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21.
Yasuo Kokubun 《光学学报》2003,23(Z1)
In this review, the recent progress in the development of vertically coupled micro-ring resonator filters is summarized and the potential applications of the filters leading to the development of VLSI photonics are described. 相似文献
22.
A wide range (9.4nm) tuning of vertically coupled microring resonator filter was demonstrated utilizing a large TO coefficient of polymer. The power consumption was about 60mW and no degradation of filter response was observed. 相似文献
23.
Makoto Sakata Takafumi Itsubo Yutakata Moritomo Yasuo Ohishi 《Journal of Physics and Chemistry of Solids》2004,65(12):1973-1976
The experimental and analytical method of the high-pressure powder experiment at BL10XU, SPring-8, is described. There is no doubt that BL10XU must be one of the most appropriate beam lines for high pressure X-ray diffraction experiment taking advantage of third generation synchrotron source. As an example of the advanced charge density study under high pressure, the structural change of Cs2Au2Br6 by applying pressure is studied by Rietveld/MEM analysis. It reveals that the structural change of Cs2Au2Br6 by applying pressure occurs basically at electron level, such as valence state change and chemical bonding, which may be called the electronic phase transition. 相似文献
24.
A four-dimensional Walker geometry is a four-dimensional manifold M with a neutral metric g and a parallel distribution of totally null two-planes. This distribution has a natural characterization as a projective
spinor field subject to a certain constraint. Spinors therefore provide a natural tool for studying Walker geometry, which
we exploit to draw together several themes in recent explicit studies of Walker geometry and in other work of Dunajski [11]
and Pleba?ski [30] in which Walker geometry is implicit. In addition to studying local Walker geometry, we address a global
question raised by the use of spinors. 相似文献
25.
The anomalous temperature dependence of the sign of the spontaneous polarization in a biphenyl ester series of ferroelectric liquid crystals is reported. The reversal of the sign of the spontaneous polarization in the chiral smectic C phase of 2MBNCBC ((S)-2′-methylbutyl-4′-n- nonylcarbonyloxy-(l,l′-biphenyl)-l-carboxylate) is observed at T m. This anomaly is studied in detail as functions of the length of the terminal alkyl chain, the applied electric field, the frequency and the applied hydrostatic pressure. T m has been confirmed to depend on the length of the terminal chain and the applied pressure. However, it is independent of the applied field and the measuring frequency. In the mixture of these compounds, this anomaly is also observed. 相似文献
26.
Yasuo Horikawa Takeshi Takeda Toshiki Takizawa Taro Akazawa Ryota Fujio Tatsuo Fujimaki 《Journal of polymer science. Part A, Polymer chemistry》1996,34(7):1183-1188
The anionic polymerization of 1,3-butadiene using a novel metalloidal anion initiator, triallylstannyllithium (TALi)-allyllithium (ALi), was studied. The TALi-ALi initiated anionic polymerization of 1,3-butadiene gave the star polymer along with the linear polybutadiene (PBD). The star polymer consisted of three PBD branches and a central tin atom. What is striking is a fact that the number-average molecular weights (Mn) and molecular weight distribution of three PBD branches and linear PBD were almost identical. A reversible chain transfer polymerization mechanism, which includes the equilibrium between tri(macroallyl)-stannyllithium and macroallylic anion, is proposed. © 1996 John Wiley & Sons, Inc. 相似文献
27.
Masaru Yoshida Masaharu Asano Hideki Omichi Masaharu Miyajima Yasuo Takahashi Hidetoshi Yamanaka Noriyuki Yonezawa Ryoichi Katakai 《Macromolecular theory and simulations》1993,2(3):377-384
The loosely cross-linked poly(acryloyl-L -proline methyl ester) gel, which is known as one of the typical thermo-responsive gels, shows a volume transition around approximately 14°C in pure water. This volume transition is shifted to higher temperature by treatment in aqueous sodium dodecyl sulfate (SDS). The analysis of the swelling-temperature curve (frequency distribution) was performed according to a moment analysis, in which the area under the swelling-temperature curve (AUC), mean swelling transition temperature (MSTT) and variance of swelling transition temperature (VSTT) were calculated. It is shown that the apparent volume transition temperature can be estimated from MSTT and that VSTT can be used to characterize the shape of the corresponding curves. 相似文献
28.
Tomohiro Takano Chutiparn Lertvachirapaiboon Yasuo Ohdaira Akira Baba Keizo Kato 《Molecular Crystals and Liquid Crystals》2019,685(1):93-99
AbstractGas sensing by using the transmission surface plasmon resonance (T-SPR) technique was demonstrated. Polyacrylic acid (PAA)/5-nm-thick gold/40-nm-thick silver/polycarbonate grating substrate structure (Sensor A) responded to ammonia; however, it exhibited a strong humidity dependence. Polyvinyl alcohol (PVA)/5-nm-thick gold/40-nm-thick silver/polycarbonate grating substrate structure (Sensor B) as the sensing material was also prepared and it mainly responded to humidity. The T-SPR properties of Sensors A and B were observed simultaneously by a stacking arrangement that enabled us to obtain the responses by using a single spectrophotometer. The ammonia concentration under various humidity conditions could be accurately obtained by simultaneous measurement of Sensors A and B. 相似文献
29.
30.
- , [4]. , . 相似文献