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981.
Abdulaziz M. Al-Jalal Mohammad Aslam Khan 《Plasma Chemistry and Plasma Processing》2010,30(1):173-182
We demonstrate that low-pressure glow discharges in He–O2 gas mixture are effective in removing carbonaceous surface layers from coked catalysts. These discharges contain a number
of reactive species including O, O3, and O2*, and all these could contribute in the decoking process. However, an evolving understanding is that the O atoms in the discharge
have a predominant role in this. A working hypothesis is that the O atoms react with the coke to form CO, CO2 and other carbon complexes. Online measurements using emission spectra from O, H, and CO in the discharges are compared for
the cases of He–O2 and Ar–O2 gas mixtures. Under the reported experimental conditions the estimated reactivity of the He–O2 discharges is considerably higher compared with discharges in the Ar–O2 gas mixture. Raman spectroscopy is used to confirm the removal of the coke from the surface of Pt/Alumina catalyst. 相似文献
982.
Only 10 mol% of l-Proline in ethanol proved to be a very efficient catalyst for the one-pot synthesis of a wide variety of highly substituted tetrahydrobenzo[c]acridin-8(7H)-ones at room temperature. The key advantages of this process are high yields, cost effectiveness of the catalyst, easy work-up and the products can be directly recrystallized from hot ethanol. 相似文献
983.
A mild and efficient method for the synthesis of 1H-chromeno[2,3-d]pyrimidine-5-carboxamide derivatives via a one-pot, three-component reaction of an isocyanide, barbituric acid, and a salicylaldehyde in the presence of acetic acid in ethanol/water mixture at 75 °C is reported. This high atom economy reaction led to the construction of one benzopyran ring, and one amide group in a single synthetic step. 相似文献
984.
The Cu(I)-catalyzed cascade coupling/cyclization reaction of N-tosylhydrazones with 3-butyn-1-ol has been explored. This new strategy represents a simple platform for the synthesis of tetrahydrofurans in moderate to good yields. 相似文献
985.
Hashemzadeh Alireza Amini Mostafa M. Najafi Ezzatollah Khavasi Hamid Reza 《Research on Chemical Intermediates》2017,43(10):5741-5753
Research on Chemical Intermediates - To systematically examine the effects of the length and number of aromatic rings in carboxylic acid ligands on the structure and properties of lead(II)... 相似文献
986.
Mohammad Saleem 《代数通讯》2013,41(9):3227-3247
987.
Najmedin Azizi Alireza Khajeh-Amiri Hossein Ghafuri Mohammad Bolourtchian 《Molecular diversity》2011,15(1):157-161
An operationally simple and entirely green protocol for the synthesis of thiourea derivatives by the reaction of carbon disulfide
with primary amines in pure water is developed. This reaction is a highly atom-economic process for production of highly pure,
hindered thioureas without any catalyst and tedious work-up. 相似文献
988.
TiO 2 nanorods have been successfully grown into a track-etched polycarbonate (PC) membrane by a particulate sol-electrophoretic deposition from an aqueous medium.The prepared sols had a narrow particle size distribution around 17 nm and excellent stability against aging,with zeta potentials in the range of 47-50 mV at pH 2.It was found that TiO 2 nanorods were grown from dilute aqueous sol with a low,0.1-M concentration.Fourier transform infrared spectroscopy (FT-IR) analysis confirmed that a full conversi... 相似文献
989.
Morteza BararjanianSaeedeh Hosseinzadeh Saeed Balalaie Hamid Reza BijanzadehEckardt Wolf 《Tetrahedron letters》2011,52(26):3329-3332
An efficient palladium-catalyzed protocol for the stereoselective synthesis of 3-(aminoarylmethylene)-oxindoles has been developed. In this approach, Ugi-4-component reaction adducts were used as starting materials for carbopalladative cyclization-Buchwald reaction sequences. 相似文献
990.