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81.
Fatahian Hossein Jouybari Nima Fallah Nimvari Majid Eshagh Fatahian Esmaeel Zhang Wennan 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12919-12931
Journal of Thermal Analysis and Calorimetry - The present study deals with the numerical simulation of turbulent flow in a Z-type manifold in which the fluid is distributed via nine distribution... 相似文献
82.
A novel Pd−NHC functionalized metal–organic framework (MOF) based on MIL-101(Cr) was synthesized and used as an efficient heterogeneous catalyst in the C-C bond formation reactions. Using this heterogeneous Pd catalyst system, the Suzuki−Miyaura coupling reaction was accomplished well in water, and coupling products were obtained in good to excellent yields in short reaction time. The Pd−NHC−MIL-101(Cr) was characterized using some different techniques, including Fourier transform-infrared, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy, inductively coupled plasma and elemental analysis. The microscopic techniques showed the discrete octahedron structure of MIL-101(Cr), which is also stable after chemical modification process to prepare the catalyst system. The TEM images of the catalyst showed the existence of palladium nanoparticles immobilized in the structure of the catalyst, while no reducing agent was used. It seems that the NHC groups and imidazolium moieties in the structure of the MOF can reduce Pd (II) to Pd (0) species. This modified MOF substrate can also prevent aggregation of Pd nanoparticles, resulting in high stability of them in organic transformation. The Pd−NHC−MIL-101(Cr) catalyst system could be simply extracted from the reaction mixture, providing an efficient synthetic method for the synthesis of biaryls derivatives using the aforementioned coupling reaction. The Pd−NHC−MIL-101(Cr) catalyst could be recycled in this organic reaction with almost consistent catalytic efficiency. 相似文献
83.
A novel triazine-phosphanimine polymeric organic support (TPA) was synthesized successfully by a controllable one-pot method using melamine (1,3,5-triazine-2,4,6-triamine) and trichlorophosphane (PCl3). The TPA substrate is a material incorporating P and N atoms which can coordinate with metals as a pincer ligand to stabilize them, providing an efficient heterogeneous support to prepare recyclable transition metal catalyst systems. In this study, TPA was used as support to immobilize iridium nanoparticles in the range of ~8 nm on its surface, resulting in the generation of a novel iridium nanocatalyst system (INP-TPA-POP). This catalyst system was characterized using different microscopic and spectroscopic techniques such as FT-IR, TEM, XPS, XRD, SEM, EDX, elemental analysis, ICP and BET analysis. The INP-TPA-POP nanocatalyst exhibited remarkable activity in reduction of aldehydes to alcohols using formic acids as reducing agent in ethanol as solvent. 相似文献
84.
Rasti Behnam Mazraedoost Sargol Panahi Hanieh Falahati Mojtaba Attar Farnoosh 《Molecular diversity》2019,23(2):263-273
Molecular Diversity - Nowadays, antibiotic resistance has turned into one of the most important worldwide health problems. Biological end point of critical enzymes induced by potent inhibitors is... 相似文献
85.
G. Solookinejad M. Panahi E. A. Sangachin S. H. Asadpour 《Journal of Experimental and Theoretical Physics》2016,122(6):957-959
We consider excitations that exist, in addition to phonons, in the ideal Bose gas at zero temperature. These excitations are vortex rings whose energy spectrum is similar to the roton one in liquid helium. 相似文献
86.
The use of starch‐modified magnetic Fe0 nanoparticles for naphthalene adsorption from water samples: Adsorption isotherm,kinetic and thermodynamic studies
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Maryam Malekzadeh Arezoo Nejaei Mohammad Mehdi Baneshi Esmaeel Panahi Kokhdan Hassan Bardania 《应用有机金属化学》2018,32(8)
This study was aimed at investigating the effectiveness of starch‐modified magnetic nanoparticles for the removal of naphthalene, which is a polycyclic aromatic hydrocarbon present in the majority of water sediments, from water resources. Magnetic Fe0 nanoparticles have recently been considered because of their high efficiency for contaminant removal. In the present study, Fe0 nanoparticles were synthesized using sulfate method and starch was used as a stabilizer. The size of the Fe0 nanoparticles was measured as approximately 45 nm using X‐ray diffraction and scanning electron microscopy analyses. The removal efficiency of naphthalene from water using the nanoparticles was evaluated based on various factors including the viscosity of naphthalene dissolved in water, and operation factors such as nanoparticle dosage, contact time, initial naphthalene concentration and pH in non‐continuous reactors were optimized. The results revealed that the starch‐modified nanoparticles have high efficiency for removal of dissolved naphthalene from aqueous solution. Under the optimum conditions, more than 99% of naphthalene at a pH of 5.0 with nanoparticle dosage of 0.05 g was removed from aqueous solution in 5 min. The equilibrium adsorption data were interpreted in terms of Langmuir, Freundlich and Temkin isotherm models and the goodness of fit was inspected using linear regression analysis. Our results indicated that the Langmuir model with maximum adsorption capacity was best fitted, suggesting monolayer adsorption. Moreover, it was found that the adsorption process followed the pseudo‐second‐order kinetic model. In addition, a thermodynamic study indicated that the adsorption process of naphthalene from aqueous solution by the starch‐modified nanoparticles was spontaneous and exothermic. 相似文献
87.
Nonlinear Dynamics - Models of neurons play an essential role in computational neuroscience. They provide a virtual laboratory to analyze the different regimes in the electrical activities of a... 相似文献
88.
Mohsen Nikoorazm Arash Ghorbani-Choghamarani Atefeh Panahi Bahman Tahmasbi Nourolah Noori 《Journal of the Iranian Chemical Society》2018,15(1):181-189
A Pd-Schiff-base grafted on functionalized mesoporous MCM-41 (Pd(0)-Schiff-base@MCM-41) was prepared using a post-grafting procedure and used as a highly efficient and reusable nanostructural catalyst for the carbon–carbon cross-coupling reactions of various aryl halides (including aryl iodide, bromide and chloride) with sodium tetraphenyl borate, phenylboronic acid and butyl acrylate. This catalyst exhibits interesting reactivity through Heck and Suzuki reactions. 相似文献
89.
Two‐phase and three‐phase liquid‐phase microextraction of hydrochlorothiazide and triamterene in urine samples
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Homayon Ahmad Panahi Maryam Ejlali Monireh Chabouk 《Biomedical chromatography : BMC》2016,30(7):1022-1028
This paper reports the applicability of two‐phase and three‐phase hollow fiber based liquid‐phase microextraction (HF‐LPME) for the extraction of hydrochlorothiazide (HYD) and triamterene (TRM) from human urine. The HYD in two‐phase HF‐LPME is extracted from 24 mL of the aqueous sample into an organic phase with microliter volume located inside the pores and lumen of a polypropylene hollow fiber as acceptor phase, but the TRM in three‐phase HF‐LPME is extracted from aqueous donor phase to organic phase and then back‐extracted to the aqueous acceptor phase, which can be directly injected into HPLC for analysis. Under optimized conditions preconcentration factors of HYD and TRM were obtained as 128 and 239, respectively. The calibration curves were linear (R2 ≥ 0.995) in the concentration range of 1.0–100 µg/L for HYD and 2.0–100 µg/L for TRM. The limits of detection for HYD and TRM were 0.5 µg/L. The intra‐day and inter‐day RSD based on four replicates were obtained as ≤5.8 and ≤9.3%, respectively. The methods were successfully applied for determining the concentration of the drugs in urine samples. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
90.
Allahvirdinesbat Maryam Fozi Mohaddeseh Safa Kazem D. Alyari Maryam Nakhostin Panahi Parvaneh Niaei Aligholi 《Research on Chemical Intermediates》2017,43(4):2653-2668
Research on Chemical Intermediates - An improved one-pot and ecofriendly approach to tri- and tetraaryl imidazoles through three- and four-component coupling reactions under neutral and... 相似文献