Enas Khalifa Mahfouz Khalifa <br/><br/>
Assessment of environmental hazards of natural radioactivity emitted and heavy elements exist in local cement in Egypt /  
 تقييم المخاطر البيئية للنشاط الإشعاعي الطبيعي المنبعث و العناصر الثقيلة الموجودة في الأسمنت المحلي في مصر     
Enas Khalifa Mahfouz Khalifa ; Supervised Saher Mohamed Darwish Ahmed , Mogahed Ebrahim Ali Alabyad 
 - Cairo :   Enas Khalifa Mahfouz Khalifa ,   2017 
 - 98 , 35 P. :   charts , facsimiles ;   25cm 
<br/><br/>Thesis (M.Sc.) - Cairo University - Faculty of Science - Department of Physics 
<br/><br/> The principal aim of this thesis is to investigate the radiological hazard for cement  samples and measure the heavy elements and toxic substances in them. Using Þ  spectrometry, the concentration of natural radionuclides 238U, 232Th and 40K has  been determined in cement and its raw materials which are utilized as construction  materials in Egypt. Twenty three samples of raw materials and final products  utilized in the cement factories were collected for study. Thirteen samples were  obtained from (Limestone, Clay, Slag, Clinker, gypsum) which represent the raw  materials utilized in cement industry and ten samples of final products of  commercial cement were obtained from (Portland, El-Mohands and White  cement). The activity concentration of 238U, 232Th and 40K in raw materials were  observed to be ranged from (56.32 to 615.59) Bq/kg, (11.47 to 77.05) Bq/kg and  (68.36 to 948.07) Bq/kg with mean value 134.07, 35.97 and 403.48 Bq/kg for 238U,  232 40 238 232 40  Th and K, respectively. The activity concentration of U, Th and K in  final products were observed to be ranged from (62.93 to 234.73 Bq/kg), (20.10 to  38.07 Bq/kg) and (200.53 to 306.58 Bq/kg) with mean value 93.49,29.64 and  257.90 Bq/kg for 238U, 232Th and 40K, respectively. The permissible activity levels  of building materials are (50, 50 and 500) Bq/kg for 226Ra, 232Th and 40K,  respectively [NEA-OECD, 1979 and UNSCEAR, 1993]. All concentration values  of 238U in raw materials and final products are higher than recommended value. The  concentration values of 232Th in raw materials and final products are lower than  recommended value except sample S1, S3, S8, S10 and S13. The concentration  values of 40K in raw materials and final products are lower than recommended  value except samples S3, S8 and S13. The results of concentration levels are  compared with other measurements from different parts of the world 
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<br/><br/><label>Subjects--Index Terms: </label>Environmental hazards Local cement in Egypt Natural radioactivity emitted