1,720,997 research outputs found
Esposizione internazionale interattiva "Nuovi Materiali - 5 components from Marine organisms / new materials / products"
No full textEsposizione internazionale interattiva “Nuovi Materiali - 5 components from Marine organisms / new materials / products”, nell’ambito dell'iniziativa SEA HORIZON / THE EXHIBITION, risultato del progetto Europeo PIER in mostra a Città della Scienza dal 30 ottobre 2014
La manipolazione della risorsa mare e i nuovi materiali
No full textMostra “La manipolazione della risorsa mare e i nuovi materiali” proposta nell’ambito dell'esposizione realizzata da Città della Scienza di Napoli per la dodicesima edizione del Festival BergamoScienza, tenutasi dal 3 al 19 ottobre 2014, dal titolo “La trasformazione della materia di origine marina-cibo e materiali”. La mostra indagava il rapporto tra natura e artificio attraverso materiali innovativi provenienti da componenti di origine marina come alghe, diatomee e crostacei, e l'utilizzo di microrganismi marini come nuova risorsa energetica
I nuovi materiali dal mare
No full textInstallazione “I nuovi materiali dal mare”, nell’ambito della Mostra realizzata da Città della Scienza di Napoli all’interno dell’iniziativa Oltremare tenutasi alla Mostra d’Oltremare a Napoli dal 25 ottobre al 2 novembre 2014
Sprayable polysaccharide-based fiber reinforced emulsions for environmentally sound plasticulture
No full textThe increasing demand for mulching and solarization in agriculture is posing serious problems of environmental concerns. Practically all these films are collected by the farmers and left on the ground borders to be incinerated. The same collection by the farmer is difficult; these films being thinner and damaged, their removal through automatic means is almost impossible. The research has focused on an innovative approach where a sort of sprayable water-based varnish is applied on soil. Such varnish, made of biodegradable polysaccharides mixture, contains biodegradable plasticizers to allow the film to remain elastic for the time needed. Moreover, a set of fibrous natural fillers have been tested, which can be mixed in the varnish or can be preventively applied on soil. The agronomic performances have been measured, together with mechanical properties and degradation behavior. The results seem to confirm the technical feasibility of such approach in developing a sustainable plasticulture. Copyright © 2006 WILEY-VCH Verlag GmbH & Co. KGaA
Renewable polymers and plastics: performance beyond the green
Full text linkRenewable bio-based polymers are one of the effective answers that the bioeconomy offers
to solve the environmental emergency connected to plastics and more specifically fossilbased
plastics. Previous studies have shown that more than 70% of the natural capital cost
associated with plastic derives from the extraction and processing of fossil raw materials
and that the price of fossil plastic would be on average 44% higher if such impact was fully
paid by businesses. The disclosure of the hidden costs of plastics will contribute to dispelling
the myth of the expensiveness of renewable polymers. Nevertheless, the adoption of biobased
plastics in the market must be motivated by their functional properties and not merely
by their green credentials. This article highlights some successful examples of synergies
between chemistry and biotechnology in achieving a new generation of bio-based
monomers and polymers. Their success is justified by the combination of scientific advances
with positive environmental and social fallout
UNSATURATED ALKOXY-SUBSTITUTED POLY(P-PHENYLENE 1,3,4-OXADIAZOLE)S: SYNTHESIS AND CHEMICAL-PHYSICAL CHARACTERIZATION.
No full textImproving the Process Ability of Poly(3-Hydroxybutyrate) By A Polyphenolic Natural Additive
Full text linkThe severe environmental issues generated by the non-biodegradability of most polymeric materials has
fostered the search for more eco-friendly solutions. Polyhydroxybutyrate (PHB), produced by bacterial
cells and easily hydrolyzed is one of appealing choice but its properties are still not competitive with
those of standard polymers. Among others, one reason is related to the fact that the high processing
temperature (due to the high crystallization point) is responsible for severe thermal degradation. In this
paper, the effect of Tannic Acid (TA) as a thermal stabilizing processing agent for HPB is investigated by
rheological as well as calorimetric techniques under conditions similar to those used in real processing
applications. The results show that TA is effective in improving the thermal stability and processability of
PHB, while keeping its biodegradable attitude. Compared to neat PHB, TA containing samples show a
lower and delayed thermal degradation. FTIR measurements support the hypothesis that stabilization is
determined by TA/PHB crosslinkin
A digital twin for (64)Cu production with cyclotron and solid target system
Full text linkOne method for finding reliable and cost-effective solutions for designing radioisotope production systems is represented by the “digital twin” philosophy of design. Looking at cyclotron solid targets, uncertainties of the particle beam, material composition and geometry play a crucial role in determining the results. The difference between what has been designed and what can be effectively manufactured, where processes such as electroplating are poorly controllable and generate large non-uniformities in deposition, must also be considered. A digital twin, where the target geometry is 3D scanned from real models, can represent a good compromise for connecting “ideal” and “real” worlds. Looking at the (64)Ni(p,n)(64)Cu reaction, different Unstructured-Mesh MCNP6 models have been built starting from the 3D solid target system designed and put into operation by COMECER. A characterization has been performed considering the designed ideal target and a 3D scan of a real manufactured target measured with a ZEISS contact probe. Libraries and physics models have been also tested due to limited cross-section data. Proton spectra in the target volume, 3D proton-neutron-photon flux maps, average energies, power to be dissipated, shut-down dose-rate, (64)Cu yield compared with various sources of experimental data and beam axial shifting impact, have been estimated. A digital twin of the (64)Ni(p,n)(64)Cu production device has been characterized, considering the real measured target geometry, paving the way for a fully integrated model suitable also for thermal, structural or fluid-dynamic analyses
Shape Memory behavior of Functionalised Poly(e-caprolactone) Crosslinked by Hexamethylene-Diisocyanate
No full textIn this study, the shape memory behaviour of poly(ε-caprolactone) (PCL) with different crosslinking degrees was investigated. PCL was first functionalised with maleic anhydride (MA) and glycidyl methacrylate (GMA), and successively chemically crosslinked by hexamethylene diisocianate (HMDI). The crosslinking reaction was studied through with a rotational stress rheometer, while the shape memory behaviour was analyzed with cyclic thermomechanical experiments and optical microscopy. The results show that the new materials exhibit good shape memory behaviour and good stability of the shape recovery under consecutive cycles in the range 55 - 70°C, can reach high level of stretching, and are furthermore characterised by high recovery speed. These results are promising for potential practical applications, as biomaterials for embolic devices in minimally invasive surgery
Wound healing and antimicrobial effect of active secondary metabolites in chitosan-based wound dressings: A review
No full textWound healing can lead to complex clinical problems, hence finding an efficient approach to enhance the healing process is necessary. An ideal wound dressing should treat wounds at reasonable costs, with minimal inconveniences for the patient. Chitosan is one of the most investigated biopolymers for wound healing applications due to its biocompatibility, biodegradability, non-toxicity, and antimicrobial activity. Moreover, chitosan and its derivative have attracted numerous attentions because of the accelerating wound healing, and easy processability into different forms (gels, foams, membranes, and beads). All these properties make chitosan-based materials particularly versatile and promising for wound dressings. Besides, secondary natural metabolites could potentially act like the antimicrobial and anti-inflammatory agents and accelerate the healing process. This review collected almost all studies regarding natural compounds applications in wound healing by focusing on the chitosan-based bioactive wound dressing systems. An accurate analysis of different chitosan formulations and the influence of bioactive compounds on their wound healing properties are reported
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