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31.
Erol Ertan Taylan Akdogan June L. Matthews Michael A. Kovash 《Few-Body Systems》2013,54(7-10):1339-1341
We report new measurements of the neutron–deuteron elastic scattering cross section at energies from 135 to 250 MeV and center-of-mass angles from 80? to 130?. Cross sections for neutron-proton elastic scattering were also measured with the same experimental setup for normalization purposes. Our nd cross section results are compared with predictions based on Faddeev calculations including three-nucleon forces, and with cross sections measured with charged particle and neutron beams at comparable energies. 相似文献
32.
The molecule crystallizes in a ketohydrazone tautomeric form. The tautomeric form is stabilized by a strong intramolecular hydrogen bond of 2.709(2) Å binding the 3-oxo to the nearest nitrogen atom in the azine chain. The compound crystallizes in the monoclinic space group P2l/c witha=7.0470(4),b=11.3090(9),c=16.2250(4) Å, =90.310(3)°, V=1293.0(1) Å3, Z=4,Dx=1.3576 g cm–3 and (Cu-K)=7.03 cm–1. The molecule is nearly planar not regarding the methyl group; the small deviations from planarity are indicative of intramolecular interactions between the phenylazo group and indandione group. Some of the bond lengths and angles found in the molecule are distorted due to resonance, -electron delocalization and strain. The relation between these chemical effects and structural results are discussed. 相似文献
33.
Aslantas M Tümer M Sahin E 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,71(1):263-268
The dimeric complex, [C20H20CuN2O2]2, has been prepared and characterized by thermal analysis, IR spectroscopy and single-crystal X-ray diffraction techniques. The Cu atom in the binuclear complex exists in a distorted square-pyramidal configuration, defined by three O atoms and two N atoms. The crystal structure is stabilized by intermolecular C-H...O hydrogen bonding interaction. The electrochemical property of the complex was investigated in CH2Cl2 by cyclic voltammetry at 100 mV s(-1) scan rate. 相似文献
34.
Fac‐bis(ethanolamine)orotatonickel(II), [Ni(HOr)(ea)2] and mer‐bis(ethanolamine)orotatocopper(II) dihydrate, [Cu(HOr)(ea)2]· 2H2O were synthesized and characterized by elemental analysis, FT‐IR, UV‐Vis Spectroscopy and thermal analysis. In addition, their solid‐state structures were determined by single crystal X‐ray diffraction studies. Both the fac‐[Ni(HOr)(ea)2] (1) and mer‐[Cu(HOr)(ea)2]·2H2O (2) complexes are isomorphous and crystallize in the triclinic space group . The Ni2+ and Cu2+ ions are coordinated by two neutral ea ligands and one orotate dianion in a distorted octahedral fashion. The ea ligand acts as a bidentate donor through the amine N and hydroxyl O atoms, while orotate dianion is coordinated through deprotonated N3 pyrimidine atom and carboxylate oxygen atom as a bidentate ligand. Thermal decompositions of the complexes are studied in over the range 20–600 °C on heating in a static air atmosphere. 相似文献
35.
Tuncay TuncÛ Musa Sar Rahmi Yagbasan Habibe Tezcan Ertan SÛahin 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o192-o193
Molecules of the title compound (alternative name p‐methoxybenzaldehyde 2‐pyridylhydrazone), C13H13N3O, adopt an E configuration about the azomethine C=N double bond. Molecules are almost planar, the dihedral angle between the pyridine and methoxyphenyl rings being only 6.19 (12)°. Pairwise N—H⃛N hydrogen bonds [R(8) in graph‐set notation] link centrosymmetrically related molecules into discrete pairs. 相似文献
36.
Ersan Altun Vasco Heredia Ertan Pamuklar Mauricio Zapparoli Richard C. Semelka 《Magnetic resonance imaging》2009,27(9):1198-1207
Purpose
To determine the feasibility of post-gadolinium three-dimensional gradient-echo (3D-GE) sequence for the evaluation of the pulmonary arterial vasculature in patients with suspected pulmonary embolism (PE) and in patients with a variety of other disease processes.Materials and Methods
Twenty-six consecutive patients (18 females, 8 males; mean age±S.D., 46.6±21.1 years) who underwent chest magnetic resonance imaging (MRI) including post-gadolinium 3D-GE sequence for the evaluation of PE (Group A, n=13) and a variety of other disease processes (Group B, n=13) were included in the study. Post-gadolinium 3D-GE MR sequences were retrospectively, independently and blindly evaluated by two reviewers for the image quality of pulmonary arterial vasculature, and findings of PE and other disease processes. Clinical and imaging follow-up data for all patients were obtained. Interobserver agreement was calculated by kappa statistics.Results
All central and lobar pulmonary arteries, 71.4–89.6% of segmental arteries and 46.7–52.7% of subsegmental arterial units in both groups were visualized with sufficient diagnostic image quality on post-gadolinium 3D-GE sequences. PE involving lobar and segmental arteries was diagnosed in two patients in each group. Other disease processes including pneumonia, lung nodules, superior vena cava stenosis, lung metastases, chronic lymphocytic leukemia and aortic aneurysm were detected in 10 of 26 patients. There was good to excellent interobserver agreement (0.73 to 1.00) for all findings.Conclusion
Post-gadolinium 3D-GE sequence may be an alternative technique for the visualization of central, lobar and segmental arteries, and may diagnose PE and other pathologies involving the chest in different patient populations. 相似文献37.
Süheyla
zbey Arzu Akba Gülgün Ayhan‐Kilcigil Rahmiye Ertan 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(9):o559-o561
In the molecule of the title compound, C26H21N3O5S, a new type of sulfonamide derivative with potential antibacterial activity, the flavone moiety is almost planar. The isoxazole and aminophenyl rings are also planar and make dihedral angles of 77.0 (2) and 81.4 (1)°, respectively, with the best plane of the flavone ring system. The crystal structure is stabilized by intra‐ and intermolecular hydrogen bonds. 相似文献
38.
The photon transmission method was used to study latex film formation from poly(vinyl acetate) (PVAc) particles induced by two different solvents. Films with the same latex content were prepared from PVAc particles and exposed to vapor of ethanol-water and acetone-water mixtures in various compositions. Transmitted photon intensities, Itr, from these films increased with increasing vapor exposure time. The increase in Itr is attributed to the increase in crossing density at the polymer-polymer junction. The Prager-Tirrell model was employed to obtain the back-and-forth frequency, nu, of the reptating polymer chain during film formation induced by solvent vapor. It was observed that the produced nu values increase as the solvent content is increased for both solvents. Abilities of both solvents to form films were interpreted with the solubility parameters of the solvents and the PVAc. 相似文献
39.
Ertan?Aksahin Vildan?Ustoglu UnalEmail author Mehmet?Tomak 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(11):265
An exciton in a spherical quantum dot is studied analytically within the effective mass approximation. A parabolic confinement under an electric field is considered. The linear and nonlinear optical absorption coefficients are calculated within the density matrix formalism. No assumptions are made about the strength of the confinement. It is shown how the competing mechanisms of the Coulomb interaction, the confinement and the applied static electric field affect the optical absorption. 相似文献
40.
A simple and efficient synthesis for the preparation of unusual charge‐separated pyridinium (thio)barbiturate zwitterion derivatives was achieved via a one‐pot reaction of (thio)barbituric acid derivatives and 2‐pyridinecarbaldehyde under solvent‐free condition and also in methanol under refluxing. The structure of the compounds was confirmed by 1H NMR, 13C NMR, FT‐IR, mass and X‐ray analysis. The mechanism of the formation is discussed. Instead, no related pyridinium zwitterion was afforded from the reaction between dimedone and 2‐pyridinecarbaldehyde under the same conditions and its xanthene derivative was obtained. 相似文献