Search results for "Note"
showing 10 items of 10709 documents
Studio delle proprietà meccaniche di compositi rinforzati con nanotubi in carbonio mediante un nuovo approccio numerico misto
2012
I CNTs primeggiano in rigidezza, resistenza a rottura, resilienza, allungamento a rottura, conducibilità termica e conducibilità elettrica. Un modo di avvantaggiarsi delle loro singolari proprietà consiste nell’incorporarli in una matrice per costruire materiali compositi nanostrutturati. Questo articolo presenta un nuovo modello misto, numerico-analitico, che consente di prevedere le caratteristiche elastiche di nanocompositi con distribuzione random dei CNTs, tenendo conto della curvatura che gli stessi mostrano quando sono immersi nel polimero. L’approccio ibrido rappresenta un’apprezzabile evoluzione della modellazione micromeccanica e può essere applicato a qualsiasi composito nanostru…
Vanadium dioxide and gold nanocomposite films for glazing application
2009
Vanadium dioxide is a material with great potential as an intelligent glazing material. The technology is based on a metal to semiconductor transition (MST) where there is an associated structural change from the higher temperature rutile structure to the lower temperature monoclinic structure. This structural transition results in significant changes in optical properties and electrical conductivity. Hybrid aerosol assisted and atmospheric pressure chemical vapour deposition methodology has been utilised, to produce thin films of gold nano-particle vanadium dioxide nanocomposites. Good surface coverage is observed comparable to that of APCVD processes and a variety of different film thickn…
Electrochemical metallization ReRAMs (ECM) - Experiments and modelling: general discussion
2019
Electrochemical metallization ReRAMs (ECM) - Experiments and modelling: General discussion
Advances in selective conversions by heterogeneous photocatalysis
2010
Selective photocatalytic conversions are offering an alternative green route for replacing environmentally hazardous processes with safe and energy efficient routes. This paper reports the most recent advances in the application of heterogeneous photocatalysis to synthesize valuable compounds by selective oxidation and reduction.
Heterogeneous photocatalysis from fundamentals to possible applications
2017
This special issue of Catalysis Today Journal, is dedicated to the career of Prof. Vincenzo Augugliaro, University of Palermo, Italy, in the occasion of his retirement in 2015. Prof. Vincenzo Augugliaro was Full Professor of Transport Phenomena at the University of Palermo (Italy) since 1994. He contributed to the fol- lowing research fields: chemical absorption kinetics, biochemical reactor modelling, diffusional kinetics in metallizing alloys and heterogeneous photocatalysis; in this last field he investigated on chemical kinetics of heterogeneous photocatalytic systems, modelling of heterogeneous photoreactors, radiation field in absorbing-reacting media and application of heterogeneous …
Nanochemistry Aspects of Titania in Dye Sensitized Solar Cells
2009
We analyze the main nanochemistry factors affecting photovoltaic performance in TiO2 employed as wide bandgap semiconductor in dye-sensitized solar cells (DSCs). What is the best morphology of the oxide? Which processes yield the required structures? Finally, putting the discussion in the context of the rapid evolution of photovoltaic technologies, we argue that new titania nanostructures will form the basic component of second-generation solar modules based on dye solar cells.
Photocatalytic membrane reactors: fundamentals, membrane materials and operational issues
2013
Abstract: This chapter reports the properties of semiconductor materials used in heterogeneous photocatalysis together with a comparison of heterogeneous photocatalytic systems and a brief description of the types of membranes that can be used. Some aspects of membrane operations, such as fouling, separation of a photocatalyst and effectiveness of photodegradation on permeate quality are discussed.
Particle Suspension in Vortexing Unbaffled Stirred Tanks
2016
Three-phase processes in which particle suspension has to be achieved in conjunction with gas dispersion are traditionally carried out in sparged, baffled stirred tanks. The operation of such tanks can suffer, however, from particles tending to block the sparger holes. A viable alternative might be provided by uncovered unbaffled stirred tanks (UUSTs), where gas self-injection can occur when the free-surface vortex reaches the impeller blades and gas bubbles begin to be ingested by the liquid. In this work, the particle suspension and liquid aeration performances in three-phase UUSTs were experimentally investigated and compared with relevant literature correlations concerning baffled syste…
Techno-economic assessment of multi-effect distillation process for the treatment and recycling of ion exchange resin spent brines
2019
Abstract A treatment chain including nanofiltration, crystallization and multi-effect distillation (MED) is for the first time proposed for the treatment of an effluent produced during the regeneration of Ion Exchange resins employed for water softening. The goal is to recover the minerals and to restore the regenerant solution to be reused in the next regeneration cycle. MED is the most crucial unit of the treatment chain from an economic point of view. A techno-economic analysis on the MED unit was performed and a novel performance indicator, named Levelized Brine Cost, was introduced as a measure of the economic feasibility of the process. Different scenarios were analysed, assuming diff…
New considerations for modelling a MED-TVC plant under dynamic conditions
2019
Abstract The multiple-effect distillation (MED) technology is nowadays the most promising desalination process to be coupled with variable heat sources, thus leading to a more sustainable way to produce water. In order to prove the potential of this, it is of major interest to develop powerful modelling tools to predict the performance of this coupling. Only a few models have been presented so far. They show promising results but were based on some simplifying assumptions and non-physical constraints that could limit the analysis of the dynamic behaviour of a MED plant. This paper presents new considerations for the dynamic modelling of a MED plant associated with a thermal vapour compressi…