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排序方式: 共有647条查询结果,搜索用时 46 毫秒
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Saeed Bahadorikhalili Samira Ansari Haleh Hamedifar Leila Ma'mani Mohsen Babaei Rahim Eqra Mohammad Mahdavi 《应用有机金属化学》2019,33(4)
In this paper, a novel catalyst is introduced based on the immobilization of palladium on modified magnetic graphene oxide nanoparticles. The catalyst is characterized by several methods, including transmission electron microscopy, scanning electron microscopy, X‐ray fluorescence, vibrating‐sample magnetometer, Fourier transform‐infrared and dynamic light scattering (DLS) analysis. The activity of the catalyst was investigated in the synthesis of 4(3H)‐quinazolinones via Pd‐catalyzed carbonylation‐cyclization of N‐(2‐bromoaryl) benzimidamides by Mo (CO)6. The Mo (CO)6 is used as a carbon monoxide source for performing the reaction under mild conditions. The catalyst showed good reusability, and no change in activity was observed after 10 cycles of recovery. 相似文献
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Ouayl Chadli Qamrul Hasan Ansari Suliman Al-Homidan 《Journal of Optimization Theory and Applications》2017,172(3):726-758
The main goal of this paper is to introduce and study bilevel vector equilibrium problems. We first establish some existence results for solutions of vector equilibrium problems and mixed vector equilibrium problems. We study the existence of solutions of bilevel vector equilibrium problems by considering a vector Thikhonov-type regularization procedure. By using this regularization procedure and existence results for mixed vector equilibrium problems, we establish some existence results for solutions of bilevel vector equilibrium problems. By using the auxiliary principle, we propose an algorithm for finding the approximate solutions of bilevel vector equilibrium problems. The strong convergence of the proposed algorithm is also studied. 相似文献
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Nazish Parveen Mohammad Omaish Ansari Thi Hiep Han Moo Hwan Cho 《Journal of Solid State Electrochemistry》2017,21(1):57-68
This paper reports a simple methodology for the synthesis of a polyaniline/titanium oxide/graphene hybrid (Pani/TiO2/GN) using a simple methodology, and their application as a supercapacitor electrode material for energy storage. The Pani/TiO2/GN hybrid was prepared by a simple approach by simultaneous generation of Pani and TiO2 in situ from aniline and titanium iso-propoxide, respectively, in the presence of GN under ice bath conditions. The incorporation of GN improved the electrical conductivity of Pani and helped to decrease the charge transfer resistance, whereas TiO2 generation by an in situ method increased the surface area considerably and enhanced the capacitance of the Pani/TiO2/GN hybrid. TEM showed that Pani and TiO2 were well incorporated and coated on the GN successfully. The shift of the peaks in the FTIR spectrum and XRD pattern of the Pani/TiO2/GN hybrid compared to their pure counterparts suggested that TiO2 and Pani had been perfectly coated on the GN, and there was a strong interaction among Pani, GN, and TiO2 particles. The electrochemical performance of the as-prepared Pani/TiO2/GN hybrid electrode showed a high specific capacitance of 403.2 F g?1 at a current density of 2 A g?1 and excellent cycling stability for up to 1000 cycles. This suggested that the effective incorporation of GN and TiO2 into Pani and the high surface area could simultaneously increase the electrochemical capacitance and cyclic stability of the Pani/TiO2/GN hybrid, leading to superior electrochemical performance. 相似文献
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Structural Chemistry - Mononuclear and dinuclear iron complexes are found as key intermediates in many synthetic and biocatalytic reactions, since many of these species are transient and have high... 相似文献
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Novel 1,2,3,4‐Tetrahydroquinazolinones via Reaction of 2‐Amino‐N‐substituted Benzamides and Dimethyl Acetylenedicarboxylate 下载免费PDF全文
Semiramis Nahavandian Sadegh Allameh Mina Saeedi Shirin Ansari Mohammad Mahdavi Alireza Foroumadi Abbas Shafiee 《Helvetica chimica acta》2015,98(7):1028-1033
Reaction of 2‐amino‐N‐substituted benzamides and dimethyl acetylenedicarboxylate (DMAD) in the presence of 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in H2O at room temperature led to the formation of novel 1,2,3,4‐tetrahydroquinazolinones. 相似文献
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A numerical study of the onset of longitudinal transition between turbulent and laminar regimes during the evaporation of a water film is presented. These water film streams along a horizontal elliptical tube under the simultaneous effects of gravity, pressure gradients, caused by the vapor flow and curvature, and viscous forces. At the interface of water vapor, the shear stress is supposed to be negligible. Outside the boundary layer, the vapor phase velocity is obtained from potential flow. In the analysis Von Karmans turbulence model is used and the inertia and convection terms are retained. Transfers equations are discretised by using the implicit Keller method. The effects of an initial liquid flow rate per unit of length, Froude number, temperature difference between the wall and the liquid–vapor interface and ellipticity on the transition position have been evaluated. The transition criterion has been given in term of the critical film Reynolds number (Re)C. 相似文献
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A distributed fiber optic sensor is developed for condition monitoring of civil infrastructure sys-tems. The fiber optic sensor is especially useful in applications involving structures strengthened by fiberreinforced polymer (FRP) composites. The sensor principles are simple and therefore, practical for detec-tion of cracks, debonding and deformation measurements. Structural monitoring capability of the sensor 相似文献