Yazarlar
- Yildirim, Numan(27)
- Tanyol, Mehtap(21)
- Topal, Murat(19)
- Kutlu, Banu(18)
- Yildirim, Nuran Cikcikoglu(17)
- Ince, Muharrem(16)
- Serdar, Osman(16)
- Erguven, Gokhan Onder(14)
- Öbek, Erdal(14)
- Danabas, Durali(13)
- Acar, Ramazan(11)
- Demir, Veysel(11)
- Arslan Topal, E. Işıl(8)
- Ogedey, Aysenur(8)
- Yonten, Vahap(8)
- Tatar, Sule(7)
- Ince, Olcay Kaplan(6)
- Aksu, Onder(5)
- Alp, Hevidar(5)
- Ates, Mehmet(5)
- Korkmaz, Volkan(5)
- Oguz, Ensar(5)
- Topal, E.Işıl Arslan(5)
- Ural, Mesut(5)
- Arslan, Zikri(4)
- Aslan, Naim(4)
- Can, Erkan(4)
- Demirbilek, Deniz(4)
- Goksu, Ali(4)
- Kocabaş, Mehmet(4)
- Korkmaz, Meral(4)
- Kurnaz Yetim, Nurdan(4)
- Lassabatere, Laurent(4)
- Mutlu, Ekrem(4)
- Yilmaz, Deniz(4)
- Akkurt, Nevzat(3)
- Angulo-Jaramillo, Rafael(3)
- Arslan Topal, E.I.(3)
- Aydın, Ayşe Nur(3)
- Camas, Mustafa(3)
Yayınlar
- MakaleAçık Erişim2026Seasonal changes in oxidant and antioxidant biomarkers in liver and muscle of common carp (Cyprinus carpio) in Atatürk Dam Lake
Benzer, Fulya; Tepe, Rıdvan; Erisir, Mine; Turkoglu, Semra; Fırat, Özgür; Şahin, Ayse Gül; Sünbül, Muhammet Raşit; Örnekci, Gürel Nedim; Küçükyılmaz, Mehmet; Öz, Özden Barım
Seasonal investigations were conducted on 640 Cyprinus carpio specimens obtained through commercial fishing at four different stations (Gerger, Sitilce, Hosirge, and Samsat) in the Atatürk Dam Lake. MDA (malondialdehyde) levels were measured in the liver and muscle tissues of male and female fish; the results revealed a significant increase in MDA levels at stations exposed to point-source discharge. This indicates that pollution-induced oxidative stress in fish varies significantly across seasonal and regional scales. Among the stations compared, the lowest MDA values were detected in fish tissues from the Gerger station, while the highest values were recorded at the Sitilce and Hosirge stations. Analysis of SOD, GSH-Px, and GSH values across all stations showed that these parameters fluctuated in correlation with MDA levels thereby maintaining the oxidant-antioxidant balance. This study investigated seasonal and spatial variations in oxidative stress biomarkers in common carp (Cyprinus carpio) collected from four stations in Atatürk Dam Lake. A total of 640 specimens were analyzed for malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and reduced glutathione (GSH) levels in liver and muscle tissues. Results showed that MDA levels were significantly higher in fish collected from Sitilce and Hosirge stations, indicating elevated lipid peroxidation associated with point-source pollution. In contrast, the lowest MDA levels were observed at the reference station, Gerger. Antioxidant enzyme activities (SOD, GSH-Px, and GSH) exhibited tissue-, season-, and site-dependent variations, suggesting adaptive responses to oxidative stress. Overall, the findings demonstrate that anthropogenic pressures in Atatürk Dam Lake significantly alter the oxidant–antioxidant balance in fish, highlighting the usefulness of these biomarkers for environmental monitoring.
- MakaleAçık Erişim2026Investigation of heavy metal accumulation in Typha latifolia exposed to mine drainage waters
Tatar, Sule; Okuduci, Ebru
In this study, the accumulation of some heavy metals in water, sediment, and Typha latifolia plant species was investigated in a previously operated mining area located in the Hozat region of Tunceli. In the first phase of the study, water and soil samples were collected from sites where T. latifolia was dominant. The metal uptake capacities from soil to roots, stems, and leaves of the plants were examined for different metals as silver (Ag), barium (Ba), cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), strontium (Sr), zinc (Zn). Water, sediment, and plant samples collected from the field were analyzed for the above elements at ultra-low detection limits using ICP-MS at ACME Analytical Laboratories in Canada. Bioconcentration factors (BCF-R, BCF-S, BCF-L, respectively) for the root, stem, leaf, and translocation factor (TF) values were calculated. The highest TF value was found to be 0.85 for Sr. The highest bioconcentration factors in the root, stem, and leaves of the plant were also found to be 3.67, 1.55, and 1.79 for Sr, respectively. According to the results obtained, T. latifolia was found to be a suitable plant for the bioaccumulation of Cd, Pb, Cu, and Sr under the existing environmental conditions, but not a suitable bioaccumulator for Ag, Ba, Ni, and Zn. Based on the results, it was determined that some heavy metal pollutants can be remediated using certain plants, and that these plants can function as bioaccumulators for these metals.
- MakaleYalnız künye2026Scopus SJRQ2An Investigation of the Variability of Short-Term Drought with SPEI-Based Severity, Duration and Magnitude Parameters in a Transboundary Basin
Akbas, Ergun; Acar, Ramazan; Eşit, Musa; Koycegiz, Cihangir
Climate change-induced variability in the water budget leads to significant drought events. In this study, severity, duration, and magnitude parameters obtained from 1-month and 3-month series of the Standardized Precipitation Evapotranspiration Index (SPEI) were used to investigate short-term drought from different perspectives. The lower part of the Euphrates-Tigris Basin, which is a transboundary basin, was preferred as the study area within the borders of Türkiye. In this study, monthly total precipitation and monthly mean temperature data for the period 1963–2021 were used. Both graphical (Şen Innovative Trend Analysis) and statistical (Mann–Kendall, Spearman’s Rho, Sen’s Slope Estimator) trend analysis methods were applied to detect, categorize, and analyze the variability of drought. The Combination of Wilcoxon Test and Scatter Diagram (CWTSD) method, which offers both graphical and statistical trend analysis capabilities, was preferred to enhance consistency and facilitate comparison of results. According to the findings, more severe droughts are observed in the eastern part of the basin compared to the western part. Across the basin, severity and magnitude are decreasing, while duration is increasing. The increase in duration indicates that droughts are shifting from short-term to long-term periods. This situation is of great importance in terms of planning agricultural strategies.
AtıfOpenAlex3
İncele - MakaleAçık Erişim2026Scopus SJRQ1Geospatial evaluation of river basin small hydropower potential using AHP
Korkmaz, Meral
This study develops an integrated Geographic Information Systems (GIS) and Analytic Hierarchy Process (AHP) framework to accurately identify small hydropower plants sites that support sustainable water–energy planning. The approach is applied to the Peri River Basin in Eastern Türkiye by combining multisource remote sensing datasets with a semi-automated narrow-valley detection technique to enhance the spatial precision of site selection. Nine hydrological and physiographic criteria including stream order, rainfall, slope, geology, drainage density, elevation, land use land cover, Stream Power Index SPI and Topographic Wetness Index TWI were weighted using the AHP method to generate a five-class suitability map for small hydropower plants development. A major contribution of this study is the explicit integration of valley morphology into the conventional GIS–AHP workflow, which significantly improves the identification of hydropower favorable river segments. Results indicate that approximately 3% of the basin exhibits very high suitability, while 46% is moderately suitable for run-of-river small hydropower plants development. Model validation was performed by overlaying the suitability map with the locations of existing dams/hydropower facilities, showing that current facilities are mainly located in high-suitability zones. Separately, the workflow identified 13 newly proposed high-suitability candidate dam sites (P1–P13), selected from screened suitable dam points using narrow-valley detection criteria. By minimizing ecological disturbance and aligning with watershed-based management principles, the proposed GIS-supported multicriteria method provides a transferable and cost-effective decision-support tool for small-hydropower planning in rural and mountainous basins, offering practical contributions to sustainable resource management and the water–energy nexus.
AtıfScopus2WoS2OpenAlex4İncele - MakaleYalnız künye2026Scopus SJRQ2Comparative Analysis of Sequential Electrooxidation and Electrocoagulation Processes for Leachate Treatment
Ogedey, Aysenur; Oguz, Ensar
This study aims to improve the removal efficiency of chemical oxygen demand (COD), NH₃-N, and turbidity from Bingöl leachate through a sequential electrochemical process. This process includes electrooxidation (EO) with Ti/PdO-CoO anodes and stainless-steel cathodes, followed by electrocoagulation (EC) with aluminum anodes and stainless-steel cathodes. The sequential electrochemical process lasted 400 min, consisting of 360 min of EO followed by 40 min of EC process. At pH 5, COD and turbidity reached optimal removal efficiencies of 89% and 99.9%, respectively, while NH₃-N achieved 88.5% at pH 9.5. These results indicate that the sequential electrochemical process was most effective under these pH values for removing organic matter, nitrogen, and suspended solids. The sequential electrochemical process led to significant improvements in the removal efficiencies of COD, NH₃-N, and turbidity, with increases of 32.5%, 44%, and 6.9%, respectively, compared to the EO process. The sequential electrochemical process showed improvements of 9.5% in COD and NH₃-N removal, and 1.2% in turbidity removal, compared to the results of the EC process. The pseudo-first-order (PFO) reaction rates for the EO and EC processes were determined, resulting in high R2 values (0.98–0.99). Additionally, the total consumption cost of the EO process was higher than that of the EC process. After the sequential electrochemical process, the consumption cost increased from $13.586/kg COD to $24.332/kg COD as the current density increased from 15 mA/cm2 to 25 mA/cm2.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ2Adsorption of Reactive Red 120 dye from aqueous solutions using sepiolite clay with a channel-structured morphology: Mechanism, kinetics, isotherm, and thermodynamic studies
Fırat, Tülay
The effective treatment of dye-containing wastewater remains a major environmental challenge due to the high stability and solubility of reactive dyes. In this study, the adsorption behavior of Reactive Red 120 (RR120), an anionic reactive azo dye, from aqueous solutions was investigated using natural sepiolite clay possessing a channel-structured morphology. Batch adsorption experiments were performed to evaluate the effects of contact time (1–200 min), initial dye concentration (50–500 mg L−1), adsorbent dosage (0.1–1.5 g), solution pH (2–10), and temperature (25–50°C). The adsorption equilibrium was reached within approximately 75 min. The Langmuir isotherm provided the best fit to the equilibrium data, yielding a maximum monolayer adsorption capacity of 168.4 mg g−1 at 298 K. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic, with an activation energy of 32.41 kJ mol−1. Adsorption kinetics were analyzed using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, while equilibrium data were evaluated using Langmuir, Freundlich, and Temkin isotherm models. The kinetic data were best described by the pseudo-second-order model, while thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic. FTIR and XRD analyses further supported the important role of the channel-structured framework of sepiolite in RR120 adsorption. Unlike many clay-based adsorbents that require chemical modification, natural sepiolite exhibited high adsorption performance due to its intrinsic fibrous morphology, nano-channel structure, and high surface area. These findings demonstrate that natural sepiolite is a promising, low-cost, and sustainable adsorbent for the treatment of dye-contaminated wastewater.
- MakaleAçık Erişim2026Scopus SJRQ1The effect of hydrostatic water level on the local scour downstream of plunging aerated jets
Tunc, Mustafa; Aytac, Ayca; Tuna, M. Cihat; Acar, Ramazan
This paper reports an experimental study on the effect of hydrostatic water level on local scour downstream of plunge aerated jets. To examine the shape of the scour for non-cohesive bed material, different flow and air rates, and different aeration capabilities, hydrostatic water level circumstances were tested. The water jets were aerated using conduit systems with varying cover opening ratios. Measurements were made to determine the length of the scour hole, the value of the maximum scour depth, the location of the maximum scour depth, and the scour hole profile in equilibrium. The current findings show that downstream hydrostatic water levels have a significant impact on the maximum depth and area of scour. Additionally, it was discovered that the conduit gate opening ratio and aeration performance (Qa/Qw) are crucial factors that affect the geometry and diameters of scour holes. The properties of scour caused by various hydrostatic levels were systematically compared to develop empirical correlations for predicting the maximum scour depth. Consequently, predictive emprical formulas incorporating these hydrostatic variations and aeration parameters are presented to improve engineering design accuracy.
- MakaleAçık Erişim2026Scopus SJRQ3Optimized 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.
- MakaleAçık Erişim2026Scopus SJRQ2Synergistic 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.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2026Scopus SJRQ2Using Decision Tree and K-Means to Improve ANFIS for Predicting Missing Flow Data in Çoruh Basin
Acar, Ramazan
Complete and continuous flow data provides contributions to the water resources projects appropriate design. However, both financial and technical factors prevent the regular collection of data and such a situation leads to missing data problems. Input variables are from five stations in the Çoruh Basin in the northeast province of Türkiye, and output variables are from one station. In the study, 75% (171 months of data) of the 228 months flow data between the years 1993–2011 are used in the training phase and 25% (57 months of data) in the testing phase. In the ANFIS models, Decision Tree (DT) and K-means (KM) methods are used in selecting the input variables and determining the number of membership functions. In addition, artificial neural network (ANN), multiple linear regression (MLR), and ANFIS models with randomly determined cluster numbers are also used to compare the model performance of these methods. The results show that using DT and KM methods, the ANFIS models generate more reliable results than other models. During the study, the regression coefficient (R2), weighted mean square error (WMSE), and Wilcoxon (Z) values are taken into account for reliability measure. The DT–K-means–ANFIS model achieved the highest accuracy with R2 = 0.98 and WMSE = 5.89 during the testing phase, demonstrating superior performance to the ANN and MLR models. It is shown that the most successful models can be determined in a shorter time by using DT and KM methods before generating ANFIS models.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ1Hydrogeochemical controls on chromium speciation and potential human health risks in surface waters of an ultramafic mining watershed
Kutlu, Banu; Baydar, Tarık; Yıldırım, Vesile; Konurhan, Zekeriya
Accurate assessment of chromium contamination in mining-influenced watersheds requires distinguishing between the environmentally contrasting Cr(III) and Cr(VI) species, yet environmental monitoring and risk assessments still rely predominantly on total chromium concentrations. This study evaluated whether chromium speciation provides additional information beyond operational total chromium for assessing chromium occurrence and potential human health risks in an ultramafic, mining-influenced watershed. Surface-water samples were collected from 28 sampling stations across the Pülümür and Ovacık regions of the Eastern Anatolia Basin (Türkiye) between March 2025 and February 2026. Chromium speciation was determined using species-specific UV–Visible spectrophotometric methods and integrated with hydrochemical characterization, multivariate statistical analyses, mineralogical investigations (XRD, SEM–EDS, and FTIR), and deterministic and empirical-bootstrap human health risk assessments. Operational total chromium, defined as the sum of separately measured Cr(III) and Cr(VI), ranged from below the detection limit to 578.13 µg L−1. For contextual screening, this calculated value exceeded World Health Organization (WHO) drinking-water guideline for total chromium at 14 stations; however, it was not an independently measured total-Cr concentration. The highest Cr(VI) concentration occurred at a localized hotspot, whereas Cr(III) predominated throughout most of the watershed. Nevertheless, Cr(VI)-based screening thresholds were exceeded at multiple stations under the assumed untreated drinking-water ingestion scenario, indicating that operational total chromium alone did not consistently identify the spatial distribution of Cr(VI)-related potential risk. Screening-level hazard quotient (HQ) estimates were higher for children than for adults; however, direct untreated consumption of the sampled surface waters was not verified. Mining-influenced stations generally exhibited higher chromium concentrations, although the relative contributions of geogenic weathering and mining-related mobilization could not be quantitatively apportioned. Overall, chromium speciation provided additional environmentally and toxicologically relevant information beyond operational total chromium for evaluating chromium mobility and screening-level potential human health risks in this ultramafic watershed.
- MakaleYayıncıda açık erişim2026Scopus SJRQ1Radon anomalies environmental radiation transfer and radiological risk assessment in a fault controlled Lake system
Dartay, Mürşide; Yılmaz, Mücahit; Kırat, Güllü
This study investigates the coupling between radon (222Rn) anomalies, seismic activity, hydrogeochemical transport, and radiological risk in Lake Hazar, an active fault controlled lake located along the East Anatolian Fault Zone (EAFZ), Türkiye. Soil gas and dissolved 222Rn concentrations were periodically monitored on a monthly basis from September 2024 to August 2025 using a DURRIDGE RAD7 detector coupled with RAD H2O accessories and the results were evaluated with regional seismicity within a 50 km radius. Natural radionuclide activities (40K, 238U, and 232Th) were determined using 2″ × 2″ NaI(Tl) well-type gamma spectrometry detector. 222Rn anomalies were assessed using μ + σ, μ + 2σ thresholds, the Standardized Radon Index (SRI), and the Dobrovolsky preparation radius model. Soil 222Rn ranged from 87.6 to 541.8 Bq/m3, with the highest value (SRI = 2.81) recorded in September 2024, approximately one month before the Mw 6.0 earthquake in October 2024. Although this temporal coincidence is consistent with previous observations reported for tectonically active regions, the present dataset does not allow a definitive causal interpretation. Dissolved 222Rn varied from 34.1 to 69.8 Bq/L and showed delayed but detectable responses during periods of Mw ≥ 5 seismic activity. Radiological indices calculated for fish tissues remained far below international safety thresholds: Hin and Hex were < 1, Raeq values were substantially lower than the recommended limit of 370 Bq/kg, and absorbed dose rates were below the global average value of 59 nGy/h reported by UNSCEAR. In addition, annual effective dose values from fish muscle consumption remained well below the public exposure limit of 1 mSv/year recommended by ICRP, and ELCR values were within the low risk range commonly used in environmental radiological assessments. These findings indicate that active fault controlled lake systems may provide integrated environmental settings where tectonic stress, 222Rn migration, aquatic radionuclide transfer, and radiological exposure processes interact. Novelty statement: This study presents an integrated environmental investigation of soil gas and dissolved water 222Rn variability, radionuclide transfer in aquatic biota, and radiological risk assessment within the tectonically active Hazar Lake system located on the East Anatolian Fault Zone (EAFZ), Türkiye. The novelty of the present study lies in the following aspects: • Simultaneous evaluation of soil and dissolved water 222Rn anomalies together with seismic activity in a fault controlled lake ecosystem. • Application of the Standardized Radon Index (SRI) approach for normalized temporal interpretation of radon anomaly behavior in both soil gas and aqueous environments. • Integration of tectonic hydrogeochemistry with environmental radioactivity and aquatic radionuclide transfer assessment. • Combined investigation of radon anomaly behavior and radionuclide accumulation in fish tissues within the same tectonically active environmental system. • Inclusion of radiological risk indices (Hin, Hex, Raeq, Iγ, AGED) together with internationally accepted reference values for environmental and public health interpretation. • Development of a multidisciplinary environmental monitoring framework linking lithospheric, hydrospheric, and biospheric processes in active fault controlled lake environments. To the best of our knowledge, this is among the limited studies combining 222Rn anomaly monitoring, aquatic radionuclide transfer, and radiological risk assessment within an integrated tectonic lake ecosystem framework.
- MakaleAçık Erişim2026Scopus SJRQ3Effect of mechanical activation on lithium and alkali cation release from dolomitic clay wastes of boron processing plant
Boylu, Feridun; Teker, Gülsen Obuz; Angur, Gafure Ersever; Ozdemir, Orhan; Çelik, Mehmet Sabri
With the significant increase in lithium demand and production, alternative resources such as lithium-bearing clays have increasingly attracted attention and have been considered as a potential source. In addition to conventional Li recovery methods such as acid treatment and roasting, more economical and environmentally friendly techniques such as mechanical activation followed by water leaching are also being considered. In Türkiye, wastes from boron processing plants, containing approximately 900 ppm of lithium and mainly of dolomitic clays and unrecovered boron minerals (~10-13% of waste), are considered as a potential lithium source. However, due to high dolomite and boron mineral contents, the waste material may release significant amounts of alkaline earth ions such as Na+, K+, Mg2+, Ca2+, and B2O3 during leaching, which may interfere with lithium extraction from the solution. In this study, the leaching behavior of lithium, alkali ions, and other possible elements (e.g., B2O3, Fe3+, and Al3+) from both raw clay waste and mechanically activated forms of this waste material was investigated in detail. The results showed that water leaching without sodium salt of activated waste samples achieves about 44.7–57.7% lithium recovery, yielding high lithium concentrations (80–115 ppm), low levels of alkali ions (4430 ppm Na+, 114 ppm K+, 20 ppm Ca2+, and 7 ppm Mg2+), and almost no detectable Fe3+ (<0.2 ppm) or Al3+ (0.07 ppm) ions. On the other hand, a single problem was encountered where 0.95 % of B2O3 concentrations did not decrease in water leaching at even room temperature.
- MakaleAçık Erişim2026Scopus SJRQ1Health risk assessment of heavy metal accumulation in fruits exposed to geothermal waters: a case study and global implications
Arslan Topal, E Işıl; Topal, Murat; Çelik, Erdal; Öbek, Erdal
BACKGROUND: The present study investigated the potential health risks of heavy metals (HMs) in the fruits and leaves of mulberry and sour cherry trees exposed to water from Sivas geothermal basin (Turkey). RESULTS: The target HMs were ranked according to their hazard index as: Cd < Pb < Zn < Cu < Ni < Mn < Cr. The total hazard index for mulberry and sour cherry fruits was calculated as 7.87 and 4.57, respectively, and was determined to be well above the safe threshold value of 1.0. At the same time, the calculated cancer risk values exceeded the established maximum limit (1.0 × 10−4) for Ni (6.4 × 10−3) in mulberry fruit and for Cr (1.15 × 10−3) in sour cherry fruit. Ingestion has been identified as the primary route of exposure. The study results showed that Cr and Ni metals were ranked in the order of mulberry fruit > sour cherry fruit > mulberry leaf > sour cherry leaf, and that for mulberry and sour cherry fruit. CONCLUSION: The findings indicate that edible foods exposed to geothermal waters may have adverse effects on human health. Furthermore, the study highlights the necessity of reducing water discharges from geothermal fields and implementing phytoremediation strategies to ensure food safety in geothermally active agricultural basins.
- MakaleAçık Erişim2026Scopus SJRQ2Green Chemistry Meets Advanced Materials: Synthesis and Adsorption Performance of Ti3CNTx MXenes for Basic Red 46 Dye Removal
Aydın, Ekrem; Çelik, Aytekin; Köse, Yusuf; Hasar, Halil
In this study, Ti₃CNTₓ MXene nanosheets were synthesized from Ti₃AlCNTₓ MAX phase via two selective Al-etching routes: (i) direct hydrofluoric acid (HF) treatment and (ii) in-situ HF generation using a LiF + HCl mixture. Both approaches were systematically compared to evaluate their effects on structural integrity, surface chemistry, and adsorption performance toward the cationic dye Basic Red 46 (BR 46). Comprehensive physicochemical characterizations—including SEM–EDX, XRD, XPS, Raman spectroscopy, AFM, contact angle analysis, and TGA—confirmed successful Al removal and MXene formation for both methods, with notable differences in surface terminations and layer morphology. Batch adsorption experiments were conducted across a wide range of pH values (2–11), temperatures (25–60 °C), contact times (0–90 min), adsorbent dosages (0.05–0.40 g), and initial dye concentrations (10–50 mg/L). The HF-etched Ti₃CNTₓ exhibited rapid adsorption, achieving 99.6% removal at pH 2 within 20 min, whereas the LiF + HCl-etched sample demonstrated superior performance at moderate-to-alkaline pH and maintained high efficiency at lower dosages. Langmuir isotherm fitting revealed maximum adsorption capacities of 19.24 mg/g (HF route) and 28.01 mg/g (LiF + HCl route), supporting monolayer adsorption on homogeneous sites. Temperature-dependent studies further indicated an endothermic and spontaneous adsorption mechanism. Overall, the LiF + HCl route offers a greener and safer alternative to conventional HF etching while delivering competitive adsorption performance, improved structural stability, and faster equilibrium. These findings highlight the potential of sustainably synthesized Ti₃CNTₓ MXenes as high-performance adsorbents for dye-laden industrial wastewater treatment.
AtıfScopus2WoS2OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ3Optimization and Modeling of Brilliant Yellow Removal Via Neodymium-Infused Polymeric Hydrogel: A Central Composite Design Study
Pıhtılı Yıldız, Güzin; Tanyol, Mehtap; Demir, Ferhat
This study investigates the adsorption performance of a neodymium (III)-reinforced Poly(acrylamide-co-N-vinylimidazole) hydrogel composite [P(AAm-co-NVI)/Nd3+] for the removal of brilliant yellow (BY) dye from aqueous media. The hydrogel structure and metal–polymer interactions were characterized using FT-IR, TGA, SEM, and XRD analyses. The adsorption process was systematically optimized using a central composite design (CCD) approach combined with response surface methodology (RSM). The CCD-RSM second-order model exhibited a good fit to the experimental data (R2 = 0.9350), as supported by ANOVA. Numerical optimization revealed a maximum removal efficiency of 99.13% at a hydrogel dosage of 0.08 g/100 mL, an initial BY concentration of 81.68 mg/L, and a contact time of 61.73 min. Langmuir and the Freundlich isotherms were used in modeling the adsorption data. When the correlation coefficients of both models were compared, it was observed that the Langmuir isotherm provided a better fit for adsorption. The enhanced adsorption performance is attributed to the presence of Nd3+ ions, which promote additional electrostatic interactions and coordination sites between the hydrogel matrix and anionic dye molecules. The results demonstrate that Nd3+-reinforced hydrogels can serve as efficient and tunable adsorbent systems, particularly when process parameters are optimized statistically.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ1RGO-CBPAC versus CBPAC for diluted leachate treatment: adsorption isotherms, kinetics and thermodynamics
Ogedey, A.; Oguz, E.
This study compares carbon-based activated carbon (CBPAC) and reduced graphene oxide-modified CBPAC (RGO-CBPAC) for removing COD, NH3–N, and turbidity from 1:4 diluted leachate from the Bingöl landfill site. Brunauer Emmett Teller (BET) analysis indicated severe micropore blockage in CBPAC after adsorption (887 → 0.76 m2/g), whereas RGO-CBPAC retained a higher surface area (908 → 23 m2/g) and mesoporous structure, demonstrating enhanced structural stability due to graphene incorporation. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM–EDX) confirmed the presence of surface functional groups and effective pollutant uptake, with RGO-CBPAC showing stronger surface–pollutant interactions. Zeta potential analysis showed pH-dependent surface charge behaviour, with CBPAC exhibiting amphoteric characteristics and RGO-CBPAC maintaining a more negative surface. After adsorption, both became more negatively charged, indicating the accumulation of negatively charged species. Kinetic analysis showed that COD adsorption on CBPAC followed pseudo-first-order and intraparticle diffusion models, whereas NH3–N and turbidity followed pseudo-second-order kinetics. In contrast, RGO-CBPAC exhibited pseudo-second-order and intraparticle diffusion behaviour for all pollutants, suggesting chemisorption with diffusion-controlled contributions. Adsorption equilibrium was best described by the Langmuir isotherm, yielding maximum capacities of 500 and 588 mg O2/g for COD, 17.5 and 36.5 mg/g for NH3–N, and 18.1 and 58.5 mg/g ((NH2)2H2SO4)/g for turbidity on CBPAC and RGO-CBPAC, respectively. Thermodynamic analysis demonstrated that COD and turbidity removal using RGO-CBPAC were spontaneous (∆G° < 0) and endothermic (∆H° > 0), whereas NH3–N removal remained non-spontaneous for both adsorbents. RGO incorporation significantly enhanced adsorption performance.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ1Optimization of scours downstream of conduit aerators
Arici, Erdinc; Tuna, M. Cihat; Aytac, Ayca; Acar, Ramazan; Tunc, Mustafa
Dams, wastewater treatment plants, and aquaculture areas often require aeration, making it crucial for hydraulic engineers to predict the physical properties of scour holes occurring on the downstream side of conduits. Conduit systems that provide high aeration performance necessitate multiple optimization studies to simultaneously maximize the scour parameters and the system’s physical properties. In this study, the physical parameters of conduit systems and downstream scour parameters were optimized using Artificial Neural Networks (ANN). The optimum system parameters were identified based on the experimental results through ANN-based optimization. Additionally, the real and optimal effects of the parameters on aeration performance and scour were determined. The results of the study demonstrated that ANN can be effectively used in studies aimed at optimizing the aeration performance and scour values of conduits. This study is the first to apply ANN for the simultaneous optimization of both aeration efficiency (Qa/Qw) and scour characteristics (dmax and δ) in a conduit-based hydraulic system. Previous studies have typically focused on either scour or aeration individually; this study integrates both through a multi-objective ANN model. The findings provide novel insights for the design and retrofitting of energy-dissipating conduit structures in high-head dam applications. Unlike traditional empirical or regression-based approaches, the ANN model captures complex, nonlinear relationships among multiple interacting hydraulic variables. It identified optimal parameter combinations — such as 70% gate opening, 1.30–1.50 m conduit length, and 9 mm air hole diameter — that improve both aeration and scour behavior. These outcomes offer direct applicability for real-world hydraulic system optimization.
AtıfOpenAlex1
İncele - MakaleYalnız künye2026Scopus SJRQ2Lithium Recovery from Boron Processing Wastes via Mechanical Activation-Assisted Water Leaching: Application of Planetary Milling
Boylu, F.; Obuz Teker, Gülsen; Ersever Angur, Gafure; Ozdemir, O.; Çelik, M.S.
In this study, a more sustainable, cost-effective, and environmentally friendly approach for selective lithium extraction via water leach assisted by planetary mill mechanical activation was applied on clayey wastes of the Kırka Boron Plant. A detailed systematic study on wastes was performed to optimize both mechanical activation and leaching conditions and to characterize the active powders by XRD, FTIR and EDS/EDX. The results show that lithium can be recovered at relatively low leach temperatures of 50–60°C and short leach times of 3–5 min, achieving leach recoveries of 44.71 (without salt addition) and 57.71% (with 20% salt addition, w/w) without the need for pre-concentration of the waste. Despite relatively low lithium recoveries, water leaching of activated powder produced remarkably low concentrations of co-leached ionic impurities less than 10 ppm Mg, 20 ppm Ca, and 250 ppm K, compared to significantly higher concentrations observed during 1 M acid leaching (9422 ppm Mg, 564.5 Ca, and 72.5 ppm K, upon 1 M acid leaching, respectively). The presence of Mg ions, in particular, is known to be highly detrimental competing ion in metal recovery processes. Therefore, the proposed method offers both economic and environmental advantages by enabling higher purity lithium recovery under much milder conditions.
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ1Removal of Reactive Blue 4 Dye from Aqueous Solution with Magnetic Fe3O4@Nd/Alg Beads
Karaaslan Ayhan, Nagihan; Seker, Seda
In this study, magnetic iron oxide@neodymium/alginate (Fe3O4@Nd/Alg) beads were prepared by ionic crosslinking with neodymium (Nd) ions, then subjected to heat treatment, and for the first time, effective removal of Reactive Blue 4 (RB 4) dye from aqueous solution was achieved with these beads. For this purpose, ideal adsorption conditions that significantly affect the removal of this dye were determined. The ideal adsorption conditions were determined as pH:5, contact time (t):60 min, amount of magnetic Fe3O4@Nd/Alg bead (m):10 mg, initial RB 4 dye concentration (C0):25 mg/L, temperature (T): 25 °C. Adsorption isotherm, kinetic and thermodynamic studies were carried out under the ideal adsorption conditions. The adsorption data was found to completely follow Langmuir model for RB 4 dye and the maximum adsorption capacity of RB 4 was found to be 263.16 mg/g. The adsorption kinetic data was found to be compatible with pseudo-second order and adsorption processes were explained by intraparticle diffusion. In adsorption thermodynamics studies, it has been determined that the nature of the adsorption reaction is spontaneous, endothermic and with increasing randomness. Furthermore, reuse studies of magnetic Fe3O4@Nd/Alg beads were carried out and it was determined that these beads could be used successfully up to 10 adsorption/desorption cycles.
AtıfScopus4WoS4OpenAlex4İncele
