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381.
PHB监测A2/O工艺除磷及负荷率耦合关系的研究   总被引:1,自引:0,他引:1  
高尚  戴兴春  陈曦  高岩  朱勇  黄燕  黄民生  王国华 《环境科学》2008,29(11):3093-3097
以上海市白龙港城市污水厂初沉池污水为进水,培养驯化污泥并构建A2/O试验系统,监测PHB消耗、生成的动态变化,并分析其与除磷和BOD5负荷率的耦合关系.结果显示,曝气池中PHB的消耗与除磷呈现良好的正相关关系(p<0.05),平均消耗约140 mg左右的PHB可去除1 mg P;厌氧池中PHB的生成与释磷存在着极显著的正相关关系(p<0.01),平均释放1.17 mg的磷可生成约100 mg的PHB;厌氧池中PHB的含量与系统F/M的正相关性显著(p<0.05),负荷为0.176 g/(g·d)较负荷0.413 g/(g·d)下PHB的生成量平均减少约4 mg/g(以MLSS计);PHB的合成与厌氧池中BOD5的去除量的相关性较差(p>0.05),但与温度呈极为显著的正相关关系(p<0.01),温度的升高有助于微生物合成PHB,最高温度(33.2℃)比最低温度(17.1℃)活性污泥中PHB含量约增加5 mg/g(以MLSS计),占总量的20%左右.  相似文献   
382.
光助Fenton氧化法降解水中的活性艳蓝KN-R   总被引:2,自引:2,他引:0  
采用光助Fenton氧化法降解水中的活性艳蓝KN-R染料.实验结果表明,在溶液pH为3,Fe2+、过氧化氢、草酸质量浓度分别为5,75,2 mg/L,反应时间为60 min时,色度、COD和TOC的去除率分别达到99%,80%和51%以上.水中阴离子对降解反应有阻碍或抑制作用,阴离子对COD去除率的影响从大到小为:NO-3>Cl->HCO-3>BrO-3>HPO2-4:对TOC去除率的影响从大到小为:NO-3>HPO2-4>Cl->Hco-3>BrO-3.  相似文献   
383.
归纳总结安徽省自 1976年唐山大地震至 1998年 2 0余年弱震、少震的时期里地震谣传发生、发展的特征和紧急平息地震谣传的经验 ,结合实际提出了对地震谣传的长期预防对策。  相似文献   
384.
Xie L  Shang C 《Chemosphere》2007,66(9):1652-1659
Bromate reduction by Fe(0) was investigated under various conditions in batch tests. The bromate was primarily reduced to bromide ions with possible adsorption onto iron. Bromate reduction by Fe(0) can be described by pseudo-first-order kinetics. The differences in surface areas, numbers of reactive sites, impurities, pretreatment methods and numbers of repeated uses of iron affected the rates of bromate reduction through reducing or accumulating a passive oxide film on the iron surface. The reduction of bromate was significantly affected by only the dissolved oxygen content at supersaturated concentrations or by decreasing the pH from 6 to 5. Increasing the temperature increased the bromate reduction rate, which followed the Arrhenius relationship with activation energy of 52.6 kJmol(-1) and the reduction rate increased with increased mixing rates. These observations indicate that bromate reduction by iron is a surface-mediated process and diffusion to the surface is essential. Under the test conditions, modest inhibitory effects on bromate reduction by Fe(0) from nitrite, chlorate and bicarbonate were observed and the inhibitory effect from phosphate was relatively larger. Enhanced reactivity of Fe(0) to bromate was observed in the presence of nitrate or sulfate. These findings suggest that bromate reduction by Fe(0) can be an effective method for bromate control.  相似文献   
385.
Environmental and Ecological Statistics - Functional data analysis tools, such as function-on-function regression models, have received considerable attention in various scientific fields because...  相似文献   
386.
Identification of representative sampling sites is a critical issue in establishing an effective water quality monitoring program. This is especially important at the urban-agriculture interface where water quality conditions can change rapidly over short distances. The objective of this research was to optimize the spatial allocation of discrete monitoring sites for synoptic water quality monitoring through analysis of continuous longitudinal monitoring data collected by attaching a water quality sonde and GPS to a boat. Sampling was conducted six times from March to October 2009 along a 6.5 km segment of the Wen-Rui Tang River in eastern China that represented an urban-agricultural interface. When travelling at a velocity of ~2.4 km h(-1), this resulted in water quality measurements at ~20 m interval. Ammonia nitrogen (NH(4)(+)-N), electrical conductivity (EC), dissolved oxygen (DO), and turbidity data were collected and analyzed using Cluster Analysis (CA) to identify optimal locations for establishment of long-term monitoring sites. The analysis identified two distinct water quality segments for NH(4)(+)-N and EC and three distinct segments for DO and turbidity. According to our research results, the current fixed-location sampling sites should be adjusted to more effectively capture the distinct differences in the spatial distribution of water quality conditions. In addition, this methodology identified river reaches that require more comprehensive study of the factors leading to the changes in water quality within the identified river segment. The study demonstrates that continuous longitudinal monitoring can be a highly effective method for optimizing monitoring site locations for water quality studies.  相似文献   
387.
宋玉梅  王畅  刘爽  潘佳钏  郭鹏然 《环境科学》2019,40(8):3489-3500
饮用水源水体中残留微量多环芳烃(PAHs)对人体健康存在危害.以广州饮用水水源地为研究对象,采集广州部分水厂水源水体及底泥样品,考察了样品中16种PAHs含量及分布,采用美国环保署(USEPA)的RAGS风险评估模型,对水体中PAHs人体健康风险进行了评估.结果表明,广州饮用水水源地水体中PAHs的质量浓度未超过相应的水质标准限值,水体悬浮颗粒物和底泥中ΣPAHs含量处于低至中等水平.水源地水体PAHs暴露的单项非致癌风险指数和总非致癌风险指数均小于1,非致癌风险可以忽略.水源地水体PAHs单项致癌风险和总致癌风险在5. 53×10~(-7)~5. 34×10~(-6),可能存在致癌风险但低于最大可接受风险水平.水源地PAHs为混合型污染源输入,包括石油泄漏、石油燃烧和木材、煤以及生物质的不完全燃烧.水体中PAHs与底泥中PAHs含量密切相关,PAHs在两相间的分布存在平衡分配.  相似文献   
388.
We investigated the effect of calcium ion on the adsorption of humic acid (HA) (as a target pollutant) by powered activated carbon. The HA adsorption isotherms at different pH and kinetics of two different solutions including HA alone and HA doped Ca2+, were performed. It was showed that the adsorption capacity of powdered activated carbon (PAC) for HA was markedly enhanced when Ca2+ was doped into HA. Also, HA and Ca2+ taken as nitrate were tested on the uptake of each other respectively and it was showed that the adsorbed amounts of both of them were significantly promoted when HA and calcium co-existed. Furthermore, the adsorbed amount of HA slightly decreased with the increasing of Ca2+ concentration, whereas the amount of calcium increased with the increasing of HA concentration, but all above the amounts without addition. Finally, the change of pH before and after adsorption process is studied. In the two different solutions including HA alone and HA doped Ca2+, pH had a small rise, but the extent of pH of later solution was bigger.  相似文献   
389.
战略环境评价研究与实践进展   总被引:17,自引:0,他引:17  
回顾了战略环境评价的起源,发展历程,尤其是90年代以来的实践与研究成果;分析了当前研究趋势并提出了今后我国战略环境评价工作的重点,包括加强研究,建立保证体系和进行试点等。  相似文献   
390.
以2012年南四湖水质监测数据为依据,采用修正的卡森指数法(TSIM)对南四湖水质进行评价。结果表明,修正卡森指数的评价结果为TSIM=56.04,南四湖已达到富营养化的标准。根据评价结果,从工业废水、生活污水排放、底质、农业生产、渔业养殖的影响方面分析了水体富营养化的原因,从减少外源污染物、应用生物措施和发展健康水产养殖模式三个方面提出了南四湖水体富营养化的防治对策。  相似文献   
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