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排序方式: 共有250条查询结果,搜索用时 15 毫秒
31.
Roya Akbarzadeh Tayebeh Amanpour Peiman Mirzaei Ayoob Bazgir 《Helvetica chimica acta》2011,94(8):1527-1532
Pyrano‐pyrido‐quinoxaline derivatives were synthesized in good yields by a three‐component reaction of isocyanides, dialkyl acetylenedicarboxylates, and pyrido[1,2‐a]quinoxaline‐triones in DMF at 100°. 相似文献
32.
Mehdi Adib MohammadHosein Sayahi SomayehAali Koloogani Peiman Mirzaei 《Helvetica chimica acta》2006,89(2):299-303
The reactive 1 : 1 zwitterionic intermediates generated in situ from the reaction between a series of isocyanides and diaroylacetylenes were trapped by pyridine carbaldehydes to yield highly functionalized 5‐pyridylfuran‐2‐amines in good yields (82–93%). 相似文献
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34.
Davoud Mirzaei 《Journal of Computational and Applied Mathematics》2010,233(10):2737-2754
During the past few years, the idea of using meshless methods for numerical solution of partial differential equations (PDEs) has received much attention throughout the scientific community, and remarkable progress has been achieved on meshless methods. The meshless local Petrov-Galerkin (MLPG) method is one of the “truly meshless” methods since it does not require any background integration cells. The integrations are carried out locally over small sub-domains of regular shapes, such as circles or squares in two dimensions and spheres or cubes in three dimensions. In this paper the MLPG method for numerically solving the non-linear two-dimensional sine-Gordon (SG) equation is developed. A time-stepping method is employed to deal with the time derivative and a simple predictor-corrector scheme is performed to eliminate the non-linearity. A brief discussion is outlined for numerical integrations in the proposed algorithm. Some examples involving line and ring solitons are demonstrated and the conservation of energy in undamped SG equation is investigated. The final numerical results confirm the ability of proposed method to deal with the unsteady non-linear problems in large domains. 相似文献
35.
Lingling Zhang Haiyang Cui Zhi Zou Tayebeh Mirzaei Garakani Catalina Novoa‐Henriquez Bahareh Jooyeh Ulrich Schwaneberg 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(14):4610-4613
Escherichia coli's copper efflux oxidase (CueO) has rarely been employed in the cathodic compartment of enzymatic biofuel cells (EBFCs) due to its low redox potential (0.36 V vs. Ag/AgCl, pH 5.5) towards O2 reduction. Herein, directed evolution of CueO towards a more positive onset potential was performed in an electrochemical screening system. An improved CueO variant (D439T/L502K) was obtained with a significantly increased onset potential (0.54 V), comparable to that of high‐redox‐potential fungal laccases. Upon coupling with an anodic compartment, the EBFC exhibited an open‐circuit voltage (Voc) of 0.56 V. Directed enzyme evolution by tailoring enzymes to application conditions in EBFCs has been validated and might, in combination with molecular understanding, enable future breakthroughs in EBFC performance 相似文献
36.
Mohammadreza Mohammadi Nilash Fahimeh Mirzaei Ali Reza Fakhari 《Journal of separation science》2019,42(9):1786-1793
A new sample preparation method based on SBA‐15 assisted electromembrane extraction coupled with corona discharge ion mobility spectrometer was developed for the determination of Thiabendazole as a model basic pesticide in fruit juice samples. The addition of SBA‐15 in the supported liquid membrane in electromembrane extraction system not only can lead to enhancement of the effective surface area, but also introducing the negatively charged silanol groups into supported liquid membrane might improve migration of positively charged analytes toward the supported liquid membrane and finally into the acceptor solution. To investigate the effect of the presence of SBA‐15 in the supported liquid membrane on the extraction efficiency, a comparative study was carried out between the conventional electromembrane extraction and SBA‐15/electromembrane extraction methods. Under the optimized conditions, SBA‐15/electromembrane extraction method showed higher extraction efficiencies in comparison with conventional electromembrane extraction method. SBA‐15/electromembrane extraction method exhibited a low limit of detection (0.9 ng/mL), high preconcentration factor (167) and high recovery (83%). Finally, the applicability of SBA‐15/electromembrane extraction method was studied by the extraction and determination of Thiabendazole as a model basic pesticide in fruit juice samples. 相似文献
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38.
S. Shahraki A. Heidari H. R. Mirzaei M. Saeidifar N. Ahmadinasab H. Mansouri-Torshizi 《Journal of the Iranian Chemical Society》2018,15(3):697-709
A novel 1,1-cyclobutanedicarboxylato-8-hydroxyquinolinatopalladate(II), Na[Pd(8-QO)(cbdca)] (8-QO = 8-hydroxyquinoline and cbdca = 1,1-cyclobutanedicarboxylate) has been designed and synthesized. The structure of the complex has been characterized by elemental analysis, molar conductance, FT-IR, UV–Vis, 13C NMR, 1H NMR spectroscopy. The cytotoxic activities of the complex have been tested against human foreskin fibroblast normal cell line, HFFF2 and two human breast cancer cell lines, T47D and MCF-7 by MTT assay techniques. The binding properties of the antitumor complex with calf thymus DNA (ctDNA) have been investigated under physiological condition in Tris–HCl buffer solution at pH 7.0 by absorption spectroscopy, fluorescence titration spectra, EB displacement and gel chromatography studies. All these results demonstrate that the water soluble complex can cooperatively bind to ctDNA at low concentrations through a static quenching procedure. Thermodynamic parameters were calculated according to Van’t Hoff equation which indicated that hydrogen bond and van der Waals force play predominant roles in the binding process. Finally, the results of molecular docking calculations clarify the binding mode which is in good accordance with experimental results. 相似文献
39.
Javad Azizian Ali A. Mohammadi Ilyar Bidar Peiman Mirzaei 《Monatshefte für Chemie / Chemical Monthly》2008,139(7):805-808
A simple, efficient, and practical procedure for the Pechmann condensation using KAl(SO4)2 · 12H2O (alum) as a non-toxic, reusable, inexpensive, and easily available catalyst is described under solvent-free condition at
65°C. These improved reaction conditions allow the preparation of a wide variety of some new substituted coumarins in high
yields (86–96%) and purity under mild reaction conditions. Compared to the classical Pechmann condensation, this new method consistently has the advantage of high yields.
Correspondence: Ali A. Mohammadi, Department of Chemistry, Shahid Beheshti University, P.O. Box 19839-4716, Tehran, Iran. 相似文献
40.
Issa Yavari Nargess Hosseini Loghman Moradi Anvar Mirzaei 《Tetrahedron letters》2008,49(27):4239-4241
A mild, convenient, and practical one-pot procedure for direct synthesis of N,N′-dialkyl-N″-dialkylaminocarbothioyl thioureas is described via three-component reaction of cyclic secondary amines, CS2, and N,N′-dialkyl carbodiimides in water at room temperature. 相似文献