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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.
101

Estudo e desenvolvimento de controladores ressonantes para um inversor m?dulo-integrado baseado no Conversor Zeta no MCD para a conex?o de pain?is PV ? rede el?trica

Levin, Gustavo Hoppe 31 August 2013 (has links)
Made available in DSpace on 2015-04-14T13:56:29Z (GMT). No. of bitstreams: 1 452976.pdf: 2671050 bytes, checksum: 99da8d60647852afabf102b73646c3cf (MD5) Previous issue date: 2013-08-31 / This work proposes the study and implementation of resonant controllers applied to photovoltaic panels grid-tied by a Zeta converter. This converter is designed to synthesize a rectified sinusoidal waveform current with low-harmonic content. Operating in discontinuous conduction mode, the Zeta Converter is connected to a full-bridge inverter so that one semi-cycle of the output current is inverted for every cycle of the power grid voltage, allowing the connection of PV panels to the power grid. The assembly formed by PV panel and inverter is known as Module-Integrated Inverter (MII). By aiming the project of resonant controllers, an analysis of the Zeta converter is presented, including its state-space model proposed in previous works. Furthermore, fundamental robust control concepts involved on the resonant controllers project are presented. In order to determine the gains of the resonant controllers, a formulation based on Linear Matrix Inequalities (LMIs) that guarantees the stability and performance of the closed-loop system is presented. A state-observer is also designed, reducing the number of variables that must be measured. Finally, the developed control strategy is validated through computational simulations and laboratorial tests on a prototype specially developed to this purpose. The results obtained by the experimental results validated the purpose, confirming the viability of using resonant controllers for this application, in order to synthesize a sinusoidal current waveform with low-harmonic content, synchronized with the power grid. / Este trabalho prop?e o estudo e a aplica??o de controladores ressonantes desenvolvidos para um Conversor Zeta, o qual foi concebido para sintetizar ? sua sa?da uma forma de onda de corrente senoidal retificada, com baixo conte?do harm?nico, visando desta forma o aproveitamento da energia gerada a partir de pain?is solares fotovoltaicos (PV). Operando no modo de condu??o descont?nuo, o conversor Zeta ? conectado em cascata a um inversor em ponte completa, visando inverter um dos semiciclos da sua corrente de sa?da a cada ciclo da tens?o da rede, permitindo assim a conex?o dos pain?is PV ? rede el?trica da concession?ria de energia. O conjunto formado por painel PV e inversor ? conhecido como Inversor M?dulo-Integrado. Visando o projeto dos controladores ressonantes, apresenta-se uma an?lise do Conversor Zeta, incluindo o modelo de espa?o de estados proposto em trabalhos anteriores. Em seguida, apresentam-se conceitos fundamentais de controle robusto envolvidos no projeto dos controladores ressonantes. Para determina??o dos ganhos dos controladores ressonantes, apresenta-se uma formula??o baseada em desigualdades matriciais lineares (LMIs). Um observador de estados tamb?m ? projetado, visando diminuir o n?mero de vari?veis a serem medidas. Logo depois, a metodologia de controle ? apresentada, acompanhada do projeto do observador de estados. Por fim, a estrat?gia de controle desenvolvida ? validada atrav?s de simula??es computacionais e atrav?s de ensaios laboratoriais em um prot?tipo especialmente elaborado para este fim. Os resultados obtidos experimentalmente validaram a proposta, resultando na s?ntese de uma forma de onda senoidal de corrente, com baixo conte?do harm?nico, sincronizada com a rede el?trica da concession?ria.
102

Ideais de anéis de operadores diferenciais / Ideals of rings of differential operators

Napoleon Caro Tuesta 07 April 2011 (has links)
Em [12] J.T. Stafford demonstrou que todo ideal à esquerda ou à direita da álgebra de Weyl \'A IND. n\' (K) = K \'[ \'x IND. 1\', ...,\'x IND. n\' ] \' partial IND. 1\', ... \'partial IND. n\' (K um corpo de característica zero) é gerado por dois elementos. Consideremos o anel \'D IND. n\' := K [[\'x IND.1\', ...\'x IND. n\']] de operadores diferenciais sobre o anel de séries de potências formais K[[\'x IND. 1\';...\' xI ND. n\']]. Uma pergunta natural é se todo ideal à esquerda ou à direita de\' D IND. n\'(K) pode ser gerado por dois elementos. Neste trabalho provaremos que todo ideal à esquerda ou à direita do anel \'E IND. n\'(K) := K((\'x IND. 1\' ... \'x IND. n\'))(\' partial IND. 1, ...\'partial IND. n\') de operadores diferenciais sobre o corpo das séries de Laurent K((\'x IND. 1\', ...\'x IND. n\')) é gerado por dois elementos. Nós provaremos também que todo ideal à esquerda ou à direita do anel \'S IND. n -1\'(K) := K((\'x IND. 1\', ...\'X ind. n - 1\"))[[\'x IND. n\']](\' partial IND. 1, ...\'partial IND. n\') é gerado por dois elementos e como corolário obtemos uma demonstração que todo ideal à esquerda ou à direita do anel \'D IND. 1\'(K) é gerado por dois elementos. Isto está de acordo com a conjectura que diz que todo ideal à esquerda ou à direita de um anel (não comutativo) Noetheriano simples é gerado por dois elementos / In [12] J.T. Stafford proved that every left or right ideal of the Weyl algebra \'A IND. n\'(K) = K[\'x IND. 1\', ...\'x IND. n\'](\' partial IND. 1, ...\'partial IND. n\')(K a field of characteristic zero) is generated by two elements. Consider the ring \'D IND. n\' := K[[\'x IND. 1\', ...\'x IND.n\']](\'partial IND. 1\", ...\'partial IND. n) of differential operators over the ring of formal power series K[[\'x IND. 1\', ... \'x IND. n\']]: A natural question is that if every left or right ideal of \'D IND. n\'(K) can be generated by two elements. In this work we will prove that every left or right ideal of the ring \'E IND. n\' (K) := K((\'x IND. 1\', ... \'x IND. n\'))(\'partial IND. 1,...\'partial IND. n\') of differential operators over the field of formal Laurent series K((\'x IND. 1\', ...\'x IND. n\'))) is generated by two elements. We will prove also that every left or right ideal of the ring \'S IND. n -1\"(K) := K((\'x IND. 1\', ...\'x IND. n\'-1\'))[[\'x IND. n]](\'paertial IND. 1, ...\'partial IND. n\') is generated by two elements and as a corollary we obtain a proof of that every left or right ideal of the ring \'D IND. 1\'(K) is generated by two elements. This is in accordance with the conjecture that says that in a (noncommutative) Noetherian simple ring, every left or right ideal is generated by two elements
103

Estudo e desenvolvimento de um m?todo de MPPT para sistemas PV, baseado na t?cnica P&O aplicado a um microinversor do tipo flyback

Rambo , Carlos Eduardo Bizarro 31 March 2015 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-11-24T11:47:18Z No. of bitstreams: 1 476372 - Texto Completo.pdf: 4077296 bytes, checksum: 85b4c453088ae9f0ceed3d18c8ad4570 (MD5) / Made available in DSpace on 2015-11-24T11:47:18Z (GMT). No. of bitstreams: 1 476372 - Texto Completo.pdf: 4077296 bytes, checksum: 85b4c453088ae9f0ceed3d18c8ad4570 (MD5) Previous issue date: 2015-03-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Funda??o de Amparo ? Pesquisa do Estado do Rio Grande do Sul - FAPERGS / This work presents the study and development of a modification proposal of the classical MPPT - P&O approach, based on the utilization of the power and voltage derivatives in PV panel terminals. The contribution of this study consists in the employment of the time derivative of voltage that is used to determine converter duty cycle step size instantly. The proposed MPPT approach when compared to the classical P&O, presents some advantages like as: better dynamic response, steady state error reduction and robustness (considering different irradiation and temperature profiles). In order to validate this study, a microinverter prototype based on flyback converter, using this new approach, was implemented aiming to connect PV panels to the mains. Microinverter control strategy was held on Matlab/Simulink? environment in association to a data processing board (DS1104 from dSPACE?). / Este trabalho apresenta o estudo e o desenvolvimento de uma proposta de modifica??o do m?todo de MPPT P&O cl?ssico com base na utiliza??o da derivada da pot?ncia e da derivada da tens?o nos terminais dos pain?is PV. A contribui??o deste trabalho consiste no emprego da derivada da tens?o dos pain?is, a qual ? utilizada para determinar a varia??o instant?nea do ciclo de trabalho do conversor. O m?todo de MPPT proposto em compara??o com o m?todo P&O convencional apresentou melhor desempenho considerando-se a resposta din?mica, o erro de estado estacion?rio e a robustez (contra diferentes perfis de irradi?ncia e de temperatura). A fim de validar este estudo, um prot?tipo de um microinversor com base no conversor flyback, usando a abordagem proposta, foi implementado com o objetivo de conectar pain?is fotovoltaicos ? rede el?trica. A estrat?gia de controle do microinversor foi realizada em ambiente Matlab/Simulink? em associa??o a uma placa de processamento de dados (DS1104 da dSPACE?).
104

Efficient and High-Yielding Routes to Diaryliodonium Salts

Bielawski, Marcin January 2008 (has links)
<p>This thesis summarizes three novel and general reaction protocols for the synthesis of diaryliodonium salts. All protocols utilize mCPBA as oxidant and the acids used are either TfOH, to obtain triflate salts, or BF3•Et2O that gives the corresponding tetrafluoroborate salts in situ.</p><p>Chapter two describes the reaction of various arenes and aryl iodides, delivering electron-rich and electron-deficient triflates in moderate to excellent yields.</p><p>In chapter three, it is shown that the need of aryl iodides can be circumvented, as molecular iodine can be used together with arenes in a direct one-pot, three-step synthesis of symmetric diaryliodonium triflates.</p><p>The final and fourth chapter describes the development of a sequential one-pot reaction from aryl iodides and boronic acids, delivering symmetric and unsymmetric, electron-rich and electron-deficient iodonium tetrafluoroborates in moderate to excellent yields. This protocol was developed to overcome mechanistic limitations existing in the protocols described in chapter two and three.</p><p>The methodology described in this thesis is the most general, efficient and high-yielding existing up to date, making diaryliodonium salts easily available for various applications in synthesis.</p>
105

Vardagslivet i hamnen : Djurhamns historia belyst med marinarkeologiskt material

Wiklund, Jonas January 2015 (has links)
Those who today hear the name Djurhamn are maybe first thinking of a summer resort place with sunbathing, swimming and recreational boating activities. Djurhamn has an interesting and fascinating history well intertwined with the history of Sweden. The interesting history was exposed by the Stockholm Sport Diving Club which, during the summers of 1964 and 1965, brought up a large number of finds from the bottom of Djurhamn. The findings could essentially be dated to be in the in the period 1500s to 1700s. Like other parts of the East Coast Djurhamn was hit in "Russian raids" in the early 1700s. The known meetings of warships during the Vasa era and the history of naval ship Riskswasas fate also reflects the interesting parts of Djurhamn history. While working on this, a number of dives were made at the bottom of the basin in Djurhamn. Two side-scan surveys have also been conducted. Overall, this has not resulted in any change of the picture of what's on Djurhamns bottom. A previously unknown wreck that lies south of the cemetery have, however, been located based on information from the public. The finds from the dives during 1964 and 1965 talk about food and drinks, cooking utensils, three-leg pots and bottles speaks their language. Even earlier dated bargain materials speak the same language. It is a place where everyday objects leave imprints on the bottom along with the testimony of a brickyard, which flourished for a short period. Which traces have been left from the naval activities? Practically none. On land there are no naval monuments. The objects which were brought up at the 1960 dives were almost entirely attributable to the applications connected to cooking. Our modern society is a complex reality. There are homes, workplaces, hospitals, places of entertainment, etc. People are born, grow up, grow old and die. What do we find in the signs of the Djurhamn? Well, a picture that much is a reflection of today's society. Also here you are born grown up grown old and finally dead. Heavy drinking has flourished. In addition to self-household and shipping, there has been brick industry and cholera quarantine. Finally, perhaps Djurhamn over time is best described as farmers, fishermen and hungry sailors’ history more than the history of the fleet in the Vasa kings’ service.
106

La catalyse hétérogène au palladium en chimie fine : une étude sur la synthèse " one-pot " de stilbènes et bibenzyles : application à la synthèse de styrènes et aryl-indoles

Cusati, Giuseppe 15 October 2009 (has links) (PDF)
Les synthèses " one pot " multi-étapes efficaces et éco-compatibles ont été envisagées pour la synthèse de molécules potentiellement bioactives tels que les systèmes bis(bibenzyliques) et leurs précurseurs stilbéniques ou bibenzyliques par catalyse hétérogène au palladium. Une synthèse " one-pot " impliquant une réaction de couplage de Heck suivie d'une hydrogénation des stilbènes ainsi formés a été mise au point en présence de Pd/C. Cette stratégie c'est révélée être limitée lors de l'application à des substrats désactivés et stériquement encombrées. Couplée au manque de disponibilité commerciale d'oléfines aromatiques intéressantes pour nos objectifs, nous avons mis au point une synthèse de styrènes par catalyse hétérogène à partir d'halogénures d'aryles et du vinyltrifluoroborate de potassium impliquant un couplage de Suzuki-Miyaura. Cette vinylation hétérogène a été ensuite appliquée à la synthèse " one-pot " de stilbènes. Des études d'optimisation de ce procédé sont encore en cours. Les stilbènes ainsi obtenus ont été utilisée pour la synthèse de bis(bibenzyles) ouverts et fermés. Pour ce faire différentes stratégies " one-pot " ont été évaluées au cours de ces travaux et des bis(stilbènes) ont été obtenus avec des rendements compris entre 30% et 50%. Les bis(stilbènes) ainsi obtenus ont été l'objet d'études en hydrogénation. A ce jour aucune de nos tentatives n'a permis l'obtention de bis(bibenzyles) quelles que soient les conditions employées. Des études sont en cours pour comprendre les raisons de ces résultats et obtenir les bis(bibenzyles) cibles de nos travaux
107

Observation, caractérisation et modélisation de processus d'attaques sur Internet

Alata, Eric 07 December 2007 (has links) (PDF)
Le développement de méthodes permettant l'observation et la caractérisation d'attaques sur Internet est important pour améliorer notre connaissance sur le comportement des attaquants. En particulier, les informations issues de ces analyses sont utiles pour établir des hypothèses réalistes et mettre en oeuvre des mécanismes de protection pour y faire face. Les travaux présentés dans cette thèse s'inscrivent dans cette optique en utilisant des pots de miel comme moyen pour collecter des données caractérisant des activités malveillantes sur Internet. Les pots de miel sont des systèmes informatiques volontairement vulnérables et visant à attirer les attaquants afin d'étudier leur comportement. Nos travaux et contributions portent sur deux volets complémentaires. Le premier concerne le développement d'une méthodologie et de modèles stochastiques permettant de caractériser la distribution des intervalles de temps entre attaques, la propagation et les corrélations entre les processus d'attaques observés sur plusieurs environnements, en utilisant comme support les données issues de pots de miel basse interaction d'eployés dans le cadre du projet Leurré.com. Le deuxième volet de nos travaux porte sur le développement et le déploiement d'un pot de miel haute interac- tion permettant d'étudier aussi la progression d'une attaque au sein d'un système, en considérant comme exemple des attaques visant le service ssh. L'analyse des données collectées nous a permis d'observer différentes étapes du processus d'intrusion et de montrer la pertinence de notre d'approche.
108

Sistema embarcado para monitoramento de circuitos auxiliares em disjuntores de pot?ncia de distribuidoras de energia el?trica

Cavalcante, S?rgio Gomes 28 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-06T21:17:06Z No. of bitstreams: 1 SergioGomesCavalcante_DISSERT.pdf: 2152523 bytes, checksum: 2c09534044f4a7214627c3d49f0aaa8e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-20T23:59:14Z (GMT) No. of bitstreams: 1 SergioGomesCavalcante_DISSERT.pdf: 2152523 bytes, checksum: 2c09534044f4a7214627c3d49f0aaa8e (MD5) / Made available in DSpace on 2017-11-20T23:59:14Z (GMT). No. of bitstreams: 1 SergioGomesCavalcante_DISSERT.pdf: 2152523 bytes, checksum: 2c09534044f4a7214627c3d49f0aaa8e (MD5) Previous issue date: 2017-07-28 / O modelo de sistema el?trico introduzido no Brasil no final da d?cada de 90 produziu um ambiente com alto grau de regula??o. A cria??o da Ag?ncia Nacional de Energia El?trica (ANEEL) e suas regras for?am os agentes envolvidos nesse sistema a sempre procurarem a modicidade tarif?ria com um n?vel elevado de qualidade do servi?o e qualidade do produto. Estas exig?ncias impostas ?s concession?rias de energia no Brasil fazem com que as empresas desenvolvam processos para uma melhoria constante, mas nem sempre essas estrat?gias s?o suficientes para garantir bons indicadores de qualidade. Por vezes o processo n?o mant?m uma sincronia ideal a ponto de evitar falhas em sua execu??o. Outras vezes, as falhas n?o est?o nos processos em si, mas nos pr?prios equipamentos. Como exemplo, podem ser citadas as programa??es de manuten??o preventiva que s?o desenvolvidas em alguns equipamentos de uma subesta??o. Ainda podem ser citadas, as falhas intempestivas que para serem corrigidas ? necess?rio que a informa??o correta, percorra os canais de comunica??o de forma r?pida e precisa chegando at? aos respons?veis pela manuten??o. Nem sempre as informa??es certas chegam aos setores respons?veis com rapidez e precis?o, somado a isso, estas informa??es n?o s?o armazenadas e catalogadas para analises futuras. O presente projeto tem como objetivo fundamental dotar os disjuntores, equipamentos do sistema de prote??o, de intelig?ncia, por meio de um sistema embarcado. Com esta associa??o, os disjuntores ser?o capazes de desempenhar suas funcionalidades com rapidez e assertividade nos dados gerados, podendo antecipar-se ?s falhas tornando o sistema el?trico mais confi?vel e seguro. / The Electric Power System model introduced in Brazil in the late 1990s produced a scenario with a high regulation level. The Ag?ncia Nacional de Energia El?trica (ANEEL) creation and its rules force the agents involved in that system to always seek the low tariffs with a high quality level of service and product quality. The requirements imposed on Brazilian Power Utilities result in the development of processes that allow a continuous improvement. Nevertheless, these strategies are not always sufficient to ensure good quality indicators. Many times, the processes do not hold a perfect synchrony to the point of avoiding execution failures. Other times, the failures are not in the processes, but in the equipment that are objective of the existence of the processes. As an example the preventive maintenance schedules that are developed in certain equipment of a Substation. Another example, unscheduled failures to be corrected is necessary that the correct information, scroll through the channels of communication to quickly and accurately reaching those responsible for maintenance. Correct information does not always reach the department quickly and accurately, but it is stored and cataloged for future analysis. This work aimed to reduce the DEC (Equivalent Duration of Interruption per Consumer Unit) indicator, improvement in maintenance planning and increase in the electrical installations? s safety level in a substation. By building an embedded system designed to monitor the main internal components of a circuit breaker. With the results achieved, it is concluded that the device provided in the project meets the objectives imposed, being able to perform its functions with speed and assertiveness in the data generated. The integration of this equipment into the circuit-breakers will allow anticipating the failures making the electrical system more reliable and safe.
109

Efeitos da laserterapia de baixa pot?ncia sobre a fadiga do m?sculo quadr?ceps de indiv?duos jovens / Effects of low-level laser therapy on fatigue quadriceps muscle of young individuals

Guimar?es, Andr? Osvaldo Brand?o 12 September 2013 (has links)
Made available in DSpace on 2014-12-17T14:44:17Z (GMT). No. of bitstreams: 1 AndreOBG_DISSERT.pdf: 1684956 bytes, checksum: c41e79b5cbd9d1d9c025e43fd25d68d0 (MD5) Previous issue date: 2013-09-12 / The objective of this study was to evaluate the effect of low laser power on the performance of anaerobic endurance of the quadriceps muscle in young subjects. Low-level laser therapy (LLLT) appears to decrease some indices of muscle fatigue. Most of these effects may be due to the influence of the laser on the muscles predominantly aerobic. Animal studies and clinical trials have already shown that the laser can improve the efficiency of mitochondrial metabolism for the resynthesis of adenosine triphosphate and thus slow down - or minimize, the deleterious effects of muscle fatigue. This research was characterized as an experimental study of the controlled clinical trial, randomized, blinded, attended by 93 volunteers, military, with ages between 18 and 19 years. The subjects were randomly allocated into three groups: Control (G1), Placebo (G2) and Laser (G3). All volunteers underwent an anthropometric assessment and a protocol Fatigue. This protocol was applied to an initial assessment (AV-1) for the collection of baseline data, and a final evaluation (AV-2). As the study variables, we used the blood lactate concentrations and indices of muscle power, as average power and peak velocity. The fatigue protocol consisted of a test of speed with twenty repetitions, performed on an exercise machine leg press 45? . In conclusion, it was found that, in this study, LLLT caused a significant increase in the Average of the Averages Powers, phase eccentric exercise in leg press 45? performed by young individuals / O objetivo desse estudo foi o de avaliar o efeito da aplica??o do laser de baixa pot?ncia (LBP) sobre o desempenho da resist?ncia anaer?bia do m?sculo quadr?ceps em sujeitos jovens. A terapia com laser de baixa pot?ncia parece diminuir alguns ?ndices da fadiga muscular. A maior parte desses efeitos pode ser consequ?ncia da influ?ncia do laser sobre os m?sculos predominantemente aer?bios. Os estudos em animais e ensaios cl?nicos anteriores mostraram que o laser pode melhorar a efic?cia do metabolismo mitocondrial para a ress?ntese da Adenosina Trifosfato e, assim, retardar - ou minimizar- os efeitos delet?rios da fadiga muscular. Esta pesquisa caracterizou-se como um estudo experimental do tipo ensaio cl?nico controlado, randomizado e cego, no qual participaram 93 volunt?rios, militares, com faixas et?rias entre 18 e 19 anos. Os sujeitos foram alocados randomicamente em tr?s grupos: Controle (G1), Placebo (G2) e Laser (G3). Todos os volunt?rios foram submetidos a uma avalia??o antropom?trica e a um Protocolo de Fadiga. Este protocolo foi aplicado em uma avalia??o inicial (AV-1), para coleta de dados de base, e em uma avalia??o final (AV-2). Como vari?veis do estudo, utilizamos as concentra??es de lactato sangu?neo e ?ndices de pot?ncia muscular, como pot?ncia m?dia e velocidade pico. O protocolo de fadiga consistiu em um teste de velocidade m?xima, com vinte repeti??es, realizado em uma m?quina do exerc?cio leg press 45? . Em conclus?o, verificou-se que, neste estudo, a LBP causou um incremento significativo (p=0,047) na m?dia das pot?ncias m?dias da fase exc?ntrica do exerc?cio leg press 45? realizado por indiv?duos jovens
110

Testes para a avalia??o da qualidade fisiol?gica de sementes de Moringa oleifera Lam

Medeiros, Maria Luiza de Souza 17 December 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-27T17:39:00Z No. of bitstreams: 1 MariaLuizaDeSouzaMedeiros_DISSERT.pdf: 778297 bytes, checksum: 3012a0a9e0e06a0f632900e02f88e311 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-29T20:16:49Z (GMT) No. of bitstreams: 1 MariaLuizaDeSouzaMedeiros_DISSERT.pdf: 778297 bytes, checksum: 3012a0a9e0e06a0f632900e02f88e311 (MD5) / Made available in DSpace on 2016-06-29T20:16:49Z (GMT). No. of bitstreams: 1 MariaLuizaDeSouzaMedeiros_DISSERT.pdf: 778297 bytes, checksum: 3012a0a9e0e06a0f632900e02f88e311 (MD5) Previous issue date: 2015-12-17 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A avalia??o do vigor de sementes ? um fator importante para a detec??o de lotes de sementes de alta qualidade, de modo que o desenvolvimento de procedimentos para avaliar o potencial fisiol?gico tem sido importante ferramenta dentro de programas de controle de qualidade de sementes. Nesse sentido, este trabalho teve como objetivo adequar as metodologias dos testes de envelhecimento acelerado, condutividade el?trica e lixivia??o de pot?ssio para a avalia??o do vigor de sementes de Moringa oleifera LAM.. Para tanto, quatro lotes de sementes foram submetidos aos testes de germina??o, emerg?ncia de pl?ntula, ?ndice de velocidade de emerg?ncia, primeira contagem de emerg?ncia, comprimento e massa seca de pl?ntulas e teste frio, para a sua caracteriza??o fisiol?gica, al?m dos testes de envelhecimento acelerado, condutividade el?trica e lixivia??o de pot?ssio. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repeti??es de 50 sementes, e as m?dias comparadas pelo teste de Tukey a 5% de probabilidade, sendo realizada a an?lise de regress?o polinomial no teste de condutividade el?trica. Para o teste de envelhecimento acelerado, foram estudados os per?odos de envelhecimento de 12, 24 e 72 horas, a 40, 42 e 45 ?C. Para o teste de condutividade el?trica, utilizou-se a temperatura de 25 ?C por per?odos de 4, 8, 12, 16 e 24 horas de imers?o, em 75 e 125 mL de ?gua destilada, utilizando-se 25 e 50 sementes e, para o teste de lixivia??o de pot?ssio, utilizou-se amostras de 25 e 50 sementes, colocadas em copos pl?sticos contendo 70 e 100 mL de ?gua destilada ? 25 ?C por per?odos de 1, 2, 3, 4, 5 e 6 horas. A partir dos resultados obtidos, pode-se inferir que as metodologias que melhor se ajustaram para o teste de envelhecimento acelerado em sementes de moringa foram a temperatura de 40 ?C por 12 e 72 horas, 42 ?C a 72 horas e 45 ?C a 24 horas. Para o teste de condutividade el?trica em sementes de moringa, a combina??o de 50 sementes em 75 mL de ?gua destilada por per?odo de embebi??o de 4 horas e, 50 sementes em 125 ml por 4 horas foram eficiente para a diferencia??o dos lotes de sementes de moringa quanto ao vigor e, para o teste de lixivia??o de pot?ssio em sementes de moringa, a combina??o de 50 sementes /100 mL de ?gua destilada permitiu a separa??o dos lotes em quatro n?veis de vigor, a partir de 2 horas de imers?o, mostrando-se promissor na avalia??o da qualidade de sementes de moringa. / The evaluation of seed vigor is an important factor for detection of lots of high quality seeds, so that development of procedures to evaluate the physiological potential has been an important tool in quality control programs seeds. In this sense the study aimed to adapt the methodologies of accelerated aging, electrical conductivity and potassium leaching to evaluate Moringa oleifera seed vigor LAM.. Therefore, four lots of moringa seeds were subjected to the germination tests, seedling emergence, speed of emergence index, emergence first count, length and dry mass of seedlings and cold test for their physiological characterization, in addition to accelerated aging, electrical conductivity and potassium leaching. The experimental design was completely randomized with four replications of 50 seeds and the means compared by Tukey test at 5% probability. For accelerated aging the periods were studied aging 12, 24 and 72 hours at 40, 42 and 45?C. For the electrical conductivity test was used to a temperature of 25?C for periods of 4, 8, 12, 16 and 24 hours of immersion in 75 to 125 mL of distilled water, using 25 to 50 seeds, and for potassium leaching test samples were used 25 to 50 seeds, placed in plastic cups containing 70 and 100 mL of distilled water at 25?C for periods of 1, 2, 3, 4, 5 and 6 hours. From the results obtained, it can be inferred that the methods best fit for the accelerated aging test Moringa seeds were a temperature of 40?C for 12 to 72 hours, 42?C 72 hours 45?C 24 hours . In the electrical conductivity test Moringa seeds, the combination of 50 seeds in 75 mL distilled water for a period of immersion of 4 hours and 50 seeds in 125 mL of 4 hours were efficient for the differentiation of lots of Moringa seeds as to vigor and for potassium leaching test moringa seeds, the combination of 50 seeds in 100mL of distilled water allowed the separation of lots of four levels of vigor, at 2 hours of immersion, showing promise in evaluate the quality of moringa seeds.

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