Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Akkurt, Nevzat(15)
- Sayyed, M.I.(8)
- Askin, A.(6)
- Güler, Ömer(6)
- Yildirim, Ozal(6)
- Tekin, H.O.(5)
- Zengin, Gokhan(5)
- ALMisned, Ghada(4)
- Ak, Gunes(4)
- Aslan, Naim(4)
- Gul, Muhammet(4)
- Kök, Mediha(4)
- Lassabatere, Laurent(4)
- Paksoy, Mehmet Yavuz(4)
- Stewart, Ryan D.(4)
- Yilmaz, Deniz(4)
- Çimen, Okay(4)
- Abou Najm, Majdi R.(3)
- Ali, Shahbaz(3)
- Artuğer, Fırat(3)
- Baloglu, Ulas Baran(3)
- Bayrakdar, Cihan(3)
- Dere, Ayşegül(3)
- Di Prima, Simone(3)
- Erguven, Gokhan Onder(3)
- Ilik, E.(3)
- Karataş, Mehmet(3)
- Kavaz, E.(3)
- Kaya, Mehmet(3)
- Keserci, Ferhat(3)
- Kilic, G.(3)
- Mahomoodally, Mohamad Fawzi(3)
- Nadeem, Sohail(3)
- Rodrigues, Maria João(3)
- Serdar, Osman(3)
- Simonetti, Antonio(3)
- Talo, Muhammed(3)
- Xu, Qian(3)
- Zheng, Qiang(3)
- Çılğın, Zeynel(3)
Yayınlar
- MakaleAçık Erişim2024Scopus SJRQ2Cytotoxic, antioxidant, and enzyme inhibitory activities of Centaurea stapfiana extracts and their HPLC-ESI-QTOF-MS profiles: Insights into an unexplored Centaurea species
Zengin, Gokhan; Fernández-Ochoa, Álvaro; de la Luz Cádiz-Gurrea, María; Jiménez, Francisco-Javier Leyva; Uba, Abdullahi Ibrahim; Ak, Gunes; Soomro, Sanam Iram; Balos, Maruf; Cakilcioglu, Ugur; Rodrigues, Maria João
The members of the genus Centaurea have a great interest in pharmaceutical and nutraceutical fields due to their biological potential. Based on this information, we aimed to evaluate the biological properties (antioxidant, enzyme inhibition and cytotoxicity) and chemical profile of the extract of Centaurea stapfiana, an unstudied species. The highest total phenolic content was found in the ethanol/water extract with 32.17 mg GAE/g. A total of 102 of them were identified by HPLC-ESI-QTOF-MS analysis. These compounds were mainly hydroxybenzoic acid and hydroxycinnamic acid as well as flavonoids. In the antioxidant tests, the ethanol/water extract had the best free radical scavenging and reducing ability. However, in the enzyme inhibition test, the ethanol extract was the most active. The extracts were also tested on two tumour cell lines (RAW 264.7 and HepG2) and one non-tumour cell line (S17). The ethanol extract showed the promising effect on HepG2 (cell viability: 28.6 % at 50 g/ml). Furthermore, we examined the interactions between the compounds and enzymatic and cellular targets. A good interaction was found between quercetin-3-xylosyl-(1- > 6)-glucoside and iNOS. In summary, our results suggest that C. stapfiana can be considered as a versatile raw material for the development of health-promoting applications in the pharmaceutical and cosmeceutical fields.
AtıfScopus13OpenAlex14
İncele - MakaleAçık Erişim2024Scopus SJRQ1Morphometric characteristics of glacial cirques and former glaciers in the Geyik Mountains, Western Taurus, Türkiye
Çılğın, Zeynel; Evans, Ian S.; Keserci, Ferhat; Canpolat, Ergin; Bayrakdar, Cihan
Using the Glacier reconstruction (GlaRe) toolbox, reconstructions of former glaciers in the Geyik Mountains, part of the Taurus Mountain system in southern Türkiye, show that an area of 132.5 km2 was glaciated in the last major glaciation, which left clear terminal and hummocky moraines. Glaciers were 1.4 to 12 km long and those from 49 cirques merged to form a broad 75 km2 piedmont glacier in the Namaras Valley, up to 400 m thick. A thorough analysis of morphometry of the 98 Geyik cirques, using the revised Automated Cirque Metric Extraction version 2 (ACME2) toolbox, shows that they are relatively small, with limited widths: the median length/width ratio of 1.29 is unusually high. With size, length and width increase faster than depth, demonstrating strong static allometry. Maximum slope averages 59°, minimum 3.3° and axial 25°. A combination of low hypsometric integral, high axial profile closure and high axial height-length integral is proposed as a measure of cirque development. The main summits are on sharp ridges on cirque crests, showing that they have been lowered by glacial erosion (by cirque development). Glaciation was strongly asymmetric, with cirque vector mean aspect between northeast and north-northeast. This shows the dominance of solar radiation effects, with some modification from westerly winds. Glacier palaeo- Equilibrium Line Altitudes (pELAs) rise northeastwards and cirque floor minimum altitudes (CFAs) rise toward east-northeast, both showing the importance of moist air from the Mediterranean, 38–55 km to the southwest. pELA averages 2208 m above sea level (a.s.l.) (2277 m area-weighted); CFA averages 2234 m. CFA varies mainly with summit altitudes; where related palaeoglaciers are short CFA is somewhat below pELA, but for longer ones it is above. The most likely palaeoclimate to form these glaciers involves a precipitation increase of 53–72 % with a temperature fall of 8 °C compared with present-day. The cirques formed under similar or less severe conditions.
AtıfScopus7OpenAlex15İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1Investigation of in-vitro bioactivity, electrochemical corrosion, wettability and adhesion properties of bioglass-based coatings modified with Y2O3 and Zr on novel β-type Ti-30Zr-5Mo alloys
Dikici, B.; Say, Y.; Zhao, X.; Niinomi, M.; Szechyńska-Hebda, M.
In this study, the in-vitro bioactivity, electrochemical corrosion resistance, wettability, and adhesion properties of bioglass-based coatings modified with Y2O3 and ZrO2 on Ti-30Zr-5Mo alloy were investigated. The coatings were prepared using the sol-gel method and applied to the alloy substrates through dip-coating. The surface morphology and elemental composition of the coatings were analyzed using SEM/EDS and XRD techniques. Potentiodynamic polarization (PDS) and electrochemical impedance spectroscopy (EIS) were employed to assess the electrochemical behavior of the coatings under in-vitro conditions. Contact angle measurements were conducted to evaluate the wettability of the surfaces. Adhesion strength was measured using tensile testing in accordance with ISO 13779-2 standards. Bioactivity tests were performed by immersing the samples in simulated body fluid (SBF). The results demonstrate that the addition of Y2O3 and ZrO2 improves adhesion strength and corrosion potential, but introducing localized galvanic effects that increase the corrosion current density. Besides, the coatings maintained their structural integrity after the bioactivity tests, and promoted new apatite formation.
AtıfScopus9İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1Effect of pretreatment temperature and time on fat bonding and fat reduction in deep-fried surimi
Erol, Nida Demirtas; Cakli, Sukran; Szymczak, Mariusz; Shen, Cangliang; Matak, Kristen E.; Jaczynski, Jacek
Deep frying (DF) is a popular cooking technique resulting in desirable sensory quality. However, DF also results in negative perception related to increased fat uptake and thus poor nutritional quality. In this study, a development of a novel strategy for fat reduction in DF surimi without additives and coatings was attempted. Novel pre-baking and pre-roasting were applied to surimi prior to DF. This novel pre-treatment strategy for DF surimi has not been reported in literature. Total, free, and bonded fat contents and corresponding fat reductions in DF surimi were determined. Cook and moisture losses as well as water holding capacity, expressible moisture, in addition to color and texture were also investigated. Fat uptake during DF of surimi was reduced (P < 0.05) by ≥ 25 % with pre-baking. Pre-baking improved (P < 0.05) or did not (P > 0.05) affect cook and moisture losses, water holding capacity, expressible moisture, color, and texture. However, pre-roasting increased (P < 0.05) fat content and adversely affected most quality parameters. Pre-baking of surimi at lower-temperature (116 °C) for longer-time (12–15 min) followed by DF at lower-temperature (170 °C) for longer-time (4 min) was most optimal for fat reduction, cook and moisture losses, water holding capacity, expressible moisture, color, and texture of surimi.
AtıfScopus6WoS5OpenAlex5İncele - 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 SJRQ1Sustainable use of boron waste and volcanic scoria in slag-based self-compacting alkali-activated mortars: fresh, mechanical and durability properties
Yön, Merve Şahin; Yön, Burak; Karataş, Mehmet; Benli, Ahmet
Sustainable self-compacting alkali-activated concrete (SCAAC) manufacturing is an environmentally friendly concrete that has a reduced carbon footprint than ordinary concrete. Alkali-activated binders have been demonstrated in experiments to reduce concrete's energy consumption and carbon emissions by over 50%. This paper focuses on manufacturing boron waste (BW), volcanic scoria (VS) and ground blast furnace slag (GBFS) incorporated binary and ternary blends of self-compacting alkali-activated mortars (SCAAM). The main objective of this study is to investigate the fresh, mechanical, durability and microstructural properties of SCAAM based on binary and ternary mixtures of BW, VS, and GBFS. SCAAM samples were synthesized at 60 °C and 100 °C for 72 h then exposed to ambient cured at 3, 28 and 90 days. The compressive strength, flexural strength, physical, and sorptivity properties of the SCAAM mixtures, as well as flowability, were investigated. The performance of the produced blends at freeze-thaw exposure were also examined. SEM, and EDS was also used to examine the microstructures of the mixtures. The findings showed that 50% GBFS and 50%VS based SCAAM mixture heat cured at 100oC activated with NS/NH ratio of 3.0 produced a compressive strength of 40 MPa at 90 days. The findings indicated that inclusion of BW to the SCAAM mixtures decreased the compressive strength notably regardless of NS/NH ratio and curing temperature. Inclusion of BW also affected the durability performance negatively.
AtıfScopus38WoS36OpenAlex35İncele - MakaleAçık Erişim2024Scopus SJRQ2Photodetector performance analysis of a hybrid MnPc/DLC device with high photoresponsivity, sensitivity, and On/Off ratio
Unal, Fatih; Aktas, Sitki; Kurt, Mustafa Sukru; Koc, Mumin Mehmet; Coskun, Burhan; Aslan, Naim; Arslan, Tayfun; Gur, Mahmut
The fabrication and characterization of high-performance devices for optoelectronic applications, particularly their response to incident light, are crucial. In this study, a MnPc/DLC device was fabricated using thermal evaporation and magnetron sputtering techniques, and its fundamental optoelectronic properties were characterised. Key diode parameters including barrier height, ideality factor, reverse saturation current, series resistance, and shunt resistance were determined using several methods, such as TE, Ohm's Law, the modified Norde method, and the Mikhelashvili method. The results from these methods were found to be consistent with varying light intensities. Additionally, photodetector parameters of the MnPc/DLC device were measured at ±1 V under light intensities of 20, 40, 60, 80, and 100 mW/cm2, and the findings were compared with the literature. The maximum values for photocurrent, photoresponsivity, photosensitivity, specific detectivity, and on/off ratio were 6.41 × 10−2 A, 2.49 A/W, 2.02 × 105, 5.8 × 109 Jones and 2.06 × 103, respectively. Notably, the photocurrent, photoresponsivity, photosensitivity, and on/off ratio values were found to be significantly higher and more promising compared to those reported in the literature.
AtıfScopus4OpenAlex4İncele - MakaleAçık Erişim2024Scopus SJRQ1Effect of White-Portland cement containing micro and nano silica on the mechanical and freeze-thaw properties of self compacting mortars
Etli, Serkan; Yılmaz, Tekin; Hansu, Osman
This study concentrated to investigate the influences of white-Portland cement (W-PC) containing silica fume (SF: micro-silica (µSi) and nano-silica (nSi)) as replacement (2–4 wt%) on mechanical (strength and durability), physical and microstructural behaviors of self-compacting mortars (SCMs) fabricated at 0.48–0.63 w/b ratios. In keeping with these purposes, besides of carrying out the workability (mini-slump flow: M−SF and V-funnel: V-F) experiments of SCMs, the mechanical and microstructural tests implemented were: unconfined compressive strength (UCS), flexural strength (FS), freeze–thaw (F-T) and scanning electron microscope (SEM) analysis. The outcomes displayed that, in comparison with the control, replacing W-PC by SF (particularly nSi) enhanced the UCS and FS, resisted against F-T durability by lowering the strength losses in UCS and FS. The ameliorated microstructure resulting in a reduction in the number and/or a narrowing in the size of micro-cracks and pores contributed to generate a more compact and consolidated SCM structure for the improving of strength and durability due of pore-filling effect and superior pozzolanic characteristics of µSi and especially nSi, this in turn reduced the permeability of SCM, which has a significant effect on the strength and durability behaviors of the SCM.
AtıfScopus16WoS16OpenAlex19İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ2A new post-processing approach for improvement of nonlinearity property in substitution boxes
Artuğer, Fırat; Özkaynak, Fatih
The main reason that makes chaos theory attractive for cryptology studies is the unpredictable nature of chaotic systems. However, the fact that the statistical and cryptographical properties of cryptographic primitives based on the values obtained as a result of the electronic circuit implementation of a chaotic system are not as good as the designs based on mathematical transformations has occupied the agenda of researchers. One of the most striking examples of this problem in practical applications is substitution-box (s-box) structures. While the nonlinearity value is 112 for s-box designs based on mathematical transformations, this value is in the range of 103–106.75 for s-box designs based on random (chaotic) transformations. Thanks to the post-processing algorithm proposed in this study, it has been shown that this problem can be resolved and the nonlinearity values of chaos-based s-box structures can be improved up to 111.5. It is thought that the proposed post-processing algorithm may have various potential contributions not only to improve the nonlinearity criterion of s-box structures but also to other information security applications such as cryptographic random number generators in future studies.
AtıfScopus19WoS13OpenAlex16İncele - 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 - 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 SJRQ2A first-time fusion of TiNbWMoZrOx high entropy oxide (HEO) with zinc-tellurite glass: Toward superior physical properties
Kilic, G.; Güler, Ömer; Kavaz, E.; Ilik, E.; Guler, Seval Hale; ALMisned, Ghada; Tekin, H.O.
While numerous oxide additives have traditionally been employed to enhance the radiation shielding capabilities of glasses, the unique attributes of high-entropy oxides (HEOs), a group of materials acclaimed in contemporary material science for their distinctive properties have remained unexamined in this specific area. This novel study explores the enhancement of radiation shielding properties in zinc-tellurite glasses through the integration of TiNbWMoZrOx High Entropy Oxides (HEO). Utilizing advanced synthesis techniques, including mechanical alloying and oxidation, the research successfully incorporates HEOs into glass matrices, aiming to improve gamma-ray and neutron attenuation. Characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) confirms the uniform distribution and structural integrity of the HEOs within the glasses. The synthesis of glass samples with a base structure suitable for the molar composition of 25ZnO.75TeO2 (mol%) and glass samples doped with TiNbWMoZrOx (HEO) was carried out using the traditional high-temperature melting and annealing method. The outcomes demonstrate a concentration-dependent increase in shielding efficacy, particularly highlighting the superior performance of glasses doped with 4 mol% of TiNbWMoZrOx (HEC2–4), which exhibit significantly enhanced mass attenuation coefficients, lower half-value layers, and higher effective atomic numbers. This indicates the effective role of HEOs in boosting radiation protection capabilities. Comparative analysis with traditional shielding materials showcases the HEC2–4 glasses' competitive advantage, underlining their potential as a versatile shielding solution. It can be concluded that incorporating TiNbWMoZrOx high entropy oxides into zinc-tellurite glasses significantly augments their radiation shielding properties, offering a novel approach for enhancing protection against gamma-ray and neutron in various applications.
AtıfScopus6OpenAlex5İncele - MakaleYalnız künye2023Scopus SJRQ2Zinc(II) phthalocyanine substituted by sulfonamide derivative: Photophysical and photochemical properties
Şahal, Hakan
Synthesis of two different new compounds, (E)-4-((2‑hydroxy-3‑methoxy-5-nitro benzylidene)amino)-N-(pyridine-2-yl)benzenesulfonamide 1, (E)-4-((2-(3,4-dicyanophenoxy )-3‑methoxy-5-nitrobenzylidene)amino)-N-(pyridine-2-yl)benzenesulfonamide2and 2(3),9(10),16(17),23(24)-tetrakis-[(E)-4-((3‑methoxy-5-nitro-2-(λ1-oxidanyl)benzylidene) amino)-N-(pyridine-2-yl)benzene sulfonamid] zinc(II) phthalocyanine complex 3 was carried out. Their structures were characterized by spectroscopic methods such as Fourier transform infrared, Proton nuclear magnetic resonance, Carbon-13 nuclear magnetic resonance, Ultraviolet-visible, Fluorescence, Matrix-assisted laser desorption/ionization, Time-of-flight mass (except compounds 1 and 2), as well as Elemental analysis. The spectroscopic, photophysical, and photochemical properties of zinc(II) phthalocyanine complex 3, substituted with new benzenesulfonamide derivatives containing different functional groups, were explored in dimethylsulfoxide to determine its usability as a photosensitizer for photodynamic therapy. The effects of the presence of tetra-substituted new benzenesulfonamide groups from the peripheral positions of the zinc(II) phthalocyanine ring on the spectroscopic, photophysical, and photochemical properties were investigated and these properties were compared with the properties of the substituted and unsubstituted zinc(II) phthalocyanines. As a photosensitizer for photodynamic therapy, this new phthalocyanine 3 has well solubility in different kinds of solvents without aggregation sufficient fluorescence properties, ability to produce singlet oxygen, and photostability under appropriate light irradiation.
AtıfScopus8WoS7OpenAlex6İncele - MakaleAçık Erişim2023Scopus SJRQ3Bioremediation of herbicide diquat dibromide from aqueous solution with white rot fungus Phanerochaete chrysosporium
Yildirim, Numan; Ciftci, Emine; Erguven, Gokhan Onder; Durmus, Barbaros
In this study, the fungal bioremediation of herbicide diquat dibromide (DD) by white rot fungus Phanerochaete chrysosporium was studied. After bioremediation, the reduction in toxicity of the remediated media was evaluated by Daphnia magna as a model organism. For bioremediation studies, flask-level batch experiments were performed at different DD concentrations (10, 20 and 50 ppm) under static and agitated conditions. The highest reduction rates of chemical oxygen demand and total organic carbon were determined as 85.92 (for 20 ppm DD) and 87.46% (for 10 ppm DD), respectively under agitated conditions. After bioremediation, D. magna bioassay was used for toxicity assessment during 24, 48 and 72-h periods. In current study, it was observed that P. chrysosporium has very effective bioremediation capacity for diquat dibromide. The D. magna bioassay revealed that P. chrysosporium provides effective reduction in toxicity of diquat dibromide.
- MakaleYalnız künye2023Scopus SJRQ1Analysis of the mechanical behavior and prediction of the plastic zone of a large-diameter buried gas pipeline under ground overload
Xu, Qian; Zhong, Liqiong; Shu, Mengjie; Zou, Zhenwei; Yang, Gang; Zheng, Qiang; Chen, Xingli; Akkurt, Nevzat; Zhang, Hui; Qiang, Yujie
Plastic failure of pipelines caused by ground overload is increasing. The one-dimensional model based on mechanical nodal parameters cannot predict the plastic failure characteristics of the three-dimensional structure of the pipeline. In order to predict the evolution of the plastic failure of the pipeline with the yield strength as the evaluation criterion, a multidimensional model is needed to consider the changes in the external loads and the changes in the mechanical properties of the pipeline along the circumferential and axial directions. In this study, a finite element calculation model for a large-diameter gas pipeline underground overload was established to investigate the law of stress change in the plastic zone. The nonlinear surface fitting method was used to establish the angle fitting model of the plastic zone and the depth fitting model of the plastic zone. The variation of the area of the plastic zone was described, and the reliability of the results was verified. In addition, the accuracy of the fitting model and the cost of the finite element calculation were evaluated. The results showed that the pipeline entered plasticity at a ground load of P = 25 MPa, and the plastic zone developed continuously in the axial and circumferential directions as the ground load increased. The angle and depth increased to 36° and 1.8 m, respectively, at P = 50 MPa. The average absolute errors for the plastic zone depth fitting model and the plastic zone angle fitting model were 6.42% and 6.64%, respectively, both of which can provide an accurate description of the plastic zone. The calculation results of the plastic zone angle fitting model could meet requirements of data processing and analysis. The plastic zone depth fitting model could be used to obtain solutions with higher accuracy, but it increases the cost of finite element simulation.
AtıfScopus6OpenAlex6İncele - MakaleYalnız künye2023Scopus SJRQ2Computational assesment of Carreau ternary hybrid nanofluid influenced by MHD flow for entropy generation
Ramzan, Muhammad; Ali, Farhan; Akkurt, Nevzat; Saeed, Anwar; Kumam, Poom; Galal, Ahmed M.
Tri-hybrid nano-particles in shear rate-dependent viscous fluid are essential for improving heat and mass transmission in many industries. The current study explores the two-dimensional flow of the Carreau-ternary hybrid nanoliquid with a magnetic field over the stretching surface. The heat transport mechanism is deliberated through the applications of thermal radiation and heat source/sink effects. The entropy minimization of the flow of Carreau ternary hybrid nanofluid has also been scrutinized. Further, the concepts of convective conditions are employed for the numerical solution of the existing model. In the present flow analysis, silver (Ag), Molybdenum disulfide (MoS2), and multi-wall carbon nanotube (MWCNT) nanoparticles are studied. Carboxymethyl cellulose (CMC-water) is used as a base liquid. The well-established numerical collocation finite difference scheme and three-stage Lobatto III as the built-in function of the bvp4c solver via MATLAB have been used to solve the system of equations in the form of concentration, energy, and momentum. Numerous features, such as flow speed, temperature, drag friction, and Nusselt number, are described in figures and tables. From the existing model, some key outcomes are that the rising values of the radiation parameter increased the heat transfer rates. Further, it is dissected that the greater importance of the magnetic field parameter declined the entropy generation and velocity of the liquid.
AtıfScopus88OpenAlex96İncele - MakaleAçık Erişim2023Scopus SJRQ1Radiation mechanism on dissipative ternary hybrid nanoliquid flow through rotating disk encountered by Hall currents: HAM solution
Shamshuddin, M.D.; Akkurt, Nevzat; Saeed, Anwar; Kumam, Poom
The energy transition to enhance heat transport during the flow of ternary hybrid nanofluid comprised of Copper (Cu), Iron oxide (Fe3O4), Silicon dioxide (SiO2) nanoparticles and Polymer as base liquid over a revolving disk surface has been reported. From the several existing techniques, adding nanoparticles to standard working fluids is an effective approach that might dramatically improve the rate of heat transfer. The Hall and radiation impacts are also considered. A mathematical model is developed by assuming the flow as incompressible and purely radial in a cylindrical coordinate system and appropriate similarity variables are introduced for problem simplification and dimensionless analysis. The solution of complex generated PDEs was calculated using semi analytical method known as Homotopy Analysis Method (HAM) after translating them into corresponding ODEs. It has been observed that the consequences of thermal radiation, dissipation term, unsteadiness and rotation parameters boost the energy transmission rate and enhances the heat transfer rate of tri hybrid nanofluids. However, Cu-Fe3O4 nanoparticles in the base fluid remarkably magnifies the energy transmission rate. The unitary ternary hybrid nanofluid (Cu, Fe3O4, SiO2) has higher velocity profiles as compared to unitary nano fluid (Cu) and hybrid nano-fluid (Cu-Fe3O4).
AtıfScopus133WoS121OpenAlex138İncele - MakaleAçık Erişim2023Scopus SJRQ1Numerical simulation for peristalsis of Quemada fluid: A dynamic mesh approach
Ali, Shahbaz; Nadeem, Sohail; Akkurt, Nevzat; Ali Ghazwani, Hassan; Eldin, Sayed M.
Introduction: Flow dynamics due to the peristaltic pumping has been the topic of great interest for the researchers. But numerical and analytical analyses for the peristaltic motion are limited where flow domain is deformed real-time. Research on peristalsis has a limitation where theoretical aspects of walls motion are considered, neglecting the real time deformation of the walls. Objectives: This paper aims to propose a more reliable and accurate numerical methodology for peristaltic motions to address the above-mentioned challenge. Stream traces, velocities, and pressure drops along the tube is to be visualized more accurately. Methods: In present study a finite volume based dynamic mesh motion method is adopted to analyze the peristaltic motion of a non-Newtonian Quemada fluid in an axisymmetric channel. The walls and interior domain of the channel is dynamically deformed for a sinusoidal wave traveling on boundary. Results: Simulation of unsteady flow behavior for time t=0s to 2s and amplitude ratio Φ=0.2,0.4,and0.6. predicts fluid trapping phenomenon. Rotation of fluid particles is more prominent for higher amplitude ratios. Pressure gradient increases with increasing amplitude ratios. Conclusion: A novel dynamic mesh method is proposed for peristaltic pumping. It provides more accurate and more physical results for stream traces; pressure drops and velocities along the tube. A limited case of the study validates the theoretical and analytical results already presented in literature; hence the method is reliable.
AtıfScopus10OpenAlex12İncele - DüzeltmeAçık Erişim2023Scopus SJRQ1Corrigendum to “Modeling and numerical simulation of non-Newtonian arterial blood flow for mild to severe stenosis” [Alex. Eng. J. 72 (2023) 195–211, (S1110016823002594), (10.1016/j.aej.2023.03.088)]
Nadeem, Sohail; Ali, Shahbaz; Akkurt, Nevzat; Bechir Ben Hamida, Mohamed; Almutairi, Shahah; Ghazwani, Hassan Ali; Eldin, Sayed M.; Khan, Zareen A.; Al-Shafay, A.S.
The authors regards, In the original article, in Ref. [16], the citation was incorrectly stated as: H. Liu et al., 3D printing of artificial blood vessel: study on multi-parameter optimization design for vascular molding effect in alginate and gelatin, Micromachines (2017) 8. However, upon thorough review and verification, the authors have discovered that the correct citation should be as follows: V. Carvalho, N. Rodrigues, R. Ribeiro, P.F. Costa, R.A. Lima, S.F.C.F. Teixeira, 3D printed biomodels for flow visualization in stenotic vessels: An experimental and numerical study, Micromachines, vol. 11, no. 6, doi: 10.3390/mi11060549. The authors deeply apologize for this oversight and any confusion it may have caused to the readers and the scholarly community. It is crucial to ensure the accuracy and integrity of their citations, and they sincerely regret any inconvenience this may have caused.
- MakaleYalnız künye2023Scopus SJRQ1Modeling the form, distribution and paleoclimatic implications of former glaciers in the Teke Peninsula (Eastern Mediterranean, Turkey)
Keserci, Ferhat; Bayrakdar, Cihan; Çılğın, Zeynel; Evans, Ian S.
The Western Taurus Mountains on the Teke Peninsula, Southwestern Turkey, saw substantial glaciation in the late Quaternary period. Accurate reconstructions of former glacier extent in this relatively marginal area of glaciation are important for establishing the paleoclimate in the Eastern Mediterranean Basin. From west to east, the mountains of Sandıras, Karadağ, Akdağ (Kaş), and Beydağları preserve clear evidence of cirques and moraines, representing glacial valley land systems. This study used calculation tools for Glacier Reconstruction, (GlaRe) and Equilibrium Line Altitude (ELA), with glacier outlines based on the geomorphological evidence and Digital Elevation Models (DEMs), to determine the distribution and ELAs of former glaciers and to estimate paleotemperature and paleo-precipitation during the maximum ice extent. The results are analyzed at three scales: for each glacier, between glaciers and between mountain ranges. While the glaciation was at its peak, we estimate that glaciers covered a total area of 26.4 km2 (1.28 ± 0.08 km2 on Sandıras Mountain, 3.86 ± 0.23 km2 on Karadağ, 16.17 ± 0.970 km2 on Akdağ (Kaş), and 5.09 ± 0.30 km2 in Beydağları): the longest glacier was in Akdağ (Kaş) with a length of 5787 m. Average paleo-ELA (pELA) was calculated as 2077 m a.s.l in Sandıras, 2097 m a.s.l in Karadağ, 2565 m a.s.l in Akdağ (Kaş), and 2468 m a.s.l in Beydağları. Glacier modeling estimated that the maximum ice thickness in Akdağ was 240 m ± 14, and the average thickness 75 ± 4 m. Among these mountains, Karadağ had the lowest elevation to which glaciers descended (1760 ± 16 m a.s.l). Topographic analyses revealed that glaciers formed in the four mountains mostly in the North-facing localities with highest slope values of 18 to 30°. During the maximum glaciation period air temperature depression has been estimated as 8 to 9° Celsius; That required a precipitation increase of some 40 to 60 % compared to present, to produce the former glaciers mapped in the Teke Peninsula.
AtıfScopus10WoS9OpenAlex17İncele