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介绍了美国《清洁水法》中的公众参与要求,以及美国国家污染物排放削减(NPDES)许可证制度,并对NPDES许可证的发放进行了详细说明。同时,用诸多实例介绍了NPDES许可证制度实施过程中因涉及避开公众监督而导致的法律挑战,论述了缺少公众意见可能带来的问题。文章指出,让公众获得更多信息并参与环保决策,可推动决策的执行,强化问责机制,保障公众的利益,并对改善水质尤为重要。 相似文献
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A new treatment technology of municipal solid waste incineration (MSWI) fly ash is presented in this paper. Feasibility of solidification/stabilization treatment of MSWI by successively adding trimercapto-s-triazine and cement, and the effect of addition, fly ash size and curing time were studied by batch tests. The results showed that MSWI posed a huge environmental risk, the partial distribution showed normal distribution approximately. Treatment of fly ash with trimercapto-s-triazine and cement showed a good effect, the leaching toxicity of treated fly ash solidified blocks with 2% trimercapto-s-triazine and 20% cement could meet the standard for pollution control on the landfill site of MSW in China after curing for 7 days, and the flexural strength of solidified blocks could reach 2.4 MPa. Ground fly ash had a positive effect on both leaching toxicity and strength. 相似文献
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The objective of this study was to investigate if coexisting compounds could affect the fate of pharmaceuticals in surface water under solar irradiation. The degradation of metronidazole (MET) in the presence of different coexisting pharmaceuticals was investigated in batch experiments with exposure to sunlight. Tinidazole, which has a similar structure to MET, was employed as an analogue. The results indicated that the presence of an analogue with a similar photosensitive group to MET could inhibit the photodegradation of MET. In addition, the effect of coexisting pharmaceuticals with different absorption spectra on the degradation of MET was investigated. The results showed that the effect depended on the degree of overlapping absorption spectra between MET and the coexisting pharmaceuticals. The relationship between the degree of the influence and the ultraviolet absorption spectra of coexisting pharmaceuticals found in this study could give guidance in assessing the fate of pharmaceuticals in environmental water. 相似文献
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In order to extract intracellular lipids from cyanobacterial Synechocystis PCC 6803 for biofuel production, seven cell-disruption methods - autoclaving, bead beating, freeze drying, French press, microwave, pulsed electric fields (PEF), and ultrasound - were tested prior to lipid extraction to make intracellular lipids more accessible by organic solvents. The different methods brought about distinct disruption effects to the cell envelope, plasma membrane, and thylakoid membranes that were related to extraction efficiency. Microwave, PEF, and ultrasound with temperature control had significant enhancement of lipid extraction (9-13% increases). Bead beating, freeze drying, and French press did not provide significant enhancement of lipid extraction. Furthermore, autoclaving, French press, and ultrasound treatments caused significant release of lipid into the medium, which may increase solvent usage and make medium recycling difficult. In order to minimize the cost of cell-disruption and lipid-extraction steps, microwave and PEF (with temperature control) might be best suited for large-scale cell disruption among all techniques investigated. 相似文献
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TRANSIENT FLOWS AND PRESSURE WAVES IN PIPES 总被引:1,自引:0,他引:1
Wang Xiu-qing 《水动力学研究与进展(B辑)》1995,(2)
TRANSIENTFLOWSANDPRESSUREWAVESINPIPESWangXiu-qing(NuclearIndustryManagementInstitute,PostOfficeBox1267,Beijing102600,P.R.Chin... 相似文献
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万安水电站位于赣江中游,肩负有上下游防洪任务,下游防洪控制点为吉安、石上两站.电站正常运行后,正常蓄水位和防洪高水位均为100.00m,防洪限制水位和死水位均为90.00m.受移民条件限制,初期运行上述特征水位均降低,主汛期4~6月库水位控制在85.00m,发电水头比正常运行降低5m,机组出力受阻达40%以上,致使电站效益不能充分发挥,而4~6月恰为用电高峰期,电网缺电十分严重.为解决主汛期发电和防洪的矛盾,提出了汛期采用预泄办法提高运行水位的方法,即在水文气象预报的有效预见期(18~24h)内,按8800m3/s控制下泄,使库水位从8800m或90.00m泄至85.00m,可满足万安水电站防洪的两个约束条件,即回水对赣州市的影响既不超过0.3m,也不会加重下游的防洪负担.经过1993年6月的实际运行,证明此方法是可行和有效的,提高万安水电站的运行水位,既增加了经济效益,又提高了运行水头,改善了机组工况. 相似文献