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Article Citation - WoS: 45Citation - Scopus: 45An Ambipolar Low Band Gap Material Based on Bodipy and Edot(Elsevier Science Bv, 2009) Algi, Fatih; Cihaner, AtillaA novel donor-acceptor type conducting polymer based on BODIPY dye as acceptor and EDOT units as donor parts is synthesized electrochemically. The unique combination of BODIPY and EDOT units provides an ambipolar (n- and p-doping processes) low band gap material (4). This is the first example of p-n junction in an organic pi-conjugated material where BODIPY unit is incorporated directly in the main chain. Furthermore, the polymer film exhibits electrochromic behavior upon p-doping: a color change from light violet (neutral) to indigo (oxidized). (C) 2009 Elsevier B.V. All rights reserved.Article Citation - WoS: 1Citation - Scopus: 2Parametric Sensitivity Analysis and Performance Evaluation of High-Temperature Macro-Encapsulated Packed-Bed Latent Heat Storage System Operating With Transient Inlet Boundary Conditions(Mdpi, 2022) Mehrtash, Mehdi; Tari, IlkerThis paper presents the results of comprehensive numerical analyses in the performance of a packed-bed latent heat storage (PBLHS) system in terms of key performance indicators, namely charging time, charging rate, charging capacity, and charging efficiency. Numerical simulations are performed for the packed bed region using a transient two-dimensional axisymmetric model based on the local thermal non-equilibrium (LTNE) approach. The model considers the variation in the inlet temperature of the system as these storage systems are typically integrated with solar collectors that operate with intermittent solar radiation intensity. The model results are validated using the experimental data for temperature distribution throughout the bed. The simulations are carried out while changing the operating parameters such as the capsule diameter, bed porosity, inlet velocity, and the height-to-diameter aspect ratio to investigate their impact on the performance indicators. Observations indicate that low porosity, large-sized capsules, low inlet velocity, and a low height-to-diameter aspect ratio increase the charging time. In terms of achieving a high charging rate, a bed with low porosity, small-sized capsules, a high inflow velocity, and a high height-to-diameter aspect ratio is deemed advantageous. It is shown that raising the flow velocity and the height-to-diameter aspect ratio can improve the charging efficiency. These findings provide recommendations for optimizing the design and operating conditions of the system within the practical constraints.Article Citation - WoS: 3Citation - Scopus: 3Characterization of Mesenchymal Stem Cells in Mucolipidosis Type Ii (i-Cell Disease)(Tubitak Scientific & Technological Research Council Turkey, 2019) Köse, Sevil; Kaya, Fatima Aerts; Kuşkonmaz, Bülent Barış; Çetinkaya, Duygu UçkanMucolipidosis type II (ML-II, I-cell disease) is a fatal inherited lysosomal storage disease caused by a deficiency of theenzyme N-acetylglucosamine-1-phosphotransferase. A characteristic skeletal phenotype is one of the many clinical manifestationsof ML-II. Since the mechanisms underlying these skeletal defects in ML-II are not completely understood, we hypothesized that adefect in osteogenic differentiation of ML-II bone marrow mesenchymal stem cells (BM-MSCs) might be responsible for this skeletalphenotype. Here, we assessed and characterized the cellular phenotype of BM-MSCs from a ML-II patient before (BBMT) and afterBM transplantation (ABMT), and we compared the results with BM-MSCs from a carrier and a healthy donor. Morphologically, wedid not observe differences in ML-II BBMT and ABMT or carrier MSCs in terms of size or granularity. Osteogenic differentiation wasnot markedly affected by disease or carrier status. Adipogenic differentiation was increased in BBMT ML-II MSCs, but chondrogenicdifferentiation was decreased in both BBMT and ABMT ML-II MSCs. Immunophenotypically no significant differences were observedbetween the samples. Interestingly, the proliferative capacity of BBMT and ABMT ML-II MSCs was increased in comparison to MSCsfrom age-matched healthy donors. These data suggest that MSCs are not likely to cause the skeletal phenotype observed in ML-II, butthey may contribute to the pathogenesis of ML-II as a result of lysosomal storage-induced pathology.Article Citation - WoS: 17Citation - Scopus: 16The Approximation by q-bernstein Polynomials in the Case q ↓ 1(Springer Basel Ag, 2006) Ostrovska, SLet B-n (f, q; x), n = 1, 2, ... , 0 < q < infinity, be the q-Bernstein polynomials of a function f, B-n (f, 1; x) being the classical Bernstein polynomials. It is proved that, in general, {B-n (f, q(n); x)} with q(n) down arrow 1 is not an approximating sequence for f is an element of C[0, 1], in contrast to the standard case q(n) up arrow 1. At the same time, there exists a sequence 0 < delta(n) down arrow 0 such that the condition 1 <= q(n) <= delta(n) implies the approximation of f by {B-n(f, qn; x)} for all f is an element of C[0, 1].Conference Object Citation - WoS: 15Citation - Scopus: 15Refractive Index, Static Dielectric Constant, Energy Band Gap and Oscillator Parameters of Ga2ses Single Crystals(Wiley-v C H verlag Gmbh, 2007) Qasrawi, A. F.; Gasanly, N. M.The optical properties of Bridgman method grown Ga2SeS crystals have been investigated by means of room-temperature transmittance and reflectance spectral analysis. The optical data have revealed direct and indirect allowed transition band gaps of 2.49 and 2.10 eV, respectively. The room-temperature refractive index, which was calculated from the reflectance and transmittance data, allowed the identification of the dispersion and oscillator energies, static dielectric constant and static refractive index as 20.93 eV and 4.01 eV, 6.21 and 2.49, respectively.Article Citation - WoS: 30Citation - Scopus: 34Preparation and Testing of Nafion/Titanium Dioxide Nanocomposite Membrane Electrode Assembly by Ultrasonic Coating Technique(Wiley-blackwell, 2014) Devrim, Yilser; Alemdaroğlu Temel, Mine; Alemdaroğlu Temel, MineMembrane electrode assemblies with Nafion/nanosize titanium dioxide (TiO2) composite membranes were manufactured with a novel ultrasonic-spray technique (UST) and tested in proton exchange membrane fuel cell (PEMFC). The structures of the membranes were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis. The composite membranes gained good thermal resistance with insertion of TiO2. The SEM and XRD techniques have proved the uniform and homogeneous distribution of TiO2 and the consequent enhancement of crystalline character of these membranes. The existence of nanometer size TiO2 has improved the thermal resistance, water uptake, and proton conductivity of composite membranes. Gas diffusion electrodes were fabricated by UST. Catalyst loading was 0.4 (mg Pt) cm(-2) for both anode and cathode sides. The membranes were tested in a single cell with a 5 cm(2) active area operating at the temperature range of 70 degrees C to 110 degrees C and in humidified under 50% relative humidity (RH) conditions. Single PEMFC tests performed at different operating temperatures indicated that Nafion/TiO2 composite membrane is more stable and also performed better than Nafion membranes. The results show that Nafion/TiO2 is a promising membrane material for possible use in PEMFC at higher temperature. (c) 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40541.Article Citation - Scopus: 3The early Turkestani émigré struggle and turkestanism: Nation – imagining in emigration: 1925-1940;(Ahmet Yesevi University, 2016) Karasar,H.A.The early Turkestani émigré struggle was an important example of ‘nation imagining’ in emigration. In this article, the challenges faced by Turkestani nationalist leaders who had left their fatherland after the Bolshevik invasion of their country are examined. The activities of émigré leaders and pan-Turkists like Zeki Velidî Togan, Mustafa Çokayoğlu, Osman Hoca and Nihal Atsız are illustrated in some detail. Special attention is given to policy formation, propaganda tactics, the use of media (mainly by publishing periodicals), and the organization of NGOs with the mission of setting and uniting the public (in diaspora) against Russian invasion. It is hoped that this discussion will enable researchers to make better assessments of the past and intelligent projections for the future. The work is based on extensive original sources, most of which have not been exploited before in English language publications. © 2016, Ahmet Yesevi University. All rights reserved.Article Citation - WoS: 2Citation - Scopus: 2Investigations of Ph-Dependent Dynamic Properties of Ompg-16sl, an Outer Membrane Protein G Mutant by Atr-Ftir Spectroscopy(Elsevier, 2022) Yilmaz, Irem; Korkmaz, FilizIn this paper, the dynamic properties of outer membrane protein G mutant (OmpG-16SL) are investigated with ATR-FTIR spectroscopy. While OmpG-WT has 14 beta-strands in its structure, the mutant is designed to have 16 beta-strands with the intention of creating an enlarged pore. Loop L6 is elongated by introducing six residues, two of which are negatively charged. The solvent accessibility of the OmpG-16SL mutant is compared with WT and a previously reported mutant OmpG-16S by tracking the H-1/H-2 exchange kinetics in acidic and neutral buffer conditions. The exchange kinetics and dynamics in the fast and slow exchange phases are separately investigated using the 2DCOS technique, which enables the tracking of the structural changes at each phase of the exchange process. The results suggest that the mutant OmpG-16SL is equally exposed to buffer in both acidic and neutral pH conditions. Additionally, the time range in the fast phase is very short - one-tenth of that for WT - and most of the exchange is completed in this phase. This fast exchange within minutes is also indicative of the presence of highly flexible and/or unstructured regions. In all, the fast exchange rates independent of the buffer pH justify the assumption that there is an altered interaction among the charged residues, which leads to a steadily-open pore. The role of the side-chain interactions within the pore and between the loops involving the loop L6 is also discussed.Article Citation - WoS: 14Citation - Scopus: 18Traps distribution in sol-gel synthesized ZnO nanoparticles(Elsevier, 2019) Delice, S.; Isik, M.; Gasanly, N. M.The distribution of shallow traps within the sol-gel synthesized ZnO nanoparticles was investigated using thermoluminescence (TL) experiments in the 10-300 K temperature range. TL measurements presented two overlapped peaks around 110 and 155 K. The experimental technique based on radiating the nanoparticles at different temperatures (T-exc.) between 60 and 125 K was carried out to understand the trap distribution characteristics of peaks. It was observed that peak maximum temperature shifted to higher values and activation energy (E-t) increased as irradiating temperature was increased. The E-t vs. T-exc. presented that ZnO nanoparticles have quasi-continuously distributed traps possessing activation energies increasing from 80 to 171 meV. (C) 2019 Elsevier B.V. All rights reserved.Conference Object GC Contents of the Genes May Imply Associations with Coronary Artery Disease, Autism, Obesity, and Type 2 Diabetes(Wiley, 2025) Adiguzel, Y.; Yekeler, S. E.; Mohamed, A. A.; Turker, D.; Ozcan, L. E.; Sert, G.; Acet, K.
