Barium Sulfate Epoxy Mixture Effects on Attenuation of Short Wavelength Radiation

Introduction There are three factors which are used to control the amount or dose of radiation received from a source. The radiation exposure can be managed by a combination of these factors; • Time: reducing the time of an exposure leads to reduction of the effective doses proportionally. • Shielding: refers to a mass of absorbing material placed around a reactor or other radioactive source in order to reduce the radiation to safe humans [1]-[5]. Radiation protection is a very important field and many researchers have tried to approach the best methods for protection from radiation during the last centuries. The studies mostly concentrated on protection against electromagnetic radiation due to its serious risk to humans, and then on the methods of protection against gamma rays, and it’s scattering [6]. An electronic dose conversion unit was developed to estimate the environmental dose rate directly without using an MCA (multichannel analyzer). The experimental test of the new system with standard gamma sources showed good agreement with the calculated exposure dose rate. Therefore, the developed system using a NaI(T1) detector and the electronic dose conversion unit can be used to monitor the low-level range of environmental radiation accurately and reliably. The requirements of high performance shielding material are to maximize the number of electrons per unit mass, the nuclear reaction cross section per unit mass and the production of secondary particles. Thus, the transmitted LET (linear energy transmission) spectra of hydrogen showed acceptable universal attenuation at low keV/m measurement resulting in good attenuation of biological effects independent of biological model, which was used. The source used is Cesium-137 for 0.662 MeV. It is found that the count average of gamma photons increases when the scattering material thickness increases [7]. The phantom experiment suggests that fetal irradiation during maternal chest CT can be reduced substantially with barium shielding. Scattered radiation was attenuated at 13% and 21% with 2% of barium sulfate, and it attenuated to 87% and 96% with 40% barium sulfate, as calculated in the near and far fields respectively. The extrapolated attenuations for 5%–40% barium sulfate suspensions indicated that beyond a 30% suspension, attenuation increased further only slightly [8]. Increased concrete density is obtained by complex use of waste products of heavy silicate–lead glasses (brand DF) production as dispersed cement filler, disperse superlasticizer (SP) carrier, fine and coarse fillers. It was found the optimal ratio of solution filling with optical glass additive makes 8% – 12.5% from cement weight. Increase of glass share up to 20% and more leads to decrease the durability of fine sand solution. Also, the compression resistance of this concrete is 92 MPa at (W/C=0.24) before it collapses when granite filler at watercement relation (W/C=0.29) [9]. Another research measured the doses of x – ray that pass through different mixture of the blocks and showed that the protection could be improved by increasing the ratios of barium sulfate. So, the results indicated that when the ratios of barium sulfate increases, the dose of xray decreases. High energy (70 KV) and low energy (47 KV) of x –ray machine was used. The ratios of barium sulfate-cement were (0%, 25%, 30%, 35%, 40%, 45% and 50%) in various thicknesses of the blocks (2, 4, 6, 8 and 10 mm), so the results for high energy at various thicknesses and ratios of barium sulfates were between 388 and 26.1 μ sv/h and for low energy was between 113 and 0.99 μ sv/h. The thickness of the mixture blocks affected on x–ray transmission [10]. Barium Sulfate Epoxy Mixture Effects on Attenuation of Short Wavelength Radiation Khalid Omar, Khaled Abdu Al-Khazaleh and Saif Ali Saadi 1 DMPS, College of Art and Sciences, University of Nizwa, Nizwa, Oman . 2 Department of Physics, Faculty of Science, Al-albayt Univesity, Mafraq, Jordan. School of Physics, University Sains Malaysia, 11800 Penang, Malaysia.