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排序方式: 共有293条查询结果,搜索用时 15 毫秒
1.
Nasirizadeh Navid Dehghani Mohammad Yazdanshenas Mohammad E. 《Journal of Sol-Gel Science and Technology》2015,73(1):14-21
Journal of Sol-Gel Science and Technology - In this paper, a simple method is presented for making a conductive and hydrophobic cotton fabric using a multi-walled carbon nanotube (MWCNT). The... 相似文献
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Summary Thin layers of stannic arsenate have been used to study the chromatographic behaviour of 57 metal ions in different mixed solvents. Au3+, Hg2+, UO
2
2+
, Be2+ and Al3+ and others can be easily separated from numerous metal ions. Fast quaternary, ternary and binary separations have been also achieved. Important separations are discussed. The effect of pH, duration of heating of ionexchanger plates and layer thickness on the Rf values has been studied and discussed. It is shown that Lederer's equation is also obeyed by thin layers of stannic arsenate, if instead of concentration of Na+ ion its activity is taken into consideration. 相似文献
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Electrochemical oxidation of 2,3‐dihydroxypyridine in aqueous phosphate buffer solution at a glassy carbon electrode has been studied using cyclic voltammetry and controlled potential coulometry. The results indicate that oxidation of 2,3‐dihydroxypyridine on glassy carbon electrode shows an irreversible feature in aqueous solution. This data indicates that the electrochemically generated pyridindione is unstable and via an oxidative conversion pathway converts to a novel highly oxygenated heterocyclic compound. By means of the obtained electrochemical data, an efficient, one‐pot method for the synthesis of this heterocyclic compound based on the oxidative cyclization of 2,3‐dihydroxypyridine under green conditions, and in a good yield and purity is described. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
6.
Hamid Reza Shaterian Asghar Hosseinian Majid Ghashang Fahimeh Khorami Neda Karimpoor 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2333-2338
An environmentally friendly procedure for the preparation of dihydropyrimidinone derivatives or their sulfur analogues under thermal solvent-free conditions in the presence of aluminium hydrogen sulfate [Al(HSO4)3] and alumina sulfuric acid (Al2O3-SO3H) as heterogeneous catalysts was developed. 相似文献
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The electrochemical oxidation of 1,4-dihydroxyanthraquinone has been studied in the presence of acetylacetone and benzoylacetone as nucleophiles in a mixture of ethanol/water by means of cyclic voltammetry as a diagnostic technique.The results indicate the participation of electrochemically produced anthraquinone in the Michael addition reaction with acetylacetone and benzoylacetone to form the corresponding new anthraquinone derivatives.On the basis of the EC mechanism,the observed homogeneous rate constants(kobs)of the reaction of anthraquinone with acetylacetone and benzoylacetone were estimated by comparing the experimental cyclic voltammograms with the digitally simulated results. 相似文献
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Soraia Meghdadi Mehdi Amirnasr Maryam Bagheri Fatemeh Ahmadi Najafabadi Kurt Mereiter Kurt Joß Schenk Fahimeh Ziaee 《Journal of the Iranian Chemical Society》2014,11(4):985-991
Nickel(II) and copper(II) complexes of two unsymmetrical tetradentate Schiff base ligands [Ni(Me-salabza)] (1), [Cu(Me-salabza)] (2) and [Ni(salabza)] (3), {H2salabza = N,N′-bis[(salicylidene)-2-aminobenzylamine] and H2Me-salabza = N,N′-bis[(methylsalicylidene)-2-aminobenzylamine]}, have been synthesized and characterized by elemental analysis and spectroscopic methods. The crystal structures of 2 and 3 complexes have been determined by single crystal X-ray diffraction. Both copper(II) and nickel(II) ions adopt a distorted square planar geometry in [Cu(Me-salabza)] and [Ni(salabza)] complexes. The cyclic voltammetric studies of these complexes in dichloromethane indicate the electronic effects of the methyl groups on redox potential. 相似文献
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Davood Nematollahi Saied Saeed Hosseiny Davarani Pari Mirahmadpour Fahimeh Varmaghani 《中国化学快报》2014,25(4):593-595
The electrochemical synthesis of some new sulfonamide derivatives was carried out via the electrochemical oxidation of 2,3-dihydrophthalazine-l,4-dione (1) in the presence of arylsulfinic acids (2a and 2b) as nucleophiles. The results show that, the electrogenerated phthalazine-l,4-dione (lox) participates in a Michael type addition reaction with 2a or 2b and via an EC mechanism to produce the corresponding sulfonamide derivatives. This method provides a one-pot procedure for the synthesis of new sulfonamide derivatives of potential biological significance in good yields without using toxic reagents at a carbon electrode in an environmentally friendly manner. 相似文献
10.
Aydin Berenjian Raja Mahanama Andrea Talbot Hubert Regtop John Kavanagh Fariba Dehghani 《Applied biochemistry and biotechnology》2014,172(3):1347-1357
A nutritional food rich in menaquinone-7 has a potential in preventing osteoporosis and cardiovascular diseases. The static fermentation of Bacillus subtilis natto is widely regarded as an optimum process for menaquinone-7 production. The major issues for the bulk production of menaquinone-7 are the low fermentation yield, biofilm formation and the use of organic solvents for the vitamin extraction. In this study, we demonstrate that the dynamic fermentation involving high stirring and aeration rates enhances the yield of fermentation process significantly compared to static system. The menaquinone-7 concentration of 226 mg/L was produced at 1,000 rpm, 5 vvm, 40 °C after 5 days of fermentation. This concentration is 70-fold higher than commercially available food products such as natto. Additionally, it was found that more than 80 % of menaquinone-7 was recovered in situ in the vegetable oil that was gradually added to the system as an anti-foaming agent. The intensification process developed in this study has a capacity to produce an oil rich in menaquinone-7 in one step and eliminate the use of organic solvents for recovery of this compound. This oil can, therefore, be used for the preparation of broad range of supplementary and dietary food products rich in menaquinone-7 to reduce the risk of osteoporotic fractures and cardiovascular diseases. 相似文献