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  • Author or Editor: A. Ashraf x
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Abstract  

Three Egyptian monazite samples from the beach black sand at Abou Khashba near Rosetta, submitted by the laboratories of the nuclear materials authority of Egypt were analyzed for elemental contents, using Prompt gamma ray neutron activation analysis (PGNAA) as an effective analysis technique especially for rare earth elements. An integrated system for PGNAA, located at hot Lab. Center, has proven useful for the analytical purpose using 252Cf neutron source with neutron flux of 6.16E7 n/cm2 s, that system has been designed and calibrated for PGNAA. Sensitivity curves using different standard concentration values of artificial liquid standards samples at different concentrations ranging from 1,000 to 5,000 mg/L in case of Sm and Gd, while from 100 to 1,000 mg/L for Eu, have been constructed. The average concentration values for Gd, Sm and Eu in the samples under investigation was at 1.46E4 ± 0.21, 6.683E4 ± 0.14 and 440 ± 0.18 ppm, respectively. A comparative study of the obtained results and the results of ICP-Ms was given.

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Abstract  

Water hyacinth (Eichhornia crassipes) is known to accumulate elements from rivers and a good tool for water monitoring. To test the usefulness of such an aquatic plant as a bioindicator, we have determined the levels of Na, Ca, Cr, Fe, Co, Zn, As, Rb, Zr, Sb, Cs, La, Ce, Nd, Sm, Eu, Tb, Yb, Hf, Ta, Th, and U in water hyacinth around industrial facilities and along the studied area by instrumental neutron activation analysis. The concentrations of Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, and Pb were determined in upstream river water and effluent factories. Contamination factor, and pollution load index was calculated. The results show that higher concentrations as well as bioaccumulation factors of these elements were observed in water hyacinth samples around the industrial facilities. On the other hand a decrease in calcium concentration was observed as a result of the thermal pollution of Nile river water. The pollution load index for the studied area was estimated to be 4.2.

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