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Öğe A comparative neutron and gamma-ray radiation shielding investigation of molybdenum and boron filled polymer composites(Pergamon-Elsevier Science Ltd, 2023) Ogul, H.; Agar, O.; Bulut, F.; Kacal, M. R.; Dilsiz, K.; Polat, H.; Akman, F.This work presents a detailed radiation shielding study for polymer composites filled with Boron and Molyb-denum additives. The chosen novel polymer composites were produced at different percentages of the additive materials to provide a proper evaluation of their neutron and gamma-ray attenuation abilities. The effect of additive particle size on the shielding characteristics was further investigated. On the gamma-ray side, simula-tion, theoretical and experimental evaluations were performed in a wide range of photon energies varying from 59.5 keV to 1332.5 keV with help of MC simulations (GEANT4 and FLUKA), WinXCOM code, a High Purity Germanium Detector, respectively. A remarkable consistency was reported between them. On the neutron shielding side, the prepared samples produced with nano and micron particle size additives were additionally examined by providing fast neutron removal cross-section (sigma R) and the simulated neutron transmissions through the prepared samples. The samples filled with nano sized particles show better shielding capability than the one filled with micron sized particles. In other words, a new polymer shielding material that does not contain toxic content is introduced: the sample codded N-B0Mo50 exhibits superior radiation attenuation.Öğe A detailed investigation of gamma and neutron shielding capabilities of ternary composites doped with polyacrylonitrile and gadolinium (III) sulfate(Pergamon-Elsevier Science Ltd, 2023) Erkoyuncu, I. .; Akman, F.; Ogul, H.; Kacal, M. R.; Polat, H.; Demirkol, I.; Dilsiz, K.The shielding efficiencies of gamma and neutron radiations for ternary composites containing polyester resin, polyacrylonitrile and gadolinium (III) sulfate at different ratios were investigated in the present study. In order to investigate the gamma radiation shielding capacity of the produced ternary composites, linear and mass atten-uation coefficients, half value layer, effective atomic number and radiation protection efficiency parameters were determined experimentally, theoretically and using the GEANT4 simulation code. The gamma shielding capa-bilities of the composites were studied in the photon energy range of 59.5-1332.5 keV. In order to investigate the neutron shielding abilities of composites, inelastic, elastic, capture and transport numbers, total macroscopic cross section and mean free path parameters were determined with the help of GEANT4 simulation code. In addition, the number of transmitted neutrons at different sample thicknesses and neutron energies were also determined. It was observed that gamma radiation shielding properties were improved due to the increasing amount of gadolinium (III) sulfate and neutron shielding properties were improved due to the increasing amount of polyacrylonitrile. While the composite coded P0Gd50 exhibits a better gamma radiation shielding ability than the others, the neutron shielding of the sample coded P50Gd0 is also more favorable than the others.Öğe A study on photon/neutron interaction parameters with some alloys implant frequently used in orthopedics(Pergamon-Elsevier Science Ltd, 2025) Akman, F.; Turhan, M. F.; Ogul, H.; Ozdogan, H.; Turhan, M. K.Some Ti and Co-based alloys are used for implant purposes in orthopedics. These implants may cause artifacts during imaging in radiology. These may cause image quality to deteriorate due to glare in the relevant area. In the presented study, radiation protection efficiency (RPE), mass attenuation coefficient (mu/rho, MAC), linear attenuation coefficient (mu, LAC), half value layer (HVL), mean free path (MFP), tenth value layer (TVL), effective atomic number (Zeff) at 30-150 keV, energy-absorption build-up factor (EABF) and exposure build-up factor (EBF) at 0.015-15 MeV and kerma relative to air parameters at 0.001-20 MeV were obtained for some Ti and Cobased alloys, which frequently used in orthopedics. Photon interaction parameters were calculated using WinXCOM, MCNP6, PHITS, FLUKA and GEANT4 methods. EABF, EBF and kerma relative to air parameters were investigated theoretically with the help of WinXCOM. In addition, to investigate the neutron interaction parameters of these implants, RPE values at different thicknesses at 4.5 MeV with FLUKA, total macroscopic cross section and mean free path with GEANT4 and effective removal cross section for fast neutron with theory were obtained. Mass attenuation coefficients for the Ti-based alloys and Co-based alloys were determined as in the range from 0.159 cm2 g- 1 to 6.466 cm2 g- 1 and 0.200 cm2 g- 1 to 10.791 cm2 g- 1 in the energy range from 30 keV to 150 keV, respectively. It has been observed that among TiAl6V, Ti6Al7Nb, Grade1, Co28Cr6Mo, Co20Cr15W10Ni and Co35Ni20Cr10Mo implants, Co20Cr15W10Ni has the best attenuation ability for photons and neutrons.Öğe A study on radiation shielding properties, secondary radiation and radiation damage for composites containing glass fiber/PEEK/ gadolinium oxide(Pergamon-Elsevier Science Ltd, 2026) Erkoyuncu, I.; Maroc, F. Z.; Yilmaz, M.; Torun, T. R.; Ozdemir, H. G.; Ogul, H.; Akman, F.This study aimed to determine the gamma and neutron shielding capacities, the number of secondary gamma and neutrons produced after the primary neutron interaction together with their average energies and the damage caused by the incident gamma and neutron radiation on the composite for the composites containing glass fiber, PEEK and gadolinium oxide (Gd2O3). The theoretical approaches and/or simulation codes such as GEEANT4/FLUKA were used to determine these properties. It was observed that the gamma shielding capacity was improved for the studied composites with increasing Gd2O3 content. It was determined that the composite containing 50 % Gd2O3 (50GF50GdO), which was the highest studied amount, was superior to the others. The same composite also exhibited superior performance in removing fast neutrons. In addition, this composite has a fast neutron removal capacity that is 0.79 times higher than paraffin and 1.77 times higher than ordinary concrete. In terms of neutron shielding, the composite containing 50 % PEEK showed better performance at low energies, while 50GF50GdO replaced with this composite at high energies. It was determined that the composite coded as 50GF50GdO was less risky than the other composites in terms of both secondary gamma and secondary neutron formation. Finally, it was observed that as the energy of both gamma and neutron radiation increased, the studied composites were exposed to more radiation damage.Öğe Assessment of neutron and gamma-ray shielding characteristics in ternary composites: Experimental analysis and Monte Carlo simulations(Pergamon-Elsevier Science Ltd, 2024) Akman, F.; Kilicoglu, O.; Ogul, H.; Ozdogan, H.; Kacal, M. R.; Polat, H.The research aims to exploring the gamma -ray shielding capacities of polyacrylonitrile/chrome-filled polymer composites through a combination of experimental, theoretical and simulation methods. Additionally, employing MCNPv6 and GEANT4 simulation tools, the study evaluates the materials' performance against neutron radiation. The materials were subjected to various gamma -ray energy levels, and their shielding efficacies are analytically quantified using parameters such as Radiation Protection Efficiency (RPE), Mass Attenuation Coefficient (MAC), Linear Attenuation Coefficient (LAC), and Half -Value Layer (HVL). At various neutron energies and sample thicknesses, the numbers of transmitted neutrons were evaluated. Notably, composite P0Cr50 (not contain polyacrylonitrile and containing 50% chromium) emerges prominently, demonstrating superior radiation shielding characteristics against both gamma and neutron radiations. This attitude is attributed to its optimal chrome dispersion and density, positioning it as a promising candidate for radiation shielding applications in industrial and nuclear domains.Öğe Characterization of aluminum 8-hydroxyquinoline microbelts and microdots, and photodiode applications(Pergamon-Elsevier Science Ltd, 2020) Sevgili, O.; Canli, S.; Akman, F.; Orak, I; Karabulut, A.; Yildirim, N.In the present study, we investigated the electrical, optical, and photoresponse characteristics of aluminum 8-hydroxyquinoline (Alq3)/silicon heterojunctions. The Alq3 thin film was successfully coated using the spin coating method on p-type Si. In order to determine the energy band gap diagram, the highest occupied molecular orbital-lowest unoccupied molecular orbital energy diagram was simulated with the density functional theory program. The quality of the coating and morphological properties of the Alq3 thin film were characterized using atomic force microscopy and scanning electron microscopy. The optical characteristics of the organic layer were investigated using ultraviolet-visible spectrophotometry. A reference diode was also fabricated with an Alq3/pSi photodiode to obtain a better understanding of the electrical and optical properties of the device. The photodiode and diode parameters comprising the saturation current, ideality factor, barrier height, short circuit current, open circuit voltage, fill factor, and power conversion efficiency were obtained from the current-voltage measurements. These measurements were performed in the dark and under different illumination conditions at room temperature. The experimental results showed that the properties of the photodiode device were improved by using organic Alq3 microdots, and thus the device may have optoelectronic and photovoltaic applications.Öğe Determination of neutron and gamma ray shielding properties, secondary radiation formations and neutron damage of composites containing polyester/pyrite/titanium diboride(Pergamon-Elsevier Science Ltd, 2025) Turhan, M. F.; Kacal, M. R.; Ozdogan, H.; Tursucu, A.; Akman, F.; Ogul, H.; Polat, H.Composite materials comprising titanium diboride (TiB2), unsaturated polyester resin, and pyrite (FeS2) at varying weight percentages were fabricated and evaluated for their interaction with neutron and gamma radiation. This study adopts a comprehensive methodology, combining theoretical calculations, experimental measurements, and Monte Carlo simulations using PHITS and MCNP6. A strong correlation was observed among experimental results, WinXCOM data, and simulation outputs, with discrepancies remaining within approximately 5 %. To assess neutron shielding performance, fast neutron removal cross sections and partial neutron transmission rates were determined for both fast and thermal neutron energies, as well as across varying sample thicknesses. Additionally, secondary radiation effects were analyzed by quantifying the number and average energy of secondary neutrons and gamma photons generated from interactions with thermal and fast neutrons. Radiation damage parameters, including Total Ionizing Dose (TID) and Displacement Per Atom (DPA), were also evaluated. Gamma-ray shielding performance was assessed through experimental measurements, theoretical models, and Monte Carlo simulations, focusing on key parameters such as mass attenuation coefficients, kerma relative to air and concrete, and buildup factors. Among the composites, the sample labeled FeSTiB-50 demonstrated superior fast neutron attenuation capability-outperforming conventional concrete and approaching the shielding efficiency of paraffin-while all composites exhibited excellent attenuation of thermal neutrons. Furthermore, the FeSTiB-50 composite generated secondary radiation with lower average energy compared to other samples. However, the gamma-ray shielding performance was found to decrease with increasing TiB2 content, indicating a trade-off between neutron and gamma shielding effectiveness.Öğe Experimental, simulation, and theoretical investigations of gamma and neutron shielding characteristics for reinforced with boron carbide and titanium oxide composites(Pergamon-Elsevier Science Ltd, 2025) Ozdogan, H.; Kacal, M. R.; Kilicoglu, O.; Polat, H.; Ogul, H.; Akman, F.This study investigates the radiation shielding properties of composites containing polyester resin, boron carbide and titanium oxide in varying proportions. The radiation transmittance of the produced composites was measured using radioactive sources Am-241, Cs-137, Ba-133, Co-60, and Na-22 across a photon energy range of 59.5 keV-1332.5 keV. To analyze radiation permeability, experimental geometry was simulated using Monte Carlo-based computer codes Monte Carlo N-Particle (MCNP), Particle and Heavy Ion Transport code System (PHITS) and FLUktuierende KAskade or Fluctuating Cascade (FLUKA), and the experimental data were compared with simulation results and theoretical data obtained from WINXCOM. The findings demonstrated a high degree of consistency between experimental, simulation, and theoretical results. Notably, the BCTiO50 sample, which included a 50% addition of TiO2, emerged as the most effective in photon radiation shielding. In addition to gamma shielding, the neutron shielding properties of the produced composites were evaluated using the FLUKA code, revealing that the BCTiO0 sample, with the highest percentage of boron, provided the best neutron shielding. This analysis included composites with decreasing boron carbide content by 10%, 20%, 30%, 40%, and 50% by weight, each replaced with titanium oxide, showcasing the potential applications of these polymer composites in radiation shielding.Öğe Gamma and Neutron Shielding Parameters of Polyester-based composites reinforced with boron and tin nanopowders(Pergamon-Elsevier Science Ltd, 2022) Ogul, H.; Polat, H.; Akman, F.; Kacal, M. R.; Dilsiz, K.; Bulut, F.; Agar, O.The usage of composites as the shielding materials are highly recommended since they could be used in order to attenuate the undesired radiation with unique properties and advantages in the areas where the radiation is prevalent. In this context, not only are their radiation shielding properties important but also their flexibility, durability and low cost. Due to the mentioned superior characteristics, the polyester based composites are among the most preferred materials. With the aim of creating unique and novel radiation shielding materials, this study investigates gamma and neutron shielding capabilities of the polyester composites reinforced with Boron and Tin nanopowders at different proportions (0-50%, 10-40%, 20-30%, 30-20% and 40-10%, 50-0%). The gamma shielding abilities of the prepared polyester composite materials were evaluated using an HPGe detector system, WinXCOM computer program and different simulation tools (FLUKA and GEANT4) at the energies varying from 59.5 to 1332.5 keV. The experimental, theoretical and simulation results showed remarkable agreement between each other, and the addition of Sn enhances the gamma attenuation performance of the chosen polyester composite materials. In addition to gamma analysis results, neutron shielding properties of the proposed com-posites are further determined. On this purpose, the transmitted neutron numbers through the samples (as functions of neutron energy and the sample thickness) and effective neutron removal cross sections were eval-uated. The neutron shielding performance of the samples showed that the prepared composites could be alter-native materials to the existing neutron shields in the literature.Öğe Gamma attenuation characteristics of CdTe-Doped polyester composites(Pergamon-Elsevier Science Ltd, 2021) Akman, F.; Ogul, H.; Kacal, M. R.; Polat, H.; Dilsiz, K.; Agar, O.Polyester is strong and durable material and tends to retain its shape, thus polyester composites have become highly preferred option in high-tech applications. This motivates the usage of polyester composites in the production of radiation shielding materials as well. In present study, gamma ray shielding properties of polyester composite reinforced with different proportions of Cadmium Telluride (5%, 10%, 15% and 20%) have been investigated theoretically and experimentally. The experiments were performed with the use of HPGe detector in a wide range of photon energies varying from 59.5 to 1408.0 keV while XCOM computer program was computed in the same photon energy range to obtain theoretical results and to verify the experimental outcomes. Remarkable radiation protection efficiency was obtained with additive material of Cadmium Telluride, and the radiation protection efficiency was found to be increased with the increase of additive material amount. Negligible discrepancies between experimental and theoretical results were also observed.Öğe Gamma, charged particle and neutron radiation shielding capacities of ternary composites having polyester/barite/tungsten boride(Pergamon-Elsevier Science Ltd, 2023) Akman, F.; Ozdogan, H.; Kilicoglu, O.; Ogul, H.; Agar, O.; Kacal, M. R.; Polat, H.The presented work investigates the photon, charged particle and neutron radiation shielding performances of polyester-based composites filled with barite and/or tungsten boride by using experimental, theoretical, and Monte Carlo simulation techniques. The amount of barite/tungsten boride varying from 0 wt% to 50 wt% in the material and polyester resin were exploited as filler and base materials, respectively. Experimental evaluation of BaWB composites has been performed with help of an HPGe detector based gamma spectrometer as well as 22Na, 133Ba, 137Cs and 60Co radioactive point sources with energies in the range of 276.4-1332.5 keV. The experimental data were compared to those theoretically calculated in WinXCOM as well as Monte Carlo (MC) simulations, i.e., MCNP6, GEANT4 and FLUKA codes. The obtained mass attenuation coefficients for the produced composites were in good agreement with the results of MC simulations and WinXCOM software. Comparing to the other polymer composite samples, the sample with the maximum tungsten boride weight percentage has the best radiation shielding property because of having the highest attenuation coefficients and lowest absorption thicknesses.Öğe Impact of lead(II) iodide on radiation shielding properties of polyester composites(Springer Heidelberg, 2020) Akman, F.; Ogul, H.; Kacal, M. R.; Polat, H.; Dilsiz, K.; Turhan, M. F.This paper investigates the radiation shielding properties, such as linear and mass attenuation coefficients, half and tenth value layers, effective atomic number and electron density, and radiation protection efficiency as a function of photon energy, of a new composite, PbI2-doped polyester. The mentioned polyester composite was prepared with different proportions of lead(II) iodide (5% increments between 5 and 20%) so that impact of the dopant amount on radiation shielding could be properly analyzed. The prepared composites were tested in 22 different energies in the energy range of 59.5-1408.0 keV with the use of HPGe detector and eight radioactive point sources. The obtained results were further validated by comparing the results of XCOM computer program, and negligible discrepancies were observed. It was observed that PbI2 (20%) composite is more effective gamma radiation shielding material than other produced composites. In light of this information, it can be said that the shielding efficiency increases with increasing lead(II) iodide amount.Öğe Micro Pb filled polymer composites: Theoretical, experimental and simulation results for γ-ray shielding performance(Pergamon-Elsevier Science Ltd, 2022) Kilicoglu, O.; V. More, Chaitali; Akman, F.; Dilsiz, K.; Ogul, H.; Kacal, M. R.; Polat, H.Researches on advanced composites to protect environment health towards radioactive pollution have drawn attention with the rising use of radioactive elements. From this point, polymer micro composites are quite encouraging in terms of multifunctional properties in mechanical, electrical, thermal, as well as nuclear shielding. The present study has explored the efficacy of micro lead (Pb) loaded polymer composites for radio protective applications such as a fabrication of protective enclosures. High energetic photon shielding experiments have been applied through gamma spectrometer equipped with HPGe detector and various radioactive point sources namely 137Cs, 22Na, 152Eu, 133Ba, 241Am and 57,60Co which are widely used in several medical and industrial applications. The results demonstrated that mass attenuation coefficients of the composites at different photon energies are proportional to the filler loading. The validation of FLUKA and GEANT4 Monte Carlo software has been performed in the simulation of transmission experiments as well as WinXCOM software. The tests of the Pb (20%) micro composite for the nuclear radiation shielding reveal that it has high attenuation coefficients for photon radiation.Öğe Nuclear radiation shielding performance of borosilicate glasses: Numerical simulations and theoretical analyses(Pergamon-Elsevier Science Ltd, 2023) Kilicoglu, O.; Akman, F.; Ogul, H.; Agar, O.; Kara, U.The photon shielding performances of five different borosilicate-based glasses were investigated in this study using the FLUKA, GEANT4 and MATLAB codes, as well as the XCOM program, at photon energies ranging from 0.03 to 15 MeV. In this context, dependencies of the photon attenuation features with the variation of the photon energy and the chemical compositions have been carefully evaluated with Monte Carlo simulation and theo-retical evaluation tools. The mass attenuation coefficient values and effective atomic numbers obtained for BaO-doped G5 glasses are found to be higher than those derived for G1-G4 samples. In other words, the Zeff results showed that high Z-elements such as Ba in a suitable amount should be inserted into the glass composition in order to improve the photon attenuation capability of the borosilicate glasses. The HVLs, TVLs, and MFPs of the studied borosilicate glasses are determined further, and the gamma shielding characteristics of the analyzed samples are found to be associated to the density of the glass, implying that high-density glass can be used for high-level attenuation performance. The exposure buildup factor (EBF) values have been further estimated via the G-P fitting approach. The results of such investigations, according to the work given, may be valuable in designing and fabricating new borosilicate-based glasses, which can then shield against potential radiation damage to environmental health.
