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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.
1

Metodologia de análise do potencial solar e eólico na zona urbana apoiado em geoprocessamento - Caso USP Campus Butantã. / Methodology of analysis of solar and wind potential in the urban area supportes by geoprocessing: USP Butantã case.

Cruz, Francy Mayerly Sanchez 22 February 2017 (has links)
A geração de energia a partir de fontes renováveis tem apresentado um maior grau de relevância nos governos mundiais devido à crescente preocupação pelo meio ambiente e em especial pelos efeitos nocivos1 que a utilização de combustíveis fósseis produz. No panorama brasileiro essa preocupação está presente, e uma das ações implementadas corresponde ao estabelecimento de políticas que favorecem à geração de energia limpa como o Programa de Incentivo às Fontes Alternativas (PROINFA). Por essa razão, é muito importante estabelecer e analisar o potencial de geração mediante fontes renováveis como solar e eólica que são as fontes que tem aumentado sua inserção na matriz energética brasileira nos últimos anos, além de ter demonstrado sua viabilidade econômica e técnica na maioria dos projetos. Essa análise inicial de levantamento de potencial deve estar apoiada em tecnologias como as ferramentas de geoprocessamento, que permitem otimizar variáveis como os recursos, o tempo, entre outras, para ter uma primeira aproximação e avaliação da escolha de fonte energética que seja mais adequada no local ou seleção de locais ótimos para a geração por determinado tipo de fonte, além de outras aplicações em diversos estudos no setor energético. Este projeto de pesquisa pretendeu propor uma metodologia para realizar uma pré-avaliação do potencial de geração por fontes renováveis, levando em conta uma análise conjunta de critérios com relação à infraestrutura existente, o cálculo do recurso energético, e um componente ambiental apoiado no geoprocessamento. Foi aplicado num estudo de Caso no Campus Butantã da Universidade de São Paulo, para o potencial de geração de energia solar e eólica. / The generation of energy from renewable sources has shown a greater degree of relevance in the world governments due to the growing concern for the environment and especially the harmful effects that the use of fossil fuels produces. In the Brazilian scenario this concern is present, and one of the implemented actions corresponds to the establishment of policies that favor the generation of clean energy such as the Alternative Sources Incentive Program (PROINFA). For this reason, it is very important to establish and analyze the generation potential using renewable sources such as solar and wind, which are the sources that have increased their insertion in the Brazilian energy matrix in recent years, besides having demonstrated their economic and technical feasibility in most Projects. This initial analysis of potential survey should be supported by technologies such as geoprocessing tools, which allow optimizing variables such as resources, time, among others, to have a first approximation and evaluation of the choice of energy source that is more appropriate in the place Or selection of optimal locations for generation by a particular type of source, as well as other applications in several studies in the energy sector. This research project intends to propose a methodology to carry out a pre-evaluation of the potential of generation by renewable sources, taking into account a joint analysis of criteria regarding the existing infrastructure, the calculation of the energy resource, and an environmental component supported in geoprocessing. It was applied in a case study at the Butantã Campus of the University of São Paulo, for the potential of solar and wind power generation.
2

Metodologia de análise do potencial solar e eólico na zona urbana apoiado em geoprocessamento - Caso USP Campus Butantã. / Methodology of analysis of solar and wind potential in the urban area supportes by geoprocessing: USP Butantã case.

Francy Mayerly Sanchez Cruz 22 February 2017 (has links)
A geração de energia a partir de fontes renováveis tem apresentado um maior grau de relevância nos governos mundiais devido à crescente preocupação pelo meio ambiente e em especial pelos efeitos nocivos1 que a utilização de combustíveis fósseis produz. No panorama brasileiro essa preocupação está presente, e uma das ações implementadas corresponde ao estabelecimento de políticas que favorecem à geração de energia limpa como o Programa de Incentivo às Fontes Alternativas (PROINFA). Por essa razão, é muito importante estabelecer e analisar o potencial de geração mediante fontes renováveis como solar e eólica que são as fontes que tem aumentado sua inserção na matriz energética brasileira nos últimos anos, além de ter demonstrado sua viabilidade econômica e técnica na maioria dos projetos. Essa análise inicial de levantamento de potencial deve estar apoiada em tecnologias como as ferramentas de geoprocessamento, que permitem otimizar variáveis como os recursos, o tempo, entre outras, para ter uma primeira aproximação e avaliação da escolha de fonte energética que seja mais adequada no local ou seleção de locais ótimos para a geração por determinado tipo de fonte, além de outras aplicações em diversos estudos no setor energético. Este projeto de pesquisa pretendeu propor uma metodologia para realizar uma pré-avaliação do potencial de geração por fontes renováveis, levando em conta uma análise conjunta de critérios com relação à infraestrutura existente, o cálculo do recurso energético, e um componente ambiental apoiado no geoprocessamento. Foi aplicado num estudo de Caso no Campus Butantã da Universidade de São Paulo, para o potencial de geração de energia solar e eólica. / The generation of energy from renewable sources has shown a greater degree of relevance in the world governments due to the growing concern for the environment and especially the harmful effects that the use of fossil fuels produces. In the Brazilian scenario this concern is present, and one of the implemented actions corresponds to the establishment of policies that favor the generation of clean energy such as the Alternative Sources Incentive Program (PROINFA). For this reason, it is very important to establish and analyze the generation potential using renewable sources such as solar and wind, which are the sources that have increased their insertion in the Brazilian energy matrix in recent years, besides having demonstrated their economic and technical feasibility in most Projects. This initial analysis of potential survey should be supported by technologies such as geoprocessing tools, which allow optimizing variables such as resources, time, among others, to have a first approximation and evaluation of the choice of energy source that is more appropriate in the place Or selection of optimal locations for generation by a particular type of source, as well as other applications in several studies in the energy sector. This research project intends to propose a methodology to carry out a pre-evaluation of the potential of generation by renewable sources, taking into account a joint analysis of criteria regarding the existing infrastructure, the calculation of the energy resource, and an environmental component supported in geoprocessing. It was applied in a case study at the Butantã Campus of the University of São Paulo, for the potential of solar and wind power generation.
3

Μοντελοποίηση και μελέτη ανανεώσιμων πηγών ενέργειας με χρήση υπολογιστικών συστημάτων

Κυρούλη, Βασιλική, Παπαχρήστου, Ιωάννα 28 August 2009 (has links)
Οι σύγχρονες κοινωνίες καταναλώνουν τεράστιες ποσότητες ενέργειας για τη θέρμανση χώρων, τα μέσα μεταφοράς, την παραγωγή ηλεκτρικής ενέργειας, καθώς και για τη λειτουργία των βιομηχανικών μονάδων. Το μεγαλύτερο ποσοστό ενέργειας που χρησιμοποιείται προέρχεται από συμβατικές πηγές ενέργειας, όπως είναι το πετρέλαιο, η βενζίνη και ο άνθρακας, που αργά ή γρήγορα θα εξαντληθούν. Από την άλλη πλευρά, οι Ανανεώσιμες Πηγές Ενέργειας ανανεώνονται μέσω του κύκλου της φύσης και θεωρούνται πρακτικά ανεξάντλητες. Γενικά θεωρούνται οι εναλλακτικές των παραδοσιακών πηγών ενέργειας. Οι κυριότερες μορφές των ΑΠΕ είναι η υδροηλεκτρική ενέργεια, η θαλάσσια ενέργεια, η ενέργεια που προέρχεται από τη βιομάζα, η γεωθερμική ενέργεια, το υδρογόνο, η ηλιακή ενέργεια και η αιολική. Έχουν πολλά πλεονεκτήματα έναντι άλλων πηγών ενέργειας, όπως το γεγονός ότι είναι πρακτικά ανεξάντλητες, δε μολύνουν το περιβάλλον και έχουν χαμηλό λειτουργικό κόστος. Είναι εγχώριες πηγές ενέργειας και συνεισφέρουν στην ενίσχυση της ενεργειακής ανεξαρτησίας. Δημιουργούν σημαντικό αριθμό νέων θέσεων εργασίας. Αποτελούν πυρήνα για την αναζωογόνηση οικονομικά και κοινωνικά υποβαθμισμένων περιοχών και πόλο για τη τοπική ανάπτυξη, με την προώθηση ανάλογων επενδύσεων. Η αύξηση των επενδύσεων σε ΑΠΕ άρχισε να γίνεται ιδιαίτερα αισθητή την τελευταία δεκαετία όπου παρατηρείται έντονη άνοδος στην επενδυτική δραστηριότητα και συνεπώς στην εγκατεστημένη ισχύ μονάδων παραγωγής ενέργειας. Πέρα από τα μεγάλα υδροηλεκτρικά, που υπερέχουν σημαντικά ως προς την εγκατεστημένη ισχύ, το ενδιαφέρον επικεντρώνεται κυρίως στα αιολικά και στα φωτοβολταϊκά. Όμως, παρά την ανοδική τους τάση οι ΑΠΕ παραμένουν ανεπαρκώς ανεπτυγμένες, κυρίως αν ληφθούν υπόψη οι ευνοϊκές κλιματολογικές συνθήκες στη χώρα μας (πλούσιο αιολικό δυναμικό και υψηλό επίπεδο ηλιοφάνειας). Η ανάπτυξη των ΑΠΕ στη χώρα μας προωθείται από τους στόχους που έχουν τεθεί από την Ευρωπαϊκή Ένωση, την αυξανόμενη ζήτηση ηλεκτρικής ενέργειας, από την πτώση του κόστους παραγωγής των ΑΠΕ και την ταυτόχρονη άνοδο του κόστος παραγωγής των συμβατικών καυσίμων καθώς και από το ευνοϊκό θεσμικό πλαίσιο που αφορά τις γενναιόδωρες επιδοτήσεις κεφαλαίου για την πραγματοποίηση επενδύσεων σε ΑΠΕ και την τιμολόγηση του παραγόμενου από ΑΠΕ ηλεκτρικού ρεύματος για την επόμενη εικοσαετία. Δυστυχώς η δυσχερής και χρονοβόρα διαδικασία αδειοδότησης, η έλλειψη χωροταξικού σχεδιασμού για τις ΑΠΕ, που επιτρέπει σε κάθε πολίτη να εμποδίσει την εγκατάσταση μονάδων με χρήση ΑΠΕ, καθώς και το γεγονός ότι η κατασκευή, λειτουργία και συντήρηση των μονάδων ηλεκτροπαραγωγής εξαρτάται από τους προμηθευτές και τη διαθεσιμότητα εξοπλισμού και πρώτων υλών εμποδίζουν πρακτικά την ανάπτυξη των ΑΠΕ στη χώρα μας. Το υπό διερεύνηση σύστημα που μελετάται είναι η σύνδεση ανεμογεννήτριας σε ισχυρό δίκτυο. Η ανεμογεννήτρια αποτελείται από τον ανεμοκινητήρα και τη σύγχρονη γεννήτρια. Επειδή η ένταση του ανέμου είναι μεταβλητή, για τη σωστή λειτουργία της σύγχρονης γεννήτριας χρησιμοποιούνται συστήματα ελέγχου προκειμένου να διατηρηθούν η τάση και η συχνότητα στις ονομαστικές τους τιμές. Στη συγκεκριμένη εργασία, γίνεται η προσομοίωση του υπό διερεύνηση συστήματος στο ATP-EMTP και παρατίθενται σχηματικά διαγράμματα για διάφορες τιμές της ταχύτητας του ανέμου συναρτήσει της ακτίνας του πτερυγίου και της αδράνειας του συστήματος. Η ταχύτητα του ανέμου κατέχει βασικό ρόλο στη συμπεριφορά της λειτουργίας μιας ανεμογεννήτριας. Καθώς αυξάνεται η ταχύτητα του ανέμου, αυξάνονται η γωνιακή ταχύτητα του ανεμοκινητήρα και η μηχανική ροπή στην είσοδο της σύγχρονης γεννήτριας, συνεπώς και η ροπή του ανεμοκινητήρα. Το χρονικό σημείο όπου το σύστημα εισέρχεται στη μόνιμη κατάσταση λειτουργίας είναι ίδιο, γεγονός που οφείλεται στη μη μεταβολή της αδράνειας του συστήματος. Επίσης παρατηρείται, ότι η αύξηση της ταχύτητας του ανέμου έχει σαν αποτέλεσμα η ισχύς του συστήματος να αυξάνεται όπως και είναι αναμενόμενο, αλλά από μια ταχύτητα του ανέμου και πάνω η παραγόμενη ισχύς δεν παρουσιάζει την ίδια συμπεριφορά γεγονός που οφείλεται στα λειτουργικά χαρακτηριστικά του ανεμοκινητήρα και στις χαρακτηριστικές που εκφράζουν τη λειτουργία του (cp (λ)). Συνεχίζοντας την ανάλυση του συστήματος του ανεμοκινητήρα παρατηρείται ότι καθώς η αδράνεια του συστήματος παραμένει σταθερή η γωνιακή ταχύτητα του ανεμοκινητήρα σταθεροποιείται χρονικά στο ίδιο σημείο για διαφορετικές τιμές της ταχύτητας του ανέμου, όπως και αναμένονταν. Κατά το αρχικό χρονικό διάστημα η γωνιακή ταχύτητα του ανεμοκινητήρα παρουσιάζεται ιδιαίτερα μεταβαλλόμενη, γεγονός που οφείλεται στον προσδιορισμό των αρχικών συνθηκών του συστήματος. Οι αρχικές συνθήκες των μεταβλητών του συστήματος θεωρούνται σταθερές για οποιαδήποτε τιμή της ταχύτητας του ανέμου (παραδοχή). Καθώς η αδράνεια μεγαλώνει υφίσταται μείωση των μεταβολών της γωνιακής ταχύτητας και η γωνιακή ταχύτητα ισορροπεί σε διαφορετικούς χρόνους για διάφορες τιμές της αδράνειας. Ένα άλλο βασικό μέγεθος που επηρεάζει τη λειτουργία μιας ανεμογεννήτριας είναι η ακτίνα των πτερυγίων της. Αυξάνοντας την ακτίνα των πτερυγίων, αυξάνεται η γωνιακή ταχύτητα του ανεμοκινητήρα καθώς και η ροπή εισόδου στη σύγχρονη γεννήτρια, και συνεπώς η παραγόμενη μηχανική ισχύς στην έξοδο του ανεμοκινητήρα. Έγινε και επιβεβαίωση των αποτελεσμάτων, αφού τόσο η μεταβολή της ακτίνας των πτερυγίων όσο και η μεταβολή της ταχύτητας του ανέμου οδήγησαν σε αντίστοιχα αποτελέσματα που ανταποκρίνονταν στις αναλυτικές εξισώσεις που εκφράζουν τον ανεμοκινητήρα και που παρουσιάστηκαν στη διπλωματική εργασία. Κατόπιν στο σύστημα προστίθεται σύγχρονη γεννήτρια συνδεδεμένη με τριφασικό ωμικό φορτίο. Προτιμήθηκε σύγχρονη γεννήτρια καθώς έχει τη δυνατότητα παραγωγής άεργου ισχύος σε αντίθεση με την ασύγχρονη, και για αυτό το λόγο πλέον χρησιμοποιούνται περισσότερο συγκριτικά με τα προηγούμενα έτη. Τελειώνοντας, συνδέεται η ανεμογεννήτρια σε ισχυρό δίκτυο, και παρουσιάζονται αποτελέσματα που αφορούν τα ρεύματα στο εσωτερικό της μηχανής αλά και στην έξοδό της, καθώς και οι τάσεις του συστήματος και η γωνιακή ταχύτητα. Επίσης γίνεται διερεύνηση της λειτουργικής συμπεριφοράς του συστήματος σε περιπτώσεις σφαλμάτων συμμετρικών και μη. Επισημαίνεται ότι το ρεύμα διέγερσης Ιf δεν αλλάζει τιμή καθώς το σύστημα δεν διαθέτει έλεγχο. Παρ’ όλ’ αυτά έγινε προσπάθεια προσομοίωσης της σύγχρονης γεννήτριας που επιλέχθει με τα συστήματα ελέγχου P-f, Q-V και για τα οποία παρουσιάστηκαν τα αντίστοιχα σχηματικά διαγράμματα. / The Renewable Sources of Energy are considered generally as the alternatives to the traditional sources of energy. They are thus named because most of them are renewed in the nature. They are immediately used (mainly for heating) or changed into other forms of energy (electric or mechanic energy). It is calculated that the bigger part of electric energy that is produced worldwide, is produced by stations that use RSE. They have a lot of advantages against other sources of energy, as the fact that they are practically inexhaustible; they do not pollute the environment and have low functional cost. As main forms of RSE are reported the hydroelectric energy, the marine energy, the energy that emanate from the biomass, the geothermal energy, the hydrogen, the solar energy and aeolian. The growth of RSE in our country is promoted by the objectives that have been placed by the European Union, the increasing demand of electric energy, from the fall of cost of production of RSE and the simultaneous rise in the cost of conventional fuels production, as well as from the favorable institutional frame that concerns the generous capital subsidies for the realization of investments in RSE and the pricing produced from RSE of electric current for the next 20 years. Unfortunately, the awkward and time-consuming process of vacations awarding, the lack of land-planning for the RSE, that allows in each citizen to prevent the installation of units with use of RSE, as well as the fact that the manufacture, operation and maintenance of units for electricity generation depends on the suppliers and the availability of equipment and raw material, prevents practically the growth of RSE in our country. The system under investigation is the connection of wind generator in powerful network. The wind generator is constituted by a wind-motor and a synchronous generator. The wind turns the fins of wind generator, which are connected with a turned axis. The axis passes in a box of movement transmission, where the speed of rotation is increased. The box is connected with axis of big speed of rotation, which moves an electricity production generator. If the intensity of wind is strengthened too much, the turbine has a brake that limits the excessive increase of rotation of the fins in order to limit its deterioration and to avoid destruction. For the right operation of synchronous generator are used control systems so that tendency and frequency are maintained in their nominal prices. In conclusion, a simulation of the system is presented in the ATP-EMTP and schematic diagrams are mentioned on various prices of wind speed in connection with the beam of fins of wind generator and the system’s inactivity.
4

Espectroscopia UV-Vis para avaliação de biodiesel e misturas biodiesel/diesel

Fernandes, David Douglas de Sousa 18 February 2013 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-12-05T11:47:50Z No. of bitstreams: 1 PDF - David Douglas de Sousa Fernandes.pdf: 2350130 bytes, checksum: 479e48d76037cc92ae400749c168cb38 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2016-12-06T19:16:54Z (GMT) No. of bitstreams: 1 PDF - David Douglas de Sousa Fernandes.pdf: 2350130 bytes, checksum: 479e48d76037cc92ae400749c168cb38 (MD5) / Made available in DSpace on 2016-12-06T19:16:54Z (GMT). No. of bitstreams: 1 PDF - David Douglas de Sousa Fernandes.pdf: 2350130 bytes, checksum: 479e48d76037cc92ae400749c168cb38 (MD5) Previous issue date: 2013-02-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Biodiesel is a fuel derived from renewable sources and can be obtained from vegetable oils, animal fat until residual oils. In Brazil commercialization of biodiesel occurs in blends, being added 5 % to diesel (B5). Biodiesel to be marketed must follow a series of standards established by Brazilian National Agency of Petroleum, Natural Gas and Biofuels (ANP). However alternative methodologies are being developed for the purpose and quality control of biodiesel. The objective of this work is to build multivariate models, in first moment to classify samples of biodiesel produced from different oils, in the second moment to predict the amount of biodiesel blended with diesel, and finally to classify mixtures biodiesel/diesel adulterated with soybean oil. In all cases molecular UV-Vis spectroscopy was used. An exploratory analysis was used to determine the behavior of the samples under study, for this we used the Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). To classify samples biodiesel and blends biodiesel/diesel recognition techniques were used such as Supervised Independent Modeling of Soft Analogies between Classes (SIMCA) and Linear Discriminate Analysis technique associated with variable selection Successive Projections Algorithm (SPA-LDA). To predict the amount of biodiesel blended with diesel was used variable selection Successive Projections Algorithm (SPA) and Stepwise (SW), techniques associated with Multiple Linear Regression (MLR) and compared the values with Partial Least Squares (PLS). Based on the results obtained, it is possible to carry out the classification of samples of biodiesel from the oil source and the samples contaminated with soybean oil with 100% success. For predicting biodiesel content in blends biodiesel/diesel results were further adjusted using the SPA-MLR, where the average error of prediction was 0.57 %. / O biodiesel é um combustível proveniente de fontes renováveis e pode ser obtido desde óleos vegetais, gordura animal até óleos residuais. No Brasil a comercialização do biodiesel ocorre em forma de misturas, sendo adicionados 5% ao diesel (B5). Para ser comercializado o biodiesel deve obedecer a uma série de parâmetros estabelecidos em normas utilizadas pela Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP). Contudo metodologias alternativas estão sendo desenvolvidas com o propósito no controle e na qualidade do biodiesel. Objetivou-se com este trabalho a construção de modelos multivariados capazes em primeiro momento de classificar amostras de biodiesel produzidas a partir dos óleos de origens distintas, em segundo momento de predizer o teor de biodiesel misturado ao diesel, e por fim classificar misturas biodiesel/diesel adulteradas com óleo de soja. Em todos os casos utilizou-se a espectroscopia de absorção molecular UV-Vis. Análise exploratória foi utilizada pra determinar o comportamento das amostras em estudo, para tal utilizou-se a Análise por Componentes Principais (PCA) e a Análise de Agrupamentos Hierárquicos (HCA). Para classificar as amostras de biodiesel e de misturas biodiesel/diesel foram utilizadas técnicas de reconhecimento supervisionadas tais como a Modelagem Suave Independente de Analogias entre Classes (SIMCA) e Análise Discriminante Linear associada a técnica de seleção de variáveis Algoritmo das Projeções Sucessivas (SPA- LDA). Para predizer a quantidade de biodiesel misturado ao diesel foi empregada seleção de variáveis Algoritmo das Projeções Sucessivas (SPA) e Stepwise (SW) associados a técnica de Regressão Linear Múltipla (MLR) e comparados os valores obtidos a técnica dos Mínimos Quadrados Parciais (PLS). Com base nos resultados obtidos é possível realizar a classificação das amostras de biodiesel a partir do óleo de origem e das amostras contaminadas com óleo de soja com 100% de êxito. Na predição do teor de biodiesel em misturas biodiesel/diesel os resultados foram mais ajustados utilizando o SPA-MLR, onde o erro médio de predição foi de 0,57 %.
5

Občanská stavba / Civil building

Krestýn, Miroslav Unknown Date (has links)
The diploma thesis titled "Civil building" consists of three main parts. The theoretical, project and calculation sections are created. The common theme of these parts is the assessment of the energy performance of the proposed building. The object is designed as a two-storey office building that meets the current requirements for new construction under the energy certificate. The goal of the work is the design of the optimisation of the building in the form of individual options for energy certificates and their mutual comparison.
6

Energetické právo a ochrana životního prostředí / Energy law and protection of the environment

Vohnoutová, Alena January 2011 (has links)
The aim of my thesis is to create a comprehensive overview of energy law with special focus on its influence on the environment. It especially deals with individual renewable energy sources and their support, construction of facilities utilizing these sources and their impact on the environment. Last but not least, in each chapter I draw attention to recent or expected amendments to relevant legislation. In the first chapter I divide sources of energy into the fossil, nuclear and renewable ones. Besides presenting the basic characteristics of such sources, I also deal with the time period in which the humankind will run out of their supplies, as well as with detrimental effects that their mining and processing have on the environment. Based on the classification included in the Act on the Promotion of Renewable Energy Sources, I continue with classifying the renewable energy sources to wind power, energy of water and solar radiation, geothermal energy, biomass and biogas. I consider their benefits, but also their harmful effects on the environment. Each subchapter also contains a part that deals with the potential of such resources in the Czech Republic. Since Czech energy law is influenced by both international and European laws, I dedicate the next chapter to them. On the level of international...
7

ENERGETICKÁ POLITIKA SRN: VÝCHODISKÁ A ANALÝZA DOPADOV V KONTEXTE POLITIKY EU / Energy policy for Germany: the impact of European energy policy strategy

Šátek, Lukáš January 2011 (has links)
The aim of my thesis is to analyze the energy policy in Germany and its future development. There are many external and internal factors influencing the way how the energy policy is going to evolve. One of these factors is the common European energy policy. In order to cover its energy demand, EU is forced to establish a comprehensive energy policy on the European level. The increasing pressure caused by the combination of external and internal factors calls for better cooperation on this field. The key element of the future energy policy in EU will be the renewable sources of energy.
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synthesis and characterization of a meso-porphyrin derivate the lcc, how to disable metals: zinc, copper and nickel. / SÃntese e caracterizaÃÃo de uma meso-porfirina, derivada do lcc, como desativadora dos metais: zinco, cobre e nÃquel

Tassio Lessa do Nascimento 18 June 2010 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A busca por processos quÃmicos que reduzam ou eliminem o uso e a geraÃÃo de substÃncias tÃxicas tem sido crescente nas Ãltimas dÃcadas. Com este novo direcionamento para reduÃÃo do impacto das atividades industriais, foram propostas alternativas que possam reduzir o impacto ambiental. Neste aspecto, foram sintetizados meso-porfirnas do tipo A4 (meso-5,10,15,20) a partir do LÃquido da Casca da Castanha do Caju - LCC (uma fonte renovÃvel, local, abundante e biodegradÃvel). O primeiro derivado refere-se à formaÃÃo do composto bromado, seguido da obtenÃÃo do derivado aldeÃdico, finalmente, com o auxÃlio do pirrol, tem-se a formaÃÃo da meso-porfirina. Os compostos foram purificados em coluna cromatogrÃfica e caracterizados por tÃcnicas experimentais de RMN 13C e 1H , GC-EM, IV e UV-VIS, que confirmaram a obtenÃÃo do produto desejado. A porfirina base livre foi submetida aos processos de metalaÃÃo utilizando-se para isto, Ni(C2H3O2).4H2O, Zn(CH3COO)2 e Cu(CH3COO)2, como sal doador do metal e diclorometano como solvente, a reaÃÃo permaneceu em agitaÃÃo constante. A metalaÃÃo foi acompanhada por espectroscopia no UV-VIS e cromatografia de camada delgada. / The search for chemical processes that reduce or el iminate the use and generation of toxic substances has been increasing in recent deca des. With this new direction for reducing the impact of industrial activities have p roposed alternatives that could reduce the environmental impact. Here, were synthesized po rphyrins of A4 type (5, 10,15,20) from the bark of the Net's Cashew nuts - LCC (a ren ewable source, location, abundant and biodegradable). The first derivative is the for mation of the compound bromine, followed by obtaining a secondary aldehydic, finall y, with the help of pyrrole, has been the formation of porphyrin. The compounds were puri fied by column chromatography and characterized by experimental techniques of 1 H and 13 C NMR, GC-EM, IR and UV- VIS, which confirmed the achievement of the desired product. The porphyrin free base was subjected to the processes of metallic using it for this, Ni(C 2 H 3 O 2 ).4H 2 O, Cd(CH 3 COO) 2 and Pb(CH 3 COO) 2 , as the metal salt donor and dichloromethane as solvent as the reaction methodology remained in con stant turmoil. The metallic processes were accompanied by the UV-VIS spectrosco py and thin-layer chromatography.
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Aplicação de pigmento preto de carvão vegetal em polietileno de baixa densidade e influência da radiação ionizante / Application of Pigment blck charcoal in low density polyethylene and influence of the ionizing radiation

SANTOS, MAURICIO C.F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:37Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
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Aplicação de pigmento preto de carvão vegetal em polietileno de baixa densidade e influência da radiação ionizante / Application of Pigment blck charcoal in low density polyethylene and influence of the ionizing radiation

SANTOS, MAURICIO C.F. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:25Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:37Z (GMT). No. of bitstreams: 0 / Neste trabalho foi estudado o desenvolvimento de um pigmento vegetal preto que possui características semelhantes aos já existentes no mercado de transformação de termoplásticos. Atualmente o pigmento preto mais utilizado nas indústrias de transformação de termoplásticos é o negro de fumo, cujo processo de obtenção gera muitos resíduos tóxicos e quando liberados na atmosfera aumenta a poluição do ar. O pigmento em estudo possui a estrutura química formada por 97% de carbono proveniente da moagem e micronização do carvão vegetal. Os objetivos do presente trabalho foram estudar a obtenção do pigmento preto de origem do carvão vegetal, estudar o desempenho deste pigmento comparando-o com o negro de fumo usado atualmente nas indústrias, incorporação do pigmento obtido em polietileno de baixa densidade (PEBD), caracterização do produto obtido e estudo da influência da radiação ionizante no PEBD mais pigmento preto. Como matérias prima foram utilizadas o carvão vegetal (pigmento preto) e o polietileno de baixa densidade (PEBD). Posteriormente, o pigmento preto obtido foi incorporado ao PEBD pelo processo de injeção e caracterizado em relação a sua estabilidade durante processamento, dispersão, migração e cobertura pigmentar. Também foram realizados testes mecânicos com as amostras não irradiadas e as irradiadas em doses de radiação de 100, 200, 300 e 400kGy. O pigmento foi obtido por meio da moagem do carvão vegetal, sua obtenção é menos nociva ao meio ambiente, visto que o mesmo não é um subproduto do petróleo como o negro de fumo e sim um derivado da madeira que é um produto renovável. É importante salientar que é possível canalizar o descarte de maneira inadequada da madeira para uma linha produtiva, produzindo assim o carvão o qual é matéria prima para este pigmento e assim ser inserido em cadeia produtiva. Apesar da aplicação em matriz polimérica ter sido maior que a do negro de fumo 1,4%, o mesmo é de fácil obtenção, proveniente de uma fonte renovável, sendo de baixo custo além de apresentar propriedades colorimétricas compatíveis e próximas às do negro de fumo. Em relação à incorporação do pigmento na matriz polimérica durante o processo de injeção, o mesmo foi de fácil incorporação distribuindo-se de maneira homogênea. Em relação às amostras irradiadas pode-se dizer que houve ganhos na maioria das propriedades estudadas. Dependendo do tipo de artefato a ser fabricado e de quais propriedades são mais importantes, pode-se irradiá-lo em dose mais adequada. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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