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141.
As a continuation of part I of the paper under the same title, we developgeneral monotonic enclosure methods for the couple systems of the splitting equations {x=G([x]a,[x]b,[y]c) y=G([y]a,[y]b,[x]c),which models the system of equations associated with hybrid and aaynchronotts monotonicity as well as convexity. The resulting algorithms and convergence theorems generalize and unify various known methods and monotonic enclosure theorents established by other authors. 相似文献
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Hong-Shuo Li J. M. Cadogan Jian-Min Xu S. X. Dou H. K. Liu 《Hyperfine Interactions》1994,94(1):1929-1935
A study of the Nd-Fe-Ti phases at the Fe-rich end of the phase diagram has been carried out using57Fe Mössbauer spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). In particular,57Fe Mössbauer spectroscopy has been used to characterize the phases present in these samples. In addition to the two well-known 217 and 112 phases, twonovel phases have been identified, with compositions denoted by3–29 and9–94, which are closely linked to the orthorhombic ScFe6Ga6-type and the hexagonal TbCu7-type structures, respectively. The possible crystal structures of these new phases will be discussed in terms of the dumbbell substitution sequence in the CaCu5 structure. 相似文献
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147.
Origin and manifestation of the anharmonic potential felt by an ion-cloud in an actual Paul trap 总被引:1,自引:0,他引:1
X. Luo X. Zhu K. Gao J. Li M. Yan L. Shi J. Xu 《Applied physics. B, Lasers and optics》1996,62(4):421-426
The anharmonic potential felt by a single-species ions confined in a rf quadrupole trap which results from a non-ideal trap configuration and the charge distribution of the ion cloud is studied. The rf resonance-absorption spectra are explained by a Duffing oscillator and a representation of the line-shape parameter is derived. For > 0.77, the electric signals will exhibit hysteresis. The relation with the anharmonic potential is discussed. 相似文献
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Lijun Zhang Shanjia Xu 《International Journal of Infrared and Millimeter Waves》1996,17(10):1735-1747
The finite element method is combined with the mode-matching method and the multi-mode network method to analyze the scattering and radiation characteristics of a class of planar dielectric waveguide discontinuities. Unlike the conventional method to treat the radiation as a source-field problem, in the present approach, the dispersion characteristics of dielectric guided-wave structures are calculated first, and then the radiation problem is transferred to the propagation problem of a series of surface-waves and space waves from the viewpoint of scattering, thus the analysis is tremendously simplified. 相似文献