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71.
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The processing of peaches to produce fruit pulp generates solid and liquid wastes rich in phytochemicals, such as carotenoids; thus, the objective of this work was to study the use of this waste for carotenoid extraction based on a complete experimental design and using response surface methodology. The parameters studied were the amount of solvent (20–50 mL), the number of extractions (1–5) and the extraction time (10–30 min). The extracts were analysed by spectrophotometry and the optimised conditions by HPLC. The optimised results were four extractions of 10 min using 38.5 mL of ethanol, which presented a yield of 168.59 μg g?1 DW of total carotenoids of which 67.55 μg g?1 corresponds to β‐carotene, 86.75 μg g?1 to cryptoxanthin, 12.08 μg g?1 to zeaxanthin and 2.2 μg g?1 to lutein, which representing 66% of extraction pigments relative to the total content of carotenoids present in the peach waste.  相似文献   
73.
In this article, an alternative mechanical recycling of multilayer carton scraps (MC), consisting in the use of MC without the physical separation of its different fractions (cellulose fibers and low‐density polyethylene, 80/20 wt/wt), is proposed. In particular, MC was considered as a source of cellulose fibers in the obtainment of high‐density polyethylene (HDPE)‐based composites. Composites containing up to 60 wt % of milled MC were prepared by reactive processing, i.e., by adding different amount (5 and 10 wt %) of a linear low‐density polyethylene grafted with maleic anhydride (coupling agent, maleated linear low‐density polyethylene) during HDPE/MC mixing. Then, structure/properties relationships were deeply investigated as a function of MC and coupling agent content. The coupling agent was able to induce a complete polymeric covering of cellulose fraction as well as a strong HDPE/cellulose interfacial adhesion. As a consequence, a significant improvement of mechanical properties at low and high deformation rates as well as a very interesting response of composites to water vapor permeability was obtained. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
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Sulforaphane (SFN) is a phytocompound belonging to the isothiocyanate family. Although it was also found in seeds and mature plants, SFN is mainly present in sprouts of many cruciferous vegetables, including cabbage, broccoli, cauliflower, and Brussels sprouts. SFN is produced by the conversion of glucoraphanin through the enzyme myrosinase, which leads to the formation of this isothiocyanate. SFN is especially characterized by antioxidant, anti-inflammatory, and anti-apoptotic properties, and for this reason, it aroused the interest of researchers. The aim of this review is to summarize the experimental studies present on Pubmed that report the efficacy of SFN in the treatment of neurodegenerative disease, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and multiple sclerosis (MS). Therefore, thanks to its beneficial effects, SFN could be useful as a supplement to counteracting neurodegenerative diseases.  相似文献   
76.
Non-spherical colloids provided with well-defined bonding sites—often referred to as patches—are increasingly attracting the attention of materials scientists due to their ability to spontaneously assemble into tunable surface structures. The emergence of two-dimensional patterns with well-defined architectures is often controlled by the properties of the self-assembling building blocks, which can be either colloidal particles at the nano- and micro-scale or even molecules and macromolecules. In particular, the interplay between the particle shape and the patch topology gives rise to a plethora of tilings, from close-packed to porous monolayers with pores of tunable shapes and sizes. The control over the resulting surface structures is provided by the directionality of the bonding mechanism, which mostly relies on the selective nature of the patches. In the present contribution, we investigate the effect of the patch size on the assembly of a class of anisotropic patchy colloids—namely, rhombic platelets with four identical patches placed in different arrangements along the particle edges. Larger patches are expected to enhance the bond flexibility, while simultaneously reducing the bond selectivity as the single bond per patch condition—which would guarantee a straightforward mapping between local bonding arrangements and long-range pattern formation—is not always enforced. We find that the non-trivial interplay between the patch size and the patch position can either promote a parallel particle arrangement with respect to a non-parallel bonding scenario or give rise to a variety a bonded patterns, which destroy the order of the tilings. We rationalize the occurrence of these two different regimes in terms of single versus multiple bonds between pairs of particles and/or patches.  相似文献   
77.
A hybrid material composed by a thermotropic liquid crystal (LCP) polymer (HBA–PET) and single wall carbon nanotubes has been produced in order to study the interaction at the interface matrix/filler for possible applications in electronics and optics. The nanocomposites are characterized by a mosaic-like morphology, with regions of randomly placed LC fibers intercalated with regions formed by aligned polymer fibers, that trigger in turn the alignment of carbon nanotube bundles by means of P stacking interaction. Moreover an effective electronic interaction between the nanocomposite components is demonstrated by combining use of photoluminescence and Raman spectroscopy. The photoinduced charge transfer between SWCNT and polymer could be explain on the basis of the injection of holes (generated in the polymer by light absorption), into the SWCNT valence band and followed by a radiationless decay of the excited polymer’s electron.  相似文献   
78.
Electron transfer through peptide scaffolds has been studied for a long time as a useful and simple approach to investigate the mechanisms of the ubiquitous electron-transfer processes in biology. Here, we review our long-standing work in the field, focused on the study of the electronic conduction properties of hybrid devices based on peptide films immobilized on metal surfaces. In particular, we describe the electrochemical and photoelectrochemical properties of peptide-based self-assembled monolayers chemically linked to gold substrates through a disulfide group. Very recently, this work culminated in the construction of a prototype dye-sensitized solar cell, the photoactive element of which was constituted by a helical oligopeptide functionalized with a near-UV-absorbing chromophore. We also take advantage of the occasion to critically review the state of the art of the field, with suggestions for the issues needing further investigation.  相似文献   
79.
Antioxidant capacity of a number of balsamic vinegar (BV) and traditional balsamic (TBV) vinegars from the districts of Modena and Reggio Emilia (Italy) have been assessed using two chemical assays, the Briggs–Rauscher oscillating reaction method and the Trolox equivalent antioxidant capacity (TEAC) method. The total reducing power was also evaluated using the Folin–Ciocalteu reagent. The results show that the antioxidant parameters of TBV are significantly better than those of the BV, in agreement with the different manufacturing procedures and product ageing. A good correlation was found between the methods used. Suggestion for an approximate evaluation of ageing based on antioxidant parameters values is also given.  相似文献   
80.
This paper deals with the cooperative strategies, which can be adopted in emergency scenarios by integrating space and terrestrial segments, and communication and localization services. First, the cooperative solutions for integrated Navigation and Communication systems are reviewed and an effective software‐defined radio implementation is described. Then, cooperative systems for broadcast and multicast communications in Incident Area Network are proposed and evaluated: in the broadcast scenario, low‐complexity relaying techniques are adopted to overcome the propagation impairments and the performance degradation; in the multicast system, radio resources management techniques for group communications are designed to allow the efficient use of scarce resources and improve connectivity and reliability of the overall system. The technical solutions have been studied and tested in the framework of the Italian National Research Project SAtellite‐assisted LocalIzation and Communication system for Emergency services [1]. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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