排序方式: 共有181条查询结果,搜索用时 810 毫秒
151.
We report the synthesis of magnetically separable Fe3O4@Silica‐Threonine‐Pd0 magnetic nanoparticles with a core–shell structure. After synthesis of Fe3O4@Silica, threonine as an efficient stabilizer/ligand was bonded to the surface of Fe3O4@Silica. Then, palladium nanoparticles were generated on the threonine‐modified catalyst. The threonine stabilizer helps to generate palladium nanoparticles of small size (less than 4 nm) with high dispersity and uniformity. Magnetically separable Fe3O4@Silica‐Threonine‐Pd0 nanocatalyst was fully characterized using various techniques. This nanocatalyst efficiently catalysed the Heck cross‐coupling reaction of a variety of substrates in water medium as a green, safe and inexpensive solvent at 80°C. The Fe3O4@Silica‐Threonine‐Pd0 catalyst was used for at least eight successful consecutive runs with palladium leaching of only 0.05%. 相似文献
152.
Gholizadeh Khasevani Sepideh Gholami Mohammad Reza 《Research on Chemical Intermediates》2019,45(3):1341-1356
Research on Chemical Intermediates - In this study, we synthesized novel visible light photocatalyst MIL-88A/BiOI using depositing BiOI particles on the surface of a metal–organic framework... 相似文献
153.
Magnetically recoverable and environmentally friendly Cu‐based heterogeneous catalyst has been synthesized for the one‐pot conversion of aldehydes to their corresponding primary amides. The Fe3O4@SiO2 nanocomposites were prepared by synthesis of Fe3O4 magnetic nanoparticles (MNPs) which was then coated with a silica shell via Stöber method. Bi‐functional cysteine amino acid was covalently bonded onto the siliceous shell of nanocatalyst. The CuII ions were then loaded onto the modified surface of nanocatalyst. Finally, uniformly dispersed copper nanoparticles were achieved by reduction of CuII ions with NaBH4. Amidation reaction of aryl halides with electron‐withdrawing or electron‐donating groups and hydroxylamine hydrochloride catalyzed with Fe3O4@SiO2@Cysteine‐copper (FSC‐Cu) MNPs in aqueous condition gave an excellent yield of products. The FSC‐Cu MNPs could be easily isolated from the reaction mixture with an external magnet and reused at least 8 times without significant loss in activity. 相似文献
154.
This paper investigates the nonlinear boundary value problem resulting from the exact reduction of the Navier-Stokes equations for unsteady magnetohydrodynamic boundary layer flow over the stretching/shrinking permeable sheet submerged in a moving fluid. To solve this equation, a numerical method is proposed based on a Laguerre functions with reproducing kernel Hilbert space method. Using the operational matrices of derivative, we reduced the problem to a set of algebraic equations. We also compare this work with some other numerical results and present a solution that proves to be highly accurate. 相似文献
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Sulfonic acid groups were grafted onto three different types of synthesized magnetic nanoparticles, namely Fe3O4, Fe3O4@SiO2, and Fe3O4@MCM‐48. The sulfonic acid‐functionalized nanoparticles were evalu... 相似文献
158.
Gholivand Khodayar Mohammadpanah Fahimeh Yaghoubi Rouhollah Rahimzadeh Dashtaki Maryam Pooyan Mahsa Rahmani Hamidreza Roshanian Zahra Sharifi Mahboobeh EbrahimiValmoozi Ali Asghar Roohzadeh Roohollah 《Molecular diversity》2022,26(3):1519-1530
Molecular Diversity - In an attempt to obtain the modified and novel insecticides with low human toxicity, a series of novel mono-, bis-, and tetraphosphonic acid derivatives were designed and... 相似文献
159.
Bakherad Mohammad Keivanloo Ali Gholizadeh Mostafa Doosti Rahele Javanmardi Mohaddese 《Research on Chemical Intermediates》2017,43(2):1013-1029
Research on Chemical Intermediates - A facile, eco-friendly, and highly efficient one-pot four-component protocol is demonstrated for the synthesis of the pyrano[2,3-c]pyrazole and... 相似文献
160.
Soraia Meghdadi Mahsa Kiani Farzaneh Fadaei Tirani Maryam Bagheri Kurt Job Schenk 《Journal of Coordination Chemistry》2017,70(14):2409-2424
Two carboxamide ligands, H2bqbenzo {3,4-bis(2-quinolinecarboxamido)benzophenone} and H2bqb {N,N′-bis[(2-quinolinecarboxamide)-1,2-benzene]}, have been prepared using tetrabutylammonium bromide as an environmentally benign reaction medium. Two new Pd(II) complexes, [PdII(bqbenzo)] (1) and [PdII(bqb)] (2), have been synthesized, characterized, and their structures determined by single crystal X-ray diffraction. The di-anionic ligands, bqbenzo2? and bqb2?, are coordinated via two Namide atoms and the nitrogens of the two quinoline rings, with Pd?Namide < Pd–Nquinoline bond lengths. The geometry around palladium(II) in both complexes is distorted square planar. The electrochemical behaviors of the ligands and their Pd(II) complexes have been investigated by cyclic voltammetry in DMF. An irreversible PdII/I reduction is observed at ?1.06 V for 1 and at ?1.177 V for 2, indicating the influence of the R substituent on the central phenyl ring of carboxamide ligands on the PdII/I reduction potential. The ligands and palladium complexes were also screened for in vitro antibacterial activity. The Pd(II) complexes show strong biological activity against S.typhi and E.coli as Gram ?ve and B.cereus and S.aureus as Gram +ve bacteria comparable to the antibiotic penicillin. The antibacterial results also reveal that coordination of Pd(II) significantly improves the activity. 相似文献