TY - CONF A1 - Saathoff, F. A1 - Cantré, S. A1 - Müller, Werner ED - Ziegler, M. ED - Bräu, G. ED - Heerten, G. ED - Laackmann, K. T1 - Modified filtration criteria for non-woven geotextiles in landfill construction N2 - The German landfill ordinance includes a certification requirement for geosynthetics used in landfill liner and capping systems. The certification guidelines describe the basis for the design of geosynthetics used in landfill construction. According to the rules which are usually applied, the thickness of the filter geotextile has to be at least 30 times the characteristic opening size O90. Filter geotextiles which are often used in geocomposite drains have a mass per area of 200 g/m² and do not fulfill this requirement. In this paper modified filter criteria for geosynthetics are presented with a particular focus on These geotextile filters in geocomposite drains. T2 - 10th International conference on geosynthetics CY - Berlin, Germany DA - 21.09.2014 KW - Filtration criteria KW - Drainage KW - Geotextile KW - Non-woven KW - Landfill KW - Certification guidelines PY - 2014 SN - 978-3-9813953-9-6 SP - 1 EP - 7 AN - OPUS4-31578 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meyerhofer, F. A1 - Dissinger, F. A1 - Weigert, Florian A1 - Jungclaus, J. A1 - Müller-Caspary, K. A1 - Waldvogel, S. R. A1 - Resch-Genger, Ute A1 - Voss, T. T1 - Citric Acid Based Carbon Dots with Amine Type Stabilizers: pHSpecific N2 - We report the synthesis and spectroscopic characteristics of two different sets of carbon dots (CDs) formed by hydrothermal reaction between citric acid and polyethylenimine (PEI) or 2,3-diaminopyridine (DAP). Although the formation of amide-based species and the presence of citrazinic acid type derivates assumed to be responsible for a blue emission is confirmed for both CDs by elemental analysis, infrared spectroscopy, and mass spectrometry, a higher abundance of sp2-hybridized nitrogen is observed for DAP-based CDs, which causes a red-shift of the n-π* absorption band relative to the one of PEI-based CDs. These CD Systems possess high photoluminescence quantum yields (QY) of ∼40% and ∼48% at neutral pH, demonstrating a possible tuning of the optical properties by the amine precursor. pH-Dependent spectroscopic studies revealed a drop in QY to < 9% (pH ∼ 1) and < 21% (pH ∼ 12) for both types of CDs under acidic and basic conditions. In contrast, significant differences in the pHdependency of the n-π* transitions are found for both CD types which are ascribed to different (de)protonation sequences of the CD-specific fluorophores and functional groups using Zeta potential analysis. KW - Fluorescence KW - Particle KW - Nano KW - Surface group analysis KW - Carbon dot KW - C-dot KW - Fluorescent probe KW - Quantum yield KW - Synthesis KW - IR KW - MS KW - Polymer KW - Ligand PY - 2020 DO - https://doi.org/10.1021/acs.jpcc.9b11732 VL - 124 IS - 16 SP - 8894 EP - 8904 PB - American Chemical Society AN - OPUS4-50813 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rack, A. A1 - Zabler, S. A1 - Riesemeier, Heinrich A1 - Weidemann, Gerd A1 - Müller, Bernd R. A1 - Helfen, L. A1 - Stiller, M. A1 - Knabe, C. A1 - Goebbels, Jürgen A1 - Banhart, J. T1 - Nondestructive 3D insights into foamy metals and bioregenerative ceramics KW - X-ray Computed Tomography KW - Metal foams KW - Bioregenerative ceramics PY - 2008 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/infos/bessy/highlights2007.pdf#page=34 SN - 1611-6127 SP - 34 EP - 35 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-17538 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rack, A. A1 - Riesemeier, Heinrich A1 - Zabler, S. A1 - Weitkamp, T. A1 - Müller, Bernd R. A1 - Weidemann, Gerd A1 - Modregger, P. A1 - Banhart, J. A1 - Helfen, L. A1 - Danilewsky, A.N. A1 - Gräber, H.G. A1 - Heldele, R. A1 - Mayzel, B. A1 - Goebbels, Jürgen A1 - Baumbach, T. ED - Stuart R. Stock, T1 - The high-resolution synchrotron-based imaging stations at the BAMline (BESSY) and TopoTomo (ANKA) N2 - The BAMline at the BESSY light source in Berlin and the TopoTomo beamline at the ANKA synchrotron facility in Karlsruhe (both Germany) operate in the hard X-ray regime (above 6 keV) with similiar photon flux density. For typical imaging applications, a double multilayer monochromator or a filtered white beam is used. In order to optimise the field of view and the resolution of the available indirect pixel detectors, different optical systems have been installed, adapted, respectively, to a large field of view (macroscope) and to high spatial resolution (microscope). They can be combined with different camera systems, ranging from 16-bit dynamic range slow-scan CCDs to fast CMOS cameras. The spatial resolution can be brought substantially beyond the micrometer limit by using a Bragg magnifier. The moderate flux of both beamlines compared to other 3rd generation light sources is compensated by a dedicated scintillator concept. For selected applications, X-ray beam collimation has proven to be a reliable approach to increase the available photon flux density. Absorption contrast, phase contrast, holotomography and refraction-enhanced imaging are used depending on the application. Additionally, at the TopoTomo beamline digital white beam synchrotron topography is performed, using the digital X-ray pixel detectors installed. KW - Microtomography KW - Non-destructive evaluation KW - Coherent imaging KW - X-ray refraction KW - X-ray phase contrast KW - Synchrotron-CT KW - Synchrotron instrumentation KW - Scintillator KW - Bragg magnification KW - Holotomography KW - X-ray topography PY - 2008 DO - https://doi.org/10.1117/12.793721 SN - 0277-786X VL - 7078 SP - 70780X-1 - 70780X-9 AN - OPUS4-18296 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hakim, I. A1 - Laquai, René A1 - Schumacher, David A1 - Müller, Bernd R. A1 - Graja, P. A1 - Meyendorf, N. A1 - Donaldson, S. T1 - The Effect of Manufacturing Conditions on Discontinuity Population and Fatigue Fracture Behavior in Carbon/Epoxy Composites N2 - Carbon fiber composites have been increasingly used in aerospace, military, sports, automotive and other fields due to their excellent properties, including high specific strength, high specific modulus, corrosion resistance, fatigue resistance, and low thermal expansion coefficient. Interlaminar fracture is a serious failure mode leading to a loss in composite stiffness and strength. Iscontinuities formed during manufacturing process degrade the fatigue life and interlaminar fracture resistance of the composite. In his study, three approaches were implemented and their results were correlated to quantify discontinuities effecting static and fatigue interlaminar fracture behavior of carbon fiber composites. Samples were fabricated by hand layup vacuum bagging manufacturing process under three different vacuum levels, indicated High (-686 mmHg), Moderate (-330 mmHg) and Poor (0 mmHg). Discontinuity content was quantified throughthickness by destructive and nondestructive techniques. Eight different NDE methods were conducted including imaging NDE methods: X-Ray laminography, ultrasonic, high frequency eddy current, pulse thermography, pulse phase thermography and lock-in-thermography, and averaging NDE techniques: X-Ray refraction and thermal conductivity measurements. Samples were subsequently destructively serial sectioned through-thickness into several layers. Both static and fatigue interlaminar fracture behavior under Mode I were conducted. The results of several imaging NDE methods revealed the trend in percentages of discontinuity. However, the results of averaging NDE methods showed a clear correlation since they gave specific values of discontinuity through-thickness. Serial sectioning exposed the composite’s internal structure and provided a very clear idea about the type, shape, size, distribution and location of most discontinuities included. The results of mechanical testing showed that discontinuities lead to a decrease in Mode I static interlaminar fracture toughness and a decrease in Mode I cyclic strain energy release rates fatigue life. Finally, all approaches were correlated: the resulted NDE percentages and parameters were correlated with the features revealed by the destructive test of serial sectioning and static and fatigue values in order to quantify discontinuities such as delamination and voids. T2 - QNDE 2016 CY - Atlanta, GA, USA DA - 17.07.2016 KW - Carbon Fber Reinforced Polymers KW - Nondestructive Testing KW - X-ray Imaging KW - Ultrasound KW - Thermography PY - 2017 SN - 978-0-7354-1474-7 DO - https://doi.org/10.1063/1.4974661 SN - 0094-243X N1 - Geburtsname von Schumacher, David: Walter, D. - Birth name of Schumacher, David: Walter, D. VL - 1806 SP - UNSP 090017, 1 EP - 11 PB - AIP Publishing CY - Melville, NY, USA AN - OPUS4-39716 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ast, S. A1 - Fischer, Tobias A1 - Müller, H. A1 - Mickler, W. A1 - Schwichtenberg, M. A1 - Rurack, Knut A1 - Holdt, H.-J. T1 - Integration of the 1,2,3-triazole 'click' motif as a potent signalling element in metal ion responsive fluorescent probes N2 - In a systematic approach we synthesized a new series of fluorescent probes incorporating donor–acceptor (D-A) substituted 1,2,3-triazoles as conjugative π-linkers between the alkali metal ion receptor N-phenylaza-[18]crown-6 and different fluorophoric groups with different electron-acceptor properties (4-naphthalimide, meso-phenyl-BODIPY and 9-anthracene) and investigated their performance in organic and aqueous environments (physiological conditions). In the charge-transfer (CT) type probes 1, 2 and 7, the fluorescence is almost completely quenched by intramolecular CT (ICT) processes involving charge-separated states. In the presence of Na+ and K+ ICT is interrupted, which resulted in a lighting-up of the fluorescence in acetonitrile. Among the investigated fluoroionophores, compound 7, which contains a 9-anthracenyl moiety as the electron-accepting fluorophore, is the only probe which retains light-up features in water and works as a highly K+/Na+-selective probe under simulated physiological conditions. Virtually decoupled BODIPY-based 6 and photoinduced electron transfer (PET) type probes 3–5, where the 10-substituted anthracen-9-yl fluorophores are connected to the 1,2,3-triazole through a methylene spacer, show strong ion-induced fluorescence enhancement in acetonitrile, but not under physiological conditions. Electrochemical studies and theoretical calculations were used to assess and support the underlying mechanisms for the new ICT and PET 1,2,3-triazole fluoroionophores. KW - Charge transfer KW - Click chemistry KW - Electron transfer KW - Fluorescent probes KW - Metal ions PY - 2013 DO - https://doi.org/10.1002/chem.201201575 SN - 0947-6539 SN - 1521-3765 VL - 19 IS - 9 SP - 2990 EP - 3005 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-27742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rack, A. A1 - Zabler, S. A1 - Müller, Bernd R. A1 - Riesemeier, Heinrich A1 - Weidemann, Gerd A1 - Lange, Axel A1 - Goebbels, Jürgen A1 - Hentschel, Manfred P. A1 - Görner, Wolf T1 - High resolution synchrotron-based radiography and tomography using hard X-rays at the BAMline (BESSY II) N2 - The use of high brilliance and partial coherent synchrotron light for radiography and computed tomography (CT) allows to image micro-structured, multi-component specimens with different contrast modes and resolutions up to submicrometer range. This is of high interest for materials research, life science and non-destructive evaluation applications. An imaging setup for microtomography and radiography installed at BESSY II (a third generation synchrotron light source located in Berlin, Germany) as part of its first hard X-ray beamline (BAMline) can now be used for absorption, refraction as well as phase contrast — dedicated to inhouse research and applications by external users. Monochromatic synchrotron light between 6 keV and 80 keV is attained via a fully automated double multilayer monochromator. For imaging applications the synchrotron beam transmitted by the sample is converted with a scintillator into visible light. By use of microscope optics this luminescence image is then projected onto, e.g., a CCD chip. Several scintillating materials are used in order to optimise the performance of the detector system. Different optical systems are available for imaging ranging from a larger field of view and moderate resolutions (macroscope — up to 14 mm x 14 mm field of view) to high resolution (microscope — down to 0.35 μm pixel size), offering magnifications from 1.8× to 40×. Additionally asymmetric cut Bragg crystals in front of the scintillator can be used for a further magnification in one dimension by a factor of about 20. Slow and fast cameras are available, with up to 16 bit dynamic range. We show the suitability of the setup for numerous applications from materials research and life science. KW - Microtomography KW - Non-destructive evaluation KW - Synchrotron instrumentation KW - Coherent imaging KW - X-ray refraction KW - Phase contrast KW - Holotomography KW - Synchrotron-CT KW - Scintillator KW - Bragg magnification PY - 2008 DO - https://doi.org/10.1016/j.nima.2007.11.020 SN - 0168-9002 SN - 0167-5087 VL - 586 IS - 2 SP - 327 EP - 344 PB - North-Holland CY - Amsterdam AN - OPUS4-17738 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mühler, T. A1 - Helsch, G. A1 - Heinrich, J.G. A1 - Yao, Dongxu A1 - Gräf, S. A1 - Müller, F.A. A1 - Günster, Jens T1 - Strategies for the selective volume sintering of ceramics N2 - The present study is dealing with the basic physics for a novel way to generate a free-formed ceramic body, not like common layer by layer, but directly by Selective Volume Sintering (SVS) in a compact block of ceramic powder. To penetrate with laser light into the volume of a ceramic powder compact it is necessary to investigate the light scattering properties of ceramic powders. Compared with polymers and metals, ceramic materials are unique as they offer a wide optical window of transparency. The optical window typically ranges from below 0.3 up to 5 µm wave length. In the present study thin layers of quartz glass (SiO2) particles have been prepared. As a function of layer thickness and the particle size, transmission and reflection spectra in a wave length range between 0.5 and 2.5 µm have been recorded. Depending on the respective particle size and by choosing a proper relation between particle size and wave length of the incident laser radiation, it is found that light can penetrate a powder compact up to a depth of a few millimeters. With an adjustment of the light absorption properties of the compact the initiation of sintering in the volume of the compact is possible. KW - Additive Manufacturing PY - 2014 DO - https://doi.org/10.1557/jmr.2014.174 SN - 0884-2914 VL - 29 IS - 17 SP - 2095 EP - 2099 PB - Materials Research Society CY - Warrendale, Pa. AN - OPUS4-32544 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rahner, E. A1 - Thiele, T. A1 - Voss, Heike A1 - Müller, F.A. A1 - Bonse, Jörn A1 - Gräf, S. T1 - Objective, high-throughput regularity quantification of laser-induced periodic surface structures (LIPSS) N2 - The growing demand for precise surface functionalization through laser-generated periodic surface structures highlights the necessity for efficient, reproducible, and objective evaluation methods to evaluate their structural regularity. We introduce ReguΛarity (v.1.2.7), a freely available, Python-based software with a graphical user interface for the automated, quantitative assessment of the regularity of laser-induced periodic surfaces structures (LIPSS), obtained from optical microscopy, SEM, or AFM. The software integrates image segmentation, one- and two-dimensional Fourier analyses, and gradient-based orientation determination to facilitate a comprehensive regularity analysis of grating-like (quasi-)periodic surface patterns with spatial periods Λ. This is achieved through the proposed regularity tuple R, composed of five key parameters: the normalized spread of the spatial period RΛ,2D (from 2D-FT), the normalized variation of the most frequent spatial period RΛ (from 1D-FT), the Gini coefficient G, the Dispersion of the LIPSS Orientation Angle δθ (DLOA), and the mean phase deviation . To demonstrate its applicability, we compare ideal sinusoidal patterns with SEM images obtained from LIPSS on stainless steel (AISI 316L) and aluminum alloy (AlMg5) surfaces, confirming the software’s ability to objectively distinguish between varying levels of structural regularity. ReguΛarity facilitates high-throughput analysis and data-driven process optimization in surface engineering and laser materials processing. KW - Laser-induced periodic surface structures (LIPSS) KW - Image processing KW - Regularity quantification KW - Fourier analysis KW - Structural homogeneity PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-654070 DO - https://doi.org/10.1016/j.apsusc.2026.165919 SN - 0169-4332 VL - 726 SP - 1 EP - 12 PB - Elsevier B.V. AN - OPUS4-65407 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, S. T1 - Langzeitlagerung von Klärschlammaschen ab 2029? Erste Erfahrungen zur Phosphorrückgewinnung aus deponierten Klärschlammverbrennungsaschen N2 - Das Institut für Siedlungswasserwirtschaft (ISA) der RWTH Aachen University sowie die Bundesanstalt für Materialforschung und -prüfung (BAM) untersuchen gemeinsam fünf deponierte KSA, die von drei Deponiebetreibern ausgebaut und zur Verfügung gestellt wurden sind. Im Fokus der Untersuchungen stehen die physikalische und chemische Charakterisierung der deponierten KSA sowie deren P-Rückgewinnungspotenzial bei der Behandlung in thermochemischen sowie nasschemischen Verfahren. Diese Ergebnisse werden im Vergleich mit „frischen“, also nicht deponierten KSA-Proben vergleichbarer Herkunft bewertet, um so den Einfluss der Lagerung auf die KSA zu erfassen. T2 - Berliner Klärschlamm Konferenz CY - Berlin, Germany DA - 11.11.2025 KW - Phosphor KW - Langzeitlagerung KW - Deponie KW - Rückgewinnung KW - Klärschlammasche PY - 2025 AN - OPUS4-64832 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, S. A1 - Herzel, Hannes A1 - Adam, Christian A1 - Montag, D. ED - Holm, O. ED - Thomé-Kozmiensky, E. ED - Quicker, P. ED - Kopp-Assenmacher, S. T1 - Langzeitlagerung von Klärschlammaschen ab 2029? Erste Erfahrungen zur Phosphorrückgewinnung aus deponierten Klärschlammverbrennungsaschen N2 - Das Institut für Siedlungswasserwirtschaft (ISA) der RWTH Aachen University sowie die Bundesanstalt für Materialforschung und -prüfung (BAM) untersuchen gemeinsam fünf deponierte KSA, die von drei Deponiebetreibern ausgebaut und zur Verfügung gestellt wurden sind. Im Fokus der Untersuchungen stehen die physikalische und chemische Charakterisierung der deponierten KSA sowie deren P-Rückgewinnungspotenzial bei der Behandlung in thermochemischen sowie nasschemischen Verfahren. Diese Ergebnisse werden im Vergleich mit „frischen“, also nicht deponierten KSA-Proben vergleichbarer Herkunft bewertet, um so den Einfluss der Lagerung auf die KSA zu erfassen. T2 - Berliner Klärschlamm Konferenz CY - Berlin, Germany DA - 11.11.2025 KW - Klärschlammasche KW - Recycling KW - Deponie KW - Monoverbrennung PY - 2025 SN - 978-3-911006-63-7 VL - 8 SP - 192 EP - 202 PB - Thomé-Kozmiensky Verlag GmbH CY - Neuruppin AN - OPUS4-65017 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lackmann, C. A1 - Velki, M. A1 - Šimić, A. A1 - Müller, Axel A1 - Braun, U. A1 - Ečimović, S. A1 - Hollert, H. T1 - Two types of microplastics (polystyrene-HBCD and car tire abrasion) affect oxidative stress-related biomarkers in earthworm Eisenia andrei in a time-dependent manner N2 - Microplastics are small plastic fragments that are widely distributed in marine and terrestrial environments. While the soil ecosystem represents a large reservoir for plastic, research so far has focused mainly on the impact on aquatic ecosystems and there is a lack of information on the potentially adverse effects of microplastics on soil biota. Earthworms are key organisms of the soil ecosystem and are due to their crucial role in soil quality and fertility a suitable and popular model organism in soil ecotoxicology. Therefore, the aim of this study was to gain insight into the effects of environmentally relevant concentrations of microplastics on the earthworm Eisenia andrei on multiple levels of biological organization after different exposure periods. Earthworms were exposed to two types of microplastics: (1) polystyrene-HBCD and (2) car tire abrasion in natural soil for 2, 7, 14 and 28 d. Acute and chronic toxicity and all subcellular investigations were conducted for all exposure times, avoidance behavior assessed after 48 h and reproduction after 28 d. Subcellular endpoints included enzymatic biomarker responses, namely, carboxylesterase, glutathione peroxidase, acetylcholinesterase, glutathione reductase, glutathione S-transferase and catalase activities, as well as fluorescence-based measurements of oxidative stress-related markers and multixenobiotic resistance activity. Multiple biomarkers showed significant changes in activity, but a recovery of most enzymatic activities could be observed after 28 d. Overall, only minor effects could be observed on a subcellular level, showing that in this exposure scenario with environmentally relevant concentrations based on German pollution levels the threat to soil biota is minimal. However, in areas with higher concentrations of microplastics in the environment, these results can be interpreted as an early warning signal for more adverse effects. In conclusion, these findings provide new insights regarding the ecotoxicological effects of environmentally relevant concentrations of microplastics on soil organisms. KW - Microplastics KW - Earthworms KW - Toxicity KW - Biomarker KW - oxidative stress PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545423 DO - https://doi.org/10.1016/j.envint.2022.107190 VL - 163 SP - 1 EP - 12 PB - Elsevier Ltd. AN - OPUS4-54542 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liens, A. A1 - Reveron, H. A1 - Douillard, T. A1 - Blanchard, N. A1 - Lughi, V. A1 - Sergo, V. A1 - Laquai, René A1 - Müller, Bernd R. A1 - Bruno, Giovanni A1 - Schomer, S. A1 - Fürderer, T. A1 - Adolfsson, E. A1 - Courtois, N. A1 - Swain, M. A1 - Chevalier, J. T1 - Phase transformation induces plasticity with negligible damage in ceria-stabilized zirconia-based ceramics N2 - Ceramics and their composites are in general brittle materials because they are predominantly made up of ionic and covalent bonds that avoid dislocation motion at room temperature. However, a remarkable ductile behavior has been observed on newly developed 11 mol.% ceria-stabilized zirconia (11Ce-TZP) composite containing fine alumina (8 vol.% Al2O3) and elongated strontium hexa-aluminate (8 vol.% SrAl12O19) grains. The as-synthesized composite also has shown full resistance to Low Temperature Degradation (LTD), relatively high strength and exceptionally high Weibull modulus, allowing its use in a broader range of biomedical applications. In this study, to deepen the understanding of plastic deformation in Ce-TZP based composites that could soon be used for manufacturing dental implants, different mechanical tests were applied on the material, followed by complete microstructural characterization. Distinct from pure Ce-TZP material or other zirconia-based ceramics developed in the past, the material here studied can be permanently strained without affecting the Young modulus, indicating that the ductile response of tested samples cannot be associated to damage occurrence. This ductility is related to the stress-induced tetragonal to monoclinic (t-m) zirconia phase transformation, analogue to Transformation-Induced Plasticity (TRIP) steels, where retained austenite is transformed to martensite. The aim of this study is to corroborate if the observed plasticity can be associated exclusively to the zirconia t-m phase transformation, or also to microcraking induced by the transformation. The t-m transformed-zones produced after bending and biaxial tests were examined by X-ray refraction and SEM/TEM coupled with Raman. The results revealed that the observed elastic-plastic behavior occurs without extensive microcracking, confirming a purely elastic-plastic behavior driven by the phase transformation (absence of damage). KW - Zirconia KW - Ceria KW - Ceramic matrix composite KW - Plasticity KW - Phase transformation KW - X-Ray Refraction PY - 2020 UR - http://www.sciencedirect.com/science/article/pii/S1359645419307177 DO - https://doi.org/10.1016/j.actamat.2019.10.046 SN - 1359-6454 VL - 183 SP - 261 EP - 273 PB - Elsevier Ltd. AN - OPUS4-49740 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mielke, Johannes A1 - Dohányosová, P. A1 - Müller, P. A1 - López-Vidal, S. A1 - Hodoroaba, Vasile-Dan T1 - Evaluation of electrospray as a sample preparation tool for electron microscopic investigations: Toward quantitative evaluation of nanoparticles N2 - The potential of electrospray deposition, for the controlled preparation of particles for imaging in electron microscopes, is evaluated on various materials: from mono-modal suspensions of spherical particles to multimodal suspensions and to real-world industrial materials. It is shown that agglomeration is reduced substantially on the sample carrier, compared with conventional sample preparation techniques. For the first time, it is possible to assess the number concentration of a tri-modal polystyrene suspension by electron microscopy, due to the high Deposition efficiency of the electrospray. We discovered that some suspension stabilizing surfactants form artifact particles during electrospraying. These can be avoided by optimizing the sprayed suspension. KW - Electrospary KW - Nanoparticles KW - Sample preparation KW - TEM grid KW - SEM PY - 2017 DO - https://doi.org/10.1017/S1431927616012587 SN - 1431-9276 SN - 1435-8115 VL - 23 IS - 1 SP - 163 EP - 172 PB - Cambridge University Press AN - OPUS4-39244 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Cant, D. J. H. A1 - Minelli, C. A1 - Sparnacci, K. A1 - Müller, Anja A1 - Kalbe, H. A1 - Stoger-Pollach, M. A1 - Unger, Wolfgang A1 - Werner, W. S. M. A1 - Shard, A. G. T1 - Surface-Energy Control and Characterization of Nanoparticle Coatings N2 - Accurate and reproducible measurement of the structure and properties of high-value nanoparticles is extremely important for their commercialization. A significant proportion of engineered nanoparticle systems consist of some form of nominally core-shell structure, whether by design or unintentionally. Often, these do not form an ideal core-shell structure, with typical deviations including polydispersity of the core or shell, uneven or incomplete shells, noncentral cores, and others. Such systems may be created with or without intent, and in either case an understanding of the conditions for formation of such particles is desirable. Precise determination of the structure, composition, size, and shell thickness of such particles can prove challenging without the use of a suitable range of characterization techniques. Here, the authors present two such polymer core-shell nanoparticle systems, consisting of polytetrafluoroethylene cores coated with a range of thicknesses of either polymethylmethacrylate or polystyrene. By consideration of surface energy, it is shown that these particles are expected to possess distinctly differing coating structures, with the polystyrene coating being incomplete. A comprehensive characterization of these systems is demonstrated, using a selection of complementary techniques including scanning electron microscopy, scanning transmission electron microscopy, thermogravimetric analysis, dynamic light scattering, differential centrifugal sedimentation, and X-ray photoelectron spectroscopy. By combining the results provided by these techniques, it is possible to achieve superior characterization and understanding of the particle structure than could be obtained by considering results separately. KW - Nanoparticles KW - Core-shell KW - XPS KW - Size KW - Thickness KW - Damage PY - 2020 DO - https://doi.org/10.1021/acs.jpcc.0c02161 VL - 124 IS - 20 SP - 11200 EP - 11211 PB - ACS CY - Washington DC AN - OPUS4-50899 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Anja A1 - Sparnacci, K. A1 - Unger, Wolfgang A1 - Tougaard, S. T1 - Determining nonuniformities of core-shell nanoparticle coatings by analysis of the inelastic background of X-ray photoelectron spectroscopy survey spectra N2 - Most real core-shell nanoparticle (CSNP) samples deviate from an ideal core-shell structure potentially having significant impact on the particle properties. An ideal structure displays a spherical core fully encapsulated by a shell of homogeneous thickness, and all particles in the sample exhibit the same shell thickness. Therefore, analytical techniques are required that can identify and characterize such deviations. This study demonstrates that by analysis of the inelastic background in X-ray photoelectron spectroscopy (XPS) survey spectra, the following types of deviations can be identified and quantified: the nonuniformity of the shell thickness within a nanoparticle sample and the incomplete encapsulation of the cores by the shell material. Furthermore, CSNP shell thicknesses and relative coverages can be obtained. These results allow for a quick and straightforward comparison between several batches of a specific CSNP, different coating approaches, and so forth. The presented XPS methodology requires a submonolayer distribution of CSNPs on a substrate. Poly(tetrafluoroethylene)-poly(methyl methacrylate) and poly(tetrafluoroethylene)-polystyrene polymer CSNPs serve as model systems to demonstrate the applicability of the approach. KW - Core-shell KW - Nanoparticles KW - Inelastic background KW - Polymers KW - QUASES KW - XPS PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511315 DO - https://doi.org/10.1002/sia.6865 SN - 0142-2421 SN - 1096-9918 VL - 52 SP - 1 EP - 8 PB - Wiley CY - Chichester AN - OPUS4-51131 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brüngel, R. A1 - Rückert, J. A1 - Müller, P. A1 - Babick, F. A1 - Friedrich, C. M. A1 - Ghanem, A. A1 - Hodoroaba, Vasile-Dan A1 - Mech, A. A1 - Weigel, S. A1 - Wohlleben, W. A1 - Rauscher, H. T1 - NanoDefiner Framework and e-Tool Revisited According to the European Commission’s Nanomaterial Definition 2022/C 229/01 N2 - The new recommended definition of a nanomaterial, 2022/C 229/01, adopted by the European Commission in 2022, will have a considerable impact on European Union legislation addressing chemicals, and therefore tools to implement this new definition are urgently needed. The updated NanoDefiner framework and its e-tool implementation presented here are such instruments, which help stakeholders to find out in a straightforward way whether a material is a nanomaterial or not. They are two major outcomes of the NanoDefine project, which is explicitly referred to in the new definition. This work revisits the framework and e-tool, and elaborates necessary adjustments to make these outcomes applicable for the updated recommendation. A broad set of case studies on representative materials confirms the validity of these adjustments. To further foster the sustainability and applicability of the framework and e-tool, measures for the FAIRification of expert knowledge within the e-tool’s knowledge base are elaborated as well. The updated framework and e-tool are now ready to be used in line with the updated recommendation. The presented approach may serve as an example for reviewing existing guidance and tools developed for the previous definition 2011/696/EU, particularly those adopting NanoDefine project outcomes. KW - Nanomaterial definition KW - Nanomaterial categorisation KW - Nanomaterial regulation KW - Nanomaterial legislation KW - Decision support KW - FAIRification PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571618 DO - https://doi.org/10.3390/nano13060990 SN - 2079-4991 VL - 13 IS - 6 - Special Issue "Identification and Quantification of Nanomaterials" SP - 1 EP - 16 PB - MDPI CY - Basel, CH AN - OPUS4-57161 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Baer, D. R. A1 - Cant, D. J. H. A1 - Castner, D. G. A1 - Ceccone, G. A1 - Engelhard, M. H. A1 - Karakoti, A. S. A1 - Müller, Anja ED - Hodoroaba, Vasile-Dan ED - Unger, Wolfgang ED - Shard, A. G. T1 - Preparation of nanoparticles for surface analysis N2 - A variety of methods used to prepare nano-objects for surface analysis are described along with information about when they might be best applied. Intrinsic properties of NPs which complicate their characterization and need to be considered when planning for surface or other analyses of NPs are identified, including challenges associated with reproducible synthesis and functionalization of the particles as well as their dynamic nature. The relevant information about the sample preparation processes, along with analysis details and data that need to be added to the collection of material provenance information is identified. Examples of protocols that have been successfully used for preparation of nano-objects for surface analysis are included in an annex. KW - Sample preparation KW - Nanoparticles KW - Surface chemistry KW - XPS KW - Dynamic behavior KW - Nano-object KW - Surface analysis PY - 2020 SN - 978-0-12-814182-3 DO - https://doi.org/10.1016/B978-0-12-814182-3.00018-3 SP - 295 EP - 347 PB - Elsevier CY - Amsterdam AN - OPUS4-50186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinrich, Thomas A1 - Darlatt, Erik A1 - Lippitz, Andreas A1 - Müller, S. A1 - Schalley, C. A1 - Unger, Wolfgang T1 - Systematic XP and NEXAFS spectroscopy studies of (ter-)pyridineterminated self-assembled monolayers and their addressability for functional molecules N2 - The chemical composition of surfaces functionalized with self-assembled monolayers (SAMs) is an important parameter that determines their performance in a broad range of applications, from immobilizing molecular machines to initiation and growth control of MOFs (Metal-Organic Frameworks). In this article, a critical Survey of XPS (X-ray photoelectron spectroscopy) and NEXAFS (near edge X-ray absorption fine structure) spectroscopy data for pyridine-functionalized monolayers on gold surfaces is presented to compile correlations that have been indiscernible before. Monolayers with aromatic backbones are compared to monolayers with aliphatic backbones. Monolayers with pyridine end-groups are compared to mixed monolayers formed terpyridine-functionalized by molecules end-groups and non-functionalized molecules. Thiol-oxidation during ageing of the SAMs in air is addressed. And finally, the addressability of the SAMs for the deposition of metal-ions and organic molecules is investigated and compared. This work consequently delivers a comprehensive set of spectroscopic data of (ter-)pyridine-terminated SAMs and their performance as template for the preparation of functional multilayers of macrocycles exhibiting a preferential orientation. KW - (ter-)pyridineterminated self-assembled monolayer KW - X-ray Photoelectron Spectroscopy (XPS) KW - NEXAFS PY - 2019 DO - https://doi.org/10.1016/j.elspec.2019.03.011 VL - 233 SP - 28 EP - 37 PB - Elsevier B.V. AN - OPUS4-48018 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Horn, Wolfgang A1 - Jann, Oliver A1 - Brosig, L. A1 - Müller, B. A1 - Mertes, A. A1 - de Lima Vasconcelos, S. T1 - Emissions- und geruchsarme Bauprodukte für energieeffiziente Gebäude – Entwicklung von Anforderungen und Konzepten für den Blauen Engel aus Klimaschutzsicht N2 - Menschen, die in der gemäßigten Klimazone leben, verbringen bis zu 90% ihres Lebens in Innenräumen. Deshalb hat das Innenraumklima eine sehr große Bedeutung für deren Wohlergehen, Gesundheit und Leistungsfähigkeit. In Deutschland wird ca. 40% der eingesetzten Primärenergie für das Heizen, Kühlen und Klimatisieren der Innenräume verwendet. Das Forschungsvorhaben hat eine Laufzeit vom Oktober 2013 bis März 2017. Es wird in Kooperation mit der Bundesanstalt für Materialforschung und –prüfung (BAM) und der Hochschule für Technik und Wirtschaft Berlin (HTW Berlin) durchgeführt. Die HTW Berlin koordiniert das Projekt. Die Rheinisch-Westfälische Technische Hochschule Aachen (RWTH) wird teilweise über einen Auftrag in das Projekt integriert. Ziel des Projektes ist es Baustoffe auf ihre Geruchsemissionen zu untersuchen, um Bauprodukte mit niedrigen Emissionen und Gerüchen identifizieren zu können. Den Verbraucherinnen und Verbrauchern wird somit die Möglichkeit gegeben emissions- und geruchsarme Baustoffe zu wählen. Die Aufgabenstellung des Projektes ist nachfolgend aufgeführt: Arbeitspaket 1: Geruchsmessung bei Produkten mit dem Blauen Engel (siehe Kapitel 4 und 5); Arbeitspaket 2: Untersuchung von Vergleichsmaßstäben (siehe Kapitel 6); Arbeitspaket 3: Untersuchung der Linearität der Acetonskala (siehe Kapitel 7); Arbeitspaket 4: Erstellung einer Produktdatenbank (siehe Kapitel 8). Die Geruchsuntersuchung ist in den Vergabekriterien für den „Blauen Engel“ für textile Bodenbeläge (RAL UZ-128) eingebunden worden. Aus den weiteren Untersuchungen sind für die Normung wichtige Erkenntnisse erarbeitet worden. KW - VOC Emissionen KW - Geruch KW - Bewertung KW - Innenraumluftqualtität KW - Bodenbeläge PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487223 UR - https://www.umweltbundesamt.de/publikationen/emissions-geruchsarme-bauprodukte-fuer UR - https://www.umweltbundesamt.de/sites/default/files/medien/1410/publikationen/2019-08-20-texte_92-2019_emissionsarme-bauprodukte.pdf SN - 1862-4804 VL - 92 SP - 1 EP - 106 PB - Umweltbundesamt CY - Dessau-Roßlau AN - OPUS4-48722 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - de Lima Vasconcelos, S. A1 - Sattler, M. A1 - Müller, B. A1 - Plehn, W. A1 - Horn, Wolfgang T1 - The Influence of textile floor coverings on the indoor air quality N2 - Textile floor coverings are often used in offices and residential buildings. Large areas like meeting rooms, cinemas, theaters and hotels are often equipped with such coverings. They contribute to the comfort of the users as they provide high pedaling comfort and sound absorption. The weakness of these building materials is due to the odor emission that is released from the floor covering, which affects the comfort of the users. A bad air quality and the resulting dissatisfaction can lead to lower employee productivity. The research project of the Hochschule für Technik und Wirtschaft Berlin (HTW-Berlin) is promoted by the German Environment Agency (UBA). The project has the following title: Low-emission and low-odor building products for energy-efficient buildings - Development of requirements and concepts for the Blue Angel from a climate protection perspective; investigates the emission and odor behavior of textile floor coverings (Emissions- und geruchsarme Bauprodukte für energieeffiziente Gebäude - Entwicklung von Anforderungen und Konzepten für den Blauen Engel aus Klimaschutzsicht; untersucht das Emissions- und Geruchsverhalten textiler Bodenbeläge). T2 - Clima 2019 Congress CY - Bucharest, Romania DA - 26.05.2019 KW - VOC Emissionen KW - Geruch KW - Bodenbelag KW - AgBB Bewertung PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-487341 DO - https://doi.org/10.1051/e3sconf/201911102051 SN - 2267-1242 VL - 111 SP - 02051-1 EP - 02051-6 PB - EDP Sciences AN - OPUS4-48734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Balzer, R. A1 - Behrens, H. A1 - Schuth, S. A1 - Waurischk, Tina A1 - Reinsch, Stefan A1 - Müller, Ralf A1 - Fechtelkord, M. A1 - Deubener, J. T1 - The influence of H2O and SiO2 on the structure of silicoborate glasses N2 - To understand the impact of dissolved water on structure and properties, four boron-rich glasses of molar compositions 15-x Na2O x CaO 15 SiO2 70 B2O3 (with x=0, 7.5, 10) and 10 Na2O 15 SiO2 75 B2O3 were prepared and subsequently hydrated (up to 8 wt% H2O). Density measurements show a non-linear trend upon hydration implying large structural changes in particular at water contents<2 wt%. Near-infrared spectroscopy shows hydroxyl groups are the dominant species in all glasses upon the entire range of water content. Molecular H2O is detectable only at total water contents>2 wt%. 11B MAS NMR spectra show that the abundance of BO4 species is mainly controlled by ratio of (Na2O+CaO)/B2O3 while incorporation of water plays a minor role. Compared to borate glasses, the efficiency of formation of BO4 tetrahedra is favored by crosslinking of the network by SiO4-units. The glass transition temperatures, determined by differential thermal analysis, decreases continuously with water content due to breakage of B-O-B bonds by hydrolysis. However, compared to Silicates and aluminosilicates, the effect of dissolved water is less pronounced which can be explained by weaker B-O-B bonds in comparison to Si-O-Si bonds. KW - High pressure KW - Water speciation KW - Silicoborate glasses KW - Infrared spectroscopy KW - NMR spectroscopy PY - 2019 DO - https://doi.org/10.1016/j.jnoncrysol.2019.05.030 VL - 519 SP - 38 EP - 51 PB - Elsevier B.V. AN - OPUS4-48748 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Akatsuka, C. A1 - Honma, T. A1 - Müller, Ralf A1 - Reinsch, Stefan A1 - Tanaka, S. A1 - Komatsu, T. T1 - Surface crystallization and gas bubble formation during conventional heat treatment in Na2MnP2O7 glass N2 - The crystallization behavior of sodium ion conductive Na2MnP2O7 glass was examined to clarify the crystallization mechanism. The formation of thermodynamically metastable phase, layered Na2MnP2O7, at the surface of the glass occurred. Heat treatment at 430 °C for 3 h lead to surface crystals of Na2MnP2O7 oriented with the (101) direction perpendicular to the sample surface. As the heat treatment temperature increased, the glass-ceramic samples deformed, and the presence numerous micro bubbles due to dissolved water was detected. KW - Glass-ceramic KW - Crystallization KW - Sodium ion batteries KW - Bubble formation KW - Phosphate PY - 2019 DO - https://doi.org/10.1016/j.jnoncrysol.2019.01.030 VL - 510 SP - 36 EP - 41 PB - Elsevier B.V. AN - OPUS4-49618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Blaeß, Carsten A1 - Müller, Ralf A1 - Poologasundarampilai, G. A1 - Brauer, D. S. T1 - Sintering and concomitant crystallization of bioactive glasses N2 - The sintering of bioactive glasses allows for the preparation of complex structures, such as three‐dimensional porous scaffolds. Such 3D constructs are particularly interesting for clinical applications of bioactive glasses in bone regeneration, as the scaffolds can act as a guide for in‐growing bone cells, allowing for good Integration with existing and newly formed tissue while the scaffold slowly degrades. Owing to the pronounced tendency of many bioactive glasses to crystallize upon heat treatment, 3D scaffolds have not been much exploited commercially. Here, we investigate the influence of crystallization on the sintering behavior of several bioactive glasses. In a series of mixed‐alkali glasses an increased CaO/alkali metal oxide Ratio improved sintering compared to Bioglass 45S5, where dense sintering was inhibited. Addition of small amounts of calcium fluoride helped to keep melting and sintering temperatures low. Unlike glass 13‐93, these new glasses crystallized during sintering but this did not prevent densification. Variation in bioactive glass particle size allowed for fine‐tuning the microporosity resulting from the sintering process. KW - Bioactive glass KW - Crystallization KW - Scaffolds KW - Sintering PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-485458 DO - https://doi.org/10.1111/ijag.13477 SN - 2041-1286 VL - 10 IS - 4 SP - 449 EP - 462 PB - Wiley AN - OPUS4-48545 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -