Browsing by Author "El-Alaily N.A."

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Effect of concentrations and irradiation on the etching of soda-lime-silica glass
(2011) El-Alaily N.A.; Mahmoud H.H.; Abd-elaziz T.D.; Ezz-eldin F.M.; National Center for Radiation Research and Technology; P.O.BOX: 29; Nasr-City; Cairo; Egypt; MSA University (October University for Modern Sciences and Arts); 6th October City; Egypt
We present the results of experiments of etching on commercial soda-lime-silicate glasses (SLS) immersed in dilute hydrofluoric acid solutions. The effect of different parameters (such as concentration, immersion time, temperature and irradiation) on the etching of silica has been investigated and expressed by the loss in gm/cm2. It has been found that the dissolution of glass increases with increasing both immersion time and HF concentration. The results show that the sodium concentration increases in the leachant solution as the concentration of HF increases. UV-VIS measurements of the leachate show strong UV absorption which is attributed to the presence of silica released from the corroded glass. Morphological and chemical composition changes were followed using scanning electron microscopy (SEM) combined with energy dispersive x-ray (EDX). The results indicate the formation of crust layers. The ionization of the glass during the passage of gamma-rays results in substantial changes to the chemical reactivity of the glass surface.The results showed an increase in the quantity of corrosion which indicates that irradiation might enhance the corrosion reaction mechanism and consequently the surface corrosion products. FTIR spectroscopy was performed for physico-chemical characterizations. In addition to the silanol band at ~3720 cm-1, IR features are attributed to free hydrogen-bonded and structurally bound molecular water and to silanol which is hydrogen-bonded to neighboring groups. The existence of these species and their behavior during etching are related to a specific mechanism for the reaction between silica glass and molecular water.
Effect of gamma radiation on some optical and electrical properties of lithium bismuth silicate glasses
(Springer New York LLC, 2019) Abou Hussein E.M.; Abd Elaziz T.D.; El-Alaily N.A.; Radiation Chemistry Department; National Center for Radiation Research and Technology; Atomic Energy Authority; P. O. Box 8029; Nasr City; Cairo 11371; Egypt; Chemistry Department; Foundation Academy for Sciences and Technology (FAST); Batterjee Medical College (BMC); Jeddah; Saudi Arabia; October University for Modern Sciences and Arts (MSA); 6th of October City; Egypt
Lithium bismuth silicate glasses with the composition of; 68% SiO2, 20% Bi2O3, 8% Li2O3, 4% Na2O doped with either 2% PbO, BaO or SrO (all in wt%) were studied to investigate some of their optical and electrical properties before and after different doses of gamma radiation. Density, oxygen packing density OPD, molar and specific volumes, optical UV absorption, optical energy gap, electrical conductivity and dielectric measurements were measured and discussed in this study regarding the effect of gamma radiation. The results showed that all glasses were more affected at the higher radiation dose (100�kGy) than the lower radiation dose (50�kGy) because of the creation of more defects and non- bridging oxygens NBOs at the higher dose. In spite of that, Pb2+ ions containing glass revealed better properties to resist gamma radiation than glasses containing either Ba2+ or Sr2+ ions because of its highly compacted structure and the low concentration of NBOs, defects or vacancies as well as the high polarizability of Pb2+ ions that plays an effective role in enhancing the glass optical and electrical properties. � 2019, Springer Science+Business Media, LLC, part of Springer Nature.
Effect of Iron Slag on the Corrosion Resistance of Soda Lime Silicate Glass
(Springer Netherlands, 2018) El-Alaily N.A.; Abd-Elaziz T.D.; Soliman L.; National Center for Radiation Research and Technology; Nasr City; Cairo; Egypt; October University for Modern Sciences and Arts (MSA); 6th October City; Cairo; Egypt
Soda lime silicate glasses containing different amounts of iron slag 30 % were prepared. The chemical durability of the prepared glasses was examined by immersion in HCl or HNO3 solutions at room temperature. The results show that the glass durability increases with increasing the amount of slag in the glass composition to a certain amount, then followed by a decrease in the glass durability. Various mechanisms of corrosion and the role of the mobility of cations and their leaching into solution, also the effect of time of leaching are discussed. The densities of all glass compositions were measured. The quantitative analysis obtained from infrared absorption spectra in the range of (400 4000) cm?1 in relation to the effect of corrosion on the absorption spectra has been studied in terms of structural concepts. The topography of the glass surfaces was observed by scanning electron microscopy (SEM). The concentration percentage of the ions present on the glass surface was determined by Energy Dispersive X-ray analysis (EDX). 2015, Springer Science+Business Media Dordrecht.
Vitrified municipal waste as a host form for high-level nuclear waste
(2014) El-Alaily N.A.; Abou-Hussein E.M.; Abdel-Monem Y.K.; Abd Elaziz T.D.; Ezz-Eldin F.M.; National Center for Radiation Research and Technology; P.O. Box 29; Nasr City; Cairo 11765; Egypt; Faculty of Science; El-Mounofia University; El-Mounofia; Egypt; October University for Modern Sciences and Arts (MSA); 6th October City; Egypt
Preparing glass to be used as a radioactive waste immobilizer from municipal waste is the aim of this paper. Up to 90 wt% of municipal waste was obtained by burning the raw waste at 700 C for 5 h; this were successfully vitrified into borosilicate and sodium borate glasses at ~1,200 C. The long term behavior of such glass is one of the most important factors, which is determined by their durability in aqueous solution. Experimental durability data of the prepared glass immersed in ground water together with ?-irradiation was found to be affected according to the different irradiation doses. In addition, thermal analysis and glass surface morphology were investigated. The evolution of the damage on the studied properties was correlated to the changes in the glass network depending on their composition and irradiation dose. The results showed that glass matrix containing higher amount of municipal waste possess high durability and low thermal expansion after being gamma irradiated. The results showed that glass containing higher amount of municipal waste possess high durability and low thermal expansion after irradiation. 2013 Akad miai Kiad, Budapest, Hungary.