Species Metallic
Mostrando 13-24 de 85 artigos, teses e dissertações.
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13. Fitoextração em solo contaminado com metais pesados / Phytoextraction of soil contaminated with heavy metals
The industrial and urban progress associated with increased production of consumer goods has resulted in the generation of waste, which, for a long time, was indiscriminately discarded in the environment, causing damage usually irreversible to recover. Two experiments were conducted in soils contaminated with heavy metals: the first aimed at the disposal of
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 25/07/2011
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14. Study of the Reactivity of complex ions cis-[Ru (bpy)2(L) (NO)]n+ where L = imidazole, 1-metilimidazole, thiourea and sulfite / Estudo da Reatividade dos Ãons complexos cis-[Ru(bpy)2(L)(NO)]n+ onde L=imidazol, 1-metilimidazol, tioureia e sulfito
We carried out studies of chemical reactivity, electrochemistry and photochemistry of complexes cis-[Ru(bpy)2(L)(NO)](PF6)n, where L = imidazole, 1-methylimidazole, thiourea and sulfite. Were chosen, therefore, two ligands being donors and two with ligands that act as -recipient and the results indicated that the nature and strength of these
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 28/01/2011
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15. Modelo matemático multigrãos e multifásico para a previsão da solidificação equiaxial. / Multigrain and multiphase mathematical model for prediction of the equiaxed solidification.
Properties of components obtained by solidification processes depend strongly on the final grain structure. In the past few decades, there has been a significant breakthrough in the mathematical modeling of metallic alloy solidification to predict the grain macrostructure. Nevertheless, the so-called deterministic models are still not capable of modeling the
Publicado em: 2011
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16. Sintese de nanotubos de carbono por CVD utilizando catalisadores à base de ferro e molibdênio suportados em matrizes cerâmicas
Molybdenum is known for its synergistic effect in the synthesis of carbon nanotubes (CNs) by chemical vapor deposition (CVD method). When added to typical catalysts like iron, nickel, and cobalt, even in small quantities, it is increases the yield of these nanostructures. The presence of Mo also has an influence on the type and number of CN walls formed. Alt
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/02/2010
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17. Preparation and characterization oF Ru-Sn/Al2O3 catalysts for the hydrogenation of fatty acid methyl esters
Ru-Sn/Al2O3 catalysts with different Sn loadings were prepared by the coimpregnation method. Several characterization techniques such as TPR, pyridine TPD and catalytic tests for dehydrogenation and hydrogenolysis were used to evaluate and compare such catalysts. TPR results indicate that Sn is deposited both onto the support and as species strongly interact
Química Nova. Publicado em: 2010
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18. APLICAÇÃO DE MÉTODOS VOLTAMÉTRICOS DE ANÁLISE NA ESPECIAÇÃO DE CROMO, SELÊNIO E ANTIMÔNIO EM MATRIZES SALINAS / APPLICATION OF VOLTAMMETRIC METHODS TO THE SPECIATION ANALYSIS OF CHROMIUM, SELENIUM AND ANTIMONY IN SALINE MATRICES
This work aimed to explore the speciation analysis of chromium, selenium and antimony, elements of clinical and geochemical relevance, in the saline samples seawater, hydrothermal fluid and hemodialysis fluid. These samples, although linked to different research areas, have many similarities relating to their chemical compositions or the presence of metallic
Publicado em: 2010
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19. Removal of Cd+2 from aqueous solutions onto polypyrrole coated reticulated vitreous carbon eletrodes
The development of simple methods for removal of heavy metals from aqueous samples is a relevant field of research. In this connection, the electrodeposition of the Cd+2 ion, one of the most toxic species for animals and human beings, was investigated in aerated pH 4.8 sulfuric-sulfate solutions. In potentiostatic conditions, the maximum rate of cadmium depo
Publicado em: 2010
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20. Diagnose de microbiólitos metálicos em espécies vegetais endêmicas em solos de rochas ultramáficas por microscopia eletrônica de varredura
The aim of this paper is to investigate by SEM the presence of crystalline forms of noble metals in dehydrated tissues of Scutia buxifolia (Rhamnaceae), Scoparia montevidensis (Scrophulariaceae) and Adiantopsis cf. chlorophylla (Pteridaceae), a endemic vegetation on ultramafic soils from Pedras Pretas, São Sepé, southermost Brazil. Chemical composition of
Publicado em: 2010
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21. AVALIAÇÃO VOLTAMÉTRICA DOS ÍONS METÁLICOS (COBRE, CÁDMIO E CHUMBO) EM AMOSTRAS DE COMBUSTÍVEIS PREVIAMENTE DIGERIDAS EM MICROONDAS USANDO ELETRODO QUIMICAMENTE MODIFICADO POR SAIS TETRAZÓLIOS / EVALUATION OF METAL IONS VOLTAMMETRY(COPPER, CADMIUM AND LEAD) IN SAMPLES OF FUELS PREVIOUSLY DIGESTED IN USING MICROWAVE ELECTRODE CHEMICALLY MODIFIED BY SALTS TETRAZOLIUM.
This paper describes an analytical procedure for determination of trace metals copper, cadmium and lead in fuel samples, using Basal Plane Pyrolytic Graphite Modified Electrode (BPPGME) by tetrazolium salts: ([3,3 - (3-3 -dimethoxy-4, bifenililen 4 -bis [2 - (4-nitrophenyl)-5-phenyl-2H-tetrazolium (NBT) Cl 3 - (4,5 - dimetitiazol-2il) -2,5-diphenyl-2H-Tetraz
Publicado em: 2010
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22. Evaluation techniques coupled to mass spectrometry (ICP-MS) aimed at the fractionation and chemical speciation of mercury in blood and plasma / Avaliação de técnicas acopladas à espectrometria de massas com plasma (ICP-MS) visando o fracionamento e a especiação química de mercúrio em sangue e plasma
Mercury (Hg) is one of the most toxic environmental pollutants. It exists primarily in three forms: elemental mercury (Hg0), or metallic mercury, inorganic mercury (Hg-i), particularly mercuric chloride and organic mercury (Hg-o), mainly represented by methylmercury (MeHg) and ethylmercury (EtHg), and the organic forms of mercury are more toxic than the inor
Publicado em: 2010
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23. Effects of genetically modified cotton (Bollgard®) on non-target organisms / Efeitos do algodoeiro geneticamente modificado (Bollgard®) em organismos não-alvo
The effects of the genetically modified cotton (Bollgard®) expressing Bacillus thuringiensis (Bt) Cry1Ac toxin on non-target arthropods was evaluated under laboratory and field studies. Evaluations of arthropod abundance on Bollgard® cotton (Delta Pine 90) and on its isoline (Acala 90) were carried out during three consecutive field seasons. The first stud
Publicado em: 2010
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24. Transformações na matéria orgânica nos sedimentos e águas eutrofizados da Represa Ibirité (Ibirité-Sarzedo, MG) tratados com nitrato de cálcio em microcosmos
Due to the growing concern with the environment and the welfare of future generations the search for the restoration of degraded areas and the reestablishment of equilibrium between the anthropogenic and natural environments are nowadays highlighted. The Ibirité Reservoir (Ibirité-Sarzedo, MG) is an example of water body impacted by the disorganized urbani
Publicado em: 2010