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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Marcel Reich-Ranicki und das Wagner-Sonett

Grimm, Gunter E. 11 January 2002 (has links)
Marcel Reich-Ranickis statement concerning the sonnet in Wagner's opera "Die Meistersinger von Nürnberg" is wrong
222

Plasmaaktivierung von Polypropylenoberflächen zur Optimierung von Klebverbunden mit Cyanacrylat Klebstoffen im Hinblick auf die mechanischen Eigenschaften - Plasma modification of polypropylene for an optimization of bonds using cyanoacrylate adhesives from a viewpoint of mechanical properties

Mühlhan, Claus 28 January 2002 (has links)
In the present study low pressure plasma pretreatment has been investigated as an alternative to chemical primer pretreatment. The mechanical properties of Polypropylene-Cyanoacrylate bonding which were both, plasma and primer pretreated were compared. From the investigations, where the plasma parameters were systematically varied, it can be concluded that a very short exposure to an oxygen plasma and new curing conditions led to the best results. The shear strength after plasma pretreatment became even higher than after primer pretreatment.
223

"Elektronische Hirne". Zur literarischen Genese des Androiden

Grimm, Gunter E. 04 February 2002 (has links)
the android in literature and film, a survey
224

G.A. Bürger und J.W.L. Gleim. Hrsg. von H.J. Kertscher. Tübingen 1996

Grimm, Gunter E. 08 February 2002 (has links)
review of an anthology of essays concerning the two German poets Gleim and Bürger
225

Gottfried August Bürger und Gotthold Ephraim Lessing

Grimm, Gunter E. 12 February 2002 (has links)
The German author Gottfried August Buerger estimated Lessing's works, but they hadn't any influence on his poetical products. Nevertheless in his later theoretical writings Buerger mentioned Lessing as an important model.
226

Über den Einfluss einer wässrigen H<sub>2</sub>O<sub>2</sub>-Lösung auf die Verbrennung und Schadstoffemission eines DI-Dieselmotors - About the Influence of an Aqueous H<sub>2</sub>O<sub>2</sub> Solution on the Combustion and the Pollutant Emissions of a DI Diesel Engine

Franz, Berthold 10 May 2002 (has links)
This thesis reports on the influence of an aqueous H2O2 solution on the combustion process and the pollutant emissions of a direct injection naturally aspirated diesel engine. The effect of a H2O2/water addition into a flow reactor, into the exhaust gas and into the combustion chamber of a diesel engine was monitored by the measurement of gaseous (HC, CO, NOx, O2) and solid exhaust gas constituents. The effect on solid exhaust gas constituents was observed by the means of mass-, size- and number-related measurement techniques. Additional experiments with cycle resolved spectroscopy and pressure indication were performed in the case of H2O2/water injection into the combustion chamber. The results show that a significant decrease of gaseous and solid pollutant emissions of a diesel engine is possible with H2O2/water addition. Particularly the strong effect of a H2O2/water injection into the combustion chamber on soot oxidation indicates that OH radicals play an important role in the process of soot oxidation wi in the combustion chamber.
227

Das Kollapsverhalten moderner Binnengüterschiffe unter Berücksichtigung struktureller Imperfektionen . The collapse behaviour of modern inland vessels under the consideration of structure imperfections

Meinken, Andreas 21 May 2001 (has links)
Modern inland vessels are open-top double-hull ships with an unusually large aspect ratio, a shallow draught and an extremely long cargo hold. These ships have a very low bending and torsional rigidity. Due to minor collisions, grounding in shallow water, corrosion and fatigue the state of the ship structure changes appreciably in course of time. These imperfections reduce the stability and strength of the structure. The safety against total collapse decreases. This thesis is showing the results of a systematic investigation of typical ship-constructions with the Finite-Ele-ment-Method (FEM). The failures of a complex structure like a ship hull is not entails by one item. Usually more than one negative factors are responsible. For example these are an unfavourable cargo distribution, the reduction of the plate thickness and the large imperfections during ser-vice. Normally ships are construct for a relative long working season (20-30 years and more). In course of this long term the features of the structure are changing considerably. Already the dimensions of new components must take care of it. As an example, the traditional calculations methods recognize an extra charge for the corrosion. To investigate the structure stability it is very difficult to take into account the imperfections (e.g. pre-deformations) with analytical calculation methods. This is a typical application for the FEM. The introduction part of the thesis will showing different possibilities to calculate the structural stability and strength of an inland vessel. On account to the points mentioned above (imperfections, load distributions) the traditional calculation methods are not sufficient. Using the Finite-Element-Method (FEM) a new calculation concept will be introducing to achieve these elaborate analyses. In future the influence of local damages to the global structure should be a minimum. The heart of the procedure is the registration and numerical consideration of typical damages. It is to investigate which imperfections are important to consider and which are negligible. A classification of the imperfections will support this. To consider these imperfections the mentioned calculation concept will be used. First, the simple example of a stiffened plate and a box girder will be using to discuss the influence of imperfections on the structure behaviour. Later this knowledge of these investigations will be utilizing for the analysis of typical inland vessels. The FE-models of a pusher barge and a modern inland container vessel will be introducing and their calculation results will be showing. These are deformations and stresses for various cargo distributions. Additionally the non-linear results for extreme loads will be presenting to simulate the collapse behaviour of the vessel. At least constructive modifications (e.g. longitudinal girder, high-tensile steel) will be discussing to show their effects. With this, the new ship should be lightweight, easy to build and with a maximum security against global breakdown. The last point is a short discussion of a few "special features" for future investigations. For example these are the application of multi-processor software (to reduce the calculation time) and the using of optimizing software
228

Optimierung des Elutionsverhaltens von Aschen aus der Sonderabfallverbrennung - Optimisation of the leaching behaviour from hazardous waste incineration ashes

Reich, Jens 25 May 2001 (has links)
From hazardous waste incineration (HWI) in rotary kilns ashes are generated as solid residues. In this thesis the effect of limestone addition to HWI-ashes was examined for the elution behaviour of heavy metals after a temperature treatment. Experimental results were compared to theoretic modelling. After treatment at 1200°C, the typical temperature for hazardous waste incineration, a minimum of heavy metal leaching from HWI-ashes was found at CaO-contents between 15 and 20%. On the one hand, lower melting temperatures of the ashes were measured after limestone addition. The melting process may lead to immobilisation of heavy metals in glassy phases of the ash. On the other hand, thermodynamic equilibrium calculations prove the decrease of the solubility of heavy metals as for example zinc, lead and chromium due to a changed chemical speciation. In future a HWI-ash optimised with regard to heavy metal leaching could be disposed off to lower landfilling costs, so that the incineration costs of hazardous waste in rotary kilns may also decrease.
229

Entwicklung eines Verfahrens zur Beurteilung des Schädigungszustandes von Schrägaufzugseilen an Hochöfen mittels magnetinduktiver Streuflußmessung - Development of a system for the evaluation of skip steel cables of blast furnaces using electromagnetic testing

Both, Christian 25 May 2001 (has links)
Based on the problem of a total evaluation of skip steel cables of blast furnaces two computer aided procedures for the analysis of the measured data of electromagnetic steel cable testing are developed. The first procedure is useful to detect inner and outer broken wires and simulates the analysis of a skilled inspector by a pattern classification algorithm using fuzzy-logic. Like an inspector this system has to be trained. This is implemented with the help of a genetic algorithm. The second procedure is helpful serves as evaluation of accumulated inner faults of steel cables. Therefore two characteristic values describing the inner condition are determined by frequency analysis of the measured data. - Ausgehend von der Problemstellung einer umfassenden Beurteilung des Schädigungszustandes von Schrägaufzugseilen an Hochöfen werden zwei rechnergestützte Auswerteverfahren für die magnetinduktive Streuflußprüfung von Drahtseilen entwickelt. Das erste Verfahren dient der Erkennung innerer und äußerer Drahtbrüche und bildet die Auswertemethodik eines erfahrenen Inspekteurs in einem Musterklassifikator basierend auf Fuzzy-Logic nach. Den Erfahrungsprozeß des Inspekteurs vollzieht das Verfahren durch eine Optimierung mittels genetischen Algorithmus anhand realer Meßdaten nach. Das zweite Verfahren dient der Abschätzung des inneren Schädigungszustandes eines Drahtseiles hervorgerufen durch Schadenshäufungen. Dazu erfolgt die Berechnung zweier charakteristischer Kennwerte aus eine Frequenzanalyse der aufgezeichneten Meßdaten.
230

Herstellung von Partikeln durch elektrostatische Zerstäubung von Flüssigmetallen in gasförmiger Umgebung - Production of particles via electrostatic atomization of liquid metals in gaseous environments

Lohmann, Martin 28 May 2001 (has links)
Fine solid particles, especially nano-particles, are of great interest for the synthesis of new materials. There is also a strong demand for newer and more precise contact technologies of electronic components due to the higher getting integration of electronic devices. These new technologies may be based on submicron conducting particles, e.g. for producing solder pastes. In the present thesis a process was developed for the production of micron and submicron conducting particles by the use of electrostatic atomisation of liquid metals. The atomization process is based on the instability of conducting liquids in a strong inhomogenous electric field. The free liquid surface is transformed into a cone shape, from where a thin liquid jet is emitted. This jet breaks up into a spray of fine unipolary charged droplets immediately after the emission. Under defined circumstances the droplets have a narrow size distribution and can be extracted for other applications without additional classification methods. The rapid solidification leads to defined spherical particles, depending on the used metal, and the unipolar charge to a low agglomeration. The high electrical field, which is necessary for the atomization, causes electrical discharges of the ambient gas and disturbes the atomization process. To reduce these discharges a special pressure chamber was constructed, which is filled with quenching gas as SF6 with over-pressures of up to 12 bar. The electrostatic atomisation was applicated for liquid metals only in an ultra high vacuum up to now. The production of aerosol particles may have advantages not only due to available cheaper online measurement techniques. By the use of aerosol measurement techniques a direct statement about the particle size, the particle number concentration and the mean charge on the particles is possible. The atomization was investigated for metals as well as for eutectic alloys with a low melting point and a low surface tension. The results show, that spherical particles with a diameter down to a few hundred nanometer could be produced. In addition the production of thin and homogenous granular films was possible. To compare and verify the experimental results a simplified numerical model of the spraying process with respect to the space charge was developed. By calculating the particle trajectories from the emission source to the collector plate an estimation of the spray cloud geometry and the emitted electrical current was possible. An interesting observation was the self induced size segregation of the particles, which occurred in the experiments and in the numerical simulations. This effect can be used for a defined expansion or focussing of the deposition area on the target. Here there may be found some interesting applications for the point spraying.

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