Search results for "scienza"

Introduzione. La spola e la synkrisis

2010

Prometeo genetista. Profitti delle tecniche e metafore della scienza

2016

Il saggio di Claude Calame affronta una tematica di grande rilievo scientifico, ossia il confronto tra il valore epistemologico e sociale dell'uso delle arti tecniche nell'antica Grecia e il valore epistemologico del linguaggio della scienza moderna in particolare applicato all'ambito della genetica e delle moderne biotecnologie e scienze di laboratorio. Lo spunto del confronto è offerto dall'analisi storico-culturale e antropologica del mito di Prometeo, come è stato diversamente declinato dai vari autori dell'antichità classica, a partire da Esiodo sino a Platone, passando per l'autore del dramma "Prometeo incatenato". In una prospettiva di indagine antropopoietica, le arti tecniche perme…

Effect of NaOH Treatment on Properties of Phoenix Sp. Fiber

2016

The aim of this paper is to investigate the effect of an alkali treatment on physical, chemical, mechanical, and morphological properties of Phoenix Sp. fibers. The use of natural fibers as reinforcement in polymer composites requires a deep investigation to understand their behavior and which treatment is more appropriate to improve the quality of the untreated material. For this reason, fibers were extracted from the petioles of the Phoenix Sp. plant and they were treated with NaOH solution in different weight concentrations (5%, 10%, and 15%). The mechanical behavior was investigated through tensile test on single fiber at different gauge length (20 mm, 30 mm, 40 mm, 50 mm, and 60 mm). C…

Novel green bio-composite geopolymeric thermo-plasters for innovative building applications: upcycling spent coffee ground

2022

This study proposes the reuse of spent coffee ground and biomass fly ash in the development of green geopolymeric thermo-plastering for innovative building applications. The former waste is the major residue of the brewing process, that is usually used as fertilisers or disposed of in landfill with extreme harmfulness for the natural environment. The latter is an industrial waste generated during the Kraft paper-pulp process, that is usually landfilled. The mortar is produced with a combination of metakaolin (30 wt.%) and biomass fly ash (70 wt.%), and natural siliceous sand filled with spent coffee ground (up to 17.5 wt.%). The high amount of reused waste makes the material an optimum cand…

Computational aspects in thermoelasticity by the symmetric boundary element method

2008

Artichoke fibres as potential reinforcement of composite materials: mechanical and thermal characterization

2011

Effect of water absorption on thermal and mechanical properties of thermosetting resins for marine applications

2009

ULTRASONIC WAVES IN HETEROGENEOUS MATERIALS - MECHANICAL CHARACTERIZATION OF HETEROGENEOUS MATERIALS BY MEANS OF ULTRASONIC TESTS AND NUMERICAL MODEL…

2014

This Ph.D thesis treats the propagation of ultrasonic waves in heterogeneous materials. It is widely known how waves propagate in homogeneous materials like metallic ones. But very few aspects are known about the propagation in the heterogeneous materials because of the complex behavior regarding these materials. The heterogeneity can be related with the intrinsic properties, elastic and chemical, of each phase of the material, or with the periodic or random arrangement of inclusions of constant or different shapes. Concrete is a common case. In this work the first chapter gives a description of the main characteristics of heterogeneous materials.. In the second one, the methods of inspecti…

Passive Control of Linear Structures Equipped with non-Linear Viscous Dampers and Amplification Mechanism

2008

Fluid damper devices in civil structures such as buildings or bridges are commonly used as energy absorbers for seismic protection. The problem in the response analysis of structures with filled dampers mainly consists in the fact that, due to the strongly nonlinear behavior of such equipments, the response spectrum technique fails. Moreover, in order to enhance the damping effect various toggle brace configurations have been recently proposed. In this paper by using the concept of power spectral density function compatible with the elastic response spectrum and the stochastic linearization technique, the equivalent damping ratio is obtained. It is shown that once the system is linearized r…

Stochastic seismic analysis of MDOF structures with viscous damper devices

2009

Fluid damper devices in civil structures such as buildings or bridges are commonly used as energy absorbers for seismic protection. The problem in the response analysis of structures with filled dampers mainly consists in the fact that, due to the strongly nonlinear behavior of such equipments, the response spectrum technique fails. In this paper by using the concept of power spectral density function compatible with the elastic response spectrum and the stochastic linearization technique, the equivalent damping ratio is obtained. It is shown that once the system is linearized results obtained by Monte Carlo simulation and those obtained by stochastic analysis are in good agreement. Respons…