Este artículo pretende describir el uso y las implicaciones de las tecnologías de telecomunicación en la enseñanza a distancia norteamericana. Se ofrece un descripción de la oferta y la demanda de la programación por satélite y cable, las posibles causas del aumento de cursos a distancia en universidades y los contenidos de algunos programas,...
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September 26, 2016 (v1)PublicationUploaded on: March 27, 2023
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September 26, 2016 (v1)Publication
En los últimos años, la Internet ha experimentado un crecimiento espectacular y los responsables de la educación de los países desarrollados preconizan su incorporación a todos los niveles de enseñanza. Este articulo propone una reflexión sobre la Internet desde perspectivas que incluyen el análisis de sus implicaciones socioeconómicas y la...
Uploaded on: December 5, 2022 -
March 6, 2019 (v1)Publication
The oblique angle configuration has emerged as an invaluable tool for the deposition of nanostructured thin films. This review develops an up to date description of its principles, including the atomistic mechanisms governing film growth and nanostructuration possibilities, as well as a comprehensive description of the applications benefiting...
Uploaded on: December 4, 2022 -
April 5, 2018 (v1)Publication
This study shows that Ostwald ripening, a universal mechanism responsible for the increase of crystal size during precipitation from solutions, can be meditated by ion diffusion through condensed monolayers of water that connect separated nanocrystals. In an environmental electron microscope we have observed "in situ" the time evolution of the...
Uploaded on: December 4, 2022 -
January 16, 2023 (v1)Publication
The growth of TiO₂ and ZnO thin films is studied by means of coarse-grained kinetic Monte Carlo simulations under conditions typically encountered in plasma-enhanced chemical vapor deposition experiments. The basis of our approach is known to work well to simulate the growth of amorphous materials using cubic grids and is extended here to...
Uploaded on: March 3, 2023 -
November 13, 2015 (v1)Publication
were deposited on flat substrates by physical vapor deposition in a glancing angle configuration. The particles were characterized by scanning electron microscopy and atomic force microscopy and their optical properties examined by UV–vis absorption spectroscopy using linearly polarized light. It was found that, depending on the amount of...
Uploaded on: December 4, 2022 -
November 19, 2015 (v1)Publication
This work reports the low temperature plasma formation of Ag@TiO2 nanorods (NRs) on processable substrates. The layers have been analyzed by electron microscopy and secondary ion mass spectroscopy. The NRs morphologies suggest that the plasma sheath, the high mobility of the silver and the incoming direction of the precursor moieties are key...
Uploaded on: March 27, 2023 -
May 7, 2018 (v1)Publication
This work reports the morphological and chemical modifications induced in TiO2 thin films by bombardment with high energy N+ ions at different temperatures and their different photo-activity responses after implantation under visible and UV light illumination. When implanted samples are illuminated with visible light, no dye photo-decolouration...
Uploaded on: March 27, 2023 -
January 13, 2022 (v1)Publication
Switchable mechanically induced changes in the wetting behavior of surfaces are of para-mount importance for advanced microfluidic, self‐cleaning and biomedical applications. In this work we show that the well‐known polydimethylsiloxane (PDMS) elastomer develops self‐patterning when it is coated with nanostructured TiO2 films prepared by...
Uploaded on: December 5, 2022 -
November 23, 2015 (v1)Publication
Ta2O5 thin films with different nanostructure and surface roughness have been prepared by electron evaporation at different angles between the evaporation source and the substrates. Large variation of refraction indexes (n) from 1.40 to 1.80 were obtained by changing the geometry of evaporation and/or by annealing the evaporated films at...
Uploaded on: March 24, 2023 -
October 13, 2022 (v1)Publication
Fabrication of tunable wetting surfaces is sought for the last years given its importance on energy, biomaterials and antimicrobials, water purification, microfluidics, and smart surfaces. Liquid management on surfaces mainly depends on the control at the micro- and nanoscale of both roughness and chemical composition. Herein, the combination...
Uploaded on: March 24, 2023 -
February 5, 2024 (v1)Publication
This work reports about the preparation of plasma polymerized thin films of perylene with thicknesses ∼30−150 nm and their characterization by different methods and the analysis of their optical properties. Highly absorbent and fluorescent films have been obtained by this method that combines the sublimation of the perylene molecules and their...
Uploaded on: February 7, 2024 -
May 2, 2023 (v1)Publication
Two-dimensional materials present exceptional crystal elasticity and provide an ideal platform to tune electrical and optical properties through the application of strain. Here we extend recent research on strain engineering in monolayer molybdenum disulfide using an adamantane plasma polymer pinning layer to achieve unprecedented crystal...
Uploaded on: May 4, 2023 -
November 19, 2015 (v1)Publication
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Uploaded on: March 27, 2023 -
April 9, 2018 (v1)Publication
A three-step vacuum procedure for the fabrication of vertical TiO2 and ZnO nanotubes with three dimensional walls is presented. The method combines physical vapor deposition of small-molecules, plasma enhanced chemical vapor deposition of inorganic functional thin films and layers and a postannealing process in vacuum in order to remove the...
Uploaded on: March 27, 2023 -
April 24, 2018 (v1)Publication
Luminescent organic-thin-films transparent in the visible region have been synthesized by a plasma assisted vacuum deposition method. The films have been developed for their implementation in photonic devices and for UV detection. They consist of a plasma polymeric matrix that incorporates 3-hydroxyflavone molecules characterized by absorption...
Uploaded on: December 4, 2022 -
January 25, 2019 (v1)Publication
In this article we present a new type of 1D nanostructures consisting of supported hollow ZnO nanorods (NRs) decorated with Ag nanoparticles (NPs). The 3D reconstruction by high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) electron tomography reveals that the Ag NPs are distributed along the hollow interior of...
Uploaded on: December 4, 2022 -
November 13, 2015 (v1)Publication
ITO thin films have been prepared by electron beam evaporation at oblique angles (OA), directly and while assisting their growth with a downstream plasma. The films microstructure, characterized by scanning electron microscopy, atomic force microscopy and glancing incidence small angle X-ray scattering, consisted of tilted and separated...
Uploaded on: March 24, 2023 -
March 22, 2018 (v1)Publication
This paper addresses the fabrication of vertically aligned ZnO@TiO2 multishell nanotubes by a combined full vacuum-plasma approach at mild temperatures. The growth is carried out within the premises of a one-reactor approach, i.e. minimizing the number of vacuum chambers and sample transferences. In this way, the interface between ZnO and TiO2...
Uploaded on: March 27, 2023 -
September 1, 2022 (v1)Publication
The opto-electronic properties of small-molecules and functional dyes usually differ when incorporated into solid matrices with respect to their isolated form due to an aggregation phenomenon that alters their optical and fluorescent properties. These spectroscopic modifications are studied in the framework of the exciton theory of aggregates,...
Uploaded on: December 2, 2022 -
November 13, 2015 (v1)Publication
We present a straightforward procedure of self-surface patterning with potential applications as large area gratings, invisible labeling, optomechanical transducers, or smart windows. The methodology is based in the formation of parallel micrometric crack patterns when polydimethylsiloxane foils coated with tilted nanocolumnar SiO2 thin films...
Uploaded on: March 27, 2023