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91.
92.
We have demonstrated three beam non-degenerate reflected four-wave mixing (reflected FWM) in which two driving fields have the same photon energy (?ω1) and the monitor and the resulting mixed light fields have another equal photon energy (?ω2). Mixed light has been observed with the driving field's energy from Z3 exciton up to band gap energy when ?ω2 is fixed in the Z3 and Z1,2 exciton resonance region. The mechanism by which such non-degenerate optical non-linearity occurs is discussed according to a calculation by a simple model. 相似文献
93.
94.
Masuda A Ushida K Nishimura G Kinjo M Tamura M Koshino H Yamashita K Kluge T 《The Journal of chemical physics》2004,121(21):10787-10793
The distance dependence of the diffusion coefficient (DDDC) of a globular protein (cytochrome c) in aqueous hyaluronan (HA) solution, which is a model system for extracellular matrices (ECMs), was measured by a combination of three kinds of spectroscopic measurements of diffusion coefficients, the time and space samplings of which are different. The results of the three methods are plotted against the diffusion distance derived from the consideration of each experimental condition. Due to the characteristic morphology of HA with an effective mesh structure, the proteins showed two extreme diffusion modes: (1) short (<10 nm) diffusion with rare contact with polymer chains; (2) long (>100 nm) diffusion significantly disrupted by polymer chains showing an approximately 30% reduction in diffusion coefficient. The transition from the short diffusion to the long one occurs in a very narrow range (10-100 nm) of diffusion distance and this unique character of HA realizing anomalous diffusion should provide suitable environments for various bioactivities when involved in ECM. 相似文献
95.
96.
The existence, uniqueness and regularity of strong solutions for Cauchy problem and periodic problem are studied for the evolution equation:
where is the so-called subdifferential operator from a real Banach space V into its dual V*. The study in the Hilbert space setting (V = V* = H: Hilbert space) is already developed in detail so far. However, the study here is done in the V–V* setting which is not yet fully pursued. Our method of proof relies on approximation arguments in a Hilbert space H. To assure this procedure, it is assumed that the embeddings
are both dense and continuous. 相似文献
97.
98.
Mitsutomo Hirota Takeshi Yokomori Yoshitaka Nagai Goro Masuya 《Proceedings of the Combustion Institute》2007,31(1):893-899
We investigated the local flame speed of a two-dimensional, methane-air triple flame in a rectangular burner. The velocity fields and the concentration profiles were measured with particle image velocimetry and the Rayleigh scattering method, respectively. There was a requisite combination of initial velocity and initial concentration gradient for consistency of the local concentration gradient at the leading edge of the flame. In these cases, the flame curvatures were also consistent. Accordingly, the burning velocity, defined as local flow velocity at the triple point, was determined by the flame curvature. The burning velocity increased with increasing flame curvature, when the curvature was near zero. After that, the burning velocity decreased with increasing curvature. The peak value thus exceeded the adiabatic one-dimensional laminar burning velocity. Comparing the effects of the measured flame stretch rate on the flow strain κs and flame curvature κc, κs is larger and increases more rapidly than κc for flame curvatures satisfying 1/Rf < 250 m−1 and then becomes constant while κc still increases for 250 m−1 < 1/Rf, so that κc becomes much larger than κs. There is also a peak in burning velocity at roughly the transition in flame curvature specified above. Therefore, the burning velocity for a low concentration gradient correlates with the flame stretch rate. 相似文献
99.
Modifications of epitaxy in Ge, Si, CdS, β-Sn, and α-Fe films, 100–600 Å in thickness, evaporated onto air-cleaved and vacuum-cleaved (001) NaCl substrates under electron bombardment (∽1015 electrons/cm2 sec, at 200–400 V) or an electric field (dc 100–300 V/cm) applied to the substrate surface were investigated by reflection electron diffraction, transmission electron microscopy and selected-area diffraction. Results indicated that epitaxial temperatures of Ge and Si films were considerably lowered, and a monocrystalline β-Sn film was produced by the application of electron bombardment. The application of electric field resulted in the formation of an epitaxial cubic CdS phase, and a single orientation in an α-Fe film. These results are discussed in terms of current speculation concerning the electric charge effects on alkali halide substrates. 相似文献
100.
Y Kawashima M Sato Y Hatada J Goto Y Yamane K Hatayama 《Chemical & pharmaceutical bulletin》1991,39(12):3202-3206
A series of 3-acylidene-4-methylazetidin-2-one derivatives bearing various substituents at the 1-position of the azetidin-2-one ring was synthesized. These compounds were evaluated for platelet aggregation inhibitory activities. Most of the compounds synthesized showed potent inhibitory activities against rabbit platelet aggregation induced by adenosine diphosphate or collagen in vitro. Structure-activity relationships are also discussed. 相似文献