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11.
Using gamma irradiation for the recovery of anthocyanins from grape pomace   总被引:1,自引:0,他引:1  
This research investigated the effect of gamma irradiation from 0 to 9 kGy, packaging in air or under vacuum, or in combination with other treatments for enhancing anthocyanin extraction from grape pomace. Results indicate that the irradiation at 6 kGy and packaging in the presence of a low concentration of sodium metabisulfite yielded the highest value of anthocyanin extraction.  相似文献   
12.
Suaeda fruticosa Forssk. Ex J.F.Gmel is traditionally used for inflammatory and digestive disorders, as a carminative, and for diarrhea. This plant is widely distributed in Asia, Africa, and the Mediterranean region. Aqueous methanolic extract of S. fruticosa (Sf.Cr) was prepared and screened for phytoconstituents through qualitative and GC-MS analysis. Quantification of total phenolic and flavonoid contents was performed, while antioxidant capacity was determined by DPPH, CUPRAC, FRAP, and ABTS assays. The gastroprotective activity was assessed in an ethanol-induced ulcer model. Gastric secretory parameters and macroscopic ulcerated lesions were analyzed and scored for ulcer severity. After scoring, histopathology was performed, and gastric mucus contents were determined. Oral pre-treatment of Sf.Cr demonstrated significant gastroprotection. The gastric ulcer severity score and ulcer index were reduced while the %-inhibition of ulcer was increased dose-dependently. The Sf.Cr significantly elevated the pH of gastric juice, while a decrease in total acidity and gastric juice volume was observed. Histopathology demonstrated less oedema and neutrophil infiltration in gastric mucosa of rats pre-treated with the Sf.Cr in comparison to ethanol-intoxicated animals. Furthermore, the gastric mucus contents were increased as determined by alcian blue binding. Sf.Cr showed marked gastroprotective activity, which can be attributed to antioxidant, antisecretory, and cytoprotective effects.  相似文献   
13.
In this paper we prescribe a fourth order conformal invariant (the Paneitz curvature) on the n-spheres, with n∊{5,6}. Using dynamical and topological methods involving the study of critical points at infinity of the associated variational problem, we prove some existence results. Mathematics Subject Classifications (2000): 35J60, 53C21, 58J05, 35J30.  相似文献   
14.
In this paper, we investigate the use of low-discrepancy sequences to generate an initial population for population-based optimization algorithms. Previous studies have found that low-discrepancy sequences generally improve the performance of a population-based optimization algorithm. However, these studies generally have some major drawbacks like using a small set of biased problems and ignoring the use of non-parametric statistical tests. To address these shortcomings, we have used 19 functions (5 of them quasi-real-world problems), two popular low-discrepancy sequences and two well-known population-based optimization methods. According to our results, there is no evidence that using low-discrepancy sequences improves the performance of population-based search methods.  相似文献   
15.
Ten archaeological Punic make-up samples from Tunisia dating from the 4th to the 1st centuries BC were analysed by several techniques including Raman microscopy and synchrotron X-ray diffraction in order to determine their compositions. Eight samples were red and found to contain either quartz and cinnabar or quartz and haematite. The remaining two samples were pink, the main diffracting phase in them being quartz. Examination of these two samples by optical microscopy and by illumination under a UV lamp suggest that the pink dye is madder. These findings reveal the identities of the materials used by Carthaginians for cosmetic and/or ritual make-up purposes. PACS 82.80.Gk; 61.10.Nz; 41.60Ap  相似文献   
16.
β‐Keto‐amides react with 2‐dimethylaminomethylene‐1,3‐bis(dimethylimonio)propane diperchlorate salt to give the corresponding 3‐acetyl‐5‐formylpyridin‐2‐ones. The annulation reactions proceed with excellent yields.  相似文献   
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18.
In this article we consider the following fourth order mean field equation on smooth domain Ω?R4:
  相似文献   
19.
Carbon-13 chemical shifts and the POC, POCC, PNC and PNCC coupling constants of 18 compounds containing the amine moiety, and with the general formula Y2P(X)NHR [Y=C2H5O, C6H5O, CH2O, Y2=1,2-dioxybenzene; X = O or S; R = H, CH3, C2H5, PhCH2CH2, (CH3)2CH, C(CH3)3, C6H11, C6H5, C6H5NH] have been determined. The Y2P(X) group shows a sterically induced effect on the amine moiety; the 13C chemical shift of the Y group is, however, almost unaffected on replacing P(O) by a P(S) group.  相似文献   
20.
Yossri  W.  Bouma  A.  Ben Ayed  S.  Vasconcellos  R.  Abdelkefi  A. 《Nonlinear dynamics》2022,107(2):1569-1594
Nonlinear Dynamics - The effects of the aerodynamic loads on continuous wing-based systems can be represented using a quasi-steady or a fully unsteady reduced-order modeling. Frequently, the...  相似文献   
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