Using the Ramsey-Cass-Koopmans model with heterogeneous agents, this note presents the explicit relationship between the individual's asset holding and the aggregate capital stock. With the aid of this relationship, is examined the dynamics of income distribution as the economy expands. Finally, some examples are presented, contrary to the conjecture made in Li, Xie, and Zou (2000), showing that the income can still improve over time, even when the aggregate production function is convex.
Objective To compare the biodegradation of di-n-methyl pathalate by free and immobilized microbial cells. Methods The enrichment and isolation technique was used to isolate the microorganism. The PAV-entrapment method was utilized to immobilize the microorganisms. The scanning electron microscophy (SEM) was used to observe the growth and distribution of microbial cells immobilized inside the PVA bead gels. The GC/MS method was used to identify the main intermediates of DMP degradation. Results The microbial cells could grow quite well in PVA gel. The metabolic pathway did not change before and after immobilization of the microbial cells. The degradation rate of immobilized cells was higher than that of free cells. Conclusion The immobilized microbial cells possess advantages than free cells when applied to the biodegradation of toxic organic pollutants.