Microfluidic microbial fuel cell fabrication and rapid screening of electrochemically microbes

The demand for novel renewable energy sources, together with the new findings on bacterial electron transport mechanisms and the progress in microbial fuel cell design, have raised a noticeable interest in microbial power generation. Microbial fuel cell (MFC) is an electrochemical device that converts organic substrates into electricity via catalytic conversion by microorganism. It has represented a continuously growing research field during the past few years. The great advantage of this device is the direct conversion of the substrate into electricity and in the future, MFC may be linked to municipal waste streams or sources of agricultural and animal waste, providing a sustainable system for waste treatment and energy production. However, these novel green technologies have not yet been used for practical applications due to their low power outputs and challenges associated with scale-up, so in-depth studies are highly necessary to significantly improve and optimize the device working conditions. For the time being, the micro-scale MFCs show great potential in the rapid screening of electrochemically active microbes. This thesis presents how it will be possible to optimize the properties and design of the micro-size microbial fuel cell for maximum efficiency by understanding the MFC system. So it will involve designing, building and testing a miniature microbial fuel cell using a new species of microorganisms that promises high efficiency and long lifetime. The new device offer unique advantages of fast start-up, high sensitivity and superior microfluidic control over the measured microenvironment, which makes them good candidates for rapid screening of electrode materials, bacterial strains and growth media. It will be made in the Centre of Hybrid Biodevices (Faculty of Physical Sciences and Engineering, University of Southampton) from polymer materials like PDMS. The eventual aim is to develop a system with the optimum combination of microorganism, ion exchange membrane and growth medium. After fabricating the cell, different bacteria and plankton species will be grown in the device and the microbial fuel cell characterized for open circuit voltage and power. It will also use photo-sensitive organisms and characterize the power produced by the device in response to optical illumination.

Interpretazione per i media: il caso particolare delle interviste sul podio della Formula 1

This dissertation analyses the live simultaneous interpretation from English into Italian of six 2013 Formula 1 World Championship podium interviews and focuses on four main aspects: how the interpreter handled the décalage at the end of the interview and during the turn-taking; if he used any marker to indicate that he was starting to translate a new turn of the source text; what he did when overlapped speech in the source texts occurred; what happened when the Italian commentators talked during the interpreter’s translation. In the first chapter a description mainly of what a Formula 1 podium interview is and what an interpreter translates during the Formula 1 weekends is present. In the second chapter a literature review on media interpreting, with particular attention put on Straniero Sergio’s paper on translating Formula 1 press-conferences (2003), and turn-taking is provided. In the third chapter the methodology used to obtain and process the video and audio files of source and target texts and to transcribe them is described. We concentrated primarily on Thibault’s multimodal text transcription techniques (2000) and on how they were used and adapted to fit the purposes of this dissertation. In the fourth chapter the results obtained through the analysis of the source and target texts are shown and described, focusing only on the objectives of the dissertation, without aiming to provide a qualitative evaluation of the interpretations. In the fifth and last chapter the conclusions and some final remarks are made, based on the results obtained during the analysis and the hope for a more in depth knowledge of Italian Formula 1 interpreter’s working conditions.

Modelling and Verification of a Correction Factor to Evaluate the Efficiency of Solar Thermal Collectors with the Rapid Test Method

A new method for the evaluation of the efficiency of parabolic trough collectors, called Rapid Test Method, is investigated at the Solar Institut Jülich. The basic concept is to carry out measurements under stagnation conditions. This allows a fast and inexpensive process due to the fact that no working fluid is required. With this approach, the temperature reached by the inner wall of the receiver is assumed to be the stagnation temperature and hence the average temperature inside the collector. This leads to a systematic error which can be rectified through the introduction of a correction factor. A model of the collector is simulated with COMSOL Multipyisics to study the size of the correction factor depending on collector geometry and working conditions. The resulting values are compared with experimental data obtained at a test rig at the Solar Institut Jülich. These results do not match with the simulated ones. Consequentially, it was not pos-sible to verify the model. The reliability of both the model with COMSOL Multiphysics and of the measurements are analysed. The influence of the correction factor on the rapid test method is also studied, as well as the possibility of neglecting it by measuring the receiver’s inner wall temperature where it receives the least amount of solar rays. The last two chapters analyse the specific heat capacity as a function of pressure and tem-perature and present some considerations about the uncertainties on the efficiency curve obtained with the Rapid Test Method.