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91.
Ehsan Karimi Meisam Habibi Mahdi Ebrahimi Ali Mehrafarin Farahnaz Khalighi-Sigaroodi 《Natural product research》2018,32(16):1991-1995
The antioxidant activities of crude extract fractions using Hexane, Chloroform, Ethyl Acetate, Butanol and Water of Clematis orientalis and Clematis ispahanica were investigated. 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay and the ferric reducing/antioxidant potential (FRAP) were used to evaluate the antioxidant capacity. The total phenolics were found to be 4.37–9.38 and 1.32–11.37 mg gallic acid equivalents (GAE)/g in different fractions for C. orientalis and C. ispahanica, respectively. The ethyl acetate fraction of C. orientalis and chloroform fraction of C. ispahanica showed the highest DPPH and FRAP activities at a concentration of 300 μg/mL. The predominant phenolic compounds identified by HPLC in C. orientalis were Resorcinol (603.5 μg/g DW) in chloroform fraction and Ellagic acid (811.7 μg/g DW) in chloroform fraction of C. ispahanica. 相似文献
92.
Ayoub Taavoni-Gilan Ehsan Taheri-Nassaj Mojtaba Shamsipur 《Journal of the Iranian Chemical Society》2018,15(12):2759-2769
Nanostructured TiO2/ZrO2 composite membranes with varying compositions were obtained by sol–gel technique. The influence of 0–30 mol% zirconia doping on microstructure, water permeability, photocatalytic and physical separation properties, removal of methyl violet of textile industries wastewater and thermal and mechanical stability of titania/zirconia composite membranes was described. Firstly, alumina supports were coated with TiO2 intermediate layers using the colloidal sol–gel route. The TiO2/ZrO2 composite sols were prepared via a polymeric sol–gel method and dip-coated on TiO2 intermediate layer. The samples were characterized by DLS, TG-DTA, XRD, FTIR, BET-BJH, UV–visible, SEM, TEM and AFM. It was shown that zirconia retards the phase transformation of anatase to rutile until at least 700 °C. The minimum pore size and maximum surface area obtained were 1.2 nm and 153 m2/g, respectively, attributed to the sample with 20 mol% zirconia. The mechanical strength of titania membranes was significantly improved by addition of zirconia. The most methyl violet removal efficiency obtained, with and without UV-irradiation, is 80.8 and 72.6%, respectively, attributed to the sample with 20 mol% zirconia. 相似文献
93.
The [3+3] cyclization of 1,3-bis-silyl enol ethers with 1,1-diacylcyclopentanes allows a convenient synthesis of spiro[5.4]decenones. Treatment of these compounds with trifluoroacetic acid (TFA) afforded a great variety of bicyclo[4.4.0]deca-1,4-dien-3-ones containing an angular alkyl group. This core structure occurs in a number of pharmacologically relevant natural products. 相似文献
94.
Ehsan Zahedi 《Comptes Rendus Chimie》2013,16(2):189-194
Adsorption of nitrogen dioxide on the exterior surface of C30B15N15 through B atom of adsorbent is studied using the DFT-B3LYP/6-31G* level. Independent to the orientation, the NO2 molecule presents strong chemisorption with large charge transfer from C30B15N15 to adsorbed gas. NBO (natural electron configuration of adsorbing B atom), AIM analysis and spin density distributions indicate that the chemisorption of NO2 on the C30B15N15 in all studied complexes are covalent in nature. 相似文献
95.
Maithani Rajesh Kumar Anil Gholamali Zadeh Peyman Safaei Mohammad Reza Gholamalizadeh Ehsan 《Journal of Thermal Analysis and Calorimetry》2020,139(2):1195-1212
Journal of Thermal Analysis and Calorimetry - A study was conducted to enhance the thermo-hydraulic performance of a rectangular solar air passage with integrated spherical-shaped turbulence... 相似文献
96.
Pourhadi Ehsan Khrennikov Andrei Yu. Oleschko Klaudia de Jesús Correa Lopez María 《Journal of Fourier Analysis and Applications》2020,26(4):1-12
We consider the pointwise convergence problem for the solution of Schrödinger-type equations along directions determined by a given compact subset of the real line. This problem contains Carleson’s problem as the simplest case and was studied in general by Cho et al. We extend their result from the case of the classical Schrödinger equation to a class of equations which includes the fractional Schrödinger equations. To achieve this, we significantly simplify their proof by completely avoiding a time localization argument. 相似文献
97.
98.
99.
Ehsan Farsouni Eydi Mohamad Reza Khosravi-Nikou 《Journal of Dispersion Science and Technology》2019,40(3):453-463
A commercial synthetic zeolite (Na-ZSM-5) was modified with an organic surfactant, HDTMA-Br. Then both unmodified and modified zeolite (SMZ-100) were tested to adsorb Benzene, Toluene, Ethylbenzene and Xylene (BTEX) compounds from water solution. Adsorption tests were done in batch conditions at the ambient temperature (20?°C) and pressure. Adsorbents were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), N2 adsorption-desorption isotherms and field emission scanning electron microscopy (FE-SEM) and characterization results proved the existence of surfactant on the surface of the adsorbent. In all cases, the modified zeolite sample, because of increasing the hydrophobicity of its surface, exhibited higher adsorption capacity in comparison with unmodified zeolite. Also, for each adsorbent, the adsorption capacity follows the order: E?>?X?>?T?>?B. In equilibrium experiments, Langmuir isotherm model fitted the equilibrium data better than the Freundlich model. In kinetic experiments, the pseudo-second order model described the kinetic data better than the other models. 相似文献
100.
Using DFT methods, the electronic properties and the first hyperpolarizabilities of porphyrin‐like porous C24N24 fullerene decorated with (Li3O)n = (1–5) have been systematically investigated. It is found that Li3O molecules can effectively be adsorbed over N4 cavities of C24N24 with high interaction energies. This interaction is found to narrow the HOMO‐LUMO gap and work function values of C24N24. Thus its electronic properties are strongly sensitive to interaction with the Li3O molecules. Indeed, compared with the sole parent C24N24 fullerene, (Li3O)n = (1–5)@C24N24 possess large first hyperpolarizabilities (β0 ). Obviously, the Li3O superalkali chemisorbed over C24N24 fullerene exhibit not only excellent stability but also large first hyperpolarizability. Therefore, they are expected to be potential innovative candidates for excellent electro‐optical materials. 相似文献