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91.
Substantial improvement of the self-consistent HMO theory, as recently developed by one of us, is made in the parametrization for heterobonds. The theory is extensively applied to a large scale of heteroconjugated molecules including rather complicated ones which are biologically important. The calculated molecular geometries and the wavelengths of optical absorption spectra are found to be in good agreement with experimental values. Examining the effect of inclusion of the -technique to this theory, we find that the calculated values of molecular geometries, electronic spectra and ionization potentials are little affected for most molecules. Dependences of the absorption wavelength and the adiabatic potential on the molecular geometry are also investigated. 相似文献
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Ohne Zusammenfassung 相似文献
94.
Asymmetric hydrolysis of the acetates of racemic alkynyl alcohols and α-hydroxy esters by Bacillus subtilis var. Niger afforded optically active acetates and alcohols in 7–90% optical purities. The both enantiomers of optically pure mandelie acid were prepared by this microbial method. 相似文献
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Tomoya Ito Koji Suda Takuya Kumamoto Waka Nakanishi Toshiko Watanabe Tsutomu Ishikawa Hiroko Seki Masatoshi Kawahata Kentaro Yamaguchi Yasumitsu Ogura Kazuo T. Suzuki 《Molecular diversity》2010,14(1):131-145
The role of o-bisguanidinobenzenes (BGBs) as new Brønsted base ligands for arsenic and phosphoric acids was examined. In solution state, complexation was evaluated by Job’s plot in 1H NMR experiment, indicating a 1:1 complex formation, whereas in solid state crystalline structures of complexes obtained were addressed by X-ray crystallographic analysis and/or solid state 13C NMR experiment, in which 1:2 complexes between the BGB and the acid components were normally formed. Based on these results, Merrifield and Hypogel® resin-anchored BGBs were designed and prepared as the corresponding polymer-supported host ligands. Evaluation of their coordination ability with metal salts (ZnCl2 and CoCl2) and arsenic acid in aqueous media by ICP-MS showed that the latter Hypogel® resin-anchored BGBs acted as effective immobilized base ligands. 相似文献
98.
Three allylbenzenes from Asiasarum heterotropoides, methyleugenol (1), elemicin (2) and gamma-asaron (3) showed suppressive effects on umu gene expression of the SOS response in the Salmonella typhimurium OY1001/1A2 umu test against the mutagen 2-amino-3,4-dimethylimidazo[4,5-f ]quinoline (MeIQ). Gene expression was suppressed 70.0, 75.9 and 81.7% at a concentration of 0.4 mM, respectively. The ID50 values (50% inhibition dose) of these compounds were 0.125, 0.098 and 0.059 mM, respectively. On the other hand, compounds 1-3 showed weak suppressive effects of the SOS-inducing activity on activated MeIQ. 相似文献
99.
Fluorescence excitation, multiphoton ionization, and dispersed fluorescence spectra of bare and hydrogen-bonded 2-fluoropyridine with water were measured in a supersonic free jet. For bare 2-fluoropyridine, fluorescence quantum yield decrease in the higher vibronic levels was observed even under collision-free conditions. The inter-system crossing channel was probed experimentally by two color R2PI and found to be negligible. The non-radiative relaxation process of 2-fluoropyridine is mainly governed by the relaxation to the electronic ground state. Electronic spectra of 2-fluoropyridine-(water)(n) (n=1 approximately 3) were also obtained. The hydrogen bond formation with water increases the quantum yield in the higher vibronic levels. Rather low frequency vibrations were observed in the hole burning spectrum of bare 2-fluoropyridine; however, these vibronic bands disappeared with the hydrogen bond formation with water. The appearance of low frequency vibronic bands observed for bare 2-fluoropyridine is ascribed to the existence of closely lying (n,pi) state. 相似文献
100.
We analyze symmetry properties of the three-dimensional magnetization distribution in the optic-magneto film induced by focused circularly polarized lights. The magnetization distributions are derived and evaluated based on the vector diffraction theory and the inverse Faraday effect of the isotropic and nonmagnetically ordered material. It is shown that for any radial symmetrical amplitude, phase, or hybrid amplitude-phase pupil filter, the magnetization distribution of the axial component is circular symmetric but those of the radial and azimuthal components are annular symmetric with regard to the optical axis. All of the three components have a symmetric distribution with regard to the focal plane. The direction of both axial and radial components can be inversed with the helicity of incident circularly polarized light but the direction of azimuthal component is independent of helicity. The axial component has a decisive effect to all-optical magnetic recording, and within the effective axial range, the size of its magnetization domain hardly expands in the transverse direction. 相似文献