Search results for "Materials Science | Hot Paper"
showing 10 items of 1457 documents
Asphalt mixtures modified with basalt fibres for surface courses
2018
Abstract This paper shows the results of an experimental study concerning the effect of introduction of basalt fibres in asphalt mixtures for surface course, mainly with regard to those to be used in urban areas, for dedicated bus lanes. Surface layers, where tire-pavement interactions occur, have to provide different properties such as high friction (very important for users’ safety), stability, resistance to meteorological agents, and contribution to the overall pavement performances. Considering that basalt fibres provide considerable physical and mechanical properties and above all high abrasion resistance, scope of the study is to evaluate the effects of these fibres on mixtures proper…
Unraveling materials Berry curvature and Chern numbers from real-time evolution of Bloch states
2019
Materials can be classified by the topological character of their electronic structure and, in this perspective, global attributes immune to local deformations have been discussed in terms of Berry curvature and Chern numbers. Except for instructional simple models, linear response theories have been ubiquitously employed in calculations of topological properties of real materials. Here we propose a completely different and versatile approach to get the topological characteristics of materials by calculating physical observables from the real-time evolving Bloch states: the cell-averaged current density reveals the anomalous velocities whose integration leads to the conductivity quantum. Re…
Effect of Graphene Nanoplatelets on the Physical and Antimicrobial Properties of Biopolymer-Based Nanocomposites
2016
In this work, biopolymer-based nanocomposites with antimicrobial properties were prepared via melt-compounding. In particular, graphene nanoplatelets (GnPs) as fillers and an antibiotic, i.e., ciprofloxacin (CFX), as biocide were incorporated in a commercial biodegradable polymer blend of poly(lactic acid) (PLA) and a copolyester (BioFlex®). The prepared materials were characterized by scanning electron microscopy (SEM), and rheological and mechanical measurements. Moreover, the effect of GnPs on the antimicrobial properties and release kinetics of CFX was evaluated. The results indicated that the incorporation of GnPs increased the stiffness of the biopolymeric matrix and allowed for the t…
Bisphosphonate-polyaspartamide conjugates as bone targeted drug delivery systems.
2015
Poly-hydroxy-aspartamide was used as a backbone to synthesize bisphosphonate derivatives thus achieving macromolecular carriers to be potentially used as targeting agents for bone drug delivery. Molecules bearing bisphosphonate groups, such as aminobisphosphonate (ABP) and neridronate (NRD), have been conjugated to polyaspartamide (α,β-poly(N-2-hydroxyethyl)-dl-aspartamide, PHEA), with or without a spacer (succinic acid or 6-aminocaproic acid) thus obtaining PHEA-succinate-ABP and PHEA-caproylcarbamate-ABP and PHEA-ABP and PHEA-NRD, respectively. Bisphosphonate-polymer conjugates were physico-chemically characterized using size exclusion chromatography and 1H-NMR; and their in vitro and e…
Low-fouling, mixed-charge poly-L-lysine polymers with anionic oligopeptide side-chains
2018
Biosensors and biomedical devices require antifouling surfaces to prevent the non-specific adhesion of proteins or cells, for example, when aiming to detect circulating cancer biomarkers in complex natural media (e.g., in blood plasma or serum). A mixed-charge polymer was prepared by the coupling of a cationic polyelectrolyte and an anionic oligopeptide through a modified "grafting-to" method. The poly-l-lysine (PLL) backbone was modified with different percentages (y%) of maleimide-NHS ester chains (PLL-mal(y%), from 13% to 26%), to produce cationic polymers with specific grafting densities, obtaining a mixed-charge polymer. The anionic oligopeptide structure (CEEEEE) included one cysteine…
Spin qubits with electrically gated polyoxometalate molecules
2007
Spin qubits offer one of the most promising routes to the implementation of quantum computers. Very recent results in semiconductor quantum dots show that electrically-controlled gating schemes are particularly well-suited for the realization of a universal set of quantum logical gates. Scalability to a larger number of qubits, however, remains an issue for such semiconductor quantum dots. In contrast, a chemical bottom-up approach allows one to produce identical units in which localized spins represent the qubits. Molecular magnetism has produced a wide range of systems with tailored properties, but molecules permitting electrical gating have been lacking. Here we propose to use the polyox…
Perfluoroalkyl substances in Breast milk, infant formula and baby food from Valencian Community (Spain)
2016
Environmental and human exposures to perfluoroalkyl substances (PFASs) are of emerging concern since they are persistent and bioaccumulative. The present study reports PFASs levels in human milk, infant formulas and baby food (dry cereals and pots) from the Valencian Community (Spain) in order to evaluate the infant exposure to these substances through the diet. The results show that perfluorobutanoic acid (PFBA) and perfluorooctanoic acid (PFOA) were in all the samples of the four selected matrices (except PFOA in one sample of dry cereal baby food). Perfluoroheptanoic acid (PFHpA) and perfluorodecanoic acid (PFDA) were also detected in 70% of the breast milk samples. In infant formulas, P…
Recent progress in developing a feasible and integrated conceptual design of the WCLL BB in EUROfusion project
2019
The water-cooled lithium-lead breeding blanket is in the pre-conceptual design phase. It is a candidate option for European DEMO nuclear fusion reactor. This breeding blanket concept relies on the liquid lithium-lead as breeder-multiplier, pressurized water as coolant and EUROFER as structural material. Current design is based on DEMO 2017 specifications. Two separate water systems are in charge of cooling the first wall and the breeding zone: thermo-dynamic cycle is 295–328 °C at 15.5 MPa. The breeder enters and exits from the breeding zone at 330 °C. Cornerstones of the design are the single module segment approach and the water manifold between the breeding blanket box and the back suppo…
Recognition of polychromatic three-dimensional objects
2004
We propose to use optical multichannel correlation in various chromatic systems to obtain a setup for recognition of polychromatic three-dimensional (3-D) objects based on Fourier-transform profilometry. Because red-green-blue color components are not able to split the luminance information of objects in a defined component, when the 3-D objects are brighter than the reference objects the correlation result gives false alarms. We demonstrate that it is possible to use different color spaces that can split luminance from chromatic information to yield adequate recognition of polychromatic 3-D objects. We show experimental results that prove the utility of the proposed method.
On site consolidation of burnt and partially charred wood in dry conditions
2011
Abstract Forty years ago in a xx th-century church in Torino, a small fire partially burned some of the decorative external boards of the sound-box of the organ. The focus of this present work was to find a treatment able to consolidate partially burnt wood in dry conditions, in which the external charred layer would be lost if not well preserved because of its incoherence. The product had to be applied onsite on an architectural structure intended to be reused again (and not simply exhibited). This circumstance is rarely encountered in the conservation of wooden Cultural Heritage. The efficacy of treatments was evaluated on the basis of a suitable and original experimental methodology, whi…