No description available.

The present study was focused to develop an analytical method to analyse â-lactam antibiotics present in aqueous solutions and able to be applied directly in the fields. The method here presented is based on the chemical reaction between â-lactam antibiotics with phosphomolybdic acid, a heteropolyacid able to be reduced by the thiols obtained after the acid hydrolysis of the â-lactam antibiotics. The blue product obtained, which is proportional to the antibiotic amount, is adsorbed on polyurethane foam, and the intensity of color is directly evaluated on the solid material by means of diffuse reflectance spectroscopy. For all six evaluated â-lactam antibiotics (amoxicillin, ampicillin, penicillin V, penicillin G, cefotaxime, cefuroxime), the analytical parameters achieved were: LOD = 0.03 µg/ml, LOQ = 0.1 µg/ml, RSD = 4.0 %. The study of possible interferences showed that using solid phase extraction is possible to eliminate even strong interferences as ascorbic acid, cysteine and reducing salts like stannous chloride. The present method has avoided, as much as possible, the use of expensive and contaminating solvents and chemical reagents. The method presents the possibility to be applied using only a desktop scanner and a personal PC for measuring the color of the adsorbed material on the PUF.

Within this thesis, the general developments of E-Business are discussed as well as their strategic implications and related opportunities for the chemical industry. To support strategic management decisions, potential scenarios are developed. On their bases, recommendations with regard to generic corporate strategy types can be drawn. Finally, E-Business related technologies are put into context again to show how they can support the successful implementation of the chosen strategy.

Both series of monoglyceride gels samples with different monoglyceride concentration of two monoglycerides C14 and C16/18 and series of water-in-oil emulsions that differ from flocculation, water concentration and biopolymer have been investigated by means of PFG NMR. Aim of the measurements was to determine microstructural parameters characterising such heterogenous systems. For the monoglyceride gels a return-to-the-origin probability, the average surface-to-volume ratio of the pore space as well as the tortuosity and dimensionality of the network could be calculated on the basis of echo attenuation and diffusion curves. Additionally pore size distributions have been determined for the monoglyceride gels. The results verify a postulated crystallisation process for monoglyceride gels and were validated by CryoSEM images and image analysis. The PFG NMR findings of the water-in-oil emulsions have been fitted with four various models which were developed in the context of this thesis and assume different diffusion behaviour of the water molecules. All models show individual deficits as the real movement of water molecules in the water-in-oil emulsions is more complex than assumed. Non flocculated and flocculated emulsions could be characterised and the droplet and aggregate size as well as the effective diffusion coefficient could be calculated. The results have been corroborated by CSLM images and image analysis.

A new detector for gas chromatography based on a microwave induced plasma has been developed. In order to record chromatograms emission spectra of diatomics are detected. Also a new method to obtain qualitative information on the analysed organic compound has been developed. The new detection method allows to get information about the atomic composition. In some cases the detector signals can be correlated with the constitution of the analysed substance. The detection method is based on the simultaneous detection of the spectral density of molecular bands of different diatomics as CC, CH, CN, NH, OH and an atomic hydrogen line. The resulting peak areas and the offset of the OH band are correlated with the analysed compounds by multivariate linear regression.

The Dissertation deals about migration and migrant rights in Germany and Europe. Even if many scholars have elucidated with convincing clarity that western nation states can produce an improvement of migrant rigths because of the autonomy of the legal system, the focus of this work is to point out the vulnerability of the legal process. The political and judical regulation of migration in Germany over the last forty years shows that the discretionary power of the authorities regarding to non-nationals is much stronger than regarding to nationals. And because of the transformation of the former welfare states to 'competition states' migration policies will be subsumed more likeley under the aspect of competitive advantages as in the era of the welfare state. The author persits that the judical improvement of migrant rights should be understood in terms of the national state and refers to political and economical general conditions courts can not (or will not) disregard in their decision - making -process.

The thesis treats the topic of the characterization and optimization of CMOS compatible photo sensor elements (CPSE). To understand the functionality of a CPSE a pro founded basic knowledge is necessary in the fields of the ray-, wave and quantum optics. Therefore all in this context necessary and principal equations are presented at the beginning of this work. In addition belongs in particular the statistic investigation of the absorption and emission processes in the field of the quantum optics, since these processes are the basis to understand the elementary noise sources within a CPSE. After an introduction to the available technological realization each element of the equivalent circuit diagram is analyzed. The optical quantum efficiency is developed intended for arbitrary angles and optical multi-layer sequences. The internal quantum efficiency is determined with a new mathematical approach and offers thereby more possibilities of the interpretation of the results compared to the classical physical approach which usually proceed from approximation solutions. The physical operation limit of a sensor and thus its efficiency is specified by the power of the noise sources. In this work it is analytically proven that the statements of Einstein concerning the kTC noise of an individual RC combination also apply to coupled RC combinations. Thus a highly simplified viewpoint of the CPSE and the Switched Capacitor amplifier is possible. Several optimization strategies to improve the optical quantum efficiency, for example the oxide perforation, are introduced and realized. The electro optical parameters can be usually determined by the measurement of special test-structures. Furthermore in this work new test-structures are developed, manufactured and measured under the aspect of high insensitivity to measurement errors. These results lead to the development of an Isochor diagram which permits all important design parameters. The Isochor diagram contributes thereby considerably to the conceptual design of a high-dynamic camera including image sensor. In particular the demanded application in the automotive field can be considered in detail. The achievement of the required goal parameters is documented by the measurement of the image sensor in the camera.

A problem in todays Internet infrastructure may occur when a streaming multimedia application is to take place. The information content of video and audio signals that contain moving or changing scenes may simply be too great for Internet clients with low bandwidth capacity if no adaptation is performed. In order to satisfactorily reach clients with various bandwidth capacities some works such as receiver-driven multicast and resilient overlay networks (RON) have been developed. However these efforts mainly call for modification on router level management or place additional layer to the Internet structure, which is not recommended in the nearest future due to the highly acceptance level and widely utilization of the current Internet structure, and the lengthy and tiring standardization process for a new structure or modification to be accepted. We have developed an improved active network approach for distributed and dynamic streaming multimedia environment with heterogeneous bandwidth, such as the case of the Internet. Friendly active network system (FANS) is a sample of our approach. Adopting application level active network (ALAN) mechanism, FANS participants and available media are referred through its universal resource locator (url). The system intercepts traffic flowing from source to destination and performs media post-processing at an intermediate peer. The process is performed at the application level instead of at the router level, which was the original approach of active networks. FANS requires no changes in router level management and puts no additional requirement to the current Internet architecture and, hence, instantly applicable. In comparison with ALAN, FANS possesses two significant differences. From the system overview, ALAN requires three minimum elements: clients, servers, and dynamic proxy servers. FANS, on the other hand, unifies the functionalities of those three elements. Each of peers in FANS is a client, an intermediate peer, and a media server as well. Secondly, FANS members tracking system dynamically detects the existence of a newly joined computers or mobile device, given its url is available and announced. In ALAN, the servers and the middle nodes are priori known and, hence, static. The application level approach and better performance characteristics distinguished also our work with another similar work in this field, which uses router level approach. The approach offers, in general, the following improvements: FANS promotes QoS fairness, in which clients with lower bandwidth are accommodated and receive better quality of service FANS introduces a new algorithm to determine whether or not the involvement of intermediate peer(s) to perform media post-processing enhancement services is necessary. This mechanism is important and advantageous due to the fact that intermediate post-processing increases the delay and, therefore, should only be employed selectively. FANS considers the size of media data and the capacity of clients bandwidth as network parameters that determine the level of quality of service offered. By employing the above techniques, our experiments with the Internet emulator show that our approach improves the reliability of streaming media applications in such environment.

The increasing complexity of integrated circuits (IC) requires IC internal contactless test-techniques for their function and failure analysis. The magnetic force microscopy-based current contrast imaging test-system makes the measurement of IC internal currents and current contrast imaging of IC areas possible. In this book a magnetic force microscopy (MFM) based current contrast imaging (CCI) test-system is presented. This new technology offers a promising tool for advanced contactless circuit internal function and failure analysis of IC. Contactless current images of 100nm wide interconnection lines and currents down to 1.7µA are presented. In this work the first high frequency current measurements up to 4.7 GHZ are demonstrated. Furthermore, there are some new detrimental effects on the technique which are discovered, explained by a new model and some possibilities for elimination of these effects are developed and presented. At least a failure analysis at a real IC is demonstrated.

The electrocatalytic characteristics of N4-chelatele electrodes is well known for several redox reactions. The N4-chelate can function thereby according to the principle of the heterogeneous redox catalysis as an intermediate fixed at the electrode surface. The main problem is the limited service life of such electrodes which prohibits the practical application in organic electrosyntheses. The electrochemical properties of N4-chelate electrodes and specially of copper phthalocyanine electrodes were investigated using several electrochemical methods. The results of these measurements lead into a significant refinement of the models of heterogenous redox reaction at N4-chelates. Furthermore models for the degradation process of N4-chelate electrodes could be derived. Finally, quite stable electodes were produced and tested.