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911.
Time-dependent flows of rotating and stratified fluids in geometries with non-uniform cross-sections
K. C. Balan Rathna Devanathan A. Ramachandra Rao 《Proceedings Mathematical Sciences》1975,82(3):101-119
Unsteady rotating and stratified flows in geometries with non-uniform cross-sections are investigated under Oseen approximation using Laplace transform technique. The solutions are obtained in closed form and they reveal that the flow remains oscillatory even after infinitely large time. The existence of inertial waves propagating in both positive and negative directions of the flow is observed. When the Rossby or Froude number is close to a certain infinite set of critical values the blocking and back flow occur and the flow pattern becomes more and more complicated with increasing number of stagnant zones when each critical value is crossed. The analogy that is observed in the solutions for rotating and stratified flows is also discussed. 相似文献
912.
The polymerization of diallyl phthalate has been studied in two solvents, benzene (GRadical = 0.7) and chloroform (GR = 11.2), γ-radiation being used to investigate the effect of the solvent on the rates of polymerization and also chain transfer to the solvent. Kinetic analysis shows that in benzene solution the initiating species come almost exclusively from the monomer, but in chloroform they arise only from the solvent. The latter was further confirmed from the chlorine analysis of the polymer wherein chloroform appears to have telomerized with diallyl phthalate. In neither of the solvents was high molecular weight polymer obtained. The kp/kt1/2 for the polymerization of DAP was found to be 3.3 × 10?4 and 1.17 × 10?3 in benzene and chloroform solutions, respectively. The chain-transfer constant CS was 11.25 × 10?3 and 9.75 × 10?3 for benzene and chloroform, respectively. 相似文献
913.
S.Bhaskara Rao 《Discrete Mathematics》1977,17(3):225-233
Let G be a self-complementary graph (s.c.) and π its degree sequence. Then G has a 2-factor if and only if π - 2 is graphic. This is achieved by obtaining a structure theorem regarding s.c. graphs without a 2-factor. Another interesting corollary of the structure theorem is that if G is a s.c. graph of order p?8 with minimum degree at least , then G has a 2-factor and the result is the best possible. 相似文献
914.
915.
A. R. Patel K. V. Rao G. K. Shivakumar 《Applied Physics A: Materials Science & Processing》1981,24(1):85-88
A summary of the theoretical and experimental investigations carried out to understand the problem of epitaxy is given. The effect of deposition conditions and the nature of the substrate-deposit combination on the orientation of the final film is discussed. The importance of the nucleation and growth stages, reorientation and recrystallization effects and the influence of the impurities and defects in the substrate surface on the quality of the films deposited are presented. 相似文献
916.
917.
M. V. K. Appa Rao R. R. Daniel K. A. Neelakantan 《Proceedings Mathematical Sciences》1956,43(3):181-201
A study of nuclear disintegrations caused by α-particles of primary cosmic radiation with energies > 5 BeV per nucleon, has been carried out. In a systematic survey in nuclear emulsions using ‘along the track’ scanning method, 479 α-particles with a total track length of 40·84 metres and 242 interactions were obtained. From the angular distribution of shower particles associated with these interactions, a procedure has been found for distinguishing protons, which originally formed part of the incident α-particle and which have not taken part in the interaction, from other charged particles. The mean free path for nuclear interaction in G-5 emulsion is found to be 17·5±1·1 cm. (68·9±4·3 gm./cm.2). Assigning both to the incident α-particle and to the target nuclei a radius R=r oA1/2, one obtains an effective nuclear radiusr o=1·13±0·04 ×10?13 cm. Using the number of protons emerging from disintegrations of heavy nuclei (Silver and Bromine) without having participated in the interaction (as can be deduced from the angular distribution) and assuming spherical nuclei of uniform density, the mean free path of nucleons in nuclear matter is calculated to be less than 3·2×10?13 cm. 相似文献
918.
919.
920.
D. S. Surya Narayana R. B. Yadav P. R. Vasudeva Rao C. K. Mathews 《Journal of Radioanalytical and Nuclear Chemistry》1988,120(1):155-159
A radiochemical displacement method was utilized for the determination of traces of mercury in water taking advantage of its ability to displace cobalt from cobalt(III) diethyldithiocarbamate tagged with60Co. The method is found to be applicable in the concentration range of 50–200 g/ml mercury. The interfernces from various cations like Fe(III), Co(II), Cu(II), Pb(II) and Ag(I) ions were studied. 相似文献