Batch experiments were carried out for 7 days to investigate the simultaneous removal of various organic and inorganic contaminants including total nitrogen (TN), total phosphorus (TP), metals, pharmaceuticals and personal care products (PPCPs), endocrine disrupting chemicals (EDCs), and estrogenic activity in wastewater by four freshwater green microalgae species, Chlamydomonas reinhardtii, Scenedesmus obliquus, Chlorella pyrenoidosa and Chlorella vulgaris. After treatment for 7 days, 76.7-92.3% of TN, and 67.5-82.2% of TP were removed by these four algae species. The removal of metals from wastewater by the four algae species varied among the metal species. These four algae species could remove most of the metals efficiently (>40% removal), but showed low efficiencies in removing Pb, Ni and Co. The four algae species were also found to be efficient in removing most of the selected organic compounds with >50% removal, and the estrogenic activity with removal efficiencies ranging from 46.2 to 81.1% from the wastewater. Therefore, algae could be harnessed to simultaneously remove various contaminants in wastewater. Environmental impactDomestic wastewater contains various inorganic and organic contaminants, which could pose risks to the environment and public health. To avoid these adverse effects, wastewater must be treated prior to its nal discharge into the receiving environment. Unfortunately, incomplete removals have oen been reported for these contaminants in wastewater by conventional wastewater treatment technologies. The use of microalgae in the treatment of wastewater has gained great interest over the past few years. However, previous studies on wastewater treatment by algae have been limited and most of them are focused on the removal of inorganic or organic pollutants in articial wastewaters. This study investigated the simultaneous removal capacity of inorganic (nitrogen, phosphorus and metals) and organic pollutants (PPCPs and EDCs) by four freshwater microalgae, and also evaluated the elimination of estrogenic activity in the wastewater by these algae species. The results demonstrated that simultaneous removal of various contaminants in wastewater was achieved, which showed potential application of these algae species in the wastewater treatment.

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Serious phytoplankton blooms occurred repeatedly every spring in many bays of the Three-Gorges Reservoir. However, little was known about the impact of phytoplanktivorous fish on spring phytoplankton community structure in the Three-Gorges Reservoir. In this study, an enclosure experiment was conducted to assess the impact of silver carp (Hypophthalmichthys molitrix) on the plankton community structure and water quality of the Three-Gorges Reservoir during 2 April to 2 May 2008. The field experiment was performed in six enclosures. Stocking silver carp into enclosures caused a dramatic change in the aquatic ecosystem. For example, pH, transparency, DO and phosphate were reduced, while chlorophyll-a concentration and turbidity increased dramatically. Furthermore, during the enclosure experiment, some zooplankton such as rotifer and copepoda were significantly reduced, and some phytoplankton and protozoa were significantly increased by silver carp. The predation by silver carp might have increased phytoplankton biomass through reducing the densities of some zooplankton which directly fed on phytoplankton. It was concluded that silver carp was not suitable for clearing spring phytoplankton (<20 μm) blooms in the Three-Gorges Reservoir at the present time

The effect of primary air fraction f 1 , outer secondary air swirl strength and excess oxygen coefficient on the combustion characteristics of petroleum coke, Hejin lean coal and Shenmu soft coal are researched on a onedimensional furnace using a dual channel swirl burner. The results show that with the increase in primary air fraction f 1 , the NO x emission concentrations of both Hejin lean coal and petroleum coke increase, and the combustion worsens in the earlier stage, but the burn-out rate of Shenmu soft coal is improved. The NO x emission concentration obtains a minimum value with an increase in f 1 . The ignition and burn-out rate of petroleum coke and Shenmu soft coal are optimal when Ω dl is minimum and Ω dl = 0.87, respectively. However, both the NO x emission concentration of petroleum coke and Shenmu soft coal are minimum when Ω dl = 1.08. The increase in excess oxygen coefficient delays the ignition of petroleum coke, worsens the combustion condition and increases the NO x emission concentration, but it greatly decreases the NO x emission concentration of Shenmu soft coal.

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