the crucial parameter determining leaching of substances. KW - Biozidprodukte KW - Farben KW - Textil KW - Auswaschung KW - Freilandtest KW - Biocidal products KW - Paints KW - Textile KW - Leaching KW - Field test PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-354090 DO - https://doi.org/10.1186/s12302-016-0074-9 VL - 28 IS - 6 SP - 1 EP - 10 PB - Springer CY - SpringerOpen AN - OPUS4-35409 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nguyen, Thi Yen A1 - Rademann, K. A1 - Emmerling, Franziska T1 - Direct evidence of polyamorphism in paracetamol N2 - While polymorphism is a common phenomenon in the crystallization processes of organic compounds, polyamorphism has gained importance only recently. Using sophisticated sample environments and applying in situ scattering methods and vibrational spectroscopy, the complete crystallization process of organic compounds from solution can be traced and characterized. Diffuse scattering from amorphous intermediates can be investigated by analyzing the atomic pair distribution function (PDF) to gain further insights into molecular pre-orientation. The crystallization behavior of paracetamol was studied exemplarily under defined, surface-free conditions. Based on the choice of the solvent, the formation of different polymorphs is promoted. The thermodynamically stable form I and the metastable orthorhombic form II could be isolated in pure form directly from solution. For both polymorphs, the crystallization from solution proceeds via a distinct amorphous precursor phase. PDF analyses of these different amorphous states indicate a specific pre-orientation of the analyte molecules introduced by the solvent. The resulting crystalline polymorph is already imprinted in these proto-crystalline precursors. Direct experimental evidence for the polyamorphism of paracetamol is provided. PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351366 DO - https://doi.org/10.1039/C5CE01583A SN - 1466-8033 VL - 17 IS - 47 SP - 9029 EP - 9036 PB - Royal Society of Chemistry CY - London, UK AN - OPUS4-35136 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hornemann, A. A1 - Eichert, D. A1 - Flemig, Sabine A1 - Ulm, G. A1 - Beckhoff, B. T1 - Qualifying label components for effective biosensing using advanced high-throughput SEIRA methodology N2 - The need for technological progress in bio-diagnostic assays of high complexity requires both fundamental research and constructing efforts on nano-scaled assay recognition elements that can provide unique selectivity and design-enhanced sensitivity features. Nanoparticle induced sensitivity enhancement and its application related to multiplexed capability Surface-Enhanced InfraRed Absorption (SEIRA) assay formats are well suitable for these purposes. The potential of diverse fluorophore–antibody conjugates, being chemisorbed onto low-cost gold nanoparticulate SEIRA substrates, has been explored with respect to their spectral discriminability. These novel biolabels deliver molecular SEIRA fingerprints that have been successfully analyzed by both uni- and multivariate analyzing tools, to discriminate their multiplexing capabilities. We show that this robust spectral encoding via SEIRA fingerprints opens up new opportunities for a fast, reliable and multiplexed high-end screening in biodiagnostics. KW - SEIRA methodology KW - bio-diagnostic KW - nanotechnology PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-351389 DO - https://doi.org/10.1039/C4CP05944A SN - 1463-9076 SN - 1463-9084 VL - 17 IS - 14 SP - 9471 EP - 9479 PB - The Royal Soc. of Chemistry CY - Cambridge AN - OPUS4-35138 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sproesser, G. A1 - Schenker, S. A1 - Pittner, Andreas A1 - Borndörfer, R. A1 - Rethmeier, Michael A1 - Chang, Y.-J. A1 - Finkbeiner, M. T1 - Sustainable welding process selection based on weight space partitions N2 - Selecting a welding process for a given application is crucial with respect to the sustainability of part manufacturing. Unfortunately, since welding processes are evaluated by a number of criteria, preferences for one or the other process can be contradictory. However, the prevalent procedure of weight assignment for each criterion is subjective and does not provide information about the entire solution space. From the perspective of a decision maker it is important to be able to assess the entire set of possible weightings and answer the question which welding process is optimal for which set of weights. This issue is investigated by means of a weight space partitioning approach. Two welding processes are considered with respect to three criteria that reflect their economic and environmental performance. In order to find the most sustainable welding process the underlying weight space partition is evaluated. T2 - 13th Global Conference on Sustainable Manufacturing – Decoupling Growth from Resource Use CY - Bình Dương New City, Vietnam DA - 16.09.2015 KW - Welding costs KW - Multi-criteria decision support KW - LCA KW - Welding process selection KW - GMAW KW - Multi-attribute decision method PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-353740 DO - https://doi.org/10.1016/j.procir.2016.01.077 SN - 2212-8271 VL - 40 SP - 127 EP - 132 PB - Elsevier B.V. AN - OPUS4-35374 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Carl, Peter A1 - Schneider, Rudolf T1 - Optimization and evaluation of a hapten microarray using chemometric methods N2 - The demands for the assessment of water quality are increasing steadily, making it necessary to routinely monitor multiple contaminants in water samples. For this application a hapten microarray was developed. In order to reach the required low detection limits a design of experiments (DoE) approach was used to optimize the assay performance. Here we show that a Box-Behnken design plan is an adequate choice for the straightforward exploration of hapten microarray assay parameters. For both read-out systems studied (fluorophore-labelled detection antibodies or enzymatic signal development followed by reflectometric scan, respectively), it was possible to significantly extend the measurement ranges. Furthermore, it could be shown that multivariate data analysis, here partial least squares regression (PLS), can improve the prediction accuracy of 'unknown' samples when used as calibration model, compared to classical, univariate data evaluation methods. KW - Koffein KW - Caffeine KW - Proteine microarray KW - Design of experiments KW - Multivariate data analysis KW - Partial least squares regression KW - Small molecule detection KW - Microarray KW - Immunoarray KW - Immunoassay KW - ELISA KW - Chemometrie KW - Chemometrics PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-344672 DO - https://doi.org/10.1016/j.proeng.2015.08.684 SN - 1877-7058 VL - 120 SP - 501 EP - 506 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-34467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lempke, L. A1 - Fischer, Tobias A1 - Bell, Jérémy A1 - Kraus, Werner A1 - Rurack, Knut A1 - Krause, N. T1 - Gold-catalyzed allene cycloisomerization for pyrrole synthesis: towards highly fluorinated BODIPY dyes N2 - A novel synthetic strategy toward highly fluorinated BODIPY dyes with exceptional photostabilities relying on sustainable gold catalysis has been developed. A key to the tailored pyrrole precursors is the gold catalysis performed in ionic liquids as the reaction medium, allowing a facile recycling of the catalysts. The dyes prepared are well-matching with the spectral windows of popular rhodamine dyes and possess high brightness while showing a distinctly higher photostability than the rhodamines especially in aprotic solvents. KW - Gold-Katalyse KW - BODIPY-Farbstoffe KW - Photostabilität KW - Fluor-Substitution KW - Fluoreszenz PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-344692 DO - https://doi.org/10.1039/c4ob02671c SN - 1477-0520 SN - 1477-0539 VL - 13 IS - 12 SP - 3787 EP - 3791 PB - RSC CY - Cambridge AN - OPUS4-34469 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pelkner, Matthias A1 - Pohl, Rainer A1 - Erthner, Thomas A1 - Stegemann, Robert A1 - Kreutzbruck, Marc A1 - Sergeeva-Chollet, N. T1 - Eddy current testing with high-spatial resolution probes using MR arrays as receiver N2 - Magneto-resistive (MR) sensor arrays are suited for high resolution eddy current testing (ET) of aerospace components due to two significant advantages compared to conventional coil systems. First, to obtain high spatial resolution they can be manufactured down to the µm-regime without losing their outstanding field sensitivity. Secondly, MR technology has a relatively frequency-independent sensitivity in the range of common ET-frequencies thus providing a benefit for low frequency applications. This paper presents measurements using MR array probes consisting of 32 TMR-elements (tunnel magneto resistance), an ASIC, and subsequent readout components. A source for generating the eddy currents inside the material under test is also implemented onboard of the PCB. These probes were developed in the IMAGIC-project* for detection and imaging of surface breaking defects. The performance of the new sensor system has been investigated for several mock-ups, Aluminum and Titanium plate specimens having small adjacent boreholes with diameter of 0.44 mm and micro notches in the µm-range, respectively. To compare our results we used conventional eddy current probes. The MR sensor elements have a length of around 60 µm leading to a nearly 'point like' measurement. Neighbouring boreholes (depth 0.25 mm) with a separation of 0.6 mm between their centres could be resolved with a good SNR, and more important, the boreholes could be confidently distinguished using the TMR-probes. In case of conventional probes a reliable separation was not possible. In this paper we present the MR-ET-probes of the IMAGIC consortium and a comparison with conventional techniques. *The IMAGIC-project ('Integrated Magnetic imagery based on spIntronics Components', 2011 – 2014, project reference: 288381) was funded by the European Commission, Seventh Framework Programme. Further partners involved in the consortium beside BAM and CEA were INESC-ID and INESC-MN (Portugal), Sensitec GmbH (Germany), Tecnatom S.A. (Spain), and Airbus Group (France). T2 - 7th International symposium on NDT in aerospace CY - Bremen, Germany DA - 16.11.2015 KW - TMR KW - GMR KW - Sensor array KW - Eddy current testing (ET) KW - Aerospace PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-344254 SN - 978-3-940283-76-4 N1 - Serientitel: DGZfP-Proceedings – Series title: DGZfP-Proceedings IS - DGZfP-BB 156 SP - We.5.A.4, 1 EP - 8 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung e.v. (DGZfP) AN - OPUS4-34425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zheng, H. A1 - Kappatos, V. A1 - Niederleithinger, Ernst A1 - Ertel, Jens-Peter A1 - Grohmann, Maria A1 - Selcuk, C. A1 - Gan, T.-H. T1 - Defect detection in concrete pile using impulse response measurements with sine sweep excitations N2 - For pile integrity inspection, a low cost and portable shaker was used to create the sine sweep signal for pile excitation. The impulse response function, calculated by the deconvolution of pile response from the sine sweep excitation, was proposed to identify the echoes in the piles due to the pile’s impedance changes. The proposed methodology has been evaluated and validated both numerically and experimentally. Based on the results from the simulations and experiments, it was found that the impulse response measurement with sine sweep excitation could be an effective tool to detect the echoes of the pile toe and the defects in the pile. T2 - NDT-CE 2015 - International symposium non-destructive testing in civil engineering CY - Berlin, Germany DA - 15.09.2015 KW - Impulse response function KW - Sine sweep excitation KW - Pile integrity KW - Damage detection PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-347157 SN - 1435-4934 SP - 1 EP - 4 PB - Technische Universität Berlin / Bundesanstalt für Materialforschung und -prüfung AN - OPUS4-34715 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gaal, Mate A1 - Dohse, Elmar A1 - Bartusch, Jürgen A1 - Kreutzbruck, Marc T1 - Luftultraschallprüfung von CFK mit planaren und fokussierenden Wandlern N2 - Für die Prüfung von Leichtbaustrukturen ist in den letzten Jahren ein vermehrter Einsatz der Luftultraschallprüfung zu verzeichnen. Insbesondere eignet sich Luftultraschall für die Prüfung von Faserkunststoffverbunden und hybrider Werkstoffverbunde, die ihre Anwendung in der Automobilindustrie und Luftfahrt finden. Für den Bau von marktüblichen Luftultraschall-Wandlern werden Piezokomposite mit Anpassschichten versehen. Ihre Herstellung ist allerdings sehr anspruchsvoll und die erreichbaren Signal-Rausch-Abstände sind für viele Prüfprobleme als noch nicht ausreichend einzustufen. Zwecks gesteigerter Effizienz beim Schallübertrag in die Luft wurden Luftultraschall-Sender und -Empfänger aus zellulärem Polypropylen entwickelt. Dieses piezoelektrische Material ist aufgrund seiner geringer Dichte und seiner sehr geringen Schallgeschwindigkeit an die niedrige akustische Impedanz der Luft deutlich besser angepasst, als die üblicherweise verwendeten Anpassschichten. Letztere können bei Polypropylen-Wandlern daher gänzlich vermieden werden. In diesem Beitrag wird Luftultraschall-Prüfung an zwei verschiedenen CFK-Testkörpern vorgestellt: an einer Platte mit T-Stringern aus dem Seitenleitwerk eines Flugzeugs und an einer Platte mit künstlich eingebrachten Fehlern. Es wurde mit unterschiedlichen planaren und fokussierenden Wandlern geprüft. Marktübliche Wandler mit Anpassschichten wurden mit den selbstentwickelten Wandlern aus zellulärem Polypropylen verglichen. Der Signal-Rausch-Abstand und die laterale Auflösung wurden sowohl im Prüfaufbau mit senkrechter Einschallung als auch mit Schrägeinschallung gemessen. Die Ergebnisse zeigen, dass die Schrägeinschallung zwar den Signal-Rauschabstand erhöht, aber die laterale Auflösung verschlechtern kann. T2 - DACH Jahrestagung 2015 CY - Salzburg, Austria DA - 11.05.2015 PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-349751 UR - http://jt2015.dgzfp.de/Portals/jt2015/BB/mi1a3.pdf SP - Mi.1.A.3-1 EP - Mi.1.A.3-9 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-34975 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jeromenok, J. A1 - Böhlmann, W. A1 - Jäger, Christian A1 - Weber, J. T1 - Carbon dioxide adsorption in Betulin-based micro- and macroporous polyurethanes N2 - Separation of CO2. Microporous polyurethane networks were prepared based on a renewable resource. Betulin, extracted from birch bark, is used as a structure-directing diol monomer in A3-B2 monomers. The resulting microporous networks show very promising CO2/N2 selectivities. The state of adsorbed CO2 is analyzed by in situ NMR spectroscopy, and pure physisorption is proven. The preparation of monolithic materials is demonstrated as well. KW - Carbon dioxide KW - Gas adsorption KW - Microporous polymers KW - Renewable resources KW - Solid state NMR spectroscopy PY - 2013 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-304431 DO - https://doi.org/10.1002/open.201200045 SN - 2191-1363 VL - 2 IS - 1 SP - 17 EP - 20 PB - Wiley-VCH-Verl. CY - Weinheim AN - OPUS4-30443 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gebhardt, M.O. A1 - Gumenyuk, Andrey A1 - Rethmeier, Michael T1 - Numerical analysis of hot cracking in laser-hybrid welded tubes N2 - In welding experiments conducted on heavy wall pipes, the penetration mode (full or partial penetration) occurred to be a significant factor influencing appearance of solidification cracks. To explain the observed phenomena and support further optimization of manufacturing processes, a computational model was developed, which used a sophisticated strategy to model the material. High stresses emerged in the models in regions which showed cracking during experiments. In partial penetration welding, they were caused by the prevention of weld shrinkage due to the cold and strong material below the joint. Another identified factor having an influence on high stress localization is bulging of the weld. PY - 2013 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-302961 DO - https://doi.org/10.1155/2013/520786 SN - 1687-8442 SN - 1687-8434 IS - Article ID 520786 SP - 1 EP - 8 PB - Hindawi Publishing Corporation CY - New York, NY, USA AN - OPUS4-30296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hodoroaba, Vasile-Dan A1 - Akcakayiran, D. A1 - Grigoriev, D.O. A1 - Shchukin, D.G. T1 - Characterization of micro- and nanocapsules for self-heating anti-corrosion coatings by high-resolution SEM with coupled transmission mode and EDX N2 - The observation of morphological details down to the nanometer range of the outer surface of micro-, submicro- and nanoparticles in a high-resolution scanning electron microscope (SEM) was extended with in-depth observation by enabling the transmission mode in the SEM, i.e. TSEM. The micro- and nanocapsules characterized in this study were fabricated as depots for protective agents to be embedded in innovative self-healing coatings. By combining the two imaging modes (upper and in-depth observation) complementing each other a better characterisation by a more comprehensive interpretation of the 'consistency' of the challenging specimens, e.g. including details 'hidden' beyond the surface or the real specimen shape at all, has been attained. Furthermore, the preparation of the quasi electron transparent samples onto thin supporting foils enables also elemental imaging by energy dispersive X-ray spectroscopy (EDX) with high spatial resolution. Valuable information on the elemental distribution in individual micro-, submicro- and even nanocapsules completes the '3D' high resolution morphological characterization at the same multimodal SEM/TSEM/EDX system. KW - Scanning electron microscopy (SEM) KW - High-resolution transmission in SEM (TSEM) KW - Energy dispersive X-ray spectroscopy (EDX) KW - Micro- and nanocapsules KW - Anti-corrosion coatings PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-304201 DO - https://doi.org/10.1039/c3an01717f SN - 0003-2654 SN - 1364-5528 VL - 139 IS - 8 SP - 2004 EP - 2010 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-30420 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kruschwitz, Sabine T1 - Feuchtemessung im Bauwesen - Ein Überblick N2 - Ein Großteil der Schäden im Baubereich ist auf feuchteinduzierte Prozesse zurückzuführen. Der Erhaltungsaufwand allein im Hochbau wurde bereits vor einiger Zeit auf jährlich ca. 35 Mrd. Euro geschätzt. Aus diesem Grund hat die Feuchtemessung in der Bauwerksdiagnose eine sehr hohe Bedeutung - und im Idealfall sollte sie natürlich alles können: schnell sein, wiederholbar und zerstörungsfrei anwendbar. Zwar gibt es eine Vielzahl an verfügbaren Feuchtemesstechniken, oft fällt es Anwendern aber schwer, einzuschätzen welches die richtige Prüfmethode für ihr Problem ist. Genormt sind nur direkte und zerstörende Verfahren, die zwar teils hochgenau, aber doch nur stichprobenartig Aussagen liefern können. Die anderen, zerstörungsfreien Methoden basieren auf der Änderung feuchteabhängiger physikalischer Materialeigenschaften. Ihre Grundlagen, sowie Vor- und Nachteile werden hier näher dargestellt. T2 - Fachtagung Bauwerksdiagnose 2014 CY - Berlin, Germany DA - 13.02.2014 KW - Feuchtemessung KW - Zerstörungsfreie Prüfung KW - Baustoffe PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-311672 UR - http://www.bauwerksdiagnose2014.de/portals/bwd2014/BB/vortrag%205.pdf UR - http://www.bauwerksdiagnose2014.de/Berichtsband SN - 978-3-940283-56-6 SP - 1 EP - 8 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-31167 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Madia, Mauro A1 - Zerbst, Uwe A1 - Beier, H.T. T1 - A model for the determination of the fatigue life in technical alloys containing large and small defects N2 - The determination of the fatigue life in technical alloys containing large and small defects must rely on a propagation model which accounts for short and long crack growth. Recently an analytical model which incorporates propagation in the short crack regime and plastic correction for the crack driving force has been presented by two of the authors. This work is intended to show further validation of the model, taking into account data sets for different materials with different testing conditions. Despite the assumptions about missing parameters, the value of which had to be taken from the literature, the predictions showed a fairly good approximation of the fatigue lives. A possible interpretation of the results in terms of multiple crack initiation and propagation at higher loads is proposed. T2 - EFC20 - 20th European conference on fracture CY - Trondheim, Norway DA - 30.06.2014 KW - Fatigue strength KW - Crack propagation KW - Short cracks PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-311961 DO - https://doi.org/10.1016/j.mspro.2014.06.082 SN - 2211-8128 VL - 3 SP - 493 EP - 498 PB - Curran CY - Red Hook, NY, USA AN - OPUS4-31196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Doriti, A. A1 - Brosnan, S. A1 - Weidner, Steffen A1 - Schlaad, H. T1 - Synthesis of polysarcosine from air and moisture stable N-phenoxycarbonyl-N-methylglycine assisted by tertiary amine base N2 - Polysarcosine (M-n = 3650-20 000 g mol(-1), D similar to 1.1) was synthesized from the air and moisture stable N-phenoxycarbonyl-N-methylglycine. Polymerization was achieved by in situ transformation of the urethane precursor into the corresponding N-methylglycine-N-carboxyanhydride, when in the presence of a non-nucleophilic tertiary amine base and a primary amine initiator. KW - Polysarcosine KW - MALDI-TOF MS KW - Synthesis PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-359309 DO - https://doi.org/10.1039/c6py00221h SN - 1759-9954 SN - 1759-9962 VL - 7 IS - 18 SP - 3067 EP - 3070 AN - OPUS4-35930 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neamtu, M. A1 - Nadejde, C. A1 - Brinza, L. A1 - Dragos, O. A1 - Gherghel, D. A1 - Paul, Andrea T1 - Iron phthalocyanine-sensitized magnetic catalysts for BPA photodegradation N2 - The catalytic behavior of iron phthalocyanine (FePc)-sensitized magnetic nanocatalysts was evaluated for their application in the oxidative treatment of Bisphenol A (BPA) under mild environmental conditions. Two types of FePc (Fe(II)Pc and Fe(III)Pc), which are highly photosensitive compounds, were immobilized on the surface of functionalized magnetite. The nanomaterials were characterized by high resolution transmission electron microscopy (HR-TEM), X-ray difraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analyses (TGA). The generation of singlet Oxygen by nanomaterials was also investigated. In the presence of UVA light exposure (365nm) and 15mM H2O2, the M@Fe(III)Pc photocatalyst gave the best results; for a catalyst concentration of 2.0gL −1, around 60% BPA was removed after 120min of reaction. These experimental conditions were further tested under natural solar light exposure, for which also M@Fe(III)Pc exhibited enhanced oxidative catalytic activity, being able to remove 83% of BPA in solution. The water samples were less cytotoxic after treatment, this being confrmed by the MCF-7 cell viability assay. KW - Photosensitization KW - magnetic nanocatalysts KW - BPA removal PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506368 DO - https://doi.org/10.1038/s41598-020-61980-6 VL - 10 IS - 1 SP - 5376 AN - OPUS4-50636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen A1 - Scheliga, F. T1 - Synthesis of cyclic polymers and flaws of the Jacobson–Stockmayer theory N2 - Cyclic poly(L-lactide)s were prepared by ring-opening polymerization combined with simultaneous polycondensation (ROPPOC) in bulk at 160 ° with dibutyltin bis(4-cyanophenoxide) as catalyst. It is demonstrated by MALDI TOF mass spectrometry and 1H NMR end group analyses that cycles are formed by endto-end cyclization in addition to “back-biting” transesterification. Formation of high molar mass cyclic poly L-lactide)s by means of several more reactive ROPPOC catalysts presented previously and in new experiments is discussed. These experimental results, together with theoretical arguments, prove that part of the Jacobson–Stockmayer theory is wrong. The critical monomer concentration, above which end-toend cyclization is seemingly impossible, does not exist and reversible like irreversible polycondensations can theoretically proceed up to 100% conversion, so that finally all reaction products will necessarily adopt a cyclic architecture. KW - Polylactide KW - MALDI-TOF MS KW - Cyclization PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506419 DO - https://doi.org/10.1039/d0py00226g VL - 11 IS - 14 SP - 2595 EP - 2604 PB - Royal Society for Chemistry AN - OPUS4-50641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weidner, Steffen A1 - Meyer, A. A1 - Kricheldorf, H. R. T1 - Ring–Ring Equilibration in Solid, Even-Numbered Cyclic Poly(l-lactide)s and their Stereocomplexes N2 - Even-numbered cyclic poly(d-lactide) and poly(l-lactide) are prepared by ringexpansion polymerization. The cyclic pol(l-lactide) is annealed either at 120 or at 160 °C for several days. The progress of transesterification in the solid state is monitored by the formation of odd-numbered cycles via matrix-assisted laser desorption/ionization-time of flight mass spectrometry. The changes of the crystallinity are monitored by differential scanning calorimetry, wideand small-angle x-ray scattering (WAXS and SAXS) measurements. Despite total even-odd equilibration at 160 °C, the crystallinity of poly(l-lactide) is not reduced. Furthermore, the crystallinity of the stereocomplexes of both cyclic polylactides do not decrease or vanish, as expected, when a blocky or random stereosequence is formed by transesterification. This conclusion is confirmed by 13C NMR spectroscopy. These measurements demonstrate that transesterification is a ring–ring equilibration involving the loops on the surfaces of the lamellar crystallites thereby improving crystallinity and 3D packing of crystallites without significant broadening of the molecular weight distribution. KW - Polylactide KW - MALDI-TOF MS KW - Cyclization PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506458 DO - https://doi.org/10.1002/macp.202000012 VL - 221 IS - 9 SP - 2000012 PB - Wiley-VCH Verlag AN - OPUS4-50645 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Evsevleev, Sergei A1 - Sevostianov, I. A1 - Mishurova, Tatiana A1 - Hofmann, M. A1 - Garcés, G. A1 - Bruno, Giovanni T1 - Explaining Deviatoric Residual Stresses in Aluminum Matrix Composites with Complex Microstructure N2 - The residual stresses in multiphase metal Matrix composites with both random planar-oriented short fibers and particles were studied by neutron diffraction and by a model based on the reformulation of classic Maxwell’s homogenization method. Contrary to common understanding and state-of-the-art models, we experimentally observed that randomly oriented phases possess non-hydrostatic residual stress. The recently developed modeling Approach allows calculating the residual stress in all phases of the composites. It rationalizes the presence of deviatoric stresses Accounting for the interaction of random oriented phases with fibers having preferential orientation. KW - Metal matrix composite KW - Residual stress KW - Deviatoric KW - Micromechanics PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506472 DO - https://doi.org/10.1007/s11661-020-05697-1 VL - 51 IS - 6 SP - 3104 EP - 3113 PB - Springer AN - OPUS4-50647 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Jungnickel, Robert A1 - Dariz, P. T1 - Insights into the CaSO4–H2O System: A Raman-Spectroscopic Study N2 - Even though being the subject of natural scientific research for many decades, the system CaSO4–H2O, consisting of the five crystalline phases gypsum, bassanite, and the anhydrites III, II, and I, has left many open questions for research. Raman spectroscopy was used because of its structural sensitivity and in situ measurement capability to obtain further insight by studying phase transitions in both ex situ and in situ experiments. The findings include significant contributions to the completeness and understanding of Raman spectroscopic data of the system. The dehydration path gypsum–bassanite–anhydrite III was shown to have strong parallels to a physical drying process, which depends on many parameters beyond the burning temperature. Raman band width determination was demonstrated to enable the quantitative discrimination of α-bassanite and β-bassanite as well as the postulated three sub-forms of anhydrite II (AII), which are all based on differences in crystallinity. In the latter case, the observed continuous structural variations over increasing burning temperatures were elucidated as a combination of decreasing surface areas and healing of crystal lattice defects. We propose an only two-fold sub-division of AII into reactive “disordered AII” and much less reactive “crystalline AII” with a transition temperature of 650°C ± 50 K. KW - Gypsum KW - Bassanite KW - Hemihydrate KW - Anhydrite KW - Raman spectroscopy PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506701 DO - https://doi.org/10.3390/min10020115 SN - 2075-163X VL - 10 IS - 2 SP - 115, 35 PB - MDPI CY - Basel AN - OPUS4-50670 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishurova, Tatiana A1 - Artzt, K. A1 - Haubrich, J. A1 - Evsevleev, Sergei A1 - Evans, Alexander A1 - Meixner, M. A1 - Serrano Munoz, Itziar A1 - Sevostianov, I. A1 - Requena, G. A1 - Bruno, Giovanni T1 - Connecting Diffraction-Based Strain with Macroscopic Stresses in Laser Powder Bed Fused Ti-6Al-4V N2 - The laser powder bed fusion (LPBF) production process often results in large residual stress (RS) in the parts. Nondestructive techniques to determine RS are badly needed. However, a reliable quantification of macro-RS (i.e., stress at the component level) by means of diffraction-based techniques is still a great challenge, because the link between diffraction-based strain and macro-RS is not trivial. In this study, we experimentally determine (by means of in-situ synchrotron radiation diffraction) this link for LPBF Ti-6Al-4V. We compare our results with commonly used models to determine the so-called diffraction elastic constants (DECs). We show that LPBF materials possess different DECs than wrought alloys, simply because their microstructural and mechanical properties are different. We also show that the existing models can be used to calculate DECs only if high accuracy of the RS values is not required. If the peculiarities of the microstructure have to be taken into account (as is the case of additively manufactured materials), a radically new approach is desirable. KW - Tiatanium KW - Synchrotron X-ray diffraction KW - Macroscopic stress KW - Laser powder bed fusion KW - Texture KW - Diffraction elastic constants PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506483 DO - https://doi.org/10.1007/s11661-020-05711-6 VL - 51 IS - 6 SP - 3194 EP - 3204 PB - Springer AN - OPUS4-50648 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pfretzschner, Beate A1 - Schaupp, Thomas A1 - Hannemann, Andreas A1 - Schultz, Michael A1 - Griesche, Axel T1 - On the Genesis of Artifacts in Neutron Transmission Imaging of Hydrogenous Steel Specimens N2 - Hydrogen-charged supermartensitic steel samples were used to systematically investigate imaging artifacts in neutron radiography. Cadmium stencils were placed around the samples to shield the scintillator from excessive neutron radiation and to investigate the influence of the backlight effect. The contribution of scattered neutrons to the total detected intensity was investigated by additionally varying the sample-detector distance and applying a functional correlation between distance and intensity. Furthermore, the influence of the surface roughness on the edge effect due to refraction was investigated. KW - Refraction KW - Neutron imaging KW - Hydrogen KW - Supermartensitic steel KW - Backlight KW - Scattering PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506587 DO - https://doi.org/10.3390/jimaging6040022 VL - 6 IS - 22 SP - 1 EP - 10 PB - MDPI CY - Basel, Switzerland AN - OPUS4-50658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kromm, Arne A1 - Lausch, Thomas A1 - Schröpfer, Dirk A1 - Rhode, Michael A1 - Kannengießer, Thomas T1 - Influence of welding stresses on relief cracking during heat treatment of a creep-resistant 13CrMoV steel: Part I - Effect of heat control on welding stresses and stress relief cracking N2 - The avoidance of failures during the fabrication or operation of petrochemical reactors made of creep-resistant, low-alloy steels as 13CrMoV9-10 requires still research despite over 60 years of international investigations in the field of stress relief cracking. The quality of modern base materials and filler metals leads to the fact that previously known crack causes, such as impurities of S or P, recede into the background. Rather, the causes are increasingly to be found in the fabrication process. Investigations on the influence of heat control on the stresses in welded components and thus on the stress relief cracking sensitivity under realistic manufacturing conditions are not yet available. This work is subdivided in two parts. Part 1 of this study focused on the effect of heat control during submerged arc welding on the stresses. For this purpose, a testing facility was applied, which allows to observe the forces and moments accumulating during welding or heat treatment in a component-like specimen under shrinkage restraint. The stress acting in the specimen increases with higher preheat/interpass temperatures and higher heat input. During the heat treatment, the stresses are relieved. Nevertheless, cracks are formed already during heating. The total crack length correlates with the heat input. KW - Welding KW - Creep-resistant steel KW - Post weld heat treatment KW - Stress relief cracking PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506271 DO - https://doi.org/10.1007/s40194-020-00875-6 SN - 1878-6669 VL - 64 IS - 5 SP - 807 EP - 817 PB - Springer CY - Berlin AN - OPUS4-50627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kromm, Arne A1 - Lausch, Thomas A1 - Schröpfer, Dirk A1 - Rhode, Michael A1 - Kannengießer, Thomas T1 - Influence of welding stresses on relief cracking during heat treatment of a creep-resistant 13CrMoV steel: Part II - Mechanisms of stress relief cracking during post weld heat treatment N2 - Welding of 13CrMoV9-10 vanadium steel requires care due to an increased susceptibility to stress relief cracking during post weld heat treatment. Previous research into the crack formation in creep-resistant steels has focused on thermal and metallurgical factors; however, little knowledge has been gathered regarding the crack formation during post weld heat treatment considering real-life restraint conditions. This work is subdivided in two parts. Part I showed that an increasing heat input during submerged arc welding under restraint led to an increasing stress level in the joint prior to the post weld heat treatment. The magnitude of stress relief cracking observed in the heat-affected zone after the post weld heat treatment is affected by the heat input. In Part II of this work, the cracks and the associated microstructure which occurred under restraint were studied. The application of a Special acoustic emission analysis indicated that the cracks formed in a temperature range between 300 and 500 °C during the post weld heat treatment. The toughness in the heat-affected zone of the restrained welds was affected by the welding heat input. Microstructural analyses of all specimens revealed accelerated aging due to precipitation of carbides during post weld heat treatment under restraint. KW - Welding KW - Creep-resistant steel KW - Post weld heat treatment KW - Stress relief cracking PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-506283 DO - https://doi.org/10.1007/s40194-020-00881-8 SN - 1878-6669 VL - 64 SP - 819 EP - 829 PB - Springer CY - Berlin AN - OPUS4-50628 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adamczyk, Burkart A1 - Neuhold, S. A1 - Drissen, P. A1 - Algermissen, D. A1 - Presoly, P. A1 - Sedlazeck, K. P. A1 - Schenk, J. A1 - Raith, J. G. A1 - Pomberger, R. A1 - Vollprecht, D. T1 - Tailoring the FeO/SiO2 ratio in electric arc furnace slags to minimize the leaching of Vanadium and Chromium N2 - Based on recently published research on leaching control mechanisms in electric arc furnace (EAF) slags, it is assumed that a FeO/SiO2 ratio of around one leads to low leached V and Cr concentrations. This ratio influences the mineral phase composition of the slag toward higher amounts of spinel and a lower solubility of calcium silicate phases by suppressing the formation of magnesiowuestite and highly soluble calcium silicate phases. To evaluate this hypothesis, laboratory and scaled up tests in an EAF pilot plant were performed on slag samples characterized by elevated V and Cr leaching and a high FeO/SiO2 ratio. Prior to the melting experiments, the optimum FeO/SiO2 ratio was calculated via FactSageTM. In the melting experiments, the ratio was adjusted by adding quartz sand, which also decreased the basicity (CaO/SiO2) of the slag. As a reference, remelting experiments without quartz sand addition were conducted and additionally, the influence of the cooling rate of the slag was examined. The remelted (without quartz sand) and the remelted modified slags (with quartz sand) were analyzed chemically and mineralogically and the leaching behavior was investigated. The modification of the slags yielded a minimized release of V and Cr, supporting the hypothesis that the FeO/SiO2 ratio influences the mineralogy and the leaching behavior. KW - Electric arc furnace slags KW - FactSage calculations KW - EAF slags KW - Leaching control mechanisms KW - Melting experiments PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507748 DO - https://doi.org/10.3390/app10072549 VL - 10 IS - 7 SP - 2549 EP - 2565 AN - OPUS4-50774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen A1 - Meyer, A. T1 - High Tm poly(L-lactide)s via REP or ROPPOC of L-lactide N2 - A new kind of high melting (HTm) pol(L-lactide) was discovered when cyclic poly(L-lactide)s were prepared by ring-expansion polymerization with cyclic tin catalysts at 130–160 °C in bulk. By DSC measurements with 10 K min−1 melting temperatures (Tm) in the range of 190–196 °C were found. The WAXS and SAXS measurements evidenced that not a new crystal lattice but a well-ordered morphology and a higher perfection of the crystallites are responsible for the high Tm values and high crystallinities. Under identical reaction conditions SnOct2-catalyzed and alcohol-initiated ROPs do not yield these crystallites. Furthermore, it was found that the standard crystallites are kinetically favored upon rapid crystallization, whereas the high melting form of poly(L-lactide) is thermodynamically more stable. KW - Polylactide KW - MALDI-TOF MS KW - ROPPOC PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507477 DO - https://doi.org/10.1039/c9py01908a VL - 11 IS - 12 SP - 2182 EP - 2193 PB - Royal Society of Chemistry AN - OPUS4-50747 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tjaden, B. A1 - Lisec, Jan A1 - Schramm, A. T1 - N-Myc-induced metabolic rewiring creates novel therapeutic vulnerabilities in neuroblastoma N2 - N-Myc is a transcription factor that is aberrantly expressed in many tumor types and is often correlated with poor patient prognosis. Recently, several lines of evidence pointed to the fact that oncogenic activation of Myc family proteins is concomitant with reprogramming of tumor cells to cope with an enhanced need for metabolites during cell growth. These adaptions are driven by the ability of Myc proteins to act as transcriptional amplifiers in a tissue-of-origin specific manner. Here, we describe the effects of N-Myc overexpression on metabolic reprogramming in neuroblastoma cells. Ectopic expression of N-Myc induced a glycolytic switch that was concomitant with enhanced sensitivity towards 2-deoxyglucose, an inhibitor of glycolysis. Moreover, global metabolic profiling revealed extensive alterations in the cellular metabolome resulting from overexpression of N-Myc. Limited supply with either of the two main carbon sources, glucose or glutamine, resulted in distinct shifts in steady-state metabolite levels and significant changes in glutathione metabolism. Interestingly, interference with glutamine-glutamate conversion preferentially blocked proliferation of N-Myc overexpressing cells, when glutamine levels were reduced. Thus, our study uncovered N-Myc induction and nutrient levels as important metabolic master switches in neuroblastoma cells and identified critical nodes that restrict tumor cell proliferation. KW - Mass-Spectrometry KW - Cancer KW - MYCN PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507193 DO - https://doi.org/10.1038/s41598-020-64040-1 VL - 10 IS - 1 SP - 7157 AN - OPUS4-50719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vandrich, Jasmina A1 - Pfeiffer, F. A1 - Alfaro Espinoza, Gabriela A1 - Kunte, Hans-Jörg T1 - Contribution of mechanosensitive channels to osmoadaptation and ectoine excretion in Halomonas elongata N2 - For osmoadaptation the halophilic bacterium Halomonas elongata synthesizes as its main compatible solute the aspartate derivative ectoine. H. elongata does not rely entirely on synthesis but can accumulate ectoine by uptake from the surrounding environment with the help of the osmoregulated transporter TeaABC. Disruption of the TeaABC-mediated ectoine uptake creates a strain that is constantly losing ectoine to the medium. However, the efflux mechanism of ectoine in H. elongata is not yet understood. H. elongata possesses four genes encoding mechanosensitive channels all of which belong to the small conductance type (MscS). Analysis by qRT-PCR revealed a reduction in transcription of the mscS genes with increasing salinity. The response of H. elongata to hypo- and hyperosmotic shock never resulted in up-regulation but rather in downregulation of mscS transcription. Deletion of all four mscS genes created a mutant that was unable to cope with hypoosmotic shock. However, the knockout mutant grew significantly faster than the wildtype at high salinity of 2 M NaCl, and most importantly, still exported 80% of the ectoine compared to the wildtype. We thus conclude that a yet unknown system, which is independent of mechanosensitive channels, is the major export route for ectoine in H. elongata. KW - Halomonas elongata KW - Ectoine KW - Osmotic shock KW - Solute excretion KW - Osmoadaptation KW - Mechanosensitive channel KW - MscS PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507229 DO - https://doi.org/10.1007/s00792-020-01168-y VL - 24 SP - 421 EP - 432 PB - Springer AN - OPUS4-50722 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schlick-Hasper, Eva A1 - Neitsch, Marcel A1 - Goedecke, Thomas T1 - Industrial leak testing of dangerous goods packagings N2 - The Dangerous Goods Regulations currently do not include limit leakage rates orsensitivity requirements for industrial leak testing procedures that are equivalent tothe bubble test, which is the prescribed test method for design type testing ofdangerous goods packagings. During series production of such packagings, variousmethods are used, which often do not meet the requirements of the bubble test withregard to important criteria.Sensitivity, flow direction, pressure level and automatability are particularly importantfactors when selecting a suitable industrial leak testing method.The following methods are in principle both suitable and equally effective as thebubble test: pressure rise test (vacuum chamber), ultrasonic bubble leak detectionand gas detection methods (pressure technique by accumulation and vacuumchamber technique).To ensure a uniform test level during design type testing and production line leaktesting and therefore a comparable safety level as required by the Dangerous GoodsRegulations, it is necessary to include a more precise specification in these regula-tions. This requires, on the one hand, information about the sensitivity of the bubbletest and, on the other hand, the inclusion of a list of suitable, equally effective indus-trial test methods with their specific boundary conditions. T2 - 22nd IAPRI World Packaging CY - Online meeting KW - Bubble test KW - Dangerous goods packagings KW - Industrial leak testing KW - Leakproofness test KW - Series production PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507521 DO - https://doi.org/10.1002/pts.2502 SP - 1 EP - 14 PB - Wiley AN - OPUS4-50752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heilmann, Maria A1 - Kulla, Hannes A1 - Prinz, Carsten A1 - Bienert, Ralf A1 - Reinholz, Uwe A1 - de Oliveira Guilherme Buzanich, Ana A1 - Emmerling, Franziska T1 - Advances in Nickel Nanoparticle Synthesis via Oleylamine Route N2 - Nickel nanoparticles are an active research area due to their multiple applications as catalysts in different processes. A variety of preparation techniques have been reported for the synthesis of these nanoparticles, including solvothermal, microwave-assisted, and emulsion techniques. The well-studied solvothermal oleylamine synthesis route comes with the drawback of needing standard air-free techniques and often space-consuming glassware. Here, we present a facile and straightforward synthesis method for size-controlled highly monodisperse nickel nanoparticles avoiding the use of, e.g., Schlenk techniques and space-consuming labware. The nanoparticles produced by this novel synthetic route were investigated using small-angle X-ray scattering, transmission electron microscopy, X-ray diffraction, and X-ray spectroscopy. The nanoparticles were in a size range of 4–16 nm, show high sphericity, no oxidation, and no agglomeration after synthesis. KW - Nanoparticle synthesis KW - Nickel nanoparticles KW - SAXS KW - TEM KW - XAS PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507531 DO - https://doi.org/10.3390/nano10040713 VL - 10 IS - 4 SP - 713 PB - MDPI AN - OPUS4-50753 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schaumann, P. A1 - Schürmann, K. A1 - Pittner, Andreas A1 - Rethmeier, Michael T1 - Automatically Welded Tubular X Joints for Jacket Substructures – Prediction of the Technical Fatigue Crack Location N2 - To increase the competitiveness of jacket substructures compared to monopiles a changeover from an individual towards a serial jacket production based on automated manufactured tubular joints combined with standardized pipes has to be achieved. Therefore, this paper addresses fatigue tests of automatically welded tubular X-joints focusing on the location of the technical fatigue crack. The detected location of the technical crack is compared to numerical investigations predicting the most fatigue prone notch considering the structural stress approach as well as the notch stress approach. Besides, the welding process of the automated manufactured tubular X-joints is presented. T2 - Nordic Steel 2019 CY - Copenhagen, Denmark DA - 18.09.2019 KW - Automated arc welding KW - Fatigue tests KW - Tubular X-joints KW - Technical crack detection KW - Local fatigue approaches PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518490 DO - https://doi.org/10.1002/cepa.1140 VL - 3 IS - 3-4 SP - 823 EP - 828 PB - Wiley-VCH Verlag GmbH on behalf of Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG CY - Berlin AN - OPUS4-51849 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schaumann, P. A1 - Schürmann, K. A1 - Pittner, Andreas A1 - Rethmeier, Michael T1 - Experimental investigations on the fatigue resistance of automatically welded tubular X-joints for jacket support structures N2 - The development within the offshore wind sector towards more powerful turbines combined with increasing water depth for new wind parks is challenging both the designer as well as the manufacturer of bottom fixed support structures. Besides XL-monopiles, the market developed an innovative and economic jacket support structure which is based on automatically manufactured tubular joints combined with standardized pipes. Besides the improvements for a serial manufacturing process the automatically welded tubular joints show a great potential in terms of fatigue resistance e.g. due to a smooth weld geometry without sharp notches. However, these benefits are not considered yet within the fatigue design process of automatically manufactured jacket substructures according to current standards due to the lack of suitable S-N curves. Therefore, 32 axial fatigue tests on single and double-sided automatically welded tubular X-joints have been performed to determine a new hot spot stress related S-N curve. Based on these constant amplitude fatigue tests a new S-N curve equal to a FAT 126 curve was computed which implicitly includes the benefits of the automatically welding procedure. T2 - EERA Deep Wind 2020 CY - Trondheim, Norway DA - 15.01.2020 KW - Notch stress approach KW - Fatigue tests KW - Automated manufacturing KW - Tubular X-joints KW - Structural stress approach PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518509 DO - https://doi.org/10.1088/1742-6596/1669/1/012022 VL - 1669 SP - 012022 PB - IOP Publishing Ltd AN - OPUS4-51850 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigt, Oliver A1 - Knabe, Nicole A1 - Nitsche, Sarah A1 - Erdmann, Eileen A1 - Schumacher, Julia A1 - Gorbushina, Anna T1 - An advanced genetic toolkit for exploring the biology of the rock‑inhabiting black fungus Knufia petricola N2 - Microcolonial black fungi are a group of ascomycetes that exhibit high stress tolerance, yeast-like growth and constitutive melanin formation. They dominate a range of hostile natural and man-made environments, from desert rocks and salterns to dishwashers, roofs and solar panels. Due to their slow growth and a lack of genetic tools, the underlying mechanisms of black fungi’s phenotypic traits have remained largely unexplored. We chose to address this gap by genetically engineering the rock-inhabiting fungus Knufia petricola (Eurotiomycetes, Chaetothyriales), a species that exhibits all characteristics of black fungi. A cell biological approach was taken by generating K. petricola strains expressing green or red fluorescent protein variants. By applying: (1) traditional gene replacement; (2) gene editing and replacement via plasmid-based or ribonucleoprotein (RNP)-based CRISPR/Cas9, and (3) silencing by RNA interference (RNAi), we constructed mutants in the pathways leading to melanin, carotenoids, uracil and adenine. Stable single and double mutants were generated with homologous recombination (HR) rates up to 100%. Efficient, partially cloning-free strategies to mutate multiple genes with or without resistance cassettes were developed. This state-of-the-art genetic toolkit, together with the annotated genome sequence of strain A95, firmly established K. petricola as a model for exploring microcolonial black fungi. KW - Subaerial biofilms KW - Biodeterioration KW - Fluorescent microscopy KW - CRISPR/Cas9 KW - RNA interference PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518601 DO - https://doi.org/10.1038/s41598-020-79120-5 VL - 10 IS - 1 SP - 22021 PB - Springer Nature AN - OPUS4-51860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liehr, Sascha A1 - Münzenberger, Sven A1 - Borchardt, Christopher T1 - Long-distance fiber optic vibration sensing using convolutional neural networks as real-time denoisers N2 - A long distance range over tens of kilometers is a prerequisite for a wide range of distributed fiber optic vibration sensing applications. We significantly extend the attenuation-limited distance range by making use of the multidimensionality of distributed Rayleigh backscatter data: Using the wavelength-scanning coherent optical time domain reflectometry (WS-COTDR) technique, backscatter data is measured along the distance and optical frequency dimensions. In this work, we develop, train, and test deep convolutional neural networks (CNNs) for fast denoising of these two-dimensional backscattering results. The very compact and efficient CNN denoiser “DnOTDR” outperforms state-of-the-art image denoising algorithms for this task and enables denoising data rates of 1.2 GB/s in real time. We demonstrate that, using the CNN denoiser, the quantitative strain measurement with nm/m resolution can be conducted with up to 100 km distance without the use of backscatter-enhanced fibers or distributed Raman or Brillouin amplification. KW - Neural networks KW - Fiber optic KW - Vibration sensing PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518694 DO - https://doi.org/10.1364/OE.402789 VL - 28 IS - 26 SP - 39325 AN - OPUS4-51869 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -