Lanthanum
Mostrando 25-36 de 149 artigos, teses e dissertações.
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25. Degradação do PMMA através da reação despolimerização uitlizando catalisadores de óxidos mistos
In this work, mixed oxides were synthesized by two methods: polymeric precursor and gel-combustion. The oxides, Niquelate of Lanthanum, Cobaltate of Lanthanum and Cuprate of Lanthanum were synthesized by the polymeric precursor method, and treated at 300 C for 2 hours, calcined at 800 C for 6h in air atmosphere. In gel-combustion method were produced and oxi
Publicado em: 2009
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26. Desenvolvimento de catalisadores para reforma e oxidação combinadas do metano
In this work, we studied the effects of the promoters of support (ZrO2, La2O3, CeO2, CeO2-ZrO2, CeO2-ZrO2-La2O3 and La2O3) in the nickel catalysts supported on γ-Al2O3 were studied. The supports were prepared by wet impregnation on γ- Al2O3 (Alfa Aesar) with 10% by weight of oxides of cerium, zirconium, lanthanum, ceria-zirconia, ceria-lanthanum an
Publicado em: 2009
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27. Processamento Coloidal de Cromito de Lantânio / LANTHANUM CHROMITE COLLOIDAL PROCESSING
Lanthanum chromite (LaCrO3) is currently the most studied material for applications such as solid oxide fuel cell interconnector (HTSOFC). The complexity of microstructures and geometries of HTSOFC devices, require a precise control of processing parameters to get the desired combination of properties and this, the use of techniques involving concentrated ce
Publicado em: 2009
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28. Lanthanum based high surface area perovskite-type oxide and application in CO and propane combustion
The perovskite-type oxides using transition metals present a promising potential as catalysts in total oxidation reaction. The present work investigates the effect of synthesis by oxidant co-precipitation on the catalytic activity of perovskite-type oxides LaBO3 (B= Co, Ni, Mn) in total oxidation of propane and CO. The perovskite-type oxides were characteriz
Eclética Química. Publicado em: 2009
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29. Preparação e caracterização de materiais ferroelétricos de composição Bi4Ti3O12 contendo Lantânio e Érbio / Synthesis and characterization of Bi4Ti3O12 ferroelectric materials containing Lanthanum and Erbium
This work describes a systematic study of the influence of the lanthanum atom addition in the Bi4Ti3O12 (BIT) phase and the erbium atom addition in the Bi3,25La0,75Ti3O12 (BLT075) phase in terms of their synthesis process and its structural, microstructural and electrical properties. Ceramics of nominal composition Bi4-xLaxTi3O12 (BLTx) with 0 x 2 mol% and B
Publicado em: 2009
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30. Óxidos do tipo perovskita para reação de redução de no com CO
In this work, the perovskite-type oxides LaNiO3, LaMnO3, La0,7Sr0,3NiO3 and La0,7Sr0,3MnO3 were prepared by co-precipitation and tested in the NO reduction with CO at 400 and 500 ºC for 10 h. The catalysts were characterized by X-ray diffraction, temperature programmed reduction with hydrogen, nitrogen adsorption and chemical analysis. The nonstoichiometric
Química Nova. Publicado em: 2009
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31. SYNTHESIS AND CERAMIC PROCESSING OF ALUMINA AND ZIRCONIA BASED COMPOSITES INFILTRATED WITH GLASS PHASE FOR DENTAL APPLICATIONS / Síntese e processamento de compósitos á base de alumina e zircônia com infiltração de fase vítrea para aplicações odontológicas
The interest for the use of ceramic materials for dental applications started due to the good aesthetic appearance promoted by the similarity to natural teeth. However, the fragility of traditional ceramics was a limitation for their use in stress conditions. The development of alumina and zirconia based materials, that associate aesthetic results, biocompat
Publicado em: 2009
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32. 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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33. Estudo da inversão de carga em filmes de Langmuir / Study of the charge inversion in Langmuir films.
The study of charged interfaces is important for understanding several phenomena in polymer and colloid science, as well as in molecular biology. Even though this topic has benn extensively investigated, there are many open issues, such as details of ion-ion interactions. In this context, this work investigates charge inversion in Langmuir films of DMPA (dim
Publicado em: 2009
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34. LETUCE, CORN, SOYBEAN AND BEAN SEEDS TREATMENT WITH RARE EARTH ELEMENTS CERIUM AND LANTHANUM / TRATAMENTO DE SEMENTES DE ALFACE, MILHO, SOJA E FEIJÃO COM OS ELEMENTOS TERRAS RARAS CÉRIO E LANTÂNIO
Os elementos terras raras, ou lantanídeos, são comumente fornecidos às plantas na agricultura chinesa, na forma de fertilizantes. No Brasil não há qualquer registro de sua utilização na agricultura. Conduziram-se experimentos com o objetivo de avaliar os efeitos dos elementos terras raras, cério (Ce) e lantânio (La), sobre a qualidade fisiológica d
Publicado em: 2009
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35. Geração de H2 a partir do etanol : efeito da adição de terras raras (La2O3, CeO2) e Pt nas propriedades atalíticas de Co/Al2O3 para reforma do etanol
Ni or Co catalysts supported on Al2O3, La2O3-Al2O3 and CeO2-Al2O3 were prepared by impregnation of Al2O3 with an aqueous solution of lanthanum nitrate or ceria, followed by a calcination and incipient wetness impregnation with an aqueous solution of nickel or cobalt nitrate and promoted with Ag or Pt. The catalysts were characterized by temperature-programme
Publicado em: 2009
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36. Síntese e caracterização de catalisadores nanométricos de LaSrNiO4 para aplicação em dessulfurização de tiofeno
Os óxidos metálicos mistos constituem uma importante classe de materiais catalíticos mundialmente investigados em diferentes campos de aplicações. Estudos envolvendo niquelatos de terras raras vêm sendo realizados por vários pesquisadores no intuito de investigar a estabilidade proporcionada pelo óxido estrutural formado e a existência de propriedad
Publicado em: 2009