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排序方式: 共有291条查询结果,搜索用时 46 毫秒
241.
Yu Xie Ye Yuan Bibimaryam Mousavi Yuan Cai Cheng Kai Yin Lu Mehman Yusubov Francis Verpoort 《应用有机金属化学》2015,29(9):573-579
Olefin metathesis is a transition metal‐mediated transformation that rearranges the carbon atoms of the carbon–carbon double bond of olefins. This reaction has become one of the most important and powerful reactions. Therefore development of new, well‐defined, highly active and selective catalysts is very desirable and a valuable goal. This mini‐review mainly introduces the development of ruthenium catalysts in olefin metathesis highlighting oxygen‐chelated indenylidene ruthenium catalysts. Applying an alkoxyl group on the indenylidene ligand fragment can generate the Ru ? O chelating bond. Additionally, various modifications of the ligand as well as the catalytic activity for ring‐closing metathesis reaction and selectivity of cross metathesis reaction are overviewed. Finally, the perspectives on the development of new catalysts are summarized. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
242.
Hamze Mousavi 《Journal of magnetism and magnetic materials》2011,323(11):1537-1540
We study the effects of the electron-phonon interaction on the temperature dependence of the orbital magnetic susceptibility of monolayer graphene. We use the linear response theory and Green's function formalism within the Holstein Hamiltonian model. The results show that the effects of the electron-phonon interaction on the susceptibility of graphene sheet have different behaviors in two temperature regions. In the low temperature region, susceptibility increases when the electron-phonon coupling strength increases. On the other hand, the susceptibility reduces with increasing the electron-phonon coupling strength in the high temperature region. 相似文献
243.
Mir Rasul Mousavi Malek Taher Maghsoodlou Sayyed Mostafa Habibi-Khorassani 《Molecular diversity》2014,18(4):821-828
A series of 2-oxo-N,4,6-triarylcyclohex-3-enecarboxamides were synthesized by condensing acetophenone and aromatic aldehydes with acetoacetanilide in ethanol in the presence of 2-hydroxyethylammonium acetate (2-HEAA) as a basic ionic liquid at ambient conditions. This process is simple, efficient and environmentally benign and proceeds in high yield, short reaction times and there is no need for column chromatography purification. 相似文献
244.
Mojtaba Bagherzadeh Narges-alsadat Mousavi Mojtaba Amini Sanjeev Gautam Jitendra Pal Singh Keun Hwa Chae 《中国化学快报》2017,28(5):1125-1130
Cu2O nanocubes, octahedra, spheres and truncated rhombic dodecahedral were prepared and their structural, morphological, and electronic properties were investigated by X-ray diffraction analysis, X-ray absorption near edge structure, scanning electron microscope and transmission electron microscope and X-ray absorption near edge structure. Cu2O nanocrystals were successfully employed to catalyze the 1,3-dipolar cycloaddition reaction for the synthesis of 1,4-disubstituted triazoles. Cu2O nanocubes and octahedral showed the superior catalytic performance in the cycloaddition reaction. These results reveal that crystal-plane engineering of oxide catalysts is a useful strategy for developing efficient catalysts for organic reaction. 相似文献
245.
Mehdi Bakavoli Mohammad Rahimizadeh Ali Shiri Marzieh Akbarzadeh Seyed‐Hadi Mousavi Zahra Tayarani‐Najaran Hoda Atapour‐Mashhad Mohsen Nikpour 《Journal of heterocyclic chemistry》2011,48(1):183-187
Starting from pyrimido[4,5‐e][1,3,4]oxadiazines ( 3a , 3b , 3c ) , a synthetic pathway to [1,2,4]triazolo[4′,3′:1,2]pyrimido[4,5‐e][1,3,4]oxadiazines ( 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i ) is described. The reaction of pyrimido[4,5‐e][1,3,4]oxadiazines ( 3a , 3b , 3c ) with hydrazine hydrate afforded the corresponding hydrazino derivatives ( 4a , 4b , 4c ) . Further treatment of these compounds with different orthoesters in acetic acid gave the corresponding [1,2,4]triazolo[4′,3′:1,2]pyrimido[4,5‐e][1,3,4]oxadiazines ( 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i ) . Compound ( 3a ) and ( 5b ) , as examples, were tested on different cancer cell lines including HeLa, MCF‐7, and HepG2. Malignant cells were cultured in DMEM medium and incubated with different concentrations of the titled compounds. Cell viability was quantitated by MTT assay. J. Heterocyclic Chem., (2010). 相似文献
246.
Seyedeh Zeinab Mousavi‐Sani Jahan Bakhsh Raoof Reza Ojani Ezat Hamidi‐Asl 《中国化学会会志》2013,60(6):650-656
In this paper, nano‐gold modified carbon paste electrode (NGMCPE) was employed to develop an electrochemical DNA hybridization biosensor. The proposed sensor was made up by immobilization of 15‐mer single stranded oligonucleotide probe for detection of target DNA. Hybridization detection relies on the alternation in guanine oxidation signal following hybridization of the probe with complementary genomic DNA. The guanine oxidation was monitored using differential pulse voltammetry (DPV). Different factors such as activation potential, activation time and probe immobilization conditions were optimized. The selectivity of the sensor was investigated by non‐complementary oligonucleotides. Diagnostic performance of the biosensor was described and the detection limit was found 1.9 × 10?13 M at the NGMCPE surface. All of the investigations were performed in both CPE and NGMCPE and finally their results were compared. 相似文献
247.
Jian‐An Huang Mansoureh Z. Mousavi Giorgia Giovannini Yingqi Zhao Aliaksandr Hubarevich Miguel A. Soler Walter Rocchia Denis Garoli Francesco De Angelis 《Angewandte Chemie (International ed. in English)》2020,59(28):11423-11431
The SERS‐based detection of protein sequences with single‐residue sensitivity suffers from signal dominance of aromatic amino acid residues and backbones, impeding detection of non‐aromatic amino acid residues. Herein, we trap a gold nanoparticle in a plasmonic nanohole to generate a single SERS hot spot for single‐molecule detection of 2 similar polypeptides (vasopressin and oxytocin) and 10 distinct amino acids that constitute the 2 polypeptides. Significantly, both aromatic and non‐aromatic amino acids are detected and discriminated at the single‐molecule level either at individual amino acid molecules or within the polypeptide chains. Correlated with molecular dynamics simulations, our results suggest that the signal dominance due to large spatial occupancy of aromatic rings of the polypeptide sidechains on gold surfaces can be overcome by the high localization of the single hot spot. The superior spectral and spatial discriminative power of our approach can be applied to single‐protein analysis, fingerprinting, and sequencing. 相似文献
248.
Synthesis and morphological investigation of pulsed current formed nano-structured lead dioxide 总被引:1,自引:0,他引:1
Shahram Ghasemi Hassan Karami Mir Fazlollah Mousavi Mojtaba Shamsipur 《Electrochemistry communications》2005,7(12):1257-1264
An electro-forming method was used for the preparation of nano-structured lead dioxide on lead substrate in 4.8 M H2SO4. A two electrode system composed of two similarly prepared lead electrodes was employed. A constant current was applied between two electrodes for a short time, followed by a relaxation period. A dark oxidation film of suitable stability and homogeneity was formed on the anode electrode. Different parameters including pulse height, pulse time (ton) and relaxation time (toff) were optimized. A change in morphology of lead dioxide from globular to nanofibriliar was observed when the pulse time and relaxation time varied from 0.01 to 10 and 0.1 to 5 s, respectively, at a pulse height of 25 mA cm−2. A variation in pulse height caused a variation in diameter and length of nanofibers formed at a pulsed time of 0.1 s and relaxation time of 5 s. The scanning electron microscopy (SEM) showed that lead dioxide particles obtained under these conditions have nanofibriliar morphology with an average diameter in the range between 20 and 50 nm and length of 500–1000 nm. 相似文献
249.
G. Heidari S. M. Mousavi Khoie M. Yousefi M. Ghasemifard 《Russian Journal of Electrochemistry》2016,52(5):470-476
Simultaneous solution of two kinetic models of electrodeposition of copper in sulfate solution is studied in this paper. Bulk concentration of species involved in the numerical solution was calculated using MATLAB software. COMSOL Multiphysics software was used for the numerical solution of copper electrodeposition. Numerical results were evaluated using experimental data obtained by linear sweep voltammetry technique. The experimental data was almost fitted using COMSOL optimization physic module. It was found that kinetic parameters of Cu2+ (k1Cu), Cu1+ (k2Cu), and CuCitH (k1CuCitH) and diffusion coefficient and charge transfer coefficient of Cu2+ (\({D_{C{u^{2 + }}}}\), αCu1), Cu1+ (αCu2) and CuCitH (DCuCitH, αCuCitH) affect the fitting of the experimental data with the computed ones. The variables such as concentration profiles and optimum kinetic parameters that cannot be experimentally measured were achieved by analysis of the model. The parameters, that not affect the fitting, were recognized and kept constant when using the optimization. 相似文献
250.
Heshmatollah Alinezhad Mahmood Tajbakhsh Mahboobeh Zare Mahbooeh Mousavi 《Chemical Papers》2016,70(8):1126-1130
A one-pot three-component Biginelli-like reaction of enaminones, aldehydes with urea/thiourea in the presence of 2-pyrrolidonium bisulphate as an acidic ionic liquid catalyst for the preparation of 6-unsubstituted dihydropyrimidinones is described. The excellent yield, short reaction time, simple procedure and avoidance of the use of organic solvents are some advantages of this method. 相似文献