Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-06-07T14:26:09Z No. of bitstreams: 1 2015 - Tassia Torres Furtado.pdf: 14895763 bytes, checksum: 7d611b6398d83fa875abc58ca88acab3 (MD5) / Made available in DSpace on 2017-06-07T14:26:09Z (GMT). No. of bitstreams: 1 2015 - Tassia Torres Furtado.pdf: 14895763 bytes, checksum: 7d611b6398d83fa875abc58ca88acab3 (MD5) Previous issue date: 2015-02-27 / The ascomycete yeast C.guttulatus, has long been recognized as a component of the normal microflora of rabbits and other herbivores. More recently, a possible association between this yeast and gastro-intestinal illness in dogs has been reported by researchers in Europe, EUA, Japan and Brazil. The current study combined morpho-phenotypic and molecular (PCR-RFLP and nucleotide sequencing), methods to examine C.guttulatus cultures recovered from Brazilian rabbits (15 isolates) and dogs (7 isolates), with the objectives of developing a means for the differential identification of C. guttulatus and to improve existing knowledge of the biology of this organism. Microscopic and macroscopic examination of isolated colonies in combination with zymogram analysis (carbohydrate fermentation tests), was unable to provide a definitive identification for the suspect cultures. In silico restriction fragment length polymorphism (RFLP) analysis of virtual PCR amplicons (corresponding to the D1-D2 domain of the gene encoding 26S ribosomal RNA of C.guttulatus and other yeast species known to be associated with dogs), indicated that digestion with the restriction enzymes DdeI, HaeIII and MspI would allow the differential identification of C. guttulatus. In vitro restriction analysis of PCR amplicons confirmed the predictions of the in silico analysis and demonstrated that differential identification of C.guttulatus could be a made using only two enzymes (DdeI and MspI). Sequencing of D1-D2 amplicons demonstrated the presence of substantial nucleotide variation within the cultures examined and divided them into three groups, denominated sequence types (ST?s). Two of these groups were closely related to each other. The third sequence type showed extensive nucleotide variation and may represent a novel species or subspecies within the genus Cyniclomyces / A levedura, Cyniclomycesguttulatus ? um ascomiceto e tem sido reconhecida como um componente da microbiota natural de coelhos e outros herb?voros. Mais recentemente, uma poss?vel associa??o entre esta levedura e doen?as gastrintestinais em c?es tem sido relatada por pesquisadores na Europa, EUA, Jap?o e Brasil. O presente estudo combinou m?todos de an?lises morfol?gica e molecular (PCR-RFLP e sequenciamento de nucleot?deos), para examinar culturas de C. guttulatus recuperados de coelhos brasileiros (15 isolados) e c?es (7 isolados), com o objetivo de desenvolvimento de um m?todo para a identifica??o diferencial de C. guttulatus e melhorar o conhecimento existente sobre a biologia desse organismo. O exame microsc?pico e macrosc?pico das col?nias isoladas em combina??o com an?lise do zimograma (testes de fermenta??o de carboidratos), n?o foi capaz de fornecer uma identifica??o definitiva para as culturas suspeitas. As an?lises in silico de polimorfismo de comprimento de fragmentos de restri??o (RFLP) de produtos de PCR virtuais (correspondentes ao dom?nio D1/D2 do gene 26S RNA ribossomal de C.guttulatus e outras esp?cies de levedura conhecidas como associadas a c?es), indicou que a digest?o com a enzimas de restri??o Ddel, HaeIII e MspI permitiria a identifica??o diferencial de C. guttulatus. As an?lises das digest?es in vitro de produtos de PCR confirmaram as previs?es das an?lises in silico e demonstrou que a identifica??o diferencial de C.guttulatus poderia ser feita usando apenas duas enzimas (DdeI e MspI). O sequenciamento dos produtos de PCR do dom?nio D1/D2 demonstraram a presen?a de varia??es substanciais de nucleot?deos nas culturas analisadas e estas foram divididas em tr?s grupos, denominados de sequ?ncias tipos (ST's). Dois destes grupos estavam estreitamente relacionados uns aos outros. O terceiro tipo de sequ?ncia mostrou grande varia??o de nucleot?deos e pode representar uma nova esp?cie ou subesp?cie dentro do g?nero Cyniclomyces

Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-09-28T21:50:56Z No. of bitstreams: 1 Disserta??o_Jessica_Coelho_Valerianoatual.pdf: 1739335 bytes, checksum: 6ad29bd975f2995c8c9a68ceee755a5b (MD5) / Made available in DSpace on 2016-09-28T21:50:56Z (GMT). No. of bitstreams: 1 Disserta??o_Jessica_Coelho_Valerianoatual.pdf: 1739335 bytes, checksum: 6ad29bd975f2995c8c9a68ceee755a5b (MD5) Previous issue date: 2016-02-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Schinopsis brasiliensis Engl. and Pseudobombax simplicifolium A. Robins are species widely distributed in the Brazilian semiarid. The pressure on the genetic resources from Caatinga biome, mainly medicinal and for wood, caused by subsistence or commercial use, leads to reduce genetic variability of these species. Based on that, the cytogenetic and the tissue culture can support the characterization and propagation strategies of their populations. The research goals of this study were evaluate growth regulators and culture media effects on the establishment and in vitro micropropagation for the species, and the use of fluorochromes CMA3/DAPI in the cytogenetic characterization of P. simplicifolium. For P. simplicifolium it was evaluated different DKW ingredient concentration, added or not activated charcoal and different concentration of BAP and IBA on the establishment and in vitro multiplication of the species. For S. brasiliensis, it was evaluated the micropropagation media DKW and WPM (with different concentration of BAP and IBA) and the use of activated charcoal and polyvinylpyrrolidone to reduce the oxidation during establishment of in vitro cultivation of the species. In S. brasiliensis, the addition of BAP in the micropropagation media did not promote in vitro multiplication of the species. In P. simplicifolium, the results obtained for variables studied varied depending on the regulators concentrations and among genotypes. Concentrations above 4.92 and 6.64 ?M.L-1 AIB inhibited the multiplication in vitro in both species. The double staining CMA3/DAPI allowed the visualization of 2n = 84 chromosomes and different numbers of CMA+ blocks in the genotypes of P. simplicifolium. / As esp?cies Schinopsis brasiliensis Engl. e Pseudocombax simplicifolium A. Robins encontram-se amplamente distribu?das no semi?rido brasileiro. A press?o sobre os recursos gen?ticos do bioma caatinga, principalmente, medicinal e madeireiro, seja devido ao uso para subsist?ncia ou comercial, tem levado ? perda da variabilidade gen?tica destas esp?cies. Em vista a isto, a cultura de tecidos e a citogen?tica podem auxiliar nas estrat?gias de caracteriza??o e propaga??o de suas popula??es. O objetivo deste trabalho foi avaliar o efeito de reguladores de crescimento e meios de cultura no estabelecimento e multiplica??o in vitro das duas esp?cies, bem como o uso dos fluorocromos CMA3/DAPI na caracteriza??o citogen?tica do imbiru?u. Em P. simplicifolium, avaliou-se diferentes concentra??es dos sais DKW, acrescidos ou n?o com carv?o ativado e diferentes concentra??es de BAP e AIB no estabelecimento e multiplica??o da esp?cie. Em S. brasiliensis, avaliou-se os meios DKW e WPM e o uso do carv?o ativado e da polivinilpirrolidona na redu??o da oxida??o, e o efeito de diferentes concentra??es de BAP e AIB no meio WPM no estabelecimento do cultivo in vitro da esp?cie. Em S. brasiliensis, a adi??o de BAP ao meio de cultura n?o favoreceu a multiplica??o in vitro da esp?cie. Em P. simplicifolium as respostas para as vari?veis estudadas variaram em fun??o das concentra??es dos reguladores e entre os gen?tipos da esp?cie. Concentra??es acima de 4,92 e 6,64 ?M.L-1 de AIB inibiram a multiplica??o in vitro em ambas esp?cies. A dupla colora??o CMA3/DAPI permitiu a visualiza??o de 2n= 84 cromossomos e diferentes n?meros de blocos CMA+ nos gen?tipos estudados de P. simplicifolium.

Made available in DSpace on 2016-04-04T18:21:36Z (GMT). No. of bitstreams: 1 Jose Augusto Rodrigues.pdf: 11526293 bytes, checksum: 9937a97ae0051c2993fcb25544f85b16 (MD5) Previous issue date: 2006-12-18 / A presente pesquisa apresenta como objetivo o levantamento do patrim?nio arquitet?nico da cidade de Mococa. O texto apresenta alguns dados de pesquisa que t?m como principal ojetivo trazer a discuss?o da import?ncia de preservar o patrim?nio arquitet?nico no nordeste do estado de S?o Paulo. Como exemplo particular, apresenta-se a cidade de Mococa (SP), pertencente ao Circuito Paulista Caf? com Leite, a qual preserva exemplares arquitet?nicos de alta qualidade tanto em sua ?rea urbana como na ?rea rural.

Submitted by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-04-24T14:45:40Z No. of bitstreams: 1 KatianeDuarteFelixDissertacao2017.pdf: 1649203 bytes, checksum: a93de32b23bab298272b9a92cf5cb40f (MD5) / Approved for entry into archive by Sara Ribeiro (sara.ribeiro@ucb.br) on 2018-04-24T14:46:44Z (GMT) No. of bitstreams: 1 KatianeDuarteFelixDissertacao2017.pdf: 1649203 bytes, checksum: a93de32b23bab298272b9a92cf5cb40f (MD5) / Made available in DSpace on 2018-04-24T14:46:44Z (GMT). No. of bitstreams: 1 KatianeDuarteFelixDissertacao2017.pdf: 1649203 bytes, checksum: a93de32b23bab298272b9a92cf5cb40f (MD5) Previous issue date: 2017-12-11 / In an environment with constant and rapid changes and increasing competition, organizations need to identify ways to be able to face this competition. SESI carried out 67 panels of specialists that identified 1275 products, comparing to the SESI portfolio, it was verify that of this total, 36.4% (464) SESI did not offer, 21.5% (274) SESI offer, providing a reflection on the lack of notion of specialists regarding the SESI portfolio in Occupational Safety and Health and Health Promotion. This way, the institution can benefit by identifying means of using digital technologies and existing information within its institutions through the identification of elements understanding of the dynamics in the dissemination and development of services to meet the demands of Brazilian industries. It??s proposed to characterize a system for a new relationship between SESI and customers in the service offering, using the PDCA Cycle methodology associated with the Design Thinking approach and requirements engineering concepts with the purpose of improving demand-side service. / Com as constantes e r??pidas mudan??as no ambiente e uma concorr??ncia cada vez maior, as organiza????es necessitam identificar formas de conseguir enfrentar essa competi????o. O SESI realizou 67 pain??is de especialistas que identificaram 1275 produtos, comparando ao portf??lio do SESI, verificou-se que deste total, 36,4% (464) o SESI n??o oferta, 21,5% (274) o SESI oferta, proporcionando uma reflex??o quanto ?? falta de conhecimento dos especialistas quanto ao portf??lio do SESI em Seguran??a e Sa??de no Trabalho e Promo????o da Sa??de. Com isso, a institui????o pode beneficiar-se ao identificar meios de utilizar as tecnologias digitais e as informa????es existentes dentro das suas institui????es atrav??s da identifica????o de elementos de entendimento da din??mica na divulga????o e no desenvolvimento de servi??os para o atendimento das demandas das ind??strias brasileiras. Prop??e-se caracterizar um sistema para nova forma de relacionamento entre SESI e clientes na oferta de servi??os, utilizando a metodologia do Ciclo PDCA associado a abordagem do Design Thinking e conceitos da engenharia de requisitos com intuito de melhoria do atendimento a demanda.

Made available in DSpace on 2014-12-17T15:42:06Z (GMT). No. of bitstreams: 1 JoaoBAF_DISSERT.pdf: 2926590 bytes, checksum: 284a772c6dacfa2a7184d7f4569c6cab (MD5) Previous issue date: 2011-03-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Although there are many studies on urban dust contamination by heavy metals in developed countries, little attention has been paid to this type of study in developing countries, including Brazil. Therefore, a series of investigations were performed to provide signatures of heavy metals in urban dust and assess the potential sources in the city of Natal - RN-Brazil. The fraction of these sediments was studied to pass through a sieve of 63 micrometers. For the study analyzed two groups of samples, one collected in September 2009 at the end of the rainy season (9 samples) and one collected in January 2010 in the dry season (21 samples). So in all, thirty sediment samples were collected from the street. Then, in Fluorescence Spectrometry X-rays were determined major elements SiO2, Na2O, K2O, Al2O3, MgO, P2O5, Fe2O3, MnO, TiO2 and CaO, and trace Rb, Cr, Ni, Cu, Zn, Sr and Pb by an ICPOES was determined Zn, V, Na, K, Ni, Mn, Mg, P, Fe, Cr, Cu, Pb, Ba, Ca and Al from leaching HCl 0.5 mol L-1 . The results of the concentrations of elements show that the greater presence of these occurs in the dry season, except for Si which is higher in the rainy season. Analyses by geoaccumulation Index (IGEO) Enrichment Factor (EF), Contamination Factor (CF), analysis correlation and Hierarchical Cluster, confirm that Zn, Cu and Pb is anthropogenic character. Zinc may be derived from various sources related to motor vehicles or the road signs and street grids. The elements Na, K, Mg and Ca may be related to droplets suspended in air containing cations and anions present in seawater (salty), common in Christmas throughout the year, brought by winds SE-NW. The elements Na, Mg, Ca and K are the most abundant in seawater and were analyzed in this study. This indicates that the source of these additional elements detected by analyzing the contamination factor may be the very sea. Moreover, Ni, Fe, Cr and Ba can be either as a source of anthropogenic geog?nica. The source of Ca is different, because it comes in lime and paint (painting guides of buildings and streets) in construction materials, but may also be present in sediments in the fragments of shells or carbonate bioclasts common in the coastal area / Embora existam muitos estudos sobre a contamina??o de poeiras urbanas por metais pesados nos pa?ses desenvolvidos, pouca aten??o tem sido dada a este tipo de estudo nos pa?ses em desenvolvimento, incluindo o Brasil. Portanto, uma s?rie de investiga??es foram realizadas para fornecer assinaturas de metais pesados em poeiras urbanas e avaliar as fontes potenciais na cidade do Natal RN-Brasil. A fra??o estudada destes sedimentos foi a passante na peneira de 63 μm. Para o estudo foram analisados dois grupos de amostras, sendo um coletado no m?s de setembro de 2009 no final da esta??o chuvosa (9 amostras) e outro coletado no m?s de janeiro de 2010 no final da esta??o seca (21 amostras). Portanto ao todo, trinta amostras de sedimentos de rua foram coletadas. Em seguida, por Espectrometria de Fluoresc?ncia de raios X foram determinados os elementos maiores SiO2, Na2O, K2O, Al2O3, MgO, P2O5, Fe2O3, MnO, TiO2 e CaO e tra?os Rb, Cr, Ni, Cu, Zn, Sr e Pb. Pela t?cnica de ICP-OES foram determinados Zn, V, Na, K, Ni, Mn, Mg, P, Fe, Cr, Cu, Pb, Ca, Ba e Al a partir de lixivia??o a HCl 0,5 mol L-1. Os resultados das concentra??es dos elementos mostram que a maior presen?a desses ocorre na esta??o seca, com exce??o para o Si que ? maior na esta??o chuvosa. As an?lises por ?ndice de Geoacumula??o (IGeo), Fator de Enriquecimento (FE), Fator de Contamina??o (FC), an?lises de correla??o e agrupamentos, confirmam que Zn, Cu e Pb tem car?ter antropog?nico. O Zn pode ser proveniente de fontes diversas relacionados aos ve?culos automotores ou ?s placas de sinaliza??o e grades das ruas. Os elementos Na, K, Mg e Ca podem estar relacionados ?s got?culas de ar que cont?m em suspens?o os c?tions e ?nions presentes na ?gua do mar (maresia), comum em Natal durante todo o ano, trazida pelos ventos SE-NW. Os elementos Na, Mg, Ca e K s?o os mais abundantes na ?gua do mar e foram analisados no presente trabalho. Isto indica que a fonte adicional destes elementos detectada atrav?s da an?lise do fator de contamina??o pode ser a pr?pria maresia. Por outro lado, Ni, Fe, Cr e Ba podem ser tanto de origem antropog?nica como de origem geog?nica. A fonte do Ca ? diversa, pois este entra na cal e tintas (pintura de edifica??es e guias de ruas), nos materiais de constru??o civil, mas pode estar tamb?m presente nos sedimentos nos fragmentos de conchas ou bioclastos carbon?ticos comuns na ?rea litor?nea

Made available in DSpace on 2014-12-17T15:42:06Z (GMT). No. of bitstreams: 1 EllenKLM_DISSERT.pdf: 2963115 bytes, checksum: f31b2e203bf9ce3c07ef2636fa792275 (MD5) Previous issue date: 2012-09-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Most of the energy consumed worldwide comes from oil, coal and natural gas. These sources are limited and estimated to be exhausted in the future, therefore, the search for alternative sources of energy is paramount. Currently, there is considerable interest in making trade sustainable biodiesel, a fuel alternative to fossil fuels, due to its renewable nature and environmental benefits of its use in large scale. This trend has led the Brazilian government to establish a program (Probiodiesel) with the aim of introducing biodiesel into the national energy matrix, by addition of 5% biodiesel to conventional diesel in 2010 to foster not only the increase of renewable energy, but reduce imports of crude oil. This work evaluates different methods of extraction of oil Carthamus tinctorius L., their characterization by IR, 1H and 13C NMR, HPLC and TG and their use in the production of methyl ester (molar ratio of oil / alcohol 1:6, and NaOH catalyst). The physico-chemical parameters (acid value, density, viscosity, saponification index and surface tension) of oil and biodiesel were also described. The produced biodiesel had a yield of 93.65%, was characterized in relation to their physicochemical properties showing satisfactory results (density=875 kg/m3, viscosity = 6.22 mm2/s, AI = 0.01 mg (NaOH) /g) compared with the values established by the the National Agency Oil, Natural Gas and Biofuels / A maior parte da energia consumida no mundo prov?m do petr?leo, do carv?o e do g?s natural. Essas fontes s?o limitadas e com previs?o de esgotamento no futuro, portanto, a busca por fontes alternativas de energia ? de suma import?ncia. Atualmente, h? um consider?vel interesse em tornar sustent?vel o com?rcio do biodiesel, um combust?vel alternativo ao de origem f?ssil, em fun??o de sua natureza renov?vel e dos benef?cios ambientais de seu emprego em larga escala. Essa tend?ncia levou o governo brasileiro a estabelecer um programa (Probiodiesel) com o objetivo de introduzir o biodiesel na matriz energ?tica nacional, atrav?s da adi??o de 5% de biodiesel ao diesel convencional em 2010, de forma a incentivar n?o somente o aumento de fontes renov?veis de energia, mas reduzir as importa??es do ?leo bruto. O presente trabalho avalia diferentes m?todos de extra??es (Soxhlet, Ultrassom e Exaustiva) do ?leo de Carthamus tinctorius L., sua caracteriza??o por IV, RMN 1H e 13C, CLAE, TG e Estabilidade Oxidativa que na presen?a de antioxidante demonstrou ser bastante satisfat?rio e seu emprego na produ??o de ?ster met?lico (raz?o molar ?leo/?lcool; 1:6; NaOH como catalisador). Os par?metros fisico-qu?micos (?ndice de acidez, densidade, viscosidade, ?ndice de saponifica??o e tens?o superficial) do ?leo e biodiesel tamb?m est?o descritos. O biodiesel produzido que apresentou rendimento de 93,65%, foi caracterizado em rela??o as suas propriedades fisico-qu?micas apresentando resultados satisfat?rios (Densidade = 875 kg/m3; Viscosidade = 6,22 mm2/s; IA = 0,01 mg (NaOH)/g) quando comparados com os valores estabelecidos pela Ag?ncia Nacional do Petr?leo, G?s Natural e Biocombust?veis

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-10-17T17:35:44Z No. of bitstreams: 1 2016 - Ernane Tarcisio Martins Gomes.pdf: 1573845 bytes, checksum: 78069c6459bd2b6aba951ba371ae74fd (MD5) / Made available in DSpace on 2017-10-17T17:35:44Z (GMT). No. of bitstreams: 1 2016 - Ernane Tarcisio Martins Gomes.pdf: 1573845 bytes, checksum: 78069c6459bd2b6aba951ba371ae74fd (MD5) Previous issue date: 2016-08-17 / CNPq / Soil organic matter can be derived from the decomposition of animal or vegetable. Most commercial crops show photosynthetic mechanisms C3 and C4, which set different carbon isotopes C12 or C13. Through isotopic analysis can determine the origin and prevalence of type of carbon that make up the soil organic matter (SOM) in a given area. Depending on the chemical fractionation MOS can also be divided into fractions FAF, FAH and FHU, these fractions have specific characteristics depending on their origin training and ambient conditions. The objective of this study was to evaluate the influence of plant origin C3 or C4 in the formation of the chemical and molecular structure of humic substances extracted from four areas with different vegetation cover, but submitted to agroecological management. To investigate this influence were extracted humic substances (HS) of these soils, being held chemical fractionation and chemical characterization by NMR analysis, FTIR, quantification and ?13C e ?15N isotopes in the AH fraction, 13 C-CP / MAS NMR and elemental determination. From the results obtained from these analyzes it was concluded that the plant does not influence qualitative differences, but in quantitative between the chemical components of humic substances (HS), the type of photosynthetic cycle does not seem to be a determining factor in the formation and incorporation of the types of structures in HA, but rather the quantities of these structures and their humic organizational distribution. The chemometric theoretical analyzes indicate that the development and preservation of humic these soils may be possible in intensive management systems such as rotation upon application of exogenous sources of stabilized SH, as well as favoring the humidification process in less managed systems as pasture and SAF. In this study it was demonstrated by characterization and chemometrics applied to AH of an agro-ecological system, the current state of MOS in terms of stability and structural enrichment and being proposed possible avenues for recovery and preservation of SH in mineral soils that may contribute to the increase in conditions fertility and thus agricultural production. / A mat?ria org?nica do solo pode ser oriunda da decomposi??o de animais ou vegetais. A maioria das culturas comerciais apresentam mecanismos fotossint?ticos C3 ou C4, que fixam diferentes is?topos de carbono C12 ou C13. Atrav?s de an?lises isot?picas ? poss?vel determinar a origem e predomin?ncia do tipo de carbono que comp?em a mat?ria org?nica do solo (MOS) em determinada ?rea. Em fun??o do fracionamento qu?mico a MOS ainda pode ser dividida nas fra??es FAF, FAH e FHU, estas fra??es apresentam caracter?sticas especificas em fun??o da sua origem de forma??o e condi??es ambientes. O objetivo deste trabalho foi avaliar a influ?ncia da origem vegetal C3 ou C4 na forma??o da estrutura qu?mica e molecular das substancias h?micas extra?das de quatro ?reas com cobertura diferentes vegetais, por?m submetidas ao manejo agroecol?gico. Para averiguar esta influ?ncia foram extra?das as substancias h?micas (SH) destes solos, sendo realizado o fracionamento qu?mico e caracteriza??o qu?mica atrav?s de an?lises de RMN, FTIR, quantifica??o de is?topos ?13C e?15N na fra??o de AH, 13C-CP/MAS NMR e a determina??o elementar. A partir dos resultados obtidos a partir dessas an?lises foi poss?vel concluir que a origem vegetal n?o influencia em diferen?as qualitativas e sim em quantitativas entre os componentes qu?micos das substancias h?micas (SH), o tipo de ciclo fotossint?tico n?o parece ser um fator determinante na forma??o e incorpora??o dos tipos de estruturas nos AH, mas sim nas quantidades destas estruturas e na sua distribui??o organizacional h?mica. As an?lises te?ricas quimiom?tricas indicam que a incorpora??o e preserva??o de MO humificada nestes solos pode ser poss?vel em sistemas de manejo intensivo como a rota??o, mediante aplica??es de fontes ex?genas de SH estabilizada, assim como tamb?m o favorecimento dos processos de humifica??o em sistemas menos manejados como pastagem e SAF. Neste estudo foi comprovado mediante carateriza??o e quimiometria aplicadas aos AH de um sistema agroecol?gico, o estado atual da MOS em termos de estabilidade e enriquecimento estrutural e sendo propostas poss?veis vias para a recupera??o e preserva??o das SH em solos minerais que possam contribuir ao aumento das condi??es de fertilidade e consequentemente da produ??o agr?cola.

Made available in DSpace on 2014-12-17T14:07:04Z (GMT). No. of bitstreams: 1 ElialdoCS_TESE.pdf: 4625434 bytes, checksum: bec8d03e9004e11648c49c45f84ffe0f (MD5) Previous issue date: 2010-03-26 / Universidade Federal do Rio Grande do Norte / The dielectric porcelain is usually obtained by mixing various raw materials proportions and is used in the production of electronic equipment for various applications, from capacitors of high and low Power to insulators for low, medium, high and extra high voltage, which are used in distribution lines and transmission of electricity.This work was directed to the s tudy of technological properties of technic porcelain, made from raw materials extracted from pegmatites found in the regions of Serid? and the Alto Oeste of Rio Grande do Norte, which are made of kaolin, quartz and feldspar, abundant and high quality in these regions. The technic ceramics were obtained by mixing in appropriate levels, kaolin, feldspar, quartz and clay, the last item from a pottery in the city of Sao Gon?alo do Amarante, Rio Grande do Norte. During the development the following characterizations correlated to raw materials were made: laser particle sizing, x-ray diffraction, DTA and TG. The compositions studied were formed by uniaxial pressing at a pressure of 50 MPa and sintered at temperatures ranging from 1150 to 1350?C and levels (times) of sintering between 30, 60, 90 and 120 minutes. The characterization of the samples were taken from the analysis of weight loss, linear shrinkage, porosity, stoneware curve, bulk density, flexural strength of three points, SEM and X-ray diffraction, TMA, Dielectric and cross Resistivity. The studied materials can be employed in producing the objects used in electrical engineering such as: insulators for low, medium and high-voltage electrical systems, command devices, bushing insulation for transformers, power capacitors, spark plugs, receptacles for fluorescent and incandescent light bulbs and others / A porcelana diel?trica ? normalmente obtida atrav?s da mistura de diferentes mat?rias-primas, em propor??es adequadas, sendo utilizada na produ??o de equipamentos eletroeletr?nicos de diversas aplica??es, desde capacitores de alta e baixa pot?ncia, a isoladores para baixa, m?dia, alta e extra alta tens?o, que s?o utilizados em linhas de distribui??o e transmiss?o de energia el?trica. Neste trabalho, s?o estudadas as propriedades tecnol?gicas de uma porcelana diel?trica, formulada a partir de mat?rias-primas obtidas de pegmatitos encontrados nas regi?es do Serid? e do Alto Oeste do Rio Grande do Norte, sendo estas constitu?das de caulim, quartzo e feldspato, abundantes e de alta qualidade nestas regi?es, e de uma argila proveniente de uma cer?mica situada no munic?pio de S?o Gon?alo do Amarante, tamb?m no Estado do Rio Grande do Norte. As mat?rias-primas foram caracterizadas atrav?s de: granulometria a laser, difra??o de raios X, an?lise t?rmica diferencial e an?lise termogravim?trica. As amostras foram conformadas por prensagem uniaxial a uma press?o de 50 MPa, e sinterizadas ?s temperaturas de 1150, 1200, 1250, 1300 e 1350 ?C, com patamares de sinteriza??o de 30, 60, 90 e 120 minutos. Os ensaios tecnol?gicos realizados foram: an?lise da perda de massa, retra??o linear, porosidade, curva de gressifica??o, microscopia eletr?nica de varredura, difra??o de raios X, dilatometria, rigidez diel?trica, resistividade transversal e permissividade diel?trica. Os melhores valores de propriedades foram obtidos na temperatura de 1250 ?C, para as composi??es estudadas, n?o sofrendo varia??es significativas em seu comportamento com o tempo de sinteriza??o. Os materiais estudados podem ser empregados na obten??o de objetos usados em eletrot?cnica como por exemplo: isoladores de baixa, m?dia e alta-tens?o para redes el?tricas, dispositivos de comando, bucha de isolamento de transformador, capacitores de pot?ncia, vela de igni??o, recept?culos de l?mpadas incandescentes e fluorescentes e outros

Made available in DSpace on 2014-12-17T14:07:06Z (GMT). No. of bitstreams: 1 BrunoLSC_DISSERT.pdf: 3848053 bytes, checksum: 28828821b0f45645fb6dc741dc2505bf (MD5) Previous issue date: 2013-09-28 / One of the great challenges at present time related with the materials area concerns of products and processes for use in petroleum industry, more precisely related to the Pre-salt area. Progresses were reached in the last years allowing the drilling of the salt layer, with the time reduction for drilling and larger success at the end. For the oil wells companies the preponderant factor is the technology, however, in spite of the progress, a series of challenges is still susceptible to solutions and one of them refers to the slurries preparation for cementing in those areas. Inside of this context, this study had for objective to analyze the influence of the salts NaCl, KCl, CaSO4 and MgSO4 in strength and chemical structure of the hydrated products. As methodology, they were prepared and analyzed cement slurries with varied concentrations of these salts that are commonly found in the saline formations. The salts concentrations used in formulations of the slurries were of 5%, 15% and 30%. The slurries were formulated with specific weight of 15,8 lb / gal and the cement used was Class G. Strength tests were accomplished in samples cured by 24 hours and 28 days. Also were realized crystallographic characterization (XRD) and morphologic (SEM). In agreement with the presented results, it is observed that the largest resistance values are attributed to the slurries with concentration of 15%. There was reduction of the strength values of the slurries formulated with concentration of 30%. Through the characterization microstructural it was possible to note the salts influence in the main cement hydrated products / Um dos grandes desafios da atualidade relacionado com a ?rea de materiais diz respeito ? produ??o de produtos e processos para uso na ind?stria do petr?leo, mais precisamente relacionado ? ?rea do Pr?-sal. Avan?os foram alcan?ados nos ?ltimos anos permitindo a perfura??o da camada de sal, com a redu??o do tempo para perfura??o dos po?os e maior ?xito ao final da opera??o. Apesar dos avan?os, uma s?rie de desafios ainda ? pass?vel de solu??es e um deles refere-se ? prepara??o de pastas para a cimenta??o de po?os nessas zonas com camadas evapor?ticas. Dentro deste contexto, este estudo teve por objetivo analisar a influ?ncia dos sais NaCl, KCl, CaSO4 e MgSO4 no comportamento mec?nico e estrutura qu?mica dos produtos hidratados. Como metodologia, foram preparadas e analisadas pastas de cimento com concentra??es variadas destes sais que s?o comumente encontrados nas forma??es salinas do reservat?rio do Pr?-sal. As concentra??es dos sais empregadas nas formula??es das pastas foram de 5%, 15% e 30%. As pastas foram formuladas com peso espec?fico de 15,8 lb/gal e o cimento utilizado na prepara??o das pastas foi o do tipo Portland Classe G. Foram realizados ensaios de resist?ncia ? compress?o em corpos de prova curados por 24 horas e 28 dias. Tamb?m foram realizados ensaios de caracteriza??o cristalogr?fica (DRX) e morfol?gica (MEV). De acordo com os resultados apresentados, observa-se que os maiores valores de resist?ncia s?o atribu?dos ?s pastas com concentra??o de 15 % para todos os sais. Houve, tamb?m, redu??o dos valores de resist?ncia das pastas formuladas com concentra??o de 30 % para todos os sais. Atrav?s das an?lises de caracteriza??o micro estrutural foi poss?vel observar a influ?ncia dos sais nos principais produtos hidratados do cimento Portland

Made available in DSpace on 2015-03-13T17:08:15Z (GMT). No. of bitstreams: 1 MarciaGS_ ate_Cap4.pdf: 2549651 bytes, checksum: 6eb717ac0ed84f3e72d899abd57a073f (MD5) Previous issue date: 1999-08-24 / Petr?leo Brasileiro SA - PETROBRAS / This dissertation deals with the characterization, distribution and provenience of heavy minerals along the Piranhas-A?u River, from the City of Parelhas (Serid? River) to your mouth at the City of Macau-RN. Many heavy minerals species were recorded in this study: clinoamphibole, epidote (including zoisite), garnet, sillimanite, tourmaline, staurolite, andalusite, zircon, rutile, augite, ilmenite, hematite and magnetite. Major transparent minerals, those forming more than 5% of some assemblages, are hornblende, epidote, tourmaline, staurolite and zircon. Predominant opaque mineral is ilmenite. Six assemblages were identified along the river: (i) Garnet-hornblende-tourmaline with sillimanite, when cutting rocks of the Serid? Formation; (ii) Hornblende-garnet-zircon, when crossing rocks of the Caic? gnaisse-migmatitic Complex; (iii) Hornblende-zircon-epidote-staurolite, when draining rocks of the Jucurutu Formation; (iv) Hornblende-zircon-epidote, when cutting rocks of the A?u Formation; (v) Hornblende-zircon-staurolite, on the lowermost A?u River, when crossing limestones of the Janda?ra Formation and (vi) Zircon-tourmaline-staurolite in the A?u River mouth (Cenozoic rocks) where coastal process dominate. Mineral ratios that reflect differences in grain shape, density, and selective chemical decomposition were used in an attempt to isolate the effects of source and process as controls of mineral variability. Reworking of the sediments was regionally effective in selective sorting; the more equant minerals (e.g. epidote) and heavier minerals (e.g. opaques) had a higher probability of being selected for permanent deposition during reworking. The processes of selective decomposition stand out at the river mouth. A priori knowledge of provenance, associated with the assemblage distribution and effects of process were utilized to the interpretations, that points to the follow provenances: hornblende comes from micashists of the Serid? Formation, orthognaisses and amphibolites of the Caico Complex, paragnaisses and paranphibolites of the Jucurutu Formation and granites intrusions; epidote comes from paragnaisses and calciosilicatics of the Jucurutu Formation, granites intrusions (?-Npy3al/ca and ?-Npy3mz, gravels deposits and A?u Formation; Andalusite and staurolite come from the Serid? Formation; Sillimanite, tourmaline and garnet come from micashists of the Serid? Formation, as well as from quartzites of the Equador Formation; Zircon comes from Precambrian rocks (pink and prismatic zircon) and from sediments of several cycles (round zircon); Opaques come from all rocks cutted for the Piranhas-A?u River; Rutile comes from metamorphic rocks, in general; Augite comes from the Cear?-Mirim, Serra do Cu? and Macau volcanisms. The texture of gravels deposits reveals a sediment transport mechanisms by traction-current processes, together with a diagenetic clay matrix suggests a hot-humid environments for deposition. The presence of unstable heavy minerals assemblages, as well as pebbles of different composition and degrees of rounding and esfericity, indicate more than one source. The occurrence of calcio/alkaline granites suites, in areas closed to the gravel deposits, suggests that these intrusions are the main source of sediments. This could explain for instance, the significant amounts of epidote and presence of unstable heavy minerals (e.g. hornblende). The analyses of heavy minerals also show significante variability between the modern (Piranhas-A?u) and ancestral (A?u Formation) river sediments. In general, these variations reflect relatively higher unstable and lower stable heavy minerals contents of the modern Piranhas-A?u sediments. The absence of significant compositional differences probably reflects uniform weathering conditions / This dissertation deals with the characterization, distribution and provenience of heavy minerals along the Piranhas-A?u River, from the City of Parelhas (Serid? River) to your mouth at the City of Macau-RN. Many heavy minerals species were recorded in this study: clinoamphibole, epidote (including zoisite), garnet, sillimanite, tourmaline, staurolite, andalusite, zircon, rutile, augite, ilmenite, hematite and magnetite. Major transparent minerals, those forming more than 5% of some assemblages, are hornblende, epidote, tourmaline, staurolite and zircon. Predominant opaque mineral is ilmenite. Six assemblages were identified along the river: (i) Garnet-hornblende-tourmaline with sillimanite, when cutting rocks of the Serid? Formation; (ii) Hornblende-garnet-zircon, when crossing rocks of the Caic? gnaisse-migmatitic Complex; (iii) Hornblende-zircon-epidote-staurolite, when draining rocks of the Jucurutu Formation; (iv) Hornblende-zircon-epidote, when cutting rocks of the A?u Formation; (v) Hornblende-zircon-staurolite, on the lowermost A?u River, when crossing limestones of the Janda?ra Formation and (vi) Zircon-tourmaline-staurolite in the A?u River mouth (Cenozoic rocks) where coastal process dominate. Mineral ratios that reflect differences in grain shape, density, and selective chemical decomposition were used in an attempt to isolate the effects of source and process as controls of mineral variability. Reworking of the sediments was regionally effective in selective sorting; the more equant minerals (e.g. epidote) and heavier minerals (e.g. opaques) had a higher probability of being selected for permanent deposition during reworking. The processes of selective decomposition stand out at the river mouth. A priori knowledge of provenance, associated with the assemblage distribution and effects of process were utilized to the interpretations, that points to the follow provenances: hornblende comes from micashists of the Serid? Formation, orthognaisses and amphibolites of the Caico Complex, paragnaisses and paranphibolites of the Jucurutu Formation and granites intrusions; epidote comes from paragnaisses and calciosilicatics of the Jucurutu Formation, granites intrusions (?-Npy3al/ca and ?-Npy3mz, gravels deposits and A?u Formation; Andalusite and staurolite come from the Serid? Formation; Sillimanite, tourmaline and garnet come from micashists of the Serid? Formation, as well as from quartzites of the Equador Formation; Zircon comes from Precambrian rocks (pink and prismatic zircon) and from sediments of several cycles (round zircon); Opaques come from all rocks cutted for the Piranhas-A?u River; Rutile comes from metamorphic rocks, in general; Augite comes from the Cear?-Mirim, Serra do Cu? and Macau volcanisms. The texture of gravels deposits reveals a sediment transport mechanisms by traction-current processes, together with a diagenetic clay matrix suggests a hot-humid environments for deposition. The presence of unstable heavy minerals assemblages, as well as pebbles of different composition and degrees of rounding and esfericity, indicate more than one source. The occurrence of calcio/alkaline granites suites, in areas closed to the gravel deposits, suggests that these intrusions are the main source of sediments. This could explain for instance, the significant amounts of epidote and presence of unstable heavy minerals (e.g. hornblende). The analyses of heavy minerals also show significante variability between the modern (Piranhas-A?u) and ancestral (A?u Formation) river sediments. In general, these variations reflect relatively higher unstable and lower stable heavy minerals contents of the modern Piranhas-A?u sediments. The absence of significant compositional differences probably reflects uniform weathering conditions