TY - CONF A1 - Zaghdoudi, Maha A1 - Kömmling, Anja A1 - Jaunich, Matthias A1 - Wolff, Dietmar T1 - Analysis of heterogeneous ageing of hnbr o rings N2 - Hydrogenated nitrile butadiene rubber (HNBR) elastomer was thermo-oxidatively aged at different temperatures up to 150°C. Fourier transform infrared spectroscopy (FTIR), compression stress relaxation (CSR) and IRHD microhardness were used to characterise the chemo-mechanical changes of HNBR O-rings during thermo-oxidative ageing. FTIR shows the development of carbonyl, methyl and ester groups but the nitrile content was not affected by ageing. The effect of sample geometry during CSR was investigated. CSR data were converted through integrated kinetic laws. The conversion has proven its sensibility to detect heterogeneous ageing. This was confirmed by the IRHD measurements across the section of O-rings. Oxidation profiles were determined by applying the model of Wise et al. to the IRHD experimental results. T2 - The 2023 Postgraduate Seminar - Advanced Structured Materials CY - Barcelona, Spain DA - 20.02.2023 KW - HNBR KW - Heterogeneous ageing KW - IRHD KW - FTIR KW - CSR PY - 2023 AN - OPUS4-57057 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Hoffmann, Gabi A1 - Rehfeldt, Rainer A1 - Kohl, Anka T1 - Investigations on the degree of damage of polyethylene grades as materials of heating oil storage tanks after a service life of more than 30 years N2 - Tanks for heating oil made of polyethylene grades have been on the market since the early 1970s in Germany. Tank manufacturers recommend the replacement of the tanks after a period of 30 years due to guarantee safety. Polyethylene grades are subject to ageing by alteration of the properties during their life cycle. The degree of ageing and the nature of the degradation process mainly depend on the chemical degradation of the polyethylene, the wall thickness of the tank and the environmental conditions. There are no results available on the long-term behavior of the polyethylene grades, especially after a service life of more than 30 years. The aim of this investigation was the determination of the factual degree of damage in comparison to the uncontaminated polyethylene grades. Material data of the used polyethylene grades are available because the BAM was the competent authority for the tests and expert reports for the approval of these tanks until the middle of the 1990s. The determination of the Melt Flow Rate (MFR) and the Fourier Transmission IR Spectroscopy (FTIR) of tank sections from the bottom, the shell and the roof of 10 segregated heating oil storage tanks produced of polyethylene grades A and B were used as tests methods. The MFR measurements of the tank sections showed differences in the values depending on the weight which was used (5 kg or 21.6 kg). A reduction of the MFR values was measured for most of the sections of tanks made of polyethylene grade B after a service life of the tanks of more than 30 years. This grade is mainly subject to the internal ageing by cross-linkages, increased degree of branched molecules and loss of the plasticizer, and to a lesser extent by oxidative degradation. The FTIR analysis, especially of tank sections of the bottom and the shell showed that the intensity of the CH2 asymmetric and symmetric stretching vibrations in the range: 2800 - 2900 cm-1 and the CH2 bending deformation vibration at 1400 cm-1 increased due chain scissions. The intensity of the carbonyl stretching vibration C=O at 1740 cm-1 is low. The carbonyl index characterizes the degree of oxidation. T2 - EUROCORR 2018 CY - Krakow, Poland DA - 09.09.2018 KW - Heating oil storage tanks KW - Polyethylene KW - Degree of damage KW - Melt Flow Rate (MFR) KW - FTIR PY - 2018 AN - OPUS4-45939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weigel, Sandra A1 - Recknagel, Christoph T1 - FTIR-Charakterisierung von Bitumen - Möglichkeiten und Chancen JF - Jahresmagazin Werkstofftechnik N2 - Das erdölstammige Bindemittel Bitumen weist eine so komplexe Struktur auf, dass diese mit den derzeit eingesetzten Verfahren nur eingeschränkt erfasst werden kann. Eine innovative und vielversprechende Möglichkeit bietet in diesem Zusammenhang die FTIR-Spektroskopie in Kombination mit einer chemometrischen Auswertung, mit der schnell und einfach Aussagen über die Zusammensetzung sowie verschiedenste physikalische und chemische Eigenschaften von bitumenhaltigen Materialien möglich werden. KW - Bitumen KW - FTIR KW - Chemometrie KW - Multivariate Analysemethoden KW - Charakterisierung KW - Identifizierung von Additiven PY - 2021 SN - 1618-8357 SP - 42 EP - 49 PB - ALPHA Informationsgesellschaft mbH CY - Lampertheim AN - OPUS4-53486 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waniek, Tassilo A1 - Ghasem Zadeh Khorasani, Media A1 - Braun, Ulrike A1 - Silbernagl, Dorothee A1 - Sturm, Heinz T1 - New Focus On Boehmite-Reinforced Nanocomposites Molecular Approach With Advanced FTIR-Techniques N2 - By FTIR-study it was possible to proof a chemical reaction between boehmite and the hardener of anhydride cured epoxy resins. Future studies can assume that the chemical environment of the resin system is changed in the surrounding of boehmite nanoparticles. This highly affects especially localized properties. T2 - 6th International Conference on Multifunctional, Hybrid and Nanomaterials CY - Sitges, Spain DA - 11.03.2019 KW - Nanocomposite KW - Boehmite KW - FTIR KW - DRIFTS KW - Epoxy PY - 2019 AN - OPUS4-47785 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwettmann, K. A1 - Stephan, D. A1 - Nytus, N. A1 - Radenberg, M. A1 - Weigel, Sandra T1 - Post carbon road - The endless cycle of bitumen reuse T2 - Proceedings of Eurasphalt and Eurobitumen Congress 2021 N2 - In Germany, the reuse of asphalt has a long tradition. Since the 1980s, the reclaimed asphalt has been recycled achieving a reuse rate of around 90% and thus a very high value in the last years. In the future, instead of the amount, the quality of the reclaimed asphalt will be more important because the recycled asphalt will be reused again and again. Thus, these asphalt mixes are in the second or even third cycle of reuse. Concerning this situation, the question arises if asphalt can be reused several times without any loss in quality. An important factor affecting the asphalt quality is the binder bitumen. During the production, construction and service life, the ageing of this binder occurs causing a hardening of the bitumen. To compensate this hardening, additives for the reclaimed asphalt in terms of rejuvenation agents (rejuvenators) gain in importance. With these rejuvenators, the physical properties of bitumen can be modified e.g. the hardness and the stiffness reduced. However, the mechanism of the rejuvenation agents and the effects of the bitumen chemistry are largely unknown because the composition of the products varies very strongly. But with growing knowledge about these mechanisms and effects of the rejuvenation agents, the chemical composition and thus the physical and ageing behavior of bitumen can be targeted modified by the use of suitable rejuvenators. In this work, the actual results of the project Postcarbone road should be presented including investigations about the chemical and physical mechanisms as well as the efficiency of different rejuvenators. Further, a model for the cyclic reuse of bitumen should be developed. Based on this model, the choice of a suitable rejuvenation agent for the considered bitumen or rather asphalt should be possible. The project Postcarbone road (392670763) is funded by the German Research Foundation (DFG). T2 - 7th Eurasphalt and Eurobitume Comgress CY - Online meeting DA - 15.06.2021 KW - Bitumen KW - Multiple ageing and rejuvenation KW - Conventional testing KW - DSR KW - BBR KW - FTIR KW - Asphaltene content KW - Column chromatography PY - 2021 SP - 1 EP - 14 AN - OPUS4-53490 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schwettmann, K. A1 - Stephan, D. A1 - Nytus, N. A1 - Radenberg, M. A1 - Weigel, Sandra T1 - Post carbon road - The endless cycle of bitumen reuse N2 - In Germany, the reuse of asphalt has a long tradition. Since the 1980s, the reclaimed asphalt has been recycled achieving a reuse rate of around 90% and thus a very high value in the last years. In the future, instead of the amount, the quality of the reclaimed asphalt will be more important because the recycled asphalt will be reused again and again. Thus, these asphalt mixes are in the second or even third cycle of reuse. Concerning this situation, the question arises if asphalt can be reused several times without any loss in quality. An important factor affecting the asphalt quality is the binder bitumen. During the production, construction and service life, the ageing of this binder occurs causing a hardening of the bitumen. To compensate this hardening, additives for the reclaimed asphalt in terms of rejuvenation agents (rejuvenators) gain in importance. With these rejuvenators, the physical properties of bitumen can be modified e.g. the hardness and the stiffness reduced. However, the mechanism of the rejuvenation agents and the effects of the bitumen chemistry are largely unknown because the composition of the products varies very strongly. But with growing knowledge about these mechanisms and effects of the rejuvenation agents, the chemical composition and thus the physical and ageing behavior of bitumen can be targeted modified by the use of suitable rejuvenators. In this work, the actual results of the project Postcarbone road should be presented including investigations about the chemical and physical mechanisms as well as the efficiency of different rejuvenators. Further, a model for the cyclic reuse of bitumen should be developed. Based on this model, the choice of a suitable rejuvenation agent for the considered bitumen or rather asphalt should be possible. The project Postcarbone road (392670763) is funded by the German Research Foundation (DFG). T2 - 7th Eurasphalt and Eurobitume Congress CY - Online meeting DA - 15.06.2021 KW - Bitumen KW - Multiple ageing and rejuvenation KW - Conventional testing KW - DSR KW - BBR KW - FTIR KW - Asphaltene content KW - Column chromatography PY - 2021 AN - OPUS4-53489 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nöller, Renate A1 - Hahn, Oliver A1 - Danielewski, A. A1 - Giel, R. A1 - Overgaauw, E. T1 - Untersuchungen der Humboldt Codices "Fragmens de peinture hiéroglyphique Aztèques, deposés à la bibliotheque royale de Berlin" N2 - In der Berliner Sammlung "Manuscripta Americana" befinden sich Fragmente von Bilderhandschriften, die Alexander von Humboldt 1804 in Mexiko erwarb und der Königlichen Bibliothek schenkte. Die in der frühen Kolonialzeit hergestellten verschiedenartigen Codices waren damals schon nicht mehr an den Orten ihrer ursprünglichen Verwendung. Entsprechend ihres Seltenheitswertes gelangten einzelne Schriftstücke seit der Conquista in die Bestände bedeutender Persönlichkeiten. Hierzu fertigte man auch Abschriften oder Kopien an, oder zerstückelte sogar einzelne Blätter, so dass die Darstellungen auf den abgetrennten Fragmenten oft nur zum Teil abgebildet vorliegen. Um herauszufinden, ob einige Schriftstücke der "Humboldt Codices" in Bezug zu einander stehen, werden die Dokumente, ihre Symbole und Schriftzeichen und das zur Herstellung verwendete Material miteinander verglichen. Mit den für die Analyse von Manuskripten bewährten Untersuchungsmethoden werden Papier und Farbmittel identifiziert. Hierzu zählen Raman-, FTIR-, Röntgenfluoreszenz- und VIS- Spektroskopie. Charakteristisch für die Herstellung von schriftlichen Dokumenten in der Kolonialzeit von Amerika ist die Verwendung von indigenem Material wie Papier aus Baumrinde und Pflanzenfarben zusammen mit den aus Europa bekannten Materialien. Geklärt wird, inwieweit neben den bekanntesten Farbstoffen wie Cochenille, Mayablau oder Mischungen mit Tonmineralen auch mineralische Pigmente zum Einsatz kamen. Vorgestellt werden die auf Tafel 36 in den "Vues des Cordillères et Monuments des Peuples Indigènes de l`Amerique, Voyage de Humboldt et Bonpland" abgebildeten Fragmente. Die hier von Humboldt vorgenommene Zusammenstellung wird mit der Farbpalette der in Berlin archivierten originalen Schriftstücke verglichen. Die Interpretation der Ergebnisse gibt einen Hinweis auf die Zuordnung oder auch Zusammengehörigkeit dieser einzigartigen Dokumente amerikanischer Geschichte. Hierbei wird die Frage aufgeworfen, inwiefern davon auszugehen ist, dass diese mit weiteren Fragmenten in Verbindung gebracht werden können, was für die Beleuchtung der kulturhistorischen Zusammenhänge von großer Bedeutung ist. T2 - Archäometrie und Denkmalpflege 2018 CY - Hamburg, Germany DA - 20.03.2018 KW - FTIR KW - Humboldt Codices KW - XRF KW - VIS KW - RAMAN PY - 2018 AN - OPUS4-44746 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Noeller, Renate A1 - Danielewski, Angelika A1 - Giel, Robert A1 - Hahn, Oliver A1 - Overgaauw, Everadus T1 - Analysis of the codices `Fragmens de Peinture hiéroglyphique Aztèques, deposés à la Bibliotheque royale de Berlin´ represented on plate 36 in `Vues des Cordillères et Monuments des Peuples Indigènes de l`Amerique, Voyage de Humboldt et Bonpland´ N2 - The mayor part of the Berlin collection `Manuscripta Americana´ consists of documents compiled by Alexander von Humboldt. The diversity of the written fragments and their shape presume few accordance concerning purpose, place or time of production. Even before the papers came to Berlin, manuscripts were copied, divided and collected by famous scholars also in Mexico. Back in Europe, Humboldt visited further collections and published the detected hieroglyphic writings altogether with cultural objects and landscapes in the book `Vues des Cordillères et Monuments des Peuples Indigènes de l`Amerique, voyage de Humboldt et Bonpland´, labelled corresponding to the cultural background. By scientific and culture historical analyses, the Humboldt codices are revised and related to each other and others. In especial, the compilation of fragments shown on plate 36 in the book is looked at more closely. Whereas most of the plates represent only one sheet of painted amate paper, here segments with details of seven fragments are put together. It is tried to comprehend why these pieces are on one plate. To find out a common feature of the documents, their content and represented form are compared. A correlation between some pieces is obvious and thus is also expected in the manufacture of the codices, in the kind of material used. For this the inks and colors are determined by scientific analysis including XRF-, Raman-, FTIR- and VIS- spectroscopy. Special material is detected and related to results of former analysis of codices written during the colonial period of America. Herewith a clear cultural assignment of the manuscripts is performed. A relation of the fragments represented on plate 36 among each other and to other codices of the collection Manuscripta Americana in Berlin is discussed. Also, if the manuscripts are unique `originals´ or represent fragments of documents, whose corresponding pieces maybe found- in the best case- incorporated in other collections. We detected, that at least two of them can be put into relation to similar manuscripts deposited in Mexico. Further material analysis should clarify, if the corresponding pieces are identical- from one document, or if one of them is a copy. Herewith an approximation to authenticity features and history is issued. T2 - 42nd International Symposium on Archaeometry ISA 2018 CY - Merida, Yucatan, Mexico DA - 20.05.2018 KW - Vues des Cordillères KW - VIS KW - Humboldt Codices KW - XRF KW - FTIR KW - Raman PY - 2018 AN - OPUS4-47554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meierhofer, F. A1 - Dissinger, F. A1 - Weigert, Florian A1 - Resch-Genger, Ute A1 - Waldvogel, S. R. A1 - Voss, T. T1 - Citric-Acid-Based Carbon Dots with Luminescence Quantum Yields > 50%: spectral tuning of the luminescence by ligand exchange and pH adjustment N2 - We report the synthesis and characterization of carbon nanodots (CDs) with high quantum yield (>50%) and tailored optical absorption as well as emission properties. A well-described protocol with polyethyleneimine (PEI) as amine precursor is used as a reference to a new CD system which is stabilized by aromatic 2,3-diaminopyridine (DAP) molecules instead. The DAP stabilizer is installed in order to red-shift the absorption peak of the n-π* electron transition allowing efficient radiative recombination and light emission. Size, shape, and chemical composition of the samples are determined by (HR)TEM, EDX and FTIR-spectroscopy. Optical parameters are investigated using UV-VIS, PL and QY measurements. Several parameters such as concentration, excitation wavelength and pH are studied. Zeta-potential analysis indicate that pH-induced (de-)protonation processes of functional moieties directly affect the n-π* energy bands. This results in unique pH-dependent absorption and emission characteristics which are discussed on the specific chemical composition of each CD system. T2 - MRS 2019 CY - Boston, MA, USA DA - 03.12.2019 KW - Nanoparticle KW - Carbon dot KW - Surface chemistry KW - Fluorescence KW - PH KW - Ligand KW - FTIR KW - Synthesis KW - Characterization PY - 2019 AN - OPUS4-49968 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg A1 - Bär, Sylke A1 - Jaunich, Matthias A1 - Wolff, Dietmar A1 - Puskar, L. A1 - Schade, U. T1 - Photolytically and Thermally Initiated Destruction N2 - Casks for storage and transportation of used fuel rods of radioactive material are equipped with polyethylene (PE) for improved neutron flux shielding. The embedded PE structures are additionally exposed to gamma radiation and heat flow due to the specific high activity of the fission products. 60Co γ-radiation and heat load experiments at 125°C has been performed to evaluate PE degradation during the ageing process. FAR-FTIR-experiments were subsequently performed at differently aged PE test samples to characterize the oxidation process and morphological changes in the samples during the ageing at 125°C. T2 - 11'th Joint BER II and BESSY II User Meeting CY - Berlin, Germany DA - 04.12.2019 KW - FTIR KW - High Molecular Polyethylene KW - Ageing PY - 2019 AN - OPUS4-49988 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -