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151.
Farhad Shirini Mohammad A. Zolfigol Abdol-Reza Abri 《中国化学快报》2008,19(1):51-54
Fe(NO3)3-9H2O/Fe(HSO4)3 was used as an efficient reagent system for the oxidation of alcohols to their corresponding carbonyl compounds. All reactions were performed in the absence of solvent in good to high yields. Under the same reaction conditions, thiols and sulfides were also converted to their corresponding disulfides and sulfoxides, respectively. 2007 Farhad Shirini. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 相似文献
152.
A mild, efficient and fast method for direct oxidation of trimethylsilyl, tetrahydropyranyl and methoxymethyl ethers to their corresponding carbonyl compounds using trinitratocerium(Ⅳ) bromate (TNCB) supported on NaHSO4.H2O under solvent-free conditions is reported. 相似文献
153.
This study aims to investigate the recovery of L-lactic acid from fermentation broth by an emulsion liquid membrane (ELM), made up of sunflower oil as the diluent, Sorbitan monooleate (Span 80) as the surfactant, Aliquat 336 as the carrier, and sodium hydroxide (NaOH) solution as the internal aqueous phase. Particularly, the ELM process was properly set up, through the identification of the optimal ELM operating parameters on the final extraction efficiency of L-lactic acid, including Span 80 concentration, NaOH concentration, Aliquat 336 concentration, stirring speed, phase ratio, and treatment ratio. The obtained results showed that the extraction efficiency of L-lactic acid reached up to 99% under the following optimal conditions: 10 minutes after contact time, 4% w/w Span 80, 3% w/w Aliquat 336, 0.1?N solution of NaOH, stirring speed of 300?rpm, phase ratio 1, and treatment ratio 0.25. A stable system without considerable emulsion swelling and breakage was monitored using a dynamic light scattering (DLS) apparatus for the selected optimal ELM operating parameters. 相似文献
154.
Masoumeh Abedini Farhad Shirini Maryam Mousapour Omid Goli Jolodar 《Research on Chemical Intermediates》2016,42(7):6221-6229
A simple and efficient procedure for the synthesis of benzo[4,5]imidazo[1,2-α]pyrimidine and 2-amino-4-substituted-1,4-dihydrobenzo[4,5]imidazolo[1,2-α]pyrimidine-3-carbonitrile derivatives using poly(vinylpyrrolidonium) perchlorate {[PVPH]ClO4} as a newly reported, modified polymeric catalyst is reported. Some of the advantages of this novel synthetic method are: easy preparation of the catalyst, simple and easy work-up procedure, short reaction times, high to excellent yields of the products and reusability of the catalyst. 相似文献
155.
Pourdasht Sepideh Mousapour Maryam Shirini Farhad Tajik Hassan 《Research on Chemical Intermediates》2022,48(10):4403-4418
Research on Chemical Intermediates - In this work, 1,1-(butane-1,4-diyl)bis(tropinium)chloride is prepared, identified and used for the promotion of the synthesis of polyhydroquinoline and... 相似文献
156.
157.
Farhad HSSEINOV 《数学学报(英文版)》2013,29(6):1185-1198
The paper studies a relaxation of the basic multidimensional variational problem, when the class of admissible functions is endowed with the Lipschitz convergence introduced by Morrey. It is shown that in this setup, the integral of a variational problem must satisfy a classical growth condition, unlike the case of uniform convergence. The relaxations constructed here imply the existence of a Lipschitz convergent minimizing sequence. Based on this observation, the paper also shows that the Lavrentiev phenomenon does not occur for a class of nonconvex problems. 相似文献
158.
159.
Mahnaz Enayati-Jazi Mehran Solati-Hashjin Ali Nemati Farhad Bakhshi 《Superlattices and Microstructures》2012
Hydroxyapatite/titania nanocomposites were successfully synthesized by in situ precipitation of precursor matters from hydroxyapatite and titania at 70 °C with different hydroxyapatite/titania ratios. X-ray diffraction, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller surface, scanning and transmission electron microscopes were employed to characterize the prepared nanocomposite powders. X-ray diffraction results indicated that hydroxyapatite and anatase (TiO2) were the major crystalline phases. By increasing the amount of titania nano-particles, Fourier transform infrared spectroscopy revealed that (PO4)3− bands at 567, 1033 cm−1 decreased. Brunauer–Emmett–Teller surface results also showed a reduction in surface areas of nanocomposites. Transmission electron microscope observations revealed that the aspect ratio of hydroxyapatite/TiO2 nanocrystals increased by increasing TiO2 proportion in nanocomposites. The observed nanorod crystals tended to thin, elongated and plate-like in shape. 相似文献
160.
Zeynizadeh Behzad Mousavi Hossein Sepehraddin Farhad 《Research on Chemical Intermediates》2020,46(7):3361-3382
Research on Chemical Intermediates - In this paper, a new application of the Fe3O4@APTMS@Cp2ZrClx(x = 0, 1, 2) MNPs as a robust and highly efficient Pd-free catalytic system in the environmentally... 相似文献