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111.
Debadi Chakraborty Mohit Bajaj Leslie Yeo James Friend Matteo Pasquali J. Ravi Prakash 《ournal of non Newtonian Fluid Mechanics》2010,165(19-20):1204-1218
We compute the flow of three viscoelastic fluids (Oldroyd-B, FENE-P, and Owens blood model) in a two-dimensional channel partly bounded by a tensioned membrane, a benchmark geometry for fluid–structure interactions. The predicted flow patterns are compared to those of a Newtonian liquid. We find that computations fail beyond a limiting Weissenberg number. Flow fields and membrane shape differ significantly because of the different degree of shear thinning and molecular extensibility underlying the three different microstructural models. 相似文献
112.
Brotati Chakraborty 《Journal of luminescence》2009,129(1):34-39
The interaction of bovine serum albumin (BSA) with proflavin was investigated by spectroscopic tools like absorption and fluorescence spectroscopy as well as laser flash photolysis. Absorption spectroscopy proved the formation of ground-state BSA-proflavin complex. Proflavin was found to quench the intrinsic fluorescence of BSA via static quenching. High value of quenching constant suggested that energy transfer occurred from BSA to proflavin. Distance between the fluorophore in the protein and the ligand (proflavin) was evaluated. Binding constant and number of binding site were determined for proflavin-BSA interaction both in phosphate buffer (pH∼6.8) and in sodium dodecylsulphate media. The values of the thermodynamic parameters suggested that the key interacting forces are van der Waal's interaction and hydrogen bonding. Laser flash photolysis study reconfirmed the formation of complex between BSA and proflavin. 相似文献
113.
When contributors to a common cause (or public good) are uncertain about each others’ valuations, early contributors are likely
to be cautious in free-riding on future contributors. Contrary to the case of complete information, when contributors have
independent private valuations for the public good, the expected total contribution generated in a sequential move game may
be higher than in a simultaneous move game. This is established in a conventional framework with quasi-linear utility where
agents care only about the total provision of the public good (rather than individual contribution levels) and there is no
non-convexity in the provision of the public good. We allow for arbitrary number of agents and fairly general distribution
of types. 相似文献
114.
Rüdel A Hentges R Becker U Chakraborty HS Madjet ME Rost JM 《Physical review letters》2002,89(12):125503
The dynamics of the photoionization of the two outermost orbitals of C(60) has been studied in the oscillatory regime from threshold to the carbon K edge. We show that geometrical properties of the fullerene electronic hull, such as its diameter and thickness, are contained in the partial photoionization cross sections by examining ratios of partial cross sections as a function of the photon wave number in the Fourier conjugated space. Evaluated in this unconventional manner photoemission data reveal directly the desired spatial information. 相似文献
115.
Sandeep Sundriyal Smriti Khanna Rikta Saha Prasad V. Bharatam 《Journal of Physical Organic Chemistry》2008,21(1):30-33
This theoretical study attempts to find out similarity between metformin and glitazone class of antidiabetic drugs. It was found that some tautomeric forms of both metformin and thiazolidinedione ring of glitazones have similar molecular electrostatic potential (MESP) surface and may bind to a common complementary surface. Complexation and docking studies were also carried out in order to support this hypothesis. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
116.
SU(6) ? SU(4) tensor decomposition of effective interactions in the 2s-1d shell has been carried out to examine the relative importance of the various irreducible tensors in many-particle spaces. For this purpose norms of the irreducible tensors are evaluated in many-particle spaces. Variation of the expectation value of the square of the irreducible tensor parts with excitation energy has also been examined using the polynomial expansion method. A new measure of symmetry breaking that is theoretically more sound is derived which includes in its definition partial width as well as internal width. This is used to study SU(4) symmetry mixing in nuclei. 相似文献
117.
118.
We demonstrate here that the dipole-allowed optical absorption spectrum of a parabolic quantum dot subjected to an external magnetic field reflects the interelectron interaction effects when the spin-orbit (SO) interaction is also taken into account. We have investigated the energy spectra and the dipole-allowed transition energies for up to four interacting electrons parabolically confined, and have uncovered several novel effects in those spectra that are solely due to the SO interaction. 相似文献
119.
Gharah N Chakraborty S Mukherjee AK Bhattacharyya R 《Chemical communications (Cambridge, England)》2004,(22):2630-2632
A combination of the newly synthesized and structurally characterized compound, [MoO(O2)2(saloxH)](saloxH2= salicylaldoxime) as catalyst, H2O2 as terminal oxidant and NaHCO3 as co-catalyst when stirred in CH3CN (10 cm3) at room temperature (rt) shows a very pronounced efficiency epoxidation of olefinic compounds, the method being green and economical. 相似文献
120.
Anirudh Pradhan Purnima Pandey Kanti Jotania Mahesh Kumar Yadav 《International Journal of Theoretical Physics》2007,46(11):2774-2787
Plane symmetric viscous fluid cosmological models of the universe with a variable cosmological term are investigated. The
viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density whereas the coefficient of shear
viscosity is to be proportional to rate of expansion in the model. We have also obtained a special model in which the shear
viscosity is assumed to be zero. The cosmological constant Λ is found to be a decreasing function of time and a positive which is supported by results from recent supernovae Ia observations.
Some physical and geometric properties of the models are also discussed. 相似文献