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    A benchmarking analysis on different rubber materials: towards customisation of lightweight and effective radiation protection solutions for aerospace and electronic applications
    (Springer, 2024) Alkarrani, Hessa; ALMisned, Ghada; Tekin, Hüseyin Ozan
    This study examines the efficacy of rubber, a non-toxic hydrocarbon polymer, as a shielding material against gamma rays and neutrons. We analyse four types of rubbers: Neoprene, Butyl, Natural, and Silicone, using computational methods and Monte Carlo simulations via MCNP (version 6.3) to evaluate their gamma ray and neutron shielding parameters. Notably, Neoprene, enhanced with chlorine, shows superior gamma ray attenuation capabilities with a mass attenuation coefficient (MAC) of 760.446 cm2/g at 0.015 MeV, indicating its potential as an effective material for gamma ray shielding applications. Conversely, Butyl rubber, with its high hydrogen content, exhibits exceptional neutron attenuation properties, with the highest Sigma R value of 11.861 1/cm, making it a preferred choice for neutron shielding. This investigation underscores the versatility and environmental benefits of rubber materials in radiation protection, highlighting their potential as lightweight, customisable and sustainable alternatives to conventional shielding substances like lead. Our findings reveal prominent advantages of Neoprene for gamma ray shielding and Butyl rubber for neutron protection, contributing to the development of safer, more effective radiation protection solutions.
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    A comparative investigation on mechanical, gamma-ray and neutron shielding properties of some iron and boron containing concretes samples for nuclear safety applications
    (Elsevier Ltd, 2024) ALMisned, Ghada; Susoy, Gülfem; Sen Baykal, Duygu; Tekin, Hüseyin Ozan
    This study explores the gamma-ray and neutron shielding properties of fourteen different concrete samples, each tailored with varying percentages of Boron Carbide, Iron, and Iron Boride. Using the MCNP 6.3 Monte Carlo code, we calculated transmission factors for photon energies of 0.662 MeV, 1.1732 MeV, and 1.3325 MeV, and analyzed the impact of concrete thickness on shielding efficacy. Additionally, the Phy-X/PSD software was used to compute critical parameters such as linear and mass attenuation coefficients, half-value layer, tenth-value layer, mean free path, and fast neutron removal cross-section to gain a comprehensive understanding of each material's shielding capabilities. Our findings indicate that adding iron to the concrete matrix significantly enhances its attenuation properties, with the 20%Fe+80%Concrete sample outperforming all others. This composition demonstrated the lowest transmission factors across all tested energies and thicknesses, indicating superior photon attenuation. Moreover, the 20%Fe+80% Concrete exhibited the highest fast neutron removal cross-section, making it highly effective for environments requiring neutron shielding. In addition to the shielding properties, we analyzed the Elastic (Young's) Modulus of the concrete samples to understand their mechanical properties. Standard Concrete had an Elastic Modulus of 261.24 GPa, while the introduction of boron carbide significantly enhanced the Elastic Modulus, with pure boron carbide concrete exhibiting a value of 518.88 GPa. Concrete samples with varying percentages of boron carbide (5%, 10%, 15%, and 20%) showed a progressive increase in Elastic Modulus, indicating that higher proportions of boron carbide consistently enhance the material's stiffness. Conversely, concrete samples with iron boride and iron showed slight reductions in Elastic Modulus. It can be concluded that the boron carbide enhances stiffness, iron and iron boride provide a balance between stiffness and other properties. In conclusion, the 20%Fe+80%Concrete is a standout material that could greatly improve radiation shielding, offering major benefits. © 2024 Elsevier Ltd
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    A critical assessment of the mechanical strength and radiation shielding efficiency of advanced Concrete composites and Vanadium Oxide-Glass container for enhanced nuclear waste management
    (Elsevier B.V., 2024) Tekin, Hüseyin Ozan; ALMisned, Ghada; Kılıç, Gökhan; İlik, Erkan; Susoy, Gülfem; Elshami, Wiam E.; Issa, Bashar
    The nuclear industry produces large quantities of low, intermediate, and high levels of radioactive waste, all of which require safe management during both transport and storage. This study evaluates the radiation shielding effectiveness and mechanical properties of four distinct container materials: Pb Composite Glass, 0.5 Cement-0.5 Bitumen, Concrete (Steel-Magnetite), and C9 (BCBV0.5) Vanadium Oxide-Glass. Using Monte Carlo simulations and theoretical methods, we determined the Transmission Factors (TF) and Half-Value Layers (HVL) for each material. The TF indicates the effectiveness of a material in attenuating radiation, calculated by the ratio of gamma rays exiting the material to those entering it. Lower TF values signify better radiation shielding. The HVL is the thickness of material required to reduce the intensity of gamma rays by half, with lower HVL values indicating more effective shielding. Concrete (Steel-Magnetite) demonstrated superior performance with the lowest TF values (e.g., 1.0 × 10-1 at 0.662 MeV and 1 cm thickness) and HVL values (e.g., 2.5 cm at 1.3325 MeV), alongside a high elastic modulus of 163.15 GPa, indicating its robustness for high-energy gamma-ray applications. Pb Composite Glass also showed strong performance with a TF of 9.5 × 10-2 at 0.662 MeV and 1 cm thickness, an HVL of 2.0 cm at 0.662 MeV, and an elastic modulus of 41.54 GPa. The C9 (BCBV0.5) Vanadium Oxide-Glass, with an elastic modulus of 73.79 GPa, outperformed the 0.5 Cement-0.5 Bitumen mixture in both TF (e.g., 1.15 × 10-1 at 0.662 MeV and 1 cm thickness) and HVL (e.g., 4.2 cm at 1.1732 MeV) measurements, highlighting its potential as a more effective alternative. It can be concluded that C9 (BCBV0.5) Vanadium Oxide-Glass presents promising properties for future advancements in radiation protection, warranting further research and optimization. © 2024 The Author(s)
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    A critical evaluation on nuclear safety properties of novel cadmium oxide-rich glass containers for transportation and waste management: Benchmarking with a reinforced concrete container
    (Frontiers Media SA, 2022) ALMisned, Ghada; Baykal, Duygu Şen; Kılıç, Gökhan; İlik, Erkan; Zakaly, Hesham M.H.; Ene, Antoaneta; Tekin, Hüseyin Ozan
    We examine the nuclear safety properties of a newly designed cadmium oxide-rich glass container for nuclear material to a bitumen-reinforced concrete container. Individual transmission factors, detector modelling, and energy deposition (MeV/g) in the air are calculated using MCNPX (version 2.7.0) general purpose Monte Carlo code. Two container configurations are designed with the material properties of cadmium dioxide-rich glass and Concrete + Bitument in consideration. First, individual transmission factors for 60Co and 137Cs radioisotopes are calculated. To evaluate potential environmental consequences, energy deposition amounts in the air for 60Co and 137Cs are also determined. The minimum gamma-ray transmission rates for two container types are reported for a cadmium dioxide-rich glass container. In addition, the quantity of energy deposition is varied depending on the container type, with a lower value for cadmium dioxide-rich glass container. The 40% cadmium dioxide-doped glass container provides more effective safety than the Cement + Bitumen container, according to the overall findings. In conclusion, the utilization of cadmium dioxide-doped glass material along with its high transparency and advanced material properties may be a significant and effective option in areas where concrete is required to assure the safety of nuclear materials. Copyright © 2022 ALMisned, Baykal, Kilic, Ilik, Zakaly, Ene and Tekin.
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    A first-time fusion of TiNbWMoZrOx high entropy oxide (HEO) with zinc-tellurite glass: Toward superior physical properties
    (Elsevier B.V., 2024) Kılıç, Gökhan; Güler, Ömer; Kavaz, Esra; İlik, Erkan; Güler, Seval Hale; ALMisned, Ghada; Tekin, Hüseyin Ozan
    While numerous oxide additives have traditionally been employed to enhance the radiation shielding capabilities of glasses, the unique attributes of high-entropy oxides (HEOs), a group of materials acclaimed in contemporary material science for their distinctive properties have remained unexamined in this specific area. This novel study explores the enhancement of radiation shielding properties in zinc-tellurite glasses through the integration of TiNbWMoZrOx High Entropy Oxides (HEO). Utilizing advanced synthesis techniques, including mechanical alloying and oxidation, the research successfully incorporates HEOs into glass matrices, aiming to improve gamma-ray and neutron attenuation. Characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) confirms the uniform distribution and structural integrity of the HEOs within the glasses. The synthesis of glass samples with a base structure suitable for the molar composition of 25ZnO.75TeO2 (mol%) and glass samples doped with TiNbWMoZrOx (HEO) was carried out using the traditional high-temperature melting and annealing method. The outcomes demonstrate a concentration-dependent increase in shielding efficacy, particularly highlighting the superior performance of glasses doped with 4 mol% of TiNbWMoZrOx (HEC2–4), which exhibit significantly enhanced mass attenuation coefficients, lower half-value layers, and higher effective atomic numbers. This indicates the effective role of HEOs in boosting radiation protection capabilities. Comparative analysis with traditional shielding materials showcases the HEC2–4 glasses' competitive advantage, underlining their potential as a versatile shielding solution. It can be concluded that incorporating TiNbWMoZrOx high entropy oxides into zinc-tellurite glasses significantly augments their radiation shielding properties, offering a novel approach for enhancing protection against gamma-ray and neutron in various applications. © 2024 Elsevier B.V.
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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.
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    Comparative analysis on application conditions of indium (III) oxide-reinforced glasses in nuclear waste management and source transportation: A Monte Carlo simulation study
    (Cell Press, 2023) ALMisned, Ghada; Baykal, Duygu Sen; Kilic, G.; Ilik, E.; Rabaa, Elaf; Susoy, G.; Zakaly, Hesham M. H.
    This study's primary objective is to provide the preliminary findings of novel research on the design of Indium (III) oxide-reinforced glass container that were thoroughly developed for the purpose of a nuclear material container for transportation and waste management applications. The shielding characteristics of an Indium (III) oxide-reinforced glass container with a certain elemental composition against the 60Co radioisotope was thoroughly evaluated. The energy deposition in the air surrounding the designed portable glass containers is measured using MCNPX general-purpose Monte Carlo code. Simulation studies were carried out using LenovoP620 workstation and the number of tracks was defined as 108 in each simulation phase. According to results, the indium oxide-doped C6 (TZI8) container exhibits superior protective properties compared to other conventional container materials such as 0.5Bitumen-0.5 Cement, Pb Glass composite, Steel-Magnetite concrete. In addition to its superiority in terms of nuclear safety, it is proposed that the source's simultaneous observation and monitoring, as well as the C6 (TZI8) glass structure's transparency, be underlined as significant advantages. High-density glasses, which may replace undesirable materials such as concrete and lead, provide several advantages in terms of production ease, non-toxic properties, and resource monitoring. In conclusion, the use of Indium (III) oxide-reinforced glass with its high transparency and
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    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.
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    Enhanced radiation shielding via incorporating europium oxide in 316L stainless steel: Synthesis, physical, microstructural, shielding, and mechanical properties
    (Elsevier Editora Ltda, 2025) Tekin, Hüseyin Ozan; Yayla, Nihal; Albayrak, M.Gökhan; Güler, Ömer; Baykal, Duygu Şen; Alkarrani, Hessa; ALMisned, Ghada
    316L stainless steel is widely utilized in various industries due to its excellent corrosion resistance, mechanical strength, and biocompatibility, making it a preferred material for applications in nuclear filed. However, enhancing its radiation shielding and mechanical properties through reinforcement strategies, such as the addition of high-Z materials like Europium(III) oxide, is crucial for extending its functionality in high-radiation environments, where improved performance is essential for safety and durability. In this study, 316L stainless steel composites reinforced with varying amounts of Eu2O3 (1%, 5%, 10%, and 20%) were synthesized and investigated for their structural, mechanical, and radiation shielding properties. X-ray diffraction (XRD) analysis revealed that the face-centered cubic (FCC) structure of the steel matrix was preserved up to 5% Eu2O3 reinforcement, while higher concentrations led to phase formation and crystallographic changes. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis showed uniform element distribution at low reinforcement levels, with particle clustering at 20% Eu2O3. Transmission factors (TFs) were evaluated using PHITS simulations for photon energies of 0.662 MeV, 1.1732 MeV, and 1.3325 MeV. The 20% Eu2O3 composite exhibited the lowest TF and highest attenuation properties, confirmed by mass and linear attenuation coefficients. Elastic modulus values decreased from 224.46 GPa in pure 316L to 189.26 GPa with 20% Eu2O3 reinforcement, reflecting the inverse relationship between mechanical stiffness and radiation shielding performance. Benchmarking against other shielding materials demonstrated superior performance of the Eu2O3-reinforced steel in gamma-ray attenuation. The 20% Eu2O3 composite shows strong potential for applications in nuclear radiation shielding where attenuation efficiency is prioritized over mechanical properties. © 2024 The Authors
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    Exploring the gamma-ray shielding performance of boron-rich high entropy alloys
    (Elsevier Ltd., 2025) Alan, Hatice Yılmaz; Güler, Ömer; Yılmaz, Ayberk; Susam, Lidya Amon; Kavaz, Esra; Kılıç, Gökhan; İlik, Erkan; Oktik, Şener; Akkuş, Baki; ALMisned, Ghada; Tekin, Hüseyin Ozan
    High entropy alloys (HEAs) are innovative materials combining multiple principal elements, known for their exceptional properties and wide-ranging applications. This study assesses the gamma-ray shielding capacity of twelve boron-based HEAs through advanced computational methods. Key parameters in terms of understanding the material's ability to reduce radiation intensity, specifically half-value layer (HVL) and tenth-value layer (TVL); its capacity to absorb or scatter photons, including mass attenuation coefficient (MAC) and linear attenuation coefficient (LAC); and other related factors such as equivalent atomic number (Zeq), effective atomic number (Zeff), effective electron density (Neff), mean free path (MFP), and fast neutron removal cross-section (FNRCS) were calculated for photon energies between 0.015 and 15 MeV using the computational method Phy-X/PSD (Photon Shielding and Dosimetry). Additionally, the interaction of alpha particles and protons with these alloys was assessed by calculating energy deposition KERMA (Kinetic Energy Released per Unit Mass) and mass stopping power (MSP) using PAGEX (interaction of protons, alpha, gamma rays, electrons, and X-rays with matter) software, while SRIM (Stopping and Range of Ions in Matter) was employed to estimate particle penetration depths. Electron interactions were evaluated using ESTAR (Stopping Power and Range Tables for Electrons) for stopping power and penetration depth. Among the alloys, Sample 10, S10, (Zr10.8%-Hf21.3%-Nb11.0%-Ta21.6%-W22.0%-B13.1%) exhibited efficient shielding properties due to its high density and interaction characteristics. It can be concluded that boron-based HEAs with optimized compositions and high densities demonstrate significant potential for advanced radiation protection applications. © 2025 Elsevier Ltd
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    Exploring the Radioprotective Indium (III) Oxide Screens for Mammography Scans Using a Three-Layer Heterogeneous Breast Phantom and MCNPX: A Comparative Study Using Clinical Findings
    (Mdpi, 2023) ALMisned, Ghada; Elshami, Wiam; Kilic, Gokhan; Ilik, Erkan; Rabaa, Elaf; Zakaly, Hesham M. H.; Ene, Antoaneta
    Background: During mammography, a lead-acrylic protective screen is recommended to reduce radiation exposure to the unexposed breast. Objectives: This research study aimed to construct an Indium-(III)-oxide-rich tellurite-glass screen (TZI8) and compare its performance to that of lead acrylic. Materials and Methods: A three-layer heterogeneous-breast phantom was developed, using the MCNPX (version 2.7.0) Monte Carlo code. An MCNPX-simulation geometry was designed and implemented, using the lead-acrylic and TZI8 shielding screens between the right and left breast. Next, the reliability of the phantom and the variations in absorption between the lead-acrylic and TZI8 glass were investigated. Results: The findings show that the TZI8-protective-glass screen offers significantly greater radioprotection than the lead-acrylic material. The quantity of total dose absorbed in the unexposed breast was much lower for TZI8 than for lead-based acrylic. The TZI8-glass screen gives about 60% more radioprotection than the lead-acrylic screen. Conclusion: Considering the toxic lead in the structure that may be hazardous to the human tissues, the TZI8-glass screen may be used in mammography examination to provide greater radioprotection than the lead-acrylic screen, in order to greatly reduce the dose to the unexposed breast.
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    First-ever fusion of high entropy alloy (HEA) with glass: Enhancing of critical properties of zinc-tellurite glass through TiZrNbHfTaOx incorporation
    (Elsevier Ltd, 2024) Güler, Ömer; Kılıç, Gökhan; Kavaz, E; İlik, Erkan; Güler, Seval Hale; ALMisned, Ghada; Tekin, Hüseyin Ozan
    Many oxide additives have historically been used to enhance the radiation shielding properties of glasses, yet the potential of high-entropy oxides (HEOs), which have gained popularity in material science for their unique properties, has not been explored in this context. This study is the first to investigate the radiation shielding capabilities of Zinc-Tellurite glass infused with High Entropy Oxide (HEO), specifically utilizing the novel attributes of a synthesized TiZrNbHfTa. In this study, the nuclear shielding properties of newly fabricated Zinc-Tellurite glasses doped with TiZrNbHfTaOx with a composition (25ZnO·75TeO2)100-x. (TiZrNbHfTaOx)x (x = 0, 1, 2, 3, 4 mol%) were studied. Through the synthesis of a TiZrNbHfTa HEA and its integration into glass structure, we have developed a series of novel materials with enhanced protective properties against both gamma-ray and neutron radiation. Experimental results demonstrate that the HEO-infused glass, particularly the HEC1-4 composition, significantly surpasses traditional shielding materials in neutron attenuation, evidenced by its superior effective neutron removal cross-section. Additionally, the HEC1-4 glass demonstrates improved gamma-ray shielding capabilities, with increased mass attenuation coefficients and decreased half-value layers, indicating a higher capacity for photon interaction and absorption. It can be concluded that the incorporation of High Entropy Alloys into glass matrices not only opens a new frontier in radiation shielding materials but also provides a versatile and effective solution with considerable potential for enhancing safety measures in radiation-prone environments. © 2024 Elsevier Ltd and Techna Group S.r.l.
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    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.
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    Gadolinium-tungsten-boron trioxide glasses: A multi-phase research on cross-sections, attenuation coefficients, build-up factors and individual transmission factors using MCNPX
    (Elsevier, 2022) ALMisned, Ghada; Sen Baykal, Duygu; Ali, Fatema T.; Bilal, Ghaida; Kılıç, Gökhan; Tekin, Hüseyin Ozan
    The oxide of the rare earth element gadolinium has the chemical formula Gd2O3. Also known as gadolinium sesquioxide, gadolinium trioxide, and Gadolinia, gadolinium oxide. In this study, various types of fundamental cross-sections, attenuation coefficients, build-up factors and individual transmission factors of high density gadolinium-tungsten-boron trioxide glasses with a chemical composition of (70-x)WO3-xGd2O3 –30B2O3 (where x: 17.5, 20.0, 22.5, 25.0 and 27.5 mol%) are determined using advanced Monte Carlo methods. In addition, gamma transmission factors (TFs) for a range of medical and industrial radioisotopes were calculated using MCNPX (version 2.7.0) Monte Carlo code. The investigated glasses were classified Gd17.5, Gd20.0, Gd22.5, Gd25.0, and Gd27.5 in accordance with xGd2O3. Our findings suggest that the Gd27.5 sample (with highest of Gd2O3 content mol. %) has possessed the maximum linear (µ) and mass (µ/?) attenuation coefficients at all gamma-ray energies investigated. The coded glass sample Gd27.5 is achieved the maximum effective atomic number (Zeff) and effective electron density (Neff) owing its superior attenuation properties. In terms of build-up factors, increasing the concentration of xGd2O3 in glasses is decreased the EBF and EABF values for all mean free path values (0.5–40 mfp). At a thickness of 3 cm, the lowest transmission factor (i.e., highest attenuation) was verified for all Gd17.5-Gd27.5 glasses investigated. Consequently, the Gd27.5 sample exhibits superior radiation shielding properties for a large range of photon energy and various medical and industrial radioisotope energies. © 2022 Elsevier GmbH
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    Gallium (III) oxide reinforced novel heavy metal oxide (HMO) glasses: A focusing study on synthesis, optical and gamma-ray shielding properties
    (Elsevier, 2022) Kassab, L.R.P.; Issa, Shams A.M.; Mattos, G.R.; ALMisned, Ghada; Bordon, C.D.S.; Tekin, Hüseyin Ozan
    In this study, three heavy metal oxide glasses (A:46.0PbO-42.0Bi2O3-12.0Ga2O3, B:45.94PbO-42.66Bi2O3-10.0Ga2O3-1.4BaO, C:72.8PbO-17.0GeO2-10.2Ga2O3) were synthesized to determine their optical and gamma-ray shielding properties in terms of assessing their potential applications in medical and industrial radiation facilities. Glasses were synthesized using melt quenching method. The optical band gap energy is calculated by the absorption spectrum measured at room temperature. We found a large band at 500 nm that refers to Bi+ions and appears to samples A and B that contain Bi2O3 in their compositions. Optical band gap energies were reported as 2.014 ev, 2.055 eV and 2.430 eV for A, B and C samples, respectively. Next, fundamental gamma-ray parameters were also determined using MCNPX general Monte Carlo code and Phy-X/PSD in 0.15–15 MeV photon energy. Our findings clearly showed that the B sample, which includes the highest concentration of Bi2O3, has a considerable advantage in terms of gamma-ray attenuation. Moreover, the results also showed that sample B has significantly higher attenuation properties than shielding concretes and several glass shields. It can be concluded that Bi2O3 is a useful component for heavy metal oxide glasses in terms of improving gamma-ray shielding capabilities for radiation shielding applications. © 2022 Elsevier Ltd and Techna Group S.r.l.
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    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.
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    Heavy metal oxide (HMO) glasses as an effective member of glass shield family: A comprehensive characterization on gamma ray shielding properties of various structures
    (Elsevier Editora Ltda, 2022) Tekin, Hüseyin Ozan; Susoy, Gülfem; Issa, Shams A.M.; Ene, Antoaneta; ALMisned, Ghada; Rammah, Y.S.; Ali Fatema, T.; Algethami, Merfat; Zakaly, Hesham M.H.
    Using advanced Monte Carlo simulation techniques and theoretical methodologies, a thorough investigation on the gamma-ray shielding properties of several heavy metal oxide glasses were performed. The general-purpose Monte Carlo code MCNPX (version 2.7.0) was used to simulate gamma-ray transmission to determine fundamental attenuation coefficients. The acquired findings were compared to Phy-X/PSD to confirm that the outputs were consistent. Additionally, other gamma-ray shielding parameters were computed and studied throughout a broad photon energy range of 0.015 MeV–15 MeV. From A to F glass samples, a sharp density increase from 5.99 g/cm3 to 8.9 g/cm3 was found. As a result, the F sample was found to have the highest linear attenuation coefficients. Our results indicate that increasing the amount of Bi reinforcement improved the material's overall gamma-ray attenuation properties. The F sample with the highest Bi reinforcement in its glass structure was subsequently shown to have superior gamma-ray shielding characteristics. Finally, we compared the F sample's half-value layer values to those of other commercial glass shields, various concretes, and other glass shields investigated in the literature. As a consequence of the benchmarking procedure, it has been determined that the F sample has better shielding capabilities than other shielding materials. It can be concluded that heavy metal oxide glasses offer apparent benefits in terms of more efficiently attenuating incoming gamma-rays. Additionally, it can be concluded that applying high Bi to heavy metal oxide glasses is a beneficial strategy for improving the gamma-ray attenuation capabilities of heavy metal oxide glasses. © 2022 The Author(s)
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    High-Density Lead Germanate Glasses with Enhanced Gamma and Neutron Shielding Performance: Impact of PbO Concentration on Attenuation Properties
    (Prof.Dr. İskender AKKURT, 2025) Alkarrani, Hessa; Şen Baykal, Duygu; ALMisned, Ghada; Tekin, Hüseyin Ozan
    Lead germanate glasses, improved with lead oxide (PbO), have emerged as effective materials for radiation shielding due to their increased density and structural robustness. The goal of this study is to find out how well lead germanate glasses with PbO concentrations between 20 and 55 mol% can block gamma rays and neutrons. The Phy-X/PSD software was used to obtain important numbers like the mass attenuation coefficient (MAC), the linear attenuation coefficient (LAC), the half-value layer (HVL), the mean free path (MFP), and the fast neutron removal cross section (FNRCS). The results show that the 55PbGe sample, which has the most PbO, has better gamma-ray attenuation and a low energy absorption buildup factor (EABF). This makes it a good choice option for locations requiring compact but efficient radiation shielding. The 50PbGe sample, on the other hand, demonstrates effective neutron shielding capabilities, suggesting it may be suitable for applications requiring protection against both gamma and neutron exposure. Higher PbO content is linked to better radiation blocking, which supports the idea that lead germanate glasses could be used instead of traditional lead-based shielding materials. © IJCESEN.
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    The impact of chemical modifications on gamma-ray attenuation properties of some WO3-reinforced tellurite glasses
    (De Gruyter Poland Sp Z O O, 2023) ALMisned, Ghada; Rabaa, Elaf; Sen Baykal, Duygu; Ilik, Erkan; Kilic, Gokhan; Zakaly, Hesham M. H.; Ene, Antoaneta
    We report the role of the chemical modifications on various gamma-ray attenuation properties of four different tellurite glasses reinforced through WO3. The chemical compositions and glass densities are used in terms of determining some critical attenuation properties, such as linear and mass attenuation coefficients, half value layer, and effective atomic number values. Based on the rise in density, it was determined that the maximum concentration of WO3 also resulted in a significant change in the overall gamma-ray absorption properties, when all of the study's findings were examined. It was observed that the glass sample, in which TeO2 and WO3 were 40 mol%, had the highest density. It was found that this glass with the highest density has the highest linear attenuation coefficient and mass attenuation coefficient and the lowest half value layer among the four samples specified. This demonstrates that WO3 inclusion is a functional component that may be used in tellurium glasses and is a suitable material for situations requiring increased gamma-ray absorption properties.
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    Indirect effect of elevated pressure via the modulations of crystals intrinsic parameters on radiation shielding efficacy: A comparative study between two α-quartz homeotypes SiO2 and GeO2
    (Elsevier Ltd., 2025) Afaneh, F.; Al Omari, S.; ALMisned, Ghada; Tekin, Hüseyin Ozan; Khattari, Z.Y.
    This study investigates the indirect effects of elevated pressure on the radiation shielding competence of two α-quartz homeotypes, SiO2 and GeO2, by examining the modulations of their crystal intrinsic tetrahedral parameters. The study focuses on structural modifications and their correlations with radiation attenuation properties. The results show that both homeotypes exhibit energy-dependent mass attenuation coefficients (MAC) and linear attenuation coefficients (LAC). SiO2 demonstrates higher transparency to incident radiation compared to GeO2, with a relative difference in MAC values of 91% at 0.015 MeV, decreasing to 28% at 15 MeV. However, within the energy range of 0.4 < E < 4 MeV, SiO2 exhibits higher MAC values than GeO2, with the MAC of SiO2 surpassing GeO2 by 17% at 0.4 MeV. The pressure dependence of LAC values indicates that both SiO2 and GeO2 become more effective in attenuating radiation under higher pressure conditions. For instance, at 0.015 MeV, the LAC of GeO2 increased from 274.826 cm−1 at 0.001 GPa to 308.073 cm−1 at 5.57 GPa. GeO2 generally exhibits higher LAC values than SiO2 across the energy and pressure ranges studied. It can be concluded that the structural modifications induced by elevated pressure significantly enhance the radiation shielding capabilities of α-quartz homeotypes, particularly GeO2, making them promising candidates for advanced shielding materials in various high-radiation environments. © 2024 Elsevier Ltd
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