No abstract available

No abstract available

[en] India is the only country in the world which is employing small sized nuclear reactors for its nuclear power programme. It has now embarked on a programme of augmenting the contribution of the nuclear power by way of employing both medium and small sized nuclear reactors in the next 15 years. This paper discusses the Indian experience and its efforts for industrial mobilisation for rapidly constructing 235/500 MWe nuclear reactor units in a period of about 8 to 9 years. The current energy situation in India and this context the near term role of nuclear power for supplementing the existing sources of commercial energy have been evaluated. Nuclear power has reached such a stage of maturity whereby it has now become a commercially viable source of electricity and it could be utilised on large scale to bridge the energy gap. At present six reactor units of 210/235 MWe capacity are in operation and eight more are in different stages of construction. While we are continuing with the construction of 235 MWe units, a programme of being pursued to construct 550 MWe capacity reactor units from midnineties onwards. This has become possible with the strengthening of regional electricity grids and simultaneous efforts undertaken for augmentation of fuel supply, heavy water production and industrial infrastructure. For a developing country like India, implementation of a sizable nuclear power programme has posed certain special challenges as major inputs are required to be made available with indigeneous efforts. This paper discusses such challenges and presents the ways and means adopted to surmount them. Other developing countries with conditions comparable to those in India could benefit from Indian experience in this regard. This paper also proposes India's willingness to cooperate with other countries for exchange of information and assistance in terms of technical knowhow. (author)

[en] Differential cross section results are calculated for the elastic scattering of electrons and positrons from the ground state of Rb and Cd atoms. An optical model potential approach is used for the calculation. Results are compared with the available electron impact experimental results

[en] Superelastic electron-atom scattering experiments are often more desirable to perform than inelastic experiments, in part due to the ability to excite specific fine-structure (and hyperfine-structure) states with relative ease. The superelastic scattering parameters measured, however, are often compared with inelastic parameters which have been measured or calculated by other groups, even though the two cases are not exactly the time-reverse of each other (inelastic experiments cannot resolve hyperfine-structure states). To do this there must exist a theoretical framework by which the various parameters for the two cases can be compared. In the non-relativistic limit a general framework has been developed for n'p → ns transitions in quasi one-electron atoms. The authors extend these calculations to the relativistic case where jj-coupling, rather than LS-coupling, is employed. Examples of calculations using the relativistic distorted-wave approximation will be given

[en] The data published over the past 15 years on the search for newer anticonvulsant drugs are generalized. Pyrrolidinedione, quinazolinone, xanthone, hydrazine and thiadiazole derivatives manifesting anticonvulsant activity in model in vivo tests in rodents are considered.

[en] The method due to Crothers and McCarroll is extended to study the resonance and nonresonance excitations in the neutral alkali atoms by impact of heavy projectiles (viz. H⁺, H₂⁺, H₃⁺, He⁺ and He²⁺). Total and differential cross sections are obtained for Li(2s ≥ 2p, 3s, 3p, 3d), Na(3s ≥ 3p, 3d) and K(4s ≥ 4p). In addition, the polarization fraction (π) of the transition as well as the alignment parameter (A₂₀) of the excited state in case of resonance excitations are calculated. The results obtained are compared with the other available theoretical and experimental results. The method is found to give quite reasonable description of the collisional processes considered. (author). 14 figs., 43 refs

[en] A distorted wave method has been used to calculate the total cross section results for the positron impact excitation of some one- and two-electron ionic systems (He⁺, Li⁺, Be^3+,2+, C^5+,4+, O^7+,6+ and Ne^9+,8+). The distortion due to static and polarisation potentials is incorporated in the projectile distorted waves of both the initial and final channels. For an He⁺ ion, present results are compared with the only available close-coupling results. (author)

[en] A distorted-wave calculation is performed for the integrated Stokes parameters for the radiation emitted from the polarized sodium (3²P_3/2,1/2 → 3²S_1/2) and potassium (5²P_3/2,1/2 → 4²S_1/2) atoms. The results are obtained in the energy range of 5-200 eV and these, when compared with the recently reported experimental data of Bukhari et al, are found to show an overall good agreement. (author)

[en] Recent measurements have been made of the integrated Stokes parameters for the light emitted following the excitation of the np⁵ (n+1)p[5/2]₃ (³D₃) state of the noble gases by spin-polarized electrons. These measurements give direct information on the spin-orbit coupling effects on the scattered electron. Hence it is of considerable interest to compare these data with the results of a completely relativistic distorted-wave treatment of these collisions which includes the relativistic interactions of the scattered electron to all orders. Results in this approximation are presented for the excitation of argon, krypton and xenon. (author)