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41.
A fast and reliable method for anthocyanin extraction and identification by HPLC‐DAD‐ESI/MS‐QTOF was used to analyse the anthocyanin composition of commercial red fruit juices (blackberry, redcurrant and pomegranate), purees (strawberry, cherry and raspberry) and concentrates (elderberry, blueberry and red grape). The anthocyanin profile of black carrot juice is also reported. The extraction and analysis method allowed us to detect and quantify a wide range of individual anthocyanins in a simple and rapid way. Pelargonidin‐3‐glucoside was detected in redcurrant for the first time and petunidin‐3‐galactoside quantified for the first time in blueberries. Considering the health benefits that have been associated with anthocyanin consumption, all these fruit and vegetables processed products could appear as a good source of this group of phytochemical compounds for their direct consumption or their use as ingredients for the design of new food product or food supplements.  相似文献   
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The main objective of this study was to configure the acquisition and analysis of low-field magnetic resonance imaging (MRI) to predict physico-chemical characteristics of Iberian loin, evaluating the use of different MRI sequences (spin echo, SE; gradient echo, GE; turbo 3D, T3D), computational texture feature methods (GLCM, NGLDM, GLRLM, GLCM + NGLDM + GLRLM), and data mining techniques (multiple linear regression, MLR; isotonic regression, IR). Moderate to very good correlation coefficients and low mean absolute error were found when applying MLR or IR on any method of computational texture features from MRI acquired with SE or GE. For T3D sequence, accurate results are only obtained by applying IR on GLCM or GLCM + NGLDM + GLRLM methods. Considering not only the accuracy of the methodology but also consumed time and required resources, the use of SE sequences for MRI acquisition, GLCM method for MRI texture analysis, and MLR could be indicated for prediction physico-chemical characteristics of loin.  相似文献   
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Galvanostatic electrodeposition mode was employed for the synthesis of new polyaniline and polypyrrole-based composite coatings (PANI/PPY) onto pure zinc electrode. Potentiodynamic polarization, open circuit potential measurements and Electrochemical Impedance Spectroscopy (EIS) were employed to assess the ability of these composite coatings to provide an effective barrier to corrosion in chloride environment. Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) observations were employed to characterize the structure and morphology of the modified electrodes. The coatings deposited galvanostatically at lower current density showed the best quality in terms of protection ability towards aggressive medium. It was found that the new PANI/PPY composite coatings had significantly better properties than single polymer coatings regarding the corrosion protection.  相似文献   
44.
In relative terms, Spanish motorcyclists are more likely to be involved in crashes than other drivers and this tendency is constantly increasing. The objective of this study is to identify the factors that are related to being an offender in motorcycle accidents. A binary logit model is used to differentiate between offender and non-offender motorcyclists. A motorcyclist was considered to be offender when s/he had committed at least one traffic offense at the moment previous to the crash. The analysis is based on the official accident database of the Spanish general directorate of traffic (DGT) for the 2003–2008 time period. A number of explanatory variables including motorcyclist characteristics and environmental factors have been evaluated. The results suggest that inexperienced, older females, not using helmets, absent-minded and non-fatigued riders are more likely to be offenders. Moreover, riding during the night, on weekends, for leisure purposes and along roads in perfect condition, mainly on curves, predict offenses among motorcyclists. The findings of this study are expected to be useful in developing traffic policy decisions in order to improve motorcyclist safety.  相似文献   
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The nucleation and crystallization kinetics of new glasses obtained by melting mixtures of a Spanish carbon fly ash with glass cullet and dolomite slag at 1500°C has been evaluated by a calculation method. These glasses, whose microstructure was examined by TEM carbon replica, were susceptible to controlled crystallization in the 800°–1100°C range. The resulting glass-ceramics developed acicular and branched wollastonite crystals or a network of dendritic pyroxene mixed with anorthite feldspar (SEM and EDX analysis). The time–temperature–transformation curves (processing of the XRD data) showed the crystallization kinetics and the critical cooling rate to be in the 12°–42°C/min range.  相似文献   
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In this work platelet lysate (PL) and adipose‐derived mesenchymal stromal cells (ASCs) seeded on nonwoven fibroin mats were in vitro and in vivo evaluated for tissue regenerative applications. Nonwoven mats obtained by a large scale water entanglement technique were characterized for their physico‐chemical properties. Results indicated a high purity of fibroin fibers, their stability after sterilization process and appropriate technological properties suitable for tissue engineering. Moreover, the scaffolds in vitro supported adhesion and migration of ASCs and the presence of PL improved the cell proliferation. The products were then applied on epithelial/dermal wounds carried out on the dorsal surface of rabbit: the skin reparative process was solved in 9 days, with a completely restitutio ad integrum of the epithelium in animals treated with PL alone; ASCs did not further improve the wound healing. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42942.  相似文献   
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Three new guanylated cyclophosphazenes G1–G3 have been synthesized through the catalytic guanylation of three different bi, tetra and hexa (p-aminophenoxy)-cyclophosphazenes by using N,N’-diisopropylcarbodiimide as guanylating agent, ZnEt2 as catalyst and dry tetrahydrofuran as solvent. The resulting products have been characterized by 1H, 13C{1H} and 31P{1H} NMR spectroscopy. The hexaguanylated cyclophosphazenes exhibit a deep purple colour, unusual for this type of compounds. The electronic structure of these compounds was investigated by carrying out density functional calculations at PBE-D3(BJ)/TZP level of theory. The molecular structural analysis reveals that aromatic rings are stacked and time dependent density functional calculations show that a charge transfer electronic transition occurs between the aromatic rings which absorb light around 500–700 nm. Finally, the catalytic usefulness of guanylated cyclophosphazene compounds G1–G3 has been proven by the preparation of styrene carbonate from the reaction between styrene oxide and carbon dioxide.

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