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61.
Iron(III) oxide tablets were electrolytically reduced to iron in molten sodium hydroxide at 530 °C and recovered to produce
iron with 2 wt.% oxygen suitable for re-melting. The cell was operated at 1.7 V and an inert nickel anode was used. The thermodynamics
and mechanism of the process was also investigated. By controlling the activity of sodium oxide in the melt, the cell could
be operated below the decomposition voltage of the electrolyte with the net sequence of events being the ionization of oxygen,
its subsequent transport to the anode and discharge leaving behind iron at the cathode. A reduction time of 1 h was achieved
for a 1 g oxide tablet (close to the theoretical reduction time predicted by Faraday’s laws) at a current density of 520 mA cm−2 with iron phase yields of ∼90 wt.%. The energy consumption was 2.8 kWh kg−1. 相似文献
62.
64.
第九次节能工作会议后,冶金工业掀起了节能降耗的新高潮。各企业都从本单位 实际出发,狠抓节能降耗工作,节能增效成绩显著。大中型钢铁生产企业全年节能350万t标煤,超 出1997年初冶金工作会议确定的全行业节能300万t目标。创造效益28亿元。 相似文献
65.
In recent years, the concept of digital twin (DT) is attracting more and more attention from researchers and engineers. But there is still no consensus on what a right DT is. On one hand, some common models are renamed as DTs. On the other hand, some DTs extremely pursue ‘the same’ as physical objects, which bring unnecessary complexities to them. In this paper, we try to answer two questions from the point of view of model engineering: how to define a right digital twin, and how to build a right digital twin. The concept and related technologies of model engineering are introduced. Some basic principles and a set of metrics for a right DT are given. An evolutionary concurrent modeling method for DT (ECoM4DT) is proposed not only inheriting the theory from classic M&S methods but also highlighting the characteristics of DT compared with traditional models to systemically guide the DT modeling process. 相似文献
66.
运用复杂网络理论的基本原理和有关方法,对理工医文等学科、专业之间的合作规律和人员合作方式进行探讨,以某高校2005-2010年医工合作情况作为实例展开研究,采用5年的合作数据作了计算分析,研究了高校内部理工医文开展学科交叉工作的特点及其运行情况、医工交叉合作中存在问题,客观分析其原因,提出了解决的办法,为今后开展高校系统的理工医文交叉合作,建设电子化交叉平台. 相似文献
67.
云计算联盟的体系结构对云计算联盟的设计、实现和资源管理效率产生重要的影响。由于云计算联盟的构成和运行过程具有典型的复杂系统特性,基于涌现理论和复杂网络理论对云计算联盟的体系结构进行建模,提出了一种基于域和复杂网络理论的云计算联盟体系结构模型,并对该模型中资源的发布和发现机制进行了详细的研究。 相似文献
68.
Controlled experiments to study corrosion effects due to external varying fields in embedded pipelines 总被引:1,自引:0,他引:1
We present controlled laboratory tests carried out to study corrosion effects due to induction currents on pipes embedded in environments with electrical resistance lateral discontinuities. Sacrificial anodes were connected to underground pipes, and corrosion rates were estimated by measuring the mass loss in each anode. We considered 1 Hz and 50 Hz inducting fields, and the effects produced on the pipes were compared with cases without an external field. The results indicated an increase in the corrosion rate when the pipe was under the effect of induction currents, particularly where there was a change of electrical resistance in the soil. 相似文献
69.
Incorporating of hydrous ferric oxide(HFO) inside porous supports with large sizes has become an effective way to decontaminate the water from heavy metals. Ubiquitous anions like sulfate are usually present in high concentrations in water, and might greatly affect adsorption behavior of hybrid HFO. Here, a polymer-based HFO-CPS was fabricated by encapsulating nano-HFO inside a chloromethylated polystyrene polymer(CPS) and the reactivity of HFO-CPS with Cu(Ⅱ) was evaluated in the presence of sulfate ions.Surface complexation theory was firstly employed to describe the effect of sulfate on Cu(Ⅱ) adsorption edges of hybrid HFO-CPS, where constant capacitance model(CCM) was adopted. The available weak adsorption site Fe_((2))OH of hybrid HFO-CPS was found to decrease from 20% Fe to 5% Fe, which might be caused by the pore plugging effect after HFO encapsulation. With the assumption that a ternary complex was formed, the effect of sulfate on Cu(Ⅱ) adsorption by HFO-CPS were successfully described by CCM using the optimized Fe_((2))OH site under different sulfate concentrations(1 or 10 mmol·L~(-1)) and Cu/Fe ratios(0.0042 or 0.0252). It is confirmed that the formation of Fe OHCu SO_4 ternary surface complexes played an important role in enhancing Cu(Ⅱ) adsorption on HFO-CPS in the presence of sulfate. 相似文献
70.
总结了解放45年来上海钢铁工业所取得的成就,重点阐述了技术、工艺、装备方面的现状和不足以及发展目标,指出:只有实行改革开放,加快技术改造,才能提高上海钢铁工业的总体水平,提高经济效益,也才能使老企业焕发青春,步入现代化钢铁工业之林。 相似文献