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981.
982.
983.
Muhammad Shahid Muhammad Mazhar Mazhar Hamid Paul O' Brien Mohammad A. Malik Madeleine Helliwell 《应用有机金属化学》2010,24(10):714-720
Crystalline copper films were deposited by aerosol‐assisted chemical vapor deposition (AACVD) in the absence of hydrogen from two newly synthesized complexes [Cu(deae)(TFA)]4·1.25THF ( 1 ) and [Cu4(OAc)6(bdmap)2(H2O)2]·4H2O ( 2 ) [deae = N, N‐diethylaminoethanolate, TFA = trifloroacetate, OAc = acetate and bdmap = 1,3‐bis(dimethylamino)‐2‐propanolato]. These precursors were prepared in high yield using mixed ligands and crystallized in tetragonal and triclinic crystal systems with space groups 141/a and P ? 1. Complexes 1 and 2 thermally decomposed at 290 and 250 °C, respectively, to yield copper films which were characterized by SEM/EDX for their morphology and composition and PXRD for their crystallinity and phase. These films have smooth morphologies with particle sizes within the range of 0.3–0.6 µm and may find applications in fabrication of ultralarge‐scale integrated circuits. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
984.
Iraj Mohammadpoor-Baltork Hamid Reza Memarian Kiumars Bahrami 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2315-2321
A variety of aliphatic, aromatic, and heteroaromatic thiols were rapidly and cleanly converted to their corresponding disulfides in excellent yields using n-butyltriphenylphosphonium dichromate (BTPPDC) in acetonitrile solution under solvent-free conditions and microwave irradiation. Selective oxidation of thiols in the presence of other oxidizable functional groups, such as alcohol and sulfide, is a noteworthy advantage of this method. 相似文献
985.
N‐Nitrosation of different types of secondary amines has been proceeded using supported perchloric acid on silica gel and sodiume nitrite under heterogeneous conditions. The operational system is simple and high pure products can be easily isolated with good to high yields. 相似文献
986.
Tautomeric mixtures of 4-aryl substituted 5-acetyl-2-methoxydihydropyrimidines undergo oxidation by exposing to the UV-light under formation of sole pyrimidines. The nature of the 4-substitution and solvent, and the ratio of tautomeric mixtures affect the rate of reaction. A proposed electron transfer-induced photo-dehydrogenation supports the obtained results in this study. 相似文献
987.
Hassan Valizadeh F. Mahmoodi Kordi Hamid Gholipur Mohammad Amiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):3075-3081
Phosphoric acid imidazolium dihydrogenphosphate was found to work well as a catalyst and excellent reaction medium in the Pechmann condensation of substituted phenols or α-naphthol with ethyl acetoacetate to give 4-methyl coumarins under microwave irradiation. This method is simple, cost effective, requires short reaction times, and gives very good to excellent yields. 相似文献
988.
Mohammad Reza Ganjali Hamid Reza Sobhi Hadi Farahani Parviz Norouzi Rassoul Dinarvand Amir Kashtiaray 《Journal of chromatography. A》2010,1217(16):2337-2341
Solid drop based liquid-phase microextraction (SDLPME) is a novel sample preparation technique possessing obvious advantages of simple operation with a high pre-concentration factor, low cost and low consumption of organic solvent. SDLPME coupled with gas chromatography (GC), high-performance liquid chromatography (HPLC), and atomic absorption spectrometry (AAS) has been widely applied to the analyses of a different variety of samples. The basic principles, parameters affecting the extraction efficiency, and the latest applications of SDLPME are reviewed in this article. 相似文献
989.
The octane number is one of the characteristics of spark-ignition fuels such as gasoline. Octane number of fuels can be improved by addition of oxygenates such as ethanol, MTBE (methyl tert-butyl ether), TBF (tertiary butyl formate) and TBA (tertiary butyl alcohol) as well as their blends with gasoline that reduce the cost impact of fuels. Carbon nanotubes (CNTs) are as useful additives for increasing the octane number. Functionalized carbon nanotubes containing amide groups have a high reactivity and can react with many chemicals. These compounds can be solubilized in gasoline to increase the octane number. In this study, using octadecylamine and dodecylamine, CNTs were amidated and the amino-functionalized carbon nanotubes were added to gasoline. Research octane number analysis showed that these additives increase octane number of the desired samples. X-ray diffraction (XRD), Fourier transforms infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and thermal gravimetry analyses (TGA) were used for characterization of the prepared functionalized carbon nanotubes. 相似文献
990.
Francis R. Cooray Abdul-Kadir Hamid 《AEUE-International Journal of Electronics and Communications》2012,66(6):472-479
An exact analytic solution is presented to the problem of scattering from a coated perfect electromagnetic conducting (PEMC) elliptic cylinder, when it is illuminated by a plane wave as well as a line source. The problem is formulated by expanding the various fields in terms of appropriate angular and radial Mathieu functions and a set of expansion coefficients. The expansion coefficients associated with the incident fields are known, but those associated with the scattered fields and the fields within the coating are unknown. Imposing boundary conditions at the surface of the PEMC elliptic cylinder and the surface of the coating, enables the determination of the unknown expansion coefficients. Results are presented in the form of normalized scattering widths for elliptic cylinders of various sizes, PEMC admittances, and different coatings, to show the effects of these on scattering. 相似文献