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101.
P.M De CamposA.V Benedetti L.A De FariaV Cardoso J.F.C Boodts 《Electrochimica acta》2002,47(8):1283-1295
Electrodes of RhxTi(1−x)Oy nominal composition were prepared by thermal decomposition of the chloride or nitrate precursor salts dissolved in strongly acidic medium and applied by brush to both sides of a Ti° support. A systematic study of the influence of calcination temperature and time as well as oxygen flux was conducted. The coatings were characterised by SEM, EDAX, XRD, open circuit potential measurements and cyclic voltammetry (CV). Visible-ultraviolet spectrophotometry was employed to identify the chemical form of the precursor in solution while thermogravimetric analysis (TGA) was used to assess the decomposition temperature ranges. Optimisation of the coating preparation parameters showed coatings obtained from [Rh(H2O)6](NO3)3 precursor dissolved in HNO3 1:2 (v/v) and fired at 430 °C for 2 h in a 5 l min−1 oxygen stream-furnished stable electrodes having the highest electrochemically active surface area. 相似文献
102.
The equilibrium reaction 3'(Fe, Co)O'( ss ) +1/2O2 ( g ) ⇄ (Fe, Co)3 O4 ( ss ) was studied in the temperature range 970 to 1370 K for seven different total compositions of molar ratios 0.5 < Fe/(Fe + Co) ≤ 1.0. The equilibrium pressures of oxygen were determined by using galvanic cells incorporating calcia stabilized zirconia as solid electrolyte and the Fe/Co ratios in the solid-solution phases by wavelength dispersive spectrometry microprobe analyses. The activities of 'FeO' in the cobaltowüstite phase were then derived from the experimental results obtained. 相似文献
103.
The activation of propane using zeolite H-Y and Ga3+ exchanged zeolite Y indicates that in the presence of Ga3+ the mechanism of propane activation is changed from a cracking pathway to a dehydrogenation pathway. The presence of both Ga3+ and H+ are required to achieve this effect. 相似文献
104.
105.
添加尖晶石对氧化锌压敏电阻性能的影响 总被引:1,自引:0,他引:1
通过添加尖晶石(Zn7Sb2O(12))改性研制出电位梯度为100V/mm左右,压敏电压在82~150V,通流容量可达1600A/cm2,漏电流<2μA系列压敏电阻器,从而满足了国内电话交换机行业对82V、100V、120V、150V压敏电阻器的电性能要求。从工艺的角度解释了尖晶石对氧化锌瓷晶粒的作用原理,并分析了尖晶石的微观结构及粒度对瓷片电性能的影响。 相似文献
106.
The iron rhenate was compounded by chemical method, which may be generated during wear process of Fe-Re alloys at elevated
temperature. The friction coefficient of iron rhenate has been determined by a pin-on-disc device. The results show that iron
rhenate plays role of lubricating at RT-600 °C. The lubricating behavior is related to the matching pairs. The hardness of
the materials of matching pairs, compatibility of iron rhenate with materials of matching pairs and surface roughness of disc
affect the lubricating behavior of iron rhenate mostly. The principle of matching pairs is proposed.
Project supported by the National Natural Science Foundation of China
Synopsis of the first author Xiong Dangsheng. associated professor, born in 1960. Current research fields include high-temperature self-lubricating alloys
and tribological properties of material. 相似文献
107.
阐述了5052合金铸轧坯料生产时冷隔缺陷产生的机理,结合超型FATA—HUNTERΦ1003×1850mm机多年的生产实践经验,提出了消除铸轧冷隔缺陷的措施。 相似文献
108.
109.
In the present study WO3 thin films were deposited by sputtering onto ITO glass, W/ITO and Si substrates by using the glancing angle deposition (GLAD) technique, with the objective of applying these materials in electrochemical intercalation devices. The thin films microstructure and electrochemical behavior were determined through scanning electron microscopy (SEM) and cycling at constant current with potential limitation. By mainly adjusting the substrate holder speed rotation, pillar-type and helical-type structures were obtained under high and low speed rotation levels, respectively. The electrochemical results showed that the best charge capacity performance was obtained for the WO3/W/ITO films with pillar-type structures, which are more porous. 相似文献
110.
Shiqiang Hui Justin RollerSing Yick Xinge ZhangCyrille Decès-Petit Yongsong XieRadenka Maric Dave Ghosh 《Journal of power sources》2007
The advantages of lowering the operation temperature of SOFCs have attracted great interest worldwide. One of the major barriers to decreasing the operation temperature is the ohmic loss of the electrolyte. Maximizing the electrolyte ionic conductivity is of significant importance, especially in the absence of new electrolyte materials. The ionic conductivity of electrolytes can be influenced by many parameters. There has been an enormous effort in the literature for the improvement of the electrolyte ionic conductivity. From a practical point of view, this paper reviews various approaches to enhancing the ionic conductivity of polycrystalline zirconia- and ceria-based oxide electrolytes in the light of composition, microstructure, and processing. Suggestions are given for future work. 相似文献