排序方式: 共有77条查询结果,搜索用时 562 毫秒
61.
Mohammad Nikpassand Manouchehr Mamaghani Farhad Shirini Khalil Tabatabaeian 《Ultrasonics sonochemistry》2010,17(2):301-305
Fused polycyclic 4-aryl-3-methyl-4,7-dihydro-1H-pyrazolo[3,4-b]pyridines were obtained in a three-component regioselective reaction of 5-amino-3-methyl-1H-pyrazole, 2H-indene-1,3-dione and arylaldehydes in ethanol under ultrasound irradiation. This rapid method produced the products in short reaction times (4–5 min) and excellent yields (88–97%). 相似文献
62.
Manouchehr Zaker 《Journal of Graph Theory》2008,58(2):110-122
In this article we first give an upper bound for the chromatic number of a graph in terms of its degrees. This bound generalizes and modifies the bound given in 11 . Next, we obtain an upper bound of the order of magnitude for the coloring number of a graph with small K2,t (as subgraph), where n is the order of the graph. Finally, we give some bounds for chromatic number in terms of girth and book size. These bounds improve the best known bound, in terms of order and girth, for the chromatic number of a graph when its girth is an even integer. © 2008 Wiley Periodicals, Inc. J Graph Theory 58:110–122, 2008 相似文献
63.
Analcime shell-nickel ferrite core microspheres were decorated with Pd and Pt nanoparticles with the aid of an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6). The samples thus prepared were characterized using X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), nitrogen adsorption-desorption isotherms, transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) methods. The XRD patterns confirmed the growth of a zeolitic layer on the surface of the magnetic cores. The thermogravimetric analysis (TGA) curve clearly indicated the thermal decomposition of the loaded IL, which confirmed the presence of BMIM-PF6 in the structures. In addition, EDX analysis indicated that the samples contained 2.5 mass % of noble metal. The metallic species can be adsorbed on the modified surface and/or penetrate into the zeolitic channels in the structures. The results indicate that the X-IL/An/S/NF (X = Pt or Pd) metallic nanoparticles supported core-shell catalysts-samples were able to catalyse the selective oxidation of cyclohexene to 2-cyclohexene-1-ol under the induced conditions. The catalysts continued to be active after recycling up to 5 times. Eventually, a suitable mechanism was proposed for the selective oxidation of cyclohexene over the catalysts. 相似文献
64.
65.
We give a characterization of bicomplex-holomorphic anti-Hermitian manifolds by using pure metric connection 相似文献
66.
Khalil Tabatabaeian Hannaneh Heidari Manouchehr Mamaghani Nosrat O. Mahmoodi 《应用有机金属化学》2012,26(2):56-61
A number of ruthenium complexes were prepared and their catalytic activities in three‐component one‐pot condensation of aldehydes, malononitrile and 4‐hydroxycoumarin or dimedone was considered to afford dihydropyrano[3,2‐c]chromenes and tetrahydrobenzo[b]pyran derivatives under optimum reaction conditions. We found that a catalytic amount of RuBr2(PPh3)4 efficiently promotes the reaction in a short time (3–15 min) and with high yield (75–88%). Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
67.
Novel 4,5-diphenyl-1H-imidazol-1-yl-1H-1,2,4-triazole derivatives were synthesized using a facile and highly efficient, one-pot, four-component procedure in the presence of KHSO4 as an acidic catalyst under ultrasonic irradiations in short reaction times (10–25 min) and good to excellent yields (70–96%). The synthesized compounds were screened for their antibacterial activities against Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and Gram-positive (Bacillus subtilis, Micrococcus luteus) bacteria, and their antioxidant activity was also evaluated. Some of the products showed potential antibacterial and high antioxidant activities. 相似文献
68.
Pegah Farokhian Manouchehr Mamaghani Nosrat Ollah Mahmoodi Khalil Tabatabaeian 《Journal of the Iranian Chemical Society》2018,15(1):11-16
An efficient and practical protocol was developed for the synthesis of novel pyrano[2,3-c]pyrazoles and bis-pyrano[2,3-c]pyrazoles by one-pot four-component reaction of arylaldehyde, ethyl acetoacetate, hydrazine hydrate and dimethyl malonate using SO3H-functionalized ionic liquid [DMBSI]HSO4 as a potential green catalyst under solvent-free condition. The method presented is mild, environmentally friendly, inexpensive and functionality tolerant and produces the desired pyranopyrazoles in short reaction times (17–24 min) and excellent yields (85–95%). In addition, the catalyst can be reused at least ten times without almost any change in its catalytic activity. 相似文献
69.
Manouchehr Mamaghani Khalil TabatabaeianAli Ghanadzadeh Fatemeh Habibi 《Tetrahedron letters》2003,44(25):4775-4777
Pig's liver esterase (PLE) was used efficiently in phosphate buffer for the separation of stereoisomeric mixtures of cis/trans-ethyl arylglycidates, produced via Darzen's condensation reactions. 相似文献
70.
Leila Zare Nosratollah Mahmoodi Asieh Yahyazadeh Manouchehr Mamaghani Khalil Tabatabaeian 《Journal of heterocyclic chemistry》2011,48(4):864-867
The first one‐pot synthesis of pyridazinones and phthalazinones from arenes, cyclic anhydrides, and ArNHNH2 in the presence of efficient recyclable heterogeneous catalyst, HY‐zeolite, in high yield and short reaction time is reported. J. Heterocyclic Chem., (2011). 相似文献