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This paper establishes several criteria of stability for nonlinear differential dynamical systems relative to initial time difference by employing perturbing Lyapunov functions. The reported novel results are more easy to be tested than the existing results. As an application, these results are applied to a nonlinear dynamical system to get the stability properties relative to initial time difference. 相似文献
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Tianxue Li Zhixiang Yan Chen Zhou Jian Sun Chuan Jiang Xinghao Yang 《Biomedical chromatography : BMC》2013,27(8):1041-1053
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Jianglong Li Dongsheng Lu Zhixiang Chen Huanna Zeng Aiju Li Yuepeng Cai 《Ionics》2017,23(9):2275-2283
In this wok, a series of LiNi0.5Mn1.5O4 (LNMO) samples with an octahedral shape entirely composed of (111) crystal planes were prepared by calcining the mixture of the precursor Ni0.25Mn0.75(OH)2 and LiOH·H2O at 800 °C for 15 h in air, followed by annealing them at 600 °C for different dwelling times. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and several electrochemical technologies were used to investigate the effect of annealing time on properties of the LNMO samples. XRD analysis indicates that the lattice parameters of the LNMO samples show a decreasing trend with increasing of annealing time, and the impurity peaks become less apparent for the sample annealed for 6 h and almost disappear for the samples annealed for 9 and 24 h. SEM results show that the annealing time has no obvious influence on the morphologies of the LNMO samples. Electrochemical measurements show that the electrochemical performances (capacity, cycle life, and rate capability) of the samples annealed for 6, 9, and 24 h are better than those of the unannealed sample, and the sample annealed for 9 h shows the best electrochemical properties among them due to its superior electrochemical kinetics of Li+ insertion/desertion. 相似文献