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631.
Çiğdem Yüksektepe Nezihe Çalişkan Ibrahim Yilmaz Alaaddin Çukurovali 《Journal of chemical crystallography》2010,40(12):1049-1059
Abstract
A new compound of (C27H25N3S) has been synthesized and characterized by 1H NMR, 13C NMR, IR, UV-Visible spectroscopy, and single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c and crystals of (I) were found approximately 0.5:0.5 ratio to be twinned. The crystal structure is stabilized by N–H···N inter molecular hydrogen bonding. In addition to the molecular geometry and dimeric structure from X-ray experiment, the optimized molecular geometry for monomer and dimer, vibrational frequencies, atomic charges distribution, and total energies of the title compound in the ground state have been calculated using ab initio method. Density Functional Theory (B3LYP) and Hartree-Fock (HF) methods with basis sets 6-31G(d, p) and 3-21G were used in the calculations. Calculated frequencies are in good agreement with the corresponding experimental data. UV-Vis absorption spectra of the compound have been ascribed to their corresponding molecular structure and electrons orbital transitions. 相似文献632.
Giray Topal Nadir Demirel Mahmut Torul Yilmaz Turgut Halil Hogren 《Journal of heterocyclic chemistry》2001,38(1):281-284
This study represents a facile synthesis of building blocks ( 1–3 ) of crown ethers and amine precoursers ( 4a‐d ). The study also involves synthesis of mono and dibenzo N, N‐disubstituted diaza 18‐crown‐6 derivatives with high yield without chromatographic purification and high vacuum distillation. The complex ability of host the ethers was evaluated in terms of structural modification. 相似文献
633.
Nickel(II) complexes with three new vic‐dioxime reagents, N‐(ethyl‐4‐amino‐1‐piperidine carboxylate)phenylglyoxime (L1H2), N‐(ethyl‐4‐amino‐1‐piperidine carboxylate)glyoxime (L2H2) and N,N′‐bis(ethyl‐4‐amino‐1‐piperidine carboxylate)glyoxime (L3H2), have been prepared. Mononuclear nickel(II) complexes with a metal/ligand ratio of 1:2 were prepared using Ni(II) salt. All these nickel(II) complexes are nonelectrolytes as shown by their molar conductivities (ΛM) in DMF solution at 10−3 M concentration. The ligands are soluble in common solvents such as DMSO, DMF, CHCl3, and C2H5OH. The ligands and their Ni(II) complexes were characterized by elemental analyses, FT‐IR, UV‐visible, 1H NMR, 13C NMR, magnetic susceptibility measurements, cyclic voltammetry, and molar conductivities (ΛM). The cyclic voltammetric measurements show that [Ni(L1H)2] and [Ni(L2H)2] complexes exhibit almost similar electrochemical behavior, with two reduction and two oxidation processes based on either metals or oxime moities, while [Ni(L3H)2⋅2H2O] complex displays irreversible, with one reduction and one oxidation processes based on oxime moity. This main difference could be attributed to the highly polarized [Ni(L3H)2⋅2H2O] complex that has four carboxylate groups attached to piperidine on the oxime moieties. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:657–663, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20357 相似文献
634.
635.
We discuss the quasi-adiabatic approximations to the three-body wave-function in breakup processes and clarify the assumptions
underlying the model. This suggests alternative approximation schemes. Using different theoretical three-body models, calculated
angular distributions of differential cross sections for the 11Be(p,d) reaction are presented, for which new preliminary data have been reported at 35 MeV. We show that calculations are sensitive
to the inclusion of deuteron breakup and to the breakup model used, particularly if absolute spectroscopic information on
the 0+ and 2+
10Be core-state parentages is deduced. There is also considerable sensitivity to the model employed in calculations of the relative
cross sections of the two states.
Received January 19, 1999; revised April 16, 1999; accepted for publication February 28, 2000 相似文献
636.
O. Karabulut M. Parlak K. Yilmaz R. Turan B. G. Akinoglu 《Crystal Research and Technology》2003,38(12):1071-1076
GaSe single crystals grown by Bridgman method have been doped by ion implantation technique. The samples were bombarded in the direction parallel to c‐axis by Si ion beam of about 100 keV to doses of 1 × 1016 ions/cm2 at room temperature. The effects of Si implantation with annealing at 500 and 600 °C on the electrical properties have been studied by measuring the temperature dependent conductivity and photoconductivity under different illumination intensities in the temperature range of 100–320 K. It is observed that Si implantation increases the room temperature conductivity 10−7 to 10−3 (Ω‐cm)−1 depending on the post annealing temperature. The analysis of temperature dependent conductivity shows that at high temperature region above 200 K, the transport mechanism is dominated by thermal excitation in the doped and undoped GaSe samples. At lower temperatures, the conduction of carriers is dominated by variable range hopping mechanism in the implanted samples. Annealing of the samples at and above 600 °C weakens the temperature dependence of the conductivity and photoconductivity. This indicates that annealing of the implanted samples activates Si‐atoms and increases structural deformations and stacking faults. The same behavior was observed from photoconductivity measurements. Hence, photocurrent‐illumination intensity dependence in the implanted samples obeys the power low Ipc ∝ Φn with n between 1 and 2 which is an indication of continuous distribution of localized states in the band gap. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
637.
Trans‐bis(ethanolamine)bis(saccharinato)mercury(II), [Hg(ea)2(sac)2], where ea and sac denote the ethanolamine molecule and the saccharinate anion, respectively, crystallizes in the triclinic space group P (No. 2) with a = 9.4651 (5), b = 10.4365 (5), c = 11.9314 (6) Å, α = 84.402 (1)° β = 78.313 (1)°, γ = 75.307 (1)°, Z = 2, V = 1115.11 (10) Å3. The structure consists of isolated [Hg(ea)2(sac)2] units in which the Hg(II) ion is octahedrally coordinated by two nitrogen and two oxygen atoms of two neutral ea ligands, and two nitrogen atoms of two sac ligands. The ea acts as a bidentate N‐ and O‐donor ligand and occupies the trans positions of the equatorial plane of the coordination octahedron forming a fivemembered chelate ring, while sac behaves as a monodentate N‐donor ligand occupying the axial positions. The average Hg‐Nsac and Hg‐Nea bond distances are 2.739 (3) and 2.114 (7) Å, respectively. The crystal exhibits extensive hydrogen bonds between the hydroxyl and amine hydrogen atoms of the ea ligands and the sulfonyl, carbonyl and amine groups of the sac ligands. 相似文献
638.
Fatma Selampinar Ural Akbulut Tulay Yilmaz Attila Gungor Levent Toppare 《Journal of polymer science. Part A, Polymer chemistry》1997,35(14):3009-3016
A new electrically conducting composite film from polypyrrole and 4,4′-(hexafluoroisopropylidene)-bis(phthalic anhydride)-based polyimide was prepared. Pyrrole and the dopant ion can easily penetrate through the polyimide substrate and electropolymerize on the platinum (Pt) electrode due to the swelling of the polyimide on the metal electrode. The electrochemical properties of polypyrrole-polyimide (PPy/PI) composite films have been investigated by using cyclic voltammetry. The PPy/PI composite film is suitable for use as the electroactive material owing to its stable and controllable electrochemical properties. The electrical conductivity of composites falls in the range 0.0035–15 S/cm. Scanning electron micrograph, FTIR, and thermal studies indicate that PPy and PI form a homogeneous material rather than a simple mixture. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3009–3016, 1997 相似文献
639.
Tülay Yilmaz Hande Gülü
zdemir
zarslan Emel Yildiz Abdülkadir Kuyulu Ekrem Ekinci Attila Güngr 《Journal of polymer science. Part A, Polymer chemistry》1997,35(14):2981-2990
In this work, thermal solution imidization kinetics of two high performance polyimides, prepared from the polycondensation of pyromellitic dianhydride (PMDA) and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) with 4,4′-bis(3-aminophenoxy)diphenylsulfone (DAPDS) were investigated using nonaqueous titration technique with tetramethylammonium hydroxide. Most of the kinetic investigations, found in the literature, are based on the aromatic p-diamines.1,2 In the present work, attention was focused on imidization kinetics with m-substituted aromatic diamines having electron donating ( O ) and electron withdrawing ( SO2 ) groups in the same molecule. Kinetic parameters, namely the rate constants, activation energies, entropies and enthalpies of imidization reactions were determined and compared with the literature values. It is reported in literature3 that electron affinities of dianhydrides and ionization potentials of diamines, have strong influence on the reaction rate and activation energies of imidization. Activation energy (Ea) values were found to be 66 and 57 kJ/mol for DAPDS/PMDA and DAPDS/BTDA respectively, and order of reaction was found to be second order. Polyimides DAPDS/PMDA and DAPDS/BTDA, subjected to kinetic investigation, showed glass transition temperatures of 267°C and 241°C, both were found to be thermally stable up to 500°C. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2981–2990, 1997 相似文献
640.
In this study, Co doped TlGaS2 single crystals which belongs to the class of AIIIBIIIX2VI have been investigated by means of XRD, temperature dependent dark and illuminated conductivity, Space Charge Limited Currents and absorption measurements. The room temperature conductivity and trap concentration values were about 10‐8 (Ω‐cm)‐1 and 7.5 × 1013 cm‐3, respectively. From the temperature dependent conductivity measurements, two activation energies namely 271 and 12 meV have been determined in the high and low temperature regions, respectively. The trap level at 271 meV that was determined by the dark temperature dependent conductivity measurement has also been verified by Space Charge Limited Currents analysis. The absorption measurements have showed that the layered compound had indirect and direct band gaps and the values were determined to be 2.49 and 2.56 eV, respectively. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献