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Full-Text Articles in Physical Sciences and Mathematics

Comparative Essential Oil Analysis Of Geranium Sylvaticum Extracted By Hydrodistillation And Microwave Distillation, Nuran Kahri̇man, Gonca Tosun, Hasan Genç, Nuretti̇n Yayli Jan 2010

Comparative Essential Oil Analysis Of Geranium Sylvaticum Extracted By Hydrodistillation And Microwave Distillation, Nuran Kahri̇man, Gonca Tosun, Hasan Genç, Nuretti̇n Yayli

Turkish Journal of Chemistry

The essential oil of Geranium sylvaticum L. (Geraniaceae) was isolated by hydrodistillation (HD) and microwave distillation (MD). The composition of the volatile oils was characterized by GC-FID and GC-MS. A total of 73 and 70 compounds were identified, constituting over 90.3% and 98.7% of oil composition of G. sylvaticum, respectively. Sesquiterpene hydrocarbons were shown to be the main group of constituents (HD: 31.7% and MD: 39.8%). The major component of the oils of G. sylvaticum was \gamma -muurolene (HD: 10.9% and MD: 19.6%). The comparative study showed that the amount of total volatiles (98.7%) and the major constituent (39.8%) were …


Quantum Chemical Studies On Tautomerism And Basicity Behavior Of Some 1,2,4-Triazole Derivatives, Cemi̇l Öğreti̇r, Yadi̇gar Gülseven Sidir, İsa Sidir, Erol Taşal Jan 2010

Quantum Chemical Studies On Tautomerism And Basicity Behavior Of Some 1,2,4-Triazole Derivatives, Cemi̇l Öğreti̇r, Yadi̇gar Gülseven Sidir, İsa Sidir, Erol Taşal

Turkish Journal of Chemistry

The acidity constants, relative stabilities, and tautomeric equilibrium constants of some 1,2,4-triazole derivatives were determined using the density functional theory (DFT) with the B3LYP method and 6-311G(d,p) basis set. The integral equation formalism version of the polarizable continuum model (IEFPCM) was used in the calculations of the aqueous phase. The calculated tautomeric equilibrium and relative stabilities values revealed that the 4H-1,2,4 triazole form for all studied molecules was favored over the 1H-1,2,4 triazole form. Protonation processes indicated the predominance of the 1H-1,2,4 triazole form over the 2H-1,2,4 triazole form. The correlation attempt between the experimental and the calculated acidity constants, …


Sublimation Of Graphite In Continuous And Pulsed Arc Discharges, Afshan Ashraf, Kashif Yaqub, Sumera Javeed, Sumaira Zeeshan, Rahila Khalid, Sohail Ahmad Janjua, Shoaib Ahmad Jan 2010

Sublimation Of Graphite In Continuous And Pulsed Arc Discharges, Afshan Ashraf, Kashif Yaqub, Sumera Javeed, Sumaira Zeeshan, Rahila Khalid, Sohail Ahmad Janjua, Shoaib Ahmad

Turkish Journal of Physics

Sublimation of graphite has been investigated in continuous and pulsed arc discharges. The results of continuous arc discharge between graphite electrodes are compared with pulsed arc discharge between cylindrical Aluminum cathode and annular graphite anode. The sublimed species include monoatomic and diatomic carbon clusters with their relative composition depending upon the mechanism of energy dissipation in graphite electrodes. Diatomic carbon (C_2) is the dominant subliming cluster. Emission spectroscopy of the Swan band system [d^3\prod _g -a^3\prod _u ] of C_2 has been used to investigate the thermodynamic state and to deduce the vibrational temperature (T_{vib}). The vibrational level densities indicate …


Role Of Quadrupole Deformation In Proton Emitting Nuclei In The Medium Mass Region, Chandrasekaran Anu Radha, Velayudham Ramasubramanian, Emmanuel James Jebaseelan Samuel Jan 2010

Role Of Quadrupole Deformation In Proton Emitting Nuclei In The Medium Mass Region, Chandrasekaran Anu Radha, Velayudham Ramasubramanian, Emmanuel James Jebaseelan Samuel

Turkish Journal of Physics

Nuclear structural studies at and beyond the proton drip line is done with the help of proton radioactivity. It is found that nuclei are not necessarily always spherical. The aim of the present work is to study the role of quadrupole deformation in proton rich nuclei, particularly with respect to odd Z nuclei within the region 50 < Z < 80 near the proton drip line. The deformation is studied using triaxially deformed cranked Nilsson Strutinsky method with tuning. Some of the nuclei in the medium mass region are found to be proton emitters from the ground state with appreciable deformation. Nuclei with 62 < Z < 67 shows considerable deformation that kindled the probability of instability within the nuclei. Significant ground state deformed shapes are observed in the 67 < Z < 73 region.


(E)-3-[(3-(Trifluoromethyl)Phenylimino)Methyl] Benzene-1,2-Diol: X-Ray And Dft Calculated Structures, Başak Koşar, Çi̇ğdem Albayrak, Mustafa Odabaşoğlu, Orhan Büyükgüngör Jan 2010

(E)-3-[(3-(Trifluoromethyl)Phenylimino)Methyl] Benzene-1,2-Diol: X-Ray And Dft Calculated Structures, Başak Koşar, Çi̇ğdem Albayrak, Mustafa Odabaşoğlu, Orhan Büyükgüngör

Turkish Journal of Chemistry

The crystal structure of (E)-3-[(3-(Trifluoromethyl)phenylimino)- methyl]benzene-1,2-diol was determined using X-ray diffraction and the molecular structure was investigated with density functional theory (DFT). The X-ray study showed that the title compound has a strong intramolecular O-H...N hydrogen bond and 3-dimensional crystal networks are primarily determined by O-H...O intermolecular hydrogen bonds and weak van der Waals interactions. The strong O-H...N bond is evidence of the preference for the phenol-imine tautomeric form in the solid state. Optimized molecular geometry was calculated with DFT at the B3LYP/6-31G(d,p) level. The results from both experiment and theoretical calculations for the title compound are compared with each …


The Linear Functionals On Fundamental Locally Multiplicative Topological Algebras, E. Ansari-Piri Jan 2010

The Linear Functionals On Fundamental Locally Multiplicative Topological Algebras, E. Ansari-Piri

Turkish Journal of Mathematics

In this paper we study the dual space of fundamental locally multiplicative topological algebras and prove some results for linear and multiplicative linear functionals on these algebras. An investigation on locally compactness of the carrier space of these algebras is the last part of this note.


State Variable Distributed-Parameter Representation Of Transmission Line For Transient Simulations, Mehmet Sali̇h Mami̇ş, Asim Kaygusuz, Muhammet Köksal Jan 2010

State Variable Distributed-Parameter Representation Of Transmission Line For Transient Simulations, Mehmet Sali̇h Mami̇ş, Asim Kaygusuz, Muhammet Köksal

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a distributed-parameter state variable approach is used to calculate transients on transmission lines based on the concept of travelling waves. The method of characteristics for lossless line is used and the state equations are derived for the system. These equations are converted to a set of difference equations using the trapezoidal rule of integration and solved in time domain using LU decomposition. Single- and multi-phase transmission lines with various linear and non-linear terminations are considered in the illustrative examples. State-space modeling of transposed lines using modal decomposition is introduced and the effects caused by lumped parameter approximation …


Artificial Neural Network Based Chaotic Generator For Cryptology, İlker Dalkiran, Kenan Danişman Jan 2010

Artificial Neural Network Based Chaotic Generator For Cryptology, İlker Dalkiran, Kenan Danişman

Turkish Journal of Electrical Engineering and Computer Sciences

Chaotic systems are sensitive to initial conditions, system parameters and topological transitivity and these properties are also remarkable for cryptanalysts. Noise like behavior of chaotic systems is the main reason of using these systems in cryptology. However some properties of chaotic systems such as synchronization, fewness of parameters etc. cause serious problems for cryptology. In this paper, to overcome disadvantages of chaotic systems, the dynamics of Chua's circuit namely x, y and z were modeled using Artificial Neural Network (ANN). ANNs have some distinctive capabilities like learning from experiences, generalizing from a few data and nonlinear relationship between inputs and …


Sufficient Conditions For Univalence Obtained By Using Second Order Linear Strong Differential Subordinations, Georgia Irina Oros Jan 2010

Sufficient Conditions For Univalence Obtained By Using Second Order Linear Strong Differential Subordinations, Georgia Irina Oros

Turkish Journal of Mathematics

The concept of differential subordination was introduced in [3] by S.S. Miller and P.T. Mocanu and the concept of strong differential subordination was introduced in [1], [2] by J.A. Antonino and S. Romaguera. In [5] we have studied the strong differential subordinations in the general case and in [6] we have studied the first order linear strong differential subordinations. In this paper we study the second order linear strong differential subordinations. Our results may be applied to deduce sufficient conditions for univalence in the unit disc, such as starlikeness, convexity, alpha-convexity, close-to-convexity respectively.


Uniqueness Of Derivatives Of Meromorphic Functions Sharing Two Or Three Sets, Abhijit Banerjee, Pranab Bhattacharjee Jan 2010

Uniqueness Of Derivatives Of Meromorphic Functions Sharing Two Or Three Sets, Abhijit Banerjee, Pranab Bhattacharjee

Turkish Journal of Mathematics

In the paper we consider the problem of uniqueness of derivatives of meromorphic functions when they share two or three sets and obtained five results which will improve all the existing results.


Nontrivial Periodic Solutions Of Nonlinear Functional Differential Systems With Feedback Control, Yingxin Guo Jan 2010

Nontrivial Periodic Solutions Of Nonlinear Functional Differential Systems With Feedback Control, Yingxin Guo

Turkish Journal of Mathematics

This paper examines the existence of nontrivial periodic solutions for the nonlinear functional differential system with feedback control: \{\aligned x'(t)=x(t)a(t)-\big[\sum_{i=1}^n a_i(t)\int_0^{+\infty} f(t, x(t-\theta)) d}\varphi_i(\theta) +\sum_{j=1}^m b_j(t) \int_0^{+\infty} f(t,x'(t-\theta))\,d}\phi_j(\theta)+\sum_{\mu=1}^p c_\mu(t) \int_0^{\infty} u(t-\theta)\,d}\delta_\mu(\theta)\big], u'(t)=-\rho(t)u(t)+\sum_{\nu=1}^q \beta_\nu(t) \int_0^{\infty} f(t, x(t-\theta))\,d}\psi_\nu(\theta).\endaligned Under certain growth conditions on the nonlinearity f, several sufficient conditions for the existence of nontrivial solution are obtained by using Leray-Schauder nonlinear alternative.


A Note On Dominant Contractions Of Jordan Algebras, Farrukh Mukhamedov, Seyi̇t Temi̇r, Hasan Akin Jan 2010

A Note On Dominant Contractions Of Jordan Algebras, Farrukh Mukhamedov, Seyi̇t Temi̇r, Hasan Akin

Turkish Journal of Mathematics

We consider two positive contractions T,S:L_1(A,\tau) \longrightarrow L_1(A,\tau) such that T\leq S, here (A, \tau) is a semi-finite JBW-algebra. If there is an n_0 \in N such that S^{n_0}-T^{n_0}


The Equivalence Of Centro-Equiaffine Curves, Yasemi̇n Sağiroğlu, Ömer Pekşen Jan 2010

The Equivalence Of Centro-Equiaffine Curves, Yasemi̇n Sağiroğlu, Ömer Pekşen

Turkish Journal of Mathematics

The motivation of this paper is to find formulation of the SL(n,R)-equivalence of curves. The types for centro-equiaffine curves and for every type all invariant parametrizations for such curves are introduced. The problem of SL(n,R)-equivalence of centro-equiaffine curves is reduced to that of paths. The centro-equiaffine curvatures of path as a generating system of the differential ring of SL(n,R)-invariant differential polinomial functions of path are found. Global conditions of SL(n,R)-equivalence of curves are given in terms of the types and invariants. It is proved that the invariants are independent.


B.-Y. Chen Inequalities For Slant Submanifolds In Quaternionic Space Forms, Gabriel Eduard Vilcu Jan 2010

B.-Y. Chen Inequalities For Slant Submanifolds In Quaternionic Space Forms, Gabriel Eduard Vilcu

Turkish Journal of Mathematics

In this paper some B.-Y. Chen inequalities for slant submanifolds in quaternionic space forms are established.


New Inequalities Similar To Hardy-Hilbert's Inequality, Namita Das, Srinibas Sahoo Jan 2010

New Inequalities Similar To Hardy-Hilbert's Inequality, Namita Das, Srinibas Sahoo

Turkish Journal of Mathematics

In this paper, we establish a new inequality similar to Hardy-Hilbert's inequality. As applications, some particular results and the equivalent form are derived. The integral analogues of the main results are also given.


Trace Formulae For Schrödinger Systems On Graphs, Chuan-Fu Yang, Zhen-You Huang, Xiao-Ping Yang Jan 2010

Trace Formulae For Schrödinger Systems On Graphs, Chuan-Fu Yang, Zhen-You Huang, Xiao-Ping Yang

Turkish Journal of Mathematics

For Schrödinger systems on metric graphs with \delta'-type conditions at the central vertex, firstly, we obtain precise description for the square root of the large eigenvalue up to the o(1/n)-term. Secondly, the regularized trace formulae for Schrödinger systems are calculated with some techniques in classical analysis. Finally, these formulae are used to obtain a result of inverse problem in the spirit of Ambarzumyan.


Structural Properties Of Bilateral Grand Lebesque Spaces, E. Liflyand, E. Ostrovsky, L. Sirota Jan 2010

Structural Properties Of Bilateral Grand Lebesque Spaces, E. Liflyand, E. Ostrovsky, L. Sirota

Turkish Journal of Mathematics

In this paper we study the multiplicative, tensor, Sobolev and convolution inequalities in certain Banach spaces, the so-called Bilateral Grand Lebesque Spaces. We also give examples to show the sharpness of these inequalities when possible.


On Harmonicity In Some Moufang-Klingenberg Planes, Basri̇ Çeli̇k, Ati̇lla Akpinar, Süleyman Çi̇ftçi̇ Jan 2010

On Harmonicity In Some Moufang-Klingenberg Planes, Basri̇ Çeli̇k, Ati̇lla Akpinar, Süleyman Çi̇ftçi̇

Turkish Journal of Mathematics

In this paper we study Moufang-Klingenberg planes M (A) defined over a local alternative ring A of dual numbers. We show that some collineations of M (A) preserve cross-ratio and thus establish a relation between harmonicity and harmonic position.


Characterizations Of Slant Helices In Euclidean 3-Space, Levent Kula, Nejat Ekmekci̇, Yusuf Yayli, Kazim İlarslan Jan 2010

Characterizations Of Slant Helices In Euclidean 3-Space, Levent Kula, Nejat Ekmekci̇, Yusuf Yayli, Kazim İlarslan

Turkish Journal of Mathematics

In this paper we investigate the relations between a general helix and a slant helix. Moreover, we obtain some differential equations which they are characterizations for a space curve to be a slant helix. Also, we obtain the slant helix equations and its Frenet aparatus.


On Purely Real Surfaces In Kaehler Surfaces, Bang-Yen Chen Jan 2010

On Purely Real Surfaces In Kaehler Surfaces, Bang-Yen Chen

Turkish Journal of Mathematics

An immersion \phi colon M to \tilde M^2 of a surface M into a Kaehler surface is called purely real if the complex structure J on \tilde M^2 carries the tangent bundle of M into a transversal bundle. In the first part of this article, we prove that the equation of Ricci is a consequence of the equations of Gauss and Codazzi for purely real surfaces in any Kaehler surface. In the second part, we obtain a necessary condition for a purely real surface in a complex space form to be minimal. Several applications of this condition are provided. In …


When \Delta-Semiperfect Rings Are Semiperfect, Engi̇n Büyükaşik, Christian Lomp Jan 2010

When \Delta-Semiperfect Rings Are Semiperfect, Engi̇n Büyükaşik, Christian Lomp

Turkish Journal of Mathematics

Zhou defined \delta-semiperfect rings as a proper generalization of semiperfect rings. The purpose of this paper is to discuss relative notions of supplemented modules and to show that the semiperfect rings are precisely the semilocal rings which are \delta-supplemented. Module theoretic version of our results are obtained.


Some Sufficient Conditions For Starlikeness And Convexity, Mamoru Nunokawa, Shigeyoshi Owa, Yaşar Polatoğlu, Mert Çağlar, Emel Yavuz Duman Jan 2010

Some Sufficient Conditions For Starlikeness And Convexity, Mamoru Nunokawa, Shigeyoshi Owa, Yaşar Polatoğlu, Mert Çağlar, Emel Yavuz Duman

Turkish Journal of Mathematics

There are many results for sufficient conditions of functions f(z) which are analytic in the open unit disc U to be starlike and convex in U. In view of the results due to S. Ozaki, I. Ono and T. Umezawa (1956), P.T. Mocanu (1988), and M. Nunokawa (1993), some sufficient conditions for starlikeness and convexity of f(z) are discussed.


Injective Simplicial Maps Of The Arc Complex, Elmas Irmak, John D. Mccarthy Jan 2010

Injective Simplicial Maps Of The Arc Complex, Elmas Irmak, John D. Mccarthy

Turkish Journal of Mathematics

In this paper, we prove that each injective simplicial map of the arc complex of a compact, connected, orientable surface with nonempty boundary is induced by a homeomorphism of the surface. We deduce, from this result, that the group of automorphisms of the arc complex is naturally isomorphic to the extended mapping class group of the surface, provided the surface is not a disc, an annulus, a pair of pants, or a torus with one hole. We also show, for each of these special exceptions, that the group of automorphisms of the arc complex is naturally isomorphic to the quotient …


An Expansion Result For A Sturm-Liouville Eigenvalue Problem With Impulse, Şeri̇fe Faydaoğlu, Gusein Sh. Guseinov Jan 2010

An Expansion Result For A Sturm-Liouville Eigenvalue Problem With Impulse, Şeri̇fe Faydaoğlu, Gusein Sh. Guseinov

Turkish Journal of Mathematics

The paper is concerned with an eigenvalue problem for second order differential equations with impulse. Such a problem arises when the method of separation of variables applies to the heat conduction equation for two-layered composite. The existence of a countably infinite set of eigenvalues and eigenfunctions is proved and a uniformly convergent expansion formula in the eigenfunctions is established.


Notes On Null Curves In Minkowski Spaces, Makoto Sakaki Jan 2010

Notes On Null Curves In Minkowski Spaces, Makoto Sakaki

Turkish Journal of Mathematics

We show a correspondence between the evolute of a null curve and the involute of a certain spacelike curve in the 4-dimensional Minkowski space. Also we characterize pseudo-spherical null curves in the n-dimensional Minkowski space in terms of the curvature functions.


A Short Survey On Mathematical Work Of Cemal Koç, İsmai̇l Şuayi̇p Güloğlu Jan 2010

A Short Survey On Mathematical Work Of Cemal Koç, İsmai̇l Şuayi̇p Güloğlu

Turkish Journal of Mathematics

No abstract provided.


On Abelian Rings, Nazim Agayev, Abdullah Harmanci, Sai̇t Halicioğlu Jan 2010

On Abelian Rings, Nazim Agayev, Abdullah Harmanci, Sai̇t Halicioğlu

Turkish Journal of Mathematics

Let \alpha be an endomorphism of an arbitrary ring R with identity. In this note, we introduce the notion of \alpha-abelian rings which generalizes abelian rings. We prove that \alpha-reduced rings, \alpha-symmetric rings, \alpha-semicommutative rings and \alpha-Armendariz rings are \alpha-abelian. For a right principally projective ring R, we also prove that R is \alpha-reduced if and only if R is \alpha-symmetric if and only if R is \alpha-semicommutative if and only if R is \alpha-Armendariz if and only if R is \alpha-Armendariz of power series type if and only if R is \alpha-abelian.


On Weakly M-Supplemented Primary Subgroups Of Finite Groups, Long Miao, Wolfgang Lempken Jan 2010

On Weakly M-Supplemented Primary Subgroups Of Finite Groups, Long Miao, Wolfgang Lempken

Turkish Journal of Mathematics

A subgroup H of a group G is said to be weakly M-supplemented in G if there exists a subgroup B of G provided that (1) G=HB, and (2) if H_1/H_G is a maximal subgroup of H/H_G, then H_1B=BH_1


Statistical Convergence Of Max-Product Approximating Operators, Oktay Duman Jan 2010

Statistical Convergence Of Max-Product Approximating Operators, Oktay Duman

Turkish Journal of Mathematics

In this study, using the notion of statistical convergence, we obtain various statistical approximation theorems for a general sequence of max-product approximating operators, including Shepard type operators, although its classical limit fails. We also compute the corresponding statistical rates of the approximation.


On Construction Of Coherent States Associated With Homogeneous Spaces, Ali Akbar Arefijamaal Jan 2010

On Construction Of Coherent States Associated With Homogeneous Spaces, Ali Akbar Arefijamaal

Turkish Journal of Mathematics

In this article, assume that G=H\times_{\tau} K is the semidirect product of two locally compact groups H and K, respectively and consider the quasi regular representation on G. Then for some closed subgroups of G we investigate an admissible condition to generate the Gilmore-Perelomov coherent states. The construction yields a wide variety of coherent states, labelled by a homogeneous space of G.