The natural radioactivities in three major groups of foodstuff widely consumed in Upper Egypt were de- termined. The specific activities of 226Ra, 232Th, and 40K in cereals, leguminosae, and flour were measured using ...The natural radioactivities in three major groups of foodstuff widely consumed in Upper Egypt were de- termined. The specific activities of 226Ra, 232Th, and 40K in cereals, leguminosae, and flour were measured using γ-ray spectroscopy. Another group of hay, water, and soil samples from the same location were also analyzed. Hay samples were found to contain the highest radioactivity concentration among all the samples that were investigated. This in- crement could be due to the high water content in the shoots which tends to accumulate soluble radionuclides. The average calculated concentrations of soil samples in the present study exhibits the lowest values with respect to those from different countries. In the case of water samples, the average activities of both 232Th and 40K were similar to those for soil while 226Ra was twice that of water sample. The annual ingestion dose from each radionuclide was cal- culated. The computed annual dose owing to daily intake of radium, thorium, and potassium via wheat flour, lentils, and bean in the present study (214.8 μSv) is ten times lower than the global average annual radiation dose (2400 μSv) from the natural radiation sources as proposed by UNSCEAR. The obtained results show that the dose values are quite low and carry insignificant radiation dose to the public.展开更多
Different samples of igneous and metamorphic rocks from Egypt and Germany have been considered to measure γ-ray activity concentrations due to naturally occurring, potentially hazardous radonuclides 226Ra, 232Th and ...Different samples of igneous and metamorphic rocks from Egypt and Germany have been considered to measure γ-ray activity concentrations due to naturally occurring, potentially hazardous radonuclides 226Ra, 232Th and 40K. The radiation hazard parameters including radiation equivalent activity, gamma-absorbed dose rate, and exter- nal and internal hazard indices have been estimated. The gamma-absorbed dose rates in air of rocks in Egypt range from 4.2 to 128.5 nGy·h-1 with a mean value of 55.3 nGy·h-1. For igneous and metamorphic rocks from Germany, the values of absorbed dose rates fluctuate from 5.1 to 148.6 nGy·h-1, with a mean value of 60.9 nGy·h-1. Generally, it is found that the radiation hazard indices in common igneous rocks are distinctly higher in acidic than in ultrabasic rocks. The results are discussed and compared with the corresponding published data.展开更多
Samples of cement manufactured in Egypt and the raw materials have been analyzed usinggamma-spectroscopy, in order to determine the concentration of natural radionuclides and associated radiologicalhazard. The mean of...Samples of cement manufactured in Egypt and the raw materials have been analyzed usinggamma-spectroscopy, in order to determine the concentration of natural radionuclides and associated radiologicalhazard. The mean of specific activity due to radionuclides of 226 Ra, 232 Th and 40 K was found to be (20±4), (11± 2),(320±18) (gypsum), (41±8), (27±5), (410±27) (clay), (58±11), (18±3), (321±20) (iron ore) and (37.6±6), (11.8±3),(178.6±15) Bq?kg -1 (Portland cement), respectively. 40 K concentration could not be detected in slag, limestone, sul-phateresistant cement (S.R.C.), clinker and white cement, while the mean specific activities of 226 Ra and 232 Th are(239±16), (48.7±7); (31.5±5), (10±2); (47±7), (20±5); (23±5), (10.4±3) and (23±5), (11±3) Bq?kg -1 , respectively. Theactivities (concentrations) are in the same range as the data released in other countries. The calculated radiation haz-ardparameters for all the samples are still lower than the acceptable values in Egypt and other countries.展开更多
文摘The natural radioactivities in three major groups of foodstuff widely consumed in Upper Egypt were de- termined. The specific activities of 226Ra, 232Th, and 40K in cereals, leguminosae, and flour were measured using γ-ray spectroscopy. Another group of hay, water, and soil samples from the same location were also analyzed. Hay samples were found to contain the highest radioactivity concentration among all the samples that were investigated. This in- crement could be due to the high water content in the shoots which tends to accumulate soluble radionuclides. The average calculated concentrations of soil samples in the present study exhibits the lowest values with respect to those from different countries. In the case of water samples, the average activities of both 232Th and 40K were similar to those for soil while 226Ra was twice that of water sample. The annual ingestion dose from each radionuclide was cal- culated. The computed annual dose owing to daily intake of radium, thorium, and potassium via wheat flour, lentils, and bean in the present study (214.8 μSv) is ten times lower than the global average annual radiation dose (2400 μSv) from the natural radiation sources as proposed by UNSCEAR. The obtained results show that the dose values are quite low and carry insignificant radiation dose to the public.
文摘Different samples of igneous and metamorphic rocks from Egypt and Germany have been considered to measure γ-ray activity concentrations due to naturally occurring, potentially hazardous radonuclides 226Ra, 232Th and 40K. The radiation hazard parameters including radiation equivalent activity, gamma-absorbed dose rate, and exter- nal and internal hazard indices have been estimated. The gamma-absorbed dose rates in air of rocks in Egypt range from 4.2 to 128.5 nGy·h-1 with a mean value of 55.3 nGy·h-1. For igneous and metamorphic rocks from Germany, the values of absorbed dose rates fluctuate from 5.1 to 148.6 nGy·h-1, with a mean value of 60.9 nGy·h-1. Generally, it is found that the radiation hazard indices in common igneous rocks are distinctly higher in acidic than in ultrabasic rocks. The results are discussed and compared with the corresponding published data.
文摘Samples of cement manufactured in Egypt and the raw materials have been analyzed usinggamma-spectroscopy, in order to determine the concentration of natural radionuclides and associated radiologicalhazard. The mean of specific activity due to radionuclides of 226 Ra, 232 Th and 40 K was found to be (20±4), (11± 2),(320±18) (gypsum), (41±8), (27±5), (410±27) (clay), (58±11), (18±3), (321±20) (iron ore) and (37.6±6), (11.8±3),(178.6±15) Bq?kg -1 (Portland cement), respectively. 40 K concentration could not be detected in slag, limestone, sul-phateresistant cement (S.R.C.), clinker and white cement, while the mean specific activities of 226 Ra and 232 Th are(239±16), (48.7±7); (31.5±5), (10±2); (47±7), (20±5); (23±5), (10.4±3) and (23±5), (11±3) Bq?kg -1 , respectively. Theactivities (concentrations) are in the same range as the data released in other countries. The calculated radiation haz-ardparameters for all the samples are still lower than the acceptable values in Egypt and other countries.
