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51.
Maasoumeh Jafarpour Abdolreza Rezaeifard Reza Haddad Somayeh Gazkar 《Transition Metal Chemistry》2013,38(1):31-36
A zirconium(IV) complex of a bidentate Schiff base (ZrL2Cl2) has been synthesized by the reaction of (z)-N-benzylidene-2-hydroxypropane-1-amine (HL) and ZrCl4. Spectroscopic data and elemental analyses are consistent with a monomeric complex with a ligand:Zr ratio of 2:1. The catalytic activity of ZrL2Cl2 has been investigated for the efficient synthesis of a wide variety of quinoxaline derivatives under mild conditions. The employment of ethanol as an environmentally benign solvent in this high yield method, along with high turnover numbers and reusability of the catalyst providing ready scalability, makes it appropriate for practical applications. 相似文献
52.
Seyyed Abdolreza Fazeli Seyyed Mohammad Hosseini HashemiHootan Zirakzadeh Mehdi Ashjaee 《Superlattices and Microstructures》2012
In this paper, heat transfer characteristics of a miniature heat sink cooled by SiO2–water nanofluids were investigated both experimentally and numerically. The heat sink was fabricated from aluminum and insulated by plexiglass cover plates. The heat sink consisted of an array of 4 mm diameter circular channels with a length of 40 mm. Tests were performed while inserting a 180 W/cm2 heat flux to the bottom of heat sink and Reynolds numbers ranged from 400 to 2000. The three-dimensional heat transfer characteristics of the heat sink were analyzed numerically by solving conjugate heat transfer problem of thermally and hydrodynamically developing fluid flow. Experimental results showed that dispersing SiO2 nanoparticles in water significantly increased the overall heat transfer coefficient while thermal resistance of heat sink was decreased up to 10%. Numerical results revealed that channel diameter, as well as heat sink height and number of channels in a heat sink have significant effects on the maximum temperature of heat sink. Finally, an artificial neural network (ANN) was used to simulate the heat sink performance based on these parameters. It was found that the results of ANN are in excellent agreement with the mathematical simulation and cover a wider range for evaluation of heat sink performance. 相似文献