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Articles 6871 - 6900 of 10319
Full-Text Articles in Physical Sciences and Mathematics
Semiconducting Properties Of In_3te_4 Crystals: An Experimental Study, Gadelkarim Ata Gamal, Mohamed Ali Abouzied, Mohamud Fouad Sanaa
Semiconducting Properties Of In_3te_4 Crystals: An Experimental Study, Gadelkarim Ata Gamal, Mohamed Ali Abouzied, Mohamud Fouad Sanaa
Turkish Journal of Physics
IndiumTelluride In_3Te_4 crystal was characterized for electrical conductivity, Hall mobility, carrier concentration, and thermoelectric power (TEP) as a function of temperature in the range 202--526 K this was done with the aid of liquid nitrogen which enabled us to detect the intrinsic behavior. The crystals were prepared by a modified vertical Bridgman technique. Throughout these measurements various physical parameters, such as effective mass of charge carriers, carrier mobility, diffusion coefficient, and relaxation time for both majority and minority carriers were found.
Specific Heat Of Ytterbium Iron Garnet Yb_3fe_5o_{12} At Low Temperatures, Abdelmalek Boumali, Oumhani Derar
Specific Heat Of Ytterbium Iron Garnet Yb_3fe_5o_{12} At Low Temperatures, Abdelmalek Boumali, Oumhani Derar
Turkish Journal of Physics
The state of the Yb^{3+} ion of the ytterbium iron garnet (Yb_3Fe_5O_{12}) is suitable for the development of theoretical models with rather good approximations. Using the theory of two-level paramagnetic ions, the total and magnetic specific heat at low temperatures has been calculated. The influence of tensors g and G on the specific heat of YbIG has been examined. A comparison has been made of our results and those obtained with a model based on of the approximation of Weiss Molecular-Field (WMF) and experimental data.
Characterization Of Analog Modulation Of Algaas Lasers And The Induced Intensity Noise, Moustafa Ahmed, Nour Zaki El-Sayed, Hameeda Ibrahim, Kamal Abdelhady
Characterization Of Analog Modulation Of Algaas Lasers And The Induced Intensity Noise, Moustafa Ahmed, Nour Zaki El-Sayed, Hameeda Ibrahim, Kamal Abdelhady
Turkish Journal of Physics
The dynamics of AlGaAs laser diodes under analog intensity modulation are characterized and the associated intensity noise is evaluated. The study is based on numerical solution of the stochastic rate equations of semiconductor lasers. Based on the shape of the modulated laser signal, the modulation dynamics are classified into eight distinct types. Four types are characterized by continuous periodic signals, and three types have periodic pulsing signals. These signals happen to have period doubling or superposed by sub-peaks from the relaxation oscillations of the laser. The last type is chaos, in which the signal is irregular and non-uniform. The noise …
Monochromatization Effect Kinetic Model For Penning Gas Mixtures Emission Mechanisms, Catalina Ciobotaru, Geavit Musa
Monochromatization Effect Kinetic Model For Penning Gas Mixtures Emission Mechanisms, Catalina Ciobotaru, Geavit Musa
Turkish Journal of Physics
The monochromatization effect (M-effect), which consists in the reduction of an electronegative-electropositive gas mixtures discharge emission spectrum to only a few or a single line, was largely explained in our previous published papers together with their generation mechanisms, namely the polar ion-ion recombination and the energy resonance condition. This paper presents a kinetic model for the M-effect based on the radiative and collisional processes which appear between 1s_2, 1s_3, 1s_4 and 1s_5 Paschen levels, in Penning gas mixtures, where this effect was observed to be the most powerful.
The Differential Transform Method For Solving Heat-Like And Wave-Like Equations With Variable Coefficients, Khatereh Tabatabaei, Ercan Çeli̇k, Raziyeh Tabatabaei
The Differential Transform Method For Solving Heat-Like And Wave-Like Equations With Variable Coefficients, Khatereh Tabatabaei, Ercan Çeli̇k, Raziyeh Tabatabaei
Turkish Journal of Physics
In this article, Differential transform method is presented for solving heat-like and wave-like equations with variable coefficients. We applied these methods to six examples. This powerful method gives an exact solution. These examples are prepared to show the efficiency and simplicity of the method.
Resonant Electron Transfer And L-Shell Excitation For _{26}Fe^{19+} And _{30}Zn^{23+} Ions, Hassan Ramadan
Resonant Electron Transfer And L-Shell Excitation For _{26}Fe^{19+} And _{30}Zn^{23+} Ions, Hassan Ramadan
Turkish Journal of Physics
Resonant transfer and excitation (RTE) involving simultaneous electron capture and projectile L-shell excitation has been calculated for Fe^{19+} and Zn^{23+} ions, in charge states ranging from nitrogen-like to oxygen-like incident on molecular hydrogen over an energy range 0--250 MeV. By the same way the calculations have been performed with helium over an energy range 0--300 MeV. The calculations are carried out using the angular momentum average (AMA) scheme in the isolated resonance approximation (IRA). This method was previously used to calculate RTE cross sections for N-like P^{8+} and Ca^{13+}, where the results are found to agree with the present calculations. …
Nuclear Structure Of Xe-Pt Nuclei In The Framework Of Arm And Odd-Even Staggering, Harish Mohan Mittal, Vidya Devi
Nuclear Structure Of Xe-Pt Nuclei In The Framework Of Arm And Odd-Even Staggering, Harish Mohan Mittal, Vidya Devi
Turkish Journal of Physics
The asymmetric rotor model (ARM) of collective rotation is used to search for the correlation between the rotational energy with the asymmetric parameter \gamma_0 for Xe-Pt nuclei. The correspondence of the ratio ROTE/E(2_1^+) vs. R_{4/2}(=E(4_1^+)/E(2_1^+)) and \gamma_0 is used to distinguish between the axially symmetric and triaxial nuclei. The correlation between deformation parameter \beta and \gamma_0 is studied to understand the structure of the nuclei. The \gamma-band energy staggering in low-spin, low-energy spectra of even-even ^{122-124}Xe and ^{124-128}Ba nuclei is also discussed. We have compared our results with experimental data and other theoretical models.
The Impact Of Hyperfine Interaction On The Charge Radius Of Protons, Majid Amirfakhrian
The Impact Of Hyperfine Interaction On The Charge Radius Of Protons, Majid Amirfakhrian
Turkish Journal of Physics
In this paper, the wave function of a Proton has been calculated via solving the Dirac equation for a three-particle system. Then, the charge radius of the proton was measured. Isospin-Isospin interaction was added to the system as a perturbation factor, and the variation of the charge radius of Proton was considered. Finally, the spin-spin and spin-isospin interactions on the charge radius of the Proton were calculated based on this method.
Bianchi-V Cosmological Models With Viscous Fluid And Constant Deceleration Parameter In General Relativity, Sharad Kandalkar, Pramod Khade, Mohini Gaikwad
Bianchi-V Cosmological Models With Viscous Fluid And Constant Deceleration Parameter In General Relativity, Sharad Kandalkar, Pramod Khade, Mohini Gaikwad
Turkish Journal of Physics
In this paper we discuss the variation law for Hubble's parameter, average scale factor in spatially homogenous anisotropic Bianchi Type V space-time that yields a constant value deceleration parameter. Using the law of variation for Hubble's parameter, exact solutions of Einstein's field equations are obtained for Bianchi-V space time filled with viscous fluid in two different cases where the universe exhibits power law and exponential expansion. We investigate a number of solutions with constant and time varying cosmological constant together with variable and constant bulk viscosity. We find that the constant value of deceleration parameter is reasonable for the present …
Thermodynamics Of Liquid Alkali Metals Using Pseudopotential Perturbation Scheme, Jagendra Kamalsinh Baria, Ashvinkumar Ramaniklal Jani
Thermodynamics Of Liquid Alkali Metals Using Pseudopotential Perturbation Scheme, Jagendra Kamalsinh Baria, Ashvinkumar Ramaniklal Jani
Turkish Journal of Physics
Recently proposed model potential of Baria and Jani is used with the exchange and correlation effect of Sarkar et al. to calculate internal energy (Enthalpy), Entropy and Helmholtz free energy of liquid Na, K, Rb and Cs at various temperatures with the variational approach. The parameter of the potential is determined with the standard zero pressure condition. The structure factor derived by Percus-Yevick solution for hard sphere fluids which is characterized by hard sphere diameter \sigma is used. A good agreement between theoretical investigations and experimental findings has confirmed the ability of the model potential to the liquid alkali metals.
Te Surface Waves In Dielectric Slab Sandwiched Between Lhm Slabs, Ass'ad I. Ass'ad, Hassan S. Ashour
Te Surface Waves In Dielectric Slab Sandwiched Between Lhm Slabs, Ass'ad I. Ass'ad, Hassan S. Ashour
Turkish Journal of Physics
In this work, the dispersion relation for TE surface waves has been derived for a slab waveguide constructed from a dielectric material slab sandwiched between two thick layers of left-handed material (LHM). The dispersion relation and the power flow were numerically solved for a given set of parameters: the structural factor, dielectric slab thickness, and the operating frequency on the effective refractive index and power flow. We found that the wave effective refractive index decreases with thickness increase as well as increase in frequency. We found that the effective refractive index increases slightly with increase of structural factor. Also, the …
Prediction Of Some Mechanical And Vibrational Properties Of Gax (X = P, As, Sb) Semiconductor Compounds, Anil Ratilal Jivani, Ashvinkumar Ramniklal Jani
Prediction Of Some Mechanical And Vibrational Properties Of Gax (X = P, As, Sb) Semiconductor Compounds, Anil Ratilal Jivani, Ashvinkumar Ramniklal Jani
Turkish Journal of Physics
The static elastic constants (C_{11}, C_{12} and C_{44}), pressure derivative of elastic constants, pressure derivative of bulk modulus, propagation velocities of longitudinal and transverse waves in [100], [110] and [111] directions and Young modulus are investigated through computations using the higher-order perturbation theory based on pseudopotential formalism, in which we have applied our own proposed model potential for GaP, GaAs and GaSb semiconductor compounds. In the present calculations, two local-field correction functions are employed to consider exchange and correlation effects. The numerical values of the aforesaid properties are found to be sensitive to the selection of the local-field correction function …
Branching Of The W(H_4) Polytopes And Their Dual Polytopes Under The Coxeter Groups W(A_4) And W(H_3) Represented By Quaternions, Mehmet Koca, Nazi̇fe Koca, Mudhahir Al-Ajmi
Branching Of The W(H_4) Polytopes And Their Dual Polytopes Under The Coxeter Groups W(A_4) And W(H_3) Represented By Quaternions, Mehmet Koca, Nazi̇fe Koca, Mudhahir Al-Ajmi
Turkish Journal of Physics
4-dimensional H_4 polytopes and their dual polytopes have been constructed as the orbits of the Coxeter-Weyl group W(H_4), where the group elements and the vertices of the polytopes are represented by quaternions. Projection of an arbitrary W(H_4) orbit into three dimensions is made preserving the icosahedral subgroup W(H_3) and the tetrahedral subgroup W(A_3). The latter follows a branching under the Coxeter group W(A_4). The dual polytopes of the semi-regular and quasi-regular H_4 polytopes have been constructed.
Neutron Cross-Sections For ^{55}Mn In The Energy Range From 0.2 To 22 Mev, Abul Khaer Mohammad Rezaur Rahman
Neutron Cross-Sections For ^{55}Mn In The Energy Range From 0.2 To 22 Mev, Abul Khaer Mohammad Rezaur Rahman
Turkish Journal of Physics
Neutron total and differential elastic scattering cross-sections for ^{55}Mn nucleus was calculated from different global spherical optical potential (SOP) sets for different neutron energies ranging from 0.2 MeV to 22 MeV using the well known computer program SCAT-2 on an IBM PC-AT. In addition, the angular distributions of elastically scattered neutrons at different neutron energies were calculated. The results were compared with those of the experimental data obtained from the EXFOR data file of NEA data bank. The best-fit potential parameter was thereby selected. It was observed that the best fit to the experimental values of the total cross-sections are …
Admixture Of Higher Multi-\Hbar\Omega Configurations In The Calculation Of Electron Scattering Form Factors Of Some 1p-Shell Nuclei, Ammar A. Al-Sa'ad
Admixture Of Higher Multi-\Hbar\Omega Configurations In The Calculation Of Electron Scattering Form Factors Of Some 1p-Shell Nuclei, Ammar A. Al-Sa'ad
Turkish Journal of Physics
A semi-microscopic approach that modifies the 1p-shell model wave functions through the admixture of higher p-shells configurations from multi-\hbar\omega model space is submitted in this work. The longitudinal form factors of C2 transitions in ^7Li and ^{15}N, and the transverse form factors of M1 transition in ^{12}C are calculated in the framework of this approach with the emphasis on the reproduction of the second lobe data. It is found that a slight contribution of the higher multi-p-shells with the 1p-shell in the modified initial and/or final states wave functions is sufficient for giving the best description to the form factors …
Gamma Irradiation Effect On The Optical Properties And Refractive Index Dispersion Of Dye Doped Polystyrene Films, Tariq J. Alwan
Gamma Irradiation Effect On The Optical Properties And Refractive Index Dispersion Of Dye Doped Polystyrene Films, Tariq J. Alwan
Turkish Journal of Physics
In this work, we have studied the effect of the gamma irradiation on the optical properties and optical constants of Polystyrene doped by methylene blue (mb) with thickness in the range 0.11 + 5 mm. The samples have been investigated via transmittance and reflectance spectra, and characterized in the wavelength range 300-900 nm. The optical band gap E_g was determined while the optical absorption spectra showed that the absorption mechanism is an indirect allowed transition, which found that optical energy gap E_g decreases after irradiation. The optical constants (refractive index, extinction coefficient, and real and imaginary parts of the dielectric …
Hydrogen Implantation Effects On The Electrical And Optical Properties Of Inse Thin Films, Atef Fayez Qasrawi, Khaled Faisal Ilaiwi, Antonio Polimeni
Hydrogen Implantation Effects On The Electrical And Optical Properties Of Inse Thin Films, Atef Fayez Qasrawi, Khaled Faisal Ilaiwi, Antonio Polimeni
Turkish Journal of Physics
The effects of hydrogen ion implantation on the structural, electrical and optical properties of amorphous InSe thin films have been investigated. X-ray diffraction analysis revealed no change in the structure of the films. An implantation of 7.3 x 10^{18} ions/cm^2 decreased the electrical conductivity by three orders of magnitude at 300 K. Similarly, the conductivity activation energy, which was calculated in the temperature range of 300-420 K, decreased from 210 to 78 meV by H-ion implantation. The optical measurements showed that the direct allowed transitions energy band gap of amorphous InSe films has decreased from 1.50 to 0.97 eV by …
A Preliminary Study Of The Frequencies Infrared Spectrum Of The \Vartheta_4 Band Of Monoisotopic ^{34}Sf_6, Mohamed Meskine, Okkacha Ouardi, Abdelkrim Kaarour
A Preliminary Study Of The Frequencies Infrared Spectrum Of The \Vartheta_4 Band Of Monoisotopic ^{34}Sf_6, Mohamed Meskine, Okkacha Ouardi, Abdelkrim Kaarour
Turkish Journal of Physics
Octahedral formalism based on the notions of molecular symmetry is used in the calculation of the position lines of the \vartheta_4 band of ^{34}SF_6; we used an experimental spectrum near 650 cm^{-1}. This spectrum was analysed using XTDS and SPVIEW software's, developed in Dijon, France. We have 37 parameters to determined at the six order and for J_{max} = 95, using 1497 data. We have obtained an RMS = 0.598 x 10^{-3} cm^{-1}.
Electromagnetic Energy Conservation With Complex Octonions, Mustafa Emre Kansu, Murat Tanişli, Süleyman Demi̇r
Electromagnetic Energy Conservation With Complex Octonions, Mustafa Emre Kansu, Murat Tanişli, Süleyman Demi̇r
Turkish Journal of Physics
Octonions are the eight dimensional hypercomplex numbers that form a noncommutative and nonassociative division algebra. In this study, a general framework for the real, complex octonions and their algebra are provided by using the Cayley-Dickson multiplication rule between the octonionic basis elements. Maxwell's equations without sources are shown in Gauss units in dimensionless form. The local energy conservation equation, which has been previously defined in a complexified quaternionic form, is similarly rearranged for isotropic media by using the complex octonions. As a result, the terms of density and flow of electromagnetic energy are attained.
Heat And Mass Transfer In Hartmann Flow With Soret Effect In Presence Of A Constant Heat Source, Nazibuddin Ahmed
Heat And Mass Transfer In Hartmann Flow With Soret Effect In Presence Of A Constant Heat Source, Nazibuddin Ahmed
Turkish Journal of Physics
An exact solution of the laminar flow of an incompressible, viscous, electrically conducting fluid between two infinite, parallel, horizontal isothermal stationary walls in the presence of a transverse magnetic field and constant heat source, taking into account the induced magnetic field, induced electric field, Soret effect and dissipating heat is presented. The expressions for the non-dimensional velocity field, temperature field, concentration field, induced magnetic field, induced electric field, skin frictions at the walls and the co-efficients of the rates of heat and mass transfer at the walls in terms of the Nusselt and Sherwood numbers are obtained. The effects of …
Secrecy Logic: S-Secrecy Structures, George Voutsadakis
Secrecy Logic: S-Secrecy Structures, George Voutsadakis
Turkish Journal of Mathematics
Let S = \lan L,\vdash_S\ran be a deductive system. An S-secrecy logic is a quadruple K = \lan Fm_L(V),K,B,S\ran, where Fm_L(V) is the algebra of L-formulas, K,B are S-theories, with B \subseteq K and S \subseteq K such that S \cap B = \emptyset. K corresponds to information deducible from a knowledge base, B to information deducible from the publicly accessible (or browsable) part of the knowledge base and S is a secret set, a set of sensitive or private information that the knowledge base aims at concealing from its users. To provide models for this context, the notion of …
Weakly Normal Rings, Junchao Wei̇, Libin Li
Weakly Normal Rings, Junchao Wei̇, Libin Li
Turkish Journal of Mathematics
A ring R is defined to be weakly normal if for all a, r \in R and e \in E(R), ae = 0 implies Rera is a nil left ideal of R, where E(R) stands for the set of all idempotent elements of R. It is proved that R is weakly normal if and only if Rer(1-e) is a nil left ideal of R for each e \in E(R) and r \in R if and only if T_n(R, R) is weakly normal for any positive integer n. And it follows that for a weakly normal ring R (1) R is …
Best Simultaneous Approximation In Function And Operator Spaces, Eyad Abu-Sirhan
Best Simultaneous Approximation In Function And Operator Spaces, Eyad Abu-Sirhan
Turkish Journal of Mathematics
Let Z be a Banach space and G be a closed subspace of Z. For f_1,f_2 \in Z, the distance from f_1,f_2 to G is defined by d(f_1,f_2,G) = \underset{f \in G}{\inf} max { f_1-f , f_2-f }. An element g^{\ast} \in G satisfying max { f_1-g^{\ast } , f_2-g^{\ast } } = \underset{f \in G}{\inf } max { f_1-f , f_2-f } is called a best simultaneous approximation for f_1,f_2 from G. In this paper, we study the problem of best simultananeous approximation in the space of all continuous X-valued functions on a compact Hausdorff space S; C(S,X), and …
Invariant Parametrizations And Complete Systems Of Global Invariants Of Curves In The Pseudo-Euclidean Geometry, Ömer Pekşen, Djavvat Khadjiev, İdri̇s Ören
Invariant Parametrizations And Complete Systems Of Global Invariants Of Curves In The Pseudo-Euclidean Geometry, Ömer Pekşen, Djavvat Khadjiev, İdri̇s Ören
Turkish Journal of Mathematics
Let M(n, p) be the group of all transformations of an n-dimensional pseudo-Euclidean space E^n_p of index p generated by all pseudo-orthogonal transformations and parallel translations of E^n_p. Definitions of a pseudo-Euclidean type of a curve, an invariant parametrization of a curve and an M(n, p)-equivalence of curves are introduced. All possible invariant parametrizations of a curve with a fixed pseudo-Euclidean type are described. The problem of the M(n, p)-equivalence of curves is reduced to that of paths. Global conditions of the M(n, p)-equivalence of curves are given in terms of the pseudo-Euclidean type of a curve and the system …
Oscillation Of Third-Order Nonlinear Delay Difference Equations, Mustafa Fahri̇ Aktaş, Aydin Ti̇ryaki̇, Ağacik Zafer
Oscillation Of Third-Order Nonlinear Delay Difference Equations, Mustafa Fahri̇ Aktaş, Aydin Ti̇ryaki̇, Ağacik Zafer
Turkish Journal of Mathematics
Third-order nonlinear difference equations of the form \Delta (c_n\Delta (d_n\Delta x_n))+p_n\Delta x_{n+1}+q_nf(x_{n-\sigma})=0, n\geq n_{0} are considered. Here, {c_n}, {d_n}, {p_n}, and {q_n} are sequences of positive real numbers for n_0 \in N, f is a continuous function such that f(u) /u\geq K > 0 for u \neq 0. By means of a Riccati transformation technique we obtain some new oscillation criteria. Examples are given to illustrate the importance of the results.
On The Biharmonic Vector Fields, Mustapha Djaa, Hichem Elhendi, Seddik Ouakkas
On The Biharmonic Vector Fields, Mustapha Djaa, Hichem Elhendi, Seddik Ouakkas
Turkish Journal of Mathematics
The problem studied in this paper is related to the biharmonicity of a vector field from a Riemannian manifold (M,g) to its tangent bundle TM equipped with the Sasaki metric g^s. We show that a vector field on a compact manifold is biharmonic if and only if is harmonic. We also investigate the biharmonicity of vector field of M, as a map from (M,g) to (TM,g^s).
Structure Theory Of Central Simple Z_D-Graded Algebras, Cemal Koç, Yosum Kurtulmaz
Structure Theory Of Central Simple Z_D-Graded Algebras, Cemal Koç, Yosum Kurtulmaz
Turkish Journal of Mathematics
This paper investigates the structure theory of Z_d-central simple graded algebras and gives the complete decomposition into building block algebras. The results are also applied to generalized Clifford algebras, which are motivating examples of Z_d-central simple graded algebras.
A Homotopy For A Complex Of Free Lie Algebras, Michele Vergne
A Homotopy For A Complex Of Free Lie Algebras, Michele Vergne
Turkish Journal of Mathematics
Using the Guichardet construction, we compute the cohomology groups of a complex of free Lie algebras introduced by Alekseev and Torossian
An Oscillation Theorem For Second-Order Nonlinear Differential Equations Of Euler Type, Asadollah Aghajani, Vahid Roomi
An Oscillation Theorem For Second-Order Nonlinear Differential Equations Of Euler Type, Asadollah Aghajani, Vahid Roomi
Turkish Journal of Mathematics
We consider the nonlinear equation t^2x'' + g(x) = 0, where g(x) satisfies xg(x) > 0 for x \ne 0, but is not assumed to be sublinear or superlinear. We study the problem whether all nontrivial solutions of the equation are oscillatory in some critical cases.
Hilbert Functions And Betti Numbers Of Reverse Lexicographic Ideals In The Exterior Algebra, Marilena Crupi, Carmela Ferro'
Hilbert Functions And Betti Numbers Of Reverse Lexicographic Ideals In The Exterior Algebra, Marilena Crupi, Carmela Ferro'
Turkish Journal of Mathematics
Let K be a field, V a K-vector space with basis e_1,...,e_n and let E be the exterior algebra of V. We study the class of reverse lexicographic ideals in E. We analyze the behaviour of their Hilbert functions and Betti numbers.