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101.
We consider the Cauchy problem for the generalized Ostrovsky equation where f(u)=|u|ρ−1u if ρ is not an integer and f(u)=uρ if ρ is an integer. We obtain the L∞ time decay estimates and the large time asymptotics of small solutions under suitable conditions on the initial data and the order of the nonlinearity. 相似文献
utx=u+(f(u))xx,
102.
Differential scanning calorimetry (DSC) thermograms, X-ray diffraction (XRD) analysis, electrical conductivity (σ), and 7Li NMR spectroscopy characterization of n-C m H(2m?+?1)COOM solids (M = Li, Na, K; m?=?13, 15, 17, 19, 21) and mixed crystals n-C21H43COOLi x K(1???x) (0.25?≤?x?≤?0.75) was performed as a function of temperature. DSC thermograms of n-C m H(2m?+?1)COOM revealed several solid-solid phase transitions with large entropy changes. Electrical conductivity studies established that n-C m H(2m?+?1)COOLi crystals are poor electrical conductors. In contrast, n-C m H(2m?+?1)COOK salts were found to have σ values of 10???7–10???8 S·cm???1. Since the crystal structures and phase-transition temperatures of both n-C m H(2m?+?1)COOLi and n-C m H(2m?+?1)COOK crystals were similar, they were able to form mixed crystals with the structure n-C x H(2m?+?1)COOLi x K(1???x). DSC thermograms of the mixed crystals showed a small entropy change at the melting point (ΔS mp?<?13 J K???1 mol???1), in addition, large ΔS values at the solid-solid phase transition temperature. The σ values obtained for mixed crystals were roughly one order of magnitude greater than those determined for n-C21H43COOK crystals. 7Li NMR spectra of the mixed crystals recorded at various temperatures suggested that the self-diffusion of Li?+? ions was excited in the highest-temperature solid phase. Based on these results, we have classified these mixed crystals as rotator crystals. 相似文献
103.
ABSTRACT We present an algorithm to construct the automorphism group of a finite p-group. The method works down the lower exponent-p central series of the group. The central difficulty in each inductive step is a stabiliser computation; we introduce various approaches designed to simplify this computation. 相似文献
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108.
Hideto Tsuji Yoshiko Yamamura Tomoyuki Ono Takashi Saeki Hiroyuki Daimon Koichi Fujie 《大分子反应工程》2008,2(6):522-528
Aliphatic dicarboxylic acid/aliphatic diol‐derived polyesters, poly(butylene succinate) and poly(butylene succinate/adipate), have been hydrolytically degraded in the melt in high‐temperature and high‐pressure water over a wide temperature range of 180–300 °C for periods of up to 30 min. The formation/decomposition of succinic acid (SA), adipic acid (AA), and butane‐1,4‐diol (BD), plus the molecular weight change of PBS and PBSA were then investigated. SA and AA were recovered at maximum yields of 65–80%, whereas BD was recovered at a maximum yield of only 30%, probably because of its decomposition. The obtained results were compared with those reported for aliphatic hydroxycarboxylic acid‐derived polyesters and aromatic dicarboxylic acid/aliphatic diol‐derived polyesters.
109.
Wang GX Han GF Ye Q Xiong RG Akutagawa T Nakamura T Chan PW Huang SD 《Dalton transactions (Cambridge, England : 2003)》2008,(19):2527-2530
A homochiral rare-earth metal Tb complex that exhibited a very large dielectric anisotropic property with a temperature-independent feature is obtained. Our findings on high-dielectric anisotropy will provide a new impetus in this field of materials science. 相似文献
110.
Taichi Kusakabe Satoshi Takaishi Tomoyuki Mochida Tat'yana A. Peganova Oleg V. Gusev 《Tetrahedron》2008,64(2):319-327
Oxidative cyclization-carbonylation of 2-alkyl-2-propargylcyclohexane-1,3-diones mediated by Pd(TFA)2/2,2′-isopropylidenebis[(4R)-4-(3,4-dimethoxyphenyl)-2-oxazoline] 28 afforded bicyclic-β-alkoxyacrylates in 51-74% yields with 72-82% ee. The products containing quaternary carbon were converted to optically active hydrindanes 33. 相似文献