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1.
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3.
An InGaAs/InAlAs five-layer asymmetric coupled quantum well (FACQW) is expected to show very large electrorefractive index change. n in a wideband transparency region. Band structures of the FACQW are analyzed with Luttinger-Kohn Hamiltonian. The electrorefractive characteristics of the FACQW are discussed. 相似文献
4.
The interaction of two parallel plane jets of different velocities is studied by flow visualization and PIV measurement to
examine the influence of velocity ratio on the development ofjets in the initial region. It is found that the parallel plane
jets develop toward the high velocity side and the jet width is reduced with a decrease in the jet velocity ratio. Corresponding
to the variation of mean velocity field to the velocity ratio, the magnitudes of turbulence intensities, Reynolds stress and
static pressure are weakened in the merging region of the jets and their peak locations of the properties are shifted to the
high velocity side. These results indicate that the interaction of two parallel jets is weakened with a decrease in the velocity
ratio of the jets. 相似文献
5.
6.
Kentaro Suzuki Taro Toyota Katsuhiko Sato Masakazu Iwasaka Shoogo Ueno Tadashi Sugawara 《Chemical physics letters》2007,440(4-6):286-290
Collagen-containing tubular giant vesicles (Col–tGVs) under a high static magnetic field were found to constitute characteristic curved structures (e.g. circular, 8-figure, and hairpin-loop), which were sustained by polymerization of collagen units inside the tGV. We ascribed the formation of these structures to the elasticity of the tGV and to the competing diamagnetic anisotropies between collagen and the tGV. These curved structures can be well expressed by the equation of elastica. 相似文献
7.
Summary {\rtf1\ansi\ansicpg1250\deff0\deflang1038\deflangfe1038\deftab708{\fonttbl{\f0\froman\fprq2\fcharset238{\*\fname Times New Roman;}Times New Roman CE;}}
\viewkind4\uc1\pard\f0\fs20 New explanations are given for two types of irregular thermogravimetric (TG) data. A TG relationship between mass and temperature is derived on the basis of migration behavior of bubbles generated in bulk of sample system, and superposed on that derived on the basis of kinetics of the 4\super th\nosupersub order event, which is superposed on the experimental TG data obtained from three reference papers. This suggests that these TG data are reflecting migration of bubbles. A dependence of TG behavior on heating rate, which is contrary to usual that, is shown and is explained in terms of event-rate determination by boiling.
\par } 相似文献
8.
Summary Pyridinium ylide complexes of methylcobaloxime were synthesized by the treatment of an ylide with Co(Hdmg)2 Me(SMe2). The crystal structure of one of the complexes, [Co(Hdmg)2Me C5H5NCHCOPh]C6H6 has been determined by x-ray diffraction techniques. The crystals are monoclinic, space group P21/c, witha = 10.456(5),b = 11.079(4),c = 24.58(1) Å, = 99.58(6), V = 2808 Å3, Z = 4. The Co-C (ylide) bond distance is 2.18 Å and Co-C(methyl) 2.04 Å. C(ylide)-Co-C(methyl) bond angle is 174.9°. The crystal, i.r. and1H n.m.r. data suggest that thetrans-influence of the ylide ligands is larger than that of py, Melm, OH2 or PPh3. 相似文献
9.
M. Fujisawa T. Matsushita Y. Matsui K. Akasaka T. Kimura 《Journal of Thermal Analysis and Calorimetry》2004,77(1):225-231
The heat capacities of binary aqueous solutions of 1,2-ethanediol, 1,2-propanediol and 1,2-butanediol were measured at temperatures
ranging from 283.15 to 338.15 K by differential scanning calorimetry. The partial molar heat capacities at the infinite dilution
were then calculated for the respective alkanediols. For 1,2-ethanediol or 1,2-propanediol, the partial molar heat capacities
at the infinite dilution of increased with increasing temperature. In contrast, the partial molar heat capacities of 1,2-butanediol
at the infinite dilution decreased with increasing temperature.
Heat capacity changes by dissolution of the alkanediols were also determined. Heat capacity changes caused by the dissolution
of 1,2-ethanediol or 1,2-propanediol were increase with increasing temperature. On the other hand, heat capacity changes caused
by the dissolution of 1,2-butanediol are decrease with increasing temperature. Thus our results indicated that the structural
changes of water caused by the dissolution of 1,2-butanediol differed from that of the two other alkanediols.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
T. Kimura Y. Takahashi T. Kamiyama M. Fujisawa 《Journal of Thermal Analysis and Calorimetry》2007,88(2):587-595
Excess enthalpies (H
E)
of 17 binary mixtures of o- and m-isomers of dichlorobenzene, difluorobenzene, methoxymethylbenzene,
dimethylbenzene, dimethoxybenzene, aminofluorobenzene, fluoronitrobenzene,
diethylbenzene, chlorofluorobenzene, fluoroiodobenzene, bromofluorobenzene,
chloromethylbenzene, fluoromethylbenzene, bromomethylbenzene, iodomethylbenzene,
fluoromethoxybenzene, dibromobenzene at 298.15 K were measured. All excess
enthalpies measured were very small, and those of o-+m-isomers of aminofluorobenzene, dibromobenzene and
iodomethylbenzene were negative but 14 other binary mixtures of isomers were
positive over the whole range of mole fractions. H
E
of o-+m-isomers
of dimethoxybenzene showed the largest enthalpic instability and those of
aminofluorobenzene showed the largest enthalpic stability. There was a correlation
between dipole–dipole interaction, dipole–induced dipole interaction
or entropies of vaporization and excess partial molar enthalpies at infinite
dilution. 相似文献