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51.
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53.
Aniruddha Das 《合成通讯》2017,47(23):2254-2267
Investigation into Sonogashira reaction on 5-iodo-1-(phenyl/p-halophenyl)imidazole-4-carbonitrile compounds had been developed by introducing an iodo atom at the C-5 position of the imidazole ring of 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carbonitrile compounds. Specifically, 5-iodo-1-(4-iodophenyl)imidazole-4-carbonitrile compound had shown double Sonogashira coupling reactions with two differently substituted iodine along with the formation of two other compounds where an unusual coupling product with self-aggregation property was obtained. In other cases, monocoupling had been observed together with another compound where iodine atom present at C5 position of imidazole was replaced by hydrogen atom. 相似文献
54.
Indubhusan Deb 《Tetrahedron letters》2010,51(22):2945-6587
Cyclic amines and 1,3-diketones readily react under microwave irradiation to form ring-fused pyrroles in a single operation. A competing retro-Claisen pathway is efficiently suppressed by employing p-toluenesulfonic acid as an additive. 相似文献
55.
Himanshu Srivastava Pragya TiwariA.K. Srivastava Sanjay RaiTapas Ganguli S.K. Deb 《Applied Surface Science》2011,258(1):494-500
The effect of texture of iron foil substrate on the growth of hematite nanowires by annealing method has been investigated in detail. Three substrates of different textures were prepared from a [2 0 0] oriented iron foil by some simple processes. The hematite nanowires on these substrates were synthesized by annealing iron foil at 700 °C in moist oxygen. The growth pattern of nanowires on these substrates showed that the growth of hematite nanowires depends strongly on the iron substrate texture and [1 1 0] oriented iron grains are necessary for their growth. The samples were characterized by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), Electron Back Scatter Diffraction (EBSD) and Raman Spectroscopy. We have also tried to explain the various observations on the mechanism of growth. Mainly, the presence of water vapor significantly enhanced the formation of hematite nanowires which resulted in a very dense and aligned growth of nanowires on the substrate areas of favorable texture. Finally, the study proved the substrate texture to be a powerful tool to control growth of nanowires and can be used efficiently for patterning and large scale synthesis of the nanowires. 相似文献
56.
Aniruddha Kumar J.P. NilayaD.J. Biswas R.B. BhattMohd. Afzal J.P. PanakkalH.S. Kamath 《Applied Surface Science》2011,257(16):7263-7267
Pulsed laser assisted removal of uranium dioxide and thorium dioxide particulates from stainless steel surface have been studied using a TEA CO2 laser. Decontamination efficiency is measured as a function of laser fluence and number of pulses. Threshold fluence for the removal of UO2 particulates has been found to be lower than that required for the removal ThO2 particulates. Usage of a ZnSe substrate, that is transparent to the laser wavelength used here, enabled us to decouple the cleaning effect arising out of absorption in the particulates from that in the substrate and has contributed towards understanding the mechanism responsible for cleaning. The experimental observations are also corroborated by simple theoretical calculations. 相似文献
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58.
Dipak Ghosh Argha Deb Subrata Biswas Pasupati Mandal Asok Kumar Mallick Prabir Kumar Haldar 《Indian Journal of Physics》2009,83(10):1463-1485
This paper presents an investigation of compound hadrons (pions and protons) distribution emitted from 24Mg-AgBr and 12C-AgBr interactions both at 4.5 AGeV and 32S-AgBr interactions at 200 AGeV. The study includes azimuthal correlations (two particle and three particle), azimuthal asymmetry
and fractal behaviour. This paper reveals some interesting results. 相似文献
59.
We define equivariant cyclic and Hochschild cohomology modules of a cyclic objectX in the category ofG-sets and relate them with the Bredon cohomologies of the cyclic geometric realization |X|cy. 相似文献
60.
A time-dependent generalized non-linear Schr?dinger equation (GNLSE) of motion was earlier derived in our laboratory by combining
density functional theory and quantum fluid dynamics in three-dimensional space. In continuation of the work reported previously,
the GNLSE is applied to provide additional knowledge on the femtosecond dynamics of the electron density in the hydrogen molecule
interacting with high-intensity laser fields. For this purpose, the GNLSE is solved numerically for many time-steps over a
total interaction time of 100 fs, by employing a finite-difference scheme. Various time-dependent (TD) quantities, namely,
electron density, ground-state survival probability and dipole moment have been obtained for two laser wavelengths and four
different intensities. The high-order harmonics generation (HHG) is also examined. The present approach goes beyond the linear
response formalism and, in principle, calculates the TD electron density to all orders of change.
Dedicated to Prof. D Mukherjee on his 60th birthday 相似文献