Document Details
Document Type |
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Thesis |
Document Title |
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Development of Novel Composite Ionizing Radiation Shields for Medical Applications تطوير دروع لمركبات جديدة للأشعاع المؤين للتطبيقات الطبية |
Subject |
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Faculty of Science |
Document Language |
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Arabic |
Abstract |
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X-rays and gamma rays were discovered in 1895 and 1900 respectively. Later in the 19th century, high-energy beta particles also found applications in medicine. Since the discovery of these ionizing radiations, they have transformed many areas of life like medicine, industry, agriculture etc. Because of their high usage in medicine especially, there occurred the need for these ionizing radiations to be shielded in their cause of application due to the evident harmful effects which resulted from their applications. These radiations are used in diagnostic radiology, nuclear medicine, radiotherapy and many areas in medicine.
Currently, there exist different polymer composites in the literature which are fabricated for radiation shielding purposes. Polymer composites are used nowadays because they are lighter, tougher, easy to fabricate and relatively inexpensive. Different matrixes and fillers have been used as seen in the literatures in developing polymer composites. Additionally, different heavy oxide glasses have also been reported for different radiation shielding applications.
However, to the best of our knowledge, few/no research works have considered a biodegradable polymer matrix like cellulose acetate and few works have also reported the use of more than one filler in fabricating polymer composites meant for shielding purposes. In addition, very few/no works have reported the use of transparent glass for radiation shielding purposes especially at low energies for medical applications (diagnostic radiology).
In this work, cellulose acetate composites and transparent heavy metal oxide glasses were investigated for their abilities in shielding ionizing radiation for medical applications. Cellulose acetate (matrix) and different oxides (fillers) were fabricated using the open mould cast technique; they were tested using x-rays at different voltages (40, 60, 80 and 100kVp). The composites were: cellulose acetate-ZnO-SnO2; cellulose acetate-CdO-ZnO; cellulose acetate/Fe2O3; cellulose acetate/Gd2O3. All the samples were characterized using scanning electron microscopy (SEM) technique, Fourier Transform Infrared Spectroscopy (FTIR) and X-ray powder diffraction (XRD) technique. The samples were exposed to x-rays of voltages: 40, 60, 80 and 100kVp. The linear attenuation coefficient (LAC) and half value layer (HVL) of the samples were determined. The results showed that all the samples considered in this work are potential shielding materials that could be used for medical application. Furthermore, the transparent erbium zinc tellurite glass systems and transparent bismuth tellurite glass systems were investigated in this work. The physical properties of these glasses were obtained from the literatures. The radiation shielding properties of these glasses were determined at average energies used in diagnostic radiology (20, 30, 40 and 60 keV). The mass attenuation coefficients were determined using WinXCom computer program while other parameters were obtained using the relevant equations. Moreover, Beta particles shielding properties were also determined using the transparent bismuth tellurite glass system at 1.495, 1.71 and 2.26 MeV using ESTAR computer program and other necessary equations. The results showed that all these transparent glasses are potential substitute for lead glass at the energies considered in this work. |
Supervisor |
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Prof. Dr.Yas Al-Hadeethi |
Thesis Type |
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Doctorate Thesis |
Publishing Year |
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1441 AH
2019 AD |
Added Date |
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Thursday, September 19, 2019 |
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Researchers
سيد اديمة لاتجاني | Tijani, Saheed Ademola | Researcher | Doctorate | |
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