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61.
污泥好氧消化的研究现状及发展趋势   总被引:1,自引:0,他引:1  
污泥好氧消化是一种有效实用的污泥稳定技术 ,适用于处理量较小 (≤ 2 0 0 0 0m3 /d)的污水处理厂。在分析中 ,对污泥好氧消化的 3种工艺 (CAD、A/AD、ATAD)的工艺原理、影响参数及研究现状进行了详细的介绍 ,并在对国内外文献进行总结的基础上 ,分析了污泥好氧消化的研究方向与发展趋势  相似文献   
62.
The content of carbon (C), nitrogen(N), fossil carotenoids (TC) and chlorophyllderivatives (CD) in the sediments of five Estonianlakes was analysed. Historical records of man-inducedchanges on catchments were used for the interpretationof the obtained data. On the basis of the C/N ratiosit was estimated that the planktonic matter formed ca.25% (C/N ratio 24) to 90% (C/N ratio 8) of theorganic pool matter of lake sediments. In eutrophicLake Ruusmäe the fraction of the phytoplanktonproduced in lakes was highest, amounting toapproximately 80–95% of the deposited organic matter.Remarkable C/N changes were noted in the sedimentsfrom lakes Matsimäe and Viitna, where the contentof planktonic matter has increased during lastdecades, reflecting an increase in recreationalactivity around these lakes. The variations in pigmentconcentrations in the sediments of lakes Matsimäeand Ruusmäe could be explained by changes in theland-use that have altered the intensity of primaryproduction and conditions of TC and CD degradationbefore the final burial.  相似文献   
63.
介质阻挡放电降解流动态二甲基二硫废气   总被引:1,自引:0,他引:1  
采用介质阻挡放电等离子体技术(Dielectric Barrier Discharge,DBD)处理常压下流动态气体中的有机硫恶臭气体二甲基二硫(Dimethyl Disulfide,DMDS).研究了不同停留时间、进气浓度及外施电压条件下DMDS的转化,推导了DBD处理DMDS的动力学模型,并根据傅立叶红外(FT-IR)产物分析探讨了反应机理.研究结果表明,DMDS降解产物主要为CO2、SO2和H2O.在停留时间0.067 s、外施电压7500 V、进气量8.4m3·h-1的条件下,进气浓度为80 mg·m-3 DMDS的降解率达到64.3%,体积降解比量为2.26×10-2L·s-1·W-1,绝对处理量达到430 mg·h-1.  相似文献   
64.
Sustainable development, a concept which has been built with the sustainability of economic progression as a main thrust, has been a widely preferred model to traditional developmental models. However, the real meaning of what sustainable development is and should include has been an object of debate. On the one hand, differing from traditional economic developmental models, economic progress does not necessitate the practice of ‘sustainable development'. On the other hand, current levels of science and technology are still unable to solve several problems that arise with economic development. Sustainable development has transferred the responsibility of environmental destruction to that of developing countries. Lastly, instead of utilizing the best technology and leadership into formulating excellent environmental-protection policies, it is more important to create widespread awareness to the public on the need to protect the environment and thereby engage their participation in decision-making to actually realize what is truly ‘sustainable development'.  相似文献   
65.
洱海东区湖滨带现状及生态修复   总被引:2,自引:2,他引:2  
洱海是云贵湖区的一个重要淡水湖泊.近年来由于人类活动干扰的加强,造成洱海水质恶化、水生生态环境受到破坏,尤其是作为湖泊保护屏障的湖滨带,其生态结构破坏严重、生态功能退化,急需进行生态修复.针对洱海湖滨带的现状和主要环境问题进行了较为详细的分析,探讨了洱海湖滨带生态修复的设计分区、工艺流程和设计内容,提出了洱海东区湖滨带生态修复方案.  相似文献   
66.
高温厌氧消化处理城市有机垃圾的正交试验研究   总被引:7,自引:0,他引:7  
针对城市垃圾高温厌氧消化处理中反应复杂、影响因素多的特点,采用正交试验,利用自行设计的厌氧发酵罐,以产气量为观察值,分析含固率(TS)、消化温度和碳氮比(C/N比)对厌氧消化过程的影响,并分析比较了高产气区与低产气区的挥发性脂肪酸(VFA)以及比产气速率的变化情况.在相同条件下,高温可以提高系统的最大比产气速率,并且还可以有效抑制VFA的积累,提高总产气量.结果表明,温度对厌氧消化过程影响最大,TS次之,C/N比影响最小.  相似文献   
67.
Destruction of 4-phenolsulfonic acid (4-PSA) in water was carried out using anodic contact glow discharge electrolysis. Accompanying the decay of 4-PSA, the amount of total organic carbon (TOC) in water correspondingly decreased, while the sulfonate group of 4- PSA was released as sulfate ion. Oxalate and formate were obtained as minor by-products. Additionally, phenol, 1,4-hydroquinone, hydroxyquinol and 1,4-benzoquinone were detected as primary intermediates in the initial stages of decomposition of 4-PSA. A reaction pathway involving successive attacks of hydroxyl and hydrogen radicals was assumed on the basis of the observed products and kinetics. It was revealed that the decay of both 4-PSA and TOC obeyed a first-order rate law. The effects of different Fe ions and initial concentrations of 4-PSA on the degradation rate were investigated. It was found that the presence of Fe ions could increase the degradation rate of 4-PSA, while initial concentrations lower than 80 mmol/L had no significant effect on kinetic behaviour. The disappearance rate of 4-PSA was significantly affected by pH.  相似文献   
68.
目前,地震预报远未成熟而达到实用化阶段.造成人员生命和财产严重损失的是建筑设施等的倒塌和破坏.为了最大限度地减轻灾害,最佳选择是要提高建筑物的抗震性.这里介绍目前得到迅速发展并在世界各地重要建筑上得到广泛应用而具有防震减灾实效的抗震技术--建筑隔震技术.  相似文献   
69.
中国矿区土地退化因素调查:概念、类型与方法   总被引:7,自引:0,他引:7  
矿区是受人类活动高强度干扰和加速侵蚀的区域,其生态破坏与环境污染导致严重的土地退化,造成土壤质量下降、生物多样性丧失,给我国矿山环境管理与恢复治理带来新的问题与挑战,亟待辨识与查明导致矿区土地退化的主要驱动因素.笔者通过综合分析土地退化概念、类型和成因,进一步界定了矿区范围,阐明了矿区土地退化的内涵,分析了导致矿区土地退化的生态破坏、环境污染与自然侵蚀等驱动因素的研究进展.基于此,将矿区土地退化划分为生态破坏导致的土地退化、环境污染导致的土地退化和自然侵蚀导致的土地退化3大类型,提出了一套矿区土地退化因素调查的指标体系与方法建议.  相似文献   
70.
当建筑物出现重大问题或险情时,由构件裂缝的外观和成因对钢筋混凝土结构进行分析和应急评定,可快速、简便地发现事故原因和危险程度,从而为处理工程事故提供定性依据。  相似文献   
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