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Neue Technologien für hochzuverlässige Aufbau- und Verbindungstechniken leistungselektronischer BauteileBecker, Martin 03 November 2015 (has links) (PDF)
Achieving the utmost reliability of power semiconductors is an ongoing challenge for the scientists and engineers in the packaging community of the industry and research institutions. Still the semiconductor and therefore the function of the power module could live longer, when only the bonding and joining technologies would be more stable against power and temperature cycling wearout. In particular, the conventional electrical connection to the top and bottom surface of the semiconductor is limiting the lifetime due to degradation. For both, the solder layer under the backside and the Al-wire on the topside of the die, it is necessary to develop new contact technologies, as the substitution of just one connection does not perform the required reliability of the module.
In this work, different new technologies for power modules were evaluated and an own development is presented. Especially the new development is characterized by an outstanding reliability while keeping the design flexibility of the currently applied methods. To achieve that, the solder joints were replaced by Ag-sintered connections and Cu-wires were bonded as a substitute of Al-wires. This new approach is called DBB-Technology („Danfoss BondBuffer“) and is demonstrated in the example of a 1700V DBB power module.
With the help of this technology sintering creates two joints: One between the bottom of die and the substrate and between the die and a thin Cu-foil, which is located on top. This Cu foil (BondBuffer) enables the Cu-bond process as top contact technology without damaging the semiconductor. The DBB Cu foil acts as an absorber for the high bond-forces.
The detailed characterization of a DBB-covered semiconductor module reveals an extraordinary high reliability improvement, enhanced thermal impedance and upgraded electrical properties. / Leistungsmodule unterliegen in der Anwendung vielfältigen, kombinierten Beanspruchungen, die je nach Anwendung eine Herausforderung an unterschiedliche Verbindungsstellen im Modul darstellen.
Die Betriebsdauer eines Leistungsmoduls wird im Wesentlichen von den halbleiternahen Aufbau- und Verbindungstechniken limitiert. Das geht z.B. aus umfangreichen Lastwechseluntersuchungen hervor, in denen als Fehlermechanismen die Zerrüttung des Lots unter dem Chip oder das Abheben des Aluminium-Bonddrahts vom Halbleiter identifiziert wurden. Die einzelnen Verbindungsschichten im Leistungsmodul bilden eine Funktionskette, die beim Ausfall nur eines Gliedes die gesamte Funktionalität verliert. Maßnahmen zur Optimierung einzelner Schichten, z. B. der Halbleiter-Substrat-Verbindung oder nur der oberseitigen Chipkontaktierung, bringen alleinstehend also nicht den gewünschten Erfolg.
In dieser Arbeit werden unterschiedliche Aufbaukonzepte leistungselektronischer Module aus Fachveröffentlichungen verglichen, bevor das eigene Konzept beschrieben wird. Die Lösung basiert dabei auf innovativen und sehr robusten Fügetechnologien, die gezielt herkömmliche Verbindungen im Aufbau ersetzen. Das Ergebnis ist ein Leistungsmodul mit verbesserten thermischen, elektrischen und thermo-mechanischen Eigenschaften.
Eine wesentliche Rolle spielt dabei das Silbersintern als Alternative zum Löten. Dank der Sintertechnik geht der Halbleiter eine hochfeste Verbindung mit dem Substrat ein. Darüber hinaus ermöglicht die Sintertechnologie das stoffschlüssige Verbinden einer dünnen Kupferfolie mit der oberen Halbleitermetallisierung. Diese Kupferfolie ist erforderlich, um das Cu-Drahtbonden für die oberseitige Kontaktierung der Halbleiter anzuwenden, ohne diesen aufgrund hoher Bondkräfte zu zerstören. Dank der vorteilhaften Materialeigenschaften ist die Cu-Bondverbindung deutlich leistungsfähiger als eine Al-Bondverbindung.
Diese Kombination aus robusten Fügestellen trägt den Namen DBB-Technologie
(„Danfoss BondBuffer“) und soll zukünftig dank der Verfügbarkeit sinterbarer Halbleiter in hochzuverlässigen Leistungsmodulen angewendet werden.
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Refining of Silicon During its Solidification from a Cu-Si MeltVisnovec, Karl 03 January 2012 (has links)
Current methods of solar-grade silicon (SG-Si) production are energy intensive and costly. The possibility of using metallurgical techniques for refining metallurgical-grade Si (MG-Si) to SG-Si has been investigated. The main steps in the metallurgical refining route include alloying with copper to produce a 50-50wt% Cu-Si alloy, controlled solidification, crushing, and acid leaching. The controlled solidification process involved 5 variations to determine the best process to maximize Si dendrite agglomeration in the sample and produce the purest Si. This was determined by using various techniques, such as: optical imaging, dendrite analysis, EPMA and SEM analysis and ICP analysis. The crushing and acid leaching steps were carried out to remove the unwanted Cu3Si eutectic from the pure Si dendrite phase. Upon completion of the analysis techniques, the optimal cooling method was determined to be the top cooled, 0.5°C/min sample.
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Refining of Silicon During its Solidification from a Cu-Si MeltVisnovec, Karl 03 January 2012 (has links)
Current methods of solar-grade silicon (SG-Si) production are energy intensive and costly. The possibility of using metallurgical techniques for refining metallurgical-grade Si (MG-Si) to SG-Si has been investigated. The main steps in the metallurgical refining route include alloying with copper to produce a 50-50wt% Cu-Si alloy, controlled solidification, crushing, and acid leaching. The controlled solidification process involved 5 variations to determine the best process to maximize Si dendrite agglomeration in the sample and produce the purest Si. This was determined by using various techniques, such as: optical imaging, dendrite analysis, EPMA and SEM analysis and ICP analysis. The crushing and acid leaching steps were carried out to remove the unwanted Cu3Si eutectic from the pure Si dendrite phase. Upon completion of the analysis techniques, the optimal cooling method was determined to be the top cooled, 0.5°C/min sample.
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Sunkieji metalai (Fe, Pb, Cd, Cu) Saimaa ežero (Suomija) hidrosistemos atskirose litoralės zonose / Heavy metals (fe, pb, cd, cu) in separate littoral's zones in the saimaa (finland) lakeVadakojytė, Sandra 08 September 2009 (has links)
Mūsų gyvenamoji aplinka - gyvoji ir negyvoji gamta yra labai trapi ir pažeidžiama. Tarp daugelio cheminių teršalų ypatingą vietą užima sunkieji metalai. Jie pasižymi ilgalaikiu ir įvairiapusišku toksiniu poveikiu, keliančiu rimtą grėsmę gyvąjai gamtai ir žmonių sveikatai, o jų migracijos aplinkoje kasmet didėja. Medžiaga surinkta Saimos ežero pakrantėse, šalia urbanizacijos centų (Anttola, Astuvansalmi, Ristina, Imatra, Savonlinna, Orijärni, Mikkeli, Puumala) 2004 m. rudenį (spalio, lapkričio mėn.,) ir 2005 m. vasarą (birželio mėn.). Duomenys analizuoti naudojant Eric D. van Hullebusch 2004 m metodika – modifikuota A. Tessier metodika. Sunkiųjų metalų kiekiai nustatyti AAS ir voltimetru. Nustatyta, kad sunkieji metalai skirtinguose substratuose kaupiasi nevienodai, o didžiausias užterštumas jais teritorijose šalia trašų ir plieno fabrikų (Orijarni, Ristina) bei medžio apdirbimo įmonių (Anttola, Mikkeli). / Our living environment – the living nature and inanimate nature are extremely fragile and vulnerable. Among the various chemical pollutants the most prevalent are heavy metals. They are defined as the ones with permanent and various toxic effects, which endangers living nature and human health the most. The migration of this pollutant in the atmosphere is increasing every year. The samples were taken from the Saimaa lakeside near urban centres (Anttola, Astuvansalmi, Ristina, Imatra, Savonlinna, Orijärni, Mikkeli, Puumala ) in autumn 2004 (October, November) and summer 2005 (June). The materials were analyzed by using Eric D. van Hullebusch 2004 method – modified by A. Tessier methods. The quantity of heavy metals was measured by using a voltmeter and AAS. It was diagnosed that heavy metals are accumulating unevenly in the various substratum. And the biggest impurities were found in the territory around manufacturing of the chemical fertilizers and steel factories (Orijarni, Ristina), also wood processing factories(Anttola, Mikkeli).
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PARENTING INFLUENCING CHILD AND ADOLESCENT CU TRAITS : The Role of Parental Harshness and Parental Warmth in the Development of CallousUnemotional Traits in Children and Adolescents <18: A Systematic Review.Sandberg, Åsa Therese January 2014 (has links)
The present review sought to clarify and synthesise the existing research of the role parental harshness and parental warmth have on children and adolescents with callous unemotional traits by comparing research across different study designs and study samples in a systematic review. The systematic review search rendered in 16 publications which revealed that callous unemotional traits moderate the relationship between parental harshness as well as parental warmth and behaviour problems in children and adolescents. The moderation effect was directed by the level of callous unemotional trait in the child or adolescent where those with low levels exhibited the most negative effects when exposed to parental harshness. Conversely, children or adolescents with elevated levels exhibited the most positive effects when being exposed to parental warmth. Furthermore, the review revealed that both forms of parenting predict changes in callous unemotional traits over time, where parental harshness increased traits and parental warmth decreased traits. These results are further discussed in relation to the contextual theories of Lykken’s parental competence and socialisation model as well as Kochanska’s conceptual model of conscience development.
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Síntese e caracterização de complexos de Cu(I), Cu(II) E Au(I) com ligantes triazenidos contendo substituintes triazóis / Synthesis and characterization of Cu(I), Cu(II) AND Au(I) complexes with triazenido ligands containing triazole substituentsMorgan, Dieisson 29 November 2013 (has links)
Triazenido ions are isoelectronic to amidinato anions,[R'N C(R)=NR']- and have a broad versatility in coordination chemistry. Metal complexes including triazenido ligands find applications in various areas of chemistry. Triazenes and complexes including triazole derivatives show extensive applicability as for example in supramolecular chemistry and pharmacological compounds. This work presents deals with the study of new triazene derivatives with triazole substituents resulting from the click reactions, acting as ligands in complexes with Cu(I), Cu(II) and Au(I). The following ligands 1,3-bis(2-azidophenyl)triazene (2), 1-(methyl)-3-(2-(4-phenyl-1,2,3-triazole)triazene-N-oxide (4), 1-(phenyl)-3-(2-(4-phenyl-1,2,3-triazole)triazene (5), 1,3-bis(2-(4-phenyl-1,2,3-triazole)triazene (6) and, complexes 1,3-bis(2-azidophenyl)triazenide-κN11- triphenylphosphine-gold(I) (2a), bis-{1-(methyl)-3-[2-(4-phenyl-1,2,3-triazole-κN2)]triazenide-1-oxide-κ2N3,O}copper(II) (4b), 1-(phenyl)-3-(2-(4-phenyl-1,2,3-triazole)triazenide-κN- triphenylphosphine-κP-gold(I) (5a), 1,3-bis(2-(4-phenyl-1,2,3-triazole)triazenide-κN- triphenylphosphine-κP-gold(I) (6a), bis[1,3-bis(2-(4-phenyl-1,2,3-triazole-κN2)-μ-N3-triazenide]-κN11,κN13 copper(I)κN13,κN11´copper(I) (Cu Cu) (6b) were investigated. The compounds were characterized by IR, UV-Vis and NMR (1H e 13C) spectroscopy, low or high resolution mass spectrometry (EI, ESI, ESI(+)-TOF and ESI(-)-TOF) and X-ray diffraction on single crystal. Triazene (2) and complex (2a) exhibit intramolecular assembling through classical and non-classical hydrogen bonding. Complexes with Au(I), (2a), (5a) e (6a), the metal atom show linear coordination geometry. The metal atom in complex (6b) shows a T distorted coordination geometry, which is extended to a quadratic coordination resulting from d10 d10 interactions between Cu(I) ions. Triazene (6) and its respective complexes (6a) e (6b) exhibit intermolecular interactions of the type C−H···M. Antibacterial activity of triazene (5) and complex (5a) were assayed resulting to be inactive against the bacteria tested. / Os compostos triazenidos são isoeletrônicos a íons amidinatos [R'NH C(R)=NR'], e têm sido usados com sucesso na química de coordenação. A complexação a íons metálicos possibilita a sua aplicação em diversas áreas da química. Assim como os triazenos, os triazóis possuem vasta aplicabilidade, desde a química supramolecular até a área farmacológica. Este trabalho apresenta o estudo inédito de pré-ligantes triazenos contendo substituintes triazóis os quais foram obtidos a partir de reações de Click, e seus respectivos complexos de Cu(I), Cu(II) e Au(I). Foram sintetizados os pré-ligantes 1,3-bis(2-azidofenil)triazeno (2), 1-(metil)-3-(2-(4-fenil-1,2,3-triazol)triazeno-N-óxido (4), 1-(fenil)-3-(2-(4-fenil-1,2,3-triazol)triazeno (5), 1,3-bis(2-(4-fenil-1,2,3-triazol)triazeno (6) e os complexos 1,3-bis(2-azidofenil)triazenido-κN11-trifenilfosfina-ouro(I) (2a), bis-{1-(metil)-3-[2-(4-fenil-1,2,3-triazol-κN2)]triazenido-1-óxido-κ2N3,O}cobre(II) (4b), 1-(fenil)-3-(2-(4-fenil-1,2,3-triazol)triazenido-κN-trifenilfosfina-κP-ouro(I) (5a), 1,3-bis(2-(4-fenil-1,2,3-triazol)triazenido-κN-trifenilfosfina-κP-ouro(I) (6a), bis[1,3-bis(2-(4-fenil-1,2,3-triazol-κN2)-μ-N3-triazenido]-κN11,κN13 - cobre(I)κN13,κN11´cobre(I) (Cu Cu) (6b). Estes foram caracterizados por espectroscopia de IV, UV-Vis e RMN (1H e 13C), espectrometria de massas de baixa ou alta resolução (EI, ESI, ESI(+)-TOF e ESI(-)-TOF) e difração de raios X em monocristal. O triazeno (2) e complexo (2a) apresentam ligações de hidrogênio intermoleculares e intramoleculares do tipo clássica e não-clássica. Os complexos de Au(I), (2a), (5a) e (6a) possuem geometria de coordenação linear. O complexo (6b) apresenta uma geometria T distorcida, a qual é estendida para quadrática pela interação d10 d10 entre os átomos de Cu(I), o triazeno (6) e seus complexos (6a) e (6b) apresentam ainda ligações intermoleculares do tipo C−H···M. Foi testada a atividade antibacteriana do triazeno (5) e o complexo (5a), os quais mostraram-se inativos frente às bactérias testadas.
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Etude des mécanismes de formation de phases dans des films minces du système ternaire Al-Cu-FeHaidara, Fanta 21 July 2011 (has links)
Les mécanismes de formation de phases dans des films minces du système ternaire Al-Cu-Fe et des systèmes binaires Al-Cu, Al-Fe et Cu-Fe ont été étudiés. Dans chacun des systèmes, plusieurs échantillons avec des compositions distinctes ont été préparés par pulvérisation cathodique. Des couches d’aluminium, de cuivre et de fer ont été déposées séquentiellement sur des substrats de silicium oxydé et ont été traités thermiquement par différentes méthodes puis caractérisés. Des mesures de diffraction de rayons X et de résistivité in-situ ont été effectuées pour suivre la formation des phases. Des recuits thermiques suivis de trempe ont été réalisés et les échantillons ont été caractérisés par diffraction des rayons X. L’analyse enthalpique différentielle a également été utilisée ainsi que des mesures simultanées in-situ de résistivité et de diffraction des rayons X. L’ensemble des résultats obtenus nous a permis de proposer des mécanismes de formation de phases pour chacun des échantillons étudiés et en utilisant des modèles théoriques de croissance de phases nous avons pu déterminer des données cinétiques sur la formation de phases dans ces films. / The mechanisms of phase formation in thin films have been studied in the Al-Cu, Al-Fe, Fe-Cu and Al-Cu-Fe systems. Several samples with different compositions have been prepared by sputtering. Aluminium, copper and iron layers were deposited onto oxidized silicon substrates, they were heat treated and characterized by using several techniques. In situ X-ray diffraction and resistivity measurements were used to follow the phase formation. Thermal annealings followed by quenching have also been carried out to get additional information.Differential Scanning Calorimetry and coupled in-situ resistivity and X-ray diffractionmeasurements were performed. The whole results allowed us to suggest a mechanism of phase formation for each sample and by using theoretical models of growth we determined kinetic data on the phase formation.
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DESIGN AND OPTIMIZATION OF LOW-Cu AND Cu-FREE AUTOMOTIVE BRAKE FRICTION MATERIALSLee, Poh Wah 01 August 2013 (has links)
The purpose of this research was to generate the knowledge for formulating low-Cu and Cu-free brake friction materials without using and releasing hazardous materials that are listed on Washington State and California State Senate Bills. Model brake material samples were manufactured and tested in the Friction Assessment and Screening Test (FAST) and the full scale automotive brake dynamometer (Dyno) using a SAE J2430 test procedure. The SAE recommended a J2430 test procedure which provided the necessary data for the Brake Effectiveness Evaluation Procedure (BEEP) by the Brake Manufacturers' Council. The newly developed low-Cu and Cu-free brake friction materials were formulated by modifying a typical Non Asbestos Organic (NAO) (T-Baseline) formulation and a typical Semi-Metallic (M-Baseline) formulation. The NAO Cu-free brake friction materials contain geopolymer and natural hemp fibers as a partial replacement of phenolic resin and synthetic Kevlar fibers, respectively. Friction performance and wear data from a series of FAST tests were used to train an artificial neural network, which was used to optimize the NAO Cu-free formulations. Then, the optimized low-Cu and Cu-free brake friction materials were tested on the Dyno. Dyno test results showed that all NAO Cu-free brake friction materials have passed the Brake Effectiveness Evaluation Procedure (BEEP), did not exhibit thermal fade when temperature was increased and were slightly sensitive to speed. The NAO Cu-free brake friction materials exhibits slightly lower average friction level when compared to the baseline materials (T-Baseline). The Cu-free brake friction materials, as well as the rotors, exhibit higher wear than the detected wear on the T-Baseline material. The semi-metallic low-Cu and Cu-free brake friction materials have also passed the BEEP. Dyno test results indicated that the semi-metallic low-Cu and Cu-free friction materials did not exhibit thermal fade and were slightly sensitive to speed. The semi-metallic low-Cu and Cu-free materials exhibited lower friction level and higher wear on the pads when compared to the M-Baseline material. The semi-metallic Cu-free material outperformed the M-Baseline material in term of rotor wear. Analyses using scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) microanalysis on the tested materials show that the friction surface of the T-baseline material was covered with fully developed and stable friction layer (third body) consisting mostly of Fe-oxides, different forms of carbon and compounds of materials originally present in the bulk material. The NAO Cu-free materials (T30-15 and T30-16) did not develop a sufficient friction layer. The friction layer seemed to be responsible for the detected lower wear in the T-Baseline compared to the NAO Cu-free materials (T30-15 and T30-16), and it acted as a solid lubricant on the interface between the rubbing pad and the cast iron rotor lowering the adhesive forces. The friction and wear of the T-Baseline material was controlled by adhesive mechanisms. The NAO Cu-free materials (T30-15 and T30-16) with content of geopolymer replacing phenolic resin matrix exhibited extensive abrasive wear in addition to adhesive mechanisms. The capacity to form a friction layer on the surface plays a considerable role when lowering the wear of NAO brake friction materials. The friction layer was formed by compaction and interaction of brake wear particles, and its stability and character depend on the chemistry of the bulk materials in contact as well as the temperature, pressure and sliding speed during a friction process. SEM and EDX analyses also showed that the semi-metallic pads have developed friction layer on the friction surfaces. The difference was that the M-Baseline material had well developed friction layer, but the Low-Cu (M4) and Cu-free (M5) materials, had many smaller patches of friction layer disturbed on the surfaces.
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Avaliação da toxicidade, atividade antitumoral de 5-fluorouracil incorporado a redes de coordenação multifuncionaisLucena, Flávia Raquel Santos 31 January 2013 (has links)
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Previous issue date: 2013 / Relatos na literatura vêm utilizando nanoparticulas com o objetivo de carrear drogas e diminuir seus efeitos colaterais. Dentro dessa perspectiva estão às redes coordenadas a metais orgânicos ou MOFs. Este trabalho teve como objetivo realizar a incorporação de um fármaco antitumoral em uma rede de coordenação, visando melhorar sua biodisponibilidade para o organismo, bem como avaliar a toxicidade deste sistema in vitro e in vivo. Para isso foi realizado estudo teórico-computacional que nos permitiu a escolher o melhor fármaco a ser utilizado (5-fluorouracil) e a melhor rede de coordenação (Cu-BTC MOF), levando em consideração os tamanhos das moléculas dos mesmos em relação ao tamanho dos poros das MOFs Cu-BTC e MIL-53(Al). Os resultados das caracterizações químicas realizadas (UV-VIS, IV, CNHS, DRX, TGA/DTG e DSC) indicaram uma incorporação de 0,82 g de 5-fluorouracil para cada 1 g de MOF Cu-BTC após sete dias de agitação. A cultura celular in vitro demonstrou que o sistema 5-FU + Cu-BTC MOF apresentou atividade citotóxica significante quando comparado ao fármaco em solução. O teste de verificação do mecanismo de morte celular utilizando a citometria de fluxo indicou ser a apoptose o mecanismo de ação responsável para eliminação das células tumorais. O estudo de dissolução indicou uma liberação lenta e controlada de 39% do fármaco nos primeiros 30 minutos seguida da liberação de 82% do fármaco em 48 horas. Alterações histológicas só foram evidenciadas quando utilizada a dose de 750mg/kg sendo esta, a dose letal (DL50) encontrada. O teste da peritonite, verificação dos níveis de citocinas pro-inflamatórias e produção de óxido demonstraram que o sistema 5-FU + Cu-BTC MOF reduziu o número de leucócitos, os níveis de citocinas pró-inflamatórias e óxido nítrico, indicando que o sistema apresentou também atividade antiinflamatória para os testes realizados. Os resultados indicaram ser o sistema 5-FU+Cu-BTC MOF
um excelente carreador de fármaco, com indicação de atividade anti-inflamatória, excelente atividade citotóxica via mecanismo de apoptose e liberação lenta e gradual do fármaco, o que possibilitou a diminuição na toxicidade do mesmo acompanhado de uma significante melhora terapêutica.
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Estudo geocronológico das mineralizações sulfetatas de Fe-Cu em Skarns da região de Itatuba(PB), terreno alto Moxotó, províncía BorboremaANASTÁCIO, Emerson Marcello Ferreira. 18 July 2013 (has links)
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Previous issue date: 2013-07-18 / A área investigada situa-se entre Fagundes e Itatuba (PB), geologicamente inserida no Terreno Alto Moxotó (TAM), Subprovíncia Transversal (DZT), Província Borborema, Nordeste do Brasil. Localmente ocorre um conjunto de corpos tabulares, lenticulares e sub-elípticos, de uma suíte de rochas graníticas e metamáfico-ultramáficas com lentes de rochas metacarbonáticas associadas, além de skarns, encaixados em um embasamento gnáissico-migmatítico (Complexo Floresta). Lentes de rochas metamáficas-ultramáficas, pertencentes a uma série basalto-toleiítica com afinidades de MORB, hospedam importantes ocorrências de Fe-Ti. Os skarns abrigam uma associação de quartzo-epidoto-sulfetos (Fe-Cu), disposta em estruturas do tipo brechada e stockwork, formadas por hidrotermalismo tardio que pode ter gerado mineralizações com potencial interessante, (e.g. Fe, Cu, Au), como já constatado em outros skarns da Província Borborema. Visando elucidar de modo mais realístico o modelo genético da mineralização estudada, no contexto temporal do hidrotermalismo, foi realizado o estudo geocronológico da principal ocorrência de skarns mineralizados em Fe-Cu, utilizando-se o par isotópico Re-Os em calcopirita (sulfeto dominante na paragênese do minério estudado). Embora o erro nas análises das razões isotópicas entre Re e Os ter sido aceitável (< 1 %), as amostras de calcopirita analisadas registraram concentrações extremamente baixas de Re (7 a 20 ppb) e Os (6 a 98 ppb), que ocasionaram uma tendência não-linear no diagrama concórdia, não permitindo um cálculo preciso da idade. Assim, após várias tentativas de geração de idades interpretáveis diante do contexto geológico local, este cálculo foi feito individualmente para as quatro frações analisadas, sendo que as que forneceram dados plausíveis no contexto geológico da área retornaram idades entre 0,52 Ga (amostra YK-566-1) e 2,05 Ga (YK-566-4). Enquanto a idade obtida pela amostra YK-566-1 pode representar o momento da precipitação dos sulfetos na área, associado ao hidrotermalismo tardio, durante o Estágio 3 Cambriano (~520 Ma), a amostra YK-566-4 (2,05 Ga) provavelmente possui informações isotópicas herdadas do episódio juvenil mais antigo relatado até o momento (2308 ± 22,5 Ma) ou de seu metamorfismo posterior em 2,012 Ga. Embora os métodos utilizados não tenham permitido considerações e conclusões mais consistentes, face ao contexto geológico da área estudada como conhecido até o momento, os dados de Carmona (2006) combinados com os de Santos et al. (2013a), bem como os gerados neste trabalho, permitem, de fato, traçar uma evolução aceitável, onde a granitogênese neoproterozoica provavelmente seria a responsável pelo hidrotermalismo da área (~547 Ma), embora a mineralização primária de Fe-Cu provavelmente seja orosiniana (2,050-1,800 Ga).
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