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A Two-Dimensional Monte Carlo Polymerization Of 5-Membered Rings, Okan Esentürk, H. Önder Pamuk, E. Yurtsever
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.
Phase Transition Of Hydrolyzed Polyacrylamide Gels In Aqueous Solutions Of Poly(Ethylene Glycol), Nilhan Kayaman, Oğuz Okay, B. M. Baysal
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
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
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
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.
Constituents Of Salvia Verticillata, Ufuk Sönmez, Gülaçtı Topçu, Ayhan Ulubelen
Constituents Of Salvia Verticillata, Ufuk Sönmez, Gülaçtı Topçu, Ayhan Ulubelen
Turkish Journal of Chemistry
Three new and fourteen known compounds were isolated from the roots of {\it Salvia verticillata L.} Spectral methods were used for the structure determination besides TLC comparisons with authentic samples for the known compounds.
The Reliability Of Jung-Biggs-Moorhead Method For Cholesterol Determination In The Presence Of Ergosterol, Lemi Türker, Şahinde Demi̇rci̇, Marjan Akdağ
The Reliability Of Jung-Biggs-Moorhead Method For Cholesterol Determination In The Presence Of Ergosterol, Lemi Türker, Şahinde Demi̇rci̇, Marjan Akdağ
Turkish Journal of Chemistry
In the present study, the reliability of Jung-Biggs-Moorhead method for cholesterol determination has been tested in the presence of another steroid, ergosterol. It was observed that presence of ergosterol interferes with the absorbance measurement of cholesterol. When both steroids are present in the sample maximum absorption wavelength are not shifted by the mutual interaction but absorbance values are changed considerably. Therefore this method may be used only for qualitative bu not quantitative analysis for cholesterol in the presence of ergosterol.
Immobilization Of Glucose Oxidase And Urease In Hydrogel Matrices, İhsan Gürel, M.Yakup Arica, Vasıf Hasirci
Immobilization Of Glucose Oxidase And Urease In Hydrogel Matrices, İhsan Gürel, M.Yakup Arica, Vasıf Hasirci
Turkish Journal of Chemistry
Immobilization of glucose oxidase and urease in hydrogels of 2-hydroxyethyl methacrylae, and N-vinyl pyrrolidone (NVP) was achieved by irradiation (using UV kand \gamma- rays). The effect of radiation on entrapment efficiencies, retention of activities and swelling rates was obtained. To optimize the system, duration of exposure, reaction temperature, co-monomer concentrations, initiator and cross linker compositions were varied. The repeated reusability of the generated products was also tested. It was found that\gamma-irradiation at very low temperatures did not have a detrimental effect on the enzyme activity. Incorporation of more hydrophilic monomer (NVP), influenced matrix morphology and entrapment efficiencies and retained enzyme …
Photoelectron Spectroscopy: A Tool In Sorption Studies, Şefik Süzer, Hasan N. Erten
Photoelectron Spectroscopy: A Tool In Sorption Studies, Şefik Süzer, Hasan N. Erten
Turkish Journal of Chemistry
Photoelectron spectroscopy using AlK\alpha (h\nu=1486.3 eV) has been applied to study the sorption of Cs^+, Sr^{2+}, Ba^{2+}, Zn^{2+} and Co^{2+} on magnesite kaolinite, smectite and chlorite. From the observed intensities of photoelectron peaks it was determined that in magnesite the sorption affinity of the above ions follow the order: Ba^{2+}>Co^{2+}\congSr^{2+}\congZn^{2+}>Cs^+. The order for the sorption of Ba^{2+} and Cs^+ are also determined as chlorite>magnesite>smectite>kaolinite and smectite>chlorite\congkaolinite>magnesite, respectively.
A Topological Approach To The Stabilities Of Isomeric Hückel And Mobius Type Cyclacenes, Lemi Türker
A Topological Approach To The Stabilities Of Isomeric Hückel And Mobius Type Cyclacenes, Lemi Türker
Turkish Journal of Chemistry
Within the constraints of Hückel molecular orbital theory, Hückel and Mobius type cyclacenes were investigated in terms of their angle of total \pi-electron energy, O_{\pi}, and cos O_{\pi} to find out how structural changes affect the stabilities. It has been theoretically deduced that as the number of benzenoid rings (R) increases the isomeric Hückel and Mbius type cyclacenes should have comparable stabilities, although for low values of R odd-Hückel type and even-Mobius type are predicted to be more stable.
Hydrolysis And Condensation Reactions Of Methacrylate-Modified Aluminum Alkoxides, Ertuğrul Arpaç, Efraim Avşar
Hydrolysis And Condensation Reactions Of Methacrylate-Modified Aluminum Alkoxides, Ertuğrul Arpaç, Efraim Avşar
Turkish Journal of Chemistry
The hydrolysis of aluminum tri-sec-butoxide and compounds obtained by substituting the larger functional groups for the present alkly groups in Al(O-sec-Bu)_3, and the reaction of these products with a polymerizable organic ligand, i.e. methacrylic acid, were studied together with the hydrolysis reactions of the final products. A good method of preparing high-tech materials and new composites uses organo-substituted silicon esters and/or alkoxides of various elements in a polycondensation process. Introducing a suitable organic network into the inorganic backbone gives desirable properties in new coating materials. The preparation of such materials is possible via the hydrolysis of metal alkoxides. Usually, different …
Potentiometric And Spectroscopic Determinaton Of Acid Dissociation Constants Of Some Phenols And Salicylic Acids, Rahmiye Aydin, Ulviye Özer, Naciye Türkel
Potentiometric And Spectroscopic Determinaton Of Acid Dissociation Constants Of Some Phenols And Salicylic Acids, Rahmiye Aydin, Ulviye Özer, Naciye Türkel
Turkish Journal of Chemistry
The dissociation constant of the catechol derivatives 4-nitrocatechol (NCAT), 2,3-dihydroxybenzoic acid (2,3-DHBA), 3,4-dihydroxybenzoic acid (3,4-DBHA), 3,4-dihydroxyhenylacetic acid (3,4-DPHA) and 3,4-dihydroxycinnamic acid (3,4-DHCA) were identified in 0.1M NaClO_4 ionic medium, at t=25^{\circ}C, by potentiometry. In addition, the first and second dissociation constants of the salicylic acid derivatives 5-nitrosalicylic acid (5-NSA), 4-hydroxysalicylic acid (4-HSA) 5-nitrosalicylic acid (5-HSA) were also determined by potentiometry. Furthermore, the second acid dissociation constants of these ligands were evaluated in I=0.1M NaClO_4 ionic medium, at a temperature of 25^{\circ}C by computer analysis of spectroscopic data.
Application Of The Residue Method To A Mixed Problem, Y. A. Mamedov, M. Can
Application Of The Residue Method To A Mixed Problem, Y. A. Mamedov, M. Can
Turkish Journal of Mathematics
In this paper, the residue method of separation of variables is applied to a mixed problem which includes the flow of a stratified compresslble fluid and inner gravitational waves of a stratified incompressible fluid for special values of the coefficients of the equation. To apply this method one defines two auxiliary problems. The first one is a spectral problem and the second is a Cauchy problem. Using the solutions of auxiliary problems, an existence and uniqueness theorem is proved for the given mixed problem.
Products And Quotients Of (P,\Sigma)-Absolutely Continuous Operator Ideals^*, Enrique A. Sanchez Perez
Products And Quotients Of (P,\Sigma)-Absolutely Continuous Operator Ideals^*, Enrique A. Sanchez Perez
Turkish Journal of Mathematics
We obtain a generalization of the ideal {\cal M}_{(q,p)} of (q,p)-mixing operators-in the sense of Pietsch- as a consequence of the study of the quotients of (p, \sigma)-absolutely continuous operator ideals {\cal P}_{p, \sigma} -in the sense of Jarchow and Matter-. Inclusions {\cal P}_{p, \sigma} (E,F) \subset {\cal M}_{(q,s)} (E,F) are also investigated, specially for the cases E={\cal C}(K) and E=L_1.
On Surjectivity Of The Arens Homomorphism, S. Alpay, B. Turan
On Surjectivity Of The Arens Homomorphism, S. Alpay, B. Turan
Turkish Journal of Mathematics
We define approximate separation and extension properties of a Banach lattice and study the relation between these and topological fullness of the ideal centre. Banach lattices with topologically full ideal centre are characterized as those for which the Arens homomorphism m: Z(E)''\rightarrow Z(E') is surjective. Among the positive operators T:E\rightarrow F between Banach lattices E,F we distinguish nearly Z(E) and Z(F) extremal ones and study their properties.
Certain Classes Of Analytic And Multivalent Functions With Negative Coefficients, M. K. Aouf, A. Shamandy, A.A. Attiyia
Certain Classes Of Analytic And Multivalent Functions With Negative Coefficients, M. K. Aouf, A. Shamandy, A.A. Attiyia
Turkish Journal of Mathematics
We introduce a subclass K^{*}_{n+p-1}(A,B) of analytic and p-valent functions with negative coefficients. Coefficient estimates, some properties, distortion theorems and closure theorems of functions belonging to the class K^{*}_{n+p-1}(A,B) are determined. Also we obtain radii of close-to-convexity, starlikeness and convexity for the class K^{*}_{n+p-1}(A,B). We also obtain class preserving integral operator of the form F(z)=\frac{c+p}{z^c}\int_0^{z}t^{c-1}f(t) dt, c> -p for the class K^{*}_{n+p-1}(A,B) Conversely when F(z)\,\, \in K_{n+p-1}^{\star} (A,B) radius of p-valence of f(z) defined by the above equation is obtained.
Weak Forms Of Openness Based Upon Denseness, C. W. Baker
Weak Forms Of Openness Based Upon Denseness, C. W. Baker
Turkish Journal of Mathematics
A function is defined to be hardly open provided that the inverse image of each dense subset of the codomain that is contained in a proper open set is dense in the domain. This form of weak openness is shown to be strictly between near feeble openness and somewhat openness. Characterizations and properties of hardly open functions are presented.
Suborbital Graphs For The Normalizer Of\Gamma_O(N), M. Akbaş, T. Başkan
Suborbital Graphs For The Normalizer Of\Gamma_O(N), M. Akbaş, T. Başkan
Turkish Journal of Mathematics
In this paper we examine some properties of suborbital graphs for the normalizer {\cal N} of \Gamma_{0}(N) in PSL(2,R) and show that, if {\cal N}/\Gamma_{0}(N) and the set of orbit representatives are denoted by B and \Omega respectively, the permutation group (B,\Omega) is regular and m-regular where m is an odd natural number.
On Homogeneous Riemann Boundary Value Problem, K. Kutlu
On Homogeneous Riemann Boundary Value Problem, K. Kutlu
Turkish Journal of Mathematics
In this work we consider homogeneous Riemann boundary value problem (BVP) on general open rectifiable curves. We prove certain estimates for Cauchy type integrals in terms of local moduli of continuity and local maximum of modulus, which allow us to describe the solvability of Riemann BVP with unbounded oscillating coefficients on a wide class of non-smooth rectifiable Jordan curves.
On Strongly Regular Rings, A. Kaya, F. Kuzucuoğlu
On Strongly Regular Rings, A. Kaya, F. Kuzucuoğlu
Turkish Journal of Mathematics
Some characterizations of strongly regular rings will be given. Let R be a ring and I(\neq R) a right ideal of R. If, for each pair of right ideals A and B of R, AB \subseteq I implies that either A \subseteq I or B \subseteq I, then I is called a prime right ideal (or equivalently, if aRb \ \ \not\subseteq I whenever a and b do not belong to I). I is strongly prime right ideal if, for each pair of a and b in R, aIb \subseteq I and ab \in I imply that either a \in …
Weak\Star- Invariantly Complemented Subspaces Of L^{\Infty}(1/\Omega) And Ideals Of L^{1}(\Omega) With A Bounded Approximate Identity, Z. Argün, C. Tonyali
Weak\Star- Invariantly Complemented Subspaces Of L^{\Infty}(1/\Omega) And Ideals Of L^{1}(\Omega) With A Bounded Approximate Identity, Z. Argün, C. Tonyali
Turkish Journal of Mathematics
For a locally compact group G let L^{1}(\omega) be the weighted group algebra and let X be a weak \star-closed translation invariant subspace of L^{\infty} (1/\omega). In this paper for a certain class of functions we show that the following conditions are equivalent: (i) X is topological invariantly complemented in L^{\infty}(1/\omega); (ii) X is invariantly complemented in L^{\infty}(1/\omega); (iii) The left ideal X_{\perp} has a bounded right approximate identity.
Extension Of Caristi-Kirk's Theorem, M. O. Diallo, M. Oudadess
Extension Of Caristi-Kirk's Theorem, M. O. Diallo, M. Oudadess
Turkish Journal of Mathematics
We give some extensions and/or improvements, to uniform spaces and to multi-valued mappings, of Caristi-Kirk's theorem.
Normal Boundary Value Problems For Differential Equations Of Higher Order, F. G. Maksudov, Z. I. Ismailov
Normal Boundary Value Problems For Differential Equations Of Higher Order, F. G. Maksudov, Z. I. Ismailov
Turkish Journal of Mathematics
In this work the arbitrary order differential operator expression of the form \imath (u) = \frac{\partial u (t)}{\partial t^n}+Au(t), where A is a bounded normal operator in the Hilbert Space H is considered in the Hilbert Space of vector functions L_2(H(0,1)). This paper describes all normal boundary value problem for the indicated diferential expression in terms of abstnract boundary conditions and determines a connection with other typea of boundary value problems.
T_2-Objects In Categories Of Filter And Local Filter Convergence Spaces, M. Baran
T_2-Objects In Categories Of Filter And Local Filter Convergence Spaces, M. Baran
Turkish Journal of Mathematics
There are various generalizations of the usual T_2 (Hausdorff) axiom of topology to an arbitrary topological category defined in [1]. In this paper, four more new generalizations of Hausdorff spaces are given in the topological categories. Moreover, the relationships among all of these T_2 structures and the ones given in [5] and [7] as well as some invariance properties of them are investigated in the categories of filter and local filter convergence spaces. Keywords: Topological Categories, T_2-objects, Filter Convergence Spaces.
On Conformally Flat Lorentzian Spaces Satisfying A Certain Condition On The Curvature Tensor, M. Erdoğan
On Conformally Flat Lorentzian Spaces Satisfying A Certain Condition On The Curvature Tensor, M. Erdoğan
Turkish Journal of Mathematics
In this paper we prove a local classification theorem for the conformally flat lorentzian spaces satisfying the condition R(X,Y)R=0.
On The Additive Group Structure Of Nonstandard Models Of Z, Ç. Gencer, M. Terzi̇ler
On The Additive Group Structure Of Nonstandard Models Of Z, Ç. Gencer, M. Terzi̇ler
Turkish Journal of Mathematics
Let \hat{Z} denote the inverse limit of finite cyclic groups and F_gZ the group where $F$ is a vector space over Q and + is defined by (a, x)+(b, y)=(a+b, x+y+g(a,b)) for some g: F\times F\rightarrow Z. In this paper we show that any nonstandard model Z^{\star} of Z is isomorphic to F_{\beta}Z for some \beta: F\rightarrow \hat{Z} where F=Z^{\star}/Z.
A Note On Double Sequences Of Fuzzy Numbers, E. Savaş
A Note On Double Sequences Of Fuzzy Numbers, E. Savaş
Turkish Journal of Mathematics
In this paper we introduce double convergent sequences of fuzzy numbers and we also study the space of double convergent sequences of fuzzy numbers.
Rings In Which Strongly Prime Right Ideals Are Finitely Generated, A. Kaya
Rings In Which Strongly Prime Right Ideals Are Finitely Generated, A. Kaya
Turkish Journal of Mathematics
Some properties of rings in which every strongly prime right ideal is finitely generated will be investigated, and sufficient conditions for such rings to be right noetherian will be given. Let R be an s-unital ring (i.e., a\in aR\cap Ra for each a\in R) and I(\neq R)a right ideal of R. If, for each right ideals A and B of R, AB\subseteq I implies that either A\subseteq I or B\subseteq I, then I is called a prime right ideal (or equivalently, if a\, R\,b \not\subseteq I whenever a and b do not belong to I). I is strongly prime if, …
A Property Of Meldrum Groups, A. O. Asar, S. Atlihan
A Property Of Meldrum Groups, A. O. Asar, S. Atlihan
Turkish Journal of Mathematics
In this work it is shown that the direct product of two Meldrum groups does not satisfy the normalizer condition. It is not known yet if the same result holds true for any two HM-groups.
The Group Structure Of Hecke Groups H(\Lambda_Q), İ. N. Cangül
The Group Structure Of Hecke Groups H(\Lambda_Q), İ. N. Cangül
Turkish Journal of Mathematics
In this work a new proof of the fact that the group structure of the Hecke groups is isomorphic to the free product of two cyclic groups of orders 2 and q is given The method used in the proof requires a result of A.M. Macbeath together with the notion of fundamental region. Also given are some new results on the parabolic points of Hecke groups, which still is an open problem.