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971.
都市工业园区规划环评的实践与思考   总被引:1,自引:1,他引:0  
通过对白沙洲都市工业园规划环评筹备、撰写、执行等环节的剖析,总结了该规划环评的特点,并指出基层环保组织在推动规划环评过程中所起的作用。对应用规划环评成果为园区和谐快速发展服务提出建议。着重探讨了基层环保部门该如何推动规划环评,促进城市中心老工业区改造,发展都市工业因,乃至生态工业园,实现城区经济又好又快发展。提出了法律赋予环保部门管理规划环评的职权不足、公众参与流于形式、规划环评法律约束不力等规刘环评实践过程中遇到的主要问题,并给出建议。  相似文献   
972.
The effects of disinfection efficiency on microbial communities and the corrosion of cast iron pipes in drinking water distribution systems (DWDSs) were studied. Two annular reactors (ARs) that simulated actual running conditions with UV/Cl2 disinfection and chlorination alone were used. High chlorine consumption and corrosion rate were found in the AR with UV/Cl2. According to functional genes and pyrosequencing tests, a high percentage of iron recycling bacteria was detected within the biofilm of the AR with Cl2 at early running stage, whereas siderophore-producing bacteria were dominant in the biofilm of the AR with UV/Cl2. At the early running stage, the sequential use of UV light and an initial high chlorine dosage suppressed the biomass and iron-recycling bacteria in both bulk water and biofilms, thereby forming less protective scales against further corrosion, which enhanced chlorine consumption. Non-metric multidimensional scaling analysis showed that the bacterial communities in the ARs shaped from within rather than being imported by influents. These results indicate that the initial high disinfection efficiency within the distribution system had not contributed to the accumulation of iron-recycling bacteria at the early running stages. This study offer certain implications for controlling corrosion and water quality in DWDSs.  相似文献   
973.
974.
Nanoporous carbons(NPCs) derived from metal–organic frameworks(MOFs) are attracting increasing attention in many areas by virtue of their high specific surface area, large pore volume and unique porosity. The present work reports the preparation of an NPC with high surface area(1731 m~2/g) and pore volume(1.68 cm~3/g) by direct carbonization of MOF-5. We examined the adsorption of three typical contaminants from aqueous solutions, i.e., sulfamethoxazole(SMX),bisphenol A(BPA) and methyl orange(MO), by using the as-prepared NPC. The results demonstrated that NPC could adsorb the contaminants effectively, with adsorption capacity(qm) of 625 mg/g(SMX), 757 mg/g(BPA) and 872 mg/g(MO), respectively. These values were approximately 1.0-3.2 times higher than those obtained for single-walled carbon nanotubes(SWCNTs) and commercial powder active carbon(PAC) under the same conditions. With its high surface area and unique meso/macropore structure, the enhanced adsorption of NPC most likely originates from the cooperative interaction of a pore-filling mechanism, electrostatic interaction,and hydrogen bonding. In particular, the p H value has a crucial impact on adsorption, suggesting the significant contribution of electrostatic interaction between NPC and the contaminants. This study provides a proof-of-concept demonstration of MOF-derived nanoporous carbons as effective adsorbents of contaminants for water treatment.  相似文献   
975.
The importance of enhancing sludge dewaterability is increasing due to the considerable impact of excess sludge volume on disposal costs and on overall sludge management. This study presents an innovative approach to enhance dewaterability of anaerobic digestate(AD) harvested from a wastewater treatment plant. The combination of zero valent iron(ZVI, 0–4.0 g/g total solids(TS)) and hydrogen peroxide(HP, 0–90 mg/g TS) under pH 3.0 significantly enhanced the AD dewaterability. The largest enhancement of AD dewaterability was achieved at 18 mg HP/g TS and 2.0 g ZVI/g TS, with the capillary suction time reduced by up to 90%. Economic analysis suggested that the proposed HP and ZVI treatment has more economic benefits in comparison with the classical Fenton reaction process. The destruction of extracellular polymeric substances and cells as well as the decrease of particle size were supposed to contribute to the enhanced AD dewaterability by HP + ZVI conditioning.  相似文献   
976.
随着中国国民经济的不断发展和城乡一体化建设的发展,市政工程设施建设获得了空前发展。随着国民环保意识的增强,国家对城市污水治理及排放标准提高,政府提倡节能减排。因此,国内现有众多的污水处理厂需进行大量的提标改造,为了更好的利用原有的水处理构筑物,减少浪费,根据近些年的水处理构筑物改造与加固设计工程实践,对污水处理厂水处理构筑物的改造与加固技术进行了探索与总结,供类似的工程设计参考借鉴。  相似文献   
977.
对长江中下游 南黄海地震带地震活跃期、幕划分及其发展趋势进行了研究,对江苏及其邻区今后几年的地震大形势及重点危险区进行了判定。分析认为,长南带从1971年以来进入第二活跃期的第3幕,该幕地震活动将持续到2010年前后,最高活动水平为6.5级左右。今后几年江苏东部至南黄海海域发生5~6级或6级以上地震的可能性较大。  相似文献   
978.
GIS在震后应急反应中的应用   总被引:8,自引:2,他引:6  
震后应急反应是减轻震害的关键措施之一。震后应急的基础在于信息的收集和处理。GIS(地理信息系统)具有很强的信息管理能力和空间数据处理、分析能力。借助于这个系统,可以解决以往应急反应中存在的资料分散、资料更新慢、管理费用大以及大量信息难以提取、查询和使用等问题。GIS与震后应急反应的结合可以大大提高应急反应的速度和准确性。  相似文献   
979.
To clarify the possible influence of Microcystis blooms on the exchange of phosphorus (P) between sediment and lake water, an enclosure experiment was conducted in the hypereutrophic subtropical Lake Donghu during July-September 2000. Eight enclosures were used: six received sediment while two were sediment-free. In mid-August, Microcystis blooms developed in all the enclosures. There was a persistent coincidence between the occurrence of Microcystis blooms and the increase of both total P (TP) and soluble reactive P (SRP) concentrations in the water of the enclosures with sediments. In sediment-free enclosures, TP and SRP concentrations remained rather stable throughout the experiment, in spite of the appearance of Microcystis blooms. The results indicate that Microcystis blooms induced massive release of P from the sediment, perhaps mediated by high pH caused by intense algal photosynthesis, and/or depressed concentrations of nitrate nitrogen (NO3-N).  相似文献   
980.
本文对第四纪红壤及其发育的土壤中的6种必需阴离子态养分含量及其在土壤剖面中的分布进行了系统的讨论.结果表明,第四纪红壤中的各种必需阴离子态养分含量与土壤耕作熟化措施有关.荒地的NO、Cl-、H2BO较高,而开垦为旱地后,它们的含量下降;H2PO在土壤经过耕作熟化后有所提高;MoO的含量则基本保持不变;与其它阴离子显著不同的是.经耕作熟化后,土壤有效性SO含量急剧增加,不同的阴离子态养分在土壤剖面中的分布特点不同.  相似文献   
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