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81.
A. Nozad Golikand M. Ghannadi Maragheh L. Irannejad M. Asgari 《Russian Journal of Electrochemistry》2006,42(2):167-172
Electrocatalytic oxidation of methanol on a glassy carbon disc electrode modified with Ni(II)-1-(2-pyridylazo)-2-naphthol
(Ni-PAN) complex and conditioned by potential recycling in a limited range (between 100–600 mV) in 0.1 M NaOH solution, abbreviated
as NiPANME, is studied by cyclic voltammetry in alkaline medium. The results are compared with those obtained for a NiO modified
glassy-carbon electrode, NiOME, prepared in similar conditions. The findings show that the NiPAN film behaves as an efficient
electrocatalyst for the oxidation of methanol in alkaline medium via Ni(III) species with the cross-exchange reaction occurring
throughout the layer at a low concentration of methanol and for a thin film of modifier. Effects of the scan rate and methanol
concentration on the methanol oxidation are investigated. The cyclic voltammetry and amperometry methods are used to investigate
the methanol electrooxidation at the modified electrode.
Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 2, pp. 196–202.
The text was submitted by the authors in English. 相似文献
82.
A one-pot, four-component condensation of an aryl aldehyde, an aryl ketone, acetyl chloride and acetonitrile in the presence of silica sulfuric acid as an active, inexpensive, recoverable and recyclable catalyst is disclosed for the synthesis of β-acetamido ketones. 相似文献
83.
In this work, using density functional theory, the kinetic effects of the substitution of a t‐butyl group and\or the incorporation of an oxygen atom, and both, at the aziridine ring moiety were investigated for N‐inversion in N‐phenylaziridine. Then, for N‐inversion in 3‐t‐butyl‐N‐phenyloxaziridine, the kinetic Hammett substituent effects were studied using the different para‐substituted groups on the N‐phenyl ring moiety. The natural bond orbital (NBO) study was the last case in this work. The calculations were performed in the gas phase and solution (in carbon tetrachloride and dichloromethane). The incorporation of an oxygen atom in the aziridine ring strongly weakens the N‐inversion process. In addition, while both t‐butyl substituent and solvent slightly reinforce the N‐inversion of N‐phenyloxaziridine, in N‐phenylaziridine, they decrease the N‐inversion rate to some extent. In both phases, more pronounced in solution and especially in dichloromethane, and in agreement with the NBO results, the electron‐withdrawing groups on para position of the N‐phenyl ring strongly increase the rate of N‐inversion of 3‐t‐butyl‐N‐phenyloxaziridine molecule. 相似文献
84.
Maithani Rajesh Kumar Anil Gholamali Zadeh Peyman Safaei Mohammad Reza Gholamalizadeh Ehsan 《Journal of Thermal Analysis and Calorimetry》2020,139(2):1195-1212
Journal of Thermal Analysis and Calorimetry - A study was conducted to enhance the thermo-hydraulic performance of a rectangular solar air passage with integrated spherical-shaped turbulence... 相似文献
85.
The exterior degree of a pair of finite groups (G, N), which is a generalization of the exterior degree of finite groups, is the probability for two elements (g, n) in (G, N) such that g ? n = 1. In the present paper, we state some relations between this concept and the relative commutatively degree, capability and the Schur multiplier of a pair of groups. 相似文献
86.
Alcohols and Phenols are protected efficiently with dihydropyran(DHP) in the presence of catalytic amounts of zirconium tetrachloride in dichloromethane. Deprotection of THP-ethers is also afforded in a methanolic solution at room temperature. 相似文献
87.
Mohammad S. Asgari Behnam Tahmasebi Somayeh Mojtabavi Mohammad A. Faramarzi Rahmatollah Rahimi Parviz R. Ranjbar Mahmood Biglar Bagher Larijani Hossein Rastegar Maryam Mohammadi-Khanaposhtani Mohammad Mahdavi 《Journal of heterocyclic chemistry》2020,57(12):4348-4357
A new series of acridine-9-carboxamide-1,2,3-triazole derivatives 7a-m were designed, synthesized, and evaluated as novel α-glucosidase inhibitors. Acridine-9-carboxamide-1,2,3-triazole scaffold has been designed by combination of effective moieties from potent α-glucosidase inhibitors. Most of the synthesized compounds were more potent than standard inhibitor acarbose. Among the title compounds, the most potent compounds were compounds 7j , 7k , and 7a with IC50 values of 120.2 ± 1.0, 151.1 ± 1.4, and 157.6 ± 1.6 μM, respectively (IC50 value of acarbose = 750.0 ± 10.0 μM). Docking study of the most potent compounds demonstrated that these compounds formed stable complexes with α-glucosidase active site. Anti-α-amylase assay of compounds 7j , 7k , and 7a was performed and no activity was observed. in vitro cytotoxicity assay of the latter compounds revealed that these compounds were not cytotoxic toward human normal (HDF) and cancer (MCF-7) cell lines. ADME and toxicity prediction of compounds 7j , 7k , and 7a were also performed. 相似文献
88.
89.
A series of graft copolymers were synthesized based on ethylene‐co‐m,p‐methylstyrene (EMS) (backbone copolymer), ethylene‐1‐hexene‐m,p‐methylstyrene (EHMS) (backbone terpolymer), and polyethylene glycol monomethyl ethers (PEGM) (grafts) in this study. The PEGMs with molecular weights of 750 and 2000 were used. The chemical composition of the graft copolymers was analyzed by NMR and DSC measurements. The graft copolymers exhibited a phase‐separated morphology with the backbone and the methoxy polyethylene glycol (MPEG) grafts forming separate crystalline phases. The MPEG phase had a melting temperature lower than the corresponding MPEG homopolymer, as determined by DSC. The melting point of the crystalline phase formed by the EMS and EHMS main chains was lower than that of pure polymer backbone. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
90.
Ali A. Asgari Amir H. Abbassi Jafar Khodagholizadeh 《The European Physical Journal C - Particles and Fields》2014,74(6):1-11
Recent studies have shown that searches in the mono-photon and missing energy final state can be used to discover dark matter candidates at the ILC. While an excess in this final state over the Standard Model background would indicate the existence of a dark sector, no detailed information about the internal structure of this sector can be inferred. Here, we demonstrate how just a few observables can discriminate between various realisations of dark sectors, including e.g. the spin of mediators. 相似文献