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51.
The photodissociation dynamics of isocyanic acid (HNCO) has been studied by the timesliced velocity map ion imaging technique at 193 nm. The NH(a1Δ) products were measured via (2+1) resonance enhanced multiphoton ionization. Images have been accumulated for the NH(a1Δ) rotational states in the ground and vibrational excited state (v=0 and 1). The center-of-mass translational energy distribution derived from the NH(a1Δ) images implies that the CO vibrational distributions are inverted for most of the measured 1NH(v|j) internal states. The anisotropic product angular distribution observed indicates a rapid dissociation process for the N-C bond cleavage. A bimodal rotational state distribution of CO(v) has been observed, this result implies that isocyanic acid dissociates in the S1 state in two different pathways. 相似文献
52.
53.
We study the H+CH4/CD4→H2/HD+CH3/CD3 reactions using the time sliced velocity map ion imaging technique. Ion images of the CH3/CD3 products were measured by the (2+1) resonance enhanced multi-photon ionization (REMPI) detection method. Besides the CH3/CD3 products in the ground state, ion images of the vibrationally excited CH3/CD3 products were also observed at two collision energies of 0.72 and 1.06 eV. It is shown that the angular distribution of the products CH3/CD3 in vibrationally excited states gradually vary from backward scattering to sideways scattering as the collision energy increases. Compared to the CH3/CD3 products in the ground state, the CH3/CD3 products in vibrationally excited states tend to be more sideways scattered, indicating that larger impact parameters play a more important role in the vibrationally excited product channels. 相似文献
54.
This article is concerned with Markov chains on m constructed by randomly choosing an affine map at each stage, and then making the transition from the current point to its image under this map. The distribution of the random affine map can depend on the current point (i.e., state of the chain). Sufficient conditions are given under which this chain is ergodic. 相似文献
55.
Kung-Chien Wu 《Journal of Mathematical Analysis and Applications》2010,365(2):584-589
This paper is devoted to the proof of the convergence from the modulated cubic nonlinear defocusing Klein-Gordon equation with magnetic field to the wave map equation. More precisely, we discuss the nonrelativistic-semiclassical limit of the modulated cubic nonlinear Klein-Gordon equation with magnetic field where the Planck's constant ?=ε and the speed of light c are related by c=ε−α for some α?1. When α=1 the limit wave function satisfies the wave map with one extra term coming from the magnetic field. However, α>1, the effect of the magnetic filed disappears and the limit is the typical wave map equation only. 相似文献
56.
In this paper we design and implement rigorous algorithms for computing symbolic dynamics for piecewise-monotone-continuous maps of the interval. The algorithms are based on computing forwards and backwards approximations of the boundary, discontinuity and critical points. We explain how to handle the discontinuities in the symbolic dynamics which occur when the computed partition element boundaries are not disjoint. The method is applied to compute the symbolic dynamics and entropy bounds for the return map of the singular limit of a switching system with hysteresis and the forced Van der Pol equation. 相似文献
57.
定义了H~2×R中曲面的法高斯映照,给出了给定平均曲率曲面的Weierstrass表示,证明了法高斯映照满足一个二阶偏微分方程,并且该方程是所得到的Weierstrass表示的完全可积条件. 相似文献
58.
Let f:I→I be a unimodal map on I without homtervals. We characterize the α-limit set of each point in I by considering the consecutive renormalization process of f. 相似文献
59.
运用分支函数的方法研究了Logistic映射出现稳定三周期点的参数窗口,借助软件Singular 2.0.3运用多元多项式的Grobner基并结合严格局部分析的方法给出Logistic映射出现稳定三周期点时的参数值范围,最后数值模拟方法对所得的结果进行了验证,并指出伪轨现象. 相似文献
60.