TY - JOUR A1 - Anker, Andy S. A1 - Aspuru-Guzik, Alán A1 - Ben Mahmoud, Chiheb A1 - Bennett, Sophie A1 - Briling, Ksenia R. A1 - Changiarath, Arya A1 - Chong, Sanggyu A1 - Collins, Christopher M. A1 - Cooper, Andrew I. A1 - Crusius, Daniel A1 - Darmawan, Kevion K. A1 - Das, Basita A1 - David, Nicholas A1 - Day, Graeme M. A1 - Deringer, Volker L. A1 - Duarte, Fernanda A1 - Eardley-Brunt, Annabel A1 - Evans, Matthew L. A1 - Evans, Rob A1 - Fairlamb, Ian A1 - Franklin, Barnabas A. A1 - Frey, Jeremy A1 - Ganose, Alex M. A1 - Goulding, Mark A1 - Hafizi, Roohollah A1 - Hakkennes, Matthijs A1 - Hickey, Niamh A1 - James, Gillian A1 - Jelfs, Kim E. A1 - Kalikadien, Adarsh V. A1 - Kapil, Venkat A1 - Koczor-Benda, Zsuzsanna A1 - Krammer, Ferdinand A1 - Kulik, Heather J. A1 - Kumar, Vishank A1 - Kuttner, Christian A1 - Lam, Erwin A1 - Lou, Yuchen A1 - Mante, Eltjo A1 - Martin, Jennie A1 - Mroz, Austin M. A1 - Nematiaram, Tahereh A1 - Pare, Charles W. P. A1 - Patra, Sarbani A1 - Proudfoot, James A1 - Ruscic, Branko A1 - Ryder, Matthew R. A1 - Sakaushi, Ken A1 - Saßmannshausen, Jörg A1 - Savoie, Brett M. A1 - Schneider, Nadine A1 - Schwaller, Philippe A1 - Skjelstad, Bastian Bjerkem A1 - Sun, Wenhao A1 - Szczypiński, Filip T. A1 - Torrisi, Steven A1 - Ueltzen, Katharina A1 - Vishnoi, Shubham A1 - Walsh, Aron A1 - Wang, Xinwei A1 - Wilson, Chloe A1 - Wu, Ruiqi A1 - Zeitler, Jakob T1 - Discovering structure–property correlations: General discussion N2 - This article is a discussion of the paper "Web-BO: Towards increased accessibility of Bayesian optimisation (BO) for chemistry" by Austin M. Mroz, Piotr N. Toka, Ehecatl Antonio del Río Chanona and Kim E. Jelfs (Faraday discussions, 2025, 256, 221-234). KW - Materials design KW - Machine learning KW - Automation KW - Materials discovery PY - 2025 DO - https://doi.org/10.1039/d4fd90062f SN - 1359-6640 SN - 1364-5498 VL - 256 IS - Themed collection: Data-driven discovery in the chemical sciences SP - 373 EP - 412 PB - Royal Society of Chemistry (RSC) CY - Cambridge AN - OPUS4-62208 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Albornoz, Ricardo Valencia A1 - Antypov, Dmytro A1 - Blanke, Gerd A1 - Borges, Itamar A1 - Marulanda Bran, Andres A1 - Cheung, Joshua A1 - Collins, Christopher M. A1 - David, Nicholas A1 - Day, Graeme M. A1 - Deringer, Volker L. A1 - Draxl, Claudia A1 - Eardley-Brunt, Annabel A1 - Evans, Matthew L. A1 - Fairlamb, Ian A1 - Fieseler, Kate A1 - Franklin, Barnabas A. A1 - George, Janine A1 - Grundy, Joanna A1 - Johal, Jay A1 - Kalikadien, Adarsh V. A1 - Kapil, Venkat A1 - Kotopanov, Lyubomir A1 - Kumar, Vishank A1 - Kuttner, Christian A1 - Lederbauer, Magdalena A1 - Ojeda-Porras, Andrea Carolina A1 - Pang, Jiayun A1 - Parkes, Michael A1 - Pemberton, Miles A1 - Ruscic, Branko A1 - Ryder, Matthew R. A1 - Sakaushi, Ken A1 - Saleh, Gabriele A1 - Savoie, Brett M. A1 - Schwaller, Philippe A1 - Skjelstad, Bastian Bjerkem A1 - Sun, Wenhao A1 - Taniguchi, Takuya A1 - Taylor, Christopher R. A1 - Torrisi, Steven A1 - Vishnoi, Shubham A1 - Walsh, Aron A1 - Wu, Ruiqi T1 - Discovering trends in big data: General discussion N2 - This article is a discussion of the paper "Specialising and analysing instruction-tuned and byte-level language models for organic reaction prediction" by Jiayun Pang and Ivan Vulić (Faraday discussions, 2025, 256, 413-433). KW - Automation KW - Big data KW - Machine learning KW - Materials design KW - Chemically complex materials PY - 2025 DO - https://doi.org/10.1039/D4FD90063D SN - 1359-6640 SN - 1364-5498 VL - 256 IS - Themed collection: Data-driven discovery in the chemical sciences SP - 520 EP - 550 PB - Royal Society of Chemistry (RSC) CY - Cambridge AN - OPUS4-62652 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zaiser, E. A1 - Fantin, Andrea A1 - Manzoni, Anna Maria A1 - Hesse, René A1 - Többens, D. M. A1 - Hsu, W.-C. A1 - Murakami, H. A1 - Yeh, A.-C. A1 - Pavel, M. J. A1 - Weaver, M. L. A1 - Zhu, H. A1 - Wu, Y. A1 - Vogel, F. T1 - Elucidating hierarchical microstructures in high entropy superalloys: An integrated multiscale study N2 - In this study, we examine a high entropy superalloy (HESA-Y1: Ni49.37Co20Cr7Fe4Al11.6Ti6Re1Mo0.5W0.5Hf0.03 at%), focusing on hierarchical microstructure formation and its effects on mechanical properties. Thermodynamic modeling using Thermo-Calc predicts equilibrium phase fractions, compositions, and transition temperatures,which are validated by experimental data from differential scanning calorimetry (DSC). Transmission electronmicroscopy (TEM) reveals that secondary aging induces nanometer-sized γ particles within γ’ precipitates, forming a hierarchical γ/γ’ microstructure. Atom probe tomography (APT) confirms supersaturation of γ’ precipitates with γ-forming elements (Co, Cr, Fe), driving γ particle formation, and measures interfacial widths between γ’ and γ phases. Partitioning coefficients derived from APT align with Thermo-Calc predictions for most elements. Vickers microhardness testing shows an increase of about 50 HV in the hierarchical microstructure compared to the conventional one. In situ synchrotron X-ray diffraction (XRD) from 25 to 750 ◦C determines a small, negative lattice misfit δ between γ and γ’ phases, suggesting enhanced microstructural stability, consistent with Thermo-Calc calculations. Our methodological approach enables measurement of the unconstrained lattice parameter of phase-extracted γ’ in a single-crystal XRD setup. Due to their small size and low volume fraction, γ particles do not produce distinct reflections in the X-ray diffractogram. Elucidating hierarchical microstructures across multiple scales, we establish that the presence of Re and Hf and controlled aging processes lead to enhanced mechanical properties, offering valuable insights for the design of advanced high entropy superalloys. KW - High entropy alloys KW - Transmission electron microscopy KW - X-ray diffraction KW - Superalloy PY - 2025 DO - https://doi.org/10.1016/j.matchar.2024.114642 VL - 220 SP - 1 EP - 13 PB - Elsevier Inc. AN - OPUS4-62348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bates, J. S. A1 - Martinez, J. J. A1 - Hall, M. N. A1 - Al-Omari, A. A. A1 - Murphy, E. A1 - Zeng, Y. A1 - Luo, F. A1 - Primbs, M. A1 - Menga, D. A1 - Bibent, N. A1 - Sougrati, M. T. A1 - Wagner, F. E. A1 - Atanassov, P. A1 - Wu, G. A1 - Strasser, P. A1 - Fellinger, Tim-Patrick A1 - Jaouen, F. A1 - Root, T. W. A1 - Stahl, S. S. T1 - Chemical Kinetic Method for Active-Site Quantification in Fe-N‑C Catalysts and Correlation with Molecular Probe and Spectroscopic Site-Counting Methods N2 - Mononuclear Fe ions ligated by nitrogen (FeNx) dispersed on nitrogen-doped carbon (Fe-N-C) serve as active centers for electrocatalytic O2 reduction and thermocatalytic aerobic oxidations. Despite their promise as replacements for precious metals in a variety of practical applications, such as fuel cells, the discovery of new Fe-N-C catalysts has relied primarily on empirical approaches. In this context, the development of quantitative structure−reactivity relationships and benchmarking of catalysts prepared by different synthetic routes and by different laboratories would be facilitated by the broader adoption of methods to quantify atomically dispersed FeNx active centers. In this study, we develop a kinetic probe reaction method that uses the aerobic oxidation of a model hydroquinone substrate to quantify the density of FeNx centers in Fe-N-C catalysts. The kinetic method is compared with low-temperature Mössbauer spectroscopy, CO pulse chemisorption, and electrochemical reductive stripping of NO derived from NO2 − on a suite of Fe-N-C catalysts prepared by diverse routes and featuring either the exclusive presence of Fe as FeNx sites or the coexistence of aggregated Fe species in addition to FeNx. The FeNx site densities derived from the kinetic method correlate well with those obtained from CO pulse chemisorption and Mössbauer spectroscopy. The broad survey of Fe-N-C materials also reveals the presence of outliers and challenges associated with each site quantification approach. The kinetic method developed here does not require pretreatments that may alter active-site distributions or specialized equipment beyond reaction vessels and standard analytical instrumentation. KW - Active-Site Quantification PY - 2023 DO - https://doi.org/10.1021/jacs.3c08790 SP - 1 EP - 16 PB - ACS Publications AN - OPUS4-58889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Noble, J.E. A1 - Wang, L. A1 - Cerasoli, E. A1 - Knight, A.E. A1 - Porter, R.A. A1 - Gray, E. A1 - Howe, C. A1 - Hannes, E. A1 - Corbisier, P. A1 - Wang, J. A1 - Wu, L. A1 - Altieri, I. A1 - Patriarca, M. A1 - Hoffmann, Angelika A1 - Resch-Genger, Ute A1 - Ebert, B. A1 - Voigt, Jan A1 - Shigeri, Y. A1 - Vonsky, M.S. A1 - Konopelko, L.A. A1 - Gaigalas, A.K. A1 - Bailey, M. J. A. T1 - An international comparability study to determine the sources of uncertainty associated with a non-competitive sandwich fluorescent ELISA KW - ELISA KW - Fluorescence KW - Interferon KW - Uncertainty KW - Round Robin KW - Immunoassay KW - Quality assurance KW - Fluorescein PY - 2008 SN - 1434-6621 SN - 1437-8523 VL - 46 IS - 7 SP - 1033 EP - 1045 PB - De Gruyter CY - Berlin AN - OPUS4-18283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Anker, Andy S. A1 - Aspuru-Guzik, Alán A1 - Bechtel, Tim A1 - Bigi, Filippo A1 - Briling, Ksenia R. A1 - Das, Basita A1 - David, Nicholas A1 - Day, Graeme M. A1 - Deringer, Volker L. A1 - Dyer, Matthew A1 - Eardley-Brunt, Annabel A1 - Evans, Matthew L. A1 - Evans, Rob A1 - Franklin, Barnabas A. A1 - Ganose, Alex M. A1 - George, Janine A1 - Goulding, Mark A1 - Hickey, Niamh A1 - James, Gillian A1 - Kalikadien, Adarsh V. A1 - Kapil, Venkat A1 - Kulik, Heather J. A1 - Kumar, Vishank A1 - Kuttner, Christian A1 - Lam, Erwin A1 - Lederbauer, Magdalena A1 - Lou, Yuchen A1 - Martin, Jennie A1 - Marulanda Bran, Andres A1 - Mathea, Miriam A1 - Pickard, Chris J. A1 - Ruscic, Branko A1 - Ryder, Matthew R. A1 - Sabanza Gil, Victor A1 - Schwaller, Philippe A1 - Segler, Marwin H. S. A1 - Sun, Wenhao A1 - Tanovic, Sara A1 - Treyde, Wojtek A1 - Walsh, Aron A1 - Wu, Ruiqi T1 - Discovering synthesis targets: General discussion N2 - This article is a discussion of the paper "Analysis of uncertainty of neural fingerprint-based models" by Christian W. Feldmann, Jochen Sieg and Miriam Mathea (Faraday discussions, 2025, DOI: 10.1039/D4FD00095A). KW - Automation KW - Materials acceleration platforms KW - Machine learning KW - Materials design KW - Materials discovery KW - Density functional theory KW - Ab initio PY - 2025 DO - https://doi.org/10.1039/D4FD90064B SN - 1359-6640 SN - 1364-5498 VL - 256 IS - Themed collection: Data-driven discovery in the chemical sciences SP - 639 EP - 663 PB - Royal Society of Chemistry (RSC) CY - Cambridge AN - OPUS4-62317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Z. A1 - Wegner, Karl David A1 - Stiegler, L. M. S. A1 - Zhou, X. A1 - Rezvani, A. A1 - Odungat, A. S. A1 - Zubiri, B. A. A1 - Wu, M. A1 - Spiecker, E. A1 - Walter, J. A1 - Resch-Genger, Ute A1 - Segets, D. T1 - Optimizing the Shelling Process of InP/ZnS Quantum Dots Using a Single-Source Shell Precursor: Implications for Lighting and Display Applications N2 - InP/ZnS core/shell quantum dots (QDs), recognized as highly promising heavy-metal-free emitters, are increasingly being utilized in lighting and display applications. Their synthesis in a tubular flow reactor enables production in a highly efficient, scalable, and reproducible manner, particularly when combined with a single-source shell precursor, such as zinc diethyldithiocarbamate (Zn(S2CNEt2)2). However, the photoluminescence quantum yield (PLQY) of QDs synthesized with this route remains significantly lower compared with those synthesized in batch reactors involving multiple steps for the shell growth. Our study identifies the formation of absorbing, yet nonemissive ZnS nanoparticles during the ZnS shell formation process as a main contributing factor to this discrepancy. By varying the shelling conditions, especially the shelling reaction temperature and InP core concentration, we investigated the formation of pure ZnS nanoparticles and their impact on the optical properties, particularly PLQY, of the resultant InP/ZnS QDs through ultraviolet−visible (UV−vis) absorption, steady-state and time-resolved photoluminescence (PL) spectroscopy, scanning transmission electron microscopy (STEM), and analytical ultracentrifugation (AUC) measurements. Our results suggest that process conditions, such as lower shelling temperatures or reduced InP core concentrations (resulting in a lower external surface area), encourage homogeneous nucleation of ZnS. This reduces the availability of shell precursors necessary for effective passivation of the InP core surfaces, ultimately resulting in lower PLQYs. These findings explain the origin of persistently underperforming PLQY of InP/ZnS QDs synthesized from this synthesis route and suggest further optimization strategies to improve their emission for lighting and display applications. KW - Nano KW - Particle KW - Synthesis KW - InP KW - Shell KW - Fluorescence KW - Quantum yield KW - ZnS KW - Semiconductor KW - Quantum dot KW - Flow reactor KW - Method KW - AUC KW - Size KW - Automation KW - Sensor PY - 2024 DO - https://doi.org/10.1021/acsanm.4c05265 SN - 2574-0970 VL - 7 IS - 20 SP - 24262 EP - 24273 PB - ACS Publications AN - OPUS4-61518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Song, Z. A1 - He, T. A1 - Li, M. A1 - Wu, Dejian A1 - You, F. T1 - Self-sustaining smoldering as a novel disposal approach for food waste with high moisture content N2 - This work aims to explore the self-sustaining smoldering treatment (SSST) for the destruction of food waste. The food waste used in this work mainly consists of cereal, vegetable, and meat. To examine the processing procedures and parameters, three experimental groups (raw food waste, food-waste paste and food-waste paste blended with anthracite) and five variables (moisture content, sand size, sand-to-food waste ratio, air flow and food waste-to-coal ratio) were extensively investigated. Results show that raw food waste with 40% moisture content can be disposed by SSST with the mass destruction ratio over 90%. However, the robustness of SSST for raw food waste is constrained by the heterogeneous issue due to a variety of components and sizes of food waste. This issue is addressed through stir pre-processing of raw food waste as food-waste paste. The robustness of SSST for food waste is significantly further enhanced only if a slight mass fraction of anthracite (<20% of raw food waste) is supplemented. This provides an alternative solution for employing SSST for raw food waste with very high moisture content. KW - Food waste KW - Waste disposal KW - Smoldering combustion KW - Self-sustaining propagation PY - 2021 DO - https://doi.org/10.1016/j.fuproc.2021.107144 SN - 0078-3820 VL - 228 SP - 1 EP - 10 PB - Elsevier B.V. AN - OPUS4-55053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, J. A1 - Gong, M. A1 - Zhang, W. A1 - Mehmood, Asad A1 - Zhang, J. A1 - Ali, G. A1 - Kucernak, A. T1 - Simultaneously incorporating atomically dispersed Co-Nₓ sites with graphitic carbon layer-wrapped Co₉S₈ nanoparticles for oxygen reduction in acidic electrolyte N2 - A facile yet robust synthesis is reported herein to simultaneously incorporate atomically dispersed Co-Nₓ sites with graphitic layer-protected Co₉S₈ nanoparticles (denoted as Co SACs+Co₉S₈) as an efficient electrocatalyst for oxygen reduction in acidic solution. The Co SACs+Co₉S₈ catalyst shows low H₂O₂ selectivity (∼5 %) with high half-wave potential (E1/2) of ∼0.78 V(RHE) in 0.5 M H₂SO₄. The atomic sites of the catalyst were quantified by a nitrite stripping method and the corresponding site density of the catalyst is calculated to be 3.2×10¹⁸ sites g⁻¹. Besides, we also found the presence of a reasonable amount of Co₉S₈ nanoparticles is beneficial for the oxygen electrocatalysis. Finally, the catalyst was assembled into a membrane electrode assembly (MEA) for evaluating its performance under more practical conditions in proton exchange membrane fuel cell (PEMFC) system. KW - Co−N-Cs KW - Fuel cells KW - Single-atom catalysts KW - Oxygen reduction reaction KW - PGM-free catalysts PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575993 DO - https://doi.org/10.1002/celc.202300110 SN - 2196-0216 VL - 10 IS - 12 SP - 1 EP - 9 PB - Wiley-VCH CY - Weinheim AN - OPUS4-57599 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, Guang Mei A1 - Schartel, Bernhard A1 - Kleemeier, M. A1 - Hartwig, A. T1 - Flammability of layered silicate epoxy nanocomposites combined with low-melting inorganic ceepree glass N2 - Tetraphenylphosphonium modified layered silicate epoxy nanocomposite (EP/TPPMMT) combined with low-melting silicate glass, Ceepree (CP) is investigated by thermal analysis, flammability tests and cone calorimeter at different heat fluxes. Adding CP and TPPMMT does not change the pyrolysis apart from increasing inorganic residue. The total heat evolved (THE) is changed insignificantly, as neither relevant additional carbonaceous charring nor flame inhibition occurs. However, flame retardancy is clearly observed due to an inorganic-carbonaceous surface protection layer. The peak heat released rate (PHRR) is reduced by around 32–42% when 5 wt% TPPMMT is added, and 51–63% when 10 wt% CP is added. PHRR reduction less than expected is observed when both additives are combined. The reduction is greater than that achieved by using TPPMMT but less than when only CP is used. The morphology of fire residue is investigated by scanning electron microscope on different length scales and turns out to be the key to understanding the efficiency of flame retardancy. The fire residue of EP/CP shows a layered structure, whereas separated columns limit the barrier properties for EP/5%TPPMMT on the micrometer scale. Columns dominating the fire residue structure of EP/5%TPPMMT/10%CP deteriorate the fire retardancy, whereas a more integral structure at the top of the residue causes the improvement over EP/5%TPPMMT. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers KW - Flame retardancy KW - Nanocomposites KW - Low melting glasses KW - Epoxy resin KW - Ceepree PY - 2012 DO - https://doi.org/10.1002/pen.22111 SN - 0032-3888 SN - 1548-2634 VL - 52 IS - 3 SP - 507 EP - 517 PB - Wiley CY - Hoboken, NY AN - OPUS4-25590 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, Guang Mei A1 - Schartel, Bernhard A1 - Yu, D. A1 - Kleemeier, M. A1 - Hartwig, A. T1 - Synergistic fire retardancy in layered-silicate nanocomposite combined with low-melting phenysiloxane glass N2 - Tetraphenyl phosphonium-modified layered silicate (LS) and low-melting phenylsiloxane glass (G) are combined for more efficient halogen-free flame retardancy in epoxy resin (EP_LSG). Particularly, the peak heat release rate (PHRR) is decreased (by up to 60%), but levels off at additive concentrations ≥10 wt%. The performance of EP_LSG is compared to EP_LS and EP_G assuming an absolute and a relative flame retardancy effect, respectively, and based on the same amount of each filler and, alternatively, with EP_G containing the same overall amount of filler. EP_LSG behaves close to superposition but shows a strong tendency toward synergism due to a superior structural integrity of the fire residues. Apart from LS, adding G in particular is a promising approach when its content is ≤5 wt%, as is LSG for ≥10 wt%. KW - Low-melting glass KW - Layered silicate KW - Flame retardancy KW - Nanocomposites KW - Epoxy resin PY - 2012 DO - https://doi.org/10.1177/0734904111422417 SN - 0734-9041 SN - 1530-8049 VL - 30 IS - 1 SP - 69 EP - 87 PB - Sage CY - London AN - OPUS4-25359 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, Guang Mei A1 - Schartel, Bernhard A1 - Bahr, Horst A1 - Kleemeier, M. A1 - Yu, D. A1 - Hartwig, A. T1 - Experimental and quantitative assessment of flame retardancy by the shielding effect in layered silicate epoxy nanocomposites N2 - A quantitative experimental assessment of flame retardancy by the heat shielding in epoxy layered silicate nanocomposite (EP/TPPMMT) is presented. Online heat flux measurements and temperature monitoring within the specimen are performed during the burning in the cone calorimeter. For EP the surface layer equals a pyrolysis front. The reradiation by the hot surface corresponds to the fourth power of the pyrolysis temperature. The surface reradiation (around 10 kW m-2) is thus fairly invariable over burning time and different external heat fluxes. Further, the thermal feedback of the flame is approximated to 20 kW m-2 for both EP and EP/TPPMMT and invariable over different irradiations. Thus the net heat fluxes transformed to the fuel release rate within the pyrolysis front of EP are increased to 45–80 kW m-2 when irradiations of 35–70 kW m-2 are applied. For a residue-forming EP/TPPMMT the surface temperature and thus the reradiation (42–68 kW m-2) crucially increases compared to EP and with increasing irradiation. The net heat fluxes are reduced to 13–22 kW m-2 accordingly. This quantitative assessment of the heat shielding in EP/TPPMMT goes along with proportional and consistent improvement in the fire performance, such as the pyrolysis front velocity, the heat release rate (HRR) characteristics such as averaged and quasi-steady-state HRR and the peak HRR (PHRR). The heat shielding is proven to be the only major flame retardancy effect occurring in nanocomposites based on non-charring polymers. KW - Nanocomposites KW - Heat shielding KW - Flame retardancy KW - Shielding effect PY - 2012 DO - https://doi.org/10.1016/j.combustflame.2012.07.003 SN - 0010-2180 SN - 1556-2921 VL - 159 IS - 12 SP - 3616 EP - 3623 PB - Elsevier Inc. CY - New York, NY AN - OPUS4-26841 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Martin A1 - Wu, D. A1 - Norman, F. A1 - Vanierschot, M. A1 - Verplaetsen, F. A1 - Berghmans, J. A1 - van den Bulck, E. T1 - Numerical investigation on the self-ignition behaviour of coal dust accumulations: The roles of oxygen, diluent gas and dust volume N2 - Self-ignition of coal dust deposits poses a higher risk of fires in oxygen-enriched oxy-fuel combustion systems. In this work, we develop a numerical method, using the commercial software COMSOL Multiphysics, to investigate self-ignition behaviour of coal dust accumulations with a main emphasis on the roles of oxygen, diluent gas and dust volume. A one-step 2nd-order reaction kinetic model considering both coal density and oxygen density is used to estimate reaction rate using the kinetic parameters from previously conducted hot-oven tests. This model is validated to predict the transient temperature and concentration profiles of South African coal dusts until ignition. The computed self-ignition temperatures of dust volumes show a good agreement with experimental results. In addition, it is found that the inhibiting effect of carbon dioxide is comparatively small and oxygen consumption increases dramatically after ignition. Parameter analysis shows that the heating value and kinetic parameters have a comparatively pronounced effect on self-ignition temperature. The model provides a satisfactory explanation for the dependence of self-ignition behaviour on gas atmospheres, thus helping to further understand the fire risk of self-ignition in oxy-fuel combustion systems. KW - Ignition temperature KW - Oxy-fuel combustion KW - Fire safety KW - Self-ignition KW - Numerical simulation PY - 2017 DO - https://doi.org/10.1016/j.fuel.2016.10.063 SN - 0016-2361 SP - 500 EP - 510 AN - OPUS4-37885 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Fischer, C. A1 - Wu, J. A1 - Meyer, U. A1 - Kong, B. A1 - Schmidt, Martin A1 - Wuttke, M. A1 - Drebenstedt, C. A1 - Barth, Uli A1 - Rüter, H. T1 - Eight years of successful bilateral cooperation: Milestones of sino-german research T2 - 2nd International conference on coal fire research (ICCFR2) CY - Berlin, Germany DA - 2010-05-19 KW - Underground coal fires KW - Sino-german cooperation PY - 2010 SN - 978-3-86012-397-3 IS - Introduction SP - 3 EP - 18 AN - OPUS4-21460 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yu, D. A1 - Kleemeier, M. A1 - Wu, Guang Mei A1 - Schartel, Bernhard A1 - Liu, W.Q. A1 - Hartwig, A. T1 - The absence of size- dependency in flame retarded composites containing low-melting organic-inorganic glass and clay: Comparison between micro- and nanocomposites N2 - Due to optimised processing of epoxy based composite materials containing a low-melting organic–inorganic glass together with an organo clay, the size of the glass particles could be successfully reduced. Thus truly nano-dispersed composites were obtained, with glass particles in the range of 10 nm to 200 nm. The small particle size allowed efficient interaction of glass particles and organo clay layers. The flame retardancy as well as the thermo-mechanical properties were tested, and the results showed that the low-melting glass led to a remarkable reduction of peak heat release rate by forming an enhanced barrier layer. Nevertheless no further improvement could be achieved by lowering the particle size to the nanometre region. For good flame retardancy a microdispersion of the low-melting glass was already sufficient. KW - Epoxy resin KW - Nanocomposites KW - Low-melting glass KW - Clay KW - Flame retardancy PY - 2011 DO - https://doi.org/10.1016/j.polymdegradstab.2011.06.003 SN - 0141-3910 SN - 1873-2321 VL - 96 IS - 9 SP - 1616 EP - 1624 PB - Elsevier Ltd. CY - London AN - OPUS4-24211 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yu, D. A1 - Kleemeier, M. A1 - Wu, Guang Mei A1 - Schartel, Bernhard A1 - Liu, W.Q. A1 - Hartwig, A. T1 - Phosphorus and silicon containing low-melting organic-inorganic glasses improve flame retardancy of epoxy/clay composites N2 - New low-melting organic–inorganic glassy polymers containing phosphorus and silicon are synthesized by the reaction between phenylphosphonic acid and methyltrichlorosilane or methyltriethoxysilane. They possess both low-softening points and high onset decomposition temperatures, which are favorable for preparing flame retardant composites. Although the glass by itself is sensitive to water, the composites are not significantly affected in that way. For glass/clay/epoxy composites glass transition temperature (Tg) as well as storage modulus increase with the glass amount. The glasses improve flame retardancy significantly due to flame inhibition and the formation of fire residue working as protection layer during burning. The total heat evolved is reduced by 23–28% for using 5–15 wt.% glass and the maximum HRR even by 58–48%. The latter effect decreases with increasing glass amount due to an adulterate residue deformation. The combination of glass and clay is proposed as a possible route to enhance flame retardancy. KW - Clay KW - Epoxy resin KW - Flame retardancy KW - Organic-inorganic polymer KW - Low-melting glass PY - 2011 DO - https://doi.org/10.1002/mame.201100014 SN - 1438-7492 SN - 1439-2054 VL - 296 IS - 10 SP - 952 EP - 964 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-24516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yu, D. A1 - Kleemeier, M. A1 - Wu, Guang Mei A1 - Schartel, Bernhard A1 - Liu, W.Q. A1 - Hartwig, A. T1 - A low melting organic-inorganic glass and its effect on flame retardancy of clay/epoxy composites N2 - A low-melting organic-inorganic glass with a high molecular weight soluble in solvents was synthesized by hydrolytic polycondensation of phenyltriethoxysilane followed by a subsequent heat treatment. Softening point and thermostability were strongly increased after heat treatment. The composites of glass/epoxy and glass/clay/epoxy were studied with respect to their thermal properties, fire behavior and mechanical properties. Heat release rate as measured by cone calorimetry was remarkably reduced in the presence of glass, relative to neat epoxy resin and polymer/clay composites. The combination of glass and clay is a promising approach. It showed mainly superposition and even synergistic effects in some fire properties for higher filler concentrations due to the formation of an enhanced barrier. The structure of residue was investigated by transmission electron microscopy (TEM). KW - Low-melting glass KW - Clay KW - Epoxy resin PY - 2011 DO - https://doi.org/10.1016/j.polymer.2011.03.033 SN - 0032-3861 SN - 1873-2291 VL - 52 IS - 10 SP - 2120 EP - 2131 PB - Elsevier Ltd. AN - OPUS4-23858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, Cheng-Chieh A1 - Weisbrich, S. A1 - Burger, M. A1 - Neitzel, F. ED - Zemčík, R. T1 - A four-point bending test apparatus for measurement- and model-based structural analysis N2 - By means of a small-scale truss bridge, the ability of the Measurement- and Model-based Structural Analysis to detect and localise damage was examined in. Although there was no noteworthy difficulty in detecting damage, it turned out that damage localisation responds sensitively to systematic influences, i.e. non-modelled properties of the mechanical model. Therefore, another experiment is being conducted to re-examine the Measurement- and Model-based Structural Analysis. For this purpose, the bending test is carried out as it has been already theoretically respectively numerically discussed in. In this attempt, the systematic influences such as residual stress are kept as low as possible. T2 - 36th Danubia Adria Symposium on Advances in Experimental Mechanics CY - Pilsen, Czech Republic DA - 24.09.2019 KW - Damage detection KW - Adjustment calculation KW - Finite element method KW - Integrated analysis PY - 2020 UR - http://www.sciencedirect.com/science/article/pii/S2214785320326432 DO - https://doi.org/10.1016/j.matpr.2020.04.028 SN - 2214-7853 VL - 32 IS - 2 SP - 156 EP - 161 PB - Elsevier Ltd. AN - OPUS4-51551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Xu, F. A1 - Ren, H. A1 - Zheng, M. A1 - Shao, X. A1 - Dai, T. A1 - Wu, Y. A1 - Tian, L. A1 - Liu, Y. A1 - Liu, B. A1 - Günster, Jens A1 - Liu, Y. A1 - Liu, Y. T1 - Development of biodegradable bioactive glass ceramics by DLP printed containing EPCs/BMSCs for bone tissue engineering of rabbit mandible defects N2 - Bioactive glass ceramics have excellent biocompatibility and osteoconductivity; and can form direct chemical bonds with human bones; thus, these ceramic are considered as “Smart” materials. In this study, we develop a new type of bioactive glass ceramic (AP40mod) as a scaffold containing Endothelial progenitor cells (EPCs) and Mesenchymal stem cells (BMSCs) to repair critical-sized bone defects in rabbit mandibles. For in vitro experiments: AP40mod was prepared by Dgital light processing (DLP) system and the optimal ratio of EPCs/BMSCs was screened by analyzing cell proliferation and ALP activity, as well as the influence of genes related to osteogenesis and angiogenesis by direct inoculation into scaffolds. The scaffold showed suitable mechanical properties, with a Bending strength 52.7 MPa and a good biological activity. Additionally, when EPCs/BMSCs ratio were combined at a ratio of 2:1 with AP40mod, the ALP activity, osteogenesis and angiogenesis were significantly increased. For in vivo experiments: application of AP40mod/EPCs/BMSCs (after 7 days of in vitro spin culture) to repair and reconstruct critical-sized mandible defect in rabbit showed that all scaffolds were successfully accurately implanted into the defect area. As revealed by macroscopically and CT at the end of 9 months, defects in the AP40mod/EPCs/BMSCs group were nearly completely covered by normal bone and the degradation rate was 29.9% compared to 20.1% in the AP40mod group by the 3D reconstruction. As revealed by HE and Masson staining analyses, newly formed blood vessels, bone marrow and collagen maturity were significantly increased in the AP40mod/EPCs/BMSCs group compared to those in the AP40mod group. We directly inoculated cells on the novel material to screen for the best inoculation ratio. It is concluded that the AP40mod combination of EPCs/BMSCs is a promising approach for repairing and reconstructing large load bearing bone defect. KW - Three-dimensional Bone tissue engineering KW - Endothelial progenitor cell KW - Bone marrow-derived mesenchymal stem cell KW - Bioactive glass scaffold PY - 2020 DO - https://doi.org/10.1016/j.jmbbm.2019.103532 SN - 1751-6161 VL - 103 SP - 103532 EP - 103532 PB - Elsevier Ltd. AN - OPUS4-50491 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fokong, S. A1 - Theek, B. A1 - Wu, Z. A1 - Koczera, P. A1 - Appold, L. A1 - Jorge, S. A1 - Resch-Genger, Ute A1 - van Zandvoort, M. A1 - Storm, G. A1 - Kiessling, F. A1 - Lammers, T. T1 - Image-guided, targeted and triggered drug delivery to tumors using polymer-based microbubbles N2 - Microbubbles (MB) are routinely used contrast agents for functional and molecular ultrasound (US) imaging. In addition, they have been attracting more and more attention for drug delivery purposes, enabling e.g. US-mediated drug delivery across biological barriers and US-induced triggered drug release from the MB shell. The vast majority of efforts in this regard have thus far focused on phospholipid-based soft-shell MB, which are suboptimal for stably incorporating large amounts of drug molecules because of their relatively thin shell. Using poly(butyl cyanoacrylate) (PBCA)-based hard-shell MB, we show here that both hydrophilic (Rhodamine-B) and hydrophobic (Coumarin-6) model drugs can be efficiently and stably entrapped within the ~ 50 nm shell of PBCA MB. In addition, we demonstrate that model drug loading does not negatively affect the acoustic properties of the MB, and that functionalizing the surface of fluorophore-loaded MB with anti-VEGFR2 antibodies enables image-guided and targeted model drug delivery to tumor blood vessels. Finally, we show both in vitro and in vivo that disintegrating VEGFR2-targeted MB with high-mechanical index US pulses leads to high levels of model drug release. Consequently, these findings indicate that polymer-based MB are highly suitable systems for image-guided, targeted and triggered drug delivery to tumors and tumor blood vessels. KW - Ultrasound KW - Microbubbles KW - Fluorescent reporter KW - Drug delivery KW - Tumor targeting KW - Theranostics PY - 2012 DO - https://doi.org/10.1016/j.jconrel.2012.05.007 SN - 0168-3659 SN - 1873-4995 VL - 163 IS - 1 SP - 75 EP - 81 PB - Elsevier CY - Amsterdam AN - OPUS4-27591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zerbst, Uwe A1 - Bruno, Giovanni A1 - Buffière, J.-Y. A1 - Wegener, T. A1 - Niendorf, T. A1 - Wu, T. A1 - Zhang, X. A1 - Kashaev, N. A1 - Meneghetti, G. A1 - Hrabe, Nik A1 - Madia, Mauro A1 - Werner, Tiago A1 - Hilgenberg, Kai A1 - Koukolikova, M. A1 - Prochazka, R. A1 - Dzugan, J. A1 - Möller, B. A1 - Beretta, S. A1 - Evans, Alexander A1 - Wagener, R. A1 - Schnabel, K. T1 - Damage tolerant design of additively manufactured metallic components subjected to cyclic loading: State of the art and challenges N2 - This article is an outcome of a workshop on Fatigue of Additive Manufactured Metallic Components jointly organized by the Federal Institute for Materials Research and Testing (BAM) Berlin, Germany and the National Institute of Standards and Technology (NIST) Boulder, CO, U.S.A. The aim of the workshop was a comprehensive discussion of the specific aspects of additively manufactured (AM) components in regard to failure under cyclic loading. Undoubtedly, a better understanding and the further development of approaches for damage tolerant component design of AM parts are among the most significant challenges currently facing the use of these new technologies. This article presents a thorough overview of the workshop discussions. It aims to provide a review of the parameters affecting the damage tolerance of AM parts with special emphasis on the process parameters intrinsic to the AM technologies, the resulting defects and residual stresses. Based on these aspects, concepts for damage tolerant component design for AM are reviewed and critically discussed. KW - Additive manufacturing KW - Fatigue loading KW - Component assessment KW - Damage tolerance KW - Defects KW - Residual stresses PY - 2021 DO - https://doi.org/10.1016/j.pmatsci.2021.100786 SN - 0079-6425 VL - 121 PB - Elsevier CY - Amsterdam AN - OPUS4-51937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wu, Cheng-Chieh A1 - Weisbrich, S. A1 - Burger, M. A1 - Neitzel, F. T1 - A Four-Point Bending Test Apparatus for Measurement- and Model-based Structural Analysis N2 - By means of a small-scale truss bridge, the ability of the Measurement- and Model-based Structural Analysis to detect and localize damage was examined. Although there was no noteworthy difficulty in detecting damage, it turned out that damage localization responds sensitively to systematic influences, i.e. non-modelled properties of the mechanical model. Therefore, another experiment is being conducted to re-examine the Measurement- and Model-based Structural Analysis. For this purpose, the bending test is carried out as it has been already theoretically respectively numerically discussed. In this attempt, the systematic influences such as residual stress are kept as low as possible. T2 - 36th Danubia Adria Symposium on Advances in Experimental Mechanics CY - Pilsen, Czech Republic DA - 24.09.2019 KW - Damage detection KW - Adjustment calculation KW - Finite element method PY - 2019 SN - 978-80-261-0876-4 SP - 63 EP - 64 CY - Pilsen, Czech Republic AN - OPUS4-49290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wu, Y. A1 - Lu, X. A1 - Cho, J.I.S. A1 - Rasha, L. A1 - Whiteley, M. A1 - Neville, T. P. A1 - Ziesche, R. A1 - Kardjilov, N. A1 - Markötter, Henning A1 - Manke, I. A1 - Zhang, X. A1 - Shearing, P. R. A1 - Brett, D. J. L. T1 - Multi-length scale characterization of compression on metal foam flow-field based fuel cells using X-ray computed tomography and neutron radiography N2 - The mechanical compression of metal foam flow-field based polymer electrolyte fuel cells (PEFCs) is critical in determining the interfacial contact resistance with gas diffusion layers (GDLs), reactant flow and water management. The distinct scale between the pore structure of metal foams and the entire flow-field warrant a multilength scale characterization that combines ex-situ tests of compressed metal foam samples and in-operando analysis of operating PEFCs using X-ray computed tomography (CT) and neutron radiography. An optimal ‘medium’ compression was found to deliver a peak power density of 853 mW/cm². The X-ray CT data indicates that the compression process significantly decreases the mean pore size and narrows the pore size distribution of metal foams. Simulation results suggest compressing metal foam increases the pressure drop and gas velocity, improving the convective liquid water removal. This is in agreement with the neutron imaging results that demonstrates an increase in the mass of accumulated liquid water with minimum compression compared to the medium and maximum compression cases. The results show that a balance between Ohmic resistance, water removal capacity and parasitic power is imperative for the optimal performance of metal foam based PEFCs. KW - Fuel cell KW - Compression effect KW - Metal foam microstructure KW - Neutron radiography KW - X-ray CT PY - 2021 DO - https://doi.org/10.1016/j.enconman.2020.113785 VL - 239 SP - 10 EP - 113785 PB - Elsevier Ltd. AN - OPUS4-53842 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wagner, M.H. A1 - Wu, W. A1 - Liu, Y. A1 - Qian, Q. A1 - Zhang, Y. A1 - Mielke, Werner T1 - Study on Phase Separation of PET/PEN Blends by Dynamic Rheology N2 - Blends of poly(ethylene terephthalate) (PET) and poly(ethylene naphthalate) (PEN) were processed into biaxially drawn films, and samples taken from the bi-oriented films were then investigated by dynamic rheology experiments in the melt state. Storage modulus G and loss modulus G were determined in the frequency range of 10-2-102 rad/s at temperatures between 260 and 300°C. Although the time-temperature superposition (TTS) principle was found to hold in the high frequency regime, a breakdown of TTS was observed at low frequencies, and the terminal behavior of the storage modulus G of the blends departs drastically from the terminal behavior observed for the blend components. This is caused by interfacial surface tension effects. The results indicate that despite the effect of transesterification reactions, the PET/PEN blend systems investigated consist of a microseparate phase of PEN platelets in a matrix of PET. This morphology is produced when the blends are processed into biaxially oriented PET/PEN films, and droplets of PEN are deformed into a lamellar structure consisting of parallel and extended, separate layers. The large interfacial surface area of the bi-oriented PET/PEN blends leads to remarkably strong interfacial tension effects in dynamic rheology measurements. KW - PET/PEN blends KW - Phase separation KW - Dynamic rheology KW - Bi-oriented films KW - Time-temperature superposition KW - Surface tension PY - 2008 DO - https://doi.org/10.1002/app.28156 SN - 0021-8995 SN - 1097-4628 VL - 110 IS - 1 SP - 177 EP - 182 PB - Wiley InterScience CY - Hoboken, NJ AN - OPUS4-17817 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tang, F A1 - Wu, Z A1 - Yang, C A1 - Osenberg, M A1 - Hilger, A A1 - Dong, K A1 - Markötter, Henning A1 - Manke, I A1 - Sun, F A1 - Chen, L A1 - Cui, G T1 - Synchrotron X-ray tomography for rechargeable battery research: Fundamentals, setups and applications N2 - Understanding the complicated interplay of the continuously evolving electrode materials in their inherent 3D states during the battery operating condition is of great importance for advancing rechargeable battery research. In this regard, the synchrotron X-ray tomography technique, which enables non-destructive, multi-scale, and 3D imaging of a variety of electrode components before/during/after battery operation, becomes an essential tool to deepen this understanding. The past few years have witnessed an increasingly growing interest in applying this technique in battery research. Hence, it is time to not only summarize the already obtained battery-related Knowledge by using this technique, but also to present a fundamental elucidation of this technique to boost future studies in battery research. To this end, this review firstly introduces the fundamental principles and experimental Setups of the synchrotron X-ray tomography technique. After that, a user guide to ist application in battery research and examples of its applications in Research of various types of batteries are presented. The current review ends with a discussion of the future opportunities of this technique for next-generation rechargeable batteries research. It is expected that this review can enhance the reader’s understanding of the synchrotron X-ray tomography technique and stimulate new ideas and opportunities in battery research. KW - 3D imaging KW - Batteries KW - Synchrotron X-Ray KW - Tomography PY - 2021 DO - https://doi.org/10.1002/smtd.202100557 VL - 5 IS - 9 SP - 2100557 PB - Wiley-VCH AN - OPUS4-53394 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -