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Caracterização de sistemas vítreos baseados no formador B2O3 e P2O5 dopados com CeO2
(Universidade Estadual Paulista (Unesp), 2006-08-01)
Neste trabalho, foram sintetizados vidros boratos e fosfatos dopados com diferentes concentrações de CeO2 dos sistemas B2O3 – BaO – K2O – CeO2 (BBKC), P2O5 – Na2O – PbO –ZnO – CeO2 (VCKT) e P2O5 – Na2O – CdO –La2O3 – CeO2 ...
CeO2 and Co3O4-CeO2 nanoparticles: effect of the synthesis method on the structure and catalytic properties in COPrOx and methanation reactions
(Springer, 2016-04)
CeO2 and Co3O4–CeO2 nanoparticles were synthesized, thoroughly characterized, and evaluated in the COPrOx reaction. The CeO2 nanoparticles were synthesized by the diffusion-controlled precipitation method with ethylene ...
Thermal stability of the cu-ceo2 interface on silica and alumina, and its relation with activity in the oxidation reaction of co and the decomposition of n2o
(Sociedad Chilena de Quimica, 2018)
The effect of the support on the formation of the Cu-CeO2
interface and its thermal stability after calcination at 500, 700 and 900 ºC is studied. The supports
used are SiO2
, because of its inert character, and ...
Reduced CeO2 (111) ordered phases as bulk terminations: Introducing the structure of Ce3O5
(American Physical Society, 2018-08)
Reduced ceria (CeO2−x ) has a rich phase diagram comprising a variety of bulk phases with stoichiometries ranging from CeO2 to Ce2O3 as the reduction conditions are increased. Some observed reduced ceria (111) surface ...
Estudo da atividade fotocatalítica de filmes finos multicamadas de TiO2/CeO2.
(Universidade Federal do Rio Grande do NorteBrasilUFRNEngenharia de Materiais, 2019-05-31)
The use of thin films in photocatalytic processes is widely studied because unlike materials in the form of powder, do not generate secondary residues. However, thin films must have good chemical stability and oxidative ...
Cobalt based catalysts for CO Preferential Oxidation
(IntechOpen, 2019)
In this work, catalysts based oncobalt supported on ZrO2 and CeO2, and CoCeMnOx were studiedfor the CO preferential oxidation (COPrOx) in rich-hydrogen stream able to feedfuel cells. Among them, the CoCeMnOx formulation ...
Time-resolved spectroscopy studies of Gd2SiO5 : Ce3+ from spherical particles
(Elsevier B.V., 2002-10-07)
This paper reports on time-resolved emission and excitation spectra measurement studies of Gd2SiO5:Ce3+ in powder or pellet samples, from spherical particles, in order to assign the Ce3+ ion transitions into two different ...
In situ X-ray absorption spectroscopy study of CuO-NiO/CeO2-ZrO2 oxides: redox characterization and its effect in catalytic performance for partial oxidation of methane
(Royal Soc Chemistry, 2018)
In this work we analyze the effect of adding CuO to a NiO/Ce0.9Zr0.1O2 oxide by in situ X-ray absorption near-edge structure XANES technique in Ce L3, Ni K and Cu K absorption edges in terms of sample reducibility and ...
Estudo do efeito da adição de Au, Pd e Pt em catalisadores Cu/CeO2 aplicados à reação de deslocamento gás-água a baixa temperatura
(Universidade Federal de São CarlosBRUFSCarPrograma de Pós-Graduação em Engenharia Química - PPGEQ, 2008-07-02)
Cu/CeO2 catalysts doped with Au, Pd or Pt (WGSR) were prepared and applied in water gas shift reaction. The CeO2 support was prepared by four different way: urea co-precipitation-gelation (CeO2-UGC), hydrothermal method ...