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Articles 1 - 30 of 61
Full-Text Articles in Physical Sciences and Mathematics
Study Of The Energetic Field Characteristics Of The Te-Modalwaves In Waveguides, Fati̇h Erden
Study Of The Energetic Field Characteristics Of The Te-Modalwaves In Waveguides, Fati̇h Erden
Turkish Journal of Physics
The energetic characteristics of cylindrical medium-free time-domain waveguide fields are solved within the framework of the evolutionary approach to electromagnetics. Solving the boundary-eigenvalue problem for transverse Laplacian yields a configurational basis in the waveguide cross section. Elements of the basis depend on transverse coordinates, whereas the modal amplitudes depend on the longitudinal coordinate, $z,$ and time, $t$. Solving the resulted Klein-Gordon equation yields a basis for analysis of the modal amplitudes. Exact solutions for the amplitudes of TE-modes are obtained, and the energetic field characteristics are derived in accordance with the causality principle.
Determination Of Height Profile From A Two-Dimensional Fringe Signal Using A Two-Dimensional Continuous Wavelet Transform, Özlem Kocahan Yilmaz
Determination Of Height Profile From A Two-Dimensional Fringe Signal Using A Two-Dimensional Continuous Wavelet Transform, Özlem Kocahan Yilmaz
Turkish Journal of Physics
The main objective of this study was 3-dimensional (3D) profile measurements with standard fringe projection, consisting of a CCD and a projector. For obtaining height information of objects pixel by pixel, phases have to be calculated from the images taken by the fringe projection technique. In this study, the 2-dimensional continuous wavelet transform (2D CWT) phase method was used for phase extraction. 1D and 2D CWT analyses of noisy images were compared in simulations performed for a 2-dimensional fringe signal by introducing the carrier frequencies in two spatial directions, $x $ and $y$. Profile measurement of an object was made …
Influence Of Silicon Dioxide Medium On The Structural And Electrical Properties Of Nickel Zinc Ferrite, Jacob George, Abraham Kutticheril Eapen
Influence Of Silicon Dioxide Medium On The Structural And Electrical Properties Of Nickel Zinc Ferrite, Jacob George, Abraham Kutticheril Eapen
Turkish Journal of Physics
Nickel zinc ferrite [(Ni$_{0.65}$Zn$_{0.35}$Fe$_{2}$O$_{4}) _{x}$ / (SiO$_{2}) _{1-x}$ where, x = 1.0, 0.85, 0.65, 0.50, 0.35, and 0.15] is synthesized using the glyoxylate precursor method. The synthesis, characterization, and electrical study of nickel zinc ferrites/SiO$_{2}$ powder with low dielectric constant, very low conductivity, and loss tangent with low frequency dispersion, suitable for good insulators, is reported here. X-ray diffraction, TGA, and FT-IR studies are employed for identifying crystalline phases and structure. Crystallite size is calculated by the Scherrer formula and Williamson--Hall equation and found to fall in the range of 4.9--25 nm. TEM of the samples shows spherical particles of …
Monte Carlo Simulation Of A Medical Linear Accelerator For Filtered And Fff Systems, Çağri Yazğan, Yi̇ği̇t Çeçen
Monte Carlo Simulation Of A Medical Linear Accelerator For Filtered And Fff Systems, Çağri Yazğan, Yi̇ği̇t Çeçen
Turkish Journal of Physics
In order to simulate radiation transport, various algorithms, codes, and programs have been developed. In this study Monte Carlo N-particle code is used to simulate a medical electron linear accelerator gantry for research purposes. Detailed geometry of the LINAC head and water phantom are modeled and simulated for calculations. Analyses are made for filtered and flattening filter-free (FFF) systems. Percent depth dose and dose profile measurements are calculated with Monte Carlo simulations and compared with experimental and theoretical values for quality assurance of the model. Flux, dose, and spectrum analyses are performed for filtered and FFF systems separately. In this …
Applying A Self-Feedback Method To Control Chaos In The Buck Converter, Mei Mei Jia
Applying A Self-Feedback Method To Control Chaos In The Buck Converter, Mei Mei Jia
Turkish Journal of Physics
Chaos exists in the Buck converter due to the switching action of the controlled switch and this nonlinear phenomenon results in unreliable working performances. Hence, this paper uses a self-feedback control method with two adjustable parameters to suppress the chaotic behavior in the Buck converter. First, the self-feedback control method is presented by introducing a generic second-order chaotic system. Then, from the perspective of transfer functions obtained in terms of the piecewise linear model of the controlled Buck converter, effects of controller's parameters on system performances are discussed. On the basis of the Jacobian matrix of the discrete iterative mapping …
Spin (Pseudospin) Doublet In View Of Energy-Dependent Potential, Mustafa Salti, Oktay Aydoğdu
Spin (Pseudospin) Doublet In View Of Energy-Dependent Potential, Mustafa Salti, Oktay Aydoğdu
Turkish Journal of Physics
Behavior of Dirac particles in the presence of scalar, vector, and tensor potentials respectively represented by energy-dependent Morse and Coulomb-like potentials is examined by working out the Dirac equation under the condition of spin (pseudospin) symmetry. The closed form of the energy eigenvalue equation and corresponding wave functions in terms of hypergeometric functions are acquired by making use of the asymptotic iteration method. We investigate the effect of energy-dependent potential on both bound states and energy splitting between members of spin (pseudospin) doublets.
Higher-Dimensional Dust Collapse In F(R) Gravity, Zahid Ahmad, Muhammad Shoaib Khan
Higher-Dimensional Dust Collapse In F(R) Gravity, Zahid Ahmad, Muhammad Shoaib Khan
Turkish Journal of Physics
The $n+2$-dimensional gravitational collapse of pressureless fluid is investigated in metric $f(R)$ gravity. Matching conditions are derived by taking the $n+2$-dimensional Friedmann-Robertson-Walker (FRW) metric as interior spacetime and the $n+2$-dimensional Schwarzschild metric as exterior spacetime. In the analysis of the solution of field equations, the scalar curvature is assumed to be a constant. It is observed that the scalar curvature constant term $f(R_{0})$ slows the collapse.
Field-Free Molecular Alignment Control Of Filamentation, Necati̇ Kaya
Field-Free Molecular Alignment Control Of Filamentation, Necati̇ Kaya
Turkish Journal of Physics
With an approach of controlling the nonlinearity of medium rather than the light field, the effect of field-free molecular alignment on filamentation and resulting white-light generation is studied. This is done by measuring the rotational wavepacket evolution of nitrogen molecules after passing of a femtosecond laser pump pulse by observing the nonlinear propagation dynamics of a variably delayed filament-producing probe pulse.
Linear Instability Of Dust Acoustic Waves In A Magnetized Gravitating Plasma In The Presence Of Dust Streaming, Himangshu Sahoo, Basudev Ghosh, Kalyan Kumar Mondal
Linear Instability Of Dust Acoustic Waves In A Magnetized Gravitating Plasma In The Presence Of Dust Streaming, Himangshu Sahoo, Basudev Ghosh, Kalyan Kumar Mondal
Turkish Journal of Physics
Linear instability of dust acoustic waves (DAWs) has been theoretically studied in a collisionless gravitating dust-ion magnetized plasma including the effect of dust streaming. A linear dispersion relation has been derived by using the method of normal mode analysis. Gravitational effect is found to make the low-frequency DAW mode linearly unstable in certain parametric regions. The dependence of the growth rate of the instability on various plasma parameters such as streaming of dust particles, size of the dust grain, strength of the magnetic field, obliqueness of propagation, and number density of dust particles has been numerically analyzed and presented graphically.
Perturbative Construction Of The Two-Dimensional O(N) Nonlinear Sigma Model With Erg, Beki̇r Can Lütfüoğlu, Hidenori Sonoda
Perturbative Construction Of The Two-Dimensional O(N) Nonlinear Sigma Model With Erg, Beki̇r Can Lütfüoğlu, Hidenori Sonoda
Turkish Journal of Physics
We use the exact renormalization group (ERG) perturbatively to construct the Wilson action for the two-dimensional O(N) nonlinear sigma model (NLSM). The construction amounts to regularization of a nonlinear symmetry with a momentum cutoff. We find out that the model is parameterized by three functions. We show how to tune them by imposing the Ward--Takahashi (WT) identity. We construct two composite operators that generate infinitesimal change of the coupling constant and the renormalization of the scalar fields. Finally we show how the beta functions and the anomalous dimensions arise in the model up to 1-loop.
Effect Of Uv And Gamma Rays On Bulk Etching Of The Pokalon Track Detector, Madhusoodanan Pdmajam Gangadathan, Venkidasubramanian Sankar, Nishanth Pothiyodathu, Krishna Muraleedhara Varier
Effect Of Uv And Gamma Rays On Bulk Etching Of The Pokalon Track Detector, Madhusoodanan Pdmajam Gangadathan, Venkidasubramanian Sankar, Nishanth Pothiyodathu, Krishna Muraleedhara Varier
Turkish Journal of Physics
Solid-state nuclear track detectors (SSNTDs) find applications in many fields of science and technology. Polycarbonates like CR-39 or Lexan are most widely used for such applications. Pokalon is a relatively new member of the polycarbonate family of SSNTDs. It has the same monomer as that of Makrofol. In the present work we have studied the bulk etching characteristics of Pokalon at different temperatures and normalities of NaOH etchant with and without magnetic stirring. The effect of UV and gamma irradiation on the bulk etch rate has also been studied. From the bulk etch rate values at different temperatures, we have …
Marder Type Universe With Bulk Viscous String Cosmological Model In $F(R,T)$ Gravity, Sezgi̇n Aygün
Marder Type Universe With Bulk Viscous String Cosmological Model In $F(R,T)$ Gravity, Sezgi̇n Aygün
Turkish Journal of Physics
In this study, we have investigated homogeneous and anisotropic Marder space-time with bulk viscous string matter distribution in $f(R,T)$ gravity. For this aim we have used the anisotropy feature $(\frac{\sigma_{x}^{x} }{\theta })$ of Marder space-time and a deceleration parameter in two different $f(R,T)$ models. We have obtained bulk viscous matter distribution solutions in $f(R,T)$ gravity. Finally, some kinematical and physical properties are discussed.
Investigation Of Binary Co$_{2}$X (X = In, Si, Sb, Sn, Ga) Half-Heusler Alloys, Adewumi Isaac Popoola
Investigation Of Binary Co$_{2}$X (X = In, Si, Sb, Sn, Ga) Half-Heusler Alloys, Adewumi Isaac Popoola
Turkish Journal of Physics
The electronic structure and mechanical properties of some cobalt-based binary half-Heusler alloys Co$_{2}$X (X = In, Si, Sb, Sn, Ga) have been investigated using the density functional theory approach. The site preference by cobalt and X is similar to the traditional half-Heusler structure. The results showed that Co$_{2}$Si is not a half-metal but rather an n-type degenerate semiconductor. The compounds Co$_{2}$Ga, Co$_{2}$Sb, and Co$_{2}$Sn are thermodynamically unstable and Co$_{2}$In is elastically unstable. With much care given to the lattice size, half metallicity is readily predicted in Co$_{2}$In, Co$_{2}$Ga, Co$_{2}$Sn, and Co$_{2}$Sb. All the compounds showed directional bonding and they should …
Lightest And Heaviest Two-Neutron Halo Nuclei, $^{6}$He And $^{22}$C, Waleed Hwash
Lightest And Heaviest Two-Neutron Halo Nuclei, $^{6}$He And $^{22}$C, Waleed Hwash
Turkish Journal of Physics
The microscopic cluster model approach has been performed to study the nuclear structure of the lightest and heaviest two-neutron halo nuclei, $^{6}$He and $^{22}$C, respectively. The matter radius and binding energy for the $^{6}$He and $^{22}$C nuclei are calculated and the effect of the core deformation ($^{20}$C) on the properties of $^{22}$C nuclei is also discussed. Calculations have shown that the microscopic cluster model provides a good description of binding energy as well as matter radius in comparison to experimental data. The fittings of some parameters such as central potential depth (V$_{o})$, empirical constant (r$_{o})$, and surface diffuseness value (a) …
Bound-Free Pair Production With A Correction Term In Relativistic Heavy-Ion Collisions, Melek Yilmaz Şengül
Bound-Free Pair Production With A Correction Term In Relativistic Heavy-Ion Collisions, Melek Yilmaz Şengül
Turkish Journal of Physics
In our previous work, we calculated bound-free electron-positron pair production cross section without a correction term. In this work, bound-free electron-positron pair production with a correction term is considered to calculate the cross section for peripheral relativistic heavy ion collisions. The Dirac wave functions have been used for the leptons and first order corrections are included. It is seen that the results for the production cross sections are considerably smaller than those of the previous calculations. We applied the same method for the calculations of the antihydrogen production cross sections as well.
A Dft Study On The Electronic Structure Of Tungsten Trioxide Polymorphs, Masoud Mansouri, Tahereh Mahmoodi
A Dft Study On The Electronic Structure Of Tungsten Trioxide Polymorphs, Masoud Mansouri, Tahereh Mahmoodi
Turkish Journal of Physics
Tungsten trioxide ($WO_{3})$ is an intermediate product in the recovery of tungsten from its minerals. Recently, it has attracted increasing attention due to its exclusive structural properties and its high potential in electronic applications. The crystal lattice of tungsten trioxide is highly dependent on temperature. In this paper we investigated the equilibrium structure of tungsten trioxide in four crystal systems, i.e. monoclinic system, tetragonal system, orthorhombic system, and cubic system. We did our first principle calculations using a pseudopotential model based on the spin dependent density functional theory and implementing generalized gradient approximation for exchange correlation energy. In each case, …
Identification Of The Hadronic Interaction Layer In A Highly Granular Calorimeter By Multivariate Techniques, Burak Bi̇lki̇
Identification Of The Hadronic Interaction Layer In A Highly Granular Calorimeter By Multivariate Techniques, Burak Bi̇lki̇
Turkish Journal of Physics
Calorimetry in future and upgrade collider detectors has a clear overall trend towards high granularity, both laterally and longitudinally. This trend is a requirement for the full exploitation of particle flow algorithms, which reconstruct individual particles using the subdetector that provides the best resolution for this specific particle. The increased level of detail in the event topologies due to higher segmentation of the calorimeter provides additional handles for several calorimetric measurements, such as the identification of the hadronic interaction layer, which is not possible for calorimeters with traditional tower geometry. Here, the power of using multivariate statistical techniques in the …
Investigation Of Excitation Functions Of Proton-Induced Reactions On $^{94, 96, 98, 100}$Mo Targets For Production Of Radioisotopes $^{94m, 94g, 96m, 96g, 96, 99m}$Tc, Ozan Artun, Hüseyi̇n Ayteki̇n
Investigation Of Excitation Functions Of Proton-Induced Reactions On $^{94, 96, 98, 100}$Mo Targets For Production Of Radioisotopes $^{94m, 94g, 96m, 96g, 96, 99m}$Tc, Ozan Artun, Hüseyi̇n Ayteki̇n
Turkish Journal of Physics
In this work, we investigated the excitation functions of proton-induced reactions on even-even $^{94-100}$Mo isotopes for the production of medical radioisotopes $^{94m, 94g, 96m, 96g, 96, 99m}$Tc. To obtain the excitation functions we carried out cross-section calculations in the frameworks of the generalized superfluid model, microscopic level density model, and three options of the preequilibrium process in the Talys code. The aim of this study was to introduce a new aspect for the production of radioisotopes $^{94m, 94g, 96m, 96g, 96, 99m}$Tc with different models.
Enhanced Electro-Optic Modulation Of Linbo$_{3}$-Based Photonic Crystal Cavities With Dual Mode And Polarization Operation, Fulya Bağci, Gökhan Kurt, Bariş Akaoğlu, Ekmel Özbay
Enhanced Electro-Optic Modulation Of Linbo$_{3}$-Based Photonic Crystal Cavities With Dual Mode And Polarization Operation, Fulya Bağci, Gökhan Kurt, Bariş Akaoğlu, Ekmel Özbay
Turkish Journal of Physics
A high output transmission and high quality factor, compact LiNbO$_{3}$-based Fabry-Perot-type photonic crystal cavity is reported that can be used in electro-optical modulators at optical communication wavelengths. The electro-optic effect is 123 times enhanced as compared to the bulk material as a result of the slow light effect. The transmission wavelength is found to depend linearly on the applied voltage with 1.2 nm/V modulation sensitivity. Moreover, an externally switchable dual mode regime with high quality factors and transmissions is realized. High transmissions and high quality factors are also obtained for both transverse-electric and transverse-magnetic polarizations simultaneously.
Decomposition Of The Absorbed Dose By Let In Tissue-Equivalent Materials Within The Shield-Hit Transport Code, Nikolai Sobolevsky, Alexander Botvina, Ni̇hal Büyükçi̇zmeci̇, Ayşegül Kaya, Ludmila Latysheva, Riza Oğul
Decomposition Of The Absorbed Dose By Let In Tissue-Equivalent Materials Within The Shield-Hit Transport Code, Nikolai Sobolevsky, Alexander Botvina, Ni̇hal Büyükçi̇zmeci̇, Ayşegül Kaya, Ludmila Latysheva, Riza Oğul
Turkish Journal of Physics
The SHIELD-HIT transport code, in several versions, has been used for modeling the interaction of therapeutic beams of light nuclei with tissue-equivalent materials for a long time. All versions of the code include the useful option of decomposition of the absorbed dose by the linear energy transfer (LET), but this option has not been described and published to date. In this work the procedure of decomposition of the absorbed dose by LET is described and illustrated by using the decomposition of the Bragg curve in a water phantom, irradiated by beams of protons, alpha particles, and ions of lithium and …
Possible Variations In Sunspot Groups Before Flaring Activity During Solar Cycles 23 And 24, Ali̇ Kilçik, Seray Şahi̇n
Possible Variations In Sunspot Groups Before Flaring Activity During Solar Cycles 23 And 24, Ali̇ Kilçik, Seray Şahi̇n
Turkish Journal of Physics
We investigated the possible morphological variations observed in sunspot groups on the day before flaring activity occurred between January 1996 and November 2014. We found that 77% of all flaring sunspot groups were large and complex (D, E, and F modified Zurich classes). In addition, the Zurich classification of A, B, and C class sunspot groups changed more than 50%, while the remaining groups (D, E, F, and H) did not change considerably before the flare activity. Results showed that there was a remarkable increase in the sunspot areas of groups D, E, and F; in contrast, the sunspot areas …
Proton--Proton And Proton--Antiproton Differential Elastic Cross Sections Modeling At High And Ultra-High Energies Using A Hybrid Computing Paradigm, Elsayed Eldahshan
Proton--Proton And Proton--Antiproton Differential Elastic Cross Sections Modeling At High And Ultra-High Energies Using A Hybrid Computing Paradigm, Elsayed Eldahshan
Turkish Journal of Physics
This work presents a hybrid computing technique for modeling the differential elastic cross section of both proton--proton ``pp'' and proton--antiproton ``pp(bar)'' collisions from high to ultra-high energy regions (from 13.9 GeV to 14 TeV) as a function of the center-of-mass energy ``s'' squared and four momentum transfer squared ``t''. We proposed a genetic algorithm (GA) and support vector regression (SVR) hybrid techniques to calculate and predict the ``differential elastic cross section'' of both ``pp'' and ``pp(bar)''. Our proposed GA-SVR hybrid model shows a good match to the available experimental data, as well as predicting the latest and future ``TOTEM'' experiments …
Optical Visible Wavelength Region Selective Reflector Design For Photovoltaic Cells Using Photonic Crystal, Veysel Korkmaz, Ali̇ Çeti̇n
Optical Visible Wavelength Region Selective Reflector Design For Photovoltaic Cells Using Photonic Crystal, Veysel Korkmaz, Ali̇ Çeti̇n
Turkish Journal of Physics
In this study, we have proposed an optical broadband angular reflector having a band selective feature and high reflectivity rate for photovoltaic implementations by using a photonic crystal structure made of two different dielectric layers. This paper presents new and useful information about a reflector that was designed by using a periodic structure composed of two Si based layers for the visible range in the solar spectrum region. The system has been adjusted in such a way that it could cover a wide wavelength area between the photonic band gaps at nearly λ ≈ 300-800 nm. We have tested the …
The Effect Of Sintering In Different Atmospheres On Superconductivity Parameters Of Ybco, Mehmet Başoğlu
The Effect Of Sintering In Different Atmospheres On Superconductivity Parameters Of Ybco, Mehmet Başoğlu
Turkish Journal of Physics
YBa$_{2}$Cu$_{3}$O$_{7}$ (Y123) is a superconductor material discovered in 1987 and its transition temperature is above the liquid nitrogen temperature. It is known that superconductor samples produced by the solid-state reaction route are very often sintered in air atmosphere. However, in the presented work, Y123 was prepared by the same technique using a sintering ambient composed of a mixture of oxygen and argon gases for the first time. Critical current densities of the samples were calculated using results of magnetization measurements. It was obtained from magnetization analysis that all the samples exhibited superconductor character. It was also observed that the sample …
Effect Of Pu Content On Uncertainty In Reactor Parameters Due To Use Of No Temperature Gradient In (U-Pu)O$_{2}$ Fuels, Mehmet Türkmen
Effect Of Pu Content On Uncertainty In Reactor Parameters Due To Use Of No Temperature Gradient In (U-Pu)O$_{2}$ Fuels, Mehmet Türkmen
Turkish Journal of Physics
Radial temperature distribution in a fuel rod is a parabolic function. Neutronics calculations are in general performed over a volume-averaged temperature by ignoring this distribution. Such an assumption results in an uncertainty in reactor design parameters. In this study, the magnitude of this uncertainty is estimated by solving the heat equation with a temperature-dependent conductivity coefficient coupled with a reactor physics code. The effect of radial fuel temperature distribution is investigated by representing the fuel region as multiregional. Uncertainty is investigated for various Pu contents of (U-Pu)O$_{2}$ fuel, a mix of depleted U and reactor-grade Pu. The effect of Pu …
Comparison Of Structural Properties Of Some Liquid Crystals, Emi̇ne Mi̇ne Çapar
Comparison Of Structural Properties Of Some Liquid Crystals, Emi̇ne Mi̇ne Çapar
Turkish Journal of Physics
Molecular dynamics simulations were performed for three liquid crystalline molecules, 4-cyano-4$'$-octyloxybip- henyl (8OCB), n-p-cyanobenzylidene-p-octyloxyaniline (CBOOA), and p-n-hexyloxybenzylidene-p$'$-aminobenzonitrile (HBAB). Simulation data were obtained for three liquid crystals in the nematic and isotropic phases to analyze their structural properties. The imine spacer group in the Schiff bases induces a stepped core structure in which the linearity is maintained. The distributions of the angles between some defined vectors imply that the core segments of CBOOA and HBAB are more floppy than the 8OCB core. The biaxialities, molecular dimensions, and molecular anisotropies were calculated. The results were compared for three mesogens in the nematic …
Investigation Of Low-Lying Magnetic Dipole Excitations In The $^{153}$Eu Nucleus, Emre Tabar
Investigation Of Low-Lying Magnetic Dipole Excitations In The $^{153}$Eu Nucleus, Emre Tabar
Turkish Journal of Physics
The properties of low-lying magnetic dipole ($M$1) excitations in $^{153}$Eu were studied within a rotational invariant quasiparticle phonon model that takes into account the symmetry-restoring as well as spin-spin residual forces. The calculations show that there are purely collective $M$1 excitations lying at 2-4 MeV fragmented over orbital 1$^{+}$ states of the $^{152}$Sm core nucleus. The results were compared to the experimentally known $M$1 excitations at 2-3 MeV. A reasonably good agreement in the total transition strength, the centroid energy, and the resonance width was obtained.
Promising Features Of In$_{0.5}$Ga$_{0.5}$N/Al$_{0.2}$Ga$_{0.8}$N Quantum Dot Lasers, Halima Bouchenafa, Badra Bouabdallah, Boucif Benichou
Promising Features Of In$_{0.5}$Ga$_{0.5}$N/Al$_{0.2}$Ga$_{0.8}$N Quantum Dot Lasers, Halima Bouchenafa, Badra Bouabdallah, Boucif Benichou
Turkish Journal of Physics
The group-III nitrides, InN, GaN, and AlN, and their alloys have emerged as one of the most important material classes for optoelectronic devices. The incorporation of quantum dots (QDs) as active material improves the performance of conventional optoelectronic devices, such as laser diodes. In this study, we present a theoretical analysis of the gain characteristics of In$_{x}$Ga$_{1-x}$N/Al$_{0.2}$Ga$_{0.8}$N three-dimensional quantum box lasers, based on the density matrix theory of semiconductor lasers with relaxation broadening. The study is done on three samples of QDs: GaN/Al$_{0.2}$Ga$_{0.8}$N, In$_{0.3}$Ga$_{0.7}$N/Al$_{0.2}$Ga$_{0.8}$N, and In$_{0.5}$Ga$_{0.5}$N/Al$_{0.2}$Ga$_{0.8}$N. A comparative study of the gain spectra of GaN/Al$_{0.2}$Ga$_{0.8}$N-based quantum-well and QD lasers is …
Role Of Mg Doping In The Structural, Optical, And Electrical Characteristics Of Zno-Based Dsscs, İsmai̇l Polat, Sali̇h Yilmaz, Murat Tomaki̇n, Emi̇n Bacaksiz
Role Of Mg Doping In The Structural, Optical, And Electrical Characteristics Of Zno-Based Dsscs, İsmai̇l Polat, Sali̇h Yilmaz, Murat Tomaki̇n, Emi̇n Bacaksiz
Turkish Journal of Physics
ZnO- and Mg-doped ZnO samples are prepared by spray pyrolysis on conducting glass substrates to fabricate ZnO-based dye-sensitized solar cells (DSSCs). Influences of Mg-doping content on the power conversion efficiencies of ZnO-based DSSCs are investigated. X-ray diffraction results show that all the samples exhibit a hexagonal wurtzite structure. Scanning electron microscopy data indicate that the ZnO sample has uniform rods with 1 $\mu $m diameter. With respect to ZnO, the band gap value of 4 at.% Mg-doped ZnO samples improves to the value of 3.27 eV and a further increase in Mg level up to 6 at.% gives rise to …
Design Of Turkish Accelerator And Radiation Laboratory In Ankara (Tarla) Facility Injector Magnets, Avni̇ Aksoy
Design Of Turkish Accelerator And Radiation Laboratory In Ankara (Tarla) Facility Injector Magnets, Avni̇ Aksoy
Turkish Journal of Physics
The installation of a high current thermionic gun-based injector capable to accelerate a maximum 1.5 mA electron beam at 250 keV and continuous wave (CW) for various bunch repetition rates has been continuing at the Turkish Accelerator and Radiation Laboratory in Ankara (TARLA) since 2014. The injector, which is based on totally normal conducting technology, will mainly consist of a thermionic DC electron gun, two stage bunch compressor cavities operating at 260 MHz and 1.3 GHz, one dipole magnet, five solenoid lenses and an additional one dipole magnet that is going to be used as spectrometer, and several steerer magnets. …