Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 39

Full-Text Articles in Physics

Electric Multipole Moments Of Some Diatomic Molecules Molecules, M. Özgür Sezer, Ayhan Özmen, Hüseyi̇n Yüksel Jan 2009

Electric Multipole Moments Of Some Diatomic Molecules Molecules, M. Özgür Sezer, Ayhan Özmen, Hüseyi̇n Yüksel

Turkish Journal of Physics

Molecular Electric Multipole Moment (MEMM) integrals have been derived for diatomic molecular systems, and then some lower multipole moments as dipole moments and quadrupole moments have been calculated for some diatomic molecules. The calculations have been performed by using our analytical formula over Slater-Type orbitals (STOs) with Cade and Huo's basis sets and the GAMESS program package working with Gaussian-Type basis sets (GTOs). The expressions which involve factorials are given in terms of binomial coefficients in order to speed up calculations. The results have been obtained in agreement with data found in the literature.


Kantowski-Sachs Viscous Fluid Cosmological Model With A Varying \Lambda, Sharad Kandalkar, Pramod Khade, Sunita Gawande Jan 2009

Kantowski-Sachs Viscous Fluid Cosmological Model With A Varying \Lambda, Sharad Kandalkar, Pramod Khade, Sunita Gawande

Turkish Journal of Physics

We study the Kantowski-Sachs cosmological model filled with viscous fluid in the presence of cosmological term \Lambda. To get a deterministic solution, a condition between metric potentials is used. The viscous coefficient of bulk viscous fluid is assumed to be a power function of mass density, whereas coefficient of shear viscosity is considered proportional to scale of expansion in the model. It is found that the cosmological constant \Lambda is positive and is a decreasing function of time, which is supported by results from recent supernova observations. Some physical and geometrical properties of the models are also discussed.


Exact Peaked Wave Solution Of The Osmosis K(2,2) Equation, Xijun Deng, Libo Han Jan 2009

Exact Peaked Wave Solution Of The Osmosis K(2,2) Equation, Xijun Deng, Libo Han

Turkish Journal of Physics

By using the first-integral method, an exact peaked wave solution to the K(2,2) equation with osmosis dispersion has been obtained directly. The obtained solution agrees well with the previously known solution in the literature. The first integral method is easier and quicker than other traditional techniques. It is shown that the first integral method is a standard and direct method, which may allow us to solve other more complicated solitary wave problems.


Dielectric Properties Of Liquid Systems: The Ideal Complex Permittivity In Liquid Mixtures, Adrian H. Buep Jan 2009

Dielectric Properties Of Liquid Systems: The Ideal Complex Permittivity In Liquid Mixtures, Adrian H. Buep

Turkish Journal of Physics

A general definition for ideal complex permittivity in a liquid mixture was reached by considering a thermodynamically ideal mixture under the effect of an applied harmonic electric field. The resulting definition is independent of any particular dielectric model, as well as the polarity of the components.


Heavy Ion Reactions Producing A Heavier Deformed Nucleus And Free Nucleons, Ahmed Osman Jan 2009

Heavy Ion Reactions Producing A Heavier Deformed Nucleus And Free Nucleons, Ahmed Osman

Turkish Journal of Physics

Carbon induced heavy ion reactions on the heavy ^{197}Au target are considered. The statistical scission model is used to calculate this fission process. In the present considered reactions, the process leads to the fragmentation of only one deformed heavy fragment and few nucleons. Angular distributions of the fission fragments are numerically calculated for different values of the incident energies in the range 64-104 MeV. The present theoretical calculations of the differential cross-sections are in good agreements with experimental data for the carbon incident energy 84 A MeV. The effective variance of this fission process is also calculated. The present numerically …


Measurements Of K-Shell Fluorescence Yields For Ti, V, Cr, Fe, Co, Ni And Cu Elements And Their Halogen Compounds, Eli̇f Baydaş, Eli̇f Orhan Öz, Mehmet Büyükyildiz Jan 2009

Measurements Of K-Shell Fluorescence Yields For Ti, V, Cr, Fe, Co, Ni And Cu Elements And Their Halogen Compounds, Eli̇f Baydaş, Eli̇f Orhan Öz, Mehmet Büyükyildiz

Turkish Journal of Physics

K-shell fluorescence yields \omega_K were measured for the elements Ti, V, Cr, Fe, Co, Ni, Cu and F and Cl compounds of these elements. Measurements were carried out at 10 keV excitation energy using secondary excitation method. K x-rays emitted by samples were counted by a Si(Li) detector with 160 eV resolution at 5.9 keV. Measurement of K-shell fluorescence yields \omega_K for these elements are compared with earlier experimental results obtained by other methods.


Cd_{1-X}Mn_Xs Dilute Magnetic Semiconductor: Application In Photoelectrochemical Cells, J. S. Dargad, L. P. Deshmukh Jan 2009

Cd_{1-X}Mn_Xs Dilute Magnetic Semiconductor: Application In Photoelectrochemical Cells, J. S. Dargad, L. P. Deshmukh

Turkish Journal of Physics

A new class of dilute magnetic semiconductor (DMS, CdMnS) thin film based photoelectrochemical cell is presented. DMS thin films are synthesized on both glass and stainless steel substrates using a chemical growth process. The preparation parameters, such as growth temperature, time, reaction pH, precursor concentrations, etc., were optimized to yield characteristically oriented films. The layer thickness was found to decrease with increase in Mn^{2+} concentration. Composition of the as-grown samples was determined by an EDS technique. The electrochemical cells were then formed out of these series of films as the active photoelectrodes, an electrolyte and a counter electrode. The cells …


Tau Sleptons And Tau Sneutrino Decays In Mssm Under The Cosmological Bounds, Levent Selbuz, Z. Zekeri̇ya Aydin Jan 2009

Tau Sleptons And Tau Sneutrino Decays In Mssm Under The Cosmological Bounds, Levent Selbuz, Z. Zekeri̇ya Aydin

Turkish Journal of Physics

We present a numerical investigation of the fermionic two-body decays of tau sleptons \tilde \tau_{1,2} and \tau sneutrino in the Minimal Supersymmetric Standard Model with complex parameters. In the analysis we particularly take into account the cosmological bounds imposed by WMAP data. We plot the CP-phase dependences for each fermionic two-body channel of \tilde \tau_{1,2} and \tau sneutrino and speculate about the branching ratios and total (two-body) decay widths. We find that the phase dependences of the decay widths of the third family sleptons are quite significant which can provide viable probes of additional CP sources. We also draw attention …


Conversion Efficiency Calculations For Euv Radiation Emitted From Laser-Produced Tin Plasmas, Betül Atalay, Necla Kenar, Ari̇f Demi̇r Jan 2009

Conversion Efficiency Calculations For Euv Radiation Emitted From Laser-Produced Tin Plasmas, Betül Atalay, Necla Kenar, Ari̇f Demi̇r

Turkish Journal of Physics

Ni-like and Co-like EUV radiation between 11--17 nm emitted from laser produced tin plasmas was modelled by using the hydrodynamic/atomic physics code EHYBRID. The atomic data were obtained using the Cowan code. The effects of driving laser pulse duration and the laser intensity with different wavelengths were investigated. The maximum conversion efficiency was calculated as 13.4% for a 266 nm Nd:YAG laser with 1 \times 10^{13} W/cm^2 pulse intensity and 5 ns pulse duration.


Superconducting State Parameters Of Al-Li Binary Alloys, Aditya M. Vora Jan 2009

Superconducting State Parameters Of Al-Li Binary Alloys, Aditya M. Vora

Turkish Journal of Physics

Theoretical computation of superconducting state parameters (SSP) viz. electron-phonon coupling strength \lambda , Coulomb pseudopotential \mu^* , transition temperature T_C , isotope effect exponent \alpha and effective interaction strength N_o V of face centered cubic Al_{1-C} Li_C binary alloys have been made extensively in the present work using a model potential formalism for the first time. A considerable influence of various exchange and correlation functions on \lambda and \mu^* is found from the present study. The present results of the SSP are found in qualitative agreement with the available experimental data wherever exist.


Asphericity In The Fermi Surface Of D And F-Shell Metals, J. K. Baria, A. R. Jani Jan 2009

Asphericity In The Fermi Surface Of D And F-Shell Metals, J. K. Baria, A. R. Jani

Turkish Journal of Physics

Recently proposed pseudopotential has been used to calculate asphericity in the Fermi surface of d and f-shell metals along the three symmetry directions [100], [110] and [111]. The parameter of the potential has been determined by zero pressure condition and the exchange and correlation function due to Taylor has been incorporated. The present results are in good agreement with experimental findings for Cu, Ag, Au and Pd; while for other d and f- shell metals we could not found sufficient theoretical as well as experimental data for the asphericity in the Fermi Surface in order to workout a quantitative comparison. …


Energy Levels Of The 6p_{3/2}Ns, Nd, Ng Autoionizing Series Of Pb I, Chao Zhou, Liang Liang, Ling Zhang Jan 2009

Energy Levels Of The 6p_{3/2}Ns, Nd, Ng Autoionizing Series Of Pb I, Chao Zhou, Liang Liang, Ling Zhang

Turkish Journal of Physics

Based on the weakest bound electron potential model (WBEPM) theory, six energy levels of the autoionizing Rydberg series 6pns 3/2[3/2]_1 (n = 15-25), 6pns 3/2[3/2]_2 (n = 15-25), 6pnd 3/2[3/2]_1 (n = 13-25), 6pnd 3/2[5/2]_3 (n = 13-25), 6pnd 3/2[7/2]_3 (n = 14-25) and 6png 3/2[5/2]_2 (n = 5-25) of Pb I are calculated. Foreign level perturbation corrections are taken into account in calculations of four series among them. The theoretical calculated results are in good agreement with the known experimental data, and some energies without experimental values are predicted.


Prediction Of The Pressure-Induced Phase Transition In Gaas By The Positron Affinity, Belabbes Soudini Jan 2009

Prediction Of The Pressure-Induced Phase Transition In Gaas By The Positron Affinity, Belabbes Soudini

Turkish Journal of Physics

The thermalized positron charge distribution is calculated as a function of pressure variation in GaAs. Calculations have been carried out via the independent particle method (IPM) coupled with the empirical pseudopotential method (EPM). Initial results show a clear asymmetrical positron charge distribution relative to the bond center. From this positron affinity we have calculated the ionicity character with respect to the pressure variation using our empirical formula. Our results show an agreement with the thermochemical phase diagram proposed by Phillips.


Structural And Magnetic Properties Of Mg_{0.8-X}M_{0.2}Ni_Xfe_2o_4 (M = Zn, Mn) Ferrite Powders, Mansour Al-Haj Jan 2009

Structural And Magnetic Properties Of Mg_{0.8-X}M_{0.2}Ni_Xfe_2o_4 (M = Zn, Mn) Ferrite Powders, Mansour Al-Haj

Turkish Journal of Physics

Structural and magnetic properties of Mg_{0.8-x}M_{0.2}Ni_xFe_2O_4 (M = Zn, Mn; x = 0, 0.2, 0.4, 0.6, 0.8) ferrite powders, prepared by solid state reaction method, were studied. The variations of lattice parameter, X-ray density, crystallite size, saturation magnetization, effective number of Bohr magneton, and coercivity with Ni content were investigated. The role of grain size was found to be crucial in the behavior of coercivity.


Tilted Bianchi Type I Dust Fluid Magnetized Cosmological Model In General Relativity, Anita Bagora, Ghanshyam Singh Rathore, Pushpa Bagora Jan 2009

Tilted Bianchi Type I Dust Fluid Magnetized Cosmological Model In General Relativity, Anita Bagora, Ghanshyam Singh Rathore, Pushpa Bagora

Turkish Journal of Physics

Tilted Bianchi Type I perfect fluid cosmological model in presence of magnetic field is investigated. To get a determinate solution, we assume p = 0 and A = BC, where A, B and C are metric potentials. A special model is also investigated in the absence of magnetic field. The various physical and geometrical aspects of both the models are also discussed. The effect of the magnetic field on the model is also discussed.


Effect Of A Wiggler Magnetic Field And The Ponderomotive Force On The Second Harmonic Generation In Laser-Plasma Interactions, Hassan Ranjbar Askari, Maryam Noroozi Jan 2009

Effect Of A Wiggler Magnetic Field And The Ponderomotive Force On The Second Harmonic Generation In Laser-Plasma Interactions, Hassan Ranjbar Askari, Maryam Noroozi

Turkish Journal of Physics

In this paper, we consider second harmonic generation and its phase-matching in an underdense plasma in the presence of a wiggler magnetic field. Wiggler magnetic field plays both a dynamic role in producing the traverse harmonic current and a kinematical role in ensuring phase-matching. The inertial ponderomotive force \rho (\vec{u} . \vec \nabla) \vec{u} is a source of harmonic generation. \vec{u} beats with itself to produce a different harmonic. The inertial ponderomotive force can also affect the efficiency of second harmonic generation; and its effect on second harmonic generation is also considered.


First-Principles Study Of Cubic B_Xin_{1-X}N Alloys, Abdelhadi Lachebi, Mohamed Sehil, Hamza Abid Jan 2009

First-Principles Study Of Cubic B_Xin_{1-X}N Alloys, Abdelhadi Lachebi, Mohamed Sehil, Hamza Abid

Turkish Journal of Physics

The first ab-initio calculations were carried out for the electronic and structural properties of BInN boron ternary alloys. The full potential linearized augmented plane wave (FP-LAPW) method was employed within density functional theory (DFT). We have investigated the lattice parameters and band gap energies. The lattice constant a exhibits a small downward bowing. The calculated band gap variation gives a small bowing in good agreement with the experimental reports. We notice a direct to indirect band gap crossover at x = 0.83.


Signature Splitting And Signature Inversion Of Rotational Bands In Odd-Odd Nuclei In Rare-Earth Region, Manal Mahmoud Sirag Jan 2009

Signature Splitting And Signature Inversion Of Rotational Bands In Odd-Odd Nuclei In Rare-Earth Region, Manal Mahmoud Sirag

Turkish Journal of Physics

Anomalous signature splitting and signature inversion for the configuration \pi h_{11/2} \otimes \nu i_{13/2} in rotational bands of odd-odd nuclei have been studied using the energy staggering index S(I) as a function of spin I. The unfavored signature index was found lying lower than the favored one. A systematic look at the features of this signature inversion in a series of nine lighter rare earth nuclei in the region around A \sim 160 (Z~=~65-75, N~=~89-101) are presented. The analysis reveals an anomalous signature splitting for this configuration. The magnitude of signature splitting at low spins decreases as the proton number …


Transport Property Measurements Of Bi_2se_3 Crystal Grown By Bridgman Method, M. P. Deshpande, Nilesh N. Pandya, M. N. Parmar Jan 2009

Transport Property Measurements Of Bi_2se_3 Crystal Grown By Bridgman Method, M. P. Deshpande, Nilesh N. Pandya, M. N. Parmar

Turkish Journal of Physics

This paper deals with the growth of Bi_2Se_3 crystal by newly designed experimental set-up of Bridgman technique in our laboratory. Grown crystal is characterized by EDAX (Energy Dispersive Analysis of X-rays), XRD (X-ray Diffraction), low temperature thermopower measurements (17-284 K), resistivity measurements (16-294 K) and Hall Effect at room temperature in order to study its various properties. The surface study of the grown crystal using AFM (Atomic Force Microscopy) shows a hexagonal unit cell shape whose internal angle determined comes out to be nearly equal to 122.94° which has close resemblance with an angle of 120° of perfect internal angle …


Partition Function Of The Harmonic Oscillator On A Noncommutative Plane, Iraj Jabbari, Akbar Jahan, Zafar Riazi Jan 2009

Partition Function Of The Harmonic Oscillator On A Noncommutative Plane, Iraj Jabbari, Akbar Jahan, Zafar Riazi

Turkish Journal of Physics

We derive the partition function of the one-body and two-body systems of classical noncommutative harmonic oscillator in two dimensions. Then, we employ the path integral approach to the quantum noncommutative harmonic oscillator and derive the partition function of the both systems at finite temperature.


Vibrational Analysis Of Flavone, Yusuf Erdoğdu, Ozan Ünsalan, M. Tahi̇r Güllüoğlu Jan 2009

Vibrational Analysis Of Flavone, Yusuf Erdoğdu, Ozan Ünsalan, M. Tahi̇r Güllüoğlu

Turkish Journal of Physics

In this study, the experimental and theoretical study on the structures and vibrations of flavone are presented. FT-IR and FT-Raman spectra of the molecule have been recorded in the 400-4000 cm^{-1} region and the 5-3500 cm^{-1} region, respectively. The molecular geometry and vibrational frequencies of flavone in the ground state have been calculated by using Density Functional method (B3LYP) in conjunction with 6-311++G(d,p) and 6-31++G(d) as basis sets.


First-Principles Calculations Of Structural, Electronic And Optical Properties Of Zinc-Blende Si_X Ge_{1-X} C Alloys, Ahmed Djedid, Boucif Abbar, Oukacha Abbes Jan 2009

First-Principles Calculations Of Structural, Electronic And Optical Properties Of Zinc-Blende Si_X Ge_{1-X} C Alloys, Ahmed Djedid, Boucif Abbar, Oukacha Abbes

Turkish Journal of Physics

We present first-principles calculations of the structural, electronic and optical properties of zinc-blende Si_x Ge_{1-x} C alloys by application of the full potential linearized augmented plane wave (FP-LAPW) method. In this approach, the generalized gradient approximation was used for the exchange-correlation energy which is based on the optimization of total energy and corresponding potential. The effect of composition on lattice constants, bulk modulus, band gap, real part of the dielectric function \varepsilon \left(0 \right) and refractive index n(0) was investigated. These parameters were found to depend nonlinearly on alloy composition x, except the bulk modulus and the lattice parameter, which …


On Some Properties Of The Neutrino In The Early Universe, S. Mani, A. Sagari, B. Chakrabarti, A. Bhattacharya Jan 2009

On Some Properties Of The Neutrino In The Early Universe, S. Mani, A. Sagari, B. Chakrabarti, A. Bhattacharya

Turkish Journal of Physics

Properties of the neutrino in the early universe have been investigated incorporating a small inhomogeneity in the mass density of the early universe. Dependence on this factor is found in studying mean free path and mass bound of neutrinos. The mass bound of neutrino is found to be in the range between 14 MeV and 76 MeV corresponding to the radiation and matter dominated eras respectively. The oscillation length for neutrinos have been estimated to be 86 km for beam energy 2.754 MeV and 220 km for beam energy 7 MeV.


Thermodynamic Properties Of Quasi-Equilibrium Magnons In Crystalline Bulk Materials And Thin Films, Ahmed Sayed Hassan, A. M. El-Badry Jan 2009

Thermodynamic Properties Of Quasi-Equilibrium Magnons In Crystalline Bulk Materials And Thin Films, Ahmed Sayed Hassan, A. M. El-Badry

Turkish Journal of Physics

The temperature dependence of spontaneous magnetization and specific heat for a system of magnons are investigated systematically. The correspondence of this system with the Bose-Einstein condensation phenomenon is used. Calculations are performed for both crystalline bulk materials and thin films. The calculated results are consistent with the available experimental data, indicating that our suggested approach is a suitable one for describing the thermodynamic properties for the magnon system. The thermodynamical parameters for magnons system have many similarities with the thermodynamical parameters for boson atomic gas. Results for crystalline bulk material can be used as a zeroth order approximation in any …


Effective Width And Expansion Energy Of The Interacting Condensed ^{87}Rb Bose Gas With Finite Size Effects, Ahmed Sayed Hassan, A. M. El-Badry Jan 2009

Effective Width And Expansion Energy Of The Interacting Condensed ^{87}Rb Bose Gas With Finite Size Effects, Ahmed Sayed Hassan, A. M. El-Badry

Turkish Journal of Physics

This work is devoted to study the temperature dependence of the effective width and expansion energy on the finite size and interaction effects (repulsive interactions). It is found that the effective size , and expansion energy in the radial direction E_y of a Bose gas follow a characteristic temperature dependence, i.e. , E_y \propto (T/T_0)^4 if T_0 < T and , E_y \propto (T/T_0) if T_0 > T. Our results show that these two parameters increases with the number of atoms, and with increasing repulsive interaction strength at temperature less than the transition temperature, (T < T_o); yet it has little effect at temperatures higher than the transition temperature (T > T_o). The obtained results are compared with the available experimental data for ^{87}Rb directly, full …


Studies On Physical Properties And Carrier Conversion Of Sno_2:Nd Thin Films, Jochan Joseph, Varghese Mathew, Jacob Mathew, K. E. Abraham Jan 2009

Studies On Physical Properties And Carrier Conversion Of Sno_2:Nd Thin Films, Jochan Joseph, Varghese Mathew, Jacob Mathew, K. E. Abraham

Turkish Journal of Physics

Neodymium (Nd)-doped SnO_2 transparent conducting oxide thin films were prepared by vapour deposition technique under different deposition parameters: substrate temperature, time and flow rate of vapour deposition, amount of base material, distance between the substrate and spray gun tip, and dopant (Nd) concentration. The structural, optical, electrical and photo-electronic properties of the doped and undoped SnO_2 films were studied. X-ray diffraction studies shows the polycrystalline nature of the films with preferential orientation along the (101), (211) and (301) planes and an average grain size of 100 Å. The optical properties of these films were studied by measuring their optical transmission …


Unsteady Free Convection Flow With Thermal Radiation Past A Vertical Porous Plate With Newtonian Heating, Promise Mebine, Emmanuel Munakurogha Adigio Jan 2009

Unsteady Free Convection Flow With Thermal Radiation Past A Vertical Porous Plate With Newtonian Heating, Promise Mebine, Emmanuel Munakurogha Adigio

Turkish Journal of Physics

This paper considers exact solutions of unsteady free convection flow with thermal radiation past a vertical porous plate with Newtonian heating. The technique of Laplace transform was employed in deriving the solutions to the governing flow and energy equations. A parametric study of all parameters involved was conducted, and a representative set of results showing the effect of the radiation parameter N, the ratio of uniform suction to characteristic velocity parameter R, and the free convection parameter Gr on the velocity and temperature are illustrated graphically. The skin friction or shear and heat flux are discussed quantitatively. It is evident …


The Electrical Conduction Mechanisms And Thermoelectric Power Of Snse Single Crystals, M. M. Nassary Jan 2009

The Electrical Conduction Mechanisms And Thermoelectric Power Of Snse Single Crystals, M. M. Nassary

Turkish Journal of Physics

Single crystals of SnSe were prepared in our laboratory by a special modified Bridgman technique. Measurements of the electrical conductivity and Hall effect between 141 K and 553 K were carried out on SnSe sample in two crystallographic directions. The investigated sample was found to be of p-type conductivity. The Hall mobilities parallel and perpendicular to layers plane at room temperature, were 7835.9 cm^2/ V \cdots and 7274.7 cm^2/ V.s, respectively. The free carrier concentration P = 3.52 \times 10^{12} cm^{-3} at room temperature. Also, the thermoelectric power (TEP) was investigated in the temperature range from 176 to 553 K. …


Thermoelectric Power And Low-Field Electron Mobility In Al_Xga_{1-X}N Lattice-Matched To Gan, H. Arabshahi Jan 2009

Thermoelectric Power And Low-Field Electron Mobility In Al_Xga_{1-X}N Lattice-Matched To Gan, H. Arabshahi

Turkish Journal of Physics

The results of thermoelectric power and electron drift mobility in Al_xGa_{1-x}N lattice-matched to GaN are calculated for different temperatures, free-electron concentrations and compositions. The two-mode nature of the polar optic phonons is considered jointly with deformation potential acoustic, piezoelectric, alloy and ionized-impurity scattering. Band non-parabolicity, admixture of p functions, arbitrary degeneracy of the electron distribution and the screening effects of free carriers on the scattering probabilities are incorporated. The Boltzmann equation is solved by an iterative technique using the currently established values of the material parameters. The iterative results are in fair agreement with other recent calculations obtained using the …


General Formulation Of The Scattered Matter Waves By A Quantum Shutter, Yusuf Zi̇ya Umul Jan 2009

General Formulation Of The Scattered Matter Waves By A Quantum Shutter, Yusuf Zi̇ya Umul

Turkish Journal of Physics

The scattering process of matter waves by a quantum shutter is investigated by using the spectrum integral representation. The scattered fields are expressed in terms of the Fresnel function. It is shown that the obtained equation gives the Moshinsky function for a one dimensional problem of the plane wave. Also a general integral representation is derived for two dimensional problems. The scattering of matter waves for some special wave-packets are examined analytically and numerically.