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排序方式: 共有514条查询结果,搜索用时 31 毫秒
31.
Mohamed Latoui Bahar Aliakbarian Alessandro A. Casazza Mongi Seffen Attilio Converti Patrizia Perego 《Food and Bioproducts Processing》2012,90(4):748-754
The primary objective of this study was to valorized Vitex agnus-castus residues in terms of phenolic compounds. The effects of extraction time (30–360 min), solid to liquid ratio (0.1–0.3 gDryBiomass/mlSolvent), type of solvent and different tissue types (leave, roots and seeds) on total polyphenols, o-diphenols, total flavonoids and anthocyanins were evaluated. The highest total polyphenol (31.5 mgCaffeicAcidEquivalent/gDryBiomass) and o-diphenol (12.4 mgCaffeicAcidEquivalent/gDryBiomass) contents were obtained from methanolic extract of leaves after 180 min using a solid/liquid ratio of 0.1 gDryBiomass/mlSolvent, while total flavonoids, reached a maximum value of 19.4 mgCatechinEquivalent/gDryBiomass after 360 min under the same conditions. Roots of V. agnus-castus were found to be a good source of anthocyanins with the highest yield of 0.62 mgMalvidinEquivalent/gDryBiomass using ethanol as a solvent (180 min and 0.2 gDryBiomass/mlSolvent). The maximum antiradical power (178.5 μlextract/μgDPPH) was exhibited by the methanolic leave extract obtained after 360 min at solid/liquid ratio of 0.3 gDryBiomass/mlSolvent. 相似文献
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Andrea Pietro Reverberi Patrizia Bagnerini Luigi Maga Agostino Giacinto Bruzzone 《International Journal of Heat and Mass Transfer》2008,51(21-22):5327-5332
A numerical study on a non-linear hyperbolic diffusion equation is proposed. The Hartree hybrid method combining finite difference techniques with the method of characteristics is used in the presence of discontinuities between initial and boundary conditions. The technique proved to be an useful tool to overcome oscillation problems and spurious solutions in case of strong non-linearities related to both attractive or repulsive interactions between diffusing species. Two different expressions for the diffusion coefficient are used in order to compare our results with the ones obtained in previous studies relying upon the Laplace transform technique and the MacCormack predictor–corrector method. Finally, an analytic approach based on the singular surface theory is proposed to motivate the numerical results and to clarify some controversial aspects concerning the penetration depth of a diffusive front in the presence of interactions. 相似文献
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Natale Francesco; Antinucci Francesco; Spinozzi Giovanna; Potí Patrizia 《Canadian Metallurgical Quarterly》1986,100(4):335
Several investigators have reported the achievement of Stage 6 object concept in a number of species of nonhuman primates. Because Stage 6 object concept implies a capacity for mental representation, such an achievement would demonstrate the presence of a crucial capacity in nonhuman primate cognition. There are, it is suggested, problems in the way nonhuman primates have been tested for Stage 6 object concept (i.e., that the tasks employed could be solved in nonrepresentational ways). The present study attempted to differentiate between representational and nonrepresentational responses in the typical task used for testing Stage 6 object concept (following the invisible displacements of an object). The performance of 2 22-mo-old Ss, a Japanese macaque and a gorilla, was compared. It was found that only the gorilla solved the task with the use of mental representation. The macaque consistently tried to solve the task by employing practical, nonrepresentational strategies. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Francesco Sannicolò Simona Rizzo W?odzimierz Kutner Krzysztof Noworyta Valentina Bonometti Luigi Falciola Patrizia R. Mussini Marco Pierini 《Electrochimica acta》2010,55(27):8352-8364
Novel thiophene-based oligomer, 2,2′-bis(2,2′-bithiophene-5-yl)-3,3′-bithianaphthene (TX), was designed and synthesized, and its electrochemical and spectral properties characterised. TX was readily polymerised electrochemically to form well organized conducting homopolymer films on various solid electrode substrates. Moreover, it was successfully used for deposition by electropolymerisation of electrochemically active thin films of co-polymers with three different monomers of functionalised bis(2,2′-bithienyl)methane derivatives. It appeared that TX was an effective crosslinker and 3D promoter in these electropolymerisations involving co-monomers intrinsically showing limited aptitude for the electropolymerisation or forming polymer films of low conductivity. This attractive TX ability stems from combination of its (i) high conjugation efficiency in each of the two planar moieties, (ii) intrinsic 3D structure on account of the presence of the central node, and (iii) intrinsic regioselectivity in electropolymerisation on account of the positions of the two available free α-thiophene sites. 相似文献
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Characterization of a Combined Treatment with Alpha‐Lipoic Acid for the Control of Enzymatic Browning in Fresh‐Cut Golden Delicious Apples
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