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从土壤中分离、筛选得到一株稳定高效的微生物絮凝剂产生菌,命名为B—27。考察了碳源、氮源、pH、温度、培养时间等多种因素对絮凝剂(命名MBF—27)絮凝效果的影响。实验结果表明,当碳源为葡萄糖、氮源为酵母膏、pH为7.0、温度为35℃、培养时间为72h时,絮凝剂MBF—27对高岭土悬浊液的絮凝率可达93.8%。红外光谱扫描分析表明,该絮凝剂的主要成分为多糖类物质。同时,生物絮凝剂MBF—27对气田废水的COD和色度去除率分别达到60.77%和86.1%,优于传统的絮凝剂聚乙烯丙胺(PAM)和三氯化铁(FeCl3)。 相似文献
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絮凝剂的开发及其应用进展 总被引:2,自引:1,他引:2
文章对无机絮凝剂、有机高分子絮凝剂、微生物絮凝剂(MBF)和其他絮凝剂进行了介绍,综述了絮凝剂的研究现状,对以上几种絮凝剂在废水处理等领域中的应用情况进行了阐述。比较了几种絮凝剂的特点,并对絮凝剂的发展趋势进行分析和展望。 相似文献
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新型生物絮凝剂的研究 总被引:8,自引:0,他引:8
本文对近两年来新型生物絮凝剂的研究报道进行了综述。这些新型生物絮凝剂的研究领域包括复合型生物絮凝剂的研制,微生物絮凝剂与其它絮凝剂的复配,微生物絮凝剂的生物学研究,以及微生物絮凝剂培养条件的优化等。并对今后生物絮凝刺的研发方向进行了展望。 相似文献
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微生物絮凝剂的研究现状与发展趋势 总被引:5,自引:0,他引:5
相对于传统絮凝剂而言,微生物絮凝剂具有絮凝效果好、应用范围广、易生物降解、对环境安全、无二次污染的特点。文章综述了微生物絮凝剂的类型和特点,详细阐述了其絮凝机理,分析了影响微生物絮凝剂絮凝性能的因素以及微生物絮凝剂在水处理中的应用。指出了当前微生物絮凝剂研究存在的问题以及今后的发展趋势。 相似文献
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在水质评价中,表示某一流域水质情况的指标众多,而不同的指标间往往存在不同程度的相关性。其中有些相关性甚至非常显著,这使它们提供的信息有可能发生重叠。用主成分分析综合处理可以产生新的指标,而这些新的指标彼此互补相关又能综合反映水质的情况。本文通过应用主成分分析逐步降维综合处理的特性对辽河水质进行评价,对辽河四个断面的污染程度做了综合评价。然后再应用主成分分析法选取主要污染指标,结合迭代聚类模型对主成分分析得到的结果进行分类。 相似文献
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本文应用模糊数学方法对近年宜宾市城区大气环境质量进行综合评价,并与常用的其它几个模式进行可比分析,其更能描述大气污染程度的特点。因此,模糊综合评判法对大气环境质量评价是较为理想的一种评价方法,它具有较强的实用性。 相似文献
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Subhes C Bhattacharyya 《Natural resources forum》1995,19(2):135-142
The removal of energy subsidies is considered to be the first step towards a better environment. In order to pursue a policy for subsidy removal, one needs to know exactly the amount of subsidies accorded to different fuels. In this paper, the subsidies involved in the coal sector in India are estimated. Existing prices are reviewed, economic prices are estimated and the two are compared to arrive at appropriate subsidies or taxes. The subsidies are also distributed among different sectors and policy implications of subsidy removal are discussed. Finally, the need to have a larger data sample to study the coal industry is stressed, in order to better understand the cost structure . 相似文献
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The Army Corps of Engineers (ACE) is generally responsible for the implementation of federal Clean Water Act wetland regulations. It therefore plays an important role in the protection of wetlands within the United States. Unfortunately, past evaluators of ACEs implementation of these regulations found low rates of regulatory compliance. However, the fact that two states have taken responsibility for the implementation of these regulations within their boundaries provided the opportunity to assess whether one of these states might be doing a better job of enforcement. This paper reports on compliance with some of these regulations within one Michigan region. We evaluated permittee compliance with paperwork filing requirements related to wetland mitigation projects. Sixty-seven percent of county road commission permittees were out of compliance with at least one filing requirement. Forty percent of private and non-county government permittees were out of compliance. Our results therefore suggest that serious problems exist with Michigans implementation of wetland regulations. They do not suggest that compliance in this state is significantly better than in states under ACE administration. We believe that increased agency monitoring and enforcement would improve compliance. 相似文献
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S. Rocky. Durrans Sasa Tomic 《Journal of the American Water Resources Association》2001,37(5):1203-1214
ABSTRACT: In recent years, several approaches to hydrologic frequency analysis have been proposed that enable one to direct attention to that portion of an overall probability distribution that is of greatest interest. The majority of the studies have focused on the upper tail of a distribution for flood analyses, though the same ideas can be applied to low flows. This paper presents an evaluation of the performances of five different estimation methods that place an emphasis on fitting the lower tail of the lognormal distribution for estimation of the ten‐year low‐flow quantile. The methods compared include distributional truncation, MLE treatment of censored data, partial probability weighted moments, LL‐moments, and expected moments. It is concluded that while there are some differences among the alternative methods in terms of their biases and root mean square errors, no one method consistently performs better than the others, particularly with recognition that the underlying population distribution is unknown. Therefore, it seems perfectly legitimate to make a selection of a method on the basis other criteria, such as ease of use. It is also shown in this paper that the five alternative methods can perform about as well as, if not better than, an estimation strategy involving fitting the complete lognormal distribution using L‐moments. 相似文献
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This paper incorporates the results of a survey of recycling activity and attitudes in one UK community, the city of Norwich. The principal aims of the study were to identify the operation of the local market in secondary materials and to assess householder attitudes towards new recycling ventures and the use of recycled paper products. The main findings of the study indicate that a well established secondary paper and metals markets does exist in Norwich. Householder attitudes to recycled products seem, as far as paper is concerned, to depend upon the quality (texture and colour) of the products. As for the collection of secondary materials, better deployment of existing volunteer/charity based groups would appear to be a more ‘economic’ strategy than direct local authority involvement. 相似文献
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论述了用国产的低压离子色谱仪、电导检测器作为测定特高含硫油气田废水中F-、Cl-、Br-、SO离子的可行性,并讨论了分析条件、最低检出限、精密度、准确度以及干扰等,及对国家标样及实际样品进行了测定。结果表明该法简单、快速、灵敏、准确,是目前较为理想的测定特高含硫油气田废水中无机阴离子的方法。 相似文献
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Lawrence Nchekwube Nwankwo 《Local Environment》2006,11(1):95-108
Violent crime has plagued Nigerian society. It is in this context that some traders in the southeastern part of the country put together the Bakassi Boys—a security apparatus to parallel the Nigeria Police. The Bakassi attracted both praise and criticism. In this paper, I review the Bakassi phenomenon as a local initiative that tried to integrate elements of the traditional cosmology and ways of policing in response to the escalation of crime. The Bakassi being a child of crisis, there were flaws in their operation. By exploring the lessons that one can learn from the Bakassi experiment and outlining the challenges that it poses, one might hope to harness the lessons of a local initiative that failed in order to respond better to the socio-political issues that engineered its emergence. 相似文献