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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.
11

Estudo Fitoqu?mico de Justicia wasshauseniana (Acanthaceae), Tetrapterys acutifolia e Lophanthera lactescens (Malpighiaceae) e Atividades biol?gicas / Phytochemical study of Justicia wasshauseniana (Acanthaceae), Tetrapterys acutifolia and Lophanthera lactescens (Malpighiaceae) and Biological activities

Fernandes, Renata Duarte 13 December 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-09-08T13:08:22Z No. of bitstreams: 1 2016 - Renata Duarte Fernandes.pdf: 6635666 bytes, checksum: ab405bd813ed887b89c988abc6b8f7ea (MD5) / Made available in DSpace on 2017-09-08T13:08:22Z (GMT). No. of bitstreams: 1 2016 - Renata Duarte Fernandes.pdf: 6635666 bytes, checksum: ab405bd813ed887b89c988abc6b8f7ea (MD5) Previous issue date: 2016-12-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This work describes the isolation and structural determination of special metabolites isolated from leaf and stem of J. wasshauseniana (Acanthaceae), popularly known as a coati tail, which was collected in the Paracambi, RJ; Leaves and stem of T. acutifolia (Malpighiaceae), popularly known as cip?-ro?o, were collected in the Barra do Pira?-RJ and leaf and bark of L. lactescens (Malpighiaceae), popularly known as lain of lold, was collected on the campus of the Federal Rural University of Rio de Janeiro Campus Serop?dica RJ. Some chemical and biological activities of extracts of the last species were evaluated. Chromatographic fractionation of leaf and stem extracts from the Justicia wasshauseniana (Acanthaceae), from the leaf and stem of Tetrapterys acutifolia (Malpighiaceae), and from the leaves and bark of Lophanthera lactescens (Malpighiaceae) besides analysis of fractions by chromatographic and spectroscopic techniques led to the isolation and identification of constituents of different classes of special metabolites. including new alkaloids from J. wasshauseniana. From the leaves and stem of J. wasshauseniana were identified a triglyceride with the unsaturated acyl moiety, an unsaturated carboxylic acid, a mixture of steroids (?-Sitosterol, estigmasterol and campesterol) and glycosyl steroids (3-O-?-D-glucopyranosylsitosterol and 3-O-?-D-glucopyranosylstgmasterol), a disaccharide (?-D-glucopyranosyl-O-?-D-fructofuranoside (Sucrose) and the alkaloids acid (N-fenil-o-metileno-O-5)-3-hidroxi-5-carboxy??-lactam, and N(fenil-o-metileno-O-5)-3-hidroxi-5-(carboxilato de 2,3-dihidroxipropionila)-?-lactama), described for the first time in the literature. From the leaves and stem of T. acutifolia were identified a mixture of sitosterol, stigmasterol, 5,6-dihydro-sitosterol. and 5,6-dihydro-20-21,22-23,24-28,25-26-campesterol, ascorbic acid, in addition to sucrose and an ecdysteroid, 2S,3R,5R,9R,10R,13R,14S,17S,20S-2,3,14,20,24,25-hexahidroxicolest-7-en-6-ona (Pinatasterone). The extracts from the leaves and barks of L. lactescens, besides the mixture of sitosterol, stigmasterol and campesterol, was isolated the nortriterpene known as coreolidene. Besides to confirm the structure correction proposed in the literature of this nortriterpene, the absolute stereochemistry was defined as methyl 4R,5R,6R,7S,8S,9S,10S,13R,14S,15S,16R,17S,18R,21S,22S-friedelan-1,2-en-3-carboxy-24- 5- [1-acetoxy-ethylidene] -6,7,15,16-tetracetoxy-18-hydroxy-21,22-oxy-29-methylene-30-carboxylate. The structures were defined through analysis of IR, 1D and 2D NMR, mass spectra and circular dichroism besides some methyl and acetyl derivatives. The methanolic extracts from the stem and leaves of J. wasshausseniana and the methanolic extracts and fractions of the stem and leaves of T. acutilfolia were tested against the free radicals of DPPH. The extract from the stem of J. wasshausseniana was more active than leaf extract. The fraction of hexane from the leaves of T. acutilfolia did not present a good antioxidant activity, a greater activity was observed for the ethyl acetate fraction of stem and leaves of this plant. The pharmacological tests of the antinociceptive and anti-inflammatory potentials of the L. lactescens bark methanolic extract and the methanolic extract of leaves of J. wassahueniana were carried out, in which they showed positive results in the tested activities. / Este trabalho descreve o isolamento e determina??o estrutural de metab?litos especiais isolados de folhas e caule de J. wasshauseniana (Acanthaceae), vulgarmente conhecida como rabo de quati, que foi coletada no Munic?pio de Paracambi, RJ; folhas e caule de T. acutifolia, conhecida vulgarmente como cip?-ru?o, coletado no munic?pio de Barra do Pira?-RJ e L. lactescens (Malpighiaceae), conhecida vulgarmente como Chuva-de-Ouro, coletado no campus da Universidade Federal Rural do Rio de Janeiro Campus Serop?dica RJ. Realizaram-se testes de atividade biol?gica de extratos das duas ?ltimas esp?cies. O fracionamento cromatogr?fico dos extratos de folhas e caule de Justicia wasshauseniana (Acanthaceae), de folhas e caule de Tetrapterys acutif?lia (Malpighiaceae), de folhas e cascas de Lophanthera lactescens (Malpighiaceae) e an?lise das fra??es atrav?s de t?cnicas cromatogr?ficas e espectrosc?picas conduziu ao isolamento e identifica??o de constituintes de diferentes classes de metab?litos especiais. Das folhas e caule de J. wasshauseniana foram identificados um triglicer?deo com a unidade acila insaturada, um ?cido carbox?lico insaturado, uma mistura dos ester?ides (?-sitostesterol, estigmasterol e campesterol) e a mistura de esteroides glicosilados, 3-O-?-D-glicopiranosilsitosterol e o 3-O-?-D-glicopiranosilestigmasterol, um dissacar?deo, ?-D-glicopiranosil-?-D-frutofuranos?deo (sacarose) e os alcal?ides ?cido-(N-fenil-o-metileno-O-5)-3hidroxi-5-carboxi??-lactama e N(fenil-o-metileno-O-5)-3-hidroxi-5-(carboxilato de 2,3-dihidroxipropionila)-?-lactama) que est?o sendo descritos pela primeira vez na literatura. Dos extratos de folhas e caule de T. acutifolia foram isolados uma mistura dos esteroides, sitostesterol, estigmasterol, 5,6-diidro-sitosterol e 5,6-diidro-20-21,22-23,24-28,25-26-octaidro-campesterol, o ?cido asc?rbico, al?m da sacarose e o ecdisteroide 2S,3R,5R,9R,10R,13R,14S,17S,20S-2,3,14,20,24,25-hexahidroxicolest-7-en-6-ona (Pinatasterona), desta enona que foi convertido em 2,3,24,25-tetraacetato atrav?s de tratamento com anidrido ac?tico e piridina. Dos extratos de folhas e cascas de L. lactescens, al?m da mistura de esteroides sitoesterol, estigmasterol e campesterol, foi isolado o nor-triterpeno conhecido como correolideo que, al?m da confirma??o da corre??o da estrutura registrada na literatura foi proposta a estereoqu?mica absoluta, sendo, entretanto definida como 4R,5R,6R,7S,8S,9S,10S,13R,14S,15S,16R,17S,18R,21S,22S-friedelan-1,2-en-3-carboxi-24-O-metileno-5-[1-acetoxi-etilideno]-6,7,15,16-tetracetoxi-18-hidroxi-21,22-oxi-29-metileno-30-carboxilato de metila. As estruturas foram definidas atrav?s de an?lise de espectros de IV, RMN 1D e 2D, massas e dicro?smo circular e, em alguns casos da prepara??o de derivados. Os extratos metan?licos de caule e de folhas de J. wasshausseniana e os extratos metan?licos e fra??es do caule e folhas de T. acutilfolia foram testados contra os radicais livres de DPPH. O extrato do caule de J. wasshausseniana apresentou melhor atividade do que o extrato de folhas. A fra??o de hexano de folhas de T. acutilfolia n?o apresentou uma boa atividade antioxidante, observando-se uma maior atividade para a fra??o de acetato de etila de caule e folhas. Realizaram-se os testes farmacol?gicos do potencial antinociceptivo e anti-inflamat?rio do extrato metan?lico de cascas de L. lactescens e extrato metan?lico de folhas de J. wassahueniana, no qual apresentaram resultados positivos nas atividades testadas
12

Investiga??o Te?rica de Rea??es Unimoleculares da Formamida em Fase Gasosa. / Theoretical Investigation of Unimolecular Reaction of Formamide in the Gas Phase.

Berutti Neto, Renato 14 March 2012 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2018-03-15T14:04:44Z No. of bitstreams: 1 2012 - Renato Berutti Neto.pdf: 4059567 bytes, checksum: 6f8cfef981af15e4298a546d0c7563dc (MD5) / Made available in DSpace on 2018-03-15T14:04:44Z (GMT). No. of bitstreams: 1 2012 - Renato Berutti Neto.pdf: 4059567 bytes, checksum: 6f8cfef981af15e4298a546d0c7563dc (MD5) Previous issue date: 2012-03-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / This work has been performed at the Laboratory of Chemical Kinetics, located in the Chemistry Department of Universidade Federal Rural do Rio de Janeiro, for the study of unimolecular reactions of formamide in gas phase and on the ground state: (1) CHONH2? CO + NH3 (2) CHONH2? H2 + HNCO and (3) CHONH2? HCO + NH2. Theoretical calculations including geometry optimizations and frequencies, have been performed at CASSCF level, with corrections at MRMP2 level for the electronic energy. The cc-pVDZ, cc and cc-pVTZ basis sets as well as the aug-cc-pVDZ have been used for comparative purposes. The unimolecular reactions were differently treated, depending on the specific topology of the potential energy surface. For the decompositions, corresponding saddle points have been located and the lowest energy paths have been calculated with the intrinsic reaction coordinate (IRC) method. The dissociation reaction has been described in terms of a scanning on the potential curve considering partial geometry optimizations of the fragments NH2 and HCO, keeping the CN distances frozen, those assumed as the internal reaction coordinate. Ab initio calculations were performed with the package GAMESS. The results show that the best description of the molecule has been obtained at CAS(10,9)/CCT level, yielding minimum deviations for the calculated molecular properties in relation to the experimental data available in the literature. The critical energies for the reactions of the decomposition have been determined, being (1): 77.60 kcal / mol and (2): 73.56 kcal / mol, both at level MRMP2/CAS(10,9)/CCT. For these results, it has been observed that the corrections MRMP2 are very important, bringing data calculated values very close to the literature values. From the analysis of the reaction pathways, it can be inferred that the dynamics of decomposition CHONH2 ? CO + NH3 is initiated by the torsional movement along the axis molecular by slightly rotating the fragment HCO in relation to the NH2, while the distance CN extends and the HC distance increases, with decreasing of HCN angle; the hydrogen atom bonds to the nitrogen atom and, with progressive increase of the distance CN, the fragments NH3 and CO are formed, achieving relaxed geometries. The decomposition CHONH2? HNCO + H2, by its turn, is initiated by increasing the distance HC at the HCO fragment, and further hydrogen abstraction of the atom at the NH2 fragment to form H2, which progressively separates from the HNCO, after the saddle point, generating the two products of this reaction. Dissociation is interpreted as the stretching of the CN bond, which promotes the separation of the NH2 and HCO fragments, whose geometries are relaxed along the curve of potential. The dissociation limit, determined at level MRMP2/CAS(10,9)/CCT is 91.52 kcal/mol. The canonical variational constant were calculated in the range of 300 - 2000K, being the values, in s-1, obtained at 1600K: (1) k = 5.62 x 103, (2) k = 1.07 x 103 and (3) k = 3.45. It follows that the channel (1) is privileged at a temperature of 1600K, and the decompositions are faster than the dissociation. / O presente trabalho foi realizado no Laborat?rio de Cin?tica, situado no Departamento de Qu?mica da Universidade Federal Rural do Rio de Janeiro, visando o estudo das Rea??es Unimoleculares da Formamida em Fase Gasosa e no Estado Fundamental: (1) CHONH2? CO + NH3, (2) CHONH2? HNCO + H2 e (3) CHONH2? HCO + NH2. C?lculos te?ricos, incluindo otimiza??es de geometria e frequ?ncias, foram procedidos em n?vel CASSCF com corre??es em n?vel MRMP2 para a energia eletr?nica. Bases cc-pVDZ e cc-pVTZ, assim como aug-ccpVDZ foram utilizados para fins comparativos. As rea??es unimoleculares foram tratadas diferentemente, dependendo da topologia espec?fica da superf?cie de energia potencial. Para as decomposi??es, pontos de sela correspondentes foram localizados e caminhos de menor energia foram calculados com o m?todo da coordenada de rea??o intr?nseca (IRC). A rea??o de dissocia??o foi descrita a partir do levantamento da curva de potencial considerando otimiza??es parciais de geometria dos fragmentos NH2 e HCO, mantendo fixas as dist?ncias CN, coordenada interna esta, assumida como a coordenada de rea??o. Os c?lculos ab initio foram realizados com o pacote GAMESS. Os resultados mostram que a melhor descri??o da mol?cula de formamida foi obtida em n?vel CAS(10,9)/CCT, promovendo menores desvios das propriedades moleculares calculadas em rela??o as experimentais dispon?veis na literatura. As energias cr?ticas para as rea??es de decomposi??o foram determinadas, sendo (1): 77,60kcal/mol e (2): 73,56 kcal/mol, ambas em n?vel MRMP2/CAS(10,9)/CCT. Para esses resultados, observou-se que as corre??es MRMP2 foram muito importantes, trazendo esses dados calculados a valores muito pr?ximos aos recomendados na literatura. A partir da an?lise dos caminhos de rea??o, pode-se inferir que a din?mica da decomposi??o CHONH2? CO + NH3 ? iniciada pelo movimento de tor??o ao longo do eixo molecular, fazendo girar levemente o fragmento NH2 em rela??o ao HCO, ao mesmo tempo em que o eixo CN se alonga e a dist?ncia HC aumenta, com a diminui??o do ?ngulo HCN, o ?tomo de hidrog?nio se liga ao nitrog?nio e, a partir do aumento progressivo da dist?ncia CN, os fragmentos NH3 e CO se formam, tendo lentamente suas geometrias relaxadas. J? a decomposi??o CHONH2? HNCO + H2 ? iniciada pelo aumento da dist?ncia HC no radical HCO e posterior abstra??o de um dos ?tomos de hidrog?nio do fragmento NH2 para a forma??o de H2, que se distancia progressivamente, ap?s a regi?o do ponto de sela, do fragmento HNCO, gerando os dois produtos desta rea??o. A dissocia??o, interpretada como o estiramento da liga??o CN, promove a separa??o dos fragmentos NH2 e HCO, cujas geometrias s?o otimizadas ao longo da curva de potencial. O limite de dissocia??o, calculado em n?vel MRMP2/CAS(10,9)/CCT foi determinado como 91,52 kcal/mol. As constantes variacionais can?nicas foram calculadas na faixa de 300 - 2000K com o programa kcvt, sendo os valores, em s-1, obtidos a 1600K: (1) k = 5,62 x 103, (2) k = 1,07 x 103 e (3) k = 3,45. Conclui-se que o canal (1) ? privilegiado na temperatura de 1600K, e que as decomposi??es s?o mais r?pidas que a dissocia??o.
13

S?ntese e avalia??o da atividade anticorrosiva d enamino?steres frente ao a?o carbono AISI 1020 em meio ?cido / Synthesis and evaluation of the anti-corrosive activity of enantiomers against AISI 1020 carbon steel in acidic medium

Carlos, Mariana Falc?o Lopes Princisval 16 August 2017 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-04-11T16:46:38Z No. of bitstreams: 1 2017 - Mariana Falc?o Lopes Princisval Carlos.pdf: 3027874 bytes, checksum: f7dd2c459e8918f917f701198c97f955 (MD5) / Made available in DSpace on 2018-04-11T16:46:38Z (GMT). No. of bitstreams: 1 2017 - Mariana Falc?o Lopes Princisval Carlos.pdf: 3027874 bytes, checksum: f7dd2c459e8918f917f701198c97f955 (MD5) Previous issue date: 2017-08-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In this work, seven enaminoesters were synthesized, divided into three series depending on the starting amine, the series A is derived from phenethylamine, the series B of aniline and, finally, the series C derived from benzylamine. The synthesis occurred in two ways, the first being through the reaction of the ethyl acetoacetate in the presence of the corresponding amine in ethanol as solvent in the presence of p-toluenesulfonic acid and the second the amine in the presence of triethylamine and methanol as solvent, both in magnetic stirring at room temperature. The compounds were obtained as oil, with a high purity, and for some compounds separation via flash chromatography in ethyl acetate / hexane was required, yields ranging from 70-93%. The compounds were characterized by spectroscopic techniques such as Infrared and Nuclear Magnetic Resonance 1H and 13C, in addition to the refractive index. Six of the seven compounds synthesized were evaluated using electrochemical techniques of Impedance Spectroscopy Electrochemistry, Potentiodynamic Polarization and Resistance to Linear Polarization and the mass loss technique, as to the action as inhibitors of corrosion against AISI 1020 carbon steel in 0.5 mol L-1 HCl. The Molecular Modeling technique was used to better visualize the structures of the synthesized enaminoesters and, later, correlation of the inhibition efficiencies found. The theoretical parameters such as the energy of the orbitals of symmetrical boundaries and dipole moment with the results corrosion efficiency were also evaluated. In general, the enaminoesters showed good corrosion efficiency, excess by the compound derived from hydroxylaniline. All presented corrosion inhibition efficiency with mixed inhibitor characteristics. However, the compounds that did not present substituents and those that contain electron donor group (OCH3) stood out as inhibitors, highlighting the compound EN1, which presented efficiency of 92% of inhibition of the corrosion by the technique of Resistance to Polarization Potentiodynamics and 98% by the technique of mass loss after 24h of immersion. The efficiency was shown to be dependent on the concentration in the synthesized compounds, that is, the corrosion inhibition efficiency increases with XXIII increasing inhibitor concentration, and that the adsorption phenomena of the compounds studied obey the Langmuir isotherm. Thus, the synthesized, especially the not substituted, enaminoesters can be considered as promising corrosion inhibiting agents for acidic AISI 1020 carbon steel. / Nesta disserta??o, foram sintetizados sete enamino?steres, divididos em tr?s s?ries de acordo com a amina de partida, sendo a s?rie A derivada da fenetilamina, a s?rie B da anilina e, por ?ltimo, a s?rie C derivada da benzilamina. A s?ntese ocorreu de duas formas, sendo a primeira atrav?s da rea??o do acetoacetato de etila na presen?a da amina correspondente em etanol como solvente, na presen?a de ?cido p-toluenossulf?nico e, a segunda, a amina na presen?a de trietilamina e metanol como solvente, ambas em agita??o magn?tica ? temperatura ambiente. Os compostos foram obtidos em forma de ?leo, com alto grau de pureza, sendo necess?ria para alguns compostos a separa??o via cromatografia flash em acetato de etila/hexano, os rendimentos variaram na faixa de 70-93%. Os compostos foram caracterizados por t?cnicas espectrosc?picas de Infravermelho e Resson?ncia Magn?tica Nuclear 1H e 13C, al?m de ?ndice de refra??o. Seis dos sete compostos sintetizados foram avaliados por t?cnicas eletroqu?micas de Espectroscopia de Imped?ncia Eletroqu?mica, Polariza??o Potenciodin?mica e Resist?ncia a Polariza??o Linear e, por ensaio de perda de massa, quanto ? a??o como inibidores de corros?o frente a a?o carbono AISI 1020 em solu??o de HCl 0,5 mol L-1 . Modelagem Molecular foi utilizada para melhor visualiza??o das estruturas moleculares dos enamino?steres sintetizados e, posterior, correla??o das efici?ncias de inibi??o encontradas. Os par?metros te?ricos como a energia dos orbitais de fronteiras sim?tricos e momento dipolar foram calculados e, apenas os valores de momento dipolar correlacionaram com os resultados experimentais da efici?ncia anticorrosiva. De forma geral, os enamino?steres apresentaram boa efici?ncia anticorrosiva, com exce??o do composto derivado da hidr?xianilina (EN6). Todos apresentaram efici?ncia de inibi??o ? corros?o com caracter?sticas de inibidores mistos. Por?m, os compostos que n?o apresentaram substituintes e os que cont?m grupo doador de el?trons (OCH3) se destacaram como inibidores mais eficientes, dando destaque ao composto EN1, que apresentou efici?ncia de 92% de inibi??o da corros?o, pela t?cnica de Resist?ncia a Polariza??o Potenciodin?mica e 98% pela t?cnica de perda de massa ap?s 24 h de imers?o. XXI A efici?ncia se mostrou dependente da concentra??o nos compostos sintetizados, ou seja, a efici?ncia de inibi??o da corros?o aumentou com o aumento da concentra??o dos inibidores. Os fen?menos de adsor??o dos compostos estudados, apenas o EN1 obedece ? isoterma de Langmuir e os restantes a Langmuir modificada. Com isso, os enamino?steres sintetizados, especialmente os n?o substitu?dos, podem ser considerados como promissores agentes inibidores da corros?o para o a?o carbono AISI 1020 em meio ?cido.
14

Buraco negros, correspond?ncia AdS/BCFT e fluido/gravidade / Black hole, AdS/BCFT and fluid/gravity correspondences

Silva, Madson Rubem Oliveira 22 May 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-22T19:28:11Z No. of bitstreams: 1 MadsonRubemOliveiraSilva_TESE.pdf: 1495464 bytes, checksum: 0d35c3d788f1373d1f29cb97ab81c05a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-23T23:12:57Z (GMT) No. of bitstreams: 1 MadsonRubemOliveiraSilva_TESE.pdf: 1495464 bytes, checksum: 0d35c3d788f1373d1f29cb97ab81c05a (MD5) / Made available in DSpace on 2016-03-23T23:12:57Z (GMT). No. of bitstreams: 1 MadsonRubemOliveiraSilva_TESE.pdf: 1495464 bytes, checksum: 0d35c3d788f1373d1f29cb97ab81c05a (MD5) Previous issue date: 2015-05-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / A equa??o de Einstein com constante cosmol?gica negativa gera um espa?o-tempo d + 1?dimens?es, que denominamos de espa?o anti de Sitter, AdSd+1, que nos referimos de "bulk". O principio hologr?fico afirma que a gravidade qu?ntica sobre o AdSd+1 ? codificada por uma teoria de contorno, uma CFTd. Por exemplo, uma teoria de cordas IIB sobre uma espa?o-tempo assintoticamente AdS5 ? S 5 ? dual a uma teoria de gauge de super Yang-Mills N = 4 SYM no espa?o-tempo de 4?dimens?es. Outro exemplo ? a rela- ??o entre a equa??o de Einstein no "bulk"e a equa??o hidrodin?mica descreve uma teoria efetiva no contorno, o qual denominamos de fluido/gravita??o. Uma extens?o da dualidadeAdS/CFT foi proposta por Takayanagi que denominou de correspond?ncia AdS/BCFT. O contorno do CFT extende-se para o "bulk"e restringe o AdSd+1. Quando impomos a condi??o de Neumann sobre a extens?o do contorno obtemos uma equa??o de movimento din?mica que determina a forma da extens?o. Da perspectiva da correspond?ncia fluido/gravita??o o tensor energia-momento do fluido residindo no contorno ser? a fonte da geometria do "bulk". Ampliando a proposta de Takayanagi para correspond?ncia fluido/gravita??o estudaremos a consist?ncia do AdS/BCFT a temperatura finita ou equivalentemente a geometria de BH no "bulk". / Einstein?s equations with negative cosmological constant possess the so-called anti de Sitter space, AdSd+1, as one of its solutions. We will later refer to this space as to the "bulk". The holographic principle states that quantum gravity in the AdSd+1 space can be encoded by a d?dimensional quantum field theory on the boundary of AdSd+1 space, invariant under conformal transformations, a CFTd. In the most famous example, the precise statement is the duality of the type IIB string theory in the space AdS5 ? S 5 and the 4?dimensional N = 4 supersymmetric Yang-Mills theory. Another example is provided by a relation between Einstein?s equations in the bulk and hydrodynamic equations describing the effective theory on the boundary, the so-called fluid/gravity correspondence. An extension of the "AdS/CFT duality"for the CFT?s with boundary was proposed by Takayanagi, which was dubbed the AdS/BCFT correspondence. The boundary of a CFT extends to the bulk and restricts a region of the AdSd+1. Neumann conditions imposed on the extension of the boundary yield a dynamic equation that determines the shape of the extension. From the perspective of fluid/gravity correspondence, the shape of the Neumann boundary, and the geometry of the bulk is sourced by the energy-momentum tensor T?? of a fluid residing on this boundary. Clarifying the relation of the Takayanagi?s proposal to the fluid/gravity correspondence, we will study the consistence of the AdS/BCFT with finite temperature CFT?s, or equivalently black hole geometries in the bulk.
15

Sistema de infer?ncia Fuzzy para estimativa da umidade do solo sob influ?ncia do teor de mat?ria org?nica / Fuzzy inference system for estimating the soil moisture under the influence of organic matter content

Triani, T?rcio de Sampaio 22 June 2015 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-01T11:43:57Z No. of bitstreams: 1 2015 - T?rcio de Sampaio Triani.pdf: 2326230 bytes, checksum: 297ea4ee1d9f2251260ab1c73fb44502 (MD5) / Made available in DSpace on 2017-06-01T11:43:57Z (GMT). No. of bitstreams: 1 2015 - T?rcio de Sampaio Triani.pdf: 2326230 bytes, checksum: 297ea4ee1d9f2251260ab1c73fb44502 (MD5) Previous issue date: 2015-06-22 / The study of soil water dynamics has been growing across the need to optimize the use of water resources for the maintenance of agricultural productivity. In order to assist this study, different models of soil water dynamics has been created and studied in an attempt to predict situations that empirically become time-consuming and expensive. The soil water dynamics is directly associated with physical and hydric parameters, as well as the soil moisture. To determine the soil moisture, there are techniques that require a large amount of samples, increasing the cost and time required to perform such measurements.This work continues the dissertation of Belleza. A model based on fuzzy rules to estimate the moisture in topsoil from soil texture data, matric potential and amount of organic matter is elaborated. The distinction and analysis made by the model fall under the influence of organic matter on the soil water retention, disregarded by most studies of this type. The data set used for training and validation of the model comes from a research project conducted in the Amazon region, organized in a report funded by Petrobras. The results, obtained by simulation performed in the software Matlab, show that the organic matter has great influence in soil water retention of soils which clay content is under 35%. A significant decrease of total mean error in relation with the work of Belleza, which ignores the influence of organic matter, is observed. The increase in the number of the fuzzy inference system rules also allow a better approximation of the estimated values to the real moisture values. Taking into account the uncertainties inherent to the phenomenon this model is considered appropriate, due to its simplicity and relatively low average of errors, and an evolution in the field of modeling the soil moisture estimation by fuzzy logic. / O estudo da din?mica da ?gua no solo tem sido crescente frente ? necessidade de otimiza??o de uso de recursos h?dricos para a manuten??o da produtividade agr?cola. Como forma de auxiliar esse estudo, diferentes modelos de din?mica da ?gua no solo t?m sido criados e estudados, em uma tentativa de se prever situa??es que empiricamente se tornam demoradas e custosas. A din?mica da ?gua no solo est? associada diretamente a par?metros f?sico-h?dricos do solo, assim como a umidade do solo. Para se determinar a umidade do solo existem t?cnicas que necessitam de uma grande quantidade de amostragens, elevando o custo e o tempo necess?rio para realizar tais medi??es. Este trabalho d? continuidade ? disserta??o de Belleza. ? elaborado um modelo baseado em regras fuzzy para estimar a umidade em camadas superficiais do solo a partir de dados de textura do solo, potencial matricial e quantidade de mat?ria org?nica. A distin??o e an?lise feitos pelo modelo recaem sobre a influ?ncia da mat?ria org?nica sobre a reten??o de umidade pelo solo, desconsiderada pela maioria dos trabalhos deste tipo. O conjunto de dados utilizado para treinamento e valida??o do modelo ? proveniente de um projeto de pesquisa realizado na regi?o amaz?nica, organizado em relat?rio financiado pela Petrobras. Os resultados, obtidos atrav?s de simula??o realizada no software Matlab, demonstram que a mat?ria org?nica possui grande influ?ncia na reten??o de umidade por solos cujo teor de argila esteja abaixo de 35%. ? observada uma redu??o significativa do erro absoluto m?dio total em rela??o ao trabalho de Belleza, que desconsidera a influ?ncia da mat?ria org?nica. O aumento do n?mero de regras do sistema de infer?ncia fuzzy permite tamb?m uma melhor aproxima??o das estimativas do valor real de umidade. Levando em conta as incertezas inerentes ao fen?meno este modelo ? considerado adequado devido a sua simplicidade e m?dia de erros relativamente baixa, e uma evolu??o no campo da modelagem da estimativa de umidade do solo por l?gica fuzzy.
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Uma proposta de ensino de c?nicas com o aux?lio do GeoGebra / A proposal of teaching conics with the help of GeoGebra

Gon?alves, Alan Jorge Ciqueira 31 August 2015 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-08T12:58:44Z No. of bitstreams: 1 2016 - Alan Jorge Ciqueira Gon?alves.pdf: 2968550 bytes, checksum: c41aeac563a3e880f387fa38231d62f7 (MD5) / Made available in DSpace on 2017-06-08T12:58:44Z (GMT). No. of bitstreams: 1 2016 - Alan Jorge Ciqueira Gon?alves.pdf: 2968550 bytes, checksum: c41aeac563a3e880f387fa38231d62f7 (MD5) Previous issue date: 2015-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aims to improve understanding of studies of conics. For this, we will use as theoretical foundation in the construction of the proposed activities, the geometric constructivist theory of Van Hiele. Moreover, in line with the new teaching, and learning tools, we use a dynamic geometry software, the GeoGebra / Este trabalho tem por objetivo melhorar a compreens?o do estudo de c?nicas. Para isto, usaremos como fundamenta??o te?rica na constru??o das atividades propostas a teoria construtivista geom?trica de Van Hiele. Al?m disso, em conson?ncia com as novas ferramentas de ensino e aprendizagem, utilizaremos um software de geometria din?mica, GeoGebra.
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A utiliza??o dos jogos lot?ricos para o ensino de probabilidade no ensino m?dio / The use of lotteries to Probability Teaching in High School

Nunes, Victor Arantes 30 July 2015 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-14T11:55:01Z No. of bitstreams: 1 2015 - Victor Arantes Nunes.pdf: 1279853 bytes, checksum: 4e3a1c98a99f707552712a3e8c4868c5 (MD5) / Made available in DSpace on 2017-06-14T11:55:01Z (GMT). No. of bitstreams: 1 2015 - Victor Arantes Nunes.pdf: 1279853 bytes, checksum: 4e3a1c98a99f707552712a3e8c4868c5 (MD5) Previous issue date: 2015-07-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This work seeks to highlight the importance of teaching probability in high school subject in which teachers usually have some difficulty in transmitting content to their students. It highlighted the relevance of probability, given its broad scope, either in Statistics, Physics or Engineering. A literature review, which approached the historical side of gambling and have also discussed the theoretical aspects of basic probability, essential for good understanding of the content was performed. Then analyzed thoroughly federal lotteries, as well as its characteristics, basic rules and odds of winning in each of them. Finally, this paper suggests a teaching methodology based on lotteries, with different educational activities, in order to motivate and facilitate the understanding of high school students and encourage teachers, escaping the traditional way of teaching / Esse trabalho procura destacar a import?ncia do ensino de Probabilidade no Ensino M?dio, assunto no qual geralmente os professores tem certa dificuldade em transmitir o conte?do aos seus alunos. ? destacada a relev?ncia da Probabilidade, dado seu vasto campo de aplica??o, seja na Estat?stica, F?sica ou na Engenharia. Foi realizada uma revis?o bibliogr?fica, onde abordou-se o lado hist?rico dos jogos de azar e tamb?m foram discutidos os aspectos te?ricos da probabilidade b?sica, essencial para a boa compreens?o do conte?do. Em seguida, analisou-se minuciosamente as loterias federais, assim como suas caracter?sticas, regras b?sicas e probabilidades de se vencer em cada uma delas. Por fim, o presente trabalho sugere uma metodologia de ensino baseada nos jogos lot?ricos, com atividades pedag?gicas diferenciadas, com o objetivo de motivar e facilitar o entendimento dos alunos do Ensino M?dio, bem como estimular os docentes, fugindo da forma tradicional de se lecionar
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Estudo do desempenho de aplica??es da mec?nica dos s?lidos em computa??o paralela / Study of the performance of solid mechanics applications in parallel computing

Pinho, Ronilson Rodrigues 06 October 2014 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-19T12:18:08Z No. of bitstreams: 1 2014 - Ronilson Rodrigues Pinho.pdf: 623700 bytes, checksum: 7bc5eefc4b9dab2877f833cbdab95b9f (MD5) / Made available in DSpace on 2017-06-19T12:18:08Z (GMT). No. of bitstreams: 1 2014 - Ronilson Rodrigues Pinho.pdf: 623700 bytes, checksum: 7bc5eefc4b9dab2877f833cbdab95b9f (MD5) Previous issue date: 2014-10-06 / The Boundary Element Method (BEM) is a computational method for differential equations solutions, formulated in the form of integral domains. Thus, it is applied in Fluid Mechanics, Acoustics, Electromagnetics and Fractures study. The BEM requires discretization only regarding boundary geometry of the problem, but not inside as a whole, reducing the computational effort. In order to reduce computational effort, parallel computing is an efficient form of information processing emphasizing concurrent events exploitation during software execution. This processing status arises primarily due to high computational performance requirements and difficulty in increasing single processor core speed. Despite central processing units (CPUs), whether multiprocessors or multicore processors, are easily found today, several algorithms are not suitable to run on parallel architectures yet. The present study aimed to develop parallelism research, acting in a sequential program, using Fortran 77 language (VERA-TUDELLA, 2003), making numerical analysis of stress and strain 2D specific problems) of Solids Mechanics with BEM, as well as, its clamped and tensioned bar physical representation. This application implementation is intended to exploit the maximum parallelism / O M?todo de Elementos de Contorno (MEC) ? um m?todo computacional para a solu??o de sistemas de equa??es diferenciais, formuladas em forma de integrais. Aplicado na Mec?nica dos fluidos, Ac?stica, Eletromagn?ticos, Estudo de fraturas etc. O MEC requer discretiza??o apenas no contorno da geometria do problema, mas n?o do seu interior como um todo, diminuindo o esfor?o computacional. Com o intuito em diminuir o esfor?o computacional, a Computa??o paralela ? uma forma eficiente de processamento de informa??o com ?nfase na explora??o de eventos simult?neos na execu??o de um software. Ele surge principalmente devido ?s elevadas exig?ncias de desempenho computacional e ? dificuldade em aumentar a velocidade de um ?nico n?cleo de processamento. Apesar das CPUs multiprocessadas, ou processadores multicore, serem facilmente encontrados atualmente, diversos algoritmos ainda n?o s?o adequados para executar em arquiteturas paralelas. O presente estudo objetivou-se com o intuito de prosseguir na pesquisa sobre paralelismo, atuando num programa sequencial, desenvolvido na linguagem Fortran 77 (VERA-TUDELA, 2003), que efetua an?lises num?ricas de problemas espec?ficos tens?o e deforma??o em 2D) da Mec?nica dos S?lidos via MEC com representa??o f?sica da barra engastada e tracionada. A implementa??o da aplica??o, visa explorar o m?ximo o paralelismo
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Estudo cin?tico da atividade anticolinester?sica de derivados ?- Carbol?nicos do produto natural harmana

Torres, Juliana Mariano 22 July 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-08-01T17:07:57Z No. of bitstreams: 1 2011 - Juliana Mariano Torres.pdf: 1156662 bytes, checksum: 6ae713d0002e13c804fc2eba73bd8f5b (MD5) / Made available in DSpace on 2016-08-01T17:07:57Z (GMT). No. of bitstreams: 1 2011 - Juliana Mariano Torres.pdf: 1156662 bytes, checksum: 6ae713d0002e13c804fc2eba73bd8f5b (MD5) Previous issue date: 2011-07-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq. / The increase in life expectancy is a worldwide occurrence that shows the relative success of public health politics, and Brazil is among the countries where people are living longer and in better physical health. But the increase in life expectancy has a negative effect: the appearance of degenerative diseases typical of old age, including several forms of dementia, like Alzheimer?s Disease (AD) that is certainly the most important. It is an irreversible and progressive disease characterized by neuronal deterioration that results in loss of cognitive functions such as memory, communication skills, judgment and reasoning. Donepezil, rivastigmine and galantamine are medicines used for the treatment of AD and act reversibly inhibiting the acetylcholinesterase (AChE). Evidences suggest that the enzyme butyrylcholinesterase (BChE), closely related to AChE, plays a significant role in AD because it is involved in neural functions such as cholinergic co-regulation and non-cholinergic neurotransmission. The aim of this research is to provide new substances with anticholinesterase action by using ?-carboline derivatives from the natural product harmane and carry out a kinetic study to determine the inhibition profile of the enzymes AChE e BChE, which could help in the discovery of new compounds which could be useful in the treatment of AD. Firstly, a screening was carried out with seven ?-carboline derivatives. In a second stage, a kinetic investigation, employing Ellman?s method, was run with these compounds and all of them presented high anticholinesterase action for both AChE and BChE. All seven derivatives presented a non-competitive reversible inhibition. / Torres, Juliana Mariano. ESTUDO CIN?TICO DA ATIVIDADE ANTICOLINESTER?SICA DE DERIVADOS -CARBOL?NICOS DO PRODUTO NATURAL HARMANA. 2011. Disserta??o (mestrado em Qu?mica Org?nica). Instituto de Ci?ncias Exatas, Departamento de Qu?mica, Universidade Federal Rural do Rio de Janeiro, Serop?dica, RJ, 2011. O aumento da expectativa de vida ? um fen?meno mundial que mostra o relativo sucesso de pol?ticas de sa?de p?blica, e o Brasil se inclui entre os pa?ses em que as pessoas est?o vivendo por mais tempo e em condi??es melhores de sa?de. No entanto, o aumento da expectativa de vida tem como efeito negativo o aparecimento de doen?as degenerativas, t?picas de idades mais avan?adas, incluindo-se as v?rias formas de dem?ncia e entre estas, a mais importante ?, sem d?vida, a Doen?a de Alzheimer (DA), patologia irrevers?vel e progressiva caracterizada pela deteriora??o neuronal que resulta em perda de fun??es cognitivas, tais como mem?ria, capacidade de comunica??o, julgamento e racioc?nio. Para o tratamento da DA s?o utilizados f?rmacos como o donepezil, galantamina e rivastigmina, os quais agem inibindo revers?velmente a acetilcolinesterase (AChE). Evid?ncias sugerem que a enzima butirilcolinesterase (BChE), intimamente relacionada com a AChE, tem um papel significante na DA, uma vez que est? envolvida em fun??es neurais tais como a corregula??o da neurotransmiss?o colin?rgica e n?o-colin?rgica. Esta pesquisa pretendeu estudar novas subst?ncias com a??o anticolinester?sica utilizando derivados -carbol?nicos do produto natural harmana, bem como fazer um estudo cin?tico a fim de descobrir qual o perfil de inibi??o das enzimas AChE e BChE, a fim de buscar novos compostos que poderiam ser ?teis no tratamento dos sintomas da DA. Desta forma, foi efetuada preliminarmente uma triagem com 7 derivados -carbol?nicos e posteriormente foi realizada uma investiga??o cin?tica com estes compostos, uma vez que, todos apresentaram alta a??o anticolinester?sica tanto para AChE quanto para BChE. A cin?tica enzim?tica foi estudada segundo o m?todo de Ellman. Contudo, observou-se que todos os 7 derivados apresentaram uma inibi??o revers?vel n?o competitiva.
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A matem?tica: ferramenta interdisplinar na constru??o da aprendizagem na educa??o agr?cola

Nascimento , Emerson do 03 November 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-08-26T13:15:04Z No. of bitstreams: 1 2010 - Emerson do Nascimento..pdf: 2090889 bytes, checksum: fb83cd3a1b27b42a9d8d80f206c93f8f (MD5) / Made available in DSpace on 2016-08-26T13:15:04Z (GMT). No. of bitstreams: 1 2010 - Emerson do Nascimento..pdf: 2090889 bytes, checksum: fb83cd3a1b27b42a9d8d80f206c93f8f (MD5) Previous issue date: 2011-11-03 / Instituto Federal Goiano - Campus Morrinhos / The study presented was developed within a qualitative approach, from the direct contact and interactive mathematics as a tool in building interdisciplinary student learning in the course of agricultural technician. The research began with an investigation and reflection of the relationship between formal mathematics and the student every day, so we could build an interdisciplinary educational proposal capable of arousing student interest in building significant knowledge of mathematics in technical education. To make possible the construction of this proposal were made questionnaire and direct observation of students, identifying possible grievances and aspirations within the teaching-learning process of mathematics contextualized in vocational education. The results were instrumental in building the planning and execution of activities involving mathematics, promoting and paying contextualization within the disciplines of agricultural mechanization, topography, irrigation and drainage and applied mathematics. We note that at the end of the process the student has achieved the expected learning, getting to interact with the mathematical techniques and discipline to their daily lives. / O estudo que apresentamos foi desenvolvido dentro de uma abordagem qualitativa, a partir do contato direto e interativo da matem?tica como ferramenta interdisciplinar na constru??o da aprendizagem do aluno no curso t?cnico agr?cola. A pesquisa iniciou com uma investiga??o e reflex?o da rela??o entre a matem?tica formal e o cotidiano do aluno, para que fosse poss?vel construir uma proposta pedag?gica interdisciplinar capaz de despertar o interesse do aluno em construir o conhecimento significativo da matem?tica na forma??o t?cnica. Para que fosse poss?vel a constru??o dessa proposta foram realizados question?rio e observa??o direta dos alunos, detectando poss?veis insatisfa??es e anseios dentro do processo ensino-aprendizagem da matem?tica contextualizada no ensino profissional. Os resultados obtidos foram fundamentais na constru??o do planejamento e execu??o das atividades que envolviam a matem?tica, promovendo a integraliza??o e contextualiza??o dentro das disciplinas de mecaniza??o agr?cola, topografia, irriga??o e drenagem e matem?tica aplicada. Observamos que no final do processo o aluno conseguiu atingir a aprendizagem esperada, conseguindo interagir a matem?tica com as disciplina t?cnicas e com o seu cotidiano

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