Hierarchically Porous Gd3+-Doped CeO2 Nanostructures for the Remarkable Enhancement of Optical and Magnetic Properties

Rare earth ion-doped CeO2 has attracted more and more attention because of its special electrical, optical, magnetic, or catalytic properties. In this paper, a facile electrochemical deposition route was reported for the direct growth of the porous Gd-doped CeO2. The formation process of Gd-doped CeO2 composites was investigated. The obtained deposits were characterized by SEM, EDS, XRD, and XPS. The porous Gd3+- doped CeO2 (10 at% Gd) displays a typical type I adsorption isotherm and yields a large specific surface area of 135 m2/g. As Gd3+ ions were doped into CeO2 lattice, the absorption spectrum of Gd3+-doped CeO2 nanocrystals exhibited a red shift compared with porous CeO2 nanocrystals and bulk CeO2, and the luminescence of Gd3+-doped CeO2 deposits was remarkably enhanced due to the presence of more oxygen vacancies. In addition, the strong magnetic properties of Gd-doped CeO2 (10 at% Gd) were observed, which may be caused by Gd3+ ions or more oxygen defects in deposits. In addition, the catalytic activity of porous Gd-doped CeO2 toward CO oxidation was studied

Procedimiento de preparación de nanopartículas de aleaciones Ni-Sn y su uso en reacciones de reformado

Procedimiento de preparación de nanopartículas de aleaciones Ni-Sn y su uso en reacciones de reformado. La presente invención se refiere a un procedimiento para la preparación de nanopartículas de Ni-Sn que comprende - preparar una disolución de un carboxilato de níquel en el que dicho carboxilato tiene entre 1 y 6 átomos de carbono, y un halogenuro de estaño en un disolvente orgánico - añadir PVP (polivinilpirrolidona) - mantener en agitación hasta obtener una disolución homogénea, - añadir un compuesto reductor inorgánico, - poner a reflujo, obteniendo una disolución coloidal, - añadir un disolvente orgánico polar a la disolución coloidal resultante anteriormente, provocando la precipitación de un sólido, y al uso de dichas partículas en reacciones de reformado.Peer reviewedUniversidad de Sevilla, Consejo Superior de Investigaciones Científicas (España)A1 Solicitud de patentes con informe sobre el estado de la técnic

A new intersecting tunnel structure in the A(I)M(III)[PO3(OH)](2) series for A(I) = Ag, M-III = In: Analysis of structural relationships

International audienceA new indium hydroxyphosphate containing silver, AgIn[PO3(OH)](2), has been synthesized using hydrothermal method. It crystallizes in the P2(1)/c space group with the cell parameters a = 6.6400(2) angstrom, b = 14.6269(6) angstrom, c = 6.6616(4) angstrom, beta = 95.68](5)degrees, V = 643.82(6) angstrom(3), Z = 4. Its three-dimensional framework, built up of corner-sharing PO3(OH) tetrahedra and InO6 octahedra, presents intersecting tunnels running along \textless 111 \textgreater and [100] directions, in which the Ag+ cations are located. The presence of hydroxyl groups has been confirmed from IR spectroscopy studies and hydrogen atoms were located from the single crystal X-ray diffraction study. The structural relationships with the other compounds of general formula A(I)M(III)[PO3(OH)](2) are analyzed. (C) 2008 Elsevier Masson SAS. All rights reserved

A new intersecting tunnel structure in the A(I)M(III)[PO3(OH)](2) series for A(I) = Ag, M-III = In: Analysis of structural relationships

International audienceA new indium hydroxyphosphate containing silver, AgIn[PO3(OH)](2), has been synthesized using hydrothermal method. It crystallizes in the P2(1)/c space group with the cell parameters a = 6.6400(2) angstrom, b = 14.6269(6) angstrom, c = 6.6616(4) angstrom, beta = 95.68](5)degrees, V = 643.82(6) angstrom(3), Z = 4. Its three-dimensional framework, built up of corner-sharing PO3(OH) tetrahedra and InO6 octahedra, presents intersecting tunnels running along \textless 111 \textgreater and [100] directions, in which the Ag+ cations are located. The presence of hydroxyl groups has been confirmed from IR spectroscopy studies and hydrogen atoms were located from the single crystal X-ray diffraction study. The structural relationships with the other compounds of general formula A(I)M(III)[PO3(OH)](2) are analyzed. (C) 2008 Elsevier Masson SAS. All rights reserved

Gullies and badland landscapes in Neogene basins, region of Murcia, Spain

The area occupied by gullies and ravines in Murcia Region is 161,028 hectares, representing 14.63%. The origin of these erosive forms are related to several factors such as : lithological and stratigraphic features, mineralogy and geochemistry of the sediments, tectonics, climatic characteristics, low vegetation cover and poorly developed soils