U Pb
Mostrando 1-12 de 326 artigos, teses e dissertações.
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1. Naturally-Occurring Radioactive Materials at water treatment plant on the Poços de Caldas Plateau Region, Brazil
RESUMO Petróleo e gás, mineração, estações de tratamento de água, entre outros, são exemplos de instalações que podem apresentar Materiais Radioativos de Ocorrência Natural. Neste estudo, objetivou-se avaliar a presença de séries radioativas naturais, especialmente as de 238U e 232Th nas estações de tratamento de água da cidade de Poços de C
Engenharia Sanitaria e Ambiental. Publicado em: 2022
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2. Evaluation and Geostatistical Study of Toxicological Risk by Water Ingestion with Al, Ba, Fe and Pb in Communities Close to Industrial Areas in the Brazilian Amazon
This study provides a risk assessment and risk maps related to the consumption of water contaminated by Al, Ba, Fe and Pb in an industrial area in the Brazilian Amazon. A total of 120 samples of drinking water were collected from 26 locations in the municipality of Barcarena, Pará State. Multiple elements were analyzed by inductively coupled plasma optical
J. Braz. Chem. Soc.. Publicado em: 2020-07
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3. Ediacaran emerald mineralization in Northeastern Brazil: the case of the Fazenda Bonfim Deposit
Abstract The Fazenda Bonfim emerald deposit lies within the Seridó Belt. It is a classic example of deposit formed through metasomatic interactions between Be-rich granite intrusions and Cr(± V)-rich mafic-ultramafic rocks. The setting of the emerald mineralization was built under strong strike-slip dynamics, which produced serpentinization and talcificati
Braz. J. Geol.. Publicado em: 13/01/2020
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4. Digital mapping of soil attributes using machine learning
RESUMO O mapeamento de atributos químicos do solo em larga escala pode acarretar em ganhos no planejamento de uso e ocupação do mesmo. Existem diferentes técnicas disponíveis para tal fim, cujos desempenhos devem ser testados para diferentes situações de paisagem. Objetivou-se neste trabalho espacializar atributos químicos do solo, comparando oito m�
Rev. Ciênc. Agron.. Publicado em: 04/11/2019
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5. Lithogeochemical and Nd-Sr isotope data of the orthogranulites of the Juiz de Fora complex, SE-Brazil: insights from a hidden Rhyacian Orogen within the Ribeira belt
Abstract New petrography, geochemistry and Sm-Nd and Sr data from the orthogranulites of the Juiz de Fora complex in southern Rio de Janeiro State and compiled information provide insights on the petrogenetic and tectonic evolution. The complex comprises several geochemical groups including mafic orthogranulites (three tholeiitic and one alkaline) and felsic
Braz. J. Geol.. Publicado em: 24/10/2019
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6. Pseudosection modeling and U-Pb geochronology on Piranga schists: role of Brasiliano Orogeny in the Southeastern Quadrilátero Ferrífero, Minas Gerais, Brazil
ABSTRACT In the Southeastern Quadrilátero Ferrífero, a package of metapelitic rocks previously attributed to the Archean Rio das Velhas Supergroup crops out in Piranga locality. This study presents the mineral chemistry and U-Pb-Hf zircon geochronology on foliated staurolite-garnet mica schists. Garnet and staurolite index minerals are syn- to post-kinemat
Braz. J. Geol.. Publicado em: 21/10/2019
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7. U-Pb SHRIMP dating of basement rocks of the Iriri-Xingu domain, Central Amazonian province, Amazonian craton, Brazil
Abstract The Iriri-Xingu domain, located in the central part of the Amazonian craton, consists of extensive occurrences of Paleoproterozoic volcanic rocks and granites with published ages of ca. 1990 to 1840 Ma, which show a strong crustal contribution for their magmas. Exposures of basement rocks are small and rare. Samples from two areas were dated in this
Braz. J. Geol.. Publicado em: 21/10/2019
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8. Chemosensor Development of Cu2+ Recognition Using 1,5-Diphenylthiocarbazone: Optimization, COSMO-RS and DFT Studies
The sensitive and selective chemosensor for copper(II) ions (Cu2+) was successfully optimized using the 1,5-diphenylthiocarbazone (DPT) compound. The result showed that dimethyl sulfoxide (DMSO) in a 9:1 (DMSO:water) ratio at a pH of 3 was the optimum medium for DPT to act as chemosensor of Cu2+ recognition. The DPT chemosensor did not encounter any interfer
J. Braz. Chem. Soc.. Publicado em: 16/09/2019
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9. Geochemistry, Sm-Nd isotopes and SHRIMP U-Pb geochronology of the Morro do Coco Granite (RJ, Brazil): another piece of the post-collisional magmatism of the Ribeira Belt
Abstract The Morro do Coco granite (MC) is a post-collisional intrusive body that was emplaced at Ribeira Belt, in the Cambro-Ordovician, succeeding the final stages of the Gondwana supercontinent amalgamation. This unit requires more studies, contrasting with similar best investigated occurrences of the central Ribeira Belt. This work presents a detailed in
Braz. J. Geol.. Publicado em: 12/09/2019
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10. Geochronological systematics of the Huayna Potosí, Zongo and Taquesi plutons, Cordillera Real of Bolivia, by the K/Ar, Rb/Sr and U/Pb methods
Abstract The Huayna Potosi, Zongo and Taquesi are Triassic plutons located at the core of the Real Cordillera of Bolivia. In this paper, several Rb-Sr and K-Ar ages obtained in the past at the São Paulo Geochronology Laboratory, yet unpublished, will be presented, along with newer U-Pb Sensitive High-Resolution Ion Microprobe (SHRIMP) determinations made in
Braz. J. Geol.. Publicado em: 01/07/2019
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11. Provenance of the Ediacaran Salinas Formation (Araçuaí Orogen, Brazil): Clues from lithochemical data and zircon U-Pb (SHRIMP) ages of volcanic clasts
Abstract Salinas Formation occurs in a large region of the Northern Araçuaí orogen, Southeastern Brazil. It includes turbiditic wackes (> 10% matrix) to arenites (< 10% matrix), pelites and clast-supported conglomerates, metamorphosed from the biotite zone of the greenschist facies to the sillimanite zone of the amphibolite facies. Salinas Formation lies u
Braz. J. Geol.. Publicado em: 01/07/2019
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12. Epidermal morphology of the cordaitalean leaf Noeggerathiopsis brasiliensis nom. nov. from the southern Paraná Basin (Lower Permian, Rio Bonito Formation) and paleoenvironmental considerations
Abstract A Brazilian cordaitalean leaf is reassigned and redescribed based on cuticular analysis. The new name Noeggerathiopsis brasiliensis is erected as a replacement for Rufloria gondwanensis Guerra-Sommer. The leaf adpressions come from a tonstein layer within a Sakmarian coal seam of the Faxinal Coalfield, southern Paraná Basin, Brazil (U-Pb SHRIMP mea
Braz. J. Geol.. Publicado em: 01/07/2019