TY - GEN A1 - Friedrich, C. M. A1 - Weigel, S. A1 - Marvin, H. A1 - Rauscher, H. A1 - Wohlleben, W. A1 - Babick, F. A1 - Löschner, K. A1 - Mech, A. A1 - Brüngel, R. A1 - Hodoroaba, Vasile-Dan A1 - Gilliland, D. A1 - Rasmussen, K. A1 - Ghanem, A. T1 - The NanoDefine Methods Manual N2 - This document is a collection of three JRC Technical Reports that together form the “NanoDefine Methods Manual”, which has been developed within the NanoDefine project ‘Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial’, funded by the European Union’s 7th Framework Programme, under grant agreement 604347. The overall goal of the NanoDefine project was to support the implementation of the European Commission Recommendation on the definition of nanomaterial (2011/696/EU). The project has developed an integrated empirical approach, which allows identifying a material as a nano- or not a nanomaterial according to the EC Recommendation. The NanoDefine Methods Manual consists of three parts: Part 1: The NanoDefiner Framework and Tools, which covers the NanoDefiner framework, general information on measurement methods and performance criteria, and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2: Evaluation of Methods, which discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3: Standard Operating Procedures (SOPs), which presents the 23 Standard Operating Procedures developed within the NanoDefine project. In this combined document, these three parts are included as stand-alone reports, each having its own abstract, table of contents, page, table and figure numbering, and references. KW - Nanomaterial KW - Particle size distribution KW - Nanoparticles KW - NanoDefine KW - Nanomaterial classification PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504250 SN - 978-92-76-12335-4 DO - https://doi.org/10.2760/79490 VL - JRC117501 SP - 1 EP - 451 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mech, A. A1 - Rauscher, H. A1 - Rasmussen, K. A1 - Babick, F. A1 - Hodoroaba, Vasile-Dan A1 - Ghanem, A. A1 - Wohlleben, W. A1 - Marvin, H. A1 - Brüngel, R. A1 - Friedrich, C. M. A1 - Löschner, K. A1 - Gilliland, D. T1 - The NanoDefine Methods Manual - Part 3: Standard Operating Procedures (SOPs) N2 - The present series of reports, the NanoDefine Methods Manual, has been developed within the NanoDefine project 'Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial'1 funded by the European Union's 7th Framework Programme, under grant agreement 604347. In 2011 the European Commission (EC) published the recommendation (2011/696/EU) for a definition of the term 'nanomaterial'1, the EC NM Definition, as a reference to determine whether an unknown material can be considered as a 'nanomaterial' for regulatory purposes. One challenge is the development of methods that reliably identify, characterize and quantify nanomaterials (NM) both as substances and in various products and matrices. The overall goal of NanoDefine was to support the implementation of the EC NM Definition. It can also support the implementation of any NM definition based on particle size. The project has developed an integrated approach, which allows identifying any material as a nano or non-nano material according to the EC NM Definition. NanoDefine explicitly supported the governance challenges associated with the implementation of legislation concerning nanomaterials by: - addressing the issues on availability of suitable measuring techniques, reference materials, validated methods, acceptable to all - developing an integrated and interdisciplinary approach and a close international co-operation and networking with academia, commercial firms and standardization bodies. Thus, the NanoDefine Methods Manual provides guidance on practical implementation of the EC NM Definition throughout the nanomaterial characterization process, and on the characterization techniques employed as well as their application range and limits. It assists the user in choosing the most appropriate measurement method(s) to identify any substance or mixture for a specific purpose, according to the EC NM Definition of a nanomaterial. The NanoDefine project also explored how to assess a material against the criteria of the definition through proxy solutions, i.e. by applying measurement techniques that indirectly determine the D50. Those findings were developed through empirically based scientific work and are included in Part 1 of this Manual. As they go beyond the text of the EC NM Definition, they may be used as practical approach to indicate whether a material is a nanomaterial or not, but keeping in mind that they should not be taken as recommendation for the implementation of the EC NM Definition in a regulatory context. The NanoDefine Methods Manual consists of the following three parts:  Part 1: The NanoDefiner Framework and Tools  Part 2: Evaluation of Methods  Part 3: Standard Operating Procedures (SOPs) Part 1 covers the NanoDefiner framework, general information on measurement methods and performance criteria and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2 discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3 presents the 23 Standard Operating Procedures developed within the NanoDefine project. The current document is part 3. KW - Nanomaterial KW - Nanoparticles KW - Particle size distribution KW - NanoDefine KW - Standard Operation Procedures KW - Nanomaterial classification KW - SOP PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503710 SN - 978-92-76-11955-5 DO - https://doi.org/10.2760/02910 SN - 1831-9424 VL - JRC117501 SP - 1 EP - 215 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50371 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bachmann, H. J. A1 - Bucheli, T. D. A1 - Dieguez-Alonso, A. A1 - Fabbri, D. A1 - Knicker, H. A1 - Schmidt, H.-P. A1 - Ulbricht, A. A1 - Becker, Roland A1 - Buscaroli, A. A1 - Buerge, D. A1 - Cross, A. A1 - Dickinson, D. A1 - Enders, A. A1 - Esteves, V.I. A1 - Evangelou, M. W. H. A1 - Fellet, G. A1 - Friedrich, K. A1 - Gasco Guerrero, G. A1 - Glaser, B. A1 - Hanke, U. M. A1 - Hanley, K. A1 - Hilber, I. A1 - Kalderis, D. A1 - Leifeld, J. A1 - Masek, O. A1 - Mumme, J. A1 - Paneque Carmona, M. A1 - Calvelo Pereira, R. A1 - Rees, F. A1 - Rombola, A. G. A1 - de la Rosa, J. M. A1 - Sakrabani, R. A1 - Sohi, S. A1 - Soja, G. A1 - Valagussa, M. A1 - Verheijen, F. A1 - Zehetner, F. T1 - Towards the standardization of biochar analysis: the COST action TD1107 interlaboratory comparison N2 - Biochar produced by pyrolysis of organic residues is increasingly used for soil amendment and many other applications. However, analytical methods for its physical and chemical characterization are yet far from being specifically adapted, optimized, and standardized. Therefore, COST Action TD1107 conducted an interlaboratory comparison in which 22 laboratories from 12 countries analyzed three different types of biochar for 38 physical–chemical parameters (macro- and microelements, heavy metals, polycyclic aromatic hydrocarbons, pH, electrical conductivity, and specific surface area) with their preferential methods. The data were evaluated in detail using professional interlaboratory testing software. Whereas intralaboratory repeatability was generally good or at least acceptable, interlaboratory reproducibility was mostly not (20% < mean reproducibility standard deviation < 460%). This paper contributes to better comparability of biochar data published already and provides recommendations to improve and harmonize specific methods for biochar analysis in the future. KW - Biochar KW - Analysis KW - Standardization KW - Ring test KW - Interlaboratory comparison PY - 2016 DO - https://doi.org/10.1021/acs.jafc.5b05055 SN - 0021-8561 SN - 1520-5118 VL - 64 IS - 2 SP - 513 EP - 527 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-35289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lippitz, Andreas A1 - Koprinarov, Ivaylo A1 - Friedrich, Jörg Florian A1 - Unger, Wolfgang A1 - Weiss, K. A1 - Wöll, Ch. T1 - Surface analysis of metaillized poly(bisphenol A cabonate) films by x-ray absorption spectroscopy (NEXAFS) KW - NEXAFS KW - Röntgenadsorptionsspektroskopie KW - Oberflächenanalyse KW - Film, metallisiert KW - Polymeroberfläche PY - 1996 SN - 0032-3861 SN - 1873-2291 VL - 37 IS - 14 SP - 3157 EP - 3160 PB - Springer CY - Berlin AN - OPUS4-649 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Theiler, Geraldine A1 - Hübner, Wolfgang A1 - Gradt, Thomas A1 - Klein, P. A1 - Friedrich, K. T1 - Friction and wear of PTFE composites at cryogenic temperatures N2 - This paper presents investigations on the tribological behaviour of PTFE composites against steel at cryogenic temperatures. The results showed that the friction coefficient decreases with temperature down to 77 K, but did not follow a linear evolution further down to extreme low temperatures. It can be stated that the cryogenic environment has a significant influence on the tribological performance of the polymer composites. The effect of low temperatures was more clearly detected at low sliding speed, where friction heat is reduced. A change in wear mechanism from adhesive to abrasive was observed in this case. SEM and AFM analyses showed that the PTFE matrix composites investigated under these experimental conditions have transferred material onto the disc down to very low temperatures. Chemical analyses indicate the presence of iron fluorides. KW - PTFE composites KW - Cryogenic tribology KW - Transfer film PY - 2002 DO - https://doi.org/10.1016/S0301-679X(02)00035-X SN - 0301-679X VL - 35 IS - 7 SP - 449 EP - 458 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-1866 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Klein, P. A1 - Zhang, Z. A1 - Friedrich, K. A1 - Theiler, Geraldine A1 - Hübner, Wolfgang T1 - Zur Bildung von Transferfilmen bei ausgewählten PTFE-Compounds T2 - Tribologie-Fachtagung 2002 CY - Göttingen, Deutschland DA - 2002-09-23 PY - 2002 SN - 3-00-003404-8 VL - 1 SP - 8-1-8-11 PB - GfT CY - Moers AN - OPUS4-1867 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Theiler, Geraldine A1 - Hübner, Wolfgang A1 - Klein, P. A1 - Friedrich, K. T1 - Tribologisches Verhalten der Werkstoffpaarung Polymerverbundwerkstoff/Stahl bei tiefen Temperaturen T2 - 44. Tribologie-Fachtagung CY - Göttingen, Deutschland DA - 2003-09-22 PY - 2003 SN - 3-00-003404-8 VL - 1 SP - 8-1-8-12 PB - GfT CY - Moers AN - OPUS4-2664 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klein, P. A1 - Friedrich, K. A1 - Theiler, Geraldine A1 - Hübner, Wolfgang T1 - Mechanische und tribologische Eigenschaften von PTFE/PEEK/CF-Verbundwerkstoffen T2 - BAM-Sonderheft 2003 "Polymere Verbundwerkstoffe zwischen Raumtemperatur und 4,2 K" ; 2. Symposium im DFG-Projekt: Eigenschaften von PTFE- und PEEK-Matrix-Werkstoffen bei tribologischer Beanspruchung CY - Berlin, Deutschland DA - 2003-02-27 PY - 2003 SP - 11 EP - 17 AN - OPUS4-2669 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine A1 - Hübner, Wolfgang A1 - Klein, P. A1 - Friedrich, K. T1 - Oberflächencharakterisierung von Paarungen PTFE-Komposit/Stahl nach tribologischer Beanspruchung in LN2, LH2 und LHe - Rolle der Kältemittel T2 - BAM-Sonderheft 2003 "Polymere Verbundwerkstoffe zwischen Raumtemperatur und 4,2 K" ; 2. Symposium im DFG-Projekt: Eigenschaften von PTFE- und PEEK-Matrix-Werkstoffen bei tribologischer Beanspruchung CY - Berlin, Deutschland DA - 2003-02-27 PY - 2003 SP - 17 EP - 23 AN - OPUS4-2670 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Grytsenko, K. P. A1 - Capobianchi, A. A1 - Convertino, A. A1 - Friedrich, Jörg Florian A1 - Schulze, Rolf-Dieter A1 - Ksensov, V. A1 - Schrader, S. ED - Iwamori, S. T1 - Polymer-metal nanocomposite thin film prepared by co-evaporation in a vacuum PY - 2005 SN - 81-7736276-3 SP - 85 EP - 109 PB - Research Signpost CY - Trivandrum, Kerala AN - OPUS4-11225 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Unger, Wolfgang A1 - Lippitz, Andreas A1 - Friedrich, Jörg Florian A1 - Koprinarov, Ivaylo A1 - Weiss, K. A1 - Wöll, Ch. ED - Mittal, K. T1 - The Application of Near Edge X-ray Absorption Fine Structures (NEXAFS) Spectroscopy and X-ray Photoelectron Spectroscopy (XPS) in Surface Analysis of Chromium-evaporated Polymers and Organic Films PY - 1998 SN - 90-6764-290-8 SP - 147 EP - 168 PB - VSP CY - Utrecht AN - OPUS4-6986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Grytsenko, K. A1 - Grynko, D. A1 - Lozovski, V. A1 - Friedrich, Jörg Florian A1 - Schulze, Rolf-Dieter A1 - Jurga, J. A1 - Convertino, A. A1 - Kotko, A. ED - Jurga, J. T1 - Properties of Au nano-clusters in PTFE film prepared by co-evaporation in a vacuum PY - 2004 SN - 83-7143-232-1 SP - 79 EP - 84 PB - Wydawn. Politechniki Pozna´nskiej CY - Poznan AN - OPUS4-6961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mach, Reinhard A1 - Letzig, U. A1 - Goering, Harald A1 - Oleszak, Franz A1 - Friedrich, Jörg Florian A1 - Richter, K. T1 - Effects of Heat Treatment on the Structure of Thermal Plasma Synthesized SiCN Composite Nanopowders N2 - SiCN composite nanopowders with different chemical composition and characteristics were synthesized by the RF induction plasma at atmospheric pressure. Frequently the as-produced powders exhibit a high degree of chemical disorder or structural defects. Because the composition and the microstructure of starting powders have a great influence on the properties of composite ceramics, the changes of chemical composition, crystallization, and morphology of the as-produced powders during heat treatment up to 1500 °C were investigated in detail. PY - 2003 UR - http://www.ipme.ru/e-journals/RAMS/no_1503/tai/tai.html SN - 1606-5131 VL - 5 IS - 1 SP - 85 EP - 90 PB - Advanced Study Center CY - St. Petersburg AN - OPUS4-6968 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zeynalov, Eldar A1 - Maherramova, S.N. A1 - Sadieva, N.F. A1 - Iskenderova, S.A. A1 - Agayev, B. K. A1 - Friedrich, Jörg Florian T1 - New softeners for polyvinylchloride N2 - Die Produktion von neuen effektiven und 'grünen' Weichmachern für Polyvinylchlorid (PVC) stellt eine der großen Herausforderungen in der chemischen Industrie dar. In diesem Beitrag wird über Ergebnisse von Untersuchungen berichtet, in denen symmetrische Ester einer Reihe von Fettsäuren und Triethylenglykol (TEG) gewonnen wurden und die als effektive Plastifizierungskomponenten verwendet wurden. Die Veresterung wurde unter Zugabe von Titandioxid Degussa P-25 in Nanopartikelgröße als umweltverträgliche Technologie durchgeführt. Eine gute Verträglichkeit und eine niedrige Flüchtigkeit der Ester auf Biobasis in den PVC-Rezepturen werden gezeigt und es konnten bessere physiko-mechanische Eigenschaften der PVC-Komposite eingestellt werden. Die Ester können als effektive und umweltfreundliche PVC-Weichmacher und als Ersatz für herkömmliche Phtalate empfohlen werden. KW - Softener KW - Polyvinylchloride PY - 2012 SN - 0025-5300 VL - 54 IS - 4 SP - 246 EP - 248 PB - Hanser CY - München AN - OPUS4-25747 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Debatin, F. A1 - Behrens, K. A1 - Weber, J. A1 - Baburin, I. A. A1 - Thomas, A. A1 - Schmidt, J. A1 - Senkovska, I. A1 - Kaskel, S. A1 - Kelling, A. A1 - Hedin, N. A1 - Bacsik, Z. A1 - Leoni, S. A1 - Seifert, G. A1 - Jäger, Christian A1 - Günter, C. A1 - Schilde, U. A1 - Friedrich, A. A1 - Holdt, H.-J. T1 - An isoreticular family of microporous metal-organic frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate: syntheses, structures and properties N2 - We report on a new series of isoreticular frameworks based on zinc and 2-substituted imidazolate-4-amide-5-imidate (IFP-1–4, IFP=imidazolate framework Potsdam) that form one-dimensional, microporous hexagonal channels. Varying R in the 2-substitued linker (R=Me (IFP-1), Cl (IFP-2), Br (IFP-3), Et (IFP-4)) allowed the channel diameter (4.0–1.7 Å), the polarisability and functionality of the channel walls to be tuned. Frameworks IFP-2, IFP-3 and IFP-4 are isostructural to previously reported IFP-1. The structures of IFP-2 and IFP-3 were solved by X-ray crystallographic analyses. The structure of IFP-4 was determined by a combination of PXRD and structure modelling and was confirmed by IR spectroscopy and 1H MAS and 13C CP-MAS NMR spectroscopy. All IFPs showed high thermal stability (345–400°C); IFP-1 and IFP-4 were stable in boiling water for 7 d. A detailed porosity analysis was performed on the basis of adsorption measurements by using various gases. The potential of the materials to undergo specific interactions with CO2 was investigated by measuring the isosteric heats of adsorption. The capacity to adsorb CH4 (at 298 K), CO2 (at 298 K) and H2 (at 77 K) at high pressure were also investigated. In situ IR spectroscopy showed that CO2 is physisorbed on IFP-1–4 under dry conditions and that both CO2 and H2O are physisorbed on IFP-1 under moist conditions. KW - Adsorption KW - Metal-organic frameworks KW - Microporous materials KW - N,O ligands KW - Zinc PY - 2012 DO - https://doi.org/10.1002/chem.201200889 SN - 0947-6539 SN - 1521-3765 VL - 18 IS - 37 SP - 11630 EP - 11640 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-27725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Theiler, Géraldine A1 - Hübner, Wolfgang A1 - Gradt, Thomas A1 - Klein, P. A1 - Friedrich, K. T1 - Tribologisches Verhalten der Werkstoffpaarung Polymerverbundwerkstoff/Stahl bei tiefen Temperaturen KW - Kryotechnik KW - Polymerkomposite KW - PTFE KW - PEEK KW - Flüssigwasserstoff KW - Flüssighelium KW - Reibungszahlen KW - Übertrag PY - 2005 SN - 0724-3472 VL - 52 IS - 1 SP - 20 EP - 25 PB - Expert Verlag CY - Renningen AN - OPUS4-12645 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine A1 - Hübner, Wolfgang A1 - Klein, P. A1 - Friedrich, K. ED - Bageur, G. G. ED - Seyfert, P. T1 - Influence of low temperatures and environmental media on the frictional characteristics of PTFE composites T2 - ICEC 19 - 19th International Cryogenic Engineering Conference CY - Grenoble, France DA - 2002-07-22 PY - 2002 SN - 81-7319508-0 SP - 717 EP - 720 PB - Narosa Publ. House CY - New Delhi AN - OPUS4-12661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine A1 - Meine, Kerstin A1 - Hübner, Wolfgang A1 - Klein, P. A1 - Friedrich, K. ED - Bageur, G. G. ED - Seyfert, P. T1 - Thermal shock cycle experiments between room and cryogenic temperatures on polymer composites T2 - ICEC 19 - 19th International Cryogenic Engineering Conference CY - Grenoble, France DA - 2002-07-22 PY - 2002 SN - 81-7319508-0 SP - 729 EP - 732 PB - Narosa Publ. House CY - New Delhi AN - OPUS4-12662 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Klein, P. A1 - Zhang, Z. A1 - Friedrich, K. A1 - Theiler, Géraldine A1 - Hübner, Wolfgang T1 - Zur Bildung von Transferfilmen bei ausgewählten PTFE-Compounds KW - Wear KW - Transfer film KW - Polytetrafluoroethylene KW - Composites PY - 2003 SN - 0724-3472 VL - 50 IS - 4 SP - 32 EP - 36 PB - Expert Verlag CY - Renningen AN - OPUS4-12663 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hübner, Wolfgang A1 - Theiler, Geraldine A1 - Klein, P. A1 - Friedrich, K. T1 - Untersuchungen zum Einfluss kryogener Medien auf den Materialtransfer im Tribosystem Polymer-Komposit/Stahl T2 - Tribologie-Fachtagung 2000 CY - Göttingen, Deutschland DA - 2000-09-25 PY - 2000 SN - 3-00-003404-8 VL - 1 SP - 12-1 - 12-11 PB - Gesellschaft für Tribologie CY - Moers AN - OPUS4-12654 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klein, P. A1 - Friedrich, K. A1 - Theiler, Geraldine A1 - Hübner, Wolfgang T1 - Tribologische Untersuchungen an PTFE-Verbundwerkstoffen für den Einsatz in kryogenen Medien T2 - Tribologie-Fachtagung 2000 CY - Göttingen, Deutschland DA - 2000-09-25 PY - 2000 SN - 3-00-003404-8 VL - 1 SP - 9-1 - 9-10 PB - Gesellschaft für Tribologie CY - Moers AN - OPUS4-12655 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Theiler, Geraldine A1 - Hübner, Wolfgang A1 - Klein, P. A1 - Friedrich, K. ED - Friedrich, K. ED - Hübner, W. T1 - Tribologische Eigenschaften ausgewählter PTFE-Werkstoffe bei tiefen Temperaturen T2 - 1. Symposium im DFG-Projekt 'Eigenschaften von PTFE- und PEEK-Matrix-Werkstoffen bei Tribologischer Beanspruchung' CY - Berlin, Germany DA - 2000-11-24 PY - 2001 N1 - Serientitel: BAM-Sonderheft – Series title: BAM-Sonderheft IS - 3 SP - 19 EP - 26 PB - BAM CY - Berlin AN - OPUS4-12656 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klein, P. A1 - Friedrich, K. A1 - Theiler, Geraldine A1 - Hübner, Wolfgang ED - Friedrich, K. ED - Hübner, W. T1 - Untersuchungen zum Verschleissverhalten ausgewählter PTPE-Werkstoffe bei Raumtemperatur T2 - 1. Symposium im DFG-Projekt 'Eigenschaften von PTFE- und PEEK-Matrix-Werkstoffen bei Tribologischer Beanspruchung' CY - Berlin, Germany DA - 2000-11-24 PY - 2001 N1 - Serientitel: BAM-Sonderheft – Series title: BAM-Sonderheft VL - 2001-3 IS - 3 SP - 13 EP - 18 PB - BAM CY - Berlin AN - OPUS4-12657 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hübner, Wolfgang A1 - Theiler, Geraldine A1 - Gradt, Thomas A1 - Klein, P. A1 - Friedrich, K. T1 - Der Einfluss kryogener Medien auf den Materialtransfer im Tribosystem Polymerkomposit/Stahl PY - 2001 SN - 0724-3472 VL - 48 IS - 6 SP - 8 EP - 12 PB - Expert Verlag CY - Renningen AN - OPUS4-12659 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Hübner, Wolfgang A1 - Theiler, Geraldine A1 - Klein, P. A1 - Friedrich, K. T1 - Tribological behaviour of PTFE composites against steel at cryogenic temperatures T2 - 2nd World Tribology Congress ; 2nd WTC 2001 CY - Vienna, Austria DA - 2001-09-03 KW - PTFE composite KW - Cryogenic temperature KW - Transfer film KW - SEM KW - XPS PY - 2001 SN - 3-901657-09-6 SP - 1(?) EP - 4(?) PB - ÖTG CY - Vienna AN - OPUS4-12660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, K. A1 - Klein, P. A1 - Theiler, Geraldine A1 - Ye, L. A1 - Mai, Y.W. T1 - PEEK- and PTFE- Based Composites for Tribology Applications in a Range between Liquid Helium and Room Temperature N2 - This study deals with the development of PEEK (polyehteretherketone) and PTFE (polytetrafluoroethylene) based composites, optimized for low friction and low wear performance under extreme environments. It is demonstrated that the incorporation of a harder polymer component into PTFE (such as PEEK particles), a short fiber reinforcement (e.g. carbon fibers CF), and internal lubricants (e.g. PTFE particles), helps to reduce the friction and to improve the wear resistance over a very wide temperature range. KW - Composites KW - Tribology KW - PEEK KW - PTFE KW - Temperature KW - Friction KW - Wear PY - 2007 SN - 1013-9826 VL - 334-335 SP - 597 EP - 600 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-15045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hirschberg, L. A1 - Bake, Friedrich A1 - Knobloch, K. A1 - Hulshoff, S. A1 - Hirschberg, A. T1 - Experimental investigations of indirect noise due to modulation of axial vorticity and entropy upstream of a choked nozzle N2 - An experimental cold-gas study of the response of a choked convergent–divergent nozzle to swirl perturbations is presented. The perturbations were obtained by means of upstream unsteady tangential injections into initially steady flows with different values of steady background swirl. The swirl perturbations induced changes in the axial mass-flow rate, due to either their ingestion or evacuation by the nozzle. This in turn caused a downstream acoustic response. For low-intensity background swirl the responses were found to be similar to those obtained without steady background swirl. Perturbations of a high-intensity background swirl led to different effects. For long injection times, the negative mass-flow rate modulation occurred in two stages. The first stage was similar to that of the background-swirl free case. The second stage occurred after a short time delay, and induced a much stronger negative acoustic response. This unexpected behavior suggests that a significant part of the tangentially injected fluid flows upstream inducing an accumulation of swirl, which is – after tangential injection is ceased – suddenly cleared out through the nozzle. A scaling rule for the amplitudes of these acoustic responses is reported. Furthermore, quasi-steady models, based on steady-state measurements are proposed. These models predict the downstream acoustic response amplitude within a factor two. Additionally, preliminary empirical evidence of the effect of swirl on the downstream acoustic response due to the interaction of entropy patches with a choked nozzle is reported. This was obtained by comparison of sound produced by abrupt radial or tangential sonic injection, upstream from the choked nozzle, of air from a reservoir at room temperature to that from a reservoir with a higher stagnation temperature. Because the mass flow through the nozzle does not increase instantaneously, the injected higher-enthalpy air accumulates upstream of the injection-port position in the main flow. This eventually induces a large downstream acoustic pulse when tangential injection is interrupted. The magnitude of the resulting sound pulse can reach that of a quasi-steady response of the nozzle to a large air patch with a uniform stagnation temperature equal to that of the upstream-injected heated air. This hypothesis is consistent with the fact that the initial indirect-sound pulse is identical to one obtained with unheated air injection. The authors posit that – given all of the insight gleaned from them in this case – acoustic measurements of indirect sound appear to be a potentially useful diagnostic tool. KW - Aeroacoustics KW - Indirect combustion noise KW - Vorticity noise KW - Entropy noise KW - Swirl PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-548331 DO - https://doi.org/10.1016/j.jsv.2022.116989 SN - 0022-460X VL - 532 SP - 1 EP - 22 PB - Elsevier Ltd. AN - OPUS4-54833 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Friedrich, K. A1 - Klein, P. A1 - Theiler, Geraldine A1 - Ye, L. A1 - Mai, Y. W. T1 - PTFE-based composites for Tribology apllications in a range between liquid helium and room temperature T2 - 5. Asian-Australasian Conference on Composite Materials (ACCM-5) CY - Hong Kong, China DA - 2006-11-27 PY - 2006 AN - OPUS4-30883 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grytsenko, K. P. A1 - Kolomzarov, Y. A1 - Lytvyn, O. A1 - Strelchuk, V. A1 - Ksianzou, V. A1 - Schrader, S. A1 - Beyer, H. A1 - Servet, B. A1 - Enouz-Vedrenne, S. A1 - Garry, G. A1 - Schulze, Rolf-Dieter A1 - Friedrich, Jörg Florian T1 - Metal-filled polytetrafluoroethylene nanostructered thin film N2 - Thin metal-filled polyterafluoroethylene films with various metal concentration were produced by co-deposition in vacuum. Metal nanocluster size increased with metal concentration. Films were heated up to 300 degrees C, their optical spectra were recorded during heating. The changes in plasmon band shape and wavelength of the nanocluster ensemble during heating are not linearly related with metal concentration and heating temperature. This is caused by different thermal behavior of the complex processes, which are taking place in each of the two materials present in the film. The metal cluster size and optical properties of the whole ensemble can be purposefully formed by varying metal nature, its concentration and annealing temperature of the film. Nano- and micro-domains with properties different from original film were generated by focused excimer laser or electron beam. Gold-filled PTFE nano-structured films were used as substrate for surface enhanced Raman scattering measurements of ultrathin film of Rhodamine 6G dye. KW - Gold nanoparticles KW - Arrays KW - SERS PY - 2010 UR - http://openurl.ingenta.com/content?genre=article&issn=1936-6612&volume=3&issue=3&spage=308&epage=312 DO - https://doi.org/10.1166/asl.2010.1127 SN - 1936-6612 SN - 1936-7317 VL - 3 IS - 3 SP - 308 EP - 312 PB - American Scientific Publ. CY - Stevenson Ranch, Calif. AN - OPUS4-23957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Friedrich, K. A1 - Theiler, Geraldine A1 - Klein, P. ED - Sujeet K. Sinha, ED - Brian J. Briscoe, T1 - Polymer composites for tribological applications in a range between liquid Helium and room temperature KW - Polymer composites KW - Tribology PY - 2009 SN - 978-1-84816-202-0 IS - Chapter 11 SP - 375 EP - 415 PB - Imperial College Press AN - OPUS4-19517 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Klein, P. A1 - Theiler, Geraldine A1 - Friedrich, K. T1 - Tribological behavior of short Carbon fiber reinforced PTFE- and PEEK-compounds T2 - 15th International Sealing Conference CY - Stuttgart, Germany DA - 2008-10-07 KW - Polymer composite KW - Tribology KW - Low temperatures PY - 2008 SN - 978-3-00-025884-8 IS - A 22 SP - 292 EP - 301 PB - Leithner Media Production CY - Ebelsbach AN - OPUS4-19518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lukowiak, M.C. A1 - Wettmarshausen, Sascha A1 - Hidde, Gundula A1 - Landsberger, Petra A1 - Boenke, Viola A1 - Rodenacker, K. A1 - Braun, Ulrike A1 - Friedrich, Jörg Florian A1 - Gorbushina, Anna A1 - Haag, R. T1 - Polyglycerol coated polypropylene surfaces for protein and bacteria resistance N2 - Polyglycerol (PG) coated polypropylene (PP) films were synthesized in a two-step approach that involved plasma bromination and subsequently grafting hyperbranched polyglycerols with very few amino functionalities. The influence of different molecular weights and density of reactive linkers were investigated for the grafted PGs. Longer bromination times and higher amounts of linkers on the surface afforded long-term stability. The protein adsorption and bacteria attachment of the PP-PG films were studied. Their extremely low amine content proved to be beneficial for preventing bacteria attachment. PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-325406 DO - https://doi.org/10.1039/c4py01375a SN - 1759-9954 SN - 1759-9962 VL - 6 IS - 8 SP - 1350 EP - 1359 AN - OPUS4-32540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mech, A. A1 - Wohlleben, W. A1 - Ghanem, A. A1 - Hodoroaba, Vasile-Dan A1 - Weigel, S. A1 - Babick, F. A1 - Brüngel, R. A1 - Friedrich, C. M. A1 - Rasmussen, K. A1 - Rauscher, H. T1 - Nano or Not Nano? A Structured Approach for Identifying Nanomaterials According to the European Commission’s Definition N2 - Identifying nanomaterials (NMs) according to European Union Legislation is challenging, as there is an enormous variety of materials, with different physico-chemical properties. The NanoDefiner Framework and its Decision Support Flow Scheme (DSFS) allow choosing the optimal method to measure the particle size distribution by matching the material properties and the performance of the particular measurement techniques. The DSFS leads to a reliable and economic decision whether a material is an NM or not based on scientific criteria and respecting regulatory requirements. The DSFS starts beyond regulatory requirements by identifying non-NMs by a proxy Approach based on their volume-specific surface area. In a second step, it identifies NMs. The DSFS is tested on real-world materials and is implemented in an e-tool. The DSFS is compared with a decision flowchart of the European Commission’s (EC) Joint Research Centre (JRC), which rigorously follows the explicit criteria of the EC NM definition with the focus on identifying NMs, and non-NMs are identified by exclusion. The two approaches build on the same scientific basis and measurement methods, but start from opposite ends: the JRC Flowchart starts by identifying NMs, whereas the NanoDefiner Framework first identifies non-NMs. KW - Classification KW - Definition KW - Identification KW - Nanomaterials KW - Particle size KW - Regulation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-510917 DO - https://doi.org/10.1002/smll.202002228 SN - 1613-6829 SP - 2002228-1 EP - 2002228-16 PB - Wiley-VCH CY - Weinheim AN - OPUS4-51091 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mech, A. A1 - Rauscher, H. A1 - Rasmussen, K. A1 - Babick, F. A1 - Hodoroaba, Vasile-Dan A1 - Ghanem, A. A1 - Wohlleben, W. A1 - Marvin, H. A1 - Brüngel, R. A1 - Friedrich, C. M. T1 - The NanoDefine Methods Manual - Part 2: Evaluation of methods N2 - The present series of reports, the NanoDefine Methods Manual, has been developed within the NanoDefine project 'Development of an integrated approach based on validated and standardized methods to support the implementation of the EC recommendation for a definition of nanomaterial', funded by the European Union's 7th Framework Programme, under grant agreement 604347. In 2011 the European Commission (EC) published a recommendation for a definition of the term 'nanomaterial', the EC NM Definition, as a reference to determine whether an unknown material can be considered as a 'nanomaterial' for regulatory purposes1. One challenge is the development of methods that reliably identify, characterize and quantify nanomaterials (NM) both as substances and in various products and matrices. The overall goal of NanoDefine was to support the implementation of the EC NM Definition. It can also support the implementation of any NM definition based on particle size. The project has developed an integrated approach, which allows identifying any material as a nano- or not a nanomaterial according to the EC NM Definition. NanoDefine explicitly supported the governance challenges associated with the implementation of legislation concerning nanomaterials by: - addressing the issues on availability of suitable measuring techniques, reference materials, validated methods, acceptable to all stakeholders (authorities, policy makers, commercial firms), - developing an integrated and interdisciplinary approach and a close international co-operation and networking with academia, commercial firms and standardization bodies. Thus, the NanoDefine Methods Manual provides guidance on practical implementation of the EC NM Definition throughout the nanomaterial characterization process, and on the characterization techniques employed as well as their application range and limits. It assists the user in choosing the most appropriate measurement method(s) to identify any substance or mixture for a specific purpose, according to the EC NM Definition of a nanomaterial. The NanoDefine project also explored how to assess a material against the criteria of the definition through proxy solutions, i.e. by applying measurement techniques that indirectly determine the x50. Those findings were developed through empirically based scientific work and are included in Part 1 of this Manual. As they go beyond the text of the EC NM Definition, they may be used as practical approach to indicate whether a material is a nanomaterial or not, but keeping in mind that they should not be taken as recommendation for the implementation of the EC NM Definition in a regulatory context. The NanoDefine Methods Manual consists of the following three parts:  Part 1: The NanoDefiner Framework and Tools  Part 2: Evaluation of Methods  Part 3: Standard Operating Procedures (SOPs) Part 1 covers the NanoDefiner framework, general information on measurement methods and performance criteria and tools developed by NanoDefine such as a materials categorisation system, a decision support flow scheme and an e-tool. Part 2 discusses the outcome of the evaluation of the nanomaterials characterisation methods for measuring size. Part 3 presents the 23 Standard Operating Procedures developed within the NanoDefine project. The current document is part 2. KW - Nanomaterial KW - Nanoparticles KW - NanoDefine KW - Particle size distribution KW - Nanomaterial classification PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-503708 SN - 978-92-76-11953-1 DO - https://doi.org/10.2760/071877 SN - 1831-9424 VL - JRC117501 SP - 1 EP - 133 PB - Publications Office of the European Union CY - Luxembourg AN - OPUS4-50370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Friedrich, K. A1 - Theiler, Geraldine A1 - Klein, P. ED - Sinha, S. K. T1 - Chapter 9: Polymer composites for tribological applications in a range between liquid helium and room temperature N2 - This chapter deals with the development of polyetheretherketone (PEEK) and polytetrafluoroethylene (PTFE)-based composites, optimized for low friction and low wear performance under extreme environments. It is demonstrated that the incorporation of a harder polymer component into PTFE (such as PEEK particles), a short fiber reinforcement (e.g. carbon fibers (CFs)) and internal lubricants (e.g. PTFE particles) helps to reduce the friction and to improve the wear resistance over a very wide temperature range. KW - Polymer composites KW - Friction KW - Wear KW - Cryogenic temperature PY - 2018 SN - 978-981-3227-78-1 SN - 978-981-3227-80-4 SP - 307 EP - 343 PB - World Scientific Publishing Co. Pte. Ltd. AN - OPUS4-46321 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Effner, Ute A1 - Mielentz, Frank A1 - Niederleithinger, Ernst A1 - Friedrich, C. A1 - Mauke, R. A1 - Mayer, K. T1 - Prüfung von Abdichtbauwerken für Endlager auf Risse – eine Herausforderung N2 - Im Jahr 2011 hat der Bundestag in Deutschland den Ausstieg aus der Kernenergie beschlossen. Der angefallene Abfall wird mehr als hunderttausend Jahre eine derartig hohe Aktivität besitzen, dass er eine erhebliche Gefahr für nachfolgende Generationen darstellen kann. Dieser radioaktive Abfall soll in tiefen geologischen Formationen (z.B. Salz, Ton oder Kristallin) sicher endgelagert werden. Die Endlager werden mittels sogenannter geotechnischer Abdichtbauwerke (Schachtbzw. Streckenverschlüsse) verschlossen, wofür u.a. Zement- oder Sorel-basierte Baustoffe (Betone) in Frage kommen. Die Beschreibung des Dichtvermögens dieser Bauwerke ist unabdingbar. In der Forschungsphase werden verschiedene Werkstoffe untersucht und Methoden für die zerstörungsfreie Untersuchung der Bauwerke als Mittel der Qualitätsprüfung entwickelt. Hierbei ist der Nachweis der Rissfreiheit bzw. die Detektion möglicher Risse ein vorrangiges Thema. In den letzten Jahren konnten bereits umfangreiche Erfahrungen mit der Untersuchung von in-situ-Versuchsobjekten in Realmaßstab gesammelt werden. Die Messungen wurden im Endlager für radioaktive Abfälle Morsleben am in-situ-Versuch “Abdichtbauwerk im Steinsalz” und in der Grube Teutschenthal am Großversuch GV2 durchgeführt. Es ist gelungen mit einem neu entwickelten Ultraschall-Messsystem Eindringtiefen bis ca. 9,0 m zu realisieren. Die Messungen mit dem Large Aperture Ultrasonic System in Kombination mit der Rekonstruktion-Methode Synthetic Aperture Focusing Technique zeigen, dass die zerstörungsfreie Prüfung von Abdichtbauwerken möglich und die Nutzung des Messsystems zur Qualitätssicherung bei der Erstellung der Verschlussbauwerke vielversprechend ist. N2 - In 2011, the German Bundestag decided to phase out nuclear energy. The resulting waste will remain highly radioactive for many hundreds of thousands of years and represents a considerable danger for future generations. This radioactive waste is to be safely disposed of in deep geological formations (e.g. salt, clay or crystalline). The repositories will be sealed by means of engineered barrier systems. The impermeability of these structures is indispensable. In the current research phase, various materials are being investigated and methods for monitoring the structures are being developed. In this context, the investigation of cracks is a priority topic. In recent years, BAM has gained extensive experience in the investigation of in-situ test objects in full scale. The measurements were performed in the Morsleben repository for radioactive waste at the test structure for the in-situ experiment "Sealing structure in rock salt" and in the Teutschenthal mine at the large-scale GV2 test structure. With a newly developed ultrasonic measuring system it has been possible to achieve penetration depths of up to approx. 9.0 m. Measurements with the Large Aperture Ultrasonic System in combination with the Synthetic Aperture Focusing Technique reconstruction method show that the non-destructive testing of sealing structures is possible and the use of the measuring system for quality assurance in the construction of sealing structures is promising. KW - Abdichtbauwerk / Verschlussbauwerk KW - Zerstörungsfreie Prüfung KW - Large Aperture Ultrasonic System KW - Synthetic Aperture Focusing Technique KW - Ultraschall-Echo-Verfahren PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-520298 DO - https://doi.org/10.1002/mawe.202000118 SN - 1521-4052 VL - 52 IS - 1 SP - 19 EP - 31 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-52029 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fahmy, A. A1 - Al-Nasser, K. S. A1 - Ali, I. O. A1 - Salama, T. M. A1 - Altmann, Korinna A1 - Friedrich, J. F. T1 - Tuning of adhesion of silver nanoparticles onto zeolite ZSM-5 using electrospray ionization (ESI) encapsulation with poly(acrylic acid) deposited by electrospray ionization (ESI) N2 - The electrospray ionization (ESI) method was used for deposition of thin films of poly(acrylic acid) (PAA) onto ZSM-5, Cu/ZSM-5 and Ag-Cu/ZSM-5 zeolites. This method allowed the formation of uniform polymer films of controlled thickness on conductive substrates. The zeolites were prepared home-made. The effect of incorporation of Cu (5 wt.%) and Ag-Cu (1+4 wt.%) onto ZSM-5 on its particle size, unit cell parameters and crystallinity was investigated. The deposited PAA layer acts as a common dispersing agent with its ionic COOH (COO-) groups. The antibacterial activity towards the bacterial strains such as Staphylococcus pneumonia (S. Pneumonia), Bacillus subtilis (B. subtilis), Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) as Gram positive and Gram negative bacteria, respectively, and Aspergillus fumigatus (A. fumigatus), Candida albicans (C. albicans) as Fungi was evaluated. The chemical and physical modifications of ZSM-5, Cu/ZSM-5 and Ag-Cu/ZSM-5 surfaces were characterized by X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, atomic force microscopy and X-ray diffraction. The Cu/ZSM-5 and Ag-Cu/ZSM-5 nanocomposites coated with a 10 nm thick PAA layer exhibit significant antibacterial activity. The carboxyl (¬-COOH) or the corresponding carboxylate groups (¬-COO-) interact with Cu2+ and Ag+ ions by formation of ionic bonds (¬-COO-Ag+ or 2 ¬-COO->Cu2+). Moreover, short exposure to light and temperature has reduced Cu2+ and Ag+ to Cu0 and Ag0. KW - Elektrospray Ionization KW - Silver nanoparticles KW - Adhesion PY - 2017 DO - https://doi.org/10.1080/01694243.2017.1315910 VL - 31 IS - 24 SP - 2641 EP - 2656 PB - Taylor & Francis CY - Adingdon AN - OPUS4-40506 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kowalski, Kurt A1 - Hulshoff, S.J. A1 - Ströer, P. A1 - Withag, J. A1 - Genot, A. A1 - Morgans, A.S. A1 - Bake, Friedrich A1 - Venner, K. A1 - Sanders, M.P.J. A1 - Hirschberg, Lionel T1 - Entropy-patch choked-nozzle interaction: quasi-steady-modeling-regime limits probed N2 - Indirect combustion noise due to the interaction of flow inhomogeneities with a choked combustion-chamber exit is an important cause of combustion instability in solid rocket motors. Moreover, it is believed to be an issue in electrical-power generation turbines and aero-engines. If these flow inhomogeneities are essentially characterized by the fluid having a locally appreciablydifferent thermodynamic state, the acoustic response engendered by its interaction with the combustion-chamber exit is commonly referred to as entropy noise. In this paper, dedicated numerical-simulation results of entropy-patch choked-nozzle interactions are presented. Two types of entropy patches were considered: rectangular slugs and circular spots. Moreover, analytical-model-based analysis, of said simulation results, is presented. Based on said analysis, the authors posit the existence of three modeling regimes: the quasi-steady-modeling regime, the blended-physical-effects regime, and the inertial-modeling regime. T2 - 30th AIAA/CEAS Aeroacoustics Conference (2024) CY - Rome, Italy DA - 04.06.2024 KW - Entropy-Nozzle Interaction KW - Indirect Combustion Noise KW - Entropy Noise PY - 2024 DO - https://doi.org/10.2514/6.2024-3113 SP - 1 EP - 23 AN - OPUS4-60174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mierczynska, A. A1 - Friedrich, Jörg Florian A1 - Maneck, Heinz-Eberhard A1 - Boiteux, G. A1 - Jeszka, J.K. T1 - Segregated network polymer/carbon nanotubes composites N2 - In this work we present the preparation of conductive polyethylene/carbon nanotube composites based on the segregated network concept. Attention has been focused on the effect of decreasing the amount of filler necessary to achieve low resistivity. Using high- and low-grade single-walled carbon nanotube materials we obtained conductive composites with a low percolation threshold of 0.5 wt.% for high-grade nanotubes, about 1 wt% for commercial nanotubes and 1.5 wt% for low-grade material. The higher percolation threshold for low-grade material is related to low effectiveness of other carbon fractions in the network formation. The electrical conductivity was measured as a function of the single-walled carbon nanotubes content in the polymer matrix and as a function of temperature. It was also found that processing parameters significantly influenced the electrical conductivity of the composites. Raman spectroscopy was applied to study single wall nanotubes in the conductive composites. KW - Polymer KW - Single-walled carbon nanotubes KW - Composite KW - Segregated network KW - Sintering KW - Conductivity KW - Raman spectroscopy PY - 2004 DO - https://doi.org/10.2478/BF02475579 SN - 1644-3624 SN - 1895-1066 VL - 2 IS - 2 SP - 363 EP - 370 PB - Central European Science Journals CY - Warsaw AN - OPUS4-3583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Grytsenko, K.P. A1 - Lytvyn, P. A1 - Friedrich, Jörg Florian A1 - Schulze, Rolf-Dieter A1 - Schrader, S. T1 - Influence of plasma discharge on the structure of polytetrafluoroethylene film and step coverage on polymer substrate N2 - Polytetrafluoroethylene (PTFE) films have been deposited onto polycarbonate (PC) substrates from the products of PTFE evaporation, activated by a cloud of accelerated electrons. A 40.68 MHz glow discharge was used during the deposition process. The polymer films have been characterised by XPS, FTIR and AFM. The use of the low power plasma during film growth led to the formation of PTFE films with modified structure. Films are amorphous and contain more cross-links, but in general, the structure of their macromolecules is still linear. An increase of RF-power leads to the formation of films with large amount of double bonds and enhanced internal stresses. Deposition of PTFE on PC without plasma treatment led to the formation of PTFE clusters up to 50 nm in diameter. The RMS roughness of the films, deposited without plasma, was about 4 nm, while the films deposited with plasma treatment had a roughness of 1.5 nm. The use of plasma has an additional effect if a PTFE coating is deposited on the PC substrate with submicrometer-sized steps. Without plasma the steps retain a rectangular shape. Deposited with the RF-discharge the PTFE layers resemble plasma-polymerised films. Under certain conditions the deposited films can fill trenches in the substrate like a wetting liquid, while under other conditions they avoid trenches and grow in between them. KW - Polytetrafluoroethylene KW - PTFE KW - Vacuum deposition KW - Plasma KW - Discharge KW - Film PY - 2007 DO - https://doi.org/10.1016/j.msec.2006.09.029 SN - 0928-4931 SN - 1873-0191 VL - 27 IS - 5-8 SP - 1227 EP - 1231 PB - Elsevier CY - Amsterdam AN - OPUS4-14014 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dimitriev, O.P. A1 - Grytsenko, K.P. A1 - Lytvyn, P.M. A1 - Doroshenko, T.P. A1 - Briks, J.L. A1 - Tolmachev, A.I. A1 - Slominskii, Y.L. A1 - Kudinova, M.A. A1 - Schrader, S. A1 - Schulze, Rolf-Dieter A1 - Friedrich, Jörg Florian T1 - Substrate-induced self-assembly of donor-acceptor type compounds with terminal thiocarbonyl groups N2 - Two types of conjugated thiocarbonyl-terminated compounds have been synthesized and their ability to be adsorbed on surfaces of the different nature, namely, glass, polytetrafluoroethylene (PTFE), and gold has been studied. Different morphology of the films prepared by thermal vacuum evaporation and drop-casting from solutions has been observed depending on the surface used. It has been found that gold surface has a unique property to influence self-assembly of both monolayer and larger aggregates or crystals of the compounds, in contrast to glass and PTFE substrates. It was found that thiocarbonyl group is able to be chemisorbed to the gold surface. However, it was concluded that in spite of the fact that the thiocarbonyl groups are important for the chemical interaction with the gold surface, physical adsorption on the substrate surface, compound–compound and compound–solvent (when using solution) interactions are of great significance to drive self-assembly of the final film. KW - Thiocarbonyl group KW - Donor–acceptor compound KW - Gold surface KW - Aggregation KW - Film morphology PY - 2013 DO - https://doi.org/10.1016/j.tsf.2013.05.084 SN - 0040-6090 VL - 539 SP - 127 EP - 133 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-30571 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -