Proceedings of the Indian Academy of Sciences - Section A

Shah, G.

doi: 10.1007/BF03049442pmid: N/A

Some size dependent resonances in the extinction efficiency by small metallic particles have been considered on the basis of the exact calculations on Mie Theory of Scattering. The results may be helpful in explaining some structures in the observed interstellar extinction curve and certain unidentified interstellar diffuse absorption bands.

Bagavant, G.; Patwardhan, B.

doi: 10.1007/BF03049443pmid: N/A

The ultraviolet spectra of α-carboxy and α-carbomethoxystilbenes obtained in the Claisen/Stobbe reaction of methyl phenyl acetate and aromatic aldehydes is reported. All these compounds possess the characteristiccis stilbene spectral curve. Electronic effects of substituents in the acid show characteristic bathochromic shifts. A fewtrans α-carboxystilbenes have been prepared and their spectra have the characteristictrans stilbene pattern.

Bagavant, G.; Patwardhan, B.

doi: 10.1007/BF03049444pmid: N/A

The ultraviolet spectra of methyl-α-o-carboxyphenyl cinnamates and α-o-carboxyphenylcinnamic acids is reported. These compounds possess the characteristiccis stilbene spectral curve, thereby supporting Loewenthal and Pappo’s suggestion that these compounds havecis Ph/Ph-COOR configuration. Formation of this isomer in the Stobbe reaction of dimethyl homophthalate and aryl aldehydes has been rationalized as proceedingvia the erythro conformer of the oxyanion.

Krishnan, T.; Nigam, Amar

doi: 10.1007/BF03049445pmid: N/A

The wavelengths of $$K_{\alpha _1 } , K_{\alpha _2 } , K_{\beta _1 } , K_{\beta _2 } , K_{\beta _2 } I and K_{\beta _2 } II$$ lines of heavy elements of atomic number 70–92 and the associated energy levels, K, LII, LIII, MII, MIII, NII and NIII have been calculated using a modified form of the relativistic energy formula of Sommerfeld, incorporating in it both the total and internal screening constants in a closed form. All the field theoretical corrections in the second and the fourth order as well as the finite nuclear size correction have been included.

Ramana Rao, V.; Sithapathi, A.

doi: 10.1007/BF03049446pmid: N/A

Exact solutions of the Navier-Stokes equations are derived by a Laplace-transform technique for two-dimensional, incompressible flow of an electrically conducting fluid past an infinite porous plate under the action of a transverse magnetic field subject to the conditions: (i) the magnetic Prandtl number Pm is unity, and (ii) the Alfven velocity is less than the suction velocity. It is assumed that the flow is independent of the distance parallel to the plate and that the velocity component normal to the plate is constant. General formulae are derived for the velocity distribution and the magnetic field in terms of the given external velocity. The skin-friction is obtained and some special cases are considered.