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Shaaban, I. A., T. A. Mohamed, W. M. Zoghaib, L. D. Wilson, R. S. Farag, M. S. Afifi, and Y. A. Badr, "Tautomerism, Raman, infrared and ultraviolet-visible spectra, vibrational assignments, MP2 and B3LYP calculations of dienol 3,4-dihydroxypyridine, keto-enol 3-hydroxypyridin-4-one and keto-enol dimer", Journal of Molecular Structure, vol. 1043, pp. 52-67, 2013. AbstractWebsite
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Kassem, M. A., and R. M. Khafagy, "Thermal stability, crystallization kinetics and mechanical properties of Al81.8Ni9.2Co4.8Y3.1Zr1.1 amorphous alloy consolidated to a fully dense nanocrystalline matrix with some remaining amorphous phase", Journal of Alloys and Compounds, vol. 607, pp. 291 - 299, 2014. AbstractWebsite

Abstract High-strength nanocrystalline-embedded-alloy was successfully fabricated by the consolidation of melt-spun amorphous ribbons of Al81.8Ni9.2Co4.8Y3.1Zr1.1. The as-melt amorphous spun, the annealed and the fully dense nanocrystalline extruded specimens were investigated using XRD, HRTEM, SAED, \{EDX\} line mapping, microhardness, compression tests, \{SEM\} at fractured surfaces and the crystallization’s kinetics were determined from DSC. XRD, in good accordance with HRTEM, \{SAED\} and the associated \{EDX\} line mapping analysis, revealed the merely amorphous nature of the as-melt spun ribbons and confirmed bearing of nanocrystalline-embedded phases in the annealed and extruded specimens with the remaining of some amorphous phase. \{HRTEM\} and \{SAED\} revealed that annealing at 275 °C resulted in the formation of short-range ordered regions of fcc α-Al nanoparticles and intermetallic nanocrystalline-embedded grains of 5–10 nm that grown to 20–50 nm after extrusion. \{DSC\} showed that the as-melt spun ribbons crystallize at three stages in contrast to one late stage shown by the extruded sample. Crystallization kinetics of the as-spun ribbons yielded crystallization activation energy (Ec) of 143.4 and 36 kJ/mol for the first and second crystallization peaks respectively. The extruded specimen showed improved strength of 550 at a load of 50 g while the as-melt spun ribbons indicated lower hardness of 367 at a similar load. The ultimate compressive stress of the extruded specimen reached 800 MPa with 0.66% strain and Young’s modulus of 1.26 GPa. \{SEM\} micrographs of the fracture surface showed a transgranular failure with a dimpled surface reflecting the microplasticity of the final product. Improved mechanical properties and thermal stability of the nanocrystalline-embedded-specimen are due to the nanoparticle strengthening effect of the very hard and non-deformable nanosized α-aluminum and Al-based intermetallic nanograins that are densely formed during the annealing, extrusion and nano-indentation processes.

Kassem, M. A., and R. M. Khafagy, "Thermal stability, crystallization kinetics and mechanical properties of Al81.8Ni9.2Co4.8Y3.1Zr1.1 amorphous alloy consolidated to a fully dense nanocrystalline matrix with some remaining amorphous phase", Journal of Alloys and Compounds, vol. 607, pp. 291 - 299, 2014. AbstractWebsite

Abstract High-strength nanocrystalline-embedded-alloy was successfully fabricated by the consolidation of melt-spun amorphous ribbons of Al81.8Ni9.2Co4.8Y3.1Zr1.1. The as-melt amorphous spun, the annealed and the fully dense nanocrystalline extruded specimens were investigated using XRD, HRTEM, SAED, \{EDX\} line mapping, microhardness, compression tests, \{SEM\} at fractured surfaces and the crystallization’s kinetics were determined from DSC. XRD, in good accordance with HRTEM, \{SAED\} and the associated \{EDX\} line mapping analysis, revealed the merely amorphous nature of the as-melt spun ribbons and confirmed bearing of nanocrystalline-embedded phases in the annealed and extruded specimens with the remaining of some amorphous phase. \{HRTEM\} and \{SAED\} revealed that annealing at 275 °C resulted in the formation of short-range ordered regions of fcc α-Al nanoparticles and intermetallic nanocrystalline-embedded grains of 5–10 nm that grown to 20–50 nm after extrusion. \{DSC\} showed that the as-melt spun ribbons crystallize at three stages in contrast to one late stage shown by the extruded sample. Crystallization kinetics of the as-spun ribbons yielded crystallization activation energy (Ec) of 143.4 and 36 kJ/mol for the first and second crystallization peaks respectively. The extruded specimen showed improved strength of 550 at a load of 50 g while the as-melt spun ribbons indicated lower hardness of 367 at a similar load. The ultimate compressive stress of the extruded specimen reached 800 MPa with 0.66% strain and Young’s modulus of 1.26 GPa. \{SEM\} micrographs of the fracture surface showed a transgranular failure with a dimpled surface reflecting the microplasticity of the final product. Improved mechanical properties and thermal stability of the nanocrystalline-embedded-specimen are due to the nanoparticle strengthening effect of the very hard and non-deformable nanosized α-aluminum and Al-based intermetallic nanograins that are densely formed during the annealing, extrusion and nano-indentation processes.

Afifi, G., M. A. Khedr, Y. Badr, M. Danailov, P. Sigalotti, P. Cinquegrana, M. B. Alsous, and A. R. Galaly, "Timing stability enhancement of an Erbium Doped mode locked Fiber Laser using SESAM mirror", Optical Fiber Technology, vol. 29, pp. 74-83, 2016. AbstractWebsite
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Ouni, S., M. M. Cohen, and D. W. Massaro, "Training Baldi to be multilingual: A case study for an Arabic Badr", Speech Communication, vol. 45, no. 2, pp. 115 - 137, 2005. AbstractWebsite

In this paper, we describe research to extend the capability of an existing talking head, Baldi, to be multilingual. We use parsimonious client/server architecture to impose autonomy in the functioning of an auditory speech module and a visual speech synthesis module. This scheme enables the implementation and the joint application of text-to-speech synthesis and facial animation in many languages simultaneously. Additional languages can be added to the system by defining a unique phoneme set and unique phoneme definitions for the visible speech for each language. The accuracy of these definitions is tested in perceptual experiments in which human observers identify auditory speech in noise presented alone or paired with the synthetic versus a comparable natural face. We illustrate the development of an Arabic talking head, Badr, and demonstrate how the empirical evaluation enabled the improvement of the visible speech synthesis from one version to another.

Kamel, R., E. Najeeb, Y. A. Badr, M. A. Semary, and M. A. Hadhoud, "TWO-STAGE STRESS-DEPENDENT CREEP MECHANISM IN PLASTICIZED POLY(VINYL CHLORIDE) (PVC).", Journal of polymer science. Part A-1, Polymer chemistry, vol. 17, no. 12, pp. 4003-4010, 1979. AbstractWebsite
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