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On March 13, 1997, INDOT and the Department of Natural Resources signed a memorandum of understanding that exempted specified main-tenance activities from the Flood Control and Navigable Waterways Act. There has been much confusion and many interpretation variances in the interim. INDOT has been working with the DNR to update the MOU to provide clarity to areas of conflicting interpretation. Join us for a discussion.

A paradigm for active constituents in (homogeneous) catalysis is that optimum performance requires maximum dispersion. Generally, aggregation results in a decline. This is a different case in supramolecular catalysis. A new concept based on surfactants equipped with functional heads is presented, which becomes a more active catalyst itself upon aggregation. The head group of the surfactants is composed of a diethylenetriamine-functionalized fullerene capable of coordinating to catalytically active metals like CoII. The improvement of catalytic properties upon aggregation is demonstrated via electrocatalytic water-splitting reaction as a model system. Detailed electrochemistry studies were performed at concentrations below and above the critical aggregation concentration (cac). While isolated surfactant molecules represent only moderately active catalysts, drastic improvement of efficiency in the hydrogen evolution (HER) as well as in the oxygen evolution reactions (OER) were detected, once vesicular structures have formed. Self-organization of the surfactants leads to an increase in turnover frequencies of up to 1300 % (HER). The strongly beneficial effect of aggregation arises from the favorable alignment of individual molecules, thus, facilitating intermolecular charge transfer processes in the vesicles. © 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Der Anteil erneuerbarer Energien (EE) an der Energieversorgung in Deutschland wächst kontinuierlich und soll bis zum Jahr 2050 mindestens 60 % am Endenergiebedarf decken. Im Stromsektor stellen die Netze einen Flaschenhals für die Energiewende dar. Das Vorhaben fragt nach den ökonomischen, technischen, rechtlichen, administrativen und gesellschaftlichen Restriktionen, die es für die Integration erneuerbarer Energien nicht nur im Stromsektor, sondern auch in Gas- und Wärmenetzen zu überwinden gilt. Ziel ist es, das Problemfeld der Integration erneuerbarer Energien in den drei Versorgungssektoren in einer Gesamtschau zu strukturieren, offene Forschungsfragen zu verdeutlichen und Ansatzpunkte zur Überwindung der Restriktionen zu liefern. Mit Hilfe von Konstellationsanalysen wird der komplexe Untersuchungsgegenstand strukturiert; sie fassen das Ergebnis der Analyse grafisch zusammen. Ausgangspunkt der Analyse sind die notwendigen Ausbau- und Modernisierungsmaßnahmen an den technischen Infrastrukturen, d. h. den Transportleitungen und ihren Nebenanlagen sowie die zur Aufrechterhaltung der Versorgungssicherheit notwendige Steuerung. Die größten Herausforderungen stellen sich bei der Integration hoher EE-Anteile in das Stromnetz. Auch wenn in der Gas- und Wärmeversorgung kein vergleichbarer Integrationsdruck besteht, sind diese beiden Anwendungsbereiche für erneuerbare Energien nicht zuletzt wegen der sich abzeichnenden Schnittstellen zwischen den Sektoren von Bedeutung. Das Vorhaben zeigt die zunehmenden Interdependenzen zwischen Erzeugung, Transport und Speicherung auf und erfasst auch die zukünftigen Schnittstellen zwischen den Sektoren. Indem zersplittertes Wissen zusammengeführt und transparent gemacht wird, verbessern sich die Voraussetzungen für zukünftige Steuerungsentscheidungen. Online-Version, im Universitätsverlag der TU Berlin (www.univerlag.tu-berlin.de) erschienen The share of renewable energy in the German energy supply is growing steadily. It is expected to contribute at least 60 % to the final energy demand by 2050. In the electricity sector, the power grids constitute a bottleneck for the energy transition. The project explores the economic, technical, legal, administrative and social impediments that have to be resolved in order to integrate renewable energy not only in the electricity grids but into the gas distribution systems and district heating networks as well. The aim is to structure the problem area from a holistic perspective, to clarify open research questions and to provide starting points to overcome these impediments. The methodology of constellation analysis, an interdisciplinary bridging concept, was applied to structure the complex object of investigation and to summarize the findings graphically in constellations. Starting point of the analysis is the need for expansion and modernization of the technical infrastructure, comprising the transmission lines, its ancillary facilities and the control systems to safeguard voltage stability and security of supply. The integration of high shares of renewable energy into the electricity grid poses the biggest challenge amongst the three sectors. Even though the pressure for integrating renewable energy is lower in the gas and district heating supply, these areas assume increasing significance not least due to the apparent need for future interlinkages between the supply sectors. Besides outlining the growing interdependencies between energy generation, transport, and storage, the project also covers the future interconnections between sectors. Consolidating the fragmented knowledge and enhancing its transparency will improve the preconditions for future political steering decisions. Online-Version, published by Universitätsverlag der TU Berlin (www.univerlag.tu-berlin.de)