Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- Electromagnetic transition (3)
- Multipolarity (3)
- Deformation parameters. (2)
- Molecular dynamics (2)
- Porous medium (2)
-
- 2D Gravity (1)
- Amorphous As_2Se_3 (1)
- And Fibonacci-class. (1)
- Assessment (1)
- Atomic fluorine. (1)
- BBM inequality (1)
- Band gap (1)
- Band structure (1)
- Black Holes in String Theory (1)
- Bulk modulus (1)
- CdS/CdTe; Solar cell; Tunnelling; Recombination. (1)
- CdS/Si heterojunction (1)
- Chalcogenide (1)
- Chalcogenide Glasses (1)
- Charge (1)
- Chemical bath Deposition (1)
- Cherenkov (1)
- Chiral (1)
- Coastal areas (1)
- Crystal (1)
- Debye temperature (1)
- Diffusion (1)
- Direct mechanism; Differential Cross-sections; Spectroscopic-factor amplitudes; Dependence of the integrated cross-sections on energy. (1)
- Dispersion (1)
- Duality. (1)
Articles 1 - 30 of 58
Full-Text Articles in Entire DC Network
48th Rocky Mountain Conference On Analytical Chemistry
48th Rocky Mountain Conference On Analytical Chemistry
Rocky Mountain Conference on Magnetic Resonance
Final program, abstracts, and information about the 48th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Breckenridge, Colorado, July 23-27, 2006.
Dwba Of The Reaction ^0be(P, \Alpha )^6li At E_P = 18.6\Sim 50 Mev, S. E. Abdel-Kariem
Dwba Of The Reaction ^0be(P, \Alpha )^6li At E_P = 18.6\Sim 50 Mev, S. E. Abdel-Kariem
Turkish Journal of Physics
The compound nucleus produced in the reaction ^9Be(p, \alpha)^6Li in the incident energy range E_p = 18.6 \sim 50 MeV is mainly occurred when its excitation energy is greater than the \alpha -particle threshold separation energy by about 20 MeV, strongly suggesting the reaction mechanism is a direct one-step process. To understand this phenomenon, we employ semi-microscopic zero-range distorted-wave Born approximation (DWBA) theory to analyse experimental data obtained in this energy range for the lower three ^6Li-states: ground state (1^+; 0); 2.186 MeV (3^+; 0); and 3.563 MeV (0^+; 1). The Kurath-Millener spectroscopic-factor amplitudes for the triton-cluster transfer are used …
Profiling Of Lithium And Potassium Into Silicon, Ali M. Mousa
Profiling Of Lithium And Potassium Into Silicon, Ali M. Mousa
Turkish Journal of Physics
The profiling of Lithium and Potassium into Silicon doped by electro deposition from molten salts (LiBr, KI) has been studied for various time periods and deposition currents. For the samples studied, changes in the deposition time and current have significant effects on the conductivity type and sheet resistance variation. This has been attributed to the high value of solid solubility of Lithium and Potassium in Silicon. Additionally, surface concentration variation with depth is affected significantly by variation in deposition time, particular for samples with a deposition time of 7 minutes. A junction was found 156 microns from the surface. For …
Optical Pulse Distortion In Fibonacci-Class Multilayer Stacks, A Rostami, S. Matloub
Optical Pulse Distortion In Fibonacci-Class Multilayer Stacks, A Rostami, S. Matloub
Turkish Journal of Physics
Optical pulse distortion and propagation through quasi-periodic structures generally and especially for Fibonacci-class, is investigated analytically and simulated numerically. In this analysis, the transfer matrix method (TMM) for distortion evaluation is used. The simulated results for Fibonacci-class quasi-periodic structures and pure periodic multilayer stacks are compared. We show that the Fibonacci-class quasi-periodic structure has a large dispersion coefficient with respect to a similar case in the periodic structure. So, quasi-periodic structures will destroy the incident pulse shape for smaller stack length than a periodic case in a similar situation. Finally, using output power, the distortion limit can be estimated and …
Inexpensive Near-Ir Photodetector, Omar A. Abdulrazaq, Evan T. Saleem
Inexpensive Near-Ir Photodetector, Omar A. Abdulrazaq, Evan T. Saleem
Turkish Journal of Physics
Fabrication and characterization of a CdS/Si heterojunction detector for 1.064 \mu m Nd:YAG laser detection has been carried out by pyrolytic spraying of CdS films onto single crystal n-type Si substrates. Response time has been determined in this study.
Tensor Polarization And Quadrupole Form Factor Of The Deuteron, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser
Tensor Polarization And Quadrupole Form Factor Of The Deuteron, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser
Turkish Journal of Physics
A new experimental value, M = 0.06925 \pm 0.00281, of the peak of the quadrupole form factor F_Q(q) is obtained by fitting the straight line relation found between the peak values of both T_{21}(q) and F_Q(q).
Transient Photoconductivity In Amorphous Se-Ge-Ag System, R. S. Sharma, D. Kumar, A. Kumar
Transient Photoconductivity In Amorphous Se-Ge-Ag System, R. S. Sharma, D. Kumar, A. Kumar
Turkish Journal of Physics
Transient Photoconductivity measurements have been made in vacuum evaporated thin films of Se_{0.80 - x}Ge_{0.20}Ag_x at different intensities, temperatures and illumination times. The films exhibit long-lived residual photoconductivity, called persistent photoconductivity, with an extremely slow decay rate. The persistent photoconductivity (PPC) increases with an increase in intensity and illumination time. However, this quantity decreases with increase in temperature. These results indicate that the decay of photoconductivity is not only governed by the carrier trapped in the intrinsic defects but also gets affected by the light induced defect creation through structural changes The persistent photoconductivity effect is found to be suppressed …
Stagnation Point Flow And Heat Transfer Of A Micropolar Fluid In A Porous Medium, Hazem Ali Attia
Stagnation Point Flow And Heat Transfer Of A Micropolar Fluid In A Porous Medium, Hazem Ali Attia
Turkish Journal of Physics
The steady laminar flow in a porous medium of an incompressible non-Newtonian micropolar fluid impinging on a permeable flat plate with heat transfer is investigated. A numerical solution for the governing nonlinear momentum and energy equations is obtained. The effect of the porosity of the medium and the characteristics of the non-Newtonian fluid on both the flow and heat transfer is presented and discussed.
A Treatment Of A Higher-Order Singular Lagrangian As Fields System, N. I. Farahat, M. R. Heles
A Treatment Of A Higher-Order Singular Lagrangian As Fields System, N. I. Farahat, M. R. Heles
Turkish Journal of Physics
The higher-order singular Lagrangian system is treated as field system. Euler-Lagrange equations are solved with some constraints. An example is studied and a comparison with Hamiltonian formulation is done.
The Investigation Of Screening Of Chromoelectric And Chromomagnetic Fields In Noncovariant Gauges, Elşen Veli̇, Jale Yilmazkaya Süngü
The Investigation Of Screening Of Chromoelectric And Chromomagnetic Fields In Noncovariant Gauges, Elşen Veli̇, Jale Yilmazkaya Süngü
Turkish Journal of Physics
According to Thermal Quantum Chromodynamics (TQCD) hadron matter may exist in the form of quark-gluon plasma (QGP) at high temperatures and densities. The aim of the present work is to investigate the screening of chromoelectric and chromomagnetic fields in QGP in noncovariant gauges. In noncovariant gauges, gluon propagator has unphysical poles and singularities appear in the gluon self-energy diagram calculations. In this paper, we investigate gluon self-energy in lightcone and temporal gauges. In order to remove singularities, we use the Mandelstam-Leibbrandt prescription (ML prescription). We obtain that chromoelectric fields are screened, but chromomagnetic fields are not screened. In coordinate space, …
Investigation Of The Multipolarity Of Electromagnetic Transitions In ^{88,90}Kr Nuclei, Nuretti̇n Türkan, Davut Olgun, İhsan Uluer, Sai̇t İnan
Investigation Of The Multipolarity Of Electromagnetic Transitions In ^{88,90}Kr Nuclei, Nuretti̇n Türkan, Davut Olgun, İhsan Uluer, Sai̇t İnan
Turkish Journal of Physics
We have determined the most appropriate Hamiltonian that is needed for present calculations of nuclei about the A \cong 80 region by the view of Interacting Boson Model-2 (IBM-2). After obtaining the best Hamiltonian parameters, level energies and B(E2) probabilities of some transitions in ^{88,90}Kr nuclei were estimated. Results are compared with previous experimental and theoretical data and it is observed that they are in good agreement. Finally, R_1 = \frac{B(E2;4_1 \to 2_1)}{B(E2;2_1 \to 0_1)}, R_2 = \frac{B(E2;2_2 \to 2_1)}{B(E2;2_1 \to 0_1)}, \ R_3 = \frac{B(E2;0_2 \to 2_1)}{B(E2;2_1 \to 0_1)}, R_4 = \frac{{B(E2;2_2 \to 0_1)}{B(E2;2_2 \to 2_1)}, R_5 = \frac{B(E2;3_1 …
Peculiarities Of The Electric And Thermoelectric Properties Of Gate, M. M. Nassary
Peculiarities Of The Electric And Thermoelectric Properties Of Gate, M. M. Nassary
Turkish Journal of Physics
Measurements of electrical conductivity, Hall coefficient and thermoelectric power were carried out over the temperature range 136--563 K for GaTe compound grown in single crystal form by modified Bridgman technique. The crystals obtained had Positive-type conductivity with a hole concentration of 3.8 \times 10^{12} cm^{-3} at room temperature. Conductivity and Hall mobility at room temperature were evaluated as 4.4 \times 10^{-3} ohm^{-1} cm^{-1} and 7079 cm^2/V \cdot s, respectively. The energy gap width of 1.5 eV was found. The effective mass of holes and electrons at room temperature were 4.16 m_° and 0.1174 m_° , respectively
Rotating Disk Flow With Heat Transfer Of A Non Newtonian Fluid In Porous Medium, Hazem Ali Attia
Rotating Disk Flow With Heat Transfer Of A Non Newtonian Fluid In Porous Medium, Hazem Ali Attia
Turkish Journal of Physics
The steady flow of an incompressible viscous non-Newtonian fluid above an infinite rotating disk in a porous medium is studied with heat transfer. Numerical solutions of the nonlinear differential equations which govern the hydrodynamics and energy transfer are obtained. The effect of the porosity of the medium and the characteristics of the non-Newtonian fluid on the velocity and temperature distributions is considered.
Tunneling-Enhanced Recombination In Polycrystalline Cds/Cdte Solar Cells, Habi̇be Bayhan
Tunneling-Enhanced Recombination In Polycrystalline Cds/Cdte Solar Cells, Habi̇be Bayhan
Turkish Journal of Physics
The dominant dark current transport mechanism in as-grown and CdCl_2 processed CdS/CdTe heterojunction solar cells for temperatures below 300~K was investigated. The current-voltage properties of these solar cells is explained via tunnelling enhanced bulk and interface recombination models which give a quantitative description of the electronic loss mechanisms in the chalcopyrite-based heterojunction solar cells. The temperature dependence of the saturation current and the diode ideality factors of the as-grown and CdCl_2 processed CdTe solar cells are shown to be well described by this model.
Cherenkov Radiation In Homogeneous Isotropic Chiral Media, Pierre Hillion
Cherenkov Radiation In Homogeneous Isotropic Chiral Media, Pierre Hillion
Turkish Journal of Physics
We present a Fourier transform analysis of Cherenkov radiation for a point charge uniformly moving inside a 2D-homogeneous, isotropic, unbounded, chiral medium endowed with the Drude-Born-Fedorov constitutive relations when the chirality parameter ß and the wave number k make negligible the ß^2k^2 terms. The electromagnetic field is not described in terms of circularly right and left polarized waves but in terms of TM and TE components. The Cherenkov radiation arises when the velocity v of the point charge is greater than the phase velocity c/n, where n is the refractive index of the chiral medium and the electromagnetic field stands …
Assessment Of Wind Power Potential For Coastal Areas Of Pakistan, M. Akhlaque Ahmed, Firoz Ahmed, M. Wasim Akhtar
Assessment Of Wind Power Potential For Coastal Areas Of Pakistan, M. Akhlaque Ahmed, Firoz Ahmed, M. Wasim Akhtar
Turkish Journal of Physics
Selected coastal areas of Pakistan (Karachi, Ormara, Jivani and Pasni) were studied for the possibility of wind energy generation, using available meteorological data. Wind speed pattern, Extractable Wind power, Wind Energy and associated Weibull parameter for these coastal areas have been examined. The analysis also includes seasonal changes in wind speed values. The power output using fast and slow wind machines using different blade diameters have been estimated to explore the possible use for irrigation deep well pumping and small scale power generation. Along with this, 4 KW and 20 KW aero generators were also examined. It was found that, …
Ensemble Teleportation, Thomas Krüger
Ensemble Teleportation, Thomas Krüger
Turkish Journal of Physics
The possibility of teleportation is by sure the most interesting consequence of quantum non-separability. So far, however, teleportation schemes have been formulated by use of state vectors and considering individual entities only. In the present article the feasibility of teleportation is examined on the basis of the rigorous ensemble interpretation of quantum mechanics (not to be confused with a mere treatment of noisy EPR pairs) leading to results which are unexpected from the usual point of view.
Pendant ^{13}C Nmr Spectroscopy Applied To Ch_N Groups, Azmi̇ Gençten, İrfan Şaka, Sedat Gümüş
Pendant ^{13}C Nmr Spectroscopy Applied To Ch_N Groups, Azmi̇ Gençten, İrfan Şaka, Sedat Gümüş
Turkish Journal of Physics
Polarization enhancement nurtured during attached nucleus testing (PENDANT) NMR spectroscopy gives signals of quaternary carbon atoms in addition to signals indicative of CH, CH_2 and CH_3 groups. In this study, using product operator theory, analytical description of PENDANT NMR spectroscopy for CH_n (IS_n, I = 1/2, S = 1/2, n = 0, 1, 2, 3) spin systems are presented. Simulation and experimental results of PENDANT NMR spectroscopy are also presented. Theoretical results are found to be in exact agreement with the simulation results and in good agreement with the experimental ones.
Effect Of Thermal Annealing On The Band Gap And Optical Properties Of Chemical Bath Deposited Znse Thin Films, F. I. Ezema, A. B. C. Ekwealor, R. U. Osuji
Effect Of Thermal Annealing On The Band Gap And Optical Properties Of Chemical Bath Deposited Znse Thin Films, F. I. Ezema, A. B. C. Ekwealor, R. U. Osuji
Turkish Journal of Physics
Zinc selenide (ZnSe) thin films were deposited on glass substrate using the chemical bath deposition method at room temperature from aqueous solutions of zinc sulphate and sodium selenosulfate in which sodium hydroxide was employed as complexing agents. The `as-deposited' ZnSe thin films are red in color and annealed in oven at 473 K for 1 hour and on a hot plate in open air at 333 K for 5 minutes, affecting the morphological and optical properties. Optical properties such as absorption coefficient \alpha and extinction coefficient k, were determined using the absorbance and transmission measurement from Unico UV-2102 PC spectrophotometer, …
The Calculations Of Oscillator Strengths And Transition Probabilities For Atomic Fluorine, Gülteki̇n Çeli̇k, H. Şükür Kiliç, Erhan Akin
The Calculations Of Oscillator Strengths And Transition Probabilities For Atomic Fluorine, Gülteki̇n Çeli̇k, H. Şükür Kiliç, Erhan Akin
Turkish Journal of Physics
Oscillator strengths for transitions between individual lines belonging to some doublet and quartet terms, and multiplet transition probabilities of atomic fluorine have been calculated using weakest bound electron potential model theory (WBEPMT). In the determination of relevant parameters, we employed numerical non-relativistic Hartree-Fock (NRHF) wave functions for expectation values of radii and the necessary energy values have been taken from experimental energy data in the literature. Oscillator strengths and transition probabilities obtained in this work have been compared to experimental and theoretical values given in the literature.
Phase Distribution Of The Output Of Jaynes-Cummings Model With The Superposition Of Squeezed Displaced Fock States, Gamal Mohamed Abd Al-Kader
Phase Distribution Of The Output Of Jaynes-Cummings Model With The Superposition Of Squeezed Displaced Fock States, Gamal Mohamed Abd Al-Kader
Turkish Journal of Physics
The Wigner quasi-probability function for the superposition of squeezed displaced Fock states (SDFS's) is reviewed. The interaction of these states with a two-level atom in cavity with the presence of additional Kerr medium is studied. Exact general matrix elements of the time-dependent operators of a Jaynes-Cummings model (JCM), in the presence of a Kerr medium, with these states are derived. We have obtained the phase distribution by two different ways: one is by Pegg-Barnett formalism, the second is by integration of the Wigner function over the radial variable. Results of these two approaches are compared. The Wigner phase distributions for …
Modulated Photoconductivity Studies Of A-As_2se_3 Thin Films, Ruhi̇ Kaplan
Modulated Photoconductivity Studies Of A-As_2se_3 Thin Films, Ruhi̇ Kaplan
Turkish Journal of Physics
Modulated photocurrent measurements in amorphous arsenic triselenide (a-As_2Se_3) is reported. Particular focus is paid towards photocarrier lifetimes as a function of temperature, and applied electric field (i.e. dc) were determined by using the quadrature frequency-resolved spectroscopy method. The activation energy from the photocurrent as a function of temperature was determined to be about 125 meV for a constant illumination intensity of 2.3 mW. Its value was found to be almost independent of the applied electric field. The exponent \nu in the power law relationship (I_{ph} \propto G^v) between generating flux and photocurrent was obtained under different electric fields. The electric …
Electrical Switching Behaviour In Lead Phosphovanadate Glasses, B. Sujatha, C. Narayana Reddy
Electrical Switching Behaviour In Lead Phosphovanadate Glasses, B. Sujatha, C. Narayana Reddy
Turkish Journal of Physics
Electrical switching behaviour of lead phosphovanadate glasses were studied by determining the current-voltage characteristics. All the investigated glasses exhibit the dependence of threshold voltages on temperature, thickness and composition. Below holding current the I - V characteristics obey Ohms law followed by a negative resistance region where the bulk behaviour dominates and at higher values of current the samples goes to a low resistance state. The studied glasses exhibit memory type switching. It is suggested that the initial switching and channel formation are due to electronic, while thermal effects dominate in the formation of channels.
Dimensional Crossover In Semiconductor Structures: From 3d Electron Transport To Ballistic Electrons In 1d, Karl-Fredrick Berggren
Dimensional Crossover In Semiconductor Structures: From 3d Electron Transport To Ballistic Electrons In 1d, Karl-Fredrick Berggren
Turkish Journal of Physics
Modern semiconductor technologies have made possible special devices in which a gradual dimensional crossover may be induced by means of applied electric fields. Two specific examples are described. The first one is a special GaAs field effect transistor in which the thickness of the active electron gas layer may be varied by external voltages. With decreasing layer thickness transverse states become quantized and by depopulating the corresponding subbands a tunable dimensional crossover from 3D to 2D is achieved. The second example describes how a 2D to 1D crossover may be obtained in high-mobility split-gate GaAs/AlGaAs heterostructures. Effects of interactions in …
Self-Assembled Nano-Structures On The Icosahedral Al-Pd-Mn Quasicrystal, Mehmet Erbudak, Jean-Nicolas Longchamp, Yves Weisskopf
Self-Assembled Nano-Structures On The Icosahedral Al-Pd-Mn Quasicrystal, Mehmet Erbudak, Jean-Nicolas Longchamp, Yves Weisskopf
Turkish Journal of Physics
A quasicrystal is a solid with an aperiodic atomic distribution, but displaying discrete diffraction pattern. At an interface where an ordinary crystal and a quasicrystal intersect, the lack of commensurability between the structures leads to misfits on atomic scale resulting in a wealth of novelties. Here, we present experimental observations on three essentially different cases: Al, Fe, and Si ultra-thin layers grown in vacuum on the pentagonal surface of an icosahedral Al-Pd-Mn quasicrystal. In all three cases, the growing layer decays into nm-size islands. Al is the major alloy component of the substrate material and provides a natural tool to …
Computational Studies On Mechanical Properties Of Carbon Nanotori, Tahi̇r Çağin, Guanghua Gao, William A. Goddard Iii
Computational Studies On Mechanical Properties Of Carbon Nanotori, Tahi̇r Çağin, Guanghua Gao, William A. Goddard Iii
Turkish Journal of Physics
Carbon has diverse structures, especially (0-dimensional) fullerenes, (1-dimensional) tubes have generated great interest among scientists and technologists. Studies of the structures and properties of these low dimensional carbon molecules show tremendous potential for use in nanoscale device applications. Motivated by these exciting possibilities in finding new forms of carbon materials and their potential applications, we have designed hypothetical single wall carbon nano-toroids. Carbon toroids are also ideal in studying the elastic and plastic deformation behavior of nanotubes under bending loads. We can accurately correlate the behavior of the tubes to its uniform curvature. In this particular work we focused on …
Relativistic Density Functional Theory Method: Applications To Autoionization States Of Atoms, Şaki̇r Erkoç
Relativistic Density Functional Theory Method: Applications To Autoionization States Of Atoms, Şaki̇r Erkoç
Turkish Journal of Physics
A brief introductory information about the accurate atomic calculations using Density Functional Theory has been reviewed. How relativistic effects can be considered in atomic calculations through the density functional theory has been discussed. Some sample calculation results for the autoionization states of the neutral and cationic atoms have been presented.
Tkachenko Modes Of The Square Vortex Lattice In A Two-Component Bose-Einstein Condensate, M. Keçeli̇, M. Ö. Oktel
Tkachenko Modes Of The Square Vortex Lattice In A Two-Component Bose-Einstein Condensate, M. Keçeli̇, M. Ö. Oktel
Turkish Journal of Physics
We study Tkachenko modes of the square vortex lattice of a two-component Bose-Einstein condensate (BEC) in the mean-field quantum Hall regime, considering the coupling of these modes with density excitations. We derive the hydrodynamic equations and obtain the dispersion relations of the excitation modes. We find that there are two types of excitations, gapped inertial modes and gapless Tkachenko modes. These modes have two branches which we call acoustic and optical modes in analogy with phonons. The former has quadratic while the latter has linear wave-number dependence in both inertial and Tkachenko modes. Acoustic Tkachenko mode is found to be …
Applications Of Genetic Algorithm To Quantum Mechanical Systems, Mehmet Şahi̇n, Ülfet Atav, Mehmet Tomak
Applications Of Genetic Algorithm To Quantum Mechanical Systems, Mehmet Şahi̇n, Ülfet Atav, Mehmet Tomak
Turkish Journal of Physics
Genetic algorithm (GA) inspired by the biological world is a general search and optimization method. It was first proposed by Holland in 1975. GA has been applied to many scientific areas especially in engineering optimization problems. It is also used in solving of quantum mechanical problems. In this study, we have applied this method to different realistic quantum mechanical problems of both self-consistent and non-self-consistent type. The results obtained are compared with the results of other methods and it is seen that the GA can be a very powerful alternative to some other traditional techniques such as variational method.
First Principles Approach To Batio_3, Mustafa Uludoğan, Tahi̇r Çağin
First Principles Approach To Batio_3, Mustafa Uludoğan, Tahi̇r Çağin
Turkish Journal of Physics
We present state of art first-principles study on the static and dynamic properties of BaTiO_3, a typical ferroelectric material. Here, structure, equation of state, phase stability, and phase transformations of BaTiO_3 studied in Generalized Gradient Approximation. Furthermore, properties such as, Born effective charges, optical dielectric constant and phonon spectra are calculated from Density Functional Perturbation Theory.