Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(102)
- Güler, Ömer(69)
- Akkurt, Nevzat(68)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(49)
- Celik, Erkan(45)
- Zengin, Gokhan(40)
- Serdar, Osman(39)
- Kocabaş, Mehmet(37)
- Aslan, Naim(31)
- Baskonus, Haci Mehmet(31)
- Bulut, Hasan(31)
- Mete, Suleyman(31)
- Paksoy, Mehmet Yavuz(30)
- Kök, Mediha(27)
- Ince, Muharrem(26)
- Yildirim, Ozal(26)
- Özkul, İskender(26)
- Sulaiman, Tukur Abdulkadir(25)
- Topal, Murat(25)
- Guler, Omer(24)
- Serin, Faruk(23)
- Benzer, Fulya(22)
- Erten, Fusun(22)
- Alataş, Mevlüt(21)
- Güler, Seval Hale(21)
- Baykal, Duygu Sen(20)
- Taşgın, Yahya(20)
- Kutlu, Banu(19)
- Onat, Onur(19)
- Sahin, Kazim(19)
- Tanyol, Mehtap(19)
- Torğut, Gülben(19)
- Yildirim, Numan(19)
- Kahraman, Gökhan(18)
- Orhan, Cemal(18)
- Say, Yakup(18)
- Susam, Selim Orhun(18)
- Utku, Anıl(18)
Yayınlar
- MakaleYalnız künye2022Scopus SJRQ3Identification of Potential Inhibitors for Severe Acute Respiratory Syndrome-related Coronavirus 2 (SARS-CoV-2) Angiotensin-converting Enzyme 2 and the Main Protease from Anatolian Traditional Plants
Kılınç, Namık; Açar, Mikail; Tuncay, Salih; Karasakal, Ömer Faruk
Background: The 2019 novel coronavirus disease (COVID-19) has caused a global health catastrophe by affecting the human population around the globe. Unfortunately, there is no specific medi-cation or treatment currently available for COVID-19. Objective: It is extremely important to find effective drug treatment in order to put an end to this pandemic period and return to normal daily life. In this context and considering the urgency, rather than focusing on the discovery of novel compounds, it is critical to explore the effects of existing herbal agents with proven antiviral properties on the virus. Methods: Molecular docking studies were carried out employing three different methods, Glide extra precision (XP) docking, induced fit docking (IFD), and molecular mechanics/generalized born surface area (MM/GBSA), to determine the potential antiviral and antibacterial effects of 58 phytochemicals present in Rosmarinus officinalis, Thymbra spicata, Satureja thymbra, and Stachys lavandulifolia plants against the main protease (Mpro) and angiotensin-converting enzyme 2 (ACE2) enzymes. Results: 7 compounds stood out among all the molecules, showing very high binding affinities. Accord-ing to our findings, the substances chlorogenic acid, rosmarinic acid, and rosmanol exhibited extremely significant binding affinities for both Mpro and ACE2 enzymes. Furthermore, carnosic acid and alpha-cadinol showed potent anti-Mpro activity, whereas caffeic acid and carvacrol exhibited promising anti-ACE2 activity. Conclusion: Chlorogenic acid, rosmarinic acid, rosmanol, carnosic acid, alpha-cadinol, caffeic acid, and carvacrol compounds have been shown to be powerful anti-SARS-CoV-2 agents in docking simulations against Mpro and ACE2 enzymes, as well as ADME investigations.
AtıfScopus32WoS30OpenAlex31
İncele - MakaleAçık Erişim2022Scopus SJRQ3Local scour at a bridge abutment along a curved channel
Korkmaz, Meral; Emin Emiroglu, M.
Few studies have focused on abutments located on curved channels; previous studies have typically focused on straight channels. The present study experimentally examined the local scour that occurs around abutments of different lengths placed on inner and outer banks along a curved channel under clear-water scour flow conditions. The local scour around an abutment in a curved channel is a function of the upstream Froude number, flow intensity, the angle of the bend curvature and the ratios of abutment length to flow depth, abutment length to abutment width and abutment length to channel width. The maximum scour depth around the abutments placed on the outer bank was 1.45 times the scour depth on the inner bank. An empirical equation was developed containing all the dimensional parameters for equilibrium scour depth. The average percentage error of the proposed equation was 2%.
AtıfScopus3WoS3OpenAlex2İncele - MakaleAçık Erişim2022Distribution Centre Location Selection for Disaster Logistics with Integrated Goal Programming-AHP based TOPSIS Method at the City Level
Göçmen Polat, Elifcan
The importance of disaster logistics and its share in the logistics sector are increasing significantly. Most disasters are difficult to predict; therefore, a set of measures seems to be necessary to reduce the risks. Thus, disaster logistics needs to be designed with the pre-disaster and post-disaster measures. These disasters are experienced intensely in Turkey and the importance of these measures becomes more evidential. Therefore, accurate models are required to develop an effective disaster preparedness system. One of the most important decisions to increase the preparedness is to locate the centres for handling material inventory. In this context, this paper analyses the response phase designing the disaster distribution centres in Turkey at the provincial level. AHP (Analytical Hierarchy Process) based TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) method and goal programming model integration is used to decide alternative locations of distribution centres. TOPSIS method is employed for ranking the locations, which is based on hazard scores, total area, population, and distance to centre. Two conflicting objectives are first proposed in the goal programming formulation, in which maximization of the TOPSIS scores and minimization of the number of distribution centres covering all demands named set covering model are included. Although Gecimli has the highest priority with 0.8 p score in the TOPSIS ranking, Altincevre (0.77) and Buzlupınar (0.75) ensure both the TOPSIS score and coverage of the demand nodes. The results from this paper confirm that the computational results ensure disaster prevention insights especially in regions with limited data.
AtıfScopus15TR Dizin3
İncele - MakaleYalnız künye2022Scopus SJRQ2Naphthol green B Removal using a Novel Hydrogel Composite: Thermodynamics, Isotherms, Kinetics and Optimization by RSM
Pıhtılı, Güzin; Tanyol, Mehtap; Birkan, Kubra
In this study, the efficiency of the Poly(4-vinylpyridine-co-acrylamide) doped with EuCl3 {(Poly(4-VP-co-AAM)/EuCl3)} hydrogel synthesized in the laboratory by free radical in-situ polymerization method in removing naphthol green B (NGB) from wastewater was investigated. The structural properties of the adsorbent have been described by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The dependence of NGB adsorption performance on varying such as the amount of adsorbent, initial NGB concentration and contact time were investigated in a batch system. To determine the interaction effects of the selected parameters on the adsorption process and to optimize the adsorption capacity of the process, the central composite design (CCD) in the response surface methodology (RSM) was used. Optimum conditions were found to be 110 mg/L NGB concentration, 0.05 g/100 mL Poly(4-VP-co-AAM)/EuCl3/EuCl3 dosage and 165.81 min contact time. The adsorption capacity and removal efficiency under these conditions were 206.46 mg/g and 92.50 %, respectively. Experimental equilibrium data were in better agreement with the Langmuir isotherm. The kinetic results indicated that the adsorption process can be defined by pseudo-second-order kinetic with internal diffusion as one of the rate-determining steps. The adsorption process was found to be exothermic and spontaneous. Experimental results showed that dye can be successfully removed from wastewaters using Poly(4-VP-co-AAM)/EuCl3 hydrogel as adsorbent.
AtıfScopus5WoS5OpenAlex6İncele - MakaleAçık Erişim2022Evaluation of health managers’ opinions about decentralization in health services; [Sağlık Yöneticilerinin Sağlık Hizmetlerinde Desantralizasyona İlişkin Görüşlerinin Değerlendirilmesi]
Bas, Kazim; Sur, Haydar
OBJECTIVE: It was aimed to determine the opinions of health-care managers on theimplementation of decentralization in health-care services. METHODS: The research is a cross-sectional and descriptive study.Sample of the study included 261 health managers. Research data were collected from health-care managers between June 8 and July 17, 2020, using face-to-face interviews technic by a questionnaire, in an average of 20–25 minutes. The obtained data were transferred to the computer environment and analyzed with the number, percentage, and Chi-square tests. RESULTS: About 52.5% of the health managers stated that health-care services should be provided by the public, 63.2% of them stated that health-care services should be a form of empowered decentralization, 41.8% of them stated that decentralization could be successful in Turkiye, 62.6% stated that decentralization would provide flexibility in health-care management, 70.3% of them said that it could find solutions to the problems, and 73.3% of them stated that it will improve employee performance whereas 44.9% of them stated that it would negatively affect providing services in integrity, 67.2% of them stated that it would cause regional inequalities, 73.2% of them said that local factors will intervene in health-care services, and 57.9% reported that it would weaken the central power. CONCLUSION: The majority of health-care managers prefer that health-care services are provided by the public health-care service and prefer the empowered decentralization of health-care services. More than half of the health-care managers expressed their positive views such as the fact that decentralization provides flexibility in health-care services, improve the performance, and participation in service along with the negative views such as the fact that decentralization negatively affects the service delivery, causes regional inequalities and intervention of local factors, and weakens the central power.
AtıfScopus1WoS1OpenAlex2
İncele - MakaleYalnız künye2022Scopus SJRQ3Plug-in Estimation of Dependence Characteristics of Archimedean Copula via Bézier Curve
Susam, Selim Orhun; Erdoğan, Mahmut Sami
• This article introduces measurement of the dependence between variables with a dependence structure defined by Archimedean copulas. The estimation of the dependence measure, such as Kendall’s tau as well as the lower and upper tail dependence, is investigated by using estimation of the Kendall distribution function based on the Bézier curve. A Monte Carlo study is performed to measure the performance of the new estimation method. The simulation results showed that the proposed methods has good results in terms of estimation performance. The new estimators are also used to estimate the dependence coefficients for three sets of real data.
AtıfScopus1WoS1İncele - MakaleAçık Erişim2022Scopus SJRQ1A new mobile convolutional neural network-based approach for pixel-wise road surface crack detection
Doğan, Gürkan; Ergen, Burhan
In recent years, the worldwide road network has grown rapidly and reached an enormous size. Parallel to this size of the road network, the imperfections on the road surfaces are just as large. This has led to a significant increase in road maintenance costs for traffic management departments. Researchers have proposed methods for automatic flaw detection using deep neural networks to reduce road maintenance costs. However, these methods are insufficient in terms of performance and lightness. In this study, a convolutional neural network-based approach is proposed, which provides more successful road surface crack detection and requires less lightweight compared to other studies. Since the performance of the proposed approach is higher and more lightweight, it can be used more effectively and efficiently in mobile systems.
AtıfScopus60WoS55OpenAlex63İncele - MakaleYalnız künye2022Scopus SJRQ2Investigation of electrical conductivity and bioactive quality during ohmic evaporation process of Apple juice
Karakavuk, Emrah; Goksu, Ali; Sabanci, Serdal
In this study, the evaporation of apple juice was completed with ohmic heating to eliminate some problems with conventional evaporation methods. Ohmic evaporation (OE) was performed at different voltage gradients (13–17 V/cm) for determining electrical conductivity (EC), Hydroxymethylfurfural (HMF), and the total phenolic content (TPC) changes. The voltage gradient affected the total consumed energy, average power, and specific water removal ratio (SWRR) values (p <.05). The shortest time was obtained at 17 V/cm, while the longest time was 13 V/cm during the OE process. The EC value varies between 0.19–0.85 S/m for the voltage gradients. EC and current values increase with temperature until boiling starts, then decrease, and the EC value tends to increase slightly. The TPC value ranged between 587.4–716,4 mg GAE/100 g and was higher at OE than in the conventional process. As a result, the OE process preserves the TPC value of apple juice better while shortening the processing time. Novelty impact statement: The ohmic evaporation process is an alternative method that can be preferred in concentrating fruit juices with consuming less energy and obtaining higher quality products. In addition, considering the phenolic distribution, it was determined in this study that the products were better preserved in the ohmic evaporation process. It is predicted that it will provide important data for both pilot and industrial designs for the establishment of any ohmic evaporation systems.
AtıfScopus6WoS5OpenAlex9İncele - Derleme MakaleAçık Erişim2022Scopus SJRQ1Inverted Solar Stills: A Comprehensive Review of Designs, Mathematical Models, Performance, and Modern Combinations
Hussein, Ahmed Kadhim; Rashid, Farhan Lafta; Abed, Azher M.; Al-Khaleel, Mohammad; Togun, Hussein; Ali, Bagh; Akkurt, Nevzat; Malekshah, Emad Hasani; Biswal, Uddhaba; Al-Obaidi, Mudhar A.
Fresh water is scarce, making it a worldwide issue. In order to address global freshwater demand, a filtration technique is needed. Solar distillation (SD) that purifies brackish and sub-terranean water has been proven to be a promising green technology. It produces distilled water which can be used as potable water for drinking and other purposes. The designs, operations, and configurations of several inverted solar stills are thoroughly examined in this article. All techniques for solar water distillation to separate saltwater from freshwater have the same fundamental idea. It has been demonstrated that for a specified mass of water in the top basin, the daily output of an inverted absorber double-basin solar still (IASS) grows with increasing water depth in the bottom basin. Nevertheless, as the water depth in the bottom basin rises from 1 cm to 5 cm, the output of an inverted absorber double-basin solar system falls by about 27%. At water depths of 4, 6, and 8 cm, the daily yields from inverted absorber solar stills paired with a refrigeration cycle (RIASS) were 6.4, 10.08, and 9.5 L/day, respectively. The results also showed a substantial rise in water temperature in the inverted absorber solar still as a result of lower bottom heat loss and larger absorptivity. In this study, the emphasis on energy, efficiency, and environmental concerns remains with the modified multi-wick basin-type inverted absorber solar panel. The performance of the inverted trickling solar still was assessed with a 60 ppm average salinity under various sun radiation, feed water flow rate, and existence conditions for natural convection. It was found that the still could produce 2.55 L/day m2 of fresh water, a 15% increase. Brackish water with a salinity of 6000 ppm was used to test the still in November at tilt angles of 47◦ and 32◦ . Condensate production at the specified angles was 2.8 and 2 L/d, respectively. A total output of 6.907, 5.681, and 4.650 kg/m2 /day was also generated using the modified multi-wick basin-type inverted absorber solar still (MMWBIASS) at water depths of 1, 2, and 3 cm, respectively. With black cotton wicks, the MMWBIASS had a total thermal efficiency of 34.04%, 28.17%, and 23.61%.
AtıfScopus43OpenAlex47İncele - MakaleYalnız künye2022Scopus SJRQ1Occupational health, safety and environmental risk assessment in textile production industry through a Bayesian BWM-VIKOR approach
Ak, M. Fatih; Yucesan, Melih; Gul, Muhammet
Occupational risk assessment (ORA) is a process that consists of evaluating, ranking, and classifying the hazards and associated risks arising in any workplace from the viewpoint of occupational health and safety. Many ORA methods have been proposed in the literature, from a single independent expert to participatory methodologies made by group decision and simple to complex ones. In this paper, a holistic ORA is presented, which uses two important multi-attribute decision methods named Bayesian Best-Worst Method (Bayesian BWM) and VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR). Bayesian BWM is used to determine the importance weights of six different assessment criteria, which are the probability of hazardous event (P), frequency (F), severity (S), detectability (D), cost (C) and sensitivity not to use personal protective equipment (SNP). Since the classical BWM finds solution to the weights of a number of criteria from only one expert's judgment, Bayesian BWM is preferred in this paper (1) to enable participation of a group of experts, (2) to aggregate the preferences of these multiple experts into consensus without loss of information and (3) to follow a probabilistic way for solving the ORA problem. The hazards are then ranked by VIKOR. The approach is implemented in the ORA process of a textile production plant. Results of risk analysis showed that electricity hazard and associated risks constitute the highest risk ratings. These hazards arise from the product, process, human and working environment. The associated risks are evaluated, prioritized, and detailed control measures are proposed. This study made comparisons with the classical BWM-VIKOR approach to demonstrate the proposed approach's difference and practicality. Results can also help practitioners and risk analysts in formulating the improvement measures to increase the overall safety of the working environment further.
AtıfScopus87WoS78OpenAlex87İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ2Dental Material Detection based on Faster Regional Convolutional Neural Networks and Shape Features
Imak, Andaç; Çelebi, Adalet; Türkoğlu, Muammer; Şengür, Abdulkadir
In this paper, a novel approach is proposed to detect the dental materials in dental Panoramic images. In general, dental Panoramic images are examined by the dentists to detect the dental materials of the patients. Examining the dental Panoramic images is a time-consuming procedure and necessitates highly skilled dentists. Thus, computer imaging and decision support systems based on machine learning are in demand for dental applications. In this study, a semi-automatic, image processing and machine learning based approach is proposed for detection of dental materials in dental Panoramic images. More specifically, the dental materials namely dental filling, dental bridge and tooth crown are targeted by the proposed approach. Within the approach developed, the dental Panoramic images used as input are initially pre-processed for noise removal and tooth region is determined using a deep learning approach. To this end, a faster Regional Convolutional Neural Networks (RCNN) method is employed. A tooth region correction procedure is applied after application of faster RCNN to determine the exact location of the tooth region as faster RCNN may produce more tooth regions than one correct tooth region. Graph cut (GC) based image segmentation is applied to segment the tooth region into foreground and background regions. Shape based feature extraction and classification are applied to determine the tooth problem. A dataset has been established in dental faculty hospital of private dental clinics. The proposed approach is simple yet quite effective. In all classification methods, the average accuracy scores were around 90%.
AtıfScopus9WoS7OpenAlex10İncele - MakaleAçık Erişim2022Calculation of Dynamic Properties of Drug-Added Aqueous Solutions with T1 and T2 Relaxation Times; [İlaç Katkılı Sulu Çözeltilerin Dinamik Özelliklerinin T1 ve T2 Rölaksasyon Zamanları ile Hesaplanması]
Korunur, Sibel
The development of modern spectroscopic methods has facilitated and accelerated structure analysis. The NMR method is the most popular way to perform structural analysis of compounds with very complex structures. D2O is a solvent that is frequently used in NMR analysis of both chemical molecules and many biological molecules such as drugs, proteins, and enzymes. In this paper, the study of residual water in proton drug-added protein solutions was carried out via NMR relaxation. The spin-lattice (T1) and the spin-spin relaxation (T2) times of residual water in drug-added protein solutions were studied depending on temperature by Avance Bruker 400 MHz1H-NMR Spectrometer, and activation energies (E! ) and rotational correlation times (τ" and τ# ) have been determined for T1 and T2 relaxation times.
- MakaleAçık Erişim2022Scopus SJRQ2Investigation of the effect of the life satisfaction and psychological well-being of nursing students on their happiness levels
Yeşi̇ltepe, Akgün; Sayar, Serap; Çal, Ayşe
Purpose: This study aims to examine the effect of nursing students' life satisfaction and psychological well-being on their perceived happiness levels. Method: The study, which was designed as a descriptive and cross-sectional study was carried out in Turkey with 264 students of nursing. Findings: Students' life satisfaction and happiness (r = 0.722), psychological well-being and happiness (r = 0.743), and psychological well-being and life satisfaction (r = 0.689) were found to be positively and highly correlated. Students' gender and perception of income status and general health status affected their happiness levels. It was revealed that life satisfaction and psychological well-being predict happiness (63.6%). Practice implications: The factors of life satisfaction and psychological well-being play a decisive role in the happiness of nursing students.
AtıfScopus19WoS18OpenAlex20İncele - MakaleAçık Erişim2022Scopus SJRQ2Synthesis and characterization of N-(2-acetyl benzofuran-3-yl) methacryl amide and ethyl methacrylate copolymer/graphite oxide composites and study of their kinetic and electrical properties
Demirelli, Kadir; Barım, Esra; Tuncer, Hülya; Barım, Gamze; Abubakar, Abdullahi Musa
Copolymers of N-(2-acetylbenzofuran-3-yl) methacrylamide (BFMAA) and ethyl methacrylate (EMA) were prepared by radical copolymerization. The composition of copolymers was estimated by 1H-NMR spectroscopy. The composites of P(BFMAA39-co-EMA) [COP1] and P(BFMAA15-co-EMA) [COP2] loaded 18 wt% graphite oxide (GO) were prepared utilizing Ultrasonic Homogenizer Sonicator Processor. The FT-IR, DSC, TGA and SEM techniques were used in the characterization of the copolymers and composites. The thermal degradation behavior of COP1 was investigated by FT-IR studies of the partially degraded copolymer. And, this copolymer was able to form a four-member amide ring and imidization via intramolecular while being heated above 340 °C. Dynamic TG analysis under argon gas was used to investigate the thermal decomposition processes of pure COP1 and COP1/GO. Two degradation models including the Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose methods were used to determine the apparent activation energy of the copolymer and its composite for approximately 65% of thermal decomposition occurred between 200 and 400 °C. The results also showed that average activation energy between 111.69 and 134.25 kJ/mol was obtained. The estimated activation energy values make it possible to build a simpler approach to expose the thermal decomposition behavior of copolymer and its composite. Dielectric and electrical behaviors of the copolymer composites having a semiconductor behavior filled with graphite oxide (GO) were investigated. The activation energy values of P(BFMAA15%-co-EMA)[COP2]/GO 18 wt% and COP1/GO 18wt% from dc conductivities were 0.182 eV and 0.245 eV, respectively.
AtıfScopus6OpenAlex8İncele - MakaleYalnız künye2022Scopus SJRQ2Performance evaluation of pectin extraction from grapefruit peel powder by ohmic heating
Goksu, Ali; Duran, Gülseven; Çilingir, Seda; Çevik, Mutlu; Sabanci, Serdal
This study is to investigate the performance properties during the extraction of pectin from grapefruit peel powder using ohmic heating. Pectin extraction was carried out under different voltage gradients (7–11 V/cm), different solid: liquid ratios (1:20–1:60), and different holding times (0–180 min) at constant pH and temperature (80°C). The voltage gradient and solid: liquid ratio affected the time to reach the target temperature. The highest energy efficiency value for all voltage gradients and solid: liquid ratios were obtained in the 0 min holding time, and the efficiency value, which changed between 89.47% and 56.02%, was negatively affected by the increase in the holding time. The exergy efficiency was lower than the energy efficiency and decreased due to the increasing holding time and decreasing voltage gradient. Also, the exergy efficiency was found to be between 73.69% and 18.09%. Determining the performance characteristics of the system will make a significant contribution to pilot and industrial-scale system/process applications for the future. Practical application: In this study, pectin was successfully obtained from grapefruit powder using an ohmic heating system. The operating conditions for the obtained pectin include constant pH (pH:1) and temperature (80°C) but various voltage gradients, solid: liquid ratios, and extraction times. It has been observed that voltage gradient and extraction time were effective on energy efficiency. When looking at exergy efficiency, voltage gradient, solid: liquid ratio, and extraction time were effective. It has been observed that the improvement potential (IP) value calculated for the system decreases depending on the increasing voltage gradient. The results obtained in this study are thought to be an important data source for literature, pilot, and industrial-scale production systems. It has been realized that ohmic heating, which is increasingly used, is an alternative technique for pectin production.
AtıfScopus13WoS12OpenAlex16İncele - MakaleAçık Erişim2022Scopus SJRQ2Investigation of the Effects of Deformation Aging Applied to AA 7075 Aluminum Alloy on Mechanical and Metallographic Properties
Taşgın, Yahya; Ergin, Ramazan
Aging is quite important in improving the mechanical properties of aluminum alloys. One of the most widely used Al alloys is AA7075 aluminum alloy. Since AA7075 aluminum alloys contain aluminum-zinc-magnesium-copper, various aging processes have been applied to improve their mechanical qualities, and as a result, they have become commercially available. When this aluminum alloy series with increased strength is subjected to any thermal effect in industrial use, the loss of mechanical properties can be reduced by applying deformation aging. In this study, the effect of deformation aging on the mechanical properties of commercially available aluminum alloy has been determined and the relationship between mechanical properties and microstructure examined. Deformation aging was applied to 7075 Al alloy in our study by cooling in air, water and oil at temperatures of 120–180 °C for 2–24 hours. Structural differences were revealed by examining the effects of heat treatment on the mechanical properties and machinability properties of the alloy. As a result of the study, it was observed that metallographic precipitation occurred in the AA7075 Al alloy, and accordingly, intermetallic phases were formed. It is thought that various nanoscale fine precipitates occurring in the matrix of this alloy can also prevent dislocation movements. The study has positive effects on the mechanical properties of the material.
AtıfScopus9WoS6OpenAlex8İncele - MakaleAçık Erişim2022Scopus SJRQ3SOME PHYTOCHEMICAL CONTENTS AND ANTIOXIDANT ACTIVITIES OF TWO PRANGOS LINDL. (UMBELLIFERA) SPECIES GROWN IN TURKEY
Hayta, Şükrü; Aydin, Sevinç; Topdemir, Aykut
The genus Prangos is a member of the Apiaceae family, and it has been a focus of the attention of researchers due to its high nutritional value and some special medical properties. In this study, the total phenolic and flavonoid contents and antioxidant activities of the leaf and fruit extracts of the Prangos ferulacea and Prangos uloptera species belonging to this genus were studied, and the properties of these two species were compared to each other. In the study, the Folin-Ciocalteu method was used for the analysis of the total phenolic content, methanolic formaldehyde was used for the total flavonoid content, and both analyses were carried out with a UV-VIS spectrophotometer device. The antioxidant activity of the specimens was measured based on the Trolox equivalent antioxidant capacity (TEAC) method. It was found that the P. ferulacea species had higher total phenolic and flavonoid content values than the P. uloptera species. The P. ferulacea species was also more effective in terms of antioxidant activity, which is known to be associated with these properties. When the fruit and leaf extracts of each species were compared, it was found that the total phenolic and flavonoid content of the fruit extract of the P. uloptera species was higher than that of its leaf extract, and the antioxidant activity of the fruit extract was also higher in proportion to these values. In the P. ferulacea species, as opposed to the case of P. uloptera, all values except for the total flavonoid values were higher in the leaf extract than the fruit extract.
- MakaleYalnız künye2022Scopus SJRQ1Cooling of non-sloped, positively sloped, and negatively sloped arrangements of Li-ion batteries with a phase change material connected to a solar system
Akkurt, Nevzat; Aghakhani, S.; Mahmoud, Mustafa Z.; Abdelrahman, Anas
Three cylindrical Li-ion batteries are simulated using COMSOL Multiphysics in this study. A circular PCM layer is used to cover the batteries. A battery pack connected to a solar system is tested to store energy in a residential building. The PCM is 100% melted at the beginning, and the frozen PCM volume fraction (PVOF) is studied over time. In addition, the temperatures of individual batteries in three different configurations are analyzed at air velocities 1 and 3 mm/s. The three battery configurations included a positive slope, a negative slope, and no slope. The finite element method (FEM) is utilized to derive algebraic equations. The test results are given to the network as training data, and different neural network architectures are tested in terms of the number of layers and the number of neurons in each layer, and finally a structure that has a minimum mean squared error as a network. Battery behavior predictor is selected. Finally, this model is given to the optimization algorithm as an optimization function to investigate the point at which the maximum voltage is obtained. The results showed that the positively sloped battery configuration decreased the temperatures of the batteries, while the non-sloped configuration increased the temperatures. In addition, the positively sloped configuration resulted in more frozen PCM than non-sloped and negatively sloped configurations at a given time. The minimum frozen PCM was observed in the non-sloped configuration. A change in the air velocity from 1 to 3 mm/s increased the frozen PCM and improved the cooling of the batteries.
AtıfScopus15OpenAlex13İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ1Self healing of alkali active mortars with expanded perlite aggregate
Yılmazer Polat, Berivan
The use of alkali-activated mortars instead of cemented mortars provides an advantage in terms of various properties such as high strength, fast curing, and high durability by terminating cement production. However, concrete cracks reduce durability and strength, thus, it is crucial that they be healed. This study aimed to investigate the healing of early microcracks in geopolymer mortars by using Sporasarcina pasteurii, which makes carbonate precipitation, and expanded perlite aggregate as the bacteria carrier. This is the first study to investigate the bacterial healing of an alkali-activated geopolymer mortar using expanded perlite aggregate without applying a complex encapsulation process to the bacterial agents. For this purpose, optical, physical, and mechanical changes caused by self-healing were observed ahead of and after the cure period with tests like water absorption, compressive strength, UPV, SEM, FTIR, and optical microscope images. The results showed that bacterial cells could sporulate directly on the expanded perlite aggregate, visually improving the crack closure rate of the samples by a majority to 100 %, and the unit weights of all samples healed in DM and containing bacteria increased by up to 5 %.
AtıfScopus33WoS31OpenAlex28İncele - MakaleAçık Erişim2022The impact of reflective practices on pre-service science teachers’ classroom teaching practices
Kılıç, Aygün
This case study attempts to explore the impact of the reflective practices (reflection in, on, and for action) on pre-service science teachers’ (PSTs’) classroom teaching practices. To this end, ten PSTs majoring in Science Teacher Education Program participated in this study. In the study, the author designed a classroom teaching practice process based on reflective practices. This process was carried out during the teaching practicum course with the pre-service teachers participating in the research. At the beginning and end of the study, classroom observations, field notes, classroom observation instruments, teaching video records, and lesson plans were used as data collection tools in determining PSTs' classroom teaching practices. The qualitative and quantitative results of this study indicated that there was a significant change in favor of post-classroom practice results between PSTs' pre-and post-classroom teaching practices. Given these results, the classroom practice process based on the reflective practices carried out in the research plays an important role in the development of PSTs' classroom teaching practices.
AtıfScopus20OpenAlex24İncele