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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.
151

Magmatismo gran?tico na por??o central do dom?nio Rio Piranhas-Serid?, Prov?ncia Borborema: geologia e petrologia do Stock Flores (RN)

Souza, Viviane Oliveira de 29 April 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-03T19:37:12Z No. of bitstreams: 1 VivianeOliveiraDeSouza_DISSERT.pdf: 10963808 bytes, checksum: 12e9b4d4da9f06196592b134e29e774d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-05T21:26:38Z (GMT) No. of bitstreams: 1 VivianeOliveiraDeSouza_DISSERT.pdf: 10963808 bytes, checksum: 12e9b4d4da9f06196592b134e29e774d (MD5) / Made available in DSpace on 2017-01-05T21:26:38Z (GMT). No. of bitstreams: 1 VivianeOliveiraDeSouza_DISSERT.pdf: 10963808 bytes, checksum: 12e9b4d4da9f06196592b134e29e774d (MD5) Previous issue date: 2016-04-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A fase final da orogen?se Brasiliana / Pan-Africana, na Prov?ncia Borborema, NE do Brasil, ? caracterizada por um intenso magmatismo gran?tico, dentro desse contexto granitog?nico insere-se o stock gran?tico Flores. O presente trabalho tem como objetivo a caracteriza??o geol?gica, petrogr?fica, geoqu?mica e petrol?gica do stock Flores. Para a efetiva??o do trabalho foram realizadas etapas de campo, prepara??o e descri??o de sec??es delgadas bem como tratamento de amostras para an?lises qu?micas. O stock localiza-se pr?ximo a cidade de Afonso Bezerra, na por??o centro-norte do Rio Grande do Norte, geologicamente inserido no contexto do Dom?nio Rio Piranhas-Serid?, ocorre alongado na dire??o NW expondo uma ?rea aflorante de 8 km2 . Sua morfologia ? ressaltada por extensos pared?es constitu?dos por conjunto de matac?es, os quais comp?em as bordas do stock, destacando-o facilmente do relevo regional. ? intrusivo em rochas gn?issicas paleoproterozoicas, relacionadas ao Complexo Caic?, e augen gnaisses da su?te Po?o da Cruz (borda Noroeste). As rochas do stock Flores s?o monzogranitos equigranulares hololeucocr?ticos, sendo poss?vel distinguir duas f?cies no plut?o em fun??o de seus aspectos texturais: Flores Tipo I, composta por rochas equigranulares m?dia de colora??o rosada, caracterizada pelos matac?es; Flores Tipo II, com rochas equigranulares fina de colora??o acinzentada a rosada, exibindo relevo arrasado na por??o S/SE do stock. Localmente (na f?cies Tipo II) ocorrem enclaves de rochas dior?ticas exibindo fei??es de coexist?ncia de magmas (mixing e migling), al?m de enclaves do tipo schlieren elipsoidais, sendo estes interpretados como estruturas magm?ticas formadas por convec??o magm?tica atrav?s de plumas termais. Os monzogranitos exibem parag?nese essencial composta por quartzo, microclina e plagiocl?sio, que usualmente somam mais de 90% modal. Biotita ? o m?fico principal, ocorrendo ainda, titanita, allanita, apatita, zirc?o e opacos, e, como minerais tardios, fluorita, clorita, ep?doto granular, mica branca e carbonato, estes relacionados a flu?dos em est?gio subsolidus. As an?lises geoqu?micas evidenciam a natureza evolu?da das rochas do stock bem como sua afinidade alcalina. Altos teores em SiO2 (71,43 - 74,87%), Na2O+K2O (8,26- 9,08%), Al2O3 (12,99-13,93%), al?m do empobrecimento em MgO (<0,5%), CaO (?1,4%), Fe2O3 (<2,3%) e TiO2 (<0,4%) refletem o car?ter peraluminoso e leucocr?tico das rochas, ii corroborado pelos baixos teores de m?ficos (< 6%). Diferentes diagramas discriminantes de s?ries/associa??es magm?ticas atestam a afinidade alcalina das rochas do stock Flores, bem como sua analogia com granitos tipo-A. O espectro do diagrama de ERTs exibe um moderado grau de enriquecimento de ETRL em rela??o aos ETRP com raz?es LaN /YbN entre 4,59% - 30,85% e forte anomalia negativa de Eu, caracter?stico de rochas crustais e de granitos tipo-A. Finalmente diagramas geoqu?micos discriminantes de ambiente tect?nico sugerem que o stock Flores ? um plut?o de assinatura p?s-colisional. Tais dados s?o coerentes com a idade U-Pb 553?4 Ma encontrada para o Flores, o colocando dentro do contexto tardi a p?s-orog?nico da orog?nese Brasiliana / Pan-Africana, na Prov?ncia Borborema. / The final phase of Brasiliano/Pan-African orogeny in the Borborema Province, NE Brazil, is marked by widespread granitic magmatism, in which setting the Flores stock is included. The present study aims to characterize the geological, petrographic, geochemical and petrogenetic aspects of this pluton. In order to develop the investigation, field work, thin section preparation and description and sample treatment for chemical analysis were carried out. The stock is located near the city of Afonso Bezerra, central-north of Rio Grande do Norte state, geologically enclosed in the Rio Piranhas-Serid? Domain. The pluton is elongated in the NW direction and has an outcrop area about 8 km2. Its morphology is highlighted by long cliffs made up by sets of boulders, which compose the borders of the stock, clearly contrasting it from the regional topography. It intrudes the paleoproterozoic gneissic rocks related to the Caic? Complex and augen gneisses of the Po?o da Cruz suite (NW border). Rocks of the Flores stock are equigranular, hololeucocratic monzogranites, being possible to distinguish two facies, according to their textural aspects: Flores Type I, made up by monzogranite of medium texture and pink in color, characterized by the boulders; Flores Type II, with fine equigranular rocks, greyish to pinkish in color, exhibiting denudated relief in the S/SE portion of the stock. Locally in Type II facies, there are dioritic enclaves displaying features of magma coexistence (mixing and mingling), in addition to ellipsoidal schlieren enclaves, the latter being interpreted as magmatic structures formed by magmatic convection triggered by thermal plumes. The monzogranites exhibit essential paragenesis composed of quartz, K-feldspar and plagioclase, which usually add over 90% modal. Biotite is the main mafic mineral. Titanite, allanite, apatite, zircon and opaque minerals also occur. Fluorite, chlorite, granular epidote, white mica and carbonate appear as late minerals, which are related to fluids in subsolidus stage. Geochemical analyzes attest the evolved nature of the stock rocks as well as their alkaline affinity. High levels of SiO2 (71.43 to 74.87%), Na2O + K2O (8.26 to 9.08%) and Al2O3 (12.99 to 13.93%) and depletion of MgO (<0 5%), CaO (?1,4%), Fe2O3 (<2.3%) and TiO2 (<0.4%) witness the peraluminous and leucocratic character of the rocks, which is supported by low levels of mafic minerals (<6%). Distinct discriminant diagrams of magmatic series/associations confirm the alkaline affinity of rocks of the Flores stock and their analogy with A-type granites. The REE?s diagram spectrum exhibits moderate LREE enrichment relative to HREE, with LaN / YbN ratios between 4.59% and 30.85% and strong negative Eu anomaly, characteristic of crustal rocks and A-type granites. Geochemical discriminant diagrams of tectonic setting point out a post-collisional signature for the Flores stock. These data are consistent with U-Pb age of 553?4 Ma given by the Flores, inserting it within the tardi to post-orogenic context of the Brasiliana / Pan-African orogeny in the Borborema Province.
152

Centro antigo de Jo?o Pessoa: forma, uso e patrim?nio edificado

Silva, Eudes Raony 01 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-12T14:09:59Z No. of bitstreams: 1 EudesRaonySilva_DISSERT.pdf: 22550637 bytes, checksum: 69997dc71110c526cc8ccf199374bbce (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-17T12:21:29Z (GMT) No. of bitstreams: 1 EudesRaonySilva_DISSERT.pdf: 22550637 bytes, checksum: 69997dc71110c526cc8ccf199374bbce (MD5) / Made available in DSpace on 2017-01-17T12:21:29Z (GMT). No. of bitstreams: 1 EudesRaonySilva_DISSERT.pdf: 22550637 bytes, checksum: 69997dc71110c526cc8ccf199374bbce (MD5) Previous issue date: 2016-08-01 / As transforma??es urbanas que a cidade de Jo?o Pessoa (PB) sofreu ao longo dos s?culos trouxeram consigo uma s?rie de consequ?ncias para seu n?cleo inicial, universo de estudo desta pesquisa. Sua gradativa perda na relev?ncia econ?mica para outras zonas da cidade veio acompanhada do surgimento de algumas patologias urbanas, usualmente vistas em muitas ?reas centrais nas grandes cidades brasileiras: degrada??o e descaracteriza??o do patrim?nio edificado, im?veis vazios ou subutilizados, esvaziamento do uso residencial, sensa??o de inseguran?a, entre outros. Esta disserta??o apresenta uma an?lise dessa realidade no Centro Antigo de Jo?o Pessoa, zona delimitada pelo per?metro de tombamento rigoroso estipulado pelo IPHAEP ? Instituto do Patrim?nio Hist?rico e Art?stico do Estado da Para?ba. A partir da observa??o da morfologia urbana da cidade, do levantamento de usos e da conserva??o do patrim?nio edificado no per?metro estudado, a disserta??o investigou as poss?veis correla??es entre essas tr?s vari?veis, e diagnosticou, com isso, as incompatibilidades geradoras das patologias ali existentes. O estudo morfol?gico se fundamentou na teoria descritiva conhecida como Sintaxe Espacial, onde se busca observar analogias entre a forma urbana e as rela??es sociais ali existentes, assumindo a proposi??o de que ambas podem ser mutuamente influenciadas. / The city of Jo?o Pessoa (Para?ba, Brazil) underwent urban transformations over the centuries that brought with them a number of consequences for its initial core, which is the study universe of this research. Its gradual loss of economic relevance to other parts of the city was accompanied by the emergence of some urban problems, usually seen in many downtown areas in large Brazilian cities such as degradation and mischaracterization of the built heritage, empty or underutilized buildings, decline of residential use, feeling of insecurity, among others. This paper presents an analysis of this reality in Old Town Jo?o Pessoa, within the historic perimeter set by IPHAEP (Historical and Artistic Heritage Institute of the State of Para?ba). The aim of the thesis was to investigate the possible correlations among these three variables: observation of the city urban morphology, uses and conservation of the built heritage in the studied perimeter, thereby diagnosing the incompatibilities that generate the existing conditions - besides suggesting possible solutions. The morphological study was based on the descriptive theory known as Space Syntax, which seeks to observe analogies between urban form and its existing social relations, assuming the proposition that both can be mutually influenced.
153

Desgaste de um rotor de ferro fundido cinzento revestido com camada de metal duro ap?s 1.000 horas de bombeamento de vinhoto operando na condi??o de cavita??o

Augusto, Ant?nio Roberto 01 September 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-12T14:19:58Z No. of bitstreams: 1 AntonioRobertoAugusto_DISSERT.pdf: 15947966 bytes, checksum: 6137cc9dd87967a91d0ea2a7fd5913a0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-17T13:19:05Z (GMT) No. of bitstreams: 1 AntonioRobertoAugusto_DISSERT.pdf: 15947966 bytes, checksum: 6137cc9dd87967a91d0ea2a7fd5913a0 (MD5) / Made available in DSpace on 2017-01-17T13:19:05Z (GMT). No. of bitstreams: 1 AntonioRobertoAugusto_DISSERT.pdf: 15947966 bytes, checksum: 6137cc9dd87967a91d0ea2a7fd5913a0 (MD5) Previous issue date: 2014-09-01 / A lideran?a mundial brasileira na obten??o de etanol derivado da cana de a??car pode ser associada ? produ??o do vinhoto, em uma raz?o de 10 a 18 litros de vinhoto para cada litro de etanol produzido durante o processo de destila??o. Nos cultivos da cana-de-a??car, esse vinhoto tem sido aplicado como adubo org?nico, onde o seu bombeamento ? um elemento cr?tico dessa cadeia produtiva. O objetivo deste trabalho foi investigar os principais mecanismos de desgaste de um rotor e de partes de uma bomba centr?fuga ap?s bombear vinhoto tratado em reator (pH 7,3?0.5). Um filme de 300?75 ?m de metal duro ? base de carboneto de tungst?nio-cobalto (WC-Co) foi aplicado ao rotor de ferro fundido cinzento da bomba atrav?s da t?cnica de aspers?o t?rmica HVOF. Considerando-se os trinta anos de experi?ncia do autor no projeto de sistemas de bombeamento, uma bancada para o bombeamento de vinhoto a 27?2oC foi desenvolvida em Laborat?rio para um servi?o de 1.000 horas atrav?s de ensaios durante dez horas di?rias e cont?nuas de uma bomba modelo INI 32-125 operando sob condi??es de cavita??o, conforme o c?lculo de NPSH. Um sistema de recircula??o do vinhoto foi adotado e controlado por uma v?lvula de descarga empregada comumente em processos industriais. Ap?s os ensaios, tanto o rotor revestido pelo metal duro como algumas partes n?o revestidas da bomba apresentaram um desgaste severo por cavita??o-eros?o, enquanto partes do rotor onde os efeitos da cavita??o s?o menores, o revestimento apresentou um desgaste moderado. / The Brazilian capability concerning to the world's leading producer of sugarcane ethanol can be joined together the vinasse production, which inherent amount discharged by distilling is from 10 to18 liters of vinasse per liter of ethanol produced. This vinasse has been applied in sugar-cane crops as organic fertilizer, where its pumping process is a critical element in this string. The aim of this work was investigate the main wear mechanisms of an impeller and parts of a centrifugal pump after pumping vinasse treated in reactor (pH 8,3?0,7). A tungsten carbide-cobalt (WC10Co4%Cr) film based hard metal of 360?35?m ?m was applied on the grey cast iron pump impeller by HVOF thermal aspersion. Based on the 30 years of experience of the author in the design and mounting of pumping systems, a test rig was developed in Laboratory for 1,000 hours of pumping tests of vinasse at 27?2oC for a continuous service during 10 hours by day for a pump model 32-125, working under cavitation conditions through the calculation of Net Positive Suction Head (NPSH), A recirculating system of the vinasse was adopted and controlled by a discharge valve usually employed in the industrial processes. After the tests, both the coated rotor as the uncoated parts of the pump showed severe wear by cavitation-erosion, while parts of the rotor where the effects of cavitation are smaller, the coating showed a moderate wear.
154

Obten??o de comp?sito Al2O3 / W a partir da redu??o aluminot?rmica do Al + APT, com igni??o a plasma

Souza, Eraldo C?mara de 22 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-27T12:30:35Z No. of bitstreams: 1 EraldoCamaraDeSouza_TESE.pdf: 1960987 bytes, checksum: aaf762025bc316dd0b3bce3590afc7a7 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-30T14:17:00Z (GMT) No. of bitstreams: 1 EraldoCamaraDeSouza_TESE.pdf: 1960987 bytes, checksum: aaf762025bc316dd0b3bce3590afc7a7 (MD5) / Made available in DSpace on 2017-01-30T14:17:00Z (GMT). No. of bitstreams: 1 EraldoCamaraDeSouza_TESE.pdf: 1960987 bytes, checksum: aaf762025bc316dd0b3bce3590afc7a7 (MD5) Previous issue date: 2016-07-22 / Neste trabalho foram obtidos comp?sitos alumina - tungst?nio (Al2O3 ? W), a partir da rea??o aluminot?rmica dos p?s de paratungstato de am?nia (APT) e alum?nio, misturados e mo?dos em moinho de alta energia. O p? obtido na moagem foi inserido numa tocha de plasma, impulsionado por um jato de arg?nio, e ao interagir com o plasma, foi aquecido abruptamente at? a temperatura de igni??o do alum?nio, reagindo exot?rmicamente. O produto da rea??o foi depositado sobre um substrato met?lico confeccionado em lat?o. Foram analisadas a influ?ncia da varia??o do fluxo de igni??o/alimenta??o e das dist?ncias tocha - substrato. Alternativamente, foi acoplado ? tocha, um dispositivo de confinamento do jato de plasma para as dimens?es do substrato. Os comp?sitos foram caracterizados quanto ? composi??o, fases e distribui??o de fases. A caracteriza??o das fases foi obtida por difra??o de raios X, a an?lise morfol?gica, atrav?s de microscopia eletr?nica de varredura - MEV e a an?lise qu?mica, atrav?s de espectroscopia de energia dispersiva - EDS. Os comp?sitos obtidos com o fluxo de plasma confinado apresentaram maior percentual de redu??o em rela??o a quantidade de W obtido, principalmente, com o fluxo de alimenta??o/igni??o de 5,0 l/min e 40mm de dist?ncia tocha-substrato. / In this work composite alumina ? tungsten (Al2O3 ? W) was obtained from the aluminothermic reaction of ammonium paratungstate (APT) and aluminum powders, mixed and grounded in high-energy mill. So the powder obtained was inserted in a plasma torch feeder, driven by a flux of argon, and when interacted with the plasma, was abruptly heated to the aluminum ignition temperature, reacts exothermically. The product of this reaction was deposited on a brass substrate. The influence of variation ignition/powder feeding as well as the distance from torch until substrate were analysed. Alternatively a confinement device for the plasma jet was attached in order to adjust the substrate dimensions. Chemical composition, phases and phase distribution of these composite materials were characterized. The X ? ray diffraction was used to analyze the existent phases; the Scanning Electron Microscopy (SEM) was used to perform the morphological aspect of the powder; and finally the Energy Dispersive Spectroscopy (EDS) was used for analyzing the chemical composition. The composites obtained by using confined plasma flux showed greater percentage reduction from the amount of W mainly when the feed/injection flow of 5 l/min and 40 mm of distance away torch-substrate were set up.
155

Fotoluminesc?ncia sintoniz?vel de LaPO4:Eu3+/Tb3+ hierarquicamente nanoestruturados, sintetizados via rota do etileno glicol assistida por micro-ondas

Oliveira, Rosiv?nia Silva de 15 April 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-02T11:57:41Z No. of bitstreams: 1 RosivaniaSilvaDeOliveira_DISSERT.pdf: 2954896 bytes, checksum: d9524f4e838d64f94b6283e655206857 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-06T20:43:09Z (GMT) No. of bitstreams: 1 RosivaniaSilvaDeOliveira_DISSERT.pdf: 2954896 bytes, checksum: d9524f4e838d64f94b6283e655206857 (MD5) / Made available in DSpace on 2017-02-06T20:43:09Z (GMT). No. of bitstreams: 1 RosivaniaSilvaDeOliveira_DISSERT.pdf: 2954896 bytes, checksum: d9524f4e838d64f94b6283e655206857 (MD5) Previous issue date: 2016-04-15 / LaPO4:Eu3+/Tb3+ hierarquicamente nanoestruturados foram sintetizados por meio da atua??o combinada do aquecimento de micro-ondas e de um solvente bi-funcional (etileno glicol), que atua n?o somente como solvente, mas tamb?m como agente estabilizante. Foram preparadas cinco amostras com diferentes concentra-??es de eur?pio e t?rbio ? La0.93Eu0.07PO4, La0.93Tb0.07PO4, La0.93Eu0.006Tb0.064PO4, La0.93Eu0.011Tb0.059PO4, La0.93Eu0.017Tb0.053PO4 ? bem como a matriz pura. Estas amostras, na forma de p?, foram caracterizadas por Difra??o de Raios-X (DRX), Es-pectroscopia de Infravermelho com Transformada de Fourier por Reflet?ncia Total Atenuada (FTIR-ATR), Microscopia Eletr?nica de Transmiss?o (MET) e Fotolumi-nesc?ncia (PL). Os resultados indicam cristaliza??o com estrutura do tipo monazita monocl?nica. Tamb?m sugerem uma organiza??o hier?rquica de agregados de na-nopart?culas formadas por cristais de semente. As amostras codopadas exibiram luminesc?ncia azul autoativada da matriz hospedeira, assim como emiss?es verme-lha e verde oriundas os ?ons Eu3+ e Tb3+, respectivamente. A an?lise espectrosc?pi-ca sugere que a transfer?ncia de energia entre os ?ons ocorre do t?rbio para o eur?-pio, mas o inverso n?o foi observado. Al?m disso, a varia??o da concentra??o relati-va destes ?ons permitiu o controle de cor das emiss?es. Desta forma, podemos afir-mar que a rota sint?tica escolhida ? eficiente na prepara??o de nanomateriais com propriedades ?pticas avan?adas e potencial para aplica??es em fot?nica, sensoria-mento e biorotulagem. / Hierarchically Nanostructured LaPO4:Eu3+/Tb3+ powders were synthesized by the combined action of microwave heating and a bifunctional solvent (ethylene gly-col), which act as both, solvent and capping agent. Five samples were prepared with different amounts of europium and terbium - La0.93Eu0.07PO4, La0.93Tb0.07PO4, La0.93Eu0.006Tb0.064PO4, La0.93Eu0.011Tb0.059PO4, La0.93Eu0.017Tb0.053PO4 - and the pure matrix. These samples, in powder form, were characterized by X-ray Diffraction (XRD), Attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR), Transmission Electron Microscopy (TEM) and Photoluminescence (PL). The results indicate the crystallization structure of the monoclinic monazite type. Also suggests a hierarchical organization of nanoparticle aggregates formed by seed crys-tals. The co-doped samples exhibited self-activated blue luminescence of the host matrix, as well as red and green emissions from Eu3+ and Tb3+ions, respectively. The spectroscopic analysis suggests that the transfer of energy between the ions occurs from terbium to europium, but the opposite was not observed. Moreover, the variation of the relative concentration of these ions enabled the tuning emissions. Thus, we can say that the chosen synthetic route is efficient in the preparation of nanomateri-als with advanced optical properties and potential applications in photonics, sensing, and biolabeling.
156

S?ntese de ze?litas a partir de um res?duo s?lico-aluminoso gerado na extra??o do l?tio do espodum?nio

Oliveira, Manuela Silva Martins de 05 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-20T21:21:26Z No. of bitstreams: 1 ManuelaSilvaMartinsDeOliveira_DISSERT.pdf: 4629063 bytes, checksum: 9e9e1aef7dcd4aa2529d87a665e32ac6 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-23T20:56:18Z (GMT) No. of bitstreams: 1 ManuelaSilvaMartinsDeOliveira_DISSERT.pdf: 4629063 bytes, checksum: 9e9e1aef7dcd4aa2529d87a665e32ac6 (MD5) / Made available in DSpace on 2017-02-23T20:56:18Z (GMT). No. of bitstreams: 1 ManuelaSilvaMartinsDeOliveira_DISSERT.pdf: 4629063 bytes, checksum: 9e9e1aef7dcd4aa2529d87a665e32ac6 (MD5) Previous issue date: 2016-08-05 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O l?tio ? um dos elementos que apresentam um elevado interesse comercial, justamente devido as suas caracter?sticas que possibilitam a utiliza??o em baterias de ?on l?tio, medicamentos, ligas, dentre outras aplica??es. Sua diversificada aplicabilidade aliada ?s dificuldades de obten??o faz com que esse material tenha um alto valor comercial. Um dos principais minerais de onde pode-se extrair l?tio ? o Espodum?nio. Industrialmente, o principal processo de obten??o do l?tio do espodum?nio ? a extra??o via ?cido sulf?rico. Tal processo gera como subproduto uma grande quantidade de res?duo s?lico-aluminoso que n?o possui destino final, sendo em sua maioria armazenados em aterros ou deixados ao ar livre. Foram estudados neste trabalho, diferentes procedimentos de s?ntese buscando diferentes estruturas zeol?ticas como uma maneira de agregar valor a este res?duo industrial. Seguiu-se como base a receita tradicional de cada estrutura fornecida pela ?International Zeolite Association? (IZA) modificando-a com a adi??o do res?duo s?lico-aluminoso. Os materiais sintetizados foram caracterizados atrav?s de difra??o de raios-X e microscopia eletr?nica de varredura (MEV). Foi poss?vel sintetizar ze?litas MER, EDI e MOR com alta cristalinidade e fase ?nica, sendo a primeira vez em que estas estruturas s?o obtidas atrav?s do res?duo s?lico-aluminoso proveniente da extra??o do l?tio do mineral espodum?nio. Outros materiais, tais como ze?lita LTA, foram obtidos, mas com pouca cristalinidade ou com mais de uma fase presente. Estudos complementares de otimiza??o desta s?ntese se fazem necess?rios. / Lithium is one of the elements that have a high commercial interest, precisely because of its features that allow use in lithium ion batteries, medicines, alloys, among other applications. Its diverse applicability allied to obtain difficulties makes this material has a high commercial value. One of the major minerals which can extract lithium is spodumene. Industrially, the main process of obtaining the spodumene lithium is extracted via sulfuric acid. This process generates as a byproduct a lot of silico-aluminous waste that has no final destination, being mostly stored in landfills or left outdoors. They were studied in this work, different synthetic procedures seeking different zeolite structures as a way to add value to this industrial waste. This was followed based on the traditional recipe of each structure provided by the "International Zeolite Association" (IZA) modifying it with the addition of silica-alumina residue. The synthesized materials were characterized by X-ray diffraction and scanning electron microscopy (SEM). It was possible to synthesize zeolites MER, EDI and MOR with high crystallinity and single phase, the first being that these structures are obtained by silico-aluminous waste from the extraction of the mineral spodumene lithium. Other materials, such as LTA zeolite, were obtained, but with low crystallinity or with more than one phase present. Further optimization studies are needed.
157

Miss?es Franciscanas como ferramenta da conquista dos sert?es de Pernambuco (1659-1763)

Rocha, Vanessa Anelise Figueiredo da 06 October 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-20T23:56:41Z No. of bitstreams: 1 VanessaAneliseFigueiredoDaRocha_DISSERT.pdf: 3286424 bytes, checksum: 24c0719656054c5257c138e248604c82 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-03T20:01:00Z (GMT) No. of bitstreams: 1 VanessaAneliseFigueiredoDaRocha_DISSERT.pdf: 3286424 bytes, checksum: 24c0719656054c5257c138e248604c82 (MD5) / Made available in DSpace on 2017-03-03T20:01:01Z (GMT). No. of bitstreams: 1 VanessaAneliseFigueiredoDaRocha_DISSERT.pdf: 3286424 bytes, checksum: 24c0719656054c5257c138e248604c82 (MD5) Previous issue date: 2016-10-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Na conquista de novos territ?rios, Portugal contou com o apoio de institui??es, como a Igreja cat?lica, que legitimaram sua expans?o e consolidaram seu Imp?rio. Frades de v?rias ordens religiosas estiveram presentes nas entradas de coloniza??o, mediando o contato de culturas distintas, pacificando e dilatando regi?es fronteiri?as, atrav?s da atividade mission?ria. ? pensando na import?ncia da Igreja para a coloniza??o do Brasil que nossa pesquisa pretende estudar as miss?es de catequese ind?genas, em Pernambuco, administradas pela Ordem de S?o Francisco, objetivando compreender como esses religiosos contribu?ram para delimita??o espacial do territ?rio da dita capitania. Nosso recorte temporal est? compreendido entre 1659, quando foi fundada a Prov?ncia de Santo Ant?nio do Brasil, e 1763, per?odo em que as miss?es foram transformadas em vilas e os franciscanos perderam a jurisdi??o espiritual e temporal sobre os ?ndios. Faremos uso de uma gama de documentos, tendo como principal acervo o Arquivo Provincial Franciscano, que nos permite compreender as rela??es estabelecidas dentro e fora dos aldeamentos, os interesses que os circundaram e o m?todo mission?rio dos frades menores. / In the conquest of new territories, Portugal had the suport of institutions such as the Catholic Church, that legitimated its expansion and consolidate its empire. Friars from various religious orders were present in the colonization of entries, mediating the contact of different cultures, pacifying and dilating border regions, through missionary activity. It is thinking about the importance of the Church for the colonization of Brazil that our research aims to study the indigenous catechetical missions in Pernambuco, administered by the Order of St. Francis, in order to understand how these religious contributed to spatial delimitation of the territory of said captaincy. Our time frame is from 1659, when it was founded the Province of St. Anthony of Brazil, and in 1763, during which the missions were transformed into towns and the Franciscans lost their spiritual and temporal jurisdiction over the Indians. We will use a range of documents, the main collection the Provincial Archives Franciscan, which allows us to understand the relationships established within and outside the villages, the interests that circled and the missionary method of the Friars Minor.
158

Influ?ncia das condi??es meteorol?gicas na concentra??o de rad?nio em ?rea de caatinga e mata atl?ntica dunar / Influence of weather conditions in radon concentration in caatinga area and atlantic dune

Dantas, Vanessa de Almeida 31 August 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-09T23:04:25Z No. of bitstreams: 1 VanessaDeAlmeidaDantas_TESE.pdf: 3738312 bytes, checksum: de5a62b1338eeb90aff1798f2d02d2e7 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-14T00:07:59Z (GMT) No. of bitstreams: 1 VanessaDeAlmeidaDantas_TESE.pdf: 3738312 bytes, checksum: de5a62b1338eeb90aff1798f2d02d2e7 (MD5) / Made available in DSpace on 2017-03-14T00:07:59Z (GMT). No. of bitstreams: 1 VanessaDeAlmeidaDantas_TESE.pdf: 3738312 bytes, checksum: de5a62b1338eeb90aff1798f2d02d2e7 (MD5) Previous issue date: 2016-08-31 / O Rad?nio (Rn-222) ? um g?s nobre-radiativo, incolor, inodoro, ins?pido, denso (9,73 kg/m3) e altamente sol?vel na ?gua (solubilidade de 1,67x10-4 a 25?C e 1Atm) que, com exce??o do Di?xido de Carbono, ? o g?s com maior solubilidade na Atmosfera. Neste estudo foram analisadas a varia??o e correla??o das vari?veis meteorol?gicas com as emana??es de Rad?nio e ?ons atmosf?ricos em um ambiente de floresta equatorial e Caatinga do estado do Rio Grande do Norte, Brasil. Especificamente em biomas do Nordeste do Brasil (NEB) pouco se sabe sobre o comportamento Rn-222, no que diz respeito ? distribui??o nos diferentes n?veis da baixa troposfera, a exemplo da Mata Atl?ntica Dunar e Caatinga. Assim, o objetivo foi de investigar a rela??o entre vari?veis meteorol?gicas, as concentra??es atmosf?ricas de Rn-222 e ?ons atmosf?ricos para o per?odo caracterizado como seco e chuvoso, no munic?pio de Apod?-RN e Parnamirim-RN no per?odo seco, inseridos no bioma de Caatinga e Mata Atl?ntica Dunar Nordestina que abrange cerca de 800.000 Km2 e 19.427 km?, respectivamente. As medidas foram realizadas a 1,5 m do solo. Coletaram-se dados de temperatura do ar, umidade relativa, velocidade e dire??o do vento e press?o atmosf?rica bem como concentra??es de Rn-222 e de ?ons atmosf?ricos. Os resultados mostraram um padr?o bimodal no comportamento di?rio da concentra??o de Rn-222, nas primeiras horas da manh? observado em todos os dias. Comportamento semelhante foi observado para a concentra??o de ?ons entre 04:00 e 05:00 HL (Hor?rio Local) em Parnamirim. Em Apod?, o ciclo di?rio da concentra??o de Rn-222 mostrou um padr?o semelhante ao de Parnamirim, com um m?ximo principal de 29,38 Bq/m3 e 24,00 Bq/m3 durante a esta??o seca e chuvosa, respectivamente, em torno de 17:00 HL e um m?ximo secund?rio ?s 15:00 HL com 27,37 Bq/m3 (esta??o seca) e 19,00 Bq/m3 (esta??o chuvosa). Estes ciclos s?o consistentes com situa??es de uma atmosfera estaticamente neutra devido ? transi??o de per?odos de est?vel para regimes inst?veis (primeiro pico) e inst?veis para est?vel (segundo pico) de acordo com o n?mero de Richardson Bulk tamb?m observado neste estudo. Atrav?s do modelo de regress?o linear m?ltipla via an?lise de componentes principais as vari?veis meteorol?gicas que se mostraram mais correlacionadas com a concentra??o de Rn-222, com explica??o de 88% foram a umidade relativa, velocidade do vento e a radia??o solar global. / The Radon (Rn-222) is a radioactive noble-gas, colorless, odorless, tasteless, dense (9.73 kg / m3) and highly soluble in water (solubility 1,67x10-4 25 ? C and 1 atm) that, except for carbon dioxide is the gas with greater solubility in the atmosphere. This study analyzed the variation and correlation of meteorological variables with the emanations of Radon and atmospheric ions in a rainforest environment and Caatinga in the state of Rio Grande do Norte, Brazil. Specifically, in Northeast biomes of Brazil (NEB) little is known about the Rn-222 behavior in relation to the distribution in the different levels of the lower troposphere, such as the Atlantic Forest Dune and Caatinga. The objective was to investigate the relationship between meteorological variables, atmospheric concentrations of Rn-222 and atmospheric ions to the period characterized as dry and rainy in the municipality of Apodi-RN and Parnamirim-RN in the dry season, entered in the biome Caatinga and Northeast Atlantic Forest Dune which covers about 800,000 km2 and 19,427 square kilometers respectively. The measurements were taken at 1.5 m above the ground. Collected from the air temperature data, relative humidity, wind speed and direction, atmospheric pressure and Rn-222 and atmospheric ion concentrations. The results showed bimodal pattern in the daily behavior of the concentration of Rn-222, in the early morning hours observed in every day. Similar behavior was observed for the concentration of ions between 04:00 and 05:00 HL (Local Time) in Parnamirim. In Apodi, the daily cycle of concentration of Rn-222 showed a pattern similar to Parnamirim, with a maximum principal of 29.38 Bq / m3 and 24.00 Bq / m3 during the dry and rainy seasons, respectively, around 17:00 HL and a secondary maximum at 15:00 HL with 27.37 Bq / m3 (dry season) and 19.00 Bq / m3 (rainy season). These cycles are consistent with conditions of a statically neutral atmosphere due to the periods of transition from stable to unstable regimes (first peak) and unstable stable (second peak) according to the Richardson number Bulk also observed in this study. Through multiple linear regression model via principal component analysis the meteorological variables that were more correlated with the concentration of Rn-222, with 88% explanation were the relative humidity, wind speed and solar radiation.
159

Uma carrada de sonhos: do ba? do Ant?nio Francisco para a sala de aula EJEANA

Azev?do, Maria Isabel de Macedo 28 August 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-21T18:48:27Z No. of bitstreams: 1 MariaIsabelDeMacedoAzevedo_DISSERT.pdf: 1694905 bytes, checksum: 98304d460c3f1247af157b69d8a8618a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-28T00:27:10Z (GMT) No. of bitstreams: 1 MariaIsabelDeMacedoAzevedo_DISSERT.pdf: 1694905 bytes, checksum: 98304d460c3f1247af157b69d8a8618a (MD5) / Made available in DSpace on 2017-03-28T00:27:10Z (GMT). No. of bitstreams: 1 MariaIsabelDeMacedoAzevedo_DISSERT.pdf: 1694905 bytes, checksum: 98304d460c3f1247af157b69d8a8618a (MD5) Previous issue date: 2015-08-28 / A Presente disserta??o procura descrever o trabalho com cord?is em uma turma de EJA da Escola Estadual Tomaz de Ara?jo, situada em Acari-RN. A pesquisa foi realizada sob a luz de duas categorias: oralidade e escrita. Analisando as dificuldades observadas no tocante ao gosto pela leitura e escrita nessa modalidade de ensino, foi pensado em um projeto que pudesse minimizar essas barreiras. Elegemos, portanto, o cordel como g?nero ideal para atrair a aten??o dos alunos em raz?o de elementos como a rima, a musicalidade, a linguagem simples, temas pr?ximos da realidade dos alunos. O objeto de estudo da pesquisa foi a recep??o dos alunos aos cord?is de Ant?nio Francisco, dados o lirismo e encantamento observados nos cord?is desse poeta popular, prop?cio, portanto, para transmitir valores humanos essenciais ? vida moderna, visto que o capitalismo e a corrida desenfreada pelas possess?es materiais faz com que os valores ?ticos, sociais e humanos sejam menosprezados. O trabalho est? pautado quanto ? est?tica da recep??o em Jauss (1994) e Iser(1996); No tocante aos estudos da poesia nos detivemos nas teorias de Candido(1988);Pinheiro(2007);Mois?s(2007); Mois?s (2012) e Kirinus(2011); Quanto ?s orienta??es metodol?gicas referentes ao ensino lan?amos m?o de Freire(2014); Esclarin(2006) e da Proposta Curricular para a Educa??o de Jovens e Adultos(2002); Para refletirmos sobre a cultura popular e a literatura de cordel nos pautamos em Batista(1977); Abreu(2001) e Kunz(2001); Evidenciamos que a partir do trabalho com cord?is os alunos passaram a gostar de ler e melhoraram a escrita. / The present dissertation tries to describe the work with twine in a EJA class of Tomaz de Ara?jo State School, located in Acari-RN. The survey was conducted in the light of two categories: oral and written. Analyzing the difficulties observed regarding the taste for reading and writing this type of education was thought of a project that could minimize these barriers. Elected, so the line as an ideal genre to attract students' attention because of elements such as rhyme, musicality, simple language, themes coming from the reality of students. The research study object was the reception of students to strings of Antonio Francisco, given the lyricism and enchantment observed in twine that popular poet, suitable therefore to convey essential human values to modern life, since capitalism and unbridled race by material possessions makes the ethical, social and human values are looked down upon. The work is guided as to the aesthetics of reception Jauss (1994) and Iser (1996); With regard to poetry studies we stopped the theories of Candido (1988); Pinheiro (2007), Moses (2007); Moses (2012) and Kirinus (2011); As for the methodological guidelines for the teaching of hand launched Freire (2014); Esclar?n (2006) and the Curriculum Proposal for the Youth and Adult Education (2002); To reflect on popular culture and the string literature in we base on Batista (1977); Abreu (2001) and Kunz (2001); We showed that from the work with twine students began to enjoy reading and writing improved.
160

Estudo do efeito da alumina no sistema WC-Al2O3 via metalurgia do p?

Silva, Mariana Chianca L?cio da 16 February 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-04-03T19:34:53Z No. of bitstreams: 1 MarianaChiancaLucioDaSilva_DISSERT.pdf: 4659510 bytes, checksum: cbcbd1ce303a5a396ae5c3538766d017 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-04-04T23:23:59Z (GMT) No. of bitstreams: 1 MarianaChiancaLucioDaSilva_DISSERT.pdf: 4659510 bytes, checksum: cbcbd1ce303a5a396ae5c3538766d017 (MD5) / Made available in DSpace on 2017-04-04T23:23:59Z (GMT). No. of bitstreams: 1 MarianaChiancaLucioDaSilva_DISSERT.pdf: 4659510 bytes, checksum: cbcbd1ce303a5a396ae5c3538766d017 (MD5) Previous issue date: 2017-02-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O carbeto de tungst?nio (WC) ? amplamente conhecido por suas excelentes propriedades f?sicas e mec?nicas, por?m, apresenta limita??es de uso principalmente quando a propriedade de tenacidade ? solicitada e h? a necessidade de um material mais leve. Como alternativa para minimizar essa problem?tica, a proposta ? a produ??o de um material que alie as propriedades do WC com a alumina (Al2O3), diminuindo assim a sua densidade e promovendo o aumento da tenacidade a determinada temperatura. Assim, neste trabalho, estudou-se os efeitos do percentual da alumina e dos par?metros de processamento da metalurgia do p? na microestrutura do particulado e do sinterizado (WC-Al2O3). E, al?m disso, foram analisadas propriedades f?sicas e mec?nicas, particularmente a densidade e a microdureza, do produto buscando um material de ferramenta de corte alternativo. No estudo, adotou-se, respectivamente, a rota de produ??o de materiais particulados. Os p?s do sistema apresentaram as seguintes composi??es: WC com 5, 10 e 15%p. de Al2O3; que foram processados via moagem de alta energia (MAE), em moinho planet?rio durante, 1, 4 e 10 horas. A conforma??o dos p?s mo?dos foi realizada por prensagem uniaxial de matriz cil?ndrica de di?metro de 5 mm, e com a press?o de compacta??o de 400 MPa. A sinteriza??o foi realizada em forno resistivo via fase s?lida, sob atmosfera controlada (arg?nio), nas temperaturas de 1450?C e 1550?C, durante 1 hora, e com uma taxa de aquecimento de 10?C/min. As mat?rias-primas foram caracterizadas atrav?s dos ensaios de particulometria, difra??o de raio-X (DRX) e microscopia eletr?nica de varredura (MEV). As amostras mo?das e sinterizadas foram submetidas aos mesmos ensaios de caracteriza??o dos p?s iniciais. E, os ensaios de microdureza foram realizados com as amostras sinterizadas. Os resultados mostraram que a moagem de alta energia influenciou significativamente na redu??o da distribui??o de tamanho, entretanto, n?o houve dispers?o das fases constituintes do material. E, devido a sinteriza??o ou consolida??o parcial dos compactados a verde, os valores de microdureza foram baixos, resultante da heterogeneidade da microestrutura que apresentou aglomerados das fases (WC-WC e Al2O3 -Al2O3), e, tamb?m, uma alta porcentagem de poros. Contudo, a alumina influenciou no refinamento da microestrutura dos sinterizados. / Tungsten Carbide (WC) is best known for its excellent physical and mechanical properties. However, it has limitations, mainly when the tougher and lighter material is requested. An alternative to minimize these problems is a composite of WC and alumina (Al2O3) to reducing density and promoting toughness at certain temperatures. Thus, in this work, the effects of the different amount of alumina and powder metallurgy processing parameters on microstructure of particulate and sintered composite (WC-Al2O3) were studied and the mechanical properties, particularly the microhardness, of the product were analyzed to find an alternative cutting tool material. In the study, the particulate materials production route was applied. The powders of the system have the following compositions: WC with 5, 10 and 15wt% of Al2O3 processed by high energy milling in a planetary milling for 1, 4 and 10 hours. Compacting of mixed powders was done using a uniaxial press in a cylindrical die of 5 mm diameter under a pressure of 400 MPa. Solid phase sintering was performed in a resistance furnace at 1450 and 1550 ?C with 1 hour of holding time and heating rate of 10?C/min in argon atmosphere. The raw materials were characterized by particulometry, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The milled powders and sintered samples were subjected to the same tests and microhardness test was also done for sintered samples as well. The results showed that high energy milling met the targets for particle size and however, there was no dispersion of the constituent phases of the material. Due to the sintering or partial consolidation of the green compacts, the microhardness values were low, due to the heterogeneity of the microstructure that presented agglomerates of the phases (WC-WC and Al2O3 -Al2O3), and also a high percentage of pores. However, alumina influenced the sintering microstructure refinement.

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