Yazar "Alp H." seçeneğine göre listele

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    Complexation of metal ions with double-armed diazadithia lariat ether carrying anthracene moieties in acetonitrile-dioxane
    (2010) Parlayan S.; Başo?lu A.; Göbel Y.; Ocak M.; Alp H.; Kantekin H.; Ocak Ü.
    A new 14-membered crown ether with nitrogen-sulfur donor atom carrying two anthryl groups 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 ligand was investigated in acetonitrile-dioxane solution (1/1) by means of absorption and emission spectrometry. The results of spectrophotometric titration experiments disclosed the complexation stoichiometry and complex stability constant of the novel ligand with Fe2+, Fe3+, Al3+, Cd2+, Cu2+, Zn2+, Pb2+ and Hg2+ cations. Absorption spectra show isobestic points in the spectrophotometric titration of these cations. The presence of excess of Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ cations caused an enhancement of anthryl fluorescence. Especially, the enhancement in case of the interaction of Hg2+ and Al3+ cations with the ligand was pronounced. © Springer Science+Business Media B.V. 2010.
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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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    Complexation of metal ions with the novel diazadithia crown ether carrying two anthryl pendants in acetonitrile-tetrahydrofuran
    (2010) Parlayan S.; Başo?lu A.; Ocak M.; Alp H.; Kantekin H.; Ocak Ü.
    A new crown ether carrying two anthryl groups with nitrogen-sulfur donor atom 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 ligand was investigated in acetonitrile-tetrahydofuran solution (1/1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Fe2+, Fe3+, Al3+, Cu2+ and Hg2+. The results of spectrophotometric titration experiments disclosed the complexation stoichiometry and complex stability constant of the novel ligand with Fe2+, Fe3+, Al3+, Cu2+and Hg2+cations. The presence of excess amounts of Al3+, Zn2+, Fe2+, Fe3+, Co2+, Ni2+, Mn2+, Cu2+, Cd2+, Hg2+ and Pb2+ cations caused an enhancement of anthryl fluorescence. The ligand showed good sensitivity for Zn2+ with respect to other metal cations with linear range and detection limit of 1. 4 × 10-7 to 4. 1 × 10-6 M and 1. 0 × 10-8 M respectively. © 2009 Springer Science+Business Media B.V.
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    Complexation of metal ions with the novel diazadithia crown ethers carrying two pyrene pendants in acetonitrile-tetrahydrofuran
    (2010) Ocak Ü.; Ocak M.; Başo?lu A.; Parlayan S.; Alp H.; Kantekin H.
    Two crown ethers carrying pyrene side arms with nitrogen-sulfur donor atom were designed and synthesized by the reaction of the corresponding macrocyclic compounds and 1-bromomethyl-pyrene. 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-tetrahydrofuran (1:1) by means of absorption and emission spectrometry. Absorption spectra show isosbestic points in the spectrophotometric titration of Al3+, Zn2+, Fe2+, Ni2+, Cu2+, and Pb2+ with 16-membered crown ether. Similar results were obtained for Al3+, Fe2+, Hg2+, Cu2+ and Pb2+ with 14-membered crown ether. The results of spectrophotometric titration experiments disclosed the complexation stoichiometry and complex stability constants of the novel ligands with these cations. According to spectrofluorimetric titration measurements the 14-membered diazadithia crown ether showed sensitivity for Pb2+ with linear range and detection limit of 1.3 × 10-6 to 5.2 × 10-5 M and 5.2 × 10-7 M, respectively. The 16-membered diazadithia crown ether showed sensitivity for Ni2+ with linear range and detection limit of 1.3 × 10-7 to 5.2 × 10-6 M and 4.1 × 10-8 M, respectively. © 2009 Springer Science+Business Media B.V.
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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.