Hosam Gomaa - Academia.edu (original) (raw)
Papers by Hosam Gomaa
Radiation Physics and Chemistry
Optical and Quantum Electronics
Journal of Inorganic and Organometallic Polymers and Materials
Journal of Computational Electronics
Polymers and Polymer Composites
Samples of pure poly(methyl methacrylate) (PMMA) and PMMA enhanced with metal complexes of Zn, Cd... more Samples of pure poly(methyl methacrylate) (PMMA) and PMMA enhanced with metal complexes of Zn, Cd, and Hg were synthesized via catalytic chain transfer polymerization. Structural analysis, by means of XRD, showed the amorphous nature of the studied samples which meant high homogenous dissolution of the metals (Zn, Cd and Hg) into the polymer matrix. Density values increased linearly with respect to atomic radius of the incorporated metals. Addition of such elements causes an increase in mass attenuation coefficients and a remarkable decrease in the Half Value Layer (HVL) values, in comparison to existing standard shielding materials. Thermal studies by DSC indicated highly homogenous internal structure of the studied samples, with slight decrease in the Tg value when introducing metals due to heterogeneous nucleation agent role of the Cd, Zn and Hg. All observations and results suggest the studied materials to be used as promising and proper aprons for medical radiation shielding ap...
Applied Physics A, 2020
Some bismuth borate glasses containing an equal concentration of both ZnO and CaO were prepared u... more Some bismuth borate glasses containing an equal concentration of both ZnO and CaO were prepared using the fast cooling method, in the air. X-ray diffraction and Fourier transform infrared techniques were used to characterize these glasses. All samples showed amorphous natures, with short-range order networks. Introducing of both ZnO and CaO caused BO 4 groups to convert to BO 3 with an observable decreasing in the molar volume. Linear refractive index decreased with increasing the wavelength of the incident light, while the nonlinear refractive index increased. Linear and nonlinear susceptibilities decreased with introducing ZnO and CaO.
Journal of Non-Crystalline Solids, 2018
Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional mel... more Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional melting quenching technique, all mixtures are in an agreement with the following chemical formula (25-x) mol% Na 2 O. x mol% NaCl.15 mol% FeO. 30 mol% B 2 O 3. 30 mole% P 2 O 5 , where x = 0.0, 05, 10, 15, 20 and 25. Sample of x= 0, only, has been exposed to different doses of gamma rays (0.0, 05, 10 and 20 kGy). Mossbauer Effect ME spectroscopy have been carried out at RT for all irradiated {x =0.0} and for non-irradiated {x> 0.0} samples. ME parameters showed all samples in good glassy state. Also ME parameters showed the iron ions in two different coordination states, where all Fe 2+ ions and some of Fe 3+ ions shared the octahedral coordination states, while the tetrahedral coordination states occupied only by Fe 3+ ions. It was observed that both the gamma irradiation process and the process of replacement Na 2 O by NaCl caused the Fe 2+ ions to oxidize to Fe 3+ ions.
American Journal of Materials Synthesis and Processing, 2017
This paper is a simple idea aims to how to get an imagination about the variation of glass refrac... more This paper is a simple idea aims to how to get an imagination about the variation of glass refractive index with its internal structure. In the present work an empirical equation for the refractive index of a glass sample has been achieved as function of both the glass molar Volume and the glass electronegativity. Like this equation, may be used to determine and estimate the refractive index value of an inorganic oxide glass sample, if its density measured with high accuracy.
Journal of Electronic Materials
Optics & Laser Technology
Journal of Computational Electronics
Journal of the Australian Ceramic Society
Journal of Materials Science: Materials in Electronics
Journal of Materials Science: Materials in Electronics
Sodium borate glass doped with cerium oxide, 0–10 wt%, has been prepared based on the quenching m... more Sodium borate glass doped with cerium oxide, 0–10 wt%, has been prepared based on the quenching method from the melting point. The XRD, DSC, FTIR, and UV–Vis are used to study the structure, thermal, optical properties and shielding attenuation of the studied materials. XRD analysis showed that the as-prepared samples are amorphous in nature. Increased CeO2 content in the glassy matrix led to an increase in the glass stability, the dielectric constant value, as well as the optical transparency. The measured shielding parameters of the present study revealed that the glass system containing 10 wt% of CeO2 exhibits the better photon shielding performance than the glass of 0 wt% CeO2. Cerium-rich glass showed the highest resistance for both gamma-ray and the fast neutrons among all the present samples. The removal cross-sections varied from between 89 × 10–3 cm−1, for the cerium-free sample, and 97 × 10–3 cm−1 for cerium-rich sample. Such observation may nominated Ce-rich glass to be used in some shielding and attenuation applications, especially for gamma-ray and fast neutrons applications.
Oxide glasses doped with transition metal ions are of high interest because of their variant appl... more Oxide glasses doped with transition metal ions are of high interest because of their variant applications in both science and technology fields. However, the normal melt quench method have used to prepared some iron doped phosphate glasses according the following molecular formula: (65-x) mol% P2O5 20 mol% Na2O 15 mol% Fe2O3 x mol% MnO, Where x= 0, 5,10, 20, 25. The room temperature Mössbauer Effect ME Spectra used to characterized the glassy state homogeneity of these glasses. ME spectra show, for all glasses, no magnetic field participate which mean good glassy state formation. The ac electrical transport properties were also measured, as function of temperature up to 500k. It was found that the ac conductivity increased with the gradual increase of Mn2+ cations, while the electrical activation energy decreased.
Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional mel... more Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional melting quenching technique, all mixtures are in an agreement with the following chemical formula (25-x) mol% Na2O. x mol% NaCl.15 mol% FeO. 30 mol% B2O3. 30 mole% P2O5, where x = 0.0, 05, 10, 15, 20 and 25. Sample of x= 0, only, has been exposed to different doses of gamma rays (0.0, 05, 10 and 20 kGy). Mossbauer Effect ME spectroscopy have been carried out at RT for all irradiated {x =0.0} and for non-irradiated {x> 0.0} samples. ME parameters showed all samples in good glassy state. Also ME parameters showed the iron ions in two different coordination states, where all Fe2+ ions and some of Fe3+ ions shared the octahedral coordination states, while the tetrahedral coordination states occupied only by Fe3+ ions. It was observed that both the gamma irradiation process and the process of replacement Na2O by NaCl caused the Fe2+ ions to oxidize to Fe3+ ions.
Radiation Physics and Chemistry
Optical and Quantum Electronics
Journal of Inorganic and Organometallic Polymers and Materials
Journal of Computational Electronics
Polymers and Polymer Composites
Samples of pure poly(methyl methacrylate) (PMMA) and PMMA enhanced with metal complexes of Zn, Cd... more Samples of pure poly(methyl methacrylate) (PMMA) and PMMA enhanced with metal complexes of Zn, Cd, and Hg were synthesized via catalytic chain transfer polymerization. Structural analysis, by means of XRD, showed the amorphous nature of the studied samples which meant high homogenous dissolution of the metals (Zn, Cd and Hg) into the polymer matrix. Density values increased linearly with respect to atomic radius of the incorporated metals. Addition of such elements causes an increase in mass attenuation coefficients and a remarkable decrease in the Half Value Layer (HVL) values, in comparison to existing standard shielding materials. Thermal studies by DSC indicated highly homogenous internal structure of the studied samples, with slight decrease in the Tg value when introducing metals due to heterogeneous nucleation agent role of the Cd, Zn and Hg. All observations and results suggest the studied materials to be used as promising and proper aprons for medical radiation shielding ap...
Applied Physics A, 2020
Some bismuth borate glasses containing an equal concentration of both ZnO and CaO were prepared u... more Some bismuth borate glasses containing an equal concentration of both ZnO and CaO were prepared using the fast cooling method, in the air. X-ray diffraction and Fourier transform infrared techniques were used to characterize these glasses. All samples showed amorphous natures, with short-range order networks. Introducing of both ZnO and CaO caused BO 4 groups to convert to BO 3 with an observable decreasing in the molar volume. Linear refractive index decreased with increasing the wavelength of the incident light, while the nonlinear refractive index increased. Linear and nonlinear susceptibilities decreased with introducing ZnO and CaO.
Journal of Non-Crystalline Solids, 2018
Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional mel... more Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional melting quenching technique, all mixtures are in an agreement with the following chemical formula (25-x) mol% Na 2 O. x mol% NaCl.15 mol% FeO. 30 mol% B 2 O 3. 30 mole% P 2 O 5 , where x = 0.0, 05, 10, 15, 20 and 25. Sample of x= 0, only, has been exposed to different doses of gamma rays (0.0, 05, 10 and 20 kGy). Mossbauer Effect ME spectroscopy have been carried out at RT for all irradiated {x =0.0} and for non-irradiated {x> 0.0} samples. ME parameters showed all samples in good glassy state. Also ME parameters showed the iron ions in two different coordination states, where all Fe 2+ ions and some of Fe 3+ ions shared the octahedral coordination states, while the tetrahedral coordination states occupied only by Fe 3+ ions. It was observed that both the gamma irradiation process and the process of replacement Na 2 O by NaCl caused the Fe 2+ ions to oxidize to Fe 3+ ions.
American Journal of Materials Synthesis and Processing, 2017
This paper is a simple idea aims to how to get an imagination about the variation of glass refrac... more This paper is a simple idea aims to how to get an imagination about the variation of glass refractive index with its internal structure. In the present work an empirical equation for the refractive index of a glass sample has been achieved as function of both the glass molar Volume and the glass electronegativity. Like this equation, may be used to determine and estimate the refractive index value of an inorganic oxide glass sample, if its density measured with high accuracy.
Journal of Electronic Materials
Optics & Laser Technology
Journal of Computational Electronics
Journal of the Australian Ceramic Society
Journal of Materials Science: Materials in Electronics
Journal of Materials Science: Materials in Electronics
Sodium borate glass doped with cerium oxide, 0–10 wt%, has been prepared based on the quenching m... more Sodium borate glass doped with cerium oxide, 0–10 wt%, has been prepared based on the quenching method from the melting point. The XRD, DSC, FTIR, and UV–Vis are used to study the structure, thermal, optical properties and shielding attenuation of the studied materials. XRD analysis showed that the as-prepared samples are amorphous in nature. Increased CeO2 content in the glassy matrix led to an increase in the glass stability, the dielectric constant value, as well as the optical transparency. The measured shielding parameters of the present study revealed that the glass system containing 10 wt% of CeO2 exhibits the better photon shielding performance than the glass of 0 wt% CeO2. Cerium-rich glass showed the highest resistance for both gamma-ray and the fast neutrons among all the present samples. The removal cross-sections varied from between 89 × 10–3 cm−1, for the cerium-free sample, and 97 × 10–3 cm−1 for cerium-rich sample. Such observation may nominated Ce-rich glass to be used in some shielding and attenuation applications, especially for gamma-ray and fast neutrons applications.
Oxide glasses doped with transition metal ions are of high interest because of their variant appl... more Oxide glasses doped with transition metal ions are of high interest because of their variant applications in both science and technology fields. However, the normal melt quench method have used to prepared some iron doped phosphate glasses according the following molecular formula: (65-x) mol% P2O5 20 mol% Na2O 15 mol% Fe2O3 x mol% MnO, Where x= 0, 5,10, 20, 25. The room temperature Mössbauer Effect ME Spectra used to characterized the glassy state homogeneity of these glasses. ME spectra show, for all glasses, no magnetic field participate which mean good glassy state formation. The ac electrical transport properties were also measured, as function of temperature up to 500k. It was found that the ac conductivity increased with the gradual increase of Mn2+ cations, while the electrical activation energy decreased.
Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional mel... more Boro-phosphate oxide glass system doped with iron ions have been prepared by the conventional melting quenching technique, all mixtures are in an agreement with the following chemical formula (25-x) mol% Na2O. x mol% NaCl.15 mol% FeO. 30 mol% B2O3. 30 mole% P2O5, where x = 0.0, 05, 10, 15, 20 and 25. Sample of x= 0, only, has been exposed to different doses of gamma rays (0.0, 05, 10 and 20 kGy). Mossbauer Effect ME spectroscopy have been carried out at RT for all irradiated {x =0.0} and for non-irradiated {x> 0.0} samples. ME parameters showed all samples in good glassy state. Also ME parameters showed the iron ions in two different coordination states, where all Fe2+ ions and some of Fe3+ ions shared the octahedral coordination states, while the tetrahedral coordination states occupied only by Fe3+ ions. It was observed that both the gamma irradiation process and the process of replacement Na2O by NaCl caused the Fe2+ ions to oxidize to Fe3+ ions.