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61.
Hasan budak Ahmet Bulut Naziye etin Canan Kazak 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(1):m1-m3
The crystal structure of the first acesulfame–metal complex, namely tetraaquabis[6‐methyl‐1,2,3‐oxathiazin‐4(3H)‐onato 2,2‐dioxide‐κN]cobalt(II), [Co(C4H4NO4S)2(H2O)4], is reported. The CoII ion resides on a twofold axis and is coordinated by four aqua ligands defining the basal plane and by two monodentate acesulfamate ligands, via their ring N atoms, in the axial positions. Two intra‐ and three intermolecular hydrogen‐bonding interactions stabilize the crystal structure and form an infinite three‐dimensional lattice. 相似文献
62.
Phthalocyanines with four naphthyl-malonic ester groups on the periphery were synthesized by cyclotetramerization of 4-(1,1-dicarbethoxy-2-(1-naphthyl)-ethyl)-phthalonitrile.
The new compounds were characterized by spectroscopic methods. The electronic spectra exhibit intense π–π* transitions from
the naphthyl moiety together with the characteristic Q and B bands of the phthalocyanine core. The electrochemical properties
of the 2,9,17,23-tetra-(1,1-(dicarbethoxy)-2-(1-naphthyl)-ethyl) phthalocyaninato copper(II) complex were studied by cyclic
voltammetry. 相似文献
63.
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
64.
Ahmet ?ener Nurettin Menge? Mehmet Akkurt Orhan Büyükgüngör 《Tetrahedron letters》2008,49(17):2828-2831
Oxalacetic acid and pyruvic acid derivatives have been synthesized efficiently in high yields by the treatment of 4-ethoxycarbonyl-5-phenyl-2,3-furandione and 4-benzoyl-5-phenyl-2,3-furandione with 2-phenylindole at room temperature and converted to simple derivatives such as an ester or a hydrazone. 相似文献
65.
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
66.
In the present work, 4-(4′-dodecyloxycarbonyl) phenoxy phthalonitrile was synthesized and then this phthalonitrile derivative was cyclotetramerized in dodecanol resulting a new metal-free phthalocyanine. The optical properties of this phthalocyanine were investigated. Novel metal-free phthalocyanine thin films were deposited on indium tin oxide-coated glass substrates by spinning method. Surface and microstructural properties of the films were characterized by atomic force microscopy and scanning electron microscopy. Both the transmittance and reflectance spectra of the deposited films were recorded using an NKD analyser. The optical band gap energy, the thickness of thin films, refractive index (n) and extinction coefficient (k) were calculated as 2.7 eV, 300 nm, 1.47 and 0.02, respectively. 相似文献
67.
Ahmet Kilic Feyyaz Durap Akin Baysal Mustafa Durgun 《Journal of inclusion phenomena and macrocyclic chemistry》2010,68(3-4):423-429
1,3- and 1,2-calix[4]crown-7 and calix[4]crown-9 cone conformers were synthesized in acceptable yields by sequential introduction of two distal or proximal polyethylene glycolic chains with terminal hydroxyls at the lower rim, monotosylation, and intramolecular ring closure reaction. According to the two-phase extraction experiment, the title compounds showed mediocre affinity for alkali and alkaline earth metal picrates. The 1,2-calix[4]crown-9 extracted Sr2+ selectively among other alkaline earth metal cations. 相似文献
68.
It has long been known that thiol-terminated molecules self-assemble as commensurate monolayers on Au(111) surfaces. By spreading floating octadecanethiol monolayers on aqueous solutions of chloroauric acid (HAuCl4) and using x rays to reduce the gold ions as well as to probe the structure, we have observed the nucleation of (111)-oriented Au nanoparticles at thiol surfaces. This process may be similar to the formation of biogenic gold by bacteria. The thiol monolayer acts as a "soft template," changing its structure as Au crystals form so that there is a sqrt[3]×sqrt[3] commensurate relationship. 相似文献
69.
In this study,by means of homotopy perturbation method(HPM) an approximate solution of the magnetohydrodynamic(MHD) boundary layer flow is obtained.The main feature of the HPM is that it deforms a difficult problem into a set of problems which are easier to solve.HPM produces analytical expressions for the solution to nonlinear differential equations.The obtained analytic solution is in the form of an infinite power series.In this work,the analytical solution obtained by using only two terms from HPM soluti... 相似文献
70.
We study the variational problem belonging to a relaxed hyperelastic curve for non-null curve on a non-degenerate surface in Minkowski three-space \({E_{1}^{3}}\) . Firstly, we derive the intrinsic equations for a relaxed hyperelastic curve and we give the necessary condition for being relaxed hyperelastic curve of any non-null geodesic on the surface in \({E_{1}^{3}}\) . Then, we examine this formulation on non-null geodesics of pseudo-plane, pseudo-sphere \({S_{1}^{2}(r) }\) , hyperbolic space \({H_{0}^{2}(r)}\) and pseudo-cylinder \({C_{1}^{2}(r)}\) . 相似文献