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21.
Virendra Singh Anita Rampal S. N. Biswas K. Datta 《Letters in Mathematical Physics》1980,4(2):131-134
The solution of a difference equation in the form of an infinite continued fraction is used to obtain a class of exact solutions for the eigenfunctions and eigenvalues of doubly anharmonic oscillators described by potentials of the type (1/2)2x2+(1/4)x4+(1/6)x6, n>0, provided certain constraints on the couplings are satisfied. The class is denumerably infinite but not complete. 相似文献
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Basudeb Datta 《Proceedings Mathematical Sciences》1994,104(2):385-388
A simplicial complex is said to satisfy complementarity if exactly one of each complementary pair of nonempty vertex-sets constitutes a face of the complex. We show that if a d-dimensional combinatorial manifold M with n vertices satisfies complementarity then d=0, 2, 4, 8, or 16 with n=3d/2+3 and |M| is a “manifold like a projective plane”. Arnoux and Marin had earlier proved the converse statement. 相似文献
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Zero-Sets of Quaternionic and Octonionic Analytic Functions with Central Coefficients 总被引:1,自引:0,他引:1
We prove that the zero set of any quaternionic (or octonionic)analytic function f with central (that is, real) coefficientsis the disjoint union of codimension two spheres in R4 or R8(respectively) and certain purely real points. In particular,for polynomials with real coefficients, the complete root-setis geometrically characterisable from the lay-out of the rootsin the complex plane. The root-set becomes the union of a finitenumber of codimension 2 Euclidean spheres together with a finitenumber of real points. We also find the preimages f1for any quaternion (or octonion) A. We demonstrate that this surprising phenomenon of complete spheresbeing part of the solution set is very markedly a special realphenomenon. For example, the quaternionic or octonionic Nthroots of any non-real quaternion (respectively octonion) turnout to be precisely N distinct points. All this allows us todo some interesting topology for self-maps of spheres. 相似文献
27.
H. Naik T. Datta S. P. Dange P. K. Pujari S. Prakash M. V. Ramaniah 《Zeitschrift für Physik A Hadrons and Nuclei》1988,331(3):335-342
In the present work angular momenta of the fragments corresponding to132Im,g have been deduced from the radiochemically determined independent isomeric yield ratios and statistical model based analysis in neutron induced fission of235U,239Pu and245Cm and spontaneous fission of252Cf. These data along with similar data on134I, reported earlier from this laboratory, bring out the effects of deformed 66n and spherical 82n shells on fragment angular momentum showing also an inverse correlation of the latter with elemental yields. Quantitative estimates of fragment scission point deformation and the coefficient of change of fragment angular momentum with kinetic/excitation energy have been deduced and are seen to be in good agreement with the expected theoretical estimates. 相似文献
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High temperature scanning tunneling spectroscopy (HT-STS) was used to investigate the electronic structure of Au(1 1 1) at different temperatures in the energy range 0-1 eV below the Fermi level. We concentrated on the influence of temperature on the Shockley surface state (SS) appearing on noble metals surface due to a surface projected bulk bang gap in [1 1 1] direction. The influence of temperature on the projected band gap edge (BE) was also investigated. The experiment was carried out in the temperature range 294-580 K. As the result of the experiment a delicate shift of the SS and the BE in direction of the Fermi level was reported. 相似文献
29.
An efficient and direct procedure for the synthesis of amidoalkyl-2-naphthol derivatives has been described. The process employs a three-component cyclocondensation reaction in one-pot using β-naphthol, aromatic aldehyde and acetamide or benzamide in the presence of silica chloride accelerated by ultrasound giving the product in excellent yield in very short duration. 相似文献
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