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排序方式: 共有1039条查询结果,搜索用时 31 毫秒
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概述了出口巴西大跨越输电导线用超高强度钢绞线的生产,通过生产工艺的控制、原材料的选用及设备的购置,所生产的产品完全满足工程技术条件要求。 相似文献
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《International Journal of Hydrogen Energy》2019,44(36):20345-20354
Using a citrate-nitrate process, BaCe0.9-xZrxY0.1O3-δ (x = 0, 0.5, 0.6, 0.7 and 0.8) nanopowders were synthesized, on the basis of which proton-conducting solid electrolytes (average size of coherent scattering region (CSR) - 15–53 nm) were obtained by spark plasma sintering (SPS) at a low temperature (900°С). The dependence of phase composition, microstructure and electrophysical properties of the obtained samples on ZrO2 content and consolidation conditions was established. It was found that the BaCe0.4Zr0,5Y0.1O3-δ solid solution had the highest electrical conductivity among zirconium-containing ceramic materials in the studied concentration range. It was shown that SPS is a promising method for obtaining solid electrolytes for proton-conducting solid oxide fuel cells (PCFC) at lower temperatures (by 400–500°С), compared to traditionally-used temperature conditions (1400–1800 °C). 相似文献
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《International Journal of Hydrogen Energy》2019,44(21):11020-11032
Eu doped La2NiO4 powders, with the general formula La2-xEuxNiO4+δ denoted as LENOx (for x = 0, 0.2, 0.4, 0.6 and 0.8), were synthesized via the mechanical milling reaction method. The Eu3+ doping content has a remarkable influence on structural and electrochemical properties. The phase identification and morphology were studied by X-ray diffraction (XRD), Raman spectroscopy, Infrared spectroscopy (IR), A laser size analyzer and scanning electron microscopy (SEM). Lattice parameters were calculated using the Rietveld method. It was observed that the lattice parameter values in LENOx systems varied with the amount of Eu3+. The latter was symmetrically deposited by spin coating on both surfaces of an Ce0.8Sm0.2O1.9 (SDC) electrolyte and studied using AC impedance spectroscopy. The electrochemical properties were studied using two-probe impedance spectroscopy and results showed that the ASR of LENOx was enhanced by the Eu3+ dopant content x. Results also showed that LNEO0.2 had the lowest Area specific resistance (ASR) at 700 °C and it was therefore concluded that doping with the appropriate amount of Eu3+ can further improve the properties of a nickelate cathode. 相似文献
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《低温学》2016
The data resulting from the thermal-hydraulic test of the ITER TF CICC are used to determine the flow partition and the overall effective heat transfer coefficient (hBC) between bundle and central channel in a direct way, i.e. by analysis of the heat transfer between both flow channels, based on the mass and energy balance equations and the readings of thermometers located inside the cable. In cases without a local heat source in the considered cable segment the obtained hBC values were consistent with those obtained in earlier studies by analysis of experimental data using indirect methods. It was also observed that the transverse heat transfer was strongly enhanced in a cable segment heated from outside. This phenomenon results from the mass transfer from the bundle region to the central channel. The experimental hBC data obtained for the case without a heat source in the considered segment were also compared with those calculated using various heat transfer correlations. 相似文献
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Semiconductor‐ionic materials could play an important role in advanced fuel‐to‐electricity conversion 下载免费PDF全文
Functional semiconductor‐ionic materials can be used to realize a single component or so‐called “three‐in‐one” fuel cell design. Such materials integrate the functionalities of fuel cell's anode, electrolyte, and cathode into one component. The underlying principle of a single‐component fuel cell design combines material band structures with ionic species/transport. The performance values of such devices could exceed that of traditional fuel cells. This could represent a major progress in fuel cell science and technology and lies grounds for a new direction of fuel cell R&D and commercialization. 相似文献
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本文介绍了高压变频器在寿光金太阳热电厂75t/h循环流化床锅炉的应用情况,应用实例表明,使用高压变频系统,改善了设备的运行工况,用户节能效果明显。 相似文献
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目的研究某地区长期运行的导线的表面状态、表面成分以及电晕特性,分析老化导线的表面特性变化规律。方法采用场发射扫描电子显微镜分析导线表面物质成分及分布状态,采用紫外成像仪对施加不同电压等级下电晕放电光子数进行计数,表征其放电的强弱程度。结果导线表面物质成分中非金属元素主要是氧、碳、硫、硅和少量的磷,金属元素主要是铁、铝、钙、钠、镁、钾,且表面状态与所处环境有关;长期运行导线表面在相同放电电压下放电光子数比新导线多。结论污秽颗粒、不规则的表面结构是长期运行的导线在正常运行电压下发生电晕放电的根源,导线表面的污秽成分与所处地区有关,导线表面凹凸不平会导致其起晕电压比新导线要小。导线的运行年限对表面状态和电晕放电特性有影响。 相似文献