500 Naturwissenschaften und Mathematik
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- Education in Optics and Photonics (2)
- Art and Photonics (1)
- Artemisinin (1)
- Astronomical events (1)
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We present a planar chromatographic separation method for the compounds caffeine, artemisinin, and equol, separated on high-performance thin-layer chromatography (HPTLC) silica gel plates. As solvents for separation, methyl t-butyl ether and cyclohexane (1:1, V/V) have been used for equol, cyclohexane and ethyl acetate (7:3, V/V) for artemisinin, and ethyl acetate and acetone (7:3, V/V) for caffeine. After separation, the plate was scanned with a very specific time of flight-direct analysis in real time-mass spectrometry (TOF-DART-MS) system using the (M + 1)+ signals of equol, artemisinin, and caffeine. The (M + 1) peak of artemisinin at 283.13 m/z is clearly detectable, which is the proof that DART-MS is applicable for the quantitative determination of rather instable molecules. The planar set-up of DART source, HPTLC plate and detector inlet in a line showed higher sensitivities compared to desorption at an angle. The optimal detector voltage increases with the molar mass of the analyte, thus an individual determination of optimal detector voltage setting for the different analyte is recommended to achieve the best possible measurement conditions. In conclusion, DART-MS detection in combination with an HPTLC separation allows very specific quantification of all three compounds.
Art and Photonics
(2019)
In this paper we report on our continuous efforts to apply optics and photonics in art. This results in interdisciplinary projects which sometimes lead to concrete art installations.
We presented some of these projects at the UNESCO headquarters in Paris, at the opening ceremony of the International Year of Light and the inaugural ceremony of the International Day of Light.
Some newer projects, such as “A Maze: Ingenious Pipes” and “The Power of Your Eyes,” are also presented in this paper.
We present our twenty years of experience in the live broadcasting of astronomical events, with the main focus on total lunar eclipses. Our efforts were motivated by the great impact and high number of viewers of these events. Visitors from over a hundred countries watched our live broadcasts. Our viewer record was set on July 27, 2018, with the live transmission of the total lunar eclipse from the Feldberg, the highest mountain in the Black Forest, attracting nearly half a million viewers in five hours.
An especially challenging activity was the live observing of the Mercury transit on 9 May 2016, which we presented as ‘live astronomy’ with hands-on telescope. The main goal of this event was to awake our students enthusiasm for optics and astronomy.
Furthermore, we report on our experiences with the photography of optical phenomena such as polar lights and green flash.
O'Barro - Cocktails 4.0
(2019)
With the growing share of renewable energies in the electricity supply, transmission and distribution grids have to be adapted. A profound understanding of the structural characteristics of distribution grids is essential to define suitable strategies for grid expansion. Many countries have a large number of distribution system operators (DSOs) whose standards vary widely, which contributes to coordination problems during peak load hours. This study contributes to targeted distribution grid development by classifying DSOs according to their remuneration requirement. To examine the amendment potential, structural and grid development data from 109 distribution grids in South-Western Germany, are collected, referring to publications of the respective DSOs. The resulting data base is assessed statistically to identify clusters of DSOs according to the fit of demographic requirements and grid-construction status and thus identify development needs to enable a broader use of regenerative energy resources. Three alternative algorithms are explored to manage this task. The study finds the novel Gauss-Newton algorithm optimal to analyse the fit of grid conditions to regional requirements and successfully identifies grids with remuneration needs. It is superior to the so far used K-Means algorithm. The method developed here is transferable to other areas for grid analysis and targeted, cost-efficient development.
Brückenkurs Physik
(2019)
Dieses Lehrbuch fasst alle wesentlichen, für das Studium eines MINT-Faches relevanten Inhalte der Physik zusammen und hilft physikalisches Grundwissen aufzufrischen. Es unterstützt Studienanfänger dabei, die Routine in der konkreten Anwendung, die an der Hochschule vorausgesetzt wird, zu festigen. Dabei folgt die Stoffauswahl dem Mindestanforderungskatalog Physik, den ein Arbeitskreis aus Professoren der baden-württembergischen Hochschulen für angewandte Wissenschaften zusammengestellt hat.
Aufbau/Ansteuerung/Kalibrierung/Pilotierung eines Lautsprecher-Halbkreises für Lokalisationstests
(2019)
Seit September 2018 ist die Hochschule Offenburg im Besitz einer Hörkabine, in der ein Schallquellenlokalisationstest im Rahmen dieser Bachelorarbeit aufgebaut wurde. Eine Schallquellenlokalisation ist im Alltag für Normalhörende in den meisten Fällen keine Schwierigkeit. Wir Menschen sind in der Lage mit einer Genauigkeit von 1° bis 2° eine Schallquelle zu lokalisieren (Feigenspan 2017,S.624). Entfällt jedoch das Hörvermögen auf einer Seite, so verschlechtert sich die Lokalisationsfähigkeit erheb-lich. Um Schallquellen präzise lokalisieren zu können, werden optimaler Weise beide Ohren benötigt. Heutzutage gibt es viele Hörsysteme, um diverse Hörstörungen zu therapieren. Den-noch bleibt die Lokalisationsfähigkeit für Menschen mit einseitiger Taubheit, bezie hungsweise asymmetrischen Hörverlust eine Herausforderung. Ein Schallquellenlo kalisationstest findet Anwendung in der Klinik, um eine bestmögliche Versor gung/Therapie durch Hörsysteme zu gewährleisten. Ziel dieser Bachelorarbeit war der Aufbau eines Lokalisationstestes nach Leitlinien einer wissenschaftlichen Publikation, sowie die Durchführung an fünf freiwilligen Normalhörenden. Die Realisierung umfasste den Aufbau der Lautsprecher, die An-steuerung mithilfe einer externen Soundkarte und MATLAB, eine Kalibrierung der Lautsprecher und die Durchführung der Tests.