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741.
以实际全比例非循环管道中试平台中水泥砂浆内衬球墨铸铁管为研究对象,通过分析生物膜的理化指标及微生物的群落结构来研究环氧树脂封面层对管道生物膜的影响.研究发现,相比于普通水泥砂浆内衬的球墨铸铁管,增加环氧树脂封面层后的管道不易吸附、沉积各种物质,对生物膜细菌丰度及群落结构均有影响,其管壁生物膜细菌总数为4.01×104copies/cm2,可培养菌数量为1.40×10CFU/cm2,另外其物种丰度较高而多样性较低.因此增加环氧树脂封面层的水泥内衬球墨铸铁管是一种更为优良的管材. 相似文献
742.
为研究河口陆基养殖塘底泥中铁的迁移和转化机制,本文测定了福建省3个河口养虾塘养殖期表层和亚表层底泥沉积物中活性铁含量及间隙水的常见组分.结果表明,不同站点间晶质Fe(III)、非硫Fe(II)、有机铁、铁硫化物含量存在显著差异.间隙水SO42-和Cl-可能是影响不同站点间Fe的形态和分布存在异质性的主要环境影响因子之一.盐度较高的养虾塘,铁的硫化物含量较高,有机铁和晶质Fe(III)含量较少.陆基养虾塘底泥沉积物中活性铁含量按固相Fe(III) > 铁硫化物 > 非硫Fe(II) > 有机铁的顺序排列.养虾塘亚表层沉积物铁硫化物(FeS和FeS2)含量高于表层沉积物,而表层沉积物有机铁含量与间隙水SO42-和NH4+浓度高于亚表层沉积物.铁硫化物的生成一定程度上降低河口陆基养虾塘沉积物营养盐污染的潜在风险. 相似文献
743.
利用污泥基生物炭(SDBC)固定铁物质制备了一种污泥基非均相催化剂(Fe-SDBC),用于活化过硫酸盐(PS)以降解酸性橙G(OG).Fe-SDBC/PS体系显示出对OG优异的降解性能.评价了影响降解的因素(Fe-SDBC金属负载量、Fe-SDBC投加量、初始pH值和PS浓度).并通过X射线荧光光谱仪(XRF)、傅立叶变换红外分析仪(FT-IR)和拉曼光谱仪(Raman)对Fe-SDBC进行了表征.自由基清除剂实验表明,SO4·-和OH·自由基均在降解过程中生成,且活化PS历程主要发生在非均质催化剂表面.分析Fe-SDBC活化PS的潜在机理,表明不同形式的铁物质是PS分解的主要贡献者,Fe2+/Fe3+的转化循环提高了Fe-SDBC持久活化PS的效果.Fe-SDBC循环实验表明其对活化PS具有较好的可重用性,连续3次24h降解高浓度污染物仍能发挥作用.综上所述,Fe-SDBC作为一种污泥基非均相催化剂可以持久活化PS,从而实现OG的降解. 相似文献
744.
745.
Many developed countries are using a challenging Zero Waste concept to change current waste management practices to more sustainable methods of managing waste, including household waste. The concept includes waste prevention; high levels of recycling and recovery of all resources from waste; and behavioural change. This research provides a case study on the development of a Zero Waste Strategy (ZWS) for Charnwood Borough Council (CBC), an English Local Authority (LA), which has an established household waste management system.This paper describes the steps taken by the authors, together with CBC to devise and implement a ZWS. A series of focus groups were held involving elected members of the LA and members of the community. The aim was to identify the core aspects of environmental, operational and social demands in order to prioritise actions to be included in a draft ZWS. The draft underwent wider public consultation, which highlighted areas for revision, and following revision has been adopted by the LA. The ZWS takes into account local issues, local policies, alongside national strategies and legislation.Many of the options identified during this research complement each other and if used in combination may see large steps taken towards Zero Waste. This is difficult to achieve without a holistic approach to waste generation, collection, treatment and disposal. Key findings from this research are to switch the focus from recycling to reuse and waste prevention, alongside increasing education and behaviour change programmes for householders. Additionally, the potential value of separately collecting food waste, with a recognised high potential yield, must be explored to ensure meeting targets set in the ZWS and the requirements of the Landfill Directive. 相似文献
746.
Lapland is one of the most attractive nature-tourism areas in Europe, and tourism is vital for local economy. However, recreational tourist activities such as skiing, hiking and horse riding deteriorate the unique and vulnerable nature of Northern Finland. Erosion and wearing of tourist areas negatively affects biodiversity and ecosystem services and reduce the attractiveness of the region. Tourism is also the source of other environmental disturbances such as wastes. Currently, in Lapland, the prevalent waste treatment method is disposal, and wastes are transported over long distances due to lack of recipient facilities for waste management. The suggestion for sustainable waste management Scenario presented in this paper is to find a synergistic solution to both of these problems, by local treatment of bio-waste in an anaerobic digestor and utilization of digestate to revegetate eroded land. It is proposed that bio-waste is co-digested with sewage sludge and offal from slaughterhouses in Ylläs in the municipality of Kolari. An estimated 500–1000 t of digestate could be produced and used in tourist areas annually. Experiences from existing seasonal bio-waste collection schemes and interviews of local tourist enterprises and tourists indicate that there is willingness to extend the source separation of wastes. Assessment of the digestion Scenario suggests that economic costs of investment could be offset by avoided costs and by additional environmental and social benefits. It is concluded that this zero waste approach could lead to an improved image of Lapland as a sustainable tourist destination. 相似文献
747.
双酚S(BPS)是一种新兴的内分泌干扰物,在环境中广泛存在,并对自然环境和人体健康有严重危害。制备了FeS-Fe0纳米复合材料作为催化剂,明确了FeS-Fe0纳米复合材料活化PS体系(FeS-Fe0/PS体系)的反应条件对去除BPS的影响,包括材料中FeS与Fe0摩尔比、材料投加量、PS浓度、溶液初始pH值等,并应用X射线衍射分析、X射线光电子能谱分析等技术表征该复合材料,通过反应体系对比实验、Fe离子溶出实验、PS的消耗实验、猝灭实验、电子顺磁共振波谱检测,探究了FeS-Fe0纳米复合材料的活化机理。实验结果表明:FeS-Fe0/PS体系降解BPS的最优条件为溶液初始pH=3、FeS与Fe0摩尔比1∶25、材料投加量0.10 g/L、PS浓度1.0 mM;FeS-Fe0/PS体系中产生的硫酸根自由基(SO4·-)和羟基自由基(HO·)可降解BPS,且HO·占主导作用;FeS-Fe0纳米复合材料表面的FeS促进了铁离子的溶出和循环,因此其活化能力优于纳米零价铁。 相似文献
748.
随着我国钢铁企业安全生产标准化的不断深入开展,钢铁企业安全生产状况趋于稳步好转。本文分析了钢铁企业安全生产的现状,并就近年来大中型钢铁企业安全生产事故情况进行了统计分析,对存在的问题进行了深入的探讨,提出了相应的改进对策与建议。 相似文献
749.
Salar Rezapour 《Chemistry and Ecology》2014,30(2):147-155
A factorial design with different levels of elemental S and cow manure was used to investigate the effects of S and manure on SO4-S, P and micronutrient availability in a calcareous saline–sodic soil. The results revealed that the recovery of SO4-S increased significantly (p≤0.05) in all treatments as elemental S increased, particularly when in combination with manure. The interactional effects of S° and manure application rates resulted in a decrease in soil pH of 0.1 to 0.9 units and increases in soil EC from 0.1 to 2.6 dS m?1 as result of an increase in the number of oxidisers and the oxidation rate of elemental S. Application of S° in combination with manure led to an increase in soil-available-P (0.6–40 mg kg?1), DTPA-Zn (0.2–3.9 mg kg?1) and DTPA-Fe (0.1–5.6 mg kg?1). 相似文献
750.
腐殖酸对As(V)在覆铁砂介质中吸附行为的影响 总被引:2,自引:0,他引:2
对腐殖酸(HA)进行了成分分析及红外表征,并从HA浓度、pH值、As(Ⅴ)初始浓度等方面,研究了HA对As(Ⅴ)在覆铁砂介质中吸附行为的影响.结果表明,随着HA浓度的升高,总砷去除率逐渐降低.当HA浓度增加到25mg.l-1时,与不存在HA条件下相比,总砷去除率降低了12%左右.溶液pH值影响As(Ⅴ)的去除,pH值从6升高到8时,总砷去除率从52.1%降到了39%.其中的作用机理主要是HA与As(Ⅴ)在覆铁砂表面形成竞争吸附,HA争夺了As(Ⅴ)的吸附点位.此外,HA与Fe(Ⅲ)的络合作用也是导致覆铁砂对砷的去除率降低的一个重要原因. 相似文献