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991.
992.
Mohan Joshi 《Proceedings Mathematical Sciences》1988,98(1):63-69
In this paper we obtain a solvability result for random elliptic boundary value problem. Our result extends Browder's [2] main theorem to the random case. We use author's [4] fixed point theorem for this purpose. 相似文献
993.
994.
S. G. Joshi N. D. Ghatge J. P. Jog S. J. Walzade S. V. Bhoraskar 《Journal of Polymer Science.Polymer Physics》1983,21(5):685-697
Electron-beam-induced conductivity (EBIC) studies were carried out on fluorinated ethylene propylene copolymer (FEP) and its acrylonitrile graft copolymer (FEP-g-AN). The current transport parallel to the surface under the influence of an electron beam of medium energy (6–30 keV) is reported. The gain in EBIC is calculated and its characteristic variation as a function of beam energy is studied. Minima in the gain versus energy curves have been obtained around 21 keV for FEP, 12 and 18 keV for FEP-g-AN, and 12 keV for polyacrylonitrile (PAN). This behavior is explained by assuming the existence of electron trapping bands close to the surface, at characteristic distances below the surface of the polymeric film corresponding to the range of incident electrons. Gains of the order of 5, 12, and 30 have been obtained respectively for FEP, FEP-g-AN, and PAN for the maximum energy of incident electrons used. 相似文献
995.
The aggregation behaviour of a hydrotrope, sodiumn-butyl benzene sulfonate (Na-NBBS), in aqueous solutions is investigated by small-angle neutron scattering (SANS). Nearly
ellipsoidal aggregates of Na-NBBS at concentrations well above its minimum hydrotrope concentration were detected by SANS.
The hydrotrope seems to form self-assemblies with aggregation number of 36–40 with a substantial charge on the aggregate.
This aggregation number is weakly affected by the hydrotrope concentration. 相似文献
996.
Excitation and emission spectra of KCl : Tl phosphors having higher Tl content (Tl ≈ 0.01 m.f. and above) were examined with the help of Aminco-Bowman spectrophotofluorometer. Measurements also included the luminescence study of TlCl powder and TlCl solution. It is observed that there is parallelism in the excitation and emission spectra of heavily-doped KCl : Tl phosphor, TlCl powder and aqueous TlCl-solution. It is concluded that heavily-doped KCl : Tl phosphor contains undissociated TlCl molecules which act as luminescence centres. 相似文献
997.
A detailed examination of the luminescent characteristics of variously pretreated heavily doped NaBr:Tl phosphors has been carried out. A prominent emission band at 420 nm exhibited by the phosphor is attributed to the electronic transitions within Tl+ ion perturbed by the presence of another Tl+ ion occupying nearest neighbour alkali ion site, the centre so formed being known as dimer. It is rather surprising that the dimers are conspicuous by their absence in heavily doped NaCl:Tl phosphors. This aspect of the result is discussed on the basis of the relative sizes of the ions in the phosphors. 相似文献
998.
999.
The measurement of triplet decay time (τp) and the relative yields of phosphorescence to fluorescence (φp/φf) have been made in solutions of xanthene dyes. The value of φp/φf increases while that of τp decreases as the concentration of the solution is increased. The rate constants kp, kqp and kis have been estimated. It is found that the values of kqp and kis increase while that of kp remains substantially constant for the entire range of concentration. The deuterium solvent effect is observed in τp and φp. 相似文献
1000.
The possibility of the appearance of the ferromagnetism in the case of itinerant electrons in an amorphous system, is discussed by using the Hubbard model within the Hartree-Fock approximation. The corresponding system in its crystalline state is regarded to be paramagnetic. 相似文献