Depth dose calculations

TAEK;TUBITAK3rd International Conference on Theoretical and Experimental Studies in Nuclear Applications and Technology, TESNAT 2017 --10 May 2017 through 12 May 2017 -- --In this study, calorimetric method is used to derive the depth doses calculation. In the experiment at the KeV level, an Ir-192 source with three different gamma energies was used. The source activity is approximately 9.15 curie. The Ir-192 radioactive source is mainly used for industrial purposes. This study had been made to determine organ dose values in any industrial accident. The data are calculated as surface dose and depth dose. Values for different time intervals have been measured. Time and depth parameters for measurements and calculations were obtained for 30 different values. The results of the experiment and the calculations have been compared. © The Authors, published by EDP Sciences, 2017

Alpha induced reaction cross section calculations of tantalum nucleus

The fusion energy is attractive as an energy source because the fusion will not produce CO2 or SO2 and so fusion will not contribute to environmental problems, such as particulate pollution and excessive CO 2 in the atmosphere. The fusion reaction does not produce radioactive nuclides and it is not self-sustaining, as is a fission reaction when a critical mass of fissionable material is assembled. Since the fusion reaction is easily and quickly quenched the primary sources of heat to drive such an accident are heat from radioactive decay and heat from chemical reactions. Both the magnitude and time dependence of the generation of heat from radioactive decay can be controlled by proper selection and design of materials. Tantalum is one of the candidate materials for the first wall of fusion reactors and for component parts of irradiation chambers. Accurate experimental cross-section data of alpha induced reactions on Tantalum are also of great importance for thermonuclear reaction rate determinations since the models used in the study of stellar nucleosynthesis are strongly dependent on these rates (Santos et al. in J Phys G 26:301, 2000). In this study, neutron-production cross sections for target nuclei 181Ta have been investigated up to 100 MeV alpha energy. The excitation functions for (?, xn) reactions (x = 1, 2, 3) have been calculated by pre-equilibrium reaction mechanism. And also neutron emission spectra for 181Ta (?, xn) reactions at 26.8 and 45.2 MeV have been calculated. The mean free path multiplier parameters has been investigated. The pre-equilibrium results have been calculated by using the hybrid model, the geometry dependent hybrid (GDH) model. Calculation results have been also compared with the available measurements in literature. © 2012 Springer Science+Business Media, LLC

Alpha emission spectra of 27Al, 50,52Cr, 55Mn, 54,56Fe, 58,60Ni nucleus for neutron induced reaction

The design of novel nuclear facilities, fusion as well as fission reactors, requires the knowledge of all properties of relevant materials, including the nuclear differential cross sections for a careful selection. The nuclear cross sections data for gas production via particle (neutron, proton, alpha, etc.) induced reactions are great importance in the domain in the fusion reactor technology, particularly in the calculation of nuclear transmutation rates, nuclear heating and radiation damage due to gas formation. In fusion reactor structures, a serious damage mechanism has been gas production in the metallic resulting from diverse nuclear reactions, mainly through (n, p) and (n, ?), (n, d), (n, t). In the present study, by using equilibrium reaction mechanisms, the (n, x?) reaction alpha emission spectra for 27Al, 50,52Cr, 55Mn, 54,56Fe, 58,60Ni isotopes were investigated from 9 to 15 MeV incident neutron energy. The equilibrium results have been calculated by using the hybrid model, the geometry dependent hybrid model. Calculation results have been also compared with the available measurements in literature. © 2012 Springer Science+Business Media New York

The interplay between plasma membrane and endoplasmic reticulum Ca2+ATPases in agonist-induced temporal Ca2+ dynamics

PubMedID: 25331516A change in the intracellular free Ca2+ concentration ([Ca2+]i) functions as a transmitter for signal transduction and shows a broad temporal pattern. Even genetically homogeneous cell types show different Ca2+ response patterns under permanent agonist stimulation. In Ca2+ signaling, the dynamics of the Ca2+ release from the Ca2+ channels during continuous agonist stimulation and the simultaneous effect of the pumps are unclear. In this study, the dynamic interaction of the Ca2+ ATPases in the plasma membrane (PMCA) and the endoplasmic reticulum membrane (SERCA) during continuous ACh stimulation is monitored using Fluo-3 and Fura-2 loaded HEK 293 cells. We characterize Ca2+ release patterns at the sub-maximal and maximal stimulation doses in the absence of extracellular Ca2+. We analyze the responses regarding their types, oscillation frequency and response times. La3+ (PMCA blocker) do not change the frequency and time courses in sub-maximal ACh treatment, while with the maximal stimulation oscillation frequency increase as oscillations superimpose on robust release, and response time of [Ca2+]i is elongated. A similar effect of La3+ is observed in quantal Ca2+ release phenomenon. In the presence of CPA, a SERCA blocker, oscillations are completely abolished, but response time does not change. We also observe that during continuous receptor stimulation, Ca2+ release do not cease. These data may suggest that Ca2+ release continues during agonist stimulation, but SERCA and PMCA form a new steady state and return [Ca2+]i to its physiological concentration. © 2014, Springer Science+Business Media New York

Analysis of gamma emitting radionuclides (terrestrial and anthropogenic) in soil samples from Kilis province in south Anatolia, Turkey

In recent years, there has been great concern about analysis of radionuclide content in environmental samples (soil, water, etc.) in many countries. The aim of the present study is to analyze the activity concentrations of terrestrial (226Ra, 232Th and 40K) and anthropogenic (137Cs) radionuclides in surface soil samples collected from different locations in and around Kilis province using the high-resolution gamma spectrometer with HPGe detector and evaluate external ionizing radiation exposure in outdoor air. The mean values of the activity concentrations of 226Ra, 232Th, 40K and 137Cs in the soil samples were analyzed as 16.1, 15.0, 206.0 and 9.5 Bq kg-1, respectively. Evaluated values of absorbed gamma dose rate in outdoor air and the corresponding external annual effective dose varied from 5 to 75 nGy h-1 with a mean value of 25 nGy h-1 and 6-92 µSv with a mean value of 31 µSv, respectively. These mean values were found to be within acceptable limits. © 2013 Elsevier Ltd. All rights reserved.

Study of the radioactivity in environmental soil samples from Eastern Anatolia Region of Turkey

In this study, a detailed ?-ray spectrometer survey was performed to obtain the baseline data on natural and fallout radioactivity in soil samples (10-30 cm depth) collected from Igdlr which is a province in Eastern Anatolia Region of Turkey and located along the border with Armenia. Metsamor Nuclear Power Plant in Eastern Armenia is only about 20 km away from Igdlr province. The average activity concentrations of 226Ra, 232Th, 40K and 137Cs in the soil samples were found as 19.1±0.6 (range: 12.8-31.2 Bq kg-1), 21.9±0.6 (range: 11.6-36.8 Bq kg-1), 437.7±10.3 (range: 285.0-613.7 Bq kg-1) and 11.8±1.1 Bq kg-1, (range: 2.5-51.1 Bq kg-1), respectively. The radiological hazards caused by ionizing radiation emitted from these radionuclides on the population living in the region were assessed by estimating radiological parameters such as absorbed ? dose rate in outdoor and the corresponding annual effective dose rate from external exposure, annual effective dose rate from inhalation of radon and excess lifetime cancer risk. The results revealed that there is no significant radiological hazard for human population because the average values of radiological parameters are within the recommended limits. © 2018 Walter de Gruyter GmbH, Berlin/Boston

Natural radionuclide content of disposed phosphogypsum as TENORM produced from phosphorus fertilizer industry in Turkey

This study aims to determine radiological characterization of disposed phosphogypsum (PG) as technologically enhanced naturally occurring radioactive material produced from phosphorus fertilizer plants (PFPs) in Turkey and evaluate radiological impacts of outdoor storage and transport and the usage of PG as additive and filling materials in building sector and road construction. The mean activity concentrations of 226Ra, 232Th and 40K measured for the PG samples from PFP A and PFP B are 125.0, 15.1 and 7.5 Bq kg -1 and 436.0, 9.4 and 13.0 Bq kg -1, respectively. The mean activity concentrations of 226Ra, 232Th and 40K are also compared with available reported data from other countries in the literature. The mean value of radium equivalent activity (Ra eq) index calculated for the PFP A PG samples is 146.7 Bq kg -1 which is lower than the limit of 370 Bq kg -1 set for building materials and for the PFP B PG samples is 449.6 Bq kg -1 which is within the recommended safety limits for usability of PG as aggregate in making roads, streets, pavements and railroad ballast. Generic exposure scenarios given in the Radiation Protection 122 were used for radiological evaluation for members of the public and workers. The mean annual effective doses evaluated for members of the public and workers are lower than the annual limit of 1 mSv y -1. © 2012 Elsevier Ltd. All rights reserved

Tritium activity levels in drinking water of Adana, Turkey

Tritium activity in potable drinking water samples from Adana city were measured using liquid scintillation counting after distillation procedure. The results exposed that the activity concentrations of the tritium measured in one-third of these samples were lower than minimum detectable activity which has a value of 2 Bq/L for counting time of 1,500 min. However, the maximum and mean value of the tritium activity was found to be 9.1 Bq/L (77.3 TU) and 7.0 Bq/l (59.4 TU), respectively. These values were substantially below the 100 Bq/L which is normative limit in Turkey for waters intended for human consumption. The highest values of annual effective dose received by infants, children and adults due to measured tritium activity were estimated as 0.041, 0.057 and 0.120 µSv/y, respectively. © 2014 Akadémiai Kiadó, Budapest, Hungary

Evaluation of potential exposure risks of natural radioactivity levels emitted from building materials used in Adana, Turkey

In this paper, the natural radioactivity levels in a total of 117 samples of 14 different building materials collected from building construction sites and from the retailers in Adana were studied by means of gamma-ray spectrometer with HPGe detector. The mean activity concentrations of 226Ra, 232Th and 40K measured in the studied building material samples ranged from 2.1 to 88.2 Bq kg-1, 1.8 to 52.7 Bq kg-1 and 68.1 to 847.5 Bq kg-1 for 226Ra, 232Th and 40K radionuclide, respectively. The external and internal index, the indoor absorbed dose rate and the corresponding annual effective dose were evaluated for potential exposure risks from the usage of the building material samples. The evaluated values of the external and internal index were below the recommended upper level. All the values of effective annual dose determined were lower than recommended exemption level of 0.3 mSv. The results suggest that the use of the studied building material samples in the construction of buildings is unlikely to give rise to any significant radiation exposure to the residents. © The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.This study was carried out within the framework of a doctorate thesis conducted at Cukurova University and Nevsehir University. The authors remember Prof. Dr. Gülten Günel with respect

Aa survey of distribution of terrestrial radionuclides in surface soil samples in and around the osmaniye province, turkey

PubMedID: 23045718The purpose of this survey was to determine the distribution of terrestrial radionuclides (238U, 232Th and 40K) in surface soil samples collected from different locations in and around Osmaniye and assess the radiological implications of outdoor external exposure. The activity concentrations of 238U, 232Th and 40K in soil samples ranged from 2.6 to 38.1 Bq kg21 with a mean of 10.4±0.7 Bq kg21, 3.7-40.5 Bq kg21 with a mean of 12.2±0.7 Bq kg-1 and 30.0-639.7 Bq kg-1 with a mean of 243.4±12.8 Bq kg-1, respectively. The concentrations of these radionuclides, presented in this article, were compared with those obtained from similar studies related to Turkey reported in the literature as well as earth's crust average values. The results of the activity concentrations were used to assess the external absorbed gamma dose rate (GDR) in outdoor air and the annual effective dose (AED). The outdoor absorbed GDRs fluctuate from 5.2 to 53.6 nGy h-1 with a mean of 22.4±9.5. The corresponding mean AED is found to be 0.03 mSv. © The Author 2012. Published by Oxford University Press. All rights reserved