Zur Analyse von Troepfchenspektren in Gasturbinenbrennkammern mittels des Speckleverfahrens

Diese Arbeit beschaeftigt sich mit der integralen Erfassung von Tropfendurchmessern und die beruehrungslose Bestimmung der Fluggeschwindigkeiten und -richtungen der Brennstofftroepfchen in Gasturbinenbrennkammern mit Hilfe einer Laser-optischen Messmethode. Der Prinzipielle Vesuchsaufbau, die Kalibrierung, rechnergestuetzte Bilderfassung und die Statistische Auswertung mit Hilfe der Datenreduktion werden eingehend behandelt. (AKF)The doctoral thesis deals with the integral detection of drop diameters and contactless determination of flying velocities and directions of the fuel droplets in gas turbine combustion chambers by means of a laser-optical measurement method. The basic test setup, calibration, computerized image acquisition and statistical evaluation by means of data reduction are covered in detail. (AKF)SIGLEAvailable from TIB Hannover: H93B2085 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Conceptual Design of the High-Speed Propelled Experimental Flight Test Vehicle HEXAFLY

© 2015 AIAA American Institute of Aeronautics and Astronautics. All rights reserved. A concise overview of the overall layout of an experimental powered high-speed flight vehicle including its subsystems is given. A mission scenario, the different flight segments and events to which the payload is exposed are described and justified. This allowed the definition of the aero-thermo-mechanical loads required to conceptually design all elements on board of the vehicle. The final vehicle configuration could achieve the different mission objectives. In particular an aero-propulsive balance, i.e. thrust ≥ drag and lift ≥ weight, could be established at a cruise Mach number of M = 7.4 on the basis of a hydrogen powered scramjet engine while guaranteeing a good aerodynamic efficiency L/D ≥ 4 in a stable, trimmed and controlled way. The experimental combustion campaign could last for at least for 3s up to 9s pending on the finally obtained flight level. This test time is very valuable as it is about 3 orders of magnitude higher of what can be tested in European ground facilities. The vehicle made maximum use of databases, expertise, technologies and materials elaborated in previously EC co-funded projects ATLLAS I & II and LAPCAT I & II. Based on this conceptual design, the consortium has arrived at a key point where they feel comfortable to go to the next step in establishing a detailed design of the vehicle and the preparation of the launch vehicle and flight campaign.status: publishe

Bodengebundene Messungen relevanter Spurengase zur Erforschung der Ozonchemie in der arktischen Stratosphaere mit Fourier-Spektrometern

Es handelt sich um den Schlussbericht eines vom BMFT gefoerderten Vorhabens, das unter dem Foerderkennzeichen 01 V0Z15 6 vom 01.03.1990 bis zum 30.06.1993 lief. Das Ziel des Vorhabens lag in der Erfassung von Saeulengehalten von Spurengasen, die fuer die Ozonchemie und fuer die Ausbildung von Ozonsenken in der Arktis relevant sind. Dabei sollte geklaert werden, welchen Anteil dynamische und chemische Prozesse haben und ob die Chemie der arktischen Stratosphaere Parallelen zu denjenigen in der Antarktis aufweist. Als Geraete wurden zwei Fourier-Transformationsspektrometer (FTS) eingesetzt, die das IR-Spektrum des direkten Sonnenlichts messen, das die atmosphaerischen Spurengase in Abhaengigkeit ihrer Konzentration selektiv schwaechen. Zur Berechnung der Saeulendichten werden synthetische Spektren unter Beruecksichtigung der Messgeometrie an die gemessenen angepasst und die zur Berechnung der synthetischen Spektren verwendeten vertikalen Profile der Mischungsverhaeltnisse in einem Least-squares-fit-Verfahren variiert. Ein Vorteil dieser Messtechnik ist, dass in derselben sondierten Luftmasse die Saeulengehalte vieler Spurengase simultan bestimmt werden koennen. (orig.)This is the final report of a project, which was funded by the German Federal Ministry for Research and Technology (BMFT), file No. 01 V0Z15 6, and was conducted from 1 March, 1990 until 30 June, 1993. It was the goal of the project to record zenith column amounts (ZCA's) of trace gases, which are relevant to ozone chemistry and to the development of ozone sinks in the Arctic. Above all, the contribution of dynamic and chemical processes was to be clarified as well as the question whether parallels can be drawn between the chemistry of the Arctic and the Antarctic stratosphere. The equipment used were two Fourier transform spectrometers (FTS). They allow the IR spectrum of direct sunlight to be measured which is attenuated selectively by the atmospheric trace gases, dependent on their concentrations. To be able to calculate the ZCA's, synthetic spectra are fitted to the measured ones taking into account the measuring geometry, and by varying vertical profiles of the mixing ratios used to calculate the synthetic spectra. An advantage offered by this measuring technique is that the ZCA's of many trace gases can be determined simultaneously in the same probed mass of air. (orig.)SIGLEAvailable from TIB Hannover: ZA 5141(5242) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Calcium Binding Properties of the Kingella kingae PilC1 and PilC2 Proteins Have Differential Effects on Type IV Pilus-Mediated Adherence and Twitching Motility

Kingella kingae is an emerging bacterial pathogen that is being recognized increasingly as an important etiology of septic arthritis, osteomyelitis, and bacteremia, especially in young children. The pathogenesis of K. kingae disease begins with bacterial adherence to respiratory epithelium, which is dependent on type IV pili and is influenced by two PilC-like proteins called PilC1 and PilC2. Production of either PilC1 or PilC2 is necessary for K. kingae piliation and bacterial adherence. In this study, we set out to further investigate the role of PilC1 and PilC2 in type IV pilus-associated phenotypes. We found that PilC1 contains a functional 9-amino-acid calcium-binding (Ca-binding) site with homology to the Pseudomonas aeruginosa PilY1 Ca-binding site and that PilC2 contains a functional 12-amino-acid Ca-binding site with homology to the human calmodulin Ca-binding site. Using targeted mutagenesis to disrupt the Ca-binding sites, we demonstrated that the PilC1 and PilC2 Ca-binding sites are dispensable for piliation. Interestingly, we showed that the PilC1 site is necessary for twitching motility and adherence to Chang epithelial cells, while the PilC2 site has only a minor influence on twitching motility and no influence on adherence. These findings establish key differences in PilC1 and PilC2 function in K. kingae and provide insights into the biology of the PilC-like family of proteins