title: Disequilibrium in naturally occurring radioactive series in some phosphate ores.
abstract: Eight phosphate ore samples from Egypt and Saudi Arabia were studied by atomic absorption spectrometry for the Bi, Pb, Th and Al concentrations in ppm or ppb or per cent. Also X-ray diffraction spectrometry was applied for determining the mineral and chemical composition of the phosphate ore samples. A gamma spectrometry system, based on HPGe crystal, was applied for determining the concentrations of the radioactive elements in (238)U, (226)Ra and (232)Th series as well as (40)K, in Bq/kg dry weight. Concentrations in ppm were found to be from <10.0 to 20.48, from <7.50 to 27.30 and from <1.0 to 50.0 for Bi, Pb and Th, respectively. Al ranged from <0.05 to 3.13%. Major, minor and trace chemical and mineral compositions were assigned for each sample by XRD spectrometry. Concentrations of the different elements in both radioactive series, (238)U, (226)Ra and (232)Th were compared. Disequilibrium was found in both series.
authors: King Abd Elaziz University, Faculty of Science, Girls Section, Jeddah, Saudi Arabia. Safiahqh@yahoo.com
authors: Safia H Q
authors: SH
authors: Hamidalddin
authors: Afaf A
authors: AA
authors: Fakeha
authors: Mai S
authors: MS
authors: Yeslam
authors: Nagdya M
authors: NM
authors: Ibraheim
mesh_terms: D001417:Background Radiation; D004534:Egypt; D010710:Phosphates / Q000032:analysis* / Q000737:chemistry*; D011829:Radiation Dosage; D011868:Radioisotopes / Q000032:analysis*; D011874:Radiometry / Q000379:methods*; D012529:Saudi Arabia; D012990:Soil Pollutants, Radioactive / Q000032:analysis*
chemical_list: D010710:Phosphates; D011868:Radioisotopes; D012990:Soil Pollutants, Radioactive