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To realize the simultaneous removal and recovery of phosphate and partial nitrogen from stale human urine, a series of lab-scale jar tests, adopting MgCl2 x 6H2O as precipitant, were conducted to study the influence of the molar ratio of Mg/PO4(3-)-P, pH, mixing speed, reaction time and precipitation time on MAP precipitation. The experiment results showed that the molar ratio of Mg/PO4(3-)-P was found to be a very important operating parameter to affect phosphorus recovery efficiency. When the molar ratio of Mg/PO4(3-)-P was above 1.3:1, the phosphorus recovery efficiency was above 95% and the residual phosphorous was less than 10 mg/L in the solution. Increasing pH with 10 mol/L NaOH solution could not increase the recovery phosphorus efficiency obviously. Without pH control, the optimal parameters of reaction time, precipitation time and mixing speed could be set at 20 min, 2.0 h and 120 r/min, respectively. To reveal the chemical characteristics of MAP products from human urine, three MAP product samples, with no pH adjustment and under the above optimal operation condition, were obtained at different Mg/PO4(3-)-P molar ratios of 1:1, 1.3:1 and 1.5:1, respectively, and analyzed with SEM, XRD and ICP instrumentation. These precipitates were identified as nearly pure struvite (12.62% of P, 5.71% of N and 9.91% of Mg) with the presence of trace calcium, potassium and sodium. The contents of phosphorus, nitrogen and magnesium in the precipitates were 13.54%, 5.34% and 9.01% (Mg/PO4(3-)-P = 1:1), 13.78%, 5.23% and 9.36% (Mg/PO4(3-)-P = 1.3:1), as well as 13.34%, 5.12% and 9.15% (Mg/PO4(3-)-P = 1.5:1), respectively.

The objective of this study was to investigate the removal and transformation of dissolved organic matter (DOM) through laboratory-scale soil aquifer treatment (SAT) soil columns. Using XAD resins, DOM was fractionated into 3 fractions: hydrophobic acid (HPO-A), transphilic acid (TPI-A) and hydrophilic fraction (HPI). Laboratory-scale SAT columns reduced about 58.64%, 41.86% and 68.51% of HPO-A, TPI-A and HPI, respectively. All samples studied exhibited a common general relationship with respect trihalomethane formation potential (THMFP): HPO-AHPITPI-A. Specific ultraviolet light absorbance (SUVA) and specific trihalomethane formation potential (STHMFP) values for various DOM fractions increased across the SAT columns. HPI exhibited greater increase in SUVA and STHMFP than HPO-A and TPI-A. The STHMFP of HPO-A was greater than that of corresponding TPI-A and HPI fractions in all samples.

Artificial groundwater recharge is one of the efficient approaches in mitigating water shortage in China. With laboratory scale soil column system, this paper examined the migration and removal of organic matters in reclaimed wastewater during groundwater recharge. The results showed that after the secondary effluent pretreated by activated carbon was percolated through soil column system, the TOC, UV-254 and BOD5 in the effluent were removed by 44%, 34.36% and 95%, respectively, and the majority of the organic matters was removed in the first 0-0.5 m of soil column. When the TOC concentration of influent was 9-11 mg x L(-1), the variation of TOC concentration with soil depth during recharge followed exponential equation C = 10e (-0.6934h) (R2 = 0.8697). This equation could be used to well predict the TOC concentration of the effluent from soil column system.

Non-filamentous sludge bulking occurred during sludge acclimation in lab-scale bio-reactors and the characteristics, properties and degrading pollutants capability of non-filamentous sludge were analyzed. Both low DO concentration (0 - 0.7 mg/L) and low ratio of P/BOD5 (0.78/100) resulted in excessive proliferation of viscous zoogloea and sludge bulking. SVI was directly proportional to extracellular polysaccharides and was inversely proportional to hydrophobicity of sludge. The sludge bulking could be effectively controlled by increasing DO concentration and P/BOD5 ratio. Besides, adding some porous padding into viscous bulking sludge was a useful method which might avoid the deterioration of sludge settlement and maintain good performance in the system. The viscous bulking sludge could not be controlled by addition of NaC1O.

Effect of different water (tertiary effluent, secondary effluent, raw sewage as well as tap water as control) used for irrigation on the qualities of crops (cucumber, cabbage and corn) and soil was investigated; meanwhile, the contents of residual chlorine ion, phosphate, nitrate and nitrite as well as residual heavy metals present in crops were studied respectively. The results demonstrated that the secondary effluent and tertiary effluent had no significant effect on the crop quality. In contrast, irrigation with raw sewage could lead to increase of partial nutrient components in the crops. If protein contents were taken as an example, the proteins for three crops corresponding to different water sources were in the range of 0.736 2 - 0.812 5 mg/kg for cucumber, 0.134 8 - 0.164 5 mg/kg for cabbage and 10.28 - 10.84 mg/kg for corn, respectively. Irrigation with sewage produced more accumulation of nitrates (554.4 mg/kg for cabbage). Considerable effects of irrigation with secondary effluent and tertiary effluent were not observed; however, sewage was not suitable for irrigation due to an apparent accumulation of heavy metals in crops. During short-period irrigation, sodium adsorption ratio (SAR) values of soil ranged from 3.5 to 4.5, suggesting that there was no concern on soil basification. As well, obvious accumulation of heavy metals in soils was not detectable.

In air-cathode microbial fuel cell (ACMFC), oxygen diffused into the reactor from cathode without PEM can be reduced as electron acceptor via aerobic respiration by facultative microorganisms, resulting in either a decreasing of power generation or electron loss. In this study, ACMFC1 and ACMFC2 with different electrode configuration were compared to examine power density and electron recovery from glucose. The results showed that ACMFC1 generated a maximum power density of 3 070mW/m3 with internal resistance of 302.141 and anode potential of -323mV; while maximum power density of 9 800mW/m3 for ACMFC2 was obtained with internal resistance of 107.79omega and anode potential of -442mV. ACMFC2 could sustain generating electricity for nearly 220 h (ERE of 30.1%), comparing with ACMFC1 of less than 50 h (ERE of 9.78%) under batch operation. Therefore, an improved design for electrode configuration of ACMFC can be performed to generate higher power with low internal resistance, meanwhile, achieve increasing electron recovery simultaneously.

An air-cathode microbial fuel cell (ACMFC) was successfully started up using anaerobic activated sludge as inoculums, generating a voltage of 0.24V after inoculations for 110 h. When using acetate and glucose as substrate, voltage of 0.38V and 0.41V (based on external resistance of 1000 omega) is obtained; meanwhile, the maximum power density reaches 146.56 mW/m2 and 192.04 mW/m2 respectively, suggesting that organic wastewater can be used to produce electricity. Removal efficiency of 99% (acetate) and 87% (glucose) is achieved simultaneously, demonstrating that ACMFC can treat organic wastewater. Electron recovery efficiency as low as 10% for both acetate and glucose is observed mainly due to aerobic respiration of microorganisms caused by diffusion of oxygen molecular from the cathode, leading to electron loss. MFCs are capable of converting chemical energy presented in organic wastewater into electricity energy with accomplishments of wastewater treatments simultaneously, which possibly captures considerable benefits in terms of environments and economics.

Landfill leachate recirculation treatment process is a promising and economic way in northeast China due to the distinct season variation. In order to study the impact of recirculation on leachate production and its quality, two simulated sanitary landfill reactors, one with leachate recirculation and the other without, were placed outdoor in Harbin. The two-year experimental results indicated that leachate production was reduced by 86% with leachate recirculation and less or no facility for leachate treatment required. Recirculation could improve the leachate quality dramatically with lower COD, SS, NH4(+)-N and higher pH level. Recirculation also could enhance waste degradation and stabilization and improve the efficiency of landfill. This study confirmed that leachate recirculation was a very feasible way for on-site landfill leachate treatment in cold areas.

The analytical hierarchy process (AHP) was adopted to study the index system of eco-province and the index system was set up for eco-province construction. The comparison matrix was constructed on the basis of experts' investigation questionnaires. MATLAB 6.5 was used to confirm the weights of the indices. The general environment quality index model was used to grade the environment quality and assessed the progress of constructing eco-province in Heilongjiang province. The results indicate that it is feasible to apply the AHP to assess quantitatively the ecological environmental quality province-wide. The ecological environment quality of Heilongjiang province has been improved obviously from the beginning of eco-province construction.

Leachate production is evidently discontinuous in the chilly northeast areas because of the distinct 4-seasons conversion and long frozen time. In order to investigate into the leachate production variability and the impact of leachate recirculation on sanitary landfill, two simulated landfill reactors were constructed outdoors, which were filled with the same municipal solid waste. One reactor was provided with leachate recirculation and the other without as a control. On the basis of the obtained leachate production data and evaluation of the available leachate predictive models, the empirical model was recommended and the parameters within the formula were determined through linear regression analysis, which was proved to be reliable and practical. The results provided a scientific basis for the prediction of leachate production, design of leachate collection and treatment system. Besides, this study indicated that leachate recirculation was feasible for leachate treatment in the cold areas.

It has been showed that triptolide (T10) has antitumor activities. This study was to observe the inhibitory effects of T10 on proliferation of vascular endothelial cells and expression of urokinase-type plasminogen activator (u-PA), and to elucidate the antiangiogenic mechanism of T10.Human umbilical vein endothelial cells were cultured in vitro for 3 generations, and treated with T10 (0, 5, 10, 20, and 30 microg/L), or dexamethasone (300 mg/L) as control. Cell count and 3H-TDR incorporation were used to observe cell proliferation. The chick embryo chorioallantoic membrane (CAM) test was carried out to observe the effect of T10 on angiogenesis. Immunohistochemistry and real-time quantitive reverse transcription-polymerase chain reaction (RT-PCR) were used to detect protein and mRNA levels of u-PA.T10 inhibited the proliferation of umbilical vein endothelial cells in a dose-dependent manner; inhibitory rate of endothelial cells was 28.93% after treatment of 5 microg/L of T10. T10 significantly reduced angiogenesis in CAM, even at the concentration of 5 microg/L (P0.05). T10 decreased protein and mRNA levels of u-PA in endothelial cells in a dose-dependent manner; the protein level of u-PA was reduced by 41.05% after treatment of 5 microg/L of T10.T10 could inhibit the proliferation of human umbilical vein endothelial cells and expression of u-PA, which may contribute to its antiangiogenic activity.

To investigate the inhibitory effects of triptolide on the migration, gene and protein expression of urokinase-type plasminogen activator (u-PA) of endothelial cells (ECs) cultured in vitro and to elucidate the anti-angiogenic mechanism of triptolide.Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and the passage 3 cells were treated with triptolide (0, 5, 10, 20, 30 microg/L). Three-dimensional culture system was used to assess the effect of triptolide on the migration of HUVECs. Real time quantitive reverse transcription polymerase chain reaction and immunohistochemical assay were applied to detect gene and protein expression of u-PA.Triptolide decreased the migration activity and suppressed the expression of u-PA of HUVECs at the gene and protein level.Triptolide could inhibit the migration of ECs by reducing the gene and protein expression of u-PA. These may contribute to an elucidation of the mechanism by which triptolide inhibits the angiogenesis.

A strain from Bacillus thuringiensis var. israelensis de Barjac (B. t. i), having a fatal toxicity to chironomids, was immobilized in the PVA-H3BO3 gel beads confected with a bit of sodium alginate and activated carbon. The result showed that optimal weight ratios were 10% PVA, 1% sodium alginate and 20% activated carbon, respectively. When 4% calcium chloride saturated boric acid solution (pH=6.7) was used as gelatin agent for gelating 24 h, the produced gel beads had good performance in mechanical strength. This method is proved to be simple and cheap. The toxicity of the beads to chironomids is high and the release is slow.

In order to remove the low turbidity present in surface water, a novel metal-polysilicate coagulant was used to treat the raw water taken from Tanjiang River in Guangdong Province. This study on the effects of Al/Fe molar ratio on the performance of a complex compound formed by polysilicic acid, aluminium and ferric salt (PAFS) showed that PAFS with Al/Fe ratio of 10:3 seemed to have the best coagulation performance in removing turbidity and color. Experimental results showed that under the conditions of polymerization time of 15 d, sedimentation time of 12 min, and pH of 6-8, PAFS with Al/Fe molar ratio of 10:3 had the best coagulation efficiency and lowest residual Al concentration. The turbidity decreased from 23.8 NTU to 3.23 NTU and the residual Al concentration was only 0.165 mg/L in the product water. It could be speculated that colloidal impurities and particulate Al were removed by adsorption bridging and electrical neutralization of long chain inorganic polymer coagulants.

With the growing concern regarding emission of volatile organic compounds (VOCs) from wastewater treatment plants (WWTPs), the relationship between the VOC emission rates and the associated public health risks has been rarely discussed. The objective of this study was to examine and compare the VOC emission rates and cancer and non-cancer risks by inhalation intake, using a municipal WWTP in China as an example, with respect to the effects of treatment technologies, VOC species, and seasonal variation. Given the treatment technology considered, the emission rates of VOCs in this study were estimated by means of mass balance or calculated on the molecular level. From the viewpoints of both emission rates and cancer and non-cancer risks, sedimentation was the treatment technology with the highest health risks to the workers. Slightly lower VOC emission rates and health risks than those for sedimentation were observed in anaerobic treatment. Although the aeration significantly enhanced the VOC emission rates in the aerobic treatment process, the associated health risks were limited due to the low VOC concentrations in the gas phase, which were likely attributed to the strong mixing and dilution with fresh air by aeration. Amongst the VOCs investigated, benzene was the VOC with both a relatively high emission rate and health risk, while trichloroethylene possessed a high emission rate but the lowest health risk. Without strong interfacial aeration and turbulence between the water and atmosphere, the effects of treatment technology and seasonal variation on the health risks might be connected to the VOC emission rates, while the effect of VOC species depended considerably on the respective cancer slope factors and reference concentrations; the employment of aeration provided a different conclusion in which the emission rates were enhanced without a significant increase in the related cancer risks. These findings can provide insight into future health risk management and reduction strategies for workers in WWTPs.