3,770 research outputs found
Inflatable traversing probe seal
An inflatable seal acts as a pressure-tight zipper to provide traversing capability for instrumentation rakes and probes. A specially designed probe segment with a teardrop cross-section in the vicinity of the inflatable seal minimizes leakage at the interface. The probe is able to travel through a lengthwise slot in a pressure vessel or wind tunnel section, while still maintaining pressure integrity. The design uses two commercially available inflatable seals, opposing each other, to cover the probe slot in a wind tunnel wall. Proof-of-concept tests were conducted at vessel pressures up to 30 psig, with seals inflated to 50 psig, showing no measurable leakage along the seal's length or around the probe teardrop cross-section. This seal concept can replace the existing technology of sliding face plate/O-ring systems in applications where lengthwise space is limited
Probe insertion apparatus with inflatable seal
A sealing apparatus is disclosed for inserting a probe into a pressure vessel having an elongated opening includes a pair of resiliently deformable seals opposingly disposed in sealing engagement with each other. A retainer is connected to the pressure vessel around the elongated opening and holds the pair of seals rigidly to the pressure vessel. A wedge is engageable with the pair of seals and carries the probe, for longitudinally translating the probe in pressure vessel
Fluid-structure interactions of anisotropic thin composite materials for application to sail aerodynamics of a yacht in waves
In recent years technological innovations has allowed large improvements to be made in sail design and construction. Sails and in particular kite-sails have application for sport, ships’ auxiliary propulsion and even power generation. Sails are divided into upwind and downwind sails (Fig.1), where upwind sails operate as lifting surfaces with small angles of attack whereas
traditional downwind sails acted as drag device. New designs of downwind sails have reduced the area of separated flow and increased the lifting behaviour of the sails. In order to capture the lifting behaviour and regions of separation present in both types of sail careful application of computational fluid dynamic analysis tools are required. Solutions of the Reynolds averaged Navier-
Stokes equations (RANSE) are often used as a part of the design process of high performance sailing yachts.The present paper discusses some initial investigations and future guidelines in order to get a more detailed description of the physics involved in sail FSI. Three main fields are therefore covered: the use of CFD in order to accurately capture flow features and a comparison with experimental results; structural modelling; and approach to couplin
Insetti edibili: rischi alimentari e aspetti normativi
La necessità di garantire la sicurezza alimentare ad una popolazione mondiale che, nel 2050, si prospetta di oltre 9 miliardi di persone ha spinto la comunità scientifica a guardare, con crescente interesse, all’impiego degli insetti come fonte di proteine per l’uomo e come mangimi per gli animali.
La complessità e l’enorme quantità di informazioni che deriva dall’analisi della letteratura offre un’utile indicazione circa l’importanza che il tema ha recentemente acquisito in tutti i campi scientifici.
Gli insetti rappresentano una fonte di proteine e grassi piĂą efficiente rispetto agli animali da reddito tradizionalmente allevati, producono meno gas serra e possono essere utilizzati per decomporre i rifiuti.
Il consumo di insetti inoltre non è una novità per l’uomo. La FAO dichiara che gli insetti integrano già la dieta di circa 2 miliardi di persone ed hanno sempre fatto parte dell’alimentazione umana. Sono però necessarie ulteriori ricerche per ottimizzare i sistemi di allevamento e verificare gli eventuali rischi per la salute e il benessere degli uomini e degli animali.
Inoltre la legislazione sull’utilizzo d’insetti, nella maggior parte dei paesi industrializzati, non è adeguata e rappresenta quindi un vincolo. Occorre dunque che vengano approvate norme per la produzione e la trasformazione sicura di prodotti alimentari a base di insetti per consentire di sviluppare allevamenti su piccola e larga scala e poter quindi impiegare gli insetti nell’industria alimentare e mangimistica.
Tuttavia la non predisposizione al consumo di tali risorse in molti paesi occidentali rimane uno dei maggiori ostacoli all'adozione degli insetti come fonti di proteine; tale aspetto necessita di ulteriori ricerche di valutazione socio-economiche per stimare la percezione del consumatore occidentale e fornire una corretta ed efficace informazione ai diversi soggetti coinvolti affinché l’aspetto innovativo possa essere accettato e condiviso.
La sfida per la comunità scientifica nazionale e internazionale è quindi rendere possibile l’aumento della produttività alimentare per mezzo di sistemi alimentari sostenibili, per garantire un’alimentazione sana, sicura, sufficiente e dignitosa per ogni essere umano
Role of aliskiren in blood pressure control and renoprotection
Patients with chronic renal disease are at increased risk for the development of cardiovascular disease, which is the main cause of death in this growing population. Among the risk factors involved, hypertension and proteinuria are major contributors to kidney damage and, if not controlled, may eventually lead to the progression of renal failure and end-stage renal disease. Both proteinuria and hypertension can be primary pathologic events or can appear as complications of other disease processes. Initially, these two factors may operate separately but, as progression ensues, both processes generally combine, potentiating their effects and hastening renal damage. Therefore, strategies to reduce blood pressure and proteinuria are essential in order to slow the worsening of many nephropathies. Therapies that target the renin–angiotensin system offer particular benefit, as hypertension and proteinuria can be precisely reduced with angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers. However, with this intervention, plasma renin activity remains high, and although primary endpoints may be controlled, elevated renin concentration can contribute to cardiovascular damage. Aliskiren, a direct renin inhibitor, is the first example of a novel class of antihypertensive drugs with potent antiproteinuric effects, which, alone or combined, can contribute to delaying the progression of kidney disease
PietĂ e cultura religiosa nella Sicilia del settecento
Pieta e cultura religiosa nella Sicilia del settecent
The impact of Article 41 of the EU Charter of Fundamental Rights on the Italian administrative law: some observations.
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