Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Güler, Ömer(8)
- Özkul, İskender(7)
- Aslan, Naim(6)
- Aksakal, B.(5)
- Artuğer, Fırat(5)
- Aslan, N.(5)
- Kahraman, Gökhan(5)
- Say, Yakup(5)
- Tekin, H.O.(5)
- Canbay, Canan Aksu(4)
- Danabas, Durali(4)
- Dikici, B.(4)
- Gul, Muhammet(4)
- Ince, Muharrem(4)
- Kaplan Ince, Olcay(4)
- Karaduman, Oktay(4)
- Koç, Mümin Mehmet(4)
- Kutlu, Banu(4)
- Taşgın, Yahya(4)
- ALMisned, Ghada(3)
- Ates, Mehmet(3)
- Aşkin, A.(3)
- Baykal, Duygu Sen(3)
- Cihangir, Salih(3)
- Doğan, Fatih(3)
- Güler, Seval Hale(3)
- Imak, Andaç(3)
- Karaaslan Ayhan, Nagihan(3)
- Kök, Mediha(3)
- Topal, Murat(3)
- Torğut, Gülben(3)
- Yucesan, Melih(3)
- Özkaynak, Fatih(3)
- Akkurt, Nevzat(2)
- Aksoy, M.E.(2)
- Aksu, Onder(2)
- Alkarrani, Hessa(2)
- Alp Dal, Nursel(2)
- Arslan Topal, E. Işıl(2)
- Arslan, Zikri(2)
Yayınlar
- MakaleYalnız künye2024Scopus SJRQ2A Method for Designing Substitution Boxes Based on Chaos with High Nonlinearity
Artuğer, Fırat
Cryptography aims to design algorithms for the protection of important data transmitted over unsecured networks. These algorithms encrypt the data and render it incomprehensible even if it is captured by enemies. Today’s data encryption standard is the AES algorithm. The most important and nonlinear unit in the AES algorithm is the s-box structure. The S-box provides the mixing process in the algorithm, that is, the confusion. An s-box structure with a high nonlinearity value greatly increases the security against various attacks. Therefore, s-box is of vital importance in an encryption algorithm. When we look at the literature, chaos-based s-box structures are frequently used. However, the nonlinearity value of s-boxes produced with chaos is low. In this article, a new, fast, and very simple method is proposed to increase the nonlinearity value of chaos-based s-box structures. In the proposed method, the nonlinearity value is calculated by changing the places of the elements respectively. When the nonlinearity value increases, the s-box is updated, and the next element is passed. In this way, many iterations are not looked at in vain. This saves a lot of time. As a result of the analysis, it has been proven that the s-box structure obtained by the proposed method is cryptographically strong and has a high nonlinearity value. It is thought that the proposed method will provide many advantages for future cryptography applications.
AtıfScopus9WoS7OpenAlex8
İncele - MakaleYalnız künye2024Scopus SJRQ1Lanthanum-based magnetic biopolymers for brilliant green removal from aqueous solutions
Karaaslan Ayhan, Nagihan
In this study, lanthanum (La)-based magnetic biopolymers were synthesized, and the first adsorption study was conducted on the removal of brilliant green dye from aqueous water with these biopolymers. For the adsorption study, adsorption parameters were investigated and the ideal adsorption conditions determined for the removal of brilliant green dye from aqueous solutions are pH 11, t 60 min, m 10 mg, C0 25 mg/L, T 298 K. It was determined that the adsorption process was compatible with the single-layer Langmuir isotherm, and maximum adsorption capacity obtained according to the Langmuir isotherm was calculated as 256.41 mg/g. The adsorption process was found to be in accordance with the pseudo-second-order, and the adsorption process was explained by intra-particle diffusion. According to studies of adsorption thermodynamics, it has been established that the nature of the adsorption reaction is spontaneous, and this process is endothermic and has increasing randomness. Moreover, the reusability of magnetic lanthanum/alginate (La/Alg) biopolymers was investigated, and it was determined that the biopolymers could be used successfully. In summary, brilliant green dye has been successfully removed with simple, low-cost, environmentally friendly, and easily obtained magnetic La/Alg biopolymers. It can be stated that even low amounts of these biopolymers can be effective in the treatment of highly concentrated dye wastewaters.
AtıfScopus1OpenAlex1
İncele - MakaleAçık Erişim2024Scopus SJRQ2Development of new generation cakes fortified with zinc oxide nanoparticles
Kaplan Ince, Olcay; Aydogdu, Burcu; Ince, Muharrem
This study aimed to develop new generation cakes that were fortified with calcined ZnO nanoparticles (CZnO), uncalcined ZnO nanoparticles (UCZnO), beads (B(CZnO)) synthesized by encapsulating the CZnO with sodium alginate (SA), and the beads (B(UCZnO)) synthesized by encapsulating the UCZnO with sodium alginate (SA) and investigated the zinc (Zn) release in fortified cakes in simulated body fluids (SBF). The present study represents a novel method for increasing intestinal absorption and bioavailability of dietary zinc with zinc nanoparticles for use in the preparation of Zn fortified cakes as a dietary supplement to compensate for zinc deficiency in humans. The results revealed that a rapid increase in the release time and rate in the SGF solution was noted in the UCZnO added cakes. It was attributed to increased intestinal absorption and bioavailability as a result of the ultra-small size of ZnO. Also, ZnO release kinetics in SBF was also studied and data were adjusted into different kinetic models involving zero-order, first-order, Higuchi, and Korsmeyer–Peppas models. The present investigation recommends adding UCZnO to the cakes to control and increase the release from the cakes.
AtıfScopus3WoS2OpenAlex3İncele - MakaleYalnız künye2024Scopus SJRQ2Production of CoCrFeNi(Al/Ti) High-Entropy Alloys by Mechanical Alloying: Optimization of Milling Time and Comparison of Corrosion Susceptibilities
Say, Yakup; Dikici, Burak; Kaseem, Mosab; Özkul, İskender; Güler, Ömer
CoCrFeNi alloy is the most well-known four-component equiatomic alloy. In addition, it has a low-cost composition among HEAs. Four-component alloys are considered semi-HEAs. Therefore, a five-component HEA design was made by adding another metal to the main composition of CoCrFeNi. As the fifth metal, two metals such as Al and Ti, which are relatively low in cost and have the potential to improve properties, were chosen. For this purpose, in this study, the effect of Al and Ti on CoCrFeNi main alloy was investigated by producing three different samples as CoCrFeNi, CoCrFeNiAl, and CoCrFeNiTi. The alloys with three different compositions (used three different samples) were successfully produced by the mechanical alloying method. Although Al and Ti have the possibility of intermetallic with other metals in the alloy, such a formation was not observed during mechanical alloying, and it was observed that all metals were homogeneously distributed in the alloy. The microhardness results indicated that CoCrFeNiAl and CoCrFeNiTi samples had similar hardness values. While the hardness of the CoCrFeNi sample was 136 HV, the hardness of the CoCrFeNiAl sample was 262 HV. However, the hardness of the CoCrFeNiTi sample decreased significantly. The hardness of the CoCrFeNiTi sample was measured as 269 HV. It was observed that the addition of Ti and Al to the base alloy was increased a significant change in hardness. It has been observed that Ti supplementation has a more positive effect on improving corrosion properties. It is seen that the corrosion potentials shift toward more negative potentials with the addition of Al and Ti to the CoCrFeNi (−194 mV) alloy (−306 and −224 mV for CoCrFeNiAl and CoCrFeNiTi, respectively). When the surface morphologies of the alloys are compared after corrosion; the damage to the alloy surfaces increases due to the negative Ecorr value in CoCrFeNiAl and CoCrFeNiTi alloys compared to the master alloy. However, the high corrosion current density (12.69 µA/cm2) in the CoCrFeNiTi sample caused much more damage to this alloy. Graphical Abstract: (Figure presented.)
AtıfScopus14OpenAlex16İncele - MakaleAçık Erişim2024Scopus SJRQ1Enhanced photocatalytic abilities of innovative NbTaZrMoW high-entropy alloys (HEAs): a comparative analysis with its high entropy oxide (HEO) counterpart
Zakir, O.; Guler, O.; Idouhli, R.; Nayad, A.; Khadiri, M.E.; Guler, S.H.; Abouelfida, A.; Dikici, B.
The photocatalytic performance of high entropy alloy (HEA) and its oxide form (high entropy oxide, HEO) have been evaluated in this study. The HEA, composed of Nb, Ta, Zr, Mo, and W powders, was synthesized through a mechanical alloying process for 120 h. This process was carried out under a high-purity Ar atmosphere to prevent oxidation. Subsequently, the HEA was converted into HEO via a mechano-thermal oxidation method 900 °C for 12 h. The photocatalytic activity of both oxidized and non-oxidized samples was systematically evaluated by degradation of methyl blue (MB) under UV irradiation. Electron dispersive spectroscopy (EDS), X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) were used to investigate the structural and chemical features of the alloys. Furthermore, BET surface area analysis and Zeta potential measurements were conducted to understand the alloys’ surface properties and stability in aqueous solutions. The results showed that the HEA has a remarkable photodegradation performance of around 58.77% which is two times higher than that observed with the HEO. Graphical abstract: (Figure presented.)
AtıfScopus31WoS30OpenAlex28İncele - MakaleYalnız künye2024Scopus SJRQ1Optimization of Pectin Extraction from Lemon Peel Powder by Ohmic Heating Using Full Factorial Design
Çilingir, Seda; Duran, Gülseven; Gökyildiz, Beritan; Goksu, Ali; Sabanci, Serdal; Cevik, Mutlu
Ohmic heating-assisted extraction has emerged as an effective method preferred in recent years. This extraction method is affected by experimental factors such as temperature, process time, and voltage gradient. The present study aimed to optimize the pectin extraction process from lemon peel powder samples by the ohmic heating-assisted extraction method. In this study, the effects of 3 different voltage gradients (7, 9, and 11 V/cm), 3 different solid to liquid ratios (1:20 g/mL, 1:40 g/mL, and 1:60 g/mL), and 3 different holding times (0, 60, and 120 min) and their interactions were investigated to determine the optimum extraction condition at constant temperature (80 °C) and pH = 1 sulfuric acid solution. The factors examined in the optimization procedure were pectin yield, power consumption, and energy efficiency. The optimum conditions were found to be 11 V/cm voltage gradient, 1:60 g/mL solid to liquid ratio, and 120-min holding time with a desirability value of 0.778. The results of this study could give important information about the design of industrial scale ohmic heating units, especially from different food wastes in industrial pectin production.
AtıfScopus7WoS7OpenAlex5İncele - MakaleYalnız künye2023Scopus SJRQ3Thermal Device Beyond the Carnot Limit
Zengin, B.; Askin, M.; Salti, M.; Aydogdu, O.
Based on the Carnot cycle, we construct a theoretical heat engine working through the agency of the generalized polytropic gas. A heat engine described by using a thermodynamic equation-of-state defines a thermodynamical relation among state quantities such as internal energy U, volume V, entropy S, temperature T and heat capacity C. Investigating the thermal efficiency of the constructed heat engine shows that more efficient heat engine is obtained from the Carnot heat engine when the pressure of the working material takes certain values.
AtıfOpenAlex1İncele - MakaleAçık Erişim2023Scopus SJRQ1Effects of a Combination of Arginine Silicate Inositol Complex and a Novel Form of Biotin on Hair and Nail Growth in a Rodent Model
Demir, Betul; Cicek, Demet; Orhan, Cemal; Er, Besir; Erten, Fusun; Tuzcu, Mehmet; Ozercan, Ibrahim Hanifi; Sahin, Nurhan; Komorowski, James; Ojalvo, Sara Perez
The purpose of this study was to examine the effects of a combination of inositol-stabilized arginine silicate complex (ASI) and magnesium biotinate (MgB) on hair and nail growth in an animal model. Twenty-eight female Sprague–Dawley rats (8 weeks old) were randomized into one of the following groups: (i) group (control), shaved; (ii) group (ASI), shaved + ASI (4.14 mg/rat/day); (iii) group (ASI + MgB I), shaved + ASI (4.14 mg/rat/day) + MgB (48.7 μg/rat/day); and (iv) group (ASI + MgB II), shaved + ASI (4.14 mg/rat/day) + MgB (325 μg/rat/day). On day 42, compared with the control group, while hair density (p < 0.05, p < 0.01, and p < 0.0001, respectively) and anagen ratio (p < 0.01, p < 0.01, and p < 0.001) increased in the ASI, ASI + MgB I, and ASI + MgB II groups, telogen ratio decreased (p < 0.01, p < 0.01, and p < 0.001, respectively). In the molecular analysis, VEGF, HGF, and KGF-2 increased in the ASI (p < 0.01, p < 0.01, and p < 0.05, respectively), ASI + MgB I (p < 0.0001 for all), and ASI + MgB II (p < 0.0001 for all) groups when compared to the control group. FGF-2 (p < 0.01) and IGF-1 (p < 0.001) were found to be increased in the ASI + MgB I and ASI + MgB II groups. SIRT-1 and β-catenin increased in the ASI (p < 0.05 and p < 0.01), ASI + MgB I (p < 0.001 for both), and ASI + MgB II (p < 0.0001 for both) groups. Wnt-1 increased in the ASI + MgB I (p < 0.001) and ASI + MgB II (p < 0.0001) groups. In conclusion, the combination of ASI and MgB could promote hair growth by regulating IGF-1, FGF, KGF, HGF, VEGF, SIRT-1, Wnt, and β-catenin signal pathways. It was also established that ASI did not affect nail growth, whereas the MgB combination was effective using a higher dose of biotin.
AtıfScopus11WoS9OpenAlex11İncele - Kitap BölümüYalnız künye2023A Multi-parameter Occupational Safety Risk Assessment Model for Chemicals in the University Laboratories by an MCDM Sorting Method
Gul, Muhammet; Yucesan, Melih; Karacahan, Mehmet Kayra
University laboratories are high-risk working environments where many chemicals coexist to conduct teaching and scientific research. The frequent occurrence of such chemical-related occupational accidents in recent times highlights the importance of ensuring these units’ safety in universities for researchers, students, workplaces, and institutions. In occupational safety risk assessment, very few studies have grouped risks. Many of them also ignored some important risk parameters. Overcoming these disadvantages, this study developed a multi-parameter and multi-criteria decision-making (MCDM) sorting-based methodology for the occupational safety risk assessment of chemicals in a university laboratory. First, six different risk parameters (probability, severity, exposure, detectability, worsening factor, sensitivity to non-usage of personal protective equipment) were determined. The weight value was calculated using the best–worst method (BWM). Then, a risk priority value and classification for each chemical with TOPSIS-Sort, the MCDM sorting method. Finally, some control measures are recommended to reduce the safety risk of the laboratory. The applicability of the proposed methodology has been tested with a real case study. The methodology is intended to adapt to university laboratories’ risk assessment and become a primary reference for university safety analysts.
AtıfScopus2OpenAlex1İncele - MakaleYalnız künye2023Scopus SJRQ2A New S-box Generator Algorithm Based on 3D Chaotic Maps and Whale Optimization Algorithm
Artuğer, Fırat
Encryption provides security in cases such as storing confidential information or transmitting it over a network. Today, block cipher algorithms are generally used for encryption. Undoubtedly, one of the most important units of block cipher algorithms to ensure confidentiality is substitution box (s-box) structures. Because s-boxes are nonlinear structures, making the algorithm resistant to differential cryptanalysis. Therefore, the higher the nonlinearity value of the s-box, the stronger it will be. In this study, a new algorithm is proposed to generate s-boxes with high nonlinearity value. In the proposed algorithm, Lorenz and Chua systems, which are 3D chaotic maps, are used for the initial population. The s-boxes produced with these chaotic maps were then increased to 110.5 using the whale optimization algorithm (WOA). WOA is one of the important optimization algorithms developed in recent years and was used for the first time in s-box production in this study. Looking at the results of the analysis, the proposed method has outstripped most of the other existing studies, thanks to effective 3D chaotic maps and WOA.
AtıfScopus44WoS38OpenAlex45İncele - MakaleAçık Erişim2023Scopus SJRQ2Silver and Copper Coating Effects on Surface Morphology, Crystal Structure and Corrosion Behavior of NiTinol Shape Memory Alloy Plate
Say, Yakup; Kanca, Muhammed Sait; Kök, Mediha
NiTinol alloy has recently been in high demand in biomaterials applications due to its excellent superelasticity and shape memory properties. This demand has increased the studies on improving the negative properties of the NiTinol alloy, even if it is less. In this study, it was aimed to coat the nickel element in the NiTi alloy with biocompatible elements in order to prevent it from secreting its toxic effect after its implantation into the body. In accordance with this purpose, NiTi shape memory alloys were coated with silver and copper element by using thermal evaporation system, and the surface morphology of the alloys after coating was investigated by SEM–EDX (Scanning Electron microscope), and AFM (Atomic force Microscope). After the measurements, it was observed that the coating was successful and homogeneously distributed on the entire surface of the alloy. In addition, an important and positive result was that, the roughness value of the NiTi alloy was decreased with the coating. The change in the crystal structure of the uncoated and coated NiTi alloy was evaluated using an X-ray device, and it was observed that the silver and copper element peaks were formed along with the B2 phase, which is the main phase of the NiTi alloy. In order to examine the effect of coating on the biocompatibility of NiTi alloy, electrochemical test was performed by rapid measurement method in simulated body fluid and corrosion behavior was investigated. According to these experiments, it was concluded that silver plating is more successful in term of biocompatibility than copper coating.
AtıfScopus4WoS3OpenAlex4İncele - MakaleAçık Erişim2023Scopus SJRQ1Integrating stratified best–worst method and GIS for landslide susceptibility assessment: a case study in Erzurum province (Turkey)
Konurhan, Zekeriya; Yucesan, Melih; Gul, Muhammet
Landslides are among the most destructive geological disasters that seriously damage human life and infrastructures. Landslides mainly occur in mountainous regions around the world. One of the key processes to reduce these damages is to uncover landslide-exposed areas through different data-driven methods such as Geographical Information System (GIS) and multi-criteria decision-making (MCDM). In the literature, there are many studies developed with these fundamental tools. In this study, unlike the literature, a new landslide susceptibility assessment model is proposed by integrating GIS with the stratified best–worst method (S-BWM). This model has four main dimensions and 16 sub-dimensions under topography, environment-land, location, and hydrological factors, weighted with the S-BWM. A network was created considering the different states that may arise in the importance weights of these dimensions in the future. The transition probabilities of these states were predicted and injected into the classical BWM. Then, maps were created for these dimensions and classifications for each sub-dimension according to the map characteristics. Finally, the most susceptive landslide locations were determined with GIS-based calculations. To demonstrate the model’s applicability, a case study was conducted for the Erzurum region, one of Turkey’s landslide-prone regions. In addition, besides the landslide map, an analysis and discussion about the spatial distribution of susceptibility classes was presented, contributing to the study’s robustness. In the results of landslide susceptibility analysis, landslides are higher in the range of about 1600–2500 m. Approximately 42% (35.59 sq. km) of the study area has high landslide susceptibility, while 58% (64.41 sq. km) has medium and low landslide susceptibility.
AtıfScopus19WoS17OpenAlex18İncele - MakaleAçık Erişim2023Scopus SJRQ2ResMIBCU-Net: an encoder–decoder network with residual blocks, modified inverted residual block, and bi-directional ConvLSTM for impacted tooth segmentation in panoramic X-ray images
Imak, Andaç; Çelebi, Adalet; Polat, Onur; Türkoğlu, Muammer; Şengür, Abdulkadir
Objective: Impacted tooth is a common problem that can occur at any age, causing tooth decay, root resorption, and pain in the later stages. In recent years, major advances have been made in medical imaging segmentation using deep convolutional neural network-based networks. In this study, we report on the development of an artificial intelligence system for the automatic identification of impacted tooth from panoramic dental X-ray images. Methods: Among existing networks, in medical imaging segmentation, U-Net architectures are widely implemented. In this article, for dental X-ray image segmentation, blocks and convolutional block structures using inverted residual blocks are upgraded by taking advantage of U-Net’s network capacity-intensive connections. At the same time, we propose a method for jumping connections in which bi-directional convolution long short-term memory is used instead of a simple connection. Assessment of the proposed artificial intelligence model performance was evaluated with accuracy, F1-score, intersection over union, and recall. Results: In the proposed method, experimental results are obtained with 99.82% accuracy, 91.59% F1-score, 84.48% intersection over union, and 90.71% recall. Conclusion: Our findings show that our artificial intelligence system could help with future diagnostic support in clinical practice.
AtıfScopus21OpenAlex23İncele - MakaleAçık Erişim2023Scopus SJRQ2Shape Memory Polymer-Based Nanocomposites Magnetically Enhanced with Fe3O4 Nanoparticles
Pekdemir, Mustafa Ersin; Aydin, Derya; Selçuk Pekdemir, Sibel; Erecevit Sönmez, Pınar; Aksoy, Edanur
This work aimed to investigate the effect of magnetic Fe3O4 nanoparticles (MNP), which are known to have a wide range of applications in recent years, on nanocomposite films prepared with shape memory polymers. Herein, PLA–PEG blend nanocomposite films were prepared by solution casting method using MNP at different ratios. PLA–PEG Blend/MNP nanocomposite films were characterized with Attenuated total reflection infrared spectroscopy (ATR-IR) to determine the –C=O stretching of PLA and Fe–O stretching signals of Fe3O4. The thermal stability, morphology, and magnetic behavior were studied by comparing the results among PLA–PEG blend, PLA–PEG blend/MNP nanocomposite with thermogravimetric analyses (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and a vibrating sample magnetometer (VSM), respectively. The effect of MNP on the shape memory properties of PLA/PEG blend was investigated. Moreover, the comparison of antimicrobial activity between PLA/PEG blend and PLA–PEG blend/MNP nanocomposite films were conducted by the disk diffusion method. The results showed that MNP increased the thermal stability of the PLA/PEG blend and the nanocomposites inhibited the growth of C.albicans microorganism. Graphical Abstract: [Figure not available: see fulltext.].
AtıfScopus41WoS39OpenAlex42İncele - MakaleYalnız künye2023Scopus SJRQ2Silver-Doped Diamond-Like Carbon (DLC:Ag) Nanocomposite Films for Solar Tracking Applications
Aslan, Naim; Kurt, Mustafa Şükrü; Koç, Mümin Mehmet
Diamond-like carbon (DLC) films are often investigated for their mechanical properties. In this report, we assessed the electrical and photovoltaic characteristics of DLC:Ag composite films produced for solar tracking and/or photodetector device purposes. We used the magnetron sputtering technique to prepare DLC:Ag thin films where DLC and Ag were co-deposited on Si wafers. Structural characterization of the thin films was performed using AFM, EDX, and Raman spectroscopy. Current–voltage, capacitance–voltage and conductance–voltage characterizations were employed to assess the electrical characteristics and photovoltaic characteristics of the DLC:Ag thin films. I–V characteristics were characterized under various illumination intensities to assess the effect of light intensity on the DLC:Ag composite films. We found that silver-doped DLC composite thin films are responsive to light and exhibit detector-like behaviour. Barrier height was found to be between 0.55 eV and 0.81 eV while the ideality factor was calculated to be between 1.94 and 7.11. It was found that photovoltaic and diode properties were affected by applied illumination intensities. C–V characteristics indicated that the electrical properties of the thin films are responsive to the signal frequency. The density of interface states was calculated which was thought to be a factor related to this behaviour.
AtıfScopus17WoS16OpenAlex14İncele - MakaleYalnız künye2023Scopus SJRQ2Replacement of Cu with One-Step Production of CuAg (Ag0.04Cu3.96): Superior Conductivity, Corrosion Resistance, and Hardness
Cihangir, Salih
Copper is the forefront of the fundamental metals used in various industries. It is utilized as bulk or electrodeposited on PCBs or interconnects. However, poor corrosion resistance and hardness reduce copper performance and limit its applicability in the fields that require mechanical strength, such as probing applications. Facile electrochemical deposition of Cu(Ag) films was examined in a deep eutectic solvent known for its green nature. SEM–EDS technique was applied for morphostructural and crsytal plane analysis. XRD analysis revealed Cu3.96Ag0.04 phase, and 2% Ag was identified in the Cu(Ag) film in EDS. Four-prope point resistivity analysis was performed via galvano-impedance spectroscopy. Obtained resistivity value of 5 µm thick Cu(Ag) coating was lower than the compliance limit of International Technology Roadmap for Semiconductors. Corrosion analysis was carried out via electrochemical impedance spectroscopy technique, and Cu(Ag) films demonstrated better resistance. Hardness tests also revealed that Cu(Ag) was approximately two times harder than Cu. Graphical Abstract: [Figure not available: see fulltext.]
AtıfScopus6WoS6OpenAlex6İncele - MakaleAçık Erişim2022Scopus SJRQ1Graphene reinforced hybrid-bioceramic coatings on porous-Ti6Al4V for biomedical applications: morphology, corrosion resistance, and cell viability
Aslan, N.; Aksakal, B.; Dikici, B.; Sinirlioglu, Z.A.
The effect of Hydroxyapatite (HA)-based coatings reinforced with reduced graphene oxide (rGO) on porous-Ti6Al4V (P-Ti6Al4V) alloys in terms of electrochemical corrosion and cell viability for potential biomedical applications was investigated in this study. The scaffold-porous surfaces of P-Ti6Al4V were coated by the biocomposite structure of HA and reduced graphene oxide (rGO) at various porosity rates (40, 50, and 60%) by using the sol–gel dip-coating method. The results of 0.5, 1.0, and 1.5 wt% rGO-HA coatings were compared to coatings that contained only HA (free-rGO). Raman spectroscopy, X-ray diffractometer, and scanning electron microscopy were used for structural and morphological characterizations. The coatings in vitro corrosion susceptibilities were tested in simulated body fluid at 37 °C. Compared to free-rGO coatings, the results showed that rGO reinforcements phases reduced the corrosion rate of the scaffolds. The corrosion rate increased as the porosity content of the scaffolds increased. In vitro cell viability tests revealed that samples of 0.5 and 1.0 wt% rGO-HA coating groups performed better than the control and 1.5 wt% rGO-HA samples. Graphical abstract: [Figure not available: see fulltext.]
AtıfScopus8WoS7OpenAlex6İncele - MakaleAçık Erişim2022Scopus SJRQ3Electrochemical Detection of Ivermectin Used for the Treatment of COVID-19 with Glutardialdehyde-Modified Glassy Carbon Electrode
Koçak, Berna; İpek, Yeliz
In this study, the surface of the glassy carbon electrode was modified with glutardialdehyde. The modified glassy carbon electrode showed electrocatalytic activity against ivermectin. The glassy carbon electrode modified with glutardialdehyde showed high sensitivity, selectivity, and stability in the determination of ivermectin. The peak current of glutardialdehyde oxidation obtained by differential pulse voltammetry decreased inversely with the ivermectin concentration. Ivermectin inhibited the oxidation reaction of glutardialdehyde and caused a decrease in current. This change made the analysis of ivermectin electrochemically possible. In order to demonstrate the applicability of the developed method in real samples, recovery studies were carried out in tap water and urine. The highest sensitivity (0.45 µA/((µmol·L−1)(cm2))) was achieved with urine sample and the lowest detection limit as 2.66 × 10−6 mol·L−1 was obtained with BRT solution sample. Graphical abstract: [Figure not available: see fulltext.]
AtıfScopus14WoS13OpenAlex13İncele - MakaleYalnız künye2022Scopus SJRQ3Continuous Flow–Assisted Polyol Synthesis of Citric Acid Functionalized Iron Oxide Nanoparticles
Akkurt, Nevzat; Altan, Cem Levent; Sarac, Mehmet Fahri
The synthesis of nanoparticles by the continuous flow process is of great interest since it allows extensive control over reaction conditions with high precision and provides enhanced production capacity with excellent heat and mass transfer rates at high pressures and temperatures. In this study, iron oxide nanoparticles were synthesized via continuous flow process in combined micro- and milli-sized reactors in the presence of citric acid at variable functional ratios from 1:1 to 1:5. The results illustrated the possibility of continuous production of superparamagnetic magnetite and/or maghemite nanoparticles at the size range of 4.3 to 4.6 nm that exhibit remarkable colloidal stability in triethylene glycol (TEG) and saturation magnetizations up to 52 emu/g. Additionally, the nucleation and growth stages of nanoparticles were found to be unaffected by the presence of citric acid (CA) while an increase in the functional ratio was shown to affect the magnetic properties due to the presence of a non-magnetic layer around the particles. Furthermore, the viability of human lung adenocarcinoma (A549) cell lines was investigated with several concentrations of magnetic nanoparticles, and the biocompatibility of nanoparticles was illustrated at certain particle loadings after 48 h expressing the potential use in biomedical applications.
AtıfScopus9WoS9OpenAlex9İncele - 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