考察一类具有抑制剂的质体负载(plasmid-bearing)与质体自由(plasmid-free)的物种相互竞争的恒化器模型.首先,研究了全局分支的形状和正平衡态的多解性.结果表明,存在μ^*〉0,使得如果体现抑制剂作用的参数μ〉μ^*,则分支为次临界的,且当u的最大生长率a满足一定条件时,模型至少存在两个共存解.其次,得到了模型的一些动力学行为.采用的主要数学工具包括分歧理论,锥映射上的度理论,各种比较原理和椭圆估计.
This paper deals with a chemostat model with an inhibitor in the context of competition between plasmid-bearing and plasmid-free organisms. First, the shape of global bifurcation branch and existence of multiple positive steady states are examined. It turns out that there exists μ^* 〉 0 such that if the parameter, which represents the effect of the inhibitor, μ 〉 μ^*, then the bifurcation is subcritical and this model has at least two coexistence solutions provided that the maximal growth rate a of u lies in a certain range. Secondly, some dynamical behavior of this model is also established. The main mathematical approach relies on bifurcation theory, degree theory in cones, various comparison principles and elliptic estimates.