Digital Commons Network^™

An Investigation Of Structural Properties And Surface Morphologies Ofelectrochemically Fabricated Nanocrystalline Ni-Co-Cu/Ito Deposits Withdifferent Compositions, Umut Saraç, Mevlana Celaletti̇n Baykul

Turkish Journal of Physics

In this study, nanocrystalline ternary Ni-Co-Cu/ITO deposits with different compositions were produced by using the electrochemical deposition technique from a sulfate-based bath solution with different Co ion concentrations. It was revealed that an increment in the Co ion concentration gives rise to an enhancement in the Co content but leads to a decrement in the Ni and Cu contents of the deposit structure. The Co-Cu and Ni-Cu exhibited normal codeposition behavior, while the Co-Ni showed anomalous codeposition behavior irrespective of the bath concentration. The change in the degree of the anomalous codeposition was also investigated according to the Co ion …

Analytical Solution Of D-Dimensional Radial Schrödinger Equation For Sexticpotential By The Extended Nikiforov-Uvarov Method And Biconfluent Heunpolynomials, Hasi̇be Hale Karayer

Turkish Journal of Physics

D-dimensional radial Schrödinger equation (SE) for sextic potential is solved using the extended Nikiforov-Uvarov method analytically. Energy eigenvalue and eigenfunction solutions are achieved systematically. It is also presented that the D-dimensional radial SE is transformed to biconfluent Heun equation (BHE). Therefore the eigenfunction solutions for the potential are attained in terms of biconfluent Heun polynomials when the condition of existence of polynomial solution of BHE is provided simultaneously.

Pseudoscalar Higgs Boson Pair Production At A Photon-Photon Collision In Thetwo Higgs Doublet Model, Mehmet Demi̇rci̇

Turkish Journal of Physics

In this study, the direct pair production of the pseudoscalar Higgs boson at a γγ collision is analyzed in the context of the two Higgs doublet model (THDM), taking into account the complete one-loop contributions. In order to illustrate the effect of the new physics, four benchmark point scenarios, which are consistent with theoretical and current experimental constraints, are chosen in the type-I THDM with an exact alignment limit. The effect of individual contributions from each type of one-loop diagram on the total cross-section is examined in detail. The dependence of the cross-section on the center-of-mass energy is also presented …

First Photometric Investigation Of Some Asas Binary Systems, Burak Ulaş

Turkish Journal of Physics

We present the first light curve solutions of the four binary systems observed and catalogued by the All Sky Automated Survey (ASAS) program. The light curves are analyzed by using PHOEBE software, which is based on the Wilson?Devinney method. The light curve parameters are derived and the estimated physical parameters are calculated from the result of the analyses. We compare our targets to well-known binaries of similar type on the Hertzsprung-Russell diagram and mass-radius plane. The evolutionary states of the components are also discussed.

Topography Of Electrospun Nanofibers And Its Influence On (Pot/Ps)/Si Hybridsolar Cell Parameters, Tariq Jaffar Alwan

Turkish Journal of Physics

Alignment nanofibers of poly(o-toluidine)/polystyrene (POT/PS) were prepared by using an electrospinning method at different applied voltages (Vappl.) of 10, 15, and 20 kV. The effect of the applied voltage on the morphology and electrical properties of POT/PS nanofibers was studied. Morphology and diameters of the nanofibers were investigated via atomic force microscopy. (POT/PS)/Si hybrid solar cells were fabricated through the deposition of POT/PS nanofibers on Si wafers using the electrospinning technique. The current-voltage measurements of the device under dark conditions exhibited asymmetrical and rectifying behavior for the Al/(POT/PS)/Si/Al junction, thereby confirming the formation of diodes. Diode parameters, such as ideality …

The Behaviour Of The Diamagnetic Current Modified Mri In Different Rotationprofiles, Suzan Doğan

Turkish Journal of Physics

Magnetohydrodynamic turbulence driven by magnetorotational instability (MRI) has been widely accepted as an efficient mechanism for transporting angular momentum radially outward in the discs. Previously, we have shown the triggering effect of the magnetization currents and the gradients produced by these currents on MRI for Keplerian discs. In this work, we examine the properties of the diamagnetic current modified MRI for the discs where the epicyclic frequencies deviate from Keplerian behaviour. We show that the diamagnetic effect modifies the instability both for an increasing and for a decreasing angular momentum with radius. The novel unstable region produced by magnetization effects …

Ab Initio Atomistic Thermodynamics Modeling Of Adsorption Of Oxygen On Goldand Gold-Silver Surfaces, Mehmet Gökhan Şensoy

Turkish Journal of Physics

A theoretical study of oxygen adsorption on gold and gold-silver surfaces by means of density functional theory (DFT) calculations with an atomistic thermodynamic model is performed. The (111) and (211) facets of gold and gold-silver alloy surfaces are considered, and their stabilization is discussed upon adsorption of oxygen depending on O and Ag coverage. The details of how the DFT-based atomistic thermodynamic model can apply to the transition metal surface are also presented in this work.

Two-Dimensional Ti2c Monolayer (Mxene): Surface Functionalization, Inducedmetal, Semiconductor Transition, Berna Akgenc

Turkish Journal of Physics

Recently, two-dimensional (2D) transition metal carbides and nitrides known as MXenes, have gained a lot of attention because of their tunable electronic and magnetic properties depending on surface functionalization. In the present work, the structural, electronic, and magnetic properties of both T and H phases of bare Ti2C and fully surface terminated Ti2 CT2 (T = -F, = O, -OH) are calculated using a set of first principles calculations. The ground state structures of Ti2 CT2 are computed in two and four different configurations for both H and T phases, respectively. We demonstrate that while H phase of Ti2C exhibits …

Quality Control Of Silicon Pixel Wafers For The Cms Phase-1 Pixel Upgrade, Kamuran Di̇lsi̇z, Süleyman Durgut, Kai Yi, Leonard Spiegel

Turkish Journal of Physics

The CMS detector at the CERN Large Hadron Collider features as its innermost component a silicon pixel detector. The original pixel detector was completely replaced during the 2016-2017 winter technical stop. One of the goals of this Phase-1 Upgrade of the pixel detector was to replace the sensors in the original CMS forward pixel detector with new, unirradiated sensors. The new CMS forward pixel detector must survive an integrated luminosity of 300 fb$^{-1}$ before being replaced again prior to the High-Luminosity LHC era. Just as in the original construction, the Phase-1 forward pixel sensors were made of n$^{+}$-in-n Diffusion Oxygenated …

A Hard X-Ray Self-Amplified Spontaneous Emission Free-Electron Laser Optimization Using Evolutionary Algorithms For Dedicated User Applications, Di̇dem Ketenoğlu, Gazi̇ Erkan Bostanci, Ayhan Aydin, Bora Ketenoğlu

Turkish Journal of Physics

Accelerator-based fourth-generation light sources are utilized in a wide range of interdisciplinary applications such as nanotechnology, materials science, biosciences, and medicine. A hard X-ray free-electron laser (FEL), as a state-of-the-art light source, was optimized using evolutionary algorithms for dedicated user applications such as X-ray Raman scattering (XRS), resonant inelastic X-ray scattering (RIXS), and X-ray emission spectroscopies (XES). Optimal parameter sets were obtained for an in-vacuum planar undulator driven by an 8 GeV electron beam. Performance parameters of self-amplified spontaneous emission (SASE) operation (i.e. optimized SASE performance parameters through evolutionary algorithms) were found to be consistent with operating X-ray FEL facilities …

Fabrication And Characterization Of Si-Pin Photodiodes, Emre Doğanci, Şenol Kaya, Ali̇ekber Aktağ, Eli̇f Sarigül Duman, Raşi̇t Turan, Huseyi̇n Karacali̇, Ercan Yilmaz

Turkish Journal of Physics

In this work, characteristics of silicon-based p$^{+\, }$type, intrinsic (I), n$^{-}$ type (Si-PIN) photodiodes with active area of 3.5 $\times $ 3.5 mm$^{2}$, 5.0 $\times $ 5.0 mm$^{2}$, or 7.0 $\times $ 7.0 mm$^{2}$ and their possible usage in optoelectronics were studied. The devices were fabricated in the Radiation Detector Application and Research Center (NÜRDAM) of Bolu Abant İzzet Baysal University, Turkey. To acquire the device specifications, the current-voltage (I-V) and the capacitance-voltage (C-V) measurements were carried out in the photoconductive mode. Quantum efficiency and spectral responsivity measurements were performed in the photovoltaic mode. Both measurements were carried out in …

Tuning The Electrical And Morphological Characteristics Of Pedot:Pss Films Through Mixed Cosolvent Addition And Performance Of Their Polymer Solar Cells, Çi̇sem Kirbiyik

Turkish Journal of Physics

This work aimed to reveal the influence of premixed cosolvent addition to low conductive PEDOT:PSS solution and how the optimized thin film conductivity develops. PEDOT:PSS thin films were obtained by addition of EG and MeOH cosolvent mixture (8, 10, and 15 v/v.%) and the morphological, electrical, optical, and bandgap properties of the films obtained were characterized by different techniques. The addition of mixed cosolvent can effectively control the grain size distribution and thus the conductivity. The optical characterization results revealed that the bandgap decreased with increasing volume of mixed cosolvent. The conductivity characteristics showed that the addition of 10% v/v.% …

Chemical Synthesis Of Zinc Oxide Nanorods And Their Transformation Intonanotubes, Pijus Kanti Samanta

Turkish Journal of Physics

A simple wet chemical method was successfully deployed to synthesize zinc oxide nanorods and nanotubes of hexagonal morphology. Energy dispersive X-ray spectroscopy confirmed the formation of ZnO with almost equal atomic percentages of Zn and O atoms. The FESEM images confirmed the formation of ZnO nanorods and nanotubes of length 1.5 to 2 $\mu $m and diameter 500 nm to 1 $\mu $m. The growth of the nanorods saturated under the combined effect of ionic association of Zn$^{2+}$ and OH$^{-}$ ions, Gibbs' energy of the reaction, reaction temperature, and the enthalpy of the system. Further stirring led to dissolution resulting …

On Possible Inversion Effects In The Technology Of Capillary-Porous Materials, Bulbul Yerzhenbek

Turkish Journal of Physics

The article discusses the possible place and role of the well-known thermodynamic Joule-Thomson effect in the technology of capillary-porous materials. The presence of the Joule-Thomson effect in these materials is substantiated by the peculiarities of the mechanism and kinetics of the diffusion physicochemical processes proceeding when they are heated. A mathematical description of the integral effects in capillary-porous materials under isothermal conditions is given.

Relativistic Dynamics Of A Scalar Boson Confined By Woods-Saxon Potential In Anucleus, Nuray Candemi̇r

Turkish Journal of Physics

We undertook a theoretical study of a scalar boson confined by Woods-Saxon potential in a nucleus via the Duffin-Kemmer-Petiau equation. We analytically obtained the eigenvectors and energy levels through the hypergeometric functions. Single-particle energy levels of a boson in the ${}^{208} {Pb}$ nucleus were calculated numerically.

A Hybrid Framework For Sentiment Analysis Using Genetic Algorithm Based Feature Reduction, Farkhund Iqbal, Jahanzeb Maqbool Hashmi, Benjamin C.M. Fung, Rabia Batool, Asad Masood Khattak, Saiqa Aleem, Patrick C.K. Hung

All Works

© 2019 IEEE. Due to the rapid development of Internet technologies and social media, sentiment analysis has become an important opinion mining technique. Recent research work has described the effectiveness of different sentiment classification techniques ranging from simple rule-based and lexicon-based approaches to more complex machine learning algorithms. While lexicon-based approaches have suffered from the lack of dictionaries and labeled data, machine learning approaches have fallen short in terms of accuracy. This paper proposes an integrated framework which bridges the gap between lexicon-based and machine learning approaches to achieve better accuracy and scalability. To solve the scalability issue that arises …

Study Of A = 100-150 Superdeformed Mass Region By Using Two-Parameterformula, Vidya Devi, Jagjit Singh Matharu

Turkish Journal of Physics

Empirical formulae of rotational spectra consisting two parameters, such as single-term energy formula, E = aJb for spin J , and ab formula, were used to study the different features of superdeformed band in A = 100-150 mass region nuclei. The nuclear kinematic and dynamic moment of inertia for the ground-state rotational bands were calculated for this purpose and both showed gradual rise with rotational frequency. The study of ΔI = 2 staggering effects in the γ-ray energies, where the two sequences J = 4i; 4i + 1 and J = 4i + 2, (i = 0; 1; ...) are …

Effects Of Cooling Rate On The Atomic Structure And Glass Formation Process Of Co90 Zr10 Metallic Glass Investigated By Molecular Dynamics Simulations, Murat Çeltek, Sedat Şengül

Turkish Journal of Physics

In this study, the atomic structure and the glass formation process of Co90 Zr10 metallic glass alloy were studied by molecular dynamic simulation based on the embedded atom method using four different cooling rates. The average atomic volume and the potential energy of the system were observed to be strongly dependent on the cooling rate during rapid solidification, and the glass transition temperature decreased with decreasing cooling rate. The radial distribution functions and the structure factors derived from molecular dynamics simulations at 300 K agreed well with the experimental and other molecular dynamics results. The coordination numbers calculated at 300 …

Effect Of Left-Handed Materials In Surface Plasmon Excitation And Propagationlength, Ari̇f Engi̇n Çeti̇n

Turkish Journal of Physics

We investigated the dispersion relation of surface plasmons (SPs) excited in a medium comprised of a left-handed material (LHM) layer. We investigated different light polarizations in SP excitation along an LHM-metal interface. We studied SP excitation through a classical Kretschmann geometry, employing an LHM interlayer between a dielectric and a metal layer. Using this three-layer configuration, we investigated the effect of LHM medium on characterizing SP propagation length, which is directly related to the energy of the surface waves.

Autonomous Piston Engine Guided By The Transduction Of Radiation Pressure Inoptomechanical Brownian Motors, Yusuf Gül

Turkish Journal of Physics

We consider the autonomous piston engine in a coupled cavity scheme in an optomechanical setup. Treating the radiation field as working fluid, we investigate the transduction of virtual photons due to ground state excitations. Rabi-like energy splittings and Casimir effect are shown by avoided crossing in the eigenfunction spectrum. Second order coherence functions are employed to analyze the bunching of the cavity and mechanical mode in optomechanical implementation of Brownian motors. The imbalance in occupation numbers of the working modes is investigated for the power for work extraction. We explore the guidance of the radiation field in work extraction. We …

Lorentz-Violating Effects In Single W Boson Production At The Lhc, Serdar Spor, İnanç Şahi̇n

Turkish Journal of Physics

We investigate the Lorentz-violating effects of Standard Model Extension (SME) in single W boson production process pp → pγp → p W- q' X at the Large Hadron Collider (LHC). We employ the Weizsacker-Williams approximation for photons emitted from one of the incoming proton beams and consider γq → W- q' as a subprocess in the proton-proton collision. The behavior of the differential cross-section for various orientations of the constant background fields is obtained by taking into account longitudinal and transverse polarization states of the final W bosons.

First- And Second-Law Thermodynamic Analyses Of A Combined Natural Gas Cyclepower Plant: Sankey And Grossman Diagrams, Mehmet Onur Karaağaç, Ahmet Kabul, Hasan Oğul

Turkish Journal of Physics

The natural gas combined cycle power plant is one of the best options for generating electricity due to its use of low carbon fuels, high efficiency, and operational flexibility. These plants consist of a combination of Brayton and Rankine cycles, and investigation of these cycles is performed in this paper. Here the parameters of pressure and temperature used in the calculations are taken from a combined cycle power plant. The net power output of the system at 25 °C ambient temperature and 101.325 kPa pressure was calculated as 45 and 12 MW for Brayton and Rankine cycles, respectively. In addition, …

Effect Of Al Doping On The Magnetic And Elastic Properties Of Fe65 Ni35 Invar Alloys, Asli Çakir

Turkish Journal of Physics

Invar alloys have great importance due to their low thermal expansion coefficient. The effect of Al doping on Fe65 Ni35 Invar alloy was investigated by temperature-dependent magnetization and elastic modulus measurements. First, 0.44 at% and 2.24 at% of Al were substituted for Ni. Then X-ray diffraction measurements, Rietveld refinements, and scanning electron microscopy studies were performed to understand the effect of Al-doping on the face-centered cubic structure. The elastic modulus of Fe65 Ni35 and the Al-doped samples were measured in the temperature range 300 ≤ T ≤ 870 K using impulse excitation. The temperature dependence of magnetization and elastic modulus …

Enhanced Efficiency Of Cds/P3ht Hybrid Solar Cells Via Interfacial Modification, Sali̇h Yilmaz, İsmai̇l Polat, Murat Tomaki̇n, Ahmet Ünverdi̇, Emi̇n Bacaksiz

Turkish Journal of Physics

The present paper examines the effects of surface modification of CdS with diverse dyes on fabricated CdSbased hybrid solar cells. The X-ray diffraction results showed that CdS thin films had a hexagonal phase with a preferred orientation along the (101) plane. Scanning electron microscopy indicated that the CdS specimen was composed of a granular structure while a P3HT layer was formed from tiny grains. Band gaps of the CdS thin films and the P3HT layer were 2.45 eV and 1.98 eV, respectively. The absorption spectra showed that different dye loading caused an increase in the absorbance of CdS thin films …

On Memory Effect In Modified Gravity Theories, Ercan Kiliçarslan

Turkish Journal of Physics

In this work, we discuss the gravitational memory effect in higher derivative and infinite derivative gravity theories and give the detailed relevant calculations whose results were given in our recent works. We show that the memory effect in higher derivative gravity takes the same form as in pure GR at large distances, whereas at small distances, the results are different. We also demonstrate that, in infinite derivative gravity, the memory is reduced via error function as compared to Einstein's gravity. For the lower bound on the mass scale of nonlocality, the memory essentially reproduces the usual GR result at distances …

The Prism Model: Increasing Graduate Teaching Assistants’ Self-Perceptions Of Pedagogical Content Knowledge, Catharine Mattox

Theses and Dissertations

While graduate teaching assistants teach the majority of introductory lab and discussion sections at colleges and universities across the United States, there is a lack of empirical evidence on how to adequately prepare graduate teaching assistants for faculty roles and responsibilities outside of research. The purpose of this mixed methods study was to address a gap in the literature by examining a professional development activity that encouraged pedagogical content knowledge (PCK) development in conjunction with experiential learning for biology graduate teaching assistants. Specifically, this study sought to understand how: (a) the Teaching Triangles professional development activity supported biology graduate teaching …

African-American Male Teachers: Examining The Insight, Encounters, And Best Teaching Practices, Brandon Morgan

Theses and Dissertations

The experiences students have in schools has a large effect not only on their career choices but also on the way they interact with other members of society in the future. Specifically, the K-12 education system has an objective of ensuring that all students are adequately prepared to become responsible and productive members of society. Unfortunately, research shows that African-American male students and teachers face comparatively high levels of societal challenges compared to their Caucasian counterparts. General demographic trends reveal a serious concern.

While the number of black students entering the education system is increasing, there is a reduction in …

Stakeholders’ Perceptions Of An Undergraduate Teacher Preparation Program In Special Education In Jamaica, Keitha Ava Marie Osborne

Theses and Dissertations

The problem addressed in this study was that stakeholders (i.e., graduates, cooperating teachers, principals, and heads of special education departments) of a teacher preparation program in special education at a teachers’ college in western Jamaica had not been asked their perceptions of the effectiveness of the undergraduate program that was started in 2011.

The purpose of the study was to determine stakeholders’ perceptions of the preparedness and effectiveness of graduates of a teacher preparation program in special education at a teachers’ college in western Jamaica. The stakeholders were the recent fulltime graduates of the program, cooperating teachers, principals, and heads …

Measuring Employee Job Satisfaction During Workplace Downsizing, Trina Sanders

Theses and Dissertations

This applied dissertation was designed to examine the effects of workplace downsizing on employee job satisfaction among men and women and employees of different age groups. Results from an employee survey conducted annually by the organizational site indicated that employees had high stress levels, low employee satisfaction and morale, negative attitudes, and a lack of trust of leadership following employee downsizing at the company. The purpose of this quantitative study was to examine the effects of workplace downsizing on employee job satisfaction to determine any differences by gender or age group.

The study utilized a quantitative, descriptive, comparative methodology using …

Acceptability And Usability Of E-Books For Digital Immigrant Teachers In A Title I Elementary School, Allatesha Denise Cain

Theses and Dissertations

The purpose of this study is to discover the factors that affect digital immigrant teachers’ acceptance and usability of e-books in a Title I elementary school. The term digital immigrant describes individuals born before the adoption of digital technology in 1980. The participant teachers will be interviewed to identify their perception of usefulness of the e-book to improve the reading skills of their students. Data from the interviews will be analyzed to identify the relationship between teachers’ perception of usefulness and ease of use of e-books and their intention to use e-books in a Title I elementary school.

This study …