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A closer look at the utilized radiation doses during computed tomography pulmonary angiography (CTPA) for COVID-19 patients
(Pergamon-Elsevier Science Ltd, 2023) Abuzaid, Mohamed; Elshami, Wiam; Cavli, Baris; Ozturk, Ceren; ALMisned, Ghada; Tekin, H. O.
Introduction: CTPA stands for computed tomography pulmonary angiography. CTPA is an X-ray imaging that combines X-rays and computer technology to create detailed images of the pulmonary arteries and veins in the lungs. This test diagnoses and monitors conditions like pulmonary embolism, arterial blockages, and hyper-tension. Coronavirus (COVID-19) has threatened world health over the last three years. The number of (CT) scans increased and played a vital role in diagnosing COVID-19 patients, including life-threatening pulmonary em-bolism (PE). This study aimed to assess the radiation dose resulted from CTPA for COVID-19 patients. Methods: Data were collected retrospectively from CTPA examinations on a single scanner in 84 symptomatic patients. The data collected included the dose length product (DLP), volumetric computed tomography dose index (CTDIvol), and size-specific dose estimate (SSDE). The organ dose and effective dose were estimated using VirtualDose software.Results: The study population included 84 patients, 52% male and 48% female, with an average age of 62. The average DLP, CTDIvol, and SSDE were 404.2 mGy cm, 13.5 mGy, and 11.6 mGy\, respectively. The mean effective doses (mSv) for males and females were 3.01 and 3.29, respectively. The maximum to minimum organ doses (mGy) between patients was 0.8 for the male bladder and 7.33 for the female lung.Conclusions: The increase in CT scans during the COVID-19 pandemic required close dose monitoring and optimization. The protocol used during CTPA should guarantee a minimum radiation dose with maximum pa -tient benefits.
A closer-look on W and Pb alloys: In-depth evaluation in elastic modulus, gamma-ray, and neutron attenuation for critical applications
(Elsevier Science Sa, 2024) Almisned, Ghada; Susoy, Gulfem; Sen Baykal, Duygu; Alkarrani, Hessa; Guler, Omer; Tekin, H. O.
This investigation assesses the gamma -ray and neutron attenuation properties of various alloys, including Pb90Cu10, A5, Manganin-R, Cu0.2Ag0.8, SA4, and W -based, to uncover efficient and cost-effective radiation shielding materials. Our study centers on alloys featuring elements such as lead, molybdenum, silver, and tungsten, selected for their unique protective qualities against radiation. Employing computational methods to evaluate critical parameters like mass attenuation coefficients, half -value layers, linear attenuation coefficients, and effective atomic numbers, transmission factor, we found the W -based alloy to exhibit exceptional shielding properties, primarily due to its tungsten content. Interestingly, this alloy also demonstrated the highest elastic modulus among the samples studied, indicating a potential synergy between an alloy's mechanical strength and its radiation shielding effectiveness. It can be concluded that alloys with higher elastic moduli not only offer better resistance to radiation -induced deformations, enhancing shielding, but also underscore the need for further research on alloys that balance performance, affordability, and environmental impact. The findings underscore the dual importance of composition and mechanical properties in advancing radiological safety and suggest continued investigation into the sustainability and practicality of effective shielding materials.
Designing a Lead-free and high-density glass for radiation facilities: Synthesis, physical, optical, structural, and experimental gamma-ray transmission properties of newly designed barium-borosilicate glass sample
(Elsevier Science Sa, 2023) Sen Baykal, Duygu; Kilic, G.; Ilik, Erkan; Kavaz, E.; ALMisned, Ghada; Cakirli, R. B.; Tekin, H. O.
We report the design, synthesis, optical, structural, and gamma-ray attenuation properties of a newly developed Lead-free and high-density borosilicate glass sample for its potential applications in medical and industrial ra-diation facilities. A barium-borosilicate glass sample (BSBaZn) was designed and synthesized using nominal composition of 7B2O3-50SiO2-38ZnO-5BaO. The FTIR spectrum of the BSBaZn is revealed four fundamental regions. These regions are 400-620 cm-1, 620-770 cm-1, 800-1210 cm-1, and 1210-1500 cm-1. Transmittance rate in the wavelength range of 350-1100 nm is reported as 80 %. A high-purity Germanium (HPGe) detector along with an energetic 133Ba radioisotope is also utilized for experimental gamma-ray transmission studies. Various fundamental gamma-ray shielding parameters of BSBaZn are determined and accordingly compared with many other glass shields. MCNPX (version 2.7.0) general purpose Monte Carlo code is utilized for gamma-ray transmission factor (TF) values. The results showed that the synthesized BSBaZn sample has promising struc-tural, optical, and physical properties in addition to promising gamma-ray attenuation properties. The high transparency of BSBaZn along with its high-density may be considered as an important selection criterion for its implementation in protection purposes in medical and industrial radiation facilities, where the source and pa-tients monitoring play a significant role.
Dual Impacts of Bi2O3/B2O3 Substitution on Mechanical and Attenuation Properties of Zinc-Bismuth-Borate Ternary Glasses for Diagnosis ?-Rays Shielding Materials Application
(Springer, 2023) Zakaly, Hesham M. H.; Tekin, H. O.; Issa, A. M. Shams; Alrowaily, Albandari W.; Ene, Antoaneta; Rammah, Y. S.
Investigations have been made on the mechanical and gamma-ray attenuation properties of the zinc bismuth-borate ternary glass system with the chemical formula (70-x)Bi2O3-xB(2)O(3)-30ZnO, where x = 20 (S1), 25 (S2), 30 (S3), 40 (S4), 45 (S5), and 50 (S6) mol%. Makishima-Mackenzie model and Phy-X/PSD software were used to accomplish this goal. Our research showed that the packing density (Vt) and dissociation energy (Gt) values reduced from S1 glass sample (with B2O3 = 20 mol% and Bi2O3 = 50 mol%) to S6 glass sample (with B2O3 = 50 mol% and Bi2O3 = 20 mol%), respectively, from 0.522 to 0.352 and from 31.53 kJ/cm(3) to 26.97 kJ/cm(3). By increasing the amount of B2O3 in the glasses, the efficiency of their mechanical features was reduced. The S1 glass sample's linear (mu) and mass attenuation (mu(m)) coefficients had the highest values among the glass materials examined, i.e., (mu, mu(m))(S6) < (mu, mu(m))(S5) < (mu, mu(m))(S4) < (mu, mu(m))(S3) < (mu, mu(m))(S2) < (mu, mu(m))(S1). The S1 glass sample exhibits the lowest values for half value layer (T-0.5) and mean free path (lambda) of all the examined glasses. Consequently, (T-0.5, lambda )(S6) > (T-0.5, lambda )(S5) > (T-0.5, lambda )(S4) > (T-0.5, lambda )(S3) > (T-0.5, lambda )(S2) > (T-0.5, lambda )(S1). The analyzed glasses' effective atomic numbers (Z(eff)) follow the same trend for mass and linear attenuation coefficients. Our results show that the values of exposure (EBF) and energy absorption (EABF) accumulation factors decreased with increasing Bi2O3 and lowering B2O3 reinforcement for all mean free path values (i.e., from 0.5 to 40 mfp). Results show that of all the glasses under study, the S1 glass sample has the best gamma-ray shielding properties.
The effect of Annona muricata (Graviola) on the prevention of brain damage due to ionizing radiation in rats
(Cell Press, 2024) Elmas, Ozlem; Keskin, Emrah; Sahin, Havva Hande Keser; Guven, Berrak; Almisned, Ghada; Zakaly, Hesham M. H.; Tekin, H. O.
In this study, it was aimed to evaluate the effect of ethanol extract of Annona Muricata (AM) leaves in the prevention of brain damage caused by ionizing radiation (IR). This study was conducted in the Experimental Animal Research Unit of a university with 28 adults female Wistar Albino rats. The experimental groups were as follows: Control group (n = 8), AM group (n = 6), IR group (n = 8), AM + IR group (n = 6). In the IR group, astrocyte hypertrophy, microglial reaction and inflammatory reaction levels were significantly higher than the control and AM groups (P < 0.001). Edema was significantly higher in the IR group compared to the control group (P=0.001). The MDA of the IR group was significantly higher compared to the control group and AM group (P=0.031, P=0.006, respectively). The MDA of the AM + IR group was significantly higher than the AM group (P=0.039). Our findings show that histomorphology and oxidant damage caused by IR can be ameliorated using AM, as demonstrated by the comparison of the controls to AM + IR recipients, which showed similar histomorphology and oxidant damage levels.
Energy deposition responses, transmission factors, and radiation interaction properties of some antibiotics: A critical assessment for substantial molecular alterations as a function of radiation exposure
(Pergamon-Elsevier Science Ltd, 2024) Almansoori, Asma; Almisned, Ghada; Sen Baykal, Duygu; Kilic, Ceyda Sibel; Tekin, H. O.
This study addresses the underexplored area of radiation interaction properties of antibiotics and their implications for stability, efficacy, and structural integrity. Focusing on a range of antibiotics classified by the United Arab Emirates National AMR Surveillance system, the research evaluates key metrics such as attenuation coefficients, effective electron density, exposure buildup factor, and photon transmission factors. Utilizing advanced MCNPX Monte Carlo simulation, we observed varied interaction patterns among different antibiotics, with significant findings on their photon interaction characteristics. The study highlights the potential molecular changes in antibiotics due to radiation exposure, emphasizing the importance of such research in fields from medical radiography to space exploration. Results indicate that radiation exposure can significantly affect antibiotic properties, underscoring the need for careful evaluation of drugs in radiation-rich environments to ensure their effectiveness and safety.
Enhancement of significant colour properties through Ta2O5 incorporation into ZnO-TeO2 binary glasses: An effective method for purposeful utilizations in industry and technology
(Elsevier, 2023) Cokduygulular, Erman; Cetinkaya, Caglar; Kinaci, Baris; Kilic, Gokhan; Tekin, H. O.
The fact that multicomponent glass systems offer tuneable optical properties according to different additive rates increases their potential for use in daily industrial and optoelectronic applications that require high optical and colour performance. Therefore, it is vital to determine the optical and colour performances of glass systems in detail. The purpose of this research is to examine the monotonic effects of Ta2O5 on a set of glass samples and the resulting changes to colour concepts to better understand how to acquire these changes at their optimum level and make the most of the optimization possibilities available with Ta2O5. Accordingly, many optical properties such as Average Visible Transmittance (AVT), colour, Colour Render Index (CRI), Correlated Colour Temperature (CCT) that change with Ta2O5 doping ratio in binary Zinc-Tellurite oxide glasses-based systems are examined and their potential to be used for effective optoelectronic applications are presented. With the addition of Ta2O5 into (25ZnO center dot 75TeO(2))y(Ta2O5)x (x = 0-7 mol% and y = 100-x mol%) glassy system, all optical and colour properties were improved significantly. The Ta2O5 contribution increases the AVT and changes the colour coordinates of the glass system along the Planckian locus curve from the yellow region to the D65 colour coordinates. In addition, a comprehensive analysis of 15 coloured samples is provided, focusing on the cases in which Ta2O5 enhances the CRIext value. An enrichment was observed for TCS07 and TCS14, and a value of 100 was obtained specifically for TCS09 with a 3% Ta2O5 contribution. It can be concluded that the Ta2O5 is a promising multi-functional tool for colour enhancement of ZnO-TeO2 binary glasses making them more suitable for daily applications as well as applications in advanced technological purposes.
Exploring critical behavioral differences in physical, structural, and nuclear radiation attenuation properties of produced High Entropy Alloy (HEA) and Refractory-High Entropy Alloy (RHEA) samples
(Elsevier, 2024) Guler, Seval Hale; Guler, Omer; Kavaz, E.; Almisned, Ghada; Issa, Bashar; Tekin, H. O.
Refractory-High entropy alloys (RHEAs) are known for their exceptional mechanical and radiation-resistant properties, making them promising materials for use in nuclear reactors. Their high entropy composition, which consists of multiple elements in roughly equal proportions, can create a stable microstructure that withstands high levels of radiation damage. The objective of this work is to further our comprehension of the unique behavioral, physical, structural, and nuclear radiation attenuation characteristics shown by High-Entropy Alloys (HEA) and Refractory-High entropy alloy (RHEA) materials. Accordingly, two high entropy alloy (HEA) samples through two different compositions were produced. The first composition under consideration is the typical high-entropy alloy (HEA) defined as MnCrFeNiCoMo0.5. The second composition under consideration is a refractory high entropy alloy (RHEA) characterized by the following elemental composition: TiZrNbHfVTa0.1. SEM and EDX analyses were conducted in terms of determining their physical and structural attributes. Next, a133Ba radioisotope together with a HPGe detector were utilized for gamma-ray transmission experiments. Finally, a241Am/Be source and a gas proportional detector were used for neutron absorption experiments for HEA and RHEA samples. The alloy structures displayed a unique degree of uniformity. Throughout the RHEA phase, the incorporation of refractory elements did not provide any discernible adverse impacts on the physical stability. The counting spectrum provided a clear explanation of the gamma ray absorption features shown by the RHEA (R) sample, highlighting its exceptional absorption properties. Regarding the absorption properties of neutrons, it was observed that RHEA had a comparatively reduced amount of absorption. Therefore, it can be concluded that the basic structure of RHEA grants it superior gamma-ray attenuation qualities compared to HEA. It can be concluded that RHEA demonstrates superior applicability as a material in comparison to HEA, especially in situations involving the use of fuel rods, where maintaining of neutron quantity has paramount importance for achieving optimum neutron activation.
Fabrication and structural, physical, and nuclear radiation shielding properties for Oxide Dispersion-Strengthened (ODS) alloys through Erbium (III) oxide, Samarium (III) oxide, and Praseodymium (III) oxide into 316L matrix
(Elsevier Sci Ltd, 2024) Guler, Seval Hale; Guler, Omer; Kavaz, E.; Almisned, Ghada; Albayrak, M. Gokhan; Issa, Bashar; Tekin, H. O.
We report a comprehensive investigation on customization process of Oxide Dispersion-Strengthened alloys through Sm2O3, Pr2O3, and Er2O3 incorporation into 316L stainless steel matrix in terms of a desired enhancement in structural, physical, and nuclear radiation shielding properties. Oxide powders are incorporated into 316L stainless steel powder all with the same purity of 99.5%. These were Erbium oxide (Er2O3), Praseodymium oxide (Pr2O3), and Samarium oxide (Sm2O3). First, X-Ray diffraction and Scanning Electron Microscope/Energy-dispersive X-ray spectroscopy analyses are conducted in order to investigate their physical and structural properties. Next, two different experimental setups are employed using a133Ba and 241Am/Be sources for the measurements of gamma-ray and neutron transmission properties of Oxide Dispersion -Strengthened alloys. The maximum density increment is achieved through Er2O3 compared to other rein-forced oxides. The detector counting value reached its minimum level when a 5% Er2O3 oxide dispersion was introduced into the 316L SS matrix. Similarly, the most significant degree of photon absorption, the highest values of mass attenuation coefficient, lowest half value layer, and most effective atomic number, were all attained by the same sample. Based on the findings derived from the investigation, it can be concluded that incorporating Er2O3 oxide into 316L steel can be considered as a viable option in terms of enhancing the critical properties of Oxide Dispersion-Strengthened alloys for extreme conditions such as nuclear reactors and other similar fields, where the behavioral attributes of the utilized materials are at utmost importance.
Functional assessment of various rare-earth (RE) ion types: An investigation on gamma-ray attenuation properties of GeO2-B2O3-P2O5-ZnO-Tb2O3-RE magneto-optical glasses
(Elsevier Gmbh, 2023) ALMisned, Ghada; Baykal, Duygu Sen; Ilik, E.; Abuzaid, Mohammed; Kilic, Gokhan; Tekin, H. O.
We report the functional assessment of various rare-earth (RE) ion types on gamma-ray attenu-ation properties of GeO2-B2O3-P2O5-ZnO-Tb2O3-RE (where; RE=0; 1 %Ho, 1 %Pr, 1 %Er, 1 %Nd, 1 %Dy, 1 %Ce) magneto-optical glasses. The elemental fractions and densities of each glass sample were specified separately for the MCNPX Monte Carlo code. In addition to fundamental gamma absorption properties, Transmission Factors throughout a broad radioisotope energy range were measured. According to findings, Holmium (Ho) incorporation into the glass structure resulted in a net increase of 0.3406 g/cm(3), whereas Cerium (Ce) addition resulted in a net in-crease of 0.2047 g/cm(3). The Ho-doped S2 sample was found to have the greatest LAC value, despite the fact that seven glass samples exhibited identical behavior. The Ho-doped S2 sample had the lowest HVL values among the glass groups evaluated in this work, computed in the energy range of 0.015-15 MeV. The lowest EBF and EABF values were reported for Ho reinforced S2 sample with the highes LAC and density values. For all glass samples, a decrease in TF values was observed depending on the increase in thickness. Among the investigated glasses, Ho and Er reinforced samples (i.e., S2 and S4) showed the minimum TF values at used radioisotope energies. It can be concluded that Ho and Er type rare earth elements may provide the most effective gamma ray absorption properties when they are incorporated into the GeO2-B2O3-P2O5-ZnO-Tb2O3 system.
Graphene-bioactive glass composites: Structural, Vickers hardness, and gamma-ray attenuation characteristics
(Frontiers Media Sa, 2023) Deliormanli, Aylin M.; ALMisned, Ghada; Ene, Antoaneta; Tekin, H. O.
Introduction: Graphene-based materials have gained increasing attention for use in radiation attenuation applications. In this study, pristine graphene nanoplatelet-containing (1, 3, 5, and 10 wt%) borate-based bioactive glass composites were prepared. Methods: Structural properties, Vickers microhardness, and gamma-ray radiation shielding properties of the fabricated composites were examined in detail. Results and Discussion: Results revealed that the inclusion of the graphene in the glass matrix led to a decrease in the bulk density of the glass-based composites from 2.41 to 2.31 g/cm(3). Similarly, a decrease in Vickers hardness was obtained as the graphene concentration was increased due to a convoluted effect of the non-uniform distribution of graphene nanoplatelets in the bioactive glass matrix and the higher residual porosity. Vickers hardness of the bare and the 10 wt% graphene-containing bioactive glass discs were measured to be 5.03 +/- 0.28 GPa and 1.87 +/- 0.56 GPa, respectively. On the other hand, the incorporation of graphene starting from 3 wt% decreased the crack propagation after indentation which may be attributed to an increase in fracture toughness. In the study, fundamental gamma ray absorption properties of graphene-containing bioactive glasses were examined in the 0.015-15 MeV incident photon energy range. For this purpose, the Py-MLBUF code was employed to determine gamma ray absorption parameters. Results showed that linear attenuation coefficients of the glass-based composites decreased due to a decrease in the density of the samples. On the other hand, as graphene was incorporated into the bioactive glass structure, exposure buildup factor and energy absorption buildup factor values increased. The growing graphene ratio in the glass structure contributed negatively to the photon's tendency to interact with the material.
Integrated geophysical techniques applied for petroleum basins structural characterization in the central part of the Western Desert, Egypt
(De Gruyter Poland Sp Z O O, 2023) Kamal, Mohamed; Shen, Jinsong; Othman, Adel Ali Ali; Araffa, Sultan Awad Sultan; Tekin, H. O.; Ene, Antoaneta; Abdel-latief, Abdel-Sattar A.
The study area is situated in the central part of the Western Desert of Egypt between latitude 28 degrees 00 ' to 30 degrees 00 ' N and longitude 25 degrees 00 ' to 30 degrees 00 ' E. That region is distinguished by a featureless plain that is divided by depressions in Siwa, Qattara, and Bahariya. The purpose of the current study is to study the predominant struc-tures in the area and how they relate to basin structure. Utilizing aerogravity data (Bouguer gravity, residual gravity, downward continuation, and Euler deconvolution) and aeromagnetic data (reduced to the northern Pole [RTP] anomalies and tilt derivative) is essential to accomplish this purpose. Through both qualitative analyses, these-data were submitted to various processing and interpretation approaches. The subsurface structure configuration trending in E-W, N-S, NW-SE, NE-SW, ENE-WSW, and NNE-SSW directions has been simulated by utilizing aero- gravity and aeromagnetic data. According to these maps, the study area is divided by around 44 faults. The study's findings indicated that the direction of the basement structure was almost NE-SW and N-S. The optimum Euler depth deconvolution at structure index, SI = 0 shows several features in the study area, including Sill, Dyke, Ribbon, and Step structures.
An investigation on gamma-ray and neutron attenuation properties of multi-layered Al/B4C composite
(Elsevier, 2023) Almisned, Ghada; Gunoglu, Kadir; Ozkavak, Hatice Varol; Sen Baykal, Duygu; Tekin, H. O.; Karpuz, Nurdan; Akkurt, Iskender
Nowadays, the concept of multi-layered composite materials is attracting the researchers in terms of enhancing the capabilities of shielding materials as well as extending the scope of utilization towards space sciences and cosmic radiation application. In this study, we report the manufacturing, design, and experimental investigation on newly developed multi-layered Al/B4C shielding composites. Al powder material with a purity of 99% and an average size of 15 & mu;m is used as matrix material. Next, B4C powders with an average size of 9 & mu;m are incor-porated into the matrix as reinforcement material. Accordingly, we manufactured several different multilayer Al-B4C shield samples of 3 cm diameter and 1 cm height through powder metallurgy method. Gamma-ray trans-mission properties are determined using 3 x 3 NaI(Tl) scintillation detector through 60Co and 137Cs point isotropic radioisotopes. Moreover, MCNPX (version 2.7.0) is utilized for deposited energy amount and trans-mission factor calculations for gamma and neutron radiation. Our results showed that geometric configuration plays a crucial role in shielding efficiency of multi-layered materials. Among the manufactured samples, B4C-Al-B4C sample is reported with promising shielding properties against gamma-ray and neutron radiation. A direct relationship between the overall transmission factor values and deposited energy amount (MeV/g) in each sample is also explored for multi-layered composite shields.It was also seen that combination of layers made significantly improvement of radiation shielding properties of materials.
Mechanical, gamma rays and neutron radiation transmission properties for some ZnO-TeO2-P2O5-ZnX glasses
(Elsevier Sci Ltd, 2023) Kilic, G.; Ilik, E.; Kavaz, E.; Almisned, Ghada; Sen Baykal, Duygu; Tekin, H. O.
Oxyhalide glasses are utilized in the process of immobilizing nuclear waste and function as scintillating agents for the purpose of radiation detection. The objective of this study is to examine the enhanced mechanical and radiation attenuation characteristics of newly developed oxyhalide glasses by incorporating zinc-iodide. This study investigates the synthesis process, mechanical properties, and experimental gamma-neutron radiation transmission properties. A halogen-free base glass, consisting of an oxide mixture of P2O5, TeO2, and ZnO, was synthesized. Following that, the initial glass composition was further strengthened by the addition of zinc bromide (ZnBr2), zinc chloride (ZnCl2), zinc fluoride (ZnF2), and zinc iodide (ZnI2) in a successive manner. The experimental configuration entailed positioning circular glass samples between a 133Ba radioisotope and a Canberra High Purity Germanium (HPGe) detector. The determination of attenuation coefficients is achieved through the measurement of individual attenuation properties. Afterwards, theoretical approaches are utilized to determine the mechanical characteristics of halogenated glasses, including Young's modulus (Y), Bulk modulus (K), Shear modulus (G), Longitudinal modulus (L), and Poisson's modulus (v). The results of the study suggest that the implementation of the halogenation process on the P2O5-TeO2-ZnO base composition led to a significant enhancement in the examined properties. The incorporation of zinc-iodide in the halogenation process resulted in a significant improvement in the gamma absorption properties. The utilization of zinc in the halogenation process demonstrates multifunctional capabilities, which involve the potential to enhance various glass properties, including durability and gamma-ray absorption properties. It can be concluded that zinc-iodide demonstrates enhanced halogenation capabilities in comparison to zinc bromide, zinc chloride, and zinc fluoride.
Neutron transmission analysis in borated polyethylene, boron carbide, and polyethylene: Insights from MCNP6 simulations
(Pergamon-Elsevier Science Ltd, 2024) Almisned, Ghada; Susoy, G.; Tekin, H. O.
This study delves into the neutron transmission properties of three pivotal materials: borated polyethylene, boron carbide (B4C), and polyethylene, employing the advanced MCNP6 (version 6.2) Monte Carlo code. The primary objective was to discern the impact of boron content and material density on neutron transmission efficacy. Results highlighted the formidable neutron shielding prowess of B4C, which exhibited the lowest neutron transmission factor among the studied materials. Borated polyethylene samples revealed an inverse correlation between boron concentration and neutron transmission, emphasizing boron's paramountcy in neutron attenuation. In contrast, polyethylene showcased notable neutron moderating capabilities, necessitating synergistic integration with materials possessing higher neutron absorption cross-sections for superior neutron shielding. Material density and the presence of other elemental constituents further influenced neutron transmission. The research provides a comprehensive understanding of neutron-material interactions, setting the groundwork for enhanced safety measures in nuclear applications.
Oxides dispersion-strengthened (ODS) FeCoNiCuZn high entropy alloys through different rare earth elements: Synthesis, structural, physical, and experimental radiation transmission properties
(Elsevier Sci Ltd, 2023) Guler, Omer; Kavaz, E.; Guler, Seval Hale; Almisned, Ghada; Ozkul, Iskender; Basgoz, Oykum; Tekin, H. O.
The oxide dispersoids within ODS alloys can act as sinks for radiation-induced defects, such as vacancies and dislocation loops, effectively reducing their mobility and preventing their accumulation. This property is crucial for HEAs employed in radiation-intensive environments, such as nuclear reactors. The objective of this research is to examine the impact of rare earth elements (REE) such as Y2O3, Er2O3, Pr2O3, and Sm2O3, on Oxides Dispersion-Strengthened (ODS) FeCoNiCuZn High Entropy Alloys (HEAs). The mechanical alloying technique is employed to produce a high entropy alloy consisting of Fe, Co, Ni, Cu, and Zn in their raw form. Subsequently, the raw alloy powder is enriched with separate amounts of Y2O3, Er2O3, Pr2O3, and Sm2O3. The microstructural analysis of the samples obtained from the mechanical alloying process was performed utilizing the X-ray diffraction (XRD) technique. In addition, scanning electron microscopy (SEM) was employed to analyze the ODSHEA samples encoded S1, S2, S3, S4, and S5. To investigate the transmission properties of gamma-ray and neutron radiation, experimental studies are carried out using two types of detectors: Ultra High Purity Germanium (HPGe) detector and Canberra NP-100B BF3 gas proportional detector, respectively. The X-ray diffraction (XRD) spectra of samples did not display any observable peaks that could be attributed to the presence of dispersed rare earth element (REE) oxides. The uniform distribution of the metallic constituents that make up the High Entropy Alloy (HEA) is observed in the samples. Additionally, it can be observed that the implementation of the ODS-HEA technique, incorporating a 3% (wt.) Er2O3 additive, results in the most advantageous results with respect to the characteristics of gamma ray absorption. The S3 sample demonstrated the greatest degree of neutron absorption, as demonstrated by a recorded value of 0.857 mu Sv/h, where the S1 sample demonstrated the minimum level of absorption, as evidenced by a recorded value of 0.452 mu Sv/h. Based on the observed effects on neutron and gamma-ray attenuation behaviors in ODS-HEAs, it can be concluded that Er2O3 exhibits characteristics of a monotonic oxide. This feature is particularly advantageous for applications that necessitate a dual enhancement in these behaviors. It can also be concluded that the S1 sample may be deemed appropriate for situations where the utmost consistency of chain reactions in nuclear reactor fuel rods is desired, due to its possession of the lowest neutron absorption properties.
The role of ZrO2 as glass-network former on radiation transmission properties of aluminoborosilicate (ABS) glasses: A glass type for nuclear waste immobilization
(Elsevier Sci Ltd, 2023) Almisned, Ghada; Sen Baykal, Duygu; Ilik, E.; Kilic, G.; Tekin, H. O.
We report the gamma-ray shielding properties, transmission factors and, effective removal cross section values of several aluminoborosilicate glasses that have been synthesized through various glass-forming materials such as Al2O3, B2O3, SiO2, and ZrO2. The study utilized the elemental compositions and densities of eight different glass samples as input variables in theoretical calculations and Monte Carlo simulations. According to the results obtained, it was seen that the network-forming type used in aluminoborosilicate glasses had a direct effect on the radiation absorption properties of the glasses. The utilization of ZrO2 and Cs2O at the highest concentration as the network former and glass network modifier in the NCBZ-6 sample yielded the most advantageous results in relation to its gamma-ray absorption capabilities. The benefit is intrinsically related to the heightened density of glass and the incorporation of compounds with increased atomic numbers, both of which are fundamental characteristics desired in materials designed for the purpose of gamma-ray absorption. However, the enhanced capability of ZrO2 to absorb gamma-rays excludes the absorption of high-energy neutrons. The absence of boron trioxide (B2O3) in the NCBZ-6 sample can be ascribed to its restricted availability against fast neutrons. The continued existence of ZrO2 as a network forming in the investigated ABS glasses is likely to result in improved material homogeneity and progressive enhancement of gamma-ray absorption characteristics. It can be concluded that the incorporation of ZrO2 as a network-former component may be an appropriate strategy to enhance the gamma-ray shielding capabilities of aluminoborosilicate glasses.
Sodium metaphosphate-tungsten trioxide glasses: a characterization study on gamma-ray shielding properties and transmission factors (TFs)
(Springer, 2023) Almisned, Ghada; Rammah, Y. S.; Zakaly, Hesham M. H.; Baykal, Duygu Sen; Issa, Shams A. M.; Ene, Antoaneta; Tekin, H. O.
In the present study, gamma-ray attenuation properties as well as transmission factor values of high-density sodium metaphosphate-tungsten trioxide glasses with chemical composition of (40-x)NaPO3-xWO3-60Sb2O3: (x = 0 (S1), 5 (S2), 10 (S3), 15 (S4), 20 (S5), 30 (S6), and 40 (S7) mol%) have been investigated. MCNPX general purpose Monte Carlo code and Phy-X/PSD program were utilized for the calculation of transmission factor values and fundamental gamma-ray shielding parameters. Our findings suggest that the S7 sample (with the highest WO3 content mole%) has possessed the maximum mass attenuation coefficients (mu m) at all gamma-ray energies investigated. In terms of half value layer (HVL) and mean free path (MFP), the coded glass sample S7 has achieved the minimum values. The effective atomic number (Zeff) and equivalent atomic number (Zeq) of the investigated glasses have the same trend of mass attenuation coefficient. The raising of WO3 content in mole% in glasses leads to reducing both exposure and absorption buildup factor values for all mean free path values. The minimum transmission factor (maximum attenuation) quantities were verified at a thickness of 3 cm for all investigated glasses. It can be concluded that the S7 sample exhibits superior radiation shielding characteristics.
Synthesis, optical, structural, physical, and experimental gamma-ray transmission properties of high-density lead-boro-tellurite glasses: A multi-phases investigation towards providing a behavioral symmetry through Lead(II) oxide
(Elsevier Sci Ltd, 2023) Kurtulus, Recep; Kavas, Taner; Kavaz, Esra; ALMisned, Ghada; Tekin, H. O.
We report the synthesis and multiple material properties of newly designed high-density lead-boro-tellurite glass system. The glass formulation as zPbO + [(100-z)(0.2B2O3 + 0.8TeO2)], where z: 10, 15, 20, and 25 mol%, were synthesized using a traditional melting technique around 625 to 725 degrees C. After successfully preparing the glass samples coded BT20-Pb10, BT20-Pb15, BT20-Pb20, and BT20-Pb25, some physical, structural, and optical an-alyses were included to serve up a broad understanding. BT20-Pb10, had a density of 5.4125 g/cm3, whilst BT20-Pb25 possessed a density of 6.0756 g/cm3. According to the XRD method, all samples except for BT20-Pb25 had an amorphous structure without any sharp peaks. Furthermore, the transmission percentage was in a decreasing trend parallel to the increasing PbO concentration. This phenomenon also influenced on energy bandgap values to reduce from 2.70 to 2.45 eV for BT20-Pb10 to BT20-Pb25 samples, respectively. In addition to the material characterizations, we studied experimental and theoretical radiation shielding properties. Using experimental methods, the photon absorption properties of the manufactured glasses were studied, and we found out that the BT20-Pb25 sample exhibited the highest MAC values among the compared glasses. Based on MAC findings, other essential parameters, such as HVL and Zeff, were found to be in enhancing way as PbO increased in the glass network. In the context of benchmarking of findings with theoretical and experimental results, it was clearly demonstrated that precise harmony reigns when all eight energy values are taken into account. To sum up, BT20-Pb25 may be regarded as a potential shielding glass for various applications in radiation fields owing to its significant material properties and shielding performance against energetic photons.
Synthesis, structural, optical and experimental gamma-ray shielding properties of molybdenum-trioxide reinforced CRT glasses
(Springer, 2024) Kurtulus, R.; Kavaz, E.; Kavas, T.; Almisned, Ghada; Perisanoglu, U.; Tekin, H. O.
While sustainable material systems have become paramount, recycling unused waste cathode ray tubes (CRTs) glass can possess great potential for radiation protection applications. With this motivation, the present study addressed the utilization of waste CRTs in combination with MoO3 towards a glass composition of xMoO(3)-(100-x)CRTs where x typifies 0, 1, 3, and 5 wt%. The glass samples coded Mo0 to Mo5 were synthesized using a traditional melting technique. After successfully preparing the glass series, some sets of characterization analyses were performed to understand physical, structural, optical, and radiation shielding properties. According to the findings, density increased from 2.92 to 2.96 g/cm(3) as MoO3 was introduced into the glass network. Yet more, all glass samples exhibited an amorphous structure irrespective of varying MoO3 doping rates. On the other hand, FTIR measurements paved the way for highlighting possible vibrational modes, such as Si-O-Si and Si-O, in the structure. According to the optical properties via UV-Vis, the direct E-g values equaled 1.75, 1.69, 1.65, and 1.61 eV for Mo0 to Mo5, respectively, whereas R values ranged from 2.8534 to 2.9281. For investigating mass attenuation coefficients (MAC), the transmission measurements were performed for 30.9-383 keV photon energy ranges using radioactive source of 133-Ba and Ultra-Ge detector. The correctness of the experimental MAC values were checked with EpiXS program and MCNP codes. It is determined that the highest MAC values changing from 0.5951 cm(2)/g to 0.1022 cm(2)/g belong to Mo5 glass for 30.9-383 keV. It is also revealed that with the increasing MoO3 addition, EABF, EBF, HVL and MFP values of the Mo0-Mo5 glasses dropped and MAC, Z(eff) and N-el values enhanced. As a result, MoO3 substitution has improved the material characteristics of CRTs glasses.

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