Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Güler, Ömer(15)
- Utku, Anıl(11)
- Tekin, H.O.(10)
- Zengin, Gokhan(10)
- ALMisned, Ghada(8)
- Güler, Seval Hale(8)
- Serdar, Osman(8)
- Artuğer, Fırat(7)
- Gul, Muhammet(7)
- Paksoy, Mehmet Yavuz(7)
- Unal, Ilkay(7)
- Alataş, Mevlüt(6)
- Aydogdu, Burcu(6)
- Demirbağ, Abdulsamet(6)
- Guler, Omer(6)
- Karaduman, Oktay(6)
- Taşgın, Yahya(6)
- Yucesan, Melih(6)
- Şentürk, Gamze(6)
- Akkurt, Nevzat(5)
- Demirelli, Kadir(5)
- Kavaz, E.(5)
- Kök, Mediha(5)
- Mahmat, Aybars(5)
- Uba, Abdullahi Ibrahim(5)
- Özkul, İskender(5)
- Alkarrani, Hessa(4)
- Barım, Esra(4)
- Batan, Nevzat(4)
- Canbay, Canan Aksu(4)
- Danabas, Durali(4)
- Doğan, Gürkan(4)
- Ergen, Burhan(4)
- Eriani, Kartini(4)
- Fadli, Nur(4)
- Guler, Seval Hale(4)
- Ince, Muharrem(4)
- Kanca, M. Sait(4)
- Kanca, Muhammed Sait(4)
- Karakose, Mehmet(4)
Yayınlar
- MakaleAçık Erişim2024Scopus SJRQ3Four bryophyte species new to Türkiye and South-West Asia
Batan, Nevzat; Taşçi, Nurtaç; Mamontov, Yuriy S.; Erata, Hüseyin; Alataş, Mevlüt; Ezer, Tülay
Scapania praetervisa, Scapania mucronata, Solenostoma confertissimum, and Platyhypnum alpinum found as new to Türkiye following a recent bryofloristic excursion in Artvin region (Caucasian part of Türkiye). Platyhypnum alpinum is also new to Asia. Descriptions, illustrations, distributions, habitat characteristics, and comparisons with morphologically similar taxa are briefly given.
AtıfScopus2OpenAlex7
İncele - Kitap BölümüAçık Erişim2024Recent trends in evaporation techniques
Icier, Filiz; Doner, Deniz; Cokgezme, Omer Faruk; Sabanci, Serdal; Cevik, Mutlu
Increasing energy costs of the food industry and the necessity to reduce emissions of greenhouse gases orient the researchers to find alternative solutions to increase energy efficiency, and to decrease waste and environmental damage. Hence, the use of novel technologies comes to the fore. Since volumetric heating could be provided by Ohmic and microwave heating methods, a heating medium is not required. Thus it is possible to reduce undesirable changes in quality attributes by eliminating contact with hot surfaces and providing rapid heating. The negative effects on the environment could also be reduced owing to both utilization of efficient energy for the heating process and the elimination of wastewater. Alternative nonthermal methods including ultrasound, membrane filtration, pulsed electric field, and electroplasmolysis techniques could also be applied. In this chapter, recent studies on the evaporation techniques, regarding their system setups, effects on the quality characteristics, and performance evaluations are reviewed.
- MakaleAçık Erişim2024Scopus SJRQ2The influence of cold rolling and hydroxyapatite coating on the mechanostructure, corrosion resistance, cell viability, and antibacterial activity of ZnCu biodegradable implants
Aksakal, B.; Karadogan, S.A.; Aslan, N.; Fidan, F.; Yilmazer, Y.; Sezek, S.
Zinc (Zn) and its alloys exhibit great potential for utilization in biodegradable bone implants. Zn-1Cu biodegradable alloy was produced and were cold rolled at two different deformation rates of 47 and 61%. The samples have been bioceramic coated with the sol–gel method and microstructure-mechanical property changes, corrosion behavior and biocompatibility of the samples were investigated. They were characterized by Optical, SEM, XRD and wettability analysis. The rolled samples showed a significant increase in hardness when compared to the non-rolled samples. The unrolled and 47% rolled samples showed better corrosion resistance compared to 61% rolled samples. Antibacterial effects of the base and sol–gel-coated groups showed higher cell viability ratios than the uncoated groups. Cell viability increased significantly in 47% of the rolled samples after 24, 48, and 72 h, however decreased by up to 70% in 61% of the rolled samples. Graphical abstract: (Figure presented.).
AtıfScopus2WoS2OpenAlex2İncele - MakaleYalnız künye2024Scopus SJRQ2Evaluating the metallographic properties and performance of heat transfer by natural convection of graphene-coated glass used for heating
Kahraman, Gökhan; Taşgın, Yahya
In this study, a decorative electric heater was manufactured to reduce carbon emissions related to residential and office heating, and this heater was metallographically evaluated. In addition, the heating performance of the manufactured plate was investigated by examining its heat transfer capacity by natural convection. For this purpose, the surface of the tempered glass plate was coated with graphene by spraying to improve its electrical and heat conduction properties. Copper strips were attached to both sides of the plate to allow for an electric current. The plate was connected to mains electricity, and its change in surface temperature over time was measured. Using the measured temperature values, the heat transfer rate by natural convection on the plate surface was calculated. As a result of the calculations, it was determined that the graphene-coated tempered glass plate reached a heating performance of 40 watts after 2400 s of electrical energy supply. This value can be increased by increasing the heat transfer surface area. This study, taking advantage of the excellent thermophysical properties of graphene, will contribute to other studies conducted in this field.
AtıfScopus2WoS2OpenAlex2İncele - MakaleYalnız künye2024Scopus SJRQ1Ks estimates using macroscopic capillary length estimated from soil hydraulic shape coefficients and Haverkamp infiltration model
Yilmaz, Deniz; Sağlam, Mustafa; İç, Serkan; Stewart, Ryan D.; Lassabatere, Laurent
In this study, we developed a new general approach to estimate the macroscopic capillary length (λc) using different hydraulic function models and related shape parameters, along with the Haverkamp infiltration model constant. We next applied this new approach to the van Genuchten model coupled with a Burdine condition (vGB) to estimate λc. Then, we applied the new λc computation to three different methods for estimating saturated hydraulic conductivity (Ks), and analyzed two sets of constant infiltration data: 1) an analytically generated Beerkan-type dataset and 2) constant head and Beerkan-type infiltration tests performed at the Ambarköprü Experimental Station of Blacksea Agricultural Research Institute in Samsun, Turkey. Our new approach provided accurate Ks estimates when applied to the analytical Beerkan infiltration data. The highest error was observed for a silt soil, with 30 % error for one formulation versus <15 % for the others. For synthetic coarse-textured soils such loamy sand and sandy loam, the error was <10 %. For the field data and Beerkan-type experiments, the new approach gave consistent estimates of Ks regardless of analytical interpretation. However, ANOVA analysis revealed that Ks varied between different infiltration test types, with constant head infiltrometry with 5 cm of applied water head having greater Ks values than the Beerkan tests (p < 0.05). Estimated Ks values also differed between land use types (p < 0.01), with a maize field having significantly greater Ks compared to a soybean field. Overall, we conclude that the proposed approach represents an efficient and appropriate method for characterizing point-scale saturated hydraulic conductivity, so long as experimental artifacts such as ring insertion deep and preferential flows are considered.
AtıfScopus3İncele - MakaleYalnız künye2024Scopus SJRQ2Synthesis and characterization of MgO-doped PHA bio-composites
Aydın, Handan
In this study, a highly useable MgO doped polymer composite of Polyhydroxyalkanoates (PHA), which is an alternative to conventional plastics and an environmentally friendly plastic material due to its biodegradability, was investigated. PHA-MgO composites were obtained by stirring in a suitable solution for a long time with the help of a homogenizer. Then, MgO was added and the changes in Poly Hydroxy Alkonate (PHA) polymer composites were investigated according to the changing MgO ratio. Composites were prepared by adding MgO at different ratios of 1 %, 5 %, 10 % and 15 % into PHA. The structural results of the prepared samples were investigated by using XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscopy). In addition, the thermal properties of the composites were investigated by DSC (Differential Scanning Calorimetry) and TGA (Thermogravimetric Analysis). Furthermore, the optical properties of PHA-MgO composites were determined by UV-VIS spectrometry. Finally, since PHA polymer exhibits shape memory properties, the shape memory properties of the composites were also investigated.
AtıfScopus2WoS2OpenAlex3İncele - DüzeltmeAçık Erişim2024Scopus SJRQ2Correction: Genotoxic effects of copper nanoparticles on Vicia pannonica Crantz. root meristem cells (Journal of Nanoparticle Research, (2024), 26, 8, (185), 10.1007/s11051-024-06096-y)
Tasar, Neslihan
The original version of this article unfortunately contained incorrect Figs. 2, 3, and 4. Lastly, Open access cancellation shall be initiated. The approval manager initially approved the article by mistake, and they approved it above their maximum article threshold by accident. (Figure presented.) (Figure presented.) (Figure presented.) A Adhesion in prophase, B distorted prophase, C metaphase, D distorted metaphase, E non-collection in metaphase plaque, F lagging chromosome in metaphase, G adhesion in metaphase, H chromosome loss in metaphase, I chromosome breakage in metaphase, J asynchronous division in anaphase, K distorted anaphase, L lagging chromosome in anaphase, M polar deviation in anaphase, N chromosome bridges in anaphase, O advance in anaphase, P polar deviation in telophase, R bridge in telophase, S lagging chromosome in telophase, T distorted telophase, U adhesion in telophase (magnification = × 100) A The scanning electron microscopy (SEM) image of the control group, EDS characteristic spectrum, and mapping image. B The scanning electron microscopy (SEM) image of the sample that was prepared with 50 ppm Cu NPs, EDS characteristic spectrum, and mapping image. C The scanning electron microscopy (SEM) image of the sample that was prepared with 150 ppm Cu NPs, EDS characteristic spectrum, and mapping image. D The scanning electron microscopy (SEM) image of the sample that was prepared with 300 ppm Cu NPs, EDS characteristic spectrum, and mapping image The XRD plots of the samples that were obtained from V. pannonica plant grown with Cu (40–60 nm) NP
- MakaleAçık Erişim2024Scopus SJRQ3Synthesis and characterization of chitosan-based pH-sensitive biofilm: An experimental design approach for release of vitamin B12
Onal, Ali; Demir, Hulya; Ince, Olcay Kaplan; Ince, Muharrem
Hydrogels because of their unique potentials, such as highwater content and hydrophilicity, are of interest for the controlled release of drug molecules. In the present study, a biofilm was produced using chitosan, a natural polymer. Characterization analyses of the synthesized biofilm were performed using Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis-differential thermal analysis, x-ray diffraction, and scanning electron microscopy-energy dispersive x-ray spectrometry. The analysis results of the film before loading were compared to the analysis made after adding vitamin B12 to the film. The release percentage of vitamin B12 was investigated by using ultraviolet-visible spectrophotometery. The FT-IR bands of vitamin B12 were in the range of 2,800-3,500 cm-1 and 1,000 cm-1-1,750 cm-1. When pH increased from 3 to 7, release of vitamin B12 from the biopolymer increased up to pH 5. While examining the release potential, parameters, such as pH, initial concentration of vitamin B12, release time, and solution volume, were optimized by using response surface methodology. It was determined that with the increase in release time and the initial concentration, pH contributed positively to the release of vitamin B12. The following conditions were determined for release of vitamin B12 from the biofilm: pH: 4.2, initial concentration of vitamin B12: 54.0 mg L-1, the release time: 117 min, and volume of solution: 2.1 mL. The analysis of variance results showed that the determination coefficients for the use of synthesized biofilm in vitamin B12 release were high and R2 =0.9704.
AtıfScopus9WoS9OpenAlex10İncele - MakaleAçık Erişim2024Scopus SJRQ1Determining the Levels of Cortisol, Testosterone, Lactic Acid and Anaerobic Performance in Athletes Using Various Forms of Coffee
Gür, Melda; Çınar, Vedat; Akbulut, Taner; Bozbay, Kenan; Yücedal, Polat; Aslan, Mehdi; Avcu, Gökçe; Padulo, Johnny; Russo, Luca; Rog, Joanna
Background: Coffee is considered one of the most preferred and consumed beverage types in the world, and caffeine is known to increase physical performance due to its ergogenic properties. The aim of this study is to examine the effects of coffee consumption in different forms on cortisol, testosterone, lactic acid and anaerobic performance levels. Methods: A total of 15 licensed male football players participated in the research voluntarily. The research was implemented in a single-blind, counterbalanced, randomized and crossover study design. Participants were given caffeinated coffee (CK), decaffeinated coffee (placebo) (DK), powdered caffeine (in a gelatin capsule) (PC) and powdered placebo (maltodextrin in a capsule) (PM) on different days, and the Wingate test protocol was performed after the warm-up protocol. Blood samples were collected post-test. Cortisol, testosterone and lactic acid levels in the serum samples taken were determined by the ELISA method. Results: As a result, it was revealed that caffeinated coffee given to participants who exercise increased anaerobic power. However, it was observed that lactic acid levels were higher in placebo and decaffeinated coffee. The highest level of cortisol was found in caffeinated coffee and powdered caffeine compared to the placebo. Testosterone values were observed to be highest in caffeinated coffee and decaffeinated coffee compared to a placebo. Conclusions: The study suggests that the type of caffeine is a factor that affects absorption rate, which impacts performance and hormone levels.
AtıfScopus9OpenAlex12
İncele - BildiriAçık Erişim2024Effect Of The Actıvatıon Force On The Healıng Level Of Asphalt Mıxture Wıth Embedded Capsules
Yalcin, Erkut; Yilmaz, Mehmet; Yalcin, Beyza Furtana; El Naggar, H.; Barros, J.; Cachim, P.
By increasing the asphalt mixtures' inherent capacity for self-healing, encapsulated rejuvenators can extend the service lives of asphalt pavements. The capsules are shattered when crack damage occurs, allowing the rejuvenator ingredient to seep into the cracks. In this work, a brand-new kind of capsule was created. Sunflower oil was a rejuvenator in these capsules. We looked at how well asphalt mixture samples with and without capsules self-healed under static loading. The capacity for self-healing of asphalt mixtures incorporating a novel class of capsules that contain sunflower oil as a rejuvenating agent. For this reason, the ability of the rejuvenating ingredient to diffuse inside of samples of virgin bitumen and the healing potential of combinations of cracked asphalt containing capsules have both been assessed. Due to the mechanical properties of the polymeric capsules examined. Then, using a unique mechanical test, the impact of capsule content on the crack-healing characteristics of asphalt mixtures was assessed at various healing durations (from 5 to 216h) and loads (from 0 to 85kN). As the applied load increases, the healing levels of the asphalt samples with capsules rise; later, the healing levels of the asphalt samples with capsule remain constant. According to the findings, the maximal healing level was typically attained after 96 hours and remained constant until 216 hours.
- MakaleYalnız künye2024Scopus SJRQ2A Study on Comprehensive Production Parameters of Boron Nitride 2D Nanomaterial
Güler, Seval Hale; Safa, Hasan
In this study, BNNSs were synthesized via liquid-phase exfoliation method. Hexagonal boron nitride powders were used as the starting material. The production of boron nitride nanosheets was optimized. For this purpose, different sonication parameters and the effects of different solvents have been investigated. Different sonication power and time parameters of the homogenizer (Sonics Vibra-cell VCX, 750 W) used as the sonication parameter have been changed. In this stage, they were subjected to sonication process first for 1-1.5-2 hours at 25% sonication power, 1-1.5-2-4 hours at 50% sonication power, and 1-1.5-2-4-6-8 hours at 75% sonication power. As a result of particle size analysis, time/sonication power parameters were determined as 2 h-75%, 2 h-50%, 4 h-75%, 2 h-50%. The obtained samples were sedimented with centrifuge process, washed with distilled water to remove solvent, and dried. Different solvents were compared in the best power–time relationship. These solvents are dimethylformamide (DMF), isopropyl alcohol, N-methyl pyrrolidone, ethylene glycol. The best results were obtained in DMF. The synthesized BNNS samples were subjected to particle size (Malvern), scanning electron microscope (Zeiss, Gemini Supra 55), transmission electron microscope (Jeol Jem-1011), Fourier transform infrared spectroscopy (Thermo Scientific Nicolet™ iS™ 5), Raman (WITech alpha 300R), x-ray photoelectron spectroscopy (Specs-Flex), and x-ray diffraction analysis (PANalytical Empyrean).
- MakaleAçık Erişim2024Scopus SJRQ2Hybrid Deep Learning Model for Earthquake Time Prediction
Utku, Anıl; Akcayol, Muhammet Ali
Earthquakes are one of the most dangerous natural disasters that have constantly threatened humanity in the last decade. Therefore, it is extremely important to take preventive measures against earthquakes. Time estimation in these dangerous events is becoming more specific, especially in order to minimize the damage caused by earthquakes. In this study, a hybrid deep learning model is proposed to predict the time of the next earthquake to potentially occur. The developed CNN+GRU model was compared with RF, ARIMA, CNN and GRU. These models were tested using an earthquake dataset. Experimental results show that the CNN+GRU model performs better than others according to MSE, RMSE, MAE and MAPE metrics. This study highlights the importance of predicting earthquakes, providing a way to help take more effective precautions against earthquakes and potentially minimize loss of life and material damage. This study should be considered an important step in the methods used to predict future earthquakes and supports efforts to reduce earthquake risks.
AtıfScopus6WoS5TR Dizin4
İncele - MakaleAçık Erişim2024Scopus SJRQ1A comprehensive microstructural and transmission analysis on oxide dispersion-strengthened (ODS) alloys: Impact of erbium oxide (Er2O3) concentration on physical, structural, gamma-ray, and neutron attenuation properties
Günoglu, Kadir; Güler, Seval Hale; Güler, Ömer; ALmisned, Ghada; Ozkavak, Hatice Varol; Albayrak, M. Gokhan; Akkurt, Iskender; Issa, Bashar; Tekin, H.O.
This study explores the impact of integrating varying concentrations of Erbium Oxide (Er2O3) into Oxide Dispersion Strengthened (ODS) alloys, specifically focusing on gamma-ray and neutron attenuation properties. Utilizing a 316L stainless steel matrix, Er2O3 was methodically incorporated in concentrations ranging from 1 % to 21 % by weight. The structural and radiation attenuation properties of the resultant alloys were comprehensively analyzed using techniques such as X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and experimental gamma-ray transmission studies. The results demonstrate a significant enhancement in gamma-ray shielding with increased Er2O3 content. This enhancement is quantitatively evidenced by increased linear attenuation coefficient, elevated effective Electron Density (Neff), reduced Half-Value Layers (HVL), and higher effective atomic numbers (Zeff). These findings are crucial for nuclear applications where efficient gamma-ray shielding is paramount. Conversely, a decrease in the effective removal cross section (ΣR) for neutron attenuation was observed with higher Er2O3 concentrations. This suggests a potential compromise in neutron shielding efficiency, attributed to the dilution of neutron-absorbing base elements in the alloy. Additionally, the study reveals notable changes in the microstructural properties of the alloys, including alterations in particle size, distribution, and agglomeration, influenced by varying Er2O3 concentrations. In conclusion, this research provides valuable insights into the design of ODS alloys for nuclear radiation shielding, highlighting the balance between gamma-ray attenuation and neutron shielding properties. The study's findings contribute to the development of advanced materials for safer and more efficient nuclear technology applications.
AtıfScopus20OpenAlex25İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1Revisiting the depositional age and provenance characteristics of metasedimentary rocks from the basement units in the Central Pontides (N Turkey): New constraints for tectonic evolution of the southern Black Sea region
Çimen, Okay; Ali Gücer, Mehmet; Akal, Cüneyt; Cemal Göncüoğlu, Mehmet; Arslan, Mehmet; Simonetti, Antonio; Karaoğlan, Fatih
The pre-Jurassic tectonic evolution of the Central Pontides in northern Turkey is still poorly understood due to the lack of detailed geochemical and geochronological data from the basement units. Therefore, this study reports for the first time combined whole rock geochemistry, trace element data and U-Pb ages for detrital zircons, and Ar-Ar geochronological data from the metasedimentary rocks of the Devrekani Massif, Geme Complex, and the Serveçay Unit to better understand their provenance, depositional age characteristics, and tectonic evolutions. The detrital zircon U-Pb data of metasedimentary units from the Devrekani Massif, Geme Complex, and the Serveçay Unit yield ca. 191, 185 and 298 Ma maximum depositional ages (youngest age peaks), respectively. The Devrekani Massif is dominated by Permo-Carboniferous-aged detrital zircons (67 %), whereas Neoproterozoic and Devonian-aged detrital zircons are more common in the Geme Complex (47 %) and the Serveçay Unit (53 %). These distinct age distributions clearly indicate that the Devrekani Massif may has been deposited in a dissimilar location compared to the Geme Complex and the Serveçay Unit. Furthermore, in contrast to the Devrekani Massif, the source area of the metasedimentary rocks from the Geme Complex is comparable with that of the Serveçay Unit. Lastly, the obtained detrital zircon U-Pb and mica Ar-Ar ages suggest that the Devrekani Massif and the Geme Complex were deposited and metamorphosed during the Early and Middle Jurassic, respectively. The Serveçay Unit was deposited and metamorphosed in the Permian.
AtıfScopus5İncele - MakaleAçık Erişim2024Scopus SJRQ2Detection of Threats to Farm Animals Using Deep Learning Models: A Comparative Study
Korkmaz, Adem; Agdas, Mehmet Tevfik; Kosunalp, Selahattin; Iliev, Teodor; Stoyanov, Ivaylo
The increasing global population and environmental changes pose significant challenges to food security and sustainable agricultural practices. To overcome these challenges, protecting farm animals and effectively detecting potential environmental threats is critical for economic and ecological sustainability. In this context, the current study examined the animal detection capabilities and efficiency of advanced deep learning models, such as YOLOv8, Yolo-NAS, and Fast-RNN, across a dataset of 2462 images encompassing various animal species that could pose a risk to farm animals. After converting the images into a standardized format, they were divided into three sets for training, validation, and testing, and each model was evaluated on this dataset during the analysis process. The findings indicated that the YOLOv8 model demonstrated superior performance, with 93% precision, 85.2% recall, and 93.1% mAP50 values, while Yolo-NAS was particularly noteworthy for its high recall value, indicating a remarkable detection ability. The Fast-RNN model also offered significant efficiency with balanced performance. The results reveal the considerable potential of deep learning-based object detection technologies in protecting farm animals and enhancing farm security. Additionally, this study provides valuable insights for future model optimization and customization research.
AtıfScopus9WoS7OpenAlex7İncele - MakaleAçık Erişim2024Scopus SJRQ2A novel convolutional neural network model with hybrid attentional atrous convolution module for detecting the areas affected by the flood
Şener, Abdullah; Doğan, Gürkan; Ergen, Burhan
Natural disasters are sudden and unexpected events that occur as a result of natural processes and often have a significant impact on people, animals, and plants, often resulting in material and emotional losses. Two of the most devastating disasters are floods and tsunamis. After these disasters, search and rescue operations to identify flooded areas are very important to save the lives of affected people and to ensure the health and safety of rescue workers. In this study, a novel semantic segmentation model called Flood Area Segmentation Network (FASegNet) was proposed to guide search and rescue teams in disaster areas to speed up search and rescue operations after natural disasters such as floods, high tides, and tsunamis. The obtained results were compared with common image segmentation models used in various fields. It was found that the developed model achieved higher accuracy rates with fewer parameters. When tested with the "Flood Area" and "Water Body" datasets without pretraining and data augmentation, FASegNet achieved mIoU accuracy of 84.3% and 84.5% respectively.
AtıfScopus23WoS21OpenAlex23İncele - MakaleYalnız künye2024Scopus SJRQ3Tribological properties of the multilayer thin films deposited on the free-form shaped Ti13Nb13Zr alloy
Aslan, Ali Kemal; Bahçe, Erkan
Surface coating processes are carried out to increase the wear and corrosion resistance of products with free-form surfaces used in the biomedical field. In this study, Ti/TiN/TiC/TiCN/TaN multilayer thin films were deposited on the surface of Ti13Nb13Zr alloy samples with different radii of curvature using the closed-field unbalanced magnetron sputtering technique. The wear and adhesion properties of thin films were examined with a specially developed wear test setup, in a simulated body fluid environment and an ultra-high molecular weight polyethylene (UHMWPE) counterpart was used. Scanning electron microscope and X-ray diffraction measurements were used to study the morphology and microstructure of the thin films before and after wear experiments. The delamination amounts of the coatings on the sample surfaces after the wear test were measured and this value was calculated as 8.73%, 12.16%, and 16.89% for the R14, R18, and R22 samples, respectively. As a result of these findings, it was determined that the wear resistance of the coatings decreased as the radius of the curvature increased. The wear amounts of the UHMWPE components are found as 15.45, 6.75, 8.15, 15.45, 6.75, and 8.15 mg for P0, P14, P18, and P22 samples, respectively.
- MakaleYalnız künye2024Scopus SJRQ2Leading and lagging role between financial stress and crude oil
Gençyürek, Ahmet Galip
Purpose: The crude oil market plays a key role in addressing the issue of energy economics. This paper aims to detect the causality relationship between the crude oil market and economy based on the financial system. Design/methodology/approach: This paper used the static and dynamic Hatemi-J Bootstrap Toda–Yamamoto and Diebold–Yilmaz connectedness index. The Hatemi-J Bootstrap Toda-Yamamoto approach allows researchers to use nonstationary data and that method is robust to nonnormal distribution and heteroscedasticity. The Diebold–Yilmaz connectedness index model provides researchers to detect the power of connectedness besides linkage direction. The analyzed period is the span from January 3, 2005 to October 3, 2022. Findings: The results show bidirectional causality in the full sample but unidirectional causality before and after the 2008 financial crisis. During the 2008 financial crisis period and the COVID-19 period, there was a bidirectional and unidirectional causality, respectively. The connectedness approach indicates that the crude oil market affects financial stress through investors’ risk preferences. Research limitations/implications: The Diebold–Yilmaz spillover index model is based on vector autoregression methods with a stationarity precondition. However, some of the five dimensions that constitute the financial stress index (FSI) are nonstationary in level. Therefore, the authors takes the first difference of the nonstationary data. Practical implications: The linkage between the crude oil market and the FSI provides useful information for investors and policymakers. For instance, this paper indicates that an investor wanted to forecast future value of the crude oil (financial stress) should consider the current and past values of financial stress (crude oil). Moreover, policymaker should consider the crude oil market (FSI) to make a policy proposal for financial system (crude oil market). Originality/value: Recently, indicators of economic activity levels (economic policy uncertainty, implied volatility index) have begun to be considered to analyze the relationship between energy and the economy but very little is known in the literature about the leading and lagging roles of data in subsample periods and the linkage channel. The other originality of this research is using the new econometric approaches.
AtıfScopus4WoS5OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ2A comparison of the performance of different innovative trend assessment approaches for air temperature and precipitation data: an application to Elazığ Province (Turkey)
Acar, Ramazan
In this study, the temporal variability of monthly total precipitation and monthly average temperature data of Palu station were analyzed. In addition to statistical analysis such as Mann–Kendall (MK) and SR, innovative polygon trend analysis (IPTA), innovative trend analysis (ITA), and combination of Wilcoxon test and scatter diagram (CWTSD) methods were used in the study. A total of 24 trend analyses (for 12 months of precipitation and temperature data) were conducted for each method used for temperature and precipitation parameters in the study. Look-ing at the results of these methods, a decreasing trend was detected only in December for precipitation data, common to all methods. For temperature data, an increasing trend was detected only in February and March. With the application of the IPTA, an increasing trend in some months and a decreasing trend in other months were detected for the two parameters. The Wilcoxon test exhibits significant consistency with the MK and Spearman's Rho (SR) in terms of the statistical trend, according to the examination of temperature and precipitation data using the CWTSD approach, which is relatively recent. Furthermore, the visual trend analysis demonstrates high consistency between the NO-ITA and Sȩn-ITA approaches.
AtıfScopus23WoS20OpenAlex34İncele - MakaleYalnız künye2024Scopus SJRQ1Exploring Disposal Efficiency of COD, NH3-N, and Turbidity in Diluted Real Leachate Using Ti/PdO-CoO Electrodes in an Electrooxidation Cell: An Investigation into Oxidation Mechanism and Reaction Kinetics Studies
Ogedey, Aysenur; Oguz, Ensar
Highlights Optimum disposal efficiency for turbidity was 96.5 at 10 mM NaCI. Optimum disposal efficiency for COD was 60.5% at 10 mM NaCI. Optimum disposal efficiency for NH3-N was 64.9% at 10 mM NaCI. Turbidity, NH3-N, and COD disposal fitted PFO model due to high R2 values. The Ti/PdO-CoO electrode has a stability of 96 h.
AtıfScopus2WoS2OpenAlex2İncele