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 künye2024Scopus SJRQ1The effect of high entropy oxide on radiation shielding parameters of erbium oxide doped glasses
Kanca, M. Sait; Taşgın, Yahya; Yılmaz, Demet; Pathman, Abdul Fatah; Güler, Ömer
High-entropy materials are one of the most studied topics in recent years due to the extraordinary properties they exhibit. High entropy oxide (HEO) is a group of materials that have been studied for different applications. However, the effects of HEOs on the radiation properties of glasses are not well known. In this study, the structural, radiation and neutron shielding properties of SiO2 glass systems doped erbium oxide reinforced with refractory high entropy oxide (RHEO) with the formula TiMoNbTaWZrO11 were investigated. RHEAs used in the study were produced and characterized in our laboratory. Then, they were added to the glass samples at different rates together with Erbium oxide. As a result of SEM-EDS and XRD analyses, it was determined that the additives were distributed very homogeneously on the glass. The composition of glass systems is [95SiO2+(5-x)Er2O3+x TiMoNbTaWZrO11], where (x = 0, 0.5, 1 and 2 %, mol). The linear and mass attenuation coefficients (LAC and MAC), mean free path (MFP), half-value layer (HVL) and effective atomic numbers (Zeff) and effective electron density (Nel) of the glass structures were experimentally measured at the energy region of 53.16–661.62 keV. Also, the equivalent dose rates due to fast neutrons absorption were measured by using an 241Am–Be fast neutron source. Exposure buildup factor (EBF) and fast neutron removal cross section (ΣR) were theoretically determined. The proton and alpha shielding parameters of glasses were calculated. It is observed that glasses containing higher amounts of refractory high entropy oxide, within the SiO2–Er2O3 composition, demonstrated enhanced capabilities for shielding against radiation and neutrons.
AtıfScopus15WoS15OpenAlex17
İncele - MakaleYalnız künye2024Scopus SJRQ1Nutrification and fat reduction of deep-fried protein isolates
Erol, Nida Demirtas; Cakli, Sukran; Szymczak, Mariusz; Shen, Cangliang; Matak, Kristen E.; Jaczynski, Jacek
Deep-fried (DF) foods are considered nutritionally-inferior due to increased fat content, although they are popular with consumers due to desirable sensory characteristics. This study attempted to reduce fat of DF surimi, DF fish-protein-isolate (FPI), and DF chicken-protein-isolate (CPI) by pre-baking or pre-roasting. Surimi, FPI, and CPI were also nutrified with ω-3-rich oil, fiber, and KCl-based salt substitute. Pre-baking decreased (p < 0.05) fat content, while pre-roasting increased (p < 0.05) it. Pre-baking resulted in less (p < 0.05) changes to cook loss, moisture loss, expressible moisture, water-holding-capacity, whiteness, and texture when compared to pre-roasting. Pre-baking also better maintained ω-3 PUFAs concentration than pre-roasting, resulting in higher (p < 0.05) concentration of α-linolenic (ALA, 18:3ω3), eicosapentaenoic (EPA, 20:5ω3), and docosahexaenoic (DHA, 22:6ω3) FAs as well as unsaturated FAs and total ω-3 FAs in DF surimi, DF FPI, and DF CPI. Pre-baking in combination with nutrification using ω-3 PUFAs improved nutritional value of DF foods, while causing minimal quality changes.
AtıfScopus3WoS3OpenAlex3
İncele - DüzeltmeYalnız künye2024Scopus SJRQ1Retraction notice to “Cooling of non-sloped, positively sloped, and negatively sloped arrangements of Li-ion batteries with a phase change material connected to a solar system” [J. Energy Storage 52 Part B (2022) 104808] (Journal of Energy Storage (2022) 52(PB), (S2352152X22008179), (10.1016/j.est.2022.104808))
Akkurt, Nevzat; Aghakhani, S.; Mahmoud, Mustafa Z.; Abdelrahman, Anas
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). Please note that an Expression of Concern has previously been published to alert readers to an ongoing investigation into this paper. This retraction supersedes the Expression of Concern. This article has been retracted at the request of the editor. In investigating concerns brought up regarding the article, the editor reached out to the authors for an explanation. Furthermore, the editor discovered suspicious changes in authorship between the original submission and the revised version of this paper. In summary, the author names Nevzat Akkurt (new first author), Mustafa Z. Mahmoud and Anas Abdelrahman were added to the revised paper without explanation and without the exceptional approval by the editor, which is contrary to the journal policy on changes to authorship. The authors failed to provide a satisfactory explanation to the above points. The editor therefore feels that the findings of the manuscript cannot be relied upon and that the article needs to be retracted.
- MakaleYayıncıda açık erişim2024Scopus SJRQ1Photonic device application of a self-driven MXene based nanocomposite
Demirelli, Kadir; Dere, Ayşegül; Barım, Esra; Tuncer, Hülya; Yakuphanoğlu, Fahrettin
MXene based ternary composite photonic device was fabricated and characterized for the detection of different illuminations. The single chain polymer-cobalt phthallocyanine (SCP-CoPc) carrying metallised pthalocyanine macro ring was used as a polymer for the preparation of ternary composite. The Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX) were used to differentiate MXene/ZnO/SCP-CoPc composite prepared. The presence of Ti, C, O, Zn and Co elements in the structure of the composite was confirmed by EDX. The electrical properties of planar interdigital coated MXene/ZnO/SCP-CoPc (1:1:1 by wt) were investigated for photovoltaic application. The photo-generated carriers contribute to the current flow, and the linear photoconductivity behaviour in current measurements with different illuminations such as 20, 40, 60, 80 and 100 mW/cm2 indicates the possible photo device use of MXene/ZnO/SCP-CoPc nanocomposite. The photocurrent increased from 20 mA/cm2 to 100 mA/cm2 with the light intensity at 0.5 V was tuned from 28 to 280 μA. The forbidden energy gap (Eg) value of the MXene/ZnO/SCP-CoPc ternary composite from optical measurements was found to be 2.36 eV. Experimental results showed that the presence of SCP-CoPc and ZnO (zinc oxide) in the ternary nanocomposite increased the ε' and ε" values of MXene. The ε′ and ε″ of the ternary composite is 13.0, 26217 at 1 kHz and room temperature, respectively. The current-time results suggest that MXene based ternary composite photonic device is a self driven photodevice as the device can detect light without any external voltage bias.
AtıfScopus6OpenAlex6İncele - MakaleYalnız künye2024Scopus SJRQ1Synthesis, characterization and application of cross-linked functional terpolymer through epoxy group as sorbent for extraction of cadmium from waters and foods: Multivariate optimization
Yılmaz, Ersen; Boztuğ, Ali; Ul Haq, Hameed; Boczkaj, Grzegorz; Altunay, Nail
The purpose of this study was to develop a selective sorbent for cadmium ions (Cd(II)) enrichment in orbital shaker assisted solid phase microextraction (OS-SPME) from different aqueous and food samples. A maleic anhydride-styrene-glycidyl methacrylate (MA-St-GMA) terpolymer was synthesized and characterized in detail. Experimental variables of sample preparation step were optimized using a central composite design (CCD). The final determination step was performed using flame atomic absorption spectroscopy (FAAS). The MA-St-GMA sorbent exhibited a high adsorption capacity (195.9 mg g−1) for the Cd(II) ion. The developed method under optimal conditions provides satisfactory performance and a significant improvement compared to other protocols available in the literature. The linear range and detection limit of the method is 0.1–130 ng mL−1 and 0.03 ng mL−1, respectively. The robustness, intraday/interday precision, selectivity, and accuracy of the method were investigated. To further validate the method, a dedicated series of analysis was performed using certified reference materials (CRMs). This part of the study confirmed the applicability of the method for routine analysis. The OS-SPME-FAAS method was validated using water and food samples. Relative standard deviations and recovery for real-world samples were in ranges 1.7–2.2 % and 95.5–98.5 %, respectively. As a result, the MA-St-GMA sorbent showed that it could quantitatively extract Cd(II) ions from aqueous solution.
AtıfScopus9WoS8OpenAlex9İncele - MakaleYalnız künye2024Scopus SJRQ1Assessment of short and long-term pozzolanic activity of natural pozzolans using machine learning approaches
Khatti, Jitendra; Polat, Berivan Yılmazer
This investigation introduces the optimal performance models for predicting the compressive strength (CS) and pozzolanic activity index (PAI) by comparing the machine learning models. The machine learning models, i.e., multilinear regression (MLR), support vector machine (SVM), gaussian process regression (GPR), decision tree (DT), random forest (RF), and gene expression programming (GEP) have been trained (TRN) and tested (TST) by 28 and 7 data points. For the first time, the SiO2, Al2O3, Fe2O3, SiO2 +Al2O3 +Fe2O3, reactive SiO2, Blaine specific surface area, and specific gravity have been used as input variables to compute the CS, and 28 days PAI (28PAI), and 90 days PAI (90PAI) of the natural pozzolans. The multicollinearity analysis showed the SiO2, Al2O3, Fe2O3, SiO2 +Al2O3 +Fe2O3, reactive SiO2, and specific gravity have problematic multicollinearity (variance inflation factor – VIF > 10). Therefore, the root mean square error (RMSE), mean absolute error (MAE), correlation coefficient (R), performance index (PI), and variance accounted for (VAF) metrics have been implemented to evaluate the model's performance and multicollinearity impact. From the comparison of models, it has been recorded that model GPR outperformed the MLR, SVM, DT, RF, and GEP models in predicting CS (PI = 1.29, VAF = 71.31, R = 0.8473, MAE = 0.9390 MPa), 28PAI (PI = 1.87, VAF = 94.88, R = 0.9744, MAE = 0.7295 %), and 90PAI (PI = 1.72, VAF = 88.11, R = 0.9393, MAE = 1.2444 %) in the TST phase, close to ideal values. The score, generalizability. Wilcoxon test, uncertainty analysis, Anderson-daring test, and accuracy metrics have confirmed the superiority of GPR models in predicting CS, 28PAI, and 90PAI of natural pozzolans.
AtıfScopus28WoS25OpenAlex28İncele - MakaleYalnız künye2024Scopus SJRQ1Radiation shielding properties of composites of TiZrNbHfTa refractory high entropy alloy reinforced with TiZrNbHfTaOx high-entropy oxide
Güler, Ömer; Yılmaz, Demet; Kanca, M. Sait; Edalati, Kaveh; Taşgın, Yahya
Radiation shielding materials play a critical role in advancing the next generation of nuclear reactors. Among these, high-entropy materials with refractory properties emerge as a new category for radiation shielding applications. This study introduces TiZrNbHfTa-TiZrNbHfTaOx composites tailored for such purposes. Initially, a TiZrNbHfTa refractory high-entropy alloy (RHEA) is synthesized via mechanical alloying, followed by the oxidation of the alloy to obtain its refractory high-entropy oxide (RHEO), TiZrNbHfTaOx. Composites are then prepared by blending 5%, 10%, and 20% weight fractions of RHEO with RHEA using mechanical alloying. Comparative analysis of shielding properties reveals a decrease in mass attenuation coefficient and effective atomic number with increasing RHEO content. While RHEA exhibits superior shielding performance against gamma photons and neutrons, the composite containing 20% RHEO emerges as the optimal shield against alpha and proton irradiations. The equivalent neutron dose rate and removal cross-section values are obtained 49.8% and 0.142 for the composite with 20% RHEO, respectively. These findings, supported by computational simulations in this study, contribute valuable insights for the advancement of novel shielding materials crucial for future nuclear reactor technologies.
AtıfScopus24WoS22OpenAlex24İncele - DüzeltmeYalnız künye2024Scopus SJRQ1Retraction notice to “The influence of battery distance on a hybrid air-cooled cylindrical lithium-ion battery phase change material thermal management system for storing solar energy” [Journal of Energy Storage 52, Part B (2022) 104873] (Journal of Energy Storage (2022) 52(PB), (S2352152X22008805), (10.1016/j.est.2022.104873))
Akkurt, Nevzat; Aghakhani, S.; Mahmoud, Mustafa Z.; Tag El Din, ElSayed M.
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). Please note that an Expression of Concern has previously been published to alert readers to an ongoing investigation into this paper. This retraction supersedes the Expression of Concern. This article has been retracted at the request of the editor. In investigating concerns brought up regarding the authenticity of the article, the editor reached out to the authors for an explanation. Furthermore, the editor discovered suspicious changes in authorship between the original submission and the revised version of this paper. In summary, the author names Nevzat Akkurt, Mustafa Z. Mahmoud and ElSayed M. Tag El Din were added to the revised paper without explanation and without exceptional approval by the editor, which is contrary to the journal policy on changes to authorship. The authors failed to provide a satisfactory explanation to the above points. The editor therefore feels that the findings of the manuscript cannot be relied upon and that the article needs to be retracted.
- MakaleAçık Erişim2024Scopus SJRQ1Production of Ho2O3 and Dy2O3 rare earth oxides doped selenium thin film and investigation of surface morphology and optical properties
Aydin, Handan; Sait Kanca, M.; Kök, Mediha; Taşgin, Yahya; Tatar, Beyhan
Thin film technology aims to improve and develop the properties of materials by coating technology. In this study, thin films consisting of rare earth element and selenium semiconductor material, which have recently been preferred in technological applications due to their important properties, are examined. Selenium thin films doped with Ho2O3 and Dy2O3 rare earth oxides (REO) were fabricated on glass substrate by thermal evaporation method. The surface morphology and optical properties of the thin films were investigated. As a result of surface morphology examinations, it was determined that homogeneous thin films were obtained and the thickness of the thin films varied between 20 and 30 μm. In addition, the roughness value of the glass substrate decreased as a result of coating with doped selenium thin film. The band energy value obtained by UV-VIS measurements decreased compared to glass and was close to the selenium element value. In the comparison between selenium coatings doped with Ho2O3 and Dy2O3, a notable reduction in the Eg value was observed specifically in the Ho2O3 doped coatings.
AtıfScopus3OpenAlex3İncele - MakaleYalnız künye2024Scopus SJRQ1Influence of praseodymium oxide on the structural, mechanical and photon, charged particles, and neutron shielding properties of alumina borate glass
Acikgoz, Abuzer; Izguden, Ilyas; Tasgin, Yahya; Yilmaz, Demet; Demircan, Gokhan; Kalecik, Sedanur; Aktas, Bulent
The structural, mechanical and radiation shielding properties of (69-x)B2O3-20TeO2-10Al2O3-1HfO2-xPr6O11 (where x = 0, 0.25, 0.5, 0.75, 1 mol %) glass system were investigated. This study introduces a novel approach by incorporating Pr6O11 into glass composition, highlighting its unique contributions to enhancing elastic properties, fracture toughness, hardness, and radiation shielding abilities. Experimental measurements were conducted within the energy range of 59.54–661.62 keV and theoretical calculations are made for MAC values. The presence of Pr6O11 was noted to positively influence the gamma shielding capabilities. At 59.54 keV, the addition of 0.25 mol% Pr6O11 increased the mass attenuation coefficient of the glass by 2.9 %, and the addition of 1 mol% Pr6O11 increased it by 29.8 %. The addition of 0.25 mol% Pr6O11 increased the fast neutron removal cross section of the glass by 4.4 %. Also, it is observed that the glass with 1 mol% Pr6O11 is the best shielding material against alpha and proton particles. A significant enhancement of 24.36 % in the fracture toughness value was observed, increasing from 1.059 to 1.317 MPa m1/2 at 1 mol% Pr6O11. Experimental hardness values increased from 3.374 to 3.985 GPa, resulting in an improvement of 18.11 % at 1 mol% Pr6O11. The thermal stability (ΔT, °C) value demonstrated a notable increase from 85 to 106, indicating a significant 24.7 % improvement at 0.25 mol% Pr6O11.
AtıfScopus58WoS57OpenAlex60İncele - MakaleAçık Erişim2024Scopus SJRQ1A broad-spectrum biological activities of Heracleum humile extracts: A first report of the antiviral, anti-cancer and chemical properties
Ocal, Mustafa; Duran Yelken, Selda; Altunoglu, Yasemin Celik; Baloglu, Mehmet Cengiz; Soomro, Sanam Iram; Zengin, Gokhan; Angeloni, Simone; Mustafa, Ahmed M.; Caprioli, Giovanni; Paksoy, Mehmet Yavuz
The current work focused on researching the bioactive potential of ethyl acetate (EA), methanol (MeOH), and water extract of H. humile plant, specifically ethyl acetate, methanol extracts were acquired with maceration method, and water extract was obtained by the infusion method. The highest total phenolic ingredient was determined in the water extract, while the highest total flavonoid ingredient was found in the MeOH extract. The water extract displayed the most potent antioxidant activity in the assays used. The ethyl acetate extract showed the highest enzyme inhibition activity in Butyrylcholinesterase inhibition (BChE) and amylase assay. Antibacterial efficiency was analyzed using microdilution analysis. The minimum inhibitory concentration (MIC) amounts ranged from 125 to 500 μg/mL except for water extract. The antiviral potential of the extracts was assessed against Bovine herpes virus 1 (BoHV-1) (Cooper strain). Methanol extract showed more potent antiviral effect. Selectivity indices were calculated for ethyl acetate and methanol extract as 3.32 and 13.39, respectively. All extracts displayed Deoxyribonucleic Acid (DNA) protection activity at approximately 25%–35%. For cell viability evaluation, 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) test was performed against triple-negative human breast adenocarcinoma cells (MDA-MB-231) and Michigan Cancer Foundation-7 (MCF-7) cells. The most effective results were found in ethyl acetate extract at 48h. The 50% inhibitor concentrations (IC50) were determined for MDA-MB-231 and MCF-7 as 116.7 μg/mL and 247.9 μg/mL, respectively. Based on the bioactive compound content results, extracts of H. humile include valuable compounds that possess significant biological properties. In conclusion, these extracts could offer promising novel plant-derived therapeutics.
- MakaleAçık Erişim2024Scopus SJRQ1Experimental and theoretical results of gamma shielding features for copper based shape memory alloys
Niksarlıoğlu, Seçil; Akman, Ferdi; Agar, Osman; Kaçal, Mustafa Recep; Kanca, Muhammed Sait
In this study, the gamma ray attenuation characteristics for CuAlNi shape memory alloys with different proportions of Sn doping was investigated. We determined the mass attenuation coefficient (μ/ρ) of CuAlNiSn alloys both experimentally and theoretically within an energy range of 59.5–1332.5 keV. The experimental measurements were made using a high purity Germanium detector (HPGe) and theoretical calculations were made using WinXCOM program. To evaluate the gamma radiation shielding abilities of the alloy samples, the obtained (μ/ρ) values were used to determine the gamma protection parameters μ, HVL, TVL, MFP, and Zeff. In addition, the radiation protection efficiency (RPE) parameter was determined using gamma ray intensities in the absence and presence of the attenuator. Further analysis of the samples was conducted using a Rigaku Miniflex 600 model computer-controlled X-ray diffractometer (CuKα & λ = 1.5405 A0). The crystallographic structure of the alloys before and after irradiation was investigated. Other analysis which include EDX analysis (to investigate the chemical content) and SEM analysis (to investigate the microstructure) were conducted. According to result outcomes, gamma ray radiation did not affect the shape memory properties of structure. Another interesting observation is that, the radiation attenuation properties increase with increasing Sn concentration. Finally, we discovered that the CuAlNiSn4 alloy (which has the highest doping rate) provides good protection especially at low energy levels.
AtıfScopus5OpenAlex6İncele - MakaleYalnız künye2024Scopus SJRQ1Preparation and characterization of the highly efficient tetraphenylimidazole substituted Phthalocyanine/ZnO composite and investigation of its effect on the photocatalytic degradation of Rhodamine B and 2,4,6-trichlorophenol
Karaoğlu, Kaan; Yüzüak, Gizem Durak; Yüzüak, Ercüment; Turan, Hanife; Akçay, Hakkı Türker
Growing concerns about industrial waste-induced environmental degradation have driven research towards sustainable solutions. Photocatalytic degradation, fueled by light and avoiding harmful chemicals, offers a promising avenue due to its minimal environmental impact. ZnO, TiO₂, and their derivatives are particularly effective and widely studied photocatalysts. This study aims to prepare new composite materials bearing phthalocyanine and investigate the photocatalytic properties on the degradation of Rhodamine B dye and 2,4,6-trichlorophenol (TCP) as the model compounds. In the initial step, ZnO materials were synthesized using the solvothermal method. Subsequently, a novel Zn(II) complex, including peripherally tetra phenyl imidazole substituted phthalocyanine, was successfully prepared. The composite catalysts were prepared from ZnO materials produced with the tetraphenyl imidazole phthalocyanine Zn(II) complex, called TFI-Zn. The were characterized using instrumental techniques. The photocatalytic characteristics of the composite materials developed were further examined under varying quantities of catalyst and Rhodamine B, variable pH conditions, and varying intensities of UV-A light. In addition, the reusability of the catalyst was investigated. With the new composite photocatalyst prepared within the scope of this study, 98% degradation efficiency and 8.0 × 10−4 min−1 degradation rate was obtained on Rhodamine B solution in 40 min. The newly developed photocatalyst displayed remarkable catalytic activity that remained virtually unchanged for five consecutive cycles, indicating excellent reusability and operational stability. The photocatalytic degradation performance of ZnO-TFI-Zn (1) was also examined on TCP and 90% degradation activity was obtained at the end of 80 min.
AtıfScopus7WoS7OpenAlex7İncele - MakaleYalnız künye2024Scopus SJRQ1Resistance to magnesium sulphate attack of binary and ternary cementless self-compacting alkali-activated mortar
Şahin Yön, Merve; Karataş, Mehmet
The aim of this study is to investigate the effect of sulphate on self-compacting alkali-activated mortars (SCAAMs) produced using volcanic scoria (V), boron waste (B) and granulated blast furnace slag (G) together with alkali activators. Thus, the production of cement-free alkali-active mortar by recycling waste and reducing the CO2 effect increases the importance of this study. The fact that the waste material is provided free of charge and that V is readily available from nature provides economic advantages in the production of these mortars. In this experimental study, magnesium sulphate solution was utilized to define the sulphate resistance of SCAAMs. In binary SCAAMs, B was used with G in a ratio of NS:NH = 3.0, with an increase from 5 % to 15 %; in ternary mixtures, B was used together with G and V in the same proportions, in a ratio of NS:NH = 1.0. The tests involved immersion in 5 % magnesium sulphate solution for 1, 3 and 6 months. Mass development, compressive strength, visual inspection and microstructural changes were investigated. In general, the binary SCAAMs performed better in magnesium sulphate solution than the ternary SCAAMs, except in the 6th month. Considering the samples with the highest B content, a 100 % loss of compressive strength occurred in the B15G85 sample under the influence of sulphate for 6 months, while a loss of compressive strength of about 15 % occurred in the B15G40V45 sample. The results showed that the increase in B content caused a severe deterioration of the sulphate effect in the samples over time and that the V additive had a positive effect on the sulphate resistance.
AtıfScopus26WoS23OpenAlex19İncele - MakaleAçık Erişim2024Scopus SJRQ1Fabrication 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
Güler, Seval Hale; Güler, Ömer; Kavaz, E.; ALMisned, Ghada; Albayrak, M. Gökhan; 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 reinforced 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.
AtıfScopus22OpenAlex25İncele - MakaleYalnız künye2024Scopus SJRQ1Effect of oxidation on radiation shielding capacity of ZrNbTaMoW Refractory High Entropy Alloys (RHEA) for nuclear reactor applications: Experimental and theoretical assessment
Sakar, E.; Guler, O.; Alim, B.; Guler, S.H.; Dikici, B.; Lampke, T.
This study presents the production and comprehensive assessment of a Refractory High Entropy Alloy (RHEA) with a ZrNbTaMoW composition for possible usage nuclear reactor applications. The alloy was synthesized using the mechanical alloying (MA) method, and its radiation properties were examined. Elemental powders of Zr, Nb, Ta, Mo, and W were utilized in equimolar quantities during the 120-hour MA process, conducted under a high-purity Ar atmosphere to prevent oxidation. The obtained HEA was then subjected to a mechano-thermal process to transform it into Refractory High-Entropy Oxide (RHEO) for comparing their radiation-shielding performance under oxide conditions. The characterization of the produced alloys through X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron dispersive spectroscopy (EDS). The photon shielding parameters of the alloys were experimentally obtained for various energies emitted from a 133Ba radioactive source, employing a Canberra UltraLEGe semiconductor detector. Furthermore, theoretical calculations were performed to validate the experimental data and to evaluate the alloys' photon shielding capabilities comprehensively. For this purpose, Phy-X/PSD software was employed to determine mass attenuation coefficients, half-value layer, effective atomic number, and effective electron density. Fast neutron absorption capabilities were determined through the calculation of average absorption cross-sections in the 2–12 MeV energy range. The results showed that the oxidation process significantly diminished the photon absorption capacity of RHEA.
AtıfScopus34OpenAlex37İncele - MakaleYalnız künye2024Scopus SJRQ1A stratified Bayesian decision-making model for occupational risk assessment of production facilities
Gul, Muhammet; Yucesan, Melih; Karci, Coskun
In the production industry, harmony and good management of the workplace environment, production machinery/vehicles, and workers are necessary to carry out production by occupational health and safety (OHS) principles. Therefore, occupational risk assessment (ORA) is crucial for manufacturing-based industries. When deciding on the prioritization of risks in ORA, adding to the analysis “how the parameters defining the risk changes in possible different states in the future” positively affects the soundness of decision-making. Therefore, this study aims to develop a unique ORA model handling future changes in the importance levels of risk parameters in the risk assessment process. To this aim, the concept of stratification and the best-worst method (BWM) are used together to determine the importance weights of the risk parameters in the ORA. In addition, the Bayesian version of BWM considers more than one expert's evaluations without losing information. In a nutshell, an approach called stratified Bayesian BWM (SBBWM) that can be used for further studies has been introduced to the literature. The technique determines the priority scores of each hazard by technique for order preference by similarity to the ideal solution sorting (TOPSIS-Sort) method. Thus, while determining each hazard's priority score and order, the class of this risk has also been determined. The proposed approach evaluated thirty-six risks encountered in manufacturing, storage, handling, and laboratory processes of a flour production facility. Control measures to be taken for each risk were also determined. Methodologically, various scenario analyses and sensitivity studies were conducted to reveal how the results changed in different conditions. The proposed approach provides a more comprehensive procedure for production facilities than traditional methods and avoids the deficiencies of traditional methods.
AtıfScopus18WoS16OpenAlex18İncele - MakaleYalnız künye2024Scopus SJRQ1A closer-look on W and Pb alloys: In-depth evaluation in elastic modulus, gamma-ray, and neutron attenuation for critical applications
ALMisned, Ghada; Susoy, Gulfem; Sen Baykal, Duygu; Alkarrani, Hessa; Güler, Ömer; 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.
AtıfScopus28OpenAlex31İncele - MakaleAçık Erişim2024Scopus SJRQ1Determination of oxidative stress responses caused by aluminum oxide (γ-Al2O3 and α-Al2O3) nanoparticles in Gammarus pulex
Serdar, Osman; Aydin, Ayşe Nur; Çimen, Isıl Canan Çiçek
The rapid growth in the use of aluminum oxide nanoparticles (Al2O3 NPs) in various fields such as medicine, pharmacy, cosmetics industries and engineering, and the fact that these NPs and their wastes mix with the aquatic environment and damage the aquatic ecosystem, affect the organisms in the water, enter the food chain and reach humans is a major problem is cause for concern. The aim of this study is to investigate the oxidative stress caused by two separate forms of aluminum oxide, γ-Al2O3 and α-Al2O3, in Gammarus pulex, which is a good indicator species, with biochemical parameters. For this purpose, G. pulex was exposed to different concentrations (0, 10, 20, 40 ppm) of γ-Al2O3 and α-Al2O3 separately. The experiments were carried out for 24 and 96 h by creating 3 repeated experimental groups consisting of 4 groups. For biomarker analysis, superoxide dismutase (SOD), catalase (CAT) activities and glutathione (GSH) and thiobarbituric acid (TBARS) levels were performed using an ELISA kit. As a result of the in experimental study, it was observed that both nanoparticles affected oxidative stress and antioxidant parameters after 96 h compared to the control group. Increases in SOD activity were observed, γ-Al2O3 caused a decrease in CAT activity at 24 h, and α- Al2O3 caused increases in CAT activity at 96 h. Decreases in GSH levels and increases in TBARS levels have been observed.
AtıfScopus14OpenAlex14İncele - MakaleAçık Erişim2024Scopus SJRQ1Assessment of toxicity and oxidative stress induced by rare earth oxide nanoparticles in brine shrimp (Artemia salina)
Unal, Ilkay; Erturk Gurkan, Selin; Aydogdu, Burcu
This study meticulously explored the oxidative stress effects induced by lanthanum (III) oxide (La2O3), erbium (III) oxide (Er2O3), and yttrium (III) oxide (Y2O3) nanoparticles on Artemia salina, with the objective of evaluating the environmental toxicity of rare earth oxide nanoparticles. The characterization of the nanoparticles was conducted using a suite of advanced techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential analysis. Artemia salina, a widely recognized model organism in ecotoxicological research, was exposed to these nanoparticles under meticulously controlled laboratory conditions. The investigation focused on quantifying oxidative stress markers, such as reduced glutathione (GSH), malondialdehyde (MDA), and antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione-S-transferase (GST). The findings revealed significant alterations in these biomarkers, indicating nanoparticle-induced oxidative stress, which varied according to the type of nanoparticle and the duration of exposure.
AtıfScopus9OpenAlex9İncele