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Eine verbesserte Zusammenarbeit und Abstimmung von Fachwissenschaft, Fachdidaktik, Bildungswissenschaften und schulpraktischen Lernorten ist einer der Förderbereiche der „Qualitätsoffensive Lehrerbildung“. Zahlreiche der geförderten Projekte haben für dieses Handlungsfeld im Bereich Vernetzung von Fachwissenschaft, Fachdidaktik und Bildungswissenschaften hochschulspezifische Maßnahmen konzipiert und umgesetzt.
Der vorliegende Tagungsband beinhaltet Beiträge von 15 entsprechenden Projekten, von denen sieben anlässlich von zwei standortübergreifenden Projekt-Tagungen in Hannover und Potsdam vorgestellt und in Workshops diskutiert wurden. Insgesamt geben die Beiträge einen theoretisch fundierten und gleichzeitig praxisorientierten Überblick über aktuelle Ansätze und Konzepte zur besseren Vernetzung fachwissenschaftlicher, fachdidaktischer und bildungswissenschaftlicher Studienanteile im Lehramtsstudium. Dargestellt werden Projektarbeiten der Hochschulen, die auf verschiedenen Ebenen wirksam werden (curricular-inhaltliche Ebene, kollegiale Ebene, hochschul-strukturelle Ebene). Die Maßnahmen sind so beschrieben, dass sie als Grundlage für einen Transfer auf andere Fächer bzw. andere Standorte genutzt werden können.
Die Beiträge richten sich an alle Lehrenden im Bereich der Lehramtsbildung sowie sonstige Akteure im Bereich der Lehr- und Qualitätsentwicklung an den Universitäten. Sie alle können den beschriebenen Konzepten und Umsetzungsformaten transferierbare Ideen und Impulse entnehmen.
Microporous nitrogen-rich carbon fibers (HAT-CNFs) are produced by electrospinning a mixture of hexaazatriphenylene-hexacarbonitrile (HAT-CN) and polyvinylpyrrolidone and subsequent thermal condensation. Bonding motives, electronic structure, content of nitrogen heteroatoms, porosity, and degree of carbon stacking can be controlled by the condensation temperature due to the use of the HAT-CN with predefined nitrogen binding motives. The HAT-CNFs show remarkable reversible capacities (395 mAh g(-1) at 0.1 A g(-1)) and rate capabilities (106 mAh g(-1) at 10 A g(-1)) as an anode material for sodium storage, resulting from the abundant heteroatoms, enhanced electrical conductivity, and rapid charge carrier transport in the nanoporous structure of the 1D fibers. HAT-CNFs also serve as a series of model compounds for the investigation of the contribution of sodium storage by intercalation and reversible binding on nitrogen sites at different rates. There is an increasing contribution of intercalation to the charge storage with increasing condensation temperature which becomes less active at high rates. A hybrid sodium-ion capacitor full cell combining HAT-CNF as the anode and salt-templated porous carbon as the cathode provides remarkable performance in the voltage range of 0.5-4.0 V (95 Wh kg(-1) at 0.19 kW kg(-1) and 18 Wh kg(-1) at 13 kW kg(-1)).
A Paleoarchean impact spherule-bearing interval of the 763 m long International Continental Scientific Drilling Program (ICDP) drill core BARB5 from the lower Mapepe Formation of the Fig Tree Group, Barberton Mountain Land (South Africa) was investigated using nondestructive analytical techniques. The results of visual observation, infrared (IR) spectroscopic imaging, and micro-X-ray fluorescence (lXRF) of drill cores are presented. Petrographic and sedimentary features, as well as major and trace element compositions of lithologies from the micrometer to kilometer-scale, assisted in the localization and characterization of eight spherule-bearing intervals between 512.6 and 510.5 m depth. The spherule layers occur in a strongly deformed section between 517 and 503 m, and the rocks in the core above and below are clearly less disturbed. The lXRF element maps show that spherule layers have similar petrographic and geochemical characteristics but differences in (1) sorting of two types of spherules and (2) occurrence of primary minerals (Ni-Cr spinel and zircon). We favor a single impact scenario followed by postimpact reworking, and subsequent alteration. The spherule layers are Al2O3-rich and can be distinguished from the Al2O3-poor marine sediments by distinct Al-OH absorption features in the short wave infrared (SWIR) region of the electromagnetic spectrum. Infrared images can cover tens to hundreds of square meters of lithologies and, thus, may be used to search for Al-OH-rich spherule layers in Al2O3-poor sediments, such as Eoarchean metasediments, where the textural characteristics of the spherule layers are obscured by metamorphism.
The long-term persistence of populations and species depends on the successful recruitment of individuals. The generative recruitment of plants may be limited by a lack of suitable germination and establishment conditions. Establishment limitation may especially be caused by the competitive effect of surrounding dense vegetation, which is believed to restrict the recruitment success of many plant species to small open patches ('safe sites'). We conducted experiments to clarify the roles of germination and seedling establishment as limiting processes in the recruitment of Juncus atratus Krock., a rare and threatened herbaceous perennial river corridor plant in Central Europe. Light intensity had a positive effect on germination. However, some seedlings emerged even in total darkness and the germination rate at 1% light intensity was more than half of that at 60% light intensity. Seedling establishment in the field after 10 weeks was 30% on bare ground, but it was close to zero in grassland. Establishment in the growth chamber after 8 weeks was close to 75% for seedlings that germinated underwater, but only about 35% for seedlings that germinated afloat. Furthermore, establishment decreased with flooding duration on bare ground, but increased with flooding duration in grassland. These data indicate that establishment, rather than germination, is a critical life stage in Central European populations off. atratus. They furthermore indicate that the competition of surrounding vegetation for water limits seedling establishment under field conditions without flooding, largely restricting establishment success to bare ground habitats. In contrast, grassland is more suitable for the recruitment off. atratus than bare ground under prolonged flooding. Grassland may facilitate the establishment off. atratus seedlings during long- lasting floods by supplying oxygen to the soil through aerenchyma. The shift from competition to facilitation in grassland occurred after 30 days of flooding, i.e. within the ontogeny of individual plants. The specific recruitment requirements off. arrows may be a main cause of its rarity in modern Central Europe. In order to prevent regional extinction off. atratus, we suggest maintaining or re-establishing natural hydrodynamics in the species' habitats.