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Koleksiyondaki öğeler
- MakaleAçık Erişim2023Scopus SJRQ1An extensive survey on radiation protection features of novel hafnium iron-borophosphate glasses: Experimental and theoretical study
Şakar, Erdem; Alım, Bünyamin; Ertap, Hüseyin; Karabulut, Mevlut
This study aimed to determine the radiation (photon and particle) attenuation abilities of Hf added iron-borophosphate glasses considered as a candidate host matrix for Pu containing nuclear waste. Experimental absorption parameters were measured using 133Ba radionuclide for photon radiation, and the same parameters were theoretically calculated using Phy-X/PSD. The obtained data were evaluated comparatively for all glasses depending on the Hf and B contents. It has been determined that all of the glasses examined have photon absorption ability at a level that can be a shielding material for nuclear applications. In addition, the interaction cross-sections with particle radiations were computed using SRIM and ESTAR software. When the data obtained are evaluated thoroughly, it can be said that investigated glasses can be used as shielding in areas that require protection from both photon and particle radiation, in addition to being a candidate material for the vitrification of nuclear wastes containing Pu.
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İncele - Derleme MakaleAçık Erişim2023Scopus SJRQ2A Meta-Analytic Review of the Effect of Socioeconomic Status on Academic Performance
Selvitopu, Abdullah; Kaya, Metin
The two main purposes of the current meta-analysis were (a) to determine the relation between socioeconomic status (SES) of students and academic performance (AP) (b) and evaluate the effect of several potential moderating factors in this relation. Data covered the publications between 2010 and 2019, and the dataset consisted of 48 independent studies that included 62 different samples, and the total sample was 386.601. Findings revealed that the relation between SES and academic performance represented a moderate positive correlation. All moderators, type of SES measure, academic performance scale, location, grade level, subjects of academic performance, and year, produced significant effects, respectively. These findings were discussed for every category of moderators with the related literature.
AtıfScopus65WoS54OpenAlex81İncele - MakaleAçık Erişim2023Scopus SJRQ1Optimizing the seismic resilience performance of steel truss bridges by maximum energy dissipation via friction dampers
Artar, Musa; Carbas, Serdar
The primary aim of this study is to propose an innovative design methodology for optimizing the seismic resilience performance of steel truss bridges by dissipating the maximum input seismic energy. Maximum seismic energy dissipation is carried out by means of Pall friction dampers (PFDs), popularly categorized among passive energy-damping devices. PFDs distribute input seismic energy with a slip motion along with friction during an earthquake. For that, it is important to determine the optimal slip load value for the PFDs to start working before the structural elements reach the yield point. To determine the optimal slip load values of the PFDs under earthquake effects, the maximum seismic energy distribution is assured by nature-inspired Squirrel Search (SS) and Water Strider (WS) metaheuristic algorithms for steel truss bridges equipped with PFDs. Finally, steel truss bridges on which PFDs with optimal slip load values have been implemented are optimally designed to achieve the minimal structural weight while satisfying ASD-AISC Code of Practice requirements. In order to demonstrate the validity of the proposed design methodology, two design examples of 113-member and 465-member steel truss bridges steel are presented. The optimal slip loads attained with the SS and WS algorithms by conducting the proposed design methodology are 2.45% and 3.75% of the structural weight for the first design example and 2.64% and 2.63% of the structural weight for the second design example, respectively, which are much lower than those considered in practical applications. Moreover, the numerical results show that by 93.5% and 99.48% maximum distribution rates of input seismic energy are accomplished in the bridges. The results indicate that the proposed design methodology exhibit superior performance in optimizing the seismic resilience performance of steel truss bridges by maximum energy dissipation via friction dampers.
AtıfScopus8WoS4OpenAlex5İncele - MakaleAçık Erişim2024Scopus SJRQ3Nonlinear optical response of LinClK (n = 1–6) superalkali clusters
Şentürk, Şükrü; Ekincioğlu, Yavuz; Doğan, Ümit
The geometrical structures, stabilities, electronic properties and nonlinear optical response of the halogen doped bimetallic LinClK (n = 1–6) clusters were studied within the density functional theory. Based on the dissociation energy, second order energy difference and GH-L (HOMO-LUMO gap), the LinClK (n = 2, 4, 6) clusters are more stable. According to their ionization energies, the clusters can be classified as a superalkali. From the NBO analysis, the clusters are excess electron systems. The obtained first static hyperpolarizability (o) values are in the range of 1.56 × 104 − 4.33 × 104 au while the second static hyperpolarizability vary within 2.47 × 106 au to 13.9 × 106 au for the LinClK (n = 1–6) superalkalis that are slightly higher than the nonlinear optical response of halogen doped monometallic clusters. More importantly, the Li5ClK is transparent in the deep UV region ( < 300 nm) among the superalkalis indicating that the Li5ClK superalkali can be a candidate structure as new member of NLO materials.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2024Scopus SJRQ3Artificial Neural Network and Multiple RegresAnalysis Applied to 2D-QSAR Studies: the Caof Imidazolidine-2,4-dione as PTP1B Inhibito
Aggoun, Siham; Belaidi, Salah; Ghamri, Meriam; Kerassa, Aicha; Cinar, Mehmet; Yamari, Imane; Abchir, Oussama; Chtita, Samir
In this investigation, we undertook a comprehensive quantitative structure-activity relationship (QSAR) analysis using both modern artificial neural network (ANN) methods and classical multiple linear regression methods (MLR). Our primary focus was on revealing the intricate connection between antidiabetic activity and the molecular structure of thirty-nine imidazolidine-2,4-dione derivatives. The B3LYP hybrid functional and 6-31G (d) basis set computed electronic properties at the quantum level. Rigorous benchmarking against experimental data validated the reliability of our quantum theory approach. Our statistical model effectively predicted activities closely aligned with experimental antidiabetic activities, quantified by the IC50 values. They also revealed a significant superiority of the ANN architecture (6-4-1) over the MLR method. This study stands as a meaningful contribution to the field, providing valuable insights for designing new antidiabetic drugs, particularly as potential inhibitors of tyrosine phosphate 1B (PTP1B). The explicit articulation of our primary aim and emphasis on the study’s significance underscore its potential impact on advancing drug development within the realm of antidiabetic therapeutics.
AtıfScopus2İncele - Derleme MakaleAçık Erişim2024Scopus SJRQ1Oxidative stability, quality, and bioactive compounds of oils obtained by ultrasound and microwave-assisted oil extraction
Walayat, Noman; Yurdunuseven-Yıldız, Aysun; Kumar, Manoj; Goksen, Gulden; Öztekin, Sebahat; Lorenzo, José Manuel
Vegetable oils are extracted from oilseeds, fruits and other parts of plants. The method used in oil extraction is of great importance, as it affects both the quality of the final product and the environment. It is desirable that the extraction method be minimally costly, fast, environmentally friendly, and produce oil of high quality and quantity. Common oil extraction methods are mechanical pressing and solvent extraction, and these methods have advantages and disadvantages over each other. Mechanical extraction and solvent extraction are controversial due to poor product quality and high environmental impacts. This review presents applications where conventional oil extraction processes are assisted by microwave or ultrasound. It is necessary to evaluate the impact of ultrasound and microwave-assisted extraction on the quality of the extracted oil and also to compare the results with those of conventional extraction methods. For this purpose, this review discusses the effects of microwave and ultrasound-assisted extraction on the physicochemical, oxidation indices, bioactive compounds, and antioxidant properties of oil extracted from oil seeds and fruits. Furthermore, this review provides readers with in-depth information on the mechanisms involved, their use, and the impact of operating conditions. The yield and quality of the oil obtained by these processes can vary depending on parameters such as microwave power, ultrasound power, processing time, and temperature. Finally, the review also discusses the challenges and advantages of the industrial application of these technologies.
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İncele - MakaleAçık Erişim2024Scopus SJRQ3The relationship between parental awareness of sexual abuse and children's skills to say «no»; [Relación entre la conciencia de madres y padres sobre el abuso sexual y las habilidades de los niños para decir «no»]
Kirbaş, Zila Özlem; Şahin, Emel
Introduction: Child sexual abuse is a global and multidimensional social problem and causes devastating and permanent psychological, emotional, cognitive, behavioural, physical, sexual and interpersonal sequelae. This study examines the relationship between the ability to say «no» and parental awareness of sexual abuse in 4th grade primary school students. Methods: The study was conducted between April 2022 and June 2022 in primary schools in the central district of a province in north-eastern Turkey. The sample consisted of 310 students enrolled in 4th grade and their parents. We collected the data through a personal information form, the ability to say «no» scale for children and the sexual abuse awareness scale for parents. Results: There was a weak positive correlation between the mean maternal scores of sexual abuse awareness and the mean scores of refusal and resistance in children (P ˂ .05), as well as a weak positive correlation between the mean paternal scores of sexual abuse awareness and the mean scores of refusal and resistance in children (P ˂ .05). Conclusion: As mothers’ and fathers’ awareness of sexual abuse myths and of teachings and actions to combat sexual abuse increased, the refusal of children also increased. Also, as fathers’ awareness of the signs of sexual abuse increased, children's refusal increased.
AtıfScopus3WoS2OpenAlex3İncele - MakaleAçık Erişim2023Scopus SJRQ1Prevalence and predictors of psychological assistance services for older individuals in Turkish society
Coşkun, Hüseyin; Yildiz, Ibrahim; Alkan, Ömer
Background/aim: Due to the high contribution of psychological problems to the decline in the comfortable lifestyle of the older individuals, determining the factors that affect individuals' receiving psychological services and searching for solutions based on these factors is one of the primary concerns of national and international decision-makers. This study aimed to identify the factors that affect older individuals' access to psychological assistance services in Turkey. Methods: In this study, the Turkish Health Research micro dataset, which was conducted by the Turkish Statistical Institute (TURKSTAT) in 2016 and 2019, was employed. In this dataset, the data of 7,252 older individuals were analyzed. Using binary logistic analysis, the factors that are effective for obtaining psychological assistance for the older individuals were identified. Results: According to the results of the analysis, factors such as gender, education, general health status, disease status, payment of health expenditures, and body mass index affected older individuals who received psychological assistance. Conclusion: In recent years, there has been a rise in the availability of psychological assistance services for the older individuals. By identifying factors that increase the likelihood of receiving psychological assistance services, this study is expected to contribute to the creation and regulation of psychological assistance services to prevent possible psychological problems that may occur in old age, minimize the problems experienced by individuals, and promote a more comfortable lifestyle.
AtıfScopus23WoS23OpenAlex24İncele - MakaleYalnız künye2023Scopus SJRQ2The effect of guided imagery applied on geriatric orthopaedic patients on preoperative anxiety and comfort
Gunes, Huseyin; Saritas, Serdar; Ozdemir, Ahmet; Bulbul, Ali Savas
Background: This study was designed to examine the effect of guided imagery applied to geriatric orthopaedic patients on preoperative anxiety and comfort. Methods: This study was conducted as a randomized controlled trial. The population of the study consisted of geriatric patients treated in the orthopaedics and traumatology clinic of a university hospital. The sample consisted of 80 patients, including the experimental group (n = 40) and the control group (n = 40). Personal Descriptive Form, The State–Trait Anxiety Inventory (STAI) and General Comfort Scale were used as data collection tools. Results: After the guided imagery application, it was determined that the anxiety of the experimental group decreased statistically significantly, and their comfort improved (P < 0.05). Conclusion: After the imagery, it was determined that the patients in the experimental group had a decrease in their anxiety level and an improvement in their comfort. Since it is a low-cost and easily accessible method, applying imagery in the preoperative period is recommended.
AtıfScopus5WoS5OpenAlex5İncele - MakaleAçık Erişim2025Scopus SJRQ3Online software for a new risk assessment method in occupational health and safety: RSCAL
Ateş, Fatih Mehmet; Doğan, Ömer
Risk assessment is necessary for the safety of employees in the workplace. Risk assessment methods contain some deficiencies arising from the persons performing the analysis. In order to partially overcome this situation, a risk assessment method has been developed by the authors by utilizing the data on occupational accidents in Turkey. In the method, Occupational Health and Safety Professionals who will perform the risk assessment can calculate the risk score without giving a numerical value for any hazard and corresponding risk that they identify in the workplace. In the study, a user-friendly online software called RSCAL by the authors, with a web address of https://rscal.com.tr/, which can meet all the above-mentioned requirements and calculate risk scores for workplaces serving in all types of sectors, has been developed. Through this online application, the identified hazard, risk and exposures of the business to be analyzed can be selected; the necessary corrective and preventive actions can be written by the user and then the risk score can be calculated. After that, all hazards specific to the enterprise can be meticulously identified and the risk assessment of the enterprise can be made by calculating the risk scores. This risk assessment can also be printed out in excel file format. In the future, parameters such as the deadline for each hazard, the legal requirement or standard from which the corrective preventive action to be taken arises can be added to the RSCAL calculation tool.
AtıfScopus1İncele - Derleme MakaleAçık Erişim2024Scopus SJRQ1Quality and stability of frying oils and fried foods in ultrasound and microwave–assisted frying processes and hybrid technologies
Yildiz, Aysun Yurdunuseven; Echegaray, Noemí; Öztekin, Sebahat; Lorenzo, José Manuel
Frying is a popular cooking method that produces delicious and crispy foods but can also lead to oil degradation and the formation of health-detrimental compounds in the dishes. Chemical reactions such as oxidation, hydrolysis, and polymerization contribute to these changes. In this context, emerging technologies like ultrasound-assisted frying (USF) and microwave (MW)-assisted frying show promise in enhancing the quality and stability of frying oils and fried foods. This review examines the impact of these innovative technologies, delving into the principles of these processes, their influence on the chemical composition of oils, and their implications for the overall quality of fried food products with a focus on reducing oil degradation and enhancing the nutritional and sensory properties of the fried food. Additionally, the article initially addresses the various reactions occurring in oils during the frying process and their influencing factors. The advantages and challenges of USF and MW-assisted frying are also highlighted in comparison to traditional frying methods, demonstrating how these innovative techniques have the potential to improve the quality and stability of oils and fried foods.
AtıfScopus35WoS33OpenAlex39İncele - MakaleAçık Erişim2022Scopus SJRQ1Identification of Lactic Acid Bacteria (LAB) from pre-fermented liquids of selected cereals and legumes and characterization of their exopolysaccharides (EPS)
Yalmanci, Dilara; İspirli, Hümeyra; Dertli, Enes
Recently, isolation of Lactic Acid Bacteria (LAB) strains with important technological functions from plant-based products has gained special interests related with the increment of consumer preferences to the plant-based fermented products. In this context, various cereals and legumes that were underwent to germination or not were selected for the isolation of exopolysaccharide (EPS) producer LAB strains in this study. Following genotypic discrimination, 17 distinct strains belonging to Weissella confusa, Weissella cibaria, Lactococcus lactis subsp. hordniae, Leuconostoc lactis, Lactiplantibacillus plantarum and Leuconostoc mesenteroides were identified from pre-ferment liquids. Two strains Weissella confusa W-16 and Leuconostoc lactis GW-6 were the highest EPS producers, and their EPSs were further characterized. The 1H and 13C NMR results revealed that both strains were dextran producers containing (1 → 3)-linked α-D-glucose units as branches with 9.2% and 6.9% levels for Weissella confusa W-16 and Leuconostoc lactis GW-6, respectively. FTIR analysis also supported the dextran structure and demonstrated the functional groups within the dextrans. A high level of thermal stability was observed in both dextrans detected by TGA and DSC analysis. Both dextrans were in amorphous characteristics determined by XRD analysis. These findings demonstrate that pre-fermented liquids of different cereals and legumes can be source of technologically important LAB strains with EPS production characteristics.
AtıfScopus41WoS41OpenAlex42İncele - MakaleAçık Erişim2023Scopus SJRQ2Efficient bio-catalytic production of enentiopure (S)-(4-chlorophenyl)(phenyl)methanol as a drug precursor by using a novel rotatable composite design-based optimization strategy
Tozlu, Nesrullah; Bülbül, Ali Savaş; Özdemir, Akın; Şahin, Engin
Asymmetric bioreductions catalyzed by biocatalysts have demonstrated great promise in manufacturing chiral alcohols. On the other hand, the synthesis of (S)-(4-chlorophenyl)(phenyl)methanol ((S)-2), precursors of L-cloprastine and carbinoxamine, still presents considerable challenges due to the inadequate substrate quantity and production process. In this work, a novel rotatable composite design-based optimization technique was used with the Lactobacillus paracasei BD101 biocatalyst for the asymmetric reduction of (4-chlorophenyl)(phenyl)methanone (1). Optimization conditions of the reaction were determined by the proposed optimization strategy as: pH=5.85, temperature=37 °C, incubation time=71 h, and agitation speed=120 rpm. The reaction conversion and the product of enantiomeric excess (ee) were also predicted to be 97% and 99%, respectively. In the experimental study performed under the determined optimized conditions, (S)-2 was obtained with >99% ee, >99% conversion, and 97% yield. In addition, 1 with the amount of 15.166 g was completely converted to (S)-2 (14.85 g, 97% isolated yield) on a high-gram scale. Notice that the manufacture of (S)-2 on a gram scale utilizing a biocatalyst and an optimization technique is demonstrated in this work for the first time. Finally, an economical, effective, and environmentally friendly biocatalytic process for the biocatalytic synthesis of (S)-2, which have antitussive and antiemetic properties and relax the bronchial muscle, has been demonstrated by the novel rotatable composite design-based optimization method.
AtıfScopus3WoS3OpenAlex2İncele - MakaleAçık Erişim2025Scopus SJRQ3Phytochemical analysis and biological evaluation of essential oils and extracts from Heracleum pastinacifolium subsp. incanum (Boiss. & A.Huet) P.H.Davis, an endemic plant from Turkey
Yuca, Hafize; Sefalı, Abdurrahman; Aydın, Bilge; Karadayı, Mehmet; Gülşahin, Yusuf; Yazıcı, Ayşenur; Karakaya, Songül; Demirci, Betül; Çoban, Furkan; Özdemir, Erkan
Essential oil content of and phenolic compounds flower-fruit, root, and aerial parts of Heracleum pastinacifolium subsp. incanum were analysed by GC/MS and LC/MS methods, respectively. Antidiabetic, anticholinesterase, and antioxidant activities of flower-fruit, root, aerial parts methanol extracts were evaluated. Apiole (35.0%), myristicine (72.2%), and myristicine (15.1%) were found as major compounds of fruit-flower mixture, root, aerial part essential oils, respectively. Hesperidin was found the highest amount in aerial part and flower-fruit extracts with 8904.2621 ng/mL and 11558.3634 ng/mL values, respectively. Fruit-flower extract showed the highest activity against α-glucosidase (24%). Root extract demonstrating the highest activity (18%) against AChE enzyme. Flowers-fruits mixture methanol extract had a higher % inhibition value on ABTS·+ and DPPH•. Flowers-fruits mixture methanol extract was rich in total phenol, total tannin, and protein content. All the extracts were determined as genetoxically safe according to the results of Ames/Salmonella, Escherichia coli WP2 and Allium cepa assays.
AtıfScopus1WoS2OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ1FR2/mmWave, N258 and N261 Bands, 5G Frequency-Compatible Ultra-Thin Metamaterial Absorber with Polarization Insensitivity for EMI shielding Applications
Teber, Ahmet
Since adopting 5G technology, a notable rise in the prevalence of electromagnetic (EM) waves in the environment has become a significant concern. To reduce EM interference, broadband metamaterial absorbers offer an alternative solution for protecting devices in defense, communication, and healthcare applications, unlike their narrowband counterparts. This article presents a numerical investigation of an ultra-thin, polarization-insensitive metamaterial absorber (MMA) that uses metasurfaces and provides electromagnetic interference (EMI) reduction, covering the FR2/mmWave licensed N258 and N261 bands with an oblique incidence angle of up to 15 degrees. Comprehensive simulations are performed within the CST Studio Suite S2 2023 to examine the absorber's performance. Under normal incidence, the proposed MMA exhibits a wideband absorbency response exceeding 90% within the frequency range of 24.30–28.12 GHz. Moreover, the physical absorption mechanism is explained with electric and magnetic field distributions, including surface current distributions. Confirmation of the lack of mutual interaction among neighboring unit cells is established through testing with 1 × 2 and 2 × 2 arrays. An equivalent circuit model is also developed to confirm the EM simulation findings. The notable features of the proposed MMA make it an exceptional candidate for EM shielding applications, providing EMI reduction and covering the N258 and N261 bands.
AtıfScopus7WoS3OpenAlex5İncele - MakaleAçık Erişim2023Scopus SJRQ2Extended 2-D Magnetic Field Modeling of Linear Motor to Investigate the Magnetic Force Parameters of High-Speed Superconducting Maglev
Ozturk, Ufuk Kemal; Abdioglu, Murat; Ozkat, Erkan Caner; Mollahasanoglu, Hakki
A 2-D numerical finite-element model of a linear synchronous motor (LSM) is extended based on the magnetic field and moving mesh properties to investigate the magnetic flux and magnetic force characteristics of the high-speed electromagnetic levitation Maglev system, by using high-temperature superconductor (HTS) coils rather than lower current-carrying copper coils on the onboard unit and permanent magnets (PMs) on the ground. In this 2-D LSM model, the transient time-dependent solver is used to obtain the magnetic flux densities. Both the propulsion and levitation forces increased with increasing supercurrent Jc0 values indicating the advantage of using the superconducting windings in PM-LSM of Maglev vehicles as compared with the copper wires. It was also determined that, although the propulsion force is obtained on a comparable level with the studies in the literature, the lower levitation force issue than the electrodynamic suspension (EDS), despite the better propulsion to levitation force ratio, can be overcome by using the high flux trapping capacity bulk HTSs on the onboard unit together with the superconducting coils. The determined higher propulsion force in this PM-LSM Maglev model indicates that the Maglev vehicle can reach higher velocities in a short distance, and thus, this vehicle can be effectively used in short-distance travels in addition to the long-distance transportation. On the other hand, since the EDS system to be accelerated in a certain time interval via conventional wheels to achieve sufficient levitation, PM-LSM system can be integrated into the EDS Maglev system to ensure higher acceleration in a short time interval in addition to the higher levitation and propulsion force performances.
AtıfScopus10WoS10OpenAlex8İncele - MakaleAçık Erişim2024Scopus SJRQ3Machine learning driven optimization and parameter selection of multi-surface HTS Maglev
Ozkat, Erkan Caner; Abdioglu, Murat; Ozturk, U. Kemal
This research aims to tackle the challenges posed by precise force measurement for high temperature superconducting (HTS) Maglev systems, including mechanical constraints, step motor limitations, and sensor resolutions. For this aim, six machine learning (ML) models namely Support Vector Machine (SVM), Gaussian Process Regression (GPR), Extreme Gradient Boosting (XGB), Long Short-Term Memory (LSTM), Extreme Machine Learning (EML), and Convolutional Neural Network (CNN) were developed to predict levitation force (Fz) and lateral force (Fx) based on process parameters including permanent magnet width (PMW), field cooling height (FCH), the movement in the z-axis (vertical distance), and the movement in the x-axis (lateral distance). Among six ML models, CNN emerged as the most accurate model, demonstrating smaller root mean square deviation (RMSD) without compromising correlation coefficients. Furthermore, an innovative process window approach was introduced to select process parameters that simultaneously meet the minimum value of Fz and maximum value of Fx, named β1 and β2, set at 90 N and 0 N, respectively. Within this window, PMW of 30 mm and z values less than 10 mm were found to be consistent for all FCH and x values. The novelty of this study is to formulate the optimisation problem in HTS Maglev using the developed ML model by addressing two specific objectives one of which focuses on maximizing Fz while ensuring Fx remains within a defined tolerance (β3), representing the minimum allowable ratio of the levitation force to the total force, and the second problem aims to maximize Fz while obtaining zero Fx. The optimum PMW, FCH, x, and z values were obtained at 30 mm, 30 mm, 4 mm and 5 mm, corresponding to Fz and Fx values of 224.2 N and -53.8 N for option 1. As for option 2, the process parameters were obtained as 28.6 mm, 25.9 mm, 0 mm, and 5 mm, corresponding to Fz and Fx values of 194.2 N and 0 N. It was obtained both experimentally and by the optimization that Fz reaches close its maximum as the Fx gains attractive character. Hence, it is expected that the outcomes of this study will significantly benefit the design of HTS Maglev systems and find valuable applications across various transportation engineering projects.
AtıfScopus21WoS18İncele - MakaleYalnız künye2024Scopus SJRQ1Research of the crack problem of a functionally graded layer
Yaylacı, Murat; Yaylacı, Ecren Uzun; Turan, Muhittin; Özdemir, Mehmet Emin; Öztürk, Şevval; Ay, Sevil
In this study, the two-dimensional crack problem was investigated by using the finite element method (FEM)based ANSYS package program and the artificial neural network (ANN)-based multilayer perceptron (MLP) method. For this purpose, a half-infinite functionally graded (FG) layer with a crack pressed through two rigid blocks was analyzed using FEM and ANN. Mass forces and friction were neglected in the solution. To control the validity of the crack problem model exercised, the acquired results were compared with a study in the literature. In addition, FEM and ANN results were checked using Root Mean Square Error (RMSE) and coefficient of determination (R2), and a well agreement was found. Numerical solutions were made considering different geometric parameters and material properties. The stress intensity factor (SIF) was examined for these values, and the results were presented. Consequently, it is concluded that the considered non-dimensional quantities have a noteworthy influence on the SIF. Also FEM and ANN can be logical alternative methods to time-consuming analytical solutions if used correctly.
AtıfScopus27WoS30OpenAlex6İncele - MakaleYalnız künye2024Scopus SJRQ1Effective biocatalytic synthesis of enentiopure (R)-1,2-diphenylethanol as a pharmaceutical precursor using whole-cell biocatalyst
Çakmak, Fadile; Özdemir, Akın; Dertli, Enes; Şahin, Engin
Optically active alcohols are crucial precursors. 1,2-Diarylethanols and their analogues constitute a significant group of substances of biological significance. The biocatalytic synthesis of (R)-1,2-diphenylethanol ((R)-2), which can be utilized as a precursor to important drugs, is still not at the desired level in terms of substrate amount and production process. This study asymmetrically reduced 1,2-diphenylethanone (1) using the Lactobacillus paracasei BD87E6 biocatalyst and a novel orthogonal quadratic design-embedded optimization approach. The following reaction optimization conditions were determined using the suggested optimization technique: pH = 6, temperature = 31 °C, incubation period = 48 h, and agitation speed=134 rpm. In addition, the reaction conversion was estimated to be 99.38 %, and the product's enantiomeric excess (ee) was estimated to be 99.12 %. Further, (R)-2 was produced with >99 % ee, >99 % conversion, and 98 % yield in the experimental investigation under the established optimum conditions. This study is the first attempt to reduce substrate 1 to (R) or (S)-2 using a mathematical optimization method in the presence of a biocatalyst. Furthermore, on a high-gram scale, 1 (15.70 g) was entirely transformed into (R)-2 (15.54 g, 98 % isolated yield). Notably, this study is also the first to perform the gram-scale production of (R)-2 using a novel optimization approach and a biocatalyst. Finally, the innovative and novel orthogonal quadratic design-embedded optimization technique has been demonstrated as an efficient, cost-effective, and environmentally friendly biocatalytic procedure for synthesizing (R)-2.
AtıfScopus7WoS7OpenAlex6İncele - MakaleAçık Erişim2024Scopus SJRQ1Virtual Reality Technology in Nursing Education: A Qualitative Study
Avşar, Gülçin; Çelik, Şeymanur; Doğan, Sevgi; Çiftçi, Bahar
Virtual reality (VR) technology plays a significant role in nursing education by enhancing the quality of training by applying knowledge, decision-making, intervention completion and feedback. This study aims to examine nursing students' experiences and perceptions regarding the ventrogluteal injection training provided through VR technology. Conducted between May and June 2022, this qualitative descriptive phenomenology study took place at a state university in Turkey, involving 70 students who participated in Ventrogluteal Drug Administration training using VR glasses. The sample included 12 students selected via the Criterion Sampling Method. Data collection tools comprised the ‘Descriptive Information Form’ and a ‘Semi-Structured Questionnaire’. Qualitative data were analysed using the Content Analysis Method, while quantitative data were assessed through descriptive statistical methods (frequency, percentage, mean). The study identified 13 codes, four sub-themes and two main themes from the students' evaluations. The first main theme, ‘Weaknesses of Virtual Simulation’, included two sub-themes: ‘Due to its Nature’ and ‘Due to its Technique’, resulting in five codes. The second main theme, ‘Strengths of Virtual Simulation’, was divided into two sub-themes: ‘Permanence, Integrity, and Applicability’ and ‘Emotions towards Virtual Simulation’, with eight codes identified. The findings indicate that students view VR technology positively in their education. However, they also highlighted specific issues related to the simulation's technique and inherent nature.
AtıfScopus5WoS4OpenAlex6İncele
