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Schmitt trigger is a comparator circuit with hysteresis, implemented by applying positive feedback to a noninverting input. Recently, it has been verified that noise under certain condition can help nonlinear circuit to realize reliable logical stochastic resonance (LSR). In this letter, we demonstrate that, without any modifications, Schmitt trigger can operate flexibly both as logic operation and latch operation in an optimal noise range. In traditional Schmitt trigger, the hysteresis is designed for resisting noise. In the new design, the hysteresis tends to enhance the LSR effect in Schmitt trigger with the help of noise and helps the system to perform better at higher noise levels. Thus, our results extend the application scope and generality of the traditional Schmitt trigger. 相似文献
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A palladium-catalyzed desulfitative conjugate addition of sodium sulfinates with α,β-unsaturated carbonyl compounds is described. The reaction showed very good selectivity and tolerated a wide range of functionalities under an atmosphere of argon. 相似文献
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An unusual direct amidation of alcohols with nitroarenes mediated by peroxides has been discovered. The reaction tolerated a wide range of functionalities, and various aromatic amides were obtained in moderate to good yields in the absence of transition-metal catalyst. The peroxides and solvents had a significant impact on the reaction yield. 相似文献
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Analysis of generalized projective synchronization for a chaotic gyroscope with a periodic gyroscope
Fuhong Min 《Communications in Nonlinear Science & Numerical Simulation》2012,17(12):4917-4929
In this paper, a simple nonlinear controller is applied to investigate the generalized projective synchronization for a controlled chaotic gyroscope with a periodic gyroscope dynamical system. The necessary and sufficient conditions for generalized projective synchronization are developed through the theory of discontinuous dynamical systems. The synchronization invariant domain from the synchronization conditions is presented. The parameter maps are explored for a better understanding of the synchronicity of two gyroscopes with different motions. Finally, the partial and full generalized projective synchronizations of two nonlinear coupled gyroscope systems are carried out to verify the effectiveness of the scheme. 相似文献
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In this paper, the analytical conditions for a periodically forced Duffing oscillator synchronized with a chaotic pendulum are developed through the theory of discontinuous dynamical systems. From the analytical conditions, the synchronization invariant domains are developed. For a better understanding of synchronization of two different dynamical systems, the partial and full synchronizations of the Duffing oscillator with the chaotic pendulum are presented for illustrations. The control parameter map is developed from the analytical conditions. Under special parameters, the two systems can be fully and partially synchronized. Since the forced pendulum has librational and rotational chaotic motions, the periodically forced Duffing oscillator can be synchronized only with the librational chaotic motions of the pendulum. It is impossible for the forced Duffing oscillator to be synchronized with the rotational chaotic motions. 相似文献
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Powders of the Nasicon material NaTi2(PO4)3 were directly synthesized at ultra-low temperature. NaTi2(PO4)3 was obtained by mixing the initial reagents titanium hydroxide, 85 % H3PO4, and NaH2PO4·2H2O at 85 °C for 3.5 h or at 125 °C for 1.5 h. The raw materials and synthesized products were characterized for purity, crystal structure, particle size, and powder morphology by thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy, scanning electron microscopy (SEM), and UV–visible diffuse reflectance spectroscopy. XRD results revealed that NaTi2(PO4)3 powders with rhombohedral crystal structure were synthesized at 85 and 125 °C. SEM patterns showed that the as-prepared products were agglomerated and that each of the agglomerations consisted of many small grains 50–80 nm in diameter. 相似文献
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Let and be two integers with and . For a graph and a vertex of , we use to denote the degree of in . Define to be the minimum value of , where is an independent set of with . This paper proves the following conjecture proposed by Gould et al. (2018). If is a graph of sufficiently large order with , then contains vertex-disjoint cycles. 相似文献
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Nonlinear Dynamics - The present paper investigates coordinated oscillatory motion of networked Lagrangian systems under diverse interactions. Based on two new auxiliary oscillator systems, we... 相似文献
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A highly selective phosphine-based ruthenium catalyst system efficiently catalyzes the direct amination of alcohols with aliphatic tertiary amines, yielding unsymmetric tertiary amines in yields up to 87%. Ligand and solvent both affect the reaction yields significantly. The reaction can be performed with a wide variety of functionalities. 相似文献