München, Techn. University, Diss., 2004.

Techn. University, Diss., 2003--Berlin.

Universiẗat, Diss., 2004--München.

Submitted by Diogo Barreiros (diogo.barreiros@ufba.br) on 2017-02-17T14:25:30Z No. of bitstreams: 1 serpentini2009.pdf: 12924209 bytes, checksum: 2f48977be81dbf0b08b3ccfa824d2703 (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2017-02-17T14:34:15Z (GMT) No. of bitstreams: 1 serpentini2009.pdf: 12924209 bytes, checksum: 2f48977be81dbf0b08b3ccfa824d2703 (MD5) / Made available in DSpace on 2017-02-17T14:34:15Z (GMT). No. of bitstreams: 1 serpentini2009.pdf: 12924209 bytes, checksum: 2f48977be81dbf0b08b3ccfa824d2703 (MD5) / É descrito neste trabalho o desenvolvimento completo de uma câmera digital especial para uso científico e sua aplicação em espectrofotometria. São detalhadas todas as etapas do desenvolvimento da câmera, que cobre a fundamentação teórica até o projeto de circuitos, montagem de placas de circuito impresso e desenvolvimento de softwares. A câmera desenvolvida neste trabalho foi proposta com intuito de ser inserida ao espectrofotometro construído no Laboratório de Propriedades Ópticas (LaPO) do Instituto de Física da Universidade Federal da Bahia. Este equipamento permite a mudança do método de varredura atualmente utilizado para um sistema instantâneo de aquisição, o que proporciona uma maior produtividade dos pesquisadores do LaPO. É proposto também um método para simplificacão na geração de sinais em sistemas embarcados, com possibilidade de uso em sistemas de tempo real. Experimentalmente após integração e calibração da câmera ao espectrofotometro, foram adquiridos dados que se mostraram satisfatórios aos propósitos experimentais.

Thesis (Master Diploma (Electrical Engineering))-- Cape Technikon, Cape Town, 1988 / This thesis describes the control system developed to improve the efficiency of star acquisition on a ground-based optical telescope. "Star Acquisition" refers to the process of identifying the star of interest in a field of stars and centering it on the optical axis of the telescope , as well as setting an autoguider detector on a suitable star so the autoguider can improve the tracking performance of the telescope. Efficiency is improved by making all functions remote controlled , so the astronomer does not have to move between the control room and the telescope to operate the instrument.

abstract: A thorough exploration of star formation necessitates observation across the electromagnetic spectrum. In particular, observations in the submillimeter and ultra-violet allow one to observe very early stage star formation and to trace the evolution from molecular cloud collapse to stellar ignition. Submillimeter observations are essential for piercing the heart of heavily obscured stellar nurseries to observe star formation in its infancy. Ultra-violet observations allow one to observe stars just after they emerge from their surrounding environment, allowing higher energy radiation to escape. To make detailed observations of early stage star formation in both spectral regimes requires state-of-the-art detector technology and instrumentation. In this dissertation, I discuss the calibration and feasibility of detectors developed by Lawrence Berkeley National Laboratory and specially processed at the Jet Propulsion Laboratory to increase their quantum efficiency at far-ultraviolet wavelengths. A cursory treatment of the delta-doping process is presented, followed by a thorough discussion of calibration procedures developed at JPL and in the Laboratory for Astronomical and Space Instrumentation at ASU. Subsequent discussion turns to a novel design for a Modular Imager Cell forming one possible basis for construction of future large focal plane arrays. I then discuss the design, fabrication, and calibration of a sounding rocket imaging system developed using the MIC and these specially processed detectors. Finally, I discuss one scientific application of sub-mm observations. I used data from the Heinrich Hertz Sub-millimeter Telescope and the Sub-Millimeter Array (SMA) to observe sub-millimeter transitions and continuum emission towards AFGL 2591. I tested the use of vibrationally excited HCN emission to probe the protostellar accretion disk structure. I measured vibrationally excited HCN line ratios in order to elucidate the appropriate excitation mechanism. I find collisional excitation to be dominant, showing the emission originates in extremely dense (n&sim10;11 cm-3), warm (T&sim1000; K) gas. Furthermore, from the line profile of the v=(0, 22d, 0) transition, I find evidence for a possible accretion disk. / Dissertation/Thesis / Ph.D. Physics 2012

This study evaluated the possible uses for a custom-made Capillary Electrophoresis Contactless Conductivity Detector (CE-CCD). One of the key objectives was to determine whether measurements of conductivity with the device could replace UV-spectroscopy to analyze a range of samples, in particular PVA-MB and monosaccharides. Furthermore, to determine the feasibility of using the specific device as a substitute for UV-spectroscopy analysis, two commercial reference devices were used: one contact based conductivity detector and one potentiostat. Changes in resistance and voltage drops of samples containing the analytes were used to determine whether the analysis with the custom made CE-CCD could replace analysis with UV-spectroscopy. The signal from the PVA-MB compared to variation in the signal of the background electrolyte was discovered to be too great for CE-CCD to be applied as a substitute for UV-spectroscopy.  However both monosaccharides analyzed in the study, glucose and galactose could be detected. Glucose could accurately be detected down to 50 μM and galactose down to 25 μM. A semi-empirical calculation estimated a lower limit of 5 μM for glucose and roughly 8 μM for galactose. PVA-MB could not be detected with the custom made CE-CCD while the monosaccharides can be detected in a range low enough to allow the detector to replace UV-spectroscopy for analysis. The best measurements taken with the detector were not as low as the best data found for UV-spectroscopy, but similar electrochemical applications were found to have reached similar or better values. Further development of the detector may lower its limit of detection to approach and possibly exceed the better measurements taken with UV-spectroscopy.

No description available.

No description available.

No description available.