Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395

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  • Article
    Seismic Site Classification via Vs30 and SPT-N Values in Antakya City, Türkiye
    (Taylor & Francis Ltd, 2026-01-22) Alosman, Salama Omar; Akin, Muge K.; Cabalar, Ali Firat
    The paper presents an assessment for the seismic site classification (SSC) in Antakya city located in southern central T & uuml;rkiye, strongly affected by three destructive earthquakes of 7.7 Mw took place in Pazarcik (Kahramanmaras) on February 6, 2023, 7.6 Mw took place in Elbistan (Kahramanmaras) on February 6, 2023, and 6.4 Mw took place in Defne (Hatay) on February 20, 2023. The V-S30 and SPT-N values have been used to identify the SSC in the region with respect to the provisions recommended by the National Earthquake Hazards Reduction Program (NEHRP), Design of Structures for Earthquake Resistance (Eurocode 8), and Turkish Building Earthquake Code (TBEC). The values of SPT-N were recorded from the field works that include 630 boreholes in the top 30 m, whilst the V-S30 was calculated through the multichannel analysis of surface waves (MASW) method performed at 977 different locations across the region. The results showed that approximately 51% and 44% of soils in the city of Antakya has been classified as Class C and Class D, respectively, in accordance with the NEHRP and TBEC, whilst 52% and 44% of the same region has been classified as Class B and Class C, respectively, in accordance with the Eurocode 8. Furthermore, a newly proposed correlation as well as already available ones between the V-S30 and SPT-N values have been presented comparatively by an extensive series of GIS maps produced in order to have a much clear understanding on the various soil types in Antakya. Evidently, the results of this research should be of a great significance for researchers and practitioners working on the earthquake-resistant structures, prediction of ground movements, and in seismic risk assessments.
  • Article
    G-C3N4@Fe3O4 Nanomaterial Synthesis for Magnetic Solid-Phase Extraction and Photocatalytic Removal of Basic Blue 3
    (Springer Heidelberg, 2025-12-16) Kizil, Nebiye; Kayaci, Nilgun; Erbilgin, Duygu Erkmen; Yola, Mehmet Lutfi; Yilmaz, Erkan; Soylak, Mustafa
    The present research synthesized a g-C3N4@Fe3O4 hybrid material for efficient magnetic solid-phase extraction (MSPE) and photocatalytic degradation of Basic Blue 3 (BB3) dye from wastewater. Characterization of the synthesized g-C3N4@Fe3O4 was conducted through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The optimization of the method was carried out by examining parameters such as pH, g-C3N4@Fe3O4 amount, sample volume, and adsorption/desorption duration. In addition, analytical performance criteria such as limit of detection (LOD), limit of quantification (LOQ), and relative standard deviation (RSD) of the MSPE method were calculated as 1.29 mu g L-1, 4.28 mu g L-1, and 1.9%, respectively. The method was applied to real samples, including wastewater and textiles, and validated through addition/recovery studies for the magnetic solid-phase extraction procedure. The recoveries were gained between 91 and 100%. The reusability synthesized g-C3N4@Fe3O4 was also evaluated. The recoveries for Basic Blue 3 dye decreased to 81% after the fourth experiment. Furthermore, the photocatalytic performance of the g-C3N4@Fe3O4 hybrid material was evaluated due to its good surface area and strong interaction with Basic Blue 3 dye. The photocatalytic activity of g-C3N4@Fe3O4 hybrid material was calculated as 96.8% for 100 mg in 300 min.
  • Article
    Does Your Love Lift Me Higher? A Direct Replication of the Energising Role of Secure Relationships
    (John Wiley & Sons Ltd, 2025-12-07) Lagap, Adar Cem; Harma, Mehmet
    Previous work has revealed that priming people with significant others increases feelings of security and energy, and in turn, boosts exploration motivations. In this preregistered study, we directly replicated Luke et al.'s (2012) Study 2 (N = 281). We found similar results as the replicated study regarding increased security feelings and exploration motivations on the self-report measures after the priming. However, we did not find any support for the increased energy feelings after the attachment security priming. In addition, contrary to Luke et al.'s (2012) results, energy feelings did not mediate the relationship between security priming and exploration motivations. A discussion of null findings, along with the limitations of self-reports and potential misinterpretation of the mediational analyses, follows. We also discuss possible future implications of the current findings.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 1
    Fully Inorganic Colloidal CsPbBr3 Perovskite Nanocrystals with Zn-Doping and Metal Oxide Encapsulation for Luminescent Display Panels
    (Amer Chemical Soc, 2025-11-07) Khorasani, Azam; Soheyli, Ehsan; Mutlugun, Evren
    Perovskite nanocrystals (PeNCs) are emerging as exceptional materials due to their high photoluminescence quantum yield, tunable bandgap, and excellent charge carrier mobility, enabling a wide range of colors and promising applications in optoelectronics and photovoltaics. Despite their advantages, PeNCs face stability challenges caused by environmental factors. In the presented study, a facile and versatile colloidal hot-injection method was used to apply the beneficial aspects of Zn-doping in cesium lead bromide (CsPbBr3) PeNCs. The uniform platelet-shaped Zn-doped CsPbBr3 PeNCs were prepared by doping with a 0.1 molar ratio of zinc-oleate solution in the perovskite precursors during synthesis. Then, zinc-oxide (ZnO) and nickel-oxide (NiO) coating layers were utilized separately to effectively reduce surface defects, encapsulate PeNCs, and improve their stability issues. To fabricate the coated PeNCs with metal oxides, zinc acetate and nickel(II) acetate tetrahydrate solutions were prepared individually and added to the crude perovskite solutions. The quantum yield of Zn-doped CsPbBr3 (CsPb1-xZnxBr3) PeNCs coated with ZnO increased from 50% for bare CsPbBr3 to over 84%, while NiO-coated PeNCs exhibited a higher yield of 90% both of which remarkably enhanced the emission stability. Moreover, NiO coatings represented a proper protection against surface imperfections and improved resistance to external stimuli. The combination of facile/effective preparation method, excellent emission efficiency, and reliable emission stability nominates the prepared colloidal composite for display pixels, detectors, and lasers.
  • Article
    Citation - WoS: 1
    A Comprehensive Analysis of Acoustic Emission Signals To Distinguish the Different Damage Types for Fiber-Reinforced Polymers: A Review
    (Wiley, 2025-12-03) Yilmaz, Cagatay
    Fiber-reinforced polymers (FRP) attract the attention of key industries, such as aerospace, wind energy, and automotive, as they can reduce the weight of structural components without compromising their mechanical properties. Due to FRP's anisotropic and non-homogeneous structure, their failure under different loading conditions and the corresponding failure mechanisms must be investigated. One method that progressively monitors the failure of FRP underload is Acoustic Emission (AE). AE can register the elastic stress waves in the form of digitized waveforms, released by the discontinuous events that occur in the FRP under load. These discontinuities can be clustered and identified as transverse cracking, fiber/matrix interface debonding, delamination, and fiber failure by analyzing the AE waveforms. Recently, numerous clustering approaches using machine learning algorithms, along with the varying features of AE waveforms, have been developed and are being used. These algorithms include supervised and unsupervised clustering, deep learning algorithms, and neural network methods, among others. While supervised algorithms require a training dataset to classify AE signals, unsupervised algorithms can perform clustering without training datasets. Deep learning and neural network algorithms can train themselves to cluster data, but they may require a significant amount of computer power when the dataset is large. This review paper provides comprehensive information on the clustering algorithm, along with the AE wave features, the range of features for different damage types, and the type of reinforcer.
  • Article
    Enhanced Photoluminescence via Plasmonic Gold Nanoparticles and Improved Stability of Perovskite Nanocrystals in Macroporous (Polydimethylsiloxane) PDMS Matrices
    (Springer, 2025-10-09) Ocal, Sema Karabel; Tiras, Kevser Sahin; Onses, M. Serdar; Mutlugun, Evren
    In this work, we report a simple and cost-effective method for improving both the environmental stability and photoluminescence quantum efficiency (PLQY) of perovskite nanocrystals (PNCs). Through their embedding in a specially designed macroporous polydimethylsiloxane (MPDMS) matrix and incorporation of plasmonic gold nanoparticles (Au NPs), remarkable improvements are achieved. The resulting MPDMS@PNC composites are seen to retain near-unity quantum efficiency even after 24-h immersion in water and are observed to retain over 85% of the original efficiency even at 75 degrees C, displaying excellent thermal stability. More interestingly, by incorporating Au NPs and subjecting the material to mechanical pressure, the lifetime of the PNCs gets further increased. This is due to the more intimate spatial arrangement of Au NPs in the porous matrix, enhancing localized surface plasmon resonance (LSPR) coupling and thereby enhancing the photoluminescence (PL) of the PNCs. In general, this approach offers a scalable and robust route to designing stable, high-performance perovskite-based materials for next-generation optoelectronic applications.
  • Article
    Burg-Aided 2D MIMO Array Extrapolation for Improved Spatial Resolution
    (MDPI, 2025-10-12) Bekar, Muge; Bekar, Ali; Pirkani, Anum; Baker, Christopher John; Gashinova, Marina
    In this paper, the extrapolation of a 2D multiple-input multiple-output (MIMO) array is proposed using the Burg algorithm to achieve higher angular resolution beyond that of the corresponding 2D MIMO virtual array. The main advantage of such an approach is that it allows us to dramatically decrease both the physical size and the number of antenna elements of the MIMO array. The performance and limitations of the Burg algorithm are examined through both simulation and experimentation at 77 GHz. The experimental methodology used to acquire 3D data of range, azimuth and elevation information with the 1D MIMO off-the-shelf radar is described. Using this method, the performance of the proposed array can be tested experimentally, especially at frequencies where it is desired to assess the antenna response prior to fabricating the antenna.
  • Article
    Citation - WoS: 38
    Citation - Scopus: 38
    pH- and Temperature-Responsive Amphiphilic Diblock Copolymers of 4-Vinylpyridine and Oligoethyleneglycol Methacrylate Synthesized by RAFT Polymerization
    (Elsevier Sci Ltd, 2014-01) Topuzogullari, Murat; Bulmus, Volga; Dalgakiran, Eray; Dincer, Sevil
    Diblock copolymers of 4-vinylpyridine (4VP) and oligoethyleneglycol methyl ether methacrylate (OEGMA) were synthesized for the first time using RAFT polymerization technique as potential drug delivery systems. Effects of the number of ethylene glycol units in OEGMA, chain length of hydrophobic P4VP block, pH, concentration and temperature on the solution behavior of the copolymers were investigated comprehensively. Copolymer chains formed micelles at pH values higher than 5 whereas unimeric polymers were observed to exist below pH 5, owing to the repulsion between positively charged P4VP blocks. The size of the micelles was dependent on the relative length of blocks, P4VP and POEGMA. Thermo-responsive properties of copolymers were investigated depending on the pH and length of P4VP block. The increase in the length of P4VP block decreased the LCST substantially at pH 7. At pH 3, LCST of copolymers shifted to higher temperatures due to the increased interaction of copolymers with water through positively charged P4VP block. (C) 2013 Elsevier Ltd. All rights reserved.
  • Article
    Zinc Chalcogenide Based Shell Layers for Colloidal Quantum Wells
    (Wiley, 2025-04-27) Aldemir, Cagatay Han; Yazici, Ahmet Faruk; Ergezer, Nehir; Korkmaz, Taha Can; Mutlugun, Evren; Kelestemur, Yusuf
    Colloidal quantum wells, also known as colloidal nanoplatelets (NPLs), have emerged as a promising class of materials for light-emitting devices (LEDs). However, the most widely studied core/shell NPLs, which rely on cadmium-based shell layers, face challenges due to toxicity concerns and improper charge confinement. To address these limitations, a new synthetic approach is presented that enables the controlled growth of zinc chalcogenide-based shell layers on NPLs. The synthesized CdSe/ZnSe core/shell NPLs exhibit emission between 615 and 630 nm, with a moderate photoluminescence quantum yield (PL-QY) of 40-50%. It is also demonstrated that the lateral dimensions of the CdSe core NPLs significantly affect the optical properties of the core/shell heterostructures, with smaller lateral dimensions resulting in narrower emission linewidths as low as 20 nm. Further passivation of these core/shell NPLs with an additional ZnS shell layer significantly increases the PL-QY up to 80-90%. Finally, the device performance of these two core/shell NPLs is investigated by fabricating solution-processed LEDs. With LEDs incorporating CdSe/ZnSe/ZnS core/multi-shell NPLs as the active light-emitting layer, an external quantum efficiency (EQE) of 3.82% and a maximum brightness of 6477 cd m-2 is obtained. These findings underscore the significant potential of zinc chalcogenide-based shell layers in advancing colloidal NPLs toward high-performance light-emitting devices.
  • Article
    Citation - WoS: 24
    Citation - Scopus: 26
    Wireless Measurement of Elastic and Plastic Deformation by a Metamaterial-Based Sensor
    (MDPI, 2014-10-20) Ozbey, Burak; Demir, Hilmi Volkan; Kurc, Ozgur; Erturk, Vakur B.; Altintas, Ayhan
    We report remote strain and displacement measurement during elastic and plastic deformation using a metamaterial-based wireless and passive sensor. The sensor is made of a comb-like nested split ring resonator (NSRR) probe operating in the near-field of an antenna, which functions as both the transmitter and the receiver. The NSRR probe is fixed on a standard steel reinforcing bar (rebar), and its frequency response is monitored telemetrically by a network analyzer connected to the antenna across the whole stress-strain curve. This wireless measurement includes both the elastic and plastic region deformation together for the first time, where wired technologies, like strain gauges, typically fail to capture. The experiments are further repeated in the presence of a concrete block between the antenna and the probe, and it is shown that the sensing system is capable of functioning through the concrete. The comparison of the wireless sensor measurement with those undertaken using strain gauges and extensometers reveals that the sensor is able to measure both the average strain and the relative displacement on the rebar as a result of the applied force in a considerably accurate way. The performance of the sensor is tested for different types of misalignments that can possibly occur due to the acting force. These results indicate that the metamaterial-based sensor holds great promise for its accurate, robust and wireless measurement of the elastic and plastic deformation of a rebar, providing beneficial information for remote structural health monitoring and post-earthquake damage assessment.