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Novel magnetic-activated carbon composites (MACs) were synthesized via coupling of a glucose-assisted hydrothermal pretreatment and subsequent thermal treatment using iron sludge and biological sludge. The adsorption properties of MACs for sulfonamide antibiotic removal from aqueous solution were investigated. Results revealed that the MACs had a high specific surface area with well-distributed magnetic nano-sized Fe3O4/Fe0 particles with a graphitic shell. This finding indicates that the ferric compounds in the iron sludge were not only converted into magnetic ferrite but also worked as activators for graphitization of the surrounding amorphous carbon. The pseudo-second-order kinetics and Langmuir models were shown to well fit sulfonamide antibiotic adsorption on the MACs. There was a high correlation between the kl·qm and physicochemical parameters of the sulfonamides. The three parameters are molecular polarizability, octanol-water partition coefficient, and solubility, respectively. The sulfonamide adsorption by the MACs was highly pH dependent. Hydrophobic interaction, π-π interaction, as well as electrostatic interaction, played dominant roles in the sulfonamide adsorption.

Fish nocardiosis is a chronic granulomatous bacterial disease and three pathogens have been reported so far, including Nocardia asteroids, N. seriolae and N. salmonicida. However, the absence of antigen markers is a bottleneck for developing effective vaccines against fish nocardiosis. In this study, the antigenicity of whole-cell protein of these three pathogenic Nocardia species were profiled by immunoproteomic analysis and 7 common immunogenic proteins were identified as follows: molecular chaperone DnaK (DnaK), molecular chaperone GroEL (GroEL), 30 S ribosomal protein S1 (RpsA), TerD family protein (TerD), FHA domain-containing protein (FHA), 50 S ribosomal protein L7/L12 (RplL) and PspA/IM30 family protein (PspA). Furthermore, the DNA vaccine encoding FHA gene against fish nocardiosis was developed and its efficacy was investigated in hybrid snakehead. The results suggested that it needed at least 7 d to transport pcDNA-FHA DNA vaccine from injected muscle to head kidney, spleen and liver and stimulate host's immune system for later protection. In addition, non-specific immunity paraments (serum lysozyme (LYZ), peroxidase (POD), acid phosphatase (ACP), alkaline phosphatase (AKP) and superoxide dismutase (SOD) activities), specific antibody (IgM) titers production and immune-related genes (MHCIα, MHCIIα, CD4, CD8α, IL-1β and TNFα) were used to evaluate the immune response induced in pcDNA-FHA vaccinated hybrid snakehead, it proved that all these mentioned immune activities were significantly enhanced after immunization. The results also showed hybrid snakehead vaccinated with pcDNA-FHA had higher survival rate (79.33%) compared with the controls after challenge with N. seriolae, indicating that the pcDNA-FHA DNA vaccine can supply immune protection against N. seriolae infection. Taken together, this study may warrant further development of these common immunogenic proteins as the antigens for vaccine or diagnosis and facilitate the prevention and treatment of fish nocardiosis.

The effects of Limnodrilus hoffmeisteri bioturbation on nitrogen releasing from sediments of the East Lake Dongting,with the different densities and environments were studied in this paper.The results showed that bioturbation of L.hoffmeisteri had a good accelerating effect on nitrogen release from sediments,which was caused mainly by ammonium release.When the density of L.hoffmeisteri was at 1 and 2ind./cm2,the concentrations of total nitrogen in overlying water were increased by 15% and 32% respectively comparing to the control test.Appropriate increasing of temperature was helpful for vital movement of L.hoffmeisteri,which caused that total nitrogen release increment were increased by 23% and 69% respectively when temperatures were 15℃ and 25℃ compared to the cotrolling 5℃.Adversity stress on L.hoffmeisteri,induced by acidic and alkali environments,enhanced its bioturbation effect and also accelerated nitrogen releasing.In comparison with a condition of pH 7,total nitrogen release increment were increased by 32% and 41% when pH values were 5 and 9,respectively.Total nitrogen release increment in hypoxia was 1.52 fold compared to the aerobic environment,which indicated that L.hoffmeisteri had good adaptability and survivability to hypoxia environment in which bioturbation was stronger than in aerobic environment.

This study investigated the release rule of total nitrogen from sediments by Tubifex tubifex bioturbation indifferent environmental conditions. Tubifex tubifex densityi¢temperaturei¢pH value and dissolved oxygen were selected as influencing factors. The results showed that bioturbation of Tubifex tubifex had a good accelerating effect on total nitrogen release of sediment and the concentration of total nitrogen in overlying water respectively increased to 1.2 fold and 1.3 fold when Tubifex tubifex density was 1ind./cm2 and 2ind./cm2compared to control test. Appropriate increasing of water temperature was helpful to the fast growth of Tubifex tubifex, which caused that total nitrogen in overlying water raised by56 percent when temperature increased from 15iae to 25iae. Adversity stress on Tubifex tubifex, induced by acidic and alkali environment, enhanced its bioturbation effect and also accelerated the total nitrogen releasing from sediment. Total nitrogen increase amplitude of overlying water in anaerobic was 1.3 fold compared to aerobic environment, which indicated that Tubifex tubifex had good adaptability to anaerobic environment in which bioturbation was more than in aerobic environment.

the ammonia nitrogen and phosphorus adsorption on natural zeolite were studied. Experimental data shows, the Freundlich and Langmuir models agrees very well with experimental data on ammonium and phosphorus, respectively, Zeolite adsorption of ammonia nitrogen and phosphorus removal process should follow the secondary dynamic equation, In certain concentration range of ammonia nitrogen, zeolite and phosphorus removal rate increased with the initial concentration, With the increasing of zeolite dosage and mesh of zeolite, the absorption efficacy on ammonia nitrogen and phosphorus is better, pH6-10, adsorption effect of ammonia nitrogen on natural zeolite is good, are more than 70%, pH

O3-biological zeolite processes was used to treat micro-polluted raw water, The results show that zeolite modified by NaCl is efficiency on ammonia-nitrogen removal, at pH 6~9 and 150min stirring time, the ammonia-nitrogen removal rate is 71.2%;During the culture of biofilm, ammonia-nitrogen removal rate of water treated by biological zeolite increased after decreasing. When the biofilm is mature, the removal rate will stay at a high level during a long time, the average removal rate is 78%, The ammonia-nitrogen removal rate of water treated by O3-biological zeolite is 90%, after micro-organisms domestication completed, which is higher than that of water treated by modified zeolite or biological zeolite.