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41.
从硬度、耐磨性、摩擦及耐蚀性等几个方面研究了镀层的性能。同时研究了镀层成份及镀液中稳定剂对镀层耐蚀性的影响,交通过电化学手段和X-光电子能谱XPS地镀层进行了研究。 相似文献
42.
Xueqin Song Shiru Le Xiaodong Zhu Long Qin Yan Luo Yanwei Li Kening Sun Ying Chen 《International Journal of Hydrogen Energy》2017,42(24):15808-15817
Bi2O3 doped BaFeO3?δ on the B-site as a cobalt free perovskite cathode for intermediate temperature solid oxide fuel cells is evaluated. The BaFe1?xBixO3?δ (BFBx) powders are synthesized by solid state reaction. It is found that Bi2O3 doping stabilizes the BaFeO3 cubic phase. The new cathode is compatible with Gd0.1Ce0.9O1.95 even calcined at 1000 °C for 10 h. The electronic conductivity shows a transformation from semiconductor to metal conductor, and achieves its maximum value of 28.1 S cm?1 for BFB10 at 800 °C. The δ is as high as 0.408 for BFB10 determined by iodometric titration. This leads to the free volume in crystal lattice of BFB10 21.60% higher than that of BaNb0.05Fe0.95O3?δ. The area specific resistance is only 0.133 Ω cm2 for BFB10 at 750 °C and the average TEC is 26.697 × 10?6 K?1 measured from room temperature to 800 °C. The peak power density of Ni-YSZ|YSZ|GDC|BFB10 cell is 646.28 mW cm?2 at 750 °C, higher than that of single cell using LSCF as cathode. These show that BFBx perovskite oxides with cubic phase are promising cathodes for intermediate temperature solid oxide fuel cells. 相似文献
43.
Jia Xu Xiaoliang Zhou Xiaolong Dong Lu Pan Kening Sun 《International Journal of Hydrogen Energy》2017,42(23):15632-15640
Finding cost-effective and efficient anode materials for solid oxide fuel cells (SOFCs) is of prime importance to develop renewable energy technologies. In this paper, La and Fe co-doped SrTiO3 perovskite oxide, La0.3Sr0.7Ti0.3Fe0.7O3?δ (LSTF0.7) composited with CeO2 is prepared as a composite anode by solution infiltration method. The H2 and CO oxidation behavior and the electrochemical performance (electrochemical impedance spectra, I–V and I–P curves) of the scandia-stabilized zirconia (ScSZ) electrolyte supported cells fabricated by tape casting with the LSTF0.7–CeO2 composite anode are subsequently measured at various temperatures (700–850 °C). Electrochemical impedance spectra (EIS) of the prepared cells with the LSTF0.7–CeO2|ScSZ|La0.8Sr0.2MnO3 (LSM)–ScSZ configuration illustrate that the anode polarization resistance distinguished from the whole cell is 0.072 Ω cm2 in H2, whereas 0.151 Ω cm2 in CO at 850 °C. The maximal power densities (MPDs) of the cell at 700, 750, 800 and 850 °C are 217, 462, 612, 815 mW cm?2 in H2 and 145, 349, 508, 721 mW cm?2 in CO, respectively. Moreover, a significant decrease of anode activation energy towards H2 oxidation is clearly demonstrated, indicating a better electrochemical performance in H2 than in CO. These results demonstrate an alternative composite anode with high electrocatalytic activity for SOFC practical applications. 相似文献
44.
针对复杂大型装备的单件生产模式产品规格繁多、结构复杂且个性化强、工艺变更频繁且难以标准化、工艺编制难度大、加工周期长、对资源能力依赖严重等特点,以及制造服务提供企业在订单阶段难以对客户需求与当前制造能力的匹配度进行正确、快速预判等问题,提出了基于零件特征的单件生产制造需求和制造资源能力模型。引入基于层次分析法与直觉模糊集的特征工序矩阵与设备资源能力矩阵匹配算法,计算零件需求和资源的匹配度,实现订单阶段的用户需求和制造资源的快速匹配,最后通过企业实例验证了该方法的有效性。研究结果有助于提高单件制造企业的订单评估质量,降低接单风险,增强企业的竞争力。 相似文献
45.
天然食品防腐剂——乳链菌肽(Nisin) 总被引:6,自引:2,他引:6
乳链菌肽是某些乳酸链球菌产生的一种天然食品防腐剂,它强烈抑制许多引起食品腐败的革兰氏阳性菌的生长,繁殖,并对人体安全无毒。已被广泛应用于热加工食品,尤其是罐头食品,奶制品,高蛋白食品和乙醇饲料的防腐保鲜。此外,加入乳链菌肽还可降低食品加工过程中的能源消耗,改进食品的营养价值,外观,风味和质地,延长货架寿命。对乳链菌肽的应用和开发将具有重大的经济效益和社会效益。 相似文献
46.
高频脉冲电沉积镍钻合金镀层的硬度研究 总被引:1,自引:0,他引:1
在硫酸盐电解液中,采用脉冲电源电沉积了镍钻合金.研究了电解液中COS04的浓度及脉冲参数对镀层中Co含量和镀层显微硬度的影响.采用SEM和XRD研究了镀层的表面形貌和微观结构.结果表明,镀层中的Co含量对镀层硬度有显著影响,当CO含量小于55 mass%时,镀层的硬度随着Co含量的增加递增.Co含量较低时,合金由面心立方结构(fcc)的固溶体组成. 相似文献
47.
48.
基于马尔柯夫链,讨论了遗传算法的渐进收敛性,给出了群体状态转换矩阵,证明了群体从任一初始状态出发,最终将收敛于吸收状态,为遗传算法的应用奠定了理论基础. 相似文献
49.
Yufei Zhao Yuxia Zhang Zhiyu Yang Yiming Yan Kening Sun 《Science and Technology of Advanced Materials》2013,14(4)
AbstractScientists increasingly witness the applications of MoS2 and MoO2 in the field of energy conversion and energy storage. On the one hand, MoS2 and MoO2 have been widely utilized as promising catalysts for electrocatalytic or photocatalytic hydrogen evolution in aqueous solution. On the other hand, MoS2 and MoO2 have also been verified as efficient electrode material for lithium ion batteries. In this review, the synthesis, structure and properties of MoS2 and MoO2 are briefly summarized according to their applications for H2 generation and lithium ion batteries. Firstly, we overview the recent advancements in the morphology control of MoS2 and MoO2 and their applications as electrocatalysts for hydrogen evolution reactions. Secondly, we focus on the photo-induced water splitting for H2 generation, in which MoS2 acts as an important co-catalyst when combined with other semiconductor catalysts. The newly reported research results of the significant functions of MoS2 nanocomposites in photo-induced water splitting are presented. Thirdly, we introduce the advantages of MoS2 and MoO2 for their enhanced cyclic performance and high capacity as electrode materials of lithium ion batteries. Recent key achievements in MoS2- and MoO2-based lithium ion batteries are highlighted. Finally, we discuss the future scope and the important challenges emerging from these fascinating materials. 相似文献