Journal of Nuclear Sciences

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https://dspace.ankara.edu.tr/handle/20.500.12575/39762

The Journal of Nuclear Sciences (JNS) is published on behalf of Ankara University Institute of Nuclear Sciences, on behalf of Ankara University. The printing costs for the print version of the journal are supported by Ankara University, while the online version is provided free of charge by DergiPark ULAKBİM services. The Dergipark system does not require any subscription from readers. Everyone can access the articles free of charge. The Journal of Nuclear Sciences (JNS) is an open access and cost-free peer-reviewed international scientific journal acting in the field of nuclear sciences. No author fee is charged from beginning to end during the submission, evaluation, and publication of the article to the journal.

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Now showing 1 - 20 of 58

A new analysis of astrophysical S-factor from the experimental data
AMAR, A. ; BURTEBAYEV, N.
Measurements of the 6Li(p,)7Be reaction -ray angular distributions have been done at beam energies of Ep, lab. = 387, 690, 984 and 1283 keV for the -ray transitions to the ground and first excited (1/2-, 429 keV) states in 7Be. cross section of the 6Li (p, y)7Be reaction was calculated in the framework of the direct capture in the potential model using Fresco program. Spectroscopic factors of 7Be and astrophysical S-factor 6Li+p→7Be+y have been extracted from the experimental data available.
A Retrospective Study for Total Effective Doses of Nuclear Medicine Employees in Istanbul, Turkey
ÇAVDAR, İ.; USLU, L.; YEYİN, N.; DEMİR, M.
Thermoluminescence dosimeters (TLDs) are safely used to determine radiation doses. This study describes the radiation exposure doses of the radiation employees working at the Department of Nuclear Medicine, Cerrahpasa Medical Faculty in Turkey, where both radionuclide treatment and diagnostic imaging are done at a large scale. According to our results, the average effective dose value over five years belonging to an employee who works at radionuclide treatment service was found to have the highest value as 3.58±1.60 mSv. On the other hand, the average effective dose over a of total 29 employees is 1.53±0.59 mSv. A 5-year average effective dose was found as 1.29 mSv for technicians and 2.38 mSv for nurses. These results demonstrated that the radiation doses received by the employees working in different units are considerably different from each other. However, the doses received by all the workers in these units are under the regulatory limit. In conclusion, homogenized dose distribution between employees can be achieved in case of job rotations in-between.According to our results, the average effective dose value over five years belonging to an employee who works at radionuclide treatment service was found to have the highest value as 3.58±1.60 mSv. On the other hand, the average effective dose over a of total 29 employees is 1.53±0.59 mSv. A 5-year average effective dose was found as 1.29 mSv for technicians and 2.38 mSv for nurses. These results demonstrated that the radiation doses received by the employees working in different units are considerably different from each other. However, the doses received by all the workers in these units are under the regulatory limit. In conclusion, homogenized dose distribution between employees can be achieved in case of job rotations in-between.
A study on estimation of electric quadrupole transition probability in nuclei
AKKOYUN, S.; BAYRAM, T. ; KARA, S.O.
The reduced electric quadrupole transition probability (B(E2)↑) between 0+ ground state and 2+ state in nuclei is an important quantity because it represents basic nuclear information on energies of low-lying levels in the nuclei. It provides knowledge about deformation of nuclei. In this study, the B(E2)↑ values of some even-even nuclei in 110 ≤ A ≤ 190 region have been estimated by using artificial neural network (ANN) method which is a non-linear approximator. The present study shows that ANN is found to be useful in order to predict B(E2)↑ values of eveneven nuclei in this region.
A Theoretical Analysis of Quasi-elastic Scattering of 7Li by 120Sn Using Various Nuclear Potentials
(Ankara : Ankara Üniversitesi, 2017) Aygün, Murat; Fen Fakültesi
The quasi-elastic scattering data of 7Li + 120Sn reaction at ELab = 19.5, 20.5, and 25.0 MeV incident energies have been reanalyzed within the framework of the optical model. In order to obtain the real potential, seven different nuclear potentials have been used. The imaginary potential has been assumed in Woods-Saxon form. The theoretical results have been compared with each other as well as the experimental data.
Analysis of Gas Breakdown and Electrostatic Simulation Characteristics of a Spherical Inertial Electrostatic Confinement Fusion Chamber (SIEC-K)
(Ankara Üniversitesi Nükleer Bilimler Enstitüsü, 2020-07) Fettahoğlu, Ateş; Elektronik Mühendisliği; Mühendislik Fakültesi
In this study, a spherical inertial electrostatic fusion (SIEC-K) chamber is designed, built and operated to analyze electrostatic characteristics and gas breakdown conditions. The fusion chamber consists of two spherical electrodes; where the anode is the outer chamber of the chamber made out of two aluminum hemispheres and the cathode is a combination of stainless-steel wires forming a cage like structure aligned within the center. Design considerations and processes are introduced as the execution of this technology sustains the fundamental grounds to understanding gas breakdown. The conditions for gas breakdown are that under a low pressure environment where a certain potential difference is created between two electrodes, a deep potential well will be formed within the cathode region. The gas filled in the chamber will be ionized and the nucleus of the atoms will be accelerated towards the negative potential well, creating gas breakdown. Considering that this study will not focus on nuclear fusion reactions, the main fuel source is chosen to be air and it is also very convenient to operate with. Electrostatic simulation was made to estimate the plasma region inside of the SIEC-K chamber and check if the proposed design is in accordance with the literature, which is to validate the formation of the potential well within the structure of the cathode. The pressurevoltage values within the range of hardware limitations (1-6 kV) for gas breakdown values are recorded and qualitatively compared to their corresponding values for linear Paschen’s gas breakdown voltage law. The main motivation behind this study is to uncover the basis of plasma characteristics of the SIEC-K Reactor for future studies.
Analysis of the institutional framework for radioactive waste management in Bangladesh
MOLLAH, A. S.; SATTAR, Sabiha; ALTAB HOSSAİN, M.; JAHANGİR, M. H.; SALAHUDDİN, A.Z. M.
Bangladesh utilizes radioactive materials and radiation sources for a wide variety of peaceful purposes in industry, medicine, agriculture, research and education. At present, Bangladesh does not have nuclear power plant (NPP), so that the radioactive waste is mainly coming from above mentioned fields. Although Bangladesh has quite good infrastructure for the management of present radioactive waste, it needs improvement especially for the disposal program of the existing and future radioactive waste. This improvement of infrastructure is an important factor for preparation of future nuclear power plant (NPP) operation. The framework for institutional radioactive waste management in Bangladesh has been analyzed in this study. The analysis has been done using several key factors based on policy and strategy, regulatory authorities and their regulations, implementing organizations, participation of stack-holders and financial system. By considering the international trends and the Bangladeshi program to utilize nuclear power, the institutional infrastructure of radioactive waste management needs to be improved. The NSRC Rule-97, for the future beneficence, will have to be revised by incorporating several missing key points on radioactive waste management such as definition of radioactive waste, classification of radioactive waste, exempt and clearance limit, storage and retrieval, NORM/TENORM waste, disposal of LILW/HLW and spent fuel.
Analytical Formulae to Calculate the Total Efficiency of an Arbitrarily Positioned Point Source by an Elliptical Cylindrical Detector
ABBAS, M. I.; HAMMOUD, S.; IBRAHIM, T.; SAKR, M.
In this paper, a direct analytical method is presented for calculating the absolute efficiency of an elliptical cylindrical detector in the case of an arbitrarily positioned (above the major axis a) point source. The absolute efficiency is required to determine the activity of an unknown radioactive source, taking into account the attenuation of the gamma-ray photons. The validity of the derived analytical expressions was successfully confirmed by the comparison with some published data.
Application of SPECT / BT Simulations on Dynamic Resources by the Gate Software Oncological Imaging
(Ankara Üniversitesi Nükleer Bilimler Enstitüsü, 2018) Aynacı, B.; Kuday, S.; Other; Other
Computerized tomography is a method of radiological diagnosis that allows us to arrive at a cross-sectional view of a region of the body under examination using X-rays. SPECT is a high-level 3D imaging of scintigraphy taken for the treatment of conditions such as radioactive materials, thyroid diseases, cancers, tumors, inflammatory diseases, etc. The fact that SPECT and CT are in one system gives spatial and pathological correlation of abnormal metabolic activity. This ensures that images are recorded together at the most efficient level and images are obtained from both systems with a single review. In this study, SPECT / CT simulations were performed for cylindrical voxel phantoms with near-real content using the GATE (PET & SPECT simulator library) created by the GEANT4 simulation software developed by the European Center for Nuclear Research (CERN). In the installations created in the virtual environment, activity differences, displacement and curtain effects of the tissues were investigated. Analyses were made with the ROOT software to obtain sinograms and dose curves. When the obtained data were analysed statistically, the results of these types of SPECT / CT imaging were found to be significant differences and the results were revealed.
Assessment of Gama Dose Rates around Gaziantep City, Turkey
(Ankara : Ankara Üniversitesi, 2017) Zuhur, S.; Çeliktürk, D.; Yazıcı, A. N.; Öztürk, Z.; Fen Fakültesi
In this study, the measurements were performed 1 m above the ground in air and surface soils at certain points in the city of Gaziantep located at south of Turkey with a populatıon of 1.5 million. Air and soil measurements were carried out by portable detectors and gamma spectrometry system. As a result of measurements performed in the air, average annual effective dose of 66.81 µSv y-1 and gamma counting of 50.43 1 s-1 were found. On the other hand, as a result of gamma spectrometric analyses in the surface soil samples, average activity concentrations of 226Ra, 232Th and 40K were found to be 28.92, 29.49 and 255.30 Bq kg-1, respectively. Calculated absorbed dose rate and annual effective dose values depending on the activity concentrations, were found to be 38.45 nGy h-1 and 47.17 µSv y-1. When the measured values are compared with UNSCEAR 2000 report’s worldwide average value, our result is slightly lower than these values.
Assessment of occupational exposure in non-medical facilities of Bangladesh
Nizam, QMR; Shill, S.; Haider, M.
The concern about occupational exposure is being increased by the worker and regulatory body day by day in Bangladesh. After establishment of Bangladesh Atomic Energy Regulatory Authority (BAERA) this type of study has been carried out extensively for creating database about the safety of occupational worker in different facilities. The present research work has been performed on major non-medical radiological facilities including nondestructive testing (NDT), nucleonic gauge and irradiation facilities. Among these facilities, the workers of Engineer Inspection Services, Bangladesh (EISB) received high radiation doses. The outcome of the present study also shows that the radiation workers of NDT facilities are exposed to more radiation than any other facilities. This is because they used to work with high activity radiation source at offsite area. Every NDT facility should be more equipped with radiation shielding and personal protective equipment. These data can be utilized by BAERA in future for further strengthening of radiation safety infrastructure for the concerned workers.
Assessment of regulatory requirements in diagnostic X-ray facilities in Bangladesh
AKTAR, A.; HAIDER, M.; ISLAM, S.M.
X-ray imaging is one of the very old powerful modalities of diagnostic procedures. Bangladesh has a history of over 80 years of using X-rays for medical diagnostic purposes. But many of the users do not have enough knowledge about the potential risks associated with ionizing radiation like X-ray. To create awareness on radiation safety, Bangladesh Government for the first time promulgated nuclear safety and radiation control (NSRC) act in 1993 and corresponding NSRC regulation in 1997. The purpose of the current study is to evaluate shielding structure of some diagnostic x-ray facilities in Jessore district of Bangladesh with respect to regulatory standards. Radiation dose levels are also measured at different points in order to investigate the shielding adequacy of the facility. Estimated dose levels were found higher than the regulatory limit (0.5µSv/h) across the entrance door (ED) of 66% facilities. Secondary walls of the X-ray room were found adequately shielded with 10 inch brick wall. The shielding structure of control panel (CP) of the four facilities was not sufficient according to regulation and there was no shielding in the viewing window of CP of two facilities and the lead shielding thickness at the same points of two other facilities was found less than the regulatory requirement 2 mm lead thickness. Only 4 X-ray operators hold a qualified diploma as radiographer among 16 operators which could affect overall radiation safety features.
Assessment of the Effect of Breathing Movements on the Skin Dose by Comparison of TLD Measurements and Plan Data in Breast Cancer Radiotherapy
(Ankara Üniversitesi Nükleer Bilimler Enstitüsü, 2018) Ergün, D.; Arslan, S. Aytaç; Kaşkaş, A.; Other; Other
Breast cancer is the most common type of cancer in women. One out of every four women suffers from breast cancer in the world. İt is important for receiving adequate skin dose in breast cancer radiotherapy. The detailed information of dose in various depths of skin has a critical importance to determine new treatment techniques. If the skin dose homogeneity is not achieved, the risk of recurrence of disease is increased. Therefore, the homogeneity of dose distribution should be provided on the surface as it is in other parts of the breast. The aim of this study is to investigate the effect of respiratory movement and using the bolus on skin dose in breast cancer patients treated with helical tomotherapy. TLDs were placed on both the surface of the Alderson RANDO phantom's breast in eight points and on the projections of each points which is about 5 mm deep. A mechanism was used, which can be adjusted to the different frequency and amplitude values to simulate for measurements. The measurements were performed statically and dynamically (frequency=0.3 Hz, amplitude=5mm). Each measurement was repeated with and without bolus. The mean dose values were measured by using TLDs and bolus during respiratory at the surface and at 5 mm depth. The measured TLDs and calculated doses of TPS were compared, investigating the change of skin dose. The data were evaluated using the SPSS 20.0 statistical analysis program. According to the results, it is concluded that the respiratory movement is not a significant effect on the skin dose and it is not necessary to use the bolus. Besides, when TPS and TLD results were compared to each other; it is seen that, the estimation of skin dose of, TPS calculations was higher than TLDs measurements. This is clinically accepted. The results are in good agreement with literature values.
Calculation of double – differential cross sections for proton impact alpha emission at 62 MeV
SARPÜN, İ.H. ; ÜNAL, R. ; YALIM, H.A. ; AYDİN, A. ; KAPLAN, A.
This study reports on double–differential alpha emission cross sections for 16O, 27Al, 54,56Fe, 60Ni, 80Y, 120Sn, 197Au, 208Pb and 209Bi target nuclei with the TALYS code at 62 MeV proton energy. The calculations involved the pre-equilibrium exciton model and the Hauser-Feshbach model within TALYS code. The calculated results were compared with the experimental data taken from the literature. The results are in good agreement.
Calculation of neutron flux for the intense neutron source (µCF-INS) in optimum conditions
CHASHTI, M.; KALANTARI, S. Z.
In this study, the neutron spectrum of a high intense neutron source (µCF-INS) based on muon catalyzed fusion was investigated in new conditions. In order to determine optimum conditions for the production of high neutron flux with 14.1 MeV energy our study was grouped into three steps: the first includes the moderation µ- before entering into fuel mixture, the second is the calculation of neutron intensity produced by µCF cycle in D/T target and the third is simulation of output neutron flux from the device. The muon catalyzed fusion cycles were analyzed according to kinetic equations solved by Rung-Kutta method of the fourth order. Finally, transport of neutrons in DT mixture and its container was simulated by the MCNP4C code to calculate the output neutron intensity. The results show that the intensity of neutron produced by µCF-INS generator is in order of 1017 sn. When this result is compared with those from other neutron generators, µCF-INS generator operating at optimum conditions has a high neutron production yield.
Comparison of Surface Dose in Conventional and Digital Mammography and Forming the Statistical Mars Model for the Patients Who Had Mammography Examination in Compliance with the Mammography Examination Protocol
(Ankara Üniversitesi Nükleer Bilimler Enstitüsü, 2018) Kavas, Y.; Demir, P.; Akyol, M.; Ateş, A.; Other; Other
Digital mammography equipment in the 230 and 180 conventional mammography equipment were shooting from the upper breast and the inner surface of the patient. Conventional mammography shooting in 50 patients were measured from four different points outside the breast and bottom surfaces in addition to them. This method for TLD 100 dosimetric measurements were made using a dosimeter. A total of 460 patients compared the results obtained by conventional mammography, digital mammography in shooting with the dose received from the upper breast and the inner surface was determined to be higher in this study. As well as breast density values detected during breast ultrasound study of the patient's breast size, used during the measurement kVp and mAs values are also included in the study. This study attempted to establish Mars statistical model using all data obtained.
Destruction of DNA Through Ultraviolet Radiation (UV-C, UV-B, UVA-2, UVA1) in the Sterilization of Polymer Packaging (ISO: 1043 - PET, LDPE, HDPE) in Fermented Milk Products
(Ankara Üniversitesi Nükleer Bilimler Enstitüsü, 2019-07-11) Beluli, Valdrin; Kaso, A.; Fizik; Other
Recently UV radiation in the European Union (EU) is being used almost in many industrial aspects and is replacing chemical substances for sterilization. According to ISO 9001 standard, UV sterilization in polymers, being used as packaging in the dairy industry in fermented products is necessary. UV-C radiation within the spectral region (200-280 nm) is the most suitable for creating DNA defects for the purpose of destruction of hydrogen bond and amine bond between pyrimidine bases and the formation of highly stable covalent bonds in DNA. The quality of food products is one of the biggest challenges in food technology. Researchers have been researching in this field to provide a higher quality to food products in the sterilization of packaging (PET, LDPE, HDPE) from microorganisms, according to ISO1043. During this research it is found that the combination of ultraviolet (UV) and hydrogen peroxide (H2O2) are the strongest guarantors in the destruction of microorganisms and the formation of major defect in DNA.
Determination of natural radioactivity levels in Kars- city center, Turkey
CENGİZ, G. B.; REŞİTOĞLU, S.
The objective of this study is to determine the distribution of natural radionuclides in surface soils in the Karscity center, Turkey. The activity concentrations of 238U, 232 Th, 40 K and 137Cs in 38 soil samples collected from the study area were measured through NaI(Tl) gamma spectrometry. The average activities of the samples were determined to be 47.8, 31.2 and 536 Bqkg-1 for the natural radionuclides 226Ra (238U), 232Th, 40K, respectively, and 18 Bqkg-1 for the fission product 137Cs. When the present results are compared with the data available for other cities in Turkey, the soil radioactivity concentrations obtained in this study indicate that the region has a background radiation level within natural limits but the measured average activity of 40K depending on soil texture is slightly higher than the other parts of country.
Determination of the Mass Attenuation Coefficient, Effective Atomic Number and Electron Density for Manganese Nano Hydroxyapatite by using 778-1457 keV Gamma Rays
(Ankara : Ankara Üniversitesi, 2018) Koksal, O. K.; Cengiz, E.; Apaydın, G.; Tozar, A.; Karahan, İ. H.; Fen Fakültesi
In this study, manganese nano substituted hydroxyapatite artificial bone powders (nMnHAp) have been investigated experimentally by means of mass attenuation coefficients, effective atomic numbers and electron densities. The samples were irradiated using 778 keV, 964 keV, 1085 keV, 1112 keV, 1408 keV and 1457 keV gamma photons from 152Eu source .The gamma photons from the source were counted by using a HPGe gamma-ray spectroscopy. The mass attenuation coefficients of the hydroxyapatites artificial bone powders (including hydroxyapatite without any substituted metal and real bone powder) were compared with each other. This study has been dealt with as a guide to medical field. Also the results have been evaluated in terms of the electron density and effective atomic number.
Determination of Total Gamma and Peak Efficiency of NaI (Tl) Detector
(Ankara Üniversitesi Nükleer Bilimler Enstitüsü, 2018) Güngür, D.; Kızılyer, N. Yavuzkanat; Yalçın, S.; Other; Other
NaI(Tl) detectors have high detection efficiency. NaI(Tl) is good at detecting low-level radiation sources. In this study, the total gamma and peak efficiency results of NaI (Tl) detector for both point and disk sources were investigated. Total efficiency peak obtained by Geant4-based Gate Simulation program consisted with the literature and the data obtained using the hybrid Monte Carlo method. Full energy peak and total efficiency were also compared with the experimental result.
Development of Attitude Scale for Nuclear Energy and Environmental Impacts: Stability and Reliability Study
(Ankara Üniversitesi Nükleer Bilimler Enstitüsü, 2018) Güney, A.; Kaya, B.; Other; Other
This study, an attitude scale on the environmental effects of nuclear energy was developed. University students have been tried to determine their views on nuclear energy and environmental effects. The developed scale is a 5 point likert type attitude scale. Factor analysis was performed on the scale after the development phase of the scale and an adaptation model study was carried out on the scale items and dimensions. The scale was formed as a 37-item draft scale and 366 students were applied. In addition, students' relations with each other in terms of various variables have been examined. Within the scope of attitude scale reliability and reliability studies for nuclear energy and environmental effects, Cronbach Alpha reliability coefficient before analysis for general reliability was calculated as 0.534. When this value is small, a substance is removed from the scale (item 6) and the Cronbach Alpha reliability coefficient is calculated again. After analysis, it is calculated as 0,600. The results were evaluated at 95% confidence level.

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