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121.
Miyaji G Miyanaga N Urushihara S Suzuki K Matsuoka S Nakatsuka M Morimoto A Kobayashi T 《Optics letters》2002,27(9):725-727
In inertial confinement fusion research, uniform laser irradiation on a fusion target is a key issue. We propose a new method of beam smoothing in which we use three-directional spectral dispersion to reduce the coherent speckle that is unavoidable in the usual two-directional spectral-dispersion scheme. We have used this smoothing technique in a Nd:glass laser system and have demonstrated that the coherent speckle is reduced by a factor of 2.9 from that in two-directional spectral dispersion. 相似文献
122.
The reaction of 2,3-dichloro-5,6-dicyanopyrazine ( 1 ) with enamines as well as a few tertiary amines as enamine precursors was investigated. Both reactions gave aminovinyl-substituted pyrazine derivatives. During the attempted purification of 3c or 3d by column chromatography on silica gel, 2-chloro-5,6-dicyano-3-(1′-oxocyclopent-2′-yl)pyrazine ( 4 ) was obtained, apparently by hydrolytic cleavage. The products prepared are all of interest as potential pesticides. 相似文献
123.
Toshio Motojima Shun-Ichi Ikawa Masao Kimura 《Journal of Quantitative Spectroscopy & Radiative Transfer》1981,25(1):29-33
Infrared absorption intensities of the fundamental vibrations of liquid H2O have been obtained by measuring transmissions at two sample thicknesses (about 9 and 0.9 μ). The effect of multiple internal reflections on the observed absorptions is examined in terms of thin-film optics. It is shown that this simple method yields precise absorption intensities, without corrections for the effects of multiple internal reflections. The resulting intensities are 89.9 × 103 cm/mmol and 5.91 × 103 cm/mmol for the stretching and bending vibrations, respectively. The latter value was estimated after eliminating the absorption of intermolecular vibrations from the 1400–2400 cm-1 region by means of computer simulation. 相似文献
124.
The Ichikawa model with k = 2.0 (the Bennett model) for iron was relaxed using Johnson's potential and the potential by Pak and Doyama. The relaxed models reproduce the experimental pair-distribution function and structure sensitive intensity and have high packing fractions. 相似文献
125.
Masao Doi 《Journal of Polymer Science.Polymer Physics》1980,18(5):1005-1020
The primitive chain model of Doi and Edwards is generalized to include the short-time relaxation process. Stress relaxation after a sudden imposition of strain is studied in detail. It is shown that in the linear region (small strain) stress relaxation occurs in two steps, the relaxation of chain segments between the fixed entanglement points, and the relaxation of the entanglement points, in accordance with the conventional picture, whereas in the nonlinear region (large strain) there appears a new relaxation process between the above two. The characteristic time of this process is the Rouse relaxation time which the entire chain would have if there were no entanglements, and increases with the square of the molecular weight. This result is consistent with experimental observations. 相似文献
126.
Tsukasa Ikeda Ryoichi Kojin Chul-joong Yoon Hiroshi Ikeda Masao Iijima Kenjiro Hattori Fujio Toda 《Journal of inclusion phenomena and macrocyclic chemistry》1984,2(3-4):669-674
Cyclodextrin (CD) has a hydrophobic cavity which acts like a binding site of an actual enzyme. But enzymatic turnover reaction did not occur in CD-catalyzed reactions. -CD was modified by a histamine group to attach a reactive functional group. -CD-histamine accelerates the hydrolysis of p-nitrophenyl acetate. Catalytic rate constant of this reaction is close to an actual enzyme, -chymotrypsin. Enzymatic turnover reaction is realized with this compound at around neutral pH value. 相似文献
127.
Osamu Matsuoka 《Chemical physics letters》1981,77(2):387-389
Use of the grid points of the Gauss-Legendre numerical quadrature is examined as the exponent parameters of the basis functions of atomic Hartree-Fock wavefunctions. Calculations on He, Be, and Ne have been performed and reasonably accurate wavefunctions are obtained using 20 grid points or basis functions per symmetry species without any optimization of non-linear parameters. 相似文献
128.
The cw dye laser excitation spectrum of the vibronic band of HCCl was observed between 16 539 and 16 656 cm?1 with the Doppler-limited resolution, 0.03 cm?1. The HCCl molecule was generated by the reaction of discharged CF4 with CH3Cl. The observed spectra were assigned to c-type transitions with ΔKa = ±1 and also to axis-switching transitions with ΔKa = 0 or ?2, but all with K′a = 0, both for HC35Cl and HC37Cl. A rotational analysis yielded the rotational constants and quartic centrifugal distortion constants for the ground vibronic state and the band origin. A weak vibronic band, about one-third as intense as the main band, was found at about 57 cm?1 to the violet of the main band for both isotopic species, and was ascribed to a transition from the ground vibronic state to a vibrational level, possibly (041), of the à state. The rotational levels of HC35Cl in the à state showed a large perturbation; the J′ = 8, 9, and 10 levels were found to be split into two components. A normal coordinate analysis was carried out to calculate the centrifugal distortion constants and the inertia defect, which were in fair agreement with the observed values. The molecular structure of HCCl in the ground vibronic state was recalculated from the rotational constants of the two isotopic species combined with the 0.75B0 + 0.25C0 value previously reported for DC35Cl. 相似文献
129.
The title compounds and were synthesized by the usual dithia[3.3]phane coupling and photodesulfurization route. Investigation of their physical properties established their molecular dimension and conformation. Transannular interaction disclosed by their electronic spectra was explained by MO calculations. 相似文献
130.
Yoshihiro Takahashi Takashi Kitamura Kenji Uchida Masao Tomura 《Journal of luminescence》1980,21(3):269-275
Emission spectra and decay times of the fluorescence excited at the absorption edge region in pyrene crystals were measured. At liquid nitrogen temperature, the fluorescence under the excitation at 390 nm is considered as the excimer emission and its band peak shifts a little to the short wavelength in comparison with that of the excimer emission under the excitation at 360 nm. The emission decay times under the excitation at the 390 nm and 360 nm are about 155 ns and 180 ns, respectively, at liquid nitrogen temperature. The former decay time changes its value abruptly near 127 K. This abrupt change of the decay time may be due to the phase transition in pyrene crystals. 相似文献