Werkzeuge zur Bewertung von Kraftwerksbeanspruchungen bei windbedingt gesteigerten Dynamikanforderungen

Zur Umsetzung europäischer Klimaschutzziele werden erneuerbare Energien stark gefördert. Erwartungsgemäß werden zukünftig sehr flexible Kraftwerke zur Ausbalancierung von Einspeisefluktuationen der Erneuerbaren Energien benötigt. Diese Arbeit zeigt eine simulationsbasierte Methode zur Bewertung des Beanspruchungszustands von Kraftwerkskomponenten auf. Dazu wird ein komplexes thermodynamisches Modell eines Steinkohlekraftwerks erstellt. Die vorgestellten Methoden zur Bewertung von Ermüdung und Verschleiß quantifizieren den Zielkonflikt zwischen schonendem und dynamischem Kraftwerksbetrieb.In order to meet Europe's carbon reduction goals, renewable energies are promoted today and in the near future. It is expected that highly flexible powerplants are needed for the compensation of supply fluctuations of the renewables. The present thesis shows a simulation based method to evaluate stress loads of thick-walled plant components. Doing so a complex model of a hard coal fired steam unit is presented and validated. The methods provided for evaluation of fatigue and abrasion quantify the trade-off between a preserving and dynamic operation mode

Discovery of a family of γ-aminobutyrate ureas via rational derepression of a silent bacterial gene cluster

Gaburedins, a family of γ-aminobutyrate (GABA)-derived ureas, have been discovered by deletion of gbnR, an arpA-like putative transcriptional repressor in Streptomyces venezuelae ATCC 10712. Comparison of metabolite profiles in the wild type and mutant strains revealed six metabolites in the mutant that are lacking from the wild type. The structure of gaburedin A was established by HRMS combined with 1- and 2-D NMR spectroscopy and was confirmed by total synthesis. The other metabolites were confirmed as congeners using HRMS, MS/MS and feeding of putative biosynthetic precursors. Two genes, gbnA and gbnB, are proposed to be involved in gaburedin biosynthesis. Consistent with this hypothesis, deletion of gbnB in the gbnR mutant abolished gaburedin production. This is the first report to disclose the discovery of novel natural products via rational deletion of a putative pathway-specific regulatory gene

Seenmorphologie: Erfassung der Qualitätskomponentengruppe Morphologie zur unterstützenden Bewertung sächsischer WRRL-Standgewässer

Im Jahr 2016 wurde bei 11 sächsischen Standgewässern erstmals die Seeuferstruktur erfasst. Im vorliegenden Bericht werden die Ergebnisse dargestellt. Die Arbeiten sind gemäß der Europäischen Wasserrahmenrichtlinie erforderlich, nach der u. a. auch über die Morphologie von Seen zu berichten ist. Für die Untersuchungen wurde ein neues Verfahren angewendet, das im Bericht ausführlich beschrieben wird. Zur Vorbereitung der Untersuchungen wurden Tiefenkarten erstellt, die für weitere Gewässeruntersuchungen genutzt werden können

Regulation of antibiotic production in Actinobacteria: new perspectives from the post-genomic era

The antimicrobial activity of many of their natural products has brought prominence to the Streptomycetaceae, a family of Gram-positive bacteria that inhabit both soil and aquatic sediments. In the natural environment, antimicrobial compounds are likely to limit the growth of competitors, thereby offering a selective advantage to the producer, in particular when nutrients become limited and the developmental programme leading to spores commences. The study of the control of this secondary metabolism continues to offer insights into its integration with a complex lifecycle that takes multiple cues from the environment and primary metabolism. Such information can then be harnessed to devise laboratory screening conditions to discover compounds with new or improved clinical value. Here we provide an update of the review we published in NPR in 2011. Besides providing the essential background, we focus on recent developments in our understanding of the underlying regulatory networks, ecological triggers of natural product biosynthesis, contributions from comparative genomics and approaches to awaken the biosynthesis of otherwise silent or cryptic natural products. In addition, we highlight recent discoveries on the control of antibiotic production in other Actinobacteria, which have gained considerable attention since the start of the genomics revolution. New technologies that have the potential to produce a step change in our understanding of the regulation of secondary metabolism are also described