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61.
62.
Saba Hemmati Mohammad Yousefi Mirmehdi Hashemi Salehi Mahdis Amiri Malak Hekmati 《应用有机金属化学》2020,34(8):e5653
This paper develops a green method for in situ decorated of palladium nanoparticles over Fe3O4 nanoparticles, by utilizing Strawberry fruit extract and ultrasound irradiations, with no use of any toxic reducing agent. The structure's characterization is represented via diverse analytical methods such as FT-IR, FE-SEM, TEM, WDX, ICP, EDS and XXPS. Catalytic efficiency of magnetic Fe3O4@Strawberry/Pd nanocatalyst is investigated in production of different biphenyls with good turnover frequencies (TOF) and turnover numbers (TON) through Suzuki coupling reactions. Furthermore, the catalyst could be recovered and reused 7 runs without considerable palladium leaching or alteration in its performance. 相似文献
63.
64.
A new class of 2-arylamino-dihydroxyindenopyrroles were prepared by the one-pot multicomponent reaction of ninhydrin, N-methyl-1-(methylthio)-2-nitroethenamine and aromatic amines in EtOH at room temperature. The advantages of this procedure are short reaction times, good to high yields, easy separation of products and good functional group tolerance. 相似文献
65.
A method for one-step synthesis of ultrafine agarose-coated superparamagnetic iron oxide nanoparticles (AC-SPIONs) was developed. The method is facile and fast and requires no organic solvent or surfactant. The average particle size of the prepared AC-SPIONs was only 20–40 nm with a narrow size distribution and with large saturation magnetization at room temperature. The obtained ultrafine nanogel particles were characterized by scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, transmission electron microscopy and vibrating sample magnetometer techniques. The AC-SPIONs were epoxy-activated by epichlorohydrin and aminated by ammonium hydroxide. The amination of the particles was investigated by the Kaiser test. The adsorption of two model compounds (gallic acid and ellagic acid) on the functionalized nanoparticles and their releases from them were investigated spectrophotometrically in three different pH values under biological conditions. The functionalized AC-SPIONs displayed good adsorption and in vitro drug release in a phosphate-buffered saline (pH 7.4). The ultrafine AC-SPIONs can be potentially used in magnetic solid-phase extraction, drug delivery, protein purification and enzyme immobilization methods. 相似文献
66.
Under solvent free conditions between 40-50 °C, BF3.SiO2, a mild solid acid catalyst, is applied to regio-chemo and stereoselective Claisen-Schmidt condensation. The procedure is very simple and the products are isolated with an easy workup in good to excellent yields. 相似文献
67.
Khalili B Jajarmi P Eftekhari-Sis B Hashemi MM 《The Journal of organic chemistry》2008,73(6):2090-2095
New 2-alkyl-5-aryl-(1H)-pyrrole-4-ol derivatives were synthesized via three-component reaction of beta-dicarbonyl compounds with arylglyoxals in the presence of ammonium acetate in water at room temperature. 相似文献
68.
Primary and secondary benzylic alcohols were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant, H2O2 catalyzed by montmorillonite K-10 supported cobalt(Ⅱ) chloride. 相似文献
69.
Let R be a semiprime left Goldie ring with
a monomorphism and
an α-derivation, then
is semiprimitive left Goldie ring. 相似文献
70.
Seyfollah Toroghi Ahmad Khayat Jafari Ala Hashemi Golpayegani 《Optics & Laser Technology》2009,41(6):800-803
In this paper, the dependence of the absorbed power on the temperature in an end-pumped CW quasi-three-level Yb:YAG thin disk laser is calculated. Here, we have used the temperature-dependent form of the Boltzmann occupation factors, absorption cross-section and thermal conductivity of the Yb:YAG crystal. A Monte Carlo ray tracing code and a 2D finite element analysis (FEA) with the ANSYS package have been used to calculate the absorbed power and the temperature distribution inside the Yb:YAG thin disk laser, respectively. According to the model, the temperature-dependent absorbed power turns out to be 18% less than the temperature-independent absorbed power in the top center of the Yb:YAG thin disk laser for used parameters. 相似文献