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121.
根据光的偏振特性,利用偏振片制作机动车前大灯和偏振片眼镜,实践证明,可以提高机动车夜间行车的安全性. 相似文献
122.
A Cartesian grid method using immersed boundary technique to simulate the impact of body in fluid has become an important research topic in computational fluid dynamics because of its simplification, automation of grid generation, and accuracy of results. In the frame of Cartesian grid, one often uses finite volume method with second order accuracy or finite difference method. In this paper, an h‐adaptive Runge–Kutta discontinuous Galerkin (RKDG) method on Cartesian grid with ghost cell immersed boundary method for arbitrarily complex geometries is developed. A ghost cell immersed boundary treatment with the modification of normal velocity is presented. The method is validated versus well documented test problems involving both steady and unsteady compressible flows through complex bodies over a wide range of Mach numbers. The numerical results show that the present boundary treatment to some extent reduces the error of entropy and demonstrate the efficiency, robustness, and versatility of the proposed approach. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
123.
Two existence theorems of the solutions are obtained for the p-Laplacian systems at resonance under a Landesman-Lazer-type condition by critical point theory. 相似文献
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126.
We described the design and synthesis of a colorimetric and ratiometric fluorescent probe based on a conjugated π-electron system that displayed differential fluorescence responses towards cyanide and sulfide and demonstrated its utility in intracellular ion imaging and logic gate. 相似文献
127.
Molecular bulks are favorable for the thermal and morphological stability in organic wide-bandgap semiconducting polymers with potential applications in both information and energy electronics. In this review, we present our progress in the design of fluorene-based bulky semiconductors with a fractal four-element pattern. Firstly, we established one-pot methods to spirofluorenes, especially spiro[fluorene-9,9′-xanthene](SFX) serving as the next-generation spiro-based semiconductors. Secondly, we observed the supramolecular forces at the bulky groups and discovered the supramolecular steric hindrance(SSH) effect on polymorphisms, nanocrystals as well as device performance. Thus, a synergistically molecular attractor-repulsor theory(SMART) was proposed for the control of nanocrystal morphology, thin film phase and morphology. Thirdly, the third possible type of defects has been identified to generate green band(g-band) emission in widebandgap semiconductors by the introduction of molecular strain design of cyclofluorene. Finally, the first bulky polydiarylfluorene with highly crystalline and β conformation was achieved by an attractor-repulsor design of tadpole-shape monomer, which offered an effective platform to fabricate stable wide-bandgap semiconducting devices. All the discoveries offer the solid basis to break through bottlenecks of organic/polymer wide-bandgap semiconductors by the improvements of overall performances. 相似文献
128.
In this article, polymer network liquid crystal (PNLC) grating/Fresnel lens is fabricated by holography. The exposure light pattern for the grating is obtained by interfering two planar wave fronts, while the Fresnel pattern is achieved by interfering a planar wave front and a spherical wave front. Owing to the alignment effect and anchoring power of polymer network, the holographic PNLC grating achieves improved diffraction efficiency, and remarkably reduced operation voltage (reduced by 80%) compared with holographic polymer-dispersed-liquid-crystal and holographic polymer-stabilised blue-phase liquid-crystal gratings, while maintaining submillisecond response. Moreover, it achieves high spatial frequency with a 2-μm grating period, thanks to the holographic fabrication. The holographic PNLC Fresnel lens also exhibits attractive electro-optical properties. 相似文献
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130.
Xiao-bin Liao Yu-fang Guo Jian-hua He Wei-jian Ou Dai-qi Ye 《Plasma Chemistry and Plasma Processing》2010,30(6):841-853
A method based on high performance liquid chromatography (HPLC), has been developed to measure hydroxyl radical (·OH) in plasma reactors. The determination was performed indirectly by detecting the products of the reaction of ·OH with salicylic acid (SAL). The applicability, and effect of time, specific input energy (SIE), relative humidity (RH),
catalyst were investigated. It was found that 3 h was the optimal trapping time; concentration of ·OH was (5.9–23.6) × 1013 radicals/cm3 at SIE range. The highest ·OH yield and toluene removal efficiency (η) were achieved with a RH of 20%. With MnO
x
, η was two times that without catalyst, while ·OH yield in gas stream was one-sixth that without catalyst. However, if summed with ·OH adsorbed on catalyst surface, the total ·OH yield was the same as without catalyst. Experiments performed with/without toluene allowed to determine the role of ·OH on decomposition of toluene in air plasma. 相似文献