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131.
Based on the differential forms and exterior derivatives of fractional orders,Wu first presented the generalized Tu formula to construct the generalized Hamiltonian structure of the fractional soliton equation.We apply the generalized Tu formula to calculate the fractional Dirac soliton equation hierarchy and its Hamiltonian structure.The method can be generalized to the other fractional soliton hierarchy.  相似文献   
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133.
Based on the concepts of fast polarization,effective electric field and electron impact ionization criterion,the effect of polymer type on electric breakdown strength(E BD) on a nanosecond time scale is investigated,and a formula that qualitatively characterizes the relation between the electric breakdown strength and the polymer type is derived.According to this formula,it is found that the electric breakdown strength decreases with an increase in the effective relative dielectric constants of the polymers.By calculating the effective relative dielectric constants for different types of polymers,the theoretical relation for the electric breakdown strengths of common polymers is predicted.To verify the prediction,the polymers of PE(polyethylene),PTFE(polytetrafluoroethelene),PMMA(organic glass) and Nylon are tested with a nanosecond-pulse generator.The experimental result shows E BD(PTFE) > E BD(PMMA) > E BD(Nylon) > E BD(PE).This result is consistent with the theoretical prediction.  相似文献   
134.
The P-branch emission spectra of (4,1) and (3,1) bands of the A~1π-X~1Σ~+ system of IrN molecule are studied using an analytical formula which is derived from elementary expression of molecular total energy by taking multiple spectral differences.It not only reproduces the known experimental transition lines,but also predicts the unknown spectral lines up to J=80 for each band by using a group of fifteen known experimental transition lines.  相似文献   
135.
Stretched polymers will lose their possible configurations if they are mixed with nanoparticles or touch a hard wall,which leads to a strong depletion attraction responsible for the enrichment of nanoparticles near substrates.Moreover,it is found that there exists a sacrifice mechanism in confined pure polymer samples or polymer-nanoparticle mixtures,that part of the polymers,in order to reach a minimum free energy for the total system,are adsorbed on hard walls even though they lose their conformation.The current study provides a simple yet effective approach for the design of thin polymer composites.  相似文献   
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