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111.
Ebrahim Sharifpour Ebrahim Alipanahpour Dil Arash Asfaram Mehrorang Ghaedi Alireza Goudarzi 《应用有机金属化学》2019,33(3)
In the present work, Mn‐doped CuO‐NPs‐AC was prepared by a simple method, characterized using various techniques such as FESEM, EDX, XRD, PSD, and pHpzc and finally used for the adsorption of malachite green (MG) and methyl orange (MO) in a number of single and binary solutions. A series of adsorption experiments were conducted to investigate and optimize the influence of various factors (such as different pH, concentration of MG and MO, adsorbent mass, and sonication time) on the simultaneous adsorption of MG and MO using response surface methodology. Under optimal conditions of pH 10, adsorbent dose of 0.02 g, MG concentration of 30 mg L?1, MO concentration of 30 mg L?1, and sonication time of 4.5 min at room temperature, the maximum predicted adsorption was observed to be 100.0%, for both MG and MO, showing that there is a favorable harmony between the experimental data and model predictions. The adsorption isotherm of MO and MG by Mn‐doped CuO‐NPs‐AC could be well clarified by the Langmuir model with maximum adsorption capacity of 320.69 mg g?1 and 290.11 mg g?1 in the single solution and 233.02 mg g?1 and 205.53 mg g?1 in the binary solution by 0.005 g of adsorbent mass for MG and MO, respectively. Kinetic studies also revealed that both MG and MO adsorption were better defined by the pseudo‐second order model for both solutions. In addition, the thermodynamic constant studies disclosed that the adsorption of MG and MO was likely to be influenced by a physisorption mechanism. Eventually, the reusability of the Mn‐doped CuO‐NPs‐AC after six times showed a reduction in the adsorption percentage of MG and MO. 相似文献
112.
Meccanica - The wastewater of steel production factories consists of a large amount of very small metal particles. The metal particles in this wastewater enter a large sedimentation tank and are... 相似文献
113.
Abbasi Zahra Bahrololoom M. Ebrahim Bagheri Rafat Shariat Mohammad H. 《Journal of Sol-Gel Science and Technology》2017,81(2):523-533
Journal of Sol-Gel Science and Technology - Although dental ceramic restorations are biocompatible, they are not necessarily bioactive. They can be modified by bioactive glasses to exhibit... 相似文献
114.
115.
Mohabat Taghizadeh Mahmoud Ebrahimi Ebrahim Fooladi Mehdi Yoosefian 《Journal of separation science》2022,45(8):1434-1444
A sensitive and straightforward liquid–liquid–liquid microextraction method was developed to preconcentrate and cleanup antidepressants, including mirtazapine, venlafaxine, escitalopram, fluoxetine, and fluvoxamine, from biological samples before analyzing with high-performance liquid chromatography. The essential novelty of this study is using magnetic ionic liquids as the extraction phase in the lumen of hollow fiber and preparing a liquid magnetic stir bar. In this method, polypropylene hollow fiber was utilized as the permeable membrane for the analyte extraction. Six magnetic ionic liquids consisting of the transition metal and rare earth compounds were synthesized and then hollow fiber lumen was injected as acceptor phase to extract the antidepressants. Besides, 3-pentanol as a water-immiscible solvent was impregnated in the hollow fiber wall pores. The effective factors in the method were optimized with the central composition design. The resultant calibration curves were linear over the concentration range of 0.8–400.0 ng mL−1 (R2 ≥ 0.996). The method displayed the proper detection limit (0.11–0.24 ng mL−1), the reasonable limit of quantification (≤0.79 ng mL−1), wide linear ranges, high preconcentration factors (≥294.3), and suitable relative standard deviation (2.31–5.47%) for measuring antidepressant medications. Analysis of human milk and urine samples showed acceptable recoveries of 96.5–103.8% with excellent relative standard deviations lower than 5.95%. 相似文献
116.
Muhammad Amer Latif Sever Silvestru Dragomir Ebrahim Momoniat 《Journal of Applied Analysis & Computation》2017,7(3):795-813
In this paper, a new weighted identity involving harmonically symmetric functions and differentiable functions is established. By using the notion of harmonic symmetricity, harmonic convexity and some auxiliary results, some new Fej\''{e}r type integral inequalities are presented. Applications to special means of positive real numbers are given as well. 相似文献
117.
A numerical multiphase CFD simulation for PEMFC with parallel sinusoidal flow fields 总被引:1,自引:0,他引:1
Journal of Thermal Analysis and Calorimetry - Flow field design has an important role in proton exchange membrane fuel cell (PEMFC) due to its effect on the distribution of pressure, current... 相似文献
118.
Ahmad Shaabani Ebrahim Soleimani Ali Maleki 《Monatshefte für Chemie / Chemical Monthly》2007,138(1):73-76
Summary. The synthesis of 3-aminoimidazo[1,2-a]pyridines and 3-aminoimidazo[1,2-a]pyrazines through a condensation reaction of 2-aminopyridine or 2-aminopyrazine, aldehyde, and alkyl or aryl isocyanide in
high yields at room temperature in the presence of silica sulfuric acid is described. 相似文献
119.
Reduction of barium sulfate by methane was investigated in this work. The thermogravimetric method was used to obtain kinetic parameters of the reaction in the temperature range of 900–975 °C at atmospheric pressure. The kinetics of the reaction has been studied both in the absence and presence of zinc oxide as a catalyst. The conversion–time data have been interpreted by using the grain model, and the effect of catalyst on the kinetic parameters has been elucidated. It was found that zinc oxide acted as fairly strong catalyst for the reaction, especially at higher temperatures. At about 975 °C the reaction rate constant was increased more than 7 times by using 2% of zinc oxide. This enhancement in the rate constant is valuable for industries. 相似文献
120.
Milad Sheydaei Milad Edraki Ebrahim Alinia-Ahandani Enayat Ollah Moradi Rufchahi Pegah Ghiasvandnia 《高分子科学杂志,A辑:纯化学与应用化学》2021,58(1):52-58
Abstract In this work, two polysulfide polymers were synthesized using aromatic organic monomer (α,α′-dichloro-p-xylene) and sodium disulfide (Na2S2) and sodium tetrasulfide (Na2S4) aqueous monomers. Then, the curing process of the polymers was carried out at 170° C using a rheometer. The structural characteristics of synthesized and cured samples were identified by Raman and Fourier transform infrared (FT-IR) spectroscopies. Also, morphological and thermophysical properties of samples were studied by using the X-ray diffraction (XRD) and differential scanning calorimetry (DSC), respectively. Moreover, the molecular weight of the synthesized samples was determined by proton nuclear magnetic resonance (1H NMR). Furthermore, the mechanical properties and hardness of the samples were investigated by tensile test and Shore A. The results showed that in the noncured samples during the increase of sulfur in the polymer structure, solubility was increased whereas it decreased the hardness, melting point (Tm ) and glass transition temperature (Tg ) of polymers. But in cured samples, hardness and Tg increase by increasing sulfur and the mechanical properties also improved. This is due to the increase in crosslinks. Also, Tm and solubility are not observed due to the formation of crosslinks. 相似文献