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Teimuri-Mofrad Reza Ahadzadeh Iraj Gholamhosseini-Nazari Mahdi Esmati Somayeh Shahrisa Aziz 《Research on Chemical Intermediates》2018,44(4):2913-2927
Research on Chemical Intermediates - In this research, for the first time, aminonaphthol derivatives were introduced as efficient corrosion inhibitors. A linear polarization method was employed to... 相似文献
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Somayeh Hashemi-Uderji Mohammad Abdollahi-Alibeik 《Journal of the Iranian Chemical Society》2018,15(8):1709-1719
A three-component process for the one-pot synthesis of 6-amino-4-aryl-5-cyano-3-methyl-1-phenyl-1,4-dihydropyrano[2,3-c]pyrazoles by the reaction of aldehydes, 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, and malononitrile in the presence of FSM-16-SO3H as an efficient mesoporous catalyst. The FSM-16-SO3H was prepared and characterized by SEM, XRD, BET, and FT-IR techniques. The advantages of the presented method are high yields, short reaction times, easy purification of products, easy work-up, and reusability of the catalyst. 相似文献
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Sima Ahmadi Mohammad Taghi Hamed Mosavian Somayeh Heydari 《Journal of the Iranian Chemical Society》2018,15(11):2605-2614
A rapid and simple approach for the preconcentration and determination of catechin from pistachio green hull samples has been proposed by surfactant-assisted dispersive liquid–liquid microextraction followed by UV–Vis spectrophotometry (SADLLME/UV–Vis). This method involved the formation of a catechin complex with cetylpyridinium chloride (CPC) as cationic surfactant, and subsequently, DLLME was applied to extract the catechin–CPC complex into chloroform. Different parameters affected the extraction efficiency were optimized by central composite design (CCD) and response surface methodology (RSM). In optimum condition, the calibration curve was linear in the range of 0.4–5 µg mL??1 of catechin with correlation coefficient of 0.9982. The relative standard deviation based on five replicated analyses of 1 µg mL??1 catechin was 1.85%. The proposed method was successfully applied for preconcentration and determination of trace amounts of catechin in pistachio hull samples. 相似文献
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Sadeghi-Kohan Somayeh Hellebrand Sybille Wunderlich Hans-Joachim 《Journal of Electronic Testing》2021,37(5-6):715-728
Journal of Electronic Testing - Safety-critical systems have to follow extremely high dependability requirements as specified in the standards for automotive, air, and space applications. The... 相似文献
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Saeed Rayati Saeed Zakavi Somayeh H. Motlagh Vahid Noroozi Maryam Razmjoo Andrzej Wojtczak Anna Kozakiewicz 《Polyhedron》2008
X-ray crystallographic studies have shown that the free base β-tetra-brominated meso-tetraphenylporphyrin (H2TPPBr4) has a slightly ruffled structure with the dihedral angles of 70.1–79.2° between the phenyl groups and the porphyrin mean plane. The N(pyrrole)–N(pyrrolenine) distance is very similar to that of the standard planar porphyrins. The decreased N–H bond length of H2TPPBr4 with respect to that of meso-tetraphenylporphyrin (H2TPP) seems to be due to the weaker intramolecular hydrogen bond of the former relative to the latter caused by the electron-withdrawing effects of the β-bromine substituents. The large red shifts of the Soret and Q(0,0) bands of H2TPPBr4 in comparison with those of H2TPP, in spite of the nearly planar porphyrin core of the compound, also may be explained on the basis of the electron-withdrawing effects of the bromine atoms. Oxidation of styrene, the para-substituted derivatives and cyclooctene with tetrabutylammonium oxone in the presence of catalytic amounts of β-tetra-brominated meso-tetraphenylporphyrinatomanganese(III) acetate immediately gives the epoxide as the sole product. Terminal double bonds and unconjugated ones are less reactive than the conjugated double bonds and show lower selectivities. Catalytic activity of the electron-deficient Mn(H2TPPBr4)OAc dramatically depends on the Co-catalytic activity of the nitrogen donors as the axial base. The best axial bases are the nitrogenous donors with mixed σ- and π-donor ability to the metal centre. 相似文献
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In this work, TiO2 and doped TiO2 photocatalysts (Fe/TiO2 and Cu/TiO2) were synthesized by the sol–gel method. The main objective of this study was to investigate the influence of dopants on the structure, morphology, and activity of the catalysts in powder and immobilized states. XRF, XRD, and SEM methods were used to characterize the catalysts. The structure and phase distribution of the nanocrystalline powders were identified by XRD. Nanoparticles crystallite size and the degree of crystallinity were affected by doping. The anatase contents of catalysts were achieved as follows: TiO2 (5.89 %) < Fe/TiO2 (42.17 %) < Cu/TiO2 (70.28 %). It was indicated that the activity of the catalysts strongly depends on the anatase content. Under the same circumstances, copper-modified TiO2 exhibited a twofold higher photocatalytic activity compared with TiO2. The nanostructured catalysts were immobilized on light expanded clay aggregate (LECA) granules in order to investigate the effect of a novel support on the activity of the catalysts. Morphological changes are recognizable in the SEM images. Activity tests indicated that the best catalytic performance was assigned to Cu/TiO2/LECA. After 120 min of irradiation, 61 % degradation of phenol in synthetic wastewater was achieved. The high photocatalytic activity of Cu/TiO2/LECA confirms that LECA is as an excellent support. 相似文献
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Velinda Calvert Somayeh Mashayekhi Mohsen Razzaghi 《Mathematical Methods in the Applied Sciences》2016,39(5):1268-1284
In this paper, a numerical method for solving Lane‐Emden type equations, which are nonlinear ordinary differential equations on the semi‐infinite domain, is presented. The method is based upon the modified rational Bernoulli functions; these functions are first introduced. Operational matrices of derivative and product of modified rational Bernoulli functions are then given and are utilized to reduce the solution of the Lane‐Emden type equations to a system of algebraic equations. Illustrative examples are included to demonstrate the validity and applicability of the technique. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Mohammad Saeid Hosseini Somayeh Khorashahi Navid Hosseini 《Journal of fluorescence》2016,26(3):867-874
The CdSe quantum dots (QDs) capped with 2-mercaptonicotinic acid (H2MN) were prepared through a controllable process at 80 °C. The prepared QDs were characterized by XRD, TEM, IR, UV–Vis and fluorescence (FL) techniques. It was found that the QDs were nearly mono-disperse with the diameters in the range of 8–10 nm. These QDs are capable to exhibit strong FL even in concentrated acidic media. They exhibit an enhanced fluorescence in the presence of Cr(VI), which was used for the determination of Cr(VI) in water samples. The linear range was found to be 1?×?10?7–6.0?×?10?6 M with the RSD and DL of 0.92 % and 5?×?10?8 M, respectively. Except that Ca2+ and Fe3+ which can be eliminated through a simple precipitation process, the other co-existent ions present in natural water were not interfered. The recoveries obtained for the added amounts of Cr(VI) were in the range of 96.9–103.2 %, which denote on application of the method, satisfactorily. 相似文献