Il progetto idrogeno del comune di Isera

2009-03-26Sala anfiteatro, Via Roma 253, CagliariVerso l'idrogeno. Convegno divulgativo sulle iniziative per la diffusione delle tecnologie dell’idrogeno in Itali

Novel system for distributed energy generation from a small scale concentrated solar power

The present work describes the realization of a modular 1-3 kWe, 3-9 kWth micro Combined Heat and Power (m-CHP) system based on innovative Concentrated Solar Power (CSP) and Stirling engine technology. The cogeneration of energy at distributed level is one of leading argument in large part of energy policies related to renewable energy resources and systems. This CSP m-CHP will provide electrical power, heating and cooling for single and multiple domestic dwellings and other small buildings. The developed system integrates small-scale concentrator optics with moving and tracking components, solar absorbers in the form of evacuated tube collectors, a heat transfer fluid, a Stirling engine with generator, and heating and/or cooling systems; it incorporates them into buildings in an architecturally acceptable manner, with low visual impact. Some good results have already been achieved, while developments on several technology subcomponents will be finalized through first part of 2013. Two Cer.Met. have been modelled, realized and tested. The up scaled receiver, in form of Cer.Met. coating based on TiO2 - Nb, has been confirmed an absorptance of 0.94 and emittance of 0.1 (@350°C). A second Cer.Met. coating based on SiO2 - W has demonstrated an absorptance of 0.93 and emittance of 0.09 (@350°C). A full-evacuated solar tube has been designed and realized, with absorber of 12 mm in diameter and length in 2 meters. The system is provided of a concentration ratio 12:1, and a single module is 200 cm long, 40 cm wide and 20-25 cm high. Two or more modules can be combined. The evacuated solar tube, located on the focus, has the selective absorber on a tube of 12 mm in diameter. A very thin glass mirror has been developed (< 1 mm). The overall mirror reflectivity has been measured, the verified value is 0,954. Research has proposed a high energy density, double acting Stirling engine, provided of innovative heat exchangers realized through Selective Laser Melting process. The engine is a low speed (250 RPM), high pressure (130 Bars) and compact solution able to be run at 300°C and generate 3,5 kW nominal power. The solar technology has actually entered the proof-of-concept stage. A solar plant has been installed in Malta, by Arrow Pharm company, supplying the industrial process of generated steam at 180°C and 3.5 absolute pressure. The solar collector's efficiency is close to 47% in presence of 900 W/m2 of direct solar radiation. During 2013, solar evacuated tubes with innovative Cer.Met. coating, together with new thin glass mirrors will upgrade the demonstration site, together with a new and innovative low temperature difference and high energy density Stirling. By end-2013, the system will be demonstrated, with the overall objective to achieve a minimum of 65% in solar collectors' efficiency at 300°C, and 12 - 15% of overall electrical efficiency by the Stirling cycle.peer-reviewe

Reply to T.P. Vassilakopoulos et al

Lettera di risposta all'articolo "Long-term results of the HD2000 trial comparing ABVD versus BEACOPP versus COPP-EBV-CAD in untreated patients with advanced hodgkin lymphoma: A study by fondazione Italiana Linfomi" pubblicato sulla medesima rivist

Drag-model sensitivity of Kelvin-Helmholtz waves in canopy flows

Two models of the flow over and through an immersed, vegetated layer are examined to study the onset of instability waves across the layer and to assess the effect of mild variations in the mean flow and in the drag force exerted by the canopy onto the frequency and growth rate of the monami instability. One of the two models, based on the use of Darcy’s equation, with a tensorial permeability, within the canopy is more robust than the other (which uses a scalar drag coefficient), i.e., it is less sensitive to the inevitable imperfections or approximations in the input data

Effects of porosity and inertia on the apparent permeability tensor in fibrous media

The flow in three-dimensional fibrous porous media is studied in the inertial regime by first simulating for the motion in unit, periodic cells, and then solving successive closure problems leading – after applying an intrinsic averaging procedure – to the components of the apparent permeability tensor. The parameters varied include the orientation of the driving pressure gradient, its magnitude (which permits to define a microscopic Reynolds number), and the porosity of the medium. All cases tested refer to situations for which the microscopic flow is steady. When the driving force is oriented in a direction whichlies on the plane perpendicular to the fibers’ axis, the results found agree with those available the literature. The fact that the medium is composed by bundles of parallel fibers favours a deviation of the mean flow towards the fibers’ axis when the driving pressure gradient has even a small component along it, and this is enhanced by a decreasing porosity; this phenomenon is well quantified by the knowledge of the components of the permeability. Contrary to our initial expectations, for the over one hundred cases which we have simulated, the apparent permeability tensor remains, to a very good approximation, diagonal, a fact mainly related to the transversely isotropic nature of the medium. To obtain a complete,albeit approximate, database of the diagonal components of the apparent permeability tensor we have developed a metamodel, based on kriging interpolation, and carefully calibrated it. The resulting response surfaces can be invaluable in determining the force caused by the presence of inclusions in macroscopic simulations of the flow through bundles of fibers whose orientations and dimensions can vary in space and/or time

Anthracyclines: a cornerstone in the management of non-Hodgkin's lymphoma

Since anthracyclines were introduced in the treatment of non-Hodgkin's lymphoma in the late 1960s, they have been acknowledged as a cornerstone in the management of the disease and, in particular, of aggressive lymphomas. The high efficacy of anthracycline-containing regimens must, however, be balanced against the drug-related toxicity, which mainly affects the cardiovascular system and represents a major concern for clinicians, especially in the treatment of elderly patients. Patients' outcomes could be further improved, particularly for those at high risk of cardiotoxicity, by substituting liposomal doxorubicin for conventional doxorubicin. This approach has already been tested and shown to be effective in several cancers, especially in different subsets of patients with diffuse large B-cell lymphoma. The use of liposomal doxorubicin in combination regimens for other conditions, such as follicular lymphoma and splenic marginal zone lymphoma, is also under investigation, and early results are promising

Follicular Lymphoma - treatment and prognostic factors.

Follicular lymphoma is the second most frequent non-Hodgkin lymphoma accounting for about 10-20% of all lymphomas in western countries. The median age at diagnosis is 60 years old. The clinical presentation is usually characterized by asymptomatic peripheral adenopathy in cervical, axillary, inguinal and femoral regions. Treatment options for patients with naive or recurrent follicular lymphoma are still controversial, ranging from a "watch and wait" policy to hematopoietic stem cell transplantation. More recently, the availability of rituximab has substantially changed follicular lymphoma therapeutic approaches to such an extent that R-Chemo is now the standard induction first-line treatment. This review provides a general overview of the state of the art in the management of follicular lymphoma and also, a brief description regarding the the current prognostic tools available for treatment decisions

A penalization method to treat the interface between a free-fluid region and a fibrous porous medium

The coupling between the flow through a fibrous porous medium and that in a free-fluid region is studied. The flow dynamics inside the porous medium are described using the volume averaging method applied to the incompressible Navier−Stokes equations in the laminar regime. The two different flow domains are coupled via a penalization method that consists of varying the porous medium properties (porosity and permeability) continuously across the interface. This approach permits the use of the same set of the equations throughout the whole domain. The averaging method is validated against simulations which fully account for the presence of cylindrical fibers positioned at the bottom wall of a square driven cavity. Numerical experiments are carried out for two different Reynolds numbers, large enough to ensure that inertial effects inside the porous domain are not negligible. Good agreement is found when comparing the two approaches