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941.
A relativistic model of independent quarks based on Dirac equation with an equally mixed scalar-vector square root confining
potential is used to compute the quark core contributions to the static properties like magnetic moments, charge radii and
axial vector coupling constant ratios of the baryon octet. The results obtained with appropriate corrections due to centre-of-mass
motion agree fairly well with experimental values. The model is also extended to the study of magnetic moments of the quark
core of baryons in the charmed andb-flavoured sectors and the overall predictions so obtained compare well with other model predictions. 相似文献
942.
943.
The thermoluminescence of x-irradiated CaSO4: Dy phosphors has been studied for diverse activator concentrations. The concentration-dependence of these phosphors on the
increase of glow peak intensities has been found to be remarkable. For higher concentration of dysprosium the concentration
quenching effect has been observed. This has been attributed to the resonant transfer of energy from one activator atom to
another, bringing the possible migration of energy in a solid, which is likely to get dissipated without luminescence, at
the quenching site itself. The effect of irradiation time on the glow peak intensities reveals the initial linearity and a
subsequent decrease indicating the possible radiation damage. The role of Na2SO4 as a charge compensator has been studied in detail. An attempt has been made to unravel the type of kinetics involved in
the process, by calculating the activation energies by different methods. It has been concluded that the type of kinetics
involved in the process is bimolecular. 相似文献
944.
A conformally flat accelerated charge metric is found in an arbitrary dimension D. It is a solution of the Einstein-Maxwell-null fluid equations with a cosmological constant in D ≥ 4 dimensions. When the acceleration is zero, our solution reduces to the Levi-Civita-Bertotti-Robinson metric. We show
that the charge loses its energy, for all dimensions, due to the acceleration. 相似文献
945.
I. Haysak Yu. Fekete V. Morokhovych S. Chalupka M. Salak 《Czechoslovak Journal of Physics》2005,55(5):541-554
Based on the numeric solution of a system of coupled channels for vector mesons (S-and D-waves mixing)and for tensor mesons (P- and F- waves mixing) mass spectrum and wave functions of a family of vector mesons q
in triplet states a e obtained. The calculations are performed using a well-known Cornell potential with a mixed Lorentz- structure of the confinement term. The spin-dependent part of the potential is taken from the Breit-Fermi approach.The effect of irregular terms of the potential is considered within the framework of the perturbation theory and/or of the configuration interaction approach, modified for a system of coupled equations. It is shown that even a small integral contribution of the D-wave to the total wave function of q
system is very impotant for the calculation of certain characteristics of the meson states. 相似文献
946.
947.
948.
Emmanuel Chetcuti Anatolij Dvurečenskij 《International Journal of Theoretical Physics》2004,43(2):369-384
Let S be an inner product space and let E(S) (resp. F(S)) be the orthocomplemented poset of all splitting (resp. orthogonally closed) subspaces of S. In this article we study the possible states/charges that E(S) can admit. We first prove that when S is an incomplete inner product space such that dim S/S < , then E(S) admits at least one state with a finite range. This is very much in contrast to states on F(S). We then go on showing that two-valued states can exist on E(S) not only in the case when E(S) consists of the complete/cocomplete subspaces of S. Finally we show that the well known result which states that every regular state on L(H) is necessarily -additive cannot be directly generalized for charges and we conclude by giving a sufficient condition for a regular charge on L(H) to be -additive. 相似文献
949.
Results on the paper's theme are reviewed. Attention is focused mainly on the use of transients of current and open-circuit potential for elucidating changes in the structure of the electrical double layer (EDL) caused by the CO adsorption. It is shown that the high binding energy of CO with surfaces of platinum metals leads to a strong suppression of the total differential capacitance of the electrode, the recharge of the surface, the displacement of strongly adsorbed atoms formed during the adsorption of ions with a total charge transfer, and to other alterations in the EDL plates facing both solution and metal. The importance of allowing for double-layer effects when solving problems of electrocatalysis on platinum metals is emphasized. 相似文献
950.