Lanthanide
Mostrando 13-24 de 102 artigos, teses e dissertações.
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13. CONTRIBUIÇÃO AO ESTUDO DE CAMPO CRISTALINO E TRANSIÇÕES 4f-4f EM SISTEMAS CONTENDO LANTANÍDEOS. / CONTRIBUTION TO THE STUDY OF CRYSTAL AND FIELD 4F-4F TRANSITIONS IN SYSTEMS CONTAINING LANTHANIDES.
A theoretical study of the interactions between the 4f electrons in lanthanide ions (Ln3 +) with the chemical environment was made using crystal field theory. The main effects were studied: change in position of the berycentre of the energy levels of the free ion, maximum splitting of the J level and contribution to 5D0-7F0 transition of Eu3+ ion. Use of sec
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 18/09/2012
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14. Fases sólidas luminescentes contendo íons lantanídeos : uma proposta para determinação de ácido siálico.
The organofunctionalized silica was used as the solid support in the study of photophysical properties of lanthanides, in particular the Eu (III) ions, which functions as structural probe has been thoroughly discussed seeking new technological applications. In this study, were synthesized two novel organofunctionalized silica matrices and new lanthanide comp
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/02/2012
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15. Lanthanide nitrates as Lewis acids in the one-pot synthesis of 1,2,4-oxadiazole derivatives
Neste trabalho relatamos o uso de nitratos de lantanídeos [Ln(NO3)3] atuando como catalisador na síntese de uma única etapa de derivados de 3-benzoíla- e 3-acetila-1,2,4-oxadiazóis a partir de cetonas, nitrilas e ácido nítrico. Este é o primeiro exemplo da síntese em única etapa de preparação de derivados benzoíla e acetila-1,2,4-oxadiazóis, us
J. Braz. Chem. Soc.. Publicado em: 31/07/2012
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16. Synthesi and photoluminescent properties of bis-diketonate complexes of trivalent lanthanide ions with phosphine oxide ligands / Síntese e propriedades fotoluminescentes de complexos bis-dicetonatos de íons lantanídeos trivalentes com ligantes fosfinóxidos
Este trabalho relata a síntese, caracterização e a investigação das propriedades fotoluminescentes de complexos β-dicetonatos (TTA=2-tenoiltrifluoroacetonato e DBM= dibenzoilmetanato) de íons lantanídeos trivalentes (Ln3+= Gd3+, Eu3+ e Tb3+) com diferentes ligantes fosfinóxidos (TPPO= trifenilfosfinóxido e HMPA= hexametilfosforamida). Os dados
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 03/06/2011
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17. Síntese, Caracterização Estrutural e Propriedades Luminescentes de Complexos de Lantanídeos (III) com Hidrazonas e Semicarbazonas derivadas da 2,6-Diformilpiridina e com Triazenos 1-óxidos. / Synthesis, Structural Characterization and Luminescent Properties of Complexes of Lanthanides (III) with Hydrazones and Semicarbazones derived from 2,6-diformylpyridine and Triazenes 1-oxides.
Lanthanide complexes with ligands containing oxygen and nitrogen as donor atoms have been investigated in this study aiming to explore the coordinative behavior of metals with high coordination numbers, as well as a study of luminescence properties of new complexes. The chosen ligands were hydrazones and semicarbazones derived from 2,6-diformylpyridine and t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 201103
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18. Estudos das propriedades ópticas dos complexos európio tetraciclinas e suas aplicações na detecção de lipoproteínas / Studies of optical properties of complexes europium tetracycline and its applications in detection of lipoproteins
This work presents the optical properties of europium complexes - Tetracyclines (EuTcs) in the presence of LDL and oxidized LDL with potential applications in clinical analysis. Four elements were chosen from the Tetracyclines family: Tetracycline (Tc), Chlortetracycline (CTc), Metatetraciclina (MTc) and Oxytetracycline (OTc) to be part of complexes with eur
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/07/2010
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19. DESENVOLVIMENTO DE UM NOVO MARCADOR LUMINESCENTE PARAMICROCISTINA-LR: um estudo teórico. / DEVELOPMENT OF A NEW luminescent PARAMICROCISTINA-LR: a theoretical study.
In this work we describe a theoretical study of lanthanide complexes with macrocyclic ligands. Spectroscopic properties of the cryptate [EuÌ(bipy)2py(CO2Et)2]3+.2H2O were investigated with semiempirical methodologies such as Sparkle, INDO/S-CIS, Judd- Ofelt model as well as Maltas models implemented in LUMPAC (Luminescence Package). This computational packa
Publicado em: 2010
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20. Synthesis, characterization and thermal behaviour of heavy trivalent lanthanide malonates
Compostos Ln-L no estado sólido, em que Ln representa os lantanídeos trivalentes (Tb - Lu) e L é malonato, foram sintetizados neste trabalho. A termogravimetria e análise térmica diferencial simultânea (TG-DTA), calorimetria exploratória diferencial (DSC), difratometria de raios X pelo método do pó, espectroscopia na região do infravermelho (FTIR),
Eclética Química. Publicado em: 2010
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21. Processamento e estudo de ortoniobatos de terras raras e ortotungstatos de metais alcalinos terrosos
Two classes of orthoceramic compounds of general formula ABO4 were investigated in this work. The first group includes the lanthanide orthoniobates (RENbO4, RE = La-Lu, except Pm), which were synthesized by conventional solid-state route at 1150C in different conditions of time aiming the production of crystalline, single phase materials. Alkaline- earth-met
Publicado em: 2010
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22. Estudo teórico das espécies heterobimetálicas laGa, ceGa, euGa e ybGa em fase gasosa .
The current dissertation deals with the study of electronic structure elucidation of gas phase neutral heterobimetallic species LnGa(Ln=La, Ce, Eu, Yb) using relativistic effective core potentials. Lanthanides are of a great interest in different areas of chemistry: coordination chemistry, organometallic chemistry and catalysis. An expectation is that Ln-Ga
Publicado em: 2009
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23. SPECTROSCOPIC CHARACTERIZATION OF HYPOCRELLIN B: LANTHANIDE COMPLEXES FOR USE IN PHOTODYNAMIC THERAPY / Caracterização espectroscópica de complexos hipocrelina B: lantanídeos para uso em terapia fotodinâmica
A study about the optical properties of the chromophore hypocrellin B (HB) and of its complexes with lanthanum (La3+), europium (Eu3+) and terbium (Tb3+) ions in ethanol solutions was realized. This pigment is a potential second generation photosensitizer due to its great properties, as high in vivo metabolism and mainly high singlet oxygen generation quantu
Publicado em: 2009
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24. Synthesis and magnetic studies of copper(II)-lanthanide(III) 5-bromosalicylideneglycylglycine
The physico-chemical properties of the new 3d-4f heteronuclear complexes with general formula LnCu3(C11H8N2 O4Br)3·13H2O (where Ln = Pr, Eu, Gd, Tb, Er, Yb and H3(C11H8N2 O4Br) - 5-bromosalicylideneglycylglycine) were studied. The compounds were characterized by elemental, spectral and thermal analyses and magnetic measurements. The formation of Schiff base
Eclética Química. Publicado em: 2009