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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 …
Synthesis And Characterisation Of Anhydrous Magnesium Phosphate Mg$_3$(Po$_4$)$_2$, A. Baykal, M. Kizilyalli, R. Kniep
Synthesis And Characterisation Of Anhydrous Magnesium Phosphate Mg$_3$(Po$_4$)$_2$, A. Baykal, M. Kizilyalli, R. Kniep
Turkish Journal of Chemistry
The synthesis and characterization of anhydorus Mg_3(PO$_4)_2 was investigated. Mg_3(PO$_4)_2 is reported to have similar structural arrangements with Co_3(PO_4)_2 and \gamma-Zn_3(PO_4)_2 compounds. The sample was prepared by a new technique which is the reaction of MgCl_2.6H_2O and Na_3PO_4.12H_2O solutions at pH=5.1, which was adjusted by adding concentrated H_3PO_4 to the reaction mixture and heating the precipitated product at 600^{\circ}C untill constant weight. The purity of the product was checked by X-ray powder diffraction, IR, density measurement, SEM and DTA analysis. The monoclinic unit cell dimensions of product are a=7.605 (2), b=8.233 (3), c=5.080 (1)A^{\circ} and \beta= 94.19^{\circ} (3), which was …
A Study Of The Thermodynamical Interactions Of Bisphenol-A Polycarbonate With Some Solvents By Gas Chromatography, Özlem Cankurtaran, Ferdane Yilmaz
A Study Of The Thermodynamical Interactions Of Bisphenol-A Polycarbonate With Some Solvents By Gas Chromatography, Özlem Cankurtaran, Ferdane Yilmaz
Turkish Journal of Chemistry
Retentin diagrams of polycarbonate for n-nonane, ethyl acetate and n-butyl acetate were obtained using inverse gas chromatography in the temperature range 80-240^{\circ}C. The specific retention volumes, V^{\circ}_{g} the Flory-Huggins interaction parmeters, \chi^{\infty}_{12}, interaction parameters, \chi^{\ast}_{12}, and effective exchange-energy parameters \bar{X}_{12} of the equation-of-state theory of polycarbonate for n-octane, n-nonane, n-decane, ethyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, tert-butyl acetate and isoamyl acetate were obtained in the temperature range 200-240^{\circ}C. The parameter \delta_2 was estimated to be 10.7 (cal/cm^3)^{1/2} at room temperature using the \chi^{\infty}_{12} extrapolated to room temperature. Keywords: Bisphenol-A polycarbonate, polymer-solvent interactions, inverse gas chromatography, solubility parameter.
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.
Exotic Structures And Adjunction Inequality, Selman Akbulut, Rostislav Matveyev
Exotic Structures And Adjunction Inequality, Selman Akbulut, Rostislav Matveyev
Turkish Journal of Mathematics
No abstract provided.
On Some Bounds For The Solutions Of The Semi-Discretized Time-Dependent Ginzburg-Landau Equations, Erhan Coşkun
On Some Bounds For The Solutions Of The Semi-Discretized Time-Dependent Ginzburg-Landau Equations, Erhan Coşkun
Turkish Journal of Mathematics
We study the two-dimensional system of Time-Dependent Ginzburg-Landau Equations (TDGL) for modeling a thin film of superconductor subject to a uniform magnetic field. We discretize the TDGL for the space variables using bond variables and staggered grid partitioning technique. By investigating the temporal evolution of semi-discrete Helmholtz enery functional and that of Semi-discretized TDGL, we provide bounds for some observable physical quantities of interest such as superelectron density, supercurrent density, charge density, electric field, and induced magnetic field.
Kirby Calculus In Manifolds With Boundary, Justin Roberts
Kirby Calculus In Manifolds With Boundary, Justin Roberts
Turkish Journal of Mathematics
Suppose there are two framed links in a compact, connected 3-manifold (possibly with boundary, or non-orientable) such that the associated 3-manifolds obtained by surgery are homeomorphic (relative to their common boundary, if there is one.) How are the links related? Kirby's theorem gives the answer when the manifold is S^3, and Fenn and Rourke extended it to the case of any closed orientable 3-manifold, or S^1 \tilde{\times} S^2. The purpose of this note is to give the answer in the general case, using only minor modifications of Kirby's original proof.
The Hardy -Littlewood-Sobolev Inequality For Non-Isotropic Riesz Potentials, İnan Çinar
The Hardy -Littlewood-Sobolev Inequality For Non-Isotropic Riesz Potentials, İnan Çinar
Turkish Journal of Mathematics
In this study the inequality of Hardy-Littlewood-Sobolev type are established for non-isotropic generalized Riesz potential depending on \lambda -distance. In this paper we establish analogues of the well known Hardy-Littlewood-Sobolev inequality (see[3]) for Riesz potentials with non-isotropic kernel depended on \lambda distance. Note that different problems for convolution type integrals with kernels, depending on \lambda-distance were considered in [1] and [2].
Pin-Structures On Surfaces And Quadratic Forms, A. Degtyarev, S. Finashin
Pin-Structures On Surfaces And Quadratic Forms, A. Degtyarev, S. Finashin
Turkish Journal of Mathematics
A correspondence between various Pin-type structures on a compact surface and quadratic (Iinear) forms on its homology is constructed. Sum of structures is defined and expressed in terms of these quadratic forms and in terms of Whitney sum of Spin structures.
Locally Finite Barely Transitive Permutation Group With Almost Nilpotent Point Stabilizers, Mahmut Kuzucuoğlu
Locally Finite Barely Transitive Permutation Group With Almost Nilpotent Point Stabilizers, Mahmut Kuzucuoğlu
Turkish Journal of Mathematics
We show that the groups mentioned in the title are solvable. Moreover, a point stabilizer H of the locally finite barely transitive group G is almost nilpotent, whenever the indices H : H \cap H^g (g \in G) have a finite upper bound.
About Some Normal Subgroups Of Hecke Groups, İsmail Naci Cangül
About Some Normal Subgroups Of Hecke Groups, İsmail Naci Cangül
Turkish Journal of Mathematics
In this work we study the suucture of some special normal subgroups of Hecke groups. Particwarly those of genus O and 1 are studied by means of the regwar map theory which has been a growing subject in recent years. As a nice application, we calcwate the total number of genus 1 normal subgroups for a given index.
Nv-P-Groups With Nilpotent Centralizers, Ali Osman Asar, Aynur Yalincaklioğlu
Nv-P-Groups With Nilpotent Centralizers, Ali Osman Asar, Aynur Yalincaklioğlu
Turkish Journal of Mathematics
In this work a sufficient condition is given for an NC-p-group to have an epimorphic image which is an NF-p-group.
An Application Of Monodromy Groupoid, Osman Mucuk
An Application Of Monodromy Groupoid, Osman Mucuk
Turkish Journal of Mathematics
The monodromy groupoid was first inlioduced by Pradines in [7] and developed by Mucuk in [6] In this paper we give an application of the monodromy groupoid.
Locally Topological Groupoids, Osman Mucuk
Locally Topological Groupoids, Osman Mucuk
Turkish Journal of Mathematics
The notion of Iocally topological groupoid was introduced by Aof and Brown in [2]. On the other hand in [6] by Mackenzie a topological groupoid MG, called monodromy groupoid, is constructed. In this paper we prove that this groupoid MG gives a Iocally topological groupoid.
The Spectra And Fine Spectra For P-Cesáro Operators, Cafer Coşkun
The Spectra And Fine Spectra For P-Cesáro Operators, Cafer Coşkun
Turkish Journal of Mathematics
In [6], Rhaly computed the spectrum of p-Cesaro operator on the Hilbert space l_2 = {x = (x_k): \Sigma_k IX_kl^2 < infinite}. In the present paper, we study the spectrum and fine spectrum for p-Cesáro operators acting on C_o, the space of null sequences.
Painlevé Analysis And Infinite Lie Symmetries Of The Complex Modified Korteweg-De Vries-Ii Equation, Abulgassim Ali Muhammad, Mehmet Can
Painlevé Analysis And Infinite Lie Symmetries Of The Complex Modified Korteweg-De Vries-Ii Equation, Abulgassim Ali Muhammad, Mehmet Can
Turkish Journal of Mathematics
The Painleve analysis developed by Weiss et al. [9] for nonlinear partial differential equations is applied to the CMKdV-II equation. It has been shown that this equation passes the Painleve test. By specializing the arbitrary functions that appear in the phi series expansions found in the test, one obtains a system of partial differential equations for the formally arbitrary data. For specific systems, and conjectured in general, these equations are integrable. The form of the resulting reduction enables the identification of integrable reductions of the original systems. Assuming u_i = \upsilon_i = 0, i >= 2 we obtain conditions to …
Augmented Graded Rings, Mashhoor Refai
Augmented Graded Rings, Mashhoor Refai
Turkish Journal of Mathematics
In this paper we study the augmented graded rings and give the ralationship between these rings and stronger properties of graded rings.
On The Theory Of A Certain Class Of Quadratic Pencils Of Matrices And Its Applications, G.Sh. Guseinov, G. Oturanç
On The Theory Of A Certain Class Of Quadratic Pencils Of Matrices And Its Applications, G.Sh. Guseinov, G. Oturanç
Turkish Journal of Mathematics
This paper is devoted to the study of the properties of eigenvalues and eigenvectors of quadratic pencil \lambda^2C - \lambdaR - J , where C is a positive diagonal matrix, R is an arbitrary real diagonal matrix, J is a ,, tridiagonal" real symmetric and positive matrix. The obtained results are then used to solve the corresponding system of differential equations with boundary and initial conditions. Kev Words: Quadratic pencijs, eigenvalues, eigenvectors.
Near Ultrafilters And Luc-Compactification Of Real Numbers, Mahmut Koçak
Near Ultrafilters And Luc-Compactification Of Real Numbers, Mahmut Koçak
Turkish Journal of Mathematics
In this work we will investigate some of the topological properties of the Luc compactification of real numbers R in terms of the concept of near ultrafilters.
On The Solution Of The E.P.D. Equation Using Finite Integral Transformations, Neşe Dernek
On The Solution Of The E.P.D. Equation Using Finite Integral Transformations, Neşe Dernek
Turkish Journal of Mathematics
In this paper, a solution is given for the following initial boundary value problem: \Delta=u_{tt}+k/t+u_t+g(x, t) (t>0) u(0, t)=u(a, t)=0 u(x, 0)=f(x), u_t(x, 0)=0 where x, a \epsilon R^n, t is the time variable, k < 1, k ? -1, -2, -3, . . . is a real parameter, \Delta is the n dimensional Laplace operator, f and g real analytic functions. The equation in this problem is known as the nonhomogeneous Euler-Poisson-Darboux (E.P.D.) Equation. The solution is obtained using finite integral transformation technique and is the sum of two uniformly and absolutely convergent power series.
Locally Nilpotent P-Groups Whose Proper Subgroups Are Nc-Groups, A.O. Asar, A. Yalincaklioğlu
Locally Nilpotent P-Groups Whose Proper Subgroups Are Nc-Groups, A.O. Asar, A. Yalincaklioğlu
Turkish Journal of Mathematics
Let G be a locally nilpotent p-group in which every proper subgroup is an NC-group. It is shown that G is itself an NC-group if either (i) the normal closure of every finite subgroup of G is a Chernikov extension of a CC-group or (ii) every proper normal subgroup of G is the union of an ascending chain of normal CCsubgroups.
Features Of Graft Copolymer Formation Through Reaction Of Functionalized Polyolefins With Poly-\Epsilon-Caprolactam, Elisa Passaglia, Francesco Picchioni, Mauro Aglietto, Giocomo Ruggeri, Francesco Ciardelli
Features Of Graft Copolymer Formation Through Reaction Of Functionalized Polyolefins With Poly-\Epsilon-Caprolactam, Elisa Passaglia, Francesco Picchioni, Mauro Aglietto, Giocomo Ruggeri, Francesco Ciardelli
Turkish Journal of Chemistry
The reaction in the melt of polyolefins containing 2-diethylsuccinate groups (DES) with poly-\epsilon-caprolactam (PA6) to give a graft copolymer was investigated under different conditions. Even using a large excess of DES groups over the PA6 terminal amino groups the graft copolymer yield resulted only partial thus suggesting a kinetic control of the reaction. The effect of various catalysts was then examined taking into account results obtained in a model reaction between a low molecular weight amine and diethylsuccinate. The results are discussed in terms of side reactions and miscibility of the pristine polymers.