TY - JOUR A1 - Albrecht, S. A1 - Schäfer, S. A1 - Lange, I. A1 - Yilmaz, S. A1 - Dumsch, I. A1 - Allard, S. A1 - Scherf, U. A1 - Hertwig, Andreas A1 - Neher, D. T1 - Light management in PCPDTBT:PC70BM solar cells: A comparison of standard and inverted device structures N2 - We compare standard and inverted bulk heterojunction solar cells composed of PCPDTBT:PC70BM blends. Inverted devices comprising 100 nm thick active layers exhibited short circuit currents of 15 mA/cm², 10% larger than in corresponding standard devices. Modeling of the optical field distribution in the different device stacks proved that this enhancement originates from an increased absorption of incident light in the active layer. Internal quantum efficiencies (IQEs) were obtained from the direct comparison of experimentally derived and modeled currents for different layer thicknesses, yielding IQEs of ~70% for a layer thickness of 100 nm. Simulations predict a significant increase of the light harvesting efficiency upon increasing the layer thickness to 270 nm. However, a continuous deterioration of the photovoltaic properties with layer thickness was measured for both device architectures, attributed to incomplete charge extraction. On the other hand, our optical modeling suggests that inverted devices based on PCPDTBT should be able to deliver high power conversion efficiencies (PCEs) of more than 7% provided that recombination losses can be reduced. KW - Organic solar cells KW - Inverted solar cells KW - PCPDTBT KW - Low band-gap KW - Optical modeling PY - 2012 DO - https://doi.org/10.1016/j.orgel.2011.12.019 SN - 1566-1199 VL - 13 IS - 4 SP - 615 EP - 622 CY - Amsterdam [u.a.] AN - OPUS4-25453 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pott, U. A1 - Crasselt, Claudia A1 - Fobbe, N. A1 - Haist, M. A1 - Heinemann, M. A1 - Hellmann, S. A1 - Ivanov, D. A1 - Jakob, C. A1 - Jansen, D. A1 - Lei, L. A1 - Li, R. A1 - Link, J. A1 - Lowke, D. A1 - Mechtcherine, V. A1 - Neubauer, J. A1 - Nicia, D. A1 - Plank, J. A1 - Reißig, S. A1 - Schäfer, T. A1 - Schilde, C. A1 - Schmidt, Wolfram A1 - Schröfl, C. A1 - Sowoidnich, T. A1 - Strybny, B. A1 - Ukrainczyk, N. A1 - Wolf, J. A1 - Xiao, P. A1 - Stephan, D. T1 - Characterization data of reference materials used for phase II of the priority program DFG SPP 2005 “Opus Fluidum Futurum –Rheology of reactive, multiscale, multiphase construction materials” N2 - A thorough characterization of base materials is the prereq- uisite for further research. In this paper, the characterization data of the reference materials (CEM I 42.5 R, limestone pow- der, calcined clay and a mixture of these three components) used in the second funding phase of the priority program 2005 of the German Research Foundation (DFG SPP 2005) are presented under the aspects of chemical and min- eralogical composition as well as physical and chemical properties. The data were collected based on tests performed by up to eleven research groups involved in this cooperative program. KW - Portland cement KW - Limestone powder KW - Calcined clay KW - Sustainable cement KW - DFG SPP 2005 PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-569913 DO - https://doi.org/10.1016/j.dib.2023.108902 VL - 47 SP - 1 EP - 19 PB - Elsevier AN - OPUS4-56991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Block, S. A1 - Boß, K.-H. A1 - Frobese, D.-H. A1 - Pape, H. A1 - Gösslinghoff, L. A1 - Grossepieper, T. A1 - Kasper, R. A1 - Kirchner, W. A1 - Kollmann, P. A1 - Kröger, P. A1 - Ringlstetter, P. A1 - Kuska, T. A1 - Mattejat, K. A1 - Niehüser, H. A1 - Pfeiffer, F. A1 - Pötzsch, Klaus-Michael A1 - Jochems, Frank A1 - Schäfer, H. A1 - Vogt, W. A1 - Zankl, C. A1 - Ludzay, J. T1 - Empfehlungen zur Vermeidung von Überdrücken an Tankfahrzeugen bei Untenbefüllung KW - Untenbefüllung KW - Tankfahrzeuge KW - Überdruck KW - Mineralöl KW - Sicherheitsventile PY - 2012 VL - 727 IS - 3 SP - 1-4, Anl. 1-3 AN - OPUS4-27921 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bahlmann, Stefanie A1 - Rübner, Katrin A1 - Meng, Birgit A1 - Hauer, B. A1 - Klein, H. A1 - Müller, C. A1 - Ruppert, J. A1 - Schäfer, S. A1 - Spanka, G. A1 - Wassing, W. A1 - Zunzer, U. T1 - Potenziale des Sekundärstoffeinsatzes im Betonbau - Teilprojekt B1 KW - Nachhaltigkeit KW - Sekundäre Gesteinskörnung KW - Rezyklierte Gesteinskörnung KW - Betonbrechsand KW - Müllverbrennungsasche PY - 2007 SN - 978-3-410-65772-9 SN - 0171-7197 N1 - Geburtsname von Bahlmann, Stefanie: Ramolla, S. - Birth name of Bahlmann, Stefanie: Ramolla, S. IS - 572 SP - 131 EP - 222 PB - Beuth AN - OPUS4-16361 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hauer, B. A1 - Rübner, Katrin A1 - Herbst, Tristan A1 - Schäfer, S. A1 - Seidel, M. T1 - B - Potentials for the use of secondary materials in concrete construction / B - Potenziale des Sekundärstoffeinsatzes im Betonbau KW - Nachhaltig mit Beton bauen KW - Einsatzpotenziale Sekundärrohstoffe KW - Müllverbrennungsaschen KW - Brechsande PY - 2010 SN - 0373-4331 SN - 1865-6528 N1 - Sprachen: Deutsch/Englisch - Languages: German/English VL - 76 IS - 02 SP - 18 EP - 19 PB - Bauverl. CY - Gütersloh AN - OPUS4-21463 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schäfer, N. A1 - Wilkinson, A. J. A1 - Schmid, Thomas A1 - Winkelmann, Aimo A1 - Chahine, G. A. A1 - Schülli, T. U. A1 - Rissom, T. A1 - Marquardt, J. A1 - Schorr, S. A1 - Abou-Ras, D. T1 - Microstrain distribution mapping on CuInSe2 thin films by means of electron backscatter diffraction, X-ray diffraction, and Raman microspectroscopy N2 - The investigation of the microstructure in functional, polycrystalline thin films is an important contribution to the enhanced understanding of structure–property relationships in corresponding devices. Linear and planar defects within individual grains may affect substantially the performance of the device. These defects are closely related to strain distributions. The present work compares electron and X-ray diffraction as well as Raman microspectroscopy, which provide access to microstrain distributions within individual grains. CuInSe₂ thin films or solar cells are used as a modelsystem. High-resolution electron backscatter diffraction and X-ray microdiffraction as well as Ramanmicrospectroscopy were applied for this comparison. Consistently, microstrain values were determined of the order of 10⁻⁴ by these three techniques. However,only electron backscatter diffraction, X-ray microdiffraction exhibit sensitivities appropriate for mapping local strain changes at the submicrometer level within individual grains in polycrystalline materials. KW - Microstrain KW - Thin film KW - X-ray microdiffraction KW - EBSD KW - Raman microspectroscopy PY - 2016 DO - https://doi.org/10.1016/j.ultramic.2016.07.001 SN - 0304-3991 SN - 1879-2723 VL - 169 SP - 89 EP - 97 PB - Elsevier B.V. AN - OPUS4-37453 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmid, Thomas A1 - Schäfer, N. A1 - Levcenko, S. A1 - Rissom, T. A1 - Abou-Ras, D. T1 - Orientation-distribution mapping of polycrystalline materials by Raman microspectroscopy N2 - Raman microspectroscopy provides the means to obtain local orientations on polycrystalline materials at the submicrometer level. The present work demonstrates how orientation-distribution maps composed of Raman intensity distributions can be acquired on large areas of several hundreds of square micrometers. A polycrystalline CuInSe2 thin film was used as a model system. The orientation distributions are evidenced by corresponding measurements using electron backscatter diffraction (EBSD) on the same identical specimen positions. The quantitative, local orientation information obtained by means of EBSD was used to calculate the theoretical Raman intensities for specific grain orientations, which agree well with the experimental values. The presented approach establishes new horizons for Raman microspectroscopy as a tool for quantitative, microstructural analysis at submicrometer resolution. PY - 2015 DO - https://doi.org/10.1038/srep18410 SN - 2045-2322 VL - 5 SP - Article 18410, 1 EP - 7 PB - Nature Publishing Group CY - London AN - OPUS4-35224 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tyagi, R. A1 - Malhotra, S. A1 - Thünemann, Andreas A1 - Sedighi, A. A1 - Weber, M. A1 - Schäfer, A. A1 - Haag, R. T1 - Investigations of host-guest interactions with shape-persistent nonionic dendritic micelles N2 - The interaction of self-assembled dendritic amphiphiles with drugs and dyes in aqueous solutions is of great significance for designing and optimizing shape-persistent delivery systems. Here we present deeper insight for two examples of low molecular weight (LMW) nonionic dendritic amphiphiles as host molecules and a series of selected aromatic guest model molecules (benzene, naphthalene, biphenyl, terphenyl, anthracene, and pyrene). Aromatic guest molecules were incorporated into the self-assemblies of dendritic nanocarriers, and the resultant complexes were studied by a combination of UV, NMR, computational simulation, and small-angle X-ray-scattering (SAXS) techniques in order to determine the loading capacity, localization, and specific interactions in dendritic amphiphiles with guest molecules. Our findings revealed that the localization of guest molecules in the hydrophobic region and the loading capacity of guest molecules are dependent on their size and the arrangement of aromatic rings instead of the loading amount. Furthermore, the shape of self-assembled host molecules was found to be ellipsoidal and highly persistent even after loading the guest molecules. To the best of our knowledge, this is the first systematic host–guest study, particularly with low molecular weight nonionic dendritic amphiphilies and aromatic guest molecules. Thus, this study opens new possibilities and ways to explore the transport behavior of aromatic drugs with such nanocarriers. KW - Nanotechnology PY - 2013 DO - https://doi.org/10.1021/jp401503y SN - 1932-7447 SN - 1089-5639 VL - 117 IS - 23 SP - 12307 EP - 12317 PB - Soc. CY - Washington, DC AN - OPUS4-28710 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Hauer, B. A1 - Pierkes, R. A1 - Schäfer, S. A1 - Seidel, M. A1 - Herbst, Tristan A1 - Rübner, Katrin A1 - Meng, Birgit T1 - Verbundforschungsvorhaben 'Nachhaltig Bauen mit Beton' - Potenziale des Sekundärstoffeinsatzes im Betonbau - Teilprojekt B N2 - Die Nutzung und Weiterverarbeitung von Sekundärstoffen kann in der Baustoffherstellung einen Beitrag zum nachhaltigen Bauen leisten. Im Rahmen des Teilprojekts B wurde die Bewertung dieser Potenziale anhand von Beispielen ausgebaut und verifiziert. Die Basis dieser Bewertungsgrundlage ist die Erfüllung der grundlegenden technischen Anforderungen (ökobilanzielle Indikatoren, vergleichende ökobilanzielle Betrachtung). Im Teilprojekt E geht es um die Freisetzung umweltrelevanter Stoffe aus zementgebundenen Baustoffen. Überprüft werden sollte die Übereinstimmung zwischen Laborergebnissen, Modellierungen und realen Grundwasserkonzentrationen. Es wurden Schlitzwände errichtet, die in den Grundwasserleiter einbinden und umweltrelevante Parameter bestimmt. Grundsätzlich hat sich selbst bei Großbaustellen nur eine geringe Beeinflussung der Grundwasserqualität durch Beton ergeben. KW - Sekundärstoff KW - Zement KW - Beton KW - Nachhaltigkeit KW - Bewertung KW - Recycling KW - Betonbrechsand KW - Müllverbrennungsasche KW - Kesselsand KW - Ökobilanz PY - 2011 SN - 978-3-410-65094-2 SN - 0171-7197 IS - 584 SP - 1 EP - 151 PB - Beuth CY - Berlin AN - OPUS4-25982 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bawadkji, O. A1 - Cherri, M. A1 - Schäfer, A. A1 - Herziger, S. A1 - Nickl, Philip A1 - Achazi, K. A1 - Donskyi, Ievgen A1 - Adeli, M. A1 - Haag, R. T1 - One-pot covalent functionalization of 2D black phosphorus by anionic ring opening polymerization N2 - In this work, a one-pot approach for the covalent functionalization of few-layer black phosphorus (BP) by anionic ring opening polymerization of glycidol to obtain multifunctional BP-polyglycerol (BP-PG) with high amphiphilicity for near-infrared-responsive drug delivery and biocompatibility is reported. Straightforward synthesis in combination with exceptional biological and physicochemical properties designates functionalized BP-PG as a promising candidate for a broad range of biomedical applications. KW - 2D nanomaterial KW - Amphiphilicity KW - Black phosphorus KW - Hyperbranched KW - Polyglycerol KW - Water dispersibility PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-568833 DO - https://doi.org/10.1002/admi.202201245 SN - 2196-7350 VL - 9 SP - 1 EP - 8 PB - Wiley-VCH CY - Weinheim AN - OPUS4-56883 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -