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71.
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
72.
Protein capturing on polymeric substrate of microfluidic devices is a key factor for the fabrication of immunoassay with high sensitivity. In this work, simple and versatile technique of electrospinning was used to produce electrospun nanofibrous membranes (e.NFMs) with high surface area as a substrate for microfluidic‐based immunoassay to increase sensitivity. It was found that the simultaneous use of e.NFM and 1‐Ethylethyl‐3‐(3‐dimethylaminopropyl)‐carbodiimide/N‐Hydroxysuccinimide hydroxysuccinimide as coupling agent has synergic effect on antigen immobilization onto the microchannels. It was found that the oxygen plasma technique for the creation of oxygen containing functional group like carboxyl and hydroxyl causes extreme leakage of solution through the microchannels. Thus, due to capillary effect, it is impossible to use hydrophilic substrate to modify microchannels. In order to compensate this problem, it is propose to utilize other type of polymer for the fabrication of nanofiber to answer this important question that if it is possible to enhance the sensitivity of immunoassay just by changing the polymer type? For this purpose, four different polymers, namely, polycaprolactone, poly lactic‐co‐glycolic acid, poly L‐lactic acid, and polyethersolfone were used as the based material for e.NFM fabrication. Results showed that compared with plain poly (dimethylsiloxane) surface of microchannels, poly lactic‐co‐glycolic acidand poly L‐lactic acid, which inherently contain end‐group of carboxyl in their chemical structure, can improve the protein immobilization, which leads to immunoassay signal enhancement through 1‐ethyl‐3‐(3‐dimethylaminopropyl)‐carbodiimide/N‐hydroxysuccinimide coupling chemistry, significantly. 相似文献
73.
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
74.
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
75.
We give a characterization of bicomplex-holomorphic anti-Hermitian manifolds by using pure metric connection 相似文献
76.
Manouchehr Zaker 《Discrete Mathematics》2011,(14):1365
In this paper we discuss the existence of lower bounds for the chromatic number of graphs in terms of the average degree or the coloring number of graphs. We obtain a lower bound for the chromatic number of K1,t-free graphs in terms of the maximum degree and show that the bound is tight. For any tree T, we obtain a lower bound for the chromatic number of any K2,t-free and T-free graph in terms of its average degree. This answers affirmatively a modified version of Problem 4.3 in [T.R. Jensen, B. Toft, Graph Coloring Problems, Wiley, New York, 1995]. More generally, we discuss δ-bounded families of graphs and then we obtain a necessary and sufficient condition for a family of graphs to be a δ-bounded family in terms of its induced bipartite Turán number. Our last bound is in terms of forbidden induced even cycles in graphs; it extends a result in [S.E. Markossian, G.S. Gasparian, B.A. Reed, β-perfect graphs, J. Combin. Theory Ser. B 67 (1996) 1–11]. 相似文献