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91.
I.B. Khriplovich 《Hyperfine Interactions》2000,127(1-4):365-371
Upper limits on the electric dipole moments (EDM) of elementary particles and atoms are presented, and their physical implications
are discussed. The implications following from the neutron and atomic experiments are of comparable interest. The nuclear
EDMs can be studied at ion storage rings, with the expected sensitivity much better than
. This would represent a serious progress in studies of the CP-violation problem.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
92.
A nonlinear (piecewise linear) optical transfer function for optical applications generally and isolator especially is introduced and a realization method for the introduced block based on array of two-port nonlinear ring resonators is proposed. The effect of system parameters on the transfer function is studied. The characteristics of the introduced nonlinear device such as the threshold value and the slope of linear part can be controlled using the coupling coefficients and ring lengths. We show that using our proposed idea, easily more than 30-dB isolation well over 3 THz can be obtained only with similar two rings. Also, insertion loss less than 1 dB can be obtained using optical amplifier between rings. The proposed circuit is compact (0.2 mm2) and easily can be integrated with semiconductor lasers as well as other integrated devices and systems. Finally, the analytical result for approximation of the threshold and slope of linear part is presented. 相似文献
93.
《代数通讯》2013,41(9):4291-4299
Abstract Marciniak and Sehgal (Marciniak, Z., Sehgal, S. K. (1997). Constructing free subgroups of integral group rings units. Proc. Amer. Math. Soc.125(4):1005–1009) constructed free subgroups in U(?[G]) whenever Ghas a non normal finite subgroup. In this paper we construct free subgroups in U(?[G]), where Gis a group whose subgroups are all normal. 相似文献
94.
95.
Gorenstein flatness and injectivity over Gorenstein rings 总被引:1,自引:0,他引:1
Let R be a Gorenstein ring.We prove that if I is an ideal of R such that R/I is a semi-simple ring,then the Gorenstein flat dimension of R/I as a right R-module and the Gorenstein injective dimension of R/I as a left R-module are identical.In addition,we prove that if R→S is a homomorphism of rings and SE is an injective cogenerator for the category of left S-modules,then the Gorenstein flat dimension of S as a right R-module and the Gorenstein injective dimension of E as a left R-module are identical.We also give some applications of these results. 相似文献
96.
To explain the long-term existence of Uranian narrow rings, we study the dynamical evolution of Uranian epsilon ring under
the influence of its two shepherding satellites: Cordelia and Ophelia. The model of planar-elliptic restricted three-body
problem is employed, in which the three bodies are Uranus, a satellite and a test particle. Dissipations due to interparticle
collisions are also taken into consideration. A mapping system has been obtained based on the differential equation system.
Numerical results show that only those particles originally lying in the libration region of the resonance can be shepherded.
The size of the libration region depends mainly on the orbital eccentricity and mass of the shepherd satellite. For the outer
shepherd Ophelia with larger orbital eccentricity, if its mass is a third of the nominal mass 2.5 × 1019 g, most of the orbits are regular and the outer edge of the ring can be shepherded, but more fuzzy than the inner edge. Thus
we infer that Ophelia has a smaller mass. 相似文献
97.
The present paper focuses on the analysis of two- and three-dimensional flow past a circular cylinder in different laminar flow regimes. In this simulation, an implicit pressure-based finite volume method is used for time-accurate computation of incompressible flow using second order accurate convective flux discretisation schemes. The computation results are validated against measurement data for mean surface pressure, skin friction coefficients, the size and strength of the recirculating wake for the steady flow regime and also for the Strouhal frequency of vortex shedding and the mean and RMS amplitude of the fluctuating aerodynamic coefficients for the unsteady periodic flow regime. The complex three dimensional flow structure of the cylinder wake is also reasonably captured by the present prediction procedure. 相似文献
98.
Flux-flow voltage steps and negative differential resistivity in the cuprate Nd2−xCexCuOy are explained in terms of subbands between the Fermi energy and the energy gap affecting the quasiparticle dynamics. 相似文献
99.
100.
We give an elementary theory of Henselian local rings and construct the Henselisation of a local ring. All our theorems have an algorithmic content. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献