The second-order nonlinear differential equations are studied and the existence of the periodic degeneratesolution is proved with the principle of the functional analysis.
应用非线性泛函分析的理论和方法研究了一类二阶线性微分方程，证明了周期衰减解的存在性。
2
In this paper, the first experiment of generating the phase conjugated backward wave by degenerate four-wave mixing in chlorophyll solution is reported.
本文报道在叶绿素溶液中用简并的四波混频得到位相复共轭后向反射波的首次实验。
3
This paper is concerned with the decay rates of the solution to the strong planar rarefaction waves for scalar conservation laws with degenerate viscosity in several space dimensions.