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1.
2.
Properties and Performance of Cation-Doped Ceria Electrolyte Materials in Solid Oxide Fuel Cell Applications 总被引:1,自引:0,他引:1
Christopher Milliken Sivaraman Guruswamy Ashok Khandkar 《Journal of the American Ceramic Society》2002,85(10):2479-2486
Cation-doped CeO2 electrolyte has been evaluated in single-cell and short-stack tests in solid oxide fuel cell environments and applications. These results, along with conductivity measurements, indicate that an ionic transference number of ∼0.75 can be expected at 800°C. Single cells have shown a power density >350 mW/cm2 . Multicell stacks have demonstrated a peak performance of >100 mW/cm2 at 700°C using metallic separators. 相似文献
3.
Studies were made on the thermally stimulated discharge currents (TSDCs) in pure (undoped) and Fe-doped polystyrene films as a function of polarizing field, polarizing temperature and dopant concentration. While undoped films exhibited a single peak, doped films showed two peaks one at low temperatures and another at high temperatures. The low temperature peak, which exhibits a shift towards lower temperatures with increasing dopant concentration, is attributed to the relaxation of the main chain, while the high temperature peak, which shows a tendency to shift towards higher temperatures with dopant concentration, is due to space charge polarization. The TSDCs were higher for low dopant concentrations than their undoped counterparts, while for high concentrations of the dopant, the TSDCs decreased. Formation of charge transfer complexes at low dopant concentrations and molecular aggregates at higher dopant concentrations are suggested as the possible reasons for this behaviour. 相似文献
4.
针对目前对高度表进行原位检测的需求,设计了一种新的高度模拟方法;该方法的实现以ARM为核心,通过高度模拟电路产生各种需要的高度电压信号,从而达到高度模拟的目的,并且无需对机载高度表进行拆装,操作简单、快捷、可靠性较高;实验结果表明,这种方法的高度模拟精度较高,具有一定的实用价值和经济效益. 相似文献
5.
The catalytic activities of WCI6Ph4Sn, MoCl5Ph4Sn and tetrabenzyltitanium were examined in the polymerization of acetylene. The structure, morphology and electrical conductivity of the doped and non doped polyacetylene were also studied. 相似文献
6.
The PbO2 and F−-doped PbO2 (F-PbO2) film electrodes have been prepared by an electrodeposition process onto platinum substrate. The changes of their electrochemical activity for oxygen evolution (OE) reaction with accelerated electrolysis time have been studied. The results show that the activity of the electrodes decreases with increasing electrolysis time. This can be attributed to the conductivity variations, which are caused by the decrease of the oxygen vacancy concentration in PbO2 films during OE. The mechanism of the decrease of the oxygen vacancies has been investigated. For F-PbO2 film electrodes, though its electrochemical activity is somewhat lower than that of undoped one, its activity stability is much higher in comparison with that of PbO2. The influence of F− doping on the activity of PbO2 film electrodes has been also discussed. 相似文献
7.
原位聚合制备尼龙6/纳米SiO2复合材料研究 总被引:10,自引:0,他引:10
对原位聚合制备尼龙6/纳米SiO2进行研究。结果表明,无论是否对纳米SiO2复合材料进行偶联化处理,其表面均将在原位聚合过程中与尼龙6产生接枝;SiO2表面接枝物的生成,可在某种程度上造成体系结晶程度的降低,但复合体系的力学性能主要由SiO2粒子的分散程度、粒子和其体之间的相界面性质等因素决定;采用经偶联剂处理并具有较小粒径和较大比表面积的SiO2对尼龙6进行复合,可使复合体系的力学性能指标达到较高的水平,且硅烷偶联剂的最佳用是为SiO2的3%左右。 相似文献
8.
Oxidation of trans-polyacetylene lowers the activation energy for conduction from 16 kcal mol?1 to 11 kcal mol?1 for oxidation levels of (C2H2On)x, n = 0.144, 0.207 and 0.550. Maximum conductivity levels for 0 < x < 0.144 doped with I2 were almost identical. At long I2 doping times all samples exhibited some loss of conductivity. E.s.r. experiments indicate that: (1) linewidth is directly proportional to oxygen content, and (2) iodine doping is not diffusion controlled. All data are consistent with a molecular picture of PAC consisting of highly reactive localized spin states that are selectively oxidized, and less reactive delocalized states that affect conductivity more strongly via doping. 相似文献
9.
采用原位聚合方法制备了定向碳纳米管/聚甲基丙烯酸甲酯复合材料,并且研究了该复合物的耐磨损性.对定向碳纳米管及其复合物进行了傅立叶红外吸收光谱分析、扫描电镜及光学显微镜观察.采用砝码质量法评价了复合物的耐磨损性.分析结果表明,混酸处理后定向碳纳米管附带了-OH、-COOH基等极性基团.混酸处理后定向碳纳米管束状结构被破坏,定向碳纳米管可以单管形态分散于基体中,碳纳米管表面包覆着PMMA.砝码质量法耐磨损性测试结果表明,定向碳纳米管的加入可提高PMMA复合物的耐磨损性和耐划痕性,当定向碳纳米管用量为0.7%时,复合物的耐磨损性能提升了54%. 相似文献
10.
C. R . Kao 《金属学报(英文版)》1995,(Z1)
REACTIVEDIFFUSIONBETWEENSiANDNbCAT1300℃C.R.Kao(DepartmentofChemicalEngineeringNationalCentralUniversityChungLi,Taiwan)J.Woodf... 相似文献