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Mohammad A. Alim 《Journal of the American Ceramic Society》1989,72(1):28-32
The lumped parameter/complex plane analysis technique revealed several contributions to the terminal admittance of the ZnO—Bi2 O3 based varistor grain-boundary ac response. The terminal capacitance has been elucidated via the multiple trapping phenomena, a barrier layer polarization, and a resonance effect in the frequency range 10−2 ≤ f ≤ 109 Hz. The characterization of the trapping relaxation behavior near ∼ 105 Hz (∼ 10−6 s) provided a better understanding of a previously reported loss-peak. The possible nonuniformity in this trapping activity associated with its conductance term observed via the depression angle of a semicircular relaxation in the complex capacitance ( C *) plane has been postulated. 相似文献
64.
总结了弱酸性链盐镀锌和碱性锌酸盐镀锌的优缺点,并综合两者的优点,提出了一种弱酸性铵盐与碱性锌酸盐双缸套镀锌工艺。钝化膜的性能得到了改善。 相似文献
65.
介绍了锌精矿制酸系统采用三级旋风除尘器替代电除尘器的设计及运行情况。为了提高旋风除尘器的除尘效率,硫酸系统各工序作了适当调整。运行实践表明,三级旋风除尘器除尘效果良好,硫酸系统能长期稳定运行。 相似文献
66.
我国锌盐工业的现状与展望 总被引:2,自引:0,他引:2
阐述了我国锌盐工业的发展现状、存在的问题和面临的机遇与挑战,提出了发展锌盐工业的建议。 相似文献
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The electrowinning of zinc from zinc chloride with a molten chloride electrolyte was investigated. The electrolysis of zinc chloride shows ohmic limitations. The energy consumption is to a large extent determined by the anodic reaction, the evolution of chlorine. The chlorine gas plume was visualised in a see-through furnace and images were analysed to determine the plume angle. This parameter serves as an input parameter for a model to determine the ohmic contributions of the electrolyte, the plume and a layer of chlorine bubbles sticking to the anode, as well as the plume velocity. The results indicate that the major contribution (60%) to the ohmic drop is due to a stagnant layer of bubbles growing and sticking to the anode, thereby decreasing the effective anode area by coverage. The plume velocity influences coverage characteristics to some extent, which influences the ohmic drop. 相似文献
69.
Model compound studies were carried out to elucidate the reaction mechanisms taking place during the liquefaction of coal with the hydrogen produced from the reaction of zinc and water. In compounds of the type Ph-(CH2)n-Ph the splitting of the aliphatic bridge was easier with higher n values. Ether type compounds such as diphenylether were unreactive although the C-O bond in dibenzylether was easily cleaved. Condensed ring aromatic compounds gave low conversion with hydrogenation being facilitated by an increase in ring number. Phenolic compounds such as phenol did not react well, but the reactivity increased with increase in aromatic ring size. The cleavage of the aliphatic bridge was accelerated by the OH group, for example, in the case of 4-hydroxydiphenylmethane bond scission was about 15 times higher than that of diphenylmethane. Heterocyclic compounds were unreactive. 相似文献
70.
We review our X-ray absorption spectroscopy studies of adsorbate geometries on the O-terminated (000
) and Zn-terminated (0001) basel faces, as well as the non-polar (10
0) prism face of ZnO. Studies employing near-edge X-ray absorption fine-structure (NEXAFS) and surface X-ray absorption fine-structure (SEXAFS) are included. 相似文献