Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(86)
- Güler, Ömer(69)
- Akkurt, Nevzat(68)
- Baskonus, Haci Mehmet(53)
- Tekin, H.O.(52)
- Bulut, Hasan(50)
- ALMisned, Ghada(49)
- Serdar, Osman(43)
- Yucesan, Melih(43)
- Paksoy, Mehmet Yavuz(42)
- Yildirim, Numan(41)
- Zengin, Gokhan(40)
- Yildirim, Nuran Cikcikoglu(39)
- Ince, Muharrem(37)
- Kocabaş, Mehmet(37)
- Celik, Erkan(35)
- Benzer, Fulya(33)
- Sulaiman, Tukur Abdulkadir(29)
- Aslan, Naim(27)
- Can, Erkan(27)
- Kutlu, Banu(27)
- Kök, Mediha(27)
- Tanyol, Mehtap(27)
- Danabas, Durali(26)
- Kutluyer, Filiz(26)
- Özkul, İskender(26)
- Ates, Mehmet(25)
- Yildirim, Ozal(25)
- Onat, Onur(23)
- Topal, Murat(23)
- Demir, Veysel(22)
- Erten, Fusun(22)
- Guler, Omer(22)
- Say, Yakup(22)
- Yaman, Mehmet(22)
- Alataş, Mevlüt(21)
- Güler, Seval Hale(21)
- Çimen, Okay(21)
- Baykal, Duygu Sen(20)
- Mete, Suleyman(20)
Yayınlar
- MakaleYalnız künye2024Scopus SJRQ3Allium euphraticum (Amaryllidaceae), a New Species in Sect. Codonoprasum from Eastern Anatolia, Turkey
Sonay, Veysel; Balos, Mehmet Maruf; Çakllclolu, Uur
Allium euphraticum Balos, Sonay & U. Çakllclolu (Amaryllidaceae) is described as a new species in sect. Codonoprasum from Elazl Province, eastern Turkey. It is morphologically similar to A. sultaniae-ferhanii and A. turcicum, but differs from them by, for example, scabrid leaf sheath, backwards curved apex of perigon, creamy and brownish perigon, and presence of teeth at the filament base. Herein, we present a detailed description of the species, along with images, an overview of its habitat and ecological characteristics, and a conservation assessment.
AtıfScopus6OpenAlex5
İncele - MakaleAçık Erişim2024Scopus SJRQ1Preparation of carbon dot/polyaniline composites as voltage based dielectric material for capacitor applications
Coğalmış, Fatma Tuba; Demirelli, Kadir; Barım, Esra; Ük, Nida; Ünlü, Caner; Şenkal, Bahire Filiz; Dere, Ayşegül; Tuncer, Hülya; Yakuphanoğlu, Fahrettin
Polyaniline-carbon dot (CD/PANI) composites were prepared via in-situ oxidative polymerization of aniline in the presence of carbon dots, with specific concentrations carefully controlled during synthesis. The composite was characterized using spectroscopic (FT-IR), morphological (TEM, SEM) and electrical methods. Impedance analysis was employed to investigate the transport behavior of charge carriers in the frequency range of 500 Hz to 10 MHz at 25 °C. This study provides a comprehensive analysis of the dielectric properties of the CD/PANI composite, including dielectric constant, dielectric loss, loss factor, AC conductivity, admittance, impedance, and Cole–Cole plots. The dielectric constant of the CD/PANI composite was 6.97 for 1 kHz at 0.5 V and 12.87 for 1 kHz at 5 V. The values indicate that the increase in the dielectric constant of nanocomposite with increasing voltage. This suggests that CD/PANI composite is a dielectric material whose dielectric constants are controlled by applied voltage. Notably, the dielectric constant increased with rising applied voltage and decreased with increasing frequency. Current-voltage (I-V) measurements revealed that the composite's dielectric parameters could be tuned by varying the applied DC voltage, suggesting its potential as a voltage-dependent dielectric (VDD) material for capacitor applications. Furthermore, the enhanced electrical conductivity indicates that the CD/PANI composite is a promising candidate for next-generation dielectric devices.
AtıfScopus7OpenAlex7İncele - MakaleAçık Erişim2024Scopus SJRQ2New sulfa drug derivatives and their zinc(II) complexes: synthesis, spectroscopic properties and in vitro cytotoxic activities
Şahal, Hakan; Öz, Samet; Keskin, Tuba; Tekin, Suat; Canpolat, Erdal; Kaya, Mehmet
Synthesis of four sulfa drug derivatives (L1–L4) and Zn(II) complexes derived from sulfonamide group antibiotic substances was carried out using the hydrothermal technique (HT) and their structures of the obtained compounds were explained using elemental analysis (EA), FT-IR and NMR (1H- and 13C-). Cytotoxic activities of four novel sulfa drug based-Schiff base compounds and their Zn(II) complexes were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay using MCF-7 (human breast cancer), Caco-2 (human colorectal adenocarcinoma), A2780 (human ovarian cancer) and LNCaP (human prostate adenocarcinoma) cell lines. LogIC50 values of all obtained compounds were computed with the Graphpad Prism 6 program after 24 h of treatment for MCF-7, Caco-2, A2780 and LNCaP cells. Comet assay experiments were performed using LogIC50 concentrations of all compounds to determine DNA damage. Based on the data obtained, all compounds significantly decreased MCF-7, Caco-2, A2780 and LNCaP cell viability compared to the control groups (p < 0.05).
AtıfScopus6OpenAlex5
İncele - MakaleAçık Erişim2024Scopus SJRQ1Effect of curing conditions on cement based self-compacting mortar produced with mortar waste aggregate
Akgül, Melek
Concrete and mortar wastes, which have a large volume and economic value among construction demolition wastes, are the most targeted demolition waste group to be recycled. An important area where construction demolition waste can be utilized is self-compacting mortar (SCM) systems. SCMs are innovative and economical systems designed to minimize the labor requirements that are difficult to meet in the production process. In this study, mortar waste aggregate (MWA) obtained by mechanical crushing and grinding was used in SCM elements by substituting different ratios (5-10-20-30-40 %) by mass to aggregate. In this way, it was aimed to evaluate both the sustainability of MWAs and the usability of MWAs in SCMs, which are considered as a new production technology. The fresh and hardened mortar tests performed in the study are presented comparatively. The physical (dry unit volume weight, porosity), durability (capillary water absorption) and mechanical properties (flexural tensile, compressive strength) of the hardened SCM elements are based on the determinations made at 3, 7 and 28 test days and according to different curing conditions (water curing, air curing and heat curing). In addition, X-ray Diffractometer (XRD) analysis was performed on specimens obtained from 0 %, 10 %, 20 % and 40 % MWA substituted specimens after heat curing (after 7 days water curing) and 28 days water curing. In the light of the data obtained, it is reported that SCM production with 10 % MWA substitution is feasible in terms of sustainability and engineering properties evaluated in this study.
AtıfScopus2WoS1OpenAlex2İncele - MakaleAçık Erişim2024Scopus SJRQ2Development of new generation cakes fortified with zinc oxide nanoparticles
Kaplan Ince, Olcay; Aydogdu, Burcu; Ince, Muharrem
This study aimed to develop new generation cakes that were fortified with calcined ZnO nanoparticles (CZnO), uncalcined ZnO nanoparticles (UCZnO), beads (B(CZnO)) synthesized by encapsulating the CZnO with sodium alginate (SA), and the beads (B(UCZnO)) synthesized by encapsulating the UCZnO with sodium alginate (SA) and investigated the zinc (Zn) release in fortified cakes in simulated body fluids (SBF). The present study represents a novel method for increasing intestinal absorption and bioavailability of dietary zinc with zinc nanoparticles for use in the preparation of Zn fortified cakes as a dietary supplement to compensate for zinc deficiency in humans. The results revealed that a rapid increase in the release time and rate in the SGF solution was noted in the UCZnO added cakes. It was attributed to increased intestinal absorption and bioavailability as a result of the ultra-small size of ZnO. Also, ZnO release kinetics in SBF was also studied and data were adjusted into different kinetic models involving zero-order, first-order, Higuchi, and Korsmeyer–Peppas models. The present investigation recommends adding UCZnO to the cakes to control and increase the release from the cakes.
AtıfScopus3WoS2OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ3Heracleum munzurense (Apiaceae), a new species from East Anatolia, Turkey and taxonomic position of Tetrataenium lasiopetalum
Duran, Ahmet; Lyskov, Dmitry; Samigullin, Tahir; Paksoy, Mehmet Yavuz
A new species, Heracleum munzurense (Apiaceae), is described from East Anatolia, Turkey. It grows in damp places formation of the Munzur Mountains in the district of Pülümür (Tunceli Province). The taxonomic affinities of the new species were determined by analyzing morphological data and through a molecular phylogenetic study of nrITS/ETS. The new species is morphologically and genetically related to H. apiifolium and H. pastinaca, but differs mainly in stems, leaves, pedicels, rays and petals pubescence, petals size, fruit hairs, and size features. The anatomical structure of the fruit is given. The diagnostic morphological characters of the new species are discussed. In this study, the geographical distribution of the new species and the related taxa H. apiifolium, H. lasiopetalum, and H. pastinaca is mapped. In addition, the habitat, ecology, phenology, and conservation status of the new species are also provided. Tetrataenium lasiopetalum is also closely related to this group of species. Common morphological features and results of molecular phylogenetic study suggest to transfer this species back to the genus Heracleum.
AtıfScopus1İncele - MakaleAçık Erişim2024Scopus SJRQ2Enhancing Fault Location Accuracy in Transmission Lines Using Transient Frequency Spectrum Analysis: An Investigation into Key Factors and Improvement Strategies
Akdağ, Mustafa; Mamiş, Mehmet Salih; Akmaz, Düzgün
Fault location estimation in transmission lines is critical for power system reliability. Various methods have been developed for this purpose, among which transient frequency spectrum analysis (TFSA) stands out as a recent method based on travelling wave (TW) theory. TFSA determines the fault location by analyzing the frequency spectrum of transient currents and/or voltages at the instant of the fault, offering advantages such as independence from fault impedance and the ability to locate faults with one-side measurements. Despite its success in fault location, TFSA has several considerations that warrant detailed investigation. This study explores the effects of source inductance, series compensation, fault arc, and current transformer (CT) characteristics on transient frequencies. Additionally, the impact of noise on TFSA results is examined. The new proposed source inductance compensation method can reduce the error of 6.55% to 0.88%, where the same error can be reduced to 3.45% with the compensation method given in previous study. Strategies to enhance accuracy are discussed and compared to previous studies, including a proposed detection approach providing appropriate data size and precise wave propagation speed calculations. These findings contribute to a deeper understanding of TFSA’s limitations and inform practical improvements for fault location accuracy in power transmission systems.
AtıfScopus6WoS5OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ1A novel technique using integral transforms and residual functions for nonlinear partial fractional differential equations involving Caputo derivatives
Khan, Zareen A.; Riaz, Muhammad Bilal; Liaqat, Muhammad Imran; Akgül, Ali
Fractional nonlinear partial differential equations are used in many scientific fields to model various processes, although most of these equations lack closed-form solutions. For this reason, methods for approximating solutions that occasionally yield closed-form solutions are crucial for solving these equations. This study introduces a novel technique that combines the residual function and a modified fractional power series with the Elzaki transform to solve various nonlinear problems within the Caputo derivative framework. The accuracy and effectiveness of our approach are validated through analyses of absolute, relative, and residual errors. We utilize the limit principle at zero to identify the coefficients of the series solution terms, while other methods, including variational iteration, homotopy perturbation, and Adomian, depend on integration. In contrast, the residual power series method uses differentiation, and both approaches encounter difficulties in fractional contexts. Furthermore, the effectiveness of our approach in addressing nonlinear problems without relying on Adomian and He polynomials enhances its superiority over various approximate series solution techniques.
AtıfOpenAlex1İncele - MakaleYalnız künye2024Scopus SJRQ2Exploring critical behavioral differences in physical, structural, and nuclear radiation attenuation properties of produced High Entropy Alloy (HEA) and Refractory-High Entropy Alloy (RHEA) samples
Güler, Seval Hale; Güler, Ömer; Kavaz, E.; Almisned, Ghada; Issa, Bashar; Tekin, H.O.
Refractory-High entropy alloys (RHEAs) are known for their exceptional mechanical and radiation-resistant properties, making them promising materials for use in nuclear reactors. Their high entropy composition, which consists of multiple elements in roughly equal proportions, can create a stable microstructure that withstands high levels of radiation damage. The objective of this work is to further our comprehension of the unique behavioral, physical, structural, and nuclear radiation attenuation characteristics shown by High-Entropy Alloys (HEA) and Refractory-High entropy alloy (RHEA) materials. Accordingly, two high entropy alloy (HEA) samples through two different compositions were produced. The first composition under consideration is the typical high-entropy alloy (HEA) defined as MnCrFeNiCoMo0.5. The second composition under consideration is a refractory high entropy alloy (RHEA) characterized by the following elemental composition: TiZrNbHfVTa0.1. SEM and EDX analyses were conducted in terms of determining their physical and structural attributes. Next, a133Ba radioisotope together with a HPGe detector were utilized for gamma-ray transmission experiments. Finally, a241Am/Be source and a gas proportional detector were used for neutron absorption experiments for HEA and RHEA samples. The alloy structures displayed a unique degree of uniformity. Throughout the RHEA phase, the incorporation of refractory elements did not provide any discernible adverse impacts on the physical stability. The counting spectrum provided a clear explanation of the gamma ray absorption features shown by the RHEA (R) sample, highlighting its exceptional absorption properties. Regarding the absorption properties of neutrons, it was observed that RHEA had a comparatively reduced amount of absorption. Therefore, it can be concluded that the basic structure of RHEA grants it superior gamma-ray attenuation qualities compared to HEA. It can be concluded that RHEA demonstrates superior applicability as a material in comparison to HEA, especially in situations involving the use of fuel rods, where maintaining of neutron quantity has paramount importance for achieving optimum neutron activation.
AtıfScopus26OpenAlex29İncele - MakaleYalnız künye2024Scopus SJRQ2Effect of type and concentration of antioxidant on sperm motility, viability, and DNA integrity of climbing perch Anabas testudineus Bloch, 1792 (Pisces: Anabantidae) post-cryopreservation
Maulida, Siti; Eriani, Kartini; Fadli, Nur; Siti-Azizah, Mohd N.; Kocabas, Filiz K.; Kocabas, Mehmet; Wilkes, Martin; Handayani, Luvi S.; Rahayu, Sri R.; Muchlisin, Zainal A.
Sperm quality is preserved through the crucial involvement of antioxidants, which play a vital role in minimizing the occurrence of reactive oxygen species (ROS) during the cryopreservation process. The suitability of the type and concentration of antioxidants are species-dependent, and this study is crucial in order to improve the quality of the climbing perch sperm post-cryopreservation. Therefore, this study aimed to determine the best type and concentration of antioxidants for cryopreservation of climbing perch Anabas testudineus sperm. To achieve this, 6 types of antioxidants, namely, ascorbic acid, beta-carotene, glutathione, butylated hydroxytoluene (BHT), myo-inositol, and alpha-tocopherol, with inclusion of a control were tested in 3 replications at three concentration levels of 0 mg/L (control), 20 mg/L, 40 mg/L, and 60 mg/L. Sperm was diluted in a glucose-base extender at a ratio of 1:60 (sperm: glucose base), then 10 % DMSO and 5 % egg yolk was added before cryopreservation for two weeks. The results showed that the type and concentration of antioxidants had a significant effect on the motility and viability of cryopreserved climbing perch sperm (P < 0.05), where the best results for ascorbic acid, beta-carotene, glutathione, myo-inositol, and alpha-tocopherol were obtained at a concentration of 60 mg/L, while BHT was at a concentration of 20 mg/L. The best results for glutathione, myo-inositol, and alpha-tocopherol were significantly different from other treatments, while the best results for ascorbic acid and beta-carotene (60 mg/L) were not significantly different from the 40 mg/L concentration, while the best results for BHT were not significantly different from the control treatments. Therefore, the best concentration of glutathione, myo-inositol, and alpha-tocopherol was 60 mg/L, while for ascorbic acid and beta-carotene it was 40 mg/L, and BHT was not recommended. DNA integrity analysis indicated the absence of fragmentation in all samples, including fresh, control, and treated sperm. Based on practical and economic considerations, myo-inositol at 60 mg/L was recommended for cryopreservation of climbing perch A. testudineus sperm.
AtıfScopus19OpenAlex12İncele - MakaleAçık Erişim2024Scopus SJRQ3Influence of Congored on the Optical, Dielectric and Thermal Behavior of Polymethyl Methacrylate and Polyvinyl Chloride
Yıldırım, Turgay; Barım, Esra; Tuncer, Hülya; Demirelli, Kadir
Polymethyl methacrylate (PMMA)/Congo Red (CR) and polyvinyl chloride (PVC)/CR composite films were prepared on optical glass by the drop method for optical measurements and also prepared as tablets under pressure for dielectrical measurements. The optical transmission spectra measurements for PMMA and PVC film doped with CR showed a highly absorption in the ultraviolet-visible (UV-Vis) optical range (at 353 nm and 518 nm) and considerably blocking in broad visible range (190 nm–640 nm). PMMA/CR and PVC/CR composite films containing congo red at a concentration of 1 wt% showed maximum absorption bands at 290 nm and 416 nm, but their transmittance percentages were reasonably reduced compared to those of pure PMMA and PVC. Both of composites indicated high transmittances between 640 nm and 800 nm. The optical constants of the PMMA/CR and PVC/CR composite films such as optical band energy gaps (Eg) estimated using Tauc’s model, refractive index and reflectance (%) were calculated. UV–Vis, Fourier transform infrared spectroscopy (FTIR) and Thermogravimetry Analysis (TGA) measurements were used to confirm the breakdown of the -N = N- azo group bonds attached to the aromatic ring as a result of thermal decomposition of CR at 500 °C, and it was suggested that N2 gas was eliminated from the CR above 360 °C. The dielectric plots showed that the dielectric constant increased when the CR is doped up to 70 wt% in the polymer matrices. A further increase in the doping concentration of CR resulted in an increase of the dielectric constant. The dielectric constant decreased with an increase in the frequency for all of the samples. The ac (alternating current) conductivity values of PMMA and PVC showed an increase with increasing CR dopant in the polymer composites, while the ac conductivity values were found to be values between those of the pure polymers and CR.
AtıfScopus4WoS4OpenAlex5İncele - MakaleYalnız künye2024Scopus SJRQ2Production of CoCrFeNi(Al/Ti) High-Entropy Alloys by Mechanical Alloying: Optimization of Milling Time and Comparison of Corrosion Susceptibilities
Say, Yakup; Dikici, Burak; Kaseem, Mosab; Özkul, İskender; Güler, Ömer
CoCrFeNi alloy is the most well-known four-component equiatomic alloy. In addition, it has a low-cost composition among HEAs. Four-component alloys are considered semi-HEAs. Therefore, a five-component HEA design was made by adding another metal to the main composition of CoCrFeNi. As the fifth metal, two metals such as Al and Ti, which are relatively low in cost and have the potential to improve properties, were chosen. For this purpose, in this study, the effect of Al and Ti on CoCrFeNi main alloy was investigated by producing three different samples as CoCrFeNi, CoCrFeNiAl, and CoCrFeNiTi. The alloys with three different compositions (used three different samples) were successfully produced by the mechanical alloying method. Although Al and Ti have the possibility of intermetallic with other metals in the alloy, such a formation was not observed during mechanical alloying, and it was observed that all metals were homogeneously distributed in the alloy. The microhardness results indicated that CoCrFeNiAl and CoCrFeNiTi samples had similar hardness values. While the hardness of the CoCrFeNi sample was 136 HV, the hardness of the CoCrFeNiAl sample was 262 HV. However, the hardness of the CoCrFeNiTi sample decreased significantly. The hardness of the CoCrFeNiTi sample was measured as 269 HV. It was observed that the addition of Ti and Al to the base alloy was increased a significant change in hardness. It has been observed that Ti supplementation has a more positive effect on improving corrosion properties. It is seen that the corrosion potentials shift toward more negative potentials with the addition of Al and Ti to the CoCrFeNi (−194 mV) alloy (−306 and −224 mV for CoCrFeNiAl and CoCrFeNiTi, respectively). When the surface morphologies of the alloys are compared after corrosion; the damage to the alloy surfaces increases due to the negative Ecorr value in CoCrFeNiAl and CoCrFeNiTi alloys compared to the master alloy. However, the high corrosion current density (12.69 µA/cm2) in the CoCrFeNiTi sample caused much more damage to this alloy. Graphical Abstract: (Figure presented.)
AtıfScopus14OpenAlex16İncele - MakaleYalnız künye2024Scopus SJRQ2The relationship between parental attitude toward childhood epilepsy and spiritual orientation
Kasimoğlu, Necla; Gürarslan Baş, Nazan
Aim: The aim of this study is to evaluate the relationship between parental attitudes toward childhood epilepsy and spiritual orientations. Methods: This descriptive study was conducted online between May and July 2022 with 417 parents residing in the eastern part of Turkey. Data were collected using a descriptive information form, the Social Attitudes Scale toward Childhood Epilepsies, and the Spiritual Orientation Scale. The obtained data were analyzed using the SPSS software package, employing descriptive statistics such as frequency, percentage, mean, standard deviation, as well as inferential statistics including independent samples t-test, ANOVA, multiple linear regression and correlation tests. Results: The Total Social Attitudes Scale Score toward Childhood Epilepsies was calculated as 45.10 ± 7.81, and the Spiritual Orientation Scale Score was 89.88 ± 30.30 for parents with an average age of 36.64 ± 8.26. It was found statistically significant and high (p > 0.05) for parents who are female, have a higher level of education, and have previously received education about epilepsy regarding both the Total Social Attitudes Scale Score toward Childhood Epilepsies and the Spiritual Orientation Scale Score. A statistically significant positive correlation was found between the Total Social Attitudes Scale Score toward Childhood Epilepsies and the Spiritual Orientation Scale Score. Conclusion: According to the findings of the research, parents' attitudes towards childhood epilepsy are positive, and their spiritual orientation levels are high. As parents' spiritual orientation levels increase, their positive attitudes towards childhood epilepsy also increase.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2024Scopus SJRQ3EFFECT OF CRYOPROTECTANT AND CONCENTRATION ON THE SPERM QUALITY OF WALKING CATFISH, Clarias batrachus, POSTCRYOPRESERVATION
Handayani, Luvi S.; Maulida, Siti; Rahayu, Sri R.; Razi, Nanda M.; Kocabas, Mehmet; Kocabas, Filiz K.; Wilkes, Martin; Siti-Azizah, Mohd N.; Eriani, Kartini; Fadli, Nur
BACKGROUND: Walking catfish, Clarias batrachus is one of the native and most popular freshwater catfish species in Indonesia. However, cultivation faces challenges, particularly due to the scarcity of larvae resulting from underdeveloped breeding technologies. Cryopreservation is a method of storing sperm to maintain viability for a long period and support the breeding technology of the fish. Cryoprotectant, in this context, plays an important role in determining the success of sperm cryopreservation. OBJECTIVE: To determine the best type and concentration of cryoprotectant for cryopreservation of walking catfish sperm. MATERIALS AND METHODS: A total of five different types of cryoprotectants, namely DMSO, glycerol, ethyl glycol, ethanol, and methanol, were tested at four concentration levels namely 0%, 5%, 10%, 15%, and 20%, each with four replications. RESULTS: The type and concentration of cryoprotectant had a significant effect on sperm motility and viability (P<0.05). The best outcomes were obtained with 5% DMSO and ethyl glycol, 10% glycerol and methanol, as well as 15% ethanol. CONCLUSION: The highest motility and viability values were obtained with 5% DMSO, resulting in its recommendation for cryopreservation of walking catfish sperm.
AtıfScopus5OpenAlex3İncele - MakaleYalnız künye2024Scopus SJRQ1Effects of Er2O3 contribution on microstructure and mechanical properties of high entropy and dual phase alloys
Taşgın, Yahya; Malkoç, Aziz; Kanca, M. Sait
The study aimed to look at the differences between a high entropy alloy and a dual phase high entropy alloy with high iron and Mn content. It also wanted to find out what happened when a small amount of the rare earth element erbium oxide (Er2O3) was added to these alloys, especially on the mechanical and microstructure of the alloy. The first step in this study was to get 99 % pure metal powders, which were then made by dividing the powders into 30 g of equal weight. The powders were mixed evenly and then pressed into 10-g blocks under 6 tons of pressure. They were then set up to be melted in an arc. Four of the eight samples that were melted in an arc under vacuum were treated with heat. The four different compositions were then turned into small metallographic samples for SEM, EDX, Mapping, XRD, and microhardness tests. The study's imaging and analysis processes were also carried out. After that, SEM images were taken at various magnifications (100X, 500X, 1000X, 2500X, and 5000X), and EDS and XRD analyses were done on different structures found in these images. These analyses were based on literature research about the clarity of the metallographic images in the alloy, which showed the study's metallographic differences. The samples were put through microhardness and wear tests to see which one was stronger and less worn. The dual phase high entropy alloy (A2) was stronger and less worn than the high entropy alloy (A1). Er2O3 had little effect on the alloys' mechanical properties or microstructure. The heat treatment that was done to the samples helped the metallographic structure. In terms of physics, it didn't change the hardness much, but it did make the material wear less quickly.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2024Scopus SJRQ1Microstructure, mechanical, and cutting performance properties of B4C and SiC reinforced sandwich composite segments
Islak, Serkan; Çelik, Ertuğrul; Erol, Mümtaz; Houssain, Hasaneen
This study aims to extend the work-life of diamond-cutting segments and to economize the operating cost of diamond-cutting tools. In order to achieve this object, bronze matrix sandwich segments reinforced with SiC and B4C were produced utilizing the hot pressing technique. In the term of the cutting segments, it is favorable that the outer layers are wear-resistant and the middle layer is tough. SEM and XRD analysis were used to determine the microstructural properties. Mechanical properties were evaluated by conducting hardness, wear, cutting performance, and three-point bending tests. The cutting performance of the segments was determined by turning andesite marble. SEM examinations showed that SiC and B4C grains were homogeneously distributed in the bronze matrix. The highest hardness value was 113.9 HB in the B4C reinforced sandwich segment. The reciprocating wear test findings indicated that the matrix exhibited the lowest wear rate in the B4C reinforced sandwich composite segment, followed by the hybrid sandwich composite segment. The lowest amount of cutting loss after turning andesite stone was achieved in the SiC, and B4C reinforced hybrid sandwich composite segment. The cutting performance of the hybrid sandwich composite segment increased by 46.15 % compared to the conventional segment without additives. The highest value of the transverse rupture strength of the specimens was 380 MPa for the B4C reinforced sandwich composite segment and 352 MPa for the hybrid sandwich composite segment. Considering all the tests and analyses, the hybrid sandwich composite segment sample may be the most suitable for diamond-cutting tools.
AtıfScopus4WoS4OpenAlex5İncele - MakaleAçık Erişim2024Scopus SJRQ2External oxide layers formed by the oxidation procedure in FeMnSi and FeMnSiCr shape memory alloys and their effects
Tatar, Cengiz; Kök, Mediha; Kanca, M Sait; Tatar, Beyhan
Shape memory alloys are exposed to high temperatures to improve their properties and functionality. Through this process, oxidation inevitably occurs due to the presence of oxygen in the environment, which interacts with the alloying elements. Oxidation adversely affects the hardness of alloys, leading to a decline in their overall quality. In this study, the oxidation behavior parameters of FeMnSi and FeMnSi-Cr alloys and the oxide layers formed during this process were investigated in Fe-based alloys with high usage potential. Both non-isothermal and isothermal oxidation processes were applied to alloys and the oxidation parameters were determined. Subsequently, the changes in the crystal structure, microstructure, and magnetic properties of the alloys subjected to isothermal oxidation at 400-500-600-700-800 °C were investigated. It was found that the oxidation behavior of both alloys intensified with rising oxidation temperatures, as evidenced by crystal structure and microstructural analyses, which indicated deeper penetration into the alloys at elevated temperatures. Furthermore, an increase in magnetization values was noted alongside the oxidation process. A comparison of the oxidation characteristics between FeMnSi and FeMnSi-Cr alloys revealed that the oxidation parameters for the chromium doped FeMnSi alloy were comparatively lower.
AtıfScopus2OpenAlex2İncele - MakaleYalnız künye2024Scopus SJRQ2Effect of repair patch nature on J-integral reduction in notched plates
Houari, Amin; Kouider, Madani; Polat, Alper; Amroune, Salah; Mohamad, Barhm Abdullah; Chellil, Ahmed; Campilho, Raul
Purpose: The purpose of this research is to evaluate the effectiveness of different repair patch materials in reducing the stresses at the crack tip of a 2024-T3 aluminum plate. This involves a numerical analysis using the finite element method (FEM) to estimate the reduction in the J-integral value, with the goal of identifying how various parameters related to the patch materials, adhesive properties and loading conditions influence the structural integrity of the repaired plate. Design/methodology/approach: The methodology of this research involves conducting a numerical analysis using the FEM to estimate the reduction in the J-integral value at the crack tip of a 2024-T3 aluminum plate. Three types of patches – metal, composite and functionally graded material (FGM) – were examined under tensile loading conditions, and Adekit-A140 adhesive was used to bond these repair patches to the aluminum plate. Findings: The analysis considered various parameters, including crack length, the nature of fibers in the composite material, the gradation exponent for FGM patches and the nature of the face in contact with the adhesive for the FGM patch. Additionally, stress analysis was conducted, examining the J-integral values for the plate, shear stress in the adhesive layer and peel stress in the composite patch. The findings highlight that modifying the nature of the repair patch used can significantly enhance the structural integrity of the repaired plate. Originality/value: The study analyzed J-integral values, shear stress in the adhesive and peel stress in the composite patch. Various parameters, including crack length, fiber type, gradation exponent and adhesive contact face nature, were considered. Results demonstrate that the J-integral value can be significantly reduced by altering the repair patch type, highlighting the effectiveness of customized patch materials in enhancing structural integrity.
AtıfScopus4OpenAlex6İncele - MakaleAçık Erişim2024Scopus SJRQ4Experimental Study on Engineering Properties of Recycled Olivine Aggregate Filled CF Reinforced Electrically Conductive Mortars
Dehghanpour, Heydar; Doğan, Fatih; Subaşı, Serkan; Maraşlı, Muhammed
Electrically conductive concretes produced for different purposes were introduced years ago and since then, intensive scientific research has been going on. Studies in the literature have generally been carried out on conventional concretes with electrical conductivity for floor applications. The current study investigates carbon fiber reinforced mortars filled with fine olivine aggregate. Fine aggregate filled mortars are generally produced for building facade applications. Within the scope of the study, the mechanical, electrical, dynamic and microstructural properties of cementitious mortars containing 0.5%, 0.75% and 1.0% carbon fiber and 100% recycled olivine aggregate were investigated. The purpose of performing dynamic resonance tests was to investigate the effect of carbon fiber on damping ratio. 28-Day compressive, flexural, dynamic resonance, ultrasonic pulse velocity (UPV), Leeb hardness and dry density tests of conductive mortar samples obtained from four different mixtures were performed. In addition, 2, 14, 28, 90 and 180 days electrical conductivity tests were carried out to determine their resistivity in different time intervals. The purpose of performing dynamic resonance tests was to investigate the effect of carbon fiber on damping ratio. While a significant positive effect of CF on electrical conductivity and damping ratio was observed, a negligible decrease in mechanical results was observed. Calcium silicate hydrate (C-S-H) structure formed by hydration using olivine filler in the cement mixture confirmed the binding formations.
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İncele - MakaleAçık Erişim2024Scopus SJRQ3ENHANCING MILLING PERFORMANCE OF 6061 ALUMINUM ALLOY WITH NANOCUTTING FLUID AND MQL
Tosun, Nihat; Rasul, Sleman Yahya; Mahmat, Aybars; Tosun, Gul
During the machining of aluminum alloys, the adhesion of chips to the tool affects the performance characteristics. Today, different cooling systems are used to eliminate these negativities. In this study, the effects of end milling using HSS and carbide cutting tools of 6061-T6 aluminum alloy on surface roughness, chip thickness ratio and tool wear were examined using different cooling techniques (dry, minimum quantity lubrication (MQL) and nanocutting fluid). Different cutting speeds (180, 200, 220 m/min) and different feed rates (0.05, 0.06, 0.07 mm/rev) were used in the experiments. According to experimental findings, tool wear and surface roughness decreased at low cutting speed and feed rate by using nanocutting fluid with carbide cutting tools. It has been observed that the chip thickness ratio increases with high cutting speeds using nanocutting fluid and decreases with dry machining and high feed rates. The best milling performance of the aluminum alloy was achieved in experiments using carbide cutting tools and nanocutting fluid.
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