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61.
62.
The electrochemical properties of an electrochemical double-layer capacitor electrode based on an ultra-long (500 μm), aligned, carbon nanotube array (ACNTA) in Et4NPF6/propylene carbonate electrolyte are examined. The specific capacitance of the ACNTA electrode in an organic electrolyte is 24.5 F g−1, which is larger than that obtained in an aqueous electrolyte. The results of ac impedance measurements show that the ACNTA electrode gives a high power density and an excellent rate capability in an organic electrolyte. It is shown that the ACNTA electrode has a lower equivalent series resistance and a better rate capability than activated carbon electrode. This is due to the fact that ACNTA possesses a larger pore size and a more a regular pore structure. Both these features are conformed by scanning electron microscopic and nitrogen gas adsorption studies. 相似文献
63.
StudyofBi_2O_3-basedRareEarthSolidElectrolyteUsedinFuelCell¥HeLanying;ChenGuangyu;LiuJiang;SuWenhui(DepartmentofPhysics,JilinU... 相似文献
64.
在钼丝炉内氩气保护下,利用固体电解质定氧探头测定了含镓1.87%~6.21%范围内Fe-Ga-O三元系平衡时的氧活度,通过处理得到镓在铁液中的标准溶解自由能等热力学参数与温度的关系。 相似文献
65.
A new discharge system for resistive self-heating has been constructed for the measurement of accurate thermophysical properties. A constant-current pulse is used to heat metals over a time interval of 50 to 100 s, reaching temperatures up to the boiling point. New techniques have been developed to obtain sound speeds in the pulse-heated sample, emissivities, and vapor pressure. A new pyrometer allows the extension of the measured temperature range down to the melting point of copper. 相似文献
66.
67.
X. Q. Ma H. Zhang J. Dai J. Roth R. Hui T. D. Xiao D. E. Reisner 《Journal of Thermal Spray Technology》2005,14(1):61-66
This work addresses the fabrication of membrane-type solid oxide fuel cells (SOFCs) operating at medium temperatures, where
all components are fabricated by plasma spray technology, and the evaluation of the performance of the SOFC single unit in
a temperature range of 500 to 800 °C. Single cells composed of LaSrMgO3 cathodes, LaSrGaMgO3 (LSGM) electrolytes, and Ni/yttria-stabilized zirconia anodes were fabricated in successive atmospheric plasma-spraying processes.
Plasma-spraying processes have been optimized and tailored to each layer to achieve highly porous cathode and anode layers
as well as high-density electrolyte layers. A major effort has been devoted to the production of the LSGM electrolyte that
has a high density and is free of cracks. Electrochemical impedance spectroscopy was used to investigate the conductivity
of the electrode layers, and particularly the resistance of the electrolyte layer. It revealed that the heat treatment had
a great influence on the specific conductivity of the sprayed electrolyte layers and that the specific conductivity of the
heat-treated layers was dramatically increased to the same magnitude as is typical for sintered LSGM pellets. The experimental
results have demonstrated that the plasma-spraying process has a great potential for the integrated fabrication of medium-temperature
SOFC units.
The original version of this article was published as part of the ASM Proceedings, Thermal Spray 2003: Advancing the Science and Applying the Technology, International Thermal Spray Conference (Orlando, FL), May 5–8, 2003, Basil R. Marple and Christian Moreau, Ed., ASM International,
2003. 相似文献
68.
The effects of SO2 and SO3 in the environment on the hot corrosion behavior of Ni in the temperature range 750–950°C has been studied. Below the melting point of Na2SO4 (884°C), rapid corrosion takes place by formation of a Na2SO4-NiSO4 melt, which can penetrate the porous oxide scale and give rise to sulfide information by coming in contact with the metal. The distribution of the sulfides depends on the SO2 level in the ambient gas. Continued corrosion occurs by a sulfidation-oxidation mechanism. At temperatures above the melting point of Na2SO4, accelerated degradation occurs via dissolution of the surface scale, followed by reprecipitation of the oxide in a nonprotective form.Deceased 相似文献
69.
Novel technology of purification of copper electrolyte 总被引:10,自引:1,他引:10
The effects of arsenic with different valence states on the purification of copper electrolyte were studied and a novel technology of purification of copper electrolyte by copper arsenite was proposed. The results show that the purification performance of As(Ⅲ) compounds is better than that of As(Ⅴ) compounds. The purification technology by copper arsenite has the advantages of simple operation, high purification performance and low cost in comparison with other technologies and its appropriate purification conditions are that copper arsenite concentration is 18 g/L, reaction temperature is 65 ℃ and reaction time is 8 h. The removal rates of Sb and Bi are 53.22% and 58.67% respectively under these conditions. The purification principle show that a kind of yellow precipitate mainly composed of arsenic, antimony ( Ⅴ ), bismuth and oxygen forms in electrolyte after copper arsenite is added, and consequently antimony and bismuth are removed from electrolyte. 相似文献
70.
REN Jianshi ZHAO Huilin ZHANG Gongshu Institute of Metal Research Academia Sinica.Shenyang China ZHANG Gongshu Senior Engineer Institute of Metal Research Academia Sinica Shenyang China 《金属学报(英文版)》1990,3(7):65-69
Glow discharge cathodic sputtering of alloys containing second phase precipitates or injectedoxide particles has been observed with energy dispersive X-ray spectrometer and scanningelectron microprobe.It was shown that the formation of cones during the sputtering in thesealloys is due to masking of the matrix by glow sputtering second phase precipitates or oxideparticles.At steady state,the density of cottes were found to be a function of the densities pre-cipitates or oxide particles in bulk alloy.In addition to the changes of local sputtering rate,theelectrostatic effect may play a role on the formation fo cones. 相似文献