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71.
L Hai-Jiang YE Yun-Xiu YAN Xin-Hu CHENG He-Ping JIAO Zheng HE Ju LIU Ren-Chen 《中国物理C(英文版)》2008,32(8)
In the GDH sum rule measurement in JLab Hall-A,to obtain the cross section of electron scattering on polarized 3He and its asymmetry in different helicity states,the dilution effect from unpolarized nitrogen mixed in the polarized 3He target were calculated at different kinematic settings. 相似文献
72.
Ternary subdivision schemes compare favorably with their binary analogues because they are able to generate limit functions with the same (or higher) smoothness but smaller support.In this work we consider the two issues of local tension control and conics reproduction in univariate interpolating ternary refinements. We show that both these features can be included in a unique interpolating 4-point subdivision method by means of non-stationary insertion rules that do not affect the improved smoothness and locality of ternary schemes. This is realized by exploiting local shape parameters associated with the initial polyline edges. 相似文献
73.
In this work we demonstrate that non-symmetrically substituted phthalo-naphthalocyanine molecule can have extremely large 2PA cross section in near-resonance conditions of excitation. We also show the possibility to switch between its two tautomeric forms upon two-photon excitation at 77 K. By measuring 2PA cross section, quantum efficiency of transformation in these two forms, as well as quantum yield of fluorescence, we evaluate the figure of merit for fast re-writable 3D information storage and show that this figure meets the criteria of reliable and fast (one bit per one femtosecond pulse) 2PA writing or reading. 相似文献
74.
75.
F. F. Gong F. X. Gong F. Y. Gong 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,49(3):267-268
Open dynamic behaviour of financial markets with internal
interactions between agents and with external “fields” from other systems
are investigated using the approach of Grossman and Stiglitz for inefficient
markets, and Keynes for interference of the market using physics of finance
(referred to hereafter as phynance). The simulation results indicate that
the NYSE data analyzed in Plerou, V. et al., Nature 421, 130 (2003) can be fitted
by an equation of order parameter Φ and local deviation R of type:
-(R+0.03) Φ+ 0.6 Φ3 + 0.02 = 0, which is shown to be in
remarkable agreement with Plerou's data. 相似文献
76.
Elastic electron scattering with formamide-(H2O)n complexes (n=1, 2): Influence of microsolvation on the π* and σ* resonances 下载免费PDF全文
Kedong Wang 《中国物理 B》2021,30(12):123401-123401
We report elastic cross sections for low-energy electron scattering with formamide-(H2O)n complexes (n=1, 2) in the energy region of 0.01-8 eV. The scattering calculations are performed using the R-matrix method in the static-exchange (SE) approximation. We consider three structures of formamide-H2O and six structures of formamide-(H2O)2 in the present work. Our purpose is to investigate effects of water molecules hydrogen-bonding to formamide. We focus on the influence of microsolvation on the π* and σ* resonances of formamide. The scattering result for complexes shows that the position of π* resonance appears at lower or higher energies in the cluster than in the isolated formamide depending on the complex structure and the water role in the hydrogen bonding. We explain this behavior according to the net charge of the solute. It is found that the microsolvation environment has a substantial effect on the width of π* resonance. Our results indicate that surrounding water molecules may affect the lifetime of the resonances, and hence the process is driven by the anion state, such as the dissociative electron attachment. 相似文献
77.
Quantum reaction dynamics of C(1D) + HD → CH(CD) + D(H) on the ground state potential energy surface 下载免费PDF全文
We present accurate quantum dynamic calculations of the reaction C(1D) + HD on the latest version of the potential energy surface [Zhang et al., J. Chem. Phys. 140, 234301 (2014)]. Using a Chebyshev real wave packet method with full Coriolis coupling, we obtain the initial state‐specified ( ) reaction probabilities, integral cross sections, and rate constants. The resulting probabilities display oscillatory structures due to numerous long‐lived resonances supported by the deep potential well. The calculated rate constants and CD/CH product branching ratio at room temperature are in reasonably good agreement with the experimental measurements. 相似文献
78.
Global X2A′ potential energy surface of Li2H and quantum dynamics of H + Li2 (X1Σg+) → Li + LiH (X1Σ+) reaction 下载免费PDF全文
A global potential energy surface (PES) for the electronic ground state of Li2H system is constructed over a large configuration space. About 30 000 ab initio energy points have been calculated by MRCI‐F12 method with aug‐cc‐pVTZ basis set. The neural network method is applied to fit the PES and the root mean square error of the current PES is only 1.296 meV. The reaction dynamics of the title reaction has been carried out by employing time‐dependent wave packet approach with second order split operator on the new PES. The reaction probability, integral cross section and thermal rate constant are obtained from the dynamics calculation. In most of the collision energy regions, the integral cross sections are in well agreement with the results reported by Gao et al. The rate constant calculated from the new PES increases in the temperature range of present investigation. 相似文献
79.
对“求圆截线平面问题”作了深入研究,给出了四种解法,得到了与椭球面交线是圆的平面的充分必要条件,交线圆的中心和半径,并结合该问题谈了基础课教学中对学生能力的培养. 相似文献
80.