Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(116)
- Şahin, Engin(48)
- Kaya, Yunus(46)
- Özen, Soner(46)
- İspirli, Hümeyra(45)
- Pat, Suat(44)
- Şenay, Volkan(42)
- Korkmaz, Şadan(36)
- Yilmaz, Mustafa Tahsin(33)
- Kutlu, Naciye(32)
- Cuce, Erdem(31)
- Öner, Erdal(31)
- Artar, Musa(30)
- Ertugrul, Mehmet(29)
- Hasar, Ugur Cem(29)
- Mercan, Emin(28)
- Bayraktar, Bülent(27)
- Bayram, Sinan(27)
- Can, Zehra(25)
- Ecem Bayram, Nesrin(25)
- Çolak, Murat(23)
- Özdemir, Akın(23)
- Cuce, Pinar Mert(22)
- Sert, Durmuş(22)
- Ayata, Ümit(21)
- Bayram, Ozkan(21)
- Dirican, Ebubekir(20)
- Abdioglu, Murat(19)
- Ayazoglu, Rabil(19)
- Birinci, Ahmet(19)
- Kamiloğlu, Aybike(19)
- Gerçek, Yusuf Can(18)
- Taylan, Osman(18)
- Tozlu, Alperen(18)
- Gul, Volkan(15)
- Hasar, Ugur C.(15)
- Kadakal, Mahir(15)
- Sagdic, Osman(15)
- Ergün, Mustafa(14)
- Kadakal, Huriye(14)
Yayınlar
- MakaleAçık Erişim2024Scopus SJRQ1Optimization of mechanochemical surface modification parameters on planetary mill using an I-optimal experimental design
Özdemir, Akın; Uçurum, Metin
Several micro-particle-size additives and filler minerals are added to many industrial products, especially plastic, in order to reduce cost and improve mechanical properties and appearance. Also, grinding and surface modification are two fundamental properties of the filler minerals used in plastic products. Notably, Bayburt stone (BS) used as a natural raw material from Bayburt, Türkiye contains 76% SiO2 and 15% Al2O3. In this paper, the hydrophilic surface structure of micronized Bayburt stone (MBS) was made hydrophobe by mechanochemical surface modification using calcium stearate [Ca(C17H35COO)2] in a laboratory-type planetary mill. Next, the optimum conditions of the surface modification design factors, which are (1) ball filling ratio = 30.53%, (2) powder filling ratio = 10.43%, (3) mill speed = 475.91 rpm, (4) chemical dosage = 1.99% of powder, and (5) modification time = 4.83 min., were obtained using the proposed I-optimal design-focused optimization model when predicting the model parameters. In addition, a coated micronized Bayburt stone (CMBS) product with an active ratio (AR) of 99.90% and d10, d50, and d90 values of 1.32 μm, 3.48 μm and 9.55 μm were achieved. Finally, particle size distribution (PSD), thermo-gravimetric and differential thermal analyzer (TG-DTA), Fourier transform infrared (FTIR), scanning electron microscope (SEM), electron dispersive spectrum (EDS), and contact angle analyses were performed on the CMBS product.
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İncele - MakaleAçık Erişim2024Scopus SJRQ4Bibliometric Analysis of Sport Entrepreneurship Literature: The Case of Web of Science; [Spor Girişimciliği Literatürünün Bibliyometrik Analizi: Web of Science Örneği]
Esmer, Yusuf; Dertli, Şükran
Sport entrepreneurship is the sport dimension of entrepreneurship and research on the concept has increased in recent years. The aim of this research is to provide a general perspective on sports entrepreneurship, to draw attention to the importance of the subject and to generate ideas for further research. For this purpose, bibliometric analysis technique was used in the research. In this context, 494 publications on sport entrepreneurship in the WoS database were examined under 7 headings (advanced search, cited references, co-author analysis, common word analysis, citation analysis, bibliometric matching analysis, co-citation analysis). These titles were analyzed in a total of 32 parameters and analyzed bibliometrically with Sankey diagram, VOSviewer, MapChart and Wordclouds programs. When the researches on sports entrepreneurship were examined, it was determined that the most publications were made in 2020 and the most citations were made in 2021, and the title, keyword, abstract, research area and WoS categories specified in the publications were related to each other. In this context, it has been seen that the basis of the structure in the relevant literature is sports, entrepreneurship, management, business and innovation. Although bibliometric studies have been conducted in the field of entrepreneurship in national literature, bibliometric analysis of sports entrepreneurship has not been carried out in a comprehensive manner, the number of studies in the international literature is low, and the use of more parameters and more data in this research than the studies conducted in the international literature reveals the importance and originality of the research.
AtıfScopus2WoS1OpenAlex1İncele - MakaleAçık Erişim2024Scopus SJRQ1Assessment of Different Methods for Estimation of Missing Rainfall Data
Hırca, Tuğçe; Eryılmaz Türkkan, Gökçen
Missing data is a common problem encountered in various fields, including clinical research, environmental sciences and hydrology. In order to obtain reliable results from the analysis, the data inventory must be completed. This paper presents a methodology for addressing the missing data problem by examining the missing data structure and missing data techniques. Simulated datasets were created by considering the number of missing data, missing data pattern and missing data mechanism of real datasets containing missing values, which are often overlooked in hydrology. Considering the missing data pattern, the most commonly used methods for missing data analysis in hydrology and other fields were applied to the created simulated datasets. Simple imputation techniques and expectation maximization (EM) were implemented in SPSS software and machine learning techniques such as k-nearest neighbor (kNN), together with the hot-deck were implemented in the Python programming language. In the performance evaluation based on error metrics, it is concluded that the EM method is the most suitable completion method. Homogeneity analyses were performed in the Mathematica programming language to identify possible changes and inconsistencies in the completed rainfall dataset. Homogeneity analyses revealed that most of the completed rainfall datasets are homogeneous at class 1 level, consistent and reliable and do not show systematic changes in time.
AtıfScopus22WoS23OpenAlex27İncele - MakaleAçık Erişim2024Scopus SJRQ1Evaluation of Dynamic and Fatigue Behavior of Damaged Steel Beams Strengthened with Different Types of Techniques and a New Strengthening Method Proposal
Ergün, Mustafa; Ateş, Şevket
In recent years, the use of carbon fiber-reinforced polymers to strengthen fatigue-damaged steel beams has increased significantly as an alternative to traditional methods due to their easy application to the damaged area, lightweight, durability, and sustainability. In addition to all these positive contributions, there are some disadvantages, such as debonding damage under loading. These disadvantages encourage researchers to produce new materials or apply materials used for other purposes in other fields for fatigue damage. In this paper, an alternative new strengthening technique is mentioned to improve the dynamic and fatigue behavior of fatigue-damaged steel beams. This technique is a strengthening application made using epoxy-based filler and carbon fiber-reinforced polymer fabric. Numerical and experimental studies are carried out on fatigue-damaged steel beams by applying this new technique and using different carbon fiber-reinforced polymers, such as a single and double layer of fabric and a single plate layer. The most significant improvement in dynamic behavior occurred on the specimen, strengthened with this newly proposed technique. In contrast, the lowest increase occurs on the sample strengthened with a single layer of fabric. While the lowest increase arises on the sample strengthened with a single layer of fabric in terms of fatigue life, the most significant progress in fatigue behavior makes on the sample strengthened with a single plate layer. As a result of comparing the results, it is concluded that this new strengthening technique could be an essential alternative to the currently used strengthening methods.
AtıfScopus2WoS2OpenAlex3İncele - MakaleYalnız künye2024Scopus SJRQ4Earthquake convexity and some new related inequalities
Kadakal, Mahir; Işcan, Imdat; Kadakal, Huriye
Unfortunately, eleven of our provinces were severely affected due to two severe earthquakes that occurred in our country, the Republic of Turkey, on February 6, 2023. As a result, thousands of buildings were destroyed and tens of thousands of our citizens lost their lives. From past to present, such disasters have occurred in many parts of our world and will continue to happen. In order to raise awareness for researchers and academicians reading our article, we will give a new definition of convexity in this article, and we will call it "earthquake convexity". In this paper, we study some algebraic properties of the earthquake convexity. Then we compare the results obtained with both Hölder, Hölder-Işcan inequalities and power-mean, improved power-mean integral inequalities and show that the results obtained with Hölder-Işcan and improved power-mean inequalities are better than the others. Some applications to special means of real numbers are also given.
AtıfWoS1OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ1Evaluation of lavender essential oils and by-products using microwave hydrodistillation and conventional hydrodistillation
Kırkıncı, Seran; Gercek, Yusuf Can; Baştürk, Fatma Nur; Yıldırım, Nazlıcan; Gıdık, Betül; Bayram, Nesrin Ecem
This study investigated the impact of two extraction methods, traditional hydrodistillation (TDH) and microwave-assisted hydrodistillation (MAH), on the essential oil yield and chemical profile of Lavandula angustifolia L., as well as the bioactive potential of the resulting wastewater. Essential oil composition was analyzed via GC–MS, revealing similar qualitative and quantitative profiles for both methods, with α-terpinolene and (–)borneol as major constituents. Wastewater analysis via LC–MS/MS and spectrophotometric assays demonstrated the presence of significant total phenolic content (3.29–1.78 mg GAE/g) and 32 individual phenolics (463.1 µg/kg for TDH; 479.33 µg/kg for MAH). These findings suggest that both essential oil and wastewater obtained by either method possess considerable bioactive potential, with the MAH method potentially offering advantages over TDH for essential oil extraction. Further exploration of wastewater applications in various industrial sectors is warranted.
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İncele - MakaleAçık Erişim2024Scopus SJRQ2Exploring alternative polymer materials for joint liners: a software-guided material selection
Yilmaz, Galip; Gerdan, Zeynep; Çolak, Murat
This study explores the alternative polymer materials and selection process for joint implant liners, focusing on applying CES Selector software to identify suitable polymer materials. CES Selector provides an easy-to-use interface. It offers multiple selection methods, including boundary values and property constraints. Seven materials were excluded from the analysis, resulting in 19 potential candidates, including unconventional options like EVOH, PCTA, PESU, PI, PPA, PPC, PPSU, and PSU. The materials underwent evaluation based on key criteria, including tensile strength, Young’s modulus, compressive strength, fatigue strength, and fracture toughness. Overall, TPU exhibited a remarkable combination of high mechanical strength and adaptable Young’s modulus, making it a top contender. However, in other evaluation criteria, PI surpassed TPU, solidifying its potential as a superior choice. This systematic approach provides valuable insights for engineers and designers seeking innovative materials for joint implant liners. The study results broaden the range of materials used in implant manufacturing, providing potential alternatives that offer better long-term durability and performance.
- MakaleAçık Erişim2024Scopus SJRQ2Foundational Engineering of Artificial Blood Vessels’ Biomechanics: The Impact of Wavy Geometric Designs
Yilmaz, Galip
The design of wavy structures and their mechanical implications on artificial blood vessels (ABVs) have been insufficiently studied in the existing literature. This research aims to explore the influence of various wavy geometric designs on the mechanical properties of ABVs and to establish a foundational framework for advancing and applying these designs. Computer-aided design (CAD) and finite element method (FEM) simulations, in conjunction with physical sample testing, were utilized. A geometric model incorporating concave and convex curves was developed and analyzed with a symbolic mathematical tool. Subsequently, a total of ten CAD models were subjected to increasing internal pressures using a FEM simulation to evaluate the expansion of internal areas. Additionally, physical experiments were conducted further to investigate the expansion of ABV samples under pressure. The results demonstrated that increased wave numbers significantly enhance the flexibility of ABVs. Samples with 22 waves exhibited a 45% larger area under 24 kPa pressure than those with simple circles. However, the increased number of waves also led to undesirable high-pressure gradients at elevated pressures. Furthermore, a strong correlation was observed between the experimental outcomes and the simulation results, with a notably low error margin, ranging from 19.88% to 3.84%. Incorporating wavy designs into ABVs can effectively increase both vessel flexibility and the internal area under pressure. Finally, it was found that expansion depending on the wave number can be efficiently modeled with a simple linear equation, which could be utilized in future designs.
AtıfScopus2İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1Meditating role of career sustainability in the relationship between teachers’ self-efficacy and job satisfaction and subject well-being
Özbilen, Uğur; Güven, Ahmet Zeki; Yiğit, Ömer; Kara, Ömer Tuğrul; Banaz, Emrullah
The main purpose of this study, explore the mediating role of career sustainability in the relationships between teacher self-efficacy, job satisfaction, and subjective well-being. Teachers should have an acceptable level of satisfaction regarding self-efficacy, career sustainability, and job satisfaction to secure well-being. In a sense, this claim mandates revealing the relationships between these variables. Accordingly, we collected data from 369 Turkish language teachers aged 24–55 years employed in public schools using the Teacher Self-Efficacy Scale, Short Index of Job Satisfaction, Career Sustainability Scale, and Subjective Well-Being Scale and tested a mediation model to seek answers to our hypotheses. We collected the data using an online questionnaire battery web-based survey (Google Forms) which was created using data collection measures and demographic items. After creating the survey using Google Forms, we distributed it through various channels such as email lists, social media platforms, and professional networks (e.g., teacher WhatsApp groups, teacher Telegram groups, etc.). Respondents were invited to participate in the survey voluntarily. The findings showed that career sustainability mediated the relationships between teacher self-efficacy, job satisfaction, and subjective well-being. Accordingly, we may claim that teachers with desirable career sustainability are likely to have increased job satisfaction and well-being, contributing to their self-efficacy. This research emphasises the essential significance of career sustainability in the overall well-being and work satisfaction of teachers. Future study should investigate treatments aimed at improving career sustainability and examine these linkages in other cultural settings.
AtıfScopus8WoS7OpenAlex12İncele - MakaleAçık Erişim2024Scopus SJRQ2Multilocus sequence typing of L. bulgaricus and S. thermophilus strains from Turkish traditional yoghurts and characterisation of their techno-functional roles
Dikmen, Hilal; Goktas, Hamza; Demirbas, Fatmanur; Kayacan, Selma; Ispirli, Humeyra; Arici, Muhammet; Turker, Mustafa; Sagdic, Osman; Dertli, Enes
In this study, Streptococcus thermophilus and Lactobacillus bulgaricus strains from traditional Turkish yoghurts were isolated, identified by 16S rRNA sequencing and genotypically 14 S. thermophilus and 6 L. bulgaricus strains were obtained as distinct strains by MLST analysis. Lactic acid production levels of the L. bulgaricus strains were higher than S. thermophilus strains. HPLC analysis showed that EPS monosaccharide composition of the strains mainly consisted of glucose and galactose. In general, all strains were found to be susceptible for antibiotics, except some strains were resistance to gentamicin and kanamycin. Apart from two strains of S. thermophilus, all strains displayed strong auto-aggregation level greater than 95% at 24 h incubation. S. thermophilus strains showed higher cell surface hydrophobicity than L. bulgaricus strains. This study demonstrated the isolation, identification, genotypic discrimination and techno-functional features of wild type yoghurt starter cultures which can potentially find place in industrial applications.
AtıfScopus6WoS5OpenAlex6İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ2Generalized strongly n-polynomial convex functions and related inequalities
Özcan, Serap; Kadakal, Mahir; İşcan, İmdat; Kadakal, Huriye
This paper focuses on introducing and examining the class of generalized strongly n-polynomial convex functions. Relationships between these functions and other types of convex functions are explored. The Hermite–Hadamard inequality is established for generalized strongly n-polynomial convex functions. Additionally, new integral inequalities of Hermite–Hadamard type are derived for this class of functions using the Hölder–İşcan integral inequality. The results obtained in this paper are compared with those known in the literature, demonstrating the superiority of the new results. Finally, some applications for special means are provided.
AtıfScopus5WoS5OpenAlex6İncele - MakaleAçık Erişim2024Scopus SJRQ1Evaluation of nurses’ attitudes and behaviors regarding narcotic drug safety and addiction: a descriptive cross-sectional study
Kaya, Ayten; Kirbaş, Zila Özlem; Medin, Suhule Tepe
Background: By evaluating nurses’ attitudes and behaviors regarding narcotic drug safety and addiction, effective strategies need to be developed for combating addiction in healthcare institutions. This study, aimed at providing an insight into patient and staff safety issues through the formulation of health policies, aimed to evaluate nurses’ attitudes and behaviors regarding narcotic drug safety and addiction. Methods: The study was conducted in a descriptive cross-sectional design. It was carried out with 191 nurses in a public hospital between March 2023 and August 2023. Data were collected through face-to-face interviews, gathering socio-demographic information and utilizing the Addictive Substance Attitude Scale. The data were analyzed using independent sample t-tests, one-way ANOVA tests, and regression analysis (P <.001 and p <.05). Results: The average age of the participants was determined to be 36.58 ± 8.40. It was reported by 85.3% of nurses that narcotic drug follow-ups in their units were conducted according to procedures. In the study, it was found that 63.9% of nurses did not know the procedure to be followed towards a healthcare professional identified as a narcotic substance addict. The total mean score of the Addictive Substance Attitude Scale of nurses participating in the study was 74.27 ± 14.70. A significant difference was found between the total scores of the scale and the level of education of nurses, the follow-up status of the drugs in the unit where they work, their status of receiving narcotic drug addiction training, and their routine use of the half-dose drug disposal form (p <.05). Conclusions: The findings of this study underscore the importance of evaluating nurses’ attitudes and behaviors regarding narcotic drug safety and addiction. These results indicate the need for nursing administrators, particularly in terms of patient and staff safety, to adopt more effective policies and strategies.
AtıfScopus1WoS1OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ2Niobium modification on dielectric, magnetic and structural features of nanocrystalline Ni–Co ferrites
Teber, Ahmet; Sarac, Mehmet Fahri
In this study, we will investigate the structural, characteristic, dielectric and magnetic features of Co0.5Ni0.5Nb xFe2–xO4 (0.0 ≤ x (with 0.2 increments) ≤ 1.0) nanoparticles, which are prepared via the hydrothermal approach. M-type hexagonal crystal structures are confirmed through XRD, FT-IR, SEM-EDS, TEM-SAED and VSM. Also, we have reported the investigations on dielectric properties and ac conductivity. Based on XRD measurements, it is concluded that all samples have M-type hexagonal crystal structure with nanocrystals ranging from 60 to 97 nm. The diffraction patterns obtained matched well with the calculated patterns from Rietveld analysis. Moreover, from the morphological analysis, it was observed that the small spherical structures of Ni–Co ferrite particles transformed into quadrilateral structures with increasing Nb concentration. The results of the FT-IR study show that the hexaferrite structure is formed as predicted because the expected range of absorption bands is present. According to VSM, Nb-substituted Ni–Co ferrite nanostructures reveal a relatively soft ferromagnetic property. Increasing the concentration of Nb tends to increase the coercive field (H c) variation. The dielectric factors and ac conductivity were measured in the frequency range of 0.1–10 MHz. The reduction in dielectric factors and tangent losses at low frequencies can be elucidated by both deformation and relaxation polarization mechanisms. Another observation is that ac conductivity is amplified with the applied frequency. In this sense, the electron and hole hopping phenomenon can explain the conduction mechanism.
- MakaleYayıncıda açık erişim2024Scopus SJRQ1Multi-method examination of contact mechanics in orthotropic layers under gravity
Öner, Erdal; Uzun Yaylacı, Ecren; Yaylacı, Murat
Analyzing the behavior of intelligent unconventional materials under diverse contact scenarios, in comparison to conventional materials, is a critical step in the initial design of engineering systems. This paper presents the development of analytical and numerical approaches for analyzing contact mechanics in a system comprising an orthotropic layer resting on a rigid foundation. Parametric analyses include the consideration of cylindrical and flat punch profiles. Analytical formulation utilizes integral transform methods to convert planar elasticity equations into a Cauchy-type singular integral equation of the second kind. A detailed description of the solution technique for the integral equation is provided, encompassing both the analytical formulation and the required discretization for obtaining the solution. Subsequently, a finite element approach (FEA) is employed to approximate contact bodies using a collection of finite elements, while contact boundaries are approximated by utilizing a set of polygons. Alternatively, the problem is addressed using the Multilayer Perceptron approach, a form of artificial neural network frequently applied in diverse machine learning applications, including scenarios involving contact problems. Finally, the resolution to the problem is achieved by employing the multilayer perceptron (MLP) method. The study yields determinations of contact stresses under the punch, the critical separation load resulting in the detachment of the orthotropic layer from the rigid foundation, and the corresponding separation distance. This analysis considers a range of dimensionless parameters and explored the behavior of diverse orthotropic materials. Comparisons between the results of the analytical method and computations from FEA and MLP reveal the exceptional accuracy attained by all three approaches. As the pioneer study employing three distinct approaches to examine continuous contact mechanics within an orthotropic layer under the influence of gravity, this research constitutes a valuable point of reference for upcoming scholars in the field.
AtıfScopus50WoS53OpenAlex44İncele - MakaleAçık Erişim2024Scopus SJRQ3Change in Wood Color Due To The Use of Waste Vegetable Oils
Ayata, Ümit
An investigation was carried out without the use of thermal treatment to determine whether waste oils have color-altering effects on wood material surfaces. Waste vegetable oils (walnut, sunflower, corn, and olive) were applied to the surfaces of wood materials from ayous (Triplochiton scleroxylon K. Schum), fukadi (Terminalia amazonia), guatambú (Balfourodendron riedelianum (Engl.) Engl.), mahogany (Swietenia mahagoni (L.) Jacq.), and rengas (Gluta renghas L.) tree species. Subsequently, a control group was established, and experimental samples were compared. Changes in color parameters (L*, ∆a*, C*, ∆L*, a*, ∆b*, ho, ∆H*, b*, ∆C*, and ∆E*) were investigated. The results of multivariate analysis of variance for color parameters (C*, ho, L*, a*, and b*) were found to be statistically significant. A decrease in ho and L* was observed for all wood types and waste oils. On the other hand, a* and b* values increased and C* values decreased in guatambú and ayous wood on application of all waste vegetable oils. However, in the case of mahogany and rengas wood, a* and b* values decreased while C* values increased.
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2024Scopus SJRQ1De-Embedding Technique for Parameter Extraction of Biaxial Bianisotropic Metamaterial Slabs
Hasar, Ugur Cem; Kaya, Yunus; Korkmaz, Huseyin; Iliev, Teodor
Among material classes of isotropic, anisotropic, bi-isotropic, and bianisotropic, the latter class is important because, as different from other classes, the bianisotropic class can describe complex behavior of various materials through tensor expressions between electric and magnetic fields via electric and magnetic flux densities. All electromagnetic parameters (a total of seven) of a general bianisotropic material need to be accurately extracted for understanding its response and characteristic. Extraction methods can be utilized for such a goal. However, the extraction methods in the literature either require a formal calibration procedure or are limited to the extraction of three electromagnetic parameters only. In this study, an attractive self-calibrating waveguide method has been devised for determination of electromagnetic parameters of biaxial biansiotropic metamaterial (MM) slabs. Its first advantage is that it uses a thru connection in addition to the MM-loaded line connection (three different configurations - Case A, Case B, and Case C) and empty-line connection next to the MM-loaded line connection to extract all (seven) constitutive parameters together with the magnetoelectric coupling coefficient. Its second advantage is that it relies on explicit expressions and does not require any calibration process for such an extraction. Simulations and uncalibrated scattering parameter waveguide measurements at X-band (8.2 - 12.4GHz) were performed for a biaxial bianisotropic MM slab made by C-patterned resonators to validate the proposed method. It is observed that extracted electromagnetic parameters by the proposed method satisfy the passivity conditions over the entire frequency band except for a few frequency points or regions (e.g., f = 8.2 GHz). Its reason is expected to be associated with the difficulty in satisfying the continuous medium property at such frequencies. Besides, it is noted that two of the constitutive parameters (ɛ 2 and μ3) illustrate a thickness-resonance behavior revealed by additional measurements of the Case B - MM structure with different lengths (7.675 mm, 9.21 mm, and 10.475 mm). Besides, it is noted that the resonance behavior of the Case C - MM structure changes with a change in periodicity. Specifically, when the periodicity in the x direction of this MM structure changes from approximately 3.26 mm to 2.29 mm, the resonance frequency shifts from nearly 10.43 GHz to 10.30 GHz (a 1.25% variation). Finally, sensitivity, uncertainty, and error analyses were also performed to evaluate and improve its accuracy. It is observed that |3/Λ 1A| | is 14 times greater than | xi 0 / Λ 1A| | at 10.85 GHz where Λ 1A is one of the terms related to measured S-parameters for the Case A - MM structure, and |∗ | denotes the magnitude of the complex number ∗
AtıfScopus1WoS1OpenAlex1İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ2Nonlinear optical properties of KnCl (n = 2-7) superalkali clusters
Şentürk, Şükrü; Fardad, Fraidoon; Ekincioğlu, Yavuz
The lowest energy structures along with the low lying isomer, stabilities, electronic properties, optical properties and nonlinear optical responses of KnCl (n = 2-7) clusters were studied within the density functional theory. The second order energy difference, dissociation energy and GH-L (HOMO-LUMO gap) point out that KnCl (n = 3, 5, 7) clusters are more stable. The calculated adiabatic ionization energies (AIE) for the KnCl (n = 2-6) clusters are in agreement with the measured ionization energies. The optical properties, namely optical electronegativity and refractive index, depends on the GH-L energy values. The K atom capped planar rhombus geometry of the K4Cl causes the noticeable vibrational frequency shift compared to the rest of IR spectra of the clusters. The first static hyperpolarizability (β o) values are in the range of 2.33 × 103-2.87 × 104 au and the second static hyperpolarizability varies between 5.74 × 106 au and 38.9 × 106 au for the cluster. The nonlinear optical response is due to the superalkali nature of KnCl (n = 2-7) clusters. From computed β vec values, the hyperpolarizability has projection on the dipole moment vector for the superalkalis except the K2Cl and K5Cl. The absorption spectra point out that KnCl (n = 6-7) clusters can be suitable as a NLO material since they have transparency in the deep UV region (λ< 300 nm).
AtıfScopus2WoS2OpenAlex3İncele - MakaleAçık Erişim2024Scopus SJRQ3Investigation of Microbiological, Physiological and Histopathological Changes in Polymicrobial Infection in Old Rats
Ülker, U.; Kızıl, S.; Bayraktar, B.; Alçığır, M.E.; Kul, O.; Kaya, H.; Ürüşan, H.; Aydemir, Ş.; Kotan, G.C.; Önel, A.U.
Background: The aim of this study is to examine the microbiological, clinical, physiological and pathological findings of natural polymicrobial infection developing in a wistar rat colony under long-term observation. Methods: In this study, 70 male Wistar albino rats, 3 years old, raised by conventional methods and housed in a cage environment were used. Thirteen rats with clinical symptoms such as torticollis and rotation were sacrificed for microbiological and histopathological examination after 14 days. For microbiological examination, the rapid diagnostic kit BBL Crystal system was used to identify bacterial agents in tissue and stool samples and the traditional culture method was used for isolation. Result: As a result of microbiological analysis, the rarely isolated Staphylococcus capitis (S. capitis) was isolated. Different Staphylococcus spp. It has been determined that the species can cause suppurative meningoencephalitis as well as septicemia in the brains of experimental animals., it is thought that polymicrobial infection will be useful for the identification of bacterial agents and infection prevention and treatment strategies.
- MakaleAçık Erişim2024Scopus SJRQ2Optimization of a Novel–Enriched Pasta Production and Its Physical, Chemical, and Characteristic Properties
Yilmaz, Merve Silanur; Kutlu, Naciye; Sakiyan, Ozge; Isci, Asli
The aim of the study is to enrich pasta with cornelian cherry powder, a product with high bioactive contents. In this way, it was aimed to obtain a new product that is more nutritionally advanced and can contribute to the country’s economy. In this study, cornelian cherry with high bioactive content and an attractive color advantage was used for the enrichment of the pasta formulation. In addition, the pasta production procedure was revised by applying microwave technology for drying. Cornelian cherry powder:dough ratio, dough thickness, and microwave power were optimized with response surface methodology. Total phenolic content, antioxidant activity, color, and water-holding capacity were determined as responses. Optimum conditions were found as 4.53% for powder:dough ratio, 0.1 cm for dough thickness, and 270 W for microwave power. According to optimization results, it was detected that the cornelian cherry powder:dough ratio affected the total phenolic content and antioxidant activity, and microwave power was found to be effective only on antioxidant activity. For optimum conditions, the total phenolic content and antioxidant activity were found as 1.29 GAE/g and 0.5 mg TE/g, respectively. The characterization analysis showed that the microwave–dried sample shrank less than those dried with the conventional method. In Fourier transform infrared spectroscopy (FTIR) results, it was determined that the amount of carbohydrates in the samples obtained under optimum conditions was lower than that of control. It has been observed that the application of microwave technology for drying pasta enriched with cornelian cherry powder had positive effects on the quality of the final product.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2024Scopus SJRQ1A case study comparing seismic retrofitting techniques for a historically significant masonry building's minaret
Kiral, Adnan; Ergün, Mustafa; Tonyali, Zeliha; Artar, Musa; Şentürk, İdris
Historical masonry structures are extremely susceptible to earthquakes due to their characteristic features. Seismic performance and corresponding damage patterns vary between these buildings. Even though the main structure was undamaged, many minarets suffered damage or collapsed due to the transmission of large forces from the main mass to the minaret and the abrupt changes in cross-section due to the geometry of the minaret. This study uses an ancient masonry mosque as a case study, whose minaret and main building are constructed as a single structure. The mosque's minaret under seismic excitation is the focus of this study. The adopted model is called Alaeddin Bey Mosque in Muş, Türkiye. The seismic performance assessment of the minaret, considering various retrofitting options, is mainly based on four critical parameters: base shear, acceleration, displacement, and maximum tensile forces in all three dimensions. The analyzed retrofitting methods include base isolation located in the basement of the mosque, viscous dampers placed only in the upper part of the minaret, Carbon Fiber-Reinforced Polymer fabric fitted to only the minaret, and steel plates applied to only the minaret. Representative structural models of the mosque have been modelled with SAP2000 software. The main novelty of this study is the use of viscous dampers in the minaret. It is the first time a design methodology has been introduced for viscous damper applications in minarets. This methodology aims to prevent local damage to the minaret due to the forces generated by the dampers, while also considering the constraints of limited internal space within the minaret. The finding of this study shows that viscous damper application yields significantly better results compared to the application of Carbon Fiber-Reinforced Polymer fabric and steel plates. However, although base isolation reduces the tensile stress values throughout the entire mosque to levels well below the material's strength, viscous damper application in the minaret significantly reduces tensile stresses only in the minaret. As a result, viscous dampers are recommended for damage reduction in the minaret only. Otherwise, base isolation should be considered for reducing stress values throughout the entire mosque including the minaret. This study contributes towards the development of new seismic retrofitting methods for historic masonry buildings ‘minaret.
AtıfScopus26WoS26OpenAlex24İncele