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Why Disadvantaged Primary School Students in Rural Areas Have Lower Reading Skills? A Critical Assessment
(Routledge Journals, Taylor & Francis Ltd, 2025) Kiziltas, Yusuf; Kultas, Emrah
Inequalities between T & uuml;rkiye's geographical regions are significant. It is an important fact that students continuing their education in rural areas in eastern T & uuml;rkiye face many challenges compared to their peers in urban centers. The geography of rural areas can hurt students in several ways, particularly in terms of reading skills. The low reading skills of students in rural areas have been a serious problem in eastern T & uuml;rkiye for many years. National and international exam results also show that reading skills are lower in rural areas. In this study, the reasons for the low reading skills of primary school students in rural areas were critically examined through a literature review. The discussions include approaches such as the Matthew effect, spatial justice theory, and faucet theory. According to critical evaluations, the reasons for the low reading skills of disadvantaged primary school students in rural areas in eastern T & uuml;rkiye are pretty diverse. The socioeconomic levels of families, inequalities in opportunities and resources, school closures, negative factors related to location and geography, linguistic differences, problems with teaching materials, temporary teaching arrangements, and low levels of parental involvement are at the forefront.
Multimodal Prediction of Pathological Complete Response in Esophageal Cancer Using Automated Machine Learning and Variational Autoencoder-Based Synthetic Data Augmentation
(Amer Assoc Cancer Research, 2025) Dincer, Sefika; Tugrul, Taylan; Kara, Mahmut; Aldemir, Mehmet Naci
Mixed Hydrogenetic-Hydrothermal Genesis of Quaternary Ferromanganese Nodules in a Tectonically Active Lacustrine Basin, Eastern Türkiye
(Pergamon-Elsevier Science Ltd, 2025) Uner, Tijen
This study presents a detailed investigation of the mineralogical, geochemical, and rare earth element (REE) characteristics of ferromanganese nodules found within Quaternary lacustrine sediments in the Agri region of Eastern Anatolia, T & uuml;rkiye. These nodules, primarily composed of goethite and manganite with minor quartz, exhibit botryoidal and colloform textures typical of low-temperature diagenetic environments. Raman and XRD analyses identified significant iron and manganese mineral phases, while SEM-EDX revealed trace amounts of Co, Ni, and Zn associated with these phases. Chondrite-normalized REE patterns demonstrate light REE enrichment, a weak negative europium anomaly (EuN/Eu* = 0.69-0.84), and variable cerium anomalies (CeN/Ce* ranging from 0.74 to 1.95, corresponding to both weak negative and positive Ce anomalies), indicating a mixed hydrogenous and hydrothermal origin under fluctuating redox conditions. These geochemical signatures, together with sedimentological evidence, suggest formation within a restricted lacustrine environment characterized by episodic anoxia and limited detrital input. The results contribute to a broader understanding of Fe-Mn mineralization in continental settings and underscore the influence of volcanic and tectonic processes on nodule genesis.
Dose Enhancement Effects of Different-Sized Nanoparticles on Tumors and Surrounding Tissues Using Geant4 Track Structure Simulation
(Sciendo, 2025) Tugrul, Taylan
Free radicals, which are the most important contributors to cell death in radiotherapy, appear to increase in the presence of nanoparticles. The nanoparticles can be localized within tumor tissues, providing enhanced protection to normal tissues during radiation therapy while achieving significant dose enhancement within tumors. In our study, the dose effects of different sizes of spherical gold nanoparticles were analyzed in the tumor environment and surrounding tissues under photon radiation at various energies with the track structure code using the TOPAS interface. The nano-lattice method was used to create an environment similar to the diffusion-based distribution of nanoparticles in the medium. The Geant4-DNA code was utilized for simulations conducted in this study. Although the interaction cross-section is lower at MeV photon energy levels, the results still indicate an increase in dose due to the presence of nanoparticles (NPs) in the medium. As the size of gold nanoparticles increases, the spread in dose enhancements becomes more apparent. The lowest average dose enhancement factor (DEF) values at lateral points were observed for 28.4 nm NPs at MeV photon energy. In this study, the contribution of gold nanoparticles to dose enhancement was investigated using the Monte Carlo track structure algorithm. Additionally, the potential dose variations in the surrounding tissue resulting from the introduction of gold nanoparticles were analyzed. Even though an increase in DEF values was observed at MeV energy levels, these values might vary with a better understanding of biological effects such as cell cycle disruption, oxidative stress, and impaired DNA repair. This study offers valuable insights into nanoparticle-assisted radiation applications, including optimal nanoparticle size and applicable energy levels. By enhancing our understanding of the effects on tissues beyond the tumor and within the surrounding environment, it aims to provide critical information for researchers in the field and make a meaningful contribution to the literature.
Synthesis and Characterisation of Pd/MIL68(Al) Nanoparticles for High Performance Catalytic Reduction of 4-Nitrophenol
(Springer, 2025) Ruzgar, Adem
The discharge of 4-nitrophenol, one of the most significant, widespread, and hazardous organic pollutants found in industrial wastewater, into clean water resources without undergoing adequate and necessary treatment/conversion processes has become a multidimensional issue that threatens all aquatic life. In this study, the reduction of 4-nitrophenol to 4-aminophenol using an efficient, environmentally friendly, and sustainable method was targeted. For this purpose, Pd/MIL68(Al) catalyst was prepared with 2% metal loading using a simple and conventional wet impregnation method. MIL68(Al), an MOF recently attracting attention due to its superior properties, was synthesised using an efficient and environmentally friendly method as support material in the first step of nanocatalyst synthesis. The prepared Pd/MIL68(Al) catalyst was tested in the reaction of the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4 by considering different parameters. In the study where the structure and surface morphology of the Pd/MIL68(Al) catalyst were elucidated using characterisation techniques such as ICP-OES, XRD, SEM, SEM/EDX, TEM, FTIR and XPS, it was determined that Pd(0) nanoparticles were well dispersed on the MIL68(Al) support, with an average particle size of 3.25 +/- 0.22 nm. As a result of the interpretation of the data obtained from the study, the TOFinitial value for 4-NP was determined as 43.42 min-1. In the studies carried out to determine the reusability rate of Pd/MIL68(Al) nanocatalyst, it was determined that Pd/MIL68(Al) nanocatalyst exhibited excellent catalytic efficiency and stability (92%) even after five catalytic cycles. Both the simple preparation process, catalytic efficiency, and high reusability rate of the Pd/MIL68(Al) nanocatalyst are the grounds for the evaluation of Pd/MIL68(Al) nanocatalyst as an important alternative for the reduction of 4-nitrophenol and wastewater treatment.
Citation - Scopus: 1
Hydrothermal Liquefaction of Sinapis Arvensis Biomass Using TiO2-Supported Metal Catalysts: A Study on Bio-Oil Yield and Composition
(Elsevier, 2026) Durak, Halil; Genel, Salih; Genel, Yasar
The development of catalytic systems for hydrothermal liquefaction (HTL) is crucial for transforming lignocellulosic biomass into biofuels with high energy density. This research investigates the HTL process of Sinapis arvensis biomass using TiO2-supported catalysts, specifically Fe, Al, and Fe-Al, at temperatures from 275-325 degrees C. The catalysts were synthesized through incipient wetness impregnation and characterized using techniques like X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and inductively coupled plasma optical emission spectrometry (ICP-OES) to evaluate element distribution and surface chemistry. Findings show that the Al/TiO2 catalyst boosted lighter bio-oil production via acid-catalyzed dehydration and decarboxylation, while the Fe/TiO2 catalyst favored heavier oils through redox-assisted depolymerization. The Fe-Al/TiO2 bifunctional catalyst exhibited superior biomass conversion, yielding more aliphatic hydrocarbons. Gas chromatography-mass spectrometry (GC-MS) revealed how catalysts influenced product distributions, increasing monoaromatic and aliphatic compounds and reducing oxygenated entities. Elemental analysis confirmed higher carbon content, lower oxygen levels, and improved higher heating values (HHVs) in catalyzed bio-oils, indicating enhanced fuel quality.
Effect of Geometry and Fiber Type on Energy Absorption in Polymer Based Composite Crash Boxes: An Experimental Study
(Wiley, 2025) Kosedag, Ertan; Araz, Zumray; Erkek, Baran
Vehicle crash boxes, mounted on the chassis before the bumper, absorb impact energy to protect passengers, but their metal construction adds weight, prompting increased research into lightweight composite alternatives with comparable strength. In this study, energy absorption values (EA), specific energy absorption (SEA), peak forces (PF) and crashing force efficiency (CFE) of carbon fiber, glass fiber, and aramid fiber reinforced composite crash boxes with epoxy resin matrix were compared. Composite crash boxes with different geometries were fabricated using vacuum infusion method in three different geometries: hexagonal, circle, and square. Unlike hand lay-up and prepreg winding methods, vacuum infusion method was chosen because it provides homogeneous distribution of epoxy resin. The crashworthiness of the samples was evaluated through quasi-static compression tests. The best energy absorption performance was obtained with the hexagonal carbon fiber-reinforced composite crash box (246.17 J), corresponding to a specific energy absorption of 8.57 J/g. Although aramid fiber-reinforced specimens showed lower energy absorption, they exhibited the highest crash force efficiency among all tested configurations. These results confirm the significant influence of both fiber type and geometry on the crashworthiness of polymer-based composite crash boxes. The study highlights that hexagonal geometry consistently provided superior energy absorption across all fiber types, while carbon fiber-reinforced composites demonstrated the best overall mechanical performance, making them strong candidates for lightweight crashworthiness applications.
Mixed Hydrogenetic-Hydrothermal Genesis of Quaternary Ferromanganese Nodules in a Tectonically Active Lacustrine Basin, Eastern Türkiye
(Pergamon-Elsevier Science Ltd, 2025) Uner, Tijen
This study presents a detailed investigation of the mineralogical, geochemical, and rare earth element (REE) characteristics of ferromanganese nodules found within Quaternary lacustrine sediments in the Agri region of Eastern Anatolia, T & uuml;rkiye. These nodules, primarily composed of goethite and manganite with minor quartz, exhibit botryoidal and colloform textures typical of low-temperature diagenetic environments. Raman and XRD analyses identified significant iron and manganese mineral phases, while SEM-EDX revealed trace amounts of Co, Ni, and Zn associated with these phases. Chondrite-normalized REE patterns demonstrate light REE enrichment, a weak negative europium anomaly (EuN/Eu* = 0.69-0.84), and variable cerium anomalies (CeN/Ce* ranging from 0.74 to 1.95, corresponding to both weak negative and positive Ce anomalies), indicating a mixed hydrogenous and hydrothermal origin under fluctuating redox conditions. These geochemical signatures, together with sedimentological evidence, suggest formation within a restricted lacustrine environment characterized by episodic anoxia and limited detrital input. The results contribute to a broader understanding of Fe-Mn mineralization in continental settings and underscore the influence of volcanic and tectonic processes on nodule genesis.
Multimodal Prediction of Pathological Complete Response in Esophageal Cancer Using Automated Machine Learning and Variational Autoencoder-Based Synthetic Data Augmentation
(Amer Assoc Cancer Research, 2025) Dincer, Sefika; Tugrul, Taylan; Kara, Mahmut; Aldemir, Mehmet Naci
Why Disadvantaged Primary School Students in Rural Areas Have Lower Reading Skills? A Critical Assessment
(Routledge Journals, Taylor & Francis Ltd, 2025) Kiziltas, Yusuf; Kultas, Emrah
Inequalities between T & uuml;rkiye's geographical regions are significant. It is an important fact that students continuing their education in rural areas in eastern T & uuml;rkiye face many challenges compared to their peers in urban centers. The geography of rural areas can hurt students in several ways, particularly in terms of reading skills. The low reading skills of students in rural areas have been a serious problem in eastern T & uuml;rkiye for many years. National and international exam results also show that reading skills are lower in rural areas. In this study, the reasons for the low reading skills of primary school students in rural areas were critically examined through a literature review. The discussions include approaches such as the Matthew effect, spatial justice theory, and faucet theory. According to critical evaluations, the reasons for the low reading skills of disadvantaged primary school students in rural areas in eastern T & uuml;rkiye are pretty diverse. The socioeconomic levels of families, inequalities in opportunities and resources, school closures, negative factors related to location and geography, linguistic differences, problems with teaching materials, temporary teaching arrangements, and low levels of parental involvement are at the forefront.
Synthesis and Characterisation of Pd/MIL68(Al) Nanoparticles for High Performance Catalytic Reduction of 4-Nitrophenol
(Springer, 2025) Ruzgar, Adem
The discharge of 4-nitrophenol, one of the most significant, widespread, and hazardous organic pollutants found in industrial wastewater, into clean water resources without undergoing adequate and necessary treatment/conversion processes has become a multidimensional issue that threatens all aquatic life. In this study, the reduction of 4-nitrophenol to 4-aminophenol using an efficient, environmentally friendly, and sustainable method was targeted. For this purpose, Pd/MIL68(Al) catalyst was prepared with 2% metal loading using a simple and conventional wet impregnation method. MIL68(Al), an MOF recently attracting attention due to its superior properties, was synthesised using an efficient and environmentally friendly method as support material in the first step of nanocatalyst synthesis. The prepared Pd/MIL68(Al) catalyst was tested in the reaction of the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4 by considering different parameters. In the study where the structure and surface morphology of the Pd/MIL68(Al) catalyst were elucidated using characterisation techniques such as ICP-OES, XRD, SEM, SEM/EDX, TEM, FTIR and XPS, it was determined that Pd(0) nanoparticles were well dispersed on the MIL68(Al) support, with an average particle size of 3.25 +/- 0.22 nm. As a result of the interpretation of the data obtained from the study, the TOFinitial value for 4-NP was determined as 43.42 min-1. In the studies carried out to determine the reusability rate of Pd/MIL68(Al) nanocatalyst, it was determined that Pd/MIL68(Al) nanocatalyst exhibited excellent catalytic efficiency and stability (92%) even after five catalytic cycles. Both the simple preparation process, catalytic efficiency, and high reusability rate of the Pd/MIL68(Al) nanocatalyst are the grounds for the evaluation of Pd/MIL68(Al) nanocatalyst as an important alternative for the reduction of 4-nitrophenol and wastewater treatment.
Dose Enhancement Effects of Different-Sized Nanoparticles on Tumors and Surrounding Tissues Using Geant4 Track Structure Simulation
(Sciendo, 2025) Tugrul, Taylan
Free radicals, which are the most important contributors to cell death in radiotherapy, appear to increase in the presence of nanoparticles. The nanoparticles can be localized within tumor tissues, providing enhanced protection to normal tissues during radiation therapy while achieving significant dose enhancement within tumors. In our study, the dose effects of different sizes of spherical gold nanoparticles were analyzed in the tumor environment and surrounding tissues under photon radiation at various energies with the track structure code using the TOPAS interface. The nano-lattice method was used to create an environment similar to the diffusion-based distribution of nanoparticles in the medium. The Geant4-DNA code was utilized for simulations conducted in this study. Although the interaction cross-section is lower at MeV photon energy levels, the results still indicate an increase in dose due to the presence of nanoparticles (NPs) in the medium. As the size of gold nanoparticles increases, the spread in dose enhancements becomes more apparent. The lowest average dose enhancement factor (DEF) values at lateral points were observed for 28.4 nm NPs at MeV photon energy. In this study, the contribution of gold nanoparticles to dose enhancement was investigated using the Monte Carlo track structure algorithm. Additionally, the potential dose variations in the surrounding tissue resulting from the introduction of gold nanoparticles were analyzed. Even though an increase in DEF values was observed at MeV energy levels, these values might vary with a better understanding of biological effects such as cell cycle disruption, oxidative stress, and impaired DNA repair. This study offers valuable insights into nanoparticle-assisted radiation applications, including optimal nanoparticle size and applicable energy levels. By enhancing our understanding of the effects on tissues beyond the tumor and within the surrounding environment, it aims to provide critical information for researchers in the field and make a meaningful contribution to the literature.
Citation - Scopus: 1
Hydrothermal Liquefaction of Sinapis Arvensis Biomass Using TiO2-Supported Metal Catalysts: A Study on Bio-Oil Yield and Composition
(Elsevier, 2026) Durak, Halil; Genel, Salih; Genel, Yasar
The development of catalytic systems for hydrothermal liquefaction (HTL) is crucial for transforming lignocellulosic biomass into biofuels with high energy density. This research investigates the HTL process of Sinapis arvensis biomass using TiO2-supported catalysts, specifically Fe, Al, and Fe-Al, at temperatures from 275-325 degrees C. The catalysts were synthesized through incipient wetness impregnation and characterized using techniques like X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and inductively coupled plasma optical emission spectrometry (ICP-OES) to evaluate element distribution and surface chemistry. Findings show that the Al/TiO2 catalyst boosted lighter bio-oil production via acid-catalyzed dehydration and decarboxylation, while the Fe/TiO2 catalyst favored heavier oils through redox-assisted depolymerization. The Fe-Al/TiO2 bifunctional catalyst exhibited superior biomass conversion, yielding more aliphatic hydrocarbons. Gas chromatography-mass spectrometry (GC-MS) revealed how catalysts influenced product distributions, increasing monoaromatic and aliphatic compounds and reducing oxygenated entities. Elemental analysis confirmed higher carbon content, lower oxygen levels, and improved higher heating values (HHVs) in catalyzed bio-oils, indicating enhanced fuel quality.
Effect of Geometry and Fiber Type on Energy Absorption in Polymer Based Composite Crash Boxes: An Experimental Study
(Wiley, 2025) Kosedag, Ertan; Araz, Zumray; Erkek, Baran
Vehicle crash boxes, mounted on the chassis before the bumper, absorb impact energy to protect passengers, but their metal construction adds weight, prompting increased research into lightweight composite alternatives with comparable strength. In this study, energy absorption values (EA), specific energy absorption (SEA), peak forces (PF) and crashing force efficiency (CFE) of carbon fiber, glass fiber, and aramid fiber reinforced composite crash boxes with epoxy resin matrix were compared. Composite crash boxes with different geometries were fabricated using vacuum infusion method in three different geometries: hexagonal, circle, and square. Unlike hand lay-up and prepreg winding methods, vacuum infusion method was chosen because it provides homogeneous distribution of epoxy resin. The crashworthiness of the samples was evaluated through quasi-static compression tests. The best energy absorption performance was obtained with the hexagonal carbon fiber-reinforced composite crash box (246.17 J), corresponding to a specific energy absorption of 8.57 J/g. Although aramid fiber-reinforced specimens showed lower energy absorption, they exhibited the highest crash force efficiency among all tested configurations. These results confirm the significant influence of both fiber type and geometry on the crashworthiness of polymer-based composite crash boxes. The study highlights that hexagonal geometry consistently provided superior energy absorption across all fiber types, while carbon fiber-reinforced composites demonstrated the best overall mechanical performance, making them strong candidates for lightweight crashworthiness applications.
Citation - WoS: 10
Citation - Scopus: 11
An update on molecular biology and drug resistance mechanisms of multiple myeloma
(Elsevier Science inc, 2015) Mutlu, Pelin; Kiraz, Yagmur; Gunduz, Ufuk; Baran, Yusuf; Baran, Yusuf
Multiple myeloma (MM), a neoplasm of plasma cells, is the second most common hematological malignancy. Incidance rates increase after age 40. MM is most commonly seen in men and African-American population. There are several factors to this, such as obesity, environmental factors, family history, genetic factors and monoclonal gammopathies of undetermined significance (MGUS) that have been implicated as potentially etiologic. Development of MM involves a series of complex molecular events, including chromosomal abnormalities, oncogene activation and growth factor dysregulation. Chemotherapy is the most commonly used treatment strategy in MM. However, MM is a difficult disease to treat because of its marked resistance to chemotherapy. MM has been shown to be commonly multidrug resistance (MDR)-negative at diagnosis and associated with a high incidence of MDR expression at relapse. This review deals with the molecular aspects of MM, drug resistance mechanisms during treatment and also possible new applications for overcoming drug resistance. (C) 2015 Elsevier Ireland Ltd. All rights reserved.
Citation - WoS: 17
Citation - Scopus: 30
A Performance and profit oriented data replication strategy for cloud systems
(Ieee, 2016) Tos, Uras; Mokadem, Riad; Hameurlain, Abdelkader; Ayav, Tolga; Bora, Sebnem; Ayav, Tolga; Bilgisayar Mühendisliği Bölümü
In today's world, tenants of cloud systems expect timely responses to queries that process ever-increasing sizes of data. However, most cloud providers offer their services without any performance guarantees to their tenants. In this paper we propose a data replication strategy that aims to satisfy performance guarantees for the tenant while ensuring profitability of the cloud provider. Our strategy estimates the response time of the queries, as well as the expenditures that affect the profitability of the cloud provider. The decision of whether to perform replication is determined by the fulfillment of these two criteria. Validity of the proposed strategy is provided by means of a simulation study.
Citation - WoS: 9
Citation - Scopus: 8
Synthesis and characterization of novel high temperature structural adhesives based on nadic end capped MDA-BTDA-ODA copolyimide
(Iop Publishing Ltd, 2018) Acar, Oktay; Varis, Serhat; Isik, Tugba; Tirkes, Seha; Demir, Mustafa M.; Demir, Mustafa
A series of novel copolyimide structural adhesives were synthesized using 4,4'-diaminodiphenyl-methane (MDA), 3,4'-oxydianiline (ODA) and 3,3',4,4'-benzophenonetetracarboxylic acid dianhy-dride (BTDA) as co-monomers, and nadic anhydride as an end cap reagent. The adhesives with different MDA and ODA contents were examined in terms of their structure, thermal stability, mechanical properties, and adhesive performance. They have glass transition temperatures (T-g) about 400 degrees C, with thermal stability up to 500 degrees C. The effect of diamine monomer compositions on adhesion performance and processability of the copolyimides were studied. The copolyimides exhibited adhesion strength up to 16.3 MPa at room temperature. Nadic end capped MDA-BTDA-ODA copolyimide resins gained adjustable and controllable processability with the addition of ether bridged aromatic segments. The copolyimide adhesive with equimolar composition of MDA: ODA is distinguished form the both commercial PMR-15 and LARC RP-46 polyimides in terms of its better processability and mechanical performance.
Citation - WoS: 4
Citation - Scopus: 9
End-to-end security implementation for mobile devices using TLS protocol
(Springer France, 2006) Kayayurt, Baris; Tuglular, Tugkan; Tuğlular, Tuğkan; Bilgisayar Mühendisliği Bölümü
End-to-end security has been an emerging need for mobile devices with the widespread use of personal digital assistants and mobile phones. Transport Layer Security Protocol (TLS) is an end-to-end security protocol that is commonly used on the Internet, together with its predecessor, SSL protocol. By implementing TLS protocol in the mobile world, the advantage of the proven security model of this protocol can be utilized. The main design goals of mobile end-to-end security protocol are maintainability and extensibility. Cryptographic operations are performed with a free library, Bouncy Castle Cryptography Package. The object oriented architecture of proposed end-to-end security protocol implementation makes the replacement of this library with another cryptography package easier. The implementation has been experimented with different cases, which represent use of different cryptographic algorithms.
Citation - WoS: 4
The importance of protein profiling in the diagnosis and treatment of hematologic malignancies
(Galenos Yayincilik, 2011) Sanli-Mohamed, Gulsah; Turan, Taylan; Ekiz, Huseyin Atakan; Baran, Yusuf; Baran, Yusuf
Proteins are important targets in cancer research because malignancy is associated with defects in cell protein machinery. Protein profiling is an emerging independent subspecialty of proteomics that is rapidly expanding and providing unprecedented insight into biological events. Quantitative assessment of protein levels in hematologic malignancies seeks a comprehensive understanding of leukemia-associated protein patterns for use in aiding diagnosis, follow-up treatment, and the prediction of clinical outcomes. Many recently developed high-throughput proteomic methods can be applied to protein profiling. Herein the importance of protein profiling, its exploitation in leukemia research, and its clinical usefulness in the treatment and diagnosis of various cancer types, and techniques for determining changes in protein profiling are reviewed. (Turk J Hematol 2011; 28: 1-14)
Citation - WoS: 13
Citation - Scopus: 18
Triboluminescent electrospun mats with blue-green emission under mechanical force
(American Chemical Society, 2017) Incel, Anil; Varlikli, Canan; McMillen, Colin D.; Demir, Mustafa M.; Demir, Mustafa
Fibrous mechanosensing elements can provide information about the direction of crack propagation and the mechanism of material failure when they are homogeneously dispersed into the bulk volume of materials. A fabrication strategy of fibrous systems showing triboluminescent (TL) responses is in high demand for such applications. In this work, micrometer-sized Cu(NCS) (py)(2)(PPh3) crystals were synthesized, and polymeric fibrous mats containing the TL crystals were obtained via electrospinning as a stress probe for the determination of mechanical impact. Four different polymeric systems have been employed (PMMA, PS, PU, and PVDF), and the mechano-optical sensing performance of electrospun mats of the polymer-crystal composites was measured. Photophysical properties (quantum yield, band gap, and broadness of the emission) of the TL crystal/electrospun mat composites were also studied. TL and PL emission maxima of the PU-based composite mat show identical behavior due to the chemical affinity between the two structures and the smallest fiber diameter. Moreover, the PU fiber mats exhibit long-lived bluish-green emission persisting over a large number of drops.

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