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101.
Tsuneo Imamoto Masatoshi Matsuo Taro Nonomura Kuniyuki Kishikawa Masao Yanagawa 《Heteroatom Chemistry》1993,4(5):475-486
Cyclohexyl(o-methoxyphenyl)menthyloxyphosphineborane and t-butyl(o-methoxyphenyl)menthyloxyphosphine-borane were prepared from dichlorocyclohexylphosphine and t-butyldichlorophosphine by successive treatments with (−)-menthol, o-methoxyphenylmagnesium bromide, and borane-THF complex. The separated pure diastereomers of each of the compounds underwent reaction with lithium naphthalenide to afford optically pure cyclohexyl(o-methoxyphenyl)phosphine-borane and t-butyl(o-methoxyphenyl)phosphine-borane, respectively. These secondary phosphine-boranes reacted readily with various electrophiles in the presence of bases with virtually net retention of configuration. A new chiral phosphine ligand, (S,S)-1,2-bis[cyclohexyl(o-methoxyphenyl)phosphino]ethane was synthesized via the optically pure phosphine-boranes. 相似文献
102.
Meccanica - The static deformation of symmetric bow limbs has been widely studied in the last century. However, asymmetries in shape and length which correspond to a more realistic situation, have... 相似文献
103.
H. Hanabata T. Matsuo H. Suga 《Journal of inclusion phenomena and macrocyclic chemistry》1987,5(3):325-333
Heat capacities of crystalline-cyclodextrin undecahydrate have been measured in the temperature range between 13 and 300K by use of a miniaturized adiabatic low-temperature calorimeter. A first-order phase transition occurred at 226K with a discontinuous entropy change of 45.0 ± 1.0J
K
–1 mol–1. The highly disordered nature of the high temperature phase was considered in relation to the entropy contribution. A glass transition phenomenon observed around 150K was ascribed to the freezing of a configurational change of the protons engaged in the four-membered hydrogen-bonded ring which appeared only in the low temperature phase. 相似文献
104.
N. Matsuo 《Zeitschrift fur Physik C Particles and Fields》1987,36(2):289-304
The thermodynamics of superstring theories (SST-I, SST-II and heterotic string theory) and its application to the cosmology are studied. The free energy of superstring gas is calculated in the one-loop approximation and the stability of the extra torus dimensions is discussed. Assuming that the Einstein equation dictates the evolution of the universe, we show that matter dominated universe filled with massive particles would never be realized at the beginning of the universe, contrary to the naive expectation in the superstring cosmology. 相似文献
105.
Reizo Kato Hayao Kobayashi Takehiko Mori Akiko Kobayashi Yukiyoshi Sasaki 《Solid State Communications》1985,55(5):387-392
In the crystals of the cation radical salts based on the organic donor BMDT-TTF, the charge separation is observed. This comes from (1) nonequivalency of the site potential and (2) the long range electron-electron interaction, which are related to the two-dimensional nature of the molecular arrangement. The effects of the charge separation on the elctronic structure are discussed. 相似文献
106.
Takaharu Yaguchi Takayasu Matsuo Masaaki Sugihara 《Journal of Computational and Applied Mathematics》2010,234(4):1036-1048
The Ostrovsky equation describes gravity waves under the influence of Coriolis force. It is known that solutions of this equation conserve the L2 norm and an energy function that is determined non-locally. In this paper we propose four conservative numerical schemes for this equation: a finite difference scheme and a pseudospectral scheme that conserve the norm, and the same types of schemes that conserve the energy. A numerical comparison of these schemes is also provided, which indicates that the energy conservative schemes perform better than the norm conservative schemes. 相似文献
107.
Kensuke Aishima Takayasu Matsuo Kazuo Murota Masaaki Sugihara 《Journal of Computational and Applied Mathematics》2010,234(4):1179-1187
DLASQ is a routine in LAPACK for computing the singular values of a real upper bidiagonal matrix with high accuracy. The basic algorithm, the so-called dqds algorithm, was first presented by Fernando-Parlett, and implemented as the DLASQ routine by Parlett-Marques. DLASQ is now recognized as one of the most efficient routines for computing singular values. In this paper, we prove the asymptotic superquadratic convergence of DLASQ in exact arithmetic. 相似文献
108.
The heat capacity of thallium dihydrogen phosphate was measured from 12 to 300 K. A lambda anomaly with a small first order discontinuity was found at 229.76 K with the integrated enthalpy and entropy changes equal to 370 J mol-1 and 1.8 J K-1 mol-1, respectively. The entropy discontinuity at the first order transition is 0.25 J K-1 mol-1. The Landau theory of phase transitions of the second kind reproduces closely the temperature dependence of the anomalous heat capacity. This, together with the small discontinuity in the entropy, implies that the phase transition is close to a classical critical point of higher order. The relative dielectric permittivity ?r(b) along the b-axis at 1 kHz is anomalously large and strongly temperature dependent, while the ?r(a1) and ?r(c) are not. A broad absorption centered at 1700 cm-1 was observed in the infrared absorption spectrum, indicating presence of hydrogen bonding of the length ~ 0.25 nm. Occurrence of a phase transition at 127 ± 2 K was suggested by differential thermal analysis of thallium dideuterium phosphate. 相似文献
109.
Hisahiro Nakayama Jiro Kasahara Akiko Matsuo Ikkoh Funaki 《Proceedings of the Combustion Institute》2013,34(2):1939-1947
The propagation of curved detonation waves of gaseous explosives stabilized in rectangular-cross-section curved channels is investigated. Three types of stoichiometric test gases, C2H4 + 3O2, 2H2 + O2, and 2C2H2 + 5O2 + 7Ar, are evaluated. The ratio of the inner radius of the curved channel (ri) to the normal detonation cell width (λ) is an important factor in stabilizing curved detonation waves. The lower boundary of stabilization is around ri/λ = 23, regardless of the test gas. The stabilized curved detonation waves eventually attain a specific curved shape as they propagate through the curved channels. The specific curved shapes of stabilized curved detonation waves are approximately formulated, and the normal detonation velocity (Dn)?curvature (κ) relations are evaluated. The Dn nondimensionalized by the Chapman–Jouguet (CJ) detonation velocity (DCJ) is a function of the κ nondimensionalized by λ. The Dn/DCJ?λκ relation does not depend on the type of test gas. The propagation behavior of the stabilized curved detonation waves is controlled by the Dn/DCJ?λκ relation. Due to this propagation characteristic, the fully-developed, stabilized curved detonation waves propagate through the curved channels while maintaining a specific curved shape with a constant angular velocity. Self-similarity is seen in the front shock shapes of the stabilized curved detonation waves with the same ri/λ, regardless of the curved channel and test gas. 相似文献
110.
Yoshinori Matsuo Sang-Jin Sin Shingo Takeuchi Takuya Tsukioka Chul-Moon Yoo 《Nuclear Physics B》2009,820(3):593-619
In the previous paper we studied the transport coefficients of quark–gluon plasma in finite temperature and finite density in vector and tensor modes. In this paper, we extend it to the scalar modes. We work out the decoupling problem and hydrodynamic analysis for the sound mode in charged AdS black hole and calculate the sound velocity, the charge susceptibility and the electrical conductivity. We find that Einstein relation among the conductivity, the diffusion constant and the susceptibility holds exactly. 相似文献