Terbium
Mostrando 13-24 de 38 artigos, teses e dissertações.
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13. Synthesis of rare earths benzenetricarboxylate complexes and study of their photoluminescent properties / Síntese de complexos benzenotricarboxilatos de terras raras e estudo de suas propriedades fotoluminescentes
O presente trabalho aborda a síntese e caracterização de complexos benzenotricarboxilatos de íons Eu3+, Gd3+ e Tb3+, com o intuito de investigar suas características químicas e estruturais e correlacioná-las com as propriedades fotoluminescentes. Os complexos benzenotricarboxilato [TR(BTC)(H2O)n] foram sintetizados em solução aquosa, e apresentaram-
Publicado em: 2008
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14. Construction of a novel potentiometric terbium(III) membrane sensor and its application for the determination of terbium ion in binary mixture and fluoride ion in a mouth wash preparation
Um novo sensor potenciométrico constituído por uma membrana de PVC, altamente seletivo a íons Tb(III) foi preparado usando-se 4-amino-3-{2-[4-amino-6-metil-5-oxo-4,5-diidro-1,2,4 -triazina-3(2H)-ilidina] hidrazono}-6-metil-3,4-diidro-1,2,4-triazina-5(2H)-ona (ATO) como um carregador adequado. O sensor trabalha satisfatoriamente no intervalo de concentraç
Journal of the Brazilian Chemical Society. Publicado em: 2006-12
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15. A fluorescent-labeled microcystin-LR terbium cryptate
Um novo composto fluorescente de microcistina-LR marcado com criptato de térbio foi obtido pela conjugação inicial da microcistina-LR com aminoetanotiol, seguido pela reação com o grupo éster do criptato de térbio. A formação do produto foi acompanhada por cromatografia líquida de alta eficiência (CLAE) em 238 nm e 310 nm. A presença de microcist
Journal of the Brazilian Chemical Society. Publicado em: 2006-04
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16. Sistemas Trinucleares Contendo Ãons LantanÃdeos
Aiming to develop new ligands capable to coordinate most of one lanthanide ions, this work shows the synthesis of trinuclear systems for photonics applications and characterization by elemental analysis, spectroscopic methods (infrared, electronic absorption and NMR of 1H and 13C). A particular study, about the new compounds synthetized, shows the substituti
Publicado em: 2006
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17. Uma investigaÃÃo teÃrica e experimental das propriedades luminescentes de novos complexos de lantanÃdeos com β-cetoÃsteres
The theoretical and experimental study of the luminescent properties of the complexes of trivalent europium, terbium and gadolinium ions with β-ketoesthers, ethyl 4,4,4-trifluoroacetoacetate (ETA), ethyl acetoacetate (EAA), methyl 4-methoxy acetoacetate (MMA) and ethyl benzoilacetoacetate (EBA) ligands revealed a new class of complexes that present opti
Publicado em: 2005
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18. Síntese, caracterização e propriedades espectroscópicas de criptatos de lantanídeo do tipo [LnÌ(bipy)2py(CO2Et) 2(3+)]
This work reports on the synthesis, characterization (infrared and hidrogen nmr spectra) and photophysical properties (luminescence spectra and emission quantum yield) of the lanthanide cryptates [LnÌ(bipy)2py(CO2Et) 2]3+ with Ln = Eu3+, Tb3+ or Gd3+, which can be applied as efficient Light-Conversion-Molecular-Devices. From emissio
Química Nova. Publicado em: 2004-10
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19. Estudo da interação entre sistemas luminescentes e alfa e beta-ciclodextrina em solução aquosa / Study of luminescent materials in aqueous solution by interaction with alfa and beta cyclodextrin
In recent years, there has been considerable research on the study of energy transfer process by active optically ions due to their great importance in solid state devices, e.g., lasers and optic-electronic materials. These luminescent materials in aqueous solution can also be very useful as sensors or probe in biomaterials analysis. In this context, the int
Publicado em: 2004
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20. Novos macrociclos de lantanÃdeos: marcadores fotÃnicos projetados para aplicaÃÃes biotecnolÃgicas
The present work describes the synthesis, characterization and photophysical properties of the lanthanide cryptates [Ln⊂(bipy)2py(CO2Et)2]3+ and [Ln⊂(bipy)2py(CONHCH2CH2NH2)2]3+ with Ln3+ = Eu3+, Tb3+ and Gd3+, which are efficient light conversor molecular devices in aqueous solution. Emission spectroscopic analysis and lifetime measurements at 2
Publicado em: 2003
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21. Desenvolvimento de mÃtodos para determinaÃÃo de microcistina-lr em Ãgua
In the search for methods for microcystins analysis that are easy to use, low cost and with sufficient high sensitivity to following the recommendations of the World Health Organization âWHO and the Brazilian legislation, was developed a specific dot blot assay. This dot blot imnunoassy is for visual determination of microcystin-LR in purified and sufarce w
Publicado em: 2003
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22. Síntese e espectroscopia de sistemas envolvendo tungstatos e íons de terras raras / Synthesis and spectroscopy of system envolving tungstates and rare earth ions
The studies about the photoluminescent properties of the rare earth tungstates Eu2(WO4)3 and Gd2(WO4)3:RE3+ (RE3+ = Eu, Sm and Tb) obtained via three different methods of preparation were reported: i) ceramic method, which is the older one and uses high temperatures (>1000 ºC) and long periods of heating, with the physical mixture of the reagents in the pow
Publicado em: 2003
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23. Modificações do DNA por acetona triplete gerada na oxidação de 2-metilpropanal em presença de peroxidase
Incubation of 2-methylpropanal in air saturated buffer causes an oxidation reaction initiated by the formation of peroxidase compound-I (HRP-I) and then HRP-II to produce acetone in its excited state and formic acid. The optimun pH is around 7,0 and kM is 30 mM at 40°C. Experiments in the presence and absence of metal ions suggested that peroxidase uses the
Publicado em: 1982
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24. Contribuição magnetoelastica para as constantes elasticas do terbio monocristalino
We have investigated the behavior of the 2nd order elastic constants of single-crystal terbium, with the state of magnetization of the material, in magnetic fields up to 73 kOe, between 4.2 and 300 K, range that includes 3 kinds of magnetic ordering: ferromagnetic , helical antiferromagnetic ( T<221 K ) and paramagnetic (221 K
Publicado em: 1978