Search results for "Solid"

showing 10 items of 3575 documents

Palermo si cura. Pratiche culturali di mutuo soccorso come risposta alle fragilità della città (post)pandemica

2023

In un quadro di riferimento in cui la crisi è globalizzata ma diseguale e in mancanza di un sistema di welfare capace di rispondere alle urgenze dei contesti e dei gruppi sociali più marginalizzati, una risposta ai nuovi bisogni sociali ed individuali è stata offerta da reti solidali e da pratiche di mobilitazione dal basso che svolgono un ruolo di agency territoriale, spesso indipendentemente o in assenza di Istituzioni. Nel contesto palermitano un impegno agito da una pluralità di soggetti culturali già attivi sul territorio, riuniti in un’assemblea pubblica (Palermo si cura), durante il periodo del primo lockdown hanno dato vita ad azioni di mutuo soccorso per rispondere all’emergenza ec…

Settore ICAR/21 - UrbanisticaIn a framework in which the crisis is globalized but unequal and in the absence of a welfare system capable of responding to the urgencies of the most marginalized contexts and social groups a response to the new social and individual needs has been offered by networks of solidarity and from bottom-up mobilization practices that play a role of territorial agency often independently or in the absence of institutions. In the Palermo context a commitment made by a plurality of cultural subjects already active in the area gathered in a public assembly (Palermo si cura) during the period of the first lockdown gave rise to mutual aid actions to respond to the economic emergency and social and offer a proposal to cure the fragility of the city based not on charity but on the claim of a political dimension of collective action. Starting from the analysis of initiatives such as "Un sorriso per Ballarò" and "Abbiamo un (bi)sogno" the contribution analyzes the role the incidence and the fragility of these experiences in providing answers - often filling gaps - to a general interest and how these processes of value creation can hopefully contribute to the construction of local government policies capable of addressing emerging issues.
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Propellant non-steady burning effects on controllable solid rocket motor internal ballistics

2009

An analysis of the unsteady non-linear behavior of the controllable solid propellant rocket motor (CSRM) consequent to rapid and relevant nozzle operation is presented. The study includes a development of a non-linear unsteady combustion model able to handle relevant and rapid chamber pressure changes typical of CSRMs. The CSRM nonlinear unsteady model is implemented according to a main solver - sub models architecture and uses different time scales. The formulation of the combustion gas mass flow rate is developed considering the propellant density, the unsteady combustion, the regression of the combustion surface and the outflow through the variable nozzle. The grain surface involved in t…

Settore ING-IND/07 - Propulsione AerospazialeCONTROLLABLE SOLID ROCKET MOTOR UNSTEADY COMBUSTION
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Life cycle assessment of solid oxide fuel cells and polymer electrolyte membrane fuel cells: A review

2017

Fuel cells (FCs) are among the key technologies that Europe will have to rely on in order to comply with the most recent environmental targets inspired by decarbonization and circular economy. The assessment of the real advantages of using FCs for producing energy must include a reliable analysis of the energy and environmental impacts during the life cycle of these systems, including the raw materials supply, production, use, and disposal. In this context, the life cycle assessment (LCA) is a well-established methodology for assessing the eco-profile of products and services and for identifying the components and the life cycle steps having the largest contribution to energy and environmen…

Settore ING-IND/11 - Fisica Tecnica AmbientalePolymer Electrolyte Fuel CellReviewLife Cycle AssessmentPolymer Electrolyte MembraneSolid Oxide Fuel Cell
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INFLUENCE OF PLASTICIZERS ( OR EXCESS FREE VOLUME ) ON SEMI-CRYSTALLINE POLYESTER BLEND SOLIDIFICATION UNDER PROCESSING CONDITIONS.

2011

Settore ING-IND/22 - Scienza E Tecnologia Dei MaterialiINFLUENCE OF PLASTICIZERS ( OR EXCESS FREE VOLUME )SEMI-CRYSTALLINE POLYESTER BLEND SOLIDIFICATIONPROCESSING CONDITIONS.
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Comparative study between four consolidation systems suitable for archaeological bone artefacts

2015

This study started with the restoration of a 14th century Italian crosier during the final Master year project at the Institute National du Patrimone in Paris (Palazzo 2014). The characterization and consolidation of the bone materials constituting the crosier was needed due to its poor state of conservation. Several products, both organic polymers and inorganic consolidants applied on artificially altered bone material underwent scientific investigations consisting of several analyses and mechanical tests in order to choose the most suitable for the restoration intervention. The results thus obtained showed that both nanolime and a mix of Paraloid® and calcium phosphate seem to be adequate…

Settore ING-IND/22 - Scienza E Tecnologia Dei Materialiarchaeological boneCultural heritageConsolidant test
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Amorphous semiconducting passive film-electrolyte junctions revisited. The influence of a non homogeneous density of state on the differential admitt…

2006

Abstract An analysis of the electronic properties of amorphous semiconductor-electrolyte junction is reported for passive films grown on Nb in alkaline solution and in a large range of thickness (~20nm ÷ ~250nm). A modelling of electronic density of state (DOS) has been carried out by fitting EIS spectra, at different potentials and in a range of frequencies (0.1 Hz ≤ f ≤100 kHz), and differential admittance (DA) data of a-Nb 2 O 5 /El interface. The fitting of EIS and DA curves was performed by using the theory of amorphous semiconductor Schottky barrier and a non-homogeneous DOS distribution.

Settore ING-IND/23 - Chimica Fisica ApplicataAdmittanceMaterials scienceSchottky barrierAnalytical chemistryDensity of statesElectrolyteSpectral linea-SC Schottky barrierAmorphous solidAnodeElectronic density
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Effect of Incorporation of Foreign Species on the Solid State Properties of Anodic Films on Ti

2014

Settore ING-IND/23 - Chimica Fisica ApplicataIncorporation of Foreign Species Solid State Properties Anodic Films on Ti Photoelectrochemistry Electrochemical Impedance Spectroscopy
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Characterization of the Solid State Properties of Anodic Oxides Grown on Sputter-deposited Al-Nb Alloys.

2012

Settore ING-IND/23 - Chimica Fisica ApplicataSolid State Properties Anodic Oxides Al-Nb Alloys
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Solid State Properties of Anodic Hf-Nb Mixed Oxides

2016

In last decades, HfO2 and Nb2O5 have been extensively studied due to their many potential applications, from corrosion protection to CMOS (as high-k gate dielectrics) [1-2] and ReRAM technologies [3-4]. For these technological applications compact, uniform and flat oxides are necessary, and a detailed understanding of their physical properties as a function of the fabrication conditions is needful. Scientific community gradually shifted its interest from pure metal oxides to mixed metal oxides trying to exploit the advantages of pure oxides and to suppress their disadvantages. Mixed oxides can be grown on valve metals alloys by anodizing, a simple and low cost electrochemical process for pr…

Settore ING-IND/23 - Chimica Fisica ApplicataSolid State Properties Anodizing Hf-Nb Mixed Oxides MOS based devices ReRAM technologies
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Tuning of Solid-sate Properties of Al Mixed Oxides Grown on Sputter-deposited Al Alloys.

2012

Settore ING-IND/23 - Chimica Fisica ApplicataSolid-sate Properties Al Mixed Oxides Sputter-deposited Al Alloys.
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