Browsing by Author "Demir D."

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    Reduction of [Cp*2Mo2O5] in aqueous medium: Structure and properties of a triangular mixed oxo-hydroxo-bridged product, [Cp*3Mo3(μ-O)2(μ-OH) 4](X)2 (X = CF3CO2 or CF 3SO3)
    (Wiley-VCH Verlag, 2006) Demirhan F.; Çaǧatay B.; Demir D.; Baya M.; Daran J.-C.; Poli R.
    The reduction of [Cp*2Mo2O5] with Zn in a MeOH/H2O solution acidified with either CF3COOH or CF3SO3H leads to the formation of the [Cp* 3Mo3(μ-O)2(μ-OH)4] 2+ ion as its trifluoroacetate or trifluoromethanesulfonate salt. The structure of the compound was confirmed by X-ray analyses. The anions establish hydrogen-bonding interactions with all four bridging OH groups. Density functional calculations afford bonding parameters in close agreement with the observed structure and indicate that the cluster is best described as a valence-delocalized Mo313+ species. The five metal electrons are distributed among an α-type (z2) orbital, which accounts for most of the metal-metal attraction, and two essentially metal-metal nonbonding e-type (xy) orbitals with a slight Mo(μ-O) π*-type contribution. Because of the C2 symmetry, the latter orbitals are not degenerate. The calculations show that the unpaired electron is located in a molecular orbital with equal contribution from two Mo atoms, in agreement with the experimental observation of coupling of the unpaired electron to two Mo atoms in the isotropic EPR spectrum. © Wiley-VCH Verlag GmbH & Co. KGaA, 2006.
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    Aqueous reduction of [Cp*2W2O5]: Characterization of the triangular clusters [Cp*3W 3O4(OH)2]2+ and [Cp* 3W3O6]+ - Comparison with molybdenum
    (Wiley-VCH Verlag, 2007) Dinoi C.; Sözen P.; Taban G.; Demir D.; Demirhan F.; Prikhodchenko P.; Gun J.; Lev O.; Daran J.-C.; Poli R.
    Zinc reduction of Cp*2W2O5 in an acidified water-methanol medium affords the green 3-electron trinuclear cluster [Cp*3W3O4(OH)2]2+, isolated and crystallographically characterized as the triflate salt, 1. Upon exposure to air, this complex is oxidized to a related 2-electron cluster, [Cp*3W3O6]+, which was crystallized and characterized in three different salts, 2-4. The 3-electron cluster exhibits a near-tetragonal frozen-glass EPR spectrum, and it shows evidence of coupling of the unpaired electron to only one of the three W atoms. The two-electron cluster is diamagnetic. An electrospray ionization MS n study revealed a stepwise expulsion of neutral [Cp*WO 2] units as the main fragmentation process. DFT calculations unveiled the intimate details of the electronic structures of these complexes and fully rationalized the structural and spectroscopic properties. © Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
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    Synthesis and characterization of a novel 3-amino-1,2,4-triazole lead(II) coordination polymer
    (TUBITAK, 2014) Sözerli S.E.; Özen A.; Kani I.; Demir D.
    A novel [Pb2(μ-atrz) 2(μ-CH3 COO)(CH 3 COO)]n (atrz = 3-amino-1,2,4-triazole) complex was synthesized and characterized by IR spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The molecularstructure shows that the complex is a coordination polymer in which there are 2 different lead(II) ions with coordination number of 5, Pb(2), and, with a coordination number of 4, Pb(1). Each atrz acts as a bridging ligand between 2 Pb(II) ions through the 2 adjacent nitrogen atoms of the triazole ring. The acetate anions show different types of coordination mode: one acts as a bridge by coordination of the same oxygen atom with Pb(II) ions and the other as a monodentate coordination by one of the oxygen atoms with Pb(2). © TÜBİTAK.
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    Outcomes of coronary artery bypass surgery in syrian refugees
    (E-Century Publishing Corporation, 2016) Demir D.; Abanoz M.; Tulay C.M.; Aydın M.S.; Kasapoğlu B.Ö.; Merdanoğlu M.; Altıparmak İ.H.; Gücü A.
    Background: In recent years, an increasing number of individuals have become refugees as a result of wars and domestic disturbance in their countries. The struggle for life of refugees under difficult conditions, increasing health problems, and insufficient Access to health services result in the loss of human lives. The aim of the present study was to present the outcomes of coronary artery bypass surgery in Syrian refugees. Methods: We performed emergency or elective bypass surgery to 53 Syrian refugees who ran away from civil war in Syria, between 2012 and 2014. The preoperative, intraoperative, and postoperative data of the patients were evaluated. Results: Of the patients, 18.9% sustained myocardial infarction, 34% had diabetes, 28.3% had COPD, and 52.8% were smokers. Two patients had emergency surgery and 51 patients had elective surgery. In the postoperative period, five patients (9.4%) were found to have atrial fibrillation. Cerebrovascular disease was observed at three patients (5.7%) in the postoperative period, and one patient had wound infection. A total of three patients (5.7%) died. Conclusion: The authors believe that under appropriate conditions, refugee patients should also receive therapy for chronic disorders in addition to emergency interventions. © 2016, E-Century Publishing Corporation. All rights reserved.