Advanced Materials Research Vols. 183-185

Abstract: The aquatic ecosystem of lake is a complex open systems, taking account of the shortcomings of available eutrophication models for water quality, this study based on the principles of maximum flux selects Waihai as the object, we apply complex systems analysis to construct eutropication model which is suitable for local conditions and select a larger time scale and control parameters to simulate the eutrophication status to find out the main factors and to put forward reasonable proposals for giving out optimal control techniques. This model can be expanded in time scale, spatial scale and the number of parameters, while the difficulty of calculation and analysis will not be increased.

Abstract: The anti-fungal activities of four self-prepared rosinyl quaternary ammonium salts (QAS), QASA, BQAS1, BQAS2 and DQAS, were evaluated with paper disc method in this paper. The result showed that, all the QAS of rosin were bioactive to the selected fungi, Irpex lacteus, Trametes versicolor, Phanerochaete chrysosporium, Gloeophyllum trabeum, Chaetomium globosum, and Paecilomyces variotii. There were obvious inhibition halos for all QAS to the fungi. The result proved that the QAS of rosin were broad-spectrum anti-fungal. Especially, to white rot fungus Trametes versicolor, brown rot fungus Gloeophyllum trabeum and soft rot fungus Chaetomium globosum, they were more effective. When the concentration reached 3.2% (w/w), the inhibition halo diameters all met or exceeded 25mm. Among these four anti-fungal derivatives of rosin, the Gemini QAS (BQAS1 and BQAS2) had bigger inhibition halo diameters than the others, which indicated that the Gemini QAS of rosin were more anti-fungal than the normal QAS of rosin.

Abstract: One effective bromoamine acid (BAA) degrading strain FL was isolated previously with the ability to use BAA as the sole source of carbon and energy. The strain FL was applied in a combined process of microelectrolysis (ME) and biological aerated filter (BAF) to treat the bromoamine acid wastewater, and the treatment efficiency was investigated. It was shown that when the influent CODcr was lower than 1000 mg L-1, and the total hydrolytic retention time (HRT) was 37.7 h, the removal rate of chrominance and CODcr could reach 95.3% and 77.3% respectively. Most of the chrominance was removed by the ME treatment, while the removal of CODcr is mostly owned to the BAF treatment. After long-term contact with the BAA wastewater, the strain FL became one of the predominent species in BAF. When the system was subjected to hydraulic loading shock, the strain FL ensured the efficient removal of chrominance and BAA.

Abstract: Two columns were experimented to compare trickling filter with integrated A/O trickling filter (IA/OTT) in this study. Denitrification and phosphorus removal were limited in traditional trickling filter. By designing anoxic section, adding carbon source and recycling outflow, denitrification was enhanced in IA/OTT. Meanwhile, chemical-biological methods were used to improve the phosphorus removal. It was shown that removal efficiency of CODcr, NH3-N, TN and TP were ideal. Compared with the traditional trickling filter, especially, the removal efficiency of TN and TP were respectively about 35% and 50% higher.

Abstract: A total of 8 pure strains of ammonia-oxidizing bacteria (AOB) were collected from the rhizosphere of wetland plants including Arundo donax, Herb of rice galingale and willow. By microscopic observation and color reaction of Griess reagent, two strains of YL-1 and YS-2 were selected as the dominant genus to conduct performance investigation. Bath experiment results demonstrated that YL-1 shows the similar properties with YS-2 on the degradation of ammonia under the conditions of different pH value, ammonia loading and oxygen concentration. Both the two strains all showed excellent adaptability to the conditions of strong alkaline (pH=8.5) and high free ammonia (FA) concentration (18.2 mg/L). In spite of it, the ammonia degradation performance of the two strains to the high ammonia loading was all inhibited by the low DO condition.

Abstract: A bioflocculant-producing strain M-3 with high flocculating activity was isolated from soil by conventional panel lineation and dilution-plate methods. It was preliminarily identified as Aspergillus based on its morphological and physiological characteristics of colony. The single factor experiments were conducted to optimize cultivating factors affecting flocculating activity, the optimal culture conditions were found to be as follows: glucose 10 g/L, glutamate 2 g/L, cultivating time 36 h, cultivating temperature 37 oC, shaking speed 120 r/min, initial pH 10. The strain could produce high effective flocculants with flocculating activity of 98.3% for kaolin clay suspension, which afforded high possibility of its practical use.

Abstract: The model of second-order reaction kinetics has been used to stimulate the monochloramine decay in model and distribution system waters by nonlinear fit. Several factors were investigated, including pH, bromide, nitrite concentrations in this system. The results showed that pH value was an important factor on the monochloramine decay rate, especially when pH was below 7.0. Presence of bromide ions had different impact under experimental conditions However, when pH was above 7.60, 0.1 mg/L concentration of bromide affect hardly the decay rate of mononchloramine. The results demonstrated that the second-order kinetic model could fit well the experimental results of monochloramine decay reaction under the conditions of bromide, and nitrite ion. Finally, the work presented here validates and extends this model for use in distribution systems under realistic chloramination conditions.

Abstract: A newly isolated strain LS02 was estimated for its ability in dye decolorization. The LS02 strain was identified as Bacillus subtilis by the combination of physicochemical tests and 16S rDNA sequence analysis. The isolated strain could oxidize the laccase substrate syringaldazine, indicating the existence of laccase activity. B. subtilis LS02 grown well in the pH range of 5.0~9.0, and showed an optimum growth temperature at 37°C. Indigo carmine could be completely decolorized by B. subtilis LS02 after 4 days, whereas Remazol Brilliant Blue R, reactive black 5 and crystal violet were poorly decolorized. The result indicated that the laccase of B. subtilis LS02 may be suitable for the application in textile bleaching of indigo carmine.

Abstract: Phragmites australis are the typical vegetation in Zha Long National Natural Reserve. From August 10 to August 21st in 2006, we chose 60 quadrats in 15 sample sites, investigated the reed biomass, height, diameter, water nitrogen and phosphorus concentration. The results are as follow: 1) the average biomass of Phragmites australis models is 2858g•m-2 and the biomass between 15 sample sites is from 2029.0 to 4067.4 g•m-2; 2) the moisture content of Phragmites australis is from 42.95% to 64.95%. The average height of Phragmites australis is 272.47cm, and the average diameter of Phragmites australis is 0.51cm; 3) the NP weight ratio in each sample site concentrate from 9.18 to 15.79. Nitrogen is the most important limiting factor in Phragmites australis vegetation growing while phosphorus is not the limiting factor; 4) the Phragmites australis biomass is restricted by many factors especially water depth and water nitrogen concentration. But the phosphorus concentration in water has irrelativeness with Phragmites australis biomass.

Abstract: In order to investigate the effect of MLSS on the denitrifying dephosphorization process, a lab experiment was carried out by using an anaerobic/anoxic sequencing batch reactor (A2SBR) for a long time. The results showed that when MLSS was maintained at 2500-3500mg/L, removal efficiency of PO43--P was kept high value and it was higher than 90%.