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ABSTRACT: Some building materials, regularly used in Turkey, such as sand, cement, gas concrete (lightweight, aerated concrete), tile and brick, have been investigated in terms of mass attenuation coefficient (μ/ρ), effective atomic, numbers (Z(eff)), effective electron densities (N(e)) and photon interaction cross section (σ(a)) at 14 different energies from 81- to 1332-keV gamma-ray energies. The gamma rays were detected by using gamma-ray spectroscopy, a High Purity Germanium (HPGe) detector. The elemental compositions of samples were analysed using an energy dispersive X-ray fluorescence spectrometer. Mass attenuation coefficients of these samples have been compared with tabulations based upon the results of WinXcom. The theoretical mass attenuation coefficients were estimated using the mixture rule and the experimental values of investigated parameters were compared with the calculated values. The agreement of measured values of mass attenuation coefficient, effective atomic numbers, effective electron densities and photon interaction cross section with the theory has been found to be quite satisfactory.
Radiation Protection Dosimetry 11/2011; 150(4):541-9. · 0.82 Impact Factor
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ABSTRACT: Different cement samples commonly used in building construction in Turkey have been analyzed for natural radioactivity using gamma-ray spectrometry. The mean activity concentrations observed in the cement samples were 52, 40 and 324 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries and world average limits. The radiological hazard parameters such as radium equivalent activities (Ra(eq)), gamma index (I(gamma)) and alpha index (I(alpha)) indices as well as terrestrial absorbed dose and annual effective dose rate were calculated and compared with the international data. The Ra(eq) values of cement are lower than the limit of 370 Bq kg(-1), equivalent to a gamma dose of 1.5 mSv y(-1). Moreover, the mass attenuation coefficients were determined experimentally and calculated theoretically using XCOM in some cement samples. Also, chemical compositions analyses of the cement samples were investigated.
Journal of hazardous materials 12/2009; 176(1-3):644-9. · 4.14 Impact Factor
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ABSTRACT: The natural radioactivity due to the presence of (226)Ra, (232)Th and (40)K in sand samples used as building materials in Turkey was measured by gamma spectrometry. The measured activity in the sand samples ranged from 17 to 97 Bq kg(-1), 10 to 133 Bq kg(-1) and 116 to 955 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The concentrations of these natural radionuclides were compared with the reported data for other countries. The radium equivalent activity (Ra(eq)), the external hazard index (H(ex)), the internal hazard index (H(in)), the indoor absorbed dose rate in air and the annual effective dose rate were evaluated to assess the radiation hazard for people living in dwellings made of the materials studied. The Ra(eq) values of sand samples are lower than the limit of 370 Bq kg(-1), equivalent to a gamma dose of 1.5 mSv yr(-1). This study shows that the measured sand samples do not pose any significant source of radiation hazard and are safe for use in building materials. Moreover, the experimental mass attenuation coefficients (mu/rho) of seven different sand samples were determined in the energy range 80-1332 keV photons by using the gamma ray transmission method. Experimental values of mass attenuation coefficient were compared with theoretical values obtained using the program XCOM. The calculated values and the experimental results of this work and the other results in the literature are found to be in good agreement. Chemical and structural analyses (XRD) of the sand samples were also undertaken.
Journal of Radiological Protection 04/2009; 29(1):61-74. · 1.39 Impact Factor
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ABSTRACT: The activity concentration of (226)Ra, (232)Th and (40)K in gas concrete samples collected from different suppliers and some provinces in Turkey were measured using gamma-ray spectrometry. Knowledge of radioactivity in gas concrete used in building materials enables one to assess any possible radiological risks to human health. The mean activity concentrations observed in the gas concrete samples were 82.0, 28.2 and 383.9 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The radium equivalent activity, external and internal hazard indices as well as terrestrial absorbed dose and annual effective dose rate was calculated. The results indicate that the radium equivalent activity values of gas concrete samples are lower than the limit of 370 Bq kg(-1), equivalent to a gamma-dose of 1.5 mSv y(-1). Moreover, mass attenuation coefficients were measured in some gas concrete samples. It was found that the mass attenuation coefficients decreased with increasing photon energies. Also, chemical compositions and structural analysis (XRD and SEM) of the gas concrete samples were investigated.
Journal of hazardous materials 03/2009; 168(2-3):681-7. · 4.14 Impact Factor
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ABSTRACT: In the present work, naturally occurring radionuclides of (226)Ra, (232)Th and (40)K were measured in soil samples collected from the Eastern Black Sea region of Turkey. It was found that the activity concentrations ranged from 12 to 120Bqkg(-1) for (226)Ra, from 13 to 121Bqkg(-1) for (232)Th and from 204 to 1295Bqkg(-1) for (40)K. Besides naturally occurring radionuclides, (137)Cs activity concentration was measured in soil, lichen and moss samples and it was found that (137)Cs activity concentration ranged from 27 to 775Bqkg(-1) with for soil, from 29 to 879Bqkg(-1) for lichen and from 67 to 1396Bqkg(-1) for moss samples. Annual effective doses due to the naturally occurring radionuclides and (137)Cs were estimated. Ecological half-lives of (137)Cs in lichen and moss species were estimated. The decrease of the activity concentrations in the present measurements (2007) relative to those in 1993 indicated ecological half-lives between 1.36 and 2.96 years for lichen and between 1.35 and 2.85 years for moss species.
Journal of Hazardous Materials 06/2008; 162(1):146-53. · 4.17 Impact Factor
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ABSTRACT: Indoor radon survey and gamma activity measurements in soil samples were carried out in the Giresun province (Northeastern Turkey). The result of analysis of variance showed a relationship between indoor radon and radium content in soil (R(2)=0.54). It was found that indoor radon activity concentration ranged from 52 to 360 Bq m(-3) with an average value of 130 Bq m(-3). A model built by BEIR VI was used to predict the number of lung cancer deaths due to indoor radon exposure. It was found that indoor radon is responsible for 8% of all lung cancer deaths occurring in this province. (137)Cs activity concentration was measured 21 years after the Chernobyl accident. The results showed that (137)Cs activity concentration ranged from 41 to 1304 Bq kg(-1) with an average value of 307 Bq kg(-1). The indoor radon results and the geology of the studied area were discussed. Annual effective doses to the both radionuclides of natural origin and (137)Cs were estimated.
Journal of Environmental Radioactivity 02/2008; 99(8):1349-54. · 1.34 Impact Factor
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ABSTRACT: The Eastern Black Sea Region of Turkey is one of the main hazelnut producers in Turkey and in the world. Since this region was contaminated by the Chernobyl accident in 1986, a comprehensive study was planned and carried out to determine the radioactivity level in hazelnut growing region. The dose due to consumption of hazelnut by the public was estimated and it was shown that this dose imposes no threat to human health. In addition, heavy metal analysis was performed in the samples and the amount of Cr, Mn, Fe, Ni, Cu, Zn, and Pb were also detected. The results showed that the concentrations of heavy metal are below the daily intake recommended by the international organizations.
Food and Chemical Toxicology.
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ABSTRACT: The activity concentration of 226Ra, 232Th and 40K in gas concrete samples collected from different suppliers and some provinces in Turkey were measured using gamma-ray spectrometry. Knowledge of radioactivity in gas concrete used in building materials enables one to assess any possible radiological risks to human health. The mean activity concentrations observed in the gas concrete samples were 82.0, 28.2 and 383.9 Bq kg−1 for 226Ra, 232Th and 40K, respectively. The radium equivalent activity, external and internal hazard indices as well as terrestrial absorbed dose and annual effective dose rate was calculated. The results indicate that the radium equivalent activity values of gas concrete samples are lower than the limit of 370 Bq kg−1, equivalent to a gamma-dose of 1.5 mSv y−1. Moreover, mass attenuation coefficients were measured in some gas concrete samples. It was found that the mass attenuation coefficients decreased with increasing photon energies. Also, chemical compositions and structural analysis (XRD and SEM) of the gas concrete samples were investigated.
Journal of Hazardous Materials.
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ABSTRACT: Different cement samples commonly used in building construction in Turkey have been analyzed for natural radioactivity using gamma-ray spectrometry. The mean activity concentrations observed in the cement samples were 52, 40 and 324 Bq kg−1 for 226Ra, 232Th and 40K, respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries and world average limits. The radiological hazard parameters such as radium equivalent activities (Raeq), gamma index (Iγ) and alpha index (Iα) indices as well as terrestrial absorbed dose and annual effective dose rate were calculated and compared with the international data. The Raeq values of cement are lower than the limit of 370 Bq kg−1, equivalent to a gamma dose of 1.5 mSv y−1. Moreover, the mass attenuation coefficients were determined experimentally and calculated theoretically using XCOM in some cement samples. Also, chemical compositions analyses of the cement samples were investigated.
Journal of Hazardous Materials.
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ABSTRACT: Nickel diffusion in CuInSe2 thin films was studied in the temperature range 430–520 °C. Thin films of copper indium diselenide (CuInSe2) were prepared by selenization of CuInSe2–Cu–In multilayered structure on glass substrate. A thin film of Nickel was deposited and annealed at different temperatures. Surface morphologies of the Ni diffused and undiffused CuInSe2 films were investigated using scanning electron microscope. The alteration of Nickel concentration in the CuInSe2 thin film was measured by Energy Dispersive X-Ray Fluorescence (EDXRF) technique. These measurements were fitted to a complementary error function solution and the diffusion coefficients at four different temperatures were evaluated. The diffusion coefficients of Ni in CuInSe2 films were estimated from concentration profiles at temperatures 430–520 °C as D = 1.86 × 10− 7(cm2s− 1)exp[− 0.68(eV)/kT].
Thin Solid Films 517(9):2851-2854. · 1.89 Impact Factor
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ABSTRACT: In this study the natural radioactivity in marble samples used in Turkey was measured by means of gamma spectrometry. The results showed that the specific activities of 226Ra, 232Th and 40K ranged from 10 to 92 Bq kg−1, from 4 to 122 Bq kg−1 and from 28 to 676 Bq kg−1, respectively. The radiological hazards in marble samples due to the natural radioactivity were inferred from calculations of radium equivalent activities (Raeq), indoor absorbed dose rate in air values, the annual effective dose and gamma and alpha indexes. These radiological parameters were evaluated and compared with the internationally recommended values. The measurements showed that marble samples used in Turkey have low level of natural radioactivity; therefore, the use of these types of marble in dwellings is safe for inhabitants. Mass attenuation coefficients (μ/ρ) were obtained both experimentally and theoretically for different marble samples produced in Turkey by using gamma-ray transmission method. Experimental values showed a good agreement with the theoretical values.
Annals of Nuclear Energy.
