With the character of history,individuality and stage,the qualitative time is more important than quantitative time in individual teacher s development and becomes the synthetic representation of the quality of individual life.

In this paper the authors study the large time behavior for the weak solution of the nonlinear evolution equation in the whole space and the half space and prove that the solution decays in L~2 norm at t~~~(-n2(1r-12)) and t~~~(-n2(1r-12)-12),respectively, which is the same as the solution of the heat equation.

Species diversity under effects of temporal heterogeneity of habitat destruction;

Mountain ecosystems in arid and semiarid regions are frequently characterized by significant spatial self-organization,and temporal heterogeneity of soil moisture maybe an important driver factor in the vegetation pattern formation and maintenance.