Amethyst
Mostrando 1-11 de 11 artigos, teses e dissertações.
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1. Stratigraphy of amethyst geode-bearing lavas and fault-block structures of the Entre Rios mining district, Paraná volcanic province, southern Brazil
O distrito mineiro de Entre Rios produz um grande volume de geodos de ametista em minas subterrâneas e faz parte das jazidas de classe mundial da província vulcânica Paraná na América do Sul. Dois derrames de basalto são os produtores e têm números 4 e 5 na estratigrafia das lavas. Há sete derrames e um de riodacito no distrito. Na base da estratigr
An. Acad. Bras. Ciênc.. Publicado em: 2013-12
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2. Photo-induced dipole relaxation current in natural Amethyst
Thermally stimulated depolarization current (TSDC) measurements were carried out for SiO2 in the amethyst form, aiming to investigate the relationship of observed current with relaxation phenomena related to quartz impurities. In addition to TSDC conventional dark procedure, photo-induced TSDC was also carried out, where the exciting light came from an Ar+ l
Materials Research. Publicado em: 31/05/2012
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3. Caracterização de Gossans em depósitos de geodos de ametista e ágata nos distritos mineiros de Quaraí e Los Catalanes (Brasil e Uruguai), com uso de geoquimica de rochas e cintilometria
Nesse estudo é relatada a descoberta de um grande número de gossans na província vulcânica Paraná, América do Sul, com base em observações de imagens de satélite e trabalho de campo associado à geoquímica e geofísica. Define-se, portanto um novo guia prospectivo para depósitos de ágata e ametista. A área de estudo está localizada na fronteira
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2011
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4. Aplicações de microcospia eletrônica de varredura (MEV) e sistema de energia dispersiva (EDS) no estudo de gemas exemplos brasileiros
This paper presents results of SEM and EDS study in some Brazilian gemstones. Emerald from Campos Verdes (GO) contains several mineral inclusions as talc, dolomite, chromite, pyrite, magnetite, etc. Sylvite crystals was firstly identified by SEM/EDS. These salt inclusions suggest percolation of K-bearing fluids during emerald crystallization. Emerald from Ca
Publicado em: 2010
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5. Structural constraints on Paraná basalt volcanism and their implications on agate geode mineralization (Salto do Jacuí, RS, Brazil)
The Paraná-Etendeka Continental Flood Basalt province hosts world-class agate and amethyst geode deposits in Rio Grande do Sul (Brazil; Serra Geral Fm.). Salto do Jacuí Mining District (Rio Grande do Sul, Brasil) has different types of agate geode hosted in vesicular basalt. A series of structural features has recently been investigated in the Salto do Jac
Publicado em: 2010
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6. Infrared and chemical characterization of natural amethysts and prasiolites colored by irradiation
The infrared bands of amethyst and prasiolite samples from different origins were correlated to the trace elements contents. Amethysts have an iron content greater than 20 ppm and a low content of sodium and potassium. Prasiolites have an aluminum content greater than 120 ppm and a higher overall trace elements content, which accounts for a strong absorption
Materials Research. Publicado em: 2009-09
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7. RELAÇÃO ENTRE A COMPARTIMENTAÇÃO GEOMORFOLÓGICA E A OCORRÊNCIA DE ÁGATA E AMETISTA NO MUNICÍPIO DE QUARAÍ-RS / RELATION BETWEEN COMPARTMENTATION GEOMORPHOLOGIC AND THE OCCURRENCE OF AGATE AND AMETHYST IN THE QUARAÍ-RS BRAZIL.
The study of geomorphology takes place in the geographical science with the aid of other sciences such as geology. In these studies, the relief is a key element in the understanding of the relationship between the physical aspects (lithology, soil, vegetation, hydrography, climate, etc.) and the activities of human beings. Thus, to understand the interfaces
Publicado em: 2009
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8. Caracterização de Ametistas Naturais
This research intends to investigate the formation of color in samples of natural amethyst from different origins after submitting them to gamma irradiation, as well to develop an identification method of uncolored crystals with potential for development of color. The techniques of infrared spectroscopy, ultraviolet-visible spectroscopy and atomic emission s
Publicado em: 2008
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9. Caracterização espectral das rochas constituintes dos rejeitos de garimpo de pedra ametista - região de Ametista do Sul, Rio Grande do Sul. / Spectral characterization constituent rocks of the debris i panrock amethyst - South Amethyst region, Rio Grande do Sul, Brasil
O uso de imagens de sensores remotos para o mapeamento e discriminação de alvos geológicos está baseado nas propriedades da radiação eletromagnética solar refletida de unidades elementares da superfície do terreno (UEST). Nas imagens, os UEST estão codificados em números digitais, cujos valores correspondem à medida de um complexo processo de troc
Publicado em: 2008
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10. In Situ Population Dynamics of Bacterial Viruses in a Terrestrial Environment
Predation by bacteriophages is thought to control bacterial numbers and facilitate gene transfer among bacteria in the biosphere. A thorough understanding of phage population dynamics is therefore necessary if their significance in natural environments is to be fully appreciated. Here we describe the in situ population dynamics of three separate phage popula
American Society for Microbiology.
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11. Characterization of Six Bacteriophages of Serratia liquefaciens CP6 Isolated from the Sugar Beet Phytosphere
Six phages (ΦCP6-1 to ΦCP6-6) that are commonly found in the phytosphere of sugar beet (Beta vulgaris var. Amethyst) were investigated, and their relative impacts on their host (Serratia liquefaciens CP6) were compared. There were fundamental differences between the two most abundant predators of CP6 (ΦCP6-1 and ΦCP6-4). Like ΦCP6-2 and ΦCP6-5, ΦCP6-1
American Society for Microbiology.