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591.
Patellamides B and C, cytotoxic lipophilic cyclic peptides from a marine tunicate, with proposed structures have been synthesized by the use of diphenyl phosphorazidate(DPPA) and diethyl phosphorocyanidate(DEPC). Their physicochemical properties lead to reassign the structures of patellamides B and C on the bonding order. 相似文献
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593.
Y. Fujii H. Hamada K. Takahashi Y. Yamamoto T. Shigematsu M. Nakamura M. Yamaguchi T. Shigi 《Czechoslovak Journal of Physics》1996,46(Z3):1591-1592
The depinning temperatures in YBa2Cu3O7−δ ceramics and grains have been studied at magnetic field up to 4 T and various amplitudes of vibration. For ceramics sample,
large amplitude dependence of depinning temperature TD was observed, which indicate the decoupling of grains. In the case of a suspension sample (grain), TD was much lower than that of ceramics. 相似文献
594.
Kaoru Yamanouchi Takahiro Matsuzawa Kozo Kuchitsu Yoshiaki Hamada Masamichi Tsuboi 《Journal of Molecular Structure》1985
The quadratic force constants of the five possible conformers of allylamine were calculated by an ab initio MC method. The infrared spectra of this molecule in the gas phase were remeasured and analyzed on the basis of the calculated vibrational frequencies. A potential energy surface with respect to the skeletal torsions was also calculated. The relative abundances of the S+G+, ST, CT, CG, and S+G? conformers, predicted to be 44:32:16:7:1 at room temperature, are consistent with the experimental data. 相似文献
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596.
Kunihiro Hamada Toshiro Iijima Ralph McGregor 《Journal of Polymer Science.Polymer Physics》1988,26(2):421-432
The mobility of spin probes having a secondary, tertiary, or quaternary amino group in dried nylon films was investigated by means of electron spin resonance (ESR) measurements and compared with the behavior of previously investigated spin probes having a primary amino group, a carboxylate group, or a sulfate group. The spin probes having a primary or secondary amino group showed effects of drawing on the mobility, while the other probe molecules did not. This result could be interpreted by considering the interactions between the spin probes and the nylon chains. In the undrawn nylon film, the mobilities of the nonionic spin probes were almost the same, and smaller than those of the charged spin probes, suggesting that the location in the nylon film is different for the uncharged and charged spin probes. These results are discussed in detail using separation of extrema of the ESR spectra, rotational correlation times, and anisotropy parameters. 相似文献
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600.
Hidetaka Hamada 《Proceedings of the American Mathematical Society》1999,127(4):1075-1077
Let be an arbitrary norm on . Let be a normalized biholomorphic convex mapping on the unit ball in with respect to the norm . We will give an upper bound of the growth of .