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51.
Electrical noise associated with ion transport (termed as “ionic noise”) has been measured at different temperatures, using
a lock-in amplifier and dynamic signal analyzer for a polymer electrolyte PEO:NH4I and its CdS dispersed composite. The ionic noise suddenly increases as the polymer passes through its phase transition at
T
g and T
m. The T
g-peak in the noise measurement appears more clearly than what it does in DTA/DSC or conductivity measurements. Therefore,
we suggest the noise technique as a good probe for studying phase transitions in ion conducting solid electrolytes. Further,
the present noise measurements also confirm the known results of DTA/DSC studies that both T
g and T
m of polymer electrolytes shift on the formation of composites. 相似文献
52.
Plane wave Born approximation with Coulomb, relativistic and exchange corrections is employed to obtain L1-, L2- and L3-subshell ionization cross sections of several atoms due to electron and positron impacts for projectile energy varying from the threshold of ionization to 60 times the threshold energy. Photoionization cross sections for all the three L-subshells of the atoms are also calculated using the hydrogenic approximation for the atomic wave functions. For L3-subshell the present cross sections due to electron impact are in good agreement with a number of experimental data for different atoms over the entire energy range investigated. For L1- and L2-subshells the present calculations yield qualitative agreement with the experimental data. The agreement between the present results and the limited experimental data for positron impact is also satisfactory. The hydrogenic approximation for the L-subshell photoionization is found to be good at small photon energies but it underestimates the cross sections at large photon energies. 相似文献
53.
Avinash Khare 《Pramana》1997,48(2):537-553
We, offer an alternative interpretation of the Riemann zeta functionζ(s) as a scattering amplitude and its nontrivial zeros as the resonances in the scattering amplitude. We also look at several
different facets of the phase of theζ function. For example, we show that the smooth part of theζ function along the line of the zeros is related to the quantum density of states of an inverted oscillator. On the other
hand, for ℜs>1/2, we show that the memory of the zeros fades only gradually through a Lorentzian smoothing of the delta functions. The
corresponding trace formula for ℜs≫1 is shown to be of the same form as generated by a one-dimensional harmonic oscillator in one direction along with an inverted
oscillator in the transverse direction. Quite remarkably for this simple model, the Gutzwiller trace formula can be obtained
analytically and is found to agree with the quantum result. 相似文献
54.
The simplest formulas connecting Jacobi elliptic functions with different modulus parameters were first obtained over two
hundred years ago by John Landen. His approach was to change integration variables in elliptic integrals. We show that Landen’s
formulas and their subsequent generalizations can also be obtained from a different approach, using which we also obtain several
new Landen transformations. Our new method is based on recently obtained periodic solutions of physically interesting non-linear
differential equations and remarkable new cyclic identities involving Jacobi elliptic functions. 相似文献
55.
56.
57.
Khare A 《Physical review D: Particles and fields》1992,46(6):R2287-R2289
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