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1.
Antimony telluride thin films were prepared on the well-cleaned glass substrates under a pressure of 10 – 5 torr by thermal
evaporation method. The thicknesses of the films were measured using Multiple Beam Interferometer (MBI) technique. The structure
of the sample was analyzed by X-ray diffraction technique. The film attains crystalline structure as the temperature of the
substrate is increased to 373 K. The d spacing and the lattice parameters of the sample were calculated. Optical behavior
of the film samples with the various thicknesses was analyzed by obtaining their transmittance spectra in the wavelength range
of 400 – 800 nm. The transmittance is found to decrease with increase in film thickness and also it falls steeply with decreasing
wavelength. The optical constants were estimated and the results are discussed. The optical band gap energy decreases with
increase in the film thickness. The optical transition in these films is found to be indirect and allowed.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
2.
Fragmentation patterns resulting from electron impact ionization of 3-(2′-hydroxyethyl)quinolin-2(1H)-one, three of its monosubstituted derivatives and four of its disubstituted derivatives were studied. The molecular ion of quinolinone-2-etbanol undergoes initial fragmentation with the loss of OH·, H2O, CO, ·CHO, CH2O, CH2OH·, CH2?CHOH and HCNO species. The [M – CHO]+ ion is tentatively suggested to have been formed by the expulsion of H· from the [M – CO]+· ion and the [M - CHO]+ peak may be considered as diagnostic of a 2-quinolone-3-ethanol. 相似文献
3.
A new and convenient synthesis of 2-isopropylfuro-(2,3-b)quinolines () from 3-(3-methylbut-1-enyl)-2-quinolones () is described. A neat synthesis of the alkaloids (±)-lunacrine (), (±)-lunasine () and (±)-demethoxylunacrine () is also reported. 相似文献
4.
[reaction: see text] A novel and powerful reagent system R(3)Al-R'(3)SiOTf for the one-pot alkylation-silylation reaction of epoxides was discovered, and the reactions of various epoxides with the new reagent system have been demonstrated to occur stereospecifically giving rise to the corresponding alkylation-silylation products in excellent yields. 相似文献
5.
Raquel Simancas Anand Chokkalingam Shanmugam P. Elangovan Zhendong Liu Tsuneji Sano Kenta Iyoki Toru Wakihara Tatsuya Okubo 《Chemical science》2021,12(22):7677
Zeolites have been successfully employed in many catalytic reactions of industrial relevance. The severe conditions required in some processes, where high temperatures are frequently combined with the presence of steam, highlight the need of considering the evolution of the catalyst structure during the reaction. This review attempts to summarize the recently developed strategies to improve the hydrothermal framework stability of zeolites.This review attempts to summarize the recently developed strategies to improve the hydrothermal framework stability of zeolites. 相似文献
6.
Shanmugam Kotteswaran Sundaramoorthy Kannadhasan Perumalsamy Ramasamy 《Journal of Solid State Electrochemistry》2021,25(7):1949-1958
Journal of Solid State Electrochemistry - The phenyl-conjugated oligoene dye 2-cyano3-(4-diphenylaminophenyl)prop-2-enoic acid (SKS) was synthesized by chemical method, and its structure was... 相似文献
7.
K. Meena K. Muthu M. Rajasekar V. Meenatchi S. P. Meenakshisundaram S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2013,112(2):1077-1082
Single crystals of tris(thiourea)silver(I) nitrate have been grown by slow evaporation solution growth technique from an aqueous solution at 25 °C. The single crystal X-ray diffraction study reveals that the crystal belongs to tetragonal system and cell parameters are a = b = 14.2790(4) Å, c = 24.8900(7) Å, and V = 5074.8(2) Å3. The various functional groups present in the molecule are confirmed by Fourier transformed infrared spectroscopy (FT-IR). The structure and the crystallinity of the materials were further confirmed by powder X-ray diffraction analysis. Thermogravimetric and differential thermal analysis reveal the purity of the sample and no decomposition is observed up to the melting point. The crystal is further characterized by UV–Vis and Vickers microhardness analysis. 相似文献
8.
Pitchiah Esakki Karthik Chinnaiah Jeyabharathi Shanmugam Senthil Kumar Kanala Lakshmi Narasimha Phani 《Journal of Solid State Electrochemistry》2013,17(12):3055-3061
It is shown that the gold surface is catalytically deactivated and smoothened upon removal of the Prussian blue (PB)–gold nanocomposite formed on the gold surface. Atomic force microscopy proves surface smoothening after PB removal. The voltammetric responses of Ru(NH3)6Cl3 on the smoothened surface remain unaffected, but the reactions that involve multistep and inner-sphere electron transfer are affected on the smoothened surface as exemplified by hydroquinone, ferrous oxalate redox reactions, and oxygen reduction. These effects are attributed to catalytic deactivation as a consequence of removal of the active sites. Figure
It is shown that the gold surface is catalytically deactivated and smoothened upon removal of the Prussian blue (PB)–gold nanocomposite formed on the gold surface. Atomic force microscopy proves surface smoothening after PB removal. The voltammetric responses of Ru(NH3)6.Cl3 on smoothened surface remain unaffected, but the reactions that involve multistep and inner-sphere electron transfer are affected on the smoothened surface as exemplified by hydroquinone, ferrous oxalate redox reactions, and oxygen reduction. These effects are attributed to catalytic deactivation as a consequence of removal of the active sites. Graphical abstract shows the Au surface smoothening as a consequence of Prussian blue-gold nanocomposite (Au-PB) formation and removal 相似文献
9.
The O-glycosidation reaction of 1-O-acetyl-2,3-dideoxy-DL-pent-2-enopyran - 4 -ulose catalysed by the environmentally accepted and inexpensive industrial catalyst Montmorillonite K-10 clay with variety of alcohols in high yield is reported. 相似文献
10.
M. Gopalakrishnan P. Sureshkumar V. Kanagarajan J. Thanusu Shanmugam Govindan Mahesh Reddy Ghanta 《合成通讯》2013,43(13):1923-1926
The p‐toluenesulphonic acid–catalyzed reaction between appropriate cresols and N‐methyl‐3‐phenyl‐3‐hydroxypropylamine in refluxing toluene resulted in the formation of o‐substituted phenol derivatives by an aromatic nucleophilic substitution reaction. 相似文献