Construction of double tube granular sludge microbial fuel cell and its characteristics and mechanism of azo dye degradation.

Microbial fuel cells (MFCs) can obtain electrical energy from extensive organic matter and complete wastewater treatment at the same time. The principal purpose of the research is to find a solution to the biodegradation of X-3B in a double tube MFC with graphite fiber brush as the anode and carbon cloth as the cathode. The anaerobic, aerobic, and electrochemical processes in the MFC were investigated. The effects of dye concentration and circuit connectivity on the performances of MFCs were explored. The degradation efficiency of X-3B in the anode region (85.56%) was higher than that in the cathode region (14.16%) within 24 h under the optimal voltage of 0.43 V, indicating a synergistic effect between electrode reaction and biodegradation. The power density increased from 12.12 mW/m3 to 60.45 mW/m3 with the addition of X-3B from 50 to 200 mg/L, because of the reduced ohmic and polarization resistance. Intermediate productions such as aniline were manufactured with the conjugated double bond of X-3B broken, and the intermediates were degraded into small molecular products like phenol during further degradation processes. Moreover, dye concentration and circuit connection had significant effects on the relative abundance of the microbial community at phylum and genus levels. In general, MFC is a good approach to energy generation and azo dye treatment at the same time.

The mitigating effects of enhanced reinforcer magnitude and quality on treatment degradation.

Differential reinforcement of alternative behavior is a common intervention for problem behavior in persons with neurodevelopmental disorders, but it is susceptible to integrity errors that can degrade treatment effects. Manipulating reinforcement parameters to favor alternative behavior might make it more persistent in the face of integrity errors. We devised an analog of differential reinforcement of alternative behavior to examine if enhanced reinforcer magnitude or quality for the alternative response could protect against treatment degradation. Across 2 experiments, reinforcer magnitude or quality was manipulated to favor the alternative response in 1 condition but kept constant across both alternative and target responses in a second condition. Comparisons of the 2 conditions indicated that higher-magnitude or higher-quality reinforcement for alternative behavior can mitigate against treatment degradation when treatment errors occur and provided support for the utility of considering parameters of reinforcement when developing behavioral interventions for problem behavior.