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Article Citation - WoS: 4Citation - Scopus: 3The Euler-Lagrange Theory for Schur's Algorithm: Wall Pairs(Academic Press inc Elsevier Science, 2006) Khrushchev, SThis paper develops a techniques of Wall pairs for the study of periodic exposed quadratic irrationalities in the unit ball of the Hardy algebra. (C) 2005 Elsevier Inc. All rights reserved.Article Citation - WoS: 14Citation - Scopus: 15Yielding of Two-Layer Shrink-Fitted Composite Tubes Subject To Radial Pressure(Springer Heidelberg, 2005) Eraslan, AN; Akis, TYielding of two-layer shrink-fitted composite tubes with axially constrained ends subject to either internal or external pressure is investigated in detail. In the framework of small deformations, a state of plane strain and von Mises yield criterion, analytical expressions are obtained for critical values of the pressure leading to plastic flow. It is shown that, depending on material properties and tube dimensions, different modes of plastic deformation may occur. Yielding may commence at the inner tube or at the outer tube or simultaneously in both tubes. The conditions for different nature of plastic flow are determined. Using analytical expressions obtained for critical values of the parameters and properties of real engineering materials, various numerical examples are handled and the variation of elastic limit pressure with interference and interface radius is explained.Article Citation - WoS: 5Citation - Scopus: 6Synthesis, X-Ray Data, and Hall Effect Measurements of Li-Doped Tl-Ba Superconductor(Wiley-v C H verlag Gmbh, 2003) Kayed, TSLithium-doped Tl-based superconductor was prepared by adding an amount of 0.3 mol.% to the Tl1.8Ba2Ca2.2Cu3Ox compound. The usual solid-state reaction method has been applied under optimum conditions. The x-ray data of the sample show a tetragonal structure with a high ratio of Tl-2223 superconducting phase. The sample showed a transition at 125 K and the zero resistance was observed at 117 K. Longitudinal (transport) and transverse (Hall) resistivities were measured at different temperatures under different magnetic fields and the data were interpreted. A positive Hall coefficient was observed at normal state and a sign reversal appears at temperatures lower than the critical temperature. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Article Citation - WoS: 2On Radical Field Extensions of Prime Exponent(World Scientific Publ Co Pte Ltd, 2002) Albu, TomaIn this paper we investigate finite separable radical extensions K subset of L of prime exponent via the concept of G-Cogalois extension. As particular cases we retrieve some older results in I. Kaplansky [9] and A. Baker and H. M. Stark [7] concerning such radical extensions.Article Citation - WoS: 28Citation - Scopus: 28Photoelectronic and Electrical Properties of Cuin5s8< Single Crystals(Wiley-v C H verlag Gmbh, 2003) Qasrawi, AF; Gasanly, NMTo identify the impurity levels in CuIn5S8 single crystals, the dark electrical conductivity and photoconductivity measurements were carried out in the temperature range of 50-460 K. The data reflect the intrinsic and extrinsic nature of the crystals above and below 300 K, respectively. Energy band gaps of 1.35 and 1.31 eV at 0 K and 300 K, were defined from the dark conductivity measurements and the photocurrent spectra, respectively. The dark and photoconductivity data in the extrinsic temperature region reflect the existence of two independent donor energy levels located at 130 and 16 meV. The photocurrent-illumination intensity dependence (F) follows the law I(ph)alphaF(gamma), with gamma being 1.0, 0.5 and 1.0 at low, moderate and high intensities indicating the domination of monomolecular, bimolecular and strong recombination at the surface, respectively. In the intrinsic region and in the temperature region where the shallow donor energy level 16 meV is dominant, the free electron life time, tau(n), is found to be constant with increasing F. In the temperature region 140 K < T < 210 K, the free electron life time increases with increasing illumination intensity showing the supralinear character. Below 140 K, tau(n) decrease with decreasing illumination intensity. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Article Citation - WoS: 5Citation - Scopus: 7Comparison of Nat1, Nat2 & Gstt2-2 Activities in Normal and Neoplastic Human Breast Tissues(Aepress Sro, 2006) Geylan-SU, YS; Isgör, B; Coban, T; Kapucuoglu, N; Aydintug, S; Iscan, M; Güray, T; Chemical EngineeringIn this study, arylamine N-acetyltransferases, NATs (E.C.2.3.1.5) and glutathione-S-transferase-T2-2, GSTT2-2 (E.C.2.5.1.18) enzyme activities in the breast tumor and surrounding tumor-free tissues of 22 female breast cancer patients with infiltrating ductal carcinoma were measured. The possible impacts of grade of malignancy, chemotherapy treatment, estrogen receptor status and menopausal status on all enzyme activities were evaluated. The results showed that, both NAT2 and GSTT2-2 display significant differences between tumor and tumor-free breast tissues, while no difference was observed in NAT1. Grade of malignancy seems to be positively associated with NAT1 and negatively associated with GSTT2-2. Though, both NAT2 and GSTT2-2 have increased mean tumor activities, the grade of malignancy, chemotherapy status, menopausal status or estrogen receptor status are not correlated statistically.Article Citation - WoS: 5Citation - Scopus: 5Electrochemical Polymerization of Para-Substituted Haloanilines(Taylor & Francis inc, 2006) Cihaner, A; Önal, AMPolyhaloanilines: poly(4-fluoroaniline) (P4FAN), poly(4-chloroaniline) (P4CAN), and poly(4-bromoaniline) (P4BAN), are synthesized from para-substituted haloaniline monomers; 4-fluoroaniline (4FAN), 4-chloroaniline (4CAN), and 4-bromoaniline (4BAN), respectively, via constant potential electrolysis (CPE) in acetonitrile-water mixture (1:1 v/v) with NaClO4 as supporting electrolyte. Prior to CPE, electrochemical behavior of the monomers were investigated in organic medium utilizing cyclic voltammetry (CV). The course of CPE was monitored using in-situ UV-VIS spectroscopic technique. Characterization of polymer products have been carried out using FT-IR and NMR spectroscopic techniques and thermal behaviors were studied using differential scanning calorimeter (DSC). Polyhaloanilines synthesized by electrochemical oxidation were doped using iodine and the change in the paramagnetic behavior was monitored by ESR, UV-VIS, and FT-IR.Article Citation - WoS: 6Citation - Scopus: 4Some results related to the Laplacian on vector fields(Kossuth Lajos Tudomanyegyetem, 2006) Erkekoglu, Fazilet; Kupeli, Demir N.; Uebnal, BuelentA characterization of Euclidean spheres out of connected, compact, Einstein Riemannian manifolds of constant scalar curvature is made by a characterization of a vector field with an eigenvalue equation for the Laplacian on vector fields.Article Citation - WoS: 1Citation - Scopus: 3Multivariable Nonlinear Model Reference Control of Cement Mills(Arnold, Hodder Headline Plc, 2003) Efe, MÖ; Department of Electrical & Electronics EngineeringThis paper presents a method for model reference control of a cement milling circuit that has previously been studied several times. The approach presented is based on an experimentally justified model of a cement milling circuit. We derive the form of the control vector with the goal of driving the response of the system to that of a desired model in a noisy operating environment. The paper demonstrates the selection of the reference dynamics and the derivation of the control laws. The approach is based on the Lyapunov theory, and the results observed justify the tracking and stability claims of the paper.Article A boundary value problem for second-order nonlinear difference equations on the integers(Cambridge Univ Press, 2005) Dal, F; Guseinov, GSIn this study, we are concerned with a boundary value problem (BVP) for nonlinear difference equations on the set of all integers Z, under the assumption that the left-hand side is a second-order linear difference expression which belongs to the so-called Weyl-Hamburger limit-circle case. The BVP is considered in the Hilbert space l(2) and includes boundary conditions at infinity. Existence and uniqueness results for solution of the considered BVP are established.
