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991.
Valentina Sovrani Massimo Blandino Valentina Scarpino Amedeo Reyneri Jean Daniel Coïsson Fabiano Travaglia Monica Locatelli Matteo Bordiga Rosa Montella Marco Arlorio 《Food chemistry》2012
Wheat kernels are rich in antioxidant compounds, that are mainly present in the outer bran layers and which are removed during milling. Unfortunately, several contaminants, e.g., mycotoxins and heavy metals, are also concentrated in the external layers. Pearling of 3 wheat varieties gave five fractions (each 5% of the original grain weight), starting from the outer layer until the inner kernel, designated as 0–5%, 5–10%, 10–15%, 15–20%, 20–25%, respectively. The remaining 75% of the inner kernel was also collected. Dietary fibre, free phenolic acids and total antioxidant activity decreased progressively from the external to the internal layers. However, the 5–10% fraction was richer in β-glucan content than the external one (0–5%). Heavy metals were only found in the most external fraction. Deoxynivalenol contamination decreased from the external to the internal layers: 64% of total contamination of kernel was found in the 0–5% and 5–10% fractions. The 10–15% kernel fraction offered the best compromise between high nutritional value and low contamination risk. 相似文献
992.
Giulia Giuntoli Luca Rosi Marco Frediani Barbara Sacchi Piero Frediani 《应用聚合物科学杂志》2012,125(4):3125-3133
A series of sixteen fluoro-functionalized poly(lactic acid)s were synthesised using two commercial fluorinated alcohols [3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluoro-1-octanol and 4-(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)benzyl alcohol] as co-initiators in the ring-opening polymerization of L-lactide and rac-lactide (the racemic mixture of L- and D-lactide) catalyzed by Tin(II) 2-ethylhexanoate. The polymers were characterized by NMR, IR, GPC, DSC and tested as potential protective coating for stone. The performances were comparatively evaluated in terms of water protection efficacy and colour changes of the treated stone. Furthermore, the photo-stability of nine selected polymers under Solar Box condition was also investigated. It has been shown that the presence of fluorine makes the stone more water-repellent. The polymers showed also interesting photo-stability and some of them provided a behavior close to PLA-FLK-PLA block copolymers recently reported in the literature, in spite of their lower fluorine content © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
993.
Emanuela Tamburri Valeria Guglielmotti Silvia Orlanducci Maria Letizia Terranova Daniela Sordi Daniele Passeri Roberto Matassa Marco Rossi 《Polymer》2012,53(19):4045-4053
The detonation nanodiamond is a novel versatile nanomaterial with tunable properties and surface chemistry. In this work, we report on a template-free method to synthesize polyaniline based nanocomposite fibers during a chemical oxidative precipitation polymerization where the cooperative interactions between nanodiamond and polyaniline nucleates trigger the final morphology of the nanocomposite. FE–SEM and TEM observations evidence the prominent growth of fibril-like structures assembled in 2-D networks of tightly woven, partially oriented fibers. Optical and Raman spectroscopy and X-ray diffraction analyses reveal that the polymer chains are in a protonated emeraldine form and organize themselves in a highly ordered 3-D spatial arrangement. Conductivity measurements performed on isolated fibers by a conductive tip of an AFM apparatus highlight that the diamond filler does not affect the conductive properties of the polyaniline matrix while increases the thermal stability of the polymer as confirmed by TGA studies. 相似文献
994.
In the present work we demonstrate that functional polymer microgels may act as smart self-catalyzing system inducing controlled formation of silica nanoparticles inside the polymer network and formation of hybrid colloids. We synthesized a water soluble silica precursor PEG-PEOS via post-modification of hyperbranched poly(ethoxysiloxane) (PEOS) with poly(ethylene glycol) monomethyl ether. We used poly(N-vinylcaprolactam)-based microgel functionalized with imidazole and β-diketone groups as a matrix for biomimetic deposition of silica. Composite microgel particles containing silica nanoparticles (up to 20 wt.-%) have been prepared by simultaneous PEG-PEOS conversion and silica deposition in the microgels. TEM studies indicate the infiltration of silica nanoparticles (~10 nm) inside the corona region of the microgels due to the strong acid–base interaction between the acidic silica and basic imidazole groups. The resulting composite particles were found to be colloidally stable and no aggregation was observed even after months of storage. The incorporation of silica nanoparticles increased the rigidity of the microgel particles and reduced their thermal sensitivity. 相似文献
995.
Marica Consolini Michela Sega Chiara Zanetti Marina Fusi Roberto Chignola Marco De Carli Corrado Rizzi Gianni Zoccatelli 《Food Analytical Methods》2012,5(2):234-243
Wheat α-amylase inhibitors (α-AIs) are known anti-nutritional factors, respiratory allergens, and they can sporadically cause
food allergy. α-AIs are therefore expected to reach the enteric mucosae in an immunologically active form, but information
on their stability to gastric digestion is not available. Resistance to pepsinolysis is nonetheless a key factor for any food
allergen. We therefore investigated whether α-AIs could resist pepsin digestion in simulated gastric fluids (SGF) and in emulsified
SGF, the latter simulating more realistically the multi-phase nature of stomach bolus. Since α-AIs comprise a huge family
of proteins, we investigated 0.19 α-AI as a prominent member. The digestion patterns were analyzed by immunoblotting using
anti-0.19 polyclonal antibodies and sera from wheat allergic patients sensitized to 0.19 α-AI. The results show that the immune
epitopes of α-AI are detectable up to 120 min of digestion in emulsifying conditions. Intra-molecular disulfide bonds and,
in particular, emulsification were found to be crucial factors for protein stability. The results show that 0.19 α-AI must
be considered a potential food allergen. 相似文献
996.
A multisite, vibrotactile sensory substitution system, that could be used in conjunction with artificial touch sensors in multifingered prostheses, to deliver sensory feedback to upper limb amputees is presented. The system is based on a low cost/power/size smart architecture of off-the-shelf miniaturized vibration motors; the main novelty is that it is able to generate stimuli where both vibration amplitude and frequency as well as beat interference can be modulated. This paper is aimed at evaluating this system by investigating the capability of healthy volunteers to perceive-on their forearms-vibrations with different amplitudes and/or frequencies. In addition, the ability of subjects in spatially discriminating stimulations on three forearm sites and recognizing six different combinations of stimulations was also addressed. Results demonstrate that subjects were able to discriminate different force amplitudes exerted by the device (accuracies greater than 75%); when both amplitude and frequency were simultaneously varied, the pure discrimination of amplitude/frequency variation was affected by the variation of the other. Subjects were also able to discriminate with an accuracy of 93% three different sites and with an accuracy of 78% six different stimulation patterns. 相似文献
997.
Sperandio M Guermandi M Guerrieri R 《IEEE transactions on bio-medical engineering》2012,59(2):383-389
A four-shell head phantom has been built and characterized. Its structure is similar to that of nonhomogeneous concentric shell domains used by numerical solvers that better approximate current distribution than phantoms currently used to validate electrical impedance tomography systems. Each shell represents a head tissue, namely, skin, skull, cerebrospinal fluid, and brain. A novel technique, which employs a volume conductive impermeable film, has been implemented to prevent ion diffusion between different agar regions without affecting current distribution inside the phantom. Comparisons between simulations and phantom measurements performed over four days are given to prove both the adherence to the model in the frequency range between 10 kHz and 1 MHz and its long-term stability. 相似文献
998.
999.
Daehyun Wee Boris Kozinsky Barbara Pavan Marco Fornari 《Journal of Electronic Materials》2012,41(6):977-983
We report an ab?initio study of vibrational and thermodynamic properties of TiNiSn, a half-Heusler alloy that has been investigated in the context of thermoelectrics, based on density functional theory and density functional perturbation theory. The quasiharmonic approximation, where the Helmholtz free energy obtained from phonons of multiple strained structures is fitted to a model equation of state, is employed to estimate thermodynamic properties. Good quantitative correspondence is achieved between experimental observations and our theoretical calculation for various thermodynamic quantities: lattice parameter, thermal expansion coefficient, and heat capacity. Estimates of lattice thermal conductivity are also provided by using a semianalytic model previously proposed in the literature. Though this yields good qualitative agreement, a more accurate ab?initio approach that explicitly includes anharmonic interactions between atoms should be employed for quantitative predictions of thermal conductivity. 相似文献
1000.
Enrico Baccaglini Marco Grangetto Emanuele Quacchio Simone Zezza 《Signal Processing: Image Communication》2012,27(5):430-437
In this work we propose an hybrid CDN–P2P architecture for video contents delivery based on the NextShare platform. Experiments were conducted over the PlanetLab network using a number of peers which encompass real network behaviors. Results show that although the NextShare is based on the original BitTorrent file sharing mechanism, the implemented tools can efficiently deliver video over a heterogeneous and time varying network if peers can rely on an intermediate distribution layer between the CDN and the final users. Among the other benefits, CDN edge servers are significantly offloaded and peers can experience low start-up delays. Architecture design and simulation results are taking place in the context of the European FP7 project COAST. 相似文献