Publications

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Journal Article
Hamadiche, M., and H. Abou-Shady, "Optical fiber instability during coating process", Journal of Fluids and Structures, vol. 22, issue 5, pp. 599 - 615, 2006. AbstractWebsite

In the present work, we study the stability of a system designed for the coating of optical fiber. This is achieved by studying the stability of the flowing resin in the die while coupled with a viscoelastic optical fiber. We develop a numerical code based on a sixth-order compact finite-difference method in order to solve the two-dimensional Navier–Stokes equations. We show that there is a bifurcation flow for a given value of the Reynolds number, wherever the vibration of the optical fiber has been experimentally observed. The stability of the resulting flow, coupled with a nonrigid optical fiber, is considered. Two-dimensional and three-dimensional stability analyses were made. The system was found to be subjected to two kinds of instability induced by two distinguishable groups of modes. For an optical fiber with a small radius, we assume that the preceding vibration may not be the only cause of the irregularity in the coating thickness. Therefore, a model taking into account the deformation of the liquid resin surface, under the action of the surface-tension forces, before resin solidification, and after leaving the die, is proposed. This model assumes that the liquid layer is subjected to surface-tension and gravity forces. It was found that the dynamic equation depends on two dimensionless parameters. It is found that the surface of the fiber has a wavy form. The length of the wave depends on the two dimensionless parameters. Our work shows qualitative agreement with the experimental results without adjusting arbitrary constants.

Guirgis, O. W., S. A. Elawam, W. M. Morsi, and H. A. M. Shady, "Optical properties study of PMMA/PbO(NP's) composites films", Materials science, vol. 14, issue 12, pp. 471-483, 2016. optical_prop.pdf
Ismail, M., M. M. Osman, E. H. Gebaly, and H. Abou-Shady, "Orientation and deformation dependence of the reaction cross-section for a deformed target nucleus", Modern Physics Letters A, vol. 18, issue 1, pp. 57-64, 2003. AbstractWebsite

The optical limit approximation to Glauber theory was used to calculate the reaction cross-section, σR, for a deformed target nucleus. A method is presented to include both density dependence of NN reaction cross-section and higher order deformations of the target nucleus. We studied orientation, energy and deformation dependence of σR for C12–N17 and C12–U238 interacting pairs. We found that the orientation dependence of σR for the heavy target U238 depends on the value and sign of hexadecapole deformation and it is more than 2.2 times compared to the light deformed target nucleus N17. The presence of hexadecapole deformation does not affect the value of σR averaged over all orientation of the target nucleus. A geometrical model was proposed to account for the orientation dependence of σR. We found that the error in this model is less than 10%.

Elawam, S. A., O. W. Guirguis, W. M. Morsi, and H. M. Abou-Shady, "Structural Configuration and Thermal Analyses of Composite Films of Poly (methyl methacrylate)/Lead Oxide Nanoparticles", SSRG International Journal of Applied Physics (SSRG-IJAP), vol. 3, issue 6, pp. 1- 8, 2016.
Ismail, M., W. M. Seif, A. Bakry, and H. Abou-Shady, "Study of Coulomb interaction for two diffuse spherical-deformed nuclei", Physics of Atomic Nuclei, vol. 69, issue 9, pp. 1463-1471, 2006. AbstractWebsite

The Coulomb interaction for a spherical—deformed interacting pair is derived assuming realistic nuclear charge distributions. The effect of a finite diffuseness parameter is described either by the folding product of spherical or deformed sharp-surface distribution and a spherical short-range function or by using a Fermi two-parameter distribution function. The approximate solutions obtained using these categories of charge distributions are then compared to the numerical solution obtained within the framework of the double-folding model. We found that the finite surface diffuseness parameter affects slightly the inner region of the total Coulomb potential, while it produces large errors in calculating the Coulomb form factors used frequently in nuclear reactions and fusion numerical codes.

Conference Proceedings
Ismail, M., A. Y. Ellithi, and H. Abou-Shady, "EFFECT OF ISO-SPIN AVERAGING AND FINITE RANGE OF THE NN FORCE ON REACTION CROSS SECTION FOR NEUTRON RICH NUCLEI", A new era of nuclear structure physics. Proceedings of the international symposium (NENS03): IAEA - world scientific, pp. 330-331, 2004. Abstract

The optical limit to Glauber theory is used to calculate the reaction cross section, σR, for neutron rich nuclei. In-medium and iso-spin dependence of the effective nucleon-nucleon (NN) reaction cross-section, σNN, are treated correctly assuming both finite and zero range NN interaction. We find that the combined effect of iso-spin dependence and finite range of NN force can increase up to 20% for neutron rich nuclei compared to σR calculated using zero range approximation and constant matter density value 0.16 fm-3 in σNN. The maximum percentage increase is reduced to 13% compared with σR based on free NN cross section

ALAZIZ, A. B. D. R. O., A. A. ESMAT, and H. Abou-Shady, "OPTIMIZATION OF MATERIAL TEST RESEARCH REACTOR CORE FOR ISOTOPE PRODUCTION", Research Reactors: Safe Management and Effective Utilization, Morocco, iaea, pp. 1-3, 2011. Abstract

In this paper Neutronic calculation (deterministic approach) has been carried out to characterize the neutron flux in
locations used for isotope production to achieve optimum utilization of the reactor. In neutronic calculations a number of
approximations take place. As a result even if one uses the same codes the results might be different. It is thus of importance
to care about the model used. Comparison between different model and with published experimental results has been done. In
this work three deferent model of the standard fuel has been tested to determine the accurate one, then it used for core
calculation. Calculation of reactivities at deferent cycles, calculation of power densities, neutron flux, and burn-up as well as
search for equilibrium were performed to determine the equilibrium core. Standard computer codes WIMSD-5B and
CITVAP were used.

Book Chapter
Abou-Shady, H., "ما الكون", ما الكون, القاهرة, المجلس الاعلي للثقافة, 2006.