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Non-autonomous single-species growth chemostat models with general response functions are considered. In the models, the dilution rate and removal rate are allowed to be different from each other. A series of new criteria on the boundedness, permanence, persistence, average persistence and extinction of the population is established. In particular, when models degenerate into the almost periodic case, the equivalences of the permanence, persistence and average persistence of species are obtained. These results improve and extend some well-known corresponding results obtained in Refs. 1, 14 and 17.

The vertical hybrid constructed wetland (VHCW) is a new constructed wetland for treating decentralized domestic sewage. A comparative study of the efficiency of contaminant removal rate between two kinds of vertical hybrid constructed wetlands was conducted on a middle-scale (4000 mm length ×2000 mm width ×2000 mm height). The results showed that the average removal rates were 55.64% for CODcr, 47.93% for TN, 50.41% for NH₃-N, 51.67% for TP in the integrative vertical hybrid constructed wetland system and the average removal rates were 75.15% for CODcr, 57.08% for TN, 60.06% for NH₃-N, and 55.08% for TP in segregated vertical hybrid constructed wetland system. There is a significant difference in CODcr removal rate between two vertical hybrid constructed wetland while the removal rates of TP nearly have no difference between two vertical hybrid constructed wetlands (VHCWs). In the first month of the experiment, the removal rates of nutrient are unstable and low. Because the concentration of influent was unstable and the temperature was relativity low, microbial activity can be influenced by temperature. Microorganisms' respiration was the major process for CODcr removal and plant uptake and substrate have an important effect on TN and TP removal. The segregated vertical hybrid constructed wetland system removal efficiency of contaminants is better than that of integrative vertical hybrid constructed wetland system and it can be used in the actual project.

Chlorophenol compounds are widely used as insecticide and herbicide, which have caused environmental pollution in many areas. In this study, degradation characteristics of o-chlorophenol with a strain of Rhodopseudomonas sp. PSB-1D were investigated under dark aerobic condition. The experiment results of relationship between PSB-1D growth and o-chlorophenol degradation showed that removal rate of o-chlorophenol was up to 71% at the end of cell growth stationary phase (about 168 h culture time). The main environmental factors including initial pH and rotation speed had distinctly influenced on o-chlorophenol removal with PSB-1D. The results showed that the optimum conditions were initial pH 7.0 and rotation speed 130 rpm. Under the optimum cultural conditions, cell growth density (OD₅₆₀) and removal rate of o-chlorophenol could reach to 1.622 and 74.2%, respectively. In addition, the degradation kinetic data fits the Andrews model well, and the biodegradation process of o-chlorophenol under dark aerobic condition can be well described by enzymatic reaction of high concentration inhibition with the maximum velocity of enzyme catalyzed reaction rate 0.209 d⁻¹, Michaelis-Menten constant 5.337 mg/L, and inhibitory constant 459.84 mg/L.