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Full-Text Articles in Physical Sciences and Mathematics

Segal Algebra As An Ideal In Its Second Dual Space, Heybet S. Mustafayev Jan 1999

Segal Algebra As An Ideal In Its Second Dual Space, Heybet S. Mustafayev

Turkish Journal of Mathematics

For a locally compact group G, let S(G) be a symmetric Segal algebra. We prove that S(G) is an ideal in its second dual space if and only if G is compact, where the second dual is equipped with an Arens multiplication.


Some Results On Space-Like Line Congruences And Their Space-Like Parameter Ruled Surface, E. Özyilmaz Jan 1999

Some Results On Space-Like Line Congruences And Their Space-Like Parameter Ruled Surface, E. Özyilmaz

Turkish Journal of Mathematics

Using dual vectors, space-like ruled surfaces was introduced in [2]. In this paper, we define space-like line congruence and their space-like parameter ruled surfaces {\mathbf R_{11}(t)} and {\mathbf R_{21}(t)} of R_1^3. Then, by choosing space-like parameter ruled surfaces as space-like principle ruled surfaces, we obtain some relations among the magnitudes of space-like ruled surfaces {\mathbf R_1(t)}, {\mathbf R_{11}(t)}.


Cycloidal Normal Subgroups Of Hecke Groups Of Finite Index, İsmai̇l Naci̇ Cangül, Osman Bi̇zi̇m Jan 1999

Cycloidal Normal Subgroups Of Hecke Groups Of Finite Index, İsmai̇l Naci̇ Cangül, Osman Bi̇zi̇m

Turkish Journal of Mathematics

Cycloidal normal subgroups, that is, subgroups with only one cusp, of finite index of Hecke groups, which have been introduced by E. Hecke, and can be thought of as some kind of generalisation of the well-known modular group, are studied. It is shown that they correspond to cyclic quotients of Hecke groups and therefore have non-compact associated Riemann surfaces with a cusp. Finally, their total number have been formulated.


Augmented Noetherian Graded Modules, Mashhoor Refai̇ Jan 1999

Augmented Noetherian Graded Modules, Mashhoor Refai̇

Turkish Journal of Mathematics

Let $G$ be a multiplicative group with identity $e$, and let $R$ be an associative $G$-graded ring with unity 1. In this paper we study the augmented graded Noetherian modules and try to give some relationships between the Noetherian modules in the category $R-Agr$ and the Noetherian modules in the category $R_e-gr$.


Generalized Solutions Of A Class Of Linear And Quasi-Linear Degenerated Hyperbolic Equations, Rossitza Semerdjieva Jan 1999

Generalized Solutions Of A Class Of Linear And Quasi-Linear Degenerated Hyperbolic Equations, Rossitza Semerdjieva

Turkish Journal of Mathematics

The equation $L(u):=k(y)u_{xx}-\partial_y(\ell(y)u_y)+r(x,y)u=f(x,y,u),$ where $k(y)>0, \ell(y)>0$ for $y>0,k(0)=\ell(0)=0$ and $lim_{y\rightarrow 0}k(y)/\ell(y)$ exists, is strictly hyperbolic for $y>0$ and its order degenerates on the line $y=0$. We consider the boundary value problem $Lu=f(x,y,u)$ in $G, u\mid_{AC}=0$, where $G$ is a simply connected domain in $R^2$ with piecewise smooth boundary $\partial G=AB\cup AC\cup BC; AB=\{(x,0): 0\leq x\leq 1\}, AC : x=F(y) =\int_0^y(k(t)/\ell (t))^{1/2}dt$ and $BC: x=1-F(y)$ are characteristic curves. The existence and uniqueness of a generalized solution to this problem are proved in the linear case (where $f=f(x,y));$ the nonlinear case is treated by using the Schauder Fixed …


The Isometries Of The Bochner Space L^P(\Mu,H), Bahatti̇n Cengi̇z Jan 1999

The Isometries Of The Bochner Space L^P(\Mu,H), Bahatti̇n Cengi̇z

Turkish Journal of Mathematics

In this article, the known characterization of the surjective linear isometries of the Bochner space $L^p(\mu, H)$, for a $\sigma$-finite measure $\mu$ and an arbitrary Hilbert space $H$, in terms of regular set isomorphisms of the $\sigma$-algebra involved and strongly measurable families of surjective isometries of $H$, is extended to arbitrary measures.


Structure Of M-Dimensional Implicitly Defined Surfaces In N-Dimensional Euclidean Space E_N, Alla Borisovna Kotlyar Jan 1999

Structure Of M-Dimensional Implicitly Defined Surfaces In N-Dimensional Euclidean Space E_N, Alla Borisovna Kotlyar

Turkish Journal of Mathematics

We consider the structure of the surface in the given point, if we vary all its normals in this point.


Modular Symmetry Classes Of Tensors, M. Shahryari, M. A. Shahabi Jan 1999

Modular Symmetry Classes Of Tensors, M. Shahryari, M. A. Shahabi

Turkish Journal of Mathematics

We introduce the notion of modular symmetry classes of tensors and give a necessary and sufficient condition for a modular symmetry class of tensors associated with the full symmetric group to be non-zero. Then we use modular symmetry classes of tensors to study the polynomial representations of $GL(V)$, where $V$ is a vector space over a field of characterisitic $p$. At the end we introduce a non-degenerate bilinear form on a modular symmetry class. Some problems are also given.


Two Lemmas On Formal Power Series, Kazim İlhan İkeda, Masatoshi İkeda Jan 1999

Two Lemmas On Formal Power Series, Kazim İlhan İkeda, Masatoshi İkeda

Turkish Journal of Mathematics

Let $L$ be a local field and $\tilde{L}$ the completion of the maximal unramified extension of $L$. In this short note, we prove \noindent (I) the sequences \noindent (1$^{\prime\prime}$) $0\rightarrow {\cal O}_L$[[$X_1,\ldots,X_n$]]$\rightarrow{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]] $\stackrel{\phi_L-1}{\ra}{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]]$\rightarrow 0$ \noindent and \noindent (2$^{\prime\prime}$) $1\rightarrow {\cal O}_L$[[$X_1,\ldots,X_n$]]$^x\rightarrow{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]] $^x\stackrel{\phi_L-1}{\ra}{\cal O}_{\tilde{L}}$[[$X_1,\ldots,X_n$]]$\rightarrow 1$ \noindent are exact, where $\theta_L$ is the Frobenius automorphism over $L$ applied on the coefficients of ${\cal O}_{\tilde{L}}$[[$X_1,\ldots, X_n$]], and $\theta_L-1$ respectively denotes the mapping $\alpha\mapsto\alpha^{\theta L}-\alpha$ for \noindent (1$^{\prime\prime}$) and $\epsilon\mapsto\frac{\epsilon^{\phi}L}{\epsilon}$ for (2$^{\prime\prime}$); \noindent (II) ${\cal C}^{\circ}(\tilde{L},h)$ being the group the Coleman power series of degree 0, the sequence $$ 1\rightarrow {\cal …


A Class Of Banach Algebras Whose Duals Have The Schur Property, H. Mustafayev, A. Ülger Jan 1999

A Class Of Banach Algebras Whose Duals Have The Schur Property, H. Mustafayev, A. Ülger

Turkish Journal of Mathematics

Call a commutative Banach algebra $A$ a $\gamma$-algebra if it contains a bounded group $\Gamma$ such that $\overline{aco(\Gamma)}$ contains a multiple of the unit ball of $A$. In this paper, first by exhibiting several concrete examples, we show that the class of $\gamma$-algebras is quite rich. Then, for a $\gamma$-algebra $A$, we prove that $A^{\star}$ has the Schur property iff the Gelfand spectrum $\sum$ of $A$ is scattered iff $A^{\star}=ap(A)$ iff $A^{\star}=\overline{Span(\sum)}$.


Masatoshi Gündüz İkeda, Mehpare Bi̇lhan Jan 1999

Masatoshi Gündüz İkeda, Mehpare Bi̇lhan

Turkish Journal of Mathematics

No abstract provided.


The Weight Equations For Binary Linear Codes, Ersan Akyildiz, İsmai̇l Ş. Güloğlu, Masatoshi Ikeda Jan 1999

The Weight Equations For Binary Linear Codes, Ersan Akyildiz, İsmai̇l Ş. Güloğlu, Masatoshi Ikeda

Turkish Journal of Mathematics

The system of weight equations for a binary $(n, m)$-code with respect to its ordered basis is introduced. It connects certain quantities (characteristics) related to the basis with the weights of non-zero words in the code. It is shown that the portion involving the variables does not depend neither on the code nor on the basis. Explicit forms of the matrix of coefficients in the system and its inverse matrix are computed.


A Survey On Drinfeld Modular Forms, Ernst-Ulrich Gekeler Jan 1999

A Survey On Drinfeld Modular Forms, Ernst-Ulrich Gekeler

Turkish Journal of Mathematics

No abstract provided.


On The Artin Conductor F_{Artin}(\Chi) Of A Character \Chi Of Gal (E/K) I: Basic Definitions, Kazim İlhan İkeda Jan 1999

On The Artin Conductor F_{Artin}(\Chi) Of A Character \Chi Of Gal (E/K) I: Basic Definitions, Kazim İlhan İkeda

Turkish Journal of Mathematics

Let $K$ be a local field with finite residue class field and $E$ a finite Galois extension over $K$. In this paper, we study the Artin conductor $\frak f_{\rm Artin}(\chi_\rho)$ of a character $\chi_\rho$ associated to a representation $\rho:\mbox{Gal}(E/K)\rightarrow GL(V)$ of $\mbox{Gal}(E/K)$ with metabelian kernel $\mbox{ker}(\rho)$. In order to do so, we first review the Artin character $a_{\mbox{Gal}(E/K)}$ of $\mbox{Gal}(E/K)$ and review the metabelian local class field theory. We finally propose the definition of the conductor $\frak f(E/K)$ of a metabelian extension $E/K$ in the sense of Koch-de Shalit local class field theory, and compute $\frak f_{\rm Artin}(\chi_\rho)$ under a …


The Projectivity Of The Fundamental Group Of An Affine Line, Moshe Jarden Jan 1999

The Projectivity Of The Fundamental Group Of An Affine Line, Moshe Jarden

Turkish Journal of Mathematics

No abstract provided.


On The Asymptotic Behavior Of Heegner Points, Jan Nekovar, Norbert Schappacher Jan 1999

On The Asymptotic Behavior Of Heegner Points, Jan Nekovar, Norbert Schappacher

Turkish Journal of Mathematics

We prove that all but finitely many Heegner points on a given modular elliptic curve (or, more generally, on a given quotient of the modular Jacobian variety $J_0(N)$) are of infinite order in the Mordell-Weil group where they naturally live, i.e., over the corresponding ring class field.


Shafarevich-Tate Set For Y^4 = X^4 _ L^2, Takashi Ono Jan 1999

Shafarevich-Tate Set For Y^4 = X^4 _ L^2, Takashi Ono

Turkish Journal of Mathematics

No abstract provided.


On Generalized Shioda - Inose Structures, H. Önsi̇per, Si̇nan Sertöz Jan 1999

On Generalized Shioda - Inose Structures, H. Önsi̇per, Si̇nan Sertöz

Turkish Journal of Mathematics

No abstract provided.


Impedance Characteristics Of Conducting Polypyrrole-Poly(Ethylvinylether) Graft Films, E. Kalaycioğlu, Levent Toppare, T. Grchev, M. Cvetkovska, Y. Yağci Jan 1999

Impedance Characteristics Of Conducting Polypyrrole-Poly(Ethylvinylether) Graft Films, E. Kalaycioğlu, Levent Toppare, T. Grchev, M. Cvetkovska, Y. Yağci

Turkish Journal of Chemistry

Impedance characterization of graft copolymers of poly(2-(N-pyrrolyl)ethylvinylether) and polypyrrole (doped with BF_4^-) was elucidated in comparison with pure polypyrrole doped with BF_4^-.


^{13}C-And ^{31}P-Nmr Study Of Tetracarbonylbis(Diphenylphosphino)Alkanemetal(0) Complexes Of The Group 6 Elements, Zahi̇de Özer, Sai̇m Özkar Jan 1999

^{13}C-And ^{31}P-Nmr Study Of Tetracarbonylbis(Diphenylphosphino)Alkanemetal(0) Complexes Of The Group 6 Elements, Zahi̇de Özer, Sai̇m Özkar

Turkish Journal of Chemistry

Tetracarbonylbis(diphenylphosphino)alkanemetal(0) complexes of the general formula M(CO)_4[(C_6H_5)_2P (CH_2)_nP(C_6H_5)_2] (M: Cr, Mo, W; n: 1, 2, 3) were synthesized from the reaction of M(CO)_4(\eta^{2:2}-1,5-cyclooctadiene) with the appropriate ligand and characterized by means of IR and NMR (^{13}C and ^{31}P) spectroscopy. Spectroscopic data shows that two phosphorus atoms in the complexes are identical and occupy two cis-coordiantion sites in a pseudo-octahedral coordination sphere of the metal. The comparative study of the coordination shift and the ^{31}P-^{13}C coupling constant reveals that two carbonyl groups trans to one of two phosphorus atoms in the diphosphine ligand are shifted toward the lower magnetic field more …


Chemical Constituents Of Centaurea Cuneifolia, Ümi̇t Aslan, Sevi̇l Öksüz Jan 1999

Chemical Constituents Of Centaurea Cuneifolia, Ümi̇t Aslan, Sevi̇l Öksüz

Turkish Journal of Chemistry

The whole plant material fo Centaurea cuneifolia Sm. afforded three sesquiterpene lactones; cnicin (1), dehydromelitensin (2) and dehydromelitensin-8-[(2^{'}-\alpha-hydroxy-\beta- hydroxyethyl)-acryloyl)] (3), the lignan; (-)-arctigenin (4), flavonoids; salvigenin (5), eupatilin (6), jaceosidin (7), acacetin (8), kaemferol (9), 5,7,4^{'}-trihydroxy-3-methylether (10), 5-hydroxy-3^{'},^{'},6,7-tetramethoxyflavone (11) and 5-hydroxy-3^{'},4^{'},7,8-tetramet hoxyflavone (12), a triterpene; \alpha-amyrin and a sterol; \beta-sitosterol. The structures of the isolates were determined by IR, UV, ^1H and ^{13}C NMR and MS spectroscopy.


Effects Of Ozonation On Cod Elimination Of Substituted Aromatic Compounds In Aqueus Solution, Şermi̇n Gül, Osman Seri̇ndağ, Hami̇t Boztepe Jan 1999

Effects Of Ozonation On Cod Elimination Of Substituted Aromatic Compounds In Aqueus Solution, Şermi̇n Gül, Osman Seri̇ndağ, Hami̇t Boztepe

Turkish Journal of Chemistry

The chemical oxygen demand (COD) change of various substituted aromatic compounds, namely benzoic acid, p-aminobenzoic acid, p-toluenesulfonic acid, sulfanilic acid, nitro benzene, resorcinol, p-cresol, o- cresol, o-toluidine, aniline and 8-hydroxyquinoline were investigated at ozone doses of 5, 10, 15 and 20 mg O_{3}\cdotmin^{-1}, respectively. Percent COD removal of initial compounds after ozonation was compared with reported biodegradation results. The pH change and percent removal of selected compounds were also evaluated in ozone does of 20 mg O_{3}\cdotmin^{-1} up to 80 min. ozonation. The results showed that high ozone doses are needed to obtain better elimination of initial compounds and also …


An Efficient Acetylation Of Primary And Secondary Aliphatic Alcohols With Acetic Anhydride In The Presence Of Graphite Bisulphate, Hasan Seçen, A. Hami̇t Kalpar Jan 1999

An Efficient Acetylation Of Primary And Secondary Aliphatic Alcohols With Acetic Anhydride In The Presence Of Graphite Bisulphate, Hasan Seçen, A. Hami̇t Kalpar

Turkish Journal of Chemistry

In cyclohexane, thirteen examples of primary and secondary aliphatic alcohols were easily converted to the corresponding acetate derivatives within a short time, ranging from 5 min to 2.5 h, and in good yields close to 90%, using acetic anhydride as reagent and graphite bisulphate as an efficient catalyst.


Thermodynamics Of The Dissociation Of Chromium Soap Solutions In Benzene-Dimethyl Formamide, Hüseyi̇n Topallar, Yüksel Bayrak Jan 1999

Thermodynamics Of The Dissociation Of Chromium Soap Solutions In Benzene-Dimethyl Formamide, Hüseyi̇n Topallar, Yüksel Bayrak

Turkish Journal of Chemistry

Critical micelle concentrations and dissociation constants for chromium soaps (myristate, palmitate and stearate) in a mixture of benzene and dimethyl formamide (7:3, vol/vol) were determined by means of conductivity measurements. These soaps behave as simple moderate electrolytes in dilute solutions. Critical micelle concentrations and dissociation constants decreased with increasing numbers of carbon atoms in the soap molecules. Thermodynamic parameters such as heat of dissociation, \DeltaH_d, change in free energy, \DeltaG_d, and entropy, \DeltaS_d, per mole for the dissociation process were also evaluated.


The Effect Of Phosphate Ions (Po^{3-}_4) On The Corrosion Of Iron In Sulphat Solutions, Günay Kilinççeker, B. Yazici, M. Erbi̇l, H. Gali̇p Jan 1999

The Effect Of Phosphate Ions (Po^{3-}_4) On The Corrosion Of Iron In Sulphat Solutions, Günay Kilinççeker, B. Yazici, M. Erbi̇l, H. Gali̇p

Turkish Journal of Chemistry

The effect of phosphate ions on the corrosion of iron in sulphate solutions at different temperatures (293 K, 313 K, 333 K and 353 K) and at different pH (pH=2.1, 7.2 and 12.3) values was investigated. The electrochemical three-electrode technique was employed. The cathodic and anodic current-potential curves were obtained by strating from the corrosion potential measured against SCE and polarizing it first in cathodic and then in anodic direction. The results obtained indicate that at high pH (pH=7.2 and 12.3) SO^{2-}_{4}+PO^{3-}_{4}ions together reduce the corrosion rate of iron to a greater extent than SO^{2-}_{4} alone. At low pH (pH=2.1), …


The Role Of Electrolytically Co-Deposited Platinum-Palladium Electrodes On The Electrooxidation Of D. Glucose In Alkaline Medium: A Synergistic Effect, İpek Beceri̇k Jan 1999

The Role Of Electrolytically Co-Deposited Platinum-Palladium Electrodes On The Electrooxidation Of D. Glucose In Alkaline Medium: A Synergistic Effect, İpek Beceri̇k

Turkish Journal of Chemistry

The electrooxidation of D. glucose was investigated on platinum-palladium alloy electrodes of different compositions in alkaline aqueous solutions. The surface characteristics of the alloys in contact with electrolytic solution were studied using cyclic voltammetry. In particular, a surface enrichment in platinum due to a preferential dissolution of palladium was shown. Enhanced electrocatalytic activity at about 37 at. % in Pd was obtained when compared to pure metals, thus leading to a synergistic effect. The electrocatalytic activity of different alloys for D. glucose oxidation has been chacterized by exchange current densities obtained from extrapolation of Tafel lines to calculated equilibrium potential. …


Synthesis And Spectral Characterisation Of Novel Azo-Azomethine Dyes, Hati̇ce Karaer, İsmai̇l E. Gümrükçüoğlu Jan 1999

Synthesis And Spectral Characterisation Of Novel Azo-Azomethine Dyes, Hati̇ce Karaer, İsmai̇l E. Gümrükçüoğlu

Turkish Journal of Chemistry

The synthesis of novel azo-azomethine dye derivatives of substituted Schiff bases were carried out by the reaction of substituted 1-naphtylamine with 4-nitro and 2-chloro benzenediazonium tetraflouroborate salts as a coupling component. These compounds were identified by IR, UV-Vis and ^1H-NMR spectroscopic techniques, and elemental analysis.


Electrooxidation Of Linear Alkyl Benzene Sulfonate (Las) On Pt Electrodes, Bi̇rgül Yazici, Si̇bel Zor Jan 1999

Electrooxidation Of Linear Alkyl Benzene Sulfonate (Las) On Pt Electrodes, Bi̇rgül Yazici, Si̇bel Zor

Turkish Journal of Chemistry

The electrochemical behaviour of linear alklybenzene sulfonate (LAS) on Pt electrodes was investigated in 0.05M Na_2SO_4 and in 0.1M NaCl at pH=8 by the potentiokinetic method and by electrolysis. The anodic and cathodic semilogarithmic current-potential curves were obtained between -1.6V - +1.6V. The experimental discharge potentials were determined by means of current-potential-curves obtained by electrolysis between 0-3V. The percentages of surface active material remaining in the solution after specified periods (0-6hrs) were determined for different initial concentrations of LAS (30, 150, 300 ppm) by using a potentiostat at +1.6V and by applying a potential of 20V via a direct current …


The Application Of A Scanning Electron Microscope With An Energy Dispersive X-Ray Analyser (Sem/Edxa) For Gunshot Residue Determination On Hands For Some Cartridges Commonly Used In Turkey, Kezban Gökdemi̇r, Ertan Seven, Yüksel Sarikaya Jan 1999

The Application Of A Scanning Electron Microscope With An Energy Dispersive X-Ray Analyser (Sem/Edxa) For Gunshot Residue Determination On Hands For Some Cartridges Commonly Used In Turkey, Kezban Gökdemi̇r, Ertan Seven, Yüksel Sarikaya

Turkish Journal of Chemistry

The primers of the 10 commonly used cartridges in Turkey, MKE MP5, GECO Luger, FC Luger, WIN Luger, S&B Luger, WRA Luger, FNB Luger, P Luger, KF 80 Luger and SINTOX ACTION Luger were first examined with a SEM/EDXA. Then these cartridges used in test firings and the GSR on the hands of the test shooters was collected using adhesive-coated sample stubs and examined with a SEM/EDXA. Samples were scanned by viewing the BSE (Backscattered electron) image and, brighter and spherical particles were located, and then analysed with an EDXA. The elemental compositions of the GSR of the studied cartridges …


Electrochemical Preparation And Sensor Properties Of Conducting Polyaniline Films, M. Özden Eki̇nci̇, Ergün Eki̇nci̇, A. Ersi̇n Karagözler Jan 1999

Electrochemical Preparation And Sensor Properties Of Conducting Polyaniline Films, M. Özden Eki̇nci̇, Ergün Eki̇nci̇, A. Ersi̇n Karagözler

Turkish Journal of Chemistry

A polyaniline-glucose oxidase electrode was prepared by the electrochemical polymerization of aniline on a Pt electrode that was already pre-adsorbed by the enzyme (glucose oxidase) at a potential of 1 V vs. Ag/AgCl. Then, the amperometric responses of the enzyme electrode to the electroactive hydrogen peroxide formed by the enzyme-catalyzed reaction of the substrate (glucose) with oxygen were measured at a potential of 0.7 V in PBS solution. The effects of electrochemical polymerization (i.e., concentrations of monomer and electrolyte, film thickness) and amperometric measurement parameters (i.e. pH, temperature) on the amperometric response characteristics to glucose of the resultant enzyme electrode …