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31.
Jin J Sugiyama Y Mitsui K Arakawa H Ichinose I 《Chemical communications (Cambridge, England)》2008,(8):954-956
Nanomechanical properties of free-standing reversed surfactant bilayers, dried foam films (DFFs), were examined via AFM by fitting local force-indentation curves with a Hertzian model. The Young's moduli of four kinds of bilayers were in a range of 10-30 MPa. 相似文献
32.
Hirao I Mitsui T Kimoto M Yokoyama S 《Journal of the American Chemical Society》2007,129(50):15549-15555
Expansion of the genetic alphabet by an unnatural base pair system provides a powerful tool for modern biotechnology. As an alternative to previous unnatural base pairs, we have developed a new pair between 7-(2-thienyl)imidazo[4,5-b]pyridine (Ds) and 2-nitropyrrole (Pn), which functions in DNA amplification. Pn more selectively pairs with Ds in replication than another previously reported pairing partner, pyrrole-2-carbaldehyde (Pa). The nitro group of Pn efficiently prevented the mispairing with A. High efficiency and selectivity of the Ds-Pn pair in PCR amplification were achieved by using a substrate mixture of the gamma-amidotriphosphate of Ds and the usual triphosphates of Pn and the natural bases, with Vent DNA polymerase as a 3' to 5' exonuclease-proficient polymerase. After 20 cycles of PCR, the total mutation rate of the Ds-Pn site in an amplified DNA fragment was approximately 1%. PCR amplification of DNA fragments containing the unnatural Ds-Pn pair would be useful for expanded genetic systems in DNA-based biotechnology. 相似文献
33.
Mitsui K Saito H Yamamura R Fukaya H Hitotsuyanagi Y Takeya K 《Chemical & pharmaceutical bulletin》2007,55(10):1442-1447
Nine new triterpenoids, 1-9, were isolated from the cortex of Cedrela sinensis (Meliaceae), together with six known compounds, sapelin E acetate, grandifoliolenone, azadirone, bourjotinolone A, piscidinol A, and hispidol B. The structures of 1-9 were determined by the 2D NMR experiments, chemical methods, and X-ray crystallography. 相似文献
34.
Y. Yoda H. Igarashi X.W. Zhang Y. Imai T. Mitsui I. Koyama S. Kikuta 《Hyperfine Interactions》2000,126(1-4):435-441
Multiple nuclear resonant scattering from an 57FeBO3 single crystal has been observed in the three-beam case. A change of the lifetime and a modulation of the quantum beat were
observed in our study. The high brilliance of synchrotron radiation and the high perfection of the synthetic 57FeBO3 single crystal enabled us to observe such an effect.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
35.
Yutaka Yoshikawa Kazumasa Satake Takahisa Mitsui Hiroyuki Sasada 《Optics Communications》2001,190(1-6):173-178
Lax et al. [Phys. Rev. 11 (1975) 1365] discovered that a light beam in vacuum is not a transverse wave but does have a longitudinal field component. We investigate atomic and molecular electric dipole transitions induced by such a light beam, in particular, linearly polarized in a transverse plane. We derive the selection rules and the transition rates for various quantization axes using the paraxial approximation up to the first order of 1/kw, where k is the wave number and w is the transverse size of the light beam. The light beam is able to yield atomic spin polarization in the direction perpendicular to both the optical axis and the transverse electric field, and its magnitude is approximately 1/kw times that generated by a circularly polarized light wave with the similar intensity. 相似文献
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39.
Miyuki Hagiwara Hiroshi Mitsui Sueo Machi Tsutomu Kagiya 《Journal of polymer science. Part A, Polymer chemistry》1968,6(3):609-621
The γ-radiation-induced polymerization of ethylene with the use of liquid carbon dioxide as a solvent, was studied from the viewpoint of kinetics. The polymerization was carried out at conversions less than 10% under the pressure ranging from 100 to 400 kg./cm.2, dose rates 1.3 × 104?1.6 × 105 rad/hr., and temperatures of 20–90°C. The concentration of carbon dioxide varied up to 84.1 mole-%. The polymerization rate and the polymer molecular weight were observed to increase with reaction time. This observation, however, becomes less pronounced with increasing concentration of carbon dioxide and with rising temperature. The exponents of the pressure and the dose rate were determined to be 2.3 and 0.85 for the rate, and 2.0 and ?0.20 for the molecular weight, respectively. From the kinetic considerations for these results, the effect of carbon dioxide on the initiation and termination reaction in the polymerization was evaluated. 相似文献
40.