فهرست مطالب

  • Volume:35 Issue:3, 2011
  • A3
  • تاریخ انتشار: 1390/08/25
  • تعداد عناوین: 10
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  • R. Kh. Amirov, N. Durna, M. Yildirim Page 175
    There are many different ways to subdivide the spectrum of a bounded linear operator; some of them are motivated by applications to physics (in particular, quantum mechanics). In this study, the relationship between the subdivisions of spectrum which are not required to be disjoint and Goldberg's classification are given. Moreover, these subdivisions for some summability methods are studied.
  • M. Kazemi, G. H. Erjaee Page 185
    In this article, we study the analytical solutions of different parabolic heat equations with different boundary conditions in the form of multi-term fractional differential equations. Then we compare these analytical solutions with numerical finite difference methods. This comparison demonstrates the accuracy of the analytical and numerical methods presented here.
  • A. Maher, Ye. A. Utkina Page 193
    In this paper, the Goursat problem of a general form for a linear partial differential equation is investigated with the help of the Riemann function method. Some results are given concerning the existence and uniqueness for the solution of the suggested problem.
  • N. Ghahramany, Sh. Gharaati, M. Ghanaatian, H. Hora Page 201
    Following our previous presentation of a new three-fold symmetry for derivation of the magic numbers of nuclei based upon a quark state model of nuclei, here the nuclear binding energy is obtained from such new perspective. From this point of view, since each nucleon is made of three quarks, the binding energy of nuclei contains a volume term proportional to 3A (A is mass number). By considering the asymmetry in the number of up and down quarks and also coulomb correction, a new formula is presented that calculates the nuclear binding energy in terms of only $ and Z numbers for most of the stable nuclides. PACS: 21.10.Dr, 21.90.+90, 21.10.-K, 12.38.Mh, 12.90.+b
  • M. Abbas, S. H. Khan Page 209
    A definition of two jointly asymptotically nonexpansive mappings S and T on uniformly convex Banach space E is studied to approximate common fixed points of two such mappings through weak and strong convergence of an Ishikawa type iteration scheme generated by S and T on a bounded closed and convex subset of E. As a consequence of the notion of two jointly asymptotically nonexpansive maps, we can relax the very commonly used strong condition “F(S) and F(T) has a nonempty intersection” with the weaker assumption “either F(S) is nonempty or F(T) is nonempty”. Our convergence results are refinements and generalizations of several recent results from the current literature.
  • A. Keshavarz, M. M. Golshan Page 217
    In this work we investigate the thermal entanglement between two-level atoms and photons in a nonlinear cavity.We consider intensity-dependent couplings and calculate the negativity, as a measure of atom-photon entanglement. The cavity is assumed to be at a temperature T, so that all number of photons, and at the same time, both atomic states, with definite probabilities, are present. We then demonstrate a condition under which the intensity-dependent coupling leads to entanglement. It is also shown that, as in the case of linear Jaynes- Cummings model, the thermal states of atoms and photons are never separable.
  • H. Rahimi Page 223
  • M. Nokhbatolfoghahai, P. Tsimbouri, J. B. Wilson, J. R. Downie Page 229
    The cement gland (CG) is a transient organ, found in most anuran embryos and early larvae and located normally on the front of the head. Its sticky secretion allows newly hatched larvae to attach to the egg jelly or to another support later and remain hidden and stationary until feeding starts. Our ultrastructural studies showed that prominence structure of the CG in some species exists, but is lacking in some others. Previous work has shown that a large number of genes have a role in CG development in Xenopus laevis. The aim of the present study is to find out whether the loss of cement gland formation for those species studied here occurs because of missing genes or for other reasons. In order to test whether some of these genes are present in other anuran species, especially in those where the CG does not form, genomic DNAs were examined for sequence similarity by low stringency hybridization. Sequences from three different genes with a role in controlling CG development in Xenopus (otx-2, xcg-1 and xag-1) were individually hybridised with genomic DNA of four species of anurans (X. laevies, Leptodactylus fuscus, Phyllomedusa trinitatis and Physalaemus pustulosus) and one species of rodent (Muss musculus domesticus strain C57Bl/ 6). The results showed that Xenopus probes can detect the presence of potential homologues of all three genes in the different species. For the two genes most specifically involved in CG development, xcg-1 and xag-1, both are clearly present, even in the two species which lack CG development, though in one of these, P. trinitatis, xag-1 shows considerable difference from the other species. At this stage, we can conclude that the missing cement gland for those species studied here is not due to a lack of the genes responsible for the gland development. In order to carry this work further, in situ hybridisation should be used to determine the actual expression patterns of these genes.
  • M. Zarei, A. Jarrahpour Page 235
    Pure azo Schiff bases were readily and conveniently accessible in high yields by mixing of the reagents either as aqueous slurry, or by grinding at room temperature. This method, unlike a classical method, needs neither harsh conditions nor organic solvents. The satisfactory results were obtained with excellent yields, short reaction time, and operational simplicity in the experimental procedure. Comparison of time and yield in this green method with the classical methods is also performed.
  • M. B. Faghir, F. Attar, B. Ertter Page 243