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81.
Fahd Kandsi Raffaele Conte Mohamed Marghich Fatima Zahra Lafdil Mohamed F. Alajmi Mohamed Bouhrim Hamza Mechchate Christophe Hano Mohammed Aziz Nadia Gseyra 《Molecules (Basel, Switzerland)》2021,26(23)
Dysphania ambrosioides (L.) Mosyakin and Clemants is an annual or ephemeral perennial herb used traditionally in the Mediterranean region in folk medicine to treat various illnesses, including those related to the digestive system. This study aims to assess the antispasmodic, myorelaxant, and antioxidant effects of D. ambrosioides flower hydroethanolic extract and its chloroform and ethyl acetate fractions in a comparative study to evaluate the result of the extraction type on the potential activity of the extract. Both rat and rabbit jejunum were used to evaluate the antispasmodic and myorelaxant effect, while the antioxidant effect was evaluated using DPPH, a ferric reducing power assay, and a beta-carotene bleaching test. LC/MS-MS analysis was carried out to reveal the composition of the different types of extract. Following the results, the hydroethanolic extract showed a significant myorelaxant effect (IC50 = 0.39 ± 0.01 mg/mL). Moreover, it was shown that the hydroethanolic extract demonstrated the best antispasmodic activity (IC50 = 0.51 ± 0.05 mg/mL), followed by the ethyl acetate (IC50 = 4.05 ± 0.32 mg/mL) and chloroform (IC50 = 4.34 ± 0.45 mg/mL) fractions. The antioxidant tests showed that the hydroethanolic extract demonstrated high antioxidant activity, followed by the ethyl acetate and chloroform fractions. The LC/MS-MS analysis indicates that the plant extract was rich in flavonoids, to which the extract activity has been attributed. This study supports the traditional use of this plant to treat digestive problems, especially those with spasms. 相似文献
82.
Ragaa A. Hamouda Amera Abd El Latif Ebtihal M. Elkaw Amenah S. Alotaibi Asma Massad Alenzi Hanafy A. Hamza 《Molecules (Basel, Switzerland)》2022,27(5)
There is a very vital antioxidant extracted from microgreen alga. Chlorella vulgaris has major advantages and requires high yield worldwide. Some microalgae require vitamins for their growth promotion. This study was held to determine the impact of different vitamins including Thiamine (B1), Riboflavin (B2), Pyridoxine (B6), and Ascorbic acid (c) at concentrations of 0.02, 0.04, 0.06, and 0.08 mg/L of each. Each vitamin was added to the BG11 growth medium to determine the effect on growth, total carbohydrate, total protein, pigments content, antioxidant activities of Chlorella vulgaris. Moreover, antitumor effects of methanol extract of C. vulgaris without and with the supplement of thiamine against Human prostate cancer (PC-3), Hepatocellular carcinoma (HEPG-2), Colorectal carcinoma (HCT-116) and Epitheliod Carcinoma (Hela) was estimated in vitro. C. vulgaris supplemented with various vitamins showed a significant increase in biomass, pigment content, total protein, and total carbohydrates in comparison to the control. Thiamine was the best vitamin influencing as an antioxidant. C. vulgaris supplemented with thiamine had high antitumor effects in vitro. So, it’s necessary to add vitamins to BG11 media for enhancement of the growth and metabolites. 相似文献
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A. Louhadj Mohamed Ghezali F. Badi Noureddine Mehnane Youcef Cherchab Bouhalouane Amrani Hamza Abid Nadir Sekkal 《Superlattices and Microstructures》2009,46(3):435-442
Using the plane wave version of the full potential linear muffin-tin orbital (FPLMTO) method, which enables an accurate treatment of the interstitial regions, the electronic properties of ScN, YN, LaN and GdN rocksalt/rocksalt superlattices are calculated. It is found that apart from YN/ScN, all the other superlattices have negative bandgaps. However, it is shown that these systems can be semiconductors if a correction is made to the local density approximation (LDA). 相似文献
85.
M. I. Hussein K. Hamza G. M. Hulbert K. Saitou 《Waves in Random and Complex Media》2007,17(4):491-510
The spatial distribution of material phases within a periodic composite can be engineered to produce band gaps in its frequency spectrum. Applications for such composite materials include vibration and sound isolation. Previous research focused on utilizing topology optimization techniques to design two-dimensional (2D) periodic materials with a maximized band gap around a particular frequency or between two particular dispersion branches. While sizable band gaps can be realized, the possibility remains that the frequency bandwidth of the load that is to be isolated might exceed the size of the band gap. In this paper, genetic algorithms are used to design squared bi-material unit cells with a maximized sum of band-gap widths, with or without normalization relative to the central frequency of each band gap, over a prescribed total frequency range of interest. The optimized unit cells therefore exhibit broadband frequency isolation characteristics. The effects of the ratios of contrasting material properties are also studied. The designed cells are subsequently used, with varying levels of material damping, to form a finite vibration isolation structure, which is subjected to broadband loading conditions. Excellent isolation properties of the synthesized material are demonstrated for this structure. 相似文献
86.
A. A. Hamza M. A. Mabrouk W. A. Ramadan M. A. Shams-Eldin 《Optics Communications》2001,200(1-6):131-138
The core–cladding refractive index difference Δn and the index gradient profile parameter of the graded index (GR-IN) optical fibre has been determined. The curve representing the real path, in the core region, due to refraction of the beam and the change in the exit wavefront are considered. Multiple-beam Fizeau fringes and two-beam interference Pluta polarizing microscope, are used for this investigation. A new method, based on a derived mathematical expression, is used with a prepared computer program to estimate the fringe shift inside GR-IN of the fibre core. The estimated and experimental values of the fringe shift, along the core radius, are used to obtain the refractive index profile of the optical fibre. A comparison between the new method and a previous model considering the refraction has been shown. Microinterferograms are given for illustrations. 相似文献
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89.
Anis Hamza Fakeeh Muhammad Awais Naeem Wasim UllahKhan Ahmed Elhag Abasaee Ahmed Sadeq Al-Fatesh 《化学物理学报》2014,27(2):214-220
用浸渍法制备γ-Al2O3负载的Ni-Mn双金属催化剂.在500~700 oC按照17:17:2的CO2/CH4/N2比例,以36 mL/min的载气流速进行甲烷二氧化碳重整反应, 利用甲烷二氧化碳的转化率、生成的合成气H2/CO比例以及长期稳定性等指标评价了催化剂的催化性能. 实验表明, 添加Mn提高催化性能并使双金属催化剂的稳定性更高, 比单金属催化剂更好地抑制焦炭生成,Mn最合适的添加量0.5wt% .通过BET、CO2-TPD、TGA、XRD、SEM、EDX和FTIR各种技术对催化剂进行了表征. 相似文献
90.
Mohammed F. Hamza Mohamed G. Mahfouz Adel A.-H. Abdel-Rahman 《Journal of Dispersion Science and Technology》2013,34(11):1544-1551
Nitrogenous compounds are the most widely used in solid phase extraction due to its low cost, easy convertible to many functional groups. These have large adsorptive capacity toward heavy metal ions as rare earth elements (REEs) and uranium with ability for recovering from low concentrate solutions. Synthesis of resins were carried out by polymerization of acrylonitrile with divinyl benzene as crosslinker. Treatment of the resulted precipitate with hydrazine hydrate in ethanol produce hydrazinyl methyl amine which has high chelating capacity toward uranyl ions. 1,3,4-Thiadiazol-2(3H)-thion derivative was yielded by reaction of hydrazinyl amine with carbon disulfide in methanol. This reaction carried out in the presence of methyl benzoate and dioctyl phthalate as pore producing solvent which used to improve physical properties and adsorptive character of the resins. Optimization on the two resins during loading and elution were carried out using solution with different concentrations. The optimum factors during adsorption and elution were recognized. 相似文献