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61.
Kalkote Uttam Ramrao Choudhary Anil Ramkumar Natu Arvind Anant Ayyangar Nagaraja Ramanuja 《合成通讯》2013,43(10-11):1129-1135
1-Alkylaminoanthraquinones ( 2 a-f) and 1,4-bisalkylaminoanthraquinones ( 4 a-c) were prepared from aminoanthraquinones ( 1,3 ) by alkylation with alkyl sulphate/alkyl halide in presence of powdered sodium hydroxide, potassium carbonate and phase transfer catalyst. 相似文献
62.
M. Anil Kumar K. R. Kishore Kumar Reddy M. Veeranarayana Reddy C. Devendranath Reddy 《合成通讯》2013,43(13):2089-2095
An efficient and direct approach for the α-thiocyanation of ketones with α-hydrogens has been developed using ammonium thiocyanate as a thiocyanating agent and oxone as an oxidant in methanol. 相似文献
63.
1‐[(Substituted carbamoyl)amino]‐1H,3H‐1λ5‐[1,3,2]oxazaphospholo[3,4‐a]benzimidazol‐1‐ones were synthesized by reacting benzimidazole 2‐methanol (4) with different chlorides of carbamidophosphoric acids (3) in the presence of triethylamine at 40–45°C. Their 1H, 13C, and 31P NMR spectral data were discussed. The title compounds were tested for their activity against the fungi Aspergillus niger and Fusarium solani and bacteria Staphylococcus aureus and Escherichia coli. These compounds showed moderate antibacterial activity when compared with antifungal activity. 相似文献
64.
Sanjeev Kumar Aavula Anil ChikkulapalliN. Hanumanthappa Indira JyothiC.H. Vinod Kumar Sulur G. Manjunatha 《Tetrahedron letters》2013
A series of carboxylic acids were converted into their corresponding esters using the Pd/C catalyzed hydrogenation conditions in the presence of catalytic bromobenzene in alcohols and the method could also be applicable for the transesterification of esters. Good to excellent yields were obtained for different aliphatic or aromatic starting materials. The success of this esterification relies on the in situ generation of hydrobromic acid (HBr) from bromobenzene which provides a mild and acidic reaction environment. The palladium catalyst exhibits a remarkable activity and is reusable for up-to three consecutive cycles. 相似文献
65.
Demulsification of water-in-crude oil emulsion was studied at two different salinities, 0.5% and 10% sodium chloride, using five different nonionic surfactants. Equilibrium crude oil-water interfacial tension was measured with drop volume method. Low molecular weight surfactants were found to be completely ineffective as demulsifiers. Three surfactants which were effective demulsifiers, exhibited good interfacial activity, surface adsorption and surface pressure. The performance of the demulsifiers changed with change in salinity of aqueous phase. Surfactants effective as demulsifiers reduced surface tension of water by more than 25 dynes-cm-1. For a given crude oil-water system, the surfactant which developed surface pressure in excess of 15 dynes-cm-1 was found to be good demulsifier for that system. Based upon these studies, a physical model of demulsification has been proposed 相似文献
66.
Shashank Tripathi Achu Chandran Tilak Joshi Anil Kumar Ajay Dhar 《Liquid crystals》2013,40(9):1255-1262
In this article, a newly synthesised ferroelectric liquid crystal (FLC) material, namely LAHS 22, has been characterised. The characterisation of the FLC material has been performed using dielectric relaxation spectroscopy, differential scanning calorimetry and polarisation optical microscopy. We observed an enhancement in the dielectric and electro-optical properties of the FLC material by incorporating gold nanoparticles (GNPs)-decorated multiwalled carbon nanotubes (MWCNTs). The GNPs-decorated MWCNTs cause an increment in dielectric dispersion (up to kHz), absorption, spontaneous polarisation and rotational viscosity of the FLC material. The pure and GNPs-decorated MWCNTs doped FLC cells were analysed by means of various dielectric spectroscopic and optical measurements. The observed enhancement in the dielectric and electro-optical properties of the FLC material has also been studied with concentration of GNPs-decorated MWCNTs in FLC material. The GNPs-decorated MWCNTs/FLC composites are not only of fundamental importance, but also useful materials for device applications such as liquid crystal displays and memory devices. 相似文献
67.
Kyung Ju Lee Muhammad Salman Maqbool Pullur Anil Kumar Kwang Ho Song Heon Phil Ha 《Research on Chemical Intermediates》2013,39(7):3265-3277
Economic production of titanium dioxide (yield >98 %) from ilmenite has been achieved by use of a modified sulfate reduction process. A series of samples were prepared by varying the concentration of titanium dioxide nuclei (0.2, 0.3, and 0.6 %) and further impregnation with antimony and vanadia. The structural and acidic properties of the samples were comprehensively studied by X-ray diffraction (XRD), transmission electron microscopy, BJH pore size distribution, and temperature-programmed desorption of NH3. The XRD results revealed the presence of intense peaks from anatase titanium dioxide. Enhancement of surface area was observed for second-time filtered samples, possibly because of loss of iron from the bulk. As a result, formation of additional micropores was apparent from N2 adsorption and desorption isotherms. Among all the antimony and vanadia-doped samples, the first-time filtered sample with the low concentration of nuclei (0.2 %) had the highest catalytic activity at low temperatures, owing to its larger pore size and abundant acidic species. 相似文献
68.
G. Satish K. Harsha Vardhan ReddyK. Ramesh B.S.P. Anil KumarY.V.D. Nageswar 《Tetrahedron letters》2014
A simple and efficient, ligand-free C–N cross-coupling of aryl halides/benzyl bromides with trans-4-hydroxy-l-proline has been developed to produce aromatized N-substituted pyrroles, using a catalytic amount of magnetically separable and recyclable CuFe2O4 nanoparticles, in the presence of Cs2CO3 in DMSO at 100 °C. 相似文献
69.
The densities, ρ, refractive indices, n D, and ultrasonic speeds, u, of binary mixtures of acetonitrile (AN) with poly(ethylene glycol) 200 (PEG200), poly(ethylene glycol) 300 (PEG300) and poly(ethylene glycol) 400 (PEG400) were measured over the entire composition range at temperatures (298.15, 303.15, 308.15 and 313.15) K and at atmospheric pressure. From the experimental data, the excess molar volumes, \( V_{\text{m}}^{\text{E}} \) , deviations in refractive indices, \( \Delta n_{\text{D}} \) , excess molar isentropic compressibility, \( K_{{s , {\text{m}}}}^{\text{E}} \) , excess intermolecular free length, \( L_{\text{f}}^{\text{E}} \) , and excess acoustic impedance, Z E, have been evaluated. The partial molar volumes, \( \overline{V}_{\text{m,1}} \) and \( \overline{V}_{\text{m,2}} \) , partial molar isentropic compressibilities, \( \overline{K}_{{s , {\text{m,1}}}} \) and \( \overline{K}_{{s , {\text{m,2}}}} \) , and their excess values over whole composition range and at infinite dilution have also been calculated. The variations of these properties with composition and temperature are discussed in terms of intermolecular interactions in these mixtures. The results indicate the presence of specific interactions among the AN and PEG molecules, which follow the order PEG200 < PEG300 < PEG400. 相似文献
70.
Some new 4-(2,6-diarylpyridin-4-yl)-2H-chromen-2-one derivatives 5a–l have been synthesized by reacting 4-(3-oxo-3-arylprop-1-enyl)-2H-chromen-2-ones 3a–c with appropriate 1-(2-oxo-2-arylethyl)pyridinium bromide salt 4a–d in the presence of ammonium acetate in refluxing glacial acetic acid. The newly synthesized compounds have been characterized by elemental and spectral analysis. 相似文献