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1.
有色冶金中的离子交换膜电解技术 总被引:1,自引:0,他引:1
谭翎燕 《有色金属(冶炼部分)》2002,(4):16-20
离子膜电解技术在有色冶金工业中有重要的应用价值 ,膜的选择透过性和不同的电极过程相结合可完成各种冶金过程。综述了离子交换膜电解技术在高纯金属的制备、无机物的电化合成、多价离子氧化状态的控制及金属离子的分离等冶金领域的研究现状 ,分析了该技术的特点 ,并指出了该技术要实现工业化必须解决的主要问题 相似文献
2.
Surface hardening of Ti-6Al-4V alloy was achieved by carburization in a molten salt bath containing BaCO3 as the carbon-yielding agent with electrolysis within the temperature range 790–930°C. The hardness of the total carburizing layer (TCD) is influenced by the bath temperature, the applied current density and the carburizing period. The major hardening effect is considered to be the formation of a solid solution of carbon in -Ti. The oxide film wrapping at the outermost surface of cathodically charged specimens, identified to be mainly BaTiO3, was formed irrespective of the bath temperature during the quenching process and has no effect on the surface hardening. The optimal carburizing parameters obtained in this study for surface hardening are carburizing at 930±10°C (bath temperature) and 0.3 A/Cm2 (applied current density) for 90 min (carburizing period), while those for tribological properties improvement are carburizing at 860±5°C and 0.3 A/Cm2 for 90 min. 相似文献
3.
工件在电镀前抛光是一道费工费时的工序,我们利用电解、液体磨料冲刷复合抛光工艺,可及时去除电解过程中在工作表面产生的钝化膜,提高电解抛光质量和速度,降低劳动强度,此工艺特别适用于批量较大、表面形状较复杂的零件的抛光。 相似文献
4.
5.
张韵雅 《有色金属材料与工程》1989,(5)
改造双氧水电解生产法的目的是降低电耗。试验证明最有效的方法是改变阳极结构。作者采用钽银复合铂金电极,使电解槽体积及阴阳极极距缩小、槽电压降低、电流浓度提高、槽液流速加快、冷却方式改善,从而使电压下降18.1%,直流电单耗下降22.8%,达到国内最先进的水平,综合经济效益达133.6万元。 相似文献
6.
电解法制取金属铬粉工艺研究 总被引:3,自引:0,他引:3
范家友 《昆明冶金高等专科学校学报》2001,17(4):27-30
文章分析了电解法制取金属铬的工艺,对其中除铁、冷冻、电解三个工序进行了重点研究,得出了完善工艺流程的办法。 相似文献
7.
A two-cell planar stack in the Jülich F-design with solid oxide cells has been built and the reversible operation between fuel cell and electrolysis modes has been demonstrated. The cells were anode supported cells (ASC) with yttria-stabilized zirconia (YSZ) electrolytes, Ni/YSZ hydrogen electrodes and perovskite oxygen electrodes with lanthanum strontium cobalt ferrite (LSCF). This paper summarizes and discusses the preliminary experimental results on the long-term aging tests of the reversible solid oxide planar short stack for fuel cell operation (4000 h) at a current density of 0.5 A cm−2 which shows a degradation of 0.6% per 1000 h and for steam electrolysis operation (3450 h) and co-electrolysis operation of CO2 and H2O (640 h) under different current densities from −0.3 to −0.875 A cm−2 which show different degradation rates depending on current density and on steam or co-electrolysis. 相似文献
8.
9.
The electrochemical oxidation of hydroquinone and substituted hydroquinones has been studied over graphite and platinum electrodes in different alcohol media. The results have shown that good yields of the corresponding alkoxy-substituted phenols can be obtained with high selectivities towards the hydroquinone monoalkyl ether. A mechanism is put forward to explain the formation of the alkoxyphenol through the creation of a quinhydrone complex, formed between the hydroquinone and benzoquinone, which is then attacked by the alcohol acting as a nucleophile.In this study, the effect of sulfuric acid as supporting electrolyte and acid catalyst was compared with that of methanesulfonic acid. It was found that sulfuric acid gave the best yield for different alkoxyphenols. The alcohols under investigation were C1-C8, and it was found that the longer the chain length of the alcohol, the slower the tendency to produce alkoxyphenols. Branched alcohols such as secondary and tertiary alcohols showed no reactivity towards the quinhydrone complex. Some of the yields obtained are as follows: 4-methoxyphenol (97%), 4-ethoxyphenol (71.4%) and 4-propoxyphenol (81.1%). 相似文献
10.
T. P. Aleksandrova A. A. Vais A. I. Masliy V. A. Burmistrov A. A. Gusev S. K. Bagavieva 《Materials and Manufacturing Processes》2015,30(6):798-803
Chemical and electrochemical methods to deposit nanolayers of metallic silver and its low-solubility compounds on polymer fiber surfaces are presented. The morphology and phase composition of the coatings were studied and their antimicrobial activity compared. We find that the antimicrobial activity of the coatings increases substantially with increasing solubility. Their high surface area and high porosity make synthetic fibers with these coatings promising for application as antimicrobial filters in air purification and water treatment systems. 相似文献