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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Tratamento de águas residuárias em células a combustível microbianas e geração de energia elétrica direta: fundamentos e aplicação / Wastewater treatment in microbial fuel cell and direct electrical power generation: fundamentals and aplication

Eduardo Dellosso Penteado 08 April 2016 (has links)
Neste trabalho avaliou-se a influência das condições operacionais da célula a combustível microbiana (CCM) na remoção de matéria orgânica de águas residuárias e na geração de energia elétrica direta. As Hipóteses 1, 2 e 3 verificaram respectivamente as influências do tempo de detenção hidráulica (TDH), das condições mesofílica (25 ºC) e termofílica (55 ºC) de temperatura e da razão de recirculação (R) do efluente no cátodo da CCM (0, 1, 3 e 5) na geração de energia elétrica, na adesão e na comunidade microbiana e na remoção de DQO em CCM sem membrana de íon seletiva alimentada com água residuária sintética a base de sacarose. As Hipóteses 1, 2 e 3 foram aceitas. A redução do TDH permitiu maior geração de energia e dominância na comunidade microbiana e menor adesão da comunidade microbiana ao eletrodo. Enquanto que longos TDH removeram mais DQO, porém geraram menores valores de tensão elétrica. As condições termofílicas apresentaram maiores valores de tensão elétrica gerada e maior dominância da comunidade microbiana e menor adesão microbiana ao eletrodo e eficiência de remoção de DQO. A constante cinética aparente em condição termofílica ( 0,035 h-1) foi duas vezes menor que em condição mesofílica ( 0,083 h-1). O aumento da R melhorou a geração de energia e a remoção de DQO, pois houve melhor transferência de massa do meio líquido para os microrganismos e do meio gasoso para liquido e menor concentração de biomassa aderida ao eletrodo do cátodo aumentando a tensão elétrica gerada. Na Hipótese 4, verificou-se o uso e o efeito do TDH no tratamento de vinhaça de cana de açúcar em CCM sem membrana trocadora de íon seletivo operada em condição termofílica. A CCM foi capaz de remover a matéria orgânica da vinhaça de cana de açúcar e gerar energia elétrica direta, validando a Hipótese 4. As hipóteses 5, 6 e 7 avaliaram as influências da relação DQO, nitrogênio e fósforo da água residuária de produção de vinho, do tempo de retenção celular (TRC) e da configuração do eletrodo no desempenho de CCM de duas câmaras usando membrana de íon seletivo. Acataram-se as hipóteses 5, 6 e 7. O desbalanceamento entre DQO, nitrogênio e fósforo da água residuária de produção de vinho é um dos principais obstáculos para o uso desta tecnologia e a relação de DQO:N:P de 700:10:1 tem elevado potencial para gerar energia elétrica direta em CCM, embora não seja eficiente na remoção de matéria orgânica. A geração de energia aumenta com a redução do TRC, visto que há seleção dos microrganismos eletrogênicos e aumento da carga orgânica volumétrica específica reduzindo a competição por substrato. Entretanto, o TRC não influenciou a remoção de matéria orgânica, pois somente uma pequena parte da DQO foi removida similar em todos os TRC. As características físicas do eletrodo como a porosidade, a rugosidade e a densidade de área do eletrodo e a biocompatibilidade do eletrodo são fatores determinantes para aumentar o desempenho da CCM. Entre os eletrodos estudados, o feltro de carbono foi o melhor material encontrado. / In this work the influence of the operational conditions of the microbial fuel cell (MFC) were evaluated in organic matter removal from wastewater treatment and in the power generation. Hypotheses 1, 2 and 3 respectively checked the influences of hydraulic retention time (HRT), of mesophilic and thermophilic conditions (25 °C and 55 °C, respectively) and the recirculation ratio (R) of the effluent in cathode of MFC (0, 1, 3 and 5) in the power generation, microbial adhesion and community and COD removal of membraneless MFC fed with synthetic wastewater based on sucrose. Hypotheses 1, 2 and 3 have been accepted. Reducing the HRT increased the power generation and the dominance in microbial community and decreased the COD removal efficiency and microbial adhesion to the electrode. Long HRT more efficiently removed the organic matter but generated lower voltages. The thermophilic conditions yielded a more dominant microbial community that favored power generation compared with the mesophilic conditions because of reduced microbial adhesion to the electrode. The COD removal efficiencies were higher under mesophilic conditions than under thermophilic conditions due to the higher apparent kinetic constant at mesophilic conditions (0.083 h-1) than in thermophilic conditions (0.035 h-1). Increasing the R improved the power generation and the COD removal, because the mass transfer in the liquid medium for microorganisms was improved and the biomass adhered to the cathode electrode decreased increasing the voltage. In Hypothesis 4, the use and effect of HRT in treating sugar cane vinasse in membraneless MFC operated at thermophilic conditions were evaluated. The CCM was able to remove the COD of sugarcane vinasse and generate electricity directly, confirming the hypothesis 4. Hypotheses 5, 6 and 7 assessed the influences of COD, nitrogen and phosphorus ratio in winery wastewater, of sludge retention time (SRT) and of electrode configuration in dual chamber MFC. Hypotheses 5, 6 and 7 were adopted. The misbalance between COD, nitrogen and phosphorus from winery wastewater is a major obstacle to the use of this technology and COD:N:P ratio of 700:10:1 had high potential to generate power in MFC, although it is not effective in removing organic matter. The power generation increases with the reduction of the SRT, since there were the selection of bioeletrogenic microorganisms and increased the volumetric organic load rate reducing competition for substrate. However, the SRT did not affect the removal of organic matter, because only a small part of COD was removed regardless of SRT. Physical characteristics of the electrode as porosity, roughness and the electrode area density and the biocompatibility of the electrode are key factors to increase the performance of CCM. The carbon felt was the best studied material having the highest values of porosity, roughness and the electrode area density.
22

Récupération d'énergie issue des déformations de structures aéronautiques à l'aide de matériaux piézoélectriques

Debeaux, Sébastien January 2012 (has links)
Résumé: La maintenance des structures aéronautiques (fuselage, ailes) est une opération majeure très onéreuse. Elle requiert l'immobilisation des appareils ainsi que le démontage de certaines de leurs parties afin de procéder à leur inspection. Pour permettre une surveillance in situ, des capteurs et actionneurs ont peu à peu été intégrés aux structures aéronautiques. L'utilisation de capteurs et actionneurs sans fil est attirante du fait qu'elle n'implique pas de câblage des noeuds (gain de poids et de coût). Ces noeuds doivent néanmoins être auto-alimentés afin d'être réellement viables_ L'idée est donc de convertir l'énergie mécanique (vibrations) disponible dans les structures d'avions en électricité en utilisant des matériaux piézoélectriques. Les travaux effectués dans ce mémoire permettent d'évaluer le potentiel des récupérateurs d'énergie basés sur les déformations (différents des récupérateurs inertiels) pour alimenter des noeuds sans fil embarqués sur des structures d'avions. Pour cela, des modèles simples sont utilisés pour décrire le comportement dynamique typique des parties de l'avion : une poutre représente l'aile soumise à des charges aérodynamiques et une plaque représente un panneau de fuselage soumis à des champs de pression (bruit de jet et couche limite turbulente). Des matériaux piézoélectriques aussi différents que le PZT monolithique, le composite piézo-fibres et le Polyfluorure de Vinylidêne (PVDF) sont testés dans le but d'évaluer l'influence de leurs caractéristiques (taille, polarisation, capacité, forme des électrodes...) sur la puissance électrique récupérée. Les résultats montrent que pour une excitation aéronautique typique de la poutre (10 Hz et 56 udef), l'énergie produite est de l'ordre de 40 mi pour le PZT monolithique pour une durée de charge de 7 minutes. D'après la littérature, cette énergie est suffisante pour faire des transmissions RF (25 pi). Mais pour d'autres types d'excitations (par exemple le buit de bruit de jet des réacteurs d'avion), il faudra 25 minutes pour produire une énergie de 1 mJ pour le même type de piézoélectrique. L'inconvénient est qu'il faudra attendre de nombreuses secondes avant de charger la batterie du récupérateur d'énergie. Si l'on considère que plusieurs autres organes devront consommer de l'énergie en parallèle, le temps en chaque cycle pourra être de plusieurs minutes. Par conséquent, les récupérateurs d'énergie basés sur les déformations peuvent être utilisés pour alimenter des nœuds sans fil même s'ils ne permettent pas des mesures en temps réel. Cependant, cette approche est une manière simple et pratique de collecter de l'énergie que les autres types de récupérateurs (inertiel, solaire...) puisqu'elle nécessite seulement le collage du matériau piézoélectrique sur la surface vibrante. Enfin, il en ressortira des conseils de dimensionnement pour ce type de récupérateur afin d'en optimiser l'utilisation à partir d'une excitation donnée.||Abstract: Aerospace structural maintenance (fuselage, wings) is a major component of operational costs which requires aircraft to be grounded and some of its parts to be dismantled in order to proceed to inspection. In order to allow in situ monitoring, Structural Health Monitoring (SHM) has been proposed where sensors and actuators are integrated on the structure. To avoid extensive wiring of the nodes, wireless sensors and actuators are attractive but should be self powered to fully benefit from them. One idea is to convert the mechanical energy (vibrations) available all over an aircraft into electricity using piezoelectric materials. This work investigates the potential of strain-based energy harvesters (as opposed to inertial harvesters) to supply wireless nodes on typical aircraft structures. A simple model is used to describe typical dynamic behavior of aircraft components: a beam representing the whole wing subjected to aerodynamic loading and a plate representing a fuselage panel subjected to pressure fields (jet noise and turbulent boundary layer). Various configurations of piezoelectric materials are tested such as bulk PZT, PZT fiber composite and Polyvinylidene Fluoride (PVDF) in order to evaluate the influence of their characteristics (size, polarization, electrodes' shape, capacitance...) on the harvested power. The results show that for a typical aerospace excitation of the beam (10 Hz and 56 mudef), the energy produced is up to 40 mJ with bulk PZT for a 7 minutes loading time. From the literature, this appears sufficient for RF transmission (25 muJ). For other excitation sources (for instance jet noise), the energy produced is up to only 1 mJ with bulk PZT for a 25 minutes loading time. The drawback is that we should wait for several seconds in order to charge the harvester's battery. And, considering that many other components than the RF transceiver will require energy in the meantime, the time laps between two' measures could increase to several minutes. Therefore, strain-based energy harvester could be used for supplying wireless sensor nodes but they would not allow real time measurement. However this approach is a simple and convenient way to scavenge energy compared to other kinds of harvesters (inertial, solar...) since it amounts to bonding a piezoelectric material on a flexible surface. Some design advices are eventually proposed for this kind of harvesters. They could be used for designing a harvester able to produce desired power from a known excitation.[symboles non conformes]
23

Graphics Editor

Zhao, Die January 2007 (has links)
<p>The human enters into the information age in 21st century; the computer science and technology are developed at full speed, and already infiltrate into various field extensively. Resultantly manual drawing gradually is phased out, for those designers who have no prior experience in the computer operation are concerned, they need to have a kind of two-dimensional graphical tool. Graphics editor system arose to the request for designing planar figures for people who have little knowledge in computer.</p><p>This paper describes the development process of this system what is studied for the foundation, utilize object-oriented method to analyze, design with computer figure, and adopt Visual C ++ 6.0 as the developing platform. All these have been finished after 1 month or so. It designs to be two-dimensional graphical software with diverse function which operates simply, easy to study, mutual interface friendly graphics editor system and has satisfied some figure users at present with the new demand as well.</p><p>The following main functions have been realized in this application: It can draw various figures, such as dot, line, circle, arc, parabola and curve, modify them and comprehensive editing. Figure editor includes translation, mirroring, rotating and some similar operations. Comprehensive drawing includes drawing polygon (sealed and arbitrary polygon), round tangent line, round circle contact, line circle contact, some circle contacts and so forth. Meanwhile obtain the point of intersect between the arbitrary crossing, and draw different figures basically according to the points of intersect. By the way, it is capable to cancel and redraw the editing.</p>
24

Analysis of metatranscriptomes from an acidophilic electricity generating community treating acidic mining wastewaters

Palma, Daniela January 2018 (has links)
Human ́s constant need for metals requires unsustainable mining and refining of metalore. As a result, highly contaminated wastewaters are discharged in the environmentcompromising the nearby habitat together with all its life forms. Microbial fuel cells arebioelectrochemical systems (BES’s) that use microorganisms to convert organic andinorganic matter, producing electricity as the final product. This technology has shownto have great potential for application for bioremediation of wastewaters. This thesisdescribes the gene expression and the taxonomical abundance of an acidophilic,electricity generating community that was used to treat mining wastewaters in amicrobial fuel cell. A complete metatranscriptomics analysis has been performed onduplicate MFC anode acidophilic microbial community generating electricity frominorganic sulfur compounds (ISC) oxidation at extremely low pH. The analysis showsthat the most expressed genus is Ferroplasma-like, the genus Acidithiobacillus-like isfollowing along with Sulfobacillus-like and Thermoplasma-like. Some of the generaexpressed show behaviours never described before suggesting that potentially, newspecies have been selected. The reactions of the sulfur pathway are regulated mostly bytwo genera: Acidithiobacillus-like during the disproportionation of tetrathionate, andFerroplasma-like by expressing the hdr gene that catalyses the reaction from elementalsulfur to sulfite, the sulfite is then converted to sulfate. The hdr gene has not previouslybeen found in F. acidarmanus-like suggesting that the specie might have been selectedfor this trait. Acidithiobacillus-like genus has a bigger role for the energy conservationand the electron transport in the sample, however the data are not sufficient to point outwhich gene has the major role in the process. The CO2 fixation in the chamber wasconsiderably low as a result from a significant carboxysomes production, bacterialcompartiments involved in the carbon dioxide fixation. The transcripts abundanceregarding the metal resistance genes have shown low expression suggesting that thecells were not under stress. This result is indicated by the synthesis of a transcriptionalrepressor protein that had prevented a significant production of metal resistanceenzymes. Likewise, the pH homeostasis plot does not show vast transcripts abundances,indicating that the cells were thriving under conditions not far from the optimum.
25

Novel oil resistant cellulosic materials

Aulin, Christian January 2009 (has links)
The aim of this study has been to prepare and characterise oil resistant cellulosic materials, ranging from model surfaces to papers and aerogels. The cellulosic materials were made oil resistant by chemical and topographic modifications, based on surface energy, surface roughness and barrier approaches. Detailed wetting studies of the prepared cellulosic materials were made using contact angle measurements and standardised penetration tests with different alkanes and oil mixtures. A significant part of the activities were devoted to the development of model cellulosic surfaces with different degrees of crystalline ordering for the wetting studies. Crystalline cellulose I, II and amorphous cellulose surfaces were prepared by spin-coating of cellulose nanocrystal or microfibrillated cellulose (MFC) dispersions, with Langmuir-Schaefer (LS) films or by a layer-by-layer (LbL) deposition technique. The formation of multilayers consisting of polyethyleneimine (PEI)/anionic MFC or cationic MFC/anionic MFC was further studied and optimized in terms of total layer thickness and adsorbed amount by combining Dual Polarization Interferometry (DPI) or Stagnation Point Adsorption Reflectrometry (SPAR) with a Quartz Crystal Microbalance with Dissipation (QCM-D). The smooth cellulosic surfaces prepared had different molecular and mesostructure properties and different surface energies as shown by X-ray diffraction, Atomic Force Microscopy (AFM) imaging, ellipsometry measurements and contact angle measurements. The cellulose model surfaces were found to be ideal for detailed wetting studies, and after the surface has been coated or covalently modified with various amounts of fluorosurfactants, the fluorinated cellulose films were used to follow the spreading mechanisms of different oil mixtures. The viscosity and surface tension of the oil mixtures, as well as the dispersive surface energy of the cellulose surfaces, were found to be essential parameters governing the spreading kinetics. A strong correlation was found between the surface concentration of fluorine, the dispersive surface energy and the measured contact angle of the oil mixtures. Silicon surfaces possessing structural porous characteristics were fabricated by a plasma etching process. The structured silicon surfaces were coated with sulfate-stabilized cellulose I nanocrystals using the LbL technique. These artificial intrinsically oleophilic cellulose surfaces were made highly oleophobic when coated with a thin layer of fluorinated silanes. By comparison with flat cellulose surfaces, which are oleophilic, it is demonstrated that the surface energy and the surface texture are essential factors preventing oil from spreading on the surface and, thus, inducing the observed macroscopic oleophobic properties. The use of the MFC for surface coating on base papers demonstrated very promising characteristics as packaging materials. Environmental-Scanning Electron Microscopy (E-SEM) micrographs indicated that the MFC layer reduced the sheet porosity, i.e. the dense structure formed by the nanofibers resulted in superior oil barrier properties. Attempts were made to link the procedure for preparation of the MFC dispersions to the resulting microstructure of the coatings, and film porosity and the film moisture content to the resulting permeability properties. Finally, MFC aerogels were successfully prepared by freeze-drying. The surface texture of the porous aerogels was carefully controlled by adjusting the concentration of the MFC dispersion used for the freeze-drying. The different scales of roughness of the MFC aerogels were utilised, together with the very low surface energy created by fluorination of the aerogel, to induce highly oleophobic properties. / QC 20100623
26

The Visualization and Shadow Analysis for 3D Geographic Objects

Li, Yu-Cheng 17 August 2007 (has links)
3D GIS is the key point of the development in the area in geospatial information domain. 3D visualization techniques, including 3D terrain data processing, the 3D objects modelling , satellite or air photo image texture, model material, level-of-detail terrain, is already gradually mature and had the outstanding performance in the existing 3D GIS software. But 3D spatial analysis function was still lacking in the field of the 3D spatial data processing. The goal of this research is to develop a 3D spatial analysis function for sun shadow in horizontal and vertical direction and to construct a system for 3D geographic objects visualization by using MFC and OpenGL as the development kit. It has some fundamental functions including: camera control, selecting a single face of a object, linking to a database, level-of-detail terrain. The shadow volume algorithm was used for 3D shadow visualization, and light tracing algorithm was used to compute a single face¡¦s culling area, finally sunshine formula of four seasons was utilitized to realize the shadow analysis function.
27

Utveckling av programvara för inrapportering av vägstatus och utrustning längs med vägar

Björk, Johan January 2010 (has links)
No description available.
28

Build an Inventory Tracking System

Zou, Hanzheng January 2007 (has links)
<p>This thesis paper introduces you about the process of how to build an inventory tracking system in a local Swedish company. The related project is to support the thesis paper, and is also for the company’ using. The software product of this project is an application that works for managing various types’ instruments in the company of SWECO-Vaxjo. It will play an important role in the further management work of the company.</p><p>In this thesis paper, the candidate techniques and theories for implementing this system are discussed. And in the end a good solution for this problem will be presented in the paper.</p>
29

Konfigurationsverktyg för spänningslikriktare

Wallgren, Martin, Sandberg, Robert January 2005 (has links)
<p>Kraftelektronik AB i Växjö tillverkar en spänningslikriktare som kan konfigureras enligt kundens önskemål. Antalet parametrar som kan ändras uppgår till över 300 stycken och måste i nuläget konfigureras manuellt av en operatör.</p><p>För att förenkla önskade de att vi utvecklade ett program så konfigurationen kunde utföras i Windows-miljö.</p> / <p>Kraftelektronik AB in Växjö manufactures a power rectifier which can be configured according to a customer’s wish. The number of parameters which can be changed reach above 300 and must today be configured manually by an operator.</p><p>To simplify they wished that we developed a program so the configuration could be carried out in a Windows environment.</p>
30

Ανάπτυξη καινοτόμου διεργασίας κυψελίδας καυσίμου για την ενεργειακή αξιοποίηση υγρών αποβλήτων

Τρεμούλη, Ασημίνα 01 August 2014 (has links)
Η μικροβιακή κυψελίδα καυσίμου (ΜΚΚ) είναι ένας βιοαντιδραστήρας ο οποίος μετατρέπει απευθείας τη χημική ενέργεια ποικίλων υποστρωμάτων σε ηλεκτρική ενέργεια μέσω μικροβιακών καταλυτικών αντιδράσεων, σε αναερόβιες συνθήκες. Η διττή υπόστασή της τεχνολογίας να επεξεργάζεται λύματα με ταυτόχρονη παραγωγή ηλεκτρικής ενέργειας, έχει κερδίσει τα τελευταία χρόνια το ενδιαφέρον της επιστημονικής κοινότητας. Η παρούσα διδακτορική διατριβή προτείνει μια πρωτότυπη ΜΚΚ ενός θαλάμου ιδιαίτερης αρχιτεκτονικής, η οποία συνδυάζει πληθώρα πλεονεκτημάτων. Τα πειράματα που διεξήχθησαν είχαν ως απώτερο στόχο τη βελτιστοποίηση τόσο των σχεδιαστικών όσο και των λειτουργικών παραμέτρων της κυψελίδας, η οποία μελετήθηκε κάτω από το πρίσμα της εφαρμογής της σε μονάδες βιολογικού καθαρισμού αστικών λυμάτων. Η λογική που εργάστηκα βασίστηκε στη λειτουργία της συσκευής με πλήρη αντικατάσταση των ακριβών υλικών από φθηνότερα, ενώ ταυτόχρονα προσπάθησα σταδιακά να βελτιώσω την απόδοσή της, ακόμα και σε λειτουργίες μακράς διαρκείας. Η καινοτόμος κυψελίδα λειτούργησε σε συνθήκες διαλείποντος και συνεχούς έργου. Παράλληλα, με τη λειτουργία της καινοτόμου διάταξης, μελετήθηκε η επίδραση διαφορετικών παραμέτρων στην απόδοση ΜΚΚ δύο θαλάμων (τύπου H). Η εμπειρία που αποκτήθηκε από την προκειμένη λειτουργία, καθώς και τα αποτελέσματα των πειραμάτων αυτών, είναι πρωταρχικής σημασίας, καθώς αποτέλεσαν τον οδηγό για την καινοτόμο κατασκευή και τη λειτουργία της ΜΚΚ ενός θαλάμου. Έτσι λοιπόν, στα πλαίσια της παρούσας έρευνας μελετήθηκαν τόσο συνθετικά (γλυκόζη, πεπτόνη από χωνευμένο με τρυψίνη κρέας και αραβοσιτέλαιο) όσο και πραγματικά απόβλητα (ορρός τυρογάλακτος, αστικό λύμα). Ειδικότερα, μελετήθηκαν οι παράμετροι της ιοντικής ισχύος, του pH, του είδους του αποδέκτη ηλεκτρονίων, της θερμοκρασίας, της αρχικής συγκέντρωση του υποστρώματος, του υδραυλικού χρόνου παραμονής (HRT), της επιφάνειας του ανοδικού ηλεκτροδίου αλλά και της ποσότητας του καταλύτη της καθόδου. Επιπρόσθετα, προκειμένου να επιτευχθεί πλήρης ηλεκτροχημικός χαρακτηρισμός των κυψελίδων, διεξήχθηκαν πειράματα Φασματοσκοπίας Ηλεκτροχημικής Εμπέδησης (Electrochemical Impedance Spectroscopy, EIS) ενώ παράλληλα ελήφθησαν ηλεκτρονικές μικρογραφίες των ανοδικών ηλεκτροδίων με ηλεκτρονικό μικροσκόπιο σάρωσης (SEM). Τέλος, στα πλαίσια αξιοποίησης των πειραματικών αποτελεσμάτων της παρούσας διατριβής το μαθηματικό μοντέλο των Zeng et al τροποποιήθηκε κατάλληλα ώστε να καταστεί δυνατή η περιγραφή των αποτελεσμάτων της ΜΚΚ δύο θαλάμων. / A microbial fuel cell (MFC) is a bioreactor that converts the chemical energy of the bonds of organic compounds to electrical energy, through the catalytic reactions of microorganisms under anaerobic conditions. Over the last years the MFC technology has gained increasing interest from the scientific community, because it offers the advantage of simultaneous wastewater treatment and electricity generation. The present thesis proposes an innovative single chamber MFC design of a special architecture, which combines several advantages. The aim of the experiments was to optimise the design and the operational parameters of the proposed MFC, under the view of its practical implementation at wastewater treatment plants. In order to accomplish this goal the cost was kept low, by replacing all the expensive materials with lower-cost ones, while gradually increasing the cell performance even during long term operation. The MFC was operated both in batch and continuous mode. In parallel with single chamber MFC operation, the effects of several parameters on the performance of a dual chamber MFC (H-type) were examined. The findings from these experiments as well as the experience gained are of great significance, because they were used as guides for the construction and operation of the prototype cell. In conclusion, during the present research, synthetic (glucose, peptone, trypsin from meat digested and corn oil) as well as real wastewater (cheese whey, domestic wastewater) were examined. Specifically, the ionic strength, pH, the type of electron acceptor, the temperature, the initial substrate concentration, the Hydraulic Retention Time (HRT), the surface area of the anodic electrode as well as the quantity of the cathode catalyst were tested. Additionally, aiming at a detailed electrochemical characterization of the MFCs, the impedance characteristics were also investigated by performing Electrochemical Impedance Spectroscopy (EIS) experiments, while Scanning Electron Microscopy (SEM), images of the anodic biofilm were collected. Finally, for the valorization of the experimental results of the present thesis, the mathematical model of Zeng et al was appropriately modified in order to describe the experimental results of the dual chamber MFC.

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