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31.
An extremely efficient heterogeneous protocol is reported for the one-pot, three-component synthesis of a series of dihydropyrimidinones (DHPMs) in the presence of ZnO nanoparticles in water as a green solvent. The ZnO nanoparticles exhibited excellent catalytic activity and the proposed methodology is capable of providing the desired products in good yields (65–94%) within short reaction times. After the reaction course, ZnO nanoparticles can be recycled and reused without any apparent loss of activity, which makes this ecofriendly process cost-effective. 相似文献
32.
Firouz Matloubi Moghaddam Zohreh Mirjafary Hamdollah Saeidian Behzad Koushki Foroushani Saghar Nourian 《合成通讯》2013,43(13):1941-1949
The synthesis of bicyclo[3.3.1]nonane systems is reported. The synthesis is based on the tandem 1,3-dinucleophilic addition of 4-hydroxy-2-quinolinone to quinolinium salts. 相似文献
33.
Rahman Hosseinzadeh Mahmood Tajbakhsh Maryam Mohadjerani Parizad Rezaei Mohammad Alikarami 《合成通讯》2013,43(17):3023-3031
An efficient synthesis of diaryl ethers by the copper-catalyzed arylation of phenols with a variety of aryl iodide susing KF/Al2O3 as a suitable base and CuI and 1,3 diphenyl-1,3 propandione as the catalyst is described. 相似文献
34.
NaBH4 in the presence of charcoal (0.4–0.8 g) reduces varieties of nitroarenes to their corresponding amines. Reduction reactions were carried out in a mixture of H2O‐THF (1:0.5 mL) at 50–60°C with high to excellent yields of products. 相似文献
35.
Farnaz Farbod Behzad Pourabbas Mehdi Sharif 《Journal of Polymer Science.Polymer Physics》2013,51(6):441-451
Breath figure formation was carried out directly on the surface of poly(methylmethacrylate) using a mixture of a good solvent, tetrahydrofuran, and a nonsolvent, water. Direct breath figure formation was coined for this method and a mechanism was proposed to describe the figure formation by the method based on hypothesizes available for the normal breath figure formation. The proposed mechanism is such that the sonication effect, immersion time, and water content on characteristics of the obtained figures can be explained. The figured surface was then made superhydrophobic with a water contact angle of 175° using in situ growing of perfluoro modified silica nanoparticles inside the figure cell by one-pot method. The spherical modified silica nanoparticles were detected being trapped by figure features providing a mechanical entrapment of the low-surface energy nanoparticles. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 相似文献
36.
Behzad Koozegar Kaleji Navid Hosseinabadi Akira Fujishima 《Journal of Sol-Gel Science and Technology》2013,65(2):195-203
In this study, preparation of Sn and Nb co-doped TiO2 dip-coated thin films on glazed porcelain substrates via sol–gel process have been investigated. The effects of co-doping content on the structural, optical, and photo-catalytic properties of applied thin films have been studied by X-ray diffraction (XRD), field emission SEM (FE-SEM), high resolution transmission electron microscopy (HR-TEM), and UV–Vis absorption spectroscopy. Surface chemical state of thin films was examined by atomic X-ray photoelectron spectroscopy (XPS). XRD results suggest that adding impurities has a great effect on the crystallinity and particle size of TiO2. Titania Rutile phase formation in thin film was promoted by Sn4+ addition but was inhibited by Nb5+ doping. The prepared co-doped TiO2 photo-catalyst films showed optical absorption edge in the visible light area and exhibited excellent photo-catalytic ability for degradation of methylene blue (MB) solution under solar irradiation. Comparison with undoped and Sn or Nb-doped TiO2, codoped TiO2 shows an obviously higher catalytic activity under solar irradiation. 相似文献
37.
H. Derakhshankhah A. A. Saboury A. Divsalar H. Mansouri-Torshizi I. Bamery D. Ajloo A. A. Moosavi-Movahedi R. Hosseinzadeh M. R. Ganjali H. Ilkhani H. R. Khavasi 《Journal of the Iranian Chemical Society》2014,11(5):1381-1390
A di-copper(II) complex of the formula [(dien)Cu(μ-1,6-DAH)Cu(dien)(NO3)2](NO3)2, where μ-1,6-DAH = 1,6-diaminohexane, has been synthesized and characterized by X-ray crystallography, X-ray powder diffraction, thermal gravimetric (TG) and differential thermal analyses, cyclic voltammetry, infrared, ultraviolet visible spectroscopies and elemental analysis methods. It was crystallized in a monoclinic system, space group P21/n, with a = 8.0297(8) Å, b = 12.4937(14) Å, c = 15.3786(15) Å, β = 102.739(8) Å and z = 2. Each copper(II) has a square-based pyramidal coordination geometry with four N atoms building the basal plane (three from dien and one from μ-1,6-DAH). TGA study of the complex revealed the compound to be stable up to 245 °C. Electrochemical behavior of complex and enzyme-like catalytic activity of this complex, as a potential functional model for the active site of tyrosinase, was studied extensively. Kinetic studies show that the complex has the maximum enzymatic activity at pH 8, temperature of 40 °C and ionic strength of 50 mM. 相似文献
38.
Hosseinzadeh Kh. Asadi A. Mogharrebi A. R. Ermia Azari M. Ganji D. D. 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1081-1095
Journal of Thermal Analysis and Calorimetry - In this study, flow of a mixture of water and ethylene glycol (50–50%) with hybrid nanoparticles (MWCNT–Ag) over a vertical stretching... 相似文献
39.
40.
Polyurethane (PU) have been prepared by using polyether polyol (jagropol oil) and 1,6-hexamethylene diisocyanate (HMDI) as a cross-linker. The organically modified montmorillonite clay (o-MMT) is well dispersed into urethane matrix by in-situ polymerization method. A series of PU/o-MMT nanocomposites have been prepared by varying amounts viz., 1, 3, 5 and 6 wt % of nanoclay. The mechanical properties such as tensile strength, percentage elongation at break and tensile modulus of the composites were experimentally determined. The swelling behavior of the composites has been studied in different organic solvents. It was noticed that the swelling data of the composites significantly depends on the solubility parameters of the solvents. Microcrystalline parameters such as, lattice strain (g in %), average number of unit cells (〈N〉) in direction perpendicular to Bragg plane, surface weighted crystal size (D s) and interplanar distance (d hkl ), were calculated from X-ray patterns. These parameters were computed using Exponential asymmetric column length distribution functions. Morphological features of cryofractured PU/o-MMT composites were also analyzed using scanning electron microscopy (SEM). 相似文献