Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Akkurt, Nevzat(31)
- Gul, Muhammet(11)
- Yucesan, Melih(11)
- Paksoy, Mehmet Yavuz(7)
- Serdar, Osman(7)
- Tanyol, Mehtap(7)
- Torğut, Gülben(7)
- Utku, Anıl(7)
- Xu, Qian(7)
- Aksu, Önder(6)
- Alataş, Mevlüt(6)
- Kocabaş, Mehmet(6)
- Xiong, Yaxuan(6)
- ALMisned, Ghada(5)
- Akmaz, Düzgün(5)
- Alp Dal, Nursel(5)
- Aslan, Naim(5)
- Dal, Nursel Alp(5)
- Du, Yanping(5)
- Eldin, Sayed M.(5)
- Guler, Omer(5)
- Ince, Muharrem(5)
- Qiang, Yujie(5)
- Say, Yakup(5)
- Tekin, H.O.(5)
- Topal, Murat(5)
- Yildirim, Numan(5)
- Yilmaz, Ersen(5)
- Zengin, Gokhan(5)
- Zhang, Hui(5)
- Aksakal, B.(4)
- Basgoz, Oykum(4)
- Can, Umit(4)
- Etli, Serkan(4)
- Ezer, Tülay(4)
- Güler, Ömer(4)
- Pekdemir, Mustafa Ersin(4)
- Pıhtılı, Güzin(4)
- Susam, Selim Orhun(4)
- Tasar, Neslihan(4)
Yayınlar
- MakaleAçık Erişim2022Scopus SJRQ3Effects of kefir supplementation on body antioxidant-systems, haemolymph heat-shock protein 70 and trypsin, in the crayfish Astacus leptodactylus Eschscholtz (Decapoda, Astacidea)
Aksu, Önder; Türkoǧlu, Semra; Can, Erkan; Erişir, Mine; Kocabaş, Mehmet; Kayim, Murathan; Benzer, Fulya
This study was designed to investigate the effects of dietary kefir on trypsin, heat shock protein 70 (HSP70) as well as the oxidant and antioxidant status of the freshwater crayfish, Astacus leptodactylus. The experiment was performed with the four following treatments: Control group, D1, D2 and D3 (kefir supplemented diet 2, 4, 8 g/kg of crayfish body mass, respectively). Crayfish were stocked into 12 fibreglass tanks (three replicates per treatment) and fed for 45 days. Reduced glutathione (GSH), glutathione peroxidase (GSH-Px), malondialdehyde (MDA) and catalase (CAT) in hepatopancreas and muscle were analysed to determine the status of the oxidant/antioxidant balance. In addition, HSP70 and trypsin were measured in haemolymph. Our results indicated that the activity of GSH-Px, MDA and GSH levels decreased in hepatopancreas ( p > 0.05) and muscle tissues ( p < 0.05) with increasing kefir concentration, while CAT activity increased ( p < 0.05). Trypsin and HSP70 insignificantly decreased in haemolymph.
AtıfScopus1WoS1OpenAlex1
İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ1Compressible unsteady steam flow and heat transport analysis: a numerical investigation
Hussain, Azad; Arsaln, Muhammad; Rehman, Aysha; Alharbi, Fahad M.; Akkurt, Nevzat; Eldin, Sayed M.; Althobaiti, Saad
The unsteady compressible steam laminar flow associated with heat transfer in fluids in a squared cylinder is examined in this work. The current challenge was created utilizing the CFD approach. The laminar flow is chosen with a low Mach number. With the geometric wall, the flow has a no-slip condition. The pressure on the flow is kept at 0 pas, and the temperature in the flow regime is 305.13. A 0.5 m/s velocity is used to start the flow. With the use of graphics, the effects of time on velocity and pressure distributions are discussed. Different outcomes are also mentioned, such as drag coefficients, lift coefficients, and heat distributions. The velocity drops from 2.5 to 1.6 m/s at t = 7 s in the absence of anybody's force and temperature 305.13 K. Pressure increases from 0.00098 to 0.001 Pas in the flow interval of 10 s. Surface temperature increases from 360 to 375 K in time intervals of 10 s keeping pressure constant. And contour temperature increases from 371.56 to 374.2 K in time intervals of 10 s keeping the pressure constant. This information provides us with caution about the emission of steam from the chimneys of furnaces. It implies that when steam flows from a cylindrical geometry like chimneys of furnaces it heats the upper inner and outer parts which may destroy the material. So for safety, that emission should be taken for a short interval of time otherwise it will result in a havoc process. The lift coefficient remains constant and the drag coefficient increases from 0.0005 to 0.065. Under that condition, fluid has to face more resistance. To overcome that difficulty fluid should be provided with high velocity to continue it for a long time. The technique used to solve modeled problems is the Backward Difference Formula.
- MakaleYalnız künye2022Scopus SJRQ3On the investigation of a discontinuous Sturm-Liouville operator of scattering theory
Akcay, Ozge
This paper deals with the investigation of the direct scattering problem for the Sturm-Liouville operator containing both the discontinuous coefficient and discontinuity conditions at some point on the positive half-line. The integral representation of the Jost solution is obtained and the properties of its kernel function are given. A total collection of the scattering data is constructed and the behavior of the scattering function at infinity is examined.
AtıfScopus2İncele - MakaleAçık Erişim2022Scopus SJRQ3The use of Phanerochaete chrysosporium as an alternative bioremedia-tion tool of heavy metal, chemical oxygen demand and phosphate from landfill leachate
Yildirim, Numan; Kardas, Elif; Ince, Muharrem
In this study, in order to investigate the bioremediation efficiency of Phanerochaete chrysosporium, chemical oxygen demand (COD) reduction, total phosphate levels and heavy metal (Fe2+, Mn2+, Zn2+ and Cu2+) removal were determined in five different experimental groups (control, X, Y, Z, and T) under static culture conditions containing leachate at different incubation periods (5, 10, and 20 d). At the end of the 20th day of incubation, 84% Mn2+ and Zn2+ removal was achieved in X application group. In the same application group, 90.88% COD reduction was also obtained. The lowest total phosphate value was determined as 2.63 g L–1 in T group compared with control group (5.0 g L–1). Similar improvements have been identified in other application groups in terms of metal removal, total phosphate levels and COD reduction. As a result, the findings obtained from our study show that white rot fungus P. chrysosporium can be used as an alternative biological resource in the studies for improving landfill leachate in terms of metal removal efficacy, COD and total phosphate level reduction capacity.
AtıfScopus3WoS1OpenAlex3İncele - MakaleYalnız künye2022Scopus SJRQ2Fe3O4 nanoparticle decorated novel magnetic metal oxide microcomposites for the catalytic degradation of 4-nitrophenol for wastewater cleaning applications
Hasanoğlu Özkan, Elvan; Aslan, Naim; Koç, Mümin Mehmet; Kurnaz Yetim, Nurdan; Sarı, Nurşen
Co3O4, NiO and ZnO microparticles were decorated with Fe3O4 nanoparticles where novel Co3O4@Fe3O4, NiO@Fe3O4 and ZnO@Fe3O4 microcomposites were obtained with significant magnetic properties. Decorating microparticles with Fe3O4 nanoparticles helped us to obtain microcomposites with outstanding magnetic characteristics, since Fe3O4 nanoparticles were decorated on the upper shell of the microstructures where the magnetic characteristics of the composites were not suppressed, and good catalytic performance was obtained. SEM was used to assess the physical morphology of the microparticles which indicate that microparticles were in flower or ball-like shape. Magnetic properties were checked using VSM which revealed that magnetic composites are in ferromagnetic characteristics. Optic characteristics of the particles were checked by UV–Vis spectrometry to assess bandgap energies which indicate that doping microparticles with Fe3O4 slightly alters the bandgap energies of microparticles. The catalytic role of microparticles and microcomposites for the catalytic reduction of 4-nitrophenol to 4-aminophenol was studied.
AtıfScopus21WoS22OpenAlex18İncele - MakaleAçık Erişim2022Scopus SJRQ2Age- and Sex-Specific Bioaccumulation of Selected Metals in Freshwater Mussel (Unio elangatulus eucirrus Bourguignat, 1860) Populating from Keban Dam Lake (Elazig, Turkey)
Danabaş, Durali; Kutluyer, Filiz; Ural, Mesut; Özçelik, Mehtap; Kocabaş, Mehmet
In aquatic life, environmental chemicals are accumulated by mussels due to their sentinel nature and filter-feeding characteristics. Herein, the present study focused on assessing the concentrations of Cu, Zn, Mg, Mn, Fe, Cd, Pb, Ca, K, and Na levels in freshwater mussels (Unio elangatulus eucirrus) depending on sex and age. For all trace metals, some important differences of bioaccumulations were determined depending on ages and sex. In details, the results indicated that an important age-related accumulation of Mg, Cd, Ca, and K was in females and all trace elements, except Cu, Mg, and K levels in males (p < 0.05). No statistical differences were determined in mean concentrations of Cu, Zn, Mg, and Na. There are statistical differences in Mg, Mn, Fe, and Ca levels between females and males in four aged mussels (p < 0.05). Lead levels were under detectable limits. Overall, metal levels and their toxicity in freshwater mussels should be closely monitored for health of the environment, animals, and humans, since mussels and fish species fed on them are consumed highly in the research region and around.
AtıfScopus5WoS6OpenAlex7
İncele - MakaleAçık Erişim2022Scopus SJRQ1Analysis of turbulent wall jet impingement onto a moving heated body
Coşanay, Hakan; Öztop, Hakan F.; Gür, Muhammed; Bakır, Eda
Purpose: The purpose of this study is to make a numerical analysis of a wall jet with a moving wall attached with a heated body. The hot body is cooled via impinging wall jet. Thus, a jet cooling problem is modeled. The Reynolds number is taken in three different values between 5 × 103 ≤ Re ≤ 15 × 103. The h/H ratio for each value of the Re number was taken as 0.02, 0.04 and 0.0, respectively. Design/methodology/approach: Two-dimensional impinged wall jet problem onto a moving body on a conveyor is numerically studied. The heated body is inserted onto an adiabatic moving wall, and it moves in +x direction with the wall. Governing equations for turbulent flow are solved by using the finite element method via analysis and system Fluent R2020. A dynamic mesh was produced to simulate the moving hot body. Findings: The obtained results showed that the heat transfer (HT) is decreased with distance between the jet outlet and the jet inlet. The best HT occurred for the parameters of h/H = 0.02 and Re = 15 × 103. Also, HT can be controlled by changing the h/H ratio as a passive method. Originality/value: Originality of this work is to make an analysis of turbulent flow and heat transfer for wall jet impinging onto a moving heated body.
AtıfScopus33WoS34OpenAlex33İncele - MakaleYalnız künye2022Scopus SJRQ3Ricci tensor on normal metric contact pair manifolds
Una, I.; Sarı, R.; Prakasha, D.G.
In this paper we study NMCP manifolds, which are (2p+2q+2)−dimensional differential manifolds with an normal metric contact pair structure. The aim of the study is to examine the Riemannian geometry of normal metric contact pair manifolds under certain conditions related to the ⋆−Ricci tensor. We prove that a⋆−Ricci-semi-symmetric NMCP manifold is ⋆−Ricci-flat, and that a ⋆−generalized quasi-Einstein NMCP manifold cannot be ⋆−Ricci-semi-symmetric. Finally, we consider the concircular curvature tensor on NMCP manifolds and prove that a concircular flat NMCP manifold is locally isometric to (2p+2q+2)-dimensional hyperbolic space
AtıfScopus1İncele - MakaleYalnız künye2022Scopus SJRQ1Mitotic effects of copper oxide nanoparticle on root development and root tip cells of Phaseolus vulgaris L. seeds
Tasar, Neslihan
Copper oxide nanoparticle (CuO NP) is used widely in many fields in nanotechnology. For this reason, both production, use, and release to the environment are increasing with each passing day. With the increased use of products that contain nanoparticles (NP) (<100 nm), plants and organisms that constitute the food chain are at risk. In the present study, Phaseolus vulgaris L., a very common food plant, was exposed to metal-based CuO NPs. The anomalies that were caused by CuO NP in germination and mitosis of P. vulgaris were investigated. In the trials, a total of 4 groups (Control, 50, 150, and 300 ppm) were formed and examined in three replications. The determination of the accumulation and elimination rate because of NPs in P. vulgaris that was used in the study was made through X-ray diffraction (XRD), scanning electron microscope (SEM), mapping image, and EDX characteristic spectrum analysis. Also, the mitotic effects on germination, root development, and root tip cells of seeds that were grown by treatment with control, 50, 150, and 300 ppm concentrations were investigated. The study was conducted in three replications in a laboratory setting. All concentrations of CuO NPs caused significant decreases in the mitotic index in the root tip cells of P. vulgaris when compared to the control. The mitotic index reached the lowest level, especially at the highest concentration. Multiple analyzes in the study showed that CuO NPs cause abnormalities in cell division such as C-metaphase, distorted metaphase, distorted anaphase and telophase, chromosome breakage, asynchronous division, advanced chromosomes, micronucleus, and loss of genetic material. These findings also support that the Cytogenetic Test of P. vulgaris can be used to evaluate the genotoxicity of new nanomaterials that are used in many consumer products. In this respect, NPs that are taken up by the organisms in the food chain may pose a danger to higher consumer organisms when they accumulate in the tissue. A control mechanism must be established for the use and contamination of these particles and wider studies must be conducted regarding their effects. Highlights: The effects of CuO nanoparticle, which has a very wide usage area, on root development and mitosis of Phaseolus vulgaris L. plant were investigated in the study. The abnormalities of mitotic division on interphase, prophase, metaphase, anaphase, and telophase were visualized. Evaluation was made considering scanning electron microscopy (SEM) and X-ray diffraction (XRD) results as well.
AtıfScopus14WoS10OpenAlex16İncele - MakaleAçık Erişim2022Scopus SJRQ2Synthesis and Characterization of Azo Dye Complexes as Potential Inhibitors of Acetylcholinesterase, Butyrylcholinesterase, and Glutathione S-Transferase
Buldurun, Kenan; Aras, Abdülmelik; Turan, Nevin; Turkan, Fikret; Adiguzel, Ragip; Bursal, Ercan
In this study, several metal(II) complexes (Fe, Co, Zn, and Ru) of an azo dye ligand (ADL) that, apart from pyrazole ring (PR), include anisole having (−OCH3) group at the m-substitue of the phenyl (L: (E)-4-((3-methoxyphenyl)diazenyl)-3-methyl-1H-pyrazol-5-amine) were prepared, characterized, and the biological activity studies were carried out. The structures of complexes were identified by elemental analysis, FTIR, UV-vis, mass spectra (Fe(II) and Co(II)), 1H-13C NMR spectra, and TGA-DTA. The azo ligand and its metal complexes were evaluated for their biological properties according to the enzyme inhibitory activities. The lowest Ki values of Co(II) complex against all three GST (19.48±2.17 μM), AChE (22.14±3.74 μM), and BChE (26.39±3.19 μM) enzymes were verified as the most effective enzyme inhibition. The biological activity results suggest that the obtained complexes have good potentials to be used in further analyses to explore new pharmaceutical agents.
AtıfScopus20WoS19OpenAlex18İncele - MakaleAçık Erişim2022Scopus SJRQ1Irreversibility analysis of Ellis hybrid nanofluid with surface catalyzed reaction and multiple slip effects on a horizontal porous stretching cylinder
Naveed Khan, Muhammad; Akkurt, Nevzat; Ameer Ahammad, N.; Ahmad, Shafiq; Amari, Abdelfattah; Eldin, Sayed M; Ali Pasha, Amjad
This paper presents the theoretical and computation irreversibility investigation of the Ellis hybrid nanofluid flow (CuO-Al2O3 nanoparticles) model using both homogeneous and heterogeneous responses toward the horizontal porous stretching cylinder. The Joule heating, thermal radiation, and heat generation/absorption are all factors that affect thermal energy transport, all of which are explored. On the surface of the cylinder, the slip boundary conditions are enforced. Keeping in mind that the nonlinear partial differential equations (PDEs) are converted into nonlinear ordinary differential equations (ODEs), these ODEs are constructed from the mathematical flow model with the aid of proper transformations. With the help of the bvp4c MATLAB built-in method, the nonlinear system equations are tacked numerically. Graphical results are used to discuss the numerical aspects of different parameters. By increasing the curvature parameter, entropy generation increases while fluid velocity decreases. Elasticity and magnetic fields thin boundary layers. Realistically, as liquid porosity increases, momentum boundary layer diminishes.
AtıfScopus36OpenAlex35İncele - MakaleAçık Erişim2022Scopus SJRQ3New national and regional bryophyte records, 69
Ellis, L.T.; Afonina, O.M.; Czernyadjeva, I.V.; Alegro, A.; Šegota, V.; Boiko, M.; Zagorodniuk, N.; Burghardt, M.; Alataş, M.; Aslan, G.
AtıfScopus19OpenAlex21İncele - MakaleAçık Erişim2022Scopus SJRQ2DNA barcoding and phylogenetic analysis of endemic Astragalus nezaketiae and Vicia alpestris subsp. hypoleuca (Fabaceae):Evidence from nrDNA ITS and cpDNA matK and rbcL sequences
Paksoy, Mehmet Y.; Sevİndİk, Emre; Başköse, İsa
In this study, we performed DNA barcoding and phylogenetic analysis using one nuclear (ITS) and two chloroplast DNA regions (matK and rbcL) of endemic Astragalus nezaketiae A. Duran & Aytaçand Vicia alpestris Stev. subsp. hypoleuca (Boiss.) Davis taxa in Turkey. PCR reactions were performed using universal primers. Sequences of the PCR products were edited using BioEdit and FinchTV software and contigs were obtained. All contigs were Blasted at NCBI and similarities were analysed. Using the MEGA 6.0 program, maximum likelihood trees were constructed including some sequences retrieved from NCBI. For Astragalus nezaketiae; in the ITS analysis, Astragalus nezaketiae appeared separately from other species, and for matK, Astragalus nezaketiae appeared together with Astragalus cicer L. However, rbcL tree was polytomic. For Vicia alpestris subsp. hypoleuca; in ITS, rbcL and matK results Vicia alpestris subsp. hypoleuca were found together with Vicia cracca L., Vicia benghalensis L. and Vicia villosa Roth species. Analysis of the combined data revealed similar results with all barcode regions for Vicia alpestris subsp. hypoleuca while different phylogenetic results were obtained for Astragalus nezaketiae.
AtıfScopus3WoS2OpenAlex3İncele - MakaleAçık Erişim2022Scopus SJRQ1Novel of (PLA/PCL blend)/Gd2O3 rare earth oxide nanocomposites: Shape memory effect, thermal, magnetic, and mechanical properties
Özen Öner, Ecem; Pekdemir, Mustafa Ersin; Ercan, Ercan; Say, Yakup; Kök, Mediha; Aydoğdu, Yıldırım
Poly ɛ-caprolactone (PCL) and poly lactic acid (PLA) stand out as biocompatible polymers. In this study, PCL and PLA were blended in 40:60 ratio, respectively, and then the Gd2O3 compound, which is an important earth element oxide, was mixed in PLA–PCL shape memory polymer (SMP) blend at different rates and polymer blend nanocomposites were obtained. First of all, the effects of Gd2O3 oxide on the thermal properties of the SMP blend were determined with a differential scanning calorimeter (DSC) and thermogravimetric analyzer (TGA), and it was determined that Gd2O3 did not have a significant effect on the melting temperature of the blend, while it significantly increased its thermal stability. As a result of the XRD (X-ray diffraction) analysis of the composites at room temperature, it was determined that the semicrystalline blend, with the addition of Gd2O3, increased its crystalline property. When the shape memory effect was examined, it was understood that the additive did not eliminate the shape memory effect. When the magnetic property of the gadolinium oxide-doped composite, which is magnetocaloric oxide, was examined, the magnetic property of the composite changed from diamagnetic to paramagnetic with increasing additives. Finally, the mechanical properties of the shape memory blend composite were investigated and no regular changes were observed in the mechanical properties with increasing Gd2O3.
AtıfScopus38OpenAlex42İncele - MakaleYalnız künye2022Scopus SJRQ2Structural, biocompatibility, and antibacterial properties of Ge–DLC nanocomposite for biomedical applications
Arslan, Mehmet Enes; Kurt, Mustafa Şükrü; Aslan, Naim; Kadi, Abdurrahim; Öner, Sena; Çobanoğlu, Şeymanur; Yazici, Ayşenur
Integrative production of new nanocomposites has been used to enhance favorable features of biomaterials for unlocking ultimate potential of different molecules. In the present study, advantageous properties of diamond like carbons (DLC) and germanium (Ge) like greater biocompatibility and antibacterial attributes were aimed to combined into a thin film. For this purpose, 400 nm DLC–Ge nanocomposite was coated on the borosilicate glasses via the magnetron sputtering and surface characteristics was analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and The Raman spectrum. Biocompatibility analysis were performed by 3-(4,5-Dimethylthiazol-2-yl) (MTT) cell viability assay and Hoechst 33258 fluorescent staining genotoxicity assessments on the human fibroblast cell line (HDFa). Finally, antibacterial properties of DLC–Ge nanocomposite coatings were investigated by Pseudomonas aeruginosa (ATCC 27853) and Staphylococcus aureus (ATCC 25923) bacterial attachment analysis. As a result of magnetron sputtering coating, nearly 400 nm thick DLC–Ge nanocomposite film showed a smooth, a non-porous, and a dense characteristic. Cell viability analysis showed that Ge–DLC coatings permits %95 cell surface growth of fibroblast cells. Also, there were no significant difference in aspect of nuclear abnormalities compared to the (−) control which showed nonmutagenic features of the thin film. Finally, antibacterial attachment analysis put forth that Ge–DLC coatings inhibits bacterial adhesion as %40 and %25 rates for P. aeruginosa and S. aureus bacterial strains, respectively. From these results, DLC–Ge nanocomposites could be proposed as a potential new biomaterial for various biomedical applications.
AtıfScopus20WoS16OpenAlex19İncele - MakaleYalnız künye2022Scopus SJRQ1In vivo and in vitro evolution of the effects of cypermethrin on turbot (Scophthalmus maximus, Linnaeus, 1758) spermatozoa
Beken, Atife Tuba; Saka, Şahin; Aydın, İlhan; Fırat, Kürşat; Suzer, Cüneyt; Benzer, Fulya; Erişir, Mine; Özden, Osman; Hekimoğlu, Müge Aliye; Engin, Serhat
Synthetic pyrethroid pesticide is commonly used in agricultural activities in the Black Sea region during reproduction period of turbot. In this sense, in vivo and in vitro studies have shown that cypermethrin (CYP) could be one of the environmental factors affecting decreasing turbot stocks. In this study, effects of in vivo and in vitro administration of CYP, a synthetic pyrethroid, on sperm kinematics motility (MOT), progressive motility (PM), curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), straight line velocity (STR), amplitude of lateral head (ALH), beat cross frequency (BCF), oxidative stress biomarkers malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and lipid peroxidation (LPO) and also histopathological alterations in gonads were investigated in spermatazoa of turbot (Schopthalmus maximus). Broodstock was supplied from culture origin and used in spawning season, additionally, two (0, 0.187 and 0.218 ppb) and three (0, 1.025, 2.05 and 4.1 ppb) different CYP concentrations were performed for in vivo and in vitro studies, respectively. In vivo and in vitro studies, significant reductions were found in sperm MOT, PM, VCL, VSL, VAP, LIN, and ALH properties depend on the increase in CYP concentrations (p < 0.05). Besides, activities of GSH, GPx, SOD, and CAT increased. In terms of histological alterations, no difference was observed among groups (0, 0.187 and 0.218 ppb) in the maturity stage of the germ cells. According to obtained results, sperm kinematics was affected significantly with increased the dose levels of CYP (p < 0.05).
AtıfScopus6OpenAlex8İncele - MakaleYalnız künye2022Scopus SJRQ2Data-driven predictive modeling of Hubble parameter
Salti, Mehmet; Ciger, Emel; Kangal, Evrim Ersin; Zengin, Bilgin
We redesign the generalized pressure dark energy (GPDE) model, which is covering three common types of pressure parameterizations, with the help of a caloric framework to construct a theoretical ground for the machine learning (ML) analysis of cosmic Hubble parameter. The theoretical setup was optimized to find out appropriate values of its arbitrary parameters with the help of genetic neural network (GNN) algorithm and the most recent observational measurements of Hubble parameter. Since there is a shortcoming that the GNN process does not provide a direct method to calculate errors on the optimized values of free model parameters, we therefore take the Fisher Information Matrix (FIM) algorithm into account to deal with this issue. We see that the best-fitting value of Hubble constant and dimensionless dark energy density are in very good agreement with the most recent observations. Also, we discussed the optimized model from a cosmological perspective by making use of the evolutionary behavior of some cosmological parameters to present additional cosmological aspects of our theoretical proposal. It is concluded that our model implies physically meaningful results. In summary, the constructed model can explain the current accelerated expansion phase of the cosmos via Hubble parameter successfully.
AtıfScopus7WoS5İncele - MakaleAçık Erişim2022Scopus SJRQ1Newly synthesized NiCoFeCrW High-Entropy Alloys (HEAs): Multiple impacts of B4C additive on structural, mechanical, and nuclear shielding properties
Gul, Ali Oktay; Kavaz, Esra; Basgoz, Oykum; Guler, Omer; ALMisned, Ghada; Bahceci, Ersin; Albayrak, M. Gokhan; Tekin, H.O.
High-Entropy Alloys (HEAs) are regarded as potential structural materials for fusion and next-generation fission reactors, which will be required to fulfil growing nuclear energy demands. In this study, a HEA-composite was synthesized by adding B4C to an HEA containing Ni. The microstructure of the obtained HEA-composite was examined and the changes in its mechanical properties were revealed. Additionally, the nuclear radiation shielding properties of the Ni-containing HEA, and the HEA-composite are investigated using experimental and theoretical methods. Our initial findings showed that with the addition of 2.5% B4C to the alloy, the hardness increased more than two times. The addition of B4C to the HEA matrix resulted in a more than 90% and a nearly twofold increase in compressive strength. The shielding qualities of gamma-ray and neutron radiation were investigated using experimental and theoretical approaches. Our findings demonstrated that increasing the B4C reinforcement considerably enhanced the composite material's neutron attenuation capabilities. On the other hand, no significant change in the gamma-ray shielding characteristics of HEA and HEA-composite samples was observed. The gamma-ray shielding characteristics of HEA and HEA-composite samples were compared to those of other alloy shields and commercial products. Our findings indicate that both HEA and HEA-composite samples exhibit superior gamma-ray shielding characteristics when compared to the control samples. It can be concluded that increasing B4C reinforcement may be a multifunctional tool in terms of improving the mechanical properties as well as neutron attenuation properties for advanced applications in nuclear radiation facilities and next-generation fission reactors. Additionally, due to their promising material features and higher gamma-ray shielding capabilities compared to other kinds of alloys and commercial shields, HEAs may be beneficial materials.
AtıfScopus33OpenAlex31İncele - MakaleYalnız künye2022Scopus SJRQ2Theoretical Models for Tie Bar Maximum Axial Force Demand in Composite Plate Shear Walls–Concrete Filled
Polat, Erkan
This paper presents theoretical models developed for the prediction of the maximum axial force demands of tie bars of planar composite plate shear walls–concrete filled (C-PSW/CF). In the development of the theory, a previously benchmarked finite element (FE) wall model was used with some modifications. The results from the FE models were used to demonstrate the formation of the tie bar axial force demands, passive lateral confining pressure, concrete confinement, effectively confined concrete core and to develop theoretical models for the prediction of tie bar maximum force demands. The proposed method accounts for various aspects of wall geometry such as horizontal and vertical tie bar spacings, steel plate thickness, and wall thickness. The predictions of the proposed theoretical models were compared with the predictions of FE analyses by performing a parametric study involving C-PSW/CF having different tie bar spacings, plate thickness, wall thickness, and wall depths. Past experimental research available in the literature were used to evaluate the significance of the theoretical model in predicting tie bar maximum axial force demands. Tie bar axial force demand due to the confinement effect is not currently considered in the design of tie bars and there is no theoretical approach in the literature that considers the effect of confinement on the tie bar axial force demand. The theoretical models presented in this study allow the determination of the maximum axial force demands due to the confinement effect on planar C-PSW/CF tie bars without the need for complex and costly numerical analysis.
AtıfScopus7WoS6OpenAlex6İncele - MakaleAçık Erişim2022Scopus SJRQ2Stability Analysis of Buoyancy Magneto Flow of Hybrid Nanofluid through a Stretchable/Shrinkable Vertical Sheet Induced by a Micropolar Fluid Subject to Nonlinear Heat Sink/Source
Khan, Umair; Zaib, Aurang; Ishak, Anuar; Alotaibi, Abeer M.; Eldin, Sayed M.; Akkurt, Nevzat; Waini, Iskandar; Madhukesh, Javali Kotresh
The utilization of hybrid nanofluids (HNs) to boost heat transfer is a promising area of study, and thus, numerous scientists, researchers, and academics have voiced their admiration and interest in this area. One of the main functions of nanofluids is their dynamic role in cooling small electrical devices such as microchips and associated gadgets. The major goal of this study is to perform an analysis of the buoyancy flow of a shrinking/stretching sheet, whilst considering the fascinating and practical uses of hybrid nanofluids. The influence of a nonlinear heat source/sink induced by a micropolar fluid is also inspected. Water-based alumina and copper nanoparticles are utilized to calculate the fine points of the fluid flow and the features of heat transfer. The governing equations are framed with acceptable assumptions and the required similarity transformations are used to turn the set of partial differential equations into ordinary differential equations. The bvp4c technique is used to solve the simplified equations. Dual solutions are presented for certain values of stretching/shrinking parameters as well as the mixed convective parameter. In addition, the shear stress coefficient in the first-branch solution (FBS) escalates and decelerates for the second-branch solution (SBS) with the superior impact of the magnetic parameter, the mass transpiration parameter, and the solid nanoparticles volume fraction, while the contrary behavior is seen in both (FB and SB) solutions for the larger values of the material parameter.
AtıfScopus22OpenAlex27İncele