Sürdürülebilir Kalkınma Amaçları

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  • MakaleAçık Erişim2023Scopus SJRQ2
    ZrN and ta-C coatings on titanium for biomedical applications: Improved adhesion, corrosion, antibacterial activity, and cytotoxicity properties

    Aslan, Naim; Aksakal, Bünyamin; Cihangir, Salih; Cetin, Fadime; Yilmazer, Yasemin

    Commercially pure titanium (CP-Ti) is extensively used in biomedical applications. However, numerous qualities, including mechanical strength, corrosion resistance, and wear resistance, must be established for long-term performance as an implant material. This study investigates the enhancement of surface properties of CP-Ti through physical vapor deposition (PVD) with ZrN and ta-C (tetrahedral amorphous carbon). Among the coatings, ZrN revealed best overall results, such as adhesion, corrosion, microhardness, and wettability, excluding cell viability when compared to ta-C. E. coli and S. aureus were employed for antibacterial activity and MTS cell viability experiments. Compared to α-titanium, hardness tests revealed 91% increase in ZrN coating, and %22 increase in ta-C coating. Super-hydrophobicity and excellent antibacterial activity were found for ZrN coatings in comparison to ta-C. These findings emphasize the potential of ZrN and ta-C coatings to improve the surface properties of titanium, encouraging it to be used in biomedical devices. Graphical abstract: [Figure not available: see fulltext.].

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus16WoS16OpenAlex19
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  • MakaleAçık Erişim2023Scopus SJRQ2
    Investigation of fundamental electrical and optoelectronic properties of an organic- and carbon-based MnPc/GC photodiode with high photosensitivity

    Aktas, Sitki; Unal, Fatih; Kurt, Mustafa Sukru; Koç, Mümin Mehmet; Arslan, Tayfun; Aslan, Naim; Coşkun, Burhan

    The aim of this work is to provide an alternative to optoelectronic devices that use carbon and organic materials. To achieve this, we coated a modified MnPc organic semiconductor compound onto a graphite-like carbon (GC) thin film using the thermal evaporation technique, and fabricated an organic-based, highly light-sensitive MnPc/GC hybrid heterojunction. The heterojunction had a transmittance of approximately 60% in the visible region, an absorption coefficient of ∼106 m−1, and an energy band gap of 2.6 eV. Subsequently, Ag contacts were grown on the surface of each layer, and the Ag/MnPc/GC/Ag photodiode was subjected to fundamental electrical analysis at various light intensities and a ±3 V applied potential. Analysis in a dark environment revealed that the photodiode had a rectification ratio of 2.59 × 103, a series resistance of 28 Ω, and a shunt resistance of 4.17 × 104 Ω, as calculated from Ohm’s law. The diode ideality factor and barrier height of the photodiode were determined from thermionic emission theory to be 5.60 and 0.71 eV, respectively, and it was observed that these decreased with increasing light intensity. The photodetector parameters of the MnPc/GC hybrid photodiode were determined under positive and negative applied potentials at various light intensities. The highest photocurrent, photoconductive responsivity, photosensitivity, and specific detectivity were determined to be 1.512 × 10−1 A, 11.52 A.W−1, 9.83 × 105, and 2.48 × 1012 Jones, respectively, which were significantly higher than those reported in literature for organic and inorganic-based photodiodes. Based on the findings, it was concluded that the Ag/MnPc/GC/Ag photodiode holds promise as an alternative for sensors, solar cells, photodetectors, and optoelectronic communications applications.

    AtıfScopus10WoS9OpenAlex14
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  • MakaleYalnız künye2023Scopus SJRQ2
    Energy-momentum localization in rainbow gravity

    Korunur, Murat; Korunur, Sibel

    Theoretical physicists generally prefer to modify the general theory of relativity rather than avoiding the successful approaches that have been offered to us. Hence, the rainbow formalism of gravity, which is one of the most studied quantum gravity candidates in literature, has recently gained importance in the field. In this study, the energy-momentum localization problem is discussed for the Taub universe within the framework of rainbow gravity. To achieve this goal, energy and momentum components are calculated by making use of diverse values of rainbow functions in the Einstein, Bergmann-Thomson, Landau-Lifshitz, and the Papapetrou prescriptions for the geometry under consideration. Except for the Landau-Lifshitz prescription, all prescriptions depend on the rainbow functions and the momentum components vanish. Graphical analysis is performed for all the energies obtained. Also, it is shown in limiting condition f1(x) → 1; f2(x) → 1 that the results are compatible with the ones obtained in the general relativity.

    AtıfOpenAlex1
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  • MakaleYalnız künye2023Scopus SJRQ1
    Ultrasound assisted adsorptive removal of Cd+2 ions from the water system using Bi2S3 nano/micro flowers

    Kurnaz Yetim, N.; Aslan, N.; Özcan, C.; Koç, M.M.

    Heavy metal ions threaten public health and marine life; thus, removal of heavy metals is essential for the environment. Bi2S3 nanostructures are active materials which used in various applications. In this work, we produced Bi2S3 nanoflowers using hydrothermal synthesis and assessed their Cd2+ ions removal capability. Structural properties of the Bi2S3 nanoflowers were assessed by various like scanning electron microscopy, X-ray diffraction. Chemical characteristics of the materials were confirmed using energy dispersive X-ray spectra. Different parameters affecting the Cd2+ ion recovery was worked some of which are adsorbent amount, Cd2+ ion concentration, pH, adsorbent time, eluent type and amount, etc. For cadmium, the optimum pH was determined 8.0 for 1 M HNO3 eluent. Optimum adsorbent amount was determined as 150 mg while optimum recovery duration was found as 30 min. Bi2S3 nanoparticles managed to achieve 99.3% Cd2+ recovery rate in 5 mL eluent volume, for optimum condition. The adsorption capacity of the Bi2S3 nanoflowers was found to be promising and therefore, it was illustrated that Bi2S3 nanoflowers are good candidates as sorbent for water remediation applications.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus3WoS3OpenAlex3
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  • MakaleAçık Erişim2023Scopus SJRQ2
    Application of the deep transfer learning framework for hydatid cyst classification using CT images

    Gul, Yeliz; Muezzinoglu, Taha; Kilicarslan, Gulhan; Dogan, Sengul; Tuncer, Turker

    Hydatid cyst, which causes important public health problems, is a disease frequently reported by radiologists. Classification of hydatid cyst types is very important to give the most suitable cure to patients. In order to decrease the misclassification rates of these cysts, machine learning is a good solution to create intelligent medical assistants. The primary objective of this work is to develop a new image classification framework to classify hydatid cyst types. Firstly, we collected a computed tomography (CT) image dataset. This CT image dataset consists of 2416 CT images with five classes (hydatid cyst types). We proposed a new deep feature engineering dataset framework for this dataset. This framework consists of (i) deep feature extraction by deploying transfer learning, (ii) iterative feature selection using INCA (iterative neighborhood component analysis), and (iii) classification. In the first phase—the feature extraction phase—we extracted deep features by deploying ten pretrained convolutional neural networks (CNNs). The used CNNs are commonly used CNNs, and the deep features have been extracted using the last pooling and fully connected layers of these networks. INCA has been applied to the generated deep features by each feature vector. k-nearest neighbors (kNN) classifier has been utilized to generate predicted values of these 10 CNNs using the selected features by INCA. Our proposed INCA-based deep feature extractor attained over 92% classification accuracy for each pretrained model. Our proposed framework reached over 92% classification accuracies, clearly demonstrating that our proposed framework is good image classification.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus10WoS5OpenAlex8
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2023Scopus SJRQ1
    The Effects of Changing the Effective Crest Length of Labyrinth Side Weir on Discharge Capacity

    Dogan, Yusuf; Kaya, Nihat

    Labyrinth side weirs have significant advantages according to conventional side weirs in terms of discharge capacity. Labyrinth side weirs are especially advantageous in places where more discharge is required from small weir openings lengths. The most significant feature of labyrinth side weirs is their effective crest length, which enables them to discharge more flow. In this study, the situation where the discharge capacity is decreased due to the narrowing of the crest length of the labyrinth side weir for any reason was experimentally investigated in detail. It was also considered that the potential narrowing could be in the upstream weir crest length. The overflow from the remaining length of the crest was enabled by the 1/3, 2/3, and 3/3 closure of the upstream crest length of the labyrinth side weir. Therefore, it was attempted to determine the decrease in discharge capacity due to the narrowing in the effective crest length. The values of the discharge coefficient were obtained by using the De Marchi approach. The study was conducted for subcritical flow regimes and steady-state flow conditions. A total of 980 experimental runs were conducted in this study. As the length of upstream effective crest length of the triangular labyrinth side weir at the straight channel decreases, the discharge coefficient also decreases. By narrowing the length of effective upstream crest length in 1/3, 2/3, and 3/3 ratios, the total discharge capacity decreased by approximately 10%, 23%, and 48%, respectively.

    AtıfScopus7WoS6OpenAlex6
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  • MakaleYalnız künye2023Scopus SJRQ2
    Deep learning based an effective hybrid model for water quality assessment

    Utku, Anıl; Utku, Esen Damla; Kutlu, Banu

    Water, which is very important for life and civilizations on Earth, has been a source of life for all living things. However, freshwater resources gradually decrease due to climate change, pollution, and population growth. Water pollution is the quality changes that occur due to various activities of people, change the chemical, biological, and physical properties of water, restrict or prevent its use, and disrupt ecological balances. The water quality criteria determined to keep this pollution under control ensure the safe use of water. Water quality observations have gained more importance today due to intense environmental concerns and water pollution. This situation revealed the necessity of water quality assessment for water source use. In this study, the CNN-LSTM-based hybrid model was proposed to assess water quality. The proposed model was compared with AdaBoost, DT, GNB, kNN, LGBM, RF, and LSTM according to accuracy, precision, recall, F-score, and AUC. The proposed model has 98.81% accuracy, 99.03% precision, 99.65% recall, 99.33% F-score, and 93% AUC. Practitioner Points: CNN-LSTM hybrid model was developed to water quality assessment. The proposed model is compared with established techniques like AdaBoost, DT, GNB, kNN, LGBM, RF, and LSTM. The developed model has 98.81% classification accuracy. Experimental results show that the developed model will ensure the use of safe water according to water quality criteria.

    • SDG 6 · Temiz Su ve Sanitasyon
    AtıfScopus7WoS4OpenAlex8
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2023Scopus SJRQ2
    The Effect of Using Ferro-Alloy on the Properties of AlCoFeNiMoTi High-Entropy Alloy Produced by Arc-Melting Method: Design of Low Cost

    Güler, Seval H.

    The cost of high-entropy alloys (HEAs) is one of the most major obstacles to their widespread use. The cost of these alloys with significant amounts of five metals might reach very high levels depending on the type and quantity of metal utilised. Therefore, this study examined the effect of the use of ferro-alloys as part of the charge mixture on the properties of AlCoFeNiMoTi alloy. Ferro-alloys are much less expensive than the pure form of the same metal. To that end, two groups of samples were produced. The AlCoFeNiMoTi alloy was produced using high-purity metals as the metallic charge in the first group of samples. Instead of utilising the pure forms of some expensive metals that make up such alloy, as the metallic charge, lower-cost ferro-alloy forms were employed in the second group of samples. Following the preparation of the appropriate compositions, alloys were produced using the arc-melting method, and the produced alloys were subject to homogenization heat treatment. The obtained samples were characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Then, mechanical and corrosion tests were run. The corrosion resistance of the HEAs was compared with an electrochemical polarisation technique in a 3.5% NaCl electrolyte. It was observed that many intermetallics precipitated through the heat treatment of the samples, and the precipitates negatively affected the mechanical properties of the alloy. Also, in the samples in which ferro-alloy was used instead of pure metal, the mechanical properties were substantially degraded. This is believed to be associated with the presence of inclusions and other residues in ferro-alloys. Graphical Abstract: [Figure not available: see fulltext.]

    AtıfScopus6WoS7OpenAlex7
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  • MakaleYalnız künye2023Scopus SJRQ4
    Neurotoxic Effect of New Generation Insecticide with Flubendiamide Active Ingredient in Gammarus pulex (Linnaeus, 1758) (Amphipoda: Gammaridae) at Different Temperatures

    Söylemez, Hilal; Serdar, Osman

    This study aimed to determine the relationship between temperature and neurotoxicity of a new generation insecticide, the active ingredient of which is flubendiamide, on non-target aquatic organisms (Gammarus pulex (L., 1758)). Firstly, LC50 values of flubendiamide on G. pulex were determined at 16, 18 and 20 °C as 256.83 ± 19.59 µgL-1, 169.38 ± 34.17 µgL-1 and 155.84 ± 17.22 µgL-1, respectively. We found that the acute toxicity sensitivity of the test organism to the pesticide containing flubendiamide increased with increasing temperature. Secondly, G. pulex was exposed to non-lethal concentrations of flubendiamide pesticide for 96 hours at the above temperatures. Finally, the changes in acetylcholinesterase (AChE) enzyme activity were determined for each temperature using ELISA kits. The exposure time between the 24th and 96th h at the same temperature was found to be statistically insignificant (p>0.05). It was determined that the inhibition value of AChE enzyme activity on the test organism of the pesticide with active ingredient flubendiamide increased depending on the temperature increase. Considering the changes in AChE enzyme activities in G. pulex at different temperatures against flubendiamide insecticide, it was concluded that it can be used as a useful biomarker.

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