الفهرس 
Radioactive nuclides in natureOnly 14 pages are availabe for public view
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Abstract
In order to illustrate the assessment of natural radioactivity and radiation hazard at Qash Amir – El Sela area, it is necessary to integrated ground γ-ray spectrometric data, hyper pure germanium (HPGe) γ-ray spectrometer analysis, radon detection and X-ray analysis data, with detailed descriptions. The environmental assessment of Sela using RS-320 portable spectrometer has found eU vary between 15.4 and 3700 (ppm), eTh vary between 6.6 to 40 (ppm) and K ranged from 2.1 to 6.3 (%).The value of eU/eTh ratio is ranged from 0.97 to 251.7. it determines the uranium enrichment in the study area.
Forty-seven samples of granites collected from Sela area, Southern Eastern Desert, Egypt have been investigated. The activity concentrations of 238U, 232Th, and 40K radionuclides in the samples were determined by gamma ray spectrometer using HPGe detector with especially designed shield. The concentration of238U, 232Th and 40K (Bq/Kg) has been observed to be ranged from (179 to102451), (17 to 8823) and (467 to 1923) Bq/Kg with mean value6989, 796and 1127 respectively. The main activity concentration of 238U, 232Th and 40K are 212, 23 and 2.7 times that of the international recommended limits 33, 35 and 412(Bq/Kg), respectively. The values of radium equivalent (Bq/Kg), radioactivity level index, external hazard, dose rate (nGy/h), annual effective dose equivalent (mSv/y), excess life time cancer risk and annual gonadal dose equivalent indicated that most Sela area granite samples are higher than the permissible levels.
The XRF analysis showed that the concentration of the major and trace elements of El-Sela samples are containing high concentration of Barium (Ba) and Zircon (Zr),where Ba is ranged from 40 to 5809 ppm and Zr is ranged from 142 to 2047 ppm.
The radon emanation coefficients technique, which contains CR-39solid-state detector, used to measure radon concentration from47 samples of granite from Sela area. The calculated radon concentrations of El-Sela area are ranged from 1031 to 37478 (Bq/m3).
The concentrations of eU, eTh, and K were measured by portable RS-320 spectrometer for Gabel Sela and Gabel Qash Amer. The values of eU vary between 6.1to 373 ppm, values of eTh vary between 4.8 to 41 ppm and K ranged from 1 to 5.7 %.The estimated eU/eTh ratio ranged from 0.05 to 3.9 which confirms the high concentration of eU area reflecting increase in uranium content.
The activity concentrations of 238U, 232Th, and 40K radionuclides in the samples were determined by gamma ray spectrometer using HPGe detector with especially designed shield. The average concentration of238U, 232Th and 40K (Bq/Kg) has been observed to be varied between (61 and5396), (34 and 1998) and (114 and 1955) Bq/Kg with mean value 577, 175 and 1203 for 238U, 232Th and 40K respectively. The main activity concentration of 238U, 232Th and 40K are 17.5, 5 and 2.9 times that of the international recommended limits 33, 35 and 412(Bq/Kg), respectively. The values of radium equivalent (Bq/Kg), radioactivity level index, external hazard, dose rate (nGy/h), annual effective dose equivalent (mSv/y), excess life time cancer risk and annual gonadal dose equivalent indicated that most Gabel Sela and Gabel Qash Amer area granite samples are higher than the permissible levels.
The XRF analysis showed that the concentration of the major and trace elements Gabel Sela and Gabel Qash Amer samples are containing high concentration of Barium (Ba) and Strontium (Sr). where Ba varied from 37 and 4924 ppm and Sr ranged from 3 to 2753 ppm.
The can technique, which contains CR-39solid-state detector, used to measure radon concentration from Gabel Sela and Gabel Qash Amer area south eastern desert Egypt granite samples. The measurements were made in 23 samples of granite from Gabel Sela and Gabel Qash Amer area. We calculate Radon concentration (Bq/m3), Annual absorbed dose (DT) (mSv/y), annual equivalent dose (HT) (mSv/y) and annual effective dose (to lungs) (ET) (mSv/y).Radon concentration ranged from 610 to 3137 (Bq/m3).