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Full-Text Articles in Physical Sciences and Mathematics

Investigation Of The Influence Of Thiocarbamide In The Process Of Carbamide Deparaffinization, Sevi̇l Veli̇yeva Jan 2000

Investigation Of The Influence Of Thiocarbamide In The Process Of Carbamide Deparaffinization, Sevi̇l Veli̇yeva

Turkish Journal of Chemistry

The influence of thiocarbamide in the process of carbamide dewaxing was investigated. The dependence of separated paraffins on the quantity of thiocarbamide was examined experimentally. It was determined that the separation of paraffins becomes equal to zero when moles of carbamide and thiocarbamide in water-isopropyl alcohol solution are equal. The low-temperature qualities (the temperature of dimness and freezing) of dewaxed fuels were also examined. By using infrared spectroscopy methods, the compound of received paraffins was investigated.


Information And Average Information Rates Of A Graphical Access Structure On Six Vertices, Mustafa Atici Jan 2000

Information And Average Information Rates Of A Graphical Access Structure On Six Vertices, Mustafa Atici

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper we study the optimal information and average information rates of secret sharing schemes which are all connected graphs on six vertices. There are $102$ connected graphs on six vertices that are not complete multipartite graphs. Of these $102$ graphs, we determined the optimal information rate of $71$ graphs, and the optimal average information rate of $88$ graphs.


Borate Deposits Of Turkey And Argentina; A Summary And Geological Comparison, Cahi̇t Helvaci, Ricardo R. Alonso Jan 2000

Borate Deposits Of Turkey And Argentina; A Summary And Geological Comparison, Cahi̇t Helvaci, Ricardo R. Alonso

Turkish Journal of Earth Sciences

No abstract provided.


Solar Observations Made At The Malatya Station With Danjon Astrolabe, Orhan Gölbaşi, Hüseyi̇n Kiliç, Fernand Chollet Jan 2000

Solar Observations Made At The Malatya Station With Danjon Astrolabe, Orhan Gölbaşi, Hüseyi̇n Kiliç, Fernand Chollet

Turkish Journal of Physics

The first results of astrometric solar observations made at the Malatya Station with a modified version of the Paris Observatory astrolabe are presented. This campaign was conducted as part of a cooperation between Inonü University and the Paris Observatory. The astrolabe, exactly the same as the one at Santiago de Chile [1], uses two reflecting prisms instead of transparent prisms in order to be able to observe at two zenith distances of 30^o and 60^o. The time is supplied by a Global Positioning System (GPS) receiver. The measurements (Table 1, 2) made between 1993 and 1994, were used in obtaining …


The Effect Of Iterative Solutions In The Quasi-Adiabatic Treatment Of Transfer Reactions Involving Deuterons, Mustafa Yilmaz, Bülent Gönül Jan 2000

The Effect Of Iterative Solutions In The Quasi-Adiabatic Treatment Of Transfer Reactions Involving Deuterons, Mustafa Yilmaz, Bülent Gönül

Turkish Journal of Physics

Using an iterative scheme, the effects of a more correct treatment of large n-p components of deuteron channel wavefunction in the continuum, which are associated with near-side contributions of transition amplitude, are investigated in the framework of the reformulated quasi-adiabatic model for the \( ^{116} \)Sn \( (d,p) \) \( ^{117} \)Sn reaction at 79 MeV bombarding energy. As the \( \ell_{n} \)-transfer rises, the far-side amplitude increases with improvements in the linear and angular momentum responce, which results in a relative suppression of the near-side components of the amplitude. Therefore, one might expect that the iteration of the quasi-adiabatic …


A Local-Pair Mechanism For High-Temperature Superconductivity At The Di- And Trivalent Sites, John A. Wilson, Ali̇ İhsan Demi̇rel Jan 2000

A Local-Pair Mechanism For High-Temperature Superconductivity At The Di- And Trivalent Sites, John A. Wilson, Ali̇ İhsan Demi̇rel

Turkish Journal of Physics

The \( p/d \) hybridization that primarily characterizes copper leads to local moments, lacking of the pair-breaking variety, both at di- and trivalent sites. Support for the negative-U model is extracted from the author's earlier work on the metal-insulator transition. A more magnetically oriented model, like the resonant valence band model which we have recently associated with our observations in d1 TiOCl etc., does not really seem suited to the geometry and electronic conditions in the copper oxides present. However it is suggested that TiB$_2$, La$_3$S$_4$ and the Chevrel phases might be open to treatment by such a model. Comment …


Switching Process In A Surface-Stabilized Ferroelectric Liquid Crystal Film, Ridvan Karapinar Jan 2000

Switching Process In A Surface-Stabilized Ferroelectric Liquid Crystal Film, Ridvan Karapinar

Turkish Journal of Physics

In this paper we first discuss the operating principle of a ferroelectric liquid crystal film in the surface stabilized configuration, and then examine the switching characteristics using optical measurements performed with a polarizing microscope.


The Canonical Thermodynamic Formalism: Chaotic States Of Spin And Gauge Systems, Nerses Ananikian Jan 2000

The Canonical Thermodynamic Formalism: Chaotic States Of Spin And Gauge Systems, Nerses Ananikian

Turkish Journal of Physics

The three-site antiferromagnetic Ising, $Q$-state Potts $(Q


From Antibracket To Equivariant Characteristic Classes, Armen Nersessian Jan 2000

From Antibracket To Equivariant Characteristic Classes, Armen Nersessian

Turkish Journal of Physics

We equip the exterior algebra of Riemann manifold by the odd symplectic structure. Then, by its use we construct the equivariant even (pre)symplectic structure, whose Poincare - Cartan invariants of the second structure define the equivariant Euler classes of the surfaces.


Canonical Quantisation Of The Sl(2,R)/ U(1) Gauged Wznw Black Hole Model, Christopher Ford, George Jorjadze, Gerhard Weigt Jan 2000

Canonical Quantisation Of The Sl(2,R)/ U(1) Gauged Wznw Black Hole Model, Christopher Ford, George Jorjadze, Gerhard Weigt

Turkish Journal of Physics

Gauged WZNW models are integrable conformal field theories with non-local canonical free-field transformations. Canonical quantisation requires quantum deformations.


The Statistics Of Energy States Of A Hookean Model For Proteins, Ayşe Erzan, Erkan Tüzel Jan 2000

The Statistics Of Energy States Of A Hookean Model For Proteins, Ayşe Erzan, Erkan Tüzel

Turkish Journal of Physics

A generic model of a random polypeptide chain, with discrete torsional degrees of freedom and Hookean springs connecting pairs of hydrophobic residues, reproduces the energy probability distribution of real proteins over a very large range of energies. We show that this system with harmonic interactions, under dissipative dynamics driven by random noise, leads to a distribution of energy states obeying a modified one-dimensional Ornstein-Uhlenbeck process with reflecting boundary conditions, and giving rise to distributions of the Wigner or inverse Gaussian form. A continuum approximation leads to a path integral formulation of the problem. PACS 5.65+b,5.70Ln,87.17.Aa


Cosmological Adiabatic Geometric Phase Of A Scalar Field In A Bianchi Spacetime, Ali̇ Mostafazadeh Jan 2000

Cosmological Adiabatic Geometric Phase Of A Scalar Field In A Bianchi Spacetime, Ali̇ Mostafazadeh

Turkish Journal of Physics

A two-component formulation of the Klein-Gordon equation is used to investigate the cyclic and noncyclic adiabatic geometric phases due to spatially homogeneous (Bianchi) cosmological models. It is shown that no adiabatic geometric phases arise for Bianchi type I models. For general Bianchi type IX models the problem of the adiabatic geometric phase is shown to be equivalent to the one for nuclear quadrupole interactions of a spin. For these models nontrivial non-Abelian adiabatic geometrical phases may occur in general.


The Effect Of Potassium Doping On Resistive Transitions And Transport Critical Current Of Bulk Ybco High-Tc Superconductors, S. Çelebi̇, A. Öztürk, İ. Karaca, U. Kölemen Jan 2000

The Effect Of Potassium Doping On Resistive Transitions And Transport Critical Current Of Bulk Ybco High-Tc Superconductors, S. Çelebi̇, A. Öztürk, İ. Karaca, U. Kölemen

Turkish Journal of Physics

We report on observations of the effect of potassium in YBCO (123) high temperature superconductors with nominal composition Y\( _{1-0,2x} \) Ba\( _{2-0.2x} \) K\( _{x} \) Cu\( _{3} \) O\( _{y} \). The electrical resistivity measurements show that the critical temperature T$_{c} \) (R=0) shifted slightly to lower temparature due to the K doping process. This process also decreases the transport critical current density and the activation energy for thermally activated flux flow. The magnetic field dependence of \( j_{c} \) was measured at 77 K after zero field cooling (ZFC) when the applied magnetic field is impressed (ZFCV) …


Optical Properties Of Zns Thin Films, M. Y. Nadeem, Waqas Ahmed Jan 2000

Optical Properties Of Zns Thin Films, M. Y. Nadeem, Waqas Ahmed

Turkish Journal of Physics

Zinc sulfide (ZnS) thin films of different thickness were deposited on Corning 7059 glass substrate at room temperature and high vacuum using resistive heating technique. The film properties investigated include their absorbance / transmittance / reflectance spectra, band gap, refractive index, extinction coefficient, optical conductivity, complex dielectric constant and thickness. The films were found to exhibit high transmittance (60-99\%), low absorbance and low reflectance in the visible / near infrared region up to 1100 nm. However, the absorbance of the films was found to be high in the ultra violet region with peak around 360 nm. The thickness (using quartz …


Determination Of Optical Constant Of Materials By Two Different Methods: An Application To Single Crystals Si, Hazi̇ret Durmuş, Haluk Şafak, Haldun Karabiyik Jan 2000

Determination Of Optical Constant Of Materials By Two Different Methods: An Application To Single Crystals Si, Hazi̇ret Durmuş, Haluk Şafak, Haldun Karabiyik

Turkish Journal of Physics

The normal reflectance of single crystal Si was measured at 0.5 ­5.6 eV range by unpolarized light. Optical parameters of Si were determined from this reflectance data by using two different methods: oscillator fit procedure and Kramers-Kronig analysis. The refractive index, extinction coefficient and the real and imaginary parts of complex dielectric constant obtained by these two methods were compared. A good agreement was found between two methods. Furthermore, the optical parameters so obtained seem to be in a satisfactory agreement with the literature.


On The Efficiency Of Finite Simple Semigroups, H. Ayik, C. M. Campbell, J. J. O'Connor, N. Ruskuc Jan 2000

On The Efficiency Of Finite Simple Semigroups, H. Ayik, C. M. Campbell, J. J. O'Connor, N. Ruskuc

Turkish Journal of Mathematics

Let $S$ be a finite simple semigroup, given as a Rees matrix semigroup $\mathcal{M}[G;I,\Lambda ;P]$ over a group $G$. We prove that the second homology of $S$ is $H_{2}(S)=H_{2}(G)\times {\mathbb Z}^{( I -1)( \Lambda -1)}$. It is known that for any finite presentation $\langle \: A\: \: R\: \rangle$ of $S$ we have $ R - A \geq \mbox{rank}(H_{2}(S))$; we say that $S$ is efficient if equality is attained for some presentation. Given a presentation $\langle \: A_{1}\: \: R_{1}\: \rangle$ for $G$, we find a presentation $\langle \: A\: \: R\: \rangle$ for $S$ such that $ R - …


Specific Determination Of Hydrogen Peroxide With A Catalase Biosensor Based On Mercury Thin Film Electrodes, F. Ni̇l Ertaş, Suna Ti̇mur, Erol Akyilmaz, Erhan Di̇nçkaya Jan 2000

Specific Determination Of Hydrogen Peroxide With A Catalase Biosensor Based On Mercury Thin Film Electrodes, F. Ni̇l Ertaş, Suna Ti̇mur, Erol Akyilmaz, Erhan Di̇nçkaya

Turkish Journal of Chemistry

A biosensor for specific determination of hydrogen peroxide was developed using catalase (EC 1.11.1.6) in combination with a mercury film electrode. Catalase was immobilized with gelatine by means of glutaraldehyde on the electrode surface. The biosensor response was monitored by following the reduction peak of dissolved oxygen at around -0.24 V. The peak current changes upon addition of hydrogen peroxide and gives a linear response in a concentration range of 1-50 x 10^{-6} M within a response time of 3 minutes.


On The Asymptotics Of Fourier Coefficients For The Potential In Hill's Equation, Haskiz Coşkun Jan 2000

On The Asymptotics Of Fourier Coefficients For The Potential In Hill's Equation, Haskiz Coşkun

Turkish Journal of Mathematics

We consider Hill's equation $y'' +(\lambda -q)y=0$ where $q\in L^{1}[0,\pi ].$ We show that if $l_{n}-$the length of the $n-th$ instability interval$-$ is of order $O(n^{-k})$ then the real Fourier coefficients $a_{n},b_{n}$ of $q$ are of the same order for$(k=1,2,3)$, which in turn implies that $q^{(k-2)}$, the $(k-2)th$ derivative of $q$, is absolutely continuous almost everywhere for $k=2,3.$


A Local Zero-Two Law And Some Applications, Radu Zaharopol Jan 2000

A Local Zero-Two Law And Some Applications, Radu Zaharopol

Turkish Journal of Mathematics

In the paper we obtain a local zero-two law for positive contractions of $L^1$-spaces, which we use in order to offer new proofs of a theorem of Orey concerning Markov chains, and of the strong asymptotic stability of certain Markov operators that have appeared in the study of the Tjon-Wu equation and in connection with the Hannsgen and Tyson model of the cell cycle.


Applications Of The Tachibana Operator On Problems Of Lifts, Abdullah Mağden, Ekrem Kadioğlu, Ari̇f A. Salimov Jan 2000

Applications Of The Tachibana Operator On Problems Of Lifts, Abdullah Mağden, Ekrem Kadioğlu, Ari̇f A. Salimov

Turkish Journal of Mathematics

The purpose of the present paper is to study, using the Tachibana operator, the complete lifts of affinor structures along a pure cross-section of the tensor bundle and to investigate their transfers. The results obtained are to some extent similar to results previously established for tangent (cotangent) bundles \lbrack 1\rbrack. However there are various important differences and it appears that the problem of lifting affinor structures to the tensor bundle on the pure cross-section presents difficulties which are not encountered in the case of the tangent (cotangent) bundle.


On Torsion-Free Barely Transitive Groups, Mahmut Kuzucuoğlu Jan 2000

On Torsion-Free Barely Transitive Groups, Mahmut Kuzucuoğlu

Turkish Journal of Mathematics

B. Hartley asked the following question: Does there exist a torsion free barely transitive group? Existence of torsion free simple barely transitive group is also unknown. We answer the latter question negatively in a special case. Moreover we proved the following: Let $G$ be a simple barely transitive group, and $H$ be a stabilizer of a point. If for a non-identity element $x \in G$, $C_G (x)$ is infinite then, $C_G (x)$ cannot contain $H$.


Multipliers Between Orlicz Sequence Spaces, P. B. Djakov, M. S. Ramanuan Jan 2000

Multipliers Between Orlicz Sequence Spaces, P. B. Djakov, M. S. Ramanuan

Turkish Journal of Mathematics

Let $M, N $ be Orlicz functions, and let $D(\ell_M , \ell_N ) $ be the space of all diagonal operators (that is multipliers) acting between the Orlicz sequence spaces $\ell_M$ and $\ell_N$. We prove that the space of multipliers $D(\ell_M , \ell_N )$ coincides with (and is isomorphic to) the Orlicz sequence space $ \ell_{M_N^{*}} ,$ where $ M_N^{*} $ is the Orlicz function defined by $M_N^{*}(\lambda ) = \sup \{ N(\lambda x) - M(x), \; x \in (0,1) \}$.


On The Metabelian Local Artin Map I: Galois Conjugation Law, Kazim İlhan İkeda Jan 2000

On The Metabelian Local Artin Map I: Galois Conjugation Law, Kazim İlhan İkeda

Turkish Journal of Mathematics

It is proved that, for a (henselian) local field $K$ and for a fixed Lubin-Tate splitting $\phi$ over $K$, the metabelian local Artin map (?, $K)_{\phi}: B(K, \phi) \tilde{\rightarrow} Gal (K^{(ab)^2} / K)$ satisfies the Galois conjugation law $$(\tilde{\sigma}^+(\alpha), \sigma (K))_{\tilde{\sigma}\phi\tilde{\sigma}^{-1}} = \tilde{\sigma} _{K^{(ab)^2}} (\alpha, K)_{\phi}\tilde{\sigma}^{-1} _{\tilde{\sigma}(K^{(ab)^2})}$$ for any $\alpha \in B(K, \phi)$, and for any embedding $\sigma : K \hookrightarrow K^{sep}$, where $\tilde{\sigma} \in$ Aut $(K^{sep}$) is a fixed extension to $K^{sep}$ of the embedding $\sigma : K \hookrightarrow K^{sep}$.


Representing Systems Of Exponentials And Projection On Initial Data In The Cauchy Problem, Yu. F. Korobeinik Jan 2000

Representing Systems Of Exponentials And Projection On Initial Data In The Cauchy Problem, Yu. F. Korobeinik

Turkish Journal of Mathematics

The Cauchy problem for the equation \begin{equation} Mw\equiv \sum_{j=0}^m\sum_{s=0}^{l_j}a_{s,j}\frac{\partial^{s+j}w(z_1,z_2)}{\partial z_1^s\partial z_2^j}=0 \end{equation} \begin{equation} \frac{\partial^nw(z_1,z_2)}{\partial z_2^n}\mid_{z_{2}=0}=\varphi_n(z_1), n=0,1,\ldots , m-1 \end{equation} is investigated under the condition $l_j\leq l_m, j=0,1,\ldots,m-1$. It is shown that the operator of projection of solution of (1) on its initial data (2) in a definite situation has a linear continuous right inverse which can be determined effectively with the help of representing systems of exponentials in the space of initial data.


Oscillation Criteria For Second Order Nonlinear Differential Equations With Damping, Aydin Ti̇ryaki̇, Ağacik Zafer Jan 2000

Oscillation Criteria For Second Order Nonlinear Differential Equations With Damping, Aydin Ti̇ryaki̇, Ağacik Zafer

Turkish Journal of Mathematics

Oscillation criteria are given for second order nonlinear differential equations with damping of the form $$(a(t) \psi (x ) \dot x)\dot{}+ p(t) \dot x + q (t) f (x ) = 0,\quad t\geq t_0,$$ where $p$ and $q$ are allowed to change signs on $[t_0,\infty)$. We employ the averaging technique to obtain sufficient conditions for oscillation of solutions of the above equation. Our results generalize and extend some known oscillation criteria in the literature.


The K-Derivation Of A Gamma-Ring, Hati̇ce Kandamar Jan 2000

The K-Derivation Of A Gamma-Ring, Hati̇ce Kandamar

Turkish Journal of Mathematics

In this paper, the $k$-derivation is defined on a $\Gamma$-ring $M$ (that is, if $M$ is a $\Gamma$-ring, $d:M\to M$ and $k:\Gamma\to \Gamma$ are to additive maps such that $d(a\beta b )= d(a)\beta b + ak(\beta)b + a\beta d(b) $ for all $a,b\in M, \quad \beta \in \Gamma$, then $d$ is called a $k$-derivation of $M$) and the following results are proved. (1) Let $R$ be a ring of characteristic not equal to 2 such that if $xry=0$ for all $x, y\in R$ then $r=0$. If $d$ is a $k$-derivation of the $(R=)\Gamma$-ring $R$ with $k=d$, then $d$ is the …


Qr-Submanifolds And Almost Contact 3-Structure, Rifat Güneş, Bayram Şahi̇n, Sadik Keleş Jan 2000

Qr-Submanifolds And Almost Contact 3-Structure, Rifat Güneş, Bayram Şahi̇n, Sadik Keleş

Turkish Journal of Mathematics

In this paper,QR-submanifolds of quaternion Kaehlerian manifolds with $\dim \nu ^{\perp }=1$ has been considered. It is shown that each QR-submanifold of quaternion Kaehlerian manifold with $\dim \nu ^{\perp }=1$ is a manifold with an almost contact 3-structure. We apply geometric theory of almost contact 3-structure to the classification of QR-submanifolds (resp.Real hypersurfaces) of quaternion Kaehler manifolds (resp.$IR^{4m}$, $m>1$). Some results on integrability of an invariant distribution of a QR-submanifold and on the immersions of its leaves are also obtained.


A Remark On The Asymptotic Properties Of Positive Homogeneous Maps On Homogeneous Lattices, Alp Eden Jan 2000

A Remark On The Asymptotic Properties Of Positive Homogeneous Maps On Homogeneous Lattices, Alp Eden

Turkish Journal of Mathematics

An abstract version of Lyapunov exponents is defined for positive homogeneous maps on Homogeneous Lattices and a sufficient condition is given for the asymptotic stability of the map.


The Pitch And The Angle Of Pitch Of A Closed Nonnull Ruled Hypersurface Whose Generator Is Spacelike In R^{K+2}_1, Ayşe Altin, Aysel Turgut Vanli Jan 2000

The Pitch And The Angle Of Pitch Of A Closed Nonnull Ruled Hypersurface Whose Generator Is Spacelike In R^{K+2}_1, Ayşe Altin, Aysel Turgut Vanli

Turkish Journal of Mathematics

In this paper, the pitch and the angle of pitch of a closed nonnull ruled hypersurface whose generators are spacelike are calculated in $R^{k+2}_1 $.


On Subspaces Isomorphic To L^Q In Interpolation Of Quasi Banach Spaces, J. A. Lopez Molina Jan 2000

On Subspaces Isomorphic To L^Q In Interpolation Of Quasi Banach Spaces, J. A. Lopez Molina

Turkish Journal of Mathematics

We show that every sequence $\{x_n\}_{n=1}^{\infty}$ in a real interpolation space $(E_0,E_1)_{\theta,q}$, $0 < \theta < 1$, $0 < q < \infty,$ of quasi Banach spaces $E_0,E_1,$ which is $0-$convergent in $E_0 + E_1$ but $\inf_n \;\ x_n\ _{(E_0,E_1)_{\theta,q}} > 0,$ has a subsequence which is equivalent to the standard unit basis of $\ell^q.$