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871.
Şükriye Güveli Namık Özdemir Tülay Bal-Demirci Bahri Ülküseven Muharrem Dinçer Ömer Andaç 《Polyhedron》2010
Reaction of 2-hydroxyacetophenone thiosemicarbazone with [Ni(PPh3)2Cl2] in optimized conditions afforded a mixed ligand complex with an isolated triphenylphosphine molecule. The structure was characterized by elemental analysis, IR, NMR and UV–Vis. spectroscopies and single crystal X-ray diffraction technique. In addition, the molecular geometry, vibrational frequencies and gauge including atomic orbital (GIAO) 1H and 13C NMR chemical shift values of the title compound in the ground state have been calculated using the density functional theory (DFT/B3LYP) method with the 6-31G(d,p) basis set for the C, N, O, S, P, H atoms and LANL2DZ pseudo-potential for the Ni atom, and compared with the experimental data. Besides, atomic charge distributions, molecular electrostatic potential and frontier molecular orbitals (FMO) analysis of the title compound were investigated by theoretical calculations. The thermodynamic properties of the compound at different temperatures have been calculated and corresponding relations between the properties and temperature have also been obtained. Atomic charge distributions indicate that during forming the title compound, the free ligand of thiosemicarbazone ion transfers their negative charges to central Ni(II) ion. The effect of different solvents (chloroform, methanol and water) on the geometry, vibrational frequencies, total energies and dipole moments was studied using the density functional theory (DFT/B3LYP) method by applying the Onsager and the Polarizable Continuum Model (PCM). 相似文献
872.
The regularity properties of a family of closed convex sets with nonempty intersection are investigated in the frame of a real Hilbert space. The significant role of these properties in solving convex feasibility problems with projection algorithms is pointed out. 相似文献
873.
We find an obstruction to the existence of non-singular solutions to the normalized Ricci flow on four-manifolds with b+ = 1. By using this obstruction, we study the relationship between the existence or non-existence of non-singular solutions
of the normalized Ricci flow and exotic smooth structures on the topological 4-manifolds , where .
Received: 13 November 2008 相似文献
874.
A sensitive and selective method of analysis was constructed by the the combination of praseodymium oxide and carbon nanotubes. The charge transfer resistance (Rct) values of 109 in 1 × 10−3 M K3[Fe(CN)6] and 79 Ω in 5 × 10−6 M dopamine indicate that Pr6O11@MWCNTs/GCE enables an excellent electron pathway between electrolyte and electrode. The platform was successfully applied for the determination of dopamine in the presence of tramadol, paracetamol and ascorbic acid. The platform exhibited a remarkable decrease in ▵Ep for DA. A dynamic linear range from 1.2 × 10−9 M to 1.8 × 10−5 M was obtained with an LOD of 1.0 × 10−10 M. Such a sensitive and selective method of analysis makes Pr6O11@MWCNTs/GCE of high interest to observe trace level of DA with good accuracy and precision. 相似文献
875.
Yılmazoğlu Mesut Bayıroğlu Fatih Erdemi Hamit Abaci Ufuk Guney H. Yuksel 《Journal of Solid State Electrochemistry》2023,27(5):1143-1154
Journal of Solid State Electrochemistry - In this study, polymeric membranes composed of ionic liquid (IL), 1-ethyl-3-methylimidazolium tetrafluoroborate supported sulfonated poly(ether ether... 相似文献