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Articles 9871 - 9900 of 10317
Full-Text Articles in Physical Sciences and Mathematics
Elastic Scattering Of 344.5 Mev ^{12}C Ions From ^{11}B Nucleus, S.A.E. Khallaf, M.A. Abdel-Rahman, S.K. Abdel-Rahman, S.W.Z. Mahmoud
Elastic Scattering Of 344.5 Mev ^{12}C Ions From ^{11}B Nucleus, S.A.E. Khallaf, M.A. Abdel-Rahman, S.K. Abdel-Rahman, S.W.Z. Mahmoud
Turkish Journal of Physics
The angular distribution of the elastic scattering differential cross section of 344.5 MeV $^{12}$C ions from $^{11}$B nucleus is calculated and compared with the experimental data as well as the previously published calculations. The real part of the central optical potential is derived using the double-folding and single-folding procedures assuming Gaussian forms of the nucleon-nucleon and alpha-nucleon interactions, respectively. A nuclear matter density distribution function of $^{11}$B consisting of a spherical part plus a quadrupole term is used. The inclusion of the quadrupole term is found necessary to obtain good fits to the experimental data.
Space Charge Limited Current In Films Obtained In Glow Discharge Plasma, M.M. Akhmedov, M.K. Kerimov, B.A. Suleimanov, S.A. Mansimov
Space Charge Limited Current In Films Obtained In Glow Discharge Plasma, M.M. Akhmedov, M.K. Kerimov, B.A. Suleimanov, S.A. Mansimov
Turkish Journal of Physics
The electrical current in thin films obtained by the polymerization of acetonitrile in glow discharge on a heated substrate were investigated in order to determine the mechanism of electrical conduction. The results of the field dependence, sample thickness dependence of the dark conductivity, supported by the results of photocurrent measurements, suggest an exponential energy distribution of traps inside the band gap of the polymer.
Cahit Arf's Contribution To Algebraic Number Theory And Related Fields, Masatoshi G. İkeda
Cahit Arf's Contribution To Algebraic Number Theory And Related Fields, Masatoshi G. İkeda
Turkish Journal of Mathematics
No abstract provided.
Timelike Ruled Surfaces In The Minkowski 3-Space-Ii, A. Turgut, H. H. Hacisali̇oğlu
Timelike Ruled Surfaces In The Minkowski 3-Space-Ii, A. Turgut, H. H. Hacisali̇oğlu
Turkish Journal of Mathematics
This paper is devoted to a study of timelike ruled surfaces in three dimensional Minkowski space obtained by a spacelike straight line moving along a timelike curve. The central point, the curve of striction and the distribution parameter of a timelike ruled surface in Minkowski 3-space are considered, and some theorems relating to their structure are obtained. In addition, some results about developable timelike ruled surfaces are also given.
A Berry-Esseen Bound For Empty Boxes Statistic On The Scheme An Allocations Of Several Type Balls, S.A. Mirakhmedov, O. Saidova
A Berry-Esseen Bound For Empty Boxes Statistic On The Scheme An Allocations Of Several Type Balls, S.A. Mirakhmedov, O. Saidova
Turkish Journal of Mathematics
A Berry-Esseen bound for the number of empty cells in the scheme of independent and random allocation of balls of $s$ type into different cells is obtained.
Weighted Ergodic Averages, M.D. Ha
Weighted Ergodic Averages, M.D. Ha
Turkish Journal of Mathematics
Let $(X, {\cal F}, \lambda)$ be the unit circle $\Bbb S^1 = \{z \in \Bbb C : z = 1\}$ with the usual $\sigma$-algebra ${\cal F}$ of Lebesgue measurable subsets and the normalized Lebesgue measure $\lambda$. Consider a sequence $\nu_n: \Bbb N \ra \Bbb R, \;\; \nu_n(k) \geq 0, \;\; \Sigma^{\infty}_{k=1} \nu_n(k) = 1$. For any measure-preserving $\tau : X \ra X$, this sequence induces a sequence $(T_n)^{\infty}_1$ of bounded, linear operators on $L^p(X), \;\; 1 \leq p \leq \infty$, by defining \[ T_n f = \sum^{\infty}_{k=1} \nu_n(k) \; f \circ \tau^k, \quad n = 1, 2, \ldots . \] …
Generalized Inverse Estimator And Comparison With Least Squares Estimator, S. Sakallıoğlu, F. Akdeniz
Generalized Inverse Estimator And Comparison With Least Squares Estimator, S. Sakallıoğlu, F. Akdeniz
Turkish Journal of Mathematics
Trenkler [13] described an iteration estimator. This estimator is defined as follows: for $0 < \gamma < 1/\lambda_i \max$ \[ \hat{\beta}_{m, \gamma} = \gamma \sum^m_{i=0} (1-\gamma X'X)^i X'y , \] where $\lambda_i$ are eigenvalues of $X'X$. In this paper a new estimator (generalized inverse estimator) is introduced based on the results of Tewarson [11]. A sufficient condition for the difference of mean square error matrices of least squares estimator and generalized inverse estimator to be positive definite (p.d.) is derived.
Direct Sums And The Schur Property, Betül Tanbay
Direct Sums And The Schur Property, Betül Tanbay
Turkish Journal of Mathematics
It is a known fact that $\ell^1$, the dual space of the null sequences $c_0$, has the Schur property, that is, weakly convergent sequences in $\ell^1$ are norm convergent. In this paper, we prove that if $(X_{\alpha})_{\alpha\in I}$ are Banach spaces and $X=(\oplus_{\alpha\in I}X_{\alpha})_1$ their $l_1$-sum, then the space $X$ has the Schur property iff each factor $X_{\alpha}$ has it.
Xps Investigations On Conducting Polymers, Ş. Süzer, Ö. Bi̇rer, U.A. Sevi̇l, O. Güven
Xps Investigations On Conducting Polymers, Ş. Süzer, Ö. Bi̇rer, U.A. Sevi̇l, O. Güven
Turkish Journal of Chemistry
X-ray photoelectron spectroscopy, XPS, was used for the characterization of electrically conducting polymeric materials. In the spectrum of polypyrrole, PPy, the Nls region exhibits two peaks, at 402.0 and 399.8 eV, corresponding to -N$^+$- and -N- moieties, respectively. The intensity of the N$^+$ peak decreases as the material loses its conductivity, hence the ratio of the experimentally derived N$^+$/C atomic ratio correlates exponentially with the measured conductivity. A similar observation also exists between the F$^-$/C atomic ratio both in polypyrrole and polythiophene. In the XPS spectrum of the composite material prepared using polyaniline, PAN and polyvinylchloride, PVC, two different kinds …
Commingling Of Contrasted Magmas In Various Geodynamic Settings, Bernard Plateovet, Jean Bebien, Edilene Gomes
Commingling Of Contrasted Magmas In Various Geodynamic Settings, Bernard Plateovet, Jean Bebien, Edilene Gomes
Turkish Journal of Earth Sciences
Three acid-basic associations taken in various geodynamical settings are studied: the gabbro-granite association of Porto (Corsica), the associations of the Guevgueli (Greek Macedonia), and the associations of the Piracaia complex (Brazil). The diversity of field relations, the degree of mingling, the origins of the melts are debated for each association, using petrological and geochemical tools for each acid-basic association. An origin by hybridization is assumed for the intermediate rocks of the Porto association, it is tested by numerical calculation. Then, we focus on the mixing process between the comagmatic components. Mixing of melts may have happened by thorough mingling and …
Geochemical And Petrological Characteristics Of The Eastern Pontide Eocene (?) Alkaline Volcanic Province, Ne Turkey, Cüneyt Şen, Mehmet Arslan, Ali̇ Van
Geochemical And Petrological Characteristics Of The Eastern Pontide Eocene (?) Alkaline Volcanic Province, Ne Turkey, Cüneyt Şen, Mehmet Arslan, Ali̇ Van
Turkish Journal of Earth Sciences
The Eastern Pontide Alkaline Volcanic Province is developed by volcanic cycles erupted in Cenozoic era. Petrographical and geochemical data suggest presence of at least two different suits of alkaline rocks (Tonya group and Trabzon group). Petrographically, both groups consist of alkali basalt, tephrite, phonolitic tephrite, basanite, nephelinite, nepheline latite and their pyroclastic rocks. Geochemically, Tonya samples have high MgO and Ni, low LREE contents and LILE/HFSE ratios compare to Trabzon group. Preliminary studies show that these two groups of rocks are related with low level differentiation and derived from a metasomatised mantle source.
Finite Direct Sums Of (D1)-Modules, Derya Keskin
Finite Direct Sums Of (D1)-Modules, Derya Keskin
Turkish Journal of Mathematics
In this paper we give necessary conditions for a finite direct sum of (D1)--modules to be a (D1)--module.
Derivation Of Separable Amplitude Equations By Multiple Scales Method, Mehmet Naci̇ Özer, Dursun Eser
Derivation Of Separable Amplitude Equations By Multiple Scales Method, Mehmet Naci̇ Özer, Dursun Eser
Turkish Journal of Mathematics
The method of multiple scales is used to derive separable nonlinear Schrödinger equations as amplitude equation from three component 2D nonlinear Klein-Gordon Equation. We further discuss the integrability of the derived separable amplitude equations and reduce them into finite dimensional Hamiltonian systems. Finally we give first integrals for the reduced systems.
Cess-Modules, Cesim Çelik
Cess-Modules, Cesim Çelik
Turkish Journal of Mathematics
In this paper, we investigate generalizations of CS-modules, namely CESS-modules, weak CS-modules and modules satisfying a condition (P). Several results are given to show the relationships between the classes of these modules.
About Some Classical Functional Equations, Nicolae Neamtu
About Some Classical Functional Equations, Nicolae Neamtu
Turkish Journal of Mathematics
The purpose of this paper is to give a new method of finding the solution of Lobashevsky's functional equation and those of other classical functional equations. At the beginning we present the properties of solution $f, \; f \neq 0$, of Lobachevsky's functional equation. Using only the boundedness property on $(-r, r)$, we deduce the continuity, convexity and differentiability properties of the solution.
Use Of The Magnetic Field Generated By The Internal Distribution Of Injected Currents For Electrical Impedance Tomography (Mr-Eit), Y. Zi̇ya İder, Özlem Bi̇rgül
Use Of The Magnetic Field Generated By The Internal Distribution Of Injected Currents For Electrical Impedance Tomography (Mr-Eit), Y. Zi̇ya İder, Özlem Bi̇rgül
Turkish Journal of Electrical Engineering and Computer Sciences
In two dimensional conventional Electrical Impedance Tomography (EIT), volume conductor is probed by means of injected currents, and peripheral voltage measurements are used as input to the reconstruction algorithm. The current that flows in the 2D object creates magnetic fields that are perpendicular to the plane of imaging. Such magnetic fields can be measured using magnetic resonance tomography. In this study, use of this magnetic field generated by the injected currents, for the purpose of reconstructing the conductivity distribution, is studied. Sensitivity matrix relating the magnetic field to the element conductivities is calculated using the Finite Element Method and Biot-Savart …
The Relation Between Dislocation Density And Crystal Crosscut In \Beta-Sn Grown By Modified Bridgman Method, Bahattin Düzgün, İbrahim Karaman, Nazım Uçar
The Relation Between Dislocation Density And Crystal Crosscut In \Beta-Sn Grown By Modified Bridgman Method, Bahattin Düzgün, İbrahim Karaman, Nazım Uçar
Turkish Journal of Physics
Crystals $\beta$-Sn are grown from ingots of 99.99\% purity by modified Bridgman method under $10^{-3}$ torr pressure and oriented by Laue back reflection method. The relation between crystal crosscut and dislocation density calculated using etch hillock technique is investigated. It is found that the dislocation density increases with increasing crystal crosscut.
Study Of Magnetic Non-Uniformities In Yttrium-Iron Garnet By The Measuring Method Of Magneto-Optical Susceptibility, Komil Mukimov, Odil Ochilov, Makhset Khalmuratov, Asror Ramazanov, Ulpash Mirzakulova
Study Of Magnetic Non-Uniformities In Yttrium-Iron Garnet By The Measuring Method Of Magneto-Optical Susceptibility, Komil Mukimov, Odil Ochilov, Makhset Khalmuratov, Asror Ramazanov, Ulpash Mirzakulova
Turkish Journal of Physics
Study of magnetic non-uniformities in yttrium-iron garnet by the measuring in method of magneto-optical susceptibility in laser beam with the wave length of \lambda = 1.15 \mu m.
Infrared Absorption Study Of Potassium-Boro-Vanadate-Iron Glasses, Dinesh K. Kanchan, Harshvadan R. Panchal
Infrared Absorption Study Of Potassium-Boro-Vanadate-Iron Glasses, Dinesh K. Kanchan, Harshvadan R. Panchal
Turkish Journal of Physics
The IR studies have been made in the K_2O-B_2O_3-V_2O_5-Fe_2O_3 glass system. The increase in intensity and shifting of vibrational bands towards lower wave number at 1400-1350 cm^{-1}, 1200 cm^{-1} and 100-940 cm^{-1} in IR spectra have been ascribed to the formation of BO_3 to BO_4 and VO_5 to VO_4 tetrahedra along with the formation of non-bridging oxygens attached to boron and vanadium. In heat-treated glass samples, many new vibrational bands have been observed which were however, absent in the untreated samples. The preservation of the 1020 cm^{-1} band assigned to V=O bond suggests that K_2O shows the preference for borate …
Bulk Modulus Calculations Of Liquid Alkali Metal Alloys, Mehmet Yilmaz, Seyfeddin Karagözoğlu, İris Gümüş
Bulk Modulus Calculations Of Liquid Alkali Metal Alloys, Mehmet Yilmaz, Seyfeddin Karagözoğlu, İris Gümüş
Turkish Journal of Physics
In this work, the bulk modulus values for liquid alkali metal alloys near melting point are studied in the framework of the Gibbs-Bogoliubov method. We use the local Heine-Abarenkov pseudopotential and Ichimaru-Utsumi screening function in these alloys. The results are compared with experimental and theoretical results.
High-Power Diffusion Cooling Planar Waveguide Co_{2} Laser, E. Taal, M. S. Kiliçkaya
High-Power Diffusion Cooling Planar Waveguide Co_{2} Laser, E. Taal, M. S. Kiliçkaya
Turkish Journal of Physics
A diffusion-cooled CO_{2} laser using a coaxial waveguide is investigated theoretically. The resonator extracting the laser beam consits of two annular plane mirrors enclosing the two ends of the waveguide. A theoretical resonator model based on the vector modes of propagation in a dielectric coaxial waveguide is described.
A Phase Diagram Of The Nematic, Smectic A And Smectic C Phases In Liquid Crystals, S. Sali̇hoğlu, H. Yurtseven
A Phase Diagram Of The Nematic, Smectic A And Smectic C Phases In Liquid Crystals, S. Sali̇hoğlu, H. Yurtseven
Turkish Journal of Physics
In this study we have obtained a phase diagram for the nematic, smectic A and smectic C phases in liquid crystals. For this phase diagram we have studied two different mean field models for a mixture of liquid crystalline system. In our first model we consider the NC and AC transitions as first order, and the NA transition as a second order. In our second model we consider the NC and NA transitions as first order, and the AC transition as a second order.
Doping Effects Of Ga And Te On The Kinetic Coefficients Of Rhombohedral And Cubic Phases Of Ge_{1-X} Ga_X Te Solid Solution Alloys, T. Atalay, M.H. Akperov
Doping Effects Of Ga And Te On The Kinetic Coefficients Of Rhombohedral And Cubic Phases Of Ge_{1-X} Ga_X Te Solid Solution Alloys, T. Atalay, M.H. Akperov
Turkish Journal of Physics
In this study Ga and Te doping effects on the kinetic parameters (thermo e.m.f., electrical conductivity, heat conductivity, Hall and Nernst-Ettingshausen coefficients) of the rhombohedral and cubic phases of Ge_{1-x} Ga_x Te (0 < x \leq 0,06) solid solutions has been investigated between 77-900 K temperature intervals. Increase in the amount of Te increases hole concentration and reduces lattice constant, whereas rhombohedral propeties of GeTe rises with increase of Ga concentration. The observed anomalies on the kinetic parameters may be explained qualitatively by the complexity of the Fermi surface shape and the zone model of GeTe which involves the seperation of the L extremums that is same for ``\alpha'', ``\beta'' and ``\gamma'' phases of the compound.
Alkaline Rocks And Geodynamics, Bernard Bonin
Alkaline Rocks And Geodynamics, Bernard Bonin
Turkish Journal of Earth Sciences
Origin of A-type alkali feldspar granites is currently the subject of a world-wide debate. Contrasting hypotheses have been proposed, which range from an entirely crustal origin to an almost complete mantle derivation. A-type alkali feldspar granites belong to either unimodal granite (rhyolite)-dominated association, or bimodal gabbro (basalt)-granite (rhyolite) suite. It is argued that (i) the ultimate mantle origin of basic to intermediate rocks is beyond doubt, (ii) highly evolved felsic rocks may be produced by other processes besides crustal involvement through anatexis and (iii) large volumes of felsic rocks are a normal and direct consequence of extensive crystal fractionation processes. …
Normal Subgroups Of Hecke Groups On Sphere And, İsmai̇l Naci̇ Cangül, Osman Bi̇zi̇m
Normal Subgroups Of Hecke Groups On Sphere And, İsmai̇l Naci̇ Cangül, Osman Bi̇zi̇m
Turkish Journal of Mathematics
We use regular map theory to obtain all normal subgroups of Hecke groups of genus 0 and 1. The existence of a regular map corresponding uniquely to every normal subgroup of Hecke groups H(\lambda_q) is a result of Jones and Singerman, and it is frequently used here to obtain normal subgroups. It is found that when q is even, H(\lambda_q) has infinitely many normal subgroups on the sphere, while for odd q, this number is finite. The total number of normal subgroups of H(\lambda_q) on a torus is found to be either 0 or infinite. The latter case appears iff …
The Energy Spectra Of Gaas/Al_Xga_{1-X}As Quantum Dots, Mohammad El-Said, M. Abu Saa
The Energy Spectra Of Gaas/Al_Xga_{1-X}As Quantum Dots, Mohammad El-Said, M. Abu Saa
Turkish Journal of Physics
The energy expressions for QD presented in high- and low-magnetic fields are calculated. An interpolation formula between the energies of the quantum dot in both limits is proposed. The formula is implemented to produce the energy spectra of the parabolic quantum dot in the presence of a magnetic field of arbitrary strength. The transitions in the angular momenta of the ground state energy of interacting electrons confined in the quantum dot as a function of magnetic field strength is studied. A good agreement is obtained when our results are tested against exact numerical work.
Pullbacks Of Crossed Modules And Cat^1-Groups, Murat Alp
Pullbacks Of Crossed Modules And Cat^1-Groups, Murat Alp
Turkish Journal of Mathematics
In this paper, wer define the pullback cat$^{1}$-groups and we showed that the category of bullback cat$^{1}$-group is equivalent to the category of pullback crossed modules. 1991 A. M. S. C.: 13D99, 16A99, 17B99, 18D35.
Difference Method For A Singularly Perturbed Initial Value Problem, Gabi̇l Muhammadoğlu Amiraliyev
Difference Method For A Singularly Perturbed Initial Value Problem, Gabi̇l Muhammadoğlu Amiraliyev
Turkish Journal of Mathematics
In this paper we construct a completely exponentially fitted finite difference scheme for the initial value problem with small parameter by first and second derivatives. We prove the first order uniform convergence of the scheme in the sense of discrete maximum norm. Numerical results are presented.
Rotation In Stars, Halil Kirbiyik
Rotation In Stars, Halil Kirbiyik
Turkish Journal of Physics
In this study the subject of rotation in stars and its effects have been considered. First the historical development of the subject is reviewed. After discussing the observational aspects of rotation, the effect of rotation on evolution has been investigated. The velocity of rotational meridional circulation currents and related time scales were estimated. Mixing induced by circulation currents and the turbulence which may appear as a result of such a mixing have been studied. Order of magnitude calculations have shown that rotational mixing may occur in early type stars and thus contributes to the diffusion of chemical elements. Thus, it …
The Solutions Of The Classical Relativistic Two-Body Equation, Coşkun Önem
The Solutions Of The Classical Relativistic Two-Body Equation, Coşkun Önem
Turkish Journal of Physics
With the relativistic Kepler problem, a two-body system is studied for positronium, the hydrogen atom and $m_2 >> m_1$ cases.