Manuscript Information Authors

[1]	Abdullah Mohammad Shehada, Department of Physics, Damascus University, Damascus, Syria.
[2]	Mohammad Hassan Kharita, Department of Protection and Safety, Atomic Energy Commission of Syria, Damascus, Syria.
[3]	Serag Yousef, Department of Engineering Technical Services, Atomic Energy Commission of Syria, Damascus, Syria.

Abstract

The purpose of the research in this paper is to produce a radiation shielding glass by recycling glass of cathode ray tubes (CRTs) which come from used computers and TV sets and adding some heavy metal oxides as lead oxide (PbO) to increase the density, and using some other oxides such as potassium oxide (K₂O) as a modifier for the resulted glasses. Because of, the glass of cathode ray tubes (CRTs) contains some heavy oxides. Where the part Funnel contains about 20% of lead oxide (PbO) while the part Panel contains about 10% of barium oxide (BaO) and the same percent for strontium oxide (SrO). So these glasses can be used as a radiation shielding glass for nuclear and radiation applications. In this paper, the glasses of cathode ray tubes (CRTs) have been used as powdered glass to make new samples with lead oxide (PbO) and potassium oxide (K₂O). Then, the optical and radiation properties of these samples have been investigated. The effects of 1% added of cerium oxide (CeO₂) on the radiation resistant and optical spectra differences have been measured. In addition, this research has environmental benefits that appear in reducing the toxic heavy metals that included in CRT glasses such as lead, barium, strontium and other metals. This paper discuses a new an approach to recycle the CRT glass. The glass transition temperatures (T_g) and the structure of these samples have been investigated by using the differential temperature analysis (DTA) and X-Ray diffraction (XRD) respectively. The optical transmission spectra have been studied, and the transmission studied by using UV-Visible spectrometer and the optical transmission reached to about 85% in the visible spectrum range. Then, attenuation coefficients have been measured for photons emitted by Co⁶⁰. After that, the optical transmission before and after irradiation have been investigated. The results appeared that these spectra varying by radiation doses and related to the type of used glass in these samples. Where the transmission decreased about 20% to 50% in the beginning of the spectrum range from 400 nm to 600 nm at exposure doses that reached to 5 kGy and high dose rate which was 1 kGy/h. These spectra were not varying in some samples that contain the glass panel. These results agree with similar studies [1], where the density reached to 5.2g.cm^-3 and the refractive index equal to 1.8, and the value of transmission closed to 85%.

Keywords

Cathode Ray Tubes (CRT's), Radiation Shielding Glass, Recycling, Gamma Attenuation, UV-Visible Spectrometer, Differential Temperature Analysis, Radiation Dose

Reference

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