Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395

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  • Article
    Use of Confocal Microscopy to Monitor Structural Transformations in Nanopillars Based on DNA and CdSe/CdZnSe Quantum Dots
    (Springer, 2023-06-24) Motevich, I. G.; Erdem, T.; Akrema, A.; Maskevich, S. A.; Strekal, N. D.
    Chip system prototypes in the form of nanopillars were created from DNA complexes with CdSe/CdZnSe/ZnS quantum dots immobilized on a plasmonic gold fi lm by the use of vacuum deposition technology and inorganic synthesis. The design and presence of terminal DNA labeled with Cy3 cyanine dyes makes it possible to carry out the hybridization reaction of this terminal strand with complementary DNA and to control the process by variation of the giant Raman scattering (GRS) and the fluorescence signal. The effect of molecular recognition of complementary DNA is accompanied by a change in the GRS spectrum, a 20-fold increase in the fluorescence intensity, and a decrease in the duration of fluorescence decay.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 10
    The Size and Concentration Effects of Al2O3 Nanoparticles on PSF Membranes With Enhanced Structural Stability and Filtration Performance
    (Desalination Publ, 2017-07) Saki, Seda; Uzal, Nigmet; Ates, Nuray
    Nanocomposite membranes have attracted attention for their high permeability, rejection efficiency, and thermal and mechanical stability. In this study, novel flat-sheet polysulfone nanocomposite membranes were prepared by a phase inversion method with polyethylenimine and Al2O3 nanoparticles to increase the flux and hydrophilicity. Al2O3 nanoparticles were added to the membrane matrix to enhance the permeability, selectivity, and mechanical resistance. Two different sizes of Al2O3 nanoparticles (20 and 80 nm) were used with different weight percentages of 0.2, 1, and 5 wt%. The effects of the size and concentration of the nanoparticles on the structural properties and filtration performance of the membranes were investigated. Scanning electron microscopy, Fourier transform infrared spectroscopy, porosity, water contact angle, thermogravimetric analysis, viscosity, and tensile strength measurements were used to characterize the prepared membranes. The membrane performance was evaluated with water flux and bovine serum albumin rejection tests. According to the results, the membrane containing 15 wt% polysulfone, 1 wt% polyethylenimine, and 5 wt% 20 nm Al2O3 showed the highest pure water flux, porosity, viscosity, and morphological stability. This membrane may have potential uses in water treatment applications.
  • Conference Object
    Citation - WoS: 5
    Citation - Scopus: 6
    The Selection of Washing Machine Programs With Fuzzy Dematel and Moora-Ratio Multi-Criteria Decision-Making Methods Considering Environmental and Cost Criteria
    (Elsevier Science inc, 2024-01) Fidan, Fatma Sener; Aydogan, Emel Kizilkaya; Uzal, Nigmet
    The washing machine is the prevalent white household equipment in contemporary society. These machines provide consumers with a range of program options that encompass several variables, including temperature and detergent type. Nevertheless, the selection made by individual customers about the washing machine program they opt for carries substantial environmental consequences during the use stage of textile products. According to studies on the life cycle of clothes, it has been established that the use stage, following the extraction of raw materials, exerts the most substantial influence on environmental impacts. The objective of this research is to assess the washing machine programs provided by the manufacturer through the application of a comprehensive systematic approach for analysis. The evaluation of scenarios for washing machine programs was conducted using the MOORA-Ratio multi-criteria decision-making process. This evaluation considered various parameters, including environmental impact and cost. The life cycle assessment methodology was employed to quantify the environmental impact of the specified criteria. Based on the comprehensive study conducted by integrating criteria across numerous dimensions, it has been determined that the most favorable scenario wass scenario 1, which was developed for the Cotton 20 C program. The primary objective of this research endeavor is to fill a significant need in the current body of literature by undertaking a comprehensive review of washing machine programs that have not been previously recorded. This study employs a comprehensive methodology to investigate the environmental and economic implications linked to these activities, with the objective of delivering significant insights to producers and users.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    The Nexus of Leadership, Political Empowerment, and Social Mobilization: The Case of the July 15 Coup Attempt in Turkey
    (Seta Foundation, 2020-06-30) Donmez, Rasim Ozgur; Timur, Kasim; Lloyd, Fatma Armagan Teke
    This study analyzes the mutually empowering relations between Turkish President Recep Tayyip Erdogan and his followers, and how Erdogan's charismatic leadership and image functioned to galvanize his followers on the night of July 15, 2016, when large numbers of them mobilized against the attempted coup. The article has three sections. The first is a theoretical discussion which sheds light on the concept and the underlying mechanisms of political empowerment and its effects on the relationships between leaders and followers. The second section evaluates Erdogan's characteristics and ruling style, which was instrumental in motivating resistance to the abortive coup. Finally, the third section analyzes the various means by which Erdogan was able to inspire the masses to mobilize against the armed junta through interviews and observations.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Structural Profile Matrices for Predicting Structural Properties of Proteins
    (World Scientific Publ Co Pte Ltd, 2020-07-10) Azginoglu, Nuh; Aydin, Zafer; Celik, Mete
    Predicting structural properties of proteins plays a key role in predicting the 3D structure of proteins. In this study, new structural profile matrices (SPM) are developed for protein secondary structure, solvent accessibility and torsion angle class predictions, which could be used as input to 3D prediction algorithms. The structural templates employed in computing SPMs are detected by eight alignment methods in LOMETS server, gap affine alignment method, ScanProsite, PfamScan, and HHblits. The contribution of each template is weighted by its similarity to target, which is assessed by several sequence alignment scores. For comparison, the SPMs are also computed using Homolpro, which uses BLAST for target template alignments and does not assign weights to templates. Incorporating the SPMs into DSPRED classifier, the prediction accuracy improves significantly as demonstrated by cross-validation experiments on two difficult benchmarks. The most accurate predictions are obtained using the SPMs derived by threading methods in LOMETS server. On the other hand, the computational cost of computing these SPMs was the highest.
  • Article
    Strand Wire Winding Method in a Solenoidal Coil With Limited Geometry for Good Impedance Matching
    (Polska Akademia Nauk, 2023-03-30) Kiliç, Veli Tayfun
    This paper reports a new strand wire winding method in a solenoidal coil with limited geometry that enables good impedance matching. In the proposed method strand wires are wound layer-by-layer on top of each other allowing one to set equivalent inductance and resistance of the coil to desired values while obtaining dense magnetic flux and high current carrying capacity. As a proof-of-concept demonstration, simple model setups were constructed with solenoidal coils composed of copper wire strands wound according to the proposed method, and a plastic pipe. The measurements were repeated with a metal shell placed inside the coil to model a complete heating system. System inductance and resistance were measured at two different frequencies. The results show that with the new winding method it is possible to increase a coil’s turn number and the number of strand layers composed by the coil. Also, adding and removing strand layers in the proposed coil architectures enable inductance and resistance values to decrease and increase, respectively, in a controlled way. To understand changes of system parameters, simulations were also performed. The calculated inductance and resistance values in the simulations agree well with the measurement results and magnetic flux distribution created in the system demonstrates the changes. © 2023 Elsevier B.V., All rights reserved.
  • Editorial
    Citation - WoS: 3
    Citation - Scopus: 3
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Simultaneous Low Noise Radio Frequency Tone and Narrow Linewidth Optical Comb Generation From a Regeneratively Mode-Locked Laser
    (SPIE - Society of Photo-Optical Instrumentation Engineers, 2014-10-29) Ozdur, Ibrahim; Ozharar, Sarper; Delfyett, Peter J.
    A regeneratively mode-locked laser with simultaneous low noise radio frequency (RF) tone and optical comb generation is presented. The laser does not need any external RF signal and emits a pulse train at similar to 10 GHz repetition rate with a 1.5-ps optical pulse width after compression. The generated RF tone has a signal-to-noise ratio of 121 dB/Hz and an RF fluctuation of 10(-9) over 0.1 s. The optical frequency comb spacing is also at similar to 10 GHz and the optical comb tooth has a linewidth of <1 kHz. (C) 2014 Society of Photo-Optical Instrumentation Engineers (SPIE)
  • Article
    Citation - WoS: 7
    Citation - Scopus: 9
    Robust Tracking Controller for SEPIC Drivers
    (Inst Engineering Technology-IET, 2016-11) Ablay, G.
    The non-minimum phase, non-linear nature of the SEPIC (single-ended primary inductor converter) makes it very difficult to get robust operating conditions under load variations. Sliding-mode control method is utilised to design a robust controller for tracking control of SEPIC converters for various applications. The implementation of the method is illustrated with the use pulse-width modulation comparators in the control loop to preclude the risk of modulator saturation and to ease the operations. The performance of the SEPIC converter is investigated through numerical simulation and analogue electronics implementation to show the validity, robustness and feasibility of the proposed controller.
  • Article
    Citation - WoS: 34
    Citation - Scopus: 41
    Revisiting the Relationship Between Natural Gas Consumption and Economic Growth in Turkey
    (Taylor & Francis inc, 2015-01-12) Dogan, E.
    The objective of this study is to re-analyze the relationship between natural gas consumption (NGC) and economic growth (GR) for Turkey in a multivariate framework by including capital and labor as additional variables because several papers suggest that a bivariate model can suffer from omitted-variables bias. As compared to the findings of Isik (2010), who previously investigated the short-and long-run relationships between GR and NGC using a bivariate model, we find that the magnitude of the coefficient estimate of NGC become substantially smaller in the long-run and the sign of short-run estimate of NGC shift to negative after accounting for capital and labor as well. In addition to that covered by Isik (2010), we investigate the direction of causality between GR and NGC using the vector error correction model Granger causality approach, and reveal the evidence of feedback hypothesis for Turkey.