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Competencias argumentativas en la alfabetización académica
2011
Este trabajo se enmarca en las numerosas investigaciones sobre escritura académica que vienen desarrollándose en diversos países. Dentro de ellas, buscamos articular líneas de investigación que se ocupan de la alfabetización académica, de los géneros académicos y del papel de la argumentación en los mismos. Para ello, implementamos desde 2005 un programa de alfabetización académica en una asignatura de Humanidades de una universidad argentina, cuyo tramo final es la elaboración y exposición de ponencias grupales, entendidas como construcciones argumentativas que ponen en consideración resultados de investigación. En relación con éstas, este trabajo presenta resultados, en torno a la relació…
De errores y erratas. Cómo corregir y normalizar un texto académico
2012
En el presente artículo, se intenta demostrar en primer lugar, a partir de ejemplos de una revista académica de lingüística, que errores y erratas tienen el mismo protagonismo en la corrección de textos académicos. Pero además, que los criterios y procedimientos de normalización – definida como el conjunto de decisiones y de procedimientos que tienden a unificar el estilo de un escrito en todos sus niveles– son fundamentales para que un conjunto de artículos científicos de autores varios o una serie de trabajos de un mismo autor, de distinto tema o etapas académicas, puedan llegar a convertirse en una publicación periódica o en un libro. In the present article, we first intend to demonstrat…
La forma de gobierno en la Constitución de Cádiz (reflexiones sobre la configuración de la Jefatura del Estado monárquica)
2012
A partir de las circunstancias históricas de las Cortes de Cádiz y de los precedentes de la monarquía española, el artículo analiza la posición de la Jefatura del Estado monárquica en la Constitución de 1812 caracterizada como una «Monarquía moderada» basada en los principios estructurales de soberanía nacional y división de poderes que determinan la configuración del Rey como poder constituido en la nueva forma de gobierno. La afirmación de la soberanía nacional impregna el conjunto del texto constitucional sin perjuicio de que coexista retóricamente con la antigua legitimidad monárquica. Por otra parte, la división de poderes supone la distinción entre la titularidad de la soberanía y su …
Spin filtering by proximity effects at hybridized interfaces in spin-valves with 2D graphene barriers
2020
We report on spin transport in state-of-the-art epitaxial monolayer graphene based 2D-magnetic tunnel junctions (2D-MTJs). In our measurements, supported by ab-initio calculations, the strength of interaction between ferromagnetic electrodes and graphene monolayers is shown to fundamentally control the resulting spin signal. In particular, by switching the graphene/ferromagnet interaction, spin transport reveals magneto-resistance signal MR > 80% in junctions with low resistance × area products. Descriptions based only on a simple K-point filtering picture (i.e. MR increase with the number of layers) are not sufficient to predict the behavior of our devices. We emphasize that hybridization …
Dynamical learning of a photonics quantum-state engineering process
2021
Abstract. Experimental engineering of high-dimensional quantum states is a crucial task for several quantum information protocols. However, a high degree of precision in the characterization of the noisy experimental apparatus is required to apply existing quantum-state engineering protocols. This is often lacking in practical scenarios, affecting the quality of the engineered states. We implement, experimentally, an automated adaptive optimization protocol to engineer photonic orbital angular momentum (OAM) states. The protocol, given a target output state, performs an online estimation of the quality of the currently produced states, relying on output measurement statistics, and determine…
Correlative study of structural and optical properties of ZnSe under severe plastic deformation
2019
The effect of plastic deformation on the optical and structural properties of ZnSe crystals has been investigated. The optical properties have been monitored by cathodoluminescence measurements as a function of the deformation degree. Remarkable differences in the defect-related emissions from the most severely deformed areas have been encountered. Deformation of the crystal lattice of ZnSe, associated with slip phenomena, has been studied by means of Electron Backscattered Diffraction and micro-Raman spectroscopy. The relation between the deformation and the optical properties of the ZnSe crystals has been described.
Superparamagnetic recoverable flowerlike Fe3O4@Bi2O3 core–shell with g-C3N4 sheet nanocomposite: synthesis, characterization, mechanism and kinetic s…
2019
In the present research study, a simple method was developed for the synthesis of three-dimensional flowerlike Fe3O4@Bi2O3 core–shell with g-C3N4 sheet nanocomposites. The X-ray diffraction, Fourier transform infrared spectroscopy, scanning electronic microscopy, transmission electron microscope, vibrating sample magnetometer, dynamic laser scattering analyzer and UV–Vis diffuse reflection spectroscopy were employed for the characterization of structure, purity and morphology of the resultant samples. The degradation of indigo carmine as a model of organic dye pollutant is applied for photo-catalytic activity. The parameters which are affecting the efficiency of various parameters, such as;…
Analysis of 7Be and 210Pb concentration and 7Be/210Pb activity ratio in ground level air in Palermo (Italy)
2019
A series of measurements of particulate samples collected on paper filters in Palermo (Italy) during 1995–2005 has been performed to detect 210Pb air activity concentration and, along with previous similar data on 7Be, to evaluate their activity ratio. Average values for the daily activity concentrations of 7Be and 210Pb are found to be 4.7 and 0.6 mBq/m3 , respectively, 9.8 being the average activity ratio. Data confirm a seasonal behavior for both radionuclides. A correlation between 7Be and 210Pb air activity concentrations seems to exist, despite their different origins. The time behaviors of both 7Be and 210Pb air concentrations and 7Be/ 210Pb activity ratio have been compared with som…
Formation of dibutyl carbonate and butylcarbamate via CO2 insertion in titanium(IV) butoxide and reaction with n-butylamine
2016
Abstract The species resulting from insertion of 12CO2 and 13CO2 into titanium(IV) butoxide is for the first time fully characterized by means of infrared and nuclear magnetic resonance spectroscopy. Results show formation of Ti-monobutylcarbonate, that easily undergoes nucleophilic attack by an aliphatic amine. The hydrolysis of the resulting species produces butylcarbamate and dibutylcarbonate as the only main products. Characterization results of the carbonate-like adduct, along with its reactivity with amine molecules open the route to new ways of CO2 utilization as building block for valuable organic compounds.
One-Pot, Clean Synthesis of Vanillic Acid from Ferulic Acid
2016
Ferulic acid dissolved in water is selectively oxidized to vanillic acid in high yield (≈60 %) under remarkably mild and green conditions, namely at room temperature with air as primary oxidant, over a catalytic amount of nanostructured Bi2WO6. The process is general and opens the route to the selective oxidation of natural substances into derivatives of significant applicative relevance.