Yazar "Ocak U." seçeneğine göre listele

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    Azathia crown ethers carrying pyrene pendant as receptor molecules for metal sensor systems
    (2011) Ocak U.; Ocak M.; Parlayan S.; Başo?lu A.; Ça?lar Y.; Bahadr Z.
    A series of crown ethers carrying a pyrene group with nitrogensulfur donor atoms, that 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 1-bromomethylpyrene. The influence of metal cations such as Mn 2+, Fe2+, Fe3+, Co2+, Ni 2+, Cu2+, Zn2+, Cd2+, Hg 2+, Pb2+ and Al3+ on the spectroscopic properties of the ligands was investigated in acetonitriledichloromethane (1:1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Fe2+, Zn2+, Cu2+, Pb2+ and Hg2+. The results of spectrophotometric titration experiments disclosed the complexation compositions and complex stability constants of the novel ligands with Fe 2+, Zn2+, Cu2+, Pb2+ and Hg 2+ cations. The monoazatetrathia crown ether showed good sensitivity for Cu2+ with linearity in the range 5.0×10-72. 5×10-6 M and detection limit of 1.6×10-8 M. © 2010 Elsevier B.V.
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    Complexation of metal ions with the novel azathia crown ethers carrying anthracene pendant in acetonitrile-dichloromethane
    (2010) Ocak U.; Ocak M.; Başo?lu A.; Parlayan S.; Başaran D.; Alp H.; Kantekin H.
    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. © 2009 Elsevier Ltd. All rights reserved.
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    Simple time-saving method for iron determination based on fluorescence quenching of an azaflavanon-3-ol compound
    (American Chemical Society, 2015) Başo?lu A.; Tosun G.; Ocak M.; Alp H.; Yayli N.; Ocak U.
    A simple and time-saving spectrofluorometric method developed using an azaflavanon-3-ol compound was used for the determination of iron in various food samples. Nitric acid and hydrogen peroxide were used for digestion of samples in a closed microwave system. The method was validated by analyzing two certified reference materials (CRM-SA-C Sandy Soil C and Mixed Polish Herbs INCT-MPH-2). Measurements were carried out using a modified standard addition method. The standard addition graph was linear until 21.6 mg/L in the determination of iron(III). Detection and quantification limits were 0.81 and 2.4 mg/L, respectively. Satisfactory accuracy was obtained for spinach, dill, mint, purslane, rocket, red lentils, dry beans, and two iron medicinal tablets. High recoveries were found for streamwater samples fortified at three different concentrations. The method is simple, time-saving, cost-effective, and suitable for the determination of the iron content of foods. © 2015 American Chemical Society.
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    Synthesis, characterization and complexation properties of a novel Mg-porphyrazine with metal ions in acetonitrile-chloroform
    (IOS Press, 2015) Kabay N.; Baygu Y.; Gök Y.; Başo?lu A.; Ocak U.
    The synthesis and characterization of a novel metal derivative of a peripherally symmetrically tetra-substituted porphyrazine derived from 25,26-dioxa-6,7,9,10,15,16,18,19-octahydro-25H-1,24-methanodibenzo[q,t][1,4,13,16,17,10]tetraoxadithiacyclohenicosine-12,13-dicarbonitrile was carried out. The influence of metal cations such as Zn2+, Fe2+, Mn2+, Ni2+, Co2+, Hg2+ and Cu2+ on the spectroscopic properties of the ligands, the starting material dinitrile and MgPz were investigated in acetonitrile-chloroform solution (1/1) by means of absorption spectrometry. Absorption spectra showed isosbestic points in the spectrophotometric titration of Cu2+ and Hg2+ with MgPz ligand. The results of spectrophotometric titration experiments disclosed the complex stability constant of the novel ligand, MgPz with Cu2+ and Hg2+ cations.