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51.
Alinur Büyükaksoy Ahmet Demir 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2005,56(4):694-717
A rigorous solution is presented for the problem of diffraction of plane harmonic sound waves by a cavity formed by a terminated rigid cylindrical waveguide of finite length whose interior surface is lined by an acoustically absorbent material. The solution is obtained by a modification of the Wiener-Hopf technique and involve an infinite series of unknowns, which are determined from an infinite system of linear algebraic equations. Numerical solution of this system is obtained for various values of the parameters of the problem and their effects on the diffraction phenomenon are shown graphically.Received: December 12, 2001 相似文献
52.
Aydan Dag Hakan Durmaz Emrah Demir Gurkan Hizal Umit Tunca 《Journal of polymer science. Part A, Polymer chemistry》2008,46(20):6969-6977
The double click reactions (Cu catalyzed Huisgen and Diels–Alder reactions) were used as a new strategy for the preparation of well‐defined heterograft copolymers in one‐pot technique. The synthetic strategy to the various stages of this work is outlined: (i) preparing random copolymers of styrene (St) and p‐chloromethylstyrene (CMS) (which is a functionalizable monomer) via nitroxide mediated radical polymerization (NMP); (ii) attachment of anthracene functionality to the preformed copolymer by the o‐etherification procedure and then conversion of the remaining ? CH2Cl into azide functionality; (iii) by using double click reactions in one‐pot technique, maleimide end‐functionalized poly(methyl methacrylate) (PMMA‐MI) via atom transfer radical polymerization (ATRP) of MMA and alkyne end‐functionalized poly (ethylene glycol) (PEG‐alkyne) were introduced onto the copolymer bearing pendant anthryl and azide moieties. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6969–6977, 2008 相似文献
53.
Cenap Özel Erol Yılmaz Hünkar Kayhan Aliekber Aktağ 《International Journal of Theoretical Physics》2008,47(12):3101-3107
In this paper, the entanglement properties of a system of two atoms inside an optical cavity in a stochastic interaction with
field are studied by the Jaynes-Cummings Model. The phase telegraph noise is considered as a noise term and an exact solution
to the model is obtained. The solution reveals the resulting decoherence effects of the noise on the entanglement properties
of the system. It shows that under the noise the individual atoms do not entangle with the cavity field. However, a strong
atom-atom entanglement is observed in a stationary state. It is seen that a relatively strong noise is cooperative in the
construction of the steady state atom-atom entanglement. 相似文献
54.
Selçuk Demir Hamide Merve Çepni Małgorzata Hołyńska Muammer Kavanoz Fatih Yilmaz Yunus Zorlu 《Journal of Coordination Chemistry》2017,70(19):3422-3433
Via an oxidation reaction of Cu(I) iodide with pyridine-2,6-dicarboxylic acid (H2L) in DMF three copper(II) complexes, [(CH3)2NH2]2[CuL2] (1), K2[CuL2]?H2L?H2O (2) and [Cu(L)(H2O)]n (3), were synthesized and characterized. The structures of 1–3 were determined by single crystal X-ray diffraction studies. In-situ DMF decomposition produces dimethylamine base under solvothermal conditions and a proton transfer reaction takes place for the complex formation of 1. 3-D networks are stabilized in 1 and 2 via hydrogen bonds. Complex 3 is a 1-D coordination polymer with Cu-O semi-coordination bonds. Thermal decomposition of the complexes results in the corresponding metal oxides. Also, the electrochemical behavior of 1 was determined to be a metal-centered and diffusion-controlled, one-electron reduction process. 相似文献
55.
Zeynep Ustaoglu Iyigundogdu Okan Demir Ayla Burcin Asutay Fikrettin Sahin 《Applied biochemistry and biotechnology》2017,181(3):1155-1166
In conjunction with an increasing public awareness of infectious diseases, the textile industry and scientists are developing hygienic fabrics by the addition of various antimicrobial and antiviral compounds. In the current study, sodium pentaborate pentahydrate and triclosan are applied to cotton fabrics in order to gain antimicrobial and antiviral properties for the first time. The antimicrobial activity of textiles treated with 3 % sodium pentaborate pentahydrate, 0.03 % triclosan, and 7 % Glucapon has been investigated against a broad range of microorganisms including bacteria, yeast, and fungi. Moreover, modified cotton fabrics were tested against adenovirus type 5 and poliovirus type 1. According to the test results, the modified textile goods attained very good antimicrobial and antiviral properties. Thus, the results of the present study clearly suggest that sodium pentaborate pentahydrate and triclosan solution-treated textiles can be considered in the development of antimicrobial and antiviral textile finishes. 相似文献
56.
Afsin Y. Cetinkaya Oguz Kaan Ozdemir Ahmet Demir Bestami Ozkaya 《Applied biochemistry and biotechnology》2017,182(2):468-481
Microbial fuel cells (MFCs) convert electrochemical energy into electrical energy immediately and have a big potential usage for the same time wastewater treatment and energy recovery via electro-active microorganisms. However, MFCs must be efficiently optimized due to its limitations such as high cost and low power production. Finding new materials to increase the cell performance and reduce cost for MFC anodes is mandatory. In the first step of this study, different inoculation sludges such as anaerobic gum industry wastewater, anaerobic brewery wastewater and anaerobic phosphate were tested, and MFC that was set up with anaerobic gum industry wastewater inoculation sludge exhibited the highest performance. In the second step of this study, various wastewaters such as chocolate industry, gum industry and slaughterhouse industry were investigated for anode bacteria sources. Several electrochemical techniques have been employed to elucidate how wastewaters affect the MFCs’ performance. Among all the mentioned wastewaters, the best performance was achieved by the MFCs fed with slaughterhouse wastewater; this device produced a maximum power density of 267 mW·m?2. 相似文献
57.
Erol Kurt 《Nonlinear dynamics》2006,45(1-2):171-182
A theoretical study is carried out on the dynamics of a magnetoelastic beam being in a step-pulsed magnetic field. For this
aim, the magnetic potential and elastic energies are determined for the beam and partial differential equations are established
according to Hamilton's principle. It is proven that the magnetoelastic beam can give a variety of complex behavior in the
case of step-pulsed field excitations. An intermediate regime of two-well chaos is observed. Theoretical findings were found
to be in a good agreement with the experimental results for the specific system parameters.
On leave from Institute of Physics, University of Bayreuth, 65440 Bayreuth, Germany
An erratum to this article is available at . 相似文献
58.
Ziprasidone is a psychotropic agent used for the treatment of schizophrenia. Its oxidation was investigated electrochemically at boron-doped diamond and glassy carbon electrodes using cyclic, differential pulse, and square wave voltammetry. The dependence of the peak current and peak potentials on pH, concentration, nature of the buffer, and scan rate were examined. The process was diffusion and adsorption controlled for boron-doped diamond and glassy carbon electrodes, respectively. The possible mechanism of oxidation was discussed with some model compounds that have indole and piperazine oxidations. A linear response was obtained between 8 × 10−7 and 8 × 10−5 M for the first peak in acetate buffer (pH 5.5) and between 2 × 10−6 and 2 × 10−4 M for the second peak in 0.1 M H2SO4 with boron-doped diamond electrode for differential pulse and square wave voltammetric techniques. The reproducibility and accuracy of the proposed methods were found between 0.31 and 1.20, 99.27 and 100.22, respectively. The recovery studies were also achieved to check selectivity and accuracy of the methods. The proposed methods were applied for the determination of ziprasidone from pharmaceutical dosage forms and human serum samples without any time-consuming extraction, separation, evaporation or adsorption steps prior to drug assay except precipitation of the proteins using acetonitrile. The results were statistically compared with those obtained through an established LC-UV technique, no significant differences were been found between the voltammetric and LC methods. 相似文献
59.
A simple extraction and determination method for folic acid (FA) in lentil samples was developed employing capillary electrophoresis. The analysis was performed in a 75 μm ID fused silica capillary using a running buffer of 10 mM sodium borate (10%, v/v, methanol, pH 9) at +18 kV and a detection wavelength at 200 nm. Methylparaben was used as the internal standard. FA signal response was linear in the range between 1.2 × 10?5 and 4.8 × 10?5 M. Limit of detection (inter-day) was determined at 6.12 × 10?7 M (3.3 σs?1). The amount of FA found in green, red and mignon lentils was found to range between 0.408 and 0.742 mg g?1. 相似文献
60.
Ümmühan Ocak Miraç Ocak Aysel Başoğlu Semanur Parlayan Dilek Başaran Hakan Alp Halit Kantekin 《Polyhedron》2010
A series of crown ethers carrying an anthracene group with nitrogen–sulfur donor atom, which differ in having three, four and five sulfur atoms in the macrocycle was designed and synthesized by the reaction of the corresponding macrocyclic compound and 9-chloromethyl-anthracene. The influence of metal cations such as Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ on the spectroscopic properties of the ligands was investigated in acetonitrile–dichloromethane (1:1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Al3+, Zn2+, Fe2+, Fe3+, Cu2+, Hg2+ and Pb2+ the results of which disclosed the complexation compositions and complex stability constants of the novel ligands with these cations. The monoazapentathia crown ether showed sensitivity for Al3+ with linear range and detection limit of 2.6 × 10−6 M–2.6 × 10−5 M and 8.1 × 10−7 M, respectively. 相似文献