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731.
In this paper, we introduce real lightlike hypersurfaces of indefinite
quaternion Kaehler manifold. Fundamental properties of real lightlike
hypersurfaces of an indefinite quaternion Kaehler manifold are
investigated. We prove the non existence of real lightlike hypersurfaces
in indefinite qaternionic space form under some conditions.
Received 31 October 2000; revised 20 June 2001. 相似文献
732.
Latif Kelebekli Yunus Kara Metin Balci Ertan ahin 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):o432-o434
In the title compound, C16H20Cl2O8, the bicyclic system contains a central non‐planar cyclohexane ring which is fused to a cyclobutane moiety. The cyclohexane ring has a chair conformation and the whole system adopts a syn conformation. The structure provides information on the stereochemical course of the chlorination, photo‐oxidation and hydroxylation steps of the reaction. 相似文献
733.
We have developed a new immunological biosensor for ultrasensitive quantification of human epidermal growth factor receptor-3(HER-3). In order to construct the biosensor, the gold electrode surface was layered with, hexanedithiol, gold nanoparticles, and cysteamine, respectively. Anti-HER-3 antibody was covalently attached to cysteamine by glutaraldehyde and used as a bioreceptor in a biosensor system for the first time by this study. Surface characterization was obtained by means of electrochemical impedance spectroscopy and voltammetry. The proposed biosensor showed a good analytical performance for the detection of HER-3 ranging from 0.2 to 1.4 pg mL−1. Kramers–Kronig transform was performed on the experimental impedance data. Moreover, in an immunosensor system, the single frequency impedance technique was firstly used for characterization of interaction between HER-3 and anti-HER-3. Finally the presented biosensor was applied to artificial serum samples spiked with HER-3. 相似文献
734.
735.
The structure of the title compound C11H7FN2O2S was characterized by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/n with Z = 12, i.e. with three molecules in asymmetric unit. The molecules are not planar: the dihedral angles between the planes of thiophene and the benzene rings are 42.3(3)°, 42.0(3)°, and 48.9(2)°. In the crystal, intermolecular C–H···F interactions link the molecules through R22 (14) ring motif. The crystal packing is also stabilized by π···π interactions. 相似文献
736.
M. Şerif Cansever Nevin Öztekin Ertuğrul Kıykım Tanyel Zübarioğlu Ayşe Çiğdem Aktuğlu Zeybek 《Journal of separation science》2023,46(16):2300145
2-hydroxyglutaric aciduria is an inherited neurometabolic disorder with two major types: D-2-hydroxyglutaric aciduria and L-2-hydroxyglutaric aciduria. An easy and fast capillary electrophoresis system combined with a capacitively coupled contactless conductivity detection method was developed for the enantioseparation and determination of D- and L-2-hydroxyglutaric acid in urine. D- and L-2-hydroxyglutaric acids were separated using vancomycin as the chiral selector. The optimal separation conditions for enantiomers were achieved by the use of a buffer containing 50 mM 4-(N-morpholino) butane sulfonic acid solution (pH 6.5), an electroosmotic flow modifier (0.001% [w/v] polybrene), and 30 mM vancomycin as chiral selector. The analysis time was 6 min under optimal conditions. The optimized and validated method was successfully implemented for quantifying D- and L-2-hydroxyglutaric aciduria in patients’ urine, without any pretreatment step. The linearity of the method was determined to be in the range of 2–100 mg/L for D- and L-2-hydroxyglutaric acid in urine. The precision (relative standard deviation%) was obtained at about 7%. For D- and L-2-hydroxyglutaric acids, the limits of detection were 0.567 and 0.497 mg/L, respectively. 相似文献
737.
JPC – Journal of Planar Chromatography – Modern TLC - Drawn by capillary forces the developing solvent (mobile phase) migrates through the thin layer (stationary phase) over a defined... 相似文献
738.
The mathematical model related to controlled potential experiments in electrochemistry is studied. Ion transport is regarded
as the superposition of diffusion and migration under the influence of an electric field. Modeling of the experiment leads
to the nonlocal identification problem for nonlinear parabolic equation. It is shown that in some cases the nonlocal identification
problem can be transformed to an initial value problem for nonlinear parabolic equation. The finite diference approximation
of this problem, with the appropriate iteration algorithm, is derived. Based on these algorithms the solution of the identification
problem is presented. The obtained results permits one to derive the behaviour of the current response , depending on time, also the relationship between the current response and Gottrellian is obtained in explicit form. An influence of the valences oxidised and reduced species is also analyzed.
相似文献
739.
Ahmet Karadağ İbrahim Önal Ayşegül Şenocak İbrahim Uçar Ahmet Bulut Orhan Büyükgüngör 《Polyhedron》2008
Two novel one-dimensional polymeric cyano-bridged platinum(II) complexes of N-(2-hydroxyethyl)-ethylenediamine (hydeten), [MII(hydeten)Pt(CN)2(μ-CN)2]n (MII = ZnII (1) and CdII (2)), were synthesized and characterized by physico-chemical methods (elemental analysis, IR spectroscopy and thermoanalytical measurements) and X-ray diffraction. Thermal behaviours of 1 and 2 were followed using TG and DTA (DSC) techniques. The 1D chain structures of 1 and 2 were verified by X-ray diffraction studies. According to the positions of the bridging cyano groups, in complex 1 the polymeric chains are built up via the 2,2-CT type, while in complex 2 the polymeric chains are built up via the 2,2-TT type. 相似文献
740.
Combined Hartree‐Fock‐Roothaan calculations have been performed using noninteger n Slater type orbitals for the ground states of the lowest electron configurations 1s22s22pn (2 ≤ n ≤ 6) for negative ions of B, C, N, O and F. These results are compared with the corresponding results obtained from the use of integer n Slater type orbitals. All of the nonlinear parameters are fully optimized. The results of calculation of coupling‐projection coefficients, orbital and total energies and virial ratios are presented. It is shown that the noninteger n Slater type orbitals, in general, improve the orbital energies. 相似文献