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61.
Naser Foroughifar Akbar Mobinikhaledi Hassan Moghanian Reza Mozafari Hamid R. M. Esfahani 《合成通讯》2013,43(18):2663-2673
A one-pot, multicomponent reaction of aldehydes, dimedone, and β-naphthols is described for the preparation of 12-aryl- or 12-alkyl-8,9,10,12-tetrahydrobenzo[α]xanthen-11-one derivatives using ammonium chloride as a mild, inexpensive, and environmentally benign catalyst under solvent-free conditions. Different types of aldehyde and β-naphthol derivatives are used in the reaction, and in all cases the products were synthesized successfully.
62.
There is a high overvoltage in the oxidation of methanol in fuel cells, and so modified electrodes are used to decrease it. A modified electrode that used Ni(Ⅱ) loaded analcime zeolite to catalyze the electrooxidation of methanol in alkaline solution was proposed. Analcime zeolite was synthesized by hydrothermal synthesis, and Ni(Ⅱ) ions were incorporated into the analcime structure, which was then mixed with carbon paste to prepare modified electrode. The electrocatalytic oxidation of methanol on the surface of the modified electrode in alkaline solution was investigated by cyclic voltammetry and chronoamperometry. The effects of the scan rate of the potential, concentration of methanol, and amount of zeolite were investigated. The rate constant for the catalytic reaction of methanol was 6×103 cm3 mol-1 s-1 from measurements using chronoamperometry. The proposed electrode significantly improved the electron transfer rate and decreased the overpotential for methanol oxidation. 相似文献
63.
Oxidation of hydrogen cyanide with ozone on the singlet potential energy surface is carried out using the MP2 and CCSD(T)//MP2 theoretical approaches in connection with the 6-311++G(d,p) basis set. In this reaction, energy barrier of transition states are low, so the reaction of HCN with ozone can occur easily at atmospheric condition. With variety of pre-reactive complex, five types of products are obtained at the MP2 method which four types of them have enough thermodynamic stability at the standard condition. CO2 + HNO are final adducts in a process that is computed to be exothermic by ?132.605 kcal/mol in standard enthalpy and spontaneous by ?144.166 kcal/mol in Gibbs free energy of reaction. In kinetic viewpoint, the production of OCN + HO2 adducts path with one low level transition state is the most favored path. 相似文献
64.
Akbar Mobinikhaledi Naser Foroughifar Mohammad Ali Bodaghi Fard Hassan Moghanian Sattar Ebrahimi Mehdi Kalhor 《合成通讯》2013,43(7):1166-1174
An efficient Hantzsch four-component condensation reaction for the synthesis of polyhydroquinoline derivatives was reported under two conditions: solvent-free conventional heating and energy-saving microwave irradiation. The process is simple and environmentally benign, and the use of a heterogeneous and reusable catalyst, high yields, and short reaction times are the key features of this protocol. 相似文献
65.
Bahram Hemmateenejad Mojtaba Shamsipur Naser Jalili–Jahani 《Photochemistry and photobiology》2016,92(1):61-68
Nanospheres of Ag‐coated Fe3O4 were successfully synthesized and characterized. Photocatalytic properties of Fe3O4@Ag composites have been investigated using steady‐state studies and laser pulse excitations. Accumulation of the electrons in the Ag shell was detected from the shift in the surface plasmon band from 430 to 405 nm, which was discharged when an electron acceptor such as O2, Thionine (TH) or C60 was introduced into the system. Charge equilibration with redox couple such as C60●–/C60 indicated the ability of these core–shell structures to carry out photocatalytic reduction reactions. As well, outer Ag layer could boost charge separation in magnetic core through dual effects of Schottky junction and localized surface plasmonic resonance (LSPR)‐powered band gap breaking effect under sunlight irradiation; resulted in higher photocatalytic degradation of diphenylamine (DPA). The maximum photocatalytic degradation rate was achieved at optimum amount of Ag‐NP loading to products. Adsorption studies confirmed that degradation of DPA dominantly occurred in solution. Moderately renewability of the nanocatalysts under sunlight was due to oxidation and dissolution of the outer Ag layer. 相似文献
66.
Ahmad Shaabani Naser Safari Samad Shoghpour Ali Hossein Rezayan 《Monatshefte für Chemie / Chemical Monthly》2008,139(6):613-615
A very simple and mild reaction is described for the aerobic oxidative coupling of thiols to disulfides by silica-supported
cobalt(II) tetrasulfophthalocyanine as the catalyst in non-aqueous media under neutral conditions at room temperature. The
catalyst can be reused for the oxidative coupling of several thiols without any significant loss of catalytic activity.
Correspondence: Ahmad Shaabani, Department of Chemistry, Shahid Beheshti University, P.O. Box 19396, 4716 Tehran, Iran. 相似文献
67.
Moheb Amir Mahani Ahmad Naseri Karimvand Naser Naserifar 《Journal of separation science》2023,46(19):2300257
Point-of-care diagnostics requires a smart separation of particles and/or cells. In this work, the multiorifice fluid fractionation as a passive method and dielectrophoresis-based actuator as an active tool are combined to offer a new device for size-based particle separation. The main objective of the combination of these two well-established techniques is to improve the performance of the multiorifice fluid fractionation by taking advantage of dielectrophoresis-based actuator for separating particles. Initially, by using numerical simulations, the effect of using dielectrophoresis-based actuator in multiorifice fluid fractionation on the separation of particles was investigated, and the size of the device was optimized by 25% compared to a device without dielectrophoresis-based actuator. Also, adding dielectrophoresis-based actuator to multiorifice fluid fractionation can extend the range of flow rates needed for separation. In the absence of dielectrophoresis-based actuator, the separation took place only when the flow rate is 100 μL/min, in the presence of dielectrophoresis-based actuator (20 Vp-p), the separation happened in flow rates ranging from 70 to 120 μL/min. 相似文献
68.
Alireza Mashayekhi Seyed Mahmoud Hosseini Morteza Hassanpour Amiri Naser Namdar Zeinab Sanaee 《Journal of nanoparticle research》2016,18(6):154
Nitrogen doping of vertically aligned carbon nanotubes (VACNTs) using plasma-enhanced chemical vapour deposition has been investigated to improve the supercapacitance performance of CNTs. Incorporating electrochemical measurements on the open-ended nitrogen-doped CNTs, showed the achievement of 6 times improvement in the capacitance value. For nitrogen-doped CNTs on silicon substrate, specific capacitance of 60 F g?1 was obtained in 0.5 M KCl solution, with capacity retention ratio above 90 % after cycled at 0.1 A g?1 for 5000 cycles. Using this sample, a symmetric supercapacitance was fabricated which showed the power density of 37.5 kW kg?1. The facile fabrication approach and its excellent capacitance improvement, propose it as an efficient technique for enhancing the supercapacitance performance of the carbon-based electrodes. 相似文献
69.
采用一种简易的方法制备了新型Ni(OH)2-X/CPE电极,并将其用于电催化氧化甲醛反应.采用扫描电镜和能量散射谱对所制Ni(OH)2-X/CPE电极进行了表征,并运用循环伏安法、电化学阻抗谱和计时电流法考察了该电极的电化学性能.结果表明,该Ni(OH)2-X/CPE电极对甲醛氧化表现出高电催化活性,这归功于X具有纳米孔结构和大的比表面积.电子传递系数和催化反应速率常数分别为0.7和6.1×104 cm3/(mol·s).该电极对甲醛氧化具有高而稳定的电催化活性,且制备重复性高,有望应用于燃料电池中. 相似文献
70.
Rostampour Malihe Aboudzadeh Mohammadreza Sadeghi Mahdi Hamidi Saeid Alirezapour Behroz Soltani Naser Aslani Gholamreza 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1759-1766
Excitation functions and theoretical yields via charge particle induced reactions were evaluated using EMPIRE-3.2.2 and ALICE/ASH codes and the obtained results have been discussed and compared with the available reported experimental data. It has been verified that natCu(p,n)65Zn reaction is the optimum 65Zn production route. The 65Zn was produced using natCu(p,xn) 65Zn reaction in the energy range of 16.8 → 12.2 MeV with the thick target yield of 0.15 ± 0.005 MBq/μA h. The 65Zn radionuclide was purified by anion exchange chromatography.
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