999 resultados para CAMINHOS DE FERRO


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Liquidus isotherms and phase equilibria have been determined experimentally for a pseudo-ternary section of the form MnO-(CaO+MgO)-(SiO2+Al2O3) with a fixed Al-2,O-3,/SiO2, weight ratio of 0.17 and MgO/CaO weight ratio of 0.17 for temperatures in the range 1473-1673 K. The primary phase fields present for the section investigated include manganosite (Mn,Mg,Ca)O; dicalcium silicate alpha-2(Ca,Mg,Mn)O (.) SiO2; merwinite 3CaO(.) ((Mg,Mn)O.2SiO(2); wollastonite [(Ca,Mg,Mn)(OSiO2)-Si-.]; ;tephroite [2(Mn,Mg)O.SiO2]; rhodonite [(Mn,Mg)O. diopside [(CaO,MgO,MnO,Al2O3)(SiO2)-Si-.]; tridymite (SiO2), SiO2] and melilite [2CaO (.) (MgO,MnO,Al2O3).2(SiO2,Al2O3)]. The liquidus temperatures relevant to ferro-manganese and silico-manganese smelting slags have been determined. The liquiclus temperature is shown to be principally dependent on the modified basicity weight ratio (CaO+Mgo)/(SiO2+Al2O3) at low MnO concentrations, and dependent on the mole ratio (CaO+ MgO+MnO)/(SiO2+Al2O3) at higher MnO concentrations.

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Phase equilibria have been determined experimentally for pseudo-ternary sections of the form “MnO”- (CaO+MgO)-(SiO2+Al2O3) with a fixed Al2O3/SiO2 weight ratio of 0.17 and MgO/CaO weight ratios of 0.25 and 0.17 respectively for temperatures in the range 1473-1673 K. The primary phase fields present for the MgO/CaO weight ratio of 0.17 include manganosite (Mn,Mg,Ca)O; dicalcium silicate α-2(Ca,Mg,Mn)O·SiO2; merwinite 3CaO⋅(Mg,Mn)O⋅2SiO2; wollastonite [(Ca,Mg,Mn)O·SiO2]; diopside [(CaO,MgO,MnO,Al2O3)·SiO2]; tridymite (SiO2); tephroite [2(Mn,Mg)O·SiO2]; rhodonite [(Mn,Mg)O·SiO2] and melilite [2CaO·(MgO,MnO,Al2O3)·2(SiO2,Al2O3)]. For the section with MgO/CaO weight ratio of 0.25 the anorthite phase (CaO⋅Al2O3⋅2SiO2) is also present. The liquidus temperatures of ferro- and silico-manganese smelting slags have been determined. The liquidus temperatures at low MnO concentrations are shown to be principally dependent on the modified basicity weight ratio (CaO+MgO)/(SiO2+Al2O3).

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O presente trabalho teve como um de seus objetivos analisar a inserção e a expansão do metodismo em Belo Horizonte MG, na perspectiva da práxis pastoral da Igreja, no período de 1892 a 1930, a fim de demonstrar que esse grupo, que foi o primeiro de natureza protestante a chegar à capital de Minas Gerais, desenvolveu sua ação missionária, caracterizada pela educação e evangelização. Sua inserção se dá num contexto marcado pelos ideais de modernização, inspirados no liberalismo e positivismo, quando profundas transformações na esfera econômica, política, nas concepções urbanístico-arquitetônicas e nos aspectos socioculturais se processavam na sociedade brasileira, especialmente entre o rompimento com o passado colonial e o desejo de modernização identificado na mudança do Império para a República, alterando assim o jeito do Brasil ser nação e apontando novos caminhos de diversidade religiosa. Esse novo momento permitiu ao metodismo construir sua identidade missionária a partir da relação da Igreja com a cidade e a cultura. A pesquisa, ao realçar ênfases missionárias do metodismo histórico e brasileiro, objetiva também resgatar a identidade do metodismo à luz da realidade urbana, entendendo ser essencial para ressignificar a práxis missionária nos dias de hoje. As ênfases do metodismo nascente, tanto na Inglaterra como nos EUA, e brasileiro puderam ajudar a construir uma nova proposta de missão para as grandes metrópoles brasileiras como Belo Horizonte. A construção dessa nova proposta nos contextos urbanos passou pelo redimensionamento de ênfases do metodismo (santificação transformadora, espiritualidade relevante, vocação pública, comunidade solidária), contribuindo na construção de uma pastoral que seja relevante para o contexto urbano.

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Esta dissertação tem por objetivo investigar a existência demotivações de gênero para o trânsito religioso de pentecostais para a Igreja Metodista. Para tanto, o primeiro passo é demonstrar a incidência deste fluxo migratório. Em seguida levantar e analisar as motivações paraa migração deste grupo para uma igreja protestante história. Neste sentido, o primeiro capítulo aborda assuntos correlatos ao tema como a religião, a modernidade e o campo religioso brasileiro, porque é no mundo que os papéis de gênero são remodelados e emerge a transitoriedade humana em um contexto de pluralidade e sincretismo religioso ao qual pertecem o protestantismo histórico e o pentecostalismo. O segundo capítulo descreve as origens domovimento metodista, sua entrada no Brasil e na cidade de São Paulo,as bases doutrinárias e costumes, bem como delimita o campo de pesquisa nela inserido, encerra com caracterização do trânsito religioso,destaca dados estatísticos, dinâmicas, razões e consequências sobre este fenômeno,cruzando-os com dados da pesquisa de campo realizada na Igreja Metodista do Distrito Grande ABC. Por fim, o terceiro capítulo, traz a tona à discussão sobre a questão de gênero, apresenta conceitos, caracterização e sua relevância na religião e no trânsito religioso, encerra com a análise das motivações deste fluxo migratório de pentecostais para a Igreja Metodista sob a perspectiva de gênero.

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Esta pesquisa examina o discurso de um programa televisivo regional brasileiro de canal aberto para identificar qual é a linguagem utilizada na abordagem de assuntos de Ciência e Tecnologia. O corpus compõe-se de um recorte baseado nas exibições do ano de 2006 do programa televisivo Caminhos da Roça - criado e exibido desde 2002 pela EPTV Ribeirão (Empresas Pioneiras de Televisão) afiliada da Rede Globo em Ribeirão Preto/SP. A proposta foi analisar, em relação ao formato, à linguagem e aos conteúdos as matérias jornalísticas que tratam especificamente de assuntos de ciência e/ou tecnologia voltadas para o agronegócio e que tenham mostrado algum contato entre pesquisador e cidadão do campo. Este trabalho, de natureza qualitativa, empregou a metodologia de Análise de Discurso de linha Francesa (AD) e identificou C&T como um assunto bastante presente no Caminhos da Roça. Constatou-se ainda que, embora haja muita divulgação de C&T não há um padrão de aprofundamento desses assuntos e que a abordagem varia de edição para edição, além da ciência ser mostrada em forma de tecnologia que se aplica ao campo. A linguagem empregada pelo Caminhos da Roça para o tratamento de assuntos de Ciência e Tecnologia é, predominantemente clara e simplificada e o discurso mais encontrado se define como uma mescla entre o tecnológico, o informativo e o pedagógico.(AU)

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O estudo pretende debater a idéia de sujeito a partir do cruzamento das idéias de autonomia, autoria e autor-cidadão como eixo teórico para, a partir da abordagem multirreferencial, indagar sobre de que maneiras é possível contribuir para a formação de sujeitos autônomos considerando a prática em uma universidade privada confessional. O sujeito aqui é apresentado não na perspectiva de um corpo biológico e físico, mas como projeto, considerando a historicidade, sociabilidade e, também, a questão da psique do ser humano. O objetivo do trabalho é analisar a formação do sujeito tendo em vista a proposta pedagógica da UMESP UNIVERSIDADE METODISTA DE SÃO PAULO. Esta opção justifica-se essencialmente pelo fato da escola apresentar uma proposta educacional diferenciada, que visa a formação cidadã. Os conceitos de instituição e autonomia são de extrema relevância para analisar no contexto da pesquisa proposta as representações e as práticas legítimas, bem como a necessidade de ressignificação da idéia de cidadania, diante das exigências da vida contemporânea. Trata-se, portanto, de uma pesquisa qualitativa de cunho exploratório. Quanto aos procedimentos metodológicos foi realizada a observação participante e com a aplicação de um roteiro qualificado buscou-se ouvir alunos da comunidade acadêmica. Foi possível perceber claramente as intenções ligadas à confessionalidade retratadas no Projeto Pedagógico da UMESP. Quanto às intenções dos alunos, observou-se a preocupação com a formação profissional. Tendo em vista nosso entendimento a respeito do exercício da cidadania a partir da autonomia do sujeito, estendemos nosso olhar para todos os atores sociais envolvidos. Observamos que é possível realizar um trabalho em direção ao autorcidadão porque o aluno, em geral, está aberto a transformar-se. A questão é relacional. Tem a ver de fato com a maneira como o ensino acontece. Professores e alunos devem encontrar-se como sujeitos em permanente construção, implicados. A educação pode desenvolver pessoas críticas e autônomas, sujeitos autores de suas próprias vidas atuando de acordo com seus desejos e conscientes de suas reais necessidades e responsabilidades.(AU)

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The Hf isotope composition of seawater does not match that expected from dissolution of bulk continental crust. This mismatch is generally considered to be due to retention of unradiogenic Hf in resistant zircons during incomplete weathering of continental crust. During periods of intense glacial weathering, zircons should break down more efficiently, resulting in the release of highly unradiogenic Hf to the oceans. We test this hypothesis by comparing Nd and Hf isotope time series obtained from NW Atlantic ferromanganese crusts. Both isotope systems show a decrease associated with the onset of northern hemisphere glaciation. The observed changes display distinct trajectories in epsilon Nd- epsilon Hf space, which differ from previously reported arrays of bulk terrestrial material and seawater. Such patterns are consistent with the release of highly unradiogenic Hf from very old zircons, facilitated by enhanced mechanical weathering.

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In this work, composites were prepared using high energy mechanical milling from the precursors hydroxyapatite - HAp (Ca10(PO4)6(OH)2) and metallic iron ( -Fe ). The main goal here is to study composites in order to employ them in magnetic hyperthermia for cancer therapy. The produced samples were characterized by X-ray di raction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), magnetization curves as a function of applied eld (MxH), and nally measurements of magnetic hyperthermia. The XRD patterns of the milled samples HAp/Fe revealed only the presence of precursor materials. The SEM showed clusters with irregular shapes. The magnetization curves indicated typical cases of weak ferromagnetic behavior. For samples submitted to grinding and annealing, the identi ed phases were: HAp (Ca10(PO4)6(OH)2), hematite (Fe2O3) and Calcium Iron Phosphate (Ca9Fe(PO4)7). Analyzing the results of MxH, there was a reduction of the saturation magnetization, given that the Fe was incorporated into HAp. Hysteresis curves obtained at 300 K are characteristics of samples possessing over a phase. At 77 K, the behavior of the hysteresis curve is in uenced by the presence of hematite, which is antiferromagnetic. Already at T = 4.2 K, it is observed a weak ferromagnetic behavior. Furthermore, there is the e ect of exchange bias. Regarding the magnetic hyperthermia, the results of temperature measurements as a function of the alternating eld are promising for applications in magnetic hyperthermia and other biomedical applications.

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This work aims to understand how cloud computing contextualizes the IT government and decision agenda, in the light of the multiple streams model, considering the current status of public IT policies, the dynamics of the agenda setting for the area, the interface between the various institutions, and existing initiatives on the use of cloud computing in government. Therefore, a qualitative study was conducted through interviews with a group of policy makers and the other group consists of IT managers. As analysis technique, this work made use of content analysis and analysis of documents, with some results by word cloud. As regards the main results to overregulation to the area, usually scattered in various agencies of the federal government, which hinders the performance of the managers. Identified a lack of knowledge of standards, government programs, regulations and guidelines. Among these he highlighted a lack of understanding of the TI Maior Program, the lack of effectiveness of the National Broadband Plan in view of the respondents, as well as the influence of Internet Landmark as an element that can jam the advances in the use of computing cloud in the Brazilian government. Also noteworthy is the bureaucratization of the acquisition of goods to IT services, limited, in many cases, technological advances. Regarding the influence of the actors, it was not possible to identify the presence of a political entrepreneur, and it was noticed a lack of political force. Political flow was affected only by changes within the government. Fragmentation was a major factor for the theme of weakening the agenda formation. Information security was questioned by the respondents pointed out that the main limitation coupled with the lack of training of public servants. In terms of benefits, resource economy is highlighted, followed by improving efficiency. Finally, the discussion about cloud computing needs to advance within the public sphere, whereas the international experience is already far advanced, framing cloud computing as a responsible element for the improvement of processes, services and economy of public resources

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Environmental liabilities from accidents in the retail petroleum industry, especially in urban areas, have represented a serious problem whose impact reaches the underground, people's health and even economic losses with the remediation process. In U.S.A. are estimated hundreds of billions of dollars invested in soil remediation processes. The results of the reports and investigative reports of liabilities in fuel stations distributed in the urban area of Natal-RN were used to estimate the local scenario of contamination. This database has been possible to determine the main contaminants (BTEX, PAHs, TOC), affected neighborhoods and types of potentially more impacted soils. Experiments were carried out in order to reverse contamination of this scenario, where the soil type was a factor in the planning, because it influences directly on the effectiveness of remediation techniques studied: Oxidation by hydrogen peroxide and oxidation by sodium persulphate. These oxidants are activated forming free radicals (HO•-, SO4 •-, HO2 • , O2 •-, S2O8 -2, etc) responsible for to mineralize the hydrocarbons and other organic compounds (releasing O2 e CO2). In the activation process, the ferrous ions (II) and ferric (III) were studied as well as hydrogen peroxide activation technique with sodium persulfate, the latter being presented the best efficiency among all the study, when activated with Fe+3. In addition to defining the most efficient technique, the aim of this study was to evaluate the influence of different soils among oxidative techniques, characterizing the effect of the concentration of these oxidants and also the concentration of the catalysts. Exists in most scenarios evaluated the presence of intrinsic total iron soil matrix. The so-called latosols present microaggregates reddish indicating the presence of these reactive species like iron and clayey aspect. The kinetic study was conducted by experimental design and monitoring of the percentage of total carbon (SSM-5000A) in the solid and liquid phases, knowing that 82.4% of the diesel molecule is carbon. Yet organic carbon and pH of liquid samples were analyzed for technical, characterizing the influence of soil type and its operating condition. The Fenton-like technique H2O2 e Fe+2 presented satisfactory oxidation, including sandy soil, but well below the best result. The sodium persulphate only activated with temperature, even in the most favorable soil, did not provide good efficiency. The best technique in the study had the concentration profile with 2,2x10- 1mol.L-1 of Na2S2O8 activated with 6,53x10-1mol.L-1 of H2O2 and 2,5x10-2 Fe3+mol.L-1 which reduced in less than a day 96 contamination in red soil, initially with 66,667 mg of diesel per kg of clean soil

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Tailings dams are structures that aims to retain the solid waste and water from mining processes. Its analysis and planning begins with searching of location for deployment, step on which to bind all kinds of variables that directly or indirectly influence the work, such as geological, hydrological, tectonic, topographic, geotechnical, environmental, social characteristics, evaluation security risks, among others. Thus, this paper aims to present a study on the most appropriate and secure type of busbar to design a layout structure of iron ore tailings, taking into account all the above mentioned variables. The case study involves the assessment of sites for location of dams of tailings disposal beneficiation of iron mine to be built in Bonito, in the municipality of Jucurutu in Seridó Potiguar. For site selection among alternatives, various aspects of the current state of the art were considered, one that causes the least environmental impact, low cost investment, adding value to the product and especially the safety of the implanted structure mitigates the concern about induced earthquakes as a result of liquefaction wastes somatized by dams in the region, as the tilling of Mina Bonito is located practically in the hydraulic basin dam Armando Ribeiro in environmental protection (APA). The methodology compares induced by dams in the semiarid region with the characteristics of the waste disposal and sterile seismicity, taking into account the enhancement of liquefaction by the action of seismicity in the Mina Bonito region. With the fulcrum in the methodology, we indicated the best busbar type for disposal of tailings from iron ore or combination of them, to be designed and built in semiarid particularly for Mina Bonito. Also presents a number of possible uses for the tailings and in engineering activities, which may cause processing to the common good.

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The goal set for this work was to synthesize and to characterize new iron and copper complexes with the Schiff base 3-MeOsalen and ligands of biological relevance, whose formulas are [Fe(3-MeOsalen)NO2], [Fe(3-MeOsalen)(etil2-dtc)], [Fe(3-MeOsalen)NO] and Na[Cu(3-MeOsalen)NO2]. The compounds were characterized by vibrational spectroscopy in the infrared region (IV) and Electronic spectroscopy in the ultraviolet and visible region (Uv-Vis). From the analysis of infrared spectra, they proved to formation of precursor complexes, as evidenced by changes in the vibrationals frequencies ν(C=N) e ν(C-O) and the emergence of vibrationals modes metal-oxygen and metal-nitrogen. For nitro complexes of iron and copper were observed ν(NO2)ass around 1300 cm-1 e ν(NO2)sim in 1271 cm-1 , indicating that the coordination is done via the nitrogen atom. The complex spectrum [Fe(3-MeOsalen)(etil2-dtc)] exhibited two bands, the ν(C-NR2) in 1508 cm-1 e ν(C-S) in 997 cm-1 , the relevant vibrational modes of coordinating ligand in the bidentate form. For the complex [Fe(3-MeOsalen)NO] was observed a new intense band in 1670 cm-1 related to the ν(NO). With the electronic spectra, the formation of complexes was evidenced by shifts of bands intraligands transitions and the emergence of new bands such as LMCT (p Cl-  d* Fe3+) in [Fe(3-MeOsalen)Cl] and the d-d in [Cu(3-MeOsalen)H2O]. As for the [Fe(3-MeOsalen)NO2] has highlighted the absence of LMCT band present in the precursor complex as for the [Cu(3-MeOsalen)NO2] found that the displacement of the band hipsocrômico d-d on 28 nm. The electronic spectrum of [Fe(3-MeOsalen)(etil2-dtc)] presented LMCT band shifts and changes in intraligantes transitions. With regard to [Fe(3-MeOsalen)NO], revealed a more energetic transitions intraligands regions from the strong character π receiver NO and MLCT band of transition dπFe(II)π*(NO).

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This work describes the synthesis and aplication of homogeneous and heterogenized iron catalysts in the alkylation reaction of toluene with propene, empolying experimental design. The homogenous complex was obtained trough the synthesis of the organic ligand folowed by the complexation of the iron(II) chloride. As to the heterogenized complexes, first were synthetized the inorganic supports (SBA-15, MCM-41 and Al-MCM-41). Then, it was synthetized the ligand again, that through funcionalization with chloropropyltrimethoxysilane (CPTMS), was anchored on the support previously calcinated. To these anchored ligands, was complexed the iron(II) chloride, previously solubilizated in tetrahydrofuran (THF). The organic ligand characterization was accomplished trough nuclear magnetic resonance (NMR) and Infrared spectroscopy (IV). The supports were characterized with x-ray diffraction (DRX), texture analysis with nitrogen adsorption/desorption (before and after the anchoring), termogravimetric analysis (TG) and infrared (IV). The metalic content was quantified trough the atomic absorption spectrophotometry (AAS). The complexes were tested in catalytic reactions emolying ethylaluminium sesquichloride (EASC) as co-catalyst in steel reactor, under mecanic stirring. The reaction conditions ranged from 4 to 36 ◦C, with many aluminum/iron ratios. The catalysts were actives in homogeneous and heterogenized ways. The homogenous catalytic complex showed a maximum turnover frequency (TOF) of 8.63 ×103 · h −1 , while, in some conditions, the anchored complexes showed better results, with TOF of until 8.08 ×103 · h −1 . Aditionally, it was possible to determine an equation, to the homogenous catalyst, that describes the product quantity in function of reacional temperature and aluminum/iron ratio.