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The present thesis investigates the thermodynamic and kinetic processes associated with gas sorption (CO2, CH4) on coal. It is incorporated into a research field which studies CO2-sequestration in combination with CO2-enhanced coalbed methane production in unminable coal seams. This combination is regarded as a viable and promising option to reduce anthropogenic CO2-emissions. At the moment numerous world-wide research projects investigate the feasibility of this concept under different geological and technical conditions. Among these projects, the RECOPOL-project („Reduction of CO2 Emissions by means of CO2 Storage in the Silesian Basin in Poland”) is working on a European level and includes laboratory experiments, reservoir modeling, and geophysics as well as a field test in the Upper Silesian Basin in Poland. As a partner in this broad international consortium, it was the task to perform single- and mixed-gas sorption experiments on coals from the test site under the prevailing in situ reservoir conditions. Further coal samples from different coal basins all over the world have been integrated into this study to strengthen gained results and to address the diversity of coal samples in terms of rank, maceral composition, and moisture. Experiments have been performed on 14 different coal samples. Analytical temperatures were 22, 32 and 45°C at pressures up to 230 bar (23 MPa). The thesis is divided into three major chapters, each of them dealing with a different, well defined question: • The first part contains measurements that arose from a Round Robin initiated by the US Department of Energy. The different laboratories were supposed to investigate five different samples from the Argonne Premium Sample Programme. Measurements performed included CO2 single-gas isotherms on dry coals at 22°C and pressures up to about 50 bar (5 MPa). Additionally, CH4 experiments under the same experimental conditions as well as CO2/CH4 mixed-gas sorption experiments at 45°C and pressures up to 180 bar (18 MPa) have been carried out. • The second part investigates the kinetics of gas sorption on coal. To address this issue, CO2 and CH4 adsorption/diffusion experiments on one coal sample from the Upper Silesian Basin in Poland have been conducted on different grain sizes and temperatures (32 and 45°C) as well as on dry and moist coals. • The third part concentrates on the preferential sorption from CO2/CH4 gas-mixtures on coal. Measurements have been performed on ten different coal samples at 45°C and pressures up to 230 bar (23 MPa). Dry and moisture-equilibrated coals as well as different source gas compositions have been used.

The objective of this work is the development of a new sewing technique, which allows the sewing of textile structures with access from one side. An industrial prototype is built in this work. Based on the existing ITA-sewing principle, a completely new machine is developed and used for the manufacturing of technical preforms for lightweight fibre reinforced plastic “FRP” products. For the fundamental design approaches of the machine development, all relevant machine and sewing features are identified and analysed. Additionally the influence of machine parameters on the sewing quality is tested and the effects of the sewing thread on the mechanical properties of FRP-parts are investigated in details. The economic potential of the developed sewing technique considering especially the production of FRP-parts is also analysed and presented.

In this research work, two mesophilic alcohol dehydrogenases namely baker’s yeast alcohol dehydrogenase (YADH) and Lactobacillus brevis alcohol dehydrogenase (LBADH) and one thermophilic alcohol dehydrogenase namely Thermoanaerobacter species alcohol dehydrogenase (ADH T) were immobilized by physical adsorption method. The effects of various immobilization and drying process parameters on the residual activity and the protein loading of the immobilized enzyme preparation were studied and thereby different optimum preparations were observed for different enzymes. Under the optimum immobilization conditions the residual activity achieved with YADH, LBADH, and ADH T was about 80%, 316%, and 325%, respectively. The hypothesis of bubble nucleation as a cause for loss of enzyme activity during the low pressure drying process was verified. The effects of various gas-phase reaction conditions on the initial reaction rate and the half-life of the optimized preparations were also studied. It was observed that addition of a suitable buffer (50 mM phosphate buffer, pH 7) or an optimum amount of sucrose (5 times greater than the amount of protein on weight basis) during the enzyme immobilization enhanced the half-life of the immobilized enzymes in the gas-phase reaction. Water activity significantly influenced the initial reaction rate and the half-life of the immobilized enzyme preparations in the gas-phase reaction. The optimum water activity found for LBADH and ADH T was the same (0.55). Under the optimized immobilization and gas-phase reaction conditions the thermo-stability of the ADH enzymes was enhanced tremendously. The space-time yield of (R)-phenylethanol was about 1000 g l-1 d-1 with LBADH and the space-time yield of (S)-phenylethanol was about 600 g l-1 d-1 with ADH T. The total turn over number of LBADH was about and the same of ADH T was about.

Modeling and simulation as a tool to support analyzing and improving chemical plants and processes is becoming more and more attractive. However, model development often is a lengthy task and requires an expert to obtain suitable results. Thus, in order to make further economic benefit from model-based activities, speeding up the model development process is an important objective. Fortunately, it becomes obvious that not all models have to be developed from scratch if a perspective is assumed that focuses on the lifecycle of an entity being modeled. Along this lifecycle, different models might be developed and all of them have some inherent dependencies because they all describe the same physical thing. Considering the lifecycle of a plant, for example, one recognizes that the models describing different modification stages of the plant are highly similar. Also, steady-state and dynamic models have some overlap such as the flowsheet structure of the plant. Further, data concerning physical property models and reaction kinetics is not only reusable, but should be kept consistent across various models. However, reusing those different parts is not that easy in practice. Models are developed by various employees of a company that sometimes change jobs or even the employer. Often, not only a single model is developed, but a variety thereof in order to take into consideration variations of some parameters or process alternatives. Further, those models are often developed using different tools to support various tasks. Tools and tasks range from simple mass balances and rough economic estimates using spreadsheets like MS Excel to dynamic simulation using e.g. gPROMS. Thus, it can be concluded, that model reuse leads to integration problems which must be tackled in order to leverage the efforts invested into model development. The first integration problem to solve is the combination of existing models in different formats and representations into a homogeneous library which is easy to browse or search. The second integration problem to address is to enable the combination of different models at simulation runtime so that they can be reused in their native simulation environment without reformulating or recoding them. The issues mentioned are exemplified with a case study from the production of polyamide6. capabilities of state-of-the-art tools with respect to model management and reuse are discussed and it is explained how the contributions of this thesis can improve the current situation. The architecture REALMS (Repository-based environment architecture for lifecycle modeling and simulation) of a heterogeneous modeling environment is then presented. It defines components suitable to solve the two problems described above, namely a model repository ROME (Repository for Open Modeling Environments) that permits storing, archiving, and assembling process models and a simulation platform CHEOPS which simplifies the integration of heterogeneous models at runtime. Both parts are integrated so that CHEOPS can execute heterogeneous experiments consisting of models stored in the repository ROME. A user interface based on a highly flexible component model is defined in order to enable the user to operate the overall system. The model repository ROME is based on a metamodel which is used to define a homogeneous view on the most relevant characteristics of chemical process models across various modeling tools. The metamodel is discussed as well as the mapping bewtween the metamodel and mathematical models presented in the polyamide6 scenario. The functionality realized with this metamodel and its implementation in an object-oriented database management system are then presented. The goal of the simulation platform CHEOPS is to run a simulation experiment which combines various simulators and coordinates them to achieve an overall solution of an experiment. Existing simulators are discussed with respect to their architectural properties and desired properties for an open simulation platform are stated. Based on these remarks, the architecture of the CHEOPS simulation platform and its realization are explained. Finally, the solution of the problem posed in the scenario presentation with the tools described in this work before conclusions are drawn.

Elastomer matrices extend the range of fiber reinforced plastics (FRP). The work presents an overview over materials and processing methods for such E-FRP. First, an overview of low-viscosity elastomer systems is given, which are suitable for E-FRP. Twelve different fiber-matrix-combinations based on polyurethanes and silicones are analysed with respect to their curing behavior and the mechanical properties. The fiber-matrix-adhesion of the silicone matrix resins on glass and aramid fibers was found to much lower than for the polyurethanes and silicones. The measured strength of the glass fiber reinforced samples are between 66,0 MPa and 649,4 MPa for the fiber direction and between 0,6 MPa and 14,6 MPa in cross fiber direction, while the aramid fiber reinforced samples reached a strength between 460,0 MPa and 880,0 MPa in fiber direction and between 56 and 2666 MPa in cross fiber direction. In contrast to the samples with polyurethane and epoxy matrix the silicone matrix samples did not exhibit a significant drop in storage modulus with temperature.For a pneumatic muscle with symmetrical laminate construction the expansion behavior of flexible E-FRP structures is described. A model for the expansion of such structures, which takes into account the matrix stiffness and fiber elongation, is developed.

The dissertation deals with the development of a dispersion process for the production of both non-magnetic and magnetic alginate beads. A combination of three different emulsifiers and silicon oil as dispersion medium is used for bead production. For bead characterization the iron and calcium content as well as the mean bead size and size distribution are determined. Light, electron and scanning force microscopy are used to describe bead morphology and surface structure. SQUID magnetometer measurements are used to determine the magnetic behaviour of the solid beads. The beads stability within a chelating agent is established by the release of the incorporated magnetite relative to the concentration of the chelating agent. To stabilize the bead chemically towards those agents, three different methods are compared. A surface coat of polyethylenimine offers the best protection. The polyethylenimin coat enables the magnetic alginate beads to separate (magnetic separation) the azo dye Kongored from its solutions. The second part of this dissertation describes studies of heating characteristics of ferrofluids and their influence on lymphocytes and HeLa cells. The ferrofluids are characterized through the determination of their iron content, particle size and inductive heating behaviour in a high frequency magnetic field. Their specific adsorption rates are determined. Cytotoxicology studies on lymphocytes enable a rough differentiation between the tested fluids concerning their cytotoxic effects. By incubing HeLa cells with a ferrofluid solution it is possible to determine the adsorbed iron content per cell in relation to the incubation period.