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41.
The reaction of aryl-substituted propargyl alcohols possessing o-nitro and o-alkylidene groups with (RO)(2)PCl afford novel phosphono(tetrahydro)dibenzazepines, N-hydroxyindolinones or polycyclics (including one with three fused four-membered rings). 相似文献
42.
M. S. Malashetty I. S. Shivakumara Sridhar Kulkarni Mahantesh Swamy 《Transport in Porous Media》2006,64(1):123-139
The linear stability of a viscoelastic fluid saturated densely packed horizontal porous layer heated from below and cooled
from above is investigated by considering the Oldroyd-B type fluid. A generalized Darcy model, which takes into account the
viscoelastic properties, is employed as momentum equation and a two-field model is used for energy equation each representing
solid and fluid phases separately. Linear stability analysis suggests that, there is a competition between the processes of
viscous relaxation and thermal diffusion that causes the first convective instability to be oscillatory rather than stationary.
Analytical expression for the occurrence of oscillatory onset is obtained, and it is found that the necessary condition for
the existence of the same is Λ < 1. Besides, the effect of viscoelastic parameters and the thermal non-equilibrium on the
stability of the system is analyzed. 相似文献
43.
Some applications of Briot—Bouquet differential subordination are obtained which improve or extend a number of classical results
in the univalent function theory. 相似文献
44.
Indoles react smoothly with sulfonyl chlorides in the presence of a catalytic amount of indium tribromide at ambient temperature to afford the corresponding 3-arylsulfonyl indole derivatives in high yields with high regioselectivity. 相似文献
45.
A new anthracene derivative bearing two phenylboronic acid groups at the 1,8-positions was prepared and its binding properties towards sorbitol, xylitol, fructose, glucose and galactose have been studied using fluorescence analysis. 相似文献
46.
The total hadronic cross section for e+e− annihilation between 3.1 and 4.8 GeV center of mass energy
J. Burmester L. Criegee H.C. Dehne K. Derikum R. Devenish J.D. Fox G. Franke G. Flügge Ch. Gerke G. Horlitz Th. Kahl G. Knies M. Rössler S. Wolff R. Schmitz T.N. Ranga Swamy U. Timm K. Wacker 《Physics letters. [Part B]》1977,66(4):395-400
Using the solenoidal magnetic detector PLUTO, we have measured the total cross section for e+e? annihilation into hadrons. Results are presented for center of mass energies between 3.6 and 4.8 GeV, and in the regions of the (3.1) and ψ(3.7) resonances. We also present results for the 2 prong cross section in the energy range 3.6 to 4.8 GeV. 相似文献
47.
Using the wave functions of the relativistic equivalent harmonic oscillator recently proposed, elastic electron scattering cross sections have been calculated in the Born approximation for helium and lead. Calculations have also been made with the non-relativistic isotropie oscillator wave functions. Comparison with high-energy electron scattering experiments shows that relativistic effects may be significant in a heavy nucleus like lead. 相似文献
48.
49.
Non-stoichiometry and isostructurality in a set of chiral phosphorus compounds as a result of lone pair/oxygen exchange, substantiated by the combined use of 31P NMR spectroscopy and X-ray crystallography, is described. 相似文献
50.