Z Other Special Topics
Refine
Year of publication
- 2019 (17) (remove)
Document Type
- Part of a Book (13)
- Bachelor Thesis (1)
- Conference Proceeding (1)
- Master's Thesis (1)
- Study Thesis (1)
Has Fulltext
- yes (17)
Keywords
- Biogas (2)
- CALB (2)
- Comic (2)
- Esterification (2)
- Lipase (2)
- Nitrification (2)
- On-demand production (2)
- :metabolon (1)
- Acceptor reaction (1)
- Alternansucrase (1)
Neben den großen Anbietern digitaler Comics mit elektronischem Kopierschutz (DRM) haben sich auch Anbieter für DRM-freie Comics etabliert. Als Open Source-Alternative zu den Plattformen Ersterer wurde im Rahmen des Praxisprojekts die Software ComicLib als Web-App zur Verwaltung digitaler Comicsammlungen geschaffen. Diese ermöglicht die gemeinsame Verwaltung DRM-geschützter sowie -freier Comics. Letz-tere sind außerdem im Webbrowser lesbar. Die im Rahmen dieser Arbeit entstandene And-roid-App soll eine Open Source-Alternative zu den mobilen Apps der Plattformen der gro-ßen Anbieter sein und ComicLib um eine mobile App zur Offline-Nutzung der Comics erwei-tern. Der erste Prototyp wird im Nachgang des Projekts weiter getestet und verbessert, be-vor die erste stabile Version veröffentlicht wird.
Entwicklung einer freien Software zur Verwaltung von digitalen Comics auf Basis von Web Technologien
(2019)
Mit dem Aufkommen von E-Books sind auch Comics im digitalen Zeitalter angekommen. Digitale Comicsammlungen bestehen meistens aus Dateien unterschiedlicher, teils proprietärer Dateiformate. Da Comics in proprietären Formaten nur in den Anwendungen der Hersteller geöffnet werden können, gestaltet sich die gemeinsame Verwaltung aller Comics einer Sammlung schwierig. Da die Verwaltung der Comics bei diesen Herstellern zentralisiert auf deren Servern erfolgt, ist das Lesen von Comics bei diesen über deren Apps standortunabhängig möglich. Diesen Vorteil bieten Comics in nicht-proprietären Formaten nicht. Für den maximalen Komfort muss man sich also für einen einzelnen Anbieter entscheiden und eine Fragmentierung der eigenen Comicsammlung über mehrere Anbieter hinweg vermeiden. Diese Probleme soll dieses Projekt lösen und dazu mit ComicLib eine freie Software zur zentralen Verwaltung und Bereitstellung digitaler Comicsammlungen schaffen. Da ein Öffnen der proprietären Dateien nicht möglich ist, soll die Beschaffung von Informationen zu Comics, Serien und Verlagen über den Zugriff auf die ComicVine API1 von Gamespot2 erfolgen. Bei Comics in nicht-proprietären Dateiformaten soll das Lesen direkt in der Software möglich sein, bei den proprietären Formaten soll die Datei stattdessen nur zum Download bereitgestellt werden. Eine eigene Programmierschnittstelle soll die Erweiterung von ComicLib um mobile Apps ermöglichen. Die Implementation als Webanwendung soll eine Nutzung der Comicverwaltung auf Computern, Tablets und Smartphones ermöglichen.
STEPsCON 2018 was jointly organized by the Faculty of Applied Natural Sciences of TH Köln (Germany) and the University of Oulu (Finland) on the occasion of the 50th anniversary of the Leverkusen – Oulu town twinning. The conference focused on sustainability issues and covered the current state of research in four key topics:
1. Sustainable Medicine and Pharmaceuticals
2. Resources and Bioremediation
3. Sustainable Chemistry & Industrial Biotechnology
4. Innovative Materials & Formulations
For use in a landfill, a laboratory reactor for safe and environmentally friendly biological utilization of low-concentration methane gas will be further developed. The current principle of denitrification-coupled aerobic methane oxidation will be replaced by methane oxidation under anaerobic conditions. Anaerobic methane oxidation offers the advantage that, in addition to methane, nitrate also undergoes biodegradation. Another advantage is that the oxygen content can be significantly lower. This reduces the risk of the formation of an explosive atmosphere in the reactor. Currently, the principle of anaerobic methane oxidation is known. However, organisms capable of doing so are not yet available as a pure culture. Therefore, several biomasses were probed for the ability of anaerobic methane oxidation. It was found that moor-heavy sediment, activated sludge from the leachate treatment plant and biomass from the local biogas plant oxidize methane after the natural carbon source (C source) was been removed.
The synthesis of 17-hydroxy-oleic acid based oligomeric esters was investigated with immobilized Pseudozyma antarctica Lipase B and hexanediol as co-substrate. The effects of different reaction parameters on velocity and product composition at equilibrium conditions were analyzed. The synthesis of oleic acid esters was used as a reference system for initial evaluation of reaction parameters. The reaction with oleic acid and hexanediol was fastest at an enzyme concentration of 5% at 60 °C and high conversions of > 90 % were achieved in non-polar solvents in the presence of molecular sieves. In heptane an oleic acid conversion of 96 % was reached with a final diester to monoester ratio of > 4:1. In syntheses trials with 17-hydroxy-oleic acid the formation of oligomers was verified with GPC, however; conversion was generally lower than with oleic acid. Removal of hydroxyl fatty acid monomers and dimers and the formation ester functionalities could be verified by GC analysis. An increase of the degree of oligomerization was observed simultaneously by GPC analysis. The number-average molecular weight was around 1400 in the best trials corresponding to a degree of oligomerization of around 4 units of hydroxyl-fatty acid attached to a hexanediol core. Though transformations were not complete, the final oligomer size was in the lower range of polyester diols used for polyurethane manufacturing.
Due to the worldwide shortage of petrochemical based resources, the usage of renewable bio-based raw materials for established and novel products becomes increasingly important.[1] Such bio-based resources are already used for the fabrication of a variety of products, e. g. paper, lubricants, detergents or cosmetics. In the future they are expected to emerge in many more applications in industry and household.[1]
A very promising approach relies on the use of glycolipids as a source of hydroxy-oleic acid.[2] Microbial glycolipids are produced for instance via fermentation from natural resources such as plant oils and sugar.[3] After fermentation complex product mixtures are obtained with the composition depending on the microorganism, substrate and fermentation time.[3] The successful use of microbial glycolipids and hydroxy-oleic acid (HOA) derived therefrom as bio-based intermediates requires reliable analytical methods as well as robust manufacturing processes for the synthesis and cleavage of bio-based molecules. In order to obtain hydroxy-oleic acids as bio-based intermediates, the acidic cleavage of microbial derived sophorolipid was investigated. In addition the implementation of HOA in polyurethane (PU) systems was explored.
The introduction of Feed-in tariffs in the German Renewable Energy Act (EEG) fuelled the growth of anaerobic digestion (AD) industry making Germany the country with highest number of operational AD plants. However, the rapid expansion of AD industry resulted in some unwanted side-effects such as food vs fuel debate, increased prices for electricity and the temporal mismatch between supply and demand of electricity grid. Subsequent amendments in EEG has tried to address some of these issues by reduction in Feed-in tariffs, introduction of a cap on cereal based feedstocks and providing premium for energy production in accordance with market demand. Furthermore, the Feed-in tariffs which were introduced for 20 years are soon going to expire. The changes in legal and political discourse is soon going to introduce some new challanges to the AD industry. This paper has discussed some of these challanges and their potential solutions.
The electricity network is undergoing a change due to reducing costs for renewable energy sources. Subsidy programs for renewable energy sources are changing and the funding available is being reduced. This will have an impact on anaerobic digestion which in some cases may struggle financially. Overfeeding is one of the most common mechanisms of inhibition in the process, and by shifting to intermittent feeding for on-demand production, this change will provide more information about the digestion process and could be used to detect the beginning of inhibition due to overfeeding. This paper discusses the shift towards intermittent production and how this change can be used to monitor the anaerobic digestion process.
Comparative analysis of non-natural acceptor glucosylation with sucrase enzymes of family GH 70
(2019)
Mutan- and alternansucrase were analyzed for their non-natural glucosylation potential with catecholic compounds caffeic acid and nordihydroguaiaretic acid (NDGA) as well as with non-catecolic p-coumaric acid and umbellic acid. Mutansucrase accepted both catecholic substrates and high glucosylation yields of 92 % with caffeic acid and 81 % with NDGA were obtained. The enzyme showed a clear regio-preference for the catechol 4-OH, which corresponds to findings from our previous work with Leuconostoc and Weissella derived glucansucrases. The substrate spectrum of the alternansucrase was broader and all substrates were successfully glucosylated with a preference for the catechols. Interestingly alternansucrase possessed a different regio-specificity. With caffeic acid the 3-O-α-D-glucoside was the major product. A similar substrate spectrum and regioselectivity pattern was observed in previous glucansucrase screenings only with glucansucrase from strain Weissella beninensis DSM 22752. Therefore it may be concluded that the W. beninensis enzyme is an alternansucrase type enzyme as well.
In the degradation of ammonia (NH4+) to gaseous nitrogen (N2), the nitrification is one of the two reaction steps. The nitrification itself is divided in two steps and is performed by two different types of bacteria. Current literature has shown that there are types of bacteria, which have the genetic equipment to perform both steps in one bacteria. Nevertheless, in wastewater and landfill leachate treatment, ammonia-oxidizing organisms (AOO) and nitrite-oxidizing organisms (NOO) occur as a symbiosis. The intermediate of the two consecutive reaction steps (NO2-, nitrite) is toxic. For this reason, both steps are necessary for the two bacterial groups. To determine the ratio of AOO, NOO and heterotrophic bacteria (which use organic compounds as carbon and energy source) the oxygen uptake rate (OUR) with selective inhibition with N-allylthiourea (ATU) and azide is used. In the inflow of a pilot plant in one street a step by step increased amount of a process water out of a fermentation plant was added to the landfill leachate. For comparison, the other street was supplied only with landfill leachate with the same amount of nitrogen. As a result, comparable values for the different bacterial groups and reproducible results were measured and lead to a better understanding of the analysed nitrification sludge. Deeper understanding of the behavior of the different groups will result in a reduce risk of malfunctions and a more stable operation in the wastewater or landfill leachate treatment plant.