WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Polyaspartic Ester Polyurea-TiO2nanocomposite Coatings for UV Protection of Leading Edge of Wind Turbine Blades(Elsevier B.V., 2026) Olcer, Y.A.; Karabacak, B.D.; Demirkurt, M.; Yoldaş, İ.; Can y, Z.; Demir, M.Polyaspartic ester polyurea (PAEPU) supplies a promising matrix for high-durability coatings. However, its poor UV-A resistance make its usage limited. In this work, commercially available anatase TiO<inf>2</inf> particles (0.05–10 wt%) were dispersed in PAE matrix without any modification. PAEPU/TiO<inf>2</inf> composites were supplied by the reaction of PAE/TiO<inf>2</inf> matrix with an aliphatic isocyanate. UV–Visible spectra of spin coated PAEPU/TiO<inf>2</inf> composite thin films showed an exponential decrease in transmittance with increasing amount of TiO<inf>2.</inf> The optical response is dominated by UV blocking for TiO<inf>2</inf> amounts smaller than 0.3 wt%. For above 0.5 wt% TiO<inf>2</inf> amounts, transparency to translucency transition signifies the beginning of multiple scattering. The diameter of particles analyzed by AFM showed that particle diameter is 47 ± 11 nm taking into account of images of the PAEPU films containing 0.3 wt% of TiO<inf>2</inf> particles. Radial distribution function of the particle domains achieved from microscopy suggests that interparticle distance gets smaller than the wavelength of the incident light even at low the particle concentration. Accelerated weathering test were performed by applying 0.1, 0.5, 1.0, and 3.0 wt% TiO<inf>2</inf> containing PAEPU composite films on a white primer with Doctor Blade method. 0.1 wt% PAEPU/TiO<inf>2</inf> composites shows lower ΔE value compare to both neat and higher amounts of TiO<inf>2</inf> containing PAEPU composite films. The results suggest that without the complexity and cost of the surface modification, the low loading of commercial TiO<inf>2</inf> into PAE matrix may supply UV-stabilized PAEPU coatings relevant to the leading-edge protection of wind-turbine blades. © 2025 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.Article A Simplified Molecular Imprinting Strategy Through Electrospinning of Polyacrylonitrile for Thin Film Microextraction of Selected Pesticides(Elsevier B.V., 2026) Şahin, A.; Akpinar, Y.; Yildirim, E.; Eroǧlu, A.E.; Boyaci, E.Molecularly imprinted polymers (MIPs) have been extensively used as selective extractive phases for sample preparation because of their analyte-selective binding sites. However, MIP preparation requires optimized monomer-template interactions and long polymerization reactions. In this study, a novel and simple method of MIP preparation was proposed based on electrospinning. Instead of preparing analyte-monomer complexes before polymerization, model analytes (trifluralin and carbaryl) were directly dissolved in a polyacrylonitrile (PAN) solution, then electrospun into nanofibrous mats. This allowed for a means of preparation of highly crystalline, template-imprinted nanostructures with minimal synthetic complexity. Following the characterization studies for the new material, the extraction properties of the imprinted and nonimprinted electrospun mats were investigated in thin film microextraction (TFME) studies by extracting trifluralin and carbaryl from water samples, followed by gas chromatography-mass spectrometry (GC–MS) analysis. The optimization results showed that samplers containing 10.0 mg of MIP sorbents made by electrospinning of a solution containing 5.0 mg of template in 1.0 mL of PAN solution resulted in approximately 4 and 7 times enhanced extraction recoveries for carbaryl and trifluralin compared to samplers made of non-imprinted bulk PAN. Moreover, the cross-reactivity testing performed with non-template analytes (malathion and diazinon) suggested a more specific extraction towards trifluralin compared to carbaryl. The proposed new technique was also validated using computational methodology, which supported the experimental finding about higher selectivity towards trifluralin. This may signify a probability for structural orientation of partially charged trifluralin under an electrical field in electrospun PAN creating favorable extraction sites. © 2025 Elsevier B.V.Article Citation - WoS: 3Citation - Scopus: 1Porous Polymer-Derived Ceramics for Environmental Applications: Sorption, Filtration, and Catalysis(Elsevier B.V., 2025) Icin, Oyku; Zeydanli, Damla; Biesuz, Mattia; Soraru, Gian Domenico; Vakifahmetoglu, CekdarPolymer-derived ceramics (PDCs), obtained from preceramic polymers, have emerged as promising materials for environmental applications due to their high thermal and chemical stability, tunable nano-microstrucure and porosity, and versatile surface functionalities. This review focuses on the recent advances in porous PDCs and their use in key environmental fields such as sorption, filtration, and catalysis. A comparative analysis of precursor chemistry, synthesis strategies, and resulting structural properties is presented, emphasizing how these factors influence performance in environmental remediation tasks. By consolidating findings across specific application areas, the work aims to clarify the functional potential of PDCs and identify current research gaps and opportunities for future development in environmental material science.Article Citation - WoS: 2Citation - Scopus: 2A Comprehensive Study on the Effectiveness of the Stress and Damage Model Parameters in Predicting the Compression Fracture Behavior of Selective Laser Melted AlSi10Mg BCC Lattices(Elsevier B.V., 2025) Guden, Mustafa; Erten, Hacer Irem; Gorguluarslan, Recep M.; Gulletutan, Umut Can; Dagkolu, Akin; Gokdag, Istemihan; Namazov, SubhanThe Johnson and Cook (JC) stress and damage model parameters determined from the machined bulk cylindrical specimens and as-built struts through tension and compression tests were used to model quasi-static compression behavior of selective laser melt-fabricated AlSi10Mg alloy lattices. The lattices had the same cell size (10 mm) and strut diameter (1 mm), but different number of cells (2 x 2 x 2, 10 x 10 x 2 and 5 x 5 x 5) and geometries (sandwich and cubic). Four different sets of JC damage model parameters (brittle and ductile notch-insensitive and compression and tension notch-sensitive) were further implemented in the lattice compression numerical models. The brittle damage model parameters and smaller mesh sizes resulted in cracking the face-sheet corner strut nodes before the occurrence of a bending-dominated initial peak stress. The notch-sensitive damage model parameters exhibited no bent-strut fracture in the middle layers of the lattices and increased the crack initiation strains as compared with the notch-insensitive damage model parameters. Despite significant variations in the initial peak stresses of the tested 2 x 2 x 2 and 10 x 10 x 2 lattices, the implication of the strut micro-tension stress model together with the compression notch-sensitive damage model parameters using 0.25 mm mesh size conservatively approximated the experimental deformation stresses while the machined bulk specimen tensionstress model over predicted the experimental stresses. On the other side, the strut stress model with 0.15 mm mesh size accurately predicted the experimental diagonal shear/fracture mode of struts with a slightly higher numerical initial peak stress. The compression tests on the strut specimens extracted from the as-built lattices yielded similar stress model parameters with the micro-tension tests. The differences between the initial peak stresses of the investigated sandwich and cubic lattices were further explained by the differences in the lattice boundary conditions.Article Citation - WoS: 24Citation - Scopus: 23Photovoltaic Performance of Magnetron Sputtered Antimony Selenide Thin Film Solar Cells Buffered by Cadmium Sulfide and Cadmium Sulfide /Zinc Sulfide(Elsevier B.V., 2023) Cantas, A.; Gundogan, S.H.; Turkoglu, F.; Koseoglu, H.; Aygun, G.; Ozyuzer, L.Antimony selenide (Sb2Se3)-based thin-film solar cells have recently attracted worldwide attention as an abundant, low-cost, and efficient photovoltaic technology. The highest efficiencies recorded for Sb2Se3 solar cells have been obtained using cadmium sulfide (CdS) as a buffer layer. The Cd-included hybrid buffer layers could be one option to increase device efficiency through more effective usage of light. Therefore, in this work, the effect of single CdS and hybrid CdS/zinc sulfide (ZnS) buffer layers on the photovoltaic performance of Sb2Se3 thin-film solar cells has been investigated in detail. Sb2Se3 thin films have been deposited on molybdenum (Mo)-coated soda-lime glass (SLG) substrates by radio frequency magnetron sputtering technique followed by a post-heat treatment process. The morphological, and structural properties of Sb2Se3 thin films have been investigated by X-Ray Diffraction and Scanning Electron Microscopy. To compare the device performances of single CdS and hybrid CdS/ZnS buffered Sb2Se3 thin-film solar cells, SLG/Mo/Sb2Se3/CdS/ZnS/indium tin oxide (ITO) and SLG/Mo/Sb2Se3/CdS/ITO structures have been fabricated. The findings of this study have revealed a reduction in solar cells’ performance from η=3.93% for CdS buffer to η=0.13% for CdS/ZnS hybrid buffer. The change in the solar cell performance using the CdS/ZnS hybrid buffer has been discussed in detail. © 2023 Elsevier B.V.Article Citation - WoS: 5Citation - Scopus: 9Using Loofah Reinforced Chitosan-Collagen Hydrogel Based Scaffolds In-Vitro and In-Vivo; Healing in Cartilage Tissue Defects(Elsevier B.V., 2023) Baysan, G.; Gunes, O.C.; Turemis, C.; Akokay, Yilmaz, P.; Husemoglu, R.B.; Kara, Ozenler, A.; Perpelek, M.The herein article aims to report a new scaffold design as a loofah-reinforced chitosan-collagen hydrogel composite scaffold with three different cross-linker concentrations (0.1, 0.3, and 0.5 wt. /v%). From the analyses, the scaffold crosslinked with 0.5% genipin; collagen-chitosan hydrogel scaffold reinforced with loofah (L-CCol5) was found to be suitable for further in vitro and in vivo studies due to its interconnected porous structure, water content (∼ 97%) and tan delta (0.221 at 1 Hz) values comparable to that of cartilage tissue. In vitro analyses depicted that the L-CCol5 scaffold supported rabbit mesenchymal stem cells (rMSCs) adhesion and proliferation with its non-cytotoxic feature. Moreover, in vivo cartilage healing studies were performed using New Zealand male rabbits in three groups: empty control, cell-free scaffold, and rMSCs-laden scaffold. The elastic moduli of these three groups were 0.69, 0.90, and 1.18 MPa, respectively. Besides, microcomputer tomography (MicroCT) scannings supported the in vivo biomechanical analyses as cell-laden scaffolds showed better osteochondral healing. It can be concluded that the L-CCol5 scaffold could be a promising construct in osteochondral tissue engineering applications. The findings revealed that osteochondral remodeling precedes articular cartilage, providing insight into tailored therapeutic approaches, disease progress, and treatment consequences. © 2023 Acta Materialia Inc.Article Citation - WoS: 5Citation - Scopus: 7Search for Wγ Resonances in Proton-Proton Collisions at S=13 TeV Using Hadronic Decays of Lorentz-Boosted W Bosons(Elsevier B.V., 2022) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Bergauer, T.; Dragicevic, M.; Erö, J.; Alves, G.A.A search for Wγ resonances in the mass range between 0.7 and 6.0 TeV is presented. The W boson is reconstructed via its hadronic decays, with the final-state products forming a single large-radius jet, owing to a high Lorentz boost of the W boson. The search is based on proton-proton collision data at s=13 TeV, corresponding to an integrated luminosity of 137 fb−1, collected with the CMS detector at the LHC in 2016–2018. The Wγ mass spectrum is parameterized with a smoothly falling background function and examined for the presence of resonance-like signals. No significant excess above the predicted background is observed. Model-specific upper limits at 95% confidence level on the product of the cross section and branching fraction to the Wγ channel are set. Limits for narrow resonances and for resonances with an intrinsic width equal to 5% of their mass, for spin-0 and spin-1 hypotheses, range between 0.17 fb at 6.0 TeV and 55 fb at 0.7 TeV. These are the most restrictive limits to date on the existence of such resonances over a large range of probed masses. In specific heavy scalar (vector) triplet benchmark models, narrow resonances with masses between 0.75 (1.15) and 1.40 (1.36) TeV are excluded for a range of model parameters. Model-independent limits on the product of the cross section, signal acceptance, and branching fraction to the Wγ channel are set for minimum Wγ mass thresholds between 1.5 and 8.0 TeV. © 2022 The Author(s)Article Citation - WoS: 15Citation - Scopus: 17A Novel Search and Survey Technique for Unmanned Aerial Systems in Detecting and Estimating the Area for Wildfires(Elsevier B.V., 2021) Sarkar, M.; Yan, X.; Erol, B.A.; Raptis, I.; Homaifar, A.In recent years Unmanned Aerial Vehicles (UAVs) have progressively been utilized for wildfire management, and are especially in prevalent in forest fire monitoring missions. To ensure the fast detection and accurate area estimation of forest fires, a two-step search and survey algorithm for multi-UAV system is proposed to address these fire scenarios. Initially, a grid-based partition method is applied to divide the area-of-interest into several search areas. Then, an archetype search pattern is used to provide timely UAV exploration within those sub-areas. Once the fire zones are detected, a novel survey strategy is employed for UAVs to discover the boundary points of the fire zones, so that the area of the fire zones can be estimated using the sampled boundary points. In addition, the effect of wind is accounted for improving fire zone boundary estimates. The proposed search-and-survey procedure is validated on multiple simulated scenarios using the U.S. Air Force's mission-realistic Aerospace Multi-Agent Simulation Environment (AMASE) software. Simulation results showcase that the proposed search pattern can effectively discover the seeded fire zones within 40 min of the mission. This is relatively faster than the other two well-known search patterns. Moreover, the proposed survey technique provides a coverage estimate with at least 85% accuracy for the area of interest within 90 min of the mission. © 2021 Elsevier B.V.Article Citation - WoS: 15Citation - Scopus: 19Study of J/Ψ Meson Production Inside Jets in pp Collisions at S=8 TeV(Elsevier B.V., 2020) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Bergauer, T.; Brandstetter, J.; Hensel, C.A study of the production of prompt J/ψ mesons contained in jets in proton-proton collisions at s=8TeV is presented. The analysis is based on data corresponding to an integrated luminosity of 19.1 fb−1 collected with the CMS detector at the LHC. For events with at least one observed jet, the angular separation between the J/ψ meson and the jet is used to test whether the J/ψ meson is part of the jet. The analysis shows that most prompt J/ψ mesons having energy above 15 GeV and rapidity |y|<1 are contained in jets with pseudorapidity |η<inf>jet</inf>|<1. The differential distributions of the probability to have a J/ψ meson contained in a jet as a function of jet energy for a fixed J/ψ energy fraction are compared to a theoretical model using the fragmenting jet function approach. The data agree best with fragmenting jet function calculations that use a long-distance matrix element parameter set in which prompt J/ψ mesons are predicted to be unpolarized. This technique demonstrates a new way to test predictions for prompt J/ψ production using nonrelativistic quantum chromodynamics. © 2020 Elsevier B.V.Article Citation - WoS: 26Citation - Scopus: 27Measurement of the Azimuthal Anisotropy of [Formula Presented] and [Formula Presented] Mesons in PbPb Collisions at S NN =5.02 TeV(Elsevier B.V., 2021) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Bergauer, T.; Dragicevic, M.; De Jesus Damiao, D.The second-order Fourier coefficients (v<inf>2</inf>) characterizing the azimuthal distributions of [Formula presented] and [Formula presented] mesons produced in PbPb collisions at s<inf> <inf>NN</inf> </inf>=5.02TeV are studied. The [Formula presented] mesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The collected data set corresponds to an integrated luminosity of 1.7nb−1. The scalar product method is used to extract the v<inf>2</inf> coefficients of the azimuthal distributions. Results are reported for the rapidity range |y|<2.4, in the transverse momentum interval 0<p<inf>T</inf><50GeV/c, and in three centrality ranges of 10–30%, 30–50% and 50–90%. In contrast to the J/ψ mesons, the measured v<inf>2</inf> values for the [Formula presented] mesons are found to be consistent with zero. © 2021 The Author(s)