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1.
Steel production is an energy- and water-intensive process: large quantities of water are used for cooling, process and environmental-technical
applications. In the mid-1990s, Arcelor Gent, a large integrated carbon steel producing company in Flanders (Belgium), started
a number of water-related projects: the existing water infrastructure was adapted: the water from the coke plant was biologically
treated; canal water was demineralised using reverse osmosis; waste water from the blast furnaces was neutralised with alkaline
water from the steel plant. As a result of these projects, the quantity of discharged waste water was reduced by a factor
of 2 (water recycling doubled from a factor of 10 to a factor of 20), and the discharge of pollutants decreased. Also resource
consumption decreased: lime used in the steel plant, could be recovered to precipitate Zn in the waste water of the blast
furnaces.
Arcelor Gent obtained for these projects several Environmental Awards. 相似文献
2.
比较曝气头曝气以及膜曝气两种曝气方式支持的菌藻共生系统在不同的运行条件下对污染物的去除效能,探讨去除机理。结果表明,以膜曝气为基础的MABAR对氨氮、总氮、磷、化学需氧量(COD)的去除负荷相对于以曝气头曝气为基础的HABAR,最高分别提升1.44、21.22、3.08、52.09 kg/m2/m3。藻类积累方面,MABAR在5个阶段的积累量都高于HABAR,最高提升15.17 mg/cm2。这不但归因于膜曝气良好的无吹脱和高效的碳化能力为自养藻类提供了充足的无机碳,而且膜曝气为一些十分有利于藻类生长的细菌,例如Acidovorax、Rhodobacter和Acinetobacter,提供了良好的生存环境。MABAR不但能够提升去除效能,还能够促使光生物膜反应器抵抗冲击,维持稳定,这对未来光生物反应器的实际应用提供了一种新的运行方式。 相似文献
3.
4.
Carbon dioxide has been previously identified as a critical volatile factor that stimulates hyphal growth ofGigaspora margarita, a vesiculararbuscular mycorrhizal fungus, and we determined the optimal concentration at 2.0%. The beneficial effect of CO2 on fungal development is also visible in the presence of stimulatory (quercetin, myricetin) or inhibitory (naringenin) flavonoids. Sterile root exudates from carrot seedlings stimulate the hyphal development ofG. margarita in the presence of optimal CO2 enrichment. Three flavonols (quercetin, kaempferol, rutin or quercetin 3-rutinoside) and two flavones (apigenin, luteolin) were identified in carrot root exudates by means of HPLC retention time. Flavonols like quercetin and kaempferol are known to have stimulatory effects on hyphal growth ofG. margarita. 相似文献
5.
基于以往学者对企业社会责任的研究,结合共生理论,提出城市企业社会责任理念,通过分析城市企业社会责任治理主体之间的关系,探索建立城市企业社会责任共生系统,并在此基础上构建城市企业社会责任评价框架体系,最后提出城市企业社会责任治理建议,推进城市企业社会责任生态系统的多方共同治理。 相似文献
6.
毛峰 《数码设计:surface》2010,(6):71-73
传统设计元素与现代设计手法如何消除对峙,促进相互融合,一直是艺术设计界值得研究的问题。两者虽在表现形式上存在着一些差异,但它们的审美目的和创造性价值所传达出来的艺术信息是具有共性的,文章将传统图形中共生现象定为研究对象,探究其成因、特点、继承及影响,这将对于如何进一步尊重传统、发掘传统;如何继续深层次研究促使中国传统图形的在当代视觉传达中的应用,起到抛砖引玉的作用。 相似文献
7.
Engineer Bainomugisha Jorge Vallejos Elisa Gonzalez Boix Pascal Costanza Theo D'Hondt Wolfgang De Meuter 《Software》2012,42(3):331-356
The iPhone SDK provides a powerful platform for the development of applications that make use of iPhone capabilities, such as sensors, GPS, Wi‐Fi, or Bluetooth connectivity. We observe that so far the development of iPhone applications has mostly been restricted to using Objective‐C. However, developing applications in plain Objective‐C on the iPhone OS suffers from limitations, such as the need for explicit memory management and lack of syntactic extension mechanism. Moreover, when developing distributed applications in Objective‐C, programmers have to manually deal with distribution concerns, such as service discovery, remote communication, and failure handling. In this paper, we discuss our experience in porting the Scheme programming language to the iPhone OS and how it can be used together with Objective‐C to develop iPhone applications. To support the interaction between Scheme programs and the underlying iPhone APIs, we have implemented a language symbiosis layer that enables programmers to access the iPhone SDK libraries from Scheme. In addition, we have designed high‐level distribution constructs to ease the development of distributed iPhone applications in an event‐driven style. We validate and discuss these constructs with a series of examples, including an iPod controller, a maps application, and a distributed multiplayer Scrabble‐like game. We discuss the lessons learned from this experience for other programming language ports to mobile platforms. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
8.
9.
This study was carried out to investigate the ability of an artificial microalgal–bacterial consortium to remediate an oilfield wastewater using laboratory-scale fluidized bed reactors (FBRs) under lighting. The consortium consists of an oil-degrading bacterial community and a microalgae, Scenedesmus obliquus GH2. The microbes were immobilized onto Ca-alginate beads and filled to the FBRs. The influence of hydraulic retention time (HRT) on the removal of chemical oxygen demand (COD), total nitrogen, NH3-N and oil concentration was investigated over 40 operational days. The synergistic relationship in the algal–bacterial microcosm was clearly demonstrated, since for the four parameters tested, the highest removal was recorded in the system inoculated with both algae and bacteria. In the algal–bacterial FBR, at 16 h HRT, the average effluent concentrations of COD, NH3-N and oil were 92, 24 and 4.8 mg/L, respectively, corresponding to removal efficiencies of 70.8%, 61.2% and 84.2%, respectively. The effluent could meet the grade 2 as required by the national discharge standard of China. However, the effluent quality of the bacterial- or algal-only case could not satisfy the grade 3 discharge standard at 16 h HRT. The algal–bacterial biomass exhibits lowest effluent microtoxicity and highest dehydrogenase activity in comparison with bacterial-only and algal-only cases. This study reveals that the consortium containing dual microbial species has potential for microbial remediation of oilfield wastewater. 相似文献
10.
吴丽萍 《延边大学学报(自然科学版)》2022,(1):30-36
研究一类具有反馈控制变量和出生率具有密度制约的偏利共生模型的平衡点稳定性.首先通过分析系统的平衡点,得到系统正平衡点和边界平衡点存在的条件;其次通过构造适当的Lyapunov函数,得到在一定条件下系统的正平衡点和边界平衡点是全局稳定的;最后利用数值模拟验证了所得结果的正确性. 相似文献