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91.
Conventional guided-wave optical polarization splitters exhibit poor polarization extinction characteristics because of the necessity of controlling waveguide parameters. In order to improve the characteristics, an electrical control scheme was investigated in an alternating Δβ directional coupler. Polarization-dependent electrooptic as well as polarization-independent plasma effects were employed to produce high extinction for two orthogonal polarizations independently. As a result, an extinction ratio as high as 32 dB was obtained with a fabricated GaAs-GaAlAs device. This is the highest value ever reported with a channel waveguide device 相似文献
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Xue P Nomoto H Ueki N Takafuji M Ihara H 《Journal of nanoscience and nanotechnology》2008,8(1):314-320
To synthesize composite solid materials of metal salt and CdSe nanocrystals by a simple one-step method has been described. These solids can form stable gel in some organic solvent, such as benzene, cyclohexane and 1-butanol, especial in n-decane even below 0.1 wt/vol.%. Furthermore, these gels appear strong fluorescence which can be easily adjusted by the gel concentration. Temperature-dependent fluorescence spectra of composite gels suggested that the CdSe NCs aggregate together in gel state which would induce the energy transfer between nanocrystals and these aggregates could be reversibly disintegrated when gel was heated to form sol. TEM observations provided the further evidence of the energy transfer and suggested that the CdSe NCs were enchased regularly not only on the surface of self assembly of metal salt, but also embedded inside of self assembly in composite gel with small size nanocrystals. In contrast, in composite organogel with large nanocrystals they were only enchased on the edge of self assembly. 相似文献
96.
We present Emo System that extends e‐mail communication system in a workspace environment. In this system, the emotional information included in e‐mail message is extracted and shared in the public space, while reserving the private exchange of messages. As a result, people in the public space become aware of the ‘emotional’ information. This paper discusses how we extract and segment the information to share the emotional information. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
97.
Experimental investigations were carried out on the characteristics of the thermal field of a wall plume ascending from a horizontal line heat source embedded on the low part of a vertical wall surface. For the stability analysis of the present wall plume field, a vibrating copper wire was set horizontally near the line heat source in the field and the wall plume field was disturbed by the vibrating wire. Some two-dimensional sinusoidal thermal disturbances were introduced into the wall plume field and the growth or diminution of the amplitude of temperature fluctuations by the artificial disturbance were measured in the wall plume field with a thermal probe. The response characteristics of the wall plume field to the disturbance frequency were also examined. As a result, it was ascertained that the frequency response of a wall plume field could be predicted by linear stability analysis. © 1999 Scripta Technica, Heat Trans Asian Res, 28(7): 559–572, 1999 相似文献
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Ueki N. Sakamoto A. Nakamura T. Nakayama H. Sakurai J. Otoma H. Miyamoto Y. Yoshikawa M. Fuse M. 《Photonics Technology Letters, IEEE》1999,11(12):1539-1541
The authors have fabricated oxide-confined vertical-cavity surface-emitting lasers with metal apertures exhibiting a spatial mode filtering effect. Single-mode continuous-wave output is enhanced up to 3.4 mW by this effect for AlGaAs-based 780-nm vertical-cavity surface-emitting lasers with a 3.5-μm-diameter oxide aperture. From numerical calculations, the round-trip loss difference between zeroth- and first-order optical modes as a function of metal aperture size indicates that there is an optimum point; a 4-μm metal aperture size is suitable for higher order mode suppression of a 3.5-μm oxide aperture device 相似文献
100.
Thermal gels were made from white croaker (Pennahia argentata) surimi at various polymerization levels of myosin heavy chains induced by suwari treatment at 38 °C for various time periods and subsequently heated at 85 °C for 20 min. Myosin heavy chain polymerization levels were also achieved in the presence of microbial transglutaminase (MTG) added at various concentrations in the surimi. The breaking strength and breaking strain rate were markedly increased during suwari treatment up to 60 min in accordance with the increased levels of myosin heavy chain polymerization. MTG enhanced myosin heavy chain polymerization during suwari treatment for 15 and 30 min, resulting in the increase of breaking strength. The solubilization in 8 M urea and pepsin digestibility of these gels as well as angiotensin I‐converting enzyme (ACE) inhibitory activity of their pepsin digests were decreased with the increased levels of myosin heavy chain polymerization. These results suggest that myosin heavy chain polymerization affects not only rheological properties of thermal gels but also their functional properties for human health. 相似文献