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821.
Hossein Soltani Hadi Beitollahi Abdol-Hamid Hatefi-Mehrjardi Somayeh Tajik Masoud Torkzadeh Mahani 《Ionics》2014,20(10):1481-1488
A carbon paste electrode modified with benzoylferrocene (BF) and carbon nanotubes (CNTs) have been applied to the electrocatalytic oxidation of homocysteine which reduced the overpotential by about 165 mV with an obvious increase in the current response. The transfer coefficient (α) for the electrocatalytic oxidation of homocysteine and diffusion coefficient of this substance under the experimental conditions were also investigated. In a phosphate buffer solution (PBS) of pH 7.0, the oxidation current increased linearly with two concentration intervals of homocysteine; one is 0.1 to 10.0 μM, and the other is 10.0 to 80.0 μM. The detection limit (3σ) obtained by square wave voltammetry (SWV) was 50.0 nM. The proposed method was successfully applied to the determination of homocysteine in real samples. 相似文献
822.
Masoud Bezi Javan Samaneh Ebrahimi 《Applied Physics A: Materials Science & Processing》2014,114(2):529-536
We studied the structural, electronic, and magnetic properties of C59Ir, C58Ir2, and C69Ir heterofullerenes by employing density functional theory and the generalized gradient approximation. There are six distinct isomers of C58Ir2 with high probability to form stable structures. The most stable structure of the C69Ir heterofullerene was investigated by comparing the iridium binding energies at the different atomic sites on the D5h C70 cage. There is a strong hybridization between the atomic orbitals of the iridium and those of the carbon atoms, leading to the spin quenching of the iridium atoms in the most stable C58Ir2 heterofullerene. 相似文献
823.
Moslem Mansour Lakouraj Bahareh Aghajani Masoud Mokhtary 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2393-2401
The facile immobilization of hydroperoxide on the cross-linked poly(vinylpyrrolidone) is described by treatment of a poly(vinylpyrrolidone)-Vilsmeier adduct with (35%) hydrogen peroxide. The in situ–generated poly(vinyl pyrrolidone)-supported hydroperoxide reagent showed very good performance in chemoselective oxidation of aldehydes to carboxylic acids as well as sulfides to sulfoxides. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
824.
Narges Sharifi Mahdi Ardjmand Morteza Ghorbanzadeh Ahangari Masoud Darvish Ganji 《Structural chemistry》2013,24(5):1473-1483
The characteristics of lithium adsorption on Si-decorated graphene are investigated using first-principles density functional theory calculations. It is found that the Si atom is strongly adsorbed at the bridge site of the C–C bond with binding energy of about ?26.75 kcal/mol. We show that Si decorating turns Si:graphene complex into an electron-deficient system and significantly enhances the Li-storage capacity on the graphene. The obtained results indicate that up to eight Li-ions being adsorbed onto the Si-decorated graphene can form the stable complex. It is found, interestingly, that two Si atoms coated onto double-side of the graphene can strongly adsorb sixteen Li-ions. The analyses of electronic structures show a strong interaction between Li-ions and Si-decorated graphene leading to a high exothermicity. The stability of the sixteen Li-ions adsorbed on the Si:graphene system was evaluated with ab initio molecular dynamics simulation which have been carried out at room temperature. Our first-principles results are relevant to identify the potential applications of Si-decorated graphene as superior media for Li-ions storage. 相似文献
825.
Mehdi Ghandi Shahab Sheibani Masoud Sadeghzadeh Fariba Johari Daha Maciej Kubicki 《Journal of the Iranian Chemical Society》2013,10(6):1057-1065
An efficient catalyst-free and diastereoselective synthesis of novel dihydropyrano[2,3-d]pyrimidine and dihydropyrano[3,2-c]chromen-annulated benzosultams is described. A number of (E)-N-(2-formylphenyl)-N-methyl-2-phenylethenesulfonamides were synthesized and underwent a one-pot domino Knoevenagel hetero-Diels–Alder reaction, respectively, with N,N-dimethylbarbituric acid and 4-hydroxycoumarin in water, giving the desired products, in moderate to excellent yields. 相似文献
826.
The molecular and electronic structure of the CuCl2-complexes with monoethanolamine (MEA) and triethanolamine (TEA), and their dynamical properties in solid and in DMF solutions were discussed on the basis of EPR measurements. Measurements indicate a dimeric structure of CuCl2-MEA complexes with very weak Cu-Cu coupling. Intradimer superexchange interaction is temperature dependent and decreases with temperature. In CuCl2-TEA monomeric complexes exist with a significant vibronic effect which is due to a change of dZ2 admixture to the d x2-y2 ground state when temperature is changed. 相似文献