Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Sustainable Recovery of Critical Raw Materials From Geothermal Igneous Systems: Geochemical, Mineralogical, and Techno-Economic Insights from the Dikili-Bergama Field (Western Anatolia, Turkiye)(Elsevier, 2026) Ayzit, Tolga; Baba, AlperThe sustainable co-extraction of critical raw materials (CRMs) with renewable geothermal energy offers a dual pathway to support the circular economy and low-carbon transition. In this study, an integrated geochemical and mineralogical approach is used to comprehensively assess the recoverable lithium (Li) boron (B), strontium (Sr) and other critical raw materials in the geothermal reservoirs of the Dikili-Bergama region Turkiye. A geochemical analysis was carried out by systematic sampling and multi-element testing of geothermal water and reservoir rock. Hydrogeochemical studies of the geothermal fluids indicated the presence of remarkable concentrations of B (4.6 ppm), Sr (2.8 ppm) and Li (1.2 ppm), suggesting the possibility of active leaching processes in the deposit. Mineralogical studies using X-ray diffraction (XRD) have revealed a number of secondary mineral phases, such as quartz and labradorite, indicating the interaction between water and rock. These interactions affect not only the permeability and porosity of the deposit, but also the mobilization and precipitation of CRMs. A techno-economic analysis will be used to identify potential synergies that could improve the economic feasibility of geothermal projects in the region. The Monte Carlo simulation has shown that the Dikili-Bergama geothermal reservoirs have a potential of similar to 712 tons of Li. In this study, the CRM potential that emerged during the geothermal energy exploitation process in the region was calculated. The temporality and the process of obtaining are completely related to the extraction technology. This offers the dual benefit of renewable energy and strategic mineral extraction, contributing to sustainable resource management in volcanic environments.Article Fractionation of Guaiacyl and Syringyl-Lignin Units Using Organic Solvent Nanofiltration(Elsevier, 2026) Croes, Tim; Dutta, Abhishek; Van Aelst, Korneel; Sels, Bert; Van der Bruggen, Bart; Cornet, IrisA major obstacle to employing the full potential of lignin-based aromatics is the fractionation of the monomers present in lignin, specifically the separation of guaiacyl (G) and syringyl (S) units, which possess nearly identical molecular weights (196 Da versus 166 Da) and dimensions, and identical functional groups. Such similarities make their separation highly challenging using conventional techniques and are generally considered beyond the capabilities of size-based membrane processes. This study examines the feasibility of organic solvent nano-filtration for fractionation of guaiacyl and syringyl units, and how membrane and process parameters affect separation of these two molecules. Sixteen commercially available membranes were tested with methanol and ethyl acetate as solvents. The results demonstrate that, despite the extreme similarity of the solutes, selective separation is achievable and is primarily governed by membrane material and solvent selection rather than the pore size-based molecular weight cut-off. Polyimide-based solvent-resistant membranes exhibited the highest selectivity, with a maximum observed separation factor of 3.33 obtained using a DuraMemTM 500 membrane in methanol. These findings demonstrate the potential of nanofiltration to address previously unresolved separation challenges in lignin valorization and provide a basis for further process development.Article Comparison of the Photoresponse Characteristics for 4H-SiC Schottky Barrier UV Photodetector with Graphene and Ni/Cr Electrode(Elsevier, 2026) Dulcel, Atilla Mert; Gozek, Melike; Unverdi, Ozhan; Celebi, CemGr/4H-SiC and Ni/Cr/4H-SiC Schottky junction UV photodetectors were fabricated and investigated to reveal the effect of electrode materials on the device performance such as spectral response and response speed. I-V characterization, spectral response, and response speed (on-off) measurements were conducted for the UV wavelength range between 200 and 400 nm. The maximum photo-responsivity was obtained as 0.081 A/W for Gr/4H-SiC and 0.041 A/W for Ni/Cr/4H-SiC at a wavelength of 260 nm. This result was attributed to the higher optical transmittance of the graphene electrode compared to the semitransparent Ni/Cr electrode. Zero bias response speed measurements were done under 280 nm wavelength UV light pulsed at different frequencies such as 100 Hz, 500 Hz, and 1000 Hz. The Gr/4H-SiC and Ni/Cr/4H-SiC photodetectors show distinctly different decay times of 5.04 ms and 305.1 mu s, respectively, while their rise times were found to be similar. This observation has been explained by the inclination of graphene to act as a trap site for photogenerated holes.Article Continuous Direct Lithium Extraction from Seawater Via an Unconventional Selective Solid Electrolyte(Elsevier, 2026) Li, Jinghui; Gao, Jiaxuan; Yu, Zihao; Yan, Linxue; Guo, Yafei; Demir, Mustafa; Deng, TianlongWith the significant depletion of terrestrial lithium resources, attention has shifted toward seawater, which holds the largest lithium reserves on Earth. However, extracting lithium from seawater presents a complex challenge due to its intricate composition and extremely low concentration of lithium ions. Herein, we demonstrated inexpensive Li4Ti5O12 as a selective solid electrolyte for direct lithium extraction from seawater. It extracted lithium ions from seawater at an initial concentration of 0.17 mg/L and enriched them to 22.25 mg/L in the receiving solution. The sodium and magnesium ion concentrations were only 33.5 mg/L and 0.66 mg/L. The Li/ Na selectivity (SLi/Na) and Li/Mg selectivity (SLi/Mg) were remarkably high, reaching 42,000 and 240,000, respectively. Furthermore, DFT showed that the energy required for both processes-desolvation of sodium ions and migration of ions within the crystal-is significantly higher than that for lithium ions, which explains the high selectivity of this method. XAS and XRD refinement revealed that the lithium-ion conductor remained stable without any decomposition. In addition, we designed a comprehensive process using the phase equilibrium method, enabling the direct separation of lithium hydroxide without waste when Li4Ti5O12 serves as the selective solid-state electrolyte, thereby highlighting its strong potential for industrial applications.Article Chloroaluminum Phthalocyanine Loaded Bovine Serum Albumin Nanoparticles as a Dual-Functional Nanoplatform for Sono-Photodynamic Cancer Therapy(Elsevier, 2026) Akyol-Karpuzcu, Cansu; Nartas, Eylem Doga; Calibasi-Kocal, Gizem; Akdogan, YasarChloroaluminum phthalocyanine (ClAlPc) loaded bovine serum albumin (BSA) nanoparticles (NPs) were synthesized as a dual-functional platform for photodynamic and sonodynamic therapies (PDT and SDT). ClAlPc loading did not disturb the morphology of the BSA NPs. Their spherical structure, with a size around 200 nm, was preserved upon ClAlPc loading (1 %w/w). Singlet oxygen productions in the presence of ClAlPc loaded BSA NPs or free ClAlPc were determined by ultraviolet absorption (UV-vis) spectroscopy and electron paramagnetic resonance (EPR) spectroscopy. While a slower rate of singlet oxygen formation rate after both PDT and SDT was detected by UV-vis measurements in the presence of ClAlPc loaded BSA NPs, EPR results showed a similar rate of singlet oxygen formation for both ClAlPc loaded BSA NPs and free ClAlPc. Confocal microscopy confirmed the efficient cellular uptake and perinuclear localization of the ClAlPc loaded BSA NPs in HCT-116 cancer cells. In vitro cytotoxicity studies demonstrated a dose and time dependent photo-and sonotoxic effects in the presence of ClAlPc loaded BSA. In particular, simultaneous application of light and ultrasound as sono-photodynamic therapy (SPDT) resulted in 15 % cell viability in the presence of ClAlPc loaded BSA NPs, which is much lower than individual PDT and SDT results, confirming the effect of the combination therapy on cell viability. In comparison, free ClAlPc reduced cell viability to 27 %. These findings suggest that ClAlPc loaded BSA NPs is a promising "one-for-two" nanoplatform for combined cancer therapy to reduce the limitations of both methods.Article Effects of Cultivation Temperature on Protein Production of Selected Spirulina Strains Under Photobioreactor Conditions(Elsevier, 2026) Binkanat, Tahir Burak; Ozkan, AltanSpirulina is cultivated industrially for food supplement applications due to its high protein content and protein quality. This study assessed the influence of cultivation temperature on the productivity of widely accessible, protein-rich Spirulina strains under standardized bubble column photobioreactor conditions, with the goal of identifying strains with consistently high nutritional value across varying temperatures and culture age for outdoor applications. Five strains were first screened for protein content at 30 degrees C, and three with protein contents >60 % dry biomass were selected for cultivation at 25 degrees C, 35 degrees C, and 40 degrees C. Protein content was measured daily to determine variations, and protein quality was assessed at log and stationary growth phases. The metal content was analyzed to assess the toxic heavy metal bioaccumulation potential. At the optimum temperature of 35 degrees C, the strains had similar biomass productivities. However, the protein contents were highly temperature and strain-specific. Based on the strain, under identical process conditions, a relatively stable protein content of around 65 % or a content variation from 30 to 70 % was observed through the cultivation. Growth at 25 degrees C lowered the biomass productivity without affecting the protein contents, and growth at 40 degrees C lowered both parameters. S. platensis UTEX 2340 had consistently the highest protein quality, reflected by its higher cumulative essential amino acid contents and essential amino acid index scores. However, at 35 degrees C, the strain also had a mercury content exceeding the safety limits set for food supplements. These findings demonstrate the importance of strain selection and cultivation temperature in maintaining the nutritional value of Spirulina-based products.Article 3D-Printed Soy Protein and Microalga Films: A Sustainable Approach with Antioxidant Functionality(Elsevier, 2026) Barekat, Sorour; Dogan, Buse; Uzuner, Sibel; Ubeyitogullari, AliThis study investigated the optimization and fabrication of soy protein isolate (SPI)-green microalga (MA) 3D-printed films. For optimizing 3D printing, the effects of MA concentration, nozzle size (0.52-0.81 mm), and speed (10-20 mm/s) were examined. The printed films were then dried, and color, mechanical properties, water vapor permeability, structure, and antioxidant activity were analyzed. All the formulations showed shear-thinning behavior and rapid recovery. The concentration of 3 % MA, nozzle size of 0.72 mm, and printing speed of 20 mm/s were selected as the optimized conditions for the best 3D printability. Compared with the control, their elongation at break decreased by more than 16 %, while puncture strength increased by over 12 %, and tensile strength rose by more than 40 %. Water vapor permeability decreased by more than 40 % with the addition of MA. The microstructure images and secondary structure confirmed the formation of a less porous and stronger gel network with an increase in MA concentration from 0 to 5 % (w/w). The antioxidant properties of SPI films also increased two-fold with the addition of MA. These findings highlight that the 3D-printed edible films with antioxidant properties could be used as an eco-friendly and nutritious alternative to petroleum-based films in food packaging.Article Chain-Length Dependent and Synergistic Prebiotic Effects of Xylooligosaccharides and Xylan on the Fecal Microbiota of Mice in Vitro(Elsevier, 2025) Sabanci, Kevser; Gulec, Sukru; Buyukkileci, Ali OguzOligomeric and polymeric prebiotics differ in their structural complexity, which influences microbial accessibility and fermentation kinetics. This study investigated the microbial responses to xylooligosaccharides (XOS), xylan (XY), and their combinations in comparison with inulin (INU) using an in vitro model inoculated with BALB/c mice fecal microbiota. Temporal analyses over 48 h included substrate consumption, acid production, and changes in microbial diversity. XOS was rapidly fermented, yielding high acetate and lactate levels, whereas XY was utilized more slowly due to its polymeric structure. During XY fermentation, xylobiose (X2) and xylotriose (X3) accumulated transiently, suggesting a stepwise depolymerization and utilization mechanism. The XOS + XY mix showed enhanced prebiotic effect, producing the highest amount of acid (151.8 mmol/L) and notably promoted the simultaneous enrichment of Bifidobacterium (12.5-fold), Bacteroides (8.85-fold), and Lactobacillus (14.9-fold) species compared to individual treatments These findings demonstrate that coadministered XOS and XY highlights the potential for designing tailored prebiotic formulations to optimize microbiota modulation, with potential relevance for human health.Editorial Materials Science and Engineering for Circularity: Challenges, Strategies and Solution(Elsevier, 2026) Beck, Gesa; Balle, Frank; Gokelma, Mertol; Shamsuyeva, Madina; Perotto, Giovanni; Gulia, KiranArticle Citation - WoS: 1Citation - Scopus: 1Incorporating Legume and Nut Flours Into Pasta, Bakery Products, and Snacks: Opportunities and Challenges(Elsevier, 2025) Imeneo, V.; Tokatli, F.; Ozen, B.; Cappa, C.; Aguilo-Aguayo, I.; Alamprese, CristinaLegumes and nuts have recently emerged in pasta, bakery, and snack manufacturing, offering a myriad of health benefits and culinary versatility. Incorporating legume and nut flours in these products can lead to enhanced nutritional profiles, while diversifying the future food offering, and mitigating environmental footprints. However, their integration needs careful consideration of various factors, including sensory properties, structural features, and processing techniques. This review endeavors to provide a comprehensive overview of the current state-of-the-art research about the use of legume and nut flours in pasta, bakery, and snack production, elucidating the opportunities, challenges, and future directions.