δ15N在污水生物脱氮机理研究中的应用     

刘贤荣  闫秀懿  张永祥 《吉林地质》2003,22(1):54-57,82

近年来,硝酸盐氮的污染愈来愈严重.无论是地表水还是地下水都受到不同程度的氮污染.控制氮污染及处理氮污染问题已经提到我国水污染控制的议事日程.本文探索微生物处理含氮污水的过程中反硝化作用的脱氮机理,使用δ15N标识技术研究水体中三氮运移转化过程中的质量不守恒,证明δ15N标识技术研究确定不同形态氮的数量各系是可行的.研究水体中三氮质量不守恒现象,将解决含氮污水生物净化中污泥上浮问题、氮污染含水层生物修复中气阻问题.  相似文献   

城市缓流水体污染成因分析及维护对策   总被引：17，自引：0，他引：17       下载免费PDF全文

朱亮  蔡金榜  陈艳 《水科学进展》2002,13(3):383-388

在讨论城市缓流水体的运移特征、水化学过程及污染源的基础上,提出了建立科学的城市水务管理体制,城市水利工程与生态工程建设相结合,充分发挥水系工程在城市水体环境保护中的作用,以及完善暴雨污水综合治理方法等保护城市缓流水体的对策.  相似文献   

The implementation of fog water collection systems in South Africa     

J. Olivier  C. J. de Rautenbach   《Atmospheric Research》2002,64(1-4)

Two fog water collection systems (FWCS) have been implemented in South Africa. Both are located in areas where communities experience acute water shortages but which are prone to frequent fog episodes. The first was located at a high elevation site at the Tshanowa Junior Primary (JP) School in the Soutpansberg located in the Northern Province and the other near a small rural community at Lepelfontein along the West Coast. The former represents a mountainous site, while the latter is located on a low level coastal plain. The principal aim of the projects was to implement operational FWCSs to supply the communities with water. During the period 1999 to 2001 the total recorded cloud water yields at the Tshanowa JP School and Lepelfontein water collection sites were in the region of 72 422 and 148 691 l, respectively. This is equivalent to just over 2 l m⁻² day⁻¹ at the Tshanowa JP School and 4.6 l m⁻² day⁻¹ at the Lepelfontein site. Despite the relatively low average daily yields recorded, the total water volume collected on a particular day may be considerable. In fact, at both sites the maximum daily yield exceeded 3800 l. Fog deposition accounted for around 25% and 88% of the total water yield measured at the Tshanowa JP School and Lepelfontein sites, respectively. Both experiments indicated that fog water collection holds considerable potential as an alternative water source in the mountainous regions and along the West Coast of South Africa.  相似文献   

Contesting Domestic Ideals: queering the Australian home     

Andrew Gorman-Murray 《The Australian geographer》2007,38(2):195-213

The Australian home is a crucial site for both normalising and contesting acceptable modes of sexual identity, desire and behaviour. Social norms and government policies have imbricated the detached suburban dwelling with the heterosexual nuclear family form, consequently heterosexualising the ideal Australian home. But this discourse is simultaneously challenged by the domestic practices of gay men and lesbians, who use their homes to consolidate gay/lesbian identities, relationships and communities. As such, they unsettle the normative heterosexuality underpinning dominant, ideal conceptions of home. In this paper I present four vignettes which illustrate how some gay men and lesbians queer the ideal Australian home, generating domestic spaces which affirm sexual difference. In doing so, I highlight two key ways in which this process of ‘queering home’ works. First, through certain uses of home—activities taking place within domestic space. Second, through changes to the materiality of domestic space itself wrought by some homemaking practices, effectively embedding gay/lesbian identities and relationships within the physical environment of the home.  相似文献   

通辽地区污灌区土壤中重金属迁移规律   总被引：1，自引：0，他引：1  

孙立波  张兰英  张玉玲  王显胜 《世界地质》2007,26(1):71-74

通辽地区污灌区土壤土层剖面不同深度重金属铬、铜、镉、铅元素测试和分析结果表明，重金属在垂直方向上的浓度随着土层加深，含量减少，土壤对重金属具有吸附和过滤作用，污灌区地下水目前没有受到污染。  相似文献   

20世纪90年代中期以来国内外城市旅游研究比较   总被引：1，自引：0，他引：1  

朱梅  汪德根 《地理与地理信息科学》2007,23(4):70-75

对国内外13种期刊近十多年来发表的有关城市旅游的论文进行分析,比较国内外城市旅游研究历程、研究方法和研究领域的差异,发现国内在不少研究领域和研究方法上比国外起步晚,但经过近十多年的发展,研究领域有了新的突破,研究方法趋向多样化,且更加注重定量研究方法;提出国内城市旅游研究的未来发展方向。  相似文献   

Geotechnical properties of municipal sewage sludge   总被引：3，自引：0，他引：3  

Brendan C. O’Kelly 《Geotechnical and Geological Engineering》2006,24(4):833-850

The geotechnical properties of municipal sewage sludge, in particular those pertinent to the handling and landfilling of the material, are presented. Index, drying, compaction, shear strength and consolidation tests were conducted on the material at different states of biodegradation. The organic content and specific gravity of solids were found to be inversely related, with typical organic contents of 50–70% and specific gravity of solids values of 1.55–1.80. The density of the compacted material was low in comparison with mineral soils. Standard Proctor compaction yielded a maximum dry density of 0.56 tonne/m³ at 85% water content. Laboratory vane-shear and triaxial compression tests indicated that, below about 180% water content, the shear strength of the sludge material increased exponentially with reducing water content. Consolidated-undrained triaxial compression tests on the pasteurised sludge material indicated an effective angle of shearing resistance of 32° for the moderately degraded material and 37° for the strongly degraded material. Biogas was produced at rates of up to 0.33 L/day/kg slurry due to ongoing biodegradation and the resulting pore pressure response must be taken into account in any stress analysis. Consolidation tests using the hydraulic consolidation cell, oedometer and triaxial apparatus indicated that the sludge material was highly compressible although practically impermeable, for example the coefficient of permeability for the moderately degraded slurry was of the order of 10⁻⁹m/s. However, creep deformation was significant with typical coefficient of secondary compression values of 0.02–0.08 for the compacted material. A more free-draining material was produced at higher states of biodegradation.  相似文献   

排污活动对长江口滨岸潮滩营养元素N累积运移的影响及作用机制   总被引：5，自引：4，他引：1  

付金沐  刘敏  侯立军  欧冬妮  刘巧梅 《地理科学》2007,27(5):695-700

选择长江口滨岸潮滩作为典型研究区,研究了排污活动对潮滩营养盐N环境地球化学过程的影响。结果发现排污口滨岸潮滩上覆水、表层沉积物孔隙水和表层沉积物中的NH₄⁺-N、TIN等都有显著累积效应,而NO_x^--N在长江口滨岸潮滩上覆水、表层沉积物孔隙水和表层沉积物中并未出现累积高峰值,表明外源输入不是潮滩环境中NO_x^--N主要来源。分析结果还显示,排污口潮滩沉积物-水界面间N分子扩散通量明显大于非排污口,表明排污活动加剧了潮滩沉积物-水界面间营养盐N的扩散过程。  相似文献   

油层回注含聚合物污水的适应性     

殷茵  刘大锰  黄金凤  王金站 《现代地质》2006,20(4):641-646

通过分析油田聚合物驱产出水处理后聚合物的分子特性以及各组分变化,认为含聚合物污水对油层的主要影响因素是污水中聚合物的含量。由岩心驱替实验结果证明,聚合物浓度不同的污水对具不同渗透率油层的适应性是不同的。建议对不同类型油层的注入水选择适合的聚合物浓度。这一研究成果对聚合物驱后的污水利用以及研究注入油层的水质标准具有可参考的意义。  相似文献   

矿井水污染的地表水灌溉入渗过程中的水岩作用   总被引：8，自引：1，他引：7  

吴耀国  沈照理  钟佐燊  李广贺 《煤田地质与勘探》2004,32(3):38-40

分析了污水灌溉对地下水化学环境影响的研究现状, 以淄博煤矿区矿井水污染的孝妇河水进行灌溉的区域为例, 利用土柱实验研究煤矿矿井水污染的地表水灌溉入渗过程中的水岩作用。结果表明, 灌溉水入渗过程中发生可溶盐的溶解及离子交换等水岩作用, 而且在灌溉的初期主要表现为溶解作用, 而后以离子交换作用为主。溶解作用的速率, 在污水入渗初期大, 而后逐渐减小, 直至趋于零。   相似文献