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711.
Aryldiazomethanes are converted by rhodium(II) acetate and iodorhodium(III) tetraphenylporphyrin to - rather than -1,2-diarylethylenes. Secondary aryldiazoalkanes react with rhodirum(II) acetate to give azines. 相似文献
712.
713.
Madan Rao Surajit Sengupta R. Shankar 《Physica E: Low-dimensional Systems and Nanostructures》1998,1(1-4)
The shape deformability of quantum-Hall skyrmions leads to a rich phase diagram in the
–g space. We study the long-wavelength physics of a collection of interacting skyrmions using a nonlinear sigma model. At zero temperature the ground state is crystalline with generalized Nèel order. As a function of the filling factor
, the skyrmion crystal undergoes a sequence of structural transitions driven by a change of shape of the individual skyrmions. Quantum effects lead to melting and orientational disordering transitions at high and low skyrmion densities, respectively. We show that moment of inertia of skyrmions also arises from the shape deformability of the skyrmions. 相似文献
714.
Shankar Prasad Mishra 《Proceedings Mathematical Sciences》1966,64(4):237-244
The inlet lengths in a straight channel and a circular tube by the laminar flow of an elastico-viscous liquid have been determined in this paper. Expressions for the inlet lengths have been obtained by the kinetic energy end correction method. For a given pressure drop, the elasticity of the liquid increases the inlet length only if the liquid possesses cross-viscosity. But cross-viscosity which decreases the inlet length has an independent effect on it. 相似文献
715.
716.
The problem of flow of an electrically conducting viscous liquid due to the time-varying motion of an infinite porous plate has been studied. There is a uniform magnetic field imposed transversely to the plate and the magnetic lines of force are taken to be fixed relative to the fluid. Exact solutions for the velocity field and the skin-friction have been obtained and some particular cases have been discussed. The effect of suction parameter and magnetic field strength on the flow characteristics have been depicted through several graphs and tables. 相似文献
717.
We consider the quantum stochastic dynamics of a system whose interaction with the reservoir is considered to be linear in bath co-ordinates but nonlinear in system co-ordinates. The role of the space-dependent friction and diffusion has been examined in the decay rate of a particle from a meta-stable well. We show how the decay rate can be hindered by inhomogeneous dissipation due to nonlinear system–bath coupling strength. 相似文献
718.
Raju Jannapu Reddy Angothu Shankar Md. Waheed Jagadeesh Babu Nanubolu 《Tetrahedron letters》2018,59(21):2014-2017
A convenient and metal-free protocol for the highly regioselective sulfonylation of NH-1,2,3-triazoles is described. A range of readily accessible NH-1,2,3-triazoles were sulfonylated with various aryl sulfinates in the presence of molecular iodine. The scope was extended to thiosulfonates as an efficient sulfonylating agent and nitrochromene derived triazoles were also explored for selective N-sulfonylation. A variety of synthetically viable N2-sulfonyl triazoles were obtained in moderate to high yields with excellent regioselectivities via N–S bond construction under mild reaction conditions. 相似文献
719.
AbstractA protocol based on Groebke-Blackburn-Bienayame (GBB) multicomponent reaction has been developed for efficient and atom economical synthesis of C-glucosides of 1-azaindolizine, i.e. 2-(β-D-glucopyranosyl)-3-N-alkylamino-1-azaindolizine. Thus, a series of fourteen novel 2-(β-D-glucopyranosyl)-3-N-alkylamino-1-azaindolizines have been synthesized in moderate to good yields by reaction of a perbenzylated β-C-glucopyranosyl aldehyde with differently substituted 2-aminopyridines and alkyl isocyanides using InCl3 as acid catalyst. All synthesized β-C-glucosides were unambiguously characterized with the help of spectroscopic (IR, 1H-NMR, 13C-NMR and mass spectra) data analysis. 相似文献
720.