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71.
Dipak Ghosh Argha Deb Swarup Ranjan Sahoo Kanchan Kumar Patra Prabir Kumar Haldar Jayita Ghosh 《Czechoslovak Journal of Physics》2002,52(6):789-794
An analysis of data of target fragments of 28Si-AgBr (at 14.5 AGeV) reveals the existence of emission asymmetry in the azimuthal plane, which is found to depend on the number of target fragments. The comparison with the data of 32S-AgBr (at 200 AGeV) and 16O-AgBr (at 60 AGeV) interactions indicates that emission asymmetry depends on the projectile mass and energy. 相似文献
72.
Pulak Ranjan Giri 《International Journal of Theoretical Physics》2008,47(6):1776-1783
The existence of bound state of the polarizable neutral atom in the inverse square potential created by the electric field
of a single walled charged carbon nanotube (SWNT) is shown to be theoretically possible. The consideration of inequivalent
boundary conditions due to self-adjoint extensions lead to this nontrivial bound state solution. It is also shown that the
scaling anomaly is responsible for the existence of such bound state. Binding of the polarizable atoms in the coupling constant
interval η
2∈[0,1) may be responsible for the smearing of the edge of steps in quantized conductance, which has not been considered so
far in the literature. 相似文献
73.
We have first obtained that the equations of equilibrium governing the finite radial expansion (contraction) and longitudinal
shearing of a circular cylindrical shell become uncoupled for a class of harmonic materials (a class of isotropic homogeneous
compressible elastic materials). Next it has been assumed that the dilatation is uniform. Following this the exact solutions
of the uncoupled equations of equilibrium have been obtained for a simple harmonic material which is reduced to the Neo-Hookean
material for the incompressible case. The deformation is nonhomogeneous in nature. The stresses have been obtained.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
74.
Alan R. Katritzky Akornsri Chermprapai Susana Bravo Ranjan C. Patel 《Tetrahedron》1981,37(21):3603-3607
The corresponding “pseudobase” Δ2 -1,5-diketones (8) and (14) afford dihydrochromenylium (9b) and tetrahydro-xanthylium monofluorides (15). These convert aryl- and heteroarylamines into dihydroquinolinium (10) and tetrahydro-acridinium (16) monofluorides which at 130–250° give the deaminated arenes and heteroarenes (average overall yield 60%). 相似文献
75.
Sengupta J Mukhopadhyay R Bhattacharjya A Bhadbhade MM Bhosekar GV 《The Journal of organic chemistry》2005,70(21):8579-8582
3,5'-ether-linked pseudooligopentose derivatives were synthesized for the first time from readily available carbohydrate precursors. The 1,2-isopropylidene-protected ether-linked oligopentoses are potentially important as precursors of novel RNA analogues. Intramolecular cycloaddition of the nitrile oxides prepared from these derivatives led to the diastereoselective formation of chiral isoxazolines fused to 10-16-membered oxacycles. The stereochemistry of some of these isoxazolines was established by X-ray diffraction and NOESY analysis. 相似文献
76.
Chattaraj PK González-Rivas N Matus MH Galván M 《The journal of physical chemistry. A》2005,109(25):5602-5607
77.
78.
Temporal evolution of local and global hardness during an ion-atom collision process has been studied within a quantum fluid
density functional framework. A dynamical variant of the maximum hardness principle has been found to be operative. Entropy
maximises in the encounter regime. Time dependence of density and its laplacian provides important insights into the collision
processvis-a-vis the hardness maximisation. 相似文献
79.
[reaction: see text] A divergent strategy for the synthesis of diverse azabicyclic ring systems has been developed in which a chiral N-allylpyrrolidine derivative, obtained from a carbohydrate precursor was converted to (-)-8-epi-swainsonine triacetate by RCM and to a pyrrolo[1,2-a]azepine derivative and a 3-hydroxymethyl-substituted indolizidine by N-allylcarbohydrate nitrone and nitrile oxide cycloadditions. 相似文献
80.