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81.
Nili-Ahmadabadi Mahdi Nematollahi Omid Fatehi Mostafa Cho Dae Seung Kim Kyung Chun 《显形杂志》2020,23(4):591-603
Journal of Visualization - Airfoils are mostly inefficient in their off-design conditions. In order to improve the aerodynamic performance of airfoils in these conditions, using an optimized cavity... 相似文献
82.
Mostafa El Khomsi Hamada Imtara Mohammed Kara Anouar Hmamou Amine Assouguem Brahim Bourkhiss Mahmoud Tarayrah Mashail N. AlZain Nurah M. Alzamel Omar Noman Driss Hmouni 《Molecules (Basel, Switzerland)》2022,27(2)
Anchusa italica Retz has been used for a long time in phytotherapy. The aim of the present study was to determine the antioxidant and antibacterial activities of extracts from the leaves and roots of Anchusa italica Retz. We first determined the content of phenolic compounds and flavonoids using Folin–Ciocalteu reagents and aluminum chloride (AlCl3). The antioxidant activity was determined using three methods: reducing power (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant capacity (TAC). The antimicrobial activity was investigated against four strains of Escherichia coli, two strains of Klebsiella pneumoniae and coagulase-negative Staphylococcus, and one fungal strain of Candida albicans. The results showed that the root extract was rich in polyphenols (43.29 mg GAE/g extract), while the leave extract was rich in flavonoids (28.88 mg QE/g extract). The FRAP assay showed a strong iron reduction capacity for the root extract (IC50 of 0.11 µg/mL) in comparison to ascorbic acid (IC50 of 0.121 µg/mL). The DPPH test determined an IC50 of 0.11 µg/mL for the root extract and an IC50 of 0.14 µg/mL for the leaf extract. These values are low compared to those for ascorbic acid (IC50 of 0.16 µg/mL) and BHT (IC50 0.20 µg/mL). The TAC values of the leaf and root extracts were 0.51 and 0.98 mg AAE/g extract, respectively. In vitro, the extract showed inhibitory activity against all strains studied, with diameters of zones of inhibition in the range of 11.00–16.00 mm for the root extract and 11.67–14.33 mm for the leaf extract. The minimum inhibitory concentration was recorded for the leaf extract against E. coli (ATB:57), corresponding to 5 mg/mL. Overall, this research indicates that the extracts of Anchusa italica Retz roots and leaves exert significant antioxidant and antibacterial activities, probably because of the high content of flavonoids and polyphenols. 相似文献
83.
Rooha Khurram Zaib Un Nisa Aroosa Javed Zhan Wang Mostafa A. Hussien 《Molecules (Basel, Switzerland)》2022,27(4)
This study describes the preparation of graphitic carbon nitride (g-C3N4), hematite (α-Fe2O3), and their g-C3N4/α-Fe2O3 heterostructure for the photocatalytic removal of methyl orange (MO) under visible light illumination. The facile hydrothermal approach was utilized for the preparation of the nanomaterials. Powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX), and Brunauer–Emmett–Teller (BET) were carried out to study the physiochemical and optoelectronic properties of all the synthesized photocatalysts. Based on the X-ray photoelectron spectroscopy (XPS) and UV-visible diffuse reflectance (DRS) results, an energy level diagram vs. SHE was established. The acquired results indicated that the nanocomposite exhibited a type-II heterojunction and degraded the MO dye by 97%. The degradation ability of the nanocomposite was higher than that of pristine g-C3N4 (41%) and α-Fe2O3 (30%) photocatalysts under 300 min of light irradiation. The formation of a type-II heterostructure with desirable band alignment and band edge positions for efficient interfacial charge carrier separation along with a larger specific surface area was collectively responsible for the higher photocatalytic efficiency of the g-C3N4/α-Fe2O3 nanocomposite. The mechanism of the nanocomposite was also studied through results obtained from UV-vis and XPS analyses. A reactive species trapping experiment confirmed the involvement of the superoxide radical anion (O2•−) as the key reactive oxygen species for MO removal. The degradation kinetics were also monitored, and the reaction was observed to be pseudo-first order. Moreover, the sustainability of the photocatalyst was also investigated. 相似文献
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The spiro-compound 3′H-spiro[indole-3,2′-[1,3]benzothiazole-2(1H)-one (IBTH2) was synthesized and its structure was determined using spectroscopic techniques (FTIR, 1H NMR and mass) and X-ray crystallography. This ligand possesses different centers for coordination. Reactions of [M(CO)6], M = Cr, Mo or W with IBTH2 in THF under reduced pressure were studied. For chromium a complex with molecular formula [Cr(ITP)2] was isolated; where ITP is the opened form of the ligand which occurred through Cspiro–S bond, while [Mo(CO)5(IBTH2)] and [W(CO)5(IBTH2)] were isolated from the reaction of IBTH2 with molybdenum and tungsten carbonyls, respectively. All complexes were characterized by elemental analysis, IR, mass and 1H NMR spectroscopy. The biological activity of the ligand and its complexes were studied and compared with the parent compound isatin. 相似文献
88.
Mohsen M. Mostafa Rafaat M. El-Shazly Tawfik H. Rakha Mohamed H. Abdel-Rahman 《Transition Metal Chemistry》2002,27(2):237-237
Other Index
Forthcoming articles 相似文献89.
90.
MostafaADIMY MostafaLAKLACH KhalilEZZINBI 《数学学报(英文版)》2004,20(5):933-942
In this work, we are concerned with a general class of abstract semilinear autonomous functional differential equations with a non-dense domain on a Banach space. Our objective is to study, using the Crandall-Liggett approach, the solutions as a semigroup of non-linear operators. 相似文献