This thesis focuses on the design of an electrical drive system for the purpose of high precision motion control. A modern electrical drive is usually equipped with a current regulated voltage source along with powerful motion controller system utilizing one or more micro-controllers and/or digital signal processors (DSPs). That is, the motor drive control is mostly performed by a dedicated digital-motion controller system. Such a motor drive mostly interfaces with its host processor via various serial communication protocols such as Profibus, CAN+, RS-485 etc. for the purpose of receiving commands and sending out important status/control signals. Considering that the motor drives lie at the heart of every (multi-axis) motion control system, the aim of this thesis is to explore the design and implementation of a conventional DC motor drive system suitable for most industrial applications that require precision and accuracy. To achieve this goal, various underlying control concepts and important implementation details are rigorously investigated in this study. A low power DC motor drive system with a power module, a current regulator and a motion controller is built and tested. Several design revisions on these subsystems are made so as to improve the overall performance of the drive system itself. Consequently, important &ldquo / know-how&rdquo / required for building high performance (and high power) DC motor drives is gained in this research.

The objective of this research is to determine if it is possible to reduce the number of organic solar cells required to power a load using a DC to DC converter thereby reducing the cost of the organic solar array system. An organic solar power system designer may choose an organic implementation of a DC to DC converter to go along with the organic solar cell array. Common DC to DC converters include the buck converter, boost converter, buck/boost converter, and Cuk converter, all of which are not good candidates for organic implementation due to their use of inductors. Organic inductors are relatively more lossy than organic capacitors. So, an inductor-less DC to DC converter, such as the Dickson charge pump, would be a better candidate for organic implementation. Solar cells connected in an array configuration usually do not perform up to their full potential due to current and voltage mismatches between solar cells. These mismatches can be related to each solar cell's circuit model parameters such as the photon current density, diode ideality factor, diode reverse saturation current density, parallel resistance, and series resistance. This research varies these circuit model parameters as dependent variables, and observes the loads and power levels that make the Dickson charge pump a feasible option. The results show that current mismatch does produce an opportunity to use a DC to DC converter to save the use of a few solar cells. However, the Dickson charge pump was found to be infeasible due to an input voltage requirement that could not be met using the tested organic solar cells.

Η παρούσα διπλωματική εργασία πραγματεύεται το σχεδιασμό και την κατασκευή διάταξης φόρτισης του κινητήρα ενός ηλεκτροκίνητου οχήματος. Η εργασία αυτή εκπονήθηκε στο Εργαστήριο Ηλεκτρομηχανικής Μετατροπής Ενέργειας του Τμήματος Ηλεκτρολόγων Μηχανικών και Τεχνολογίας Υπολογιστών της Πολυτεχνικής Σχολής του Πανεπιστημίου Πατρών. Κύριος σκοπός της διπλωματικής εργασίας είναι η κατασκευή ενός αμφίδρομου ηλεκτρονικού μετατροπέα ισχύος, που θα ελέγχει μια μηχανή συνεχούς ρεύματος ξένης διέγερσης, η οποία συνδέεται μέσω ενός συστήματος μετάδοσης με τον κινητήρα ενός ηλεκτροκίνητου οχήματος. Απώτερος στόχος είναι η εξομοίωση όλων των πιθανών φορτίων που ασκούνται σε έναν κινητήρα κατά την κίνηση του οχήματος. Αρχικά αναλύεται το φορτίου του κινητήρα κατά την κίνηση του οχήματος και αναζητούνται τρόποι για την εξομοίωση και τη σύνδεση των εξωτερικών δυνάμεων που ασκούνται στο όχημα με τη ροπή της μηχανής. Στη συνέχεια αναλύθηκε ο αμφίδρομος ηλεκτρονικός μετατροπέας που χρησιμοποιήθηκε για τον έλεγχο της μηχανής συνεχούς ρεύματος και αναζητήθηκαν οι κατάλληλες μέθοδοι για τον έλεγχο του συγκεκριμένου μετατροπέα. Το επόμενο βήμα ήταν η προσομοίωση του συνολικού συστήματος φόρτισης προκειμένου να εξακρθωθεί η ορθή λειτουργία του πριν την κατασκευή, με χρήση του λογισμικού MATLAB/SIMULINK. Τέλος, μελετάται και κατασκευάζεται στο εργαστήριο η πειραματική διάταξη, με τη χρήση της οποίας διεξάγονται οι μετρήσεις για την επιβεβαίωση και την αξιολόγηση της θεωρητικής μελέτης. / This thesis discusses the design and manufacture of a charging device intended for an electric vehicle motor. The work was conducted in the Laboratory of Electromechanical Energy Conversion, Department of Electrical and Computer Engineering, School of Engineering, University of Patras. The main purpose of this thesis is to manufacture a bidirectional electronic power converter able to control a DC motor which is connected with the engine of an electric vehicle via a transmission system. The ultimate goal is to simulate all possible loads exerted on a motor during the vehicle movement. Initially we analyze the load on the engine during vehicle movement and seek ways to simulate and combine the external forces acting on the vehicle with the engine torque. In the sequel the bidirectional electronic power converter used to control the DC motor is analyzed and appropriate control methods are investigated. The next step is to simulate and validate the overall system functionality using MATLAB / SIMULINK, before actually proceeding with the manufacture. Finally, an experimental setup is prepared in our lab, the results of which are utilized to confirm and evaluate the aforementioned theoretical study.

Dans le but de gérer la consommation et ainsi que la production efficace des énergies renouvelables, l’utilisation et augmentation de l’efficacité des systèmes de conversion d’énergie est devenue indispensable. Dans ce contexte, les transistors en nitrure de gallium (GaN HFETs) pour une densité de puissance commutée très importante, offrent des nouvelles possibilités et ils tirent vers le haut la gestion efficace des énergies renouvelables. Toutefois, cette nouvelle possibilité passe par un pilotage efficace des composants et une encapsulation et des interconnexions optimales. Ces travaux de thèse étudient et analyse les avantages et inconvénients d'une nouvelle structure de conversion multi cellulaire et ceux d’un driver spécifique multivoies monolithique et synchronisé pour les composants GaN, appliqué dans ce contexte précis. Ce manuscrit de thèse est composé de quatre chapitres. Après une étude bibliographique, le positionnement du convertisseur DAB (Dual Active Bridge) parmi les autres structures de conversion DC à l’aide d’une nouvelle méthodologie de comparaison (FOM topologique – Figure de Mérite) est présenté dans le premier chapitre. Afin de diminuer les contraintes de conversion d’énergie, une étude est amenée dans le chapitre 2 sur les principaux défis et enjeux d’une solution générique à travers de réalisation d’un réseau de convertisseurs. Le chapitre 3 présente la partie importante d’expérimentation et d’optimisation de la cellule élémentaire à base de convertisseurs DAB des points de vue fonctionnels mais aussi et surtout structurels. L’étude de l’isolation galvanique de la structure de conversion DAB reste l'objectif principal à développer pour démontrer le potentiel de remplacer le transformateur par une isolation capacitive. La conception de la puce de commande dédiée aux nouveaux transistors GaNs, les résultats pratiques des performances sont présentés dans le dernier chapitre. Certaines comparaisons du driver QGD (Quad Gate Driver) avec les autres solutions de transfert d’ordres de commande sont également discutées. La mise en œuvre du circuit de commande dans un convertisseur DAB afin de valider le fonctionnement de QGD est introduite dans les perspectives. / In order to improve the management and the production efficiency in renewable energy, power electronics systems have become important contributors. In this context, gallium nitride transistors (GaN HFETs) provide new opportunities for high power density, high switching speed and they pull up the effective management of renewable energies. However, this new opportunity requires effective gate drivers and optimal packaging and assembly. This thesis will introduce the general approach of a new architecture for multi cellular conversion and a monolithic multichannel and synchronized drive for GaN components, which are applicable in our specific context. This thesis is composed of four chapters. A bibliographic section is presented in first chapter. A new comparative methodology has been developed in this chapter in order to benchmark the DAB (Dual Active Bridge) converter with respect to other DC converters. In the second chapter, a generic solution (converter grid) has been explained in order to reduce the energy conversion constraints. Chapter 3 presents the important parts of the experimentation and the optimization of DAB converter. High frequency transformer replacing by capacitors is the main objective of this section. The design of the Quad Gate Driver (QGD) IC dedicated to GaNs transistors control in H bridge configuration and the results of their performances are presented in the last chapter. Some comparisons of this approach with other signal transfer solutions are also discussed. The implementation of the QGD in a full bridge transistor converter is introduced into the perspective section.

La tendance actuelle vers la miniaturisation des circuits électroniques a poussé vers ledéveloppement des systèmes sur puce (SoC : System on Chip) contenant plusieurs composants. Cescomposants réalisant des fonctions variées, ont besoin de différentes tensions d’alimentation fourniesà l’aide de plusieurs convertisseurs DC/DC connectés à l’alimentation du SoC. Actuellement, laplupart des circuits électroniques dans les applications portables contiennent des convertisseursDC/DC conventionnels utilisant une inductance pour stocker transitoirement l’énergie électrique.L’inductance étant un composant passif difficilement intégrable, ces convertisseurs sontconnectés à l’extérieur de la puce. Une alternative aux convertisseurs conventionnels est leconvertisseur à capacités commutés, qui a l’avantage d’être facilement intégrable sur silicium.Toutefois, il présente des limitations à cause de la dépendance du facteur de conversion avec lenombre de condensateurs. De plus, les pertes inhérentes à la charge et à la décharge descondensateurs font diminuer son rendement. Il est donc intéressant de trouver une nouvellealternative pour concevoir un convertisseur DC/DC compact et performant afin d’obtenir un circuitélectronique complètement intégrable sur silicium.Le sujet de cette thèse répond au besoin d’une nouvelle méthode de conversion DC/DCintégrable sur silicium et à haut rendement. L’idée est d’utiliser une capacité variable mécaniquementà la place d’une inductance pour stocker l’énergie électrique transitoire. Le condensateur variable serafabriqué par des procédés de fabrication de microsystème MEMS sur silicium ce qui permet d’intégrerla totalité du convertisseur.Dans ce mémoire, nous expliquons tout d’abord le principe et le fonctionnement d’un abaisseur etd’un élévateur de tension utilisant notre nouvelle approche. Par la suite, nous présentons laconception et la fabrication d'un MEMS adapté à la conversion de tension. Finalement, nousexpliquons notre méthode de contrôle utilisant une commutation à zéro de tension. Le rendement d'unélévateur 10V-20V obtenu par simulation est de l’ordre de 88% lorsque la gestion électrique estréalisée avec des composants discrets. Ce rendement très prometteur, devrait être amélioré dans lefutur lorsque tout le système sera intégré sur silicium. / Current trends towards miniaturization of electronic circuits had led to the advent of System onChip containing different types of circuits indented to perform different functions. These sub-systemsrequire different supply voltages that are delivered from the SoC supply voltage using several DC/DCconverters. Currently, most of the electronic circuits of portable applications use conventional SMPS(switch mode power supply) DC/DC converters containing an inductor element to stock temporally theelectrical energy.In this case the converter is outside the chip since the integration of the inductor is very difficultand that resistive losses increase when the coil diameter decreases. The alternative to use switchedcapacitor converters, which can be easily integrated on silicon, presents some limitations because ofthe dependence of the required number of capacitors on the conversion ratio, and because ofswitching losses due to the charge and the discharge of the capacitors inducing a decrease of theconversion efficiency. For that reason, it is interesting to develop a new alternative that allows thefabrication of a compact and efficient DC/DC converter in order to get a completely integrated system.This thesis focuses on a novel solution based on electrostatic MEMS in order to make anintegrated DC/DC converter with high efficiency. A mechanically variable capacitor is used instead ofthe inductor element to store the transient electrical energy. The variable capacitor is fabricated byMEMS micromachining process techniques compatible with CMOS process integration.In this work, we explain the principle and the operation of a step down and a step-up converterusing our novel approach through an energetic analysis, we design a MEMS device optimized withrespect to the voltage conversion application, and we present our converter control method using azero voltage switching technique. An efficiency of almost 88% was obtained by simulation of a 10V-20V converter, when the power management circuitry was considered with discrete elements; thisefficiency is promising and could be improved when the whole system will be integrated on silicon.:

Les convertisseurs de puissance en DC/DC sont largement utilisés pour les applications domestiques et industrielles pour des puissances de quelques Watts à quelques MégaWatts. Généralement, pour chaque application un convertisseur adapté est conçu afin de répondre au cahier des charges. A chaque nouvelle application correspond donc un nouveau convertisseur, ce qui conduit à concevoir systématiquement de nouvelles structures de conversion et qui s'avère coûteux en temps et en argent. Eventuellement, cela peut conduire à des développements technologiques spécifiques qui, eux aussi ont des conséquences sur le coût de développement des solutions d'électronique de puissance.Afin de contourner ces difficultés, mes travaux de thèse portent sur la démarche Réseaux de Micro Convertisseurs (RµC) qui propose une nouvelle approche permettant de répondre de manière totalement flexible à n’importe quel cahier des charges. Cette approche vise à créer un composant unique, appelé cellule élémentaire (CE), permettant de répondre à tout type de cahiers des charges par la mise en série et/ou en parallèle de plusieurs de ces cellules élémentaires. Elle permet ainsi de régler les calibres en tension et/ou en courant du convertisseur à réaliser. Mes travaux de thèse se divisent en deux grandes parties. La première partie consiste en la conception et l’intégration de la cellule élémentaire utilisée dans le RµC. La deuxième, aborde les stratégies de configuration utilisées dans les RµC ainsi que les modes d’association des cellules élémentaires pouvant répondre à n’importe quel cahier des charges. / DC/DC power converters are widely used for domestic and industrial applications with powers from a few watts to several MegaWatts. Generally, for each application, an appropriate converter is designed to meet the specifications. So, with a new application corresponds a new converter leading to systematic review and re-design of a new structure of conversion which is costly in time and money. Eventually, it can lead to specific technological developments which also have an impact on the cost of developing solutions for power electronics. To circumvent these difficulties, my thesis focuses on the process of Micro Converters Networks (MiCoNet) which proposes a new approach to respond fully flexibely to any specifications. The aim of this approach is to create a unit component, called elementary cell, able to respond to any kind of specifications by connecting in series and/or parallel several of these elementary cells. It permits to adjust the voltage and/or current of the converter to achieve. Therefore, my thesis is divided into two main parts. The first part consists in the design and the integration of the elementary cell used in the MiCoNet. The second discusses the configuration strategies used in the MiCoNet and association modes of elementary cells which can respond to any specification.

This study is an analysis of the changes to the institutions and doctrines of French development aid between 1998 and 2002, and specifically the reforms announced by Prime Minister Jospin in February 1998. This includes analysis of institutional reorganisation and of new policy doctrines. The study considers the implications of these changes for the relations between France and former French colonies of sub- Saharan Africa, including detailed analysis of the aid relationship between France and Cote d’Ivoire. Using qualitative data, especially personally conducted interviews in Paris and Côte d’Ivoire and analysis of official documents, this is the first major study of these reforms that puts them into historical and theoretical perspective. It thereby contributes to the wider debate over continuity and change both in French aid policy and in France’s relations with sub-Saharan Africa. It also furthers understanding of the mechanisms and dynamics of reform within French state administration. This study compares French development aid policy and institutional architecture from the 1960s up to the mid 1990s with the new institutions and policies put in place in the 1998–2002 period. Chapter 1 looks at the creation of French aid policy in the late 1950s and early 1960s and considers its imperial origins. Chapter 2 examines French aid from 1960 to 1995 and places it in the context of the global politics of development aid and the policies of other donors, in order to highlight the specificities of the French case. The French reaction to the emergence of the structural adjustment and later good governance agendas is considered. Chapter 3 examines the content of the reforms put in place by Jospin and associated changes in the 1998–2002 period, including the reactions of officials and critics. Chapter 4 is a case study of the changes made to the aid relationship between France and Cote d’Ivoire and the effects of instability in Côte d’Ivoire on French policy. The impact on French policy of the growing role of multilateral donors in Côte d’Ivoire is also considered. Chapter 5 examines the evolutions in French doctrine which have run in parallel to the Jospin reforms, looking at French attitudes to major development issues, particularly the relationship between the state and the market. French development aid is part of the long-term continuities of French foreign policy, and especially France’s desire to demonstrate the universal validity of its cultural and political achievements. In this study French aid is analysed as an extension of these foreign policy aims within the specific post-colonial relations with sub-Saharan Africa. French aid has helped to maintain a protected environment within which the French have sought not only to support close political allies, but also to reproduce a “model” of society and politics. This study asks whether the French can continue to use aid in this way in the light of the Jospin reforms and the events of the 1998–2002 period. This study asks whether the changes of this period can be seen as a convergence between French aid and the policies, practices and norms of other aid donors. To this end, the notion of an aid donor “regime” is used. This helps to show that reform of French policy occurs in a context of interaction with other aid donors, and to show how that interaction affects French policy

BRITO, M.S. Avaliação do potencial antioxidante e citotóxico das partes do fruto de cereus jamacaru dc, cactaceae. 2015. 77 f. Dissertação (MESTRADO EM BIOTECNOLOGIA) - Campus de Sobral, Universidade Federal do Ceará, Sobral, 2015. / Submitted by Djeanne Costa (djeannecosta@gmail.com) on 2017-09-01T12:49:14Z No. of bitstreams: 1 2015_dis_msdbrito.pdf: 3010290 bytes, checksum: d07bcc4575585e471bc44956632f673d (MD5) / Approved for entry into archive by Djeanne Costa (djeannecosta@gmail.com) on 2017-09-27T15:27:59Z (GMT) No. of bitstreams: 1 2015_dis_msdbrito.pdf: 3010290 bytes, checksum: d07bcc4575585e471bc44956632f673d (MD5) / Made available in DSpace on 2017-09-27T15:27:59Z (GMT). No. of bitstreams: 1 2015_dis_msdbrito.pdf: 3010290 bytes, checksum: d07bcc4575585e471bc44956632f673d (MD5) Previous issue date: 2015 / Cacti are resistant plants during dry periods, among which is included the Cereus jamacaru, known as mandacaru. The mandacaru is a common columnar cactus in Brazil that produces an edible, red, fleshy fruit, with white flesh and small seeds. The fruits to providing essential nutrients and they also produces active ingredients with biological properties such as antioxidant activity. The main objective of the study was to evaluate the antioxidant potential, cytotoxicity and verify the chemical composition of parts of the fruit of Cereus jamacaru DC, aimed at encouraging the consumption and the industrial use of the fruit. Parts of the fruit were separated (peel, pulp and seeds) and made extraction with ethanol 70% and 95%, resulting in six samples: peel (CM70% and CM95%) pulp (PM70% and PM95%) and seeds (SM70% and SM95%). The antioxidant activity was evaluated through sequestration method free radical DPPH (2,2-diphenyl-1-picrilhidrazila). The six samples were tested in concentrations of 100 to 2000 μg mL-1. The positive controls were eugenol and β-carotene. We calculated the percentage of antioxidant activity (AA%) and the Efficient Concentration (EC50). The kinetic profile was determined by the reduction of DPPH with respect to time. The chemical characterization of the samples was performed by infrared spectroscopy (FTIR). The cytotoxicity was determined by MTT assay on macrophages. With the data obtained by infrared, it was found that the six samples show different antioxidant compounds. The peel samples showed AA% values higher than β-carotene in all tested concentrations. Already the SM70% and SM95%% exhibited the highest AA%, with antioxidant activity similar to eugenol in concentrations above of 400 μg mL-1. The samples exhibited three kinetic profiles: fast for SM70%, SM95%, and CM70%; intermediate for the CM95% and slow for PM70% and PM95. The lower EC50 values were observed in seeds and peel samples: SM70% (0,233 mg mL-1) SM95% (0,217 mg mL-1); CM70% (0,56mg mL-1), and CM95% (0.94 mg mL-1). The highest EC50 values were observed in pulp samples: PM70% (10.95 mg mL-1) and PM95% (8,73mg mL-1). Samples of skin and seeds had lower EC50 values than various fruits and seeds known for their antioxidant activity. Only the CM70% showed levels of cytotoxicity in the three highest concentrations, the other samples showed no cytotoxicity at higher concentrations and increased cell viability. Thus we conclude that the mandacaru fruit has compounds with potent antioxidant capacity and could be used by the industry for fresh consumption in the form of juice, pulp, or extraction of antioxidant compounds that can later be used as additives in food. / As cactáceas são plantas bastante resistentes a períodos de seca, entre elas está incluído o Cereus jamacaru, conhecido como mandacaru, que é um cacto colunar comum no Brasil, produz um fruto comestível, vermelho, carnoso, com polpa branca e sementes pequenas. Os frutos além de fornecerem nutrientes essenciais, também produzem princípios ativos com propriedades biológicas, como a atividade antioxidante. Desta forma o principal objetivo do trabalho foi avaliar o potencial antioxidante, a citotoxicidade e verificar a composição química das partes do fruto de Cereus jamacaru DC, visando incentivar o consumo e o aproveitamento industrial do fruto. Foram separadas as partes dos frutos (casca, polpa e semente), e feitas extrações com etanol 70% e 95% de cada parte, resultando em seis amostras: casca (CM70%, CM95%), polpa (PM70%, PM95%) e semente (SM70%, SM95%). A atividade antioxidante foi avaliada através do método de seqüestro de radicais livres DPPH (2,2-difenil-1-picrilhidrazila). foram testadas as seis amostras nas concentrações de 100 a 2000μg.mL-1. Os controles positivos foram o eugenol e o β-caroteno. A partir dos resultados foi calculada a porcentagem da atividade antioxidante (AA%) e a Concentração Eficiente (EC50). O perfil cinético foi determinado pela redução do DPPH em função do tempo. A caracterização química das amostras foi realizada por espectroscopia no infravermelho. A citotoxicidade foi determinada pelo método MTT sobre macrófagos. Com os dados obtidos através do infravermelho, verificou-se que as seis amostras apresentam diferentes compostos potencialmente antioxidantes. As amostras da casca apresentaram AA% superiores ao β- caroteno em todas as concentrações testadas. A CM70% foi mais eficiente que a CM95%, com AA% aproximada ao eugenol nas concentrações de 1000 e 2000 μg/ml. A amostra PM95% demonstrou maior porcentagem antioxidante que a PM70%, sendo comparável ao β- caroteno nas concentrações de 100-300μg/ml e mediana nas concentrações superiores. Já a SM70% e a SM95% exibiram as mais altas AA% entre as amostras, sendo similares ou superiores ao eugenol a partir da concentração de 400μg/ml. As amostras exibiram três perfis de cinética: Rápida para as amostras SM70%, SM95% e CM70%, Intermediária para a CM95% e lenta para a PM70% e PM95%. Os menores valores de EC50 foram observados nas amostras de semente e casca: SM70% (0,233mg/mL), SM95% (0,217mg/mL); CM70% (0,56mg/mL), CM95% (0,94 mg/mL). Sendo que os valores de EC50 mais elevados foram observados nas amostras de polpa: PM70% (10,95 mg/mL) e PM95% (8,73mg/mL). As amostras de casca e semente destacaram-se, apresentando valores de EC50 menores do que várias frutas e sementes já conhecidas por sua ação antioxidante. Apenas a amostra CM70% mostrou níveis de citotoxicidade nas três maiores concentrações, as demais amostras não apresentaram citotoxicidade, e nas concentrações mais elevadas aumentaram a viabilidade celular. Desta forma é possível concluir que o fruto possui compostos com capacidade antioxidante potente, podendo vir a ser utilizado pela indústria, para o consumo in natura, na forma de suco, polpa, ou para extração de compostos antioxidantes podendo ser posteriormente utilizados como aditivos em alimentos.

BRITO, V.S. Avaliação da toxidade e do potencial fotoprotetor e antioxidante do extrato hidroalcoólico bruto de hastes de Cereus jamacaru DC, cactaceae. 2013. 69 f. Dissertação (MESTRADO EM BIOTECNOLOGIA) - Campus de Sobral, Universidade Federal do Ceará, Sobral, 2013. / Submitted by Djeanne Costa (djeannecosta@gmail.com) on 2017-09-04T10:58:53Z No. of bitstreams: 1 2013_dis_vsdbrito.pdf: 2187602 bytes, checksum: 5226f56dd719e4c145af3dd52d3138aa (MD5) / Approved for entry into archive by Djeanne Costa (djeannecosta@gmail.com) on 2017-10-03T15:07:31Z (GMT) No. of bitstreams: 1 2013_dis_vsdbrito.pdf: 2187602 bytes, checksum: 5226f56dd719e4c145af3dd52d3138aa (MD5) / Made available in DSpace on 2017-10-03T15:07:31Z (GMT). No. of bitstreams: 1 2013_dis_vsdbrito.pdf: 2187602 bytes, checksum: 5226f56dd719e4c145af3dd52d3138aa (MD5) Previous issue date: 2013 / Cactaceae is family of plants abundant in semi-arid regions. They present a number of morphological and physiological adaptations that allow their survival in environments with a deficit in nutrients and water, and supports intense solar radiation. The aim of this study was to evaluate the chemical composition (by spectroscopy Fourier transform infrared), toxicity (essays with Artemia salina) and potential photoprotective and antioxidant of ethanol extract (95 and 70%) of Cereus jamacaru stems collected in the periods of day and night. The results of the study of the chemical composition showed variation in the composition according to the sampling period and the process of extracting ethanol (95 or 70%). The 95% ethanol extract of stems collected during the day (ECD 95%) showed no toxicity while others showed toxicity. All the extracts showed photoprotective and antioxidant (as compared to beta carotene) activity. However, the highest activities were observed in the ECD 95%. These results demonstrate the potential photoprotective and antioxidant of ethanol extracts of Cereus jamacaru stems in the production of biotechnological products. / As cactáceas são compostas por um grupo de plantas abundantes nas regiões do semiárido. Demonstram bastante especificidade com relação ao seu habitat e possuem uma série de adaptações morfológicas e fisiológicas que permitem a sua sobrevivência em ambientes com déficit em nutrientes e água, além de suportar intensa radiação solar (FPS). Dessa forma o objetivo deste trabalho foi avaliar o efeito do Fator de Proteção Solar possivelmente presente em hastes de Cereus jamacaru, verificar a sua porcentagem de atividade antioxidante, testar a toxicidade através do teste preliminar com Artemia salina e verificar a composição química do extrato através do infravermelho. Primeiramente foi preparado o material vegetal de Cereus jamacaru resultando em extrato bruto, derivado de coletas durante o dia (11h) e coletas durante a noite (23h). Após isso foi realizado extrações com etanol a 70% e 95% v/v para ambos os horários de coleta. Resultando em: ECD 95%, ECD 70%, ECN 95% e ECN 70%. Os espectros no infravermelho foram verificados tanto para o extrato bruto, quanto para as frações liofilizadas, as bandas de absorção foram obtidas em comprimento de onda na faixa de 4000 a 400 cm-1. Para o teste de FPS in vitro, as amostras foram diluídas até a concentração final de 0,2 mg/mL, e as absorbâncias determinadas na faixa de 220 a 450 nm, com intervalos de 2 nm. A atividade antioxidante foi avaliada através do método de sequestro de radicais livres DPPH (2,2-difenil-1-picrilhidrazila), sendo realizados testes para as quatro amostras nas concentrações de 5 a 2000μg.mL-1 em triplicata. As leituras das absorbâncias foram realizadas a 517 nm. A partir do resultado foi calculado a porcentagem de atividade antioxidante (AA%). Todas as amostras foram submetidas ao teste de toxicidade com Artemia salina, nas seguintes concentrações de (1000, 500, 250, 125 e 62,5μg.mL-1). Logo após verificada a mortalidade dos náuplios com 24 e 48h. Com relação ao infravermelho foram verificados picos de absorção diferentes quando comparados tanto o horário de coleta quanto a porcentagem de diluição do solvente. Para o teste de FPS todas as amostras demonstraram atividade fotoprotetora sendo que na amostra (ECD 95%) foi verificado uma maior absorção na região do ultravioleta (UV) com FPS-15,72. As amostras demonstraram uma maior atividade antioxidante comparado ao β-caroteno, na maioria das concentrações testadas. Os testes de toxicidade com Artemia salina resultaram em valores para a concentração letal média (CL50), >1000; 906,32; 622,30; 762,44 μg mL-1 para os extratos (ECD 95%, ECD 70%, ECN 95% e ECN 70%) respectivamente, após 24h. A amostra ECD 95% mostrou ser atóxica até a concentração testada. As demais amostras demonstraram toxicidade de acordo com o que é relatado na literatura, em que concentrações de CL50 abaixo de 1000 é considerado tóxica. Considerando que, para os experimentos em estudo foi verificado tanto efeito fotoprotetor quanto atividade antioxidante em concentrações bem abaixo dos valores de CL50, assim podemos considerar o extrato como atóxico, embora sejam necessários outros testes de toxicidade, in vitro e in vivo buscando descartar o efeito tóxico que possa vir a ter, viabilizando a utilização de seus princípios ativos em fármacos ou produtos cosméticos.

This thesis aims to hardware and software integration of solid oxide fuel cell into a power generator for truck application. Requirements for individual components are defined, especially for main DC/DC converter which allows charging the battery pack with output from fuel cell. Then suitable components are found on the market and incorporated into hardware layout. Operation strategy with safety concept is proposed and consequently integrated into PLC in LASAL Class 2 environment. This is followed by definition of future work which includes testing and possible changes in components. Result is hardware and software design which allows construction of prove-of-concept prototype.