Blow Up And Extinction For A Class Of Sixth-order Parabolic Equation

In this thesis,we consider the initial-boundary-value problem for a class of sixth-order parabolic equation(?)The aim of this work is to establish the conditions that identify finite time blow-up or the global existence to the solutions of the problem.First,we combine the potential well method,the classical Galerkin method and the energy method to give a threshold result for the global existence and non-existence of sign-changing weak solutions to the problem.Next,we discuss the extinction properties and asymptotic behavior of the global solutions.Further,we obtain the lower bound and upper bound of blow-up time.