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991.
Xiyu?Zhao Yang?Yang Yanhong?Li Xun?Cui Yunhuai?ZhangEmail author Peng?XiaoEmail author 《Journal of Materials Science》2016,51(8):3724-3734
The design and fabrication of sustainable and efficient electrocatalyst for water splitting are crucial for rechargeable metal-air batteries and regenerative fuel cells. In this report, a highly stable and active NiCo-selenide electrocatalyst was successfully prepared by a facile two-step solvothermal approach. In 0.1 M KOH alkaline electrolyte solution, the novel NiCo-selenide electrocatalyst afforded the current density of 10 mA cm?2 at a lower overpotential of 393 mV, a smaller Tafel slope of ~89 mV dec?1 and better stability, compared with NiCo-based oxide and sulfide. 相似文献
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A method for measuring the multi-wavelength emissivity of a steel surface is proposed, and an applicable experimental apparatus is designed. Multi-wavelength radiant energy emitted from a sample was measured using a fiber-optic spectrometer and its temperature measured using a NiCrSi/NiSiMg thermocouple. Utilizing the unique vacuum control and background noise-shielding systems, we investigated the multi-wavelength emissivity of GCr15 steel at three different degrees of surface oxidation at temperatures ranging from 1000 \(^{\circ }\)C to \(1100\,^{\circ }\)C. The experimental results show that the multi-wavelength (0.7 \(\upmu \)m–0.9 \(\upmu \)m) emissivity increased substantially, from 0.409–0.565 to 0.609–0.702, once the steel was oxidized. In addition, the emissivity increased slightly with increasing temperature, but the trends for emissivity and wavelength were similar. To measure the surface temperature of casting billets based on multi-wavelength thermometry, the functional relationships between emissivity and wavelength at different extents of oxidation were determined. Temperature measurements based on our technique were compared with those from common colorimetric thermometry. Our approach reduced the temperature fluctuation from \(\pm 23\,^{\circ }\)C to \(\pm 3.5\,^{\circ }\)C, indicating that a reliable measurement of the multi-wavelength emissivity of GCr15 steel is obtained using this experimental apparatus. 相似文献
994.
Formal Specification and Quantitative Analysis of a Constellation of Navigation Satellites 下载免费PDF全文
Zhaoguang Peng Yu Lu Alice Miller Tingdi Zhao Chris Johnson 《Quality and Reliability Engineering International》2016,32(2):345-361
Navigation satellites are a core component of navigation satellite‐based systems such as Global Positioning System, Global Navigation Satellite System and Galileo, which provide location and timing information for a variety of uses. Such satellites are designed for operating on orbit to perform tasks and have lifetimes of 10 years or more. Reliability, availability and maintainability analysis of systems has been indispensable in the design phase of satellites in order to achieve minimum failures or to increase mean time between failures and thus to plan maintenance strategies, optimise reliability and maximise availability. In this paper, we present formal models of both a single satellite and a navigation satellite constellation and logical specification of their reliability, availability and maintainability properties, respectively. The probabilistic model checker PRISM has been used to perform automated analysis of these quantitative properties. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
995.
Angular Dependence of Exchange Bias and Magnetization Reversal Controlled by Electric‐Field‐Induced Competing Anisotropies 下载免费PDF全文
996.
Enhancing Interfacial Bonding between Anisotropically Oriented Grains Using a Glue‐Nanofiller for Advanced Li‐Ion Battery Cathode 下载免费PDF全文
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High‐Performance Polymer Tandem Solar Cells Employing a New n‐Type Conjugated Polymer as an Interconnecting Layer 下载免费PDF全文
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