Ferdi Akman

In the field of dentistry, the utilization of dental X-rays plays a pivotal role in ensuring accurate diagnoses for various dental conditions. A crucial aspect of this practice involves understanding how these X-ray emissions interact with dental braces. In the presented study, the details of how X-rays and gamma rays interact with different materials used in dental braces, namely stainless steel, nitinol, elgiloy, and beta-titanium alloys, were examined. This investigation was carried out through a combination of advanced simulation codes such as FLUKA and GEANT4, alongside theoretical calculations using the WinXCOM approach. A comprehensive analysis was conducted at fourteen distinct energy levels, ranging from 20 to 150 keV with 10 keV increments. The primary focus of this study revolves around quantifying the shielding characteristics of gamma and X rays as they traverse through these dental brace materials …

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 attenuation 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 capabilities 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 …

This study aimed to investigate the effect of diabetes on radiation attenuation parameters of the femur and tibia of rats using Monte Carlo Simulations. First, control and diabetic rats were identified and tibias and femurs were removed. Then, the elemental ratios of the bones obtained were calculated using EDS (Energy Dissipative X-ray Spectroscopy). Therefore, radiation permeability properties of control and diabetic bones were simulated by using the content ratios in the bones in MCNP6 (Monte Carlo N-Particle) and PHITS (Particle and Heavy Ion Transport code System) 3.22 and Stopping and Range of Ions in Matter (SRIM) simulation codes. Attenuation coefficient results were compared with the NIST database via XCOM. Although differences in absorption coefficients are observed at low energies, these differences disappear as the energy increases.

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 …

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 theoretical 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 …

This study delves into the potential of using tin oxide and cadmium oxide particles as fillers in dimethylpolysiloxane (silicone rubber) at weight fractions of 20% and 50%. The aim is to investigate the morphology and mechanical properties of the composites, as well as their ability to protect against gamma rays. To achieve this, a NaI(TI) detector was used to measure various protection parameters, including the linear attenuation coefficient (LAC), half-value layer (HVL), tenth-value layer (TVL), and effective atomic number (Zeff). The experimental mass attenuation coefficient (MAC) results were then compared with theoretical XCOM data. Moreover, the exposure buildup factor of metal oxide/silicone rubber composites was studied in the gamma-ray energy region of (0.015–15) MeV at different mean free path values. These comprehensive tests provide valuable insights into the performance and effectiveness of these …

Preventing people and electronic apparatuses from high-energetic nuclear radiation photons has been a significant concern. Due to disadvantages of lead, many studies have been carried out on different materials for several decades. The purpose of this investigation is to exhibit a novel shield design of alloys formed by the combination of W, La and Bi contents as a desired replacement for conventional lead-based absorbers. Photon shielding performances of the investigated alloys have been studied by estimation of mass attenuation coefficient, half-value layer by applying Monte Carlo GEANT4 simulation code and XCOM computer software. Moreover, the EBFs of the alloys were calculated by geometric progression (G-P) fitting formula for photon energy 0.015–10 MeV up to 40 mfp penetration depth. Consequently, the shielding performance of W-3 alloy shows that it is better by a factor of 1.52 and 8.29 than Pb …

The aim of this study is to evaluate gamma ray shielding properties for bismuth doped barite-based ternary polymer composite materials. In the first stage of the study, a polymer matrix was prepared by combining orthophthalic unsaturated polyester resin (OUP), Methyl Ethyl Ketone Peroxide (MEKP) and Cobalt Octoate (6%) (Co-6). Then, barite and bismuth were added in certain proportions as filler material into this polymer matrix and thus ternary composites were produced. Experimental studies for the produced samples were carried out in narrow beam geometry using HPGe detector and 133Ba, 22Na, 137Cs, 60Co radioactive sources which emit photons between 276.4 and 1332.5 keV energy. To determine the gamma ray shielding properties of the produced ternary composites, radiation protection efficiency (RPE), linear attenuation coefficient (μ), mass attenuation coefficient (μ/ρ), half value layer (HVL), tenth …

In the last few decades, the challenges of ionizing radiationIonizing radiationshieldingRadiation shielding have begun gaining attention of investigators in order to minimize the harmful effectsHarmful effects of various radiations especially on workers who are interested in the outcome of a nuclearNuclear or radiologicalRadiological situation that requires protectionProtection. In this context, the presented chapter focuses on the shieldingShielding preparation, materials designMaterials design, photonPhoton, and neutron shieldingNeutron shieldingperformancesPerformanceof polymer-based compositesPolymer-based composite doped with bismuth nitrateBismuth nitrate in different weight ratiosWeight ratio. Here, the photon attenuationPhoton attenuation behavior of the prepared compositesComposite is determined using a gamma spectrometerGamma spectrometer equipped with High Purity Germanium (HPGe …

In this study, radiation protection efficiency (RPE) for the coded as UP-Ba0, UP-Ba25, UP-Ba50, UP-Ba75 and UP-Ba100 at different sample thicknesses, total mass attenuation coefficient (μ/ρ), linear attenuation coefficients (μ), half value layers (HVL), tenth value layers (TVL), mean free paths (MFP), effective atomic numbers (Zeff) and effective electron densities (NE) were determined at various gamma energies between 59.5 and 1408.0 keV. With the help of the geometric progression (G-P) fitting method, the energy absorption build-up factor (EABF) and exposure build-up factor (EBF) values were calculated in the energy range from 0.015 MeV to 15 MeV for the produced composites. HPGe detector and eight radioactive sources (241Am, 152Eu, 137Cs, 133Ba, 60Co, 57Co, 54Mn and 22Na) were utilized in the experiment. Experimental results were compared with theoretical calculations and it has been observed …

This work presents a detailed radiation shielding study for polymer composites filled with Boron and Molybdenum 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, simulation, 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 …

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 …

Kα, Kβ and total K X-ray fluorescence cross-sections, K shell fluorescence yields, Kβ/Kα X-ray intensity ratios, K shell level widths, K shell life times, K to L shell vacancy transfer probabilities, K shell jump ratios, Auger electrons emission ratios and excitation factors for some elements in the atomic number range 22 ≤ Z ≤ 48 have been investigated. A Si(Li) detector and Am-241 annular radioactive source were used in the measurements. The obtained experimental data were crosschecked with theoretically calculated results and other available experimental results from the literature. It was observed that there is a good agreement between them within experimental uncertainties.

The aim of present investigation is to fabricate TiO2 reinforced novel composites as an alternate nuclear radiation shields. Unsaturated polyester resin has been reinforced by the incorporation of different weight proportions of titanium dioxide (5, 10, 15 and 20 wt%) nanoparticles. Accordingly, mass and linear attenuation coefficients (μm & μ), half and tenth value layers (HVL & TVL), relaxation length (λ) and effective atomic numbers (Zeff) have been computed. Gamma ray transmission set up has been employed for the determination of experimental μm values and consistency of experimental outcomes has been compared with the induced results from WinXCom program and Geant4 simulation code. Moreover, discrepancy of fast neutron removal cross section with the increasing TiO2 content in the prepared composites has been studied. Additionally, structural properties in terms of XRD, SEM, RAMAN, FTIR and …

In this study, inorganic compound (Bi2(WO4)3) was added into the composite to improve the radiation shielding properties of polymer composite. A polymer matrix was prepared by combining unsaturated polyester resin with methyl ethyl ketone peroxide and cobalt octoate (6%), and Bi2(WO4)3 was added to this polymer matrix at different ratios as filling material. In order to investigate the gamma radiation attenuation properties of the obtained polymer composites, mass attenuation coefficients, radiation shielding efficiencies, radiation transmission factors, linear attenuation coefficients, half values layer, tenth values layer, mean free path values, effective atomic numbers and effective electron densities parameters were obtained. Experimental studies were carried out with the help of HPGe detector at 22 different energies emitted from 22Na, 54Mn, 57Co, 60Co, 133Ba, 137Cs, 152Eu and 241Am radioactive sources …

In this study, the gamma radiation shielding characteristics of metallic glasses having Fe81B13.5Si3.5C2, Fe79B16Si5, Fe78B13Si9 and Fe40Ni38B18Mo4 components and coded as FeBSiC, FeBSi1, FeBSi2 and FeNiBMo were investigated. In order to investigate, the mass attenuation coefficients for metallic glasses in the photon energies range of 0.060 to 2.614 MeV were calculated with the help of WinXCOM program and GEANT4 and FLUKA simulation codes. The linear attenuation coefficient, half and tenth value layers, mean free path, effective atomic number and electron density parameters were calculated with the help of the calculated mass attenuation coefficients. Variations of the calculated gamma radiation shielding parameters with photon energy were discussed. It was observed that mass and linear attenuation coefficients, effective atomic number and electron density parameters decreased with increasing photon energy, while half and tenth value layers and mean free path parameters increased with increasing photon energy. It has been observed that metallic glasses have better gamma shielding capabilities in the low photon energy region, and metallic glass coded as FeNiBMo has better gamma radiation shielding capacity than other studied metallic glasses.

Ferrites are ceramic oxide materials consisting of mainly iron oxide and they have become massively important materials commercially and technologically, having a multitude of uses and applications. The protection against neutron–gamma mixed radiation is crucial in several nuclear applications. From this standpoint, mass attenuation coefficient, radiation protection efficiency and transmission factor of some ferrites namely barium, strontium, manganese, copper and cadmium ferrite has been computed using Geant4 and FLUKA simulations. Based on the simulated mass attenuation coefficient, other significant parameters such as linear attenuation coefficient, effective atomic and electron number, conductivity, half value layer, and mean free path were calculated for the selected ferrite materials. The validation of Monte Carlo geometry has been provided by comparing the mass attenuation coefficient results with …

Different types of photon shielding parameters such as total mass attenuation coefficient (μ/ρ), linear attenuation coefficients (μ), half value layers (HVL), mean free paths (MFP), effective atomic numbers (ZEff), energy absorption build-up factors (EABF), exposure build-up factors (EBF) and kerma relative to air were investigated for the fabricated Cu–Ag based alloys. The considered parameters were measured through gamma spectrometer equipped with HPGe detector in order to obtain the experimental attenuation coefficients and other related parameters at various photon energy in the energy range 59.5–1332.5 keV. The measured μ/ρ values were confirmed with WinXCOM database results. FLUKA and GEANT4 simulation codes were used to examine the compatibility of the experimental and WinXCOM database results with these simulation codes. The exposure buildup factors of the alloy samples were …

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 …

Advanced radiation applications have been widely used and extended to many fields. As a result of this fact, choosing an appropriate shielding material based on the radiation application has become vital. In this regard, the integration of elements into polymer composites has been investigated and contributed to the quantity and quality of radiation shielding materials. This study reports photon attenuation parameters and electromagnetic shielding effectiveness of a novel polymer composite prepared with a matrix reinforced with three different proportions (5, 10, and 15 wt%) of niobium content. Addition of Nb dopant improves both photon attenuation and electromagnetic shielding effectiveness for the investigated composites. Therefore, Nb(15%) polymer composite with highest concentration has been found to be the best absorber for ionizing and non-ionizing radiations. Consequently, the performed analyzes …