Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(82)
- Akkurt, Nevzat(67)
- Güler, Ömer(66)
- Baskonus, Haci Mehmet(62)
- Bulut, Hasan(60)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(43)
- Yildirim, Numan(42)
- Yildirim, Nuran Cikcikoglu(38)
- Paksoy, Mehmet Yavuz(36)
- Serdar, Osman(36)
- Zengin, Gokhan(36)
- Ince, Muharrem(34)
- Celik, Erkan(33)
- Benzer, Fulya(32)
- Kocabaş, Mehmet(30)
- Sulaiman, Tukur Abdulkadir(30)
- Tanyol, Mehtap(29)
- Yildirim, Ozal(28)
- Aslan, Naim(26)
- Kök, Mediha(26)
- Özkul, İskender(26)
- Ates, Mehmet(25)
- Danabas, Durali(25)
- Kutluyer, Filiz(25)
- Can, Erkan(24)
- Kutlu, Banu(23)
- Onat, Onur(23)
- Demir, Veysel(22)
- Erten, Fusun(22)
- Guler, Omer(22)
- Say, Yakup(22)
- Güler, Seval Hale(21)
- Yaman, Mehmet(21)
- Baykal, Duygu Sen(20)
- Sançar, Taylan(20)
- Susam, Selim Orhun(20)
- Cakilcioglu, Ugur(19)
- Orhan, Cemal(19)
Yayınlar
- MakaleYalnız künye2023Scopus SJRQ2An Estimation Proposal for Engineering Properties of Modified Concrete by using Standalone and Hybrid GRELM
Cemalgil, Selim; Onat, Onur; Aruntaş, Hüseyin Yılmaz
The presented study pertains to an attempt to propose a novel prediction model to predict the flexural and compressive strengths of concrete modulated using steel fiber (SFb) and silica fume (SF). A completed experimental investigation is adopted for the current study, and a research plan is employed. Three different superplasticizers amount (SP), different SF replacement ratios, and a constant amount of SFb were used by the weight of cement to meet the C25 target strength. A sum of 16 distinct mixtures designed by changing SP and SF ratios were developed. Furthermore, SFb was added at a fixed rate of 65 kg/m3 to all planned concrete mixes. In addition, SFb was used to create a 16-mix design. Finally, a total of 32 distinct mix designs were created. Produced, hardened specimens were exposed to two different curing conditions. This research uses the mechanical characteristics of concrete treated with SF, SP, and SFb to estimate by conducting standalone and hybridized generalized extreme learning machine (GRELM) algorithms based on available experimental data in terms of the metaheuristic aspects of this work. With continuous input data, four separate data sets were constructed. Compressive strength and flexural strength were estimated separately. With the aid of the Grey Wolf Optimization (GWO) and Particle Swarm Optimization (PSO) algorithms, binary and ternary hybrid approaches were developed and tested on the data. Four distinct estimation models were suggested. Two quality metrics were used to evaluate the estimation performance: Root Mean Square Error (RMSE) and correlation of determination (R2). The estimation results showed that the hybridized GRELM-PSO-GWO estimation model that was built for prediction was relatively successful in all sets.
AtıfScopus4WoS3OpenAlex2
İncele - MakaleAçık Erişim2023Scopus SJRQ1Physical-Mechanical and Electrical Resistivity Properties of Cementitious Mortars Containing Fe3O4-MWCNTs Nanocomposite
Selen, Veyis; Guler, Omer; Nodehi, Mehrab; Sarı, Ahmet; Yaras, Ali; Gencel, Osman; Gholampour, Aliakbar; Ozbakkaloglu, Togay
Recent growth in materials science and engineering technologies has pushed the construction industry to engage in new applications, such as the manufacturing of smart and electrically conductive products. Such novel uses of conductive construction materials would potentially allow their use in conjunction with various fields, such as those referred to as “Industry 4.0.” The following study uses iron oxide (Fe3O4)-multi-walled carbon nanotubes (MWCNTs) nanocomposites synthesized by chemical vapor deposition (CVD) and incorporated into the cementitious mortars as a substitute for sand at 1, 2, and 3% ratios to enhance the electrical conductivity. Results reveal that the electrical resistivity of cementitious composites decreases (due to the increase in electrical conductivity) from 208.3 to 61.6 Ω·m with both the Fe3O4-MWCNTs nanocomposites ratio and the increasing voltage. The lowest compressive strengths at 7 and 28 days are 12.6 and 17.4 MPa for specimens with 3% Fe3O4-MWCNTs and meet the standards that comply with most applications. On the other hand, the highest porosity was reached at 26.8% with a Fe3O4-MWCNTs rate of 3%. This increase in porosity caused a decrease in both the dry unit weight and ultrasonic pulse velocity (from 5156 to 4361 m/s). Further, it is found that the incorporation of Fe3O4-MWCNT nanocomposites can have a negative effect on the hardening process of mortars, leading to localized air cavities and an inhomogeneous development of cementing products. Nonetheless, the improvement of the electrical conductivity of the samples without significantly compromising their physico-mechanical properties will allow their use in various fields, such as deicing applications with low-voltage electric current.
AtıfScopus7OpenAlex7İncele - MakaleAçık Erişim2023Scopus SJRQ1A novel radial basis Bayesian regularization deep neural network for the Maxwell nanofluid applied on the Buongiorno model
Sabir, Zulqurnain; Akkurt, Nevzat; Ben Said, Salem
The aim of this work is to provide the numerical solutions of the fluid model by using the stochastic computing paradigms. The linear/exponential stretching sheets on magneto-rotating flow based on the Maxwell nanofluid have been provided using the Buongiorno model with the impacts of uneven heat source/sink, varying thermal conductivity and reactive species. The solutions of this transformed ordinary differential exponential stretching sheet model have been presented using a novel ‘radial basis’ (RB) activation function together with the Bayesian regularization deep neural network (BRDNN), i.e., RB-BRDNN. The deep neural network is presented into two hidden layers, while thirteen and twenty-five numbers of neurons have been used in the first and second layer. A reference dataset is proposed using the Runge-Kutta scheme for the model. The correctness of the stochastic RB-BRDNN procedure is examined through the comparison of proposed and database results, whereas minimal absolute error values provide the accuracy of the scheme. The reliability and competence of the computing RB-BRDNN solver is authenticated using the state transitions, correlation, regression, and error histograms.
AtıfScopus33WoS30OpenAlex36İncele - MakaleAçık Erişim2023Scopus SJRQ2Extracting low dimensional representations from large size whole slide images using deep convolutional autoencoders
Çelik, Yusuf; Karabatak, Murat
Background and objective: Artificial intelligence-based analysis of medical images has recently become a trendy field of study. The most significant effect on these systems to produce reliable and high-performance results is the amount of accessed data. Although whole-slide images (WSI), one of the current imaging techniques used in histopathology, storage costs are very expensive. Therefore, low-dimensional visuals representing of WSIs is an essential field of study. Methods: In this study, deep auto-encoder-based models are designed to create low dimensional representations for WSI. The size reduction was performed for the input images in different sizes, at the ratios of 1: 3, 1: 6, and 1: 12, respectively. Results: Similarity index measure values were obtained as high as 0.957 and 0.938, respectively, using 128 × 128 × 3 dimensional patches in the size reduction process of 1: 3 and 1:12 on test WSI. Conclusion: The proposed model has a structure that can be applied in compression of WSIs and secure data transfer. By using these representations, both storage costs and the high-level hardware costs required by deep learning algorithms can be significantly reduced.
AtıfScopus3WoS2OpenAlex4İncele - MakaleAçık Erişim2023Scopus SJRQ3Investigation of the geometry effect on air-demand ratio in conduits with a sluice gate
Aydin, Alp Bugra; Baylar, Ahmet; Ozkan, Fahri; Tuna, Muhammed Cihat; Ozturk, Mualla
Gated conduits involve high-velocity air-water flow. When studies on gated conduits are examined, it is determined that the air-demand ratio changes according to the hydraulic and geometric parameters. However, no study has investigated the effect of the cross-sectional geometry of high-head conduits with a sluice gate on the air-demand ratio. In this study, the effect of conduit cross-sectional geometry on the air-demand ratio is examined. Results indicate that a conduit's cross-sectional geometry has an important effect on the air-demand ratio, especially at 10% and 15% gate opening rates. It is seen that the effect of the conduit geometry on the air-demand ratio decreases at 20%, and for greater gate opening rates. Moreover, a formula for estimated the air-demand ratio is presented, relating the air-demand ratio to the gate opening rate, Froude number, hydraulic radius and conduit length.
AtıfScopus5WoS6OpenAlex4İncele - MakaleYalnız künye2023Scopus SJRQ1Adsorption potential of neodymium/alginate beads for removal of Congo red and Brilliant blue G from aqueous solution
Seker, S.; Karaaslan Ayhan, N.
In this study, neodymium/alginate (Nd/Alg) beads were prepared to removal of Congo Red (CR) and Brilliant Blue G (BBG) dyes from aqueous solution and the adsorption potentials of these dyes were investigated. For this, Nd/Alg beads prepared using crosslinking were characterized by FTIR, SEM–EDS and TGA. For the adsorption of CR and BBG dyes, the effects of various parameters including the amount of Nd in adsorbent (bead), pH, contact time, adsorbent amount, initial dye concentration and temperature were investigated. The optimum conditions for the effective removal of CR and BBG dyes were determined as Nd amount in bead: 3%, pH: 7, contact time: 60 min, bead amount: 15 mg, initial dye concentration: 25 mg/L and temperature 298 K. Adsorption isotherm studies (Langmuir and Freundlich isotherms) and kinetic studies (pseudo-first-order and pseudo-second-order) were carried out under optimum conditions. The adsorption data were found to completely follow Langmuir model for CR and BBG dyes. The maximum adsorption capacities were found to be 46.03 mg/g for CR and 25.25 mg/g for BBG under optimum conditions. The adsorption kinetic data of both dyes were found to be compatible with pseudo-first-order and adsorption processes were explained by intraparticle diffusion. According to thermodynamic studies, nature of adsorption reaction was spontaneous, exothermic and increasing randomness for both dyes. As a result, it can be concluded that Nd/Alg beads obtained with a natural polymer have low cost and high efficiency and even small amounts of these beads have high potential for treatment of high concentration dye wastewater.
AtıfScopus10WoS8OpenAlex10İncele - MakaleAçık Erişim2023Scopus SJRQ2Chaotic quantization based JPEG for effective compression of whole slide images
Artuğer, Fırat; Özkaynak, Fatih
In today’s digital world, effectively transferring data from one point to another is an important problem. For this reason, the development of various new compression algorithms and making existing solutions more effective are examined in detail by researchers. In this study, a new method is proposed to improve the performance of JPEG algorithm. The proposed method includes an approach based on chaotic systems. Chaotic systems contain a strong entropy source. This powerful source of entropy has strong practical applications in obtaining statistically robust random values. In this study, a method is proposed to obtain quantization tables effectively by taking advantage of this potential of chaotic systems. The obtained results showed that the compression performance can be increased at the same quality factors. The proposed approach has been tested on the whole slide image (WSI) dataset. Looking at the analysis results, an average of 2.43% higher accuracy was achieved compared to the JPEG algorithm. It is thought that these results can provide an advantage especially in transferring high-dimensional images such as the DICOM standard, where the JPEG algorithm is used in practical applications.
AtıfScopus5WoS4OpenAlex7İncele - MakaleYalnız künye2023Scopus SJRQ2Effect of impactor nose form on the impact behavior of reinforced composite materials
Dogan, Sonay; Arman, Yusuf; Dogan, Akar
The goal of the present study is to investigate the influence of impactor shape on the low-velocity impact behavior of the composite panels manufactured with different reinforcement materials at the same thicknesses, experimentally. Kevlar, carbon, S-2 glass woven fabric and epoxy matrix have been used to manufacture thermoset composites with the vacuum-assisted resin infusion molding method. The Fractovis plus test machine with a 12.7 mm diameter hemispherical and two different conical impactor noses was used to perform impact tests. The effects of impactor shapes on the low-velocity impact behavior have been compared for 20 J, 40 J, and 60 J energy levels. Although at the same impact energy level, S-2 glass fiber-reinforced epoxy specimens have a higher perforation threshold than carbon and Kevlar fiber-reinforced epoxy. Because to achieve the same thickness, the number of S-2 glass layers was greater than the number of carbon and Kevlar layers. Additionally, the form of the impactor greatly influenced the perforation threshold.
AtıfScopus7WoS7OpenAlex6İncele - DüzeltmeYalnız künye2023Scopus SJRQ1Corrigendum to “A study on the combustion performance and NOx emissions characteristics of a novel U-type radiant tube based on MILD combustion theory” [Fuel 346 (2023) 128321] (Fuel (2023) 346, (S0016236123009341), (10.1016/j.fuel.2023.128321))
Fan, Huanbao; Feng, Junxiao; Bai, Wei; Wang, Hui; Akkurt, Nevzat; Li, Weidong; Gao, Jun; AliAkbaria, Omid; Xu, Qian
The authors regret to inform that Table 1 in the final (citable) version of our article [Fuel 346 (2023) 128321] published in Fuel has a serious error; some key data in Table 1 (page 4, Section 2.2) corresponded incorrectly to variables. This was mainly due to our carelessness and was not caught in time while reviewing proofs for our publications. The correction is necessary to improve the academic accuracy of the article and for ease of reference for the readers. We are therefore publishing this correction. Specifically, the pre-exponential factor Ar and activation energy Ea of 2CO + O2 → 2CO2 should be 2.239 × 1012 1/s and 1.7 × 108 J/kg·mol, respectively. The pre-exponential factor Ar and activation energy Ea of 2H2 + O2 → 2H2O should be 9.87 × 108 1/s and 3.1 × 107 J/kg·mol, respectively. Thank you for your understanding and the previous efforts of all the reviewers and editors. Reference [1] Huanbao Fan, Junxiao Feng, Wei Bai, Hui Wang, Nevzat Akkurt, Weidong Li, Jun Gao, Omid AliAkbaria, Qian Xu, A study on the combustion performance and NOx emissions characteristics of a novel U-type radiant tube based on MILD combustion theory, Fuel 346 (2023) 128321. DOI: https://doi.org/10.1016/j.fuel.2023.128321. The correct version of Table 1 is as follows: The authors would like to apologise for any inconvenience caused.
- MakaleYalnız künye2023Scopus SJRQ3Trematodon and Ptychostomum Species New to Turkey and South-West Asia
Erata, Hüseyin; Batan, Nevzat; Alataş, Mevlüt; Ezer, Tülay
Abstract: During the recent bryofloristic studies in the Karçal mountain of the Artvin region (Caucasus), north of Turkey’s East Black Sea region, Trematodon ambiguus and Ptychostomum cyclophyllum were found as new species to Turkey and Southwest Asia. Descriptions, illustrations, new localities, geographic distribution, ecological characteristics, and comparisons with morphologically similar taxa were provided.
AtıfScopus3OpenAlex8İncele - MakaleYalnız künye2023Scopus SJRQ1Sustainability performance analysis of micro-mobility solutions in urban transportation with a novel IVFNN-Delphi-LOPCOW-CoCoSo framework
Ecer, Fatih; Küçükönder, Hande; Kayapınar Kaya, Sema; Faruk Görçün, Ömer
Almost all megacities worldwide are under pressure from environmental pollution and excessive resource usage due to rapid urbanization and increasing urban population. Within this scope, micro-mobility solutions (MMSs), an extension to the primary urban transportation network, have become even more critical recently. However, when we executed a preliminary investigation concerning MMSs' sustainability, we noted some critical theoretical and managerial gaps: (1) the number of studies assessing MMSs using decision-making approaches is excessively scarce, (2) no paper in the literature deals with the MMSs' sustainability performance, and (3) there are no commonly accepted criteria set to assess the sustainability of the MMSs in the literature. The current study aims to present a practical and robust decision-making framework that can overcome excessively complicated uncertainties to evaluate the sustainability performance of MMSs. Further, it suggests a novel methodological framework, i.e., Delphi, Logarithmic Percentage Change-Driven Objective Weighting (LOPCOW), and Combined Compromise Solution (CoCoSo) methods with interval-valued fuzzy neutrosophic number (IVFNN) information, which can be defined as a reconciliation tool to set the criteria affecting the assessment processes. Findings present that computing time, scenic adoption, and accidents are the foremost criteria, whereas mini-electric VH, powered standing scooter, and powered seated scooter are the most promising MMSs, respectively. Findings reveal that computing time, scenic adoption, and accidents are the critical factors for the sustainability assessment of MMSs, whereas mini-electric VH, powered standing scooter, and powered seated scooter are the most promising MMSs, respectively. The current paper's overall outcomes and findings can assist practitioners and policy-makers in the urban transportation industry in setting sustainability policies and investing in the more rational and sustainable MMSs.
AtıfScopus104WoS91OpenAlex112İncele - MakaleYalnız künye2023Scopus SJRQ1Carbide slag recycling to fabricate shape-stable phase change composites for thermal energy storage
Xiong, Yaxuan; Wang, Huixiang; Ren, Jing; Nevzat, Akkurt; Xu, Qian; Nie, Binjian; Li, Chuan; Ding, Yulong
The mining and processing of traditional skeleton materials inevitably generates carbon emissions and pollutes the surrounding environment. To make full use of industrial solid waste, this work innovatively used carbide slag as skeleton material and Na2CO3 as phase change material (PCM) to fabricate shape-stable phase change composites (SSPCCs) via the cold-compression & hot-sintering method. Seven SSPCCs were fabricated with different mass ratios of carbide slag to Na2CO3. Then, the thermal energy storage (TES) performance, mechanical property, micromorphology, chemical compatibility as well as thermal cycling stability were investigated. The results showed that the carbide slag could combine with Na2CO3 to fabricate SSPCCs; Sample CN5 achieved the optimal performance with the mass ratio 52.5:47.5 of carbide slag to Na2CO3; Sample CN5 achieved a TES density of 993 J/g in the range of 100 to 900 °C, a compressive strength of 22.02 MPa and a maximal thermal conductivity of 0.62 W/(m·K); Both carbide slag and Na2CO3 were distributed uniformly in sample CN5, while good thermal stability after the 100 heating/cooling cycles and good chemical compatibility between the carbide slag components and the Na2CO3 were observed.
AtıfScopus34OpenAlex30İncele - MakaleYalnız künye2023Scopus SJRQ2Contribution of Mechanical Activation for Obtaining Potassium Chloride from Microcline
Alyosif, Bahaa; Uysal, Turan; Aydemir, Muhammet Kürşat; Erdemoğlu, Murat
The effect of intensive milling on the conversion of microcline (KAlSi3O8) to potassium chloride (KCl) occurred during the chlorination roasting process for artificial KCl production was investigated. A feldspar ore with 10.89% K2O grade and containing microcline was dry milled by a planetary ball mill for mechanical activation. Milled ore mixed with calcium chloride was roasted at temperatures between 500 and 1000 °C to get the chlorination roasting process. The product was then leached in water to dissolve KCl occurring during the roasting, which will be precipitated from the pregnant leach solution by evaporation. Results showed that potassium recovery from the unmilled ore increased rapidly up to 800 °C, and dramatically decreased at higher temperatures due to the removal of KCl from the furnace by means of evaporation. A potassium recovery of 31.95% was achieved by the unmilled ore, whereas it was 88.43% when 15 min milled ore was roasted at 750 °C. It was concluded that intensive milling caused mechanical activation of microcline to reduce the roasting temperature of the chlorination roasting process.
AtıfScopus12WoS11OpenAlex10İncele - MakaleYalnız künye2023Scopus SJRQ1The relationship between unemployment anxiety, job satisfaction and migration attitude among the next generation of Turkish nurses: A cross-sectional study
Öncü, Emine; Köksoy Vayısoğlu, Sümbüle; Karadağ, Gülendam; Şahin Orak, Nuray; Selçuk Tosun, Alime; Yüksekol, Özlem Doğan; Çatıker, Aslıhan; Yalçın, Gülcan Çiftçioğlu
Background: The global nursing shortage is complex and multifaceted. Despite the policy of increasing the number of nurses, concerns about the sustainability of the nursing workforce in Turkey continue. Aim: To evaluate the relationship between unemployment anxiety, job satisfaction, and migration attitudes among Turkish nursing candidates. Methods: A cross-sectional study was conducted with 1100 nursing candidates between April and June 2022. The data gathered from the “Personal Form, Job Satisfaction, and Brain Drain Attitudes Scale” were analyzed using logistic regression and decision tree analysis. Results: Of the participants, 67.1% were female, and the mean age was 22.6 ± 1.7 years. Being male (OR = 1.317, 95% Cl 0.994–1.743) having a low income (OR = 1.754, 95% Cl 1.334–2.306), feeling insecure about the future (OR = 2.340, 95% Cl 1.312–4.175), expecting a lower wage than desired (OR = 2.015, 95% Cl 1.132–3.586), and employment precariousness (OR = 1.786, 95% Cl 1.355–2.353) increase the possibility of experiencing high unemployment anxiety. On the other hand, family support for living abroad (OR = 0.579, 95% CI 0.408–0.821) and job satisfaction (OR = 0.799, 95% CI 0.692–0.921) decrease unemployment anxiety (p < 0.05). According to the results of the decision tree analysis, the host country's pull factors are the best predictors of the nursing candidates' intention to work abroad as nurses (p < 0.05). Conclusion: The increasing prevalence of unemployment anxiety and migration tendencies among nursing candidates requires the evaluation of policies aimed at increasing the number of nursing graduates in Turkey.
AtıfScopus9OpenAlex16
İncele - MakaleAçık Erişim2023Scopus SJRQ1A Multi-Input Convolutional Neural Networks Model for Earthquake Precursor Detection Based on Ionospheric Total Electron Content
Uyanık, Hakan; Şentürk, Erman; Akpınar, Muhammed Halil; Ozcelik, Salih T. A.; Kokum, Mehmet; Freeshah, Mohamed; Sengur, Abdulkadir
Earthquakes occur all around the world, causing varying degrees of damage and destruction. Earthquakes are by their very nature a sudden phenomenon and predicting them with a precise time range is difficult. Some phenomena may be indicators of physical conditions favorable for large earthquakes (e.g., the ionospheric Total Electron Content (TEC)). The TEC is an important parameter used to detect pre-earthquake changes by measuring ionospheric disturbances and space weather indices, such as the global geomagnetic index (Kp), the storm duration distribution (Dst), the sunspot number (R), the geomagnetic storm index (Ap-index), the solar wind speed (Vsw), and the solar activity index (F10.7), have also been used to detect pre-earthquake ionospheric changes. In this study, the feasibility of the 6th-day earthquake prediction by the deep neural network technique using the previous five consecutive days is investigated. For this purpose, a two-staged approach is developed. In the first stage, various preprocessing steps, namely TEC signal improvement and time-frequency representation-based TEC image construction, are performed. In the second stage, a multi-input convolutional neural network (CNN) model is designed and trained in an end-to-end fashion. This multi-input CNN model has a total of six inputs, and five of the inputs are designed as 2D and the sixth is a 1D vector. The 2D inputs to the multi-input CNN model are TEC images and the vector input is concatenated space weather indices. The network branches with the 2D inputs contain convolution, batch normalization, and Rectified Linear Unit (ReLU) activation layers, and the branch with the 1D input contains a ReLU activation layer. The ReLU activation outputs of all the branches are flattened and then concatenated. And the classification is performed via fully connected, softmax, and classification layers, respectively. In the experimental work, earthquakes with a magnitude of Mw5.0 and above that occurred in Turkey between 2012 and 2019 are used as the dataset. The TEC data were recorded by the Turkey National Permanent GNSS Network-Active (TNPGN-Active) Global Navigation Satellite System (GNSS) stations. The TEC data five days before the earthquake were marked as “precursor days” and the TEC data five days after the earthquake were marked as “normal days”. In total, 75% of the dataset is used to train the proposed method and 25% of the dataset is used for testing. The classification accuracy, sensitivity, specificity, and F1-score values are obtained for performance evaluations. The results are promising, and an 89.31% classification accuracy is obtained.
AtıfScopus27OpenAlex19İncele - MakaleAçık Erişim2023Scopus SJRQ1Greening Industrially Applied Toxic Cadmium Plating with γ-Ni2Zn11 Alloy in Deep Eutectic Solvents: Promising Electroplating Efficiency and Chemical Corrosion Resistance
Cihangir, Salih
Cadmium is an industrially applied plating metal used in aerospace applications, but electrodeposition of cadmium is toxic, and current production method will soon be banned. Therefore, electrodeposition of alternative alloys in environmentally friendly solutions is an attractive research area. An additive-free, nonaqueous, deep eutectic solvent (DES) containing Ni and Zn halide salts is developed in a greener environmental method. Gamma-phase nanocrystalline Ni2Zn11 is coated onto hot-rolled mild steel via pulse reverse current (PRC) in the developed nonaqueous solvent. The employed DES’ relatively low viscosity and sufficient conductivity enable the simultaneous reduction of Ni2+ and Zn2+ cations on microelectrode. Electrochemical quartz crystal microbalance (eQCM) analysis proves the absence of the commonly reported problem of electrode blocking during electrodeposition, revealing an efficiency of 86.07%. Appropriate PRC parameters are applied for scaled macroelectrode deposition. The plating profile exhibits 20 μm-thick alloy deposition without cracks around 3 h. Scanning electron microscopy–electron-dispersive spectroscopy and X-ray diffraction analyses reveal that 15.5 wt% Ni is in the nanograin phase, and all crystal planes belong to the γ-Ni2Zn11 phase, which is needed as an alternative to cadmium plating. Hardness and corrosion tests performed on the γ-Ni2Zn11 coating reveal better hardness and corrosion resistance with supporting morphological evidence.
AtıfScopus14WoS13OpenAlex16İncele - MakaleYalnız künye2023Scopus SJRQ2Genotoxic effect of iron oxide (Fe2O3) nanoparticles on Triticum aestivum (wheat)
Tasar, Neslihan
Industrial activities and unconscious consumption of natural resources cause environmental pollution with the rapid increase in the world population. As a result of the widespread use of iron oxide nanoparticles (Fe2O3 NP) with nano-industrial activities, it is predicted that this NP will accumulate in the air, water, and soil. In the present study, the purpose was to find out the genotoxic effects on root meristem cells of the Triticum aestivum L. plant, which is an indicator organism exposed to 20–40 nm Fe2O3 NPs at different concentrations (100, 200, and 400 ppm). The amount of Fe2O3 NP accumulated in T. aestivum used in the study was determined with x-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM), SEM element map, and EDS characteristic spectrum. All concentrations of Fe2O3 NP caused significant decreases in the mitotic index. Fe2O3 NPs significantly increased the frequency of mitotic abnormalities in T. aestivum root tip cells at all treatment times and all concentrations when compared to the control. Fe2O3 NPs were formed by various mitotic abnormalities such as loss of genetic material, deconstructed prophase, adhesion, chromosome groupings in metaphase, deconstructed metaphase, C-Metaphase, chromosomal loss, chromosomal fracture, polyploidy, deconstructed anaphase, lagging chromosome, fragment, polar deviation, bridging, propagation, asynchronous division, star anaphase, multipolarity, and deconstructed telophase. All these results show that Fe2O3 NPs are genotoxic and clastogenic and may also cause DNA damage. Briefly, these data show that Fe2O3 NPs taken by organisms may pose a danger to the organism and the upper consumer. These findings also show that the production and use of Fe2O3 NPs, which affect organisms, must be controlled, and ultimately, be safely disposed of to reduce their bioaccumulation. Research Highlights: In the present study, the purpose was to find out the genotoxic effects on root meristem cells of the Triticum aestivum L. (bread wheat) plant, which is an indicator organism exposed to 20–40 nm Fe2O3 NPs at different concentrations (100, 200, and 400 ppm). The amount of Fe2O3 NP accumulated in T. aestivum used in the study was determined with x-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM), SEM element map, and EDS characteristic spectrum. The mitotic index was calculated to reveal the genotoxic effect. “Loss of genetic material, deconstructed prophase, adhesion, chromosome groupings in metaphase, deconstructed metaphase, C-Metaphase, chromosomal loss, chromosomal fracture, polyploidy, deconstructed anaphase, lagging chromosome, fragment, polar deviation, bridging, propagation, asynchronous division, star Chromosomal abnormalities such as anaphase, multipolarity, and deconstructed telophase” were visualized. Fe2O3 NPs are genotoxic and clastogenic and may also cause DNA damage.
AtıfScopus10WoS7OpenAlex11İncele - MakaleYalnız künye2023Scopus SJRQ1Buoyancy-driven flow and thermal activity of nano-enhanced phase change material in inversed U-shaped chamber
Younis, Obai; Abderrahmane, Aissa; Laidoudi, Houssem; Akkurt, Nevzat; Fadhl, Bandar M.; Guedri, Kamel
This work aims to contribute to the positive evolution towards a green world and green energy by studying the natural convection of Nano-Enhanced Phase Change Material NEPCM in an inverted U-shaped cavity. The side walls of the cavity are kept at a cold temperature, while the upper corrugated wall and the lower wall are insulated with the expectation of the hot square body. The governing equations were solved numerically using the Galerkin finite element method (GFEM). The effects of the following factors on the heat transfer rate are presented and discussed: Rayleigh number (Ra = 103–106), number of ripples of the upper wall (N = 1–4), position of the square body (left, centre, and right), volume fraction of nanoparticles (ϕ = 0–0.08), and magnetic field strength (Ha = 0–100). It was found that the effect of N on the heat transfer rate was insignificant, while increasing ϕ reduced the heat transfer rate. In addition, placing the square body near the cold sidewalls (left or right position) improved the averaged Nusselt number (Nuavg), especially at low values of Ra. At the highest Ra studied, increasing Ha reduced the Nuavg by 15 %.
AtıfScopus11OpenAlex9İncele - MakaleYalnız künye2023Scopus SJRQ1The structure, optical basicity, ligand field strength and shielding parameters of alkali/alkaline borate glasses doped with V2O5
Sayyed, M.I.; Abdel-Ghany, A.M.; Askin, A.; Sedqy, E.M.; Sadeq, M.S.
In this work, we study the structural, optical and radiation shielding properties of Na2O–CaO-borate glass doped with different amounts of V2O5. A glass system with the composition (10.5CaO+ 16.5Na2O+ (73-x)B2O3+ xV2O5; where x = 0, 2.5, 5 and 10.5 mol%) was produced following the melt quenching technique. The molar volume and density of glasses both increase with the increase in V2O5:B2O3 ratios. Moreover, the average ligand field strength reduced from 2.32 to 2.15 × 1016 cm2 with the increase in V2O5:B2O3 ratios, which correlates with the increased values of molar volume and interatomic separations. Furthermore, the optical basicity of the glass samples increased from 0.601 to 0.666 with increasing V2O5:B2O3 ratios. The optical absorption spectra are studied for further investigation of the optical features. To extract the absorption edge and the absorption bands, a deconvolution process was applied to the absorption spectra. The obtained bands from this deconvolution process confirmed the presence of vanadium in its oxidation states V3+, V4+ and V5+. Furthermore, more additions of V2O5 produced an obvious reduction in Eg values from 3.69 to 3.08 eV along with a redshift in the fundamental absorption edges. These results were attributed to the further creation of nonbridging oxygens within the glass matrix. Furthermore, the addition of V2O5 rather than B2O3 enhances the radiation shielding parameters. Accordingly, the CaNaBV10.5 glass sample is the best attenuator among the fabricated CaO–Na2O–B2O3–V2O5 glasses due to the highest mass attenuation coefficient and lowest half-value layer. Moreover, the half-value layer values of the present glasses were compared to some common materials in the radiation shielding field. From this comparison, we concluded that all glass samples are better than commercial glass windows and ordinary concrete.
AtıfScopus19OpenAlex21İncele - MakaleYalnız künye2023Scopus SJRQ1Heat loss optimization and economic evaluation of a new fourth generation district heating triple pipe system
Chen, Xingli; Ren, Ling; Zheng, Qiang; Yang, Gang; Akkurt, Nevzat; Liu, Lin; Liu, Zhiwei; Qiang, Yujie; Yang, Huachao; Xu, Qian
In response to the heat loss caused by the temperature difference between the heating pipes and external environment during the pipe transportation, heat contradiction between the total heat loss of the piping system and heat transfer between tubes, as well as economic balance between the cost of heat loss and cost of material loss. Based on TOTS (Two-supply/One-return, triple pipe structure) heat loss theory of the fourth-generation district heating system, this paper optimizes structure of pipes by setting dimensionless characteristic parameters θ and β. Finally, a mathematical model is proposed to calculate economic efficiency of pipeline network by considering the cost of initial construction material loss and operation heat loss of the pipe. Results show that, from energy perspective, comprehensive heat as system energy consumption evaluation index is positively correlated with θ, decreases first and then increases as β increases. Total heat loss of system dominates comprehensive heat. Lowest comprehensive heat of system is 18.12 w/m for θ of 0.1945 and β of 0.0739. From economic perspective, total system loss cost as system economic evaluation index is positively correlated with both θ and β. Total system heat loss cost dominates total system loss cost. Lowest total system loss cost is $29.39/m for θ of 0.1945 and β of 0.0509.
AtıfScopus16OpenAlex20İncele