Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Güler, Ömer(32)
- Akkurt, Nevzat(27)
- Tekin, H.O.(27)
- ALMisned, Ghada(24)
- Gul, Muhammet(20)
- Yucesan, Melih(14)
- Xu, Qian(12)
- Baykal, Duygu Sen(11)
- Güler, Seval Hale(11)
- Taşgın, Yahya(10)
- Kavaz, E.(9)
- Kilic, G.(8)
- Zengin, Gokhan(8)
- Durmus, Hasan(7)
- Guler, Omer(7)
- Xiong, Yaxuan(7)
- Yılmaz, Demet(7)
- Özkul, İskender(7)
- Yayla, Nihal(6)
- Zhang, Hui(6)
- Alkarrani, Hessa(5)
- Baloglu, Ulas Baran(5)
- Celik, Erkan(5)
- Du, Yanping(5)
- Ilik, E.(5)
- Kanca, M. Sait(5)
- Kök, Mediha(5)
- Mahomoodally, Mohamad Fawzi(5)
- Ortiz-Barrios, Miguel(5)
- Qiang, Yujie(5)
- Yang, Gang(5)
- Zakaly, Hesham M.H.(5)
- Aghakhani, S.(4)
- Basgoz, Oykum(4)
- Birdogan, Selcuk(4)
- Caprioli, Giovanni(4)
- Etli, Serkan(4)
- Guler, Seval Hale(4)
- Kahraman, Gökhan(4)
- Liu, Lin(4)
Yayınlar
- MakaleYalnız künye2026Scopus SJRQ2Linking microstructural modifications of Ho2O3-doped borotellurite glasses to the enhancement of critical properties: Synthesis, structural, physical, and experimental Gamma-Ray and neutron transmissioncharacteristics
Kilic, G.; Ilik, E.; Kavaz, E.; Durmus, Hasan; Güler, Ömer; Birdogan, Selcuk; ALMisned, Ghada; Tekin, H.O.
This study investigates the effects of holmium oxide (Ho2O3) microparticle reinforcement on the structural, physical, and radiation shielding properties of borotellurite glasses with compositions ranging from 0 to 12 mol% Ho2O3. X-ray diffraction and TEM analyses confirmed the retention of amorphous structure across all samples, with localized short-range ordering observed at higher Ho contents. Glass density increased from 4.598 to 5.202 g/cm3 with increasing Ho2O3, while molar volume expanded from 27.94 to 30.61 cm3/mol, and oxygen packing density decreased from 0.605 to 0.551 g/cm3, indicating network expansion due to the substitution of lighter Li + ions by heavier Ho3+. Gamma-ray shielding properties significantly improved with Ho incorporation. At 81 keV, the linear attenuation coefficient increased from 8.33 to 13.70 cm−1, and the mass attenuation coefficient improved from 2.066 to 2.735 cm2/g. Moreover, effective atomic number rose from 44.9 to 52.5 and half-value layer decreased by 20.5% at 383 keV, and buildup factors dropped by up to 34% at 0.5 MeV. Neutron dose absorption improved, and the fast neutron removal cross-section increased from 0.1066 to 0.1113 cm−1. These results confirm that Ho2O3 contributes as a highly effective multifunctional dopant, significantly enhancing both gamma-ray and neutron shielding performance of borotellurite glasses, one of the most promising glass systems for advanced radiation protection applications.
AtıfScopus1OpenAlex1
İncele - MakaleYalnız künye2026Scopus SJRQ2Stratigraphy, mineralogy, paleodepositional environment, and diagenetic evolution of the Pülümür evaporites (Tunceli, Eastern Anatolia, Türkiye)
Us, Muhammed Sami
The gypsum member of the Balpayam Formation (GMoBF) in the Pülümür Kırmızıköprü Basin (PKB), Eastern Anatolia, records a complex evaporitic system shaped by episodic tectonism, volcanism, and fluctuating hydrological conditions. Stratigraphic logging, facies analysis, and systematic sampling from outcrops and quarries enabled a detailed assessment of the evaporite succession. Petrographic data reveal pervasive secondary gypsum textures, including porphyroblastic, alabastrine, laminated, brecciated, and satin-spar fabrics preserving relics of primary anhydrite and calcite. XRD and FIB-SEM-EDS analyses identify gypsum, anhydrite, celestine, dolomite, calcite, clay minerals, and minor siliciclastic, clarifying diagenetic pathways. Diagenesis initiated with early calcite and aragonite precipitation, followed by replacement by primary anhydrite and gypsum under elevated Mg2+/Ca2+ ratios and shallow burial. Later hydration, dehydration, and rehydration cycles produced secondary gypsum with distinctive microtextures and micro-hydration channels. The PKB reflects a dual depositional system: a shallow, low-energy, restricted lagoon dominated by massive-laminated gypsum, stromatolitic textures, and organic-rich layers, and a comparatively deeper open marine setting with laminated-banded gypsum and transported gypsum arenite-rudite facies. Chicken-wire gypsum and anhydrite nodules indicate synsedimentary to early diagenetic formation under hypersaline conditions. A schematic depositional model constrains the temporal and spatial evolution of diagenetic processes, highlighting the interaction among evaporite deposition, tectonic activity, and environmental fluctuations in the southern Neo-Tethys Ocean of Eastern Anatolia.
- MakaleYalnız künye2026Scopus SJRQ1Determination of microplastic contamination and phthalate ester migration in canned and frozen packaged seafood: A probabilistic human health risk assessment via Monte Carlo simulation
Macit, Arife; Köktürk, Mine; Serdar, Osman; Alak, Gonca
This research was designed to identify the levels of microplastics (MP) and phthalate esters (PAE) in canned and frozen packaged fish and to assess the human health risks associated with these pollutants. Analyses were carried out on a total of 25 sample groups, including 10 different canned tuna samples, 9 different packaged seafood products, and 6 different packaging materials. Microplastics were characterized and polymer identification was performed using μ-Raman and ATR-FTIR spectroscopy, while PAEs were determined by GC–MS/MS. The obtained data were used to calculate estimated daily intake (EDI), hazard index (HI), hazard quotient (HQ), and cancer risk (CR), and uncertainty was assessed using Monte Carlo simulation. The findings revealed that both microplastic and phthalate exposure were higher in the frozen fish group than in canned products. The highest MP concentrations were recorded in packaged Whiting B (0.73 ± 0.25 items/g) and oil-added canned tuna (0.57 ± 0.15 items/g). Regarding PAEs, while DEHP and DBP were generally prominent, significant peak concentrations of BBP and DNOP were also identified, reaching 1.91 ± 0.01 ppm for BBP in canned tuna with sunflower oil and 1.84 ± 0.01 ppm in packaged whiting. Furthermore, higher exposure was observed in males for most PAEs. HQ and HI values were below 1 (maximum HI: 1.57 × 10−2 for males consuming frozen seafood), while CR values remained within an acceptable range (4.74 × 10−7 to 3.49 × 10−6). In conclusion, health risks related to processed fish consumption appear generally low; however, processing and packaging may contribute to contamination and warrant further investigation.
- MakaleAçık Erişim2026Scopus SJRQ1Assessing interrelationships among circular economy implementation strategies
Ahmadi, Hadi Badri; Gul, Muhammet; Gupta, Himanshu; Yucesan, Melih; Liou, James J.H.
Strategies for implementing a circular economy (CE) are designed to enhance resource efficiency, minimize the consumption of raw materials, and decrease waste. Although many articles have investigated CE implementation strategies, research focusing on the interactions and interrelationships among these strategies remains scarce. To address this issue, this study develops an evaluation framework, with the aim of assessing the interactions among strategies for CE implementation in the context of the manufacturing sector of an emerging economy using Decomposed Fuzzy Decision-Making Trial and Evaluation Laboratory (DF-DEMATEL) methodology. The findings suggest that “Investment in green technology” is the most critical strategy and should receive the greatest attention for successfully implementing CE. This research helps industrial decision-makers and specialists to invest in the most critical strategies within their supply chains and move towards sustainable development.
- MakaleAçık Erişim2026Scopus SJRQ1Comparative and systematically analysis of the effects of single and high-entropy rare earth oxide additives on the some physical properties and radiation shielding properties of copper composites
Kanca, Muhammed Sait; Yılmaz, Demet; Tasgın, Yahya; Kök, Mediha; Güler, Seval Hale
In this study, the effects of rare earth oxides (Gd₂O₃, La₂O₃, Eu₂O₃, Pr₂O₃, Dy₂O₃, and Y₂O₃) and high-entropy oxide (GdLaEuPrDyY)₂O₃ additives on the structural, mechanical, and radiation shielding properties of copper matrix composites were investigated. XRD and SEM-EDS analyses showed that the high-entropy oxide successfully formed in a single-phase bixbyite structure after mechanical alloying and was homogeneously distributed within the copper matrix. The rare earth oxide additive significantly reduced the crystal grain size of the Cu matrix and improved its mechanical properties. Specifically, the microhardness value reached 68.3 Hv in the composite with 20% high-entropy oxide additive, representing an increase of approximately 111% compared to pure copper (32.3 Hv). Gamma shielding results showed that the rare earth oxide additive significantly increased the photon attenuation capacity. Specifically, at 242 keV energy, the Dy₂O₃ additive increased the MAC value from 0.141 cm²/g to 0.246 cm²/g, providing a 74.5% improvement. The most important result is that the composite with 20% high-entropy oxide additive showed the highest shielding performance, achieving a MAC value of 0.278 cm²/g, which is significantly superior to pure copper. Furthermore, this composite exhibited the lowest HVL and MFP values, demonstrating the highest photon shielding efficiency. Neutron shielding analyses revealed that Gd₂O₃ and high-entropy oxide additives, in particular, increased thermal neutron attenuation performance to approximately 100%. These results demonstrate that high-entropy oxide additives provide a stronger impact compared to single oxide additives, offering superior performance in both gamma and neutron shielding. Consequently, copper composites doped with (GdLaEuPrDyY)₂O₃ stand out as promising alternative shielding materials for nuclear facilities, radiation protection systems, and advanced engineering applications due to their high shielding efficiency, improved mechanical properties, and non-toxic composition.
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ2Physical and gamma-ray shielding characteristics of Copper Matrix Refractory High Entropy Alloy Reinforced Composite: an extensive experimental and computational approach
Kuluöztürk, Zehra Nur; Kuluöztürk, Muhammed Fatih; Güler, Seval Hale; Doğru, Mahmut; Güler, Ömer
Refractory High Entropy Alloys (RHEAs) have become an attractive alternative for radiation shielding applications due to their high mechanical strength, thermal resistance, structural stability, and compositional diversity. In this study, Cu-based composites containing 0–20 wt% RHEAs were prepared, and the crystal structure, morphological properties, and radiation shielding performance of the synthesized Cu-RHEA were investigated experimentally and theoretically. Measurements were performed using a NaI(Tl) detector system with point sources of 133Ba, 137Cs, 22Na and 60Co emitting gamma energies in the range of 0.356–1.333 MeV. In addition, theoretical calculations were carried out using the FLUKA and Phy-X/PSD, showing good agreement with the experimental data. Linear attenuation coefficient (LAC) values were found to decrease with increasing photon energy and to increase with increasing RHEA content. In the 0.356–1.333 MeV energy range, the experimental LAC values ranged from 0.7599 to 0.3818 cm−1 for Cu-RHEA0 and from 0.9594 to 0.4221 cm−1 for Cu-RHEA20. At 0.662 MeV, the LAC value increased from 0.5426 cm−1 for Cu-RHEA0 to 0.6183 cm−1 for Cu-RHEA20. In terms of half-value layer (HVL), the Cu-RHEA20 sample exhibited a value of 0.729 cm at 0.356 MeV, approximately 20% lower than the 0.912 cm value of Cu-RHEA0. Compared with conventional shielding materials reported in the literature, the Cu-RHEA20 sample reached a maximum mass attenuation coefficient (MAC) of 76.279 cm2⋅g−1 at 0.015 MeV, demonstrating clear superiority over ordinary concrete with a value of 7.079 cm2⋅g−1. These findings demonstrate that increasing RHEA content improves gamma-ray attenuation performance, highlighting Cu-RHEA20 as a promising next-generation shielding material.
- MakaleYalnız künye2026Scopus SJRQ1Mineralogical and geochemical controls on Co-V-Pt-Ni enrichment in manganese mineralization: evidence from the Dilli deposit, Eastern Türkiye
Gücer, Mehmet Ali; Çimen, Okay; Aktağ, Alican; Keskin, Serdar
The growing demand for critical minerals driven by the global energy transition and advanced technologies highlights the importance of unconventional metal reservoirs. This study investigates the Ni-, Co-, V-, and Pt-enriched Dilli manganese deposit (Kemaliye-Erzincan, Eastern Türkiye) to constrain the mineralogical, geochemical, and genetic controls on critical metal enrichment in Mn oxide mineralization. An integrated approach combining field observations, petrography, X-ray diffraction (XRD), whole-rock geochemistry, mineral chemistry, and stable C-O isotope analysis was applied to better understand the potential origin of critical mineral enrichments. The mineralization is dominated by Mn4+-bearing oxides, principally pyrolusite and hollandite, accompanied by minor rhodochrosite. High MnO (39-64 wt%) and very low Al2O3 and Fe2O3 contents indicate chemical precipitation with negligible detrital input. Discrimination diagrams and trace-element systematics consistently support a structurally controlled hydrothermal origin. Chondrite-normalized REE patterns display low total REE and very low Nd contents comparable to typical hydrothermal deposits, whereas neutral to slightly positive Ce anomalies and non-chondritic Y/Ho ratios suggest limited oxidative interaction with surface-derived fluids rather than primary marine hydrogenetic growth. Stable C–O isotope compositions of co-genetic calcite are inconsistent with a purely marine depositional environment and indicate precipitation from low-to moderate-temperature hydrothermal fluids. Mineral chemistry reveals strong phase-specific partitioning: hollandite preferentially incorporates V and Ba, whereas pyrolusite is enriched in Ni. Cobalt occurs in both phases, whereas Pt may also be present in both Mn oxide phases, suggesting that trace-element distribution is influenced by both crystallochemical and physicochemical controls. The enrichment of Ni, Co, and Pt is most plausibly linked to hydrothermal fluid circulation through ultramafic units, which likely acted as the primary metal source prior to precipitation. The Dilli deposit thus represents a structurally controlled hydrothermal Mn system enriched in critical metals, emphasizing the exploration relevance of Mn oxide mineral chemistry in identifying alternative sources of critical metals in Türkiye.
- MakaleYalnız künye2026Scopus SJRQ2High-entropy rare-earth tungstate (PrEuYLaSm)2(WO4)3: Synthesis, physical, structural evolution and shielding properties
Durmus, Hasan; Özkul, İskender; Güler, Ömer; Güler, Seval Hale; Baykal, Duygu Sen; ALMisned, Ghada; Tekin, H.O.
In this study, a novel high-entropy rare-earth tungstate, (PrEuYLaSm)2(WO4)3, was synthesized by high-energy ball milling followed by calcination, and its structural, microstructural, thermal, gamma-ray, and neutron shielding properties were systematically investigated. X-ray diffraction results revealed that ball milling induced partial amorphization of the initial oxide mixture, while calcination at 1100 °C promoted the formation of a single-phase monoclinic A2W3O12-type structure without detectable secondary phases. SEM-EDS mapping showed the homogeneous distribution of Pr, Eu, Y, La, Sm, W, and O throughout the synthesized material. Differential thermal analysis showed sequential desorption, crystallization, and structural ordering processes, together with the absence of sharp decomposition up to 1100 °C, indicating good thermal stability. Radiation shielding evaluation demonstrated that the synthesized high-entropy tungstate exhibited strong gamma-ray attenuation performance, with high mass attenuation coefficient values, low half-value layer values, and stable effective atomic number behaviour over a wide photon energy range. Although some individual oxides showed superior performance at specific energies, the high-entropy composition provided a more balanced shielding response overall. In neutron shielding, the material showed competitive fast neutron removal capability among oxide systems. It can be concluded that the multifunctional potential of (PrEuYLaSm)2(WO4)3 for competitive high-temperature and radiation shielding applications.
- MakaleAçık Erişim2026Scopus SJRQ1Influence of apple pomace and asparaginase on acrylamide levels in cookies and behavior during simulated gastric digestion: risk assessment perspectives
Sevim, Sumeyra; Macit, Arife; Farıa, Miguel A.; Viegas, Olga; Cunha, Sara C.; Kizil, Mevlude; Ferreira, Isabel M.P.L.V.O.
Cookies are widely consumed baked products; however, their contribution to dietary acrylamide (ACR) intake raises increasing health concerns. This study investigated the effects of apple pomace addition and asparaginase treatment on ACR levels in cookies, the fate of ACR during simulated gastric digestion using the INFOGEST semi-dynamic model, and the associated health risks of ACR exposure from cookie consumption. Risk assessment was conducted for adults (18–65 years) and children (3–10 years) using Monte Carlo simulation. Three formulations were evaluated: a control cookie, a cookie in which wheat flour was partially replaced with apple pomace, and a cookie containing asparaginase. Cookies formulated with apple pomace contained significantly lower ACR levels than the control (132 ± 8 μg/kg vs. 215 ± 11 μg/kg; p < 0.05), although the reduction was less pronounced than in cookies containing asparaginase (65 ± 14 μg/kg). During gastric digestion, ACR exhibited formulation-dependent release kinetics. Nevertheless, the total ACR released at the end of digestion was similar for control and pomace cookies, likely due to additional ACR formation in the stomach, despite differences in release patterns throughout digestion. Margin of Exposure (MOE) values for children remained well below 10,000, indicating a potential carcinogenic risk, although reductions of up to 59% were observed for control and pomace cookies after digestion. Target Hazard Quotient (THQ) values showed a slight increase after digestion in both age groups but remained below 1, suggesting no concern for chronic toxicity. Control cookies indicated a potential carcinogenic risk for children (ILCR = 1.56 × 10−4), whereas pomace and asparaginase formulations reduced this risk (ILCR = 9.59 × 10−5 and 4.72 × 10−5, respectively). However, simulated gastric digestion increased ILCR values for both control and pomace cookies (2.24 × 10−4 and 2.33 × 10−4, respectively). These findings indicate that dietary exposure to ACR cannot be assessed solely based on its concentration in food, and that digestive kinetics should be incorporated into health risk assessment.
- MakaleAçık Erişim2026Scopus SJRQ1Structural and radiation shielding properties of high-entropy rare-earth oxide-doped borosilicate glass
Güler, Ömer; Yılmaz, Demet; Kanca, Muhammed Sait; Kök, Mediha; Taşgın, Yahya
In this study, the incorporation of a high-entropy rare-earth oxide, (GdLaEuPrDyY)2O3 (RE-HEO), into a borosilicate glass matrix was investigated with the aim of improving radiation shielding performance while preserving the structural integrity of the glass. The RE-HEO was first synthesized by high-energy mechanical alloying and then introduced into the glass system at concentrations ranging from 0 to 8 wt% using a conventional melt-quenching process. The structural and microstructural properties of the prepared samples were examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy combined with energy-dispersive spectroscopy (SEM–EDS). The analyses confirmed that the amorphous nature of the borosilicate glass was maintained and that the rare-earth elements were homogeneously distributed within the matrix. The radiation shielding performance was evaluated experimentally using Am-241, Ba-133, and Ra-226 gamma sources, and supported by theoretical calculations of key parameters including mass attenuation coefficient (MAC), half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factor (EBF), and fast neutron removal cross-section (ΣR). The results showed that increasing RE-HEO content leads to a noticeable improvement in gamma-ray attenuation. In particular, the sample containing 8 wt% RE-HEO exhibited a MAC value of 0.131 cm2/g and an HVL of 2.03 cm at 356 keV, indicating shielding performance comparable to that of conventional lead-containing glasses. In addition, irradiation tests performed using a Co-60 gamma source revealed that the amorphous structure remains stable after exposure. Overall, the findings suggest that RE-HEO-doped borosilicate glass can be considered a promising lead-free alternative for radiation shielding applications.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ2Radiation shielding performance of CeO2-reinforced ternary nanocomposites based on biodegradable polymers and waste-derived polystyrene
Pekdemir, Mustafa Ersin; Yilmaz, Demet; Selçuk Pekdemir, Sibel; Gülhan, Aleyna; Yalçin Kuzu, Serpil; Altun, Sedanur; Taşgin, Yahya
The development of sustainable polymer-based materials for radiation shielding has attracted increasing interest, particularly for lightweight and flexible applications. In this study, ternary nanocomposites based on poly (hydroxyalkanoate) (PHA), poly (ε-caprolactone) (PCL), and polystyrene (PS) were prepared and reinforced with cerium oxide (CeO2) nanoparticles (5–15 wt%) to enhance radiation shielding performance. Structural characterization confirmed the preservation of polymer chemical structures and the successful incorporation of crystalline CeO2, while SEM observations revealed a relatively homogeneous nanoparticle dispersion within the ternary matrix, particularly at intermediate filler loadings. Thermal analysis demonstrated enhanced thermal stability with increasing CeO2 content, as evidenced by an increase in residual mass from 0.42% for the neat blend to 11.21% for the nanocomposite containing 15 wt% CeO2, along with a shift of degradation onset temperatures toward higher values. Photon shielding performance was experimentally evaluated in the energy range of 13.37–59.54 keV. The incorporation of 15 wt% CeO2 increased the mass attenuation coefficient (MAC) from 1.277 to 12.366 cm2 g−1 at 13.37 keV, corresponding to an approximately ninefold enhancement, while significantly reducing the half-value layer (HVL) and mean free path (MFP). Neutron shielding analysis showed a slight decrease in thermal neutron attenuation due to hydrogen dilution within the polymer matrix, whereas fast neutron attenuation and neutron removal cross sections exhibited only minor variations; the fast neutron removal cross section increased modestly from 0.1014 to 0.1047 cm−1 with 15 wt% CeO2 addition. Overall, the results highlight clear structure–property–performance relationships in CeO2-reinforced PHA/PCL/PS nanocomposites, demonstrating their potential as lightweight radiation shielding materials for low energy protection with improved thermal stability and shielding efficiency.
AtıfScopus2OpenAlex1
İncele - MakaleAçık Erişim2026Scopus SJRQ1Investigation of the structural, thermal and radiation shielding properties of (Er0.2Yb0.2Sm0.2La0.2Eu0.2)2Zr2O7 high entropy oxide reinforced tin matrix composite
Güler, Ömer; Yılmaz, Demet; Kanca, M. Sait; Kök, Mediha; Güler, Seval Hale; Taşgın, Yahya
This study investigates the structural, thermal, and radiation shielding properties of (Er0.2Yb0.2Sm0.2La0.2Eu0.2)2Zr2O7 high entropy oxide (HEO) reinforced tin (Sn) matrix composites. In the first stage of the study, HEO powders were synthesized by grinding at 350 rpm for 30 h using a solid-state method with mechanical alloying assistance, and then calcining at 1100 °C for 8 h. In the second stage, composites were produced by mixing HEO-reinforced Sn matrix materials containing 1%, 5%, and 10% reinforcement, pelleting them under 200 MPa pressure, and then sintering them at 300 °C for 3 h. In the first stage of the study, (Er0.2Yb0.2Sm0.2La0.2Eu0.2)2Zr2O7 HEO powders were synthesized using a mechanical alloying-assisted solid-state route. In the second stage, HEO-reinforced Sn matrix composites containing 1 wt%, 5 wt%, and 10 wt% reinforcement were produced. The phase formation and crystallographic structure of the synthesized powders and composites were characterized using X-ray diffraction. Thermal behavior and phase stability were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The thermal analysis results revealed dehydration and structural stabilization processes at intermediate temperatures, while crystallization of the HEO phase was observed at elevated temperatures. In addition, oxidation behavior of the Sn matrix composites was evaluated, showing that the presence of HEO particles significantly suppresses mass gain during high-temperature oxidation, indicating improved thermal stability. Finally, the radiation shielding performance of the samples was experimentally evaluated within the photon energy range of 59.54–609.2 keV using Am-241, Ba-133, and Ra-226 radioactive sources together with a Ultra-Low Energy Germanium (ULEGe) detector. The results demonstrate that the incorporation of HEO particles leads to minor, energy-dependent variations in the radiation attenuation capability of the tin matrix, influenced by the presence of high atomic number rare-earth elements and modified microstructural characteristics. The gamma radiation protection coefficient (RPC) values indicate strong attenuation in the low photon energy region, decreasing to approximately 16–19% at 609.3 keV. Moreover, the measured neutron equivalent dose rates increase from 0.054 µSv/h for pure Sn to 0.285 µSv/h for the Sn–10%HEO composite, indicating that HEO incorporation modifies the neutron interaction behavior of the Sn matrix composites.
- MakaleYalnız künye2026Scopus SJRQ2Alloy-to-oxide transformation of a spinel-structured (Fe30Cr30Mn20Ni10V10)3O4 high-entropy alloy-oxide via mechanical alloying: Synthesis, phase stability, multivalent surface states, and radiation attenuation behaviour
Güler, Ömer; Güler, Seval Hale; Özkul, İskender; Baykal, Duygu Sen; Tekin, H.O.; ALMisned, Ghada
A spinel-structured high-entropy alloy-oxide (HEAO) with the nominal composition (Fe30Cr30Mn20Ni10V10)3O4 was synthesized via mechanical alloying followed by thermo-mechanical oxidation X-ray diffraction indicated the formation of a predominantly spinel-type cubic oxide phase after oxidation, with the observed reflections being consistent with the Fd-3m spinel structure, while SEM-EDS mapping showed a homogeneous cation distribution at the examined scale. XPS analysis revealed mixed valence states of Fe2+/Fe3+, Cr3+/Cr4+, Mn3+/Mn4+, Ni2+/Ni3+, and V4+/V5+. Thermodynamic parameters supported phase stability, with ΔSmix = 12.51 J K−1·mol−1 and Ω = 2.68. Gamma-ray attenuation properties were evaluated over 0.015-15 MeV. The linear attenuation coefficient decreased from 193.685 cm−1 at 0.015 MeV to 0.309 cm−1 at 1 MeV and stabilized near 0.137 cm−1 at 15 MeV. Correspondingly, the half value layer increased from 0.004 cm to 5.068 cm across the same energy range. The effective atomic number decreased from 24.58 at 0.015 MeV to approximately 15.37 at 1 MeV, followed by a moderate increase to 17.71 at 15 MeV. Comparative analysis with commercial stainless steel, titanium alloys, nickel-based superalloys, ferro-boron systems, and lightweight entropy alloys demonstrated that the synthesized HEAO exhibits intermediate yet stable attenuation performance, positioning it between low-density Al-based systems and high-density Ni-rich alloys. It can be concluded that the alloy-to-oxide strategy enables the production of a structurally stable spinel HEAO with consistent and competitive gamma-ray attenuation behaviour across a broad photon energy spectrum.
AtıfScopus1OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ1Flexural response prediction of C-shaped concrete-filled composite plate shear walls (C-PSW/CF) using response surface methodology
Polat, Erkan
Concrete-filled composite plate shear walls (C-PSW/CF) are an emerging prefabricated structural system that combines high strength, stiffness, and constructability for use in high-rise and seismic applications. Conventional plastic-theory-based flexural models originally developed for planar walls are intended only to estimate peak flexural strength; however, they cannot adequately capture several mechanisms governing the behavior of C-shaped sections, including concrete confinement, plate local buckling, von Mises stress interaction, and shear-lag effects. Moreover, no analytical formulations are currently available for predicting the full monotonic flexural response of such walls. This study develops a surrogate-based modeling framework that integrates high-fidelity finite element (FE) simulations with Response Surface Methodology (RSM) to predict the monotonic flexural response and yield moment capacity of C-shaped C-PSW/CF walls. A validated three-dimensional FE model (FEM) was used to simulate 77 wall configurations generated through a Central Composite Design (CCD) by varying six geometric and material parameters. Second-order RSM equations were derived to estimate moment capacity across drift ratios up to ±4% in both loading directions and to predict yield moments corresponding to the onset of web and flange plate yielding. The developed models show high predictive accuracy (R² > 0.95) and successfully capture nonlinear parameter interactions among section geometry, reinforcement ratio, and steel yield strength. Compared with nonlinear FE simulations, the RSM equations enable rapid prediction of wall capacity using explicit closed-form expressions, providing a computationally efficient tool for performance-based design and parametric evaluation of prefabricated composite wall systems.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2025Scopus SJRQ1Mechanisms of hardness enhancement in CrB2 thin films with varying VB2 concentrations
Yüzüak, G.D.; Tomakin, M.
Transition metal borides are well-known for their high hardness, excellent wear resistance, chemical inertness, and electrical conductivity, making them promising for a wide range of applications. Understanding the interconnections between material structure, composition, and mechanical properties is essential for designing and synthesizing effective coatings. This study systematically investigates the structural and mechanical properties of CrB₂ thin films with varying concentrations of VB₂ (0–10 wt%), focusing on structure, hardness, elastic behavior and deformation characteristics mechanisms through atomic force microscopy and nanoindentation measurements. The results show that increasing VB₂ content leads to the formation of island cluster structures, which significantly strengthens atomic bonds and, in turn, enhances the hardness of the thin films. As particle size decreases, the higher proportion of surface atoms and increased surface energy have a more pronounced effect on the mechanical properties. In particular, the addition of VB₂ up to 10 wt% in CrB₂ thin films results in a marked improvement in superhard properties. 26 % increase in hardness value is also influenced directly by the changes in Young's modulus and Poisson's ratio that depend on the VB₂ concentration.
AtıfScopus5WoS5OpenAlex6İncele - MakaleYalnız künye2025Scopus SJRQ1Impact of controlled oxidation and incorporation of high entropy rare-earth alloys (HE-REAs) on the structural, physical, optical, and radiation shielding performance of zinc-borate glasses
Ilik, E.; Guler, Seval Hale; Güler, Ömer; Durmus, Hasan; Kavaz, E.; Birdogan, Selcuk; ALMisned, Ghada; Kilic, G.; Tekin, H.O.
This study investigates the influence of high entropy oxide (HEO) and high entropy alloy oxide (HEAO) dopants on the structural, optical, and radiation shielding properties of zinc-borate glasses. Two synthesis routes were employed through direct mechanical alloying of five rare-earth oxides such as Sm2O3, Ho2O3, Er2O3, Yb2O3, Gd2O3 to form (SmHoErYbGd)2O3 HEO, and mechanical alloying of the corresponding rare-earth metals followed by oxidation to produce HEAO of the same elemental composition. The central hypothesis proposed that the dopant structure and oxygen coordination, not just elemental presence, critically influence the on characteristic behaviors in terms of radiation attenuation. Structural analyses confirmed that HEAO-doped glasses exhibit more homogeneous, amorphous networks. Optical characterizations revealed red-shifted absorption edges and lower Urbach energies in HEAO samples, indicating reduced disorder. HEAO-doped glasses showed superior gamma-ray shielding, with higher linear attenuation coefficients and lower half-value layers than HEO or undoped samples. Most notably, HEAO glass achieved the highest fast neutron removal cross-section, surpassing water, graphite, and B4C. These findings demonstrate that rare-earth high entropy alloy oxides offer a structurally optimized pathway for designing next-generation multifunctional glasses for radiation-related applications.
AtıfScopus9OpenAlex8İncele - MakaleYalnız künye2025Scopus SJRQ2Elastic modulus, nuclear radiation transmission properties of Fe-based/contained novel alloys for critical radiation applications
ALMisned, Ghada; Susoy, Gulfem; Baykal, Duygu Sen; Alkarrani, Hessa; Güler, Ömer; Issa, Shams A.M.; Zakaly, Hesham M.H.; Tekin, H.O.
This study explores the gamma-ray and neutron shielding properties and mechanical performance of eight Fe-based alloys with varying elemental compositions and densities. Different parameters such as mass attenuation coefficients, linear attenuation coefficients, half-value layer, tenth-value layer, mean free path, fast neutron removal cross-sections, transmission factors were analysed using PHITS and Phy-X/PSD codes. Moreover, elastic modulus values were calculated for each alloy sample. Our results reveal that the S9 alloy, with high density and tungsten contribution, exhibited superior shielding and mechanical properties, achieving the lowest TF, HVL, and TVL values. In contrast, the low-density S1 alloy performed weakest, reflecting its lighter elemental composition. Intermediate alloys like MAR-302 and Cupero-Nickel showed balanced performance, suitable for moderate shielding needs. Strong correlations between elemental compositions, particularly high-Z elements like tungsten and boron, and shielding efficiency were observed. It can be concluded that optimizing elemental composition and density is critical for designing alloys with enhanced multifunctional properties.
AtıfScopus3OpenAlex2İncele - MakaleAçık Erişim2025Scopus SJRQ1Blending effects of boron carbide and lanthanum(III) oxide reinforcements on the structural, physical, mechanical, and radiation shielding properties of 316L-stainless steel composites for nuclear applications
ALMisned, Ghada; Yayla, Nihal; Albayrak, M.Gökhan; Güler, Ömer; Baykal, Duygu Sen; Alkarrani, Hessa; Tekin, H.O.
Four composite samples were fabricated, maintaining 10 % B4C and varying La2O3 content from 0 % to 20 %. X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDX) analyses confirmed the successful incorporation of reinforcements, preserving the austenitic structure of 316L-SS. Elastic modulus calculations revealed a gradual reduction from 225.0 GPa to 215.0 GPa with increasing La2O3 due to clustering and reduced homogeneity. Gamma-ray shielding properties demonstrated significant improvements, particularly at low and intermediate photon energies, with Sample 4 with 20 % La2O3 addition, achieving a 13.6 % higher linear attenuation coefficients (LAC) at 0.015 MeV. Neutron shielding highlighted Sample 4 as one of the most effective materials, outperforming conventional alloys. This study demonstrates the potential of 316L Stainless-Steel (316L-SS) + B4C + La2O3 composites as multifunctional materials for radiation-intensive applications, offering superior attenuation and structural stability. It can be concluded that optimization of reinforcement distribution would play an important role in balancing mechanical and shielding performance in next-generation nuclear materials.
AtıfScopus5OpenAlex5İncele - MakaleYalnız künye2025Scopus SJRQ2Comprehensive performance assessment of Bi- and Pb-based alloys for enhanced Gamma-Ray and neutron shielding applications
ALMisned, Ghada; Susoy, Gulfem; Baykal, Duygu Sen; Kilic, G.; Güler, Ömer; Tekin, H.O.
This comprehensive study investigates the radiation attenuation properties of various bismuth (Bi) and lead (Pb) based alloys, with a focus on identifying superior shielding materials for nuclear safety and industrial radiation protection. The research encompasses an in-depth analysis of seven alloys, namely GTSB5, Sn%40Bi, Bi50Sn50, A1, PbAl-4, Safe Alloy, and P1, assessing their efficacy in gamma-ray and neutron attenuation. Utilizing some computational tools, various parameters such as mass and linear attenuation coefficients, half and tenth value layer values, effective atomic and electron numbers, buildup factors, and transmission values were evaluated. Our findings highlight Alloy P1's outstanding performance, attributed to its high density (11.05 g/cm3) and optimized elemental composition, including Silver (Ag). In addition, P1 demonstrates exceptional gamma-ray attenuation across multiple energy spectra and superior neutron shielding capabilities, evidenced by its significant fast neutron removal cross-section (∑R, 0.12003 1/cm). The study revealed that the addition of Ag enhances the photon and beta particle absorption capacity, positioning P1 as a promising material in radiation shielding applications. The correlations between alloy density and gamma-ray shielding properties were particularly notable, with P1's density contributing to its enhanced attenuation capabilities. Furthermore, P1's lower half value layers (1.14469 cm) and tenth value layers (3.80256 cm) at 15 MeV indicate its efficiency in reducing radiation intensity with minimal material thickness.
AtıfScopus3OpenAlex3İncele - MakaleYayıncıda açık erişim2025Scopus SJRQ1Experimental analysis of a double-slope solar still integrated with parabolic trough solar collector using nanofluid
Tuğan, Volkan; İnallı, Mustafa; Işık, Erdem
The use of solar energy in the treatment of saline water offers a sustainable and low-cost solution to the increasing global fresh water demand. In this direction, solar still systems separate water vapor from saline water by directly using solar radiation and then condense it to obtain pure water. However, their fresh water productivity is relatively low. Therefore, in this study, the fresh water productivity and thermal efficiency of the double slope solar distillation unit integrated with parabolic trough solar collector, which operates completely on solar energy, were investigated experimentally. In addition, the effect of water-based nanofluid containing multi-walled carbon nanotubes on the performance of the solar still was investigated. All the stills produced were compared in terms of fresh water productivity and thermal efficiency. According to the results obtained from the study, the highest daily productivity was found to be 1963.8 g/m2/day, 2008.5 g/m2/day, 2592.0 g/m2/day and 2937.6 g/m2/day for SSSS, DSSS, PTSC integrated DSSS and both NF and PTSC integrated DSSS, respectively. It was observed that the daily productivity of DSSS, DSSS with integrated PTSC, and DSSS with both PTSC and NF were 6.6 %, 42.2 %, and 49.6 % higher than SSSS, respectively. Additionally, it was observed that the thermal efficiency of DSSS using PTSC and NF was lower compared to SSSS due to its larger system area.
AtıfScopus13WoS8OpenAlex10İncele