TY - CONF A1 - Li, Wei T1 - Crack propagation in filled and unfilled polymers: Separation of surface energy and irreversible deformation energy N2 - Fiber-reinforced-polymers (FRPs) are in current research focus in the lightweight construction industry, because of their extraordinary characteristics (stiffness and strength-to-density relation). The structure of polymer matrix and the interaction with reinforcement are crucial for optimization of the mechanical and thermal properties of FRPs. Due to the macromolecular chain structure, the mechanical properties of a polymer strongly vary with temperature: Below the glass transition, the chain segments of a polymer are “frozen”. Regarding fracture, the total changed energy during fracture if only dissipates for the generation of the new surfaces. However, in the region of the glass transition, the polymer chain segments start to get “unfrozen”, and the energy is not only required for generating new surfaces, but also for irreversibly deformation. This irreversible deformation is affected by the global temperature and the local temperature near the crack tip, which is affected by the local strain rate and crack propagation velocity. Hence, in this research project, the irreversible deformation of neat and reinforced polymers will be controlled by changing the global temperature as well as the local temperature. With using different fracture experiments, the amount of energy required for creating new surfaces and for the irreversible deformation will be separated. The fracture tests include the conventional tensile test, the macroscopic peel test and the single fiber peel – off test. T2 - PhD Day 2018 of BAM CY - Berlin, Germany DA - 31.05.2018 KW - Crack Propagation KW - Polymer PY - 2018 AN - OPUS4-48471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Linke, Michael T1 - Entwicklung einer magnetischen Anreicherungsmethode für Peptidbibliotheken zur Identifizierung von Proteinbindern N2 - Das Ziel der Arbeit war die Entwicklung einer magnetischen Anreicherungsmethode für eine Bead-basierte Substanzbibliothek zur Identifizierung von Proteinbindern. Im Ramen des Forschungsbelegs wurde bereits eine Anreicherungsmethode für ein Modellsystem einer Peptidbibliothek entwickelt. Das Modellsystem bestand dabei aus zwei verschiedenen Peptiden. Als Positivkontrolle wurde das FLAG-Peptid gewählt, welches selektiv gegen den Anti-FLAG-Antikörper bindet, und ein weiteres Peptid wurde als Negativkontrolle gewählt. Anhand dieses Modellsystems konnte die zuvor entwickelte Anreicherungsmethode von 20.000 auf 1.000.000 Beads vergrößert werden. Hierbei wurde ein Anreicherungsfaktor von 818 und eine gute Wiederfindungsrate von 82% erreicht. KW - Peptide library KW - OBOC library KW - Enrichment KW - Magnetic beads KW - Protein interaction PY - 2018 SP - 1 EP - 86 PB - Humboldt-Universität zu Berlin CY - Berlin AN - OPUS4-54651 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertin, Annabelle T1 - Upper critical solution temperature (UCST)-type thermoresponsive polymers from hydrogen-bonding monomers N2 - UCST-type thermoresponsive polymers (i.e. that phase separate from solution upon cooling) present a tremendous potential not only in aqueous media where they can be used in drug delivery, diagnostic and microfluidic applications, but also in water/alcohol mixtures, where they can be used for instance in sensing systems for alcohol-soluble drugs. However, only a few thermoresponsive polymers have been reported that present an UCST in a relevant temperature range and “green” solvents such as water or ethanol. In this context, acrylamide-based monomers can be very useful building blocks for designing novel non-ionic UCST-type polymers because of their hydrophilic nature (with the appropriate side chain) and propensity to form hydrogen bonds. We will present our latest results on the UCST-type thermoresponsive behaviour of acrylamide- and 2,6-diaminopyridine-based homopolymers and copolymers in water or water/alcohol mixtures, and give some insights about the rational design of UCST polymers relying on H-bonding. T2 - Invited talk (Dr. Jean-Francois Lutz) Institut Charles Sadron CY - Strasbourg, France DA - 26.01.2018 KW - Thermoresponsive polymer KW - UCST-type polymer KW - H bonds KW - Diaminopyridine KW - Acrylamide PY - 2018 AN - OPUS4-44001 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Asadujjaman, Asad A1 - Espinosa de Oliveira, T. A1 - Mukherji, D. A1 - Bertin, Annabelle T1 - Polyacrylamide ‘‘revisited’’: UCST-type reversible thermoresponsive properties in aqueous alcoholic solutions N2 - Combining experiments and all-atom molecular dynamics simulations, we study the conformational behavior of polyacrylamide (PAM) in aqueous alcohol mixtures over a wide range of temperatures. This study Shows that even when the microscopic interaction is dictated by hydrogen bonding, unlike its counterparts that present a lower critical solution temperature (LCST), PAM shows a counterintuitive tunable upper critical solution temperature (UCST)-type phase transition in water/alcohol mixtures that was not reported before. The Phase transition temperature was found to be tunable between 4 and 60 1C by the type and concentration of alcohol in the mixture as well as by the solution concentration and molecular weight of the polymer. In addition, molecular dynamics simulations confirmed a UCST-like behaviour of the PAM in aqueous alcoholic solutions. Additionally, it was observed that the PAM is more swollen in pure alcohol solutions than in 80% alcoholic solutions due to y-like behaviour. Additionally, in the globular state, the size of the aggregates was found to increase with increasing solvent hydrophobicity and polymer concentration of the solutions. Above ist Phase transition temperature, PAM might be present as individual polymer chains in the coil state (r10 nm). As PAM is a widespread polymer in many biomedical applications (gel electrophoresis, etc.), this finding could be of high relevance for many more practical applications in high performance pharmaceuticals and/or sensors. KW - Thermoresponsive polymer KW - UCST-type polymer KW - Polyacrylamide KW - Water/alcohol mixtures PY - 2018 DO - https://doi.org/10.1039/c7sm02424j SN - 1744-6848 SN - 1744-683X VL - 14 IS - 8 SP - 1336 EP - 1343 PB - Royal Society of Chemistry CY - London AN - OPUS4-44002 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kindrachuk, Vitaliy A1 - Titscher, Thomas A1 - Unger, Jörg F. T1 - A Fourier transformation-based method for gradient-enhanced modeling of fatigue N2 - A key limitation of the most constitutive models that reproduce a Degradation of quasi-brittle materials is that they generally do not address issues related to fatigue. One reason is the huge computational costs to resolve each load cycle on the structural level. The goal of this paper is the development of a temporal Integration scheme, which significantly increases the computational efficiency of the finite element method in comparison to conventional temporal integrations. The essential constituent of the fatigue model is an implicit gradient-enhanced formulation of the damage rate. The evolution of the field variables is computed as amultiscale Fourier series in time.On a microchronological scale attributed to single cycles, the initial boundary value problem is approximated by linear BVPs with respect to the Fourier coefficients. Using the adaptive cycle jump concept, the obtained damage rates are transferred to a coarsermacrochronological scale associated with the duration of material deterioration. The performance of the developedmethod is hence improved due to an efficient numerical treatment of the microchronological problem in combination with the cycle jump technique on the macrochronological scale. Validation examples demonstrate the convergence of the obtained solutions to the reference simulations while significantly reducing the computational costs. KW - Accelerated temporal integration KW - Fourier series KW - Gradient-enhanced fatigue model PY - 2018 DO - https://doi.org/10.1002/nme.5740 SN - 1097-0207 SN - 0029-5981 VL - 114 IS - 2 SP - 196 EP - 214 PB - Wiley AN - OPUS4-44008 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Plarre, Rüdiger T1 - Eine kleine Natur- und Kulturgeschichte der Kleidermotte – nebst Möglichkeiten ihrer biologischen Bekämpfung N2 - Zu den unerwünschten Gästen im Museum oder im Haushalt gehört zweifelsohne die Kleidermotte Tineola bisselliella. Es sind die Larven dieses Kleinschmetterlings, die die Schäden verursachen. Neben der konventionellen Schadensabwehr besteht die Möglichkeit, Schlupfwespen zur Bekämpfung der Larven einzusetzen. Der Vortrag rekonstruiert die Natur- und Kulturgeschichte der Kleidermotte anhand ökologischer Studien und historischen Indizien. T2 - Konservierungswissenschaft im Dialog Rathgen Forschungslabor CY - Berlin, Germany DA - 30.01.2018 KW - IPM KW - Museum KW - Biologische Bekämpfung KW - Kulturgut PY - 2018 AN - OPUS4-43988 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Woydt, Mathias T1 - Tribology in hot steam - for waste heat recovery or for energy harvesting - N2 - The wear rates of self-amted alumina couples show that friction as well as wear is largely determined by the above mentioned hydro-thermal conditions. The presence of water and ist amount available in the surrounding system either in liquid or in gaseous from plays a key role for friction and wear behavior and cabe benefical for the tribological profile of steam degradation resistant materials. Hot steam enhances the tribo-chemical formations of oxides and hydroxides on MgO-ZrO2, alumina and antimony impregnated carbon. T2 - 21th International Colloquium Tribology CY - Stuttgart/Ostfildern, Germany DA - 09.01.2018 KW - Friction KW - Alumina KW - Hot steam PY - 2018 AN - OPUS4-43895 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Woydt, Mathias A1 - Wäsche, Rolf A1 - Brandt, Guido A1 - Ehrke, Roman A1 - Yano, S. A1 - Sasaki, S. T1 - Tribology in hot steam for energy recovery N2 - The wear rates of self-mated alumina couples show that friction as well as wear is largely determined by the above-mentioned hydro-thermal conditions. The presence of water and its amount available in the surrounding system either in liquid or in gaseous form plays a key role for friction and wear behavior and can be beneficial for the tribological profile of steam degradation resistant materials. Hot steam enhances the tribo-chemical formations of oxides and hydroxides on MgO-ZrO2 alumina and antimony impregnated carbon. T2 - 21th International Colloquium Tribology CY - Stuttgart/Ostfildern, Germany DA - 09.01.2018 KW - Tribology KW - Friction KW - Alumina KW - Hot steam PY - 2018 SP - 1 EP - 2 AN - OPUS4-43896 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlegel, Moritz-Caspar A1 - Simo, Anne A1 - Palkowski, Carsten A1 - Kniechewski, Arno A1 - Akkerman, Floris T1 - Following the evidence – How quality of appliance components can hint at non-compliance with efficiency requirements N2 - Improving the energy efficiency of products was identified as the most important short-term opportunity to decrease energy consumption and therefore CO2-emission worldwide. More efficient products are created due to technical innovation. Restricting market access to efficient products only and making the most efficient products stand out by energy labelling are legislative approaches to encourage this development. Market surveillance authorities’ checks are fundamental to protect the consumer from wrongly declared goods on the market and ensure fair competition between manufacturers. However, the activities of market surveillance authorities are limited by their financial resources. Testing all product efficiency parameters in an accredited laboratory is very time consuming and cost intensive. In this article, a theoretical concept is presented which can be used to develop screening tests enabling market surveillance authorities to perform product tests with less financial resources. The concept identifies components which lead to non-compliance or make a product less energy efficient with minimum effort. The principle is based on a combination of random product tests, disassembling specific products and comparing components. This represents a new approach in product testing procedures beyond the current market surveillance activities. The concept is being tested within a research project funded by the German government. T2 - EEDAL'17 CY - Irvine, CA, USA DA - 13.09.2017 KW - Methodology KW - Market surveillance KW - Ecodesign PY - 2018 UR - http://publications.jrc.ec.europa.eu/repository/handle/JRC109209 SN - 978-92-79-77173-6 DO - https://doi.org/10.2760/68449 SN - 1018-5593 VL - 3 SP - 1113 EP - 1116 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-43925 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisentraut, Paul T1 - Kunststoffgehalte schnell bestimmen mit der TED-GC-MS N2 - Der Vortrag behandelt die Analyse von Kunststoffen in Umweltproben mit dem thermischen Verfahren TED-GC-MS. Das Verfahren und dessen Funktionsweise werden vorgestellt, erfolgte Optimierungen, Verfahrenskenndaten sowie Möglichkeiten der Quantifizierung behandelt. T2 - Projektübergreifendes Mikroplastikseminar BASEMAN, BONUS MICROPOLL, MiWa CY - Berlin, Germany DA - 16.10.2017 KW - Mikroplastik KW - Analyse KW - TED-GC-MS PY - 2018 AN - OPUS4-43927 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -