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On Existence Of A Meromorphic Function With Infinitely Many Of Deficient Functions, Halil Ardahan Jan 1997

On Existence Of A Meromorphic Function With Infinitely Many Of Deficient Functions, Halil Ardahan

Turkish Journal of Mathematics

Let {a_n(z) : {a_n(z)}_n^w, 0 do not depend on r,0


The Linear Mean Value Of The Remainder Term In The Problem Of Asymptotic Behavior Of Eigenfunctions Of The Automorphic Laplacian, Zernişan Emi̇rleroğlu Jan 1997

The Linear Mean Value Of The Remainder Term In The Problem Of Asymptotic Behavior Of Eigenfunctions Of The Automorphic Laplacian, Zernişan Emi̇rleroğlu

Turkish Journal of Mathematics

The purpose of this paper is to obtain the estimate for the average mean value of the remainder term of the asymptotic formula for the quadratic mean value of the Fourier coefficients of the eigenfunctions over the discrete spectrum of the automorphic Laplacian.


On Hill's Equation With Piecewise Constant Coefficient, I. Yaslan, G.Sh. Guseinov Jan 1997

On Hill's Equation With Piecewise Constant Coefficient, I. Yaslan, G.Sh. Guseinov

Turkish Journal of Mathematics

In this paper the eigenvalues of the periodic and the semi-periodic boundary value problems associated with Hill's equation are investigated in the case of piecewise constant coefficient. As a corollary the asymptotic formula for the lengths of the instability intervals of Hill's equation is derived and it is shown that they increase beyond all bounds. Also, the conditions for coexistence of periodic and semi-periodic solutions are indicated.


A Characterization Of ^-Nc P-Groups, Ali Osman Asar Jan 1997

A Characterization Of ^-Nc P-Groups, Ali Osman Asar

Turkish Journal of Mathematics

In this work, presented is a partial characterization of a perfect locally nilpotent p-group in which every proper subgroup is nilpotent-by-Chernikov.


Immersions Preserved Under Rotations With Totally Reducible Focal Set, Rıdvan Ezentaş Jan 1997

Immersions Preserved Under Rotations With Totally Reducible Focal Set, Rıdvan Ezentaş

Turkish Journal of Mathematics

In [1] Carter and the author introduced the idea of an immersion f : Mm-+ Rn with totally reducible focal set (TRFS). Such an immersion has the property that, for all p E M, the focal set with base p is a union of hyperplanes in the normal plane to f(M) at f(p) . Here we show that if we take two immersions with TRFS then we can construct new immersions with TRFS. In particular, rotating an immersion with TRFS about an axis gives anew immersion with TRFS.


Quotients Of Real Algebraic Sets Via Finite Groups, Yıldıray Ozan Jan 1997

Quotients Of Real Algebraic Sets Via Finite Groups, Yıldıray Ozan

Turkish Journal of Mathematics

In this paper, we will study finite algebraic group actions on real algebraic sets and compare the topological quotient X/G with the algebraic quotient X/ /G. We will give a different and shorter proof of a result of Procesi and Schwarz, stating that if the order of the group G, acting algebraically on a real algebraic set X, is odd then X/G is equal to X/ /G. In the case of even order groups, we will a give sufficient condition ( and a necessary condition in the case G = Z_2 ) for the X / G to be equal …


Weight Equations For Binary Linear Codes And Their Applications, Ersan Akyildiz, İsmai̇l Ş. Güloğlu, Masatoshi Ikeda Jan 1997

Weight Equations For Binary Linear Codes And Their Applications, Ersan Akyildiz, İsmai̇l Ş. Güloğlu, Masatoshi Ikeda

Turkish Journal of Mathematics

Some combinatorial problems concerning binary vector spaces are solved by applying the techniques developed in [1]. These illustrate that they are effective tools for such purposes.


On Univalent Functions With Three Preassigend Values, Y. Avci, E. Zlotkiewicz Jan 1997

On Univalent Functions With Three Preassigend Values, Y. Avci, E. Zlotkiewicz

Turkish Journal of Mathematics

In this paper, univalent functions with three preassigend values are studied. The sharp bounds for the first coefficient are obtained. Moreover, the coefficient problem for a subclass of such functions is completely solved.


On Ideals Of Prime Rings With (\Sigma, \Tau)- Derivations, Q. Deng, M. Ş. Yeni̇gül, N. Argaç Jan 1997

On Ideals Of Prime Rings With (\Sigma, \Tau)- Derivations, Q. Deng, M. Ş. Yeni̇gül, N. Argaç

Turkish Journal of Mathematics

Let R be a prime ring. Let \sigma , \tau be two homomorphisms and d be a (\sigma,\tau)-derivation of R. The purpose of this paper is to prove two results: (i) If char R \neq 2, U is a non-zero ideal of R, \sigma is subjective such that \sigma (U) \neq 0, \tau is an automorphism and [d(U), d(U)]_{\sigma,\tau} = 0, then \sigma^2 = \tau^2 and \sigma \tau = \tau \sigma. (ii) Under the assumptions that either char R = 0 or char R > max {2,n}, U is a non-zero right ideal, and \sigma, \tau are automorphisms of R, suppose …


On High Order Riesz Transformations Generated By Generalized Shift Operator, İsmai̇l Eki̇nci̇oğlu, İ. Kaya Özkin Jan 1997

On High Order Riesz Transformations Generated By Generalized Shift Operator, İsmai̇l Eki̇nci̇oğlu, İ. Kaya Özkin

Turkish Journal of Mathematics

In this paper, we determine high order Riesz transformations by using generalized shift operators and giving some of their properties.


Some New Sequence Spaces Defined By A Sequence Of Moduli, Ayhan Esi̇ Jan 1997

Some New Sequence Spaces Defined By A Sequence Of Moduli, Ayhan Esi̇

Turkish Journal of Mathematics

In this paper we introduce and exaamine some properties of three sequence spaces defined by using a sequence of moduli.


The Paper On The Matrix Valued Time Series, M. Tuncay Gençoğlu Jan 1997

The Paper On The Matrix Valued Time Series, M. Tuncay Gençoğlu

Turkish Journal of Mathematics

In this paper, random series oscillatory were examine in matrix valued time series. This series' calculated correlation coefficient between elements. Positive serial correlation coefficient between terms examined relation.


A Note On Finite Hyperbolic Planes Obtained From Projektive Planes, Ş. Olgun, İ. Özgür, İ. Günaltili Jan 1997

A Note On Finite Hyperbolic Planes Obtained From Projektive Planes, Ş. Olgun, İ. Özgür, İ. Günaltili

Turkish Journal of Mathematics

Let \Pi be a finite projective plane of order n and \cal be a set, \cal = m, of any lines of \Pi which contains three non-concurrent lines. Consider the hyperbolic plane \Pi_m obtained from \Pi by removing all lines (including all points on them) of \cal. In this paper, we obtain larger values than the known maximum value of m and determine the linne classes of some hyperbolic planes of type \Pi_m. Furthermore we give an answer to a question in Bumcrot [1] about hyperbolic planes containing two-point liens.


Some Remarks On Solid State Polymerization, George Adler Jan 1997

Some Remarks On Solid State Polymerization, George Adler

Turkish Journal of Chemistry

No abstract provided.


Dielectric Studies Of Various Olefin/So2 Copolmers, B. Baysal, Candan Erbi̇l, Paul L. Morganelli, W. H. Stockmayer Jan 1997

Dielectric Studies Of Various Olefin/So2 Copolmers, B. Baysal, Candan Erbi̇l, Paul L. Morganelli, W. H. Stockmayer

Turkish Journal of Chemistry

Dielectric constant and loss have been measured at low and high frequencies for several poly(1-olefin sulfones) as well as for the polysulfones of allybenzene and allyl cyclopentane. The low-frequency dispersion in allylbenzene due to helical sequences is weaker in benzene than in dioxane, and in both solvents is much lower than for the 1-olefin polymers. Solvent effects on the high frequency process are also reported, but yield no simple uniform picture.


Synthesis Characterization And Miscibility Of Polyvinyl Butyrals Of Varying Vinyl Alcohol Contents, Z. M. Zhou, D. J. David, W. J. Macknight, F. E. Karasz Jan 1997

Synthesis Characterization And Miscibility Of Polyvinyl Butyrals Of Varying Vinyl Alcohol Contents, Z. M. Zhou, D. J. David, W. J. Macknight, F. E. Karasz

Turkish Journal of Chemistry

Polyvinyl butyrals (PVB) of systematically varying vinyl alcohol content have been synthesized and characterized using wet chemistry, IR, DSC, and TGA. The miscibility of PVB-PVB blends was studied by DSC as a function of vinyl alcohol content and vinyl alcohol content differences between the respective blend components. These data were use to construct an isothermal miscibility map of PVB and to calculate the intramolecular interaction parameter \chi_{VA,VB}. The \chi_{VA,VB} was a function of the absolute level of the vinyl alcohol (VA) and vinyl butyral (VB) contents of the polymers. In addition, the thermal stability of polyvinyl butyral was found to …


Network Characterization Of Energetic Poly(Glycidyl-Azide), Mehmet S. Eroğlu, Olgun Güven Jan 1997

Network Characterization Of Energetic Poly(Glycidyl-Azide), Mehmet S. Eroğlu, Olgun Güven

Turkish Journal of Chemistry

Energetic poly(glycidyl azide) (PGA) elastomers with different crosslink densities were prepared by varying the NCO/OH reactive-groups ratio from 0.8 to 1.0. In the preparation of the elastomers, PGA chains were end-liked with a mixture of hexamethylene diisocyanate (HMDI) and trimethylol propane (TMP) at a fixed TMP/PGA mole ratio. The number average molar mass between junction points of the network chains \overline{{\rm M}}_c was calculated using data obtained from swelling and uniaxial tensile tests and the results were compared. For the mechanical characterization of the networks, Mooney-Rivlin plots were prepared and the values of the constants 2C_1 and 2C_2 of PGA …


Synthesis Of The New Cation Exchange Resins Having Poly (Styrene-Caprolactone) Units, S. Savaşkan Yilmaz, Hulisi Özbayrak, Baki Hazer Jan 1997

Synthesis Of The New Cation Exchange Resins Having Poly (Styrene-Caprolactone) Units, S. Savaşkan Yilmaz, Hulisi Özbayrak, Baki Hazer

Turkish Journal of Chemistry

The crosslinked polystyrene-polycaprolactone , PS-PCL-, block copolymers were prepared by the copolymerization of styrene and poly(caprolacton dimethylmethacrylate) (PCL-DM). The molecular weights of polycaprolactone, PCL, PCL-DM were 1250 and 2000. The swelling in H_2O or CHCl_3 of the sulfonated and unsulfonated block copolymers were determined under comparable conditions and investigated. The capacities of the obtained ion exchange resins were 1.31 and 1.10 meq/g.


Thermal Stabilities Of Hydroxyalkyl Terminated Polydimethylsiloxane Oligomers, İskender Yi̇lgor, Emel Yi̇lgor Jan 1997

Thermal Stabilities Of Hydroxyalkyl Terminated Polydimethylsiloxane Oligomers, İskender Yi̇lgor, Emel Yi̇lgor

Turkish Journal of Chemistry

The thermal stabilities of \alpha,\omega-hydroxypropyl, \alpha,\omega-hydroxybutyl \alpha,\omega-2-hydroxypentyl and \alpha,\omega-hydroxyhexyl terminated polydimethylsiloxane oligomers were investigated. Hydroxypropyl and hydroxybutyl terminated polydimethylsiloxane oligomers showed degradation upon heating through the loss of functional end groups, as determined by FTIR spectroscopy and gel permeation chromatography. \alpha,\omega-Hydroxyhexyl and \alpha,\omega-2-hydroxypentyl terminated polydimethylsiloxane oligomers were stable under similar conditions. The instability of the end groups is due to the backbiting of the terminal silicon in the PDMS by the primary hydroxyl oxygen, leading to the formation of 5-and 6-membered stable, heterocylic compounds. Loss of end groups also resulted in a dramatic increase in the molecular weights of the …


New Synthetic Approach For The Synthesis Of Liquid Crystalline Block And Graft Copolymers, Yeşim Hepuzer, İ. Ersin Serhatli, Yusuf Yağci Jan 1997

New Synthetic Approach For The Synthesis Of Liquid Crystalline Block And Graft Copolymers, Yeşim Hepuzer, İ. Ersin Serhatli, Yusuf Yağci

Turkish Journal of Chemistry

Liquid crystalline block and graft copolymers were synthesized according to the macroinitiator and macroinimer concept. For this purpose, side chain block copolymers (polytetrahydrofuran-b-polymethylmethacrylate) having liquid crystalline 4,4'- cyanobiphenyl blocks were prepared and characterized. Unlike the liquid-crystalline homopolymer with mesogenic units in the side chain, all block and graft copolymers showed a smectic A mesophase. The transition temperatures are hardly affected by the composition and molecular weight of the blolck copolymers.


Electrical Conductivity Of Sodium Doped Poly(4-Vinylpyridine), Murat Özyalçin, Zuhal Küçükyavuz, Aref Jarvaherian, Savaş Küçükyavuz Jan 1997

Electrical Conductivity Of Sodium Doped Poly(4-Vinylpyridine), Murat Özyalçin, Zuhal Küçükyavuz, Aref Jarvaherian, Savaş Küçükyavuz

Turkish Journal of Chemistry

Poly(4-Vinylpyridine) was synthesized by free radicalic polymerization. Solution doping process with metallic sodium was carried out. A conductivity value around 10^{-6} S/cm was obtained. Relative change in the coductivity with dopant concentration, temperature dependence of conductivity, conductivity behavior in atmospheric conditions for the samples were analyzed. SEM and EDX techniques were also used for the characterization of the polymer.


Conducting Polymer Grafts Of Polypyrrole, Levent Toppare Jan 1997

Conducting Polymer Grafts Of Polypyrrole, Levent Toppare

Turkish Journal of Chemistry

Conducting polymer grafts of pyrrole with poly[(methyl methacrylate)-co-(2-(N-pyrollyl) ethyl methacrylate)] wwere synthesized via elctrochemical polymerization of pyrrole in different media. Samples were characterized by SEM, thermal analysis and conductivity measurements.


Crystal Structure Effect In Radiation-Induced Solid-State Polymerization Of Acrylamide, Ali Usanmaz Jan 1997

Crystal Structure Effect In Radiation-Induced Solid-State Polymerization Of Acrylamide, Ali Usanmaz

Turkish Journal of Chemistry

Crystal structure of arcylamide at -150^{\circ}C was studied to understand the role of the crystal structure on the reaction mechanism of radiation-induced polymerization in the solid-state. Acrylamide crystallizes in the monoclinic unit cell with the unit cell parameters as ; a=828.0(2) pm, b=578.0(4) pm, c=974.9(2) pm, \beta=119.62(4)^0, space group =P 2_1/c, Z=4 molecules/unit cell, d_x = 1.165 g/cm^3. From the results of the structural data a polymerization mechanism in the solid-state is suggested. The radiation damage in single crystal of acrylamide was also investigated in detail. The result showed the formation of the amorphous polymer, that phase separated from the …


Electrical Conductivities Of Poly (Alkyl Vinyl Ketones) Reacted With Dopant Solutions, Jun Hui Ma, J. David Tauber, Ülkü S. Ramelow Jan 1997

Electrical Conductivities Of Poly (Alkyl Vinyl Ketones) Reacted With Dopant Solutions, Jun Hui Ma, J. David Tauber, Ülkü S. Ramelow

Turkish Journal of Chemistry

Poly ethyl vinyl ketone (PEVK) and poly methyl vinyl ketone (PMVK) were prepared using photochemical processes. The irradiation of monomers with UV light provides a new method, different from the methods previously used for the polymerization of these monomers. FTIR and UV spectroscopies were used for the structure and reaction mechanism of the polymers. NMR was used to calculate the conversion percentage of MVK and EVK polymers. The conductivity change at various temperatures was traced during reactions of PMVK and PEVK with various dopant concentrations and the activation energy of these reactions were calculated by adding dopants and by adjusting …


A Two-Dimensional Monte Carlo Polymerization Of 5-Membered Rings, Okan Esentürk, H. Önder Pamuk, E. Yurtsever Jan 1997

A Two-Dimensional Monte Carlo Polymerization Of 5-Membered Rings, Okan Esentürk, H. Önder Pamuk, E. Yurtsever

Turkish Journal of Chemistry

A modification of the kinetic growth model in two dimensions for the polymerization of 5-membered rings is presented. The preliminary results reveal the validity of the modified model.


Calculation Of Spreading Pressure Of Water On Cellulosic Films From Contact Angle Data, H. Yıldırım Erbi̇l Jan 1997

Calculation Of Spreading Pressure Of Water On Cellulosic Films From Contact Angle Data, H. Yıldırım Erbi̇l

Turkish Journal of Chemistry

The correlations between the surface properties of the modified cellulose papers with their toner compatibility were investigated. The surface tension components of the cellulosic films, their interfacial tension with the liquid drops and the work of adhesion components were calculated using van Oss-Good's One-Liquid contact angle approach. The electron donor (or Lewis base) \gamma^- components of the cellulosic films were found to represent the main interactions with the the electron acceptor (acidic) \gamma^+ components of the contacting liquids. Allyl ketene dimer (AKD) grafting of the cellulose affected the surface properties; the higher the substitution of the hydroxyl group, the smaller …


Phase Transition Of Hydrolyzed Polyacrylamide Gels In Aqueous Solutions Of Poly(Ethylene Glycol), Nilhan Kayaman, Oğuz Okay, B. M. Baysal Jan 1997

Phase Transition Of Hydrolyzed Polyacrylamide Gels In Aqueous Solutions Of Poly(Ethylene Glycol), Nilhan Kayaman, Oğuz Okay, B. M. Baysal

Turkish Journal of Chemistry

Hydrolyzed polyacrylamide gels immersed in aqueous solutions of poly(ethylene glycol) (PEG) of molecular weight 300 exhibit a discontinuous volume change upon continuous increase of the PEG concentration in the external solution. As the duration of hydrolysis increases, that is, as the proportion of the ionic groups on the network chains increases, the critical concentration of PEG required for a discontinuous volume change rises and, also, the magnitude of the volume collapse becomes larger. Experimental results indicate that the gel collapse in PEG solution is due to the osmotic deswelling of the ionic gel rather than due to a complex formation …


A Quantum-Chemical Investigation On 5,5'-Bi(1h-1.2,4-Triazole)), A. A. İki̇zler, R. Abbasoğlu, N. Saltek, M. Şeri̇fova Jan 1997

A Quantum-Chemical Investigation On 5,5'-Bi(1h-1.2,4-Triazole)), A. A. İki̇zler, R. Abbasoğlu, N. Saltek, M. Şeri̇fova

Turkish Journal of Chemistry

The conformational analysis of flexible 5,5'-bi(1H-1,2,4-triazole) molecule containing various reaction centers has been performed by the semiempirical methods MNDO,AM1 and PM3, and the internal rotation barrier calculated. The most stable conformation of the molecule has been determined to be the planar trans conformation. According to the three methods, 5,5'-bi(1H-1,2,4-triazole) molecule (C) has been found to be relatively more stable than its tautomer 3,3'-bi(1H-1,2,4-triazole)(B) and to be less stable than its other tautomer 3,3'-bi(4H-1,2,4-triazole)(A). Moreover, the electronic properties of 5,5'-bi(1H-1,2,4-triazole) molecule and the effect of conformational changing on electronic and geometric properties have also been investigated. To determine the protonation sites …


High Rates Of Fluorescence Quenching Between Perylene Dodecyldiimide And Certain \Pi-Electron Donors, S. İçli̇, H. İci̇l, İ. Gürol Jan 1997

High Rates Of Fluorescence Quenching Between Perylene Dodecyldiimide And Certain \Pi-Electron Donors, S. İçli̇, H. İci̇l, İ. Gürol

Turkish Journal of Chemistry

Perylene bis-n-dodecyl diimide is found to quench fluorescenc emissions of naphthalene, phenanthrene and dihydrocarbazolocarbazole molecules at rates of 4.4\times10^{11}, 2.8\times10^{12} and 2.5\times10^4 M^{-1} sec^{-1}, in respective order of aromaticity. These unusulally high rates of fluorecence quenchings are attributed to Perrin model static quenching and presence of electron transfer through singlet excited state of perylene diimide. Calculated free energy of electron transfer, \Delta G_{ET}=-120.5 kJ/mol, between perylene diimide and dihydrocarbazolocarbazole is taken as evidence for observation of high fluorescence quenching rate for carbazolocarbazole molecule. Keywords: Fluorescence quenching, Photoenergy transfer, Perylene diimide and Carbazolocarbazole


Possible Roles Of Transition Metals In Cloudwater Relative To The Solar Short-Wave Radiation Absorption Anomaly, Xudong Huang, S. Sinan Keski̇n, Francis Pink, İlhan Ölmez Jan 1997

Possible Roles Of Transition Metals In Cloudwater Relative To The Solar Short-Wave Radiation Absorption Anomaly, Xudong Huang, S. Sinan Keski̇n, Francis Pink, İlhan Ölmez

Turkish Journal of Chemistry

Measurements of the absorption of solar short-wave radiation by clouds exceed those predicted by theoretical calculations. In order to understand the roles of minor and trace species in this absorption anomaly, cloudwater samples were collected from individual precipitating clouds and analyzed for trace metals and anionic species. Two generalized approaches were used to assess the direct impact of the absorption of solar short-wave radiation by transition metals and/or their anionic complexes. Additionally, it was suggested that iron and manganese may act as catalyts in the formation of sulfate aerosols which efficiently scatter solar radiation.