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41.

By introducing a memristor into a chaotic system with a single non-quadratic term and substituting an absolute value function for conditional symmetry, a unique chaotic system is constructed. Firstly, the system shares a special structure of symmetry and conditional symmetry. Secondly, the amplitude and frequency of the system variables can be rescaled by the applied memristor. Interestingly it gives a new case of attractor control namely partial amplitude control and global frequency control. At last, as a new regime of extreme multistability, the memristive system shows relatively simple bifurcation according to the initial condition. This new class of chaotic system has never been reported to the best of our knowledge.

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Li  Kezan  Yu  Wenwu  Ding  Yong 《Nonlinear dynamics》2015,80(1-2):421-430
Nonlinear Dynamics - Successive lag synchronization (SLS) is defined as a new synchronization pattern, which means that lag synchronization appears between two successively numbered nodes in a...  相似文献   
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A sensitive and simple liquid chromatography–tandem mass spectrometric (HPLC‐MS/MS) method for the determination of corilagin in rat plasma has been developed. Samples were prepared with protein precipitation method and analyzed with a triple quadrupole tandem mass spectrometer. We employed negative electrospray ionization as the ionization source and the analytes were detected in multiple reaction monitoring mode. Separation was achieved on a C8 column eluted with mobile phase consisting of methanol–0.1% formic acid in a gradient mode at the flow rate of 0.3 mL/min. The total run time was 7.0 min.This method was proved to have good linearity in the concentration range of 2.5–1000.0 ng/mL. The lower limit of quantification of corilagin was 2.5 ng/mL. The intra‐ and inter‐day relative standard deviationa across three validation runs for four concentration levels were both <9.8%. The relative error was within ±6.0%. This assay offers advantages in terms of expediency and suitability for the analysis of corilagin in rat plasma. The practical utility of this new HPLC‐MS/MS method was confirmed in pilot plasma concentration studies in rats following oral administration. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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《Mendeleev Communications》2019,29(3):256-259
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Using first principles density functional theory, we predict a monolayer B2Si structure with space group Pmm2 in the present work. This structure is confirmed to be dynamically stable. Based on the plane wave pseudopotential approach, the charge density, electron localization function, density of states, energy band, phonon property and thermal conductivity of Pmm2-B2Si are systematically studied. It is interesting that the sp2 hybridization and coordination bond of Si are found in Pmm2-B2Si, which is the most important factor for its structural stability. The density of states and energy band analysis reveals that Pmm2-B2Si is metallic because of the partial occupied Si 3pz and B 2pz states. Moreover, the acoustic-optical coupling is important for phonon transport in Pmm2-B2Si, and the contribution of optical modes to the lattice thermal conductivity along the [100] and [010] directions is 13% and 12%, respectively. This study gives a fundamental understanding of the structural, electronic and phonon properties in Pmm2-B2Si.  相似文献   
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