Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleAçık Erişim2026Scopus SJRQ1
    Large-eddy simulation of flow over a square prism with moving belts

    You, Rui; Fırat, Erhan

    This three-dimensional (3D) numerical study investigates the feasibility of controlling the intermittently reattaching flow (IRF) by using the moving-surface boundary-layer control (MSBC) method. To this end, a fixed square prism was preferred due to its geometric simplicity and was equipped with moving belts that placed side surfaces close to the trailing edges. The effects of three dimensionless key parameters including velocity ratio (i.e., VR, the ratio of the velocity of the moving belt to the freestream velocity), length ratio (i.e., LR, the ratio of the belt length to the edge length of the square prism), and gap ratio (i.e., GR, the ratio of the spanwise distance between the neighboring belts to the edge length of the square prism) mainly on the aerodynamic characteristics were investigated using large-eddy simulation (LES). The findings suggest that the rise in VR and LR parameters leads to a proportional decrease in the time-averaged drag, 〈CD〉, attributable to their contribution to the linear momentum transfer mechanism by the moving surfaces. This mechanism, firstly, provides an additional thrust to the prism in the opposite direction of the main flow. Secondly, this mechanism increases the base pressure by stretching the shear layers from the leading edges of the prism in the streamwise direction. For LR = 0.4 and VR = 4, a 17 % reduction in 〈CD〉 was observed. Additionally, the root-mean-square (RMS) values of fluctuating drag and lift coefficients, CD-RMS and CL-RMS, have decreased by 71 % and 55 %, respectively. Conversely, the increase in the GR parameter led to an increase in the spanwise distance between each individual moving belt and a reduction in the positive effect of the linear momentum transfer mechanism on the 〈CD〉 reduction. The segmentation of moving belts along the spanwise direction also triggered the vorticity redistribution mechanism concurrently. The study also elucidated the underlying mechanisms that led to the failure of the vorticity redistribution mechanism to adequately reduce the 〈CD〉.

  • MakaleAçık Erişim2026Scopus SJRQ3
    Optimized bioleaching of spent FCC catalysts for the recovery of critical metals

    Erust, Ceren; Altındaş, Mediha Demet Okudan

    Spent fluid catalytic cracking (FCC) catalysts, generated in large volumes by petroleum refining, represent a promising secondary source of critical metals such as lanthanum, cerium, titanium, and vanadium. In this study, a biohydrometallurgical approach was applied to recover these metals using Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans. The spent FCC catalyst, supplied by petroleum refinery, was characterized through WD-XRF, XRD, SEM-EDS, and ICP-OES analyses, confirming significant concentrations of La2O3 (1.44%), TiO2 (1.43%), and CeO2 (0.23%). Bioleaching experiments were conducted under varying initial ferrous ion concentrations (1–9 g/L) and pulp densities (5–20% w/v) at 35°C over 14 days. Results revealed that the optimal conditions for maximum recovery occurred at 5 g/L Fe2+ and 10% pulp density, achieving leaching efficiencies of 95.5% for La, 90.5% for Ce, 92.5% for Ti, and 60.8% for V within seven days. Beyond this period, efficiency decreased due to jarosite formation and microbial activity constraints. The findings confirm that bioleaching is a cost-effective and sustainable route that aligns with circular economy principles by reducing reliance on virgin rare earth mining while mitigating the environmental impact of catalyst disposal.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleYayıncıda açık erişim2026Scopus SJRQ2
    Sperm cryopreservation of sex-reversed rainbow trout (Oncorhynchus mykiss): incorporation of amino acids and anti-oxidants to the extender media to improve the anti-oxidant system

    Kocabaş, Filiz Kutluyer; Kocabaş, Mehmet; Benzer, Fulya; Erişir, Mine

    Anti-oxidants are vital for protecting sperm and can mitigate the negative effects associated with cryopreservation. This study was conducted to evaluate the protective effects of adding anti-oxidants (vitamins and amino acids) to extender in sex-reversed rainbow trout (Oncorhynchus mykiss) sperm. The collected sperm was diluted at the ratio of 1: 5 by the extenders supplemented with different anti-oxidants including 1.00 mM of ascorbic acid and L-tryptophan, 2.00 mM of cysteine and α-tocopherol, and their combination. After dilution, the semen was aspirated into 0.50 mL straws, and the straws were placed on the tray, frozen for 10 min, and plunged into liquid nitrogen. Straws were thawed in a 30.00 ˚C water bath for 15 sec. The Sperm Class Analyzer System was used to evaluate sperm kinematics. The activity of anti-oxidant enzymes and lipid peroxidation were determined as oxidative stress indices. Our data indicated that the incorporation of anti-oxidants and amino acids increased sperm motility duration. The elevated activity of glutathione peroxidase, superoxide dismutase, and catalase in post-thaw samples indicates that the anti-oxidant system in sex-reversed rainbow trout sperm likely plays a crucial role in protecting membrane compounds from oxidation. In conclusion, the combination of 1.00 mM L-tryptophan and ascorbic acid to the extender media caused a prolonging effect in sperm motility after thawing and they have the potential to serve as effective agents for improving sperm cryosurvival.

  • MakaleYalnız künye2026Scopus SJRQ1
    Enhancing waiting time performance of clinical laboratories for pregnant patients with seasonal respiratory diseases: a simulation-based Lean Six Sigma approach

    Ortíz-Barrios, Miguel; Celani de Souza, Helder Jose; Petrillo, Antonella; Gul, Muhammet; Yücesan, Melih; Navarro-Jiménez, Eduardo; Alfaro-Saíz, Juan-José; Ariza-Ortíz, Andrés

    Purpose – Clinical laboratory performance is critical in managing seasonal respiratory diseases (SRDs); however, prolonged waiting times can lead to patient dissatisfaction and nonquality costs. This challenge is particularly acute for pregnant patients, who face increased health risks from diagnostic delays. This study aims to improve waiting times before sample collection in clinical laboratories serving pregnant patients with SRDs by integrating Lean Six Sigma (LSS) and Discrete-Event Simulation (DES). Design/methodology/approach – The proposed framework was validated in a public clinical laboratory using the DMAIC (Define–Measure–Analyze–Improve–Control) methodology. DES was embedded within the Analyze and Improve phases to model patient flow and assess improvement scenarios before implementation. Findings – The integrated LSS–DES approach resulted in a significant reduction in waiting times. During SRD peak periods, waiting time before sample collection for pregnant patients decreased from 1.01 to 0.10 h per patient. These results demonstrate the framework's effectiveness and practical usefulness for decision-makers seeking performance improvements in resource-constrained healthcare environments. Originality/value – This study enhances existing literature by integrating LSS and DES to address laboratory performance challenges associated with SRDs. The combined LSS-DES used for pregnant patients during outbreak periods is novel. The study offers contextual innovation for a vulnerable population, methodological advancement through embedding DES within the DMAIC cycle, and practical laboratory validation. The framework is particularly valuable for low- and middle-income countries (LMICs), where scalable solutions are essential.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
  • MakaleAçık Erişim2026Scopus SJRQ1
    Change in phase stability and transformation kinetics of NiTiCuW alloy after heat treatment at 650–850 °C

    Tatar, Cengiz; Kök, Mediha; Kanca, M. Sait

    In this study, the effects of different heat treatment temperatures (650 °C, 750 °C, and 850 °C) on the phase transformation behavior, microstructure, thermodynamic parameters, and microhardness of the NiTiCuW alloy, produced by adding tungsten (W) to the NiTiCu shape memory alloy, were investigated. The crystal structure change was determined by X-ray diffraction (XRD), the transformation temperatures were determined by differential scanning calorimetry (DSC), the microstructure was examined by scanning electron microscopy (SEM), and the mechanical properties were evaluated by Vickers microhardness measurements. XRD results showed that the reference and 850 °C samples were predominantly in the B2 (austenite) phase at room temperature, while martensitic phases (B19/B19′) became prominent at 650 °C and 750 °C. DSC analyses revealed that the transformation peaks became sharper at 650 °C and the R-phase transformation could be observed; at 750 °C, the peaks broadened, indicating a decrease in transformation stability. The austenite finish temperature (Af) increased from 2.1 °C (reference) to 52.9 °C at 650 °C and 60.3 °C at 750 °C, while it remained low (4.5 °C) at 850 °C. Thermodynamic evaluations showed that ΔS increased at 650 °C (0.053 J/g K) and decreased at 750–850 °C (≈0.032 J/g K). Microhardness reached its maximum value at 650 °C (398 Hv), decreased at 750 °C (271 Hv), and showed an upward trend again at 850 °C (351 Hv), compared to the reference value (243 Hv). These results indicate that the heat treatment temperature critically determines the functional and mechanical performance of the NiTiCuW alloy.

  • MakaleAçık Erişim2026Scopus SJRQ2
    Occurrence of Antimicrobial Resistance in Kocuria rhizophila Bacteria Isolated From Salmo munzuricus (Teleostei: Salmonidae) Samples in Natural Resources

    Kar, Bülent

    Global warming and environmental pollution trigger the emergence of antimicrobial-resistant (AMR) opportunistic pathogens in the aquatic microflora. This study aimed to determine the characterization and AMR profile of the opportunistic pathogen Kocuria rhizophila isolated from the tissues of Salmo munzuricus (Munzur trout), an endemic species. Samples collected from the Munzur River were identified using morphological and molecular (16S rDNA) methods; bacterial isolates were characterized by MALDI-TOF and sequencing. The resistance status against 11 different antibiotics was analyzed with the Kirby-Bauer method. The findings revealed that the isolates (with 99.51% accuracy as K. rhizophila) showed full resistance to Penicillin G (p < 0.01) and were moderately sensitive to gentamicin and tetracycline. High sensitivity to amoxicillin and ampicillin was detected. These findings demonstrate that even in natural environments, the fish microbiome in wild endemic populations can be susceptible to the development of AMR in response to environmental changes. Therefore, determining the resistance of opportunistic pathogens in wild fish species such as Salmo munzuricus to different classes of antibiotics and studying their spread is extremely important for natural ecosystems.

  • MakaleYalnız künye2026Scopus SJRQ2
    Depositional settings and basin-fill evolution of the restricted platform system on the Intra Pontide belt during the Late Eocene-?Early Oligocene transition, western black sea region, Turkey

    Us, Muhammed Sami; Tekin, Erdoğan; Akgün, Funda; Kayseri-Özer, Mine Sezgül; Varol, Baki Erdoğan

    This study presents an integrated sedimentological, microfacies, and palynological analyses of the Late Eocene–?Early Oligocene (Priabonian–?Rupelian) Akçapınar Formation, exposed along the Soğanlı Stream in the Intra-Pontide Belt of the Western Black Sea region, Turkey. The formation, which overlies the evaporitic Pürçükören Formation and locally the Soğanlı Formation, records deposition in restricted shallow-marine to a lagoonal setting during a phase of significant tectonic and climatic reorganization. Detailed field mapping and measured stratigraphic sections, supported by petrographic, XRD, and SEM analyses, reveal mud-supported textures, limited faunal diversity, and thin-shelled gastropods, consistent with low-energy, brackish conditions. Palynological assemblages, identified here for the first time, refine the age constraints and document freshwater influence, whereas mineralogical data indicate alternating arid (smectite-rich) and humid (chlorite–illite-rich) intervals. Microfacies patterns (Mf1–Mf4) and lithofacies associations (Lf1–Lf8) were synthesized into three-dimensional depositional models, illustrating progressive basin restriction, episodic subaerial exposure, and evaporite precipitation. The multi-proxy approach, integrating sedimentology, microfacies, palynology, and mineralogy, refined the depositional model of the Akçapınar Formation, revealing facies heterogeneity driven by the interplay of tectonically induced basin isolation, relative sea-level fluctuations, and paleoclimatic oscillations during the Eocene–Oligocene transition, and providing new insights into the paleogeographic evolution of the northern Neo-Tethys during the final stages of its closure.

  • MakaleAçık Erişim2026Scopus SJRQ1
    Sustainable material pathways: Utilizing biomass-derived bio-oils from agricultural wastes to restore aged asphalt binder properties

    Yalcin, Beyza Furtana; Yilmaz, Mehmet; Yalcin, Erkut; Kok, Baha Vural

    This study explores the valorization of agricultural biomass wastes into high-value bio-based materials by evaluating the performance of pyrolysis-derived bio-oils obtained from straw, pine cone, and olive pomace for the rejuvenation of aged asphalt binders. The effectiveness of these biomass-derived bio-oils was comparatively assessed against two commercial rejuvenators to enhance binder reusability using renewable resources. The optimum rejuvenator dosages were determined through penetration, viscosity, and dynamic shear rheometer (DSR) tests, while the associated physical and chemical modifications were investigated using FTIR, SEM-EDS, and elemental analyses. Penetration and viscosity results indicated that all rejuvenators significantly reduced binder stiffness and improved fluidity. DSR analysis indicated that increasing rejuvenator content reduced G∗/sin δ values, reflecting a decrease in binder stiffness and a softening effect of the rejuvenators, which contributes to restoring the viscoelastic balance of the aged binder. FTIR results demonstrated that biomass-derived bio-oils, particularly those from pine cone and straw, effectively reduced carbonyl (C=O) and sulfoxide (S=O) functional groups, indicating strong chemical rejuvenation. SEM-EDS analyses showed that the heterogeneous and porous morphology of bio-oils promoted improved interaction with the asphalt binder. Based on the combined results of the three experimental approaches, the optimum rejuvenator dosages were identified as 25% for commercial products, 35% for pine cone and olive pomace bio-oils, and 45% for straw bio-oil. Overall, the findings highlight that biomass-derived bio-oils produced via pyrolysis offer a sustainable and performance-effective pathway for converting agricultural residues into value-added materials, supporting circular bioenergy and biomass utilization strategies.

    • SDG 2 · Açlığa Son
    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 12 · Sorumlu Üretim ve Tüketim
    • SDG 13 · İklim Eylemi
    AtıfScopus2WoS3OpenAlex3
    ScopusWeb of Scienceİncele
  • MakaleYayıncıda açık erişim2026Scopus SJRQ1
    tVNS Mitigates Neuroinflammation and Nociception in a Rodent LPS Endotoxemia Model

    Atalar, Kerem; Alim, Ece; Calikusu, Aysen; Abbasoglu Topa, Elif Gulcicek; Gok Dagidir, Hale; Bahcelioglu, Meltem; Bukan, Neslihan; Erten, Fusun; Sahin, Kazım; Akarca Dizakar, Saadet Özen

    The vagus nerve plays a modulatory role in the gut-brain axis. Intestinal barrier dysfunction and lipopolysaccharide (LPS) leakage into the systemic circulation are associated with several conditions, such as irritable bowel syndrome (IBS) and migraine headache. This study investigates the impact of non-invasive transauricular vagus nerve stimulation (tVNS) on the neuroinflammatory markers and pain behavior following an acute LPS challenge. Sprague–Dawley rats (n = 28) were given LPS or vehicle and subjected to tVNS or sham intervention in an acute LPS animal model that mimics the systemic consequences of barrier dysfunction. Behaviors were evaluated at the baseline and 6 h later, complemented by testing the levels of serum and brain neuroinflammatory markers. Behavioral analyses revealed that LPS exposure reduced the time spent in the open arm, grooming duration, and periorbital mechanical pain thresholds, and increased freezing duration. The tVNS intervention reversed these behavioral changes induced by LPS. LPS administration triggered elevated serum levels of IL-6, CGRP, haptoglobin, and VE-cadherin. LPS also increased IL-1β, PAR-2, haptoglobin, CGRP, and HMGB1 levels in the brain tissue. The tVNS intervention reversed the effects observed in the brain, but it did not change the elevated levels of inflammatory molecules in the systemic circulation. tVNS has the potential to modulate neuroimmune interactions, with an early impact on the brain during LPS surge. tVNS may have potential therapeutic benefits in managing pain-related disorders associated with LPS endotoxemia.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
  • MakaleAçık Erişim2026Scopus SJRQ1
    Surface EMG-Based Hand Gesture Recognition Using a Hybrid Multistream Deep Learning Architecture

    Çelik, Yusuf; Can, Umit

    Surface electromyography (sEMG) enables non-invasive measurement of muscle activity for applications such as human–machine interaction, rehabilitation, and prosthesis control. However, high noise levels, inter-subject variability, and the complex nature of muscle activation hinder robust gesture classification. This study proposes a multistream hybrid deep-learning architecture for the FORS-EMG dataset to address these challenges. The model integrates Temporal Convolutional Networks (TCN), depthwise separable convolutions, bidirectional Long Short-Term Memory (LSTM)–Gated Recurrent Unit (GRU) layers, and a Transformer encoder to capture complementary temporal and spectral patterns, and an ArcFace-based classifier to enhance class separability. We evaluate the approach under three protocols: subject-wise, random split without augmentation, and random split with augmentation. In the augmented random-split setting, the model attains 96.4% accuracy, surpassing previously reported values. In the subject-wise setting, accuracy is 74%, revealing limited cross-user generalization. The results demonstrate the method’s high performance and highlight the impact of data-partition strategies for real-world sEMG-based gesture recognition.

    AtıfScopus4WoS4OpenAlex7
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2026Scopus SJRQ1
    Impact of soft-storey irregularity on the seismic safety of reinforced concrete buildings

    Tektaş, Şeyhmus; Tam, Gürkan; Yön, Burak

    This study evaluates the effect of soft-storey irregularity on the seismic fragility of reinforced concrete buildings by comparing fragility curves based on inter-storey drift and element damage. This comparison highlights the novelty of the study. For numerical analyses, a typical four-storey reinforced concrete building with a ground storey of 4.5 m and typical storeys of 3 m, having a current storey plan, was modeled as both a regular and soft-storey building. To model nonlinear behavior, the assumption of lumped plastic hinges at the ends of the structural elements was made. Static pushover analyses of the building models created in SeismoStruct 2022 were performed until the roof displacement reached 3% of the building height, while nonlinear incremental dynamic analyses were carried out using 11 real ground motion records obtained from AFAD. The records were scaled between 0.1 g and 1.0 g and applied in the x- and y-directions for both buildings, yielding a total of 440 dynamic analyses. Static pushover analyses generated capacity curves for both regular and soft-storey buildings. Incremental dynamic analyses revealed maximum responses, inter-storey drifts, damage distributions, and fragility curves for both regular and soft-storey buildings. Fragility curves were obtained using both HAZUS inter-storey drift limit values and TBEC 2018 section-based strain limits. The results showed that fragility curves generated based on inter-storey drifts yielded more sensitive results than those generated based on damage at the critical storey. Furthermore, it was determined that for an earthquake acceleration of 0.5 g, the probability of a soft-storey building collapsing was 30% higher than that of a regular building.

    • SDG 11 · Sürdürülebilir Şehirler ve Topluluklar
  • MakaleAçık Erişim2026Scopus SJRQ2
    Synergistic Effect of Cylindrical Fins and Phase Change Material on the Thermal and Economic Performance of a Double-Slope Solar Distillation Device Under Tunceli Climatic Conditions

    Tuğan, Volkan; Işık, Erdem; İnallı, Mustafa

    Global water scarcity driven by population growth, climate variability, and rising freshwater demand increases the need for more efficient solar desalination systems. In this study, a double-slope solar distillation device supported by a phase change material pool was developed to improve freshwater production. The phase change material layer was placed directly beneath the absorber plate to store excess thermal energy during peak solar radiation and release it during low-radiation periods. To strengthen thermal interaction between the absorber surface and the storage medium, cylindrical fins were embedded within the phase change material pool. The development of a double-slope solar distillation device integrated with a finned phase change material pool, and the simultaneous comparison of the thermal efficiency and economic analyses of single-slope and double-slope solar distillation devices under the same climatic conditions, are the prominent features of this study. Additionally, the performance of solar distillation devices has not previously been investigated under the climatic conditions of Tunceli, which further motivates this research. The developed system reached a peak freshwater productivity of 2459.2 g/m2/day, providing a 21.4% enhancement over the conventional configuration. In addition, the thermal efficiency increased from 17.7% in the conventional unit to 21.4% in the phase change material-assisted design. The economic analysis showed that the cost of distilled water was $0.097/kg for the conventional system and $0.105/kg for the proposed system, with the corresponding payback periods being approximately 11 and 12 months, respectively.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    • SDG 12 · Sorumlu Üretim ve Tüketim
    • SDG 13 · İklim Eylemi
    AtıfScopus2WoS2OpenAlex2
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2026Scopus SJRQ1
    Comprehensive Analysis of Phytochemical Compounds in Seeds of Indigenous Grape Varieties Cultivated in Southeastern Anatolia: Fatty Acids, Tocopherols, Phytosterols, Vitamins, and Antioxidant Properties

    Odabaşioğlu, Mehmet İlhan; Çakır, Atilla; Karaca Sanyürek, Nesrin; İşlek, Fırat

    Aim: In this study, the phytochemical composition of the seeds of twelve different local grape (Vitis vinifera L.) varieties traditionally cultivated in the Southeastern Anatolia Region (Diyarbakır, Türkiye) was investigated using a holistic approach. The main objective of the study was to evaluate the associations of the effects of berry skin colour, the ripening stage and utilization type on the fatty acid profile, tocopherol and phytosterol contents, vitamin K and D levels, antioxidant capacity (DPPH) and lipid peroxidation (MDA) of grape seeds. Method: The seeds of grape varieties belonging to four different colour groups, grown on their own roots, were harvested during the 2017 growing season and analysed. Fatty acid composition was determined by gas chromatography (GC), vitamin and phytosterol contents by HPLC-UV, MDA content by the thiobarbituric acid reactive substance (TBARS) method, and antioxidant capacity by the DPPH radical scavenging assay. Findings: Linoleic acid was identified as the predominant fatty acid in all varieties (53.68–67.06%), followed by oleic acid (13.80–27.32%). α-Tocopherol was identified as the predominant tocopherol form (1.597–4.703 mg kg−1), whilst β-sitosterol was the phytosterol component present at the highest level (915.67–3340.42 µg g−1). Statistically significant varietal differences were detected for most measured phytochemical parameters. Group-wise differences associated with berry skin colour and ripening stage were observed for selected traits. Overall, varietal differences appeared to be more pronounced than those associated with berry skin colour or ripening stage. It was observed that the differences in phytochemical composition between the various commercial classifications of grapes were very limited. Result: The findings reveal that the seeds of the local grape varieties studied exhibit a rich phytochemical profile and represent an important source of bioactive compounds that could be utilised, particularly in the functional food, nutraceutical and cosmetics industries. The ‘Tahannebi’ variety stood out as the one with the highest values across many parameters. Differences observed among samples of the same cultivar collected from different vineyards suggest that vineyard-specific conditions may contribute to variation in selected phytochemical traits. Future multi-year and multi-location studies are needed to confirm the stability of these phytochemical profiles and to further clarify genotype × environment interactions.

    • SDG 2 · Açlığa Son
  • MakaleYalnız künye2026Scopus SJRQ3
    Characteristics of the growth rate, fatty acid profile, and shell content of the freshwater snail Viviparus contectus (Millet, 1813)

    Kocabaş, Filiz Kutluyer; Kizak, Volkan; Özçiçek, Esin; Kocabaş, Mehmet; Yilmaz, Ökkeş

    Freshwater snails are a nutritious food source, providing vital amino acids, minerals, and protein with low lipid levels. Hence, the adaptation ability, growth rate, fatty acid (FA) profile, and shell content of Viviparus contectus were determined. Biometric measurements were recorded for 6 months. Over the 6-month cultivation period, specific growth rates were recorded as 0.32% · day-1 for shell length and 0.92% · day-1 for body weight. The FA profile of the freshwater snail included a total of 32 compounds with saturated, monounsaturated, and polyunsaturated FAs represented by 13, 10, and 9 types, respectively. Monounsaturated fatty acids (MUFAs) exhibited the highest concentration, followed by saturated fatty acids (SFAs) s at 35.14% and polyunsaturated fatty acids (PUFAs) at 14.57%. Stearic acid (C18:0), erucic acid (C22:1 n-9), and arachidonic acid (C20:4 n-6) were determined as the most abundant FAs within the saturated, monounsaturated, and polyunsaturated FAs classes, respectively. The energy-dispersive X-ray spectroscopy spectra analysis revealed that the shell powder composition consisted of the elements, such as carbon, oxygen, calcium, iron, manganese, and silicium. Overall, V. contectus showed a clear increase in growth over the cultivation period, and future studies are needed to obtain the best culture conditions and intensive production of the species.

    • SDG 2 · Açlığa Son
    • SDG 14 · Sudaki Yaşam
  • MakaleAçık Erişim2026Scopus SJRQ4
    Solvent Extraction of Copper from Sulfate Solutions Using Acorga OPT5510; [Extracción de cobre de soluciones de sulfato mediante solventes con Acorga OPT5510]

    Karacahan, Mehmet Kayra

    This study used a solvent extraction technique with AcorgaOPT5510 extractant in kerosene to examine the extraction of copper ions from the actual leach solution produced after leaching malachite ore in sulfuric acid solutions. On the Cu/Fe separation factor and the effectiveness of copper extraction, the impacts of significant parameters, including stirring speed, contact duration, extractant concentration, beginning solution pH, and temperature, were examined. The following values were chosen as the optimal ones: 1:1, 1.5, 12%, 20 °C, 10 min, 10 min, and 500 rpm for maximum Cu2+ extraction from the aqueous-phase, aqueous/organic phase ratio, equilibrium pH of the aqueous phase, extractant concentration, temperature, contact time, settling time, and stirring speed. Under these conditions, 94% of the copper in the leach solution was removed, yielding about 40.09 Cu/Fe separation factor. A McCabe-Thiele plot was revealed, and it was shown that a two-step extraction procedure would yield the best results. Furthermore, employing a sulfuric acid concentration of 4 mol·L-1 for 10 minutes, the loaded organic phase was stripped and recovered 91% copper.

    • SDG 12 · Sorumlu Üretim ve Tüketim
  • MakaleAçık Erişim2026Scopus SJRQ2
    Enhanced Radiation Shielding and Structural Modifications in Samarium (III) Oxide-Reinforced Type 316L Stainless Steel Composites for Nuclear Applications: A Comprehensive Evaluation of Physical, Structural, Mechanical, Gamma-Ray, and Neutron Attenuation Properties

    Yayla, Nihal; Albayrak, M. Gökhan; Güler, Ömer; Sen Baykal, Duygu; Alkarrani, Hessa; ALMisned, Ghada; Tekin, H.O.

    Type 316L stainless steel (316L-SS) is widely recognized for its exceptional corrosion resistance, making it a preferred material in various industries. However, conventional stainless steel materials are inadequate for radiation shielding applications. While oxide dispersion-strengthened alloy composites with a 316L-SS matrix have been extensively studied in the literature for their mechanical creep properties, their radiation shielding capabilities remain insufficiently explored. This study investigates the potential of samarium oxide (Sm2O3) doped to improve the structural, physical, mechanical, and radiation shielding properties of 316L-SS composites. Samples containing 1%, 5%, 10%, and 20% Sm2O3 by weight were synthesized and extensively characterized using X-ray diffraction and scanning electron microscopy. These analyses revealed enhanced homogeneity and refined grain structure with increasing Sm2O3 content. Gamma-ray and neutron shielding properties demonstrated significant improvements, particularly in composites with 20% Sm2O3 reinforcement, as evidenced by lower half-value layer and mean free path values, along with an increased fast neutron removal cross section. However, a trade-off was observed between radiation shielding performance and mechanical properties: As the Sm2O3 content increased, the elastic modulus decreased, indicating reduced stiffness due to the incorporation of Sm2O3. This trade-off suggests that while Sm2O3 reinforcement effectively enhances radiation shielding, it may not be ideal for structural applications requiring high mechanical strength. Nevertheless, these findings highlight the potential of Sm2O3-doped 316L-SS composites for nonstructural radiation protection systems, particularly in applications where improved shielding performance is prioritized over mechanical stiffness.

    AtıfScopus5OpenAlex7
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2026Scopus SJRQ4
    CLASSIFYING VOLUNTEERS PARTICIPATED IN SEARCH AND RESCUE ACTIVITIES: A COMPARATIVE ANALYSIS OF TOPSIS-SORT AND ORESTE-SORT METHODS

    Ozdemir, Umit; Mete, Suleyman; Gul, Muhammet

    Volunteers collaborate with professionals to provide institutional assistance in various areas; their management differs from that of professionals. To maximise volunteer productivity, categorising volunteers according to their knowledge and experience levels and distributing tasks increases volunteer retention and task efficiency. This study categorizes volunteers into four groups, fulfilling nine criteria identified through a literature review of search and rescue activities. TOPSIS-Sort and ORESTE-Sort (Optimist and Pessimist approaches) are employed in classification. Only one alternative is consistently assigned to the same class across all methods. While ORESTE-Sort offers greater flexibility and three distinct classification outcomes, it is more complex and sensitive to threshold values. TOPSIS-Sort, though simpler and producing a single classification, requires criterion weight. The Wilcoxon signed rank test is applied to evaluate the similarity between ORESTE-Sort and TOPSIS-Sort results; there are significant differences between the two methods. The study concludes by comparing the methods' applications, steps, and solution approaches, highlighting their respective advantages and disadvantages, and suggesting directions for future research.

  • MakaleYalnız künye2026Scopus SJRQ2
    Influence of Low-SiC Content on the Tribological and Electrical Properties of Cu Composites Produced by Spark Plasma Sintering

    Çelik, Ertuğrul

    In this study, copper matrix composites reinforced with varying silicon carbide (SiC) contents (0.25, 0.5, 0.75, and 1 wt.%) were fabricated using spark plasma sintering (SPS). The effects of SiC reinforcement on the microstructure, hardness, porosity, electrical conductivity, and tribological performance were systematically investigated. Brinell hardness values increased with higher SiC content, reaching up to 76 HB for the 1 wt.% SiC composite. This improvement was accompanied by a gradual increase in porosity from 0.6 to 2.1%. Electrical conductivity decreased from 93% IACS to 66% IACS with increasing SiC content. Tribological tests revealed that the specific wear rate was significantly reduced, reaching as low as 1.1 × 10−4 mm3/N m at 15 N due to the formation of a protective tribolayer. These results demonstrate that incorporating small amounts of SiC can substantially improve hardness and wear resistance, while maintaining acceptable electrical performance, making Cu-SiC composites promising candidates for durable electrical contact applications.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus1WoS1OpenAlex1
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2026Scopus SJRQ1
    Effect of Ni–Co–Cr additions on the microstructural and magnetic field–induced radiation shielding behavior of Fe–Si–B alloys

    Taşgın, Yahya; Taşar, Fatih

    Fe–Si–B–based amorphous metallic glasses were synthesized via powder metallurgy and arc melting, followed by alloying with 10 wt% Ni, Co, or Cr. The alloys were examined in both as-cast and heat-treated conditions to assess the combined influence of composition, thermal relaxation, and magnetic processing on their mechanical and radiation-shielding properties. Microstructural characterizations (XRD, SEM, EDS) confirmed homogeneous alloying and the presence of Fe2B, Fe0.91Si0.09, and Ni/Co/Cr-boride phases. After alloying and heat treatment, the average Vickers hardness increased from 313 HV (base Fe-Si-B) to 480 HV. All synthesized samples were exposed to a 1 T magnetic field, and their gamma-ray attenuation behavior was subsequently evaluated using a Ba-133 source (80.99–383.85 keV). After magnetic exposure, the linear attenuation coefficient (LAC) increased by ≈ 3–4% for Co-doped alloys, ≈ 2% for Ni-doped and base Fe–Si–B alloys, and < 0.5% for Cr-doped alloys, accompanied by a corresponding reduction in half-value layer (HVL) from 1.86 cm to 1.79 cm. The fast-neutron removal cross-section (ΣR) also exhibited a modest rise (≈2%). These enhancements are attributed to field-induced microstructural relaxation, including domain alignment, internal-stress reduction, and partial free-volume collapse, which subtly modify the local electron-density distribution without altering the bulk composition. Overall, the findings demonstrate that Ni–Co–Cr alloying, combined with controlled magnetic-field exposure, offers an effective and non-destructive route to enhance both the mechanical durability and γ-ray/fast-neutron shielding performance of Fe-based amorphous alloys, highlighting their potential for magnetically tunable protective coatings and advanced smart-shielding applications. In some applications, both the magnetic properties and radiation shielding properties of the material used are important. This study investigates the effects of Ni, Co, and Cr on the magnetic properties of the Fe-Si-B alloy, while also demonstrating changes in radiation shielding properties.

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    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2026Scopus SJRQ3
    Bioactive compounds in mucus and shell microstructure of the European ear snail (Radix auricularia)

    Kocabaş, Kutluyer; Kocabaş, M.; Kizak, V.; Korkmaz, B.

    Radix auricularia is a non-native and invasive freshwater snail species and it may have destructive impacts on biodiversity and ecosystem structure. In recent years, snail mucus, as a sticky substance, has garnered significant attention in the medical and cosmetic industries due to its content of numerous bioactive compounds. Despite frequently being discarded as waste due to the build-up of calcium carbonate crystals through biomineralization, shells of freshwater snail serve multiple functions in aquatic environments and have potential industrial applications. Hence, this study aims to identify bioactive compounds in the mucus and analyze the shell microstructure and mineralogy of the European ear snail (Radix auricularia). Bioactive constituents of mucus were characterized by Gas Chromatography-Mass Spectrometry (GC-FID-MS) analysis. We also conducted analyses on the organic matrix of shells from R. auricularia using X-ray diffraction (XRD) and Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS). Our results indicated that ten compounds are characterized by Eicosane (34.16%), 9-Octadecen-1-ol, (Z)-(11.86%) and N,N-Dimetylpalmitamide (5.55%) as the main components of mucus. The antioxidant potential, antifungal and anti-inflammatory properties of Eicosane was in notable quantity in the mucus. In addition, the elemental composition of shell powder comprised of carbon, aluminium, oxygen, calcium, iron, magnesium, silicium, manganese, sodium, sulphur and phosphorus. Aragonite emerged as the dominant mineralogy in the inorganic layer of their shells, as confirmed by XRD. Overall, individual compounds of mucus could be isolated and purified mucus compounds could have applications in pharmaceuticals and health sectors. The shells of R. auricularia offer potential for diverse applications and contribute to environmental sustainability as valuable biomaterials.