Search results for "Dame"
showing 10 items of 1466 documents
EPR investigations of polymeric and H2O2 -modified C3N4 -based photocatalysts
2019
The C3N4 -based nanopowders prepared by thermal condensation of melamine (MCN) with subsequent thermal etching (MCN-TE) and H2O2 -treatment were investigated by Q- and X-band EPR spectroscopy in dark and upon in situ UVA or visible-light exposure. Lorentzian signal at g = 2.003, more pronounced in the case of the thermally etched material, dominates EPR spectra of MCN and MCN-TE. More complex spectra were found for H2O2 -treated photocatalysts revealing the presence of signals attributed to the radicals produced via H2O2 interaction with C/N sites in the C3N4 polymeric network. The X-band spectra monitored upon in situ irradiation of the C3N4 -based photocatalysts evidenced the intensity gr…
Overview on photoreforming of biomass aqueous solutions to generate H2 in the presence of g-C3N4 based materials
2023
Photoreforming (PR) of biomass can be considered a viable technology under mild experimental conditions to produce hydrogen with a high reaction rate using compounds from renewable resources and waste materials. The application of biomass PR gives rise to both hydrogen generation and biomass waste valorization. The process could be scaled up to obtain hydrogen under natural sunlight irradiation, and research on polymeric carbon nitride (g-C3N4)-based photocatalysts has been widely carried out in recent years. The non-metallic-based carbon nitride materials are economical and (photo)stable polymer semiconductors, and their physicochemical surface and electronic properties are optimal for obt…
El Derecho De La Uniin Europea Ante La Encrucijada Del Impuesto Sobre Sucesiones Y Donaciones Espaaol (EU Law Before the Crossroad of the Spanish Inh…
2014
Spanish Abstract: El articulo analiza los efectos del Derecho de la Union Europea y las libertades fundamentales sobre el impuesto sobre sucesiones y donaciones espanol, teniendo en cuenta las implicaciones y complejas relaciones que derivan de su formulacion como impuesto estatal que ha sido parcialmente cedido a las Comunidades Autonomas. El articulo analiza la posible evolucion tras la sentencia del TJUE de 3 de septiembre de 2014 (asunto C-127/12). El autor critica la argumentacion pobre del TJUE y propone un desarrollo mas consistente del contenido de las libertades fundamentales a partir de un analisis mas solido de los juicios de comparabilidad y de justificacion. El autor tambien cr…
The Longitudinal Associations of Fitness and Motor Skills with Academic Achievement
2019
Supplemental digital content is available in the text.
Gestion du personnel par algorithmes et droits du salarié
2019
International audience
Photocatalysis: Applications
2016
Heterogeneous photocatalysis is a sustainable technology mainly employed for water and air cleaning purposes. However, in the last two decades a lot of attention has been given to photocatalysis as an alternative route to be used in place of traditional industrial processes. The sustainability of photocatalysis mainly comes from the exploitation of renewable sources, such as solar light, and the possibility to avoid unsafe reagents/solvents and severe temperatures and pressures. In this chapter we give a critical presentation of some case studies concerning the use of heterogeneous photocatalysts, such as modified and bare TiO2, ZnO, ZnS, WO3, titanium silicalite, V2O5, polyoxometalates, Cd…
Photocatalytic glucose conversion to produce hydrogen in the presence of TiO2 based materials.
2015
In the present research commercial anatase (BDH) and anatase/rutile (P25) and home prepared anatase (HPA), rutile (HPR) and brookite (HPB) TiO2 polymorphs and have been used as supports for the deposition of metallic Pt. The Pt-TiO2 samples have been tested in the glucose conversion under anaerobic conditions. The presence of Pt resulted essential for the production of H2 and the home prepared samples resulted more active than the commercial ones.
Keggin heteropolyacid supported on TiO2 used in gas-solid (photo)catalytic propene hydration and in liquid-solid photocatalytic glycerol dehydration
2017
Abstract (Photo)catalytic propene hydration to 2-propanol and glycerol dehydration to acrolein were carried out by using Keggin heteropolyacids (HPAs) supported on TiO 2 . Binary materials have been prepared by impregnation of H 3 PW 12 O 40 , H 3 PMo 12 O 40 and H 4 SiW 12 O 40 , on TiO 2 Evonik P25. Moreover, a binary material consisting of H 4 SiW 12 O 40 and TiO 2 was prepared via a hydrothermal treatment and tested for the same reactions. All the materials were characterized by X-ray diffraction (XRD), scanning electron microscopy observations (SEM) coupled with energy dispersive X-ray (EDX) measurements, diffuse reflectance spectroscopy (DRS), Raman spectroscopy and Fourier transform …
Graphical THD minimization procedure for single phase five-level converters
2017
This paper proposes two graphycal procedure to mitigate h harmonics and to minimize the total harmonic distortion (THD), respectively. The paper considers a five-level inverter and fundamental frequency modulation: it computes the two switching angles able to reduce low order harmonics and able to minimize the THD. Simulation results are obtained and, in order to validate the proposed procedure, an experimental prototype is built and experimental results are carried out. The comparison between simulation and experimental results confirms the accuracy of the proposed graphycal procedure. It is shown that the switching angles to mitigate the third-fifth and the third-fifth-seventh harmonics e…
Photocatalytic Processes in Membrane Reactors
2010
Conversion and degradation processes of various substrates in various types of matrices using both artificial and solar light are today very attractive by considering the scarcity and the expensiveness of the conventional energy sources. Coupling of membrane with light has shown to be very powerful and promising hybrid process, especially because a synergistic effect has been often observed. Some examples of reactions carried out to produce useful chemicals or to degrade noxious species in the framework of the green chemistry approach are reported. Fundamentals of heterogeneous photocatalysis, in general, and photocatalytic reactions in membrane reactors, in particular, are treated with a f…