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Öğe Analyzing neutron and gamma ray shielding properties in varied W-B2O3 ratios: methodological comparisons and Monte Carlo simulation(Taylor & Francis Ltd, 2024) Yavuzkanat, Nuray; Sahmaran, TuranThis study aims to comprehensively assess the radiation shielding efficacy of W-B2O3 composite material across varying ratios, contrasting its performance with glass and established literature data. The investigation involves comparing the radiation shielding capabilities of these materials using Geant4-based GATE simulation, XCOM, and EpiXS programs across energy levels ranging from 0.3-2.516 MeV. The research involved calculating and comparing the effective removal cross-section values of these materials with those commonly employed in neutron shielding. The findings indicate superior radiation shielding capabilities in the composite material compared to glass. Moreover, the mass attenuation coefficients were derived through GATE simulation at energy levels of 6 and 18 MV mono and spectrum energy. These values were then compared with theoretical methods; XCOM, XMuDat, and an innovative methodology outlined in the current literature. In the new approach, the effective atomic numbers of the materials were determined using the mass attenuation coefficients.Öğe Chemical and physical analysis of synthesized coumarin compounds: Investigating responses to gamma and neutron radiations(Pergamon-Elsevier Science Ltd, 2024) Yavuzkanat, Nuray; Sahmaran, Turan; Sarac, KamuranThis research investigates the chemical and physical characteristics of three recently synthesized coumarin compounds produced via the von Pechmann condensation mechanism. These compounds were successfully and precisely synthesized, as confirmed by a comprehensive understanding of their chemical composition obtained through combined infrared and NMR analyses. The compounds underwent examination regarding their responses to gamma and neutron radiations, and their mass attenuation coefficients (MAC) were determined using both GATE/Geant4 simulation and NIST-XCOM data. Additionally, the effective removal cross-section values for fast neutrons were calculated employing various methods. All acquired data has been compared with that of water and other materials in the existing literature. Although coumarin compounds might not have intrinsic shielding properties, they have the potential to be part of composite materials designed for specific applications. Comparative analysis with established radiation dosimetry systems showed the coumarin compounds' attenuation coefficients closely aligning with water, indicating their potential suitability for nuclear applications requiring water -equivalent properties. Further assessment with Geant4 simulation under linac photon beams demonstrated the water -equivalent properties of the coumarin compounds for 6 MV and 18 MV.Öğe Determination of the radiological properties of materials: A new approximation method for calculation of the mass attenuation coefficients(Pergamon-Elsevier Science Ltd, 2022) Kaskas, Ayse; Sahmaran, TuranDosimetric measurements of the medical LINAC device using phantoms are an important procedure to determine the correct delivery dose on the target volume. The percentage depth dose values of RW3, SW557, ABS, epoxy, PRESAGE phantom materials obtained from a simulation program were compared with those experimentally measured with water phantom at 6 and 18 MV photon energy spectrums. The values of energy spectrums of photons were taken from the database of Elekta Synergy Linear Accelerator device and defined in GATE/Geant4 simulation program. The mean percentage dose differences for all these materials were compared with water phantom and the closest phantom material to water was determined as SW557 at 6 and 18 MV photon energies. The mass attenuation coefficients, the effective atomic numbers and electron densities of water-equivalent phantom materials and some selected human organs were found for both monoenergetic photons and 6, 18 MV photon energy spectrums using GATE simulation code. Furthermore, a new approximation method was developed to calculate the mass attenuation coefficient for the photon energy spectrums. There was determined to be good agreement between the numerical calculations of the approximation method and the simulation results, with a difference of less than 4% between them.Öğe Evaluation of dosimetric parameters after electron gun and ion pump replacement in linear accelerator device and comparison of results by gATE/Geant4 simulation(Taylor & Francis Ltd, 2023) Sahmaran, Turan; Koca, CeyranThis study evaluates dosimetric data such as PDD, dose profile and tissue phantom rate (TPR20/10) after replacing the LINAC device's electron gun and ion chamber pump. These values obtained after the change were compared with the standard PDD protocol, British Journal of Radiology Supplement 25 (BJR 25) report, Beam Data (measured and recorded as reference values during the setup phase, BD) and simulation results. In additional, uncertainty results were obtained for absorbed doses to water using different calculation tools. The experimental setup was created in the GATE/Geant4 simulation program, and the experimentally obtained TPR20/10, beam profile and PDD values were compared with the simulation. The difference between TPR20/10 values for 6 and 18 MV photon energies was found to be below 1% for 6 MVs and 3% for 18 MV. When different calculation tools were used, uncertainties were found in the absorbed dose measurements ranging between 0.8% and 1.87%, which is compatible with the uncertainties (1.4-2.1%) specified in the IAEA report. Even though small uncertainties were observed in the results, the differences between the calculations in the measurements of absorbed doses were insignificant. Estimated uncertainties for GATE was a little smaller than those measured using experimental methods, BD and BJR 25. Although the values obtained are within the tolerance, after such significant materials are changed in the LINAC device, a water phantom should be set up, the measurements should be repeated, and the results should be confirmed to be within the limit values.Öğe Evaluation of gamma and neutron radiation shielding parameters of some glass materials by monte corlo and theoretical method(Taylor & Francis Ltd, 2024) Sahmaran, Turan; Yavuzkanat, NurayThe present study investigates the gamma-ray and neutron shielding properties of PbCu3Ti4O12, lithium borate (Li2B4O7), lithium borate glasses doped with dolomite (CaMg(CO3)) and neodymium oxide (Nd2O3) to assess their effectiveness as shielding materials against ionizing radiation. The gamma-ray shielding properties, including the attenuation and absorption characteristics of the materials were examined and compared using Geant4-based GATE simulation, XCOM, and EpiXS in the photon energy range of 80-2000 keV. When the shielding properties of the available materials were compared, it was determined that Li2B4O7-Nd2O3, PbCu3Ti4O12, Li2B4O7-CaMg(CO3), and Li2B4O7 exhibited the best shielding properties, in order from most effective to least effective. The neutron shielding properties of these materials, including scattering, absorption, and moderation capabilities, were also determined using MRCsC, Phy-X/PSD and estimation sigma R/rho of elements. The results were then compared with the current literature. Li2B4O7, CaMg(CO3), and Nd2O3-doped lithium borate glass samples showed higher effective fast neutron removal cross-section values than water and concrete in all calculation methods. It shows that the investigated glass materials are better gamma and neutron beam absorbers and have the potential for use in gamma and neutron beam shielding applications.Öğe Evaluation of the radiological properties of gel dosimeters and some human tissues based on experimental water and Monte Carlo simulation results(Korean Physical Soc, 2023) Sahmaran, TuranThe aim of the present study is to obtain dose distributions of geldosimeters at 6 and 18 MV photon energies and 6, 9, 12, 15, and 18 MeV electron energies using the GATE simulation program and to compare the resulting radiological features with the results experimentally obtained for liquid water and the international dose protocol suggested by the IAEA. Furthermore, in this study, the fast neutron removal cross-sections (Sigma(R)) and attenuation lengths of gel dosimeters have been calculated. The effects on the absorbed dose distributions due to variation in the effective atomic number, mass attenuation coefficient, and effective photon energy are calculated for MAGIC, MAGAS, MAGAT, LMD1, LMD2, FAX, FXG, PAKAG formulations at irradiations with photon and electron beams. In the present study, mass attenuation coefficient values calculated for mono energies of 6 and 18 MV were compared with the values acquired by GATE, XCOM, PhyX-PSD, EpiXS, and XMuDat softwares for the same energies. In addition, spectrum values of the multi-energetic photon energies of 6 and 18 MV were drawn from the LINAC device database and introduced to GATE, and mass attenuation coefficient values of the gel dosimeters in the spectrum energy were calculated. In the 6 and 18 MV energy photon energy, MAGAS and FAX were found to have the lowest difference compared to water. Mean dose differences of MAGAS and FAX were obtained as 0.76 +/- 0.69 and 1.74 +/- 0.59, respectively. Mean dose differences of the gel dosimeters compared with water did not exceed 3% in both energy types. The study shows that, as a result of the simulation, software programs, the new approach, and theoretical calculations, it was found that the values obtained for ef fectiveatomicnumber and mass attenuation coefficient were compatible with liquid water.Öğe Exploring occupational radiation exposure: Insights from a decade-long study (2012-2021)(Elsevier, 2024) Sahmaran, Turan; Corapli, HaticeThis study was conducted at Hatay Mustafa Kemal University Tayfur Ata Sokmen Faculty of Medicine. The dose results of 899 radiation workers between 2012 and 2021 were examined. The aim of this study was to analyze the dose results of occupational radiation-exposed workers. Additionally, the lifetime excess cancer risk for radiation workers has been estimated. Radiation workers were divided into five categories: diagnostic radiology (DR), dental radiology (Dent), endoscopy (Endo), angiography (Ang), and operating room (OR). Average annual effective doses were obtained for each category. The highest exposure was recorded in diagnostic radiology workers, while the lowest exposure was observed in endoscopy workers. In this study, the annual average effective dose values for personnel exposed to radiation were calculated as 1.38 mSv, 0.97 mSv, 1.28 mSv, 1.48 mSv, and 1.44 mSv for DR, Dent, Endo, Ang, and OR, respectively. The projected cancer risk for DR, Dent, Endo, Ang, and OR between 2012 and 2021 is observed to be 7.09, 1.12, 0.95, 2.44, and 3.08 per million individuals respectively. According to the UNSCEAR 2000 report, worldwide average doses in diagnostic radiology and dental radiology were reported as 1.34 mSv and 0.89 mSv, respectively. The annual average effective doses were well below the permissible annual limit of 20 mSv.Öğe INVESTIGATION OF RADIOLOGICAL PROPERTIES OF IMAGING AGENTS USED IN NU CLEAR MED I CINE WITH DIF FER ENT METH ODS AND GATE/GEANT4 SIM U LA TION PRO GRAM(Vinca Inst Nuclear Sci, 2023) Sahmaran, Turan; Tugrul, TaylanThis study aims to determine the radiological properties of various radiopharmaceuticals used in nuclear medicine. In the study, mass attenuation coefficient values in different energy ranges were ob tained for six dif fer ent radiopharmaceuticals dimercaptosuccinic acid, diethylenetriamine pentaacetate, mercaptoacetyltriglycine, hexamethylpropyleneamine oxime, methoxyisobutylisonitrile, meth y lene diphosphate by us ing GATE sim u la tion pro gram, XCOM and WinXCom pro grams. Us ing these val ues, ef fec tive atomic num ber and elec tron den sity val ues were cal cu lated with the help of the di rect method, in ter po la tion method, Auto-Zeff soft ware, Phy-X/ZeXTra, XMuDat pro gram, and Mayneourd's for mula. In ad di tion, the ef fec tive atomic num ber and elec tron den sity val ues ob tained were com pared for each radiopharmaceutical, both among them selves and be tween the meth ods. When radiopharmaceuticals were com pared among them selves in low and high-en ergy re gions, the high est ef fec tive atomic num ber val ues were ob tained in dimercaptosuccinic acid, meth y lene diphosphate, and mercaptoacetyltriglycine. The mass attenuation coefficient values calculated us ing the GATE code in di cate that it is a suit able method for de ter min ing the mass at tenuation coefficient for imaging agents with no experimental values. This study indicates that the sim u la tion ge om e try method is suit able to be used as an al ter na tive method for the ex per i ments. In ad di tion, the val ues ob tained for these mol e cules used as radiopharmaceuticals were ex am ined for the first time.Öğe Least Significant Changes and Reproducibility of 131I Uptake Test(Lippincott Williams & Wilkins, 2021) Sahmaran, Turan; Gultekin, Salih SinanRadioactive iodine uptake (RAIU) is one of the important tests performed in the departments of nuclear medicine, testing thyroid function by measuring the amount of I-131 uptake after oral administration. A RAIU value measured 4 and 24 h after administration has been widely used for differential diagnosis of thyroid function and for the calculation of treatment dose. This study was performed to define practical methods for reproducibility and least significant change (LSC) values replicating thyroid measurements. In the study were 119 patients referred to the nuclear medicine department for examination of thyroid gland function with the diagnosis of Graves' disease (60), toxic multinodular goiter (29), thyroiditis (10), thyroid cancer (6), and unknown etiology (14). The level of thyroid stimulating hormone (TSH) among the patients was 2.07 +/- 6.74 mu IU mL(-1). RAIU measurements were carried out by two different technicians, who have performed an equal number of measurements from each diagnosis in reference to the clinical diagnosis. Measurement of each patient was performed twice at 4 and 24 h after the administration under stable geometry and counting conditions using a standard procedure. Data were evaluated using statistical methods. For assessment of the reproducibility, three parameters were used: reproducibility coefficient (RC), the root-mean-square standard deviation (SDRMS), and the least significant change values. The average RAIU values of the first and second measurements were found as 23.71 +/- 16.52% and 23.94 +/- 16.64% at 4 h (p >0.05), and 35.33 +/- 19.22% and 35.49 +/- 19.19% at 24 h (p >0.05), respectively. For thyroid uptake values repeated at 4 and 24 h after radioiodine administration, the mean difference was found to be -0.24 +/- 0.62% [limits of agreement (%); -1.44 to 0.97] at 4 h and -0.16 +/- 0.44% [limits of agreement (%); -1.02 to 0.70] at 24 h. Confidence intervals were within the limits of agreement (d-1.96 SD and d+1.96 SD). When the correlation between the repeated RAIU measurements was examined taking the differences and averages into account, there was a negative correlation between 4-h measurement pairs (r=-0.203, p <0.05). On the other hand, a significant correlation was not found between the 24-h measurement pairs (r=0.074, p >0.05). RC, SDRMS, and LSC were calculated as 0.70%, 0.46%, and 1.29% for the 4 h measurements and 0.54%, 0.33%, and 0.91% for the 24-h measurements, respectively. Although there was a minor difference between measurement pairs at 4 and 24 h post-administration, the difference appeared to be insignificant without an apparent effect in the clinical settings.
