The wind turbine with a flanged-diffuser shroud—so called “wind-lens turbine”—is developed as one of high performance wind turbines by Ohya et al. In this paper, the wind turbine performance is investigated for bo...The wind turbine with a flanged-diffuser shroud—so called “wind-lens turbine”—is developed as one of high performance wind turbines by Ohya et al. In this paper, the wind turbine performance is investigated for both steady and unsteady winds. The compact-type wind lens turbine shows higher efficiency than the only rotor wind turbine. Also, the flow structure around the compact-type wind turbine is made clear by CFD and PIV in steady wind. Furthermore, the performances of the only rotor and the compact-type wind-lens turbines for unsteady wind are experimentally and numerically investigated. Experimental and numerical results are presented to demonstrate the dependence of frequency of the harmonic oscillating velocity wind on power coefficient. Consequently, the compact-type wind-lens turbine show better performance than the only rotor one in sinusoidally oscillating velocity wind. Furthermore, the numerical estimation can predict the power coefficient in the oscillating flows to an accuracy of 94% to 102%. In addition, the dependence of the turbine performance on turbulent intensity and vortex scale of natural fluctuating wind is presented.展开更多
A water-soluble cyclophane (1) having poly(ethylene glycol) (PEG) moieties has been prepared from a tetraazide-functionalized cyclophane derivative and four poly(ethylene glycol) methyl ether acetylenes by Cu(I)-catal...A water-soluble cyclophane (1) having poly(ethylene glycol) (PEG) moieties has been prepared from a tetraazide-functionalized cyclophane derivative and four poly(ethylene glycol) methyl ether acetylenes by Cu(I)-catalyzed 1,3 dipolar cycloadditions (click chemistry). An analogous derivative having a pyrene moiety (2) was also prepared in a similar manner. The guest-binding behavior of 1 and 2 toward anionic guests such as 6-p-toluidinonaphthalene-2-sulfonate was investigated by fluorescence spectroscopy. The binding constants (K) of the host-guest complexes were evaluated.展开更多
Er_(x)Y_(2−x)SiO_(5) and Er_(x)Yb_(y)Y_(2−x−y)SiO_(5) crystalline thin films were investigated to apply to the high-gain media for silicon photonics.In addition to the sol–gel method,the directed self-assembly approa...Er_(x)Y_(2−x)SiO_(5) and Er_(x)Yb_(y)Y_(2−x−y)SiO_(5) crystalline thin films were investigated to apply to the high-gain media for silicon photonics.In addition to the sol–gel method,the directed self-assembly approach,using layer-by-layer deposition techniques,was also introduced to improve the crystallinity.The relaxation processes in Er ions were discussed to clarify the contribution of the energy transfer and cooperative upconversion.After optimization of the Er content,a Si photonic crystal slot Er_(x)Y_(2−x)SiO_(5) waveguide amplifier was fabricated,and a 30 dB∕cm modal gain was demonstrated.This achievement demonstrates the potential for compact and high optical gain devices on Si chips.展开更多
文摘The wind turbine with a flanged-diffuser shroud—so called “wind-lens turbine”—is developed as one of high performance wind turbines by Ohya et al. In this paper, the wind turbine performance is investigated for both steady and unsteady winds. The compact-type wind lens turbine shows higher efficiency than the only rotor wind turbine. Also, the flow structure around the compact-type wind turbine is made clear by CFD and PIV in steady wind. Furthermore, the performances of the only rotor and the compact-type wind-lens turbines for unsteady wind are experimentally and numerically investigated. Experimental and numerical results are presented to demonstrate the dependence of frequency of the harmonic oscillating velocity wind on power coefficient. Consequently, the compact-type wind-lens turbine show better performance than the only rotor one in sinusoidally oscillating velocity wind. Furthermore, the numerical estimation can predict the power coefficient in the oscillating flows to an accuracy of 94% to 102%. In addition, the dependence of the turbine performance on turbulent intensity and vortex scale of natural fluctuating wind is presented.
文摘A water-soluble cyclophane (1) having poly(ethylene glycol) (PEG) moieties has been prepared from a tetraazide-functionalized cyclophane derivative and four poly(ethylene glycol) methyl ether acetylenes by Cu(I)-catalyzed 1,3 dipolar cycloadditions (click chemistry). An analogous derivative having a pyrene moiety (2) was also prepared in a similar manner. The guest-binding behavior of 1 and 2 toward anionic guests such as 6-p-toluidinonaphthalene-2-sulfonate was investigated by fluorescence spectroscopy. The binding constants (K) of the host-guest complexes were evaluated.
基金This work was supported in part by JSPS KAKENHI Grant Number 22560003 and the Core-to-Core Program.
文摘Er_(x)Y_(2−x)SiO_(5) and Er_(x)Yb_(y)Y_(2−x−y)SiO_(5) crystalline thin films were investigated to apply to the high-gain media for silicon photonics.In addition to the sol–gel method,the directed self-assembly approach,using layer-by-layer deposition techniques,was also introduced to improve the crystallinity.The relaxation processes in Er ions were discussed to clarify the contribution of the energy transfer and cooperative upconversion.After optimization of the Er content,a Si photonic crystal slot Er_(x)Y_(2−x)SiO_(5) waveguide amplifier was fabricated,and a 30 dB∕cm modal gain was demonstrated.This achievement demonstrates the potential for compact and high optical gain devices on Si chips.
