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Ziel dieser Arbeit war die systematische Untersuchung diverser Sorbentien für die Beurteilung der Reinigung wasserstoffhaltiger und biogener Gase. Zu diesem Zweck wurde eine volumetrische Multiprobenapparatur entwickelt und aufgebaut. Mit diesem Instrument erfolgte ein breit angelegtes Screening verschiedener Stoffsysteme. In diesem Zusammenhang wurde die Sorption von \(CO_{2}\), \(CH_{4}\), \(N_{2}\) und \(H_{2}\) sowohl an technisch etablierten Sorbentien (Aktivkohlen und Molekularsiebe) wie auch an den neuartigen Substanzklassen der metallorganischen Gerüstwerkstoffen und der ionischen Flüssigkeiten untersucht. Auf dieser Basis erfolgten im Anschluss hochgenaue Sorptionsmessungen an ausgewählten Sorbentien mithilfe einer Magnetschwebewaage. Für die bessere Abbildung realer technischer Prozesse wurden zudem Gemischmessungen an einem multinären Modellgemisch durchgeführt.

This article presents experimental results of thermal conductivity in metal foams. The thermal conductivity of cellular solids differs from those of their corresponding dense material. Therefore, the various pore size level effects contributing to the thermal conductivity are comprised by introducing an effective thermal conductivity. In this work we investigated metallic foams with a porosity ranging from 0.65 to 0.82 manufactured by the Slip Reaction Foam Sintering (SRFS) Process using a nickel-based powder. For the determination of the effective thermal conductivity at room temperature, we employed the Transient Plane Source Technique also known as Hot Disk. We verified the influence of the porosity and the thermal conductivity of the solid phase on the effective conductivity and compared the measured values of the effective conductivity with theoretical ones calculated using the thermal conductivity of the solid phase and the solid volume fraction. We present here a simple model that demonstrates the influence of the geometry of the grid elements qualitatively, discuss the applicability of the method to heterogeneous materials such as metallic foams and give an outlook about further investigations at higher temperatures.

The main goal of TERENO was to create observation platforms on the basis of an interdisciplinary and long‐term aimed research program. By the aid of SoilCan‐lysimeters, an ideal network was built between the four different TERENO‐observatories with their highly instrumented test sites. Within the four TERENO‐observatories at 13 different experimental sites, in total 126 lysimeters were filled monolithically and the measurements were started in October 2010. The lysimeters have been cultivated as grassland or arable land with a standardized crop rotation: winter wheat – winter barley – winter rye – oat.

The present thesis deals with the development of tailor-made ruthenium catalysts for the selective conversion of carboxylic acids, esters and amides, based on the [Ru(Triphos)TMM] catalyst lead structure (TMM = trimethylenemethane, Triphos = 1,1,1-tris(diphenylphosphinomethyl)ethan).Chapter 1 describes the state-of-the-art in hydrogenation with molecular catalysts and the importance of catalytic reduction as a tool for the chemical transformation of polar bonds in laboratory as well as in industrial scale. The [Ru(Triphos)TMM] complex is a universal catalyst for the catalytic conversion of carboxylic acid derivatives, for the di-rect hydrogenation of CO2 to methanol, as well as for the direct methylation of aromatic amines using CO2 as a C1 building block. However, mechanistic investigations revealed that the catalyst deactivates irreversibly by forming an inactive ruthenium dimer in all catalytic transformations, thus preventing a general applicability.In order to prevent the catalyst from deactivating via dimerization, the ligand was chemically modified as described in chapter 2. The dimer formation should be blocked by the introduction of sterically demanding substituents to the aromatic backbone of the ligand, for this reason, a library of 7 triphos derivatives and their corresponding ruthenium complexes could be established. The molecular structures from single-crystal x-ray diffraction of the complexes emphasized that the meta-substituents of the newly developed Triphos Xyl (1,1,1-tris(3,5-dimethylphenylphosphinomethyl)ethan) showed a significantly increased shielding of the ruthenium center in comparison to the usual triphos ligand, paving the way for application in challenging reductive transfor-mations. Chapter 3 contains the detailed mechanistic characterization of the different catalyst species. The activation of [Ru(Triphos)TMM] in the presence of hydrogen leads to the formation of the hydride complex [Ru(Triphos)(H)2], the cationic complex [Ru(Triphos)(H)(H2)][NTf2] is formed in the presence of HNTf2. Moreover, the XRD-analysis of a ruthenium dimer showed that the meta-substituents of the Triphos Xyl ligand should have a major influence on the dimer formation. In selected catalytic reactions (chapter 4) the novel catalyst demonstrated remarkable activities in the hydrogenation of carboxylic acids, esters and amides. Moreover, it was shown by NMR-analysis that the dimer formation was completely prevented in a cata-lytic reaction by the introduction of the Triphos-Xyl ligand. Thus, the Triphos-Xyl ligand significantly improves the chemical stability, catalytic activity and selectivity in the hydrogenation of dimethyl itaconate, itaconic acid and N-acetanilide.

This thesis aims to study the European research opportunity of the Deutsches Zentrum für Luft und Raumfahrt’s (DLR) Facility of Laboratories for Sustainable Habitation (FLaSH) project. FLaSH’s main goal is to research, develop and test Life Support Systems (LSS) technologies for materially closedloop environments, for space and terrestrial application. The core element of the FLaSH is the Habitation Module Complex (HMC), which integrates 12 interconnected modules, each one of them addressing a LSS’s domain in order to achieve a self-reliant habitat: Air, Water, Waste, Greenhouse, Food, Animal, Living, Sickbay, In Situ Resource Utilization (ISRU), Workshop and Energy. As a first step, the literature on LSS and the most relevant infrastructures dedicated to LSS development were reviewed. Successively, FLaSH’s preliminary study conducted in 2012 at the DLR’s Concurrent Engineering Facility (CEF) was analysed. The review on the LSS and FLaSH allowed for the identification of 110 candidate technologies. Finally, a survey was carried out on 172 European entities, identified as potential participants, in order to generate primary data for the FLaSH’s research opportunity study. The survey collected a total of 36 valid responses. Survey respondents revealed that 27 entities, from 15 European countries manifested a potential interest in participation and cooperation with FLaSH. The Air, Water, Waste, Greenhouse modules were identified as the most interesting. Participants’ preferred methods of collaboration comprised technology testing and development as well as advisory services. The majority of the participants, 26, backboned FLaSH’s dual approach of developing closed technologies for space and terrestrial applications.

Die Akzeptanz kleinräumiger Angebote der Lebensmittelversorgung im Untersuchungsraum Stuttgart steht im Mittelpunkt dieses Arbeitsberichts, der grundsätzliche Überlegungen und aktuelle empirische Untersuchungen am Fachgebiet Agrarmärkte und Agrarmarketing der Universität Hohenheim hierzu bündelt. Betrachtet werden die Akteure Verbraucher und Unternehmen in Stuttgart gleichermaßen. Die zentralen Fragen der Untersuchungen lauten: Was bedeuten einer Stadtbevölkerung Lebensmittel regionaler Herkunft? Wie werden kleinräumige Angebote der Lebensmittelversorgung von den urbanen Verbrauchern im Untersuchungsraum Stuttgart angenommen und welche Bedeutung können diese in Zukunft gewinnen? Welche Bedeutung haben Lebensmittel regionaler Herkunft für Händler und Direktvermarkter in Stuttgart und welche Entwicklungen lassen sich ableiten? ; The working paper analyzes the acceptance of short-chain food supply systems by consumers and companies in Stuttgart, the provincial capital of Baden-Württemberg, based on theoretical considerations and empirical studies carried out by the Chair of Agricultural Markets and Marketing at the University of Hohenheim. The key questions of the empirical studies focus on the following points: How does the city population reflect the importance of regional foods? What are the attitudes and purchase behavior of urban consumers in regard to regional food or self production and what importance can the subjects gain in the future? Of which importance is regional food to local merchants? assortment in Stuttgart and which future developments can we derive?

Against the backdrop of the irreversible and systematic destruction of ecosystems, necessary for the survival and quality of life of people and non-human species, caused by human agency and socio-economic structures, we explore the opportunities and challenges to resist ecocide in relation to socio-economic inequality and the crisis of democracy. To this end, first section focuses on the diagnosis of ecocide. We show that due to three fallacies the connection between ecocide, socio-economic inequality and the crisis of democracy is not sufficiently accentuated. In the second section, several contemporary political measures to deal with ecocide are critically examined. We will argue that Agenda 2030, the Sustainable Development Goals, is part of the problem as it falsely assumes the compatibility of sustainability and economic growth. Finally, in the third section, the opportunities and challenges of resistance to ecocide are discussed with an emphasis on the power asymmetries between the Global North (GN) and the GS.