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991.
Effect of different form of defects on phonon scattering in YIG have been studied. It has been found that defects in form of continuous lines behave like internal crystallite boundaries while weak sheet of defects scatter phonon like dislocations. 相似文献
992.
The mixed-ligand complexes, [Cux,(phen)yLz] (where phen stands for 1,10-phenanthroline and L for some aliphatic acids, aromatic acids, amino acids, phenols and ethylenediamine in the ratio 1 : 1 : 1 and 1 : 2 : 1) undergo two-step, diffusion-controlled, irreversible electro-reduction in 0.5 M KNO3 at the dropping mercury electrode. The double-wave nature of these complexes may be attributed to the adsorption effect of 1,10-phenanthroline. From the characteristics of the irreversible wave, the rate constant kf, for each complex has been calculated at its formal potential. The driving force for the formation of ternary systems has been analysed. The parent complex, [Cu(phen)] is found to show a discriminating nature towards the incoming secondary ligand. Additional stability effects compared to such systems with 2,2′-bipyridyl as the parent ligand have been explained on the basis of comparatively greater π-effects of 1,10-phenanthroline. Such effects are found t o become more pronounced, due to the cooperative effect, if the secondary ligand also has a π-system. 相似文献
993.
994.
Y. Srivastava A. Widom E. Sassaroli 《Zeitschrift fur Physik C Particles and Fields》1995,66(4):601-605
Relativistic propagators, the natural tools in field theory to describe the space-time development of a quantum system, are used to study correlations and interferences present in the neutral kaon system due to time-reversal violations. The method allows for a general wave-packet treatment of the problem. While standard results are obtained for singleK decays, quite different results are derived for the interference phase in two kaon decays such as those at DAΦNE. 相似文献
995.
Summary In this article, we obtain some sufficient conditions for weak convergence of a sequence of processes {X
n
} toX, whenX arises as a solution to a well posed martingale problem. These conditions are tailored for application to the case when the state space for the processesX
n
,X is infinite dimensional. The usefulness of these conditions is illustrated by deriving Donsker's invariance principle for Hilbert space valued random variables. Also, continuous dependence of Hilbert space valued diffusions on diffusion and drift coefficients is proved.Research supported by National Board for Higher Mathematics, Bombay, IndiaPart of the work was done at University of California, Santa Barbara, USA 相似文献
996.
997.
998.
999.
Srubabati Goswami Raghavan Rangarajan K. Agashe A. Bandyopadhyay K. Bhattacharya B. Brahmachari C. Burgess E. J. Chun D. Choudhury P. K. Das A. Dighe R. Godbole S. Goswami N. Gupta M. Kaplinghat D. Indumathi J. Forshaw Y. Y. Keum B. Layek D. Majumdar N. Mahajan P. Mehta R. N. Mohapatra N. Mondai S. More Y. Nir S. Pakvasa M. K. Parida M. Ravikumar G. Rajasekaran P. Ramadevi R. Rangarajan S. D. Rindani D. P. Roy P. Roy N. Sahu A. Samanta Y. Shadmi A. M. Srivastava S. Uma Sankar R. Vaidya U. Yajnik 《Pramana》2004,63(6):1391-1405
This is the report of neutrino and astroparticle physics working group at WHEPP-8. We present the discussions carried out
during the workshop on selected topics in the above fields and also indicate progress made subsequently. The neutrino physics
subgroup studied the possibilities of constraining neutrino masses, mixing and CPT violation in lepton sector from future
experiments. Neutrino mass models in the context of Abelian horizontal symmetries, warped extra dimensions and in the presence
of triplet Higgs were studied. Effect of threshold corrections on radiative magnification of mixing angles was investigated.
The astroparticle physics subgroup focused on how various particle physics inputs affect the CMBR fluctuation spectrum, and
on brane cosmology. This report also contains an introduction on how to use the publicly available code CMBFAST to calculate
the CMBR fluctuations. 相似文献
1000.
We show that cosmic strings moving through the plasma at the time of a first-order quark-hadron transition in the early universe
generate baryon inhomogeneities, which can survive till the nucleosynthesis epoch. We find out how these inhomogeneities actually
affect the calculated values of the light element abundances. Recently a wealth of observational data from various experiments
have helped to reduce the uncertainties in the values of these abundances. Using these we show that it is possible to derive
constraints in the presence of cosmic strings during the quark-hadron transition. 相似文献