1,636 research outputs found
Orthogonal basis with a conicoid first mode for shape specification of optical surfaces: Reply
We present some comments to the paper “Orthogonal basis with a conicoid first mode for shape specification of optical surfaces: comment.
Regional surface temperature simulations over the Iberian Peninsula: evaluation and climate projections
The realism of a specifc confguration of the WRF Regional Climate Model (RCM) to represent the observed temperature evolution over the Iberian Peninsula (IP) in the 1971–2005 period has been analyzed. The E-OBS observational dataset was used for this purpose. Also, the added value of the WRF simulations with respect to the IPSL Earth System Model (ESM) used to drive the WRF RCM was evaluated. In general, WRF presents lower temperatures than in the observations (negative biases) over the IP. These biases are comparatively larger than those of the driving ESM. Once the biases are corrected, WRF provides an added value in terms of a higher spatial representation. WRF introduces more variability in some regions in comparison to gridded observation. Warming trends according to the observations are also well represented by the RCM. In the second part of this study, the projections of future climate performed with both the ESM and the RCM were evaluated for the RCP4.5 and RCP8.5 scenarios during the 21st century. Although both models simulate temperature increases, the RCM simulates a smaller warming than the ESM after the mid-21st century, except for winter. Using the WRF model, the maximum temperature increase reaches 6 ◦C and 3 ◦C for RCP8.5 and RCP4.5 in the south east of the Iberian Peninsula by the end of the 21st century, respectively
Módulo para la enseñanza de la energÃa solar como una propuesta interdisciplinar para la enseñanza de las ciencias en niveles de educación básica y media en Colombia.
In this paper we present an analysis of results obtained with a didactic proposal based on a module for teaching solar energy concepts in basic and high school levels in Colombia. First, the importance of teaching topics related to solar energy in the school is highlighted, then a brief explanation of the content of this module is made and finally an analysis of results obtained after presenting and testing the proposal with classmates.En el presente documento se hace un análisis de los resultados obtenidos con la propuesta del módulo didáctico para la enseñanza de la energÃa solar en niveles de educación básica y media en Colombia. Primero se resalta la importancia de enseñar temas relacionados con la energÃa solar en la escuela, luego se hace una breve explicación del contenido de este módulo y finalmente se hace un análisis de resultados obtenidos después de presentar y poner a prueba la propuesta con los compañeros de clase
Electronic Properties and Magnetic Moment Distribution on Perovskite Type Slabs: Sr2FeMoO6, SrFeO3 and SrMoO3
AbstractPerovskite type slabs were excised from the Sr2FeMoO6, SrFeO3 and SrMoO3 bulk double perovskites, respectively, leaving (001) free surfaces. Supercells were built up for each slab, keeping a 10Å initial free space, to optimize the geometry. Once the minimum energy state was identified, the electronic and magnetic properties of the [001] oriented slabs have been calculated within the Density Functional Theory (DFT) scheme, with the Hubbard-corrected Local Density Approximation (LDA+U) and the CA−PZ functional. Magnetic moment for each atom in the systems was calculated; spin values for the Mo atoms are –0.02ħ, − 0.13ħ and 0.56ħ for the SrMoO3 slab system case and they are aligned antiferromagnetically. Contrarily, Mo magnetic moments in the Sr2FeMoO3 slab system align antiferromagnetically to the corresponding Fe atoms, being around 10% in magnitude; meanwhile, Fe moments increase and align ferromagnetically in SrFeO3. The Densities of States (DOS) and band structures were calculated also to study the electronic behaviors. The vacuum region changes from the initial 10Å, as geometry stabilizes for all the slab cases; however, slab images separation evolves notoriously different for each model
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