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611.
G. Solís-Perales E. Ruiz-Velázquez D. Valle-Rodríguez 《Communications in Nonlinear Science & Numerical Simulation》2009,14(6):2528-2535
We present an approach to the chaos synchronization of complex networks with distinct nodes. The chaotic synchronization is achieved by adding a derivative coupling term in the network equation. We assume that node in networks are different and are given by the Lorenz, Rössler, Chen and Sprott chaotic systems. The derivative term is capable to induce the synchronous behavior in the network. Moreover such a coupling leads the global behavior to a chaotic attractor. We found that without derivative coupling the network is leaded only to an equilibrium point or a limit cycle. Numerical simulations are provided to illustrate the result. Complementary the network synchrony can be chaotic in presence of the derivative coupling. 相似文献
612.
L. de Viguerie A. Duran A. Bouquillon V. A. Solé J. Castaing P. Walter 《Analytical and bioanalytical chemistry》2009,395(7):2219-2225
The X-ray fluorescence (XRF) technique is a common choice in the archaeometric field for in situ investigations with portable
instruments. This work shows that XRF portable systems can be used for quantitative analyses using appropriate software, obtaining
a similar accuracy to that provided with other techniques such as particle-induced X-ray emission (PIXE), as shown for an
Egyptian faience pendant and for two glass standards. 相似文献
613.
A surface integral equation together with the multilevel fast multipole algorithm is successfully applied to fast and accurate resolution of plasmonic problems involving a large number of unknowns. The absorption, scattering, and extinction efficiencies of several plasmonic gold spheres of increasing size are efficiently obtained solving the electric and magnetic current combined-field integral equation. The numerical predictions are compared with reference analytic results to demonstrate the accuracy, suitability, and capabilities of this approach when dealing with large-scale plasmonic problems. 相似文献
614.
7-Ethyl-4,7-dihydro-4-oxo-2-(4-pyridinyl)thieno[2,3-b]pyridine-5-carboxylic acid ( 4 ), an analog of nalidixic acid, was synthesized in seven steps starting from commercially available 4-methylpyridine. Bacterial susceptibility to compound 4 was tested and the title compound was found to exhibit only weak antibacterial activity against a variety of pathogens including S. Aureus, E. Coli and P. Aeruginosa. 相似文献
615.
Enric Sabater Miquel Solà Pedro Salvador Diego M. Andrada 《Journal of computational chemistry》2023,44(3):268-277
The classic pnictogen dichotomy stands for the great contrast between triply bonding very stable N2 molecules and its heavier congeners, which appear as dimers or oligomers. A banner example involves phosphorus as it occurs in nature as P4 instead of P2, given its weak π-bonds or strong σ-bonds. The P2 synthetic value has brought Lewis bases and metal coordination stabilization strategies. Herein, we discuss the unrealized encapsulation alternative using the well-known fullerenes' capability to form endohedral and stabilize otherwise unstable molecules. We chose the most stable fullerene structures from Cn (n = 50, 60, 70, 80) and experimentally relevant from Cn (n = 90 and 100) to computationally study the thermodynamics and the geometrical consequences of encapsulating P2 inside the fullerene cages. Given the size differences between P2 and P4, we show that the fullerenes C70–C100 are suitable cages to side exclude P4 and host only one molecule of P2 with an intact triple bond. The thermodynamic analysis indicates that the process is favorable, overcoming the dimerization energy. Additionally, we have evaluated the host-guest interaction to explain the origins of their stability using energy decomposition analysis. 相似文献