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101.
Kittaka S Takahara S Yamaguchi T Funel MC 《Langmuir : the ACS journal of surfaces and colloids》2005,21(4):1389-1397
The dynamics of water molecules in the layered vanadium pentoxide hydrate, V(2)O(5).nH(2)O, were studied by quasi-elastic neutron scattering (QENS) measurements. Heterogeneity of the dynamic properties was confirmed by alpha-relaxation model analysis. Translational diffusion of monolayer and double-layer water molecules is by site-to-site diffusion and is reduced relative to that of bulk water. Water molecules lose their mobility markedly and solidify with decreasing temperature. However, mobile water remains at 253 K. Rotational diffusion coefficients are unaffected by confinement and are very similar to the bulk values determined at temperatures in the range 253-298 K. The dynamic speed characterized by QENS is much faster than that expected from the data determined by deuterium NMR (DNMR) measurements at low temperatures. 相似文献
102.
The total synthesis of (±)-dithiathromboxane A2 sodium salt 1 was accomplished in 26 steps from methyl 4,4-dimethoxyactoacetate. 相似文献
103.
(+)-11a-methano-9,11-thiathiromboxane A2(1) was synthesized from prostaglandin A2 and prostaglandin E2. 相似文献
104.
105.
Human blood group substance of the ABO system was immobilized in a mebrane matrix. The membrane-bound blood group substance retained its binding ability against the corresponding antibody (agglutinin) in serum. The transmembrane potential changed drastically with the agglutination of the membrane-bound blood group substance. Electrochemical typing of blood was performed with sera, using a pair of membranes with immobilized A- and B-type blood group substances. The blood type was determined by measuring the transmembrane potential across these membranes before and after the agglutination reaction. A possible re-use of the membrane-bound blood group substance by treatment with galactose is discussed. 相似文献
106.
Takashi Kushida Shuichi Kinoshita Hironobu Ohta Takashi Morie 《Solid State Communications》1980,35(3):267-271
Time characteristics of secondary emissions have been measured in ZnTe at 82K under the excitation into the fundamental absorption band by subnanosecond light pulses. The decay time of polariton luminescence has been determined to be about 100 ps. On the other hand, the time behavior of the intensity of the sharp 2LO-phonon line has been found to coincide with that of the exciting pulse. This result is consistent with the resonance Raman scattering mechanism. 相似文献
107.
The CNDO/2 and INDO calculations were performed on s-triazine and s-tetrazine. The s-triazine has three lone-pairs in a molecule, and these can be combined into three combinations, A, ns and nA. Among the three, ns and nA are degenerated when the whole interaction conserves its molecular point symmetry, D3h. The s-tetrazine has four lone-pairs, which can be transformed into four combinations, SS,SA, AS and AA. The energies of these orbitals show interesting behavior. The results were subjected to an analysis from the standpoint of the through-space and through-bond interactions using the localized molecular orbitals. As a result of these analyses, the interactions were expressed by several interaction terms. 相似文献
108.
Chen Y Pai A Somiya K Kawamura S Sato S Kokeyama K Ward RL Goda K Mikhailov EE 《Physical review letters》2006,97(15):151103
We propose a class of displacement- and laser-noise-free gravitational-wave-interferometer configurations, which does not sense nongeodesic mirror motion and laser noise, but provides a nonvanishing gravitational-wave signal. Our interferometers consist of four mirrors and two beam splitters, which form four Mach-Zehnder interferometers. By contrast to previous works, no composite mirrors with multiple reflective surfaces are required. Each mirror in our configuration is sensed redundantly, by at least two pairs of incident and reflected beams. Displacement- and laser-noise-free detection is achieved when output signals from these four interferometers are combined appropriately. Our 3-dimensional interferometer configuration has a low-frequency response proportional to f2, which is better than the f3 achievable by previous 2-dimensional configurations. 相似文献
109.
Numata M Tamesue S Fujisawa T Haraguchi S Hasegawa T Bae AH Li C Sakurai K Shinkai S 《Organic letters》2006,8(24):5533-5536
We have demonstrated that one-dimensional supramolecular dye assemblies with a uniform diameter can be created by utilizing schizophyllan (SPG) as a one-dimensional host. In the supramolecular nanofibers, the dye molecules are assembled into the different aggregation modes depending on the preparation procedures. The findings establish that SPG is useful for creating the supramolecular nanofibers, where temporal superstructures can be stabilized by the SPG-specific helical higher-order structure. [structure: see text]. 相似文献
110.
A new method to determine a coupling function in a phase model is theoretically derived for coupled self-sustained oscillators and applied to Belousov-Zhabotinsky (BZ) oscillators. The synchronous behavior of two coupled BZ reactors is explained extremely well in terms of the coupling function thus obtained. This method is expected to be applicable to weakly coupled multioscillator systems, in which mutual coupling among nearly identical oscillators occurs in a similar manner. The importance of higher-order harmonic terms involved in the coupling function is also discussed. 相似文献