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641.
We study the initial value problem for some semilinear damped beam equation. In Takeda and Yoshikawa (submitted for publication) [9] unique global existence of a decaying solution for the problem and the smoothing effect of the solution was shown. In this article we shall give the asymptotic profiles of the solution. As a result, we observe that the decay estimates are optimal. Moreover, considering the higher order expansion of the solution, we observe more detailed information such as the contribution of the nonlinear term to the solution as . 相似文献
642.
Dalgleish S Matsushita MM Hu L Li B Yoshikawa H Awaga K 《Journal of the American Chemical Society》2012,134(30):12742-12750
Photodetection based on bis-(4-dimethylaminodithiobenzil)-Ni(II) (BDN), a representative and well-studied metal dithiolene that shows strong absorption in the near-infrared region of the electromagnetic spectrum, has been investigated. By adopting a metal/insulator/semiconductor/metal (MISM) structure, the peak photocurrent response to an oscillating light chain is increased by up to 50 times, compared to devices without an insulating layer. The transient form of the MISM photoresponse, while unsuitable for steady-state photodetection, can be used to detect periodic light signals of frequencies up to 1 MHz, and is thus applicable for optical communication. Further improvements have been realized by nanostructuring carbon black into the dithiolene layer, improving charge collection, and yielding detectivity of up to 1.6 × 10(11) Jones at wavelengths beyond the scope of silicon photodiodes. Such an architecture may allow the favorable absorption properties of other such metal dithiolenes to be harnessed, where their low charge carrier mobilities and short excitation lifetimes have previously limited their applicability to this field. 相似文献
643.
Masayoshi Yoshikawa 《Discrete Mathematics》2018,341(7):2028-2034
In the present paper, we will define the higher Frobenius–Schur indicators and the higher indicators of association schemes as a generalization of those of finite groups. The higher indicators of any association scheme are always positive rational numbers. Especially, for any positive integer , the th indicator of any regular association scheme is the number of relations such that its strong girth divides . Thus, all higher indicators of any regular association scheme are natural numbers, and the sequence of the indicators is periodic. We will show that the converses of these facts are also true for finite exponent association schemes. Finally, we introduce a family of infinite exponent association schemes all higher indicators of which are natural numbers and the sequence of the indicators of which is periodic. 相似文献
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645.
J. B. Shim A. Yoshikawa M. Nikl J. Pejchal A. Vedda T. Fukuda 《Radiation measurements》2004,38(4-6):493-496
Yb3+-doped YAlO3 single crystals were grown by the Czochralski method with a radio frequency heating system. The starting melt compositions of Y1−xYbxAlO3 were varied as x=0.02, 0.1, 0.2, 0.3 and 0.45. Photo- and thermo-luminescence characteristics including emission decays were measured within 4–300 K. Very fast charge transfer luminescence of Yb3+ was found, with the typical double peak spectrum at 345 and 525 nm. At room temperature the photoluminescence and scintillation decay curves show a leading subnanosecond decay component without any additional slower processes. The high density of Yb-rich YAlO3 makes this material a promising candidate for fast scintillators. 相似文献
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647.
We have investigated the pressure dependence of the Raman active intramolecular modes in anthracene-TCNQ, pyrene-TCNQ, and alkali-TCNQ salts in the pressure range between 0 kbar abd 30 kbar. The measured value of the fractional frequency variation with pressure, dlnν4/dP, for the ν4 mode (C=C wing stretching) of TCNQ- molecules is approximately twice as large as that of TCNQ°. This observation is interpreted as due to a change in the electronic charge distribution on the C=C wing bond region of the TCNQ- molecules at high pressures. 相似文献
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