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61.
Sreejarani?K.?Pillai Letlhogonolo?Matlhoko Chris?Arendse Suprakas?Sinha?Ray Mathew?Moodley 《Applied Physics A: Materials Science & Processing》2009,94(3):585-591
Multi-walled carbon nanotubes (MWCNTs) were synthesized a by chemical vapour deposition method. The effect of calcination
at temperatures ranging from 300 to 550°C in exposing the metal nanoparticles within the nanotube bundles was studied. The
degree of degradation of the structural integrity of the MWCNTs during the thermal process was studied by Raman spectroscopy,
X-ray diffraction analysis, field-emission scanning electron microscopy, and transmission electron microscopy. The thermal
behaviour of the as-prepared and calcined samples was investigated by thermogravimetric analysis. Calcination in air, at 400°C
for 1 h, was found to be an efficient and simple method to extract metallic impurities from the amorphous carbon shells with
minimal damage to the tube walls and lengths. The nanotubes were observed to be damaged at temperatures higher than 450°C. 相似文献
62.
Nagarajan Sathya Arumugam Manimaran Gunasekaran Raja Periyasamy Muthusamy Kandasamy Deivasigamani Chinnasamy Jayabalakrishnan 《Transition Metal Chemistry》2009,34(1):7-13
New mononuclear ruthenium(III) Schiff base complexes of the type [RuX2(EPh3)(L)] (X = Cl or Br; E = P or As; L = monobasic tridentate Schiff base derived from o-aminophenol or o-aminothiophenol with ethylacetoacetate or ethylbenzoylacetate) have been synthesized. The Schiff base ligands chelate to ruthenium
through O, N, and O/S by dissociation of the phenolic proton/thiophenolic proton forming chelate rings. These complexes have
been characterized by physico-chemical and spectroscopic methods. Cyclic voltammetric data of all the complexes showed Ru(III)/Ru(IV)
oxidation and Ru(III)/Ru(II) reduction within the range of 0–1.5 V and 0 to −1.5 V with respect to Ag/AgCl, respectively.
The complexes were tested as catalysts in the oxidation of alcohols using molecular oxygen at ambient temperature, and also
in C–C coupling reactions.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
63.
The thermal radiation energy is the clean energy with a much lower environmental impact than the conventional energy. The objective of the present work is to investigate theoretically the effect of copper nanoparticles and carbon nanotubes (CNTs) in the presence of base fluid (water) with the variable stream condition due to the thermal radiation energy. Single-walled carbon nanotubes (SWCNTs) in the presence of base fluid flow over a porous wedge play a significant role compared to those of copper nanoparticles on absorbing the incident solar radiation and transiting it to the working fluid by convection. 相似文献
64.
R. Kandasamy I. Muhaimin Norsarahaida S. Amin 《International Journal of Computational Fluid Dynamics》2013,27(1-2):1-11
This article concerns with a steady two-dimensional flow of an electrically conducting incompressible fluid over a vertical stretching sheet. A scaling group of transformations is applied to the governing equations. The system remains invariant due to some relations among the parameters of the transformations. Impact of thermophoresis particle deposition in the presence of temperature-dependent fluid viscosity plays an important role on the concentration boundary layer. The results thus obtained are presented graphically and discussed. 相似文献
65.
Arul Murugesan Robert M. Gengan Kandasamy G. Moodley 《Journal of the Iranian Chemical Society》2018,15(11):2573-2584
Derivatives of methyl piperazinyl–quinolinyl nicotinonitrile were synthesised by one-pot method under microwave conditions. This was achieved using the Knoevenagel condensation reaction. The novel derivatives described above were purified by column chromatography and characterised by FT-IR, 1H, 13C, 2D-NMR and HRMS spectroscopic techniques. Furthermore, molecular docking was used to determine the binding sites of DNA with selected compounds. The synthetic method developed in this study showed several advantages including simplicity, high yield of products, coupled with safety and a short reaction time of 15 min. 相似文献
66.
Kandasamy Ramasamy Roland K. Robins Ganapathi R. Revankar 《Journal of heterocyclic chemistry》1988,25(3):1043-1046
4-Amino-7-(2,3,5-tri-O-benzyl-β-D-arabinofuranosyl)pyrrolo[2,3-d]pyrimidine-5-carbonitrile ( 6a ), prepared from 2-ethoxymethyleneamino-5-bromopyrrole-3,4-dicarbonitrile ( 4 ), was debenzylated with boron trichloride to give ara-toyocamycin ( 6b ). Further functional group transformation of 6b provided a route to 4-amino-7-β-D-arabinofuranosylpyrrolo[2,3-d]pyrimidine-5-thiocarboxamide (ara-thiosangivamycin, 7a ), and the corresponding 5-carboxamidoxime 8a and 5-carboxamidine 8b derivatives. Phosphorylation of unprotected 7a with phosphorus oxychloride gave ara-thiosangivamycin 5′-monophosphate ( 7b ). 2′-O-Acetyl-ara-thiosangivamycin ( 10b ) was prepared as a prodrug by acetylation of 9a , followed by deprotection of the t-butyldimethylsilyl groups under acidic conditions without acyl migration. 相似文献
67.
68.
本文定义了一个新的代数系{R×C×S}这是一个有环结构的自由R-模,并讨论了结构性质与R的性质. 相似文献
69.
Ti(II)-mediated tandem cyclization of (E)-5-(tert-butyldimethylsilyloxy)-8-trimethylsilyl-2-octen-7-ynoate (7) prepared from commercially available optically active epichlorohydrin (2) proceeded diastereoselectively to provide 7-(tert-butyldimethylsilyloxy)-2-trimethylsilylbicyclo[3.3.0]oct-1-en-3-one (1), which serves as a useful chiral building block or intermediate to prepare a variety of compounds having a bicyclo[3.3.0]octane framework. 相似文献
70.
[reaction: see text] A general reversed approach is described to synthesize S-palmitoylated and S-farnesylated peptides via S(N)2 displacement of bromide by reaction of a thiol group containing lipid as nucleophile with bromoalanine-containing peptides as electrophile. By employing this approach, lipidated peptides, including characteristic partial structures of human Ras peptides, were synthesized in good yields. This method gives access to farnesylated, palmitoylated, and doubly lipidated peptides. 相似文献