Search results for "Materiali"
showing 10 items of 876 documents
Using Taguchi method for the optimization of processing variables to prepare porous scaffolds by combined melt mixing/particulate leaching
2017
Synthetic biopolymers have made significant inroads into the development of devices for tissue regeneration. In this context, a challenge is the achievement of appropriate properties mimicking the natural extracellular matrix by fabricating scaffolds presenting mechanical properties, specific surface, porosity and pore interconnection adequate for the final application. This study involved a systematic procedure based on Taguchi method for parameters optimization of melt mixing/particulate leaching combined processes aiming to enhance the performance of the scaffolds. In particular, it was evaluated the effect of time and temperature of melt mixing of the poly(lactic acid) matrix with two w…
Microwave response properties of epoxy resin composites filled with graphitic fillers
2014
Composite materials based on epoxy resin filled with various kinds of graphite particles: exfoliated graphite (EG), natural graphite, and coarse, medium and fine artificial graphites have been prepared. The dielectric permittivity strongly increases with graphite particle size. This effect is related to the distance of the investigated filler concentrations to the composites' percolation threshold. Microwave experiments show that exfoliated graphite is, out of investigated graphite particles, the only one being a really effective additive for producing electromagnetic (EM) interference (EMI) shielding: 2 wt.% epoxy/EG is absolutely opaque to electromagnetic radiation at 30 GHz.
Una mañana en Oporto : apuntes de un viaje en la arquitectura de Álvaro Siza
2023
Per un architetto il viaggio è una impareggiabile occasione di studio, poiché permette di compiere una reale esperienza dello spazio, consente di valutare con i propri sensi ciò che altrimenti sarebbe sempre mediato dal disegno, dalla fotografia, dai testi o da altre rappresentazioni. La visita ad alcune architetture di Álvaro Siza, diviene occasione per una analisi critica e consente di estrarre alcune lezioni sul rapporto con i luoghi, sui caratteri dello spazio, sulla materialità, sull’impiego della luce, sul valore del dettaglio.
The effect of through-thickness compressive stress on mode II interlaminar fracture toughness
2017
Abstract The effect of through-thickness compressive stress on mode II interlaminar fracture toughness is investigated experimentally and replicated numerically. The modified Transverse Crack Tensile specimen recently proposed by the authors is used, together with an experimental device designed to apply a constant transverse compressive stress on the surface of the specimen. Experiments are conducted using IM7/8552 specimens for different compressive stresses, ranging from 0 to 100 MPa, covering all the practical applications commonly encountered in the aeronautical industry (e.g., tightened filled holes or bolted joints). It is shown that mode II interlaminar fracture toughness increases …
Structural performances of pultruded GFRP emergency structures – Part 2: Full-scale experimental testing
2019
Abstract This paper presents an experimental testing of a pultruded glass fiber reinforced polymer (FRP) structure used for emergency applications continuing the discussion presented in a previous paper (part 1) where the study of the characteristics of material and elements are presented. First, the design of the composite structure and components and the evaluation of the structural behavior by means of numerical and analytical approach according to current regulatory codes are described. In this frame, the global and local response was observed according to load paths deriving from the design loads at limit states. Then, the experimental test on a full-scale 2D model is presented at diff…
Do Videogames Simulate? Virtuality and Imitation in the Philosophy of Simulation
2015
Simulation. The concept of simulation has been contested in academia since its proliferation in the 1960s. This is hardly the case in videogame research, the subject of which is commonly discussed as a simulation or something that simulates with little analytical consideration of the term’s other scientific roles. Comparison. The article compares the simulation of videogame research to the ways in which other scientific sectors utilize the term. Problematic science communication. It turns out that videogame research has found an eccentric use for simulation with none or little relation to the term’s scientific (knowledge-driven) and etymological (imitational) predecessors. This becomes a p…
The reception of Marx's thought in the young Habermas
2018
RESUMEN Se analiza la influencia del pensamiento de Marx en la formulación temprana de la teoría habermasiana. Para ello, se parte de las críticas de Albrecht Wellmer y Jürgen Habermas a la autocomprensión marxiana del materialismo histórico. Luego se estudia la reconstrucción de algunos postulados del marxismo llevada a cabo por Habermas en términos de una renovada teoría de la evolución social. Con ello salen a la luz algunos supuestos básicos de la teoría de Marx que aparecen trasformados en la conceptualización de Habermas y que constituyen una base ineludible para comprender el posterior pensamiento de este autor. ABSTRACT The article analyzes the influence of Marx's thought on the for…
Behavior in compression of concrete cylinders externally wrapped with basalt fibers
2015
Abstract This paper gives additional information on the use of new class of composites constituted by Basalt Fiber Reinforced Polymer (BFRP) bonded with epoxy resin to concrete specimens as an alternative confinement material for compressed concrete members with respect to carbon or glass fibers. From the experimental point of view, concrete cylinders are wrapped with continuous fibers, in the form of sheets, applying both full and partial discrete wrapping with BFRP straps, and then tested in compression. For comparison, few other concrete cylinders are wrapped with Carbon Fiber Reinforced Polymer (CFRP) sheets and tested in compression. The number and type of plies (full or partial wrappi…
On the use of PET-LCP copolymers as compatibilizers for PET/LCP blends
1996
Copolyesters of poly[ethylene terephthalate) (PET) with a liquid crystalline polymer (LCP), SBH 1:1:2, have been synthesized by the polycondensation, carried out in the melt at temperatures up to 300 degrees C of sebacic acid (S), 4,4'-dihydroxybiphenyl (B), and 4-hydroxybenzoic acid (H) in the presence of PET. The PET-SBH copolyesters have been characterized by differential scanning calorimetry, scanning electron microscopy, X-ray diffraction, etc., and the relationships between properties and preparation conditions are discussed. The copolyesters show a biphasic nature, which is more evident for the products synthesized with a thermal profile comprising relatively lower temperatures (220-…
Anxious and status signaling: Examining the link between attachment style and status consumption and the mediating role of materialistic values
2021
Attachment theory has recently been recognized as a potentially fruitful avenue for studying consumer behavior. However, few studies have examined the relationship between attachment styles and consumer preferences. Based on literature suggesting that individuals with an anxious attachment style have a particularly strong need for attention, we conducted two studies with a total sample of over 2,000 participants, which tested and found that anxiously attached consumers displayed a higher propensity to purchase status-signaling goods than their counterparts with secure attachment styles. This effect was mediated by materialistic values, such that participants with an anxious attachment style…