Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(102)
- Güler, Ömer(69)
- Akkurt, Nevzat(68)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(49)
- Celik, Erkan(45)
- Zengin, Gokhan(40)
- Serdar, Osman(39)
- Kocabaş, Mehmet(37)
- Aslan, Naim(31)
- Baskonus, Haci Mehmet(31)
- Bulut, Hasan(31)
- Mete, Suleyman(31)
- Paksoy, Mehmet Yavuz(30)
- Kök, Mediha(27)
- Ince, Muharrem(26)
- Yildirim, Ozal(26)
- Özkul, İskender(26)
- Sulaiman, Tukur Abdulkadir(25)
- Topal, Murat(25)
- Guler, Omer(24)
- Serin, Faruk(23)
- Benzer, Fulya(22)
- Erten, Fusun(22)
- Alataş, Mevlüt(21)
- Güler, Seval Hale(21)
- Baykal, Duygu Sen(20)
- Taşgın, Yahya(20)
- Kutlu, Banu(19)
- Onat, Onur(19)
- Sahin, Kazim(19)
- Tanyol, Mehtap(19)
- Torğut, Gülben(19)
- Yildirim, Numan(19)
- Kahraman, Gökhan(18)
- Orhan, Cemal(18)
- Say, Yakup(18)
- Susam, Selim Orhun(18)
- Utku, Anıl(18)
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ2Solvent extraction of rare earth elements and α-alumina production from pregnant leaching solution obtained from Turkish bauxite-related ore
Erust, Ceren; Uysal, Turan
The use of bauxite-related shales as a secondary source for the extraction of rare earth elements (REEs) is very important to meet the raw material supply, which is the keystone of advanced technology applications. This study presents the investigation into the recovery of REEs from Kızıldağ shale ore and the potential utilization of its leach residue as a silica source. Mineralogical analysis revealed that the ore predominantly consists of paragonite, muscovite, quartz, pyrophyllite, and calcite. Calcined ore was subjected to acid leaching, and the resulting pregnant solution was purified using solvent extraction to separate from aluminum the ∑REEs with a content of 1887.35 ppm. Optimal solvent extraction conditions 1.5 M D2EHPA, 50% O/A ratio, pH 1.5, and 15-minute mixing time achieved 95% total REE extraction, with efficiency in the order Pr > La > Nd > Ce > Dy > Y > Sc. To purify Al from the Fe- and K-rich solution post-SX, electrolysis was performed, resulting in 97.16% precipitation efficiency of Al as Al(OH)3 at pH 5. The precipitate was subsequently roasted at 1100°C to produce α-alumina with 75.2% Al2O3 content. These findings confirm the technical feasibility of recovering REEs and producing coarse-purity alumina from Kızıldağ shale ore.
AtıfScopus1WoS3OpenAlex1
İncele - MakaleYalnız künye2026Scopus SJRQ2Oxide Dispersion, Microstructure, and Functional Evolution in La2O3 Modified Cu-Al-Mn-Fe Shape Memory Alloys
Karaduman, Oktay; Doğan, Fatih; Dehghanpour, Heydar; Yüzüak, Gizem Durak; Yüzüak, Ercüment; Canbay, Canan Aksu
Cu-Al-Mn-Fe high-temperature shape memory alloys containing 0-1.0 wt.% La2O3 were fabricated by vacuum arc remelting to investigate oxide-dispersion effects on microstructure, martensitic transformation, wear, and corrosion behavior. XRD and SEM analyses revealed that low La2O3 additions (0.2-0.4 wt.%) promoted β1′ martensite refinement and enhanced crystallinity, while higher contents induced structural heterogeneity. The alloy with 0.4 wt.% La2O3 exhibited the highest transformation enthalpy (7.49 J g−1), reduced friction coefficient (~0.55), and the narrowest wear scar (~501 µm). Electrochemical tests in 3.5 wt.% NaCl showed a fivefold decrease in corrosion current density and increased charge-transfer resistance (2512 Ω cm2) for the same composition. Excessive La2O3 led to performance degradation due to particle agglomeration and interfacial defects. The results demonstrated that controlled La2O3 addition enabled microstructural refinement and multifunctional performance enhancement in Cu-based shape memory alloys.
- MakaleAçık Erişim2026Scopus SJRQ1Path Dependence and Spatial Spillovers in Regional Digitalization: Evidence from Dynamic Spatial Panel Analysis in Europe
Kazar, Görkemli; Kazar, Altuğ
Digitalization is the driver of regional competitiveness and sustainable development, but its geographical impacts differ significantly across Europe. This study was conducted to determine if digital transformation results in regional sustainability or if it increases spatial inequalities, concentrating on European NUTS-1 regions for the period 2021–2025. A composite Regional Digitalization Index was developed by means of Principal Component Analysis (PCA) based on indicators measuring internet access, internet usage, and the availability of digital public services. Dynamic spatial panel econometric models were used for empirical investigation, including a Spatial Autoregressive (SAR) model and a Spatial Durbin model (SDM), which facilitated the exploration of both temporal dependence and spatial spillover. Three main conclusions can be derived from the results, as follows: The level of digitalization in a region is highly stable over time, whereby the development depends most on previous paths. Subsequently, human capital is highly significant for digital development, and its effects are not only local but also spill over to neighboring regions. Lastly, spatial interactions consist of two opposite forces—the positive diffusion from digitally advanced neighboring regions and the competitive effects related to the economic strength of neighboring regions—that further intensify the core–periphery divide.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ1Effect of dilute rare-earth addition on structural evolution, mechanical, magnetic, and radiation shielding properties of CoFeNiMnTi high-entropy alloy
Özkul, İskender; Kalay, Ece; Güler, Ömer; Karaduman, Oktay; Canbay, Canan Aksu; Hameed, Louis Ibrahim; Almisned, Ghada; Baykal, Duygu Sen; Tekin, H.O.
This study investigates the effect of 1 at.% rare-earth (RE = Sm, Gd, Dy) addition on the structural, mechanical, magnetic, and radiation shielding properties of CoFeNiMnTi high-entropy alloys produced by arc melting. X-ray diffraction results reveal an FCC-dominant structure accompanied by secondary Laves-type phases, with increased phase complexity observed in Gd- and Dy-containing alloys. Mechanical evaluation shows a significant hardness enhancement, reaching 581 HV for Gd and 548 HV for Dy, compared to 447 HV for the reference alloy. Magnetic measurements indicate soft-ferromagnetic behaviour for all compositions, with magnetization increasing in the order S0<S1<S2<S3, highlighting the strong influence of Dy on magnetic response. Elemental mapping confirms a homogeneous distribution with minor local compositional variations contributing to phase evolution. Thermodynamic analysis suggests that rare-earth addition increases lattice distortion and chemical complexity without strongly differentiating among RE types. In terms of radiation shielding, linear attenuation coefficients and effective atomic number values demonstrate improved gamma-ray attenuation, particularly at low energies, with Dy exhibiting the highest performance. In contrast, fast neutron removal cross section values remain nearly unchanged, indicating limited sensitivity to dilute RE addition. It can be concluded that the incorporation of Dy results in the most balanced multifunctional performance, whereas Gd primarily enhances mechanical strength, emphasizing the importance of rare-earth selection in the design of high-entropy alloys for radiation-related applications.
- MakaleAçık Erişim2026Scopus SJRQ1Multi-Response Kinetic Modeling of the Maillard Reaction in Milk During Heating at Ultra-High-Temperature Range
Hamzalıoǧlu, Aytül; Aktaǧ, Işıl; Gökmen, Vural
This study developed first a comprehensive multiresponse kinetic model to elucidate the mechanism of the Maillard reaction in milk during ultrahigh-temperature treatment. The model incorporates the alterations in precursors (sugars, amino acids), intermediates (α-dicarbonyl and Amadori compounds) and products (N-ε-carboxymethyllysine, N-ε-carboxyethyllysine) that occur in milk during heating between 110 and 140 °C. Kinetically important reactions steps were identified by multiresponse kinetic modeling. Results indicated that N-ε-carboxymethyllysine and N-ε-carboxyethyllysine were formed predominantly by the oxidation of lactulosyllysine. Among the intermediates, the formation of 1-deoxyglucosone and glucosone, and methylglyoxal from 1-deoxyglucosone and glyoxal from glucosone, were determined to be the kinetically important steps. The rate-limiting step was identified as lactulosyllysine formation, while methylglyoxal generation occurred most rapidly across all heating temperatures. In this study, the multiresponse kinetic modeling approach was applied to milk, offering a comprehensive understanding of the critical pathways leading to the formation of α-dicarbonyl compounds and advanced glycation end-products.
- MakaleAçık Erişim2026Scopus SJRQ1Dietary exposure and health risk assessment of fumonisins through the consumption of maize and maize-based gluten-free products in individuals with celiac disease
Tuyben, Eylem Ezgi; Sevim, Sumeyra; Macit, Arife; Kizil, Mevlude
Introduction: Individuals with celiac disease (CD) must adhere to a gluten-free diet (GFD) and are therefore at high risk of fumonisin exposure due to their high consumption of maize and maize-based products. This study aimed to determine the concentrations of fumonisins (FB1, FB2, and FB3) in packaged gluten-free (GF) maize and maizebased products sold in Turkey and to assess dietary exposure and health risks in adults with CD using a probabilistic approach. Methods: Fumonisin concentrations of 51 GF products were analyzed by Enzyme-Linked Immonosorbent Assay (ELISA) and daily food consumption data were collected from 67 individuals with CD through a food frequency questionnaire. Exposure was estimated using Estimated Daily Intake (EDI) values and probabilistic risk assessment with Monte Carlo simulation. Results: The highest fumonisins concentrations were detected in the pasta/rice/bulgur group, while the flour/starch group was the food group contributed most to total fumonisins exposure due to higher consumption. Although the average EDI values were below the Tolerable Daily Intake (TDI; 1 μg/kg bw/day) set by European Food Safety Authority’s (EFSA) and Provisional maximum tolerable daily intakes (PMTDI; 2 μg/kg bw/day) established by Joint Expert Committee on Food Additives’s (JECFA) values, individuals at the 95th percentile approached 132.88–167.89% of the PMTDI value in the flour/starch group and 79.00–82.38% in the pasta/rice/bulgur group. Discussion: These findings highlight the need for continuous monitoring and stricter regulatory oversight and dietary guidance to protect vulnerable populations.
- MakaleAçık Erişim2026Scopus SJRQ2Tribological Performance of SPS-Fabricated Cu-HEA/Gr Composites Under Current-Carrying Sliding Contact
Ozkaya, Serdar; Çelebi, Müslim; Yanar, Harun; Karabacak, Abdullah Hasan; Çelik, Ertuğrul; Güler, Onur; Coskun, Abdulkadir; Sekban, Dursun Murat
Cu-based hybrid composites reinforced with AlCrFeCuNi high-entropy alloy (HEA) particles and graphene were successfully fabricated by spark plasma sintering (SPS) to investigate the combined effects of microstructure, mechanical properties, and tribological performance under electrical current. Microstructural observations revealed a dense and homogeneous distribution of HEA particles within the Cu matrix, while the addition of 2.0 wt.% graphene promoted noticeable grain refinement due to its grain boundary pinning effect. Although graphene addition provided beneficial effects in terms of grain refinement and electrical conductivity, it also increased the porosity from 2.49% to 5.08%. Consequently, the beneficial contribution of graphene to mechanical strengthening was substantially offset by the adverse effect of increased porosity, resulting in only a marginal increase in hardness from 127 HB to 129 HB. The addition of 2.0 wt.% graphene led to a pronounced change in the tribological behavior of the composites. The Cu–HEA exhibited relatively stable friction behavior but experienced a higher wear rate under all test conditions. In comparison, the Cu–HEA–2.0 Gr composite demonstrated a lower coefficient of friction and wear rate at 0–10 A, which is consistent with the possible formation of a graphene-rich lubricating surface layer. A clear transition occurred at 30 A, where the coefficient of friction and wear rate began to increase, while at 50 A, further increases in both parameters were observed, suggesting progressive disruption of the proposed protective surface layer under the investigated current-carrying sliding conditions.
- MakaleAçık Erişim2026Scopus SJRQ1EBA-Net: A hybrid EfficientNetB3-BiLSTM-Attention model for species-level diatom classification
Balo Utku, Esen Damla; Kutlu, Banu; Utku, Anil
Species identification in diatoms is important for assessing water bodies, determining environmental quality, and analyzing biodiversity. Nonetheless, diatom classification has proven difficult due to intra-class variation, interclass similarity, and data imbalance in microscopic images. In this regard, we propose a new deep learning approach for species-level diatom classification. Various deep learning models, including traditional convolutional neural networks or CNNs (ResNet50, DenseNet121), state-of-the-art CNNs (EfficientNetB3, Xception, MobileNetV3), transformer-based architectures (ViT-B16, Swin-Tiny), and our proposed EBA-Net (EfficientNetB3-BiLSTM-Attention Network), were extensively compared under identical experimental settings. The EBA-Net integrates the advantages of convolutional feature extraction, sequence modeling, and an attention mechanism to improve classification accuracy. It first uses the EfficientNetB3 model as the backbone network to obtain higher-level features, followed by a BiLSTM layer to capture dependencies among the extracted features. Then, it applies the attention mechanism to the BiLSTM output to highlight the most informative features. Experimental results showed that the proposed EBA-Net model outperforms other models considered in the study, yielding 95.8% accuracy and 85.1% macro F1-score. In addition, Top-3 (98.9%) and Top-5 (99.6%) accuracies confirmed the efficiency of the proposed model for classifying objects from visually similar classes. An analysis of the model's interpretability was conducted using Gradient-weighted Class Activation Mapping, showing that the proposed model's attention is concentrated on relevant morphological features of diatoms. To the best of our knowledge, the suggested approach achieves state-of-the-art accuracy on the data set of diatoms used.
- MakaleYalnız künye2026Scopus SJRQ2Damage diagnosis in CFRP/Al7075-T6 aeronautical structures using piezoelectric sensors: characterization and experimental monitoring
Gahlouz, Ibtissem; Guemmour, Mohamed Boutkhil; Chellil, Sadek; Chellil, Ahmed; Houari, Amin; Aribi, Chouaib; Polat, Alper; Adjout, Warda; Bey, Mohamed
Purpose – This study aims to design a damage detection and characterization system (targeting cracks and delamination) for aeronautical composite structures. Design/methodology/approach – This methodology relies on a multidisciplinary approach combining polymer-reinforced/metallic carbon fiber hybrid structures with an integrated network of PZT sensors. It leverages experimental data and employs advanced signal processing and imaging techniques to monitor structural integrity and assess the severity of damage. Findings – Verified experimental results confirm the method's reliability in real-life situations. Research limitations/implications – Research Limits: “The primary challenges involve signal processing complexity due to the hybrid nature of AL7075-T6 and CFRP materials, as well as the potential influence of environmental factors (temperature, pressure) on PZT sensor reliability”. Research Implications: “This work enables a shift toward condition-based maintenance, significantly reducing operational costs while enhancing structural safety and extending the service life of critical aerospace and maritime assets.” Practical implications – This study enables a shift from scheduled to real-time structural monitoring. There is a drastic reduction in inspection time and aircraft downtime. Monitoring the fatigue of hybrid AL/CFRP structures helps to safely extend their service life. The study helps in providing precise diagnostics to optimize repair strategies and minimize human error. Social implications – There is a drastic reduction of structural failure risks through early-stage damage detection. Cost savings in maintenance can lead to more affordable air travel for the general public. The study helps in promoting a circular economy by safely extending the lifespan of complex structures and reducing material waste and also in shifting maintenance roles toward high-tech data analysis and specialized software expertise. Originality/value – The study investigates the complex damage mechanics at the interface of AL7075-T6 and CFRP laminates and helps in combining PZT sensor networks with advanced imaging software for real-time damage characterization. Beyond mere detection, the system assesses “structural criticality, ” providing high-value diagnostic data for maintenance optimization and cost reduction.
- MakaleAçık Erişim2026Scopus SJRQ4INTEGRATED BIOLOGICAL TREATMENT AND ELECTROCOAGULATION FOR SLAUGHTERHOUSE WASTEWATER: A NOVEL APPROACH USING FRESHWATER SNAILS (Viviparus contactus, Planorbis rubrum, Melanoides tuberculata)
Öğedey, Ayşenur; Kocabaş, Filiz Kutluyer; Kizak, Volkan; Kocabaş, Mehmet; Benzer, Fulya; Erişir, Mine; Öğedey, Hayrullah
As a potential pollution source, slaughterhouse wastewater (SWW) with development of the meat production and processing sector is a threat in the world. Therefore, the determination of economical, favourable, cost-effective and proper treatment method is crucial for sustainable environmental protection. This study focused on the performance and efficiency of a two-stage process combining biological treatment (BT) with freshwater snails and electrocoagulation (EC) of SWW. Viviparus contectus, Planorbis rubrum, Melanoides tuberculata were used in primary treatment while secondary treatment was realized with EC process. The EC of SWW was performed for reducing both turbidity and chemical oxygen demand (COD) concentration to levels compliant with direct-discharge regulations. In addition, the stirring speed, current density, initial pH and reaction time were assessed for evaluation the optimum EC condition. Oxidative stress biomarkers and some antioxidants were assessed in freshwater snails exposed to SWW after 24 and 96 h. The best removal efficiencies of COD (91.43%) and turbidity (92.42%) were obtained at pH 5 and 20 min of operational time by P. rubrum. Notably, MDA (Malondialdehyde) was highest level in M. tuberculata compared to V. contectus and P. rubrum. Overall, removing organic and inorganic pollutants from SWW could be provided with the hybrid process BT/EC as a combining approach.
- MakaleYalnız künye2026Scopus SJRQ1Mechanical and durability properties of sustainable alkali-activated mortars with ceramic insulator waste and andesite powder as partial substitutes for GBFS
Cemalgil, Selim; Yön, Merve Şahin; Dener, Murat; Karataş, Mehmet
This study explores the use of andesite powder (AP) and ceramic waste powder (CWP), derived from discarded electrical insulators, as supplementary precursors to ground granulated blast furnace slag (GBFS) in alkali-activated self-compacting mortars. The originality of the work lies in the combined utilization of these regionally sourced aluminosilicate wastes in binary and ternary binder systems, aiming to reduce GBFS dependency while ensuring adequate mechanical and durability performance. AP and CWP were used to replace GBFS at up to 50%, and the mixtures were evaluated for flowability, mechanical strength, density, porosity, water absorption, and capillary sorptivity. Durability was assessed through freeze–thaw cycling and high temperature exposure, and microstructural characteristics were examined using scanning electron microscope analysis. Results showed that while partial substitution with AP or CWP reduced compressive strength compared to the GBFS control, the incorporation of CWP in ternary systems partially compensated for the strength losses associated with AP. High temperature resistance improved markedly with increased CWP content; at 900°C, the 50% CWP mixture retained 44% of its original compressive strength, in contrast to 8% for the control. Although all mixtures containing waste exhibited reduced freeze–thaw resistance, mortars containing CWP exhibited superior performance compared to those with only AP. These findings highlight the potential of CWP, particularly in ternary systems, for developing sustainable alkali-activated mortars.
AtıfScopus16WoS14OpenAlex12İncele - MakaleYalnız künye2026Scopus SJRQ2Investigation of the effect of ultrasonic assisted milling and minimum quantity lubrication methods on the machinability of Hardox 500 steel
Dalgıç, Aras; Mahmat, Aybars
Hardox steel is widely used in agriculture, mining and transportation due to its mechanical properties such as high wear resistance, high impact resistance, high hardness, high durability and long life. The machinability of Hardox 500 is difficult as its high hardness and wear resistance lead to tool wear and low machining speed. Recently, various processing and cooling methods have been developed to increase machinability. Ultrasonic assisted milling (UAM), one of these methods, is a method used as an alternative to conventional milling (CM) in the milling of traditionally difficult-to-machine materials. In addition, minimum quantity lubrication (MQL) is a cooling method used to provide lubrication and cooling in the cutting area. In this study, the impacts of machining method, feed rate and spindle speed on cutting force, surface roughness and tool wear in milling of Hardox 500 steel were investigated. In the MQL method, mixtures with nano-sized SiC particles were obtained and applied to the cutting area. In the study, MQL reduced cutting forces by up to 19 %, surface roughness by 18 %, and tool wear by 30 % compared to dry machining, while UAM further decreased cutting forces by 17 %, surface roughness by 15 %, and tool wear by 12 % compared to CM. These results demonstrate that MQL and UAM significantly enhance machining performance over conventional and dry methods.
- 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.
- MakaleAçık Erişim2026Scopus SJRQ2Corrosion behavior and constant load scratch adhesion properties of CeO2 doped ceramic composite layer via micro arc oxidation on Al 1050 alloy
Ayday, Aysun; Durmaz, Mustafa; Duru, Erhan; Kırsever, Derya; Doğan, Fatih
In this study, CeO2-doped ceramic coatings were produced on Al 1050 alloy by micro-arc oxidation (MAO) using a silicate-alkaline electrolyte containing 0, 0.5, 1, and 2% CeO2. The aim was to investigate the effect of CeO2 addition on the microstructure, phase composition, corrosion behavior, and constant-load scratch adhesion performance of the coatings. Surface characterization was carried out by SEM, EDS, XRD, and 3D profilometry, while corrosion performance was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy in 3.5 wt% NaCl solution. Scratch tests were also performed to assess the mechanical integrity of the coatings. The results showed that increasing CeO2 content improved coating uniformity, reduced surface roughness and porosity, and promoted the formation of a denser oxide structure. XRD analysis confirmed that γ-Al2O3 was the predominant alumina phase in all coatings, while Ce-containing species were incorporated into the oxide layer without forming additional detectable phases. Electrochemical results revealed that CeO2 addition significantly improved corrosion resistance by lowering the corrosion current density and increasing the polarization resistance. Scratch test results further showed improved adhesion-related behavior with reduced crack formation and surface damage. Overall, CeO2 addition effectively enhanced both the corrosion protection and mechanical performance of MAO coatings on Al 1050 alloy.
AtıfScopus1OpenAlex1İncele - 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.
- MakaleYalnız künye2026Scopus SJRQ1Sufi thought in the diwan of the French Christian poet Charles Vernay
Kayaokay, İlyas
This article examines how the French Christian poet Charles Vernay (1842–1866) engaged with Ottoman Sufi poetic discourse in his Divan-ı Verne (1858), a collection of poems written in Ottoman Turkish and Persian. While openly preserving his Christian identity, Vernay frequently employs key Sufi concepts, including ‘tevhid’ (divine unity), ‘aşk-ı hakiki’ (mystical love), ‘irfan’ (gnosis), ‘hakikat’ (truth) and the ‘tarik’ (spiritual path). Through a close textual analysis of selected poems, this study explores the relationship between Vernay’s Christian identity and the Sufi vocabulary that shapes his poetic imagination. The findings demonstrate that Vernay’s use of Sufi terminology extends beyond conventional imitation of classical Ottoman poetry. He employs these concepts to articulate his own spiritual worldview while simultaneously referring to the Bible, Jesus Christ and the doctrine of the Trinity. Although Vernay adopts the metaphysical language of Ottoman Sufism, he does not reproduce its Prophet Muhammad-centred framework. Instead, he reinterprets Sufi concepts within a Christian religious horizon and constructs a spiritual discourse shaped by unity, love, truth and faith. Divan-ı Verne thus reveals how Ottoman Sufi poetic language could be appropriated across religious boundaries and provides new insight into intercultural literary exchange in the nineteenth-century Ottoman world.
- MakaleAçık Erişim2026Scopus SJRQ1Impact of Postharvest Oxalic Acid Treatments on Quality Properties and Biochemical Composition of Medlar (Mespilus germanica L.) Fruit
Çolak, Ayşen Melda; Gündoğdu, Özlem; Aglar, Erdal; Sezgin, Nevzat; Orman, Erdal; Gundogdu, Muttalip
This study was conducted to investigate the effects of oxalic acid (OA) applications at different concentrations on the quality traits and biochemical components of medlar (Mespilus germanica L.) fruit. Fruits harvested in Bolu province in 2024 were subjected to control (0) and 0.5, 1.0, and 1.5 mM OA applications and stored at 4°C and 90% ± 5% relative humidity for 45 days. Samples were taken from the fruits at certain intervals (0, 15, 30, and 45 days) and analyzed. Specifically, 1.0 and 1.5 mM OA applications significantly reduced fruit weight loss and decay rates. OA also inhibited increases in fruit respiration rate and pH and slowed the decline in total acidity, soluble solids content (SSC), vitamin C, phenolic compounds, and organic acids. Malic, citric, succinic, tartaric, and fumaric acids, vitamin C, and important phenolic compounds (chlorogenic acid, gallic acid, quercetin, catechin) were protected by OA applications, and this protection was most pronounced at 1.5 mM OA dose. The correlation analyses revealed significant relationships between quality parameters and biochemical contents. The weight loss and decay rate were negatively correlated with bioactive compounds such as gallic acid and ascorbic acid, indicating that quality deterioration progressed in parallel with the decrease in nutrient content. A strong positive correlation was found between titratable acidity and malic and citric acids. In principal component analysis (PCA), malic and citric acids were prominent in the early storage period, while weight loss, decay, and increased respiration became dominant in the late storage period. Phenolic compounds decreased significantly with storage time, and antioxidant capacity decreased. Heat map analysis visually supported the increase in spoilage parameters with the decrease in ascorbic acid and phenolic compounds. OA applications maintained the quality of medlar fruit and increased biochemical stability, extending postharvest life. 1.5 mM OA, in particular, stands out as an effective postharvest preservation method. These results demonstrate that OA offers significant potential for increasing the commercial value of perishable fruits like medlar and for developing preservation technologies.
AtıfScopus1OpenAlex1
İncele - MakaleAçık Erişim2026Scopus SJRQ1Numerical analysis of PCM integrated in solar dryers for thermal efficiency
Bakır Gür, Eda; Işık, Erdem; Uçar, Aynur
Solar dryers using phase change materials buffer heat, yet the combined influence of airflow regime and PCM placement on melting remains underexplored. A controlled like-for-like study fixed geometry and PCM properties while varying placement and operating conditions. A 3D transient CFD model simulated a forced-convection dryer with RT28HC over Re = 3000–9000 and inlet temperatures Ti = 50–60 °C. Raising either Re or Ti shortened melt time, and three-wall coverage melted faster and more uniformly than a rear-wall-only layout. For three walls, melt time dropped from 13 h (50 °C, Re = 3000) to 7 h (60 °C, Re = 9000) (−46 %) for the rear wall it fell from 19 h to 11 h (−42 %). A 10 °C increase in Ti reduced overall melt time by 4 h across Re. Practically, three wall PCM with Re ≥ 6000 at Ti = 60 °C achieved reliably 7–9 h melting, enabling late afternoon heat release without auxiliary heating.
AtıfScopus17WoS16OpenAlex12İncele - MakaleAçık Erişim2026Scopus SJRQ2Engineering Superior Soft Magnetic Properties Through FeCo/Cr and FeCo/Fe Nanocrystalline Architectures
Yüzüak, Gizem Durak
Soft magnetic materials are integral to various technologies, including high-frequency transformers, spintronic devices, and magnetic sensors, because of their low coercivity (HC) and high magnetization. This study investigates nanocrystalline Fe70Co30(100 nm)/Cr(2-10 nm) and Fe70Co30(100 nm)/Fe(2-10 nm) thin films, deposited via magnetron sputtering. X-ray diffraction analysis reveals that Fe70Co30 films without buffer layers crystallize in a body-centered cubic phase. The Cr and Fe buffer layers enhance it by minimizing lattice mismatch and promoting a uniform crystalline growth of the Fe70Co30 layer. The most significant particle size variations observed were approximately 24% for the Cr buffer and 31% for the Fe buffer. Microstructural characterization using atomic force microscopy and scanning electron microscopy identified nanograins with an average size of 30–80 nm. Magnetic characterization with a vibrating sample magnetometer showed a marked reduction in HC. Additionally, the remanence-to-saturation magnetization ratio remains nearly constant at 0.95 across all Fe-buffered films, whereas it increases from 0.80 to 0.92 in Cr-buffered films as the Cr thickness increases. The results highlight the importance of buffer layer engineering in enhancing the microstructural and magnetic properties of FeCo thin films, thereby increasing their suitability for advanced magnetic technologies.
- MakaleAçık Erişim2026Scopus SJRQ1Biogenic amine profiling of fruit wines by high-performance liquid chromatography with fluorescence detection after OPA derivatisation: effect of fruit type
Tok, Fırat; Çetin, Burcu; Karaca Sanyürek, Nesrin
This study aimed to characterise the biogenic amine (BA) profiles of fruit wines produced from different raw materials and to investigate their association with pH and fruit type. Ten commercially available fruit wines, including pomegranate, black mulberry, sour cherry, strawberry, melon, blackberry, and blueberry, were analysed using HPLC with fluorescence detection (HPLC-FLD) following pre-column derivatisation with o-phthalaldehyde. Putrescine, tyramine (TYR), and histamine were identified as the predominant amines, with total BA concentrations ranging from 11.62 to 53.96 mg/L depending on the fruit type. The pH values of the wines (3.28-3.60) were inversely related to acidity and showed a strong positive correlation with total BA content (r = 0.97, p < .001). Among the detected compounds, TYR exhibited the highest sensitivity to pH variation. Multivariate analysis using principal component analysis clearly differentiated the samples into two distinct groups: low pH-low BA wines (pomegranate and blueberry) and high pH-high BA wines (blackberry and strawberry). The HPLC-FLD method demonstrated excellent analytical performance, with high chromatographic stability (retention time RSD < 1%) and reliable compound identification. Overall, the results indicate that BA formation in fruit wines is closely associated with both pH and fruit type, reflecting the combined effects of raw material composition and fermentation conditions. These findings provide valuable insights into the biochemical characterisation, quality assessment, and safety evaluation of fruit wines in oenological applications.