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1.
Abstract A novel and simple two-frequency Brillouin fiber laser is presented. It is based on a fiber Fabry-Perot cavity with fiber Bragg gratings as reflectors. The model of stimulated Brillouin scattering in fiber grating–based Fabry-Perot resonator is investigated. The laser allows conversion efficiency of close to 100% and suppresses the higher-order Stokes waves. The theoretical prediction is presented and the experimental demonstration is realized. 相似文献
2.
刘康生 《广东微量元素科学》1998,5(7):59-60
采用自拟的降脂方治疗血胆增高患者63人,并与用月见草油胶丸治疗患者61人比较,前者疗效优于后者,两组有显著性差异。 相似文献
3.
Wenzhi Wang Langyuan Wu Zhiwei Li Kangsheng Huang Ziyang Chen Chen Lv Prof. Hui Dou Prof. Xiaogang Zhang 《ChemElectroChem》2021,8(11):2014-2021
Residual lithium on the surface and the resulting side reactions for high-energy-density Ni-rich layered oxide cathodes principally impede their industrial application and trigger safety concerns. Herein, the successful construction of LiBO2−B2O3 co-modified single-crystal LiNi0.6Co0.2Mn0.2O2 (SC-NCM) as a lithium-ion battery (LIB) cathode is reported. Boric acid reacts with the surface residual lithium species to form such uniform coating on the SC-NCM particles, which presents advanced rate and cycling capabilities. As the cathode materials for LIBs, LiBO2−B2O3 co-modified SC-NCM delivers a 141.9 mAh g−1 discharge specific capacity at 5 C between 3.0 and 4.5 V versus Li+/Li with 61.4 % capacity retention after 500 cycles, superior to the 20.8 % retention for the pristine SC-NCM cathode. Besides, the LiBO2-B2O3 protective layer substantially inhibits the unexpected phase transformation, effectively alleviates the mechanical microcracks, and stabilizes the cathode-electrolyte interface, even at an extended operational potential window. The proposed microstructure-modified SC-NCM cathode provides an affordable and feasible design strategy for Ni-rich SC-NCM cathodes towards stable electrochemical performance and prolonged service life at high potential. 相似文献
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Guowu Zheng Kangsheng Chen 《International Journal of Infrared and Millimeter Waves》1992,13(10):1599-1608
In this paper, the transient responses of microstrip containing ferrite dielectric layers are studied by using extended FD-TD method. When the microwave signal propagating along the microstrip is comparable with the applied DC magnetic field on the ferrite, the nonlinearity of ferrite medium is represented. The propagating procedure of Gaussian pulse in the microstrip are simulated. It is shown that the effects of the pulse amplitude on the transmission distortion of Gaussian pulse is pronounced. 相似文献
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This paper concerns the regularity of a functional differential equation in the form: , t>0, where A is the generator of an analytic semigroup on a Banach space X, and B1,B2 are α(γ−A)-bounded linear operator for 0<α<1. By spectral analysis, it is shown that the associated solution semigroup of this equation is eventually differentiable. 相似文献
10.
空间几何构造分析的有限单元法 总被引:2,自引:0,他引:2
提出空间杆系几何构造分析的有限单元法,构造了两种单元(链杆单元和准梁单元)的几何约束矩阵,集成为整体矩阵并引入承条件后,通过对其阶数与秩的比较分析确定体系的几何可变性及静定性.本法原理简单,便于计算机实施,结果完备:对于几何不变体系,可指出多余约束的数目;对于几何可变体系,可给出体系的自由度数及相应的运动模态,并确定自由度的常变瞬变性质. 相似文献