76 research outputs found
Enhancement of Rabi Splitting in a Microcavity with an Embedded Superlattice
We have observed a large coupling between the excitonic and photonic modes of
an AlAs/AlGaAs microcavity filled with an 84-({\rm {\AA}})/20({\rm {\AA}})
GaAs/AlGaAs superlattice. Reflectivity measurements on the coupled
cavity-superlattice system in the presence of a moderate electric field yielded
a Rabi splitting of 9.5 meV at T = 238 K. This splitting is almost 50% larger
than that found in comparable microcavities with quantum wells placed at the
antinodes only. We explain the enhancement by the larger density of optical
absorbers in the superlattice, combined with the quasi-two-dimensional binding
energy of field-localized excitons.Comment: 5 pages, 4 figures, submitted to PR
Glass silicate from Cr and Ni high level galvanic waste
[ES] La eliminación de los residuos industriales tóxicos, es en la actualidad un objetivo prioritario a nivel mundial. Para el
caso particular de los residuos sólidos galvánicos, su alto contenido en metales pesados resulta perjudicial tanto para la
salud como para el medio ambiente. En este trabajo se han obtenido vídrios con un 40% en peso de residuos galvánicos
de alto contenido en cromo y níquel. La estabilidad química de los vídrios obtenidos fue comprobada mediante ensayos
de resistencia al ataque hidrolítico, ácido y alcalino. Finalmente, los diferentes vídrios fueron caracterizados por diferentes
técnicas difración de rayos-X, fluorescencia de rayos-X, espectrometría infrarroja.[EN] The environmental and human health related with harmful industrial waste is nowadays an issue of worldwide great
concern. Particularly the case of galvanic solid waste, because of its high content in heavy metals, it is highly harmful from
both environmental and human health point of view. In this study, glasses containing up to 40 wt% of galvanic waste with
a high content of chromium and nickel were obtained. The chemical stability of these glasses was studied by hydrolytic,
alkaline and acid attack. Finally the different glasses were studied by X-ray diffraction, X-ray fluorescence and infrared
spectroscopy techniques in order to rationalize and to understand its observed chemical stability.Peer reviewe
What understanding of the conceptualizations of the limit concept is reached by prospective high school math teachers?
Trends in Cosmetics: Product Packaging at the Point of Sale
Recently, there has been a proliferation of establishments where cosmetics products are packaged at the purchaser’s request, promoting the circular economy with the aim of reusing, recycling and reducing packaging. At the Spanish Agency of Medicines and Medical Devices (AEMPS, for its Spanish acronym), we asked ourselves whether this was a legal and safe practice. In order to verify this, a bibliographic analysis of the applicable legislation and regulations was carried out, and the conclusion reached was that it is legal practice, but a series of guidelines are necessary for it to be carried out with guarantees. Consequently, an instruction was developed which provides recommendations to ensure that the packaging of cosmetic products at the point of sale is carried out under optimum conditions. This instruction is aimed at both responsible persons and the personnel who carry out product packaging at the point of sale
Electrical discharge machining of ceramic/semiconductor/metal nanocomposites
Electroconductive, homogeneous and dense ceramic/semiconductor/metal nanocomposites were obtained by hot pressing and subsequently machined by wire electrical discharge machining (EDM). The addition of semiconductor and metal phases to a high-performance ceramic material produces nanocomposites which preserve the excellent mechanical properties of the ceramic/metal material while possessing the electrical conductivity necessary for EDM. The role of the low concentration of metal has been investigated from a mechanical and an electrical point of view, and found to be critical to the final behavior.This research was supported by the European
Union under the IP-NANOKER project (FP6-515784-
2), by the Spanish Ministry of Education and Science
under the project MAT2006-10249-C02-01.Peer reviewe
Trends in Cosmetics: Product Packaging at the Point of Sale
Recently, there has been a proliferation of establishments where cosmetics products are packaged at the purchaser’s request, promoting the circular economy with the aim of reusing, recycling and reducing packaging. At the Spanish Agency of Medicines and Medical Devices (AEMPS, for its Spanish acronym), we asked ourselves whether this was a legal and safe practice. In order to verify this, a bibliographic analysis of the applicable legislation and regulations was carried out, and the conclusion reached was that it is legal practice, but a series of guidelines are necessary for it to be carried out with guarantees. Consequently, an instruction was developed which provides recommendations to ensure that the packaging of cosmetic products at the point of sale is carried out under optimum conditions. This instruction is aimed at both responsible persons and the personnel who carry out product packaging at the point of sale
Método de obtención de un material compuesto nanoestructurado de matriz cerámica y mecanizable por electroerosión, y producto obtenible por dicho método
Método de obtención de un material compuesto nanoestructurado
de matriz cerámica y mecanizable por electroerosión,
y producto obtenible por dicho método.
Permite obtener un material compuesto cerámica/semiconductor/
metal nanoestructurado y mecanizable por
electroerosión (EDM). Se utilizan como materiales de partida:
un material cerámico de tamaño de partícula nanométrico,
un material semiconductor de tamaño de partícula
nanométrico, y una sal metálica, empleada como precursor
del correspondiente metal. El método comprende
las etapas de: a) preparación de un material en polvo de
cerámica/óxido metálico mediante calcinación de un polvo
seco obtenido a partir de una suspensión homogénea
del material cerámico y la sal metálica precursora de metal;
b) adición al polvo resultante de la etapa anterior del
material semiconductor; c) molienda, homogeneización,
secado y tamizado del polvo resultante de la etapa anterior;
d) tratamiento térmico en atmósfera reductora del
polvo resultante de la etapa anterior, y e) conformado y
sinterizado del polvo de la etapa anterior.Peer reviewedConsejo Superior de Investigaciones Científicas (España)A1 Solicitud de patentes con informe sobre el estado de la técnic
Wet processing and characterization of ZrO2/stainless steel composites: electrical and mechanical perfomance
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