Search results for " fibre"
showing 10 items of 285 documents
Effect of Fibre-Enriched Orange Juice on Postprandial Glycaemic Response and Satiety in Healthy Individuals: An Acute, Randomised, Placebo-Controlled…
2019
Background: Consumption of fibre-enriched orange juice may be an appropriate way to supplement daily fibre intake and achieve beneficial effects on metabolic health. The present study aimed to assess the short-term effects of fibre-enriched orange juice on postprandial metabolism and satiety in a healthy adult population. Methods: In this double-blind, randomised, placebo-controlled, crossover study 10 healthy subjects underwent two one-day trials in which they consumed an orange juice beverage containing 1.4 g/100 mL of citrus fibre (29.3% soluble and 41.9% insoluble) or a placebo (regular orange juice without added fibre). Postprandial glucose, insulin, gut hormones (GLP1, GIP and ghrelin…
Almond shell reuse: a viable non-conventional aggregate for sustainable building materials
2022
Bio-based or green architecture is a new way of designing and building in line with the European Green Deal and in light of the Circular Economy principles. The main green approach directs the whole construction life cycle to be eco-sustainable and environmentally friendly from the beginning to the end of the building process. Beyond the use of eco sustainable and highly performing structural materials, new technologies able of reduce the environmental impact of buildings must be used. This paper is aimed at reviewing the possible reuse of bio- wastes of agricultural origin whose massive production generates a number of issues for their treatment and disposal. In particular, this study will…
Simplified technique for constitutive analysis of SFRC
2014
Steel fibre reinforced concrete (SFRC) has become widespread material in areas such as underground shotcrete structures and industrial floors. However, due to the absence of material models of SFRC reliable for numerical analysis, application fields of this material are still limited. Due to interaction of concrete with fibres, a cracked section is able to carry a significant portion of tensile stresses, called the residual stresses. In present practices, residual stresses used for strength, deflection and crack width analysis are quantified by means of standard tests. However, interpretation of these test results is based on approximation using empirically deduced relationships, adequacy o…
A CFD MODEL FOR THE PERFORMANCE PREDICTION OF HOLLOW FIBRE HAEMODIALYSIS MODULES
2020
Objectives: The model proposed aims to predict how geometric, transport and operative parameters affect the performances of hollow-fibre membrane modules for haemodialysis, especially solute clearance. Methods: A two-scale approach was used. Preliminarily, dialysate flow and mass transfer around fibre bundles were simulated at Unit Cell level, i.e. in a single periodic unit of the bundle. For a given porosity, both regular lattices (square or hexagonal) and random fibre arrangements were studied. From the predicted friction coefficients and Sherwood numbers, permeability and solute exchange terms were derived to be used in a porous media model of the whole module. Solute concentrations on t…
Stress Transfer within CNT Fibres: A FEA Approach
2015
Abstract Carbon nanotube (CNT) fibres are characterized by extreme anisotropy in their structure and physical properties. These fibres have been shown to have high axial strength, but poor shear strength between carbon nanotubes; for this reason it is difficult to transfer stress uniformly acrossthe fibre cross section. Here, Finite Element Analysis (FEA) is used to predict the stress distribution and the stress-strain curves of CNT fibres. The resultsdemonstrate that, in accordance with St. Venant principle,very considerable length-to-diameter ratios (> 10 3 ) are required to obtain a uniform stress distribution within the fibres even in the presence of low applied strain.
EFFETTO DI TIPOLOGIA E FUNZIONALIZZAZIONE DI NANOTUBI DI CARBONIO SULLE PROPRIETA’ DI FIBRE A MATRICE POLIAMMIDICA
2012
Si riportano i risultati relativi all'utilizzo di due campioni di CNT: uno commerciale (purezza 90%, L/D ≈ 50) ed uno sintetizzato e purificato ad hoc (purezza 99%, L/D ≈ 500) come filler per la realizzazione di fibre a matrice poliammidica. In particolare, si è investigato l’effetto della funzionalizzazione mediante plasma sulle proprietà reologiche, meccaniche ed elettriche delle fibre ottenute. La quantità di carica (2%) e le condizioni operative di trattamento al plasma sono state ricavate da studi precedenti. Le misure di viscosità elongazionale condotte sui campioni a base di CNT tal quali e funzionalizzati hanno messo in luce come l’introduzione della carica comporti un netto increme…
Mineral nutrients in leaves and bast of pedunculate oak (Quercus Robur L.) at different states of defoliation
1998
Abstract Adult oaks (age > 135a) with different grade of defoliation were investigated for their mineral nutrient contents in leaves and bast. In the leaves of the trees with a defoliation of more than 60 % lower concentrations of almost all nutrients were found. No differences were found between defoliation class 1 (defoliation ≤ 25 %) and defoliation class 2 (defoliation ≤ 45 %). In all defoliation classes the mineral nutrient contents are in the normal range except the contents of magnesium, which is in the range of deficiency in all defoliation classes. The mineral contents in bast showed high concentrations of cadmium, manganese zinc, and aluminum in dead trees, and in the case of cadm…
Fibre Bragg gratings tuned and chirped using magnetic fields
1997
The authors report on the use of magnetic fields in conjunction with magnetostrictive materials for tuning and chirping optical fibre Bragg gratings. The Bragg wavelength shifts as a consequence of the strain induced in the fibre by a magnetostrictive rod when a magnetic field is applied. A tuning range of 1.1 nm has been achieved by a magnetic field of 103 mT and the grating has been chirped by applying non-uniform magnetic fields.
TENACITÀ ALLA FRATTURA INTERLAMINARE DI COMPOSITI CFRP SOTTOPOSTI A PROCESSI DI INVECCHIAMENTO IDROTERMICO
2011
In questo lavoro si è condotto uno studio degli effetti dell’invecchiamento idrotermico sulla tenacità alla frattura interlaminare in Modo I di laminati in composito CFRP con lay-up unidirezionale. I pannelli realizzati impiegano una resina epossidica DGEBA. Provini DCB sono stati ricavati in accordo con la norma ASTM D5528. Prove dinamico meccaniche DMTA sono state condotte per analizzare l’influenza dell’invecchiamento sulla temperatura di transizione vetrosa, e quindi sul grado di fragilità della matrice. Il lavoro descrive il set-up sperimentale per la determinazione delle Curve R, evidenziando l’influenza della morfologia del tessuto in carbonio. I valori di GIC di innesco e di propaga…