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排序方式: 共有380条查询结果,搜索用时 142 毫秒
21.
Sujata Kashyap Udai P. Singh A. K. Singh Pravindra Kumar Shivendra Pratap Singh 《Transition Metal Chemistry》2013,38(5):573-585
The reaction of CuCl2·2H2O with 3,5-diisopropylpyrazole (PziPr2H) in the presence of sodium parafluorobenzoate (Na-p-FBz) resulted in the formation of an oxo-chloro-bridged tetranuclear complex [Cu4(PziPr2H)4(μ-O)(μ-Cl)6] 1, whereas the reaction of Cu(NO3)2·3H2O with PziPr2H in the presence of different benzoates gave [Cu(PziPr2H)2(μ-OCH3)]2(NO3)2 2, [Cu(PziPr2H)3(NO3)(p-ClBz)]·CH3CN 3, [Cu(p-CH3Bz)2(PziPr2H)]2·2CH3CN 4, [Cu(p-OCH3Bz)2(CH3CN)]2·4CH3CN 5 and [Cu(p-CNBz)(CH3CN)]2 6. Single-crystal X-ray diffraction studies confirmed these formulations. DNA binding studies for these complexes were performed by means of UV-visible absorption titration and viscosity measurements. Gel electrophoresis studies showed that hydroxyl radicals are involved in DNA cleavage in the presence of the complexes. 相似文献
22.
Surjeet Singh Ismail Althagafi Pratik Yadav Rahul Panwar Abhinav Kumar Ramendra Pratap 《Tetrahedron》2014
We have developed a base promoted simple, efficient and alternative approach for the synthesis of 4-amino-3-aroyl//heteroaroyl/acetyl-2-methylsulfanyl-naphthalene-1-carbonitriles by reaction of easily accessible 3,3-bis(methylthio)-1-aryl/heteroaryl/acetylprop-2-en-1-one and 2-cyanomethyl-benzonitrile. Reaction of 1-(2-halo/methoxy-phenyl)-3,3-bis(methylthio)prop-2-en-1-one and 2-cyanomethyl-benzonitrile under basic conditions also afforded 6-(methylthio)-7-oxo-7,12-dihydrobenzo[c]acridine-5-carbonitrile along with usual product. Structure of the synthesized product has been confirmed by single X-ray crystallography. 相似文献
23.
Jena Sudipta Ray Asit Sahoo Ambika Kamila Pradeep Kumar Nayak Sanghamitra Panda Pratap Chandra 《Chemistry of Natural Compounds》2021,57(6):1147-1149
Chemistry of Natural Compounds - 相似文献
24.
Pratap V Moumen N Subramanian RS 《Langmuir : the ACS journal of surfaces and colloids》2008,24(9):5185-5193
25.
K. Raghavendra Rao Akula Raghunadh Ramamohan Mekala Suresh Babu Meruva T.V. Pratap T. Krishna Dipak Kalita Eppakayala Laxminarayana Bagineni Prasad Manojit Pal 《Tetrahedron letters》2014
A dual reactant/catalyst role of glyoxylic acid in the reaction of isatoic anhydride with various amines afforded a novel, robust and rapid synthesis of 3-(un)substituted quinazolin-4(3H)-ones. This metal catalyst-free reaction proceeds via an unusual and unexpected cleavage of C–C bond. A shorter and common route to two alkaloids, that is, rutaecarpine and evodiamine is also accomplished. 相似文献
26.
K. J. Pratap M. Nagabhushanam F. M. Amanullah V. Hari Babu 《Crystal Research and Technology》1988,23(2):217-222
Thermal transport properties have been studied on as-grown and annealed CdTe:Sb thin films of different thicknesses and concentrations of Sb. These films were prepared by sequential vacuum deposition of CdTe and Sb on clean and hot glass substrates held at 210 °C temperature at a constant rate of deposition. From these studies all the films were found to be p-type. It is also observed that the thermoelectric power increases with Sb concentgration, thickness of the film and with annealing process. Fermi-energy variation with temperature have been calculated on the basis of thermo emf data. All these results have been explained on the basis of defects introduced by Sb doping. 相似文献
27.
K. J. Pratap M. Nagabhushanam A. Balaramaiah V. Hari Babu 《Crystal Research and Technology》1987,22(10):1285-1288
Hall coefficient and dc conductivity measurements are made on p-type CdTe:Sb films grown by vacuum evaporation technique on glass substrate. The grain boundary potential barrier, which is found mainly to limit the mobility of carriers is calculated as a function of film thickness. The n-type conduction is found to dominate over p-type conduction above about 330 K. The ratio of electron to hole mobility is also calculated. 相似文献
28.
Synthesis,characterization and role of zero-valent iron nanoparticle in removal of hexavalent chromium from chromium-spiked soil 总被引:3,自引:0,他引:3
Chromium is an important industrial metal used in various products/processes. Remediation of Cr contaminated sites present
both technological and economic challenges, as conventional methods are often too expensive and difficult to operate. In the
present investigation, Zero-valent iron (Fe0) nanoparticles were synthesized, characterized, and were tested for removal of Cr(VI) from the soil spiked with Cr(VI). Fe0 nanoparticles were synthesized by the reduction of ferric chloride with sodium borohydride and were characterized by UV–Vis
(Ultra violet–Visible) and FTIR (Fourier transform infrared) spectroscopy. The UV–Vis spectrum of Fe0 nanoparticles suspended in 0.8% Carboxymethyl cellulose showed its absorption maxima at 235 nm. The presence of one band
at 3,421 cm−1 ascribed to OH stretching vibration and the second at 1,641 cm−1 to OH bending vibration of surface-adsorbed water indicates the formation of ferrioxyhydroxide (FeOOH) layer on Fe0 nanoparticles. The mean crystalline dimension of Fe0 nanoparticles calculated by XRD (X-ray diffraction) using Scherer equation was 15.9 nm. Average size of Fe0 nanoparticles calculated from TEM (Transmission electron microscopy) images was found around 26 nm. Dynamic Light Scattering
(DLS) also showed approximately the same size. Batch experiments were performed using various concentration of Fe0 nanoparticles for reduction of soil spiked with 100 mg kg−1 Cr(VI). The reduction potential of Fe0 nanoparticles at a concentration of 0.27 g L−1 was found to be 100% in 3 h. Reaction kinetics revealed a pseudo-first order kinetics. Factors like pH, contact time, stabilizer,
and humic acid facilitates the reduction of Cr(VI). 相似文献
29.
Silica chloride catalysted one pot cyclocondensation of aldehydes,ethyl acetoacetate and phenyl hydrazine leading to substituted pyrazoles has been reported. 相似文献
30.
Ram Manohar Yadav Dinesh Pratap Singh T. Shripathi O. N. Srivastava 《Journal of nanoparticle research》2008,10(8):1349-1354
We report the observations made on the synthesis and characterization of C–N nanotube blocks and Y-junctions in bamboo-like
C–N nanotubes. The C–N nanotube Blocks have been synthesized by pyrolyzing the mixture of silver nitrate acetonitrile solution
and ferrocene benzene solution. The structural/microstructural characterization of the as-synthesized material has been done
using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). X-ray photoelectron spectroscopic (XPS)
analysis has been carried out to confirm the presence of nitrogen in nanotubes. These investigations reveal the formation
of blocks of bamboo-like nanotubes having the dimension 300 × 200 × 30 μm and the diameter is 20–50 nm. We also observe the
formation of Y-junctions in bamboo-like nanotubes as we spray the acetonitrile ferrocene and AgNO3 mixture. The length of the synthesized Y-junction nanotube bundles is ~2 μm. Some more complex Ψ-shaped junctions are also
found to be present. The diameters of the Y-junction nanotubes is ~80 nm at the junction and 25–50 nm at the branches. 相似文献