Open Access Research

A note on blow-up of solutions for the nonlocal quasilinear parabolic equation with positive initial energy

Zhong Bo Fang*, Lu Sun and Changjun Li

Author Affiliations

School of Mathematical Sciences, Ocean University of China, Qingdao, 266100, P.R. China

For all author emails, please log on.

Boundary Value Problems 2013, 2013:181  doi:10.1186/1687-2770-2013-181


The electronic version of this article is the complete one and can be found online at: http://www.boundaryvalueproblems.com/content/2013/1/181


Received:2 March 2013
Accepted:23 July 2013
Published:8 August 2013

© 2013 Fang et al.; licensee Springer

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

In this short note, we consider a nonlocal quasilinear parabolic equation in a bounded domain with the Neumann-Robin boundary condition. We establish a blow-up result for a certain solution with positive initial energy.

1 Introduction

We consider the initial boundary value problem for a nonlocal quasilinear parabolic equation

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M1','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M1">View MathML</a>

(1.1)

with Neumann-Robin boundary and initial conditions

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M2','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M2">View MathML</a>

(1.2)

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M3','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M3">View MathML</a>

(1.3)

where <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M4','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M4">View MathML</a> (<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M5','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M5">View MathML</a>) is a bounded domain with a smooth boundary, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M6','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M6">View MathML</a> denotes the Lebesgue measure of the domain Ω, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M7','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M7">View MathML</a> with <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M8','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M8">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M9','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M9">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M10','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M10">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M11','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M11">View MathML</a>, and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M12','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M12">View MathML</a>. It is easy to check that the integral of u over Ω is conserved. Meanwhile, since <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13">View MathML</a> is not required to be nonnegative, we use <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M14','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M14">View MathML</a> instead of <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M15','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M15">View MathML</a> in equation (1.1).

Equation (1.1) arises naturally from the fluid mechanics, biology, and population dynamics. In particular, it is a possible model for the diffusion system of some biological species with a human-controlled distribution, in which <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M17','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M17">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M14','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M14">View MathML</a>, and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M19','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M19">View MathML</a> represent the density of the species, the mutation, which we may view as the spread of the characteristic, the growth source of the species, and the human-controlled distribution at position x and time t, respectively. The arising of a nonlocal term denotes the evolution of the species at a point of space, which depends not only on nearby density, but also on the mean value of the total amount of species due to the effects of spatial inhomogeneity, see [1-3]. This equation can be also used to describe the slow diffusion of concentration of non-Newton flow in a porous medium or the temperature of some combustible substance (cf.[4-6]). In addition, when <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M20','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M20">View MathML</a> in (1.1), equation (1.1) becomes

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M21','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M21">View MathML</a>

which is one of the simplest equations with nonlocal terms and a homogeneous Neumann boundary condition, and the quantity <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M22','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M22">View MathML</a> is conserved. This equation is also related to the Navier-Stokes equation on an infinite slab, which is explained in [7].

In recent years, blow-up theory for solutions of the initial boundary value problem of parabolic equations with local or nonlocal term has been rapidly developed, and there have been many delicate results. Especially, for the relations between initial energy and blow-up solution, see [8-14]. As for researches on the initial boundary value problem of semilinear parabolic equations, we refer the readers to [8-12]. For instances, Hu and Yin [8] considered the nonlocal semilinear equation

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M23','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M23">View MathML</a>

(1.4)

with a homogeneous Neumann boundary condition

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M24','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M24">View MathML</a>

(1.5)

and established a result of local existence for the negative initial energy by using a convexity argument. Soufi [9] investigated a similar problem and established a relation between the finite time blow-up of solutions and the negativity of initial energy for <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M25','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M25">View MathML</a> by using a gamma-convergence argument. They also conjectured that the relation might hold for all <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M26','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M26">View MathML</a>, and a positive answer to which was given by Jazar in [10]. Lately, by using the energy method, Gao [11] established a relation between the finite time blow-up of solutions and the positivity of initial energy of problem (1.4)-(1.5). In addition, Niculescu and Rovenţa [12] considered a more general initial boundary value problem of nonlocal semilinear parabolic equation given by

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M27','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M27">View MathML</a>

with homogeneous Neumann boundary condition (1.5), and established a blow-up result, when <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M28','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M28">View MathML</a> belongs to a large class of nonlinearities and the initial energy was non-positive by using the convexity method. For the initial boundary value problem of quasilinear parabolic equations, Liu and Wang [13] studied the local p-Laplacian equation

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M29','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M29">View MathML</a>

with homogeneous Dirichlet boundary condition, and built a relation between the finite time blow-up of solutions and the positivity of initial energy. Recently, Niculescu and Rovenţa [14] considered the nonlocal quasilinear equation

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M30','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M30">View MathML</a>

with the Neumann-Robin boundary condition (1.2), and established a relation between the finite time blow-up solutions and the negative initial energy, when <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M31','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M31">View MathML</a> and f belongs to a large class of nonlinearities by virtue of a convexity argument.

In those works mentioned above, most problems assumed that the initial energy was negative or non-positive to ensure the occurrence of blow-up. But, to the best of our knowledge, the positive initial energy can also ensure the occurrence of blow-up in local or nonlocal problems. It is difficult to determine whether the solutions of the initial boundary value problem of nonlocal equation (1.1) will blow up in finite time, since the comparison principle, which is the most effective tool to show blow-up of solutions, is invalid. The aim of our work is to find a relation between the finite time blow-up of solutions and the positive initial energy of problem (1.1)-(1.3) by the improved convexity method.

2 Preliminaries and the main result

Since <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M32','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M32">View MathML</a>, equation (1.1) is degenerate on <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M33','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M33">View MathML</a>, there is no classical solution in general. Hence, it is reasonable to find a weak solution of problem (1.1)-(1.3). To this end, we first give the following definition of the weak solution of problem (1.1)-(1.3).

Definition 1 If a function <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13">View MathML</a> satisfies the following conditions:

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M35','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M35">View MathML</a>

where <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M36','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M36">View MathML</a> and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M37','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M37">View MathML</a>, then <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13">View MathML</a> is called a weak solution of problem (1.1)-(1.3).

Remark 1 The existence of local nonnegative solutions in time to problem (1.1)-(1.3) can be obtained by using a fixed point theorem or a parabolic regular theory to get a suitable estimate in a standard limiting process, see [6,15,16]. The proof is standard, and so it is omitted here. Moreover, for convenience, we may assume that the appropriate weak solution is smooth, and no longer consider approximation problem.

Let <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M39','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M39">View MathML</a> denote a subspace of <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M40','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M40">View MathML</a>, and we assume that the functions u in <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M39','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M39">View MathML</a> satisfy <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M42','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M42">View MathML</a>. We also define a norm on <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M39','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M39">View MathML</a> by

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M44','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M44">View MathML</a>

It is easy to see that this norm is equivalent to the classical norm on <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M40','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M40">View MathML</a> by using the Poincaré inequality. Set B be the optimal constant of the embedding inequality

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M46','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M46">View MathML</a>

(2.1)

which is equivalent to

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M47','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M47">View MathML</a>

where

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M48','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M48">View MathML</a>

We also define <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M49','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M49">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M50','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M50">View MathML</a>, and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M51','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M51">View MathML</a> as

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M52','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M52">View MathML</a>

(2.2)

and

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M53','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M53">View MathML</a>

(2.3)

We now introduce our main result on the blow-up solutions with the positive initial energy below.

Theorem 1 (Sufficient condition for blow-up)

Set<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M31','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M31">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M55','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M55">View MathML</a>, when<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M56','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M56">View MathML</a>and<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M57','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M57">View MathML</a>, when<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M58','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M58">View MathML</a>. Suppose that<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M59','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M59">View MathML</a>is a solution of (1.1)-(1.3), and the initial datum<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M60','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M60">View MathML</a>is chosen to ensure that<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M61','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M61">View MathML</a>and<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M62','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M62">View MathML</a>. Then the solution<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13">View MathML</a>blows up in a finite time.

Remark 2 Choose <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M64','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M64">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M65','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M65">View MathML</a> and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M66','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M66">View MathML</a>; one can easily verify that <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M67','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M67">View MathML</a> satisfies <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M60','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M60">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M61','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M61">View MathML</a> and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M62','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M62">View MathML</a>, therefore, conditions in Theorem 1 are valid.

Remark 3 Our result improves the results of Gao [11] and Niculescu and Rovenţa [14].

3 The proof of Theorem 1

To prove our main result, we first establish the following three lemmas obtained by applying the idea of Liu and Wang in [13], where a different type of problem was discussed.

Lemma 1<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M51','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M51">View MathML</a>defined in (2.3) is non-increasing int.

Proof A direct computation with the integration by parts yields

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M72','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M72">View MathML</a>

and hence, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M51','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M51">View MathML</a> is non-increasing in t. □

The following second lemma gives a lower bound estimate for the solution <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M74','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M74">View MathML</a> in the <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M75','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M75">View MathML</a>-norm:

Lemma 2Let<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13">View MathML</a>be a solution of (1.1)-(1.3) with initial data satisfying

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M77','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M77">View MathML</a>

Then there exists a positive constant<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M78','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M78">View MathML</a>such that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M79','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M79">View MathML</a>

(3.1)

and

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M80','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M80">View MathML</a>

(3.2)

Proof By (2.1) and (2.3), we notice that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M81','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M81">View MathML</a>

(3.3)

where <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M82','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M82">View MathML</a>. It can be easily seen that g is increasing for <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M83','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M83">View MathML</a>, and decreasing for <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M84','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M84">View MathML</a>, <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M85','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M85">View MathML</a> as <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M86','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M86">View MathML</a>, and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M87','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M87">View MathML</a>, where <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M49','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M49">View MathML</a> and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M50','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M50">View MathML</a> are constants defined in (2.2). Therefore, there exists a constant <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M78','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M78">View MathML</a> such that <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M91','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M91">View MathML</a>, since <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M61','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M61">View MathML</a>.

Setting <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M93','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M93">View MathML</a>, we have <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M94','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M94">View MathML</a> by (3.3), which implies that <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M95','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M95">View MathML</a>, since <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M96','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M96">View MathML</a> and <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M97','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M97">View MathML</a>.

To establish (3.1), we assume that there exists a constant <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M98','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M98">View MathML</a> such that <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M99','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M99">View MathML</a>. Because of the continuity of <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M100','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M100">View MathML</a>, we can choose <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M101','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M101">View MathML</a> such that <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M102','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M102">View MathML</a>. From (3.3), we deduce that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M103','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M103">View MathML</a>

which is impossible by Lemma 1, and hence, inequality (3.1) is established.

It also follows from (2.3) that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M104','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M104">View MathML</a>

We then obtain that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M105','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M105">View MathML</a>

from which inequality (3.2) follows. □

Setting

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M106','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M106">View MathML</a>

(3.4)

we have the following lemma.

Lemma 3For all<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M107','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M107">View MathML</a>, we have the inequalities

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M108','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M108">View MathML</a>

(3.5)

Proof By Lemma 1, we have

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M109','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M109">View MathML</a>

and so

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M110','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M110">View MathML</a>

From (2.3) and (3.4), we get

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M111','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M111">View MathML</a>

It then follows from (3.1) and (3.3) that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M112','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M112">View MathML</a>

which guarantees (3.5). □

Proof of Theorem 1 Setting <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M113','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M113">View MathML</a> and differentiating it, we obtain that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M114','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M114">View MathML</a>

(3.6)

From (2.2) and (3.2), we deduce that

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M115','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M115">View MathML</a>

(3.7)

Substituting (3.7) into (3.6), we obtain

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M116','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M116">View MathML</a>

(3.8)

where <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M117','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M117">View MathML</a>.

By Hölder’s inequality, we get

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M118','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M118">View MathML</a>

(3.9)

where <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M119','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M119">View MathML</a>. Combining (3.8) and (3.9) with Lemma 3, we have

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M120','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M120">View MathML</a>

(3.10)

Integrating (3.10) over <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M121','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M121">View MathML</a>, we obtain

<a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M122','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M122">View MathML</a>

which implies that <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M123','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M123">View MathML</a> blows up at a finite time <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M124','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M124">View MathML</a>, and so does <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M13">View MathML</a>. The proof is completed. □

Remark 4 Due to the restriction of our method, we cannot get the blow-up result for <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M126','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M126">View MathML</a>, when <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M127','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M127">View MathML</a>. We conjecture that Theorem 1 will hold for all <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M128','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M128">View MathML</a>.

Competing interests

The authors declare that they have no competing interests.

Authors’ contributions

All authors contributed equally to the manuscript and read and approved the final manuscript.

Acknowledgements

This work is supported by the Natural Science Foundation of Shandong Province of China (ZR2012AM018). The authors would like to deeply thank all the reviewers for their insightful and constructive comments.

References

  1. Furter, J, Grinfield, M: Local vs. non-local interactions in populations dynamics. J. Math. Biol.. 27, 65–80 (1989). Publisher Full Text OpenURL

  2. Calsina, A, Perello, C, Saldana, J: Non-local reaction-diffusion equations modelling predator-prey coevolution. Publ. Mat.. 38, 315–325 (1994)

  3. Allegretto, W, Fragnelli, G, Nistri, P: Coexistence and optimal control problems for a degenerate predator-prey model. J. Math. Anal. Appl.. 378, 528–540 (2011). Publisher Full Text OpenURL

  4. Bebernes, J, Eberly, D: Mathematical Problems from Combustion Theory, Springer, New York (1989)

  5. Pao, CV: Nonlinear Parabolic and Elliptic Equations, Plenum, New York (1992)

  6. Wu, ZQ, Zhao, JN, Yin, JX: Nonlinear Diffusion Equations, World Scientific, Singapore (2001)

  7. Budd, CJ, Dold, JW, Stuart, AM: Blow-up in a system of partial differential equations with conserved first integral. Part II: problems with convection. SIAM J. Appl. Math.. 54(3), 610–640 (1994). Publisher Full Text OpenURL

  8. Hu, B, Yin, HM: Semi-linear parabolic equations with prescribed energy. Rend. Circ. Mat. Palermo. 44, 479–505 (1995). Publisher Full Text OpenURL

  9. El Soufi, A, Jazar, M, Monneau, R: A gamma-convergence argument for the blow-up of a non-local semilinear parabolic equation with Neumann boundary conditions. Ann. Inst. Henri Poincaré, Anal. Non Linéaire. 24(1), 17–39 (1995)

  10. Jazar, M, Kiwan, R: Blow-up of a non-local semilinear parabolic equation with Neumann boundary conditions. Ann. Inst. Henri Poincaré, Anal. Non Linéaire. 25, 215–218 (2008). Publisher Full Text OpenURL

  11. Gao, WJ, Han, YZ: Blow-up of a nonlocal semilinear parabolic equation with positive initial energy. Appl. Math. Lett.. 24(5), 784–788 (2011). Publisher Full Text OpenURL

  12. Niculescu, CP, Rovenţa, J: Large solutions for semilinear parabolic equations involving some special classes of nonlinearities. Discrete Dyn. Nat. Soc.. 2010, Article ID 491023 (2010)

  13. Liu, WJ, Wang, MX: Blow-up of the solution for a p-Laplacian equation with positive initial energy. Acta Appl. Math.. 103, 141–146 (2008). Publisher Full Text OpenURL

  14. Niculescu, CP, Rovenţa, J: Generalized convexity and the existence of finite time blow-up solutions for an evolutionary problem. Nonlinear Anal. TMA. 75, 270–277 (2012). Publisher Full Text OpenURL

  15. Zhao, JN: Existence and nonexistence of solutions for <a onClick="popup('http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M129','MathML',630,470);return false;" target="_blank" href="http://www.boundaryvalueproblems.com/content/2013/1/181/mathml/M129">View MathML</a>. J. Math. Anal. Appl.. 172, 130–146 (1993). Publisher Full Text OpenURL

  16. Li, FC, Xie, CH: Global and blow-up solutions to a p-Laplace equation with nonlocal source. Comput. Math. Appl.. 46, 1525–1533 (2003). Publisher Full Text OpenURL