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Microwave spectrum of monodeuterated diacetylene (HCCCCD), which is nonpolar in the equilibrium configuration, was observed in various excited states of bending vibrations. Dipole moments in the ν6, 2ν6, and ν6 + ν9 vibrational states were determined from the Stark effect measurement to be 0.0907(6), 0.1681(14), and 0.0900(4) D with uncertainties in parentheses, where ν6 and ν9 denote respectively the CCH bending and lowest frequency bending vibrations. The l-type doubling constant in the ν6 state is 2.1316(28) MHz. Rotational constants were determined in MHz; ν6(Π), 4086.2165(44); 2ν6(Δ), 4087.6963(58); ν6 + ν9(Δ), 4097.7537(50); 2ν8(Δ), 4094.4786(103); ν6 + ν7(Δ), 4092.9074(176); ν7 + ν8(Δ), 4095.8925(354); 2ν6 + ν9(Φ), 4098.9505(339).  相似文献   
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Transfer of solar radiation in the combined atmosphere and ocean system is evaluated by the matrix operator method. Derivation of the reflection and transmission matrices required for applying the matrix method is discussed introducing the shadowing effect of light by the ocean waves. Spectral and total radiation fields just above and below the ocean surface, as well as the top of the atmosphere, are numerically calculated using several optical models of the atmosphere, ocean, and wind roughened ocean surface. Dependencies of radiance and flux reflectivity on the wind velocity and optical property of the ocean body are discussed in detail.  相似文献   
999.
This Letter theoretically discusses quasiparticle states and nuclear spin relaxation rates T1-1 in the quasi-one-dimensional superconductor (TMTSF)2PF6 under a magnetic field applied parallel to the conduction chains. We study the effects of Josephson-type vortices on T1(-1) by solving the Bogoliubov-de Gennes equation for p-, d- or f-wave pairing interactions. In the presence of line nodes in pairing functions, T1(-1) is proportional to T in sufficiently low temperatures because quasiparticles induced by vortices at the Fermi energy relax spins. We also try to identify the pairing symmetry of (TMTSF)2PF6.  相似文献   
1000.
We investigated femtosecond and picosecond time-resolved fluorescence dynamics of a tetrameric fluorescent protein Kaede with a red chromophore (red Kaede) to examine a relationship between the excited-state dynamics and a quaternary structure of the fluorescent protein. Red Kaede was obtained by photoconversion from green Kaede that was cloned from a stony coral Trachyphyllia geoffroyi. In common with other typical fluorescent proteins, a chromophore of red Kaede has two protonation states, the neutral and the anionic forms in equilibrium. Time-resolved fluorescence measurements clarified that excitation of the neutral form gives the anionic excited state with a time constant of 13 ps at pH 7.5. This conversion process was attributed to fluorescence resonance energy transfer (FRET) from the photoexcited neutral form to the ground-state anionic form that is located in an adjacent subunit in the tetramer. The time-resolved fluorescence data measured at different pH revealed that excited-state proton transfer (ESPT) also occurs with a time constant of 300 ps and hence that the FRET and ESPT take place simultaneously in the fluorescent protein as competing processes. The ESPT rate in red Kaede was significantly slower than the rate in Aequorea GFP, which highly likely arises from the different hydrogen bond network around the chromophore.  相似文献   
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