TY - JOUR A1 - Bayerl, C. A1 - Shahryari, M. A1 - Reiter, R. A1 - Proß, V. A1 - Lehmann, K. A1 - Kühl, A. A. A1 - Becker, Dorit A1 - Schulz, Andreas A1 - Infante Duarte, C. A1 - Taupitz, M. A1 - Geisel, D. A1 - Tzschätzsch, H. A1 - Saatz, Jessica A1 - Traub, Heike A1 - Asbach, P. T1 - Quantitative Analysis of Gadolinium Deposits in Liver Tissue of Patients After Single or Multiple Gadolinium-based Contrast Agent Application N2 - Gadolinium-based contrast agents (GBCAs) are widely used in magnetic resonance imaging. Concerns exist regarding gadolinium deposition and its potential histopathologic tissue alterations, especially after repeated administrations of linear, less stable GBCAs. This study aimed to quantify gadolinium mass fractions in liver specimens of subjects exposed to GBCAs in correlation with histopathologic features. In this study, mass fractions of gadolinium in human liver specimens from 25 subjects who underwent liver tumor resection surgery and had received GBCA (1 to 9 times over 4 years), were quantitatively analyzed using inductively coupled plasma–mass spectrometry (ICP-MS). Histomorphology was assessed based on the nonalcoholic fatty liver disease activity score (NAS). Our results suggest that after intravenous administration of GBCA, a small fraction of gadolinium is retained in the liver over a time period of at least several weeks. A relationship was observed between Gadolinium retention and the number of GBCA administrations, but not with the cumulative dose and the degree of fatty liver disease. KW - ICP-MS KW - Contrast agent KW - Gadolinium KW - Liver PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-646608 DO - https://doi.org/10.1097/RLI.0000000000001254 SN - 1536-0210 SP - 1 EP - 10 PB - Lippincott Williams & Wilkins CY - Philadelphia, Pa. AN - OPUS4-64660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gaebler, A. A1 - Moessinger, A. A1 - Goelden, F. A1 - Manabe, A. A1 - Goebel, M. A1 - Follmann, R. A1 - Koether, D. A1 - Modes, C. A1 - Kipka, A. A1 - Deckelmann, M. A1 - Rabe, Torsten A1 - Schulz, Bärbel A1 - Kuchenbecker, Petra A1 - Lapanik, A. A1 - Mueller, S. A1 - Haase, W. A1 - Jakoby, R. T1 - Liquid crystal-reconfigurable antenna concepts for space applications at microwave and millimeter waves N2 - Novel approaches of tunable devices for millimeter wave applications based on liquid crystal (LC) are presented. In the first part of the paper, a novel concept of a tunable LC phase shifter realized in Low Temperature Cofired Ceramics technology is shown while the second part of the paper deals with a tunable high-gain antenna based on an LC tunable reflectarray. The reflectarray features continuously beam scanning in between ±25°. Also first investigations on radiation hardness of LCs are carried out, indicating that LCs might be suitable for space applications. KW - Tunable antenna KW - Phase shifter KW - Liquid crystal KW - LTCC PY - 2009 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-194273 DO - https://doi.org/10.1155/2009/876989 SN - 1687-5877 VL - 2009 IS - Article ID 876989 SP - 1 EP - 7 PB - Hindawi Publishing Corporation CY - New York, NY, USA AN - OPUS4-19427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Knelles, J. A1 - Wanner, C. A1 - Schulz, F. A1 - Freund, M. A1 - Kolmangadi, Mohamed Aejaz A1 - Baro, A. A1 - Huber, P. A1 - Schönhals, Andreas A1 - Lachat, S. T1 - Liquid crystalline hydrazones revisited: dipolar interactions vs hydrogen bonding affecting mesomorphic properties N2 - In order to understand the role of dipolar interactions vs. H-bonding, a series of hydrazones were synthesised from 4-alkoxy-, 3,4-dialkoxy- or 3,4,5-trialkoxybenzaldehydes and phenyl, bromo- or nitrophenylhydrazine, respectively. Their mesomorphic properties were investigated by differential scanning calorimetry (DSC), polarising optical microscopy (POM), X-ray diffraction (WAXS, SAXS) and compared with known members. Only those hydrazones derived from 3,4,5-trisalkoxybenzaldehyde and either meta, meta-dinitro- or ortho, para-dinitrophenylhydrazine displayed hexagonal columnar mesophases. All other derivatives were non-mesomorphic, even when H-bonds were present. Dipole moments of the various nitro-substituted hydrazones were experimentally determined by dielectric measurements and supported by theoretical DFT calculations, which indicated that the mesophase formation is mostly governed by strong dipole moment and further enforced by intramolecular H-bonding. KW - Discotic liquid crystals PY - 2021 DO - https://doi.org/10.1080/02678292.2021.1873438 VL - 48 IS - 10 SP - 1382 EP - 1391 PB - Taylor & Francis AN - OPUS4-52409 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Griesche, Axel A1 - Pfretzschner, Beate A1 - Schaupp, Thomas A1 - Schulz, M. A1 - Kardjilov, N. ED - Duprez, Lode T1 - Hydrogen in steel visualized by neutron imaging N2 - Neutron cameras allow visualizing hydrogen distributions with radiographic or tomographic imaging methods in iron and steel. The necessary contrast between hydrogen and iron stems from the high difference in the total neutron cross section of both elements. This allows e.g. the in situ measurement of hydrogen mass flow inside cm thick steel samples with a temporal resolution of 20 s using neutron radiography as well as the quantitative measurement of hydrogen accumulations at the crack’s inner surfaces in hydrogen embrittled iron samples with neutron tomography. We could detect directly gaseous hydrogen in the crack cavities and we measured the gas pressure. This new quality of the information on a micrometer scale allows new insights for the analysis of hydrogen-induced damage mechanisms. Further, this method is non-destructive and provides local information in situ and in three dimensions with a spatial resolution of 20-30 µm. In this contribution, we show examples that demonstrate the spatial and temporal resolution of the neutron radiography and tomography methods in order to visualize and quantify hydrogen accumulations at cracks. The measurements were performed at the research reactor BER II of the HZB in Berlin and at the FRM II reactor of the neutron source Heinz Maier-Leibnitz in Garching. T2 - Third International Conference on Metals & Hydrogen CY - Ghent, Belgium DA - 29.05.2018 KW - Hydrogen KW - Steel KW - Neutron imaging PY - 2018 SN - 978-9-08179-422-0 SP - J01 AN - OPUS4-45359 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kaiser, T. M. A1 - Braune, C. A1 - Kalinka, Gerhard A1 - Schulz-Kornas, E. T1 - Nano-indentation of native phytoliths and dental tissues: implications for herbivore-plant combat and dental wear proxies N2 - Tooth wear induced by abrasive particles is a key process affecting dental function and life expectancy in mammals. Abrasive particles may be plant endogenous opal phytoliths, exogene wind-blown quartz dust or rain borne mineral particles ingested by mammals. Nano-indentation hardness of abrasive particles and dental tissues is a significant yet not fully established parameter of this tribological system. We provide consistent nano-indentation hardness data for some of the major antagonists in the dental tribosystem (tooth enamel, tooth dentine and opaline phytoliths from silica controlled cultivation). All indentation data were gathered from native tissues under stable and controlled conditions and thus maximize comparability to natural systems. Here we show that native (hydrated) wild boar enamel exceeds any hardness measures known for dry herbivore tooth enamel by at least 3 GPa. The native tooth enamel is not necessarily softer then environmental quartz grit, although there is little overlap. The native hardness of the tooth enamel exceeds that of any silica phytolith hardness recently published. Further, we find that native reed phytoliths equal native suine dentine in hardness, but does not exceed native suine enamel. We also find that native suine enamel is significantly harder than dry enamel and dry phytoliths are harder than native phytoliths. Our data challenge the claim that the culprit of tooth wear may be the food we chew, but suggest instead that wear may relates more to exogenous than endogenous abrasives. KW - Phytolith KW - Indentation hardness KW - Enamel KW - Dentine KW - Tooth wear PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-451417 UR - http://zoobank.org/5C7DBB2B-B27D-4CE6-9656-33C4A0DA0F39 DO - https://doi.org/10.3897/evolsyst.2.22678 VL - 2 SP - 55 EP - 63 PB - PENSOFT CY - USA AN - OPUS4-45141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Eh Hovsepian, P. A1 - Ehiasarian, A. P. A1 - Purandare, Y. P. A1 - Mayr, P. A1 - Abstoss, K. G. A1 - Mosquera Feijoo, Maria A1 - Schulz, Wencke A1 - Kranzmann, Axel A1 - Lasanta, M. I. A1 - Trujillo, J. P. T1 - Novel HIPIMS deposited nanostructured CrN/NbN coatings for environmental protection of steam turbine components N2 - To increase efficiency, modern steam plants are pushing their operational regime from super-critical (600 °C/300 bar) to ultra-super-critical (740/760 °C/350 bar) stretching existing turbine materials to their limits. The focus is on new generation functional materials and technologies which complement the inherent properties of existing materials. Current work proposes a novel High Power Impulse Magnetron Sputtering (HIPIMS) Deposition technology, for the first time, for deposition of a ceramic based CrN/NbN coating with a nanoscale multilayer structure (bi-layer thickness Δ = 1.9 nm) with superior adhesion (LC2 = 80 N) to protect low Chromium P92 steel widely used in steam power plants. Thermodynamic calculations predict the equilibrium phases and aggressive gaseous compounds generated by the interaction of steam with the coating. CrN/NbN coated P92 steel samples oxidised at 600 °C in a high pressure (50 bar) 100% steam atmosphere for up to 1000 h reveal the coating's superior oxidation resistance and protective mechanisms, especially against the detrimental effect of Hydrogen. High temperature (650 °C) Tensile Strength, Low Cycle Fatigue and Creep tests confirm that, unlike other state-of-the-art PVD technologies, HIPIMS is not detrimental to the mechanical properties of the substrate material. Water droplet erosion tests confirm no measurable weight loss after 2.4 X 10⁶ impacts. KW - Hipims KW - CrN/NbN KW - Nanoscale multilayers KW - Steam oxidation resistance KW - Water droplet erosion resistance PY - 2018 DO - https://doi.org/10.1016/j.jallcom.2018.02.312 SN - 0925-8388 SN - 1873-4669 VL - 746 SP - 583 EP - 593 PB - Elsevier AN - OPUS4-44800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stephan-Scherb, Christiane A1 - Schulz, Wencke A1 - Schneider, M. A1 - Karafiludis, Stephanos A1 - Laplanche, G. T1 - High-Temperature Oxidation in Dry and Humid Atmospheres of the Equiatomic CrMnFeCoNi and CrCoNi High- and Medium-Entropy Alloys N2 - Surface degradation phenomena of two model equiatomic alloys from the CrMnFeCoNi alloy system were investigated in 2% O2 and 10% H2O (pO2 = 0.02 and 10−7 atm, respectively) at 800 °C for times up to 96 h. The crystallographic structures, morphologies, and chemical compositions of the corrosion layers developing on CrMnFeCoNi and CrCoNi were comparatively analyzed by mass gain analysis, X-ray diffraction, and scanning electron microscopy combined with energy-dispersive X-ray spectroscopy and electron backscatter diffraction. The oxidation resistance of CrMnFeCoNi is relatively poor due to the fast growth of porous Mnoxide(s). CrCoNi forms an external chromia layer that is dense and continuous in a dry 2% O2 atmosphere. This layer buckles and spalls off after exposure to 10% H2O atmosphere. Beneath the chromia layer, a Cr-depleted zone forms in the CrCoNi alloy in both environments. As the oxide scale spalls off in the H2O-containing atmosphere, a secondary chromia layer was observed and correspondingly enlarges the Cr-depleted zone. In contrast, as the chromia layer remains without significant spallation when CrCoNi is exposed to a dry oxidizing atmosphere, the region depleted in Cr is narrower. KW - High temperature oxidation KW - High entropy alloys KW - Medium entropy alloys KW - CrMnFeCoNi KW - CrCoNi KW - Mn-oxides PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517859 DO - https://doi.org/10.1007/s11085-020-10014-7 SN - 0030-770X VL - 95 IS - 1-2 SP - 105 EP - 133 PB - Springer AN - OPUS4-51785 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Malow, Marcus A1 - Michael-Schulz, Heike A1 - Duerrstein, St. A1 - Kappler, C A1 - Neuhaus, I. A1 - Gödde, M. T1 - Model-Based Prediction of the Adiabatic Induction Period and SADT of Dicumyl Peroxide Solution and Comparison to Large-Scale Experiments Performed Using 216.5-Liter Steel Drums in the UN-Test H.1 N2 - The thermal decomposition of dicumyl peroxide dissolved in ethylbenzene has been studied in our laboratories using differential scanning calorimetry (DSC), calvet calorimetry (C80), adiabatic calorimetry, reaction calorimetry and micro calorimetry. Based on the DSC and C80 experiments a formal kinetics model has been derived, which was compared to the other applied techniques. Finally we used our model to predict the thermal response of 216.5 L steel drums to exposure to constant elevated temperatures, both using the stationary Semenov approach as well as time-resolved CFD simulations. The prediction was compared to one-to-one testing using the UN-Test H.1. The observed level of consistency between model and experiments is remarkably good. The comparison with the 216.5 L testing clearly demonstrates that reliable and conservative predictions for technically relevant scales are possible as long as a validated model is used. T2 - 15th International Symposium of Loss Prevention and Safety Promotion in the Process Industries CY - Freiburg, Germany DA - 05.06.2016 KW - Thermal decomposition KW - Self-accelerating decomposition temperature KW - Dicumyl peroxide KW - CFD simulations KW - Real scale FST PY - 2016 SN - 978-88-95608-39-6 DO - https://doi.org/10.3303/CET1648080 SN - 2283-9216 VL - 48 SP - 475 EP - 480 PB - AIDIC CY - Freiburg AN - OPUS4-37875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baytekin, H.T. A1 - Baytekin, B. A1 - Schulz, a. A1 - Springer, A. A1 - Gross, Thomas A1 - Unger, Wolfgang A1 - Artamonova, M. A1 - Schlecht, S. A1 - Lentz, D. A1 - Schalley, C.A. T1 - Metallo-supramolecular nanospheres via hierarchical self-assembly N2 - A novel coordination oligo/polymer is synthesized by metal-directed self-assembly from equimolar amounts of the (dppp)M(OTf)2 precursor complexes (dppp = bis-(diphenylphosphino)-propane, OTf = triflate; M = PdII or M = PtII) and banana-shaped bidentate dipyridyl ligands. The assemblies were characterized by ESI mass spectrometry and NMR spectroscopy. The analysis of the cloudy suspension prepared by dissolving the coordination polymer in aqueous methanol solutions indicates nanosized spherical objects to form. Evidence for vesicle formation from these metallo-supramolecular oligomers comes from (cryogenic) transmission electron microscopy (TEM, cryo-TEM). Atomic force microscopy revealed stable nanospheres on hydrophilic mica and monolayer formation on hydrophobic highly oriented pyrolitic graphite (HOPG) substrates. On mica, also torus-shaped object were observed, which are rationalized by vesicles that opened during the drying procedure and released the internal solvent. Elemental analysis of the nanoassemblies by X-ray photoelectron spectroscopy (XPS) indicates uncoordinated and coordinated pyridines in the coordination polymers that form the nanospheres. Various control experiments using different metal centers and modified ligands support the conclusions. KW - Self-assembly KW - Metallo-supramolecular chemistry KW - Coordination polymers KW - Vesicles KW - Electron microscopy KW - Nano-materials PY - 2009 DO - https://doi.org/10.1021/cm900642p SN - 0897-4756 SN - 1520-5002 VL - 21 IS - 13 SP - 2980 EP - 2992 PB - American Chemical Society CY - Washington, DC AN - OPUS4-19638 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bartoszek, M. A1 - Eckelt, R. A1 - Jäger, Christian A1 - Kosslick, H. A1 - Pawlik, Alf A1 - Schulz, A. T1 - Mesoporous silica-aluminas derived from precipitation: a study of the acidity, textural properties and catalytic performance KW - Silica-alumina KW - Solid state NMR KW - Acidity KW - Silicates KW - Tetrahedral aluminium PY - 2009 DO - https://doi.org/10.1007/s10853-009-3580-y SN - 0022-2461 SN - 1573-4803 VL - 44 IS - 24 SP - 6629 EP - 6636 PB - Springer Science + Business Media B.V. CY - Norwell, Mass. AN - OPUS4-20462 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Retzko, Iris A1 - Treu, Dieter A1 - Matsubayashi, N. A1 - Imamura, M. A1 - Tanaka, T. A1 - Schulz, H. A1 - Lippitz, Andreas A1 - Unger, Wolfgang T1 - Analysis of carbon materials and plasma polymers by X-ray photoelectron spectroscopy and X-ray absorption spectroscopy (XPS, XAS) T2 - AIST-BAM Symposium on Materials Surface Technology in Twin Institute Programme CY - Tsukuba, Japan DA - 2003-02-18 PY - 2003 SP - 59 EP - 65 AN - OPUS4-6928 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krüger, Ralph-Peter A1 - Much, Helmut A1 - Paulus, G. A1 - Resch, M. A1 - Schulz, Günter ED - Darms, R. ED - Suter, U. T1 - Polymer Characterization by MALDI-TOF-MS and Combination with HPLC T2 - 5th European Polymer Federation Symposium on Polymeric Materials (EPF) CY - Basel, Switzerland DA - 1994-10-09 PY - 1994 SN - 3-85739-297-5 SN - 0258-0322 VL - 5 PB - Hüthig & Wepf CY - Zug AN - OPUS4-2200 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brehme, R. A1 - Gründemann, E. A1 - Schneider, M. A1 - Radeglia, Reiner A1 - Reck, Günter A1 - Schulz, Burkhard T1 - Aza-enamines X - Formylation of Pyrazole-4-carbaldehyde Hydrazones at the Hydrazonoazomethine C-Atom N2 - 1,3-Disubstituted 1H-pyrazole-4-carbaldehyde-N,N-di­methylhydrazones 1 reacted with the Vilsmeier-Haackreagent, corresponding to the aza-enamine concept, in an electrophilicsubstitution reaction at the azomethine C-atom yielding the 1,4,5-triaza-pentadieniumsalts 2. These were hydrolysed to give2-hydrazono-2-(1H-pyrazole-4-yl)ethanals 3. The electrophilic attack did not takeplace at the vinylogous position 5' of the pyrazoles. KW - Aza-enamines KW - Hydrazones KW - Heterocycles KW - Formylation KW - Alpha-oxoethanals PY - 2003 DO - https://doi.org/10.1055/s-2003-40527 SN - 0039-7881 SN - 1437-210X IS - 10 SP - 1615 EP - 1619 PB - Thieme [u.a.] CY - Stuttgart AN - OPUS4-2617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Ralph-Peter A1 - Much, Helmut A1 - Pickard, M. A1 - Schulz, Günter A1 - Wachsen, O. T1 - Characterization of thermal and hydrolytic degradation of polylactides by Liquid Chromatography and MALDI-TOF mass spectrometry T2 - International Symposium on "Biodegradable Materials" and Hamburger Makromolekulares Symposium CY - Hamburg, Germany DA - 1996-10-07 PY - 1996 CY - Hamburg AN - OPUS4-2225 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hintz, M. A1 - Thust, H. A1 - Rabe, Torsten A1 - Schulz, Bärbel T1 - Neue Technologievarianten von LTCC durch druckunterstütztes Sintern KW - LTCC KW - Drucksintern KW - Metallisieren PY - 2004 SN - 0173-9913 SN - 0196-6219 VL - 18 IS - 1 SP - 174 EP - 179 PB - Göller CY - Baden-Baden AN - OPUS4-5339 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bismarck, A. A1 - Pfaffernoschke, M. A1 - Springer, J. A1 - Schulz, Eckhard T1 - Polystyrene-grafted Carbon Fibers: Surface Properties and Adhesion to Polystyrene N2 - It is highly desirable to improve attractive interactions between carbon fibers and unreactive thermoplastic matrices to the possible maximum. This could be achieved by a simple grafting process to create a covalently bonded interface or interlayer, which should result in cohesive interactions between the polymer-grafted fibers and the same matrix material, leading to a better adhesion strength in the obtained composite material. Here, we are describing the grafting of styrene onto unmodified and unsized carbon fibers via free-radical bulk polymerization in the presence of fibers. After grafting, the surface properties of the carbon fiber approach those of pure polystyrene which was proven by contact angle and zeta ({zeta}) potential measurements. As indicated by the water contact angle, the carbon fiber surface becomes more hydrophobic. Scanning electron microscopy (SEM) provides evidence of grafted polymer. This simple procedure results in a continuous polystyrene coating. The fiber diameter increases significantly after polymer grafting. The adhesion and fracture behavior between the original and polystyrene-grafted carbon fibers to a polystyrene (VESTYRON®) matrix was characterized using the single-fiber pull-out test. There is a considerable increase in the measurable adhesion, i.e., the interfacial shear strength IFSS, by almost 300% between the grafted fibers and polystyrene as compared to untreated original fibers. Two planes of interfacial failure could be distinguished; first in the fiber coating interface leading to lower interfacial shear strength and second in the PS-matrix-PS-coating interphase resulting in a higher interfacial shear strength. In addition to the improved adhesion, there are also clear differences in the pull-out behavior between the nongrafted and grafted fibers. After the initial debonding process corresponding to the maximal pull-out force is completed, the pull-out force is increasing again. PY - 2005 DO - https://doi.org/10.1177/0892705705049559 SN - 0892-7057 SN - 1530-7980 VL - 18 IS - 4 SP - 307 EP - 331 PB - Sage Publ. CY - London AN - OPUS4-11599 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rabe, Torsten A1 - Kuchenbecker, Petra A1 - Schulz, Bärbel A1 - Schmidt, M. T1 - Hot Embossing: An Alternative Method to Produce Cavities in Ceramic Multilayer N2 - New applications of ceramic multilayers, for example, in biotechnology, sensor technology, and chemical micro-reaction technique, call for cavities with complex geometries. Hot embossing offers a promising, cost-effective way to generate these structures on the surfaces of green tapes or laminates. Cavities inside low-temperature co-fired ceramic multilayer were manufactured by a combination of hot embossing, lamination by a special adhesive technique, and zero shrinkage sintering. The edge and surface quality in the green state as well as the sintered multilayers with surface structures and cavities were extensively characterized by laser surface scanning, optical and ultrasound microscopy. Sintering shrinkage of hot-embossed laminates could be reduced in the x and y directions to less than 0.5%. KW - Keramische Multilayer KW - LTCC KW - Lamination KW - Heißprägen KW - Zero Shrinkage Sinterung PY - 2007 DO - https://doi.org/10.1111/j.1744-7402.2007.02117.x SN - 1546-542X SN - 1744-7402 VL - 4 IS - 1 SP - 38 EP - 46 PB - American Ceramic Soc. CY - Westerville, Ohio AN - OPUS4-16125 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kosslick, H. A1 - Pitsch, I. A1 - Deutsch, J. A1 - Pohl, M.-M. A1 - Schulz, A. A1 - Vu, A.T. A1 - Nguyen, D.T. A1 - Frunza, L. A1 - Jäger, Christian T1 - Improved large mesoporous ordered molecular sieves - Stabilization and acid/base functionalization N2 - The preparation of nanoporous materials with enhanced stability using an improved synthesis route using reactive inorganic silica and alumina species is reported. This way improved mesoporous molecular sieves were obtained. The synthesized aluminum substituted mesoporous molecular materials (Al-MMS) contain very large pores of 50–200 Å size combined with an improved pore wall thickness. Increased wall thickness and Al substitution lead to an improved chemical stability against alkaline solution. The textural, structural and acid properties are investigated by physico-chemical methods. The catalytic performance acidic materials was tested in the benzoylation reaction; amino functionalized materials were studied in the base catalyzed Michael addition. KW - Nanoporous molecular sieve KW - Al substitution KW - Stability KW - Synthesis KW - Acidity KW - Catalysis PY - 2010 DO - https://doi.org/10.1016/j.cattod.2010.03.005 SN - 0920-5861 VL - 152 IS - 1-4 SP - 54 EP - 60 PB - Elsevier CY - Amsterdam AN - OPUS4-23960 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Culleton, L.P. A1 - Brown, A. A1 - Murugan, A. A1 - Van der Veen, A. A1 - Van Osselen, D. A1 - Ziel, P. R. A1 - Li, J. A1 - Tuma, Dirk A1 - Schulz, Gert A1 - Näther, Stephanie A1 - Arrhenius, K. A1 - Kühnemuth, D. A1 - Beránek, J. A1 - Fuko, J. A1 - Val'ková, M. T1 - Results of an international comparison on the analysis of real nonconventional energy gases N2 - The requirement for a metrological infrastructure to ensure the interchangability of 'nonconventional’ energy gases within existing European infrastructure1 was the driving force behind the work undertaken in the three-year EMRP Characterisation of energy gases project EMRP ENG01 (June 2010 - May 2013). As part of work package one of the project, Standards and methods were used to perform composition and impurity measurements on samples of real energy gases collected from around Europe. The aim of this study was to compare the results obtained from different labs, and thereby provide an evaluation of the labs’ capabilities and provide insight into the feasibility of different analytical methodologies for use with future measurements. KW - Energy gases KW - Real samples KW - Sampling KW - Analysis PY - 2013 SN - 1754-2928 IS - July SP - 1 EP - 28 PB - Queen's Printer and Controller of HMSO CY - Teddington, Middlesex, UK AN - OPUS4-29449 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stock, H.-R. A1 - Schulz, A. A1 - Kopnarski, M. A1 - Gross, Thomas ED - Ricard, A. T1 - Standards for composition-depth profiles of TiN, Ti(C, N) and (Ti, Al)N with different chemical composition T2 - 5th International Conference on Plasma Surface Engineering (PSE) CY - Garmisch-Patenkirchen, Germany DA - 1996-09-09 KW - Beschichtung KW - Plasma PY - 1996 SN - 0257-8972 VL - 97 IS - 1-3 SP - 181 PB - Elsevier CY - Amsterdam AN - OPUS4-636 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Giebler, Rainer A1 - Unger, Wolfgang A1 - Schulz, B. A1 - Reiche, J. A1 - Brehmer, L. A1 - Wühn, M. A1 - Wöll, Ch. A1 - Smith, A.P. A1 - Urquhart, S.G. T1 - Near-Edge X-ray Absorption Fine Structure Spectroscopy on Ordered Films of an Amphiphilic Derivate of 2,5-Diphenyl-1,3,4-Oxadiazole KW - NEXAFS KW - OMBD KW - X-ray Absorption Spectroscopy PY - 1999 SN - 0743-7463 SN - 1520-5827 VL - 15 IS - 4 SP - 1291 EP - 1298 PB - American Chemical Society CY - Washington, DC AN - OPUS4-828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rurack, Knut A1 - Schulz, Burkhard A1 - Reck, Günter A1 - Resch-Genger, Ute A1 - Bricks, J. A1 - Maus, M. T1 - Substituted 1,5-Diphenyl-3-benzothiazol-2-yl-Delta2-pyrazolines - Synthesis, X-ray Structure, Photophysics, and Cation Complexation Properties N2 - The spectroscopic properties of 1-phenyl-3-benzothiazol-2-yl-5-(4-R-phenyl)-2-pyrazolines are strongly dependent on both the electronic nature of the substituent R and solvent polarity. As revealed by spectroscopic studies as a function of solvent polarity as well as temperature, for electron-rich amino donor substituents in polar solvents, deactivation of the strongly emissive charge transfer (CT) state of the basic 1-phenyl-3-benzothiazol-2-yl-2-pyrazoline chromophore has to compete with a fast intramolecular electron transfer (ET) quenching reaction. In the case of the dimethylamino derivative (R = DMA), the rate constant of ET in acetonitrile was determined to ket = 3 × 1010 s-1. This ET process can be utilized for metal ion sensing by introducing nitrogen containing aza crown ether receptor units to the 4-position of the 5-phenyl group. The spectroscopically determined ET rates of the 5-(N-alkyl)anilino substituents, a DMA, a tetrathia- (AT415C5), and a tetraoxa-monoaza-15-crown-5 (A15C5) group, correlate with electrochemical data and increase in the order AT415C5 < A15C5 < DMA. The metal ion sensing abilities of the two crowned derivatives are presented, and the different signaling mechanisms include binding to the crown ether in the 4-R-position, chelate formation in the 3-benzothiazol-2-yl-2-pyrazoline moiety, and electrophotochemical detection. Furthermore, the rigid "pseudo spiro" geometry of the molecules, which holds the three substituents of the central 2-pyrazoline ring in a fixed prearrangement, was confirmed by X-ray structure analysis. KW - Farbstoff KW - Fluoreszenz KW - Kationen KW - Photophysik PY - 2000 DO - https://doi.org/10.1021/jp993404q SN - 1089-5639 SN - 1520-5215 VL - 104 IS - 26 SP - 6171 EP - 6188 PB - Soc. CY - Washington, DC AN - OPUS4-841 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hartmann, S. A1 - Shaporin, A. A1 - Hermann, S. A1 - Bonitz, J. A1 - Heggen, M. A1 - Meszmer, P. A1 - Sturm, Heinz A1 - Hölck, O. A1 - Blaudeck, T. A1 - Schulz, S. E. A1 - Mehner, J. A1 - Gessner, T. A1 - Wunderle, B. T1 - Towards nanoreliability of CNT-based sensor applications: Investigations of CNT-metal interfaces combining molecular dynamics simulations, advanced in situ experiments and analytics N2 - In this paper we present results of our recent efforts to understand the mechanical interface behaviour of single-walled carbon nanotubes (CNTs) embedded in metal matrices. We conducted experimental pull-out tests of CNTs embedded in Pd or Au and found Maximum forces in the range 10 - 102 nN. These values are in good agreement with forces obtained from molecular Dynamics simulations taking into account surface functional Groups (SFGs) covalently linked to the CNT material. The dominant failure mode in experiment is a CNT rupture, which can be explained with the presence of SFGs. To qualify the existence of SFGs on our used CNT material, we pursue investigations by means of fluorescence labeling of surface species in combination with Raman imaging. We also report of a tensile test system to perform pull-out tests inside a transmission electron microscope to obtain in situ images of CNT-metal interfaces under mechanical loads at the atomic scale. T2 - 2015 16th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Microelectronics and Microsystems CY - Budapest, Hungary DA - 20.4.2015 KW - Carbon nanotube CNT KW - Metal matrix KW - Pull-out test KW - Molecular dynamics simulation KW - Surface functional groups KW - Fluorescence labeling KW - Raman imaging KW - Tensile test inside a TEM PY - 2015 SN - 978-1-4799-9950-7 VL - 2015 SP - 1 EP - 8 PB - IEEE AN - OPUS4-37625 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shirai, K. A1 - Namba, K. A1 - Wataru, M. A1 - Völzke, Holger A1 - Wolff, Dietmar A1 - Probst, Ulrich A1 - Jaunich, Matthias A1 - Schulz, Sebastian T1 - Numerical evaluation of the long-term sealing performance of the silver gasket for dual purpose metal cask under high temperature N2 - It is important to evaluate the effect of thermal ageing on the sealing performance of metal gaskets under high temperature for long-term usage. Therefore, in order to gain representative data for this kind of metal-sealed lid System, BAM is currently performing laboratory tests of different gasket types with aluminum and silver jackets at three different temperatures under static conditions up to four years so far, using test flanges for gaskets with full scale cross section diameter but much smaller outer diameter. On the other hand, in order to investigate the applicability of the numerical methodology to evaluate the long-term behavior of the metal gaskets, such as a correlation between seal pressure force and holding time, CRIEPI is developing a modeling method including material tests (tensile and creep tests) at high temperature. In this paper, the applicability of the finite element method (ABAQUS) to predict the recovery displacement and residual seal pressure force of the gasket complex was verified by comparing the calculated values with BAM’s laboratory test results under the joint research agreement between BAM and CRIEPI. T2 - PATRAM 2013 - 17th International symposium on the packaging and transportation of radioactive materials CY - San Francisco, CA, USA DA - 18.08.2013 KW - Metal seals KW - Extended storage KW - Long-term storage KW - Dual purpose cask PY - 2013 SP - 1 EP - 8 PB - Omnipress AN - OPUS4-31947 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Rabe, Torsten A1 - Schulz, Bärbel A1 - Salehi, M. T1 - Alterungsbeständige keramische Federsensoren durch nanostrukturierte Werkstoffe, Präzisionsbearbeitung und hochdielektrische Nanosuspensionen N2 - Das Ziel des Gesamtvorhabens bestand darin, einen neuartigen kapazitiven Sensortyp zur hochauflösenden Bestimmung von Masse- und Gravitationskraftänderungen zu entwickeln. Bisherige Technologien nutzten dafür Federn oder Biegebalken aus gehärteten metallischen Werkstoffen, deren Alterungsverhalten die Präzision der Kräftemessung begrenzen. Grundprinzip des neuen Sensortyps ist es, eine auf die keramische Feder einwirkenden Änderung der Gewichts- oder Gravitationskraft durch eine Erfassung der Kapazitätsänderung am Sensor zu bestimmen. Dazu muss die durch Stauchung oder Dehnung der Feder entstehende Kapazitätsänderung mit hoher Auflösung reproduzierbar gemessen werden. Neben einem geeigneten Sensordesign waren Lösungen für Messsignalerfassung und -auswertung (Elektronik/Software) und die Systemintegration zu entwickeln. Die wichtigsten im Rahmen des BAM-Teilvorhabens erzielten Ergebnisse sind: - Ausgehend von kommerziellen High-end Keramikpulvern wurden durch Optimierung der keramischen Technologie nahezu porenfreie Al2O3, ZrO2 und Si3N4-Werkstoffe hergestellt und bezüglich Gefüge und Phasenbestand sowie mechanischen, thermischen und elektrischen Eigenschaften bewertet. Insbesondere die defektfreie Herstellung von nanostrukturierten Werkstoffen erforderte umfangreiche Variationen der Prozessparameter. Geeignete Werkstoffvarianten wurden für die Federherstellung ausgewählt. - Gemeinsam mit den Projektpartnern wurden Layoutvarianten für Schraubendruckfedern mit rechteckigem Windungsquerschnitt und für die Federeinbindung in das Sensorsystem erarbeitet. - 4 Federvarianten wurden an der BAM durch Hartbearbeitung von gesinterten Hohlzylindern umgesetzt. Fertigungstoleranzen von < ±10 µm für Windungsbreite, Windungshöhe und Windungsabstand und dünnfilm-kompatible innere Windungsflächen (Ra < 0,2 µm) wurden erreicht. Al2O3- und ZrO2-Federn können rissfrei und mit sehr guter Kantenqualität gefertigt werden, bei Si3N4-Federn konnten Kantenschädigungen nicht vollständig verhindert werden. - Mit der entwickelten Herstellungstechnologie können sowohl „harte“ als auch sehr „weiche“ Federn produziert werden. Federkonstanten zwischen 0,02 N/mm und 10 N/mm wurden realisiert. Die Reproduzierbarkeit der Federfertigung ist gegeben, innerhalb einer Charge unterschieden sich die Federkonstanten der gefertigten Federn nur um etwa +/- 1%. - An einem speziell entwickelten Versuchsstand wurden die Federn unter zyklischer Druckbelastung im Temperaturbereich von -20 bis +80 °C untersucht. An den Al2O3- und ZrO2-Federn wurden keine Schädigungen beobachtet, die Federkonstante wird durch die zyklische Langzeitbelastung nicht verändert. - Die Eignung der keramischen Federn für den Applikationsfall wurde mit zahlreichen Spannungs-Dehnungs-Experimenten, teilweise an speziell aufgebauten Versuchsapparaturen, untersucht. An Al2O3- und Si3N4-Federn wurde – wie erwartet – gefunden, dass die Federkonstante unabhängig von der Belastungsgeschwindigkeit ist und unter konstanter Last auch über lange Zeiträume keine Verformung auftritt. Überraschenderweise zeigten ZrO2 (TZP)-Federn ein zeitabhängiges Verhalten unter Last. Dieses ist besonders stark bei Y-stabilisierten Werkstoffvarianten ausgebildet, wurde aber mit Hochpräzisionsmessungen auch bei Ce-stabilsierten Werkstoffen nachgewiesen. Die Deformation ist reversibel, eine vollständige Relaxation wird erst nach Tagen erreicht. Aufgrund der zeitabhängigen Verformung können ZrO2 (TZP)-Federn, trotz ihrer hervorragenden Festigkeit und Bruchzähigkeit, nicht für die konzipierten Sensorfedern eingesetzt werden. - Das durch die Fa. Siegert TFT entwickelte Metallisierungs-Schichtsystem, bestehend aus aufgesputterten Ti-, Pt- und Au-Schichten verstärkt durch eine galvanisch aufgebrachte Au-Schicht, wurde an der BAM umfassend bewertet. Die Schichten sind untereinander und mit der Keramik weitgehend defektfrei verbunden, die lokale Schichtdicke schwankt jedoch bedingt durch Abschattungseffekte während der Beschichtungsvorgang. Es wurden Schichtwiderstände zwischen 50 und 90 Ohm und damit die Zielvorgabe des Projektes (< 100 Ohm) erreicht. In statischen und dynamischen Belastungstests wurden keine Veränderungen der Leitungswiderstände festgestellt. - Zur Erhöhung der Kapazität des Kondensators kann der Raum zwischen den Federwindungen statt mit Luft mit einer Flüssigkeit mit hoher Dielektrizitätskonstante gefüllt werden. Als geeignete Flüssigkeit wurde Propylencarbonat mit einer Dielektrizitätskonstante von 65, einem hohen Siedepunkt und einer geringen Viskosität identifiziert. Um eine noch höhere Dielektrizitätskonstante zwischen den Federwindungen zu erreichen. wurden Suspensionen aus Silikonöl und nanokristallinem Bariumtitanat hergestellt und bezüglich ihrer Langzeitstabiltät charakterisiert. - Gemäß den Anforderungen des Projektpartners KOMPASS wurden maßgeschneiderte Al2O3-Federn mit einer Federkonstante < 0,1 N/mm hergestellt und für den Aufbau des finalen Demonstrator eingesetzt. Die prinzipielle Funktionsfähigkeit des neuen Sensorkonzeptes auf Basis keramischer Federn wurde mit dem im Projekt aufgebauten Demonstrator nachgewiesen. Die Umsetzung der F+E-ergebnisse in eine industrielle Nutzung zur Herstellung von Gravimetern wird vom Projektpartner KOMPASS angestrebt und ist bereits mit detaillierten Zeitplänen untersetzt. KW - Langzeitstabilität KW - Sensorik KW - Keramikfeder KW - Spannungs-Dehnungs-Verhalten PY - 2019 UR - https://www.gbv.de/dms/tib-ub-hannover/1681417375.pdf UR - https://www.tib.eu/de/suchen/id/TIBKAT%3A1681417375/Alterungsbest%C3%A4ndige-keramische-Federsensoren-durch/ SP - 1 EP - 64 PB - Bundesanstalt für Materialforschung und -prüfung CY - Berlin AN - OPUS4-50742 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Serrano-Munoz, Itziar A1 - Pfretzschner, Beate A1 - Kromm, Arne A1 - Nadammal, Naresh A1 - Kardjilov, N. A1 - Markötter, Henning A1 - Neuwirth, T. A1 - Schulz, M. A1 - Griesche, Axel T1 - High-resolution Bragg-edge neutron radiography detects grain morphology in PBF-LB/M IN718 N2 - One of the main advantages of metal additive manufacturing (MAM) techniques is their ability to produce components with site-specific microstructural features. Nevertheless, microstructural defects and lack of repeatability are still major concerns in MAM. In this study, a laser powder bed fusion (PBF-LB/M) IN718 material, produced using two different scan length vectors, is investigated using Bragg-edge neutron 2D imaging (BENI) combined with electron backscatter diffraction (EBSD) analysis. BENI is able to detect, on a macroscopic scale, process-induced changes in texture in a large field of view covering the entire sample (20×80 mm2). In addition, high-resolution BENI (HR-BENI), with a pixel size of 12.8 µm, provides a micro-scale examination of the local variations of texture and grain morphology, otherwise undistinguishable using the standard resolution. As such, HR-BENI offers a straightforward and detailed way of screening the integrity of MAM parts at cm-length scales. KW - Bragg-edge neutron 2D imaging (BENI) KW - Metal additive manufacturing (MAM) KW - IN718 PBF-LB/M KW - Crystallographic texture control KW - Electron backscatter diffraction (EBSD) PY - 2023 DO - https://doi.org/10.1016/j.mtla.2023.101827 SN - 2589-1529 VL - 30 SP - 1 EP - 6 PB - Elsevier CY - Amsterdam AN - OPUS4-57819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thünemann, Andreas A1 - Kurth, D.G. A1 - Beinhoff, M. A1 - Bienert, Ralf A1 - Schulz, Burkhard T1 - V-Shaped Crystalline Structures of Di-n-alkyl Esters of Phosphoric Acid N2 - We prepared crystals of di-n-alkyl esters of phosphoric acid with chain lengths of n = 10, 12, 14, 16, and 18. These were characterized by single-crystal X-ray analysis and differential scanning calorimetry (DSC). It was found that the alkyl chains are in an extended all-trans conformation and aligned close to perpendicular, forming V-shaped molecules. This is in strong contrast to the typical arrangement of the alkyl chains of phospholipids where the two alkyl chains are arranged parallel in the same direction (e.g., tuning fork configuration in bilayers). Additionally, it was found that the arrangement of the V-shaped molecules of the di-n-alkyl esters in neighboring stacks of the lamellar crystals is antiparallel for short chain lengths (n = 10 and 12) and parallel for the longer (n = 14 and 16). DSC reveals that the melting of the crystals increases systematically with increasing chain lengths from 48 to 82 C. The contribution of each methylene group to the melting enthalpy (70-133 kJ/mol) is independent of the chain length (3.9 kJ per mol CH2). PY - 2006 DO - https://doi.org/10.1021/la0603572 SN - 0743-7463 SN - 1520-5827 VL - 22 IS - 13 SP - 5856 EP - 5861 PB - American Chemical Society CY - Washington, DC AN - OPUS4-12446 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Geburtig, Anja A1 - Schulz, Ulrich A1 - Mechtel, M. A1 - Klimmasch, T. A1 - Klinke, E. T1 - The action of outdoor weathering on the scratch resistance and reflow ability of automotive clearcoats T2 - 7th Nürnberg Congress CY - Nuremberg, Germany DA - 2003-04-07 PY - 2003 SN - 3-87870-146-2 VL - 2 SP - 295 EP - 309 PB - Vincentz CY - Hannover AN - OPUS4-2820 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geburtig, Anja A1 - Schulz, Ulrich A1 - Mechtel, M. A1 - Klimmasch, T. T1 - Reflow ability of automotive coatings T2 - 27th FATIPEC Congress CY - Aix-en-Provence, France DA - 2004-04-19 PY - 2004 VL - 1 SP - 279 EP - 289 PB - Association Francaise des Techniciens des Peintures, Vernis,Encres CY - Aix en Provence AN - OPUS4-21349 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Geburtig, Anja A1 - Schulz, Ulrich A1 - Klimmasch, Th. A1 - Mechtel, M. T1 - The action of weathering on the scratch behaviour of automotive clearcoats KW - Weathering KW - Scratch resistance KW - Reflow ability PY - 2003 SN - 0930-3847 SP - 14 pages PB - Vincentz CY - Hannover AN - OPUS4-2821 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schulz, Ulrich A1 - Geburtig, Anja A1 - Crewdson, M. A1 - Stephenson, J. ED - Reichert, T. T1 - The Southern Florida Acid Rain Test T2 - 2nd European Weathering Symposium - Natural and Artificial Ageing of Polymers CY - Gothenburg, Sweden DA - 2005-06-16 KW - Weathering Reference Materials PY - 2005 SN - 3-9808382-9-3 VL - 6 SP - 49 EP - 62 PB - Gesellschaft für Umweltsimulation CY - Pfinztal AN - OPUS4-10375 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Ralph-Peter A1 - Falkenhagen, Jana A1 - Schulz, Günter A1 - Heinemann, M. T1 - Methodenkopplung zur Polylactidcharakterisierung PY - 2003 SN - 0344-1733 SN - 1610-8256 VL - 27 SP - 56 EP - 57 PB - Vogel CY - Würzburg AN - OPUS4-2597 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krüger, Ralph-Peter A1 - Falkenhagen, Jana A1 - Schulz, Günter A1 - Heinemann, M. A1 - Weinmann, S. A1 - Friedrich, Jörg Florian A1 - Fritz, H.-G. ED - Fritz, H.-G. ED - Eisenbach, C. D. T1 - Synthese von Polylactiden mittels reaktiver Extrusion und Produktcharakterisierung durch Kopplung von HPLC-Methoden mit der MALDI-TOF-MS T2 - 18. Stuttgarter Kunststoff-Kolloquium CY - Stuttgart, Deutschland DA - 2003-03-19 PY - 2003 SN - 3-00-010663-4 IS - CD-ROM PB - Univ., IKT, IAMC CY - Stuttgart AN - OPUS4-2190 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bismarck, A. A1 - Menner, A. A1 - Kumru, M.E. A1 - Sezai Sarac, A. A1 - Bistritz, Martina A1 - Schulz, Eckhard T1 - Poly(carbazole-co-acrylamide) electrocoated carbon fibers and their adhesion behaviour to an epoxy resin matrix N2 - The surface properties of original high strength and preoxidized high modulus carbon fibers were altered by electrocopolymerizing acryl amide and carbazole and therefore depositing a copolymer coating onto the fibers. Scanning electron microscopy and zeta-potential measurements confirmed the presence of a rough but dense and continuous electrocoating with a basic surface character. Therefore, lsquogoodrsquo adhesion behavior between the electrocoated carbon fibers and an epoxy resin matrix should be expected. The interfacial adhesion was measured using the single fiber pull-out and single fiber indentation test. It was shown that only lsquointermediatersquo adhesion was present between the carbon fibers and the electrocoating, but superior adhesion between the coating and epoxy resin exists. The single fiber model composites always failed at the fiber/electrocoating interface. However, as shown by using the indentation test, the interfacial adhesion between fibers and electrocoating can be significantly improved if preoxidized fibers are used as substrate for electropolymerization. A very high tensile strength for the electrocoating can be expected as derived from the single fiber pull-out tests. PY - 2002 DO - https://doi.org/10.1023/A:1013749019958 SN - 0022-2461 SN - 1573-4803 VL - 37 IS - 3 SP - 461 EP - 471 PB - Springer Science + Business Media B.V. CY - Norwell, Mass. AN - OPUS4-6844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Leitner, M.B. A1 - Schinkel, G. A1 - Springer, J. A1 - Ruhmann, R. A1 - Schulz, Günter A1 - Niesel, F.T. T1 - Methacrylate copolymers containing azoanthraquinone units: synthesis by direct copolymerization and by polymer-analogous esterfication reaction PY - 1997 SN - 1381-5148 SN - 1873-166X VL - 33 SP - 137 PB - Elsevier CY - Amsterdam AN - OPUS4-2155 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -