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- Diurnal (3)
- Activation energy (2)
- Cosmic ray (2)
- Semi-diurnal (2)
- AMPS-1D (1)
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- And anisotropy (1)
- Anharmonic oscillator (1)
- Anisotropy and Solar poloidal magnetic field. (1)
- Antireflective coating (1)
- Atomic properties (1)
- Auger vacancy cascades (1)
- B-decays (1)
- Bohm-Pines Transformation (1)
- Brick-wall method (1)
- Cation distribution (1)
- CdInGaS_4 (1)
- CdTe; Electrical properties; Hall effect; H_2T-VPE; X-ray detectors. (1)
- Chalcogenide glasses (1)
- Chemical potential (1)
- Chemical vapor deposition (1)
- Chlorophosphate glasses (1)
- Closure (1)
- Co-Zn-Mn ferrite (1)
- Correlated barrier hopping (1)
- Cosmic rays (1)
- Crystallization Kinetics. (1)
- Deformation parameter (1)
- Differential Scanning Calorimetry (1)
- Double-well potentials (1)
- E-beam; surface roughness; PMMA; phase separation; develop time. (1)
Articles 1 - 30 of 46
Full-Text Articles in Physical Sciences and Mathematics
Variation Of Chemical Potential Oscillations Of A 2deg In A Quantum Well Under A Magnetic Field For Multiple Sub-Band Occupation As Function Of Temperature And Level-Broadening, Berri̇n Özdemi̇r, Zeki̇ Yarar, Meti̇n Özdemi̇r
Variation Of Chemical Potential Oscillations Of A 2deg In A Quantum Well Under A Magnetic Field For Multiple Sub-Band Occupation As Function Of Temperature And Level-Broadening, Berri̇n Özdemi̇r, Zeki̇ Yarar, Meti̇n Özdemi̇r
Turkish Journal of Physics
We study the variation of chemical potential in a two dimensional electron gas in a uniform magnetic field as a function of temperature and level-broadening parameter. Schrödinger and Poisson equations are solved self-consistently for a two dimensional electron gas formed in a Ga_xAl_{1-x}As/GaAs quantum well, to numerically determine the potential profile, empty or occupied energy sub-bands, the wavefunctions and electron concentrations corresponding to each sub-band at various temperatures. Then assuming that the electron concentration is not altered, the variation of chemical potential with respect to both temperature and energy level-broadening parameter is studied under a uniform and constant magnetic field. …
Numerical Simulation Of Soliton Pulse Propagation In Doped Optical Fibres By Finite-Difference Method, Adams Usman, Junaidah Osman, D. R. Tilley
Numerical Simulation Of Soliton Pulse Propagation In Doped Optical Fibres By Finite-Difference Method, Adams Usman, Junaidah Osman, D. R. Tilley
Turkish Journal of Physics
We report results of applications of explicit finite-difference schemes, viz. the combination of forward-difference and central-difference approximation schemes, to study a simulation of soliton pulse propagation in saturable optical fibres. The dynamic governing equation is the saturable nonlinear Schrödinger equation (SNLE). This equation thus far lacks analytical solution in the sense of the inverse scattering method, although an analytical solitary wave solution is available. We use the localized solution to generate data for simulations of fundamental and second order soliton pulse propagation. In addition, we check the numerical accuracy of the results by considering the physical significance of two conserved …
Effect Of Iron Concentrations On Some Physical Properties Of The System Li_{0.5}Fe_{X}Ga_{2.5 - X}O_{4}, Abd El-Raouf Tawfik, N. Tashtoush, O.M. Hemeda
Effect Of Iron Concentrations On Some Physical Properties Of The System Li_{0.5}Fe_{X}Ga_{2.5 - X}O_{4}, Abd El-Raouf Tawfik, N. Tashtoush, O.M. Hemeda
Turkish Journal of Physics
A series of Li_{0.5} Fe_{x} Ga_{2.5 - x} O_{4} systems were prepared for x = 0, 0.25, 0.5, 0.75 and 1 by the general ceramic method. X-ray diffraction showed that all compositions have single phase Spinel cubic structure. The lattice parameter increased with enhancing iron concentration. The thermoelectric coefficient decreased with increasing x, and the majority carriers are holes. The increase of the jump length of hole increased the electrical conductivity. Jump-length increased with iron concentration and the rate of jumping gave rise to the electrical conductivity. The concentration of Fe^{3 +} ions in Lithium gallate is important, for such …
Amps-1d Modeling Of A-Si:H N^{+}-I-N^{+} Structure: The Validity Of Space Charge Limited Current Analysis, Aynur Eray, G. Nobile
Amps-1d Modeling Of A-Si:H N^{+}-I-N^{+} Structure: The Validity Of Space Charge Limited Current Analysis, Aynur Eray, G. Nobile
Turkish Journal of Physics
In this paper, the AMPS-1D (Analysis of Microelectronic and photonic structure) simulation program is used to understand the origin of the differences observed in Space Charge Limited Current (SCLC) analysis in thin and thick a-Si:H n^{ +} -i- n^{+} structure. For that purpose, the problem of applicability of SCLC measurements to n^{+}-i-n^{+} a-Si:H samples are investigated by using both the thin (0.3 \mu m) and thick (3 \mu m) samples. The simulation results show that activation energy in thick samples is larger than in thinner samples, which are an agreement with the experimental results. It is emphasized that this method …
Ac Conductivity And Dielectric Study Of Chalcogenide Glasses Of Se-Te-Ge System, Fathy Salman
Ac Conductivity And Dielectric Study Of Chalcogenide Glasses Of Se-Te-Ge System, Fathy Salman
Turkish Journal of Physics
The ac conductivity and dielectric properties of glassy system Se_{x}Te_{79 - x}Ge_{21}, with x = 11, 14, 17 at.%, has been studied at temperatures 300 to 450 K and over a wide range of frequencies (50 Hz to 500 kHz). Experimental results indicate that the ac conductivity and the dielectric constants depend on temperature, frequency and Se content. The conductivity as a function of frequency exhibited two components: dc conductivity \sigma _{dc}, and ac conductivity \sigma _{ac}, where \sigma _{ac} \sim \omega ^{s}. The mechanism of ac conductivity can be reasonably interpreted in terms of the correlated barrier hopping model …
Modeling Relaxation Length And Half-Thickness Of Wood By Method Of Gamma Radiation, Louis E. Akpabio, Sunday E. Etuk, Samuel David Ekpe
Modeling Relaxation Length And Half-Thickness Of Wood By Method Of Gamma Radiation, Louis E. Akpabio, Sunday E. Etuk, Samuel David Ekpe
Turkish Journal of Physics
Relaxation lengths and half-thickness values of different types of wood were determined using gamma radiation from ^{60}C0 source. Results show that oxystigma (Oxystima spp) has the highest relaxation length of 23.810cm, while mangrove (Rhizoohora spp) has the least relaxation length of 1.247 cm. Results also show that Oxystima (Oxystima spp) has the highest half thickness value of 16.500 cm and Mangrove (Rhizophora spp) has the least half-thickness value of 0.864 cm. Two mathematical models have been developed for the prediction or determination of density \rho, variation with relaxation length and half thickness value of wood. A good agreement (greater than …
Dielectric Properties And Conductivity Of Khco_3, Fathy Salman, S. Aboelhssan, Eslam Sheha, Mabrouk Elmansy
Dielectric Properties And Conductivity Of Khco_3, Fathy Salman, S. Aboelhssan, Eslam Sheha, Mabrouk Elmansy
Turkish Journal of Physics
KHCO_{3} compound was characterized in three principle realms: for its dielectric properties as a function of temperature and frequency in the ranges 300--370 K and 50 Hz to 1 MHz, respectively; bulk conductivity as a function of temperature, via impedance technique; and relaxation time as function of temperature. Variations of the bulk conductivity and relaxation time with temperature have been found to yield two segments, with two different activation energies. The activation energy for the two segments due to bulk conductivity have been found as 1.96 eV and 1.85 eV, while the activation energy due to relaxation have been found …
Formation And Elastic Behavior Of Lead-Magnesium Chlorophosphate Glasses, Hj. Ab. Aziz Sidek, S. P. Chow, Z. A. Talib, S. A. Halim
Formation And Elastic Behavior Of Lead-Magnesium Chlorophosphate Glasses, Hj. Ab. Aziz Sidek, S. P. Chow, Z. A. Talib, S. A. Halim
Turkish Journal of Physics
A series of ternary lead-magnesium chlorophosphate glasses, (PbCl_{2})_{x}(MgO)_{1 - x}(P_{2}O_{5})_{0.4}, of various compositions with 0.3 \le x \le 0.45 have been successfully prepared and their elastic properties have been characterized at room temperature. Results from the studies show that both the longitudinal and shear wave velocities decrease with increase of PbCl_{2} composition. The elastic constants C_{11}, C_{44} and Young's modulus show a decreasing trend while the elastic constant C_{12}, bulk modulus and Poisson's ratio show an increasing trend as the fraction of PbCl_{2} increases. This behavior of the elastic properties is related to the change in the structure of glasses …
The Normal And Inverted Meyer-Neldel Rule In The Ac Conductivity, Fouad Abdel-Wahab
The Normal And Inverted Meyer-Neldel Rule In The Ac Conductivity, Fouad Abdel-Wahab
Turkish Journal of Physics
Recently, a new approach has been proposed for the correlated barrier hopping (CBH) model where the ac relaxation time is thought to obey the Meyer-Neldel (MN) rule. This approach gives quantitative agreement with some reliable published experimental data. We report on an experiment involving the characterization of the ac conductivity of Se-Te thin films over a wide range of frequencies and temperatures, carried out in order to confirm applicability of the MN rule to the ac conductivity. In addition to the normal MN rule, the inverted MN rule was observed.
Design And Preparation Of Antireflection And Reflection Optical Coatings, Özlem Duyar, H. Zafer Durusoy
Design And Preparation Of Antireflection And Reflection Optical Coatings, Özlem Duyar, H. Zafer Durusoy
Turkish Journal of Physics
In this study, reflective and antireflective coatings were designed and simulated. Optical transmission and reflection values were deduced with a matrix formulation via a personal computer. It was found that the number of layers affects the optical performance. The width of the high-reflectance region in the reflectance curves decreases, while its height increases with the increasing number of layers for the reflective coating design. The antireflection coatings transmit about 99.89% in a broad high-pass band at the central wavelength of \lambda_{0} = 450 nm. In addition, simulated Fabry-Perot filters result in a single sharp transmittance peak at the desired central …
Realizations Of The Osp(2,1) Superalgebra And Related Physical Systems, Hayri̇ye Tütüncüler, Ramazan Koç
Realizations Of The Osp(2,1) Superalgebra And Related Physical Systems, Hayri̇ye Tütüncüler, Ramazan Koç
Turkish Journal of Physics
Eigenvalues and eigenfunction of two-boson 2 \times 2 Hamiltonians in the framework of the superalgebra osp(2,1) are determined by presenting a similarity transformation. The Hamiltonians include two bosons and one fermion have been transformed in the form of the one variable differential equations and the conditions for its solvability have been discussed. It is observed that the Hamiltonians of the various physical systems can be written in terms of the generators of the osp(2,1) superalgebra and under some certain conditions their eigenstates can exactly be obtained. In particular, the procedure given here is useful in determining eigenstates of the Jaynes-Cummings …
On Electron Mobility In A Rectangular Quantum Wire Due To Alloy Disorder, Guseyn Behbudoglu Ibragimov
On Electron Mobility In A Rectangular Quantum Wire Due To Alloy Disorder, Guseyn Behbudoglu Ibragimov
Turkish Journal of Physics
Analytic expressions are derived to describe the electron mobility and relaxation rate in the rectangular quantum wire experiencing scattering due to alloy disorder. The dependence of electron mobility on the temperature and transverse dimension is numerically evaluated and it is found that the mobility increases continuously with temperature, because there is no new intersubband scattering with increase in temperature. It is shown that the alternating increase/decrease in the mobility---depending on the transverse dimension of the quantum wire---occurs due to intersubband scattering. It is found that the mobility in a quantum wire is significantly greater than mobility in a quantum well.
Raman Scattering In Layered Cdingas_4, Aydin Kulibekov
Raman Scattering In Layered Cdingas_4, Aydin Kulibekov
Turkish Journal of Physics
Raman scattering spectra of CdInGaS_4 crystals grown by the chemical transport method were measured at room and liquid-nitrogen temperatures. Band pairs at 29-38, 43-48 and 60-65 cm^{-1} are reported for the first time. The origin of these bands is attributed to the Davydov doublets, arising due to a small interlayer interaction. Seventeen bands observed in the Raman spectra are assigned to normal modes on the basis of the C_{3v}^1 space group. This modification contains two layers per unit cell and do not have inversion symmetry. It is shown that the crystals grown from the vapor phase and by the Bridgman …
On Hamiltonian Formulation Of Non-Conservative Systems, Eqab M. Rabei, Tareq S. Alhalholy, A. A. Taani
On Hamiltonian Formulation Of Non-Conservative Systems, Eqab M. Rabei, Tareq S. Alhalholy, A. A. Taani
Turkish Journal of Physics
Fractional derivatives are used to construct the Lagrangian and the Hamiltonian formulation for non-conservative systems. To clarify the theory of Riewe two interesting examples are given. The potentials are obtained using the Laplace transform operator for fractional derivatives and the Lagrangian and Hamiltonian formulations are constructed for the two systems. Besides, it is shown that the Hamilton equations of motion are in agreement with the Euler-Lagrange equations for these systems.
Comparative Study Of First Two Harmonics In Cosmic Ray Intensity For The Period 1964-95, Rekha Agarwal Mishra, Rajesh K. Mishra
Comparative Study Of First Two Harmonics In Cosmic Ray Intensity For The Period 1964-95, Rekha Agarwal Mishra, Rajesh K. Mishra
Turkish Journal of Physics
The Deep River neutron monitor data has been harmonically analyzed for the period 1964--95 covering three solar cycles 20, 21 and 22, looking for a long term trend of the diurnal and semi-diurnal anisotropies of cosmic ray intensity on geomagnetically 60 quiet days. The amplitude of both the harmonics remains statistically constant during 1964-70. The amplitudes of the first harmonic is found to be low during 1965, 1967, 1976-77, 1986-87, 1991, 1993 and 1995. The amplitude of diurnal anisotropy acquired exceptionally large values in 1985, whereas semi-diurnal anisotropy acquired large values in 1974-75 and in 1984, which coincided with epochs …
A Novel Radiative Substrate Heater, Abdullah Ceylan, Erdal Kaynak, Şadan Özcan, Tezer Firat
A Novel Radiative Substrate Heater, Abdullah Ceylan, Erdal Kaynak, Şadan Özcan, Tezer Firat
Turkish Journal of Physics
In this work, we have developed a new low cost radiative substrate heater for deposition of high-T_c superconducting thin films. It has all the features required for the preparation of high quality superconducting thin films. It is possible to reach ~ 800 °C substrate temperature with it by using only one 250 W halogen projector bulb.
Some New Mathematical Results Obtained Using Closure, Harry A. Mavromatis
Some New Mathematical Results Obtained Using Closure, Harry A. Mavromatis
Turkish Journal of Physics
Several new mathematical sum rules are derived using closure. Their convergence and other properties are then discussed.
Track Registration Characteristics Of Low-Energy Protons In Cellulose Nitrate (Cn-85), Arif Mahmood, Shazia Bashir, Attiq Us-Salam, Faizan Ul-Haq
Track Registration Characteristics Of Low-Energy Protons In Cellulose Nitrate (Cn-85), Arif Mahmood, Shazia Bashir, Attiq Us-Salam, Faizan Ul-Haq
Turkish Journal of Physics
We describe our efforts to determine the most important track registration parameters for the suitable use of CN-85 track detectors in the registration of low energy protons.
Analysis Of Rgu Photometry In Selected Area 51, Selçuk Bi̇li̇r, Sali̇h Karaali̇, R. Buser
Analysis Of Rgu Photometry In Selected Area 51, Selçuk Bi̇li̇r, Sali̇h Karaali̇, R. Buser
Turkish Journal of Physics
A low-latitude anticenter field (l = 189°, b = +21°) is investigated by using the full calibration tools of RGU photometry. The observed RGU data are reduced to the standard system and the separation of dwarfs and evolved stars is carried out by an empirical method. Stars are categorized into three metallicity classes, i.e. -0.25
Empirical Models For The Correlation Of Monthly Average Daily Global Solar Radiation With Hours Of Sunshine On A Horizontal Surface At Karachi, Pakistan, Firoz Ahmed, Intikhab Ulfat
Empirical Models For The Correlation Of Monthly Average Daily Global Solar Radiation With Hours Of Sunshine On A Horizontal Surface At Karachi, Pakistan, Firoz Ahmed, Intikhab Ulfat
Turkish Journal of Physics
A new set of constants for Angstrom-type correlation of first and second order, to estimate monthly average daily global solar radiation, has been obtained employing sunshine hours data recorded at Karachi, Pakistan (Lat. 24^° 54' N, Long. 67^° 08' E). Least square regression is performed to derive these constants. The correlation equations developed are employed to calculate the monthly average daily global solar radiation. These results are then compared with various other existing correlations and the measured data. Excellent agreement has been found between the estimated and the measured values.
Physical Characteristics Of Polymer Magnetic Microspheres, Rasim A. Ali-Zade
Physical Characteristics Of Polymer Magnetic Microspheres, Rasim A. Ali-Zade
Turkish Journal of Physics
In this study the structure and the magnetic properties of polymer microspheres, filled with magnetite nanoparticles are investigated. Average particle size of magnetite nanoparticles before and after being introduced into polymer microspheres, and the distance between nanoparticles in the polymer microspheres, are measured. Magnetization curve of polymer magnetic microspheres (PMMS) is determined. The magnetic susceptibility of PMMS with various diameters, and the dependence of PMMS magnetic susceptibility on diameter are determined. Magnetization occurs due to the orientation of PMMS as a magnetic moment. The total magnetic moment of PMMS is the sum of magnetic moments of PMMS sections which consist …
Simulation Of Millimeter-Wave Gunn Oscillations In Gallium Nitride, Cem Sevi̇k, Ceyhun Bulutay
Simulation Of Millimeter-Wave Gunn Oscillations In Gallium Nitride, Cem Sevi̇k, Ceyhun Bulutay
Turkish Journal of Physics
High field transport in wide bandgap semiconductors like GaN is of great technological importance. The negative differential mobility regime at high fields, under suitable conditions, can lead to millimeter-wave Gunn oscillations. Using extensive simulation based an ensemble Monte Carlo technique, the prospects of GaN Gunn diodes are theoretically investigated. The possibility of operating these Gunn diodes at their higher harmonic modes are explored. The main finding of this research is that the carrier dynamics in GaN can be tailored by an optimum choice of doping profile, temperature and bias conditions so that the efficiency of higher harmonic Gunn oscillations can …
Structural Characterization And Magnetization Of Mg_{0.5}Cu_{0.5}Y_{X}Fe_{2-X}O_4 Ferrites, Mansour Al-Haj
Structural Characterization And Magnetization Of Mg_{0.5}Cu_{0.5}Y_{X}Fe_{2-X}O_4 Ferrites, Mansour Al-Haj
Turkish Journal of Physics
Mg_{0.5}Cu_{0.5}Y_xFe_{2-x}O_4 ferrites were prepared by the solid state reaction method and were characterized by X-ray diffraction and magnetization measurements. A single spinel phase was obtained in the range 0 \le x \le 0.08. The lattice parameter was found to increase with the increase of x except at x = 0.08, which may indicate a distortion in the spinel lattice. The saturation magnetization was found to decrease with increasing x due to replacement of the magnetic Fe^{3+} ions by the nonmagnetic Y^{3+} ions.
Quantum Statistical Entropy Of Sen Black Hole, Zhao Ren, Wu Yueqin, Zhang Lichun
Quantum Statistical Entropy Of Sen Black Hole, Zhao Ren, Wu Yueqin, Zhang Lichun
Turkish Journal of Physics
In this paper, by using quantum statistical methods, we directly obtain the partition function of Bose field and Fermi field on the background of the axisymmetrical Sen black hole. The difficult-to-solve wave equation is avoided. Then via the improved brick-wall method and membrane model, we calculate the entropy of Bose field and Fermi field of the black hole. We find that the entropy of the black hole is proportional to the area of the horizon. In our results, we do not encounter the left out term nor the divergent logarithmic term that appears in the original brick-wall method. The question …
Structural And Magnetic Properties Of Co_{0.6}Znn_{0.4}Mn_{X}Fe_{2 - X}O_{4}, O.M. Hemeda
Structural And Magnetic Properties Of Co_{0.6}Znn_{0.4}Mn_{X}Fe_{2 - X}O_{4}, O.M. Hemeda
Turkish Journal of Physics
A series of Co-Zn ferrite samples substituted by Mn were prepared by the usual double sintering ceramic technique. The x-ray diffraction patterns of the samples confirmed the formation of single-phase spinel structure, and x-ray analysis supply data that suggests the cation distribution of the material. The tetrahedral and octahedral radius permits one to calculate the theoretical lattice parameter and the bond lengths Fe-O at A and B sites. The particle size of the given samples was measured from the Scherer equation and a correlation was found between particle size, and structural and magnetic properties. The XRF confirmed the presence of …
The Born Scattering Amplitude Of A Non-Relativistic Spin One-Half Particle In An Aharonov-Bohm Potentia, Yousef Romia, Mohammad Shikakhwa
The Born Scattering Amplitude Of A Non-Relativistic Spin One-Half Particle In An Aharonov-Bohm Potentia, Yousef Romia, Mohammad Shikakhwa
Turkish Journal of Physics
The Born scattering amplitude of a non-relativistic spin one-half particle in an Aharonov-Bohm potential is calculated up to second order. It is demonstrated that perturbation theory works well for this model, in contrast with the case of scalar particles, thanks to the spin-magnetic moment interaction term. The first order amplitude is shown to coincide with the exact amplitude when expanded to the same order; the second order amplitude is finite and null. The polarized scattering cross section is found to be different from the unpolarized one only if the incident particle has a spin component perpendicular to the flux tube.
Large Amplitude Wave Trains In Cosmic Ray Intensity, Rajesh K. Mishra, Rekha Agarwal Mishra
Large Amplitude Wave Trains In Cosmic Ray Intensity, Rajesh K. Mishra, Rekha Agarwal Mishra
Turkish Journal of Physics
Using ground-based neutron monitor data of Deep River, the high amplitude anisotropic wave train events (HAE) in cosmic ray intensity have been investigated during the period 1991--1994. It has been observed that the phase of diurnal anisotropy for majority of HAE cases remains in the same co-rotational direction, whereas for some HAE cases the phase of diurnal anisotropy has shifted to later hours. For the majority of HAE cases the amplitude of semi-diurnal anisotropy remains statistically the same, whereas the phase of semi-diurnal anisotropy for all HAE cases has shifted to later hours. Furthermore, for tri-diurnal anisotropy the phase shifts …
Charged Particle--Image Interaction Near A Conducting Surface, Ersen Mete, Meti̇n Durgut
Charged Particle--Image Interaction Near A Conducting Surface, Ersen Mete, Meti̇n Durgut
Turkish Journal of Physics
The interaction of a bulk electron with conducting surfaces is studied by means of the Bohm-Pines transformation in the second quantization formalism. The effective interaction potentials are obtained for the case of one plane and two plane configurations in the form of electron-image electron scattering.
E2/M1 Multipole Mixing Ratios Of Transitions In Erbium Isotopes, Harun Reşi̇t Yazar, İhsan Uluer
E2/M1 Multipole Mixing Ratios Of Transitions In Erbium Isotopes, Harun Reşi̇t Yazar, İhsan Uluer
Turkish Journal of Physics
Erbium isotopes (Z = 64) lie in the transitional region that occurs at the middle of the range of deformed nuclei. \gamma -ray E2/M1 mixing ratios for selected transitions in ^{166-168}Er are calculated in the proton-neutron interacting boson approximation(IBA-2). The results obtained for ^{166 -168}Er are reasonably in good agreement with the previous experimental and teoretical values.
Solution Of The Schrödinger Equation With One And Two Timensional Double-Well Potentials, Ramazan Koç, Derya Haydargi̇l
Solution Of The Schrödinger Equation With One And Two Timensional Double-Well Potentials, Ramazan Koç, Derya Haydargi̇l
Turkish Journal of Physics
The Schrödinger equation with one and two dimensional potentials are solved in the framework of the sl_2(R) Lie algebra. Eigenfunctions of the Schrödinger equation for various asymmetric double-well potentials have been determined and the eigenstates are expressed in terms of the orthogonal polynomials. The solution of the double-well potential in two dimension have been analyzed.