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Showing 1 to 20 of 79 for “"Technische Chemie"”.
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Korrosionsverhalten metallischer und keramischer Werkstoffe in Prozeßgasen zur Herstellung von Solarsilizium
The increasing emission of CO2, due to the growing power consumption, requires more and more efforts to replace fossile fuels by sophisticated no-emission systems in power generation. Using photovoltaics is one possible option. Producing electricity by solar energy, photovoltaics may contribute to …
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Selective oxidation and segregation in commercial steels and model alloys : (tools for improving the surface wettability by liquid Zn during hot dip galvanizing
To improve a wettability of annealed high strength steels and model alloys by Zn bath, two processes were applied to modify the surface: selective oxidation during annealing in 5% H2/N2 at 820°C at dew points -60, -30 and 0°C on HSS (DP 500, Ti-IF and TiNb-IF), and preoxidation in air at 700°C with …
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Bioabbaubare Polymernetzwerk-Systeme mit Formgedächtniseffekt und kristallisierbarem Schaltsegment
This work describes the synthesis and properties of new polymer systems of biodegradable shape memory thermosets. The combination of only four different monomer units and three network architectures allows the design of polymeric materials with a broad spectrum of properties. By variation of the …
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Untersuchungen zur Modifizierung der Zellmembranlipide von Wolle durch industrielle Ausrüstungsprozesse
The aim of the present work was to examine, if wet processing of wool e.g. chlorination, chlorine/Hercosett treatment and reactive wool dyeing, generates modified lipids, which might contribute to skin irritation. Therefore, the composition of solvent extractable cell membrane lipids of …
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Plasmagestützte Oberflächenmodifizierung von Polypropen
The use of PP fibres in apparel industry is limited due to the poor dyeability of PP in exhaust-dyeing processes. One reason for the poor dyeing behaviour is the hydrophobic surface of PP, which is only hardly wettable with aqueous dye solutions. Another reason is the low wet fastness, as a result …
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Thermodynamische Modellrechnungen zur Entwicklung korrosionsbeständiger keramischer Werkstoffe für den Flüssigascheabscheider in kohlenstaubbefeuerten Energieanlagen
In the present work thermodynamic calculations using the computer program FACT were carried out under simulated process conditions in order to simulate the cooling behaviour of molten slags and the stability of phases in systems Al2O3-SiO2-ZrO2, Al2O3-Cr2O3-SiO2-ZrO2, Al2O3-Cr2O3-SiO2 und …
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Optimierung der Energienutzung bei der Aluminiumherstellung
Analysing the sustainability of the aluminium industry, energy input is an important indicator. Besides the use of energy resources, energy consumption has a negative impact on the ecology, e.g., emissions caused by energy conversion, as well as economic effects due to energy costs. In this paper, …
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Simulationsrechnungen zur FTIR-reflexionsspektroskopischen Charakterisierung von Schicht- und Fasersystemen
The Fourier-Transform-Infrared (FTIR) specular reflection spectroscopy has been applied to non-destructive characterization of layered systems, ceramic fibres and fibre composites. The required finding out of the optical functions of the sample materials as well as of the parameters of the sample …
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Optimization of the dehydration of glycerol to acrolein and a scale up in a pilot plant
The value of glycerol can be increased in the transformation to acrolein in the presence of a heterogeneous acidic catalyst. The aim of this project is the investigation of the reaction properties in means of conversion to acrolein. Complete glycerol conversion and high acrolein selectivity are the …
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Dynamik der Schichtabscheidung von Keramiken mit KrF-Excimer-Laserstrahlung
The dynamic during pulsed laser deposition of Al2O3, BaTiO3 and ZrO2 is investigated. The expansion of the laser induced plasma is analytically described as a function of the processing variables and material parameters, considering elastic or inelastic collisions between the ablated particles and …
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Experimentelle Untersuchungen zum Korrosions- und Auflösungsverhalten von künstlichen Mineralfasern in wäßriger Lösung
In the construction industry the use of synthetical mineral fibrous insulating material (MMMF) has become a widespread indispensable material. Beside a continous adaption of the physical properties of MMMF to the specific applications recently the characterics of glass corrosion are subject to a …
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Entwicklung eines Energiemodells für Analysen von Energiebereitstellungsstrukturen
The transformation of primary energy carriers and the energy supply to the consumers is directly connected to the use of renewable and non-renewable resources, emission into environment and the production of waste. These energy-related material flows are of main interest in the assessment of an …
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Rekonstruktion bronzezeitlicher Gießereitechniken mittels numerischer Simulation, gießtechnologischer Experimente und werkstofftechnischer Untersuchungen an Nachguss und Original
Archaeological findings normally arouse our interest in well arranged exhibitions. But thorough knowledge about their technical properties and their production process can reveal hidden secrets about the handcraft, the living and the social evolution of our prehistoric ancestors. Unfortunately the …
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Untersuchungen zur Gefriertrocknung biologischer Zellen am Beispiel menschlicher Erythrozyten
Freeze-drying is a state of the art process for stabilization of pharmaceutical or biotechnological products. However, a successful preservation of living cells by freeze-drying is still a big challenge. This is mainly due to increased requirements on the product quality, since even smallest …
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Ermittlung von Materialkennwerten von Kunststoffschüttgütern und Simulation der Vorgänge im Einzugsbereich von konventionellen Einschneckenextrudern
Mathematical simulations are already frequently used for the design of single-screw extruders for plastics processing and have the advantage of saving not only time and personnel, but are also economical. In order to obtain simulation results for the feed section of single-screw extruders with a …
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Tenside, Polymerbausteine und Polymere aus nachwachsenden Rohstoffen durch Epoxidringöffnungen mit Aminen und enzymatische Polykondensationen
This work describes new syntheses of surfactants and polymers based on renewable raw materials, mainly oleochemical epoxides and polyolamines based on carbohydrates using. Polyolamines, which are available by reductive amination of reducing carbohydrates, were reacted with different epoxides to …
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Modellierung der Verfestigung technischer Aluminiumlegierungen
The large strain work hardening behaviour of technical aluminium alloys as function of the deformation temperature and strain rate is described in two ways. First a phenomenological description is made using well known models from literature. For some specific cases the models are expanded. …
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Einsatz neuronaler Netze zur Optimierung der Prozeßführung bei der Blasstrahlerzeugung
Basic Oxygen Steelmaking (BOS) is a current technology of refining iron to steel. Efficiency and quality depend on exact calculation of actual and estimated process parameters. Artificial neural networks (ANN) provide the facility of improving accuracy of process control. Within this thesis, a …
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Vorhersage der mechanischen Folieneigenschaften bei der Schlauchfolienextrusion
The manufacturing of blown films made of thermoplastic materials is considered an important processing technique for polymer raw material. Today, one goal of the further development of the blown film extrusion is the reduction of raw material application while maintaining or improving the quality …
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Optimization and control of selenium chemistry and color in flint glass melts
The selenium chemistry in the decoloration process in flint glass melts was investigated both in commercial practice and in laboratory. Samples were taken from two furnaces of a flint glass production site, analysed with respect to Se, Fe, redox state, and color. Color defects during production …
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