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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
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.

A.Aziz, R. O., Optimization of Material Test Research Reactors for Isotope Production, , Giza, Cairo university, 2015.
Aziz, R. O. A. A., OPTIMIZATION of MTR reactor core fuel loading for isotope production, , Cairo- Giza, Cairo University, 2014.
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%.

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