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991.
An analysis is presented for determining the current induced by a known transverse electric excitation on a perfectly conducting cylinder located near the planar interface separating two semi-infinite, homogeneous half-spaces of different electromagnetic properties. The conducting cylinder of general cross section is of infinite extent and the excitation is transverse electric to the cylinder axis. Two types of integral equations, the magnetic field integral equation and the electric field integral equation, are formulated, and the Green's functions for the integral equations are derived in an appendix. Numerical solution methods for solving the integral and integrodifferential equations are presented. For a strip parallel or perpendicular to the interface, a circular cylinder, and a rectangular cylinder, data are presented and discussed for selected parameters, including the case of a cylinder resting on the interface. 相似文献
992.
本文提出了一种新型的耦合器-全息发光二极管-光纤耦合器,进行了理论设计,给出了设计方法及设计结果。结果表明:这种新型的耦合器可显著增加耦合效率。 相似文献
993.
Enhancement of the light emission of CdSe quantum dots was observed by coupling through localized surface plasmons from Au nanoparticles. The enhancement was found to be relative to the shapes and sizes of Au nanoparticles. Au nanoparticles of different sizes were synthesized by a citrate-seeded method. By varying the annealing temperature, worm-like Au nanoparticles of different aspect ratios from 1 to 5 were obtained. Samples of the CdSe coupled with Au with an aspect ratio of 2 and annealed at 500 °C exhibited the best photoluminescence emission efficiency. Furthermore, a stronger photoluminescence enhancement was observed with increasing the size of Au nanoparticles. It was also found that when the localized surface plasmons resonance absorption wavelength of Au nanopartiles was just a little smaller than the emission peak of CdSe, the CdSe quantum dots exhibited the strongest photoluminescence intensity, with an enhancement of 6 times. 相似文献
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997.
Zhao Caiye Yi Xiaolei Hou Qiang Feng Jiajia Zhang Yufeng Xu Mingxiang Shi Zhixiang 《Journal of Superconductivity and Novel Magnetism》2021,34(10):2565-2572
Journal of Superconductivity and Novel Magnetism - In this work, a series of FeS1-xTex (0 ≤ x ≤ 0.15) single crystals were successfully synthesized by a hydrothermal method for the... 相似文献
998.
Sainan Liu Hongtai Shen Jiawei Xu Xiaojun Zhou Jianfei Liu Zhenyang Cai Xiaojun Zhao Lairong Xiao 《材料科学技术学报》2021,81(22):117-122
To develop an ultra-high-temperature resistant coating for a reusable thermal protection system,the preparation of a tantalum-based MoSi2-Mo coating by a new two-step process of multi-arc ion plating and halide activated pack cementation is presented.The coating has a dense structure and is well compatible with the tantalum substrate,which can be thermally shocked from room temperature to 1750℃ for 360 cycles without failure.The mechanism of the coating's excellent resistance to high-temperature thermal shocks is that a strong-binding gradient interface and a dense SiO2 oxide scale with good oxygen resistance are formed by the high-temperature self-diffusion of Si. 相似文献
999.
Jun Cao Tianli Zhang Jinghua Liu Hao Xu Mingyao Hu Wei Xia Ao Wang Hui Wang Chengbao Jiang 《材料科学技术学报》2021,85(26):56-61
Increasing iron content has been witnessed an essential method to improve the remanence of 2:17-type Sm-Co-Fe-Cu-Zr magnets,however,the inferior squareness factor accompanied with the increased iron content turns into a neck sticking problem.In this work,the grain boundary optimization induced sub-stantial squareness enhancement from 63.4%to 91.4%,and consequently an excellent maximum energy product of 32.63 MGOe have been achieved in iron-rich Sm-Co-Fe-Cu-Zr magnets via tuning solution process.It is clearly revealed that the grain boundary(GB)phases as well as the micro-twins'density in grain interiors can be controlled and interprets the enhancement mechanism of squareness. 相似文献
1000.
Song Juan-Juan He Bin Wang Xinchao Guo Yueqi Peng Chunqing Wang Yang Su Zhi Hao Qingli 《Journal of Materials Science》2021,56(30):17178-17190
Journal of Materials Science - Controlling the morphology of metal–organic frameworks to improve their application in energy storage remains a particular challenge. In this work, hollow... 相似文献