Geologia, mineralogia e química mineral do depósito intermediate sulfidation Santa Maria, Minas do Camaquã - RS

Discussões sobre classificação e contexto genético das mineralizações de metais base do distrito Minas do Camaquã são objeto de debate extenso na literatura. O distrito é composto por duas minas de cobre exauridas (Uruguai e São Luís) além de três depósitos de Pb-Zn, agrupados sob o nome de Jazida Santa Maria. O endownment combinado do distrito é de 513.4Kt Pb, 275,3Kt Zn, 193.7 Kt Cu, 883 t Ag e 4,5t Au. O presente trabalho foca na jazida de Pb-Zn-Cu-Ag (Au) Santa Maria, através de extenso levantamento de superfície e testemunhos de sondagem para mapeamento dos principais controles da mineralização, como alteração hidrotermal, estruturas e controles estratigráficos ou litológicos, além de detalhamento por estudos de petrografia, MEV e química mineral. Trabalhos prévios reportam forte componente magmático, com mistura de fluidos meteóricos para as mineralizações do distrito, tanto por isótopos como por inclusões fluidas, apesar da ausência de conexão obvia com magmatismo ou vulcanismo. As seqüências paragenéticas indicam estado de sulfetação intermediário com galena, esfalerita de baixo Fe e calcopirita, associadas à alteração filica que grada externamente para argílica intermediária, ambas afetadas por propilitização sutil nos estágios finais do processo mineralizante. As mineralizações IS epitermais estão encaixadas em rochas sedimentares siliciclásticas da bacia strike-slip Camaquã, de contexto pós-colisional, relacionada ao estágio de amalgamação do Gondwana. Uma perspectiva integrada do processo de mineralização em escala de distrito é proposta com base em resultados presentes e anteriores. Os fluidos hidrotermais compartilham trajetória evolutiva, com a geração de seqüências paragenéticas distintas devido a variações de T, fugacidade de H+ e S2 gás, entre a zona central representada pelas minas Uruguai e São Luís e a zona periférica do sistema epitermal representado pelo depósito Santa Maria. O estágio inicial de alteração hidrolítica gera um extenso halo argílico intermediário pervasivo no depósito de Santa Maria, com strike superior a 3 km, representado pela dissolução de limonita e calcita diagenéticas e também pela alteração moderada de feldspatos detríticos em ilita + Ca-Fe carbonatos + pirita. A ausência de cimentos diagenéticos e a conversão da associação detrítica em caulinita são relatadas nas minas de cobre e podem indicar a presença de halo argílico avançado no estágio precoce de alteração hidrotermal no centro do distrito. A zona argílica intermediária grada internamente para a zona filílica, representada por mineralização stockwork com disseminações restritas à vizinhança dos veios. No depósito Santa Maria a zona fílica é representada por muscovita + fengita + ilita + quartzo + apatita + carbonatos concomitantes à deposição de galena + esfalerita com baixo conteúdo de ferro e % FeS mol entre 0,12 e 1,2%. Calcita placóide ocorre comumente associada à mineralização venular. Nas minas de Uruguai e São Luís, o estágio fílico é inferido a partir da descrição de muscovita + quartzo + pirita, com predomínio de calcopirita como fase de sulfeto econômico. O estágio de mineralização principal do distrito ocorre em condições de estado de sulfetação intermediária. A presença de um estágio de migração da zona do cobre para a periferia do sistema é representada pela substituição de galena e esfalerita por calcopirita, e estas por bornita + pirita, com destruição parcial dos corpos de Pb-Zn na zona inferior da Santa Maria. Nas minas de cobre, os trabalhos prévios indicam que a calcopirita é substituída pela bornita, e esta por digenita e covelita. A migração da zona de cobre também indica flutuação no estado de sulfetação dos fluidos para alto e muito alto nas zonas externa e interna do distrito, respectivamente. Calcocita (+/- acantita) ocorre como última fase de mineralização de metais base, em substituição às fases de sulfeto anteriores em todos os corpos do distrito, e indica um retorno ao estado intermediário de sulfetação, próximo ao limite com o campo de baixa sulfeteção. A alteração propilítica acompanha parcialmente a etapa de migração da zona do cobre. O estágio propilítico é incipiente no JSM, marcado por clorita + pirita, além de veios de hematia +/- pirita (Au) e barita +/- carbonato que truncam todo o distrito, em distribuição mais ampla do que o envelope das mineralizações conhecidas. A sequência paragenética do depósito de Santa Maria em diagrama logƒS2 - 1000 / T, mimetiza a de depósitos IS de ambiente cálcio-alcalino conectados espacialmente às mineralizações do tipo Cu-porfírio, embora essa relação na região ainda não tenha sido encontrada. Os depósitos IS de ambientes pós-colisionais são escassos na literatura e recebem pouca atenção em estratégias de exploração mineral. O presente estudo pretende contribuir com o esforço recente de sistematização de informações sobre IS através de detalhamento geológico em um dos poucos exemplos mundiais desse tipo de depósito descrito no limite ediacarano-cambriano. O potencial para novas descobertas de depósitos IS na área permanece amplamente aberto, uma vez que o distrito aflora em uma janela estrutural da sequência não mineralizada do Grupo Guaritas, esta cobertura de uma vasta região sem exploração sistemática para mineralizações cegas. Adicionalmente, a possibilidade de conexão entre os depósitos epitermais das Minas do Camaquã e mineralizações tipo Cu-porfírio colisional permanece inconclusa.The genetic context and classification of Minas do Camaquã district, have been extensively discussed in the Brazilian literature since early 1900. The district consists of two exhausted copper mines named Uruguai and São Luís, in addition to three Pb- Zn deposits grouped as Santa Maria deposit. The combined endowment of the district is 513.4Kt Pb, 275.3Kt Zn, 193.7 Kt Cu, 883 t Ag and 4.5t Au. The following research brings novelty by approaching the Pb-Zn-Cu (Ag-Au) Santa Maria deposit geological framework, by means of an extensive drill core logging providing basis to acces in greater detail all rational trends controlling ore mineralization such as, hydrothermal alteration, stratigraphy, structural geology, petrography, minerology, mineral morphology (SEM) and mineral chemistry. Previous studies from isotopes and fluid inclusions revealed a strong magmatic signature of the hydrothermal fluids, and showed evidence of variable dilution degrees by meteoric fluids, despite the absence of any connection with intrusive or volcanic rocks. The sulfide paragenetic sequence corresponds to an intermediate sulfidation state, mainly composed by galena, low-Fe sphalerite and chalcopyrite. The ore zone is conformable to the hydrothermal halos, mostly within the phyllic zone, but partially overlapping the intermediate argillic zone. The hydrothermal zoning outward from phyllic to intermediate argillic zones, and both affected by a subtle propylitic alteration as a function of time. Ore bodies are hosted whithin siliciclastic sedimentary rocks from the ediacaran strike-slip Camaquã basin, of post-collisional setting related to Gondwana amalgamation. An integrated perspective of the mineralisation process at a district scale is proposed hereby, based in present and previous results. Although highly zoned, the ore fluids share evolutionary trajectory explained by the variations in T, fugacity of H+ and S2 gas, from the inner zone represented by Uruguai and São Luís mines, to the outer zone of the epithermal system represented by Santa Maria deposit. The early hydrolytic alteration stage generates an extensive pervasive intermediate argillic halo in the Santa Maria deposit striking over 3 Km in length. The alteration is represented by the dissolution of diagenetic limonite and calcite cements, and also by moderate alteration of detritic feldspar and plagioclase into illite + Ca-Fe carbonates + pyrite. The absence of diagenetic cements and the conversion of the detrital association to kaolinite; have been reported at the copper mines and may indicate an early advanced argillic halo. The intermediate argillic zone switch inwards to the phyllic zone, mainly stockwork with disseminations restricted by neighbouring veins. In Santa Maria it is represented by muscovite + phengite + illite + quartz + apatite + carbonates concomitant to the deposition of galena + sphalerite (low Fe), with % FeS mol from 0.12 to 1.2%. Platy calcite is often associated with the ore veins. According to previous work in the Uruguai and São Luís mines, the phyllic stage is composed by muscovite + quartz + pyrite, with a predominant mineralization of chalcopyrite. The main ore stage in the whole district is predominantly intermediate sulfidation state. An outwarding stage of the copper zone stage is indicated by galena and sphalerite replaced by chalcopyrite; and them both by Bornita+pyrite. There is a partial overprint of the Pb-Zn ore bodies in the lower zone of Santa Maria. In the copper mines, previous studies report chalcopyrite as the main ore stage, replaced by bornite, and these by digenite and covelite. The copper zone outwards, also indicates an increasing sulfidation state of fluids up to high and very high, in the outer and inner zones of the district respectivelly. Chalcocite (+/- acantite) is the last sulfide phase, and replaces all previous sulfides in the whole district ore bodies. It indicates a return to the intermediate sulfidation state, close to the low sulfidation state boundary. The copper zone outward is partially followed by propylitic alteration. The propylitic stage is incipient at Santa Maria, marked by chlorite + pyrite in addition to veins of hematite +/- pyrite (Au) and barite +/- carbonate. The integrated paragenetic sequence of the Santa Maria and the copper mines in a logƒS2 - 1000 / T diagram, mimics of the behavior observed in intermediate sulfidation deposits in calc-alkaline environment that are physically connected to Cu-porphyry type mineralizations. However, this relationship in the region has not been evidenced thus far. IS deposits in post-collisional settings, are scarse in the literature and may have been understimated for mineral exploration. The present study intends to contribute to recent efforts to summarize key features regarding IS-type deposits, through detailed geological description in one of the few known occurences reported from the ediacaran-cambrian boundary. The potential for new IS discoveries in the area remains largely unexplored, as the district outcrops in a structural window of Guaritas Group unmineralised sequence. The former covers a wide region, yet lacking systematic exploration for blind deposits. Furthermore, the possible link between the hereby presented deposit with a collisional Cu-porphyry, still remains an open question

Avaliação de tres metodos radiograficos - periapical, panoramico e sistema digital - no diagnostico de lesões apicais produzidas artificialmente

Orientador: Solange Maria AlmeidaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O presente estudo teve por finalidade avaliar três métodos radiográficos, radiografia periapical, radiografia panorâmica e sistema digital, no diagnóstico de lesões apicais produzidas artificialmente em mandíbulas maceradas. E se o tamanho das lesões interferem no diagnóstico radiográfico. Para tanto, as lesões apicais foram produzidas utilizando-se brocas esféricas com diâmetros diferentes, permitindo assim que o diâmetro das lesões sofresse alteração em tamanho conforme a broca utilizada. Assim, o estudo foi dividido em 04 fases: fase inicial ou 1, caracterizada pela ausência de lesão; fase 2, caracterizada pela lesão produzida com a broca 6 com medida da ponta ativa de 1,8mm; fase 3, caracterizada pela lesão produzida com a broca 8 com medida da ponta ativa de 2,3mm; fase 4, caracterizada pela lesão produzida com a broca 10 com medida da ponta ativa de 2,7mm; e fase cortical ou 5, quando a lesão atingia as corticais ósseas. Todas as fases foram, realizadas em 04 regiões da mandíbula: incisivo, canino, pré-molares e molares. As radiografias foram obtidas após cada fase e, posteriormente, foram analisadas por 04 radiologistas. Houve diferença estatisticamente significante na fase broca 6 (R) nos incisivos a favor do sistema digital. O mesmo ocorreu na fase cortical (LI) na região de pré-molares. Na região dos molares houve uma diferença etatisticamente significante na fase broca 10 (D) para a radiografia panorâmica e na fase cortical esta técnica foi a menos eficaz. Nas demais fases e regiões não houve uma diferença estatisticamente significanteAbstract: The aim of this study was to evaluate three radiographys techniques: periapical radiography, panoramic and digital radiography, about diagnostic accuracy of artificially produced bony lesions in human jaw dry. The periapical diseases were done using burs numbers 6, 8 and 10 thus allowing the lesions diameter to incresing according to burs size. Therefore, the study was dividided in four phases: phase 1 without periapical disease, phase 2 periapical disease made by bur number 6, phase 3 periapical disease made by bur number 8, phase 4 periapical disease made by bur number 10 and phase 5 periapical disease touchs junction area of the cortex. The phases were in four regions in the jaw, anterior, canine, premolar and molar. The radiographies were evaluated by four oral radiologists observers. The results showed that in the anterior region there was a significant statistically difference only at phase 2, that is the lesion was produced with bur 6, the digital radiography was more successfull and it was also observed in the premolar region in the cortical phase. In the molar region there was a false true result during the inicial phase, without lesion. During phase 4 (burn 10 ) and cortical phase there was a statistically significant difference in favor of the panoramic radiographyMestradoRadiologiaMestre em Odontologi

Projeto, análise e simulação computacional de um conversor cc-cc e cc-ca para alimentação de cargas ca a partir de uma máquina cc

Trabalho de Conclusão de Curso (Graduação)Atualmente o número de pessoas que tem gerado sua própria energia tem crescido cada vez mais com o uso de energias renováveis, principalmente por meios dos painéis fotovoltaicos que necessitam da radiação solar e dos aero geradores a partir da energia eólica. Pensando nisso, o objetivo principal deste trabalho é desenvolver um sistema off-grid, que através de uma força eletromotriz gerada por uma máquina CC, seja capaz de abastecer diretamente aparelhos que necessitam de energia elétrica, tais como bombeamento de água rural ou até mesmo para garantir a confiabilidade de consumidores que residem em locais remotos com difícil acesso a rede elétrica, sendo a solução mais econômica e prática de se obter energia

BIGhybrid - A Toolkit for Simulating MapReduce on Hybrid Infrastructures

Cloud computing has increasingly been used as a platform for running large business and data processing applications. Although clouds have become highly popular, when it comes to data processing, the cost of usage is not negligible. Conversely, Desktop Grids, have been used by a plethora of projects, taking advantage of the high number of resources provided for free by volunteers. Merging cloud computing and desktop grids into hybrid infrastructure can provide a feasible low-cost solution for big data analysis. Although frameworks like MapReduce have been conceived to exploit commodity hardware, their use on hybrid infrastructure poses some challenges due to large resource heterogeneity and high churn rate. This study introduces BIGhybrid a toolkit to simulate MapReduce on hybrid environments. The main goal is to provide a framework for developers and system designers to address the issues of hybrid MapReduce. In this paper, we describe the framework which simulates the assembly of two existing middleware: BitDew- MapReduce for Desktop Grids and Hadoop-BlobSeer for Cloud Computing. Experimental results included in this work demonstrate the feasibility of our approach

INITIAL L2C MULTIPATH AND NOISE PERFORMANCE ANALYSIS FROM REAL DATA

The modernization of the Global Positioning System has become already a reality with the launching of the first modern satellites. The new L2C signal has potential to provide additional information beyond the existing signals such as in environments with obstructions (urban areas, canyons, and forests). Obviously, questions arise. What is the evolution in terms of performance, user facilities and positional quality that this new signal will bring to civilian users? Will there be improvements over the old challenges experienced by the legacy signal, such as the ionospheric error and multipath? With the launch of the first satellites broadcasting the new L2C signal the possibility for an analysis of the behaviour of this signal under multipath and noise making use of actual observations became a reality. Multipath and noise double-difference residuals were extracted from L2C phase and code pseudorange, as well as from the existing C/A code in the L1 carrier for comparative analysis. The daily repeatability of these signals has been investigated aiming to extract and to separate the multipath and noise. Preliminary results confirm slightly smaller multipath values in the L2C signal

INITIAL L2C MULTIPATH AND NOISE PERFORMANCE ANALYSIS FROM REAL DATA

The modernization of the Global Positioning System has become already a reality with the launching of the first modern satellites. The new L2C signal has potential to provide additional information beyond the existing signals such as in environments with obstructions (urban areas, canyons, and forests). Obviously, questions arise. What is the evolution in terms of performance, user facilities and positional quality that this new signal will bring to civilian users? Will there be improvements over the old challenges experienced by the legacy signal, such as the ionospheric error and multipath? With the launch of the first satellites broadcasting the new L2C signal the possibility for an analysis of the behaviour of this signal under multipath and noise making use of actual observations became a reality. Multipath and noise double-difference residuals were extracted from L2C phase and code pseudorange, as well as from the existing C/A code in the L1 carrier for comparative analysis. The daily repeatability of these signals has been investigated aiming to extract and to separate the multipath and noise. Preliminary results confirm slightly smaller multipath values in the L2C signal

TECHNICAL AND ECONOMICAL FEASIBILITY ANALYSIS APPLIED TO HEALTH:: SCHOOL-CLINIC IMPLANTATION PROJECT

The importance of the school-clinic to psychology course is associated to teaching, researching and extension affairs in public universities in Brazil. Considering the actual context in Santo Antônio city, Bahia, in which is located the psychology course (Centro de Ciências da Saúde - Health Sciences Center - UFRB), it´s possible to realize that the institutions that actually assist mental health don´t have the necessary basic structure to the course´s academic needs. These limitations can make the clinical formation harder, restricting probation vacancies. The objective of the present study is to demonstrate the processes of economic and technical viability analysis applied in health. The used methodology was the study of economic and technical feasibility. The analysis object was the project of construction of a psychology school-clinic construction in the Universidad Federal do Recôncavo da Bahia (UFRB). These results can contribute to increase other feasibility studies of the health care area. The economy instruments usage for health care can reduce the failure of many public and private enterprises. Keywords: School-Clinic, Economic Feasibility, Saúde-Mental

A Review of Testbeds on SCADA Systems with Malware Analysis

Supervisory control and data acquisition (SCADA) systems are among the major types of Industrial Control Systems (ICS) and are responsible for monitoring and controlling essential infrastructures such as power generation, water treatment, and transportation. Very common and with high added-value, these systems have malware as one of their main threats, and due to their characteristics, it is practically impossible to test the security of a system without compromising it, requiring simulated test platforms to verify their cyber resilience. This review will discuss the most recent studies on ICS testbeds with a focus on cybersecurity and malware impact analysis