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991.
Liu N Mukherjee S Bao K Brown LV Dorfmüller J Nordlander P Halas NJ 《Nano letters》2012,12(1):364-369
The plasmonic properties of coupled metallic nanostructures are understood through the analogy between their collective plasmon modes and the electronic orbitals of corresponding molecules. Here we expand this analogy to planar arrangements of plasmonic nanostructures whose magnetic plasmons directly resemble the delocalized orbitals of aromatic hydrocarbon molecules. The heptamer structure serves as a benzene-like building block for a family of plasmonic artificial aromatic analogs with fused ring structures. Antiphase magnetic plasmons are excited in adjacent fused heptamer units, which for a linear multiheptamer structure is a behavior controlled by the number of units in the structure. This antiphase coupling gives rise to plasmonic "antiferromagnetic" behavior in multiple repeated heptamer structures, supporting the propagation of low-loss magnetic plasmons in this new waveguide geometry. 相似文献
992.
Mukherjee S Nagar S Mullick S Mukherjee A Saha A 《Journal of molecular graphics & modelling》2008,26(5):884-892
Considering the worth of developing non-steroidal estrogen analogs, the present study explores the pharmacophore features of arylbenzothiophene derivatives for inhibitory activity to MCF-7 cells using classical QSAR and 3D space modeling approaches. The analysis shows that presence of phenolic hydroxyl group and ketonic linkage in the basic side chain of 2-arylbenzothiophene core of raloxifene derivatives are crucial. Additionally piperidine ring connected through ether linkage is favorable for inhibition of breast cancer cell line. These features for inhibitory activity are also highlighted through 3D space modeling approach that explored importance of critical inter features distance among HB-acceptor lipid, hydrophobic and HB-donor features in the arylbenzothiophene scaffold for activity. 相似文献
993.
994.
Mritunjoy Prasad Ghosh Samrat Mukherjee 《Journal of the American Ceramic Society》2019,102(12):7509-7520
We have investigated the structural and magnetic properties of polycrystalline Cu-substituted cobalt ferrite (CuxCo1−xFe2O4: x = 0.00, 0.15, 0.30, 0.45, 0.60) nanoparticles, synthesized via chemical coprecipitation method. The prepared samples were of single phase as confirmed by X-ray diffraction analysis. The mean crystallite size ranged from 44 to 65 nm was obtained using Scherrer's formula. M-T curves revealed that the Curie temperature of all the samples was above room temperature and it was found to decrease with increasing Cu concentration, which was supported by Mössbauer spectra. Field cooled (FC) hysteresis curves showed ferrimagnetic nature at 5 K and room temperature. It was observed that careful variation of Cu concentration in cobalt ferrite lead to weak A-B interaction with tunable magnetic properties. 相似文献
995.
The present study deals with experimental investigation of cooling of machining tools, by water flowing through a microduct at the tip of the tool. The average diameter of the microduct is 200 μm and the flow takes place at a turbulent Reynolds number. The outer wall temperature of the tool and the temperature of water at inlet and exit have been measured. The convective heat transfer coefficient is calculated at different wall temperatures and mass flux. The experimental results show that the average Nusselt numbers in the short microduct are higher than those predicted by conventional correlations for large-diameter ducts. This enhancement may be attributed to the micro size of the duct, entry effects, transition from laminar to turbulent flow at the microduct entrance, suspended microscopic particles in coolant water, and Prandtl number estimation based on the mean fluid temperature. A correlation has been proposed to compute convective heat transfer during turbulent flow through a short microduct of a particular geometry for a range of Reynolds and Prandtl numbers. 相似文献
996.
Siddharth V. Patwardhan Niloy Mukherjee Stephen J. Clarson 《Journal of Inorganic and Organometallic Polymers》2001,11(2):117-121
The structure of amorphous silica determines its properties and governs its applications. Here we report the synthesis of elongated silica chains/rods on the nanometer size scale formed by the orientation of a growing silica sol. We have utilized a cationically charged synthetic organic polymer as a catalyst/template and perturbed the system by externally applied shear. It is proposed that the polymer orientation plays an important role in the formation of such morphologies. 相似文献
997.
998.
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1000.
Nanoporous rice husk derived carbon for gas storage and high performance electrochemical energy storage 总被引:1,自引:0,他引:1
Aswathi Ganesan Ritwika Mukherjee Jyotish Raj Manikoth M. Shaijumon 《Journal of Porous Materials》2014,21(5):839-847
We report on the gas storage behaviour and electrochemical charge storage properties of high surface area activated nanoporous carbon obtained from rice husk through low temperature chemical activation approach. Rice husk derived porous carbon (RHDPC) exhibits varying porous characteristics upon activation at different temperatures and we observed high gas uptake and efficient energy storage properties for nanoporous carbon materials activated even at a moderate activation temperature of 500 °C. Various experimental techniques including Fourier transform-infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy and pore size analyser are employed to characterise the samples. Detailed studies on gas adsorption behaviour of CO2, H2 and CH4 on RHDPCs have been performed at different temperatures using a volumetric gas analyser. High adsorption capacities of ~9.4 mmol g?1 (298 K, 20 bar), 1.8 wt% (77 K, 10 bar) and ~5 mmol g?1 (298 K, 40 bar) were obtained respectively for CO2, H2 and CH4, superior to many other carbon based physical adsorbents reported so far. In addition, these nanoporous carbon materials exhibit good electrochemical performance as supercapacitor electrodes and a maximum specific capacitance of 112 F g?1 has been obtained using aqueous 1 M Na2SO4 as electrolyte. Our studies thus demonstrate that nanoporous carbon with high porosity and surface area, obtained through an efficient approach, can act as effective materials for gas storage and electrochemical energy storage applications. 相似文献