Search results for "dam"
showing 10 items of 3828 documents
An XRD, TEM and Raman study of experimentally annealed natural monazite
2002
The healing of radiation damage in natural monazite has been experimentally studied in annealing experiments using XRD, TEM, Raman microprobe and cathodoluminescence analysis. The starting material was a chemically homogeneous monazite from a Brazilian pegmatite with a concordant U–Pb age of 474 ± 1 Ma and a U–Th/He age of 479 Ma. The monazite shows nm-scale defects induced by radioactive decay. The Xray pattern of the unheated starting material revealed two distinct monazite ''phases'' A and B with slightly different lattice parameters. Monazite A shows sharp reflections of high amplitudes and slightly expanded lattice parameters (1% in volume) compared to a standard monazite. Phase B exhi…
Sol-gel synthesis and photocatalytic activity of ZnO-SnO2 nanocomposites
2014
Abstract ZnO–SnO 2 nanocomposites were synthesized by a facile sol–gel synthesis route and characterized through X-ray diffraction, BET specific surface area analysis, UV–vis diffuse reflectance spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy. The photocatalytic activity of the samples was tested using the degradation of 4-nitrophenol under UV light as model reaction. The ZnO/SnO 2 molar ratio was varied in order to study its influence on the photoefficiency of the samples. The ZnO–SnO 2 nanocomposites showed higher photoactivity than the pure oxides and in particular the sample with ZnO/SnO 2 mol…
Photocatalytic behaviour of metal-loaded TiO2 aqueous dispersions and films
2007
Abstract Titanium dioxide nanoparticles loaded with Ce, Co, Eu, Sm, W and Yb species were prepared by coprecipitation in mild conditions using TiCl 4 as precursor with the aim to enhance the photocatalytic activity, especially under visible light irradiation. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), specific surface area (SSA) determination and UV–Vis diffuse reflectance spectroscopy. The photocatalytic activity of the powders of pure and loaded TiO 2 was investigated by employing the photodegradation of 4-nitrophenol as probe reaction in a liquid–solid system. Loading with suitable amounts of W, Co and Sm resulted in a significan…
Metal ions modify DNA-protecting and mutagen-scavenging capacities of the AV-153 1,4-dihydropyridine.
2019
Abstract 1,4-Dihydropyridines (1,4-DHP) possess important biochemical and pharmacological properties, including antioxidant and antimutagenic activities. AV-153-Na, an antimutagenic and DNA-repair enhancing compound was shown to interact with DNA by intercalation. Here we studied DNA binding of several AV-153 salts to evaluate the impact of AV-153 modifications on its DNA binding capacity, the ability to scavenge the peroxynitrite, to protect HeLa and B-cells cells against DNA damage. Affinity of the AV-153 salts to DNA measured by a fluorescence assay was dependent on the metal ion forming a salt in position 4 of the 1,4-DHP, and it decreased as follows: Mg > Na > Ca > Li > Rb > K. AV-153-…
Damage and plasticity at the interfaces in composite materials and structures
2009
Abstract The structural behavior at the interface between two surfaces of ductile, brittle or quasi-brittle materials is studied by a new analytical elastoplastic damaging model. The model is developed in the framework of a thermodynamically consistent theory. The Helmholtz free energy is written to predict the materials’ hardening or softening. An isotropic damage is considered and the possible effects of dilatancy are taken into account including non-associative flow rules. The interface laws are presented both in a rate and a discrete incremental form. The analytical formulation is then implemented into a finite element code and two structural members are studied to validate the model. T…
La Guantanamo d'Europa? Il proibizionismo delle migrazioni e la violazone dei diritti fondamentali alla frontiera siciliana.
2009
Conseguenze delle misure di contrasto dell'immigrazione irregolare sui migranti anche con riferimento ai minori ed ai richiedenti asilo
Detention centres: An Unjust and Ineffective Policy
2009
L'articolo riferisce la situazione della detenzione amministrativa dei migranti irregolari in Italia e prospetta il contrasto delle normative e delle prassi amministrative che si riscontrano in questo campo con i principi che tutelano i diritti fondamentali della persona.
La tutela della salute nella giurisprudenza costituzionale del 2010
2010
La giurisprudenza costituzionale del 2010 interviene con diverse pronunce sulla tutela della salute. Gran parte delle decisioni sono state emesse in giudizi di legittimità costituzionale delle leggi in via principale. Soltanto una minima parte è stata resa in giudizi in via incidentale. Come ormai da alcuni anni, la giurisprudenza costituzionale in materia di tutela della salute ha ad oggetto più direttamente le problematiche connesse al riparto di competenze normative fra Stato e Regioni e meno i temi della “struttura” del diritto alla salute; del “contenuto costituzionalmente protetto” di tale diritto; del rapporto fra funzione legislativa e definizione delle modalità di esercizio del dir…
Principio delle pari opportunità e divieto di discriminazioni fondate sull'handicap
2012
Lo scritto affronta il tema della parità di trattamento delle persone con disabilità in una prospettiva di diritto interno e di diritto comunitario, con specifica attenzione ai principi sanciti nella Carta dei diritti fondamentali dell'Unione europea. Ampio spazio è dedicato allo studio delle pari opportunità nello sport, avuto particolare riguardo al Codice europeo di etica sportiva, nonchè ai principi sanciti nel Libro Bianco sullo sport The paper explores the topic theme of equal treatment of persons with disabilities with a view to national law and Community law, with specific attention to the principles enshrined in the Charter of Fundamental Rights of the European Union. Considerable …