TY - GEN A1 - Hampe, Andreas A1 - Mielke, Werner A1 - Boro, I. T1 - Charakterisierung von Versagensmechanismen an Einzelfaserproben T2 - DKI-Tagung CY - Darmstadt, Deutschland DA - 1988-04-12 PY - 1988 SN - 3-927090-00-X SP - 45 EP - 48 PB - Deutsches Kunststoff-Institut CY - Darmstadt AN - OPUS4-11950 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Hässelbarth, Werner A1 - Golze, Manfred A1 - Noack, Siegfried A1 - Subaric-Leitis, Andreas T1 - Guide to the Evaluation of Measurement Uncertainty for Quantitative Test Results PY - 2006 IS - 1 SP - 1 EP - 49 PB - EUROLAB Technical Secretariat CY - Paris AN - OPUS4-13871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schönhals, Andreas A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schick, C. T1 - Behaviour of polymers confined to nanoporous glasses studied by dielectric, thermal and vibrational spectroscopy - Cut - off length scale for glass transition? T2 - Frühjahrstagung des Arbeitskreises Festkörperphysik bei der DPG CY - Regensburg, Germany DA - 2002-03-11 PY - 2002 SN - 0420-0195 SN - 0372-5448 SN - 0343-9216 IS - CPP 7.2 SP - 428 CY - Bad Honnef AN - OPUS4-2029 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Rose, Peter A1 - Raabe, Peter A1 - Daum, Werner A1 - Szameit, Andreas T1 - Neue Verfahren für die Prüfung von Reaktorkomponenten mittels Röntgen- und Gammastrahlen N2 - Mittels Mehrwinkel-Radiometrie ist es gelungen, berührungslos und automatisch die Tiefenlage von Fehlern zu bestimmen. Das Verfahren ist speziell auf alle durchstrahlbaren Objektgeometrien übertragbar. T3 - BAM Forschungsberichtreihe - 114 KW - Bildverarbeitung KW - Röntgengrobstrukturanalyse KW - Bauelement KW - Kernreaktor PY - 1985 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-3367 SN - 978-3-88314-419-3 SN - 0938-5533 VL - 114 SP - 1 EP - 243 PB - Wirtschaftsverlag NW CY - Bremerhaven AN - OPUS4-336 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin A1 - Wald, Oliver A1 - Turky, Gamal A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schartel, Bernhard A1 - Schönhals, Andreas T1 - Dielectric Relaxation and Gas Transport Properties in Polypropylene Based Nanocomposites T2 - ACS 2002 Biennial Symposium "Polymeric Nanomaterials" CY - Rohnert Park, CA, USA DA - 2002-11-17 PY - 2002 SP - 1(?) EP - 3(?) AN - OPUS4-2035 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böhning, Martin A1 - Tidjani, Adams A1 - Wald, Oliver A1 - Turky, Gamal A1 - Goering, Harald A1 - Brzezinka, Klaus-Werner A1 - Schartel, Bernhard A1 - Schönhals, Andreas T1 - Polypropylene/Clay Nanocomposites - Gas Transport Characteristics and Molecular Mobility T2 - Polydays 2002 CY - Berlin, Germany DA - 2002-09-30 PY - 2002 SP - 1(?) EP - 2(?) AN - OPUS4-2038 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Werner, Steve A1 - Rogge, Andreas T1 - The effect of various fire-exposed surface dimensions on the spalling of concrete specimens N2 - Concrete spalling due to fire exposure is often defined as the sudden detachment of fragments from a concrete surface. It can be quantified by various parameters of which weight loss and spalling depth are the most common ones. The risk of spalling is influenced by many factors such as concrete composition, heating rate and applied testing methods. A reduced scale testing method should be developed to analyse the spalling behaviour and to understand its effectiveness in more detail. As a subsection of this development, this study aimed to analyse the effect of different-sized, circular heated areas in semi full-scale fire tests. Therefore, vermiculite slabs with varying cut-outs in their centre were placed between a specimen made of a spalling-sensitive concrete and the combustion chamber. The combustion chamber was heated following a standard fire curve. Our experimental results show that the thermal expansion inside of equal-sized specimens is strongly dependent on the size of the heated area. In addition, this area also affects thermal stresses. They decrease as a result of lower temperature gradients for tests with smaller unheated boundary areas. Apart from this, the analysis of fragments shows no correlation between their relative volume distribution and the heated area. KW - Concrete spalling KW - High temperature tests KW - Fire exposure area KW - Fragmentation PY - 2015 DO - https://doi.org/10.1002/fam.2256 SN - 0308-0501 SN - 1099-1018 VL - 39 IS - 5 SP - 545 EP - 556 PB - Heyden CY - London AN - OPUS4-34160 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hu, Wei-Hua A1 - Said, Samir A1 - Rohrmann, Rolf A1 - Rücker, Werner A1 - Cunha, A. A1 - Rogge, Andreas ED - De Stefano, A. T1 - Vibration-based structural health monitoring of a highway bridge based on continuous dynamic measurements during 14 years N2 - This paper presents the continuous dynamic measurements of an aging prestressed box-beam bridge during the period from 2000 to 2013, which consists of dynamic properties and environmental/operational factors, as well as the Variation of the extracted health features after removing the environmental/operational effects. Firstly, the variations of frequency estimates, temperatures and traffic loads from 2000 to 2013 are described. Subsequently, correlation analysis between them indicates the nonlinear influences of the temperature on the frequency estimates. The Multiple Linear Regression (MLR) method is used to remove the environmental/operational effects and the health index is proposed by performing the Novelty Detection analysis of the residual errors. Finally, the variations of the health index may indicate clear structural modifications that can be also characterized by the long term monitoring of the dynamic strain in the prestressed cable. T2 - SHMII-7 - 7th International conference on structural health monitoring of intelligent infrastructure CY - Torino, Italy DA - 01.07.2015 KW - Westend bridge PY - 2015 SP - 1 EP - 12 AN - OPUS4-35124 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst A1 - Wiggenhauser, Herbert A1 - Mielentz, Frank A1 - Bertschat, Anja-Sophie A1 - Mierschke, Vivien A1 - Werner, Andreas T1 - Untersuchung von Veränderungen in Beton mit Ultraschall-Codawelleninterferometrie N2 - Die Coda transmittierter Ultraschallsignale in Beton enthält Informationen zu Struktur und Zustand des Materials bzw. deren Änderung. Relevant sind u. a. Temperatur, Stress, Feuchtigkeit und verschiedene Schädigungsmechanismen. Die zahlreichen Einflussfaktoren sind nur schwer zu trennen und die Messeffekte oft zu Beginn sehr klein.Die CWI ermöglicht die Detektion kleinster Geschwindigkeitsveränderungen durch den Vergleich, der in kleinen Schritten gestauchten oder gestreckten Signalen mit eine Referenzmessung. Andere Indikatoren für Änderungen im Material sind: • Kreuzkorrelation • Laufzeit direkte Welle • Energie/Amplitude • Änderungen im Frequenzspektrum Die beschriebene Technik wird von uns bisher primär in klein- und großskaligen Laborversuchen genutzt. Die Forschung konzentriert sich auf die Untersuchung und Trennung verschiedener Einflusseffekte. Aber auch erste reale Bauwerke wurden schon instrumentiert, z. B. Brücken und eine Tunneldecke. T2 - 77. Jahrestagung der Deutschen Geophysikalischen Gesellschaft CY - Potsdam, Germany DA - 27.03.2017 KW - Beton Ultraschall Monitoring PY - 2017 AN - OPUS4-39661 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Böhning, Martin A1 - Tidjani, Adams A1 - Wald, Oliver A1 - Brzezinka, Klaus-Werner A1 - Turky, Gamal A1 - Goering, Harald A1 - Schartel, Bernhard A1 - Schönhals, Andreas T1 - Dielectric and gas transport properties of polypropylene-clay nanocomposites T2 - Frühjahrstagung des Arbeitskreises Festkörperphysik bei der DPG CY - Regensburg, Germany DA - 2002-03-11 PY - 2002 SN - 0420-0195 SN - 0372-5448 SN - 0343-9216 IS - CPP 5.4 SP - 425 CY - Bad Honnef AN - OPUS4-2036 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Rogge, Andreas A1 - Rücker, Werner A1 - Baeßler, Matthias T1 - Tragverhalten und Zustandsbewertung von Offshore-Windenergieanlagen unter hochzyklischer Beanspruchung N2 - Die hochzyklischen Einwirkungen auf Offshore-Windenergieanlagen führen zu bemessungsrelevanten Ermüdungsbeanspruchungen aller Anlagenteile einschließlich der baulichen Konstruktion. Daraus ergeben sich diverse Fragestellungen hinsichtlich der Zuverlässigkeit und Wirtschaftlichkeit dieser Anlagen, die hier beispielhaft am Langzeit-Verformungsverhalten der Gründungskonstruktionen dargestellt sind. Die dynamischen Eigenschaften haben erhebliche Konsequenzen für die konstruktive und betriebstechnische Auslegung der Anlagen. Eine geeignete Möglichkeit sowohl zur Erfassung des Langzeitverhaltens als auch zur Erkennung von Schädigungsvorgängen stellt das Structural Health Monitoring mit unmittelbarer Ergebnisbewertung dar. Ein geeignetes Messsystem und die erforderlichen Auswertungsroutinen wurden im Rahmen eines Forschungsprojektes entwickelt, vergleichend bewertet und im Originalmaßstab erprobt. KW - Gründung KW - Langzeitverhalten KW - Ermüdung KW - Schädigung KW - Monitoring PY - 2012 SN - 1431-5122 N1 - Serientitel: Berichte aus dem konstruktiven Ingenieurbau – Series title: Berichte aus dem konstruktiven Ingenieurbau VL - 12/4 SP - 227 EP - 234 AN - OPUS4-27055 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Orts Gil, Guillermo A1 - Natte, Kishore A1 - Thiermann, Raphael A1 - Girod, Matthias A1 - Rades, Steffi A1 - Kalbe, Henryk A1 - Thünemann, Andreas A1 - Maskos, M. A1 - Österle, Werner T1 - On the role of surface composition and curvature on biointerface formation and colloidal stability of nanoparticles in a protein-rich model system N2 - The need for a better understanding of nanoparticle–protein interactions and the mechanisms governing the resulting colloidal stability has been emphasised in recent years. In the present contribution, the short and long term colloidal stability of silica nanoparticles (SNPs) and silica–poly(ethylene glycol) nanohybrids (Sil–PEG) have been scrutinised in a protein model system. Well-defined silica nanoparticles are rapidly covered by bovine serum albumin (BSA) and form small clusters after 20 min while large agglomerates are detected after 10 h depending on both particle size and nanoparticle–protein ratio. Oppositely, Sil–PEG hybrids present suppressive protein adsorption and enhanced short and long term colloidal stability in protein solution. No critical agglomeration was found for either system in the absence of protein, proving that instability found for SNPs must arise as a consequence of protein adsorption and not to high ionic environment. Analysis of the small angle X-ray scattering (SAXS) structure factor indicates a short-range attractive potential between particles in the silica-BSA system, which is in good agreement with a protein bridging agglomeration mechanism. The results presented here point out the importance of the nanoparticle surface properties on the ability to adsorb proteins and how the induced or depressed adsorption may potentially drive the resulting colloidal stability. KW - Nanoparticles KW - Protein corona KW - Biointerface KW - BSA KW - PEG KW - Colloidal stability PY - 2013 DO - https://doi.org/10.1016/j.colsurfb.2013.02.027 SN - 0927-7765 SN - 1873-4367 VL - 108 SP - 110 EP - 119 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-30100 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - López, J.P. A1 - Kraus, Werner A1 - Reck, Günter A1 - Thünemann, Andreas A1 - Kurth, D.G. T1 - Alternating perpendicular 1-D channels in the supramolecular structure of the copper(II) complex [Cu(pyterpy)2](PF6)2 . CH3OH . 0.5 CH2Cl2 (pyterpy = 4'-(4'''-pyridyl)-2,2':6',2''-terpyridine) KW - 4´-(4´´´-pyridyl)-2,2´:6´2´´-terpyridine KW - Copper complexes KW - Crystal structure KW - Supramolecular chemistry KW - Pi-pi stacking PY - 2005 SN - 1387-7003 VL - 8 SP - 281 EP - 284 PB - Elsevier CY - Amsterdam AN - OPUS4-6301 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schempp, Philipp A1 - Cross, C.E. A1 - Pittner, Andreas A1 - Oder, Gabriele A1 - Neumann, R. S. A1 - Rooch, Heidemarie A1 - Dörfel, Ilona A1 - Österle, Werner A1 - Rethmeier, Michael T1 - Solidification of GTA aluminium weld metal: Part I - Grain morphology dependent upon alloy composition and grain refiner content N2 - The solidification conditions during welding strongly influence the weid metal microstructure and mechanical properties of a weid. In the first part of this study, the grain morphology of gas tungsten arc (GTA) bead-on-plate welds was investigated for the aluminum Alloys 1050A (Al 99.5), 6082 (Al SifMgMn), and 5083 (AI Mg4.5Mn0.7). The experiments revealed that increasing welding speed and alloy content allow the growth of small, equiaxed grains, particularly in the weid center. Furthermore, increasing grain refiner additions led to a Strong reduction of the weid metal mean grain size and hence facilitated the columnar to equiaxed transition (CET). In addition, wavelength dispersive X-ray spectroscopy (WDS) and transmission electron microscopy (TEM) analysis revealed in the weid metal TiB2 particles that were surrounded by Al3Ti. This suggests the duplex nucleation theory for nucleation of aluminum grains in GTA weid metal. KW - Aluminium KW - Gas tungsten arc welding (GTAW) KW - Grain refinement KW - Columnar to equiaxed transition (CET) KW - Epitaxial nucleation KW - Duplex nucleation theory PY - 2014 SN - 0043-2296 SN - 0096-7629 VL - 93 SP - 53-s EP - 59-s PB - American Welding Society CY - New York, NY AN - OPUS4-30413 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -