摘要：The unified dynamic theory reveals the substrate-based nonlinear growth phenomena. It means that the environment of high organism concentration and low substrate state is useful for the growth of weak floras. With ecological superior nitrification denltrification （ ECOSUNIDE ） technology, high sludge concentration by distributing influent to anaerobic and anoxic zones is carried out, and the ecological superiorities of nitrifiers, denitrifiers, and phosphate accumulating organisms （PAOs） get to be promoted. One of the anaerobic/anoxic/oxic（A/A/O） treatment lines of a sewage treatment plant with ECOSUNIDE technology for further investigation on the nutrient removal efficiency is reformed. The advantages of ECOSUNIDE, such as high efficiency and saving energy, are well demonstrated, even under the condition of low temperature （about 15℃） and carbon-resource （C/N ratio lower than 2. 5 ）. In ECOSUNIDE system, the effluent indexes as biochemical oxygen demand （BOD）, chemical oxygen demand （COD）, and NH3--N reach the Class I-A criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant （ GB18918-2002 ）, and suspended substance （ SS ）, total nitrogen （TN）, and total phosphorus（TP） meet the Class I -B criteria. While the effluent qualities of A/A/O system only reach the secondary discharge standard. Through the comparison on the sludge character of ECOSUNH）E system with A/A/O, more abundant biofacies, darker and more intense zoogloea, more obvious filamentous bacterium, and clearer floes edges in ECOSUNIDE system are found.

摘要：Novel applications of nanotechnology may lead to the release of engineered nanoparticles（ENPs）, which result in concerns over their potential environmental hazardous impact. It is essential for the research workers to be able to quantitatively characterise ENPs in the environment and subsequently to assist the risk assessment of the ENPs. This study hence explored the application of nanoparticle tracking system（NTA） to quantitatively describe the behaviour of the ENPs in natural sediment-water systems. The NTA allows the measurement of both particle number concentration（PNC） and particle size distribution（PSD） of the ENPs. The developed NTA method was applied to a range of gold and magnetite ENPs with a selection of surface properties. The results showed that the positively-charged ENPs interacted more strongly with the sediment than neutral and negatively-charged ENPs. It was also found that the citrate coated Au ENPs had a higher distribution percentage（53%） than 11-mercaptoundecanoic acid coated Au ENPs（20%） and citrate coated magnetite ENPs（21%）. The principles of the electrostatic interactions between hard（and soft） acids and bases（HSAB） are used to explain such behaviours; the hard base coating（i.e. citrate ions） will interact more strongly with hard acid（i.e. magnetite） than soft acid（i.e. gold）.The results indicate that NTA is a complementary method to existing approaches to characterise the fate and behaviour of ENPs in natural sediment.