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 - CONF A1 - Cornelsen Sampaio Kling, I. A1 - Pauw, Brian Richard A1 - Agudo Jácome, Leonardo A1 - Archanjo, B. S. A1 - Simão, R. A. T1 - Development and characterization of starch film and the incorporation of silver nanoparticles N2 - Starch is one of the biopolymers being used for bioplastic synthesis. For production, starch can be combined with different plasticizers, starches from different plant sources and even with nanomaterials to improve or to add film properties. The challenge of adding these, e.g. in the form of silver nanoparticles (AgNp) is to determine the concentration so as to avoid impairing the properties of the film, agglomeration or altering the visual characteristics of the film. In this study, a starch film synthesis route and the incorporation of silver nanoparticles has been proposed in order not to alter the properties of the film while maintaining the transparency and a clear colour of the starch film. The results showed that the proposed synthesis route is promising, efficient, reproducible, fast and the film has good mechanical properties. T2 - Semana MetalMat & Painal PEMM 2020 CY - Online meeting DA - 23.11.2020 KW - Biofilm KW - Silver nanoparticle KW - Starch KW - Starch nanoparticle PY - 2020 SP - 1 EP - 2 AN - OPUS4-51940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stuff, Maria A1 - Rübner, Katrin A1 - Prinz, Carsten A1 - Rische, N. A1 - Chronz, M. A1 - Kühne, Hans-Carsten ED - Siegesmund, S. ED - Middendorf, B. T1 - Towards a better understanding of tuff stone deterioration N2 - Stone deterioration is the result of a complex interaction of external physical, chemical and biological forces with the mineralogical-petrophysical properties of the stone. With a better understanding of how these properties are linked to material behavior and durability, more effective measures for stone conservation can be developed. Studying these interactions in tuff is particularly complex due to the naturally high heterogeneity of tuff rocks. The first aim of a current research project is to combine the results of recent and older studies on tuff deterioration. Furthermore, the literature overview is complemented by our own investigation of Weibern and Ettringen tuff, with a focus on pore structure characteristics. T2 - STONE - 14th international congress on the deterioration and conservation of stone CY - Meeting was canceled DA - 07.09.2020 KW - Pore structure KW - Weathering KW - Weibern tuff KW - Ettringen tuff PY - 2020 SN - 978-3-96311-172-3 SP - 805 EP - 810 PB - Mitteldeutscher Verlag CY - Halle (Saale) AN - OPUS4-51549 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Legall, Herbert A1 - Bonse, Jörn A1 - Krüger, Jörg T1 - Emission of X-rays during ultrashort pulse laser processing N2 - Ultrashort pulse laser materials processing can be accompanied by the production of X-rays. Small doses per laser pulse can accumulate to significant dose rates at high laser pulse repetition rates which may exceed the permitted X-ray limits for human exposure. Consequently, a proper radiation shielding must be considered in laser machining. A brief overview of the current state of the art in the field of undesired generation of X-ray radiation during ultrashort pulse laser material processing in air is presented. T2 - Lasers in Manufacturing Conference 2021 CY - Online meeting DA - 21.06.2021 KW - Ultra-short pulse laser processing KW - Laser-induced X-ray emission KW - Radiation protection PY - 2021 SP - 1 EP - 5 AN - OPUS4-53866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Florian, Camilo A1 - Deziel, J.-L. A1 - Kirner, Sabrina V. A1 - Siegel, J. A1 - Bonse, Jörn T1 - Femtosecond laser-induced oxidation in the formation of periodic surface structures N2 - Micro- and nanostructuring with laser-induced periodic surface structures (LIPSS) has been demonstrated to be feasible in a wide variety of materials including metals, semiconductors and dielectrics. Suitable processing regimes for flat, curved and complex surfaces have been identified for many materials, allowing the generation of diverse applications in fields such as optics, tribology and medicine, to name a few. A common side effect when producing such structures in air environment is the formation of a thin surface oxide layer in the laser irradiated areas. Previous studies have shown that oxidation plays an important role in the tribological performance for which the structures where created, and very recently it has been shown that the laser-induced oxide graded layers may contribute to the formation of a new type of embedded low-spatial frequency LIPSS (LSFL) with annomalous orientation parallel to the laser polarization, in addition to the appearance of the well-known high-spatial frequency LIPSS (HSFL) at the surface. In this contribution, we explore this effect experimentally for chromium nitride (CrN) irradiated with femtosecond laser pulses and compare the findings to finite-difference time-domain (FDTD) simulations of the intensity distributions at different depth positions. T2 - 2021 Conference on Lasers and Electro-Optics/Europe – European Quantum Electronics Virtual Conferences CY - Munich, Germany DA - 21.06.2021 KW - Femtosecond laser ablation KW - Finite-difference time-domain calculations KW - Laser-induced periodic surface structures (LIPSS) KW - Surface oxidation PY - 2021 SN - 978-1-6654-1876-8 DO - https://doi.org/10.1109/CLEO/Europe-EQEC52157.2021.9542774 VL - 2021 SP - 1 PB - Institute of Electrical and Electronics Engineers (IEEE) CY - Piscataway, NJ, USA AN - OPUS4-53457 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beck, Uwe A1 - Baier, Jennifa A1 - Fischer, Daniel A1 - Griepentrog, Michael A1 - Hertwig, Andreas A1 - Hielscher-Hofinger, Stefan A1 - Stockmann, Jörg Manfred A1 - Weise, Matthias T1 - Mapping und Imaging modifizierter Oberflächen: Generische Kenngrößen, Fehlstellen, Reinigungszustand und Haftfestigkeit N2 - Der Vortrag widmet sich dem Mapping und Imaging modifizierter Oberflächen: generische Kenngrößen, Fehlstellen, Reinigungszustand und Haftfestigkeit. Es werden Untersuchungsmethoden zu ihrer Prüfung dargestellt. T2 - 37. ak-adp 2021 CY - Jena, Germany DA - 16.06.2021 KW - Qualitätssicherung KW - Mapping modifizierter Oberflächen KW - Imaging modifizierter Oberflächen KW - Generische Kenngrößen KW - Haftfestigkeit KW - Klebfestigkeit PY - 2021 SP - 1 EP - 10 AN - OPUS4-52893 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dittmann, Daniel A1 - Saal, L. A1 - Zietzschmann, F. A1 - Mai, M. A1 - Altmann, Korinna A1 - Al-Sabbagh, Dominik A1 - Ruhl, A. S. A1 - Jekel, M. A1 - Braun, U. T1 - Aktivkohlecharakterisierung als weiterer Schlüssel für Adsorptionsprognosen organischer Spurenstoffe in der vierten Reinigungsstufe N2 - In diesem Beitrag wird der Einfluss des Aktivkohleprodukts auf die Adsorption von Spurenstoffen aus Kläranlagenablauf gezeigt und diskutiert. Im zweiten Teil wird das Material Aktivkohle analytisch charakterisiert und die Eigenschaften systematisiert. Die gewonnenen Erkenntnisse werden mit Bezug zu Praxislösungen zusammengefasst. T2 - Wasser 2021 CY - Online meeting DA - 10.05.2021 KW - Aktivkohle KW - Thermogravimetrie KW - Zersetzungsgasanalyse KW - Proximatanalyse PY - 2021 SP - 373 EP - 378 AN - OPUS4-52740 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ermilova, Elena A1 - Weise, Matthias A1 - Hertwig, Andreas T1 - Hybrid optical measurement technique for detection of defects in epitaxially grown 4H-SiC layers N2 - Recent developments in power electronics require the use of new wide bandgap compound semiconductor. We demonstrate the use of the ellipsometry and white light interference microscopy to detect defects in epitaxially grown SiC layers on SiC substrates. Such hybrid optical metrology methods can be used to better understand the mechanism of the development of the defects as well as their effects on the material´s optoelectronic properties. T2 - EOS Annual Meeting (EOSAM 2022) CY - Porto, Portugal DA - 12.09.2022 KW - Imaging ellipsometry KW - White light interference microscopy KW - Wide bandgap compound semiconductor KW - Epitaxially grown 4H-SiC layers PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-561113 DO - https://doi.org/10.1051/epjconf/202226610001 VL - 266 SP - 1 EP - 2 AN - OPUS4-56111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zubia Aranburu, Judith A1 - Cappella, Brunero A1 - Zabala Eguren, A. A1 - Buruaga Lamarain, L. A1 - Aginagalde Lopez, A. A1 - Bonse, Jörn A1 - Schwibbert, Karin T1 - Quantification of the adhesion force of E. coli on Ti via single-cell force spectroscopy N2 - Antibiotic resistance is a growing global problem which poses a massive threat to human health. Although human activity contributes to the acceleration of the process, bacteria have a self-driven stabilisation mechanism to protect themselves from such and other external threats: biofilm formation. Nonetheless, it is the adhesion of a single bacterial cell to a surface that triggers the formation of such network of biomolecules and microorganisms, as well as its hazardous consequences. The main objective of this work was to quantify the adhesion force of a single E. coli cell on a Ti substrate via the AFM-related single-cell force spectroscopy, with both the cell and the substrate material being of high clinical relevance. A set of 25 x 25 force displacement curves was acquired with a maximum force of 3.2 nN without dwell time, yielding a topography map and an adhesion force map that showed to be correlated. A mean adhesion force of 0.85 ± 0.175 nN was measured and the presence of cell appendages on the bacterial cell wall was verified through individual force-displacement curves. Bacterial viability was assessed after the measurements via live/dead staining. T2 - XL Congreso Anual de la Sociedad Española de Ingeniería Biomédica CASEIB 2022 CY - Valladolid, Spain DA - 23.11.2022 KW - Bacteria KW - Atomic force microscopy KW - Force distance curve PY - 2022 SN - 978-84-09-45972-8 SP - 217 EP - 220 AN - OPUS4-57039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bauer, J. A1 - Miclea, P.-T. A1 - Braun, U. A1 - Altmann, Korinna A1 - Turek, M. A1 - Hagendorf, C. T1 - Microplastic detection and analysis in water samples N2 - Microplastic detection in water samples becomes important for tracing microplastic sources. Microplastic may harm desalination facilities by blocking filters and disturbing the marine food chain. Thermo analytical methods such as pyrolysis gas chromatography mass spectroscopy, and spectroscopic methods like (micro) Raman spectroscopy or (micro) Fouriertransform infrared spectroscopy in combination with appropriate filters and sample preparation are suitable for analyzing microplastics on a scale from 1 µm to 1000 µm fast and unambiguous. While the thermo analytical methods are suitable for larger sample volumes, Raman spectroscopy and Fouriertransform infrared spectroscopy are able to detect and analyze single microplastic particles for instance in bottled water. Machine learning algorithms ensure a reliable classification of different plastic materials. T2 - International Conference on Sustainable Energy-Water-Environment Nexus in Desert Climate 2019 CY - Ar-Rayyan, Qatar DA - 02.12.2019 KW - Microplastics KW - Water samples PY - 2022 SP - 111 EP - 113 PB - Springer AN - OPUS4-56240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -