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Article Citation - WoS: 16Citation - Scopus: 17Keggin Type-Polyoxometalate Decorated Ruthenium Nanoparticles: Highly Active and Selective Nanocatalyst for the Oxidation of Veratryl Alcohol as a Lignin Model Compound(Wiley-v C H verlag Gmbh, 2017) Baguc, Ismail Burak; Saglam, Serif; Ertas, Ilknur Efecan; Keles, Muhammed Nuri; Celebi, Metin; Kaya, Murat; Zahmakiran, MehmetDescribed herein is a new nanocatalyst system that efficiently works in the aerobic oxidation of veratryl alcohol (VA), which is formed by cleavage of beta-O-4 linkages in lignin, to veratraldehyde (VAL) under mild reaction conditions. The new nanocatalyst system comprised of ruthenium(0) nanoparticles supported on the Keggin type polyoxometalate (POM; K-3[PMo12O40]) network (Ru/POM) can simply and reproducibly be prepared by the dimethylamine-borane ((CH3)(2)NHBH3) reduction of ruthenium(III) chloride trihydrate (RuCl3.3H(2)O) in isopropanol solution of K-3[P Mo12O40] at room temperature. The characterization of Ru/POM by the combination of various analytical techniques reveals that the formation of well-dispersed ruthenium(0) nanoparticles with a mean diameter of 4.7 +/- 1.2nm on the surface of POM network structure. This new Ru/POM nanocatalyst displays remarkable activity (TOF=7.5mol VAld/mol Ru x h) at high selectivity (> 98%) and almost complete conversion (98%) in the aerobic oxidation of VA to VAld under mild conditions.Article Citation - WoS: 4Citation - Scopus: 3The Euler-Lagrange Theory for Schur's Algorithm: Wall Pairs(Academic Press inc Elsevier Science, 2006) Khrushchev, SThis paper develops a techniques of Wall pairs for the study of periodic exposed quadratic irrationalities in the unit ball of the Hardy algebra. (C) 2005 Elsevier Inc. All rights reserved.Article Citation - WoS: 3Evaluation of the Effects of Avatar on Learning Temporomandibular Joint in a Metaverse-Based Training(Wiley, 2024) Basmaci, Fulya; Bulut, Ali Can; Ozcelik, Erol; Ekici, Saliha Zerdali; Kilicarslan, Mehmet Ali; Cagiltay, Nergiz ErcilPurposeAvatars, representing users in the digital world, can influence users' behavior and attitudes. This study evaluates the impact of representing dental students receiving temporomandibular joint (TMJ) education in the metaverse via an anonymous or identified avatar.MethodsParticipants included 80 dental students in their fourth and fifth years of study. They were randomly assigned to either the avatar group (identified avatar) or the control group (anonymous avatar). Prior to training, participants completed a demographic questionnaire and a pretraining knowledge assessment. TMJ training was conducted in the metaverse for both groups. Pre- and post-training assessments included the Spielberger State-Trait Anxiety Inventory and a shyness scale to ensure group comparability. A post-test consisting of five questions was administered to both groups after 2 weeks of training.ResultsThere were no significant differences in pretraining scores for prior knowledge (p = 0.67), trait anxiety (p = 0.28), state anxiety (p = 0.92), or shyness (p = 0.42) between the avatar and control groups, indicating comparability at baseline. Post-training analysis revealed significantly higher post-test scores in the avatar group (median = 80) compared to the control group (median = 60) (p = 0.03).ConclusionsMetaverse environments offer various benefits for students, educators, and educational institutions in health education programs. Representing learners and their identities in training environments can enhance learning outcomes.Article Citation - WoS: 14Citation - Scopus: 15Yielding of Two-Layer Shrink-Fitted Composite Tubes Subject To Radial Pressure(Springer Heidelberg, 2005) Eraslan, AN; Akis, TYielding of two-layer shrink-fitted composite tubes with axially constrained ends subject to either internal or external pressure is investigated in detail. In the framework of small deformations, a state of plane strain and von Mises yield criterion, analytical expressions are obtained for critical values of the pressure leading to plastic flow. It is shown that, depending on material properties and tube dimensions, different modes of plastic deformation may occur. Yielding may commence at the inner tube or at the outer tube or simultaneously in both tubes. The conditions for different nature of plastic flow are determined. Using analytical expressions obtained for critical values of the parameters and properties of real engineering materials, various numerical examples are handled and the variation of elastic limit pressure with interference and interface radius is explained.Article Citation - WoS: 4Citation - Scopus: 4Multiloop State-Dependent Nonlinear Time-Varying Sliding Mode Control of Unmanned Small-Scale Helicopter(Sage Publications Ltd, 2020) Ozcan, Sinan; Salamci, Metin U.; Nalbantoglu, VolkanTime delays, parameter uncertainties, and disturbances are the fundamental problems that hinder the stability and reduce dramatically the tracking performance of dynamical systems. In this paper, a new state-dependent nonlinear time-varying sliding mode control autopilot structure is proposed to cope with these dynamical and environmental complexities for an unmanned helicopter. The presented technique is based on freezing the nonlinear system equations on each time step and designing a controller using the frozen system model at this time step. The proposed method offers an improved performance in the presence of major disturbances and parameter uncertainties by adapting itself to possible dynamical varieties without a need of trimming the system on different operating conditions. Unlike the existing linear cascade autopilot structure, this study also proposes a nonlinear cascade state-dependent coefficient helicopter autopilot structure consisting of four separate nonlinear sub-systems. The proposed method is tested through the real time and PC-based simulations. To show the performance of the proposed robust method, it is also bench-marked against a linear sliding control control in PC-based simulations.Article Citation - WoS: 5On Some Fixed Point Results in Extended Strong b-spaces(int Center Scientific Research & Studies, 2018) Alqahtani, Badr; Karapinar, Erdal; Khojasteh, FarshidIn this paper, we propose a notion of a strong extended b-metric space and investigate the existence and uniqueness of a fixed point of certain operators.Article Citation - WoS: 6Citation - Scopus: 6Does Overparenting Hurt Working Turkish Mother's Well-Being? the Influence of Family-Work Conflict and Perceived Stress in Established Adulthood(Springer/plenum Publishers, 2023) Aydin, Eren Miski; Metin-Orta, Irem; Metin-Camgoz, Selin; Aksan, NazanAlthough extant research demonstrates the negative impact of overparenting on child well-being, there remains a paucity of evidence on the effect of overparenting on the parents' own well-being. The purpose of this study is to investigate the effects of overparenting on parental well-being, and to explore the mechanisms through which overparenting influences the well-being of working mothers, particularly among established adults. Thus, we examined the serial mediation effects of perceived stress and family-to-work conflict (FWC) in overparenting and well-being linkage. With this aim, the data were collected from working mothers (N = 258) aged between 30 and 45, a period of in their lifespan generally characterized by efforts devoted to career and care. Via serial mediation analyses, the findings postulate that (a) overparenting relates to the well-being and perceived stress of working mothers, (b) perceived stress (both individually and jointly with FWC) mediates the relationship between overparenting and well-being, and (c) perceived stress and FWC serially mediate the association between overparenting and well-being. The findings provide evidence related to the well-being experiences of established adulthood women in struggling their career-and care crunch from a perspective of overparenting, stress, and family-to-work conflict.Article Citation - Scopus: 1Production Fragmentation and Transport Mode Choice in Eu-28 Exports(Routledge, 2024) Türkcan,K.; Saygılı,H.This study uses detailed data on exports from the European Union (EU-28) to non-EU countries to investigate the impact of global production fragmentation on the choice of transportation modes. The article finds a positive relationship between production fragmentation and air transportation. The study also finds that air transportation is more likely to be chosen for high-value products. Additionally, the positive effect of production fragmentation on the likelihood of using air transportation is more pronounced when goods are exported to medium-range markets, upper-middle-income countries, countries with better air transportation infrastructure, and time-sensitive products. © 2024 Taylor & Francis Group, LLC.Article Citation - WoS: 2Citation - Scopus: 2Space-charge-limited currents and photoconductive properties of Tl2InGaSe4 layered crystals(Taylor & Francis Ltd, 2008) Qasrawi, A. F.; Gasanly, N. M.The extrinsic electronic parameters of Tl2InGaSe4 layered crystals were investigated through measurement of the temperature-dependent dark conductivity, space-charge-limited currents and photoconductivity. Analysis of the dark conductivity reveals the existence of two extrinsic energy levels at 0.40 and 0.51 eV below the conduction band edge, which are dominant above and below 260 K, respectively. Current-voltage characteristics show that the one at 0.51 eV is a trapping energy level with a concentration of (4.8-7.7) x 10(10) cm(3). Photoconductivity measurements reveal the existence of another energy level located at 0.16 eV. In the studied temperature range, the photocurrent increases with increasing temperature. The dependence of the photoconductivity on the incident light intensity exhibits a linear recombination character near room temperature and a supralinear character as the temperature decreases. The change in recombination mechanism is attributed to an exchange in the behavior of sensitizing and recombination centres.Article Citation - WoS: 24Citation - Scopus: 24Symplectic and multisymplectic Lobatto methods for the "good" Boussinesq equation(Amer inst Physics, 2008) Aydin, A.; Karasoezen, B.In this paper, we construct second order symplectic and multisymplectic integrators for the "good" Boussineq equation using the two-stage Lobatto IIIA-IIIB partitioned Runge-Kutta method, which yield an explicit scheme and is equivalent to the classical central difference approximation to the second order spatial derivative. Numerical dispersion properties and the stability of both integrators are investigated. Numerical results for different solitary wave solutions confirm the excellent long time behavior of symplectic and multisymplectic integrators by preservink local and global energy and momentum. (C) 2008 American Institute of Physics.
