الفهرس 
CHAPTER 1 INTRODUCTION AND LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
The main target of this study is to find the effect of physical and chemical properties on the distribution of different radionuclide in different phases of different sedimentary rocks in Um Bogma Formation from Farsh El Azraq area in Sinai.
In First stage, the activity concentrations (Bq/kg) of the naturally occurring radionuclide’s 238U,235U,234U, 226Ra, 232Th, and 40K were measured by using high purity germanium detector (HpGe) and the activity ratios 226Ra/238U, 234U/238U, 238U/235U, 234U/235U were calculated to estimate the radioactive equilibrium/disequilibrium in the area under study, also the radiation hazard indices (external hazard index, radium equivalent, absorbed dose, outdoor annual effective dose rates, excess lifetime cancer risk and annual gonadal dose equivalent) were calculated. The radon emanation factor, the radon mass exhalation rate and radon annual effective dose have been calculated in these locations.
The results shown that, the concentrations of determined radionuclides are changed for each type of sedimentary rocks. The activity concentration by Bq/ kg for 238U, 226Ra, 232Th and 40K varied between [717.09 ± 21.51 and 6819.65 ± 204.59] (Bq/kg), [842.86 ± 25.28 and 9666.95 ± 290.01] (Bq/kg), [29.85 ± 0.89 and 170.46 ± 5.11] (Bq/kg) and [345.38 ± 10.36 and 856.54 ± 25.70] (Bq/kg), respectively were higher than the world’s average.
All radiation hazard indices have high values. All the studied samples measurements indicate high levels of annual effective dose from radon in these locations.
In Second stage, the three selected samples were treated by the analytical technique XRF, to measure the concentration of the major and trace elements. The samples are characterized by a high concentration of Zn and Ba, accordingly, it can be separated in order to use in different important industries.
In Third stage, Chemical analyses after leaching procedures to examine the mobility of uranium, thorium and their isotopes and daughters during the acid leaching and comparison between physical and chemical behaviors.
The results presented that the sum of activities of 238U and its daughters in both pregnant solutions and residuals are nearly equal the activity in the original sample. The nuclides in the 238U decay series before 226Ra are easily free in the pregnant solutions than the 226Ra itself and the nuclides after it (214Pb and 214Bi), these are concentrated in the residuals. The lowest leachability in all the samples is present in 226Ra, 214Pb and 214Bi.These results can explain the difference in behavior between the daughters before and after 226Ra series during natural weathering and alterations of uraniferous-rock materials. The 235U has nearly the same leachability as 238U, while 232Th is stable except in the presence of organic matters.
In Fourth stage, two methods were used to analyze the rare earth elements (REE) in elemental analysis by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and in natural by hyper pure germanium (HPGe) detector and then comparing between two methods by factor.
The results showed that the concentrations of Yttrium (Y) in three selected samples are higher than the other rare earth elements. It is noticed that, the computed ratio between radioactive rare earth elements to total elements, (chemically analyzed) is constant for each element in all the selected samples.
This explains that if these results are supported, so the use of the HPGe detector can be developed to identify some radioactive rare earth elements instead of using chemical methods, and this has many advantages, including that the Germanium detector is accurate, non-destructive testing and cheaper than other devices.