Search results for " confine"
showing 10 items of 115 documents
Lo spazio poetico del confine
2017
Il paesaggio siciliano esprime in sé tutte le contraddizioni del tempo presente. La mancanza di una vera cultura della conservazione e di un pensiero coerente sulla trasformazione dei luoghi ha contribuito, negli ultimi anni, a far crescere il degrado dei centri minori, ha quasi ovunque privato la campagna di una chiara elaborazione estetica. Questa condizione di degrado attraversa in generale l’intero territorio italiano. L’architettura può svolgere un ruolo fondamentale nella ricostruzione di una coerenza nei luoghi, ricercando il senso compiuto del paesaggio, svelando la bellezza latente dei luoghi. Può trasformare i confini (dispersi nel territorio come soluzioni di continuità straniant…
Efficient generation of energetic ions in multi-ion plasmas by radio-frequency heating
2017
We describe a new technique for the efficient generation of high-energy ions with electromagnetic ion cyclotron waves in multi-ion plasmas. The discussed ‘three-ion’ scenarios are especially suited for strong wave absorption by a very low number of resonant ions. To observe this effect, the plasma composition has to be properly adjusted, as prescribed by theory. We demonstrate the potential of the method on the world-largest plasma magnetic confinement device, JET (Joint European Torus, Culham, UK), and the high-magnetic-field tokamak Alcator C-Mod (Cambridge, USA). The obtained results demonstrate efficient acceleration of 3He ions to high energies in dedicated hydrogen–deuterium mixtures.…
Experimental Investigation on the Compressive Behaviour of Clay Brick Masonry Columns Confined by BFRP or Steel Wires
2016
This paper presents the results of an experimental research aiming to investigate on the compressive behavior of full size clay brick masonry columns reinforced with Basalt Fiber Reinforced Cementitious Matrix (BFRCM) or with steel wires collaring. Uniaxial compressive tests were performed on eight retrofitted columns and four control specimens. Two masonry strength were considered by varying the mortar grade. Results are presented and discussed in terms of axial stress-strain relationships, failure modes and crack patterns of the specimens tested up to failure. For the limit of investigated variables, comparisons with unreinforced specimens show the ability of these alternative techniques …
The effect of soil volume on the growth of roots and canopy of Opuntia ficus-indica
2019
The influence of soil volume on root development and canopy growth rates of cactus pear (Opuntia ficus-indica) was studied at Palermo University, Italy, in 2014-2016. In November 2014, 60 1-year-old O. ficus-indica cladodes were planted in pots containing five different soil volumes, 50, 33, 18, 9 or 5 L, in a complete randomized design with three replications. Root dry mass, total number of cladodes and canopy dry mass were measured after 6, 12, 18 and 24 months. The results revealed a significant effect of soil volume and sampling time and their interaction (P<0.01) on root dry mass, total number of cladodes and canopy dry mass. Root dry mass ranged between 23 and 206 g, with the highe…
Analisi Sperimentale del Comportamento Ciclico di Elementi in Calcestruzzo a Bassa Resistenza Confinati con FRCM
2013
Vengono riportati i principali risultati di una campagna sperimentale finalizzata alla caratterizzazione della risposta sotto carichi assiali ciclici di colonne di calcestruzzo a bassa resistenza con sezione circolare, quadrata e rettangolare, rinforzate con fibre di carbonio immerse in matrice cementizia (CFRCM). Sono state condotte prove di compressione assiale su 30 campioni di altezza 600 mm, 10 a sezione cilindrica di diametro 300 mm, 10 quadrata di lato 200 mm, e 10 rettangolare di lato 200x400 mm. Le prove sono finalizzate a indagare gli effetti del carico ciclico, della forma della sezione, del raggio di curvatura degli spigoli e del numero di strati di tessuto di rinforzo sul legam…
Experimental results of RC columns strengthnened with Fiber Reinforced Cementitious Mortars
2012
The structural behaviour of reinforced concrete columns strengthened with a system made up of fibre nets embedded in an inorganic stabilized cementitious matrix was investigated. Specimens with circular and square cross-section were cast and subjected to monotonic uniaxial compression to investigate the efficiency of a Polypara-phenylene-benzo-bisthiazole (PBO) Fibre Reinforced Cementitious Mortars (FRCM) system in increasing both carrying capacity and ductility. The experimental results show that confinement with PBO fibre produced a noticeable increment in strength and ductility, though the low mechanical ratios of fibre considered were not always able to ensure hardening behaviour up to …
Overview of the JET results
2015
Since the installation of an ITER-like wall, the JET programme has focused on the consolidation of ITER design choices and the preparation for ITER operation, with a specific emphasis given to the bulk tungsten melt experiment, which has been crucial for the final decision on the material choice for the day-one tungsten divertor in ITER. Integrated scenarios have been progressed with the re-establishment of long-pulse, high-confinement H-modes by optimizing the magnetic configuration and the use of ICRH to avoid tungsten impurity accumulation. Stationary discharges with detached divertor conditions and small edge localized modes have been demonstrated by nitrogen seeding. The differences in…
Induced Chirality in Confined Space on Halogen Gold Complexes
2015
The solubilization of HAuCl4 in toluene within optically active reverse micelles and lamellar structures formed by (1R,2S)-Dodecyl(2-hydroxy-1-methyl-2-phenylethyl)- dimethylammonium bromide (DMEB) has allowed us to evidence the complex phenomenology accompanying the confinement of Au salt within these nanostructures. Together with a chloride/bromide exchange process occurring in the first coordination sphere of an Au ion, UV−vis and electronic circular dichroism (ECD) spectra reveal the appearance of an induced dichroic signal attributable to Au complexes entrapped in the hydrophilic domain of the DMEB chiral nanostructures. Interestingly, change of the effective oxidation state and coordi…
Stress-Strain Law for Confined Concrete with Hardening or Softening Behavior
2013
This paper provides a new general stress-strain law for concrete confined by steel, fiber reinforced polymer (FRP), or fiber reinforced cementitious matrix (FRCM), obtained by a suitable modification of the well-known Sargin’s curve for steel confined concrete. The proposed law is able to reproduce stress-strain curve of any shape, having both hardening or softening behavior, by using a single closed-form simple algebraic expression with constant coefficients. The coefficients are defined on the basis of the stress and the tangent modulus of the confined concrete in three characteristic points of the curve, thus being related to physical meaningful parameters. It will be shown that if the v…
A three-dimensional study of the onset of convection in a horizontal, rectangular porous channel heated from below
2012
Author's version of an article published in the journal: International Journal of Thermal Sciences. Also available from the publisher at: http://dx.doi.org/10.1016/j.ijthermalsci.2011.12.012 The onset of convection is studied in a rectangular channel filled with a fluid saturated porous medium, bounded above and below by impermeable isothermal walls at unequal temperatures and laterally by partially conducting walls. A three-dimensional linear stability analysis is carried out under the assumption of an infinite longitudinal channel length. Then, this assumption is relaxed in order to determine the threshold length for the three-dimensional convection to be the preferred mode at onset. Sens…